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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a process for the desulfurization of a light boiling range fluid catalytic cracked naphtha. More particularly the present invention employs catalytic distillation steps which reduce sulfur to very low levels, makes more efficient use of hydrogen and causes less olefin hydrogenation for a full boiling range naphtha stream.
[0003] 2. Related Information
[0004] Petroleum distillate streams contain a variety of organic chemical components. Generally the streams are defined by their boiling ranges which determine the composition. The processing of the streams also affects the composition. For instance, products from either catalytic cracking or thermal cracking processes contain high concentrations of olefinic materials as well as saturated (alkanes) materials and polyunsaturated materials (diolefins). Additionally, these components may be any of the various isomers of the compounds.
[0005] The composition of untreated naphtha as it comes from the crude still, or straight run naphtha, is primarily influenced by the crude source. Naphthas from paraffinic crude sources have more saturated straight chain or cyclic compounds. As a general rule most of the “sweet” (low sulfur) crudes and naphthas are paraffinic. The naphthenic crudes contain more unsaturates and cyclic and polycylic compounds. The higher sulfur content crudes tend to be naphthenic. Treatment of the different straight run naphthas may be slightly different depending upon their composition due to crude source.
[0006] Reformed naphtha or reformate generally requires no further treatment except perhaps distillation or solvent extraction for valuable aromatic product removal. Reformed naphthas have essentially no sulfur contaminants due to the severity of their pretreatment for the process and the process itself.
[0007] Cracked naphtha as it comes from the catalytic cracker has a relatively high octane number as a result of the olefinic and aromatic compounds contained therein. In some cases this fraction may contribute as much as half of the gasoline in the refinery pool together with a significant portion of the octane.
[0008] Catalytically cracked naphtha gasoline boiling range material currently forms a significant part (˜⅓) of the gasoline product pool in the United States and it provides the largest portion of the sulfur. The sulfur impurities may require removal, usually by hydrotreating, in order to comply with product specifications or to ensure compliance with environmental regulations. Some users wish the sulfur of the final product to be below 50 wppm.
[0009] The most common method of removal of the sulfur compounds is by hydrodesulfurization (HDS) in which the petroleum distillate is passed over a solid particulate catalyst comprising a hydrogenation metal supported on an alumina base. Additionally copious quantities of hydrogen are included in the feed. The following equations illustrate the reactions in a typical HDS unit:
RSH+H 2 →RH+H 2 S (1)
RCl+H 2 →RH+HCl (2)
2RN+4H 2 →2RH+2NH 3 (3)
ROOH+2H 2 →RH+2H 2 O (4)
[0010] Typical operating conditions for the HDS reactions are:
Temperature, ° F. 600-780 Pressure, psig 600-3000 H 2 recycle rate, SCF/bbl 1500-3000 Fresh H 2 makeup, SCF/bbl 700-1000
[0011] After the hydrotreating is complete, the product may be fractionated or simply flashed to release the hydrogen sulfide and collect the now desulfurized naphtha. The loss of olefins by incidental hydrogenation is detrimental by the reduction of the octane rating of the naphtha and the reduction in the pool of olefins for other uses.
[0012] In addition to supplying high octane blending components the cracked naphthas are often used as sources of olefins in other processes such as etherifications. The conditions of hydrotreating of the naphtha fraction to remove sulfur will also saturate some of the olefinic compounds in the fraction reducing the octane and causing a loss of source olefins.
[0013] Various proposals have been made for removing sulfur while retaining the more desirable olefins. Since the valuable olefins in the cracked naphtha are mainly in the low boiling fraction of these naphthas and the sulfur containing impurities tend to be concentrated in the high boiling fraction the most common solution has been prefractionation prior to hydrotreating. The conventional prefractionation produces a light boiling range naphtha which boils in the range of C 5 to about 250° F. and a heavy boiling range naphtha which boils in the range of from about 250-475° F.
[0014] The predominant light or lower boiling sulfur compounds are mercaptans while the heavier or higher boiling compounds are thiophenes and other heterocyclic compounds. The separation by fractionation alone will not remove the mercaptans. However, in the past the mercaptans have been removed by oxidative processes involving caustic washing. A combination oxidative removal of the mercaptans followed by fractionation and hydrotreating of the heavier fraction is disclosed in U.S. Pat. No. 5,320,742. In the oxidative removal of the mercaptans the mercaptans are converted to the corresponding disulfides.
[0015] U.S. Pat. No. 5,597,476 discloses a two-step process in which naphtha is fed to a first distillation column reactor which acts as a depentanizer or dehexanizer with the lighter material containing most of the olefins and mercaptans being boiled up into a first distillation reaction zone where the mercaptans are reacted with diolefins to form sulfides which are removed in the bottoms along with any higher boiling sulfur compounds. The bottoms are subjected to hydrodesulfurization in a second distillation column reactor where the sulfur compounds are converted to H 2 S and removed.
SUMMARY OF THE INVENTION
[0016] Briefly a light cracked naphtha (LCN) is fractionated and a higher boiling naphtha fraction (about 165-350° F.) of light cracked naphtha (LCN) is fed, along with hydrogen, to a distillation column reactor along with some heavy cracked naphtha (HCN) boiling in the range of 350-450° F. The distillation column reactor contains a standard hydrodesulfurization catalyst which causes the organic sulfur compounds (mercaptans, sulfides and thiophenes) to react with the hydrogen to form hydrogen sulfide. The HCN is used as a solvent so that the distillation column reactor may be operated at higher temperatures and still have boiling material in the catalyst bed. In addition it continuously washes the catalyst to remove coke build up and extend catalyst life.
[0017] The HCN is removed as bottoms and recycled to the distillation column reactor while the now hydrodesulfurized higher boiling naphtha fraction of the LCN, is taken as overheads along with unreacted hydrogen and hydrogen sulfide where the hydrogen sulfide is removed.
[0018] In a preferred embodiment a light cracked naphtha (LCN) is subjected to a two-stage process for the removal of organic sulfur first by thioetherification and fractionation of a heavier fraction which is then subjected to hydrodesulfurization. In the first stage the light naphtha boiling in a range of about C 5 -350° F. is subjected to thioetherification, more preferably in a distillation column reactor wherein most of the mercaptans are reacted with the diolefins to produce sulfides. In addition the distillation column reactor acts as a splitter taking a lower boiling range naphtha fraction (about C 5 -165° F.) overhead which is substantially reduced in total sulfur content, especially the mercaptans. A higher boiling naphtha fraction (about 165-350° F.) is taken as bottoms which includes the sulfides made in the reactor.
[0019] The bottoms are fed, along with hydrogen, to a distillation column reactor along with some heavy cracked naphtha HCN boiling in the range of 350-450° F. In the more preferred embodiment the second distillation column reactor contains a standard hydrodesulfurization catalyst which causes the organic sulfur compounds (mercaptans, sulfides and thiophenes) to react with the hydrogen to form hydrogen sulfide. As noted the HCN is used as a solvent so that the distillation column reactor may be operated at higher temperatures and still have boiling material in the catalyst bed, while continuously washing the catalyst to remove coke build up and extend catalyst life. The HCN is removed as bottoms and recycled to the distillation column reactor while the now hydrodesulfurized higher boiling naphtha fraction of the LCN from the first reactor, is taken as overheads along with unreacted hydrogen and hydrogen sulfide where the hydrogen sulfide is removed. The higher boiling fraction may then be mixed back with the lower boiling naphtha fraction from the first reactor to produce a low sulfur product.
[0020] The HCN which is recycled eventually is substantially desulfurized and the olefins contained therein are hydrogenated to produce a clean solvent.
[0021] As used herein the term “distillation column reactor” means a distillation column which also contains catalyst such that reaction and distillation are going on concurrently in the column. In a preferred embodiment the catalyst is prepared as a distillation structure and serves as both the catalyst and distillation structure. As used herein the term “distillation reaction zone” means the area within a distillation column reactor.
[0022] The terms “lower boiling” and “higher boiling” are relative to the full boiling LCN material. As in any fractional distillation a lower material is taken overhead and a higher boiling material is taken as bottoms. The boiling points may be adjusted to obtain the desired degree of thioetherification and desulfurization.
BRIEF DESCRIPTION OF THE DRAWING
[0023] The figure is a flow diagram in schematic form of the preferred embodiment of the invention.
DETAILED DESCRIPTION
[0024] The feed to the process comprises a sulfur-containing petroleum fraction from a fluidized bed catalytic cracking unit (FCCU) which boils in the light gasoline boiling range (C 5 to about 350° F.) which is designated light cracked naphtha or LCN. Generally the process is useful on the naphtha boiling range material from catalytic cracker products because they contain the desired olefins and unwanted sulfur compounds. Straight run naphthas have very little olefinic material, and unless the crude source is “sour”, very little sulfur.
[0025] The sulfur content of the catalytically cracked fractions will depend upon the sulfur content of the feed to the cracker as well as the boiling range of the selected fraction used as feed to the process. Lighter fractions will have lower sulfur contents than higher boiling fractions. The front end of the naphtha contains most of the high octane olefins but relatively little of the sulfur. The sulfur components in the front end are mainly mercaptans and typical of those compounds are: methyl mercaptan (b.p. 43° F.), ethyl mercaptan (b.p. 99° F.), n-propyl mercaptan (b.p. 154° F.), iso-propyl mercaptan (b.p. 135-140° F.), iso-butyl mercaptan (b.p. 190° F.), tert-butyl mercaptan (b.p. 147° F.), n-butyl mercaptan (b.p. 208° F.), sec-butyl mercaptan (b.p. 203° F.), isoamyl mercaptan (b.p. 250° F.), n-amyl mercaptan (b.p. 259° F.), α-methylbutyl mercaptan (b.p. 234° F.), α-ethylpropyl mercaptan (b.p. 293° F.), n-hexyl mercaptan (b.p. 304° F.), 2-mercapto hexane (b.p. 284° F.), and 3-mercapto hexane (b.p. 135° F.). Typical sulfur compounds found in the heavier boiling fraction include the heavier mercaptans, thiophenes sulfides and sulfides.
[0026] Thioetherification
[0027] The reaction of mercaptans with diolefins to produce sulfides herein is termed thioetherification. A suitable catalyst for the reaction of the diolefins with the mercaptans is 0.4 wt % Pd on 7 to 14 mesh Al 2 O 3 (alumina) spheres, supplied by Sud-Chemie (formerly United Catalyst Inc.), designated as G-68C. Typical physical and chemical properties of the catalyst as provided by the manufacturer are as follows:
TABLE I Designation G-68C Form Sphere Nominal size 7 × 14 mesh Pd. wt % 0.4 (0.37-0.43) Support High purity alumina
[0028] Another catalyst useful for the mercaptan-diolefin reaction is 58 wt % Ni on 8 to 14 mesh alumina spheres, supplied by Calcicat, designated as E-475-SR. Typical physical and chemical properties of the catalyst as provided by the manufacturer are as follows:
TABLE II Designation E-475-SR Form Spheres Nominal size 8 × 14 Mesh Ni wt % 54 Support Alumina
[0029] Hydrogen is provided as necessary to support the reaction and to reduce the oxide and maintain it in the hydride state. The distillation column reactor is operated at a pressure such that the reaction mixture is boiling in the bed of catalyst. A “froth level” may be maintained throughout the catalyst bed by control of the bottoms and/or overheads withdrawal rate which may improve the effectiveness of the catalyst thereby decreasing the height of catalyst needed. As may be appreciated the liquid is boiling and the physical state is actually a froth having a higher density than would be normal in a packed distillation column but less than the liquid without the boiling vapors.
[0030] The present process preferably operates at overhead pressure of said distillation column reactor in the range between 0 and 250 psig and temperatures within said distillation reaction zone in the range of 100 to 300° F., preferably 130 to 270° F.
[0031] The feed and the hydrogen are preferably fed to the distillation column reactor separately or they may be mixed prior to feeding. A mixed feed is fed below the catalyst bed or at the lower end of the bed. Hydrogen alone is fed below the catalyst bed and the hydrocarbon stream is fed below the bed to about the mid one-third of the bed. The pressure selected is that which maintains catalyst bed temperature between 100° F. and 300° F.
[0032] Hydrodesulfurization
[0033] The reaction of organic sulfur compounds in a refinery stream with hydrogen over a catalyst to form H 2 S is typically called hydrodesulfurization. Hydrotreating is a broader term which includes saturation of olefins and aromatics and the reaction of organic nitrogen compounds to form ammonia. However hydrodesulfurization is included and is sometimes simply referred to as hydrotreating.
[0034] Catalysts which are useful for the hydrodesulfurization reaction include Group VIII metals such as cobalt, nickel, palladium, alone or in combination with other metals such as molybdenum or tungsten on a suitable support which may be alumina, silica-alumina, titania-zirconia or the like. Normally the metals are provided as the oxides of the metals supported on extrudates or spheres and as such are not generally useful as distillation structures.
[0035] The catalysts may additionally contain components from Group V and VIB metals of the Periodic Table or mixtures thereof. The use of the distillation system reduces the deactivation and provides for longer runs than the fixed bed hydrogenation units of the prior art. The Group VIII metal provides increased overall average activity. Catalysts containing a Group VIB metal such as molybdenum and a Group VIII such as cobalt or nickel are preferred. Catalysts suitable for the hydrodesulfurization reaction include cobalt-molybdenum, nickel-molybdenum and nickel-tungsten. The metals are generally present as oxides supported on a neutral base such as alumina, silica-alumina or the like. The metals are reduced to the sulfide either in use or prior to use by exposure to sulfur compound containing streams.
[0036] The properties of a typical hydrodesulfurization catalyst are shown in Table III below.
TABLE III Manufacture Criterion Catalyst Co. Designation DC-130 Form Trilobe Nominal size 1.3 mm diameter Metal, Wt. % Cobalt 3.4 Molybdenum 13.6 Support Alumina
[0037] The catalyst typically is in the form of extrudates having a diameter of ⅛, {fraction (1/16)} or {fraction (1/32)} inches and an UD of 1.5 to 10. The catalyst also may be in the form of spheres having the same diameters. In their regular form they form too compact a mass and are preferably prepared in the form of a catalytic distillation structure. The catalytic distillation structure must be able to function as catalyst and as mass transfer medium. Catalytic distillation structures useful for this purpose are disclosed in U.S. Pat. Nos. 4,731,229, 5,073,236, 5,431,890 and 5,266,546 which are incorporated by reference.
[0038] The distillation column reactor is advantageously used to react the heavier or higher boiling sulfur compounds. The overhead pressure is maintained at about 0 to 350 psig with the corresponding temperature in the distillation reaction zone of between 450 to 700° F. Hydrogen partial pressures of 0.1 to 70 psia, more preferably 0.1 to 10 are used, with hydrogen partial pressures in the range of 0.5 to 50 psia giving optimum results.
[0039] The operation of the distillation column reactor results in both a liquid and vapor phase within the distillation reaction zone. A considerable portion of the vapor is hydrogen while a portion is vaporous hydrocarbon from the petroleum fraction. Actual separation may only be a secondary consideration.
[0040] Without limiting the scope of the invention it is proposed that the mechanism that produces the effectiveness of the present process is the condensation of a portion of the vapors in the reaction system, which occludes sufficient hydrogen in the condensed liquid to obtain the requisite intimate contact between the hydrogen and the sulfur compounds in the presence of the catalyst to result in their hydrogenation. In particular, sulfur species concentrate in the liquid while the olefins and H 2 S concentrate in the vapor allowing for high conversion of the sulfur compounds with low conversion of the olefin species.
[0041] The result of the operation of the process in the distillation column reactor is that lower hydrogen partial pressures (and thus lower total pressures) may be used. As in any distillation there is a temperature gradient within the distillation column reactor. The temperature at the lower end of the column contains higher boiling material and thus is at a higher temperature than the upper end of the column. The lower boiling fraction, which contains more easily removable sulfur compounds, is subjected to lower temperatures at the top of the column which provides for greater selectivity, that is, less hydrocracking or saturation of desirable olefinic compounds. The higher boiling portion is subjected to higher temperatures in the lower end of the distillation column reactor to crack open the sulfur containing ring compounds and hydrogenate the sulfur.
[0042] Referring now to the figure there is shown a schematic flow diagram of one embodiment of the invention.
[0043] A light cracked naphtha is fed to a thioetherification reactor 10 containing a bed of thioetherification catalyst 12 through flow line 101 with hydrogen being fed through flow line 115 . The thioetherification reactor is configured to act as a light naphtha splitter. The mercaptans in the LCN are reacted with the diolefins to form higher boiling sulfides. A lower boiling fraction substantially reduced in mercaptans is removed as overheads via flow line 102 . A higher boiling fraction containing the sulfides, some unreacted mercaptans and higher boiling sulfur compounds, such as thiophene, is taken as bottoms via flow line 103 .
[0044] The bottoms, or higher boiling fraction, from the thioetherification reactor 10 in flow line 103 are combined with a HCN and fed via flow line 105 to a hydrodesulfurization reactor 20 having beds 22 and 24 of hydrodesulfurization catalyst. The ratio of LCN to HCN in the feed to the hydrodesulfurization reactor can be in the range of 2:1 to 4:1 In the hydrodesulfurization reactor the organic sulfur compounds including sulfides, mercaptans and thiophene, are reacted with hydrogen to produce hydrogen sulfide. In addition the higher boiling fraction of the LCN is distilled overhead via flow line 110 along with the unreacted hydrogen and the hydrogen sulfide. The hydrogen sulfide and hydrogen are separated from the overheads in a separator 30 and removed via flow line 111 . The liquid is removed from the separator 30 via flow line 112 and recombined with the lower boiling fraction in flow line 102 to produce a product having a reduced total sulfur content.
[0045] If desired the overheads in flow line 110 may be subjected to further subjected to hydrodesulfurization in a polishing reactor which is not shown.
[0046] The HCN is removed from the hydrodesulfurization reactor 20 as bottoms via flow line 107 and a small purge is taken via flow line 108 . The remainder of the HCN bottoms is recycled via flow line 109 with make up HCN in flow line 104 . As the HCN is recycled the sulfur content is reduced and the olefins are saturated in the lower catalyst bed 24 which provides a clean solvent. The clean solvent provides a washing action which removes coke and other detrimental products from the catalyst which greatly increases the catalyst life. As may be noted in the following example the observed rate constant for the conversion of sulfur actually increased during operation. If desired a catalyst which has enhanced hydrogenation properties, such as nickel and molybdenum oxides on an alumina support may be used in the lower which will speed up the hydrogenation of the olefines in the HCN.
EXAMPLE
[0047] In the following example presented in tabular form below the lower boiling fraction from a thioetherification reactor/splitter is fed along with HCN to a hydrodesulfurization reactor between two beds containing hydrodesulfurization catalyst.
Feeds ASTM D-3710 LCN HCN IBP 146 382 5% 161 394 10% 173 401 20% 191 409 50% 235 431 80% 295 447 90% 328 460 95% 341 491 EP 381 515 Total S (ppm) 598 5.9 Conditions and results Time on stream, hrs 354 LCN feed rate, lb//hr 40.0 HCN feed rate, lb/hr 10.0 Mixed Sulfur content, wppm 480 % feed flashed 39.9 Liquid feed temp, ° F. 498.5 Hydrogen rate, SCFH 81 Sulfur in LCN Converted, %* 97.07 Bromine No. in LCN Converted, %* 33.76 Final Bromine No. 48.5 Final total Sulfur, wppm 23.5 OH recovery, % of mixed feed 83.98 H 2 Conversion, % 30.70 H 2 Consumed, SCF/BBL 166 Est. H 2 Concentration in Vapor at top 0.1389 Est. H 2 Concentration in Vapor at bottom 0.2913 Overhead pressure, psig 210 Throughput, bbl/day/ft. 3 2.29 Upper bed temp., ° F. 513 Lower bed temp., ° F. 598 R + M/2 loss 3.5 R loss 5.1 M loss 1.9 Observed rate constant at beginning of run 0.025 Observed rate constant at end of run 0.032 | A process for the treatment of a light cracked naphtha is disclosed wherein the light cracked naphtha is first subjected to thioetherification and fractionation into two boiling fractions. The lower boiling fraction is removed as overheads for later recombination with the product and the higher boiling fraction is combined with a heavy cracked naphtha and subjected to simultaneous hydrodesulfurization and fractionation to separate the higher boiling fraction from the heavy cracked naphtha which is recycled. The recycled heavy cracked naphtha is eventually desulfurized and hydrogenated to produce a clean solvent which washes the catalyst and extends catalyst life. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority in U.S. Provisional Patent Application No. 61/213,929, filed Jul. 30, 2009, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present disclosed technology relates generally to a rolled door installation device, and in particular a cradle for holding a rolled curtain door and a system for installing the door above an opening.
[0004] 2. Description of the Related Art
[0005] Curtain door systems for residential and commercial use provide a movable barrier to cover a window or opening in a wall. The door systems may be manufactured to cover windows or openings having a wide variety of widths and heights. Curtain door systems are used in a variety of applications such as preventing the spread of fire in occupied structures, providing security to protect windows and doorways, and to cover large openings in walls where the use of large paneled doors is cumbersome or impractical such as openings for the passage of vehicles.
[0006] A curtain door system generally includes a curtain door having a series of interlocking slats of metal or plastic that spans an opening. The curtain door mounts above an opening or window on mounting hardware, and during operation is guided into position by guide rails at the periphery of the opening. The mounting hardware may include a pipe or drum that rotates between two head plates, and from which the curtain door is suspended. The interlocking feature of the slats allows the curtain door to be rolled about the pipe or drum when opening or closing the curtain door. Manufacturers typically ship curtain doors with the curtain door wound about the pipe or drum, or connected to the mounting hardware and drive mechanism. However, installation of the curtain door may be performed after installation of the guide rails, pipe, mounting hardware, and drive mechanism.
[0007] Rolled curtain doors are often heavy and awkward to install. Conventional installation methods require suspending the rolled curtain door below the pipe using slings or ropes. Workers pull on the ropes to lift the door up to the pipe for attachment. Workers next ascend ladders and manually adjust the orientation of the rolled door to align the top slat with the pipe, and connect the two. The curtain door is then rolled off of the ropes and onto the pipe. As a result, the conventional tools and process used to install curtain doors is fraught with challenges, especially when installing doors that weigh hundreds of pounds, or used to cover large openings having great height or width. Moreover, the conventional installation process can lead to injury of the workers installing the door because of a need to use body strength and ladders to complete installation. Therefore, there is a need for a curtain door installation system that permits a worker to safely and accurately install a curtain door regardless of the height of the opening the door will cover, and the size and weight of the door.
[0008] Therefore, those who install curtain door systems desire an installation tool that provides an efficient and safe method for installing these systems. The disclosed subject matter provides these features and advantages.
SUMMARY OF THE INVENTION
[0009] In accordance with the invention, a rolled curtain door may be supported by an adjustable cradle having rollers, that are configured to support the curtain door and permit rolling of the door thereon to aid in mounting the door to mounting hardware. The cradle has extensions with rollers that may be extended, thereby allowing the cradle to support rolled curtain doors of varying length. The cradle may be mounted on the tines of a fork on a lifting device, such as a forklift or lifting assembly, to raise raising the curtain door up to a mounting position on a wall above a door opening. Optionally, the rollers may be powered by a motor to rotate the door and assist in mounting it to door hardware.
[0010] If desired, particular embodiments may optionally include a lift assembly attached to the cradle. The lift assembly includes a tower extendable by a piston and cylinder unit. The tower has a fork with tines projecting therefrom. The tower is attached to a base having casters for manually rolling the cradle and lift assembly around a worksite. Stabilizers on the base may be used to support and level the assembly when in use. A winch motor with a cable is attached to the tower and may be used to assist in loading a rolled curtain door onto the cradle. Optionally, a hoist attached to the tower may be used to load a rolled curtain door onto the cradle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The drawings constitute a part of this specification and include exemplary embodiments of the disclosed subject matter illustrating various objects and features thereof, wherein like references are generally numbered alike in the several views.
[0012] FIG. 1 is a rear perspective view of a first alternative embodiment curtain door installation system embodying principles of the disclosed subject matter where a cradle supporting a rolled curtain door is attached to, and elevated by, a lifting device.
[0013] FIG. 2 is a rear perspective view of the curtain door installation system embodying principles of the disclosed subject matter showing the cradle with extensions assemblies extended from a central assembly.
[0014] FIG. 3 is a front elevational view of the cradle attached to a lifting device.
[0015] FIG. 4 is a second alternative embodiment curtain door installation system including a cradle attached to a lift with an integrated hoist.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] As required, detailed aspects of the disclosed subject matter are disclosed herein; however, it is to be understood that the disclosed aspects are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art how to variously employ the present invention in virtually any appropriately detailed structure.
[0017] Certain terminology will be used in the following description for convenience in reference only and will not be limiting. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning
[0018] Referring to the drawings in more detail, the reference numeral 101 generally designates a curtain door installation system embodying the principles of the disclosed subject matter. Referring to FIG. 2 , the system 101 generally includes a cradle 102 having a central assembly 104 , and first and second extension assemblies 152 and 154 . By way of example, and not to be construed as limiting, the system 101 is shown in FIG. 1 attached to a lift assembly 202 , and elevated, for installing the rolled curtain door 310 above an opening 302 in a wall 304 . A rolled door system generally includes a curtain door 310 attached to a pipe or drum located between two head plates 306 , a drive mechanism for raising and lowering the curtain door 310 , and guide rails for keeping the curtain door 310 aligned with the opening during operation.
[0019] Referring to FIG. 2 , cradle 102 generally comprises a central assembly 104 , and first and second extension assemblies 152 and 154 . Central assembly 104 includes a cross member 106 having a pair of fork sleeves 108 secured to the underside, and two roller assemblies 114 secured to the top. Cross member 106 may comprise a hollow steel tube with opposite open ends, and having a rectangular cross section for slidably receiving a leg 156 of first or second extension assemblies 152 and 154 . Cross member 106 is the part that supports the roller assemblies 114 , and for mounting first and second extension assemblies 152 and 154 . Fork sleeves 108 comprise a steel tube having a rectangular cross section, and dimensioned to slidably receive the tines of a fork from a lifting device including, but not limited to, lift assembly 202 , a forklift or a lift truck (not shown). Each fork sleeve 108 has an aperture 110 for receiving a locking member such as a locking pin or a set bolt 112 to secure cradle 102 to the fork of the lifting device. Alternatively, fork sleeves 108 may be welded to the fork.
[0020] Each roller assembly 114 includes an arm 116 mounting two rollers that are opposite each other and allow free rotation of the roller thereon. The roller may include, but is not limited to, a metal, plastic, or composite drum, wheel, or tube, preferably a wheel 120 having a rubber contact surface. Wheels 120 are mounted on arm 116 by a vertical support 115 , wherein the rotational axis of wheel 120 is perpendicular to arm 116 , and wheel 120 is spaced a sufficient distance apart as to cradle a rolled curtain door 310 . Although a wheel 120 is shown and described, any suitable roller or rollers may be used with cradle 102 that permits free rotation of the rolled curtain door 310 thereon. Roller assemblies 114 are mounted with arm 116 perpendicular to cross member 106 , thereby supporting rolled curtain door 310 parallel to cross member 106 . The fork sleeves 108 , cross member 106 , vertical support 115 , and roller assemblies 114 are secured by welding, or alternatively, by fasteners such as a nut and bolt combination.
[0021] Cradle 102 may suitably function with or without first and second extension assemblies 152 and 154 . Extension assemblies 152 and 154 may be connected to central assembly 104 when supporting an especially wide or heavy curtain doors 310 . First extension assembly 152 includes leg 156 mounting roller assembly 114 at one end. Leg 156 comprises a solid or hollow steel tube having a rectangular cross section adapted for insertion into cross member 106 . Roller assembly 114 may be secured to leg 156 by a pair of U-bolts 158 , nuts 160 , and a plate 162 , or alternatively by welding.
[0022] Second extension assembly 156 is generally identical to first extension assembly 152 and therefore will not be described. Leg 146 end opposite roller assembly 114 is inserted into the open end of cross member 106 with roller assembly 114 facing up, and are slid in and out as needed to position first and second roller assemblies 114 under the rolled curtain door 310 .
[0023] Cradle 102 may optionally be powered by a motor 276 that can rotate wheels 120 thereby rotating the rolled curtain door 310 thereon when mounting the curtain door 310 above an opening. Roller assemblies on cross member 106 may be connected by a shaft 174 having a driven sprocket 172 . Driven sprocket 172 is connected to a drive sprocket 176 on motor 276 by a chain 178 . Motor 276 is mounted on either lift assembly 202 or cross member 106 , preferably lift assembly 202 . Motor 276 may be an electrical motor powered by a suitable electrical power supply, or a hydraulic motor powered by an complimentary power source.
[0024] In use, cradle 102 is mated to a lifting device having a pair of forks projecting therefrom. The forks are inserted into fork sleeves 108 , and cradle 102 is secured to the forks by tightening set bolts 112 in apertures 110 . First and second extension assemblies 152 and 154 are adjusted or removed, as needed, to properly support a rolled curtain door 310 . A curtain door 310 is then loaded onto cradle 102 , and cradle 102 is then raised up to the proper height above an opening where the rolled curtain door 310 is attached to the installed door mounting hardware such as a pipe or drum. After the rolled curtain door 310 is attached to the mounting hardware, roller assemblies 114 allow free rotation of the curtain door 310 off of the cradle 102 as the curtain door 310 is rolled onto the pipe or drum, or motor 276 may be engaged to rotate wheels 120 to assist in transferring the rolled curtain door 310 to the door mounting hardware.
[0025] Occasionally a rolled curtain door 310 may already be attached to mounting hardware and a drive mechanism. Therefore, although a rolled curtain door 310 is described, cradle 102 may be used to install a rolled curtain door above a doorway when the rolled curtain door already has its mounting hardware installed using the same process describe above.
[0026] Supporting the rolled curtain door 310 with cradle 102 , and using roller assemblies 114 to transfer the curtain door 310 to the mounting hardware avoids the perils previously encountered when installing curtain doors. Namely, workers can avoid use of straps, step ladders, and body strength currently necessary to suspend and raise heavy curtain door below its mounting hardware. This provides workers with a tool to safely and accurately install a curtain door regardless of the height or location of the mounting hardware, and the size or weight of the door.
[0027] A curtain door installation system comprising a first alternative embodiment curtain door installation system 201 is shown in FIGS. 1 and 2 , and includes a cradle 102 attached to lift assembly 202 . Lift assembly generally comprises a tower 252 connected to a base 204 . The generally rectangular base 204 includes a frame 206 constructed of tubular members having a rectangular cross section. Frame 206 comprises a rectangle having front and rear members 208 and 210 , and interconnecting side members 212 and 214 . The ends of front and rear members 208 and 210 are joined to their respective side members 212 and 214 in a conventional manner such as by welding. Base 204 is supported by casters 216 secured to frame 206 allowing lift assembly 202 to be rolled around a worksite by a worker.
[0028] A deck 218 is secured to frame 206 and provides a mounting surface for two deck ribs 220 . Each deck rib 220 is located on top of deck 218 adjacent to a side member 212 and 214 . Ribs 220 comprise a solid or hollow steel tube having a rectangular cross section, and traverse deck 218 from front to back adding rigidity to base 204 . The front and rear of each rib 220 provides a mounting surface for a stabilizer 222 used to bias against the surface supporting lift assembly 202 , thereby stabilizing and holding lift assembly 202 when in use. Stabilizer 222 may be a conventional manually-operated stabilizer, or a mechanical stabilizer operated using electric or hydraulic power.
[0029] Tower 252 generally comprises an extendable mast 254 that raises and lowers a fork 266 . Mast 254 is centered at the rear of base 204 and secured thereto by welding. Mast 254 is further secured to base 204 by a heel 256 that is secured to both deck 218 and mast 254 by welding, completing formation of a rigid box-like structure that adds further stability to the connection between base 204 and mast 254 . Mast 254 is further stabilized by angular trusses 260 secured to mast 254 at one end, and base 204 at the other end by welding. A handle 262 on the rear of each truss 260 permits a worker to manually maneuver lift assembly 202 .
[0030] Mast 254 comprises interlocking rails supporting a carriage 264 and a forward-facing fork 266 . Mast 254 functions in a similar manner as those found on a forklift truck for raising and lowering carriage 264 and fork 266 . Mast 254 is raised and lowered by a piston and cylinder unit (p-c unit) 268 connected at one end to base 204 and at another end to mast 254 by a chain. P-c unit 268 communicates with a reservoir 270 via a valve 272 and hose 274 . P-c unit 268 may function using a pneumatic system or a hydraulic system, preferably a pneumatic system. Actuation of valve 272 to a first position extends p-c unit 268 and raises fork 266 . Actuation of valve 272 to a second position ceases movement of p-c unit 268 . Actuation of valve 272 to a third position withdraws p-c unit 268 and lowers fork 266 .
[0031] A winch motor 226 winds-up and lets out a cable 228 having a hook 230 for connecting to a rolled curtain door 310 . Cable 228 passes through a guide 232 keeping cable 228 aligned with winch motor 226 and a wheel 234 disposed at the top of the mast 254 . Wheel 234 allows for cable 228 to roll on when lifting a rolled curtain door 310 onto cradle 102 .
[0032] In use, curtain door installation system 201 provides for installation of a rolled curtain door 310 without the need of a forklift truck. Cradle 102 is attached to fork 266 of the lift assembly 202 in the same manner as described above. First and second extension assemblies 152 and 154 are adjusted or removed as needed depending on the size or weight of the rolled curtain door 310 . After loading a rolled curtain door 310 onto cradle 102 using cable 228 and winch 226 , lift assembly 202 may be freely rolled across a surface. Using handles 262 , a worker can manually position lift assembly 202 and curtain door 310 below an opening to be covered. After engaging stabilizers 222 to immobilize and level lift assembly 202 , a worker actuates valve 272 to the first position to raise fork 266 and cradle 102 . When cradle 102 has reached the proper height to offload the rolled curtain door 310 to the mounting hardware, valve 272 is moved to the second position stopping movement of cradle 102 . After the curtain door 310 is offloaded, valve 272 is moved to the third position permitting cradle 102 to be lowered to the ground.
[0033] A curtain door installation system comprising a second alternative embodiment curtain door installation system 401 is shown in FIG. 4 , and includes cradle 102 and lift assembly 202 as described above, and further including hoist 402 . Hoist 402 is attached to the top of tower 252 for assisting in loading a rolled curtain door 310 onto cradle 102 . Hoist 402 generally includes a boom 404 that pivots atop tower 252 , and a p-c unit 418 for raising and lowering boom 404 . Boom 404 extends forward from the rear of lift assembly 202 across the top of tower 252 , terminating in front of lift assembly 202 . Boom 404 may comprise a hollow steel tube having a rectangular cross section. Boom 404 pivots about a bracket 408 extending from the top of tower 252 . P-c unit 418 attaches at one end to the rear of boom 404 , and at another end to tower 252 . P-c unit 418 may function in a similar manner, and use like components, as p-c unit 268 described above. A hook 406 at the forward end of boom 404 allows for connection of a chain 410 . Straps 414 may be wrapped around the rolled curtain door 310 and connected to the free end of chain 410 by a cable 412 . Optionally, electrically-powered lights 416 may be attached to tower 252 providing illumination of cradle 102 and workspace.
[0034] In use, the rolled curtain door 310 is connected to the hoist 402 as described above. Actuation of p-c unit lifts the rolled curtain door 310 off of the ground or a vehicle. Workers may then guide the rolled curtain door 310 over cradle 102 and lower boom 404 thereby placing the door 310 between wheels 120 of the cradle 102 . Rolled curtain door 310 is then disconnected from hoist 402 , and raised into position on cradle 102 for installation.
[0035] It will be appreciated that the components of cradle 102 and installation systems 101 , 201 , and 401 may be used for various other applications. Moreover, cradle 102 and installation systems 101 , 201 , and 401 may be fabricated in various sizes and from a wide range of suitable materials, using various manufacturing and fabrication techniques.
[0036] It is to be understood that while certain aspects of the disclosed subject matter have been shown and described, the disclosed subject matter is not limited thereto and encompasses various other embodiments and aspects. | A cradle for supporting and installing a rolled curtain door comprises rollers configured to support, and permit rolling, of a rolled curtain door thereon. Extensions with rollers permit the cradle to support rolled curtain doors of varying length. A motor may be connected to the rollers to assist in rotating the door. The cradle may be mounted on the tines of a fork on a lifting device. A lift assembly having a tower and base may be attached to the cradle for manually positioning, and mechanically elevating the cradle and door when installing the door. The tower is extended by a piston-and-cylinder unit. A winch motor and cable, or a boom hoist attached to the tower may be used to load a door onto the cradle. | 4 |
The present invention relates to a sediment capping method and system. In one aspect the present invention relates to an improved broadcast sediment capping method. In another aspect, the invention relates to an improved sub-aquatic contaminated sediment capping system.
BACKGROUND OF THE INVENTION
Sub-aquatic contaminated sediments often represent a harmful and long term source of pollutants to the environment. A variety of approaches, such as dredging, have been used for the treatment of contaminated sediments, but they are expensive and can have limited value. Due to the increased volume of contaminated sediment cleanup projects both in the U.S. and abroad, sediment capping has become an option. In many areas the removal of material from a water body is not cost effective. In-situ capping of contaminated sediment is an efficient alternative that can have an immediate beneficial impact on the environment, as the contaminated sediment is isolated from aquatic organisms. Furthermore, capping contaminated sediments generally creates an anaerobic environment which permits natural degradation processes, which provide an opportunity for destruction and detoxification of harmful contaminants. Sediment capping has been used to contain harmful contaminants, including pesticides, metals, volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), and polynuclear aromatic hydrocarbons (PAHs).
The capping of contaminated sediments is designed to prevent the upward migration of residual contaminants and/or to provide a clean subsurface bed of sediment that can be colonized by uncontaminated organisms. Capping alone could be used as a strategy to eliminate the need for dredging or could be used in conjunction with dredging to cover dredged locations with a clean layer of material where target clean-up goals cannot be achieved.
Previous methods of capping contaminated sediments have often involved mechanical equipment using buckets or direct slurry discharge into a water body. The mechanical bucket method often requires dumping large volumes of capping material into the water using a variety of buckets, including a clamshell bucket or dragline bucket. After releasing a bucket load it falls through a water column often as a distinct mass, which usually comes to rest on top of the contaminated material. This method has had some success in deep water producing caps with designed thickness over 12″. The water depth allows the capping material to disperse somewhat reducing velocity and concentration as it travels downward through the water. The thick cap design then accommodates the placement inaccuracies inherent in mechanical bucket placement.
The mechanical bucket method poses problems for relatively shallow water depth capping. When the mechanical bucket method is used to install thin layer caps (3″ to 12″), especially in shallow water (less than 10′), the results are often problematic. The capping material travels a relatively short distance through the water, thus causing its weight and velocity to displace the soft contaminated sediments. Displacement of the contaminated sediment is adverse to the purpose and goals of sediment capping. Furthermore, bucket placement of capping material leaves uneven mounds, which must then be raked in order to produce the proper thickness. This raking action often disturbs the underlying sediments, thereby causing sediment mixing and re-suspending of both the capping material and the contaminated sediments. The raking step can result in low production rates and capping material waste, and therefore higher production costs. In addition, bucket placement requires deep vessel draft requirements and cannot be employed in relatively shallow operations.
An alternative known capping method involves the open water slurry discharge method. Due to the large volume of water needed to transport the sand or gravel material this method also tends to displace the soft underlying material needing to be capped. Another problem with this method is that it requires sand or gravel slurry to be directly placed in water which raises turbidity levels. It would be advantageous for a sediment capping process to provide delivery of granular material from shallow draft vessels at relatively high rates of production with minimal disturbance of the sub-aquatic sediment.
SUMMARY OF THE INVENTION
In one embodiment, the invention is a sediment capping system having a spreader barge comprising a capping material spreading means and a spreader pool where the spreading means is configured to distribute capping material into the spreader pool. The system also includes a template barge for guiding the spreader barge while the capping material is distributed to a sub-aquatic sediment. The spreader barge and the template barge include a positioning means. The system further includes a capping material providing means, wherein the capping material is received by the intake means and distributed by the spreading means.
In another embodiment, the invention is a sediment capping system comprising a spreader barge for distributing a capping material over contaminated sub-aquatic sediment, a template barge configured to guide the movement of the spreader barge during distribution of the capping material, and a sub-aquatic elevation measuring means. The capping material distribution has limited disturbance of the sediment and the measuring means can acquire real-time elevation data.
In yet another alternative embodiment, the invention is a method for capping sub-aquatic sediment including identification of a sub-aquatic region for distributing a layer of capping material and providing a source of capping material to a capping system. The capping system includes a template barge, a spreader barge, and a broadcast spreader means. The template barge guides the spreader barge along a pre-determined path while capping material is distributed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a broadcast spreader in accordance with at least one embodiment of the present invention.
FIG. 2 is a side view of the broadcast spreader according to FIG. 1 .
FIG. 3 is a hopper for distributing and metering particulate matter in accordance with at least one embodiment of the present invention.
FIG. 4 is a block diagram representing a process for sub-aquatic capping in accordance with at least one embodiment of the present invention.
FIG. 5 is a side perspective view of the spreading means in accordance with at least one embodiment of the present invention.
FIG. 6 is a perspective view of a capping material distribution spinner in accordance with at least one embodiment of the present invention.
FIG. 7A is a perspective view of the spreading means in accordance with an alternative embodiment of the present invention.
FIG. 7B is a perspective view of the spreading means of FIG. 7A in use and depicting a spreading pattern, in accordance with an alternative embodiment of the present invention.
FIG. 8 is a perspective view of a capping material distribution spinner in accordance with an alternative embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2 , sediment capping system 10 is provided. System 10 includes spreader barge 12 , template barge 14 , and capping material providing means 16 . Spreader barge 12 includes capping material receiving means 18 , capping material shaker 20 , slurry water output 22 , capping material spreading means 24 , control center 26 , distribution pool 28 , capping material reservoir 29 and at least one positioning means 30 . Template barge 14 is releasably engaged with spreader barge 12 while the capping material is being distributed by spreader barge 12 . Barge 14 includes at least one positioning means 30 , fuel tank 32 , and barge movement means 34 . Spreader barge 12 and template barge 14 float on waterway surface 35 . The slurry enters the spreading barge 12 through the providing means 16 and is received by the receiving means 18 , which can be a hopper or alternative structure designed to receive capping material slurry. The shaker 20 separates the capping material from the water contained within the slurry. The water is evacuated through the slurry water output 22 and the capping material is distributed within the pool 28 by the spreading means 24 . While the barges 12 , 14 are floating on the waterway, the positioning means 30 , when deployed, prevents the barges 12 , 14 from laterally moving across the waterway. In at least one embodiment of the invention, the slurry water output 22 is a discharge pipe integrally connected to a liquid diffuser. As shown in FIGS. 1 and 2 , the positioning means 30 are positioning spuds.
Representative capping materials include but are not limited to sand, gravel, chipped stone, rocks, pebbles, and other solid particulate or granular matter suitable for sediment capping. By example, granular capping materials can range from about 0.1 mm to about 10 mm in size. Stones and rocks used for capping material can range from about ½ inch to about 2 inches. Capping material is transported through pipeline 16 , typically in the form of a slurry, and is received by spreader barge 12 at shaker 20 . Capping material slurry is the combination of water and solid capping material, which is more easily transported then dry capping material. An exemplary slurry includes a density of about 15% to about 20% by weight capping material. At this exemplary density range a capping material distribution production rate can range from about 60 to about 80 cubic yards per hour. Depending upon the type of capping material, the slurry density can be less than 15% by weight or greater than 20% by weight. Alternatively, the slurry can include granular additives suitable for use in sediment capping. Receiving means 18 can be a hopper or velocity box and is strategically selected based upon the configuration of providing means 16 , and the type of capping material used. In an alternative embodiment, providing means 16 can be a variety of capping material transportation means, such as barge transportation, airlift transportation, and extended conveyor transportation. The barge transported capping material can be fed into spreader barge 12 by bucket. This may be desirable when transport distances are excessive, or navigational concerns prevent delivery by slurry pipeline 16 .
Capping material shaker 20 processes the slurry by separating the capping material and the water. Water is gravitationally removed through the slurry water output 22 , which is a pipeline evacuated into distribution pool 28 . The output 22 can also include a water pump for quicker evacuation of the water. The slurry water often contains fine particulate matter. In an effort to avoid contamination of the waterway it is dispensed within distribution pool 28 . The distribution pool is a region of the water way confined by the barge 12 . Fine capping material pieces remain with the water while the capping material is removed within the shaker 20 . As the slurry water is evacuated it enters the pool, the remaining particles gradually sink to the sediment. Since the pool 28 is contained by the barge 12 , water currents and surface waves have less effect on the particles, thereby preventing them from dispersing through the water way. Alternatively, the slurry water can be filtered. The capping material is collected within a reservoir 29 and then distributed within the pool 28 by the distribution means 24 . Spreading means 24 can be a broadcast spreader and alternatively can be selected from a variety of spreader mechanisms. (See FIGS. 5 and 6 ). Distribution pool 28 is an open area configured to contain capping material as it is being distributed by the spreading means 24 in order to efficiently and accurately control capping material distribution to sediment layer 37 .
Movement of the spreader barge with respect to the template barge is performed by barge movement means 34 . Movement means 34 is an engine or winch operated by either a gas or electric fuel source. Engine 34 causes movement of spreader barge 14 with respect to template barge 12 . Additionally, when template barge 14 is re-positioned, movement means 34 causes movement of template barge 14 while spreader barge 12 is stationary. Alternatively, movement means 34 comprises a motor operated vehicle, by example, a wheel or caterpillar driven tractor or truck mounted on the template barge. In yet another alternative embodiment, both template barge 14 and spreader barge 12 include a fuel source 32 and movement means 34 .
At least one embodiment of the present invention includes distribution of capping material through slurry pipeline 16 . Referring to FIG. 3 , capping material conveyor 36 is provided for metering and distribution of capping material to spreader barge 12 through pipeline 16 . The conveyor 36 includes a metered hopper 38 into which capping material is loaded and a conveying means 39 configured for metered transportation of capping material to a slurry hopper. The capping material flows from the hopper 38 onto the conveying means 39 , which is situated beneath the hopper 38 . Loading the capping material into the conveyor 36 can be manual or through an automated conveyor means (not shown). Conveyor 36 then transfers capping material into a slurry hopper (not shown). The slurry hopper is a reservoir that has a water intake, a water overflow, and a slurry pump connected to slurry line 16 . The water intake receives water from a water source and combines the water and capping material within the slurry hopper to form a slurry. A combination of the water and dumping of capping material into the hopper from the conveyor 36 provides a mixing action which allows slurry formation. The slurry enters the pipeline 16 and is evacuated through pressure generated by the slurry pump. Excess water is removed through a water overflow pipeline, and is filtered prior to placement back into the waterway. A slurry pump provides a means for forcing the capping material slurry through pipeline 16 to spreader barge 12 . The feed rate of the capping material is metered by a feed opening and/or the variable speed of conveyor 36 . For the purpose of maintaining material balance, metering at the hopper loading location is important in order to assess the mass rate of delivery to spreader barge 12 . Long transport distances may require additional booster pumps (not shown) in order to maintain adequate slurry velocities. By example, slurry velocities for gravel slurry can range from about 10 feet per second (to about 12 feet per second. Gravel slurry velocities less than 10 feet per second and greater than 12 feet per second are contemplated. In at least one embodiment, system 10 is employed within a river having an extended region of contaminated sediment. Within this embodiment slurry pipeline 16 extends in excess of ½ mile. As spreader barge 12 moves farther away from land-based conveyor 36 , pipeline 16 is lengthened and booster pumps added to keep the slurry moving to spreader barge 12 .
System 10 allows capping material to be deposited evenly over underlying sediments, which can be soft, hard or a mixture of varying densities. One common use of the system is for “capping” contaminated sediments, and it is particularly well suited for shallow water placement of thin layer caps in an efficient manner over large areas with minimal disturbance of the contaminated sediment. Various embodiments of the present invention present a low-cost and environmentally friendly option for treating contaminated waterway sediments. Waterways include lakes, streams, rivers, flowages, reservoirs, and alternative open water sources. Embodiments of the present invention can be used in any water body, and particularly relatively shallow waterways where thin layer capping is required.
System 10 reduces costs relative to previously known capping methods by allowing rapid placement of capping material over large areas. In addition, various embodiments of the present invention allow tighter capping tolerances, which reduce the amount of capping material needed. This capping process allows for broadcast placement of sands and/or gravels for the purpose of in situ capping of contaminated sediments.
FIG. 4 is a block diagram representing a plurality of steps in the sediment capping process. A contaminated sediment region is identified at step 40 and the region is mapped at step 42 . Mapping step 42 includes identification of various capping variables, including the type of capping material to be employed, the distribution rate of the capping material, the size of distribution pool 28 , spreader barge 12 and template barge 14 movement sequence. After the region has been mapped, template barge 14 is positioned 44 at a distribution sequence starting position. Spreader barge 12 is then positioned 46 along side the template barge. At step 48 , the capping material is provided to spreader barge 12 and the capping material is distributed within pool 28 at step 50 . While the capping material is being distributed, the metering hopper and belt scale measure the weight of capping material distributed in real time. The weight measurements are compared to the predetermined capping material distribution amounts. As part of the verification process the sub-aquatic elevation of the capping material is measured at step 52 . This can be performed through manual coring to verify the cap thickness. A distribution decision is made at step 54 . If the proper amount of capping material was distributed, then the spreader barge changes its position at step 56 . If an inadequate amount of capping material was distributed, then step 50 is repeated. The rate and sequence timing of the capping material distribution can be automatically altered based upon coring data. The size of barges 12 , 14 and the size of pool 28 can determine the number of spreader barge 12 repositioning steps prior to repositioning of template barge 14 . A repositioning sequence includes the initial positioning of template barge 14 and subsequent step-like repositioning of spreader barge 12 . By example, the time for each spreader barge 14 “step” is in a range of about 2 minutes to about 5 minutes. The “step” time is dependant upon the production rate and the cap depth. The capping material is distributed during each spreader barge 12 step. In an alternative example, the spreader barge step is less than about 2 minutes or greater than about 5 minutes. After a set number of spreader barge 12 steps 56 , spreader barge 12 is positioned at step 58 . Template barge 14 is then repositioned at step 60 . Step 62 determines whether the capping process is complete. If more capping is required, then step 50 is repeated; otherwise the process is completed at step 64 .
Once the capping material is transported across the water body, via transportation barge, pipeline, or alternative means, it then enters spreader barge 14 . Barges 12 and 14 work in unison by walking on spuds 30 in a linear path parallel to one another. Spreader barge 12 , by example, is about 40 feet wide by about 80 feet long. Template barge 14 , by example, is about 20 feet wide and about 120 feet long. Both barges 12 and 14 have spuds 30 , which include hydraulic power-packs and winches. Except during initial placement, and movement to an alternative capping area, at least one of barges 12 and 14 is positioned and securely placed at all times. Alternatively, barges 12 and 14 can both be moved based upon elevation data or severe weather. When spreader barge 12 is moving, template barge 14 will have at least one spud 30 down which will hold barge 12 in place. Spreader barge 12 moves along the template barge 14 at a predetermined even rate until reaching its stopping point. At this time, spreader barge 12 is positioned and the template barge will step back. During these steps, distribution of the material is continuous, except when a complete change in the capping location occurs. Alternatively, spreader barge 12 is stationary for a predetermined time during which the capping material is distributed, after which it will be repositioned and re-commence distribution. The thickness of the capping layer can range from about 1½ inches to about 9 inches, the thickness being dependent upon the sediment being capped and the capping material. Alternatively, the capping layer thickness can be less than 1½ inches or greater than 9 inches.
Now referring to FIGS. 5 and 6 , the spreading means 24 has a distribution chute 66 connected to the reservoir 29 , a broadcast spinner 68 , and an actuator 70 . Capping material flows from the reservoir 29 and through the chute 66 . After traveling down the chute 66 the capping material reaches the spinner 68 and is thereby broadcast into the pool 28 . The spinner 68 is substantially disc-shaped and comprises an axis connector 72 and a plurality of distribution fins 74 . The axis connector 72 has an aperture extending through it, which is mounted to the chute 66 . The actuator 70 is a hydraulic system which causes the spinner 68 to spin. As capping material reaches the spinning spinner 68 , the fins 74 act on the material to centripetally distribute the capping material within pool 28 . The fins 74 extend radially outward from connector 72 and extend outward and substantially perpendicular to a spinner surface 76 . As shown in FIG. 6 , an exemplary spinner 68 includes six fins 72 . In an alternative embodiment, the spinner 68 has one or more fins 74 .
Alternatively, more than one spreading means 24 is connected to the reservoir 29 . By example, two distribution means 24 can simultaneously distribute capping material into pool 28 . The spinners 68 for the respective distribution means 24 are configured to spin in opposite directions, on spinning in a clockwise direction and the second spinning in a counter clockwise direction. Preferably the spinner 68 rotating in a clockwise direction is positioned to the right of the second spinner 68 , which provides for a greater distribution area within pool 28 . In at least one embodiment, the spreading means 24 includes a barge metering hopper and belt scale (not shown) for measuring the distributed capping material, and at least one spinner 68 to distribute the capping material into the pool 28 . It is further contemplated that the size and shape of the spinners are selected based upon the capping material and desired rate of distribution.
Upon entering receiving means 18 , the capping material passes through shaker 20 , which includes a vibrating dewatering screen. In one embodiment, shaker 20 is capable of de-watering the slurry in excess of 200 tons per hour, based upon a screen measuring about 6 feet wide by about 16 feet long. Once the slurried capping material is dewatered, the clean transport water will be discharged overboard within pool 28 . The capping material rolls off the end of the screen into distribution means 24 . One exemplary distribution means 24 is an Epoke Sirius® (Epoke Inc., Stittsville, Ontario, Calif.) 6.5 cubic yard spreader. Alternatively, the distribution system includes a conveyor with a belt scale and a J.F. Brennan Co. hardened metal spreader. Spreader 24 is located on the bow of the spreader barge, broadcasting the de-watered capping material in a uniform pattern. Individual capping material particles will hit the water and fall through the water column at a reduced velocity, relative to bucket dumping, thereby covering the soft sediment with minimal disturbance. Alternately, granular capping material transported by barge can be offloaded by bucket and fed into the barge metering hopper for delivery to spreader 24 .
In an alternative embodiment, spreader pool 28 is about 35 feet long by about 12 feet wide. Spreader pool 28 is an area of open water surrounded by barriers, that allow capping material to be placed into a confined area. The barriers are preferably wall-like structures that extend above the barge 12 surface in a range of about 2 feet to about 5 feet high. By example, the barriers can be constructed of plywood, cement, or durable fabric. By confining the distribution of capping material, turbidity issues are minimized, which in turn reduces agitation of the contaminated sediment. Spreader 24 broadcasts capping material into spreader pool 28 over a measured duration after which the spreader barge is winched back a specific distance alongside template barge 14 . By example, the distribution rate can range from about 40 to about 60 cubic yards per hour and include 6-foot spreader barge 12 steps. Alternatively, spreader barge 12 can move continuously. In yet another alternative embodiment, the distribution rate can range from about 60 to about 100 cubic yards per hour. In yet another alternative embodiment, the distribution rate is less than 40 cubic yards per hour.
Capping material volume is measured to ensure accurate placement. A primary volume measurement is determined by the spreading means 24 , which includes a belt scale that provides real time capping distribution weights. The size and speed of the conveyor can determine the amount of material sent to spreader 24 . Once the required volume of capping material is placed, a signal is sent from the spreader unit to an alarm which sounds, alerting the plant operators that it is time to slide the spreader barge back another 6 feet. This system provides a continuous real time measurement of the volume of material being placed. Capping material volume can be metered onshore by conveyor 36 before being fed into slurry pipeline 16 . Compared to spreader barge spreader 24 , conveyor 36 metering will be used to determine volume measurements over longer periods of time, such as per day or on a weekly basis.
Both pre- and post-placement bathymetric surveys can be performed at the placement areas. The bathymetric vessel is designed for operations in shallow water. The vessel can be equipped with a single frequency fathometer, two real-time kinematic (RTK) Global positioning units, and one laptop computer unit. Post placement bathymetric surveys can be conducted within twenty-four to forty-eight hours after the barge places material over an area for quality control and confirmation of proper capping material distribution.
Control center 26 includes a computer which can utilize a variety of sub-aquatic analysis and measuring software. By example, the control center includes Dredgepack® (Hypack, Inc., Middletown, Conn.) software and Wonderware® (Invensys Systems, Inc., Lake Forest, Calif.) software. Dredgepack® can be used for positioning the spreader barge 12 , while Wonderware® can track the production of capping material distribution data collected. Wonderware® can integrate the use of a plurality, four by example, of sounding sensors located in each corner of the spreader pool. The sensors provide RTK GPS for real time measurement of the materials elevation and the targeted elevation and location. Dredgepack® can provide illustrated pre-cover placement elevation in two profile views, along with a top view. As the material is added to the waterway floor, the sensors will measure and record the elevation of the placed material. The operator will visually see this elevation change in both profile views and the top view will display the change. In addition to tracking capping progress on a daily basis, each placement area can be divided into capping units. The capping units can be designated to assist the management of large sediment capping operations. Alternatively, the spreader 24 utilizes a Real Time Kinematic (RTK) Global Positioning System (GPS) for capping material position and elevation tracking. The RTK GPS system uses satellite links to two spreader barge mounted receivers, a fixed location receiver with known coordinates, and a geometric method, referred to as tri-lateration, to determine the real-time position and elevation of a point on the spreader 24 to within 4 centimeters. This reference point is configured at the capping material discharge location. As the spreader barge 12 travels, turns, and rises and falls on the lake, the system continually updates the northing and casting coordinates, heading, and elevation of the capping material discharge position. The coordinates of the spreader 24 are sent to a survey software system such as DredgePack. This software system can provide a continuous log of coordinates and elevations for the capping material discharge location and can provide tools to help the operator accurately locate the spreader barge 12 at required coordinates. For each sand spreading location, Intouch® software system inserts capping material spreading information into a Microsoft SQL Server database. The capping material spreading information stored in the database includes the time and date, position coordinates, actual sand tonnage spread, sand density, spreading time duration, etc. for that spreading step. All of this information is available to be viewed via an Internet web browser in the form of a pre-developed report.
Now referring to FIGS. 7A and 7B , an alternative embodiment of spreader 24 is shown. Two spinners 68 are suspended above pool 28 by a spreader frame 76 . Chute 66 provides capping material to the spinners 68 , which rotate and distribute the material within pool 28 in a semi-circular pattern 78 (See FIG. 7B ). Each spinner 68 has a substantially flat top surface 80 which receives the capping material immediately prior to the capping material being distributed through centripetal forces. Spinners 68 are tilted toward each other, such that surface 68 is not parallel with pool 28 . The orientation of spinners 68 can be altered to affect the distribution pattern 78 . Orientation of spinners 68 can range from a substantially flat orientation to greater than 20 degrees pitch in any direction.
An alternative embodiment of spinner 68 is shown in FIG. 8 . Spinner 68 includes three fins 74 , an axis connector 72 , and a substantially flat top surface 80 . Each fin 74 is attached to surface 80 through an L-bracket 82 . Any suitable connection means known in the art, such as welding, can be used to connect surface 80 to L-bracket 82 , and fins 74 to L-bracket 82 . Spinner 68 can be manufactured from a variety of durable materials known in the art, including low-cost metals and metal alloys. Alternatively, fins 74 can be manufactured from higher-cost materials having greater durability, such as composites, precious and semi-precious metals, and metal alloys. By example, surface 80 can be manufactured from 420 stainless steel, while the fins are manufactured from titanium alloys.
Although the invention has been described in considerable detail, within the preceding specification and figures, the detail is for the purpose of illustration only, and not to be limited to the embodiments and illustrations previously described. Those skilled in the art will recognize that many variations and modifications can be made to the invention without departing from the spirit and scope as described by the following claims. | Sub-aquatic sediment is covered with capping material by a capping system comprising a template barge and a spreader barge. While the spreader barge is distributing capping material, the template barge guides the spreader barge as it systematically moves over a pre-defined sediment capping region. The spreader barge comprises a spreader pool in which a broadcast spreader accurately and evenly distributes capping material within the pool, which then sinks to the sediment. The capping material is distributed with minimal disturbance to the sediment. | 4 |
CROSS REFERENCE
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 11/330,331 filed on Jan. 12, 2006, which is incorporated herewith by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to a light emitting device, and in particular to an enhanced brightness light emitting device comprising an encapsulation layer containing a very small amount of fluorescent material in it so as to solve the problems of color spots and halo phenomena occurred in the conventional light emitting diodes (LEDs).
[0004] 2. The Prior Arts
[0005] The fluorescent whitening agents can be applied in many fields, and mainly in cleaner (such as soaps and detergents), paper, textile, plastic, oil, painting, and the like. With the development of science and technology, the applied range of the fluorescent whitening agent has been increased. For example, the fluorescent whitening agent can be applied in the fluorescent probes, lasers, and especially in the LEDs. Recently, in the LED technology, most of the researches have been focused on the inorganic system. However, the inorganic compounds can cause the problems of heavy metal pollution. Furthermore, the light emitted by the conventional LEDs usually appears color spots (black or yellow spots) and halo phenomena due to its low brightness.
[0006] Thus, a need exists for an environmental-friendly light emitting device having high brightness and high luminous efficiency, and not showing color spots (such as black or yellow spots), and halo phenomena.
[0007] In U.S. Pat. No. 6,841,933, Yamanaka et al. disclosed that the organic fluorescent whitening agent (for example, 1,4-bis(2-methylstyryl)benzene (Bis-MSB) and trans-4,4′-diphenylstilbene (DPS)) can be used as phosphor for the white LEDs. However, the organic fluorescent whitening agent is usually degraded under UV irradiation. Therefore, when the conventional organic fluorescent whitening agents are used as the phosphor for LEDs, the brightness of LED always decreases over time. Furthermore, the organic fluorescent whitening agents are also easily degraded under high voltage and high temperature (>300° C.). Moreover, the conventional organic fluorescent whitening agents are not compatible with silicone resins which are widely used as an encapsulating material for LEDs and other semiconductors.
[0008] Moreover, because the blue LEDs can emit a light of wavelength of 450 nm or below (about 20% of light emitted by the blue LEDs), the eyes of users will be hurt. Furthermore, when the white LEDs are fabricated by combining the blue LEDs and YAG:Ce 3+ , the brightness can be enhanced significantly by such a combination only if the emitted light has a wavelength of between 420 to 470 nm. However, the brightness cannot be enhanced if the light source emits a wavelength of 410 nm or below. Moreover, when the encapsulation layer of the LED contains the conventional fluorescent material (such as 4,4′-bis(2-methoxystyryl)biphenyl) at a concentration ranging from 0.005 to 0.01 wt % based on the total weight of the encapsulation layer, the brightness of the LED actually decreases.
SUMMARY OF THE INVENTION
[0009] The objective of the present invention is to provide an enhanced brightness light emitting device with high brightness in order to overcome the problems set forth above.
[0010] To achieve the foregoing objective, the present invention provides an enhanced brightness light emitting device, comprising a light emitting element, and a transparent encapsulation layer which encloses the light emitting element. The transparent encapsulation layer includes a resin and a fluorescent material, and the fluorescent material is represented by the following general formula (I):
[0000]
[0000] wherein R is selected from one of the group consisting of phenyl substituted with alkoxy, substituted or unsubstituted anthracene group, substituted or unsubstituted pyrene group, and substituted or unsubstituted 9,10-anthraquinone group.
[0011] Also, the fluorescent material of the present invention can be selected from the group consisting of the following chemical structural formulae:
1. Non-Aromatic Fluorescent Materials:
[0012]
2. Aromatic Fluorescent Materials Containing Silicon:
[0013]
3. Non-Aromatic Fluorescent Materials Containing Silicon:
[0014]
[0015] The enhanced brightness light emitting device of the present invention can further comprise a photoluminescent phosphor (such as YAG:Ce 3+ ) disposed over the light emitting element, which can emit a second light upon excitation, wherein the first light emitted by the light emitting element can excite the photoluminescent phosphor, which subsequently emits a second light which has longer wavelength than the first light, and the second light and the first light unabsorbed by the photoluminescent phosphor are combined in the encapsulation layer including the resin and the fluorescent material, and then the fluorescent material is excited and emits a visible light with high brightness and high luminous efficiency outwards from the encapsulation layer.
[0016] It is worthy to be noticed that the fluorescent material represented by the above structural formulae can substantially completely absorb the light having a wavelength between 254 nm and 475 nm, and subsequently re-emit it with very high brightness, and thereby the problems of color spots (such as black or yellow spots) and halo phenomena occurred in the conventional LED can be eliminated. Moreover, the fluorescent materials used in the present invention are environmental-friendly materials, and they will not cause heavy metal pollution, and harmful metal radiation problems. Furthermore, the used amount of the fluorescent material of the present invention for achieving high brightness is extremely low.
[0017] On the other hand, the utensils coated with the fluorescent materials of the present invention can have anti-UV function, and moreover a light can easily penetrate through a board coated with the fluorescent materials of the present invention.
[0018] The foregoing and other objects, features, aspects and advantages of the present invention will become better understood from a careful reading of a detailed description provided herein below with appropriate reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a cross-sectional view of the enhanced brightness light emitting device according to one embodiment of the present invention;
[0020] FIG. 2 is brightness (LM)-time curves illustrating the variation in the brightness of the light emitting device corresponding to its encapsulation layer (in the case of silicone resin) containing, or not containing the fluorescent material (in the case of 4,4′-bis(2-methoxystyryl)biphenyl) measured at the height of 30 cm, and 50 cm every 24 hours, respectively; and
[0021] FIG. 3 is brightness increment (%)-time curves illustrating the increased brightness percentage of the light emitting device corresponding to its encapsulation layer (in the case of silicone resin) containing the fluorescent material (in the case of 4,4′-bis(2-methoxystyryl)biphenyl) relative to its encapsulation layer not containing the fluorescent material at the height of 30 cm, and 50 cm every 24 hours, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] The present provides an enhanced brightness light emitting device, comprising: a light emitting element being capable of emitting a first light; a photoluminescent phosphor disposed over the light emitting element, the photoluminescent phosphor emitting a second light at a wavelength longer than the first light when excited by the first light; and a transparent encapsulation layer enclosing the light emitting element and the photoluminescent phosphor, the transparent encapsulation layer including a resin and a fluorescent material, which emits a third light at a wavelength longer than the first light when excited by the first light, wherein the second light, the third light, and the first light unabsorbed are combined in the encapsulation layer, and after combination a visible light is emitted outwards from the encapsulation layer, and wherein the second light and the third light fall within substantially the same wavelength range from 520 nm and 550 nm.
[0023] The fluorescent material of the present invention can be a compound represented by the following general formula:
[0000]
[0000] wherein R is selected from one of the group consisting of phenyl substituted with alkoxy, substituted or unsubstituted anthracene group, substituted or unsubstituted pyrene group, and substituted or unsubstituted 9,10-anthraquinone group.
[0024] Specifically, the fluorescent material used in the present invention can be 4,4′-bis(2-methoxystyryl)biphenyl, 4,4′-bis{2-(9-anthracenyl)ethylenyl}biphenyl, 4,4′-bis{2-(1-pyrenyl)ethylenyl}biphenyl, or 4,4′-bis{2-(1-anthraquinonyl)ethylenyl}biphenyl. The above-mentioned four fluorescent materials are characterized in that they are symmetric biphenyl type compounds with two ethylenyl groups at 4,4′ positions, and the biphenyl type compounds with two ethylenyl groups at 4,4′ positions are bonded to the fluorescent functional groups through two ethylenyl groups. Examples of the fluorescent functional groups are methoxyphenyl group and its homologous; anthracene group and its homologous; pyrene group and its homologous; and 9,10-anthraquinone group and its homologous. The fluorescent materials having the above-mentioned characteristics can substantially completely absorb the light having wavelength between 254 nm and 475 nm, and subsequently re-emits it as a visible light with very high brightness. When 4,4′-bis(2-methoxystyryl)biphenyl is used as the fluorescent material, it can be excited by UV light and subsequently emits a blue light having a wavelength between 450 nm and 490 nm. When 4,4′-bis{2-(9-anthracenyl)ethylenyl}biphenyl is used as the fluorescent material, it can be excited by UV light and subsequently emits a yellowish-green light having a wavelength between 520 nm and 550 nm. When 4,4′-bis{2-(1-pyrenyl)ethylenyl}biphenyl is used as the fluorescent material, it can be excited by UV light and subsequently emits a blue light having a wavelength between 450 nm and 490 nm. When 4,4′bis{2-(1-anthraquinonyl)ethylenyl}biphenyl is used as the fluorescent material, it can be excited by UV light and subsequently emits a red light having a wavelength between 580 nm and 660 nm.
[0025] Also, the fluorescent material of the present invention can be a compound selected from the group consisting of the following chemical structural formulae:
1. Non-Aromatic Fluorescent Materials:
[0026]
2. Aromatic Fluorescent Materials Containing Silicon:
[0027]
3. Non-Aromatic Fluorescent Materials Containing Silicon:
[0028]
[0029] The fluorescent material of the present invention is present in an amount of from 0.001 to 0.1% by weights preferably from 0.005% to 0.01% by weight, based on the total weight of transparent encapsulation layer. The resin is present in an amount of from 99.9 to 99.999% by weight, preferably from 99.99 to 99.995% by weight, based on the total weight of transparent encapsulation layer.
[0030] The photoluminescent phosphor can be a blue phosphor that emits blue light at a wavelength from 450 nm to 490 nm when excited by the electromagnetic radiation of the light emitting element; a yellowish green phosphor that emits yellowish green light at a wavelength from 520 nm to 550 nm when excited by the electromagnetic radiation of the light emitting element; or a red phosphor that emits red light at a wavelength from 580 nm to 660 nm when excited by the electromagnetic radiation of the light emitting element.
[0031] In order to achieve the optimum brightness level, in the enhanced brightness light emitting device of the present invention, the blue phosphor is used with 4,4′-bis(2-methoxystyryl)biphenyl, or 4,4′-bis{2-(1-pyrenyl)ethylenyl}biphenyl to convert the emission of the light emitting element to the blue light; the yellowish green phosphor is used with 4,4′-bis{2-(9-anthracenyl)ethylenyl}biphenyl to convert the emission of the light emitting element to the yellowish green light; and the red phosphor is used with 4,4′-bis{2-(1-anthraquinonyl)ethylenyl}biphenyl to convert the emission of the light emitting element to the red light.
[0032] the resin of the transparent encapsulation layer can be silicone resin, or epoxy resin.
[0033] FIG. 1 is a cross-sectional view of the enhanced brightness light emitting device according to one embodiment of the present invention. In FIG. 1 , the light emitting element 20 of the enhanced brightness light emitting device 10 is GaN chip which can emit UV light or blue light outwards from the output surface 22 . The transparent encapsulation layer 30 is formed by mechanically mixing the silicone resin 40 with the fluorescent material of 4,4′-bis(2-methoxystyryl)biphenyl 50 in an organic solvent, applying the mixture around the light emitting element 20 , and drying it. The fluorescent material is present in an amount of from 0.1 to 1% by weight. The resin is present in an amount of from 99.9 to 99% by weight, based on the total weight of transparent encapsulation layer.
Brightness Test
[0034] The light emitting element 20 emits a blue light with a wavelength of 465 nm when subjected to a voltage of 3.6 V, and when the blue light with a wavelength of 465 nm passes through the transparent encapsulation layer 30 including the silicone resin 40 and the fluorescent material of 4,4′-bis(2-methoxystyryl)biphenyl 50 , the fluorescent material 50 converts the blue light at a wavelength of 465 nm into the blue light at a wavelength of 480 nm. The brightness (LM) of the blue light at a wavelength of 480 nm is measured at the height of 30 cm, and 50 cm every 24 hours, respectively, until the total measured time reaches a setting value of 1008 hours. The above test results are plotted in FIG. 2 .
[0035] In a similar way, in the case of without the fluorescent material of 4,4′-bis(2-methoxystyryl)biphenyl 50 in the transparent encapsulation layer 30 , the light emitting element 20 emits a blue light at a wavelength of 465 nm when subjected to a voltage of 3.6 V, and the blue light is then emitted outwards from the transparent encapsulation layer 30 . The brightness (LM) of the blue light is measured at the height of 30 cm, and 50 cm every 24 hours, respectively, until the total measured time reaches a setting value of 1008 hours. The above test results are also plotted in FIG. 2 .
[0036] The brightness increment percentage obtained from the data shown in FIG. 2 is plotted in FIG. 3 . The brightness increment percentage is calculated by dividing the brightness of the emitted blue light after passing through the transparent encapsulation layer 30 including both silicone resin 40 and the fluorescent material of 4,4′-bis(2-methoxystyryl)biphenyl 50 by the brightness of the emitted blue light after passing through the transparent encapsulation layer 30 only including silicone resin 40 at the height of 30 cm, and 50 cm, respectively (the total measured time is 1008 hours). The average brightness increment percentage at the height of 30 cm is 10.06%, and the average brightness increment percentage at the height of 50 cm is 9.74%. Therefore, if the transparent encapsulation layer of the light emitting device contains the fluorescent material of 4,4′-bis(2-methoxystyryl)biphenyl 50 , the brightness of the emitted light will be greatly enhanced, and thereby the problems of color spots (such as black or yellow spots) and halo phenomena occurred in the conventional LED can be eliminated.
Light-Emitting Efficiency Test
[0037] The light emitting element 20 is allowed to emit a first light having a wavelength of 365 nm, 375 nm, 395 nm, and 420 nm, respectively, as powered by the power supply, and then a second light with longer wavelength than the first light is emitted outwards from the transparent encapsulation layer 30 including silicone resin 40 and the fluorescent material of 4,4′-bis(2-methoxystyryl)biphenyl 50 as shown in FIG. 1 . The residual light intensity, consumption intensity, and the intensity of the excited light are measured and calculated. The consumption intensity is obtained by subtracting the residual light intensity from the exciting light intensity. The light-emitting efficiency is obtained by dividing the intensity of the excited light by the consumption intensity. These results are shown in Table 1.
[0000]
TABLE 1
Light-Emitting Efficiency
Transparent encapsulation layer including silicone
resin and 4,4′-bis(2-methoxystyryl)biphenyl
Exciting light
Light-
Wave-
Residual
Consumption
Intensity of
emitting
length
Intensity
intensity
intensity
excited light
efficiency
(nm)
(cd)
(cd)
(cd)
(cd)
(%)
365
9.622024
0.4514948
9.1705292
3.78128
41.23%
375
16.11016
0.7569989
15.3531611
4.759387
31.00%
395
28.78808
1.419859
27.368221
6.282627
22.96%
420
57.89266
2.580826
55.311834
7.07375
12.79%
[0038] As seen from Table 1, when the exciting light having a wavelength of 365 nm is used, the light-emitting efficiency is the best.
Required Concentration of the Fluorescent Material Test
[0039] The light emitting element 20 is allowed to emit a first light having a wavelength of 450 nm, and 550 nm, respectively, as powered by the power supply (20 mA current), and then a second light with longer wavelength than the first light is emitted outwards from the transparent encapsulation layer 30 consisting of the silicone resin 40 and the fluorescent material represented by the following chemical structural formula:
[0000]
[0040] The fluorescent material is present in an amount of 1 ppm, 2 ppm, 5 ppm, and 10 ppm, respectively, in the transparent encapsulation layer 30 . The brightness (LM) of the light emitting element 20 is measured. These results are shown in Table 2.
[0000]
TABLE 2
mcd
in the absence of
the fluorescent
nm
material
1 ppm
2 ppm
5 ppm
10 ppm
450 nm
5120
6100
6300
6000
5800
550 nm
7500
8600
9100
8800
8500
[0041] It can be seen from Table 2 that when the encapsulation layer contains the fluorescent material of the present invention at a concentration of 1 ppm, 2 ppm, 5 ppm, and 10 ppm, respectively, the brightness can be increased.
[0042] In the other case, the light emitting element 20 is allowed to emit a first light having a wavelength of 450 nm, and 550 nm, respectively, as powered by the power supply (20 mA current), and then a second light with longer wavelength than the first light is emitted outwards from the transparent encapsulation layer 30 consisting of the silicone resin 40 and the fluorescent material of 4,4′-bis(2-methoxystyryl)biphenyl 50 , and the fluorescent material is present in an amount of from 0.005% to 0.01% by weight based on the total weight of the encapsulation layer 30 , as shown in FIG. 1 . These results are shown in Table 3.
[0000]
TABLE 3
mcd
in the absence of the
nm
fluorescent material
0.005 wt %
0.01 wt %
450 nm
5120
4900
4850
550 nm
7500
7300
7100
[0043] It can be seen from Table 3 that when the encapsulation layer contains the conventional fluorescent material (such as 4,4′-bis(2-methoxystyryl)biphenyl) at a concentration ranging from 0.005 to 0.01 wt % based on the total weight of the encapsulation layer, the brightness actually is decreased.
[0044] Table 4 shows the wavelengths and the CIE chromaticity coordinates of the excited lights in this test.
[0000]
TABLE 4
Excited light
Exciting light
CIE chromaticity
Wavelength (nm)
Wavelength (nm)
coordinates
365
480
x = 0.1477, y = 0.2193
375
480
x = 0.1468, y = 0.2189
395
480
x = 0.1449, y = 0.2175
420
480
x = 0.1439, y = 0.2177
[0045] As seen from Table 4, the excited lights all fall in the range of the blue light spectrum.
[0000] Brightness vs. Concentration of the Fluorescent Material
[0046] The light emitting element 20 is allowed to emit a first light having a wavelength of 455 nm, 460 nm, 465 nm, and 470 nm, respectively, as powered by the power supply (20 mA current), and then a second light with longer wavelength than the first light is emitted outwards from the transparent encapsulation layer 30 consisting of the silicone resin 40 , and 8 to 15 wt % of YAG: Ce 3+ (designated by YAG in Table 5) together with 1 to 5 wt % of the fluorescent material represented by the following chemical structural formula (designated by ST in Table 5):
[0000]
[0047] The brightness and the CIE chromaticity coordinates are measured as shown in Table 5.
[0000]
TABLE 5
8 wt %
9 wt %
10 wt %
11 wt %
12 wt %
13 wt %
14 wt %
15 wt %
ST (1%) + YAG
X
0.255
0.253
0.254
0.255
0.254
0.26
0.265
0.279
Y
0.341
0.339
0.341
0.343
0.355
0.367
0.385
0.401
mcd (avg.)
9932
9812
9702
9573
9488
9312
9289
9210
ST (2%) + YAG
X
0.24
0.243
0.248
0.247
0.256
0.265
0.269
0.275
Y
0.311
0.317
0.33
0.334
0.344
0.358
0.361
0.373
mcd (avg.)
9769
9762
9529
9501
9410
9375
9333
9295
ST (3%) + YAG
X
0.254
0.256
0.255
0.258
0.261
0.276
0.278
0.28
Y
0.361
0.36
0.363
0.367
0.383
0.402
0.408
0.413
mcd (avg.)
9528
9476
9443
9378
9335
9289
9266
9176
ST (4%) + YAG
X
0.214
0.222
0.244
0.248
0.257
0.276
0.281
0.282
Y
0.305
0.322
0.337
0.352
0.355
0.367
0.377
0.394
mcd (avg.)
9276
9177
9126
9120
9004
8978
8871
8750
ST (5%) + YAG
X
0.23
0.241
0.255
0.27
0.286
0.288
0.295
0.296
Y
0.311
0.333
0.347
0.359
0.363
0.37
0.381
0.384
mcd (avg.)
9599
9419
9354
9131
8898
8811
8721
8686
[0048] As seen from Table 5, 1 wt % of the fluorescent material is preferably used.
[0000] Brightness vs. Fluorescent Material used at 460 nm
[0049] The light emitting element 20 is allowed to emit a first light having a wavelength of 460 nm, respectively, as powered by the power supply (20 mA current), and then a second light with longer wavelength than the first light is emitted outwards from the transparent encapsulation layer 30 including silicone resin 40 , and 8 to 15 wt % of YAG: Ce 3+ (designated by YAG in Table 6) 50 or 1 wt % of the fluorescent material represented by the following chemical structural formula (designated by ST in Table 6):
[0000]
[0050] The brightness and the CIE chromaticity coordinates are measured as shown in Table 6.
[0000]
TABLE 6
YAG
8 wt %
9 wt %
10 wt %
11 wt %
12 wt %
13 wt %
14 wt %
15 wt %
1 X
0.282
0.299
0.315
0.313
0.3
0.329
0.318
0.34
Y
0.389
0.421
0.45
0.44
0.422
0.472
0.459
0.489
mcd (avg.)
5470
6707
6531
6014
4924
4299
4702
5094
ST
1 wt %
X
0.19
Y
0.125
mcd (avg.)
5135
[0051] As seen from Table 6, the brightness of the light emitting device using 1 wt % of the fluorescent material of the present invention is comparable with the brightness of the light emitting device using 8 to 15 wt % of YAG at 460 nm.
[0052] The fluorescent materials of the present invention used in the transparent encapsulation layer of the light-emitting device have the advantages of (1) only 0.005 to 0.01 wt % of the fluorescent material is required to increase the brightness of the LEDs; (2) the LEDs with the fluorescent materials of the present invention can be operated under high voltage and high temperature (>300° C.) for a long time without deterioration of performance; (3) the fluorescent materials of the present invention is compatible with silicone resins which are widely used as an encapsulating material for LEDs; (4) when the blue LEDs are used with the fluorescent materials of the present invention, the wavelength of 450 nm or below emitted by the blue LEDs can be eliminated; (5) the LEDs with YAG and the fluorescent materials of the present invention can be operated under violet or UV light irradiation to enhance the brightness thereof, and however the LEDs with YAG can be only operated under blue light irradiation to enhance brightness thereof; and (6) the brightness of the light emitted by the light emitting element can be greatly enhanced through the fluorescent materials of the present invention so that the problems of color spots (such as black or yellow spots) and halo phenomena occurred in the conventional LEDs can be eliminated.
[0053] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention. Thus, it is intended that the present invention cover the modifications and the variations of this invention provided they come within the scope of the appended claims and their equivalents. | There is provided an enhanced brightness light emitting device, comprising a light emitting element, and a transparent encapsulation layer which encloses the light emitting element. The transparent encapsulation layer includes a resin and a fluorescent material selected from a non-aromatic fluorescent material, an aromatic fluorescent material, and a non-aromatic fluorescent material containing silicon. | 2 |
BACKGROUND
[0001] 1. Field
[0002] The present invention relates generally to monitor systems and more particularly to child monitor systems having a vibration element.
[0003] 2. Background
[0004] When parents have a young child they typically wish to monitor the child at all times. In fact, parents want to monitor their child even when they cannot occupy the same room as the child. Child monitors, also known as nursery monitors or baby monitors, make this possible.
[0005] Traditional child monitors allow parents to monitor the activities of a child located in another part of a house by transmitting sounds associated with the child to the parents. These sounds could include the child's breathing or general sounds associated with play. The child monitors typically consist of two units, one acting as a transmitter and the other a receiver. In operation, the parents place the transmitter in relative proximity to the child and keep the receiver in close proximity to themselves. The transmitter unit receives sounds associated with the child and transmits these sounds to the receiving unit, which outputs these sounds to the parent. These sounds allow the parent to monitor the child and the parents act accordingly should the child need attention.
[0006] These traditional child monitors have a drawback, however, in that that the feature that makes them most useful has a limitation. Traditional child monitors allow parents to monitor their child by transmitting sounds associated with the child. However, outputting the sounds produced by the child can be inappropriate in certain circumstances or at times the sounds are simply inaudible and therefore ineffective. For example, outputting these sounds may be inappropriate or ineffective when the parent talks on the telephone or when a visitor is present. The parent, however, will decrease the usefulness of the device should he or she significantly decrease the volume of the monitor to remedy this problem. Alternatively, engaging in an activity that itself generates a significant amount of noise such as vacuuming or operating a dishwasher or washer/dryer, for example, makes sounds transmitted by a child monitor inaudible, also rendering it ineffective.
[0007] Consequently, a need exists for an improved child monitor system which allows parents to monitor their child using audible signals as well as alternative stimulation to alert parents that their child may need attention.
SUMMARY
[0008] Embodiments disclosed herein address the above stated need by providing a system and method for monitoring a child in a remote location by providing a monitoring system comprising two units, one of which transmits audio signals from the child's location and the other of which receives the transmitted signals at the parent's location and which vibrates when the audio signals reach a threshold level.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is a schematic view of a first embodiment of a monitor system of the present invention.
[0010] [0010]FIG. 2 depicts an operating mode of the monitor system of FIG. 1.
[0011] [0011]FIG. 3 is a schematic view of another example embodiment of the monitor system of FIG. 1.
[0012] [0012]FIG. 4 is a schematic view yet another example embodiment of the monitor system of FIG. 1.
[0013] [0013]FIG. 5 is a flowchart illustrating a method for monitoring a child in a remote location according to an example embodiment of the present invention.
[0014] [0014]FIG. 6 is a perspective view of an example embodiment of the monitor system of the present invention.
[0015] [0015]FIGS. 7 and 8 are frontal and side views of the local unit of the monitor system of FIG. 6.
[0016] [0016]FIGS. 9 and 10 are frontal and side views of the remote unit of the monitor system of FIG. 6.
DETAILED DESCRIPTION
[0017] Overview
[0018] The present invention relates generally to child monitoring systems. According to various example embodiments of the present invention, a monitoring system is disclosed which transmits audible signals and includes a vibration element sensitive to audible signal levels.
[0019] [0019]FIG. 1 schematically illustrates a monitoring system 100 according to an example embodiment of the present invention. Monitoring system 100 includes a local unit 102 and a remote unit 104 . Local unit 102 includes a receiver 110 , an audio output transducer 114 , and a vibration element 112 . Remote unit 104 includes a transmitter 108 and an audio input transducer 106 .
[0020] Transmitter 108 and receiver 110 represent any transceiver hardware, software, or combination of hardware or software that transmit signals from one device to another either wirelessly or via a wired connection. Audio output transducer 114 and audio input transducer 106 represent any devices including speakers and microphones for outputting and receiving audio signals. Vibration element 112 represents any device which produces vibratory motion.
[0021] The operation of monitor system 100 is shown in FIG. 2. Audio input transducer 106 of remote unit 104 receives an audio input signal 202 . Audio input transducer 106 converts audio input signal 202 into an audio signal 204 . Transmitter 108 then transmits audio signal 204 to receiver 110 of local unit 102 . Audio output transducer then converts audio signal 204 into an audio output signal 206 . Should audio signal 204 exceed a threshold signal value vibration element 112 will activate, which causes local unit 102 to vibrate. Consequently, monitor system 100 provides both an audio output and a vibratory response to the user.
[0022] [0022]FIG. 3 schematically illustrates another example embodiment of monitor system 100 of the present invention. In this embodiment, monitor system 100 includes a vibration termination switch 302 and a mode selector 304 . Vibration termination switch 302 and mode selector 304 represent any hardware, software, or combination of hardware and software which act as a switch.
[0023] In this configuration, the operation of monitor system 100 is similar to that described in connection with FIG. 2, however vibration termination switch 302 and mode selector 304 provide additional functionality. Specifically, should vibration element 112 be activated, the user may choose to stop the operation of this element by using vibration termination switch 302 . In addition, this configuration allows the user to select between multiple operating modes. The user may choose to operate monitor system 100 in “audio only” mode by disabling the vibration element altogether, in which case, the user may use mode selector 304 to have monitor system 100 output only audio signals with no vibration. Alternatively, again by using mode selector 304 , the user may choose to operate monitor system 100 in sound and vibration mode to both output audio signals and vibrate should the audio signals reach a certain level. Alternatively, the user may choose to operate monitor system 100 in vibration only mode in which case monitor system 100 will not output audio signals but will vibrate should those signals reach a threshold level.
[0024] In addition to the various additional features made possible by the example embodiment of the present invention described above, FIG. 4 depicts yet another example embodiment of the present invention. This example embodiment of monitor system 100 includes a threshold level selector 402 and a display 404 . Threshold level selector 402 represents any hardware, software, or combination of hardware and software which acts as a signal-level selection device. Display 404 represents any suitable display hardware, including any combination or configuration of LEDs or other light emitting sources.
[0025] The operation of the monitor system 100 shown in FIG. 4 is similar to that described in connection with FIGS. 2 and 3 but with additional functionality. Specifically, threshold level selector 402 allows the user to select the level of the audio signal at which vibration element 112 will operate. Also, display 404 , in an example embodiment, consists of several LEDs, which activate at successively higher levels of the audio signal. For example, display 404 consists of 6 LEDs, the first LED is activated when the audio signal is at its lowest level and all 6 are activated when the signal is at its highest level. In one embodiment of the present invention, using threshold level selector 402 , the user may set monitor system 100 to vibrate when the third LED is activated, for example.
[0026] The artisan will recognize that the additional elements described in FIGS. 3 and 4 may be implemented in any combination without departing from the spirit and scope of the present invention. Further, the monitoring system may be used to monitor children, but may also be used in any situations in which sound is generated. For example, the monitoring system could be used to monitor the ill and elderly, pets, or cars entering or exiting a driveway, for example. Monitor system 100 may also transmit video signals as well as audio signals without departing from the spirit and scope of the present invention.
[0027] [0027]FIG. 5 is a flowchart 500 that describes the operation of an example embodiment of the present invention. In operation 502 , remote unit 104 is in a location remote from local unit 102 . FIGS. 1, 2, and 3 depict remote unit 104 and local unit 102 and their respective components in various configurations.
[0028] In operation 504 , acoustic sound is received at remote unit 104 . As shown in FIG. 2, audio input transducer 106 of remote unit 104 receives audio input signal 202 .
[0029] In operation 506 , a signal representing the acoustic sound is transmitted from remote unit 104 to local unit 102 . As shown in FIG. 2, audio input transducer 106 of remote unit 104 receives audio input signal 202 and converts it to input signal 204 which transmitter 108 transmits to receiver 110 of local unit 102 .
[0030] In operation 508 , vibration element 112 is activated when input signal 204 is above a threshold level. As shown in FIG. 2, vibration element 112 will activate should input signal 204 exceed a threshold level causing local unit 102 to vibrate.
[0031] In operation 510 , the vibration element is terminated after it has been activated. As shown in FIGS. 3 and 4, after vibration element 112 has been activated, the user may terminate its operation using vibration termination switch 302 .
[0032] [0032]FIG. 6 depicts an exemplary implementation of the monitor system 100 , illustrated schematically above, of the present invention. This example embodiment includes local unit 102 , and remote unit 104 . Local unit 102 includes an audio output transducer 144 , which is implemented as a speaker (1″/5 cm) located behind the perforated front face of the housing of local unit 104 , and, as shown in FIG. 7, several visual displays and user controls. The displays include a POWER ON/LOW BATTERY LED 708 , and a sound level indicator or display 706 implemented as a series of LEDs. The user controls include an ON/OFF VOLUME switch 702 , an A/B channel select switch 704 , mode selector 304 and vibration termination switch 302 . Local unit 102 also includes a clip 802 , as shown in FIG. 8, such that local unit 102 may be worn on the person of the user.
[0033] Local unit 102 also includes a vibration element that, when activated, causes local unit 102 to vibrate. The vibration element includes a small motor driving a shaft with an eccentrically mounted weight.
[0034] Power to the electronic components of local unit 102 is supplied by a main power supply which, in this example embodiment, consists of three rechargeable AAA batteries housed in a battery compartment located in the rear housing of local unit 102 , but may be any other suitable AC or DC power supply.
[0035] Remote unit 104 includes audio input transducer 106 , which is implemented as a condenser microphone mounted on the front face of the housing of remote unit 104 , AC power adapter 602 , and as shown in FIGS. 9 and 10, a POWER ON LED 900 , A/B channel select 1002 , and ON/OFF switch 1004 .
[0036] Power to the electronic components of remote unit 104 is provided by AC power adapter 602 , however internal DC power (such as batteries) could also be used.
[0037] The transmitter and receiver circuitry used in the local and remote units may be any standard circuitry as could be readily selected by the artisan. One suitable implementation is a 49 MHz system available from Excel Engineering, Ltd. of Japan. Many other systems (including for example, 900 MHz systems) are available from various suppliers.
[0038] In operation, to monitor a child for example, the user places remote unit 104 in relative proximity to the child and the user either places local unit 102 in the room with the user or wears local unit 102 on his or her person using clip 802 . Audio input transducer 106 of remote unit 104 receives audible inputs associated with the child and transmits them to local unit 102 . Local unit 102 will then output these sounds via audio output transducer 114 such that the user may be aware of the audible activities of the child. LED display 706 includes six LEDs, which illuminate in succession depending on the audio signal level. In this example embodiment, the single LED to the lower left of LED display 706 illuminates when the audio signal is at its lowest level, and all six illuminate when the audio signal is at its greatest level. In addition, should the sounds exceed a threshold level, local unit 102 will vibrate thus providing an alternate way of alerting the user to activities of the child. In an example embodiment, when the audio signal level is such that LEDs one through three are illuminated and remain so for three seconds, local unit 102 will vibrate. This example embodiment allows the user a choice of receiving both audio output and vibration or, alternatively, vibration only by using volume control 702 to decrease the volume completely, thus muting the audio output.
[0039] Once local unit 102 begins to vibrate, the user may choose to terminate the vibration by depressing vibration termination switch 302 , which, when done, disables the vibration element for one minute in this example embodiment. Also, the user may use mode selector 304 to eliminate the vibration option altogether. By doing this, the unit will then operate as a traditional child monitor by only providing audio output (in addition to the visual LED display in this example embodiment).
[0040] In an alternative implementation, the function of mode selector 304 and vibration termination switch 302 can be combined. Thus, a single switch could be used to enable or disable the vibration function (and if enabled, the user could terminate vibration once started by changing the switch to the disable position.
[0041] The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. | The present invention discloses a system and method for monitoring a child in a remote location by providing a monitoring system comprising two units which transmit audio signals from the child's location to the parent's location and the system vibrates when the audio signals reach a threshold level. | 6 |
RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No. 13/030,783 which was filed on Feb. 18, 2011, which is a continuation of co-pending application Ser. No. 10/020,484 which was filed on Dec. 21, 2001, which are hereby incorporated by reference herein in its entirety.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] [Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[0003] [Not Applicable]
BACKGROUND OF THE INVENTION
[0004] This invention relates to a gaming machine. More particularly, the invention relates to a bill acceptor for a gaming machine and to a method of operating a bill acceptor of a gaming machine.
[0005] It is becoming more and more prevalent for gaming machines to accept “paper” money or bank notes from players wishing to play gaming machines. As a result, more and more gaming machines include bill acceptors for such bank notes.
[0006] It is important that a bill acceptor be extremely accurately set to ensure that the insertion of false or counterfeit bank notes is kept to a minimum thereby minimising losses which the gaming machine operator may suffer.
[0007] Because the bill acceptor is a sensitive item, it may have a tendency to have a high rejection rate. As a result, a gaming machine equipped with such a bill acceptor may not be frequented by players wishing to use bank notes due to the rejection of the bank notes by the bill acceptor.
[0008] It is also desirable that, should one wish to alert a technician to the fact that a bill acceptor may be malfunctioning, it be done in a discrete manner so as not to disturb a player playing that gaming machine who may have been using another form of credit such as coins, tokens, cards, or the like.
BRIEF SUMMARY OF THE INVENTION
[0009] According to a first aspect of the invention, there is provided a bill acceptor for a gaming machine, the bill acceptor comprising:
[0010] a receiving zone for receiving a bill;
[0011] a sensing device at an input region of the receiving zone for sensing at least one characteristic of the bill;
[0012] a controller in communication with the sensing device for receiving an output signal from the sensing device; and
[0013] an annunciator controlled by the controller to be activated when a bill acceptance rate of the controller drops below a predetermined threshold.
[0014] The term “bill” is to be understood in this specification, unless the context clearly indicates otherwise, as a form of paper currency such as a bank note. Further, the term “bill acceptance rate” as it is used in this, specification is to be understood, unless the context clearly indicates otherwise, as the number of bills which are accepted in a batch of bills tendered to the gaming machine. It does not refer to the speed with which the controller accepts or rejects a tendered bill.
[0015] The receiving zone may incorporate a platen on which the bill is received and a slot at an end of the platen into which the bill is to be inserted. The platen may be arranged in a midtrim of the machine.
[0016] The sensing device may be arranged within the machine, inwardly of the slot. The sensing device may sense at least one of optical, magnetic and dimensional characteristics of the bill. In use, more than one of these characteristics may be sensed by the sensing device to reduce the prevalence of fraudulent or counterfeit bills.
[0017] The receiving zone may include an attracting means for indicating to a patron where the bill is to be inserted into the slot. The attracting means may comprise an array of illuminating elements arranged in the platen of the receiving zone.
[0018] In addition, the annunciator may also be arranged in the receiving zone.
[0019] The controller may cause the array of illuminating elements to be illuminated in a predetermined, first pattern and the annunciator may be implemented in the form of an illumination of the illuminating elements in a second, different pattern. The illuminating elements may be, for example, light emitting diodes (LED's). The LED's may be arranged in two rows. The rows may converge towards the slot. The first pattern may comprise sequential energising of corresponding LED's in each row followed by sequential de-energising of the corresponding LED's in each row. This may then constitute the first pattern. Upon completion of the first pattern, all the LED's may be energised so that they are all simultaneously illuminated and this may constitute the second pattern being the implementation of the annunciator.
[0020] Accordingly, the second pattern may be activated after completion of the first pattern when the bill acceptance rate has dropped below said predetermined threshold. This predetermined threshold may be set as desired by an operator of the gaming machine. For example, the threshold may be a bill acceptance rate of about 70% to 90% of tendered bills, preferably about 75% to 85% of tendered bills and, optimally, about 80% of tendered bills.
[0021] The gaming machine may be connected to a network. When the controller of such a gaming machine is connected to the network, a network monitoring system may monitor the acceptance rate of bills by the controller and may activate an alarm means when the acceptance rate drops below the predetermined threshold. This gives venue operating and service personnel an on-line and immediate indicator of the performance of the bill acceptor of the gaming machine. The monitoring system may activate a visual or audible alarm indicating the need for attention to the bill acceptor.
[0022] According to a second aspect of the invention, there is provided a method of operating a bill acceptor of a gaming machine, the method including the steps of:
[0023] sensing at least one characteristic of a bill inserted into the bill acceptor;
[0024] monitoring a bill acceptance rate by a controller; and
[0025] activating an annunciator when the bill acceptance rate drops below a predetermined threshold.
[0026] The method may include energising illuminating elements of the bill acceptor in a predetermined pattern and, when the bill acceptance rate drops below said threshold, energising the illuminating elements in a second, different pattern, said second pattern of illumination of the illuminating elements serving as the annunciator. The second pattern of illumination of the illuminating elements may follow completion of the first pattern.
[0027] As indicated above, when the gaming machine is connected to a network, the method may include transmitting a signal on the network to which the gaming machine is connected to a network monitoring system to activate an alarm means when the bill acceptance rate drops below said predetermined threshold.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0028] The invention is now described by way of example with reference to the accompanying drawings in which:
[0029] FIG. 1 shows a perspective view of a gaming machine;
[0030] FIG. 2 shows a block diagram of a control circuit of the gaming machine;
[0031] FIG. 3 shows a block diagram of a controller of a bill acceptor of the gaming machine;
[0032] FIG. 4 shows a sequence of illumination of illuminating elements of the bill acceptor of the gaming machine; and
[0033] FIG. 5 shows operation of an annunciator of the bill acceptor of the gaming machine.
DETAILED DESCRIPTION OF THE INVENTION
[0034] In FIG. 1 , reference numeral 10 generally designates a gaming machine, including a game, in accordance with the invention. The machine 10 includes a console 12 having a video display unit 14 on which a game 16 is played, in use. The game 16 is a spinning reel game which simulates the rotation of a number of spinning reels 18 . A midtrim 20 of the machine 10 houses a bank 22 of buttons for enabling a player to play the game 16 . The midtrim 20 also houses a credit input mechanism 24 including a coin input chute 24 . 1 and a bill collector 24 . 2 . The mechanism 24 may, in addition to the coin input chute 24 . 1 and the bill collector 24 . 2 , include a credit card reader (not shown) or any other type of validation device.
[0035] The machine 10 includes a top box 26 on which artwork 28 is carried. The artwork 28 includes paytables, details of bonus awards, etc.
[0036] A coin tray 30 is mounted beneath the console 12 for cash payouts from the machine 10 .
[0037] Referring to FIG. 2 of the drawings, a control means or control circuit 32 is illustrated. A program which implements the game and user interface is run on a processor 34 of the control circuit 32 . The processor 34 forms part of a controller 36 which drives the screen of the video display unit 14 and which receives input signals from sensors 38 . The sensors 38 include sensors associated with the bank 22 of buttons and touch sensors mounted in the screen. The controller 36 also receives input pulses from the mechanism 24 indicating that a player has provided sufficient credit to commence playing.
[0038] Finally, the controller 36 drives a payout mechanism 40 which, for example, may be a coin hopper for feeding coins to the coin tray 30 to make a pay out to a player when the player wishes to redeem his or her credit.
[0039] The bill acceptor 24 . 2 includes a platen 42 leading to an input slot 44 . An illuminating means in the form of an array of light emitting diodes (LED's) 46 is arranged in the platen 42 of the bill acceptor 24 . 2 .
[0040] The bill acceptor 24 . 2 further includes a sensing device in the form of a sensor array 48 ( FIG. 3 ). The sensor array 48 senses optical, magnetic and dimensional characteristics or properties of a bill tendered to the bill acceptor 24 . 2 of the gaming machine 10 . The sensor array 48 outputs signals on line 50 to a controller 52 . The controller 52 is a bill acceptor controller and communicates with the controller 34 of the gaming machine 10 .
[0041] The controller 52 includes a group of counters 54 . A first counter of the group of counters 54 is incremented each time a bill is accepted by the bill acceptor 24 . 2 .
[0042] Accordingly, when a bill is tendered to the bill acceptor 24 . 2 by being placed on the platen 42 it is received in the slot 44 and is drawn into the sensor array 48 by a transport motor 56 under the action of the controller 52 . The bill is then sensed by the sensor array 48 which determines whether or not its optical, magnetic and dimensional properties meet the required criteria. If the bill is accepted, the transport motor 56 is again energised which feeds the bill to a receptacle (not shown) contained within the console 12 of the gaming machine 10 . The first counter of the group of counters 54 is incremented by one.
[0043] Conversely, if the sensor array 48 determines that the bill is unacceptable, the transport motor 56 is operated in the reverse direction and the note is ejected from the slot 44 of the bill acceptor 24 . 2 . A second counter of the group of counters 54 is incremented by one.
[0044] After each tender of a bill, the controller 52 updates its calculation of the bill acceptance rate (BAR) according to the formula:
[0000] BAR(%)[A/(A+R)].times.100%,
[0000] where A=value of first counter of the group of counters 54 ; and R=value of second counter of the group of counters 54 .
[0045] When the acceptance rate as determined by the controller 52 is at or above the predetermined threshold, for example, a BAR of 80%, the array of LED's 46 of the bill acceptor 24 . 2 is energised in a predetermined, first pattern under the action of the controller controlling a lighting system 58 .
[0046] A typical pattern is as shown in FIG. 4 of the drawings and is designated generally by the reference numeral 60 . The array 46 comprises eight LED's 62 arranged in two converging rows 64 . The rows 64 converge towards the slot 44 of the bill acceptor 24 . 2 .
[0047] Under the control of the lighting system 58 , in State 0 , all of the LED's 62 remain de-energised. Thereafter, in a first state, the first LED 62 in each row is energised. By “first” is meant those LED's furthest from the slot 44 . In the second state, the first LED's 62 remain energised and the second LED's 62 are also energised. Similarly, in the third and fourth states the third LED 62 in each row 64 and fourth LED 62 in each row 64 are energised, respectively. In State 5 , the first LED's 62 are de-energised while the remaining LED's 62 in each row remain energised. In the sixth state, the second LED 62 in each row 64 is de-energised and in the seventh state the third LED 62 in each row is de-energised.
[0048] It will be appreciated that this happens reasonably quickly to create the impression of the LED's 62 being illuminated towards the slot 44 to create the impression of something being fed towards the slot 44 to act as an attracting means to a patron wishing to insert a bill into the bill acceptor 24 . 2 .
[0049] When the BAR is above the predetermined threshold, the pattern 64 continues indefinitely.
[0050] However, when the BAR drops below the predetermined threshold, upon completion of the pattern 60 , a new pattern (as shown by reference numeral 66 in FIG. 5 of the drawings) is interposed between States 7 and 0 . In other words, once the last LED 62 in each row 64 of the array 46 has been energised as in the case of State 7 , all the LED's 62 in each row 64 are energised before they are all de-energised as is shown for State 0 . This new pattern 66 continues to be inter posed between State 7 and State 0 for as long as the BAR remains below the predetermined threshold.
[0051] With this arrangement, a technician can, by monitoring the pattern 60 , determine whether or not the BAR of the controller 52 is above the required threshold and, if not, is alerted by the annunciator as implemented by the pattern 66 to take the appropriate remedial action.
[0052] It is an advantage of the invention that the pattern 66 , which functions as the annunciator for the technician, is discrete and that a player playing the gaming machine 10 using other means of credit input, such as coins or a card, is not disturbed by the change in pattern on the bill acceptor 24 . 2 .
[0053] The gaming machine 10 may be connected to a network in the venue. In that case, the controller 52 feeds information regarding the BAR to a venue network system 68 ( FIG. 3 ) via a network communications line 70 . The system 68 then gives venue operating and service personnel an on-line and immediate indicator of the performance of the bill acceptor 24 . 2 of each gaming machine 10 enabling remedial action to be taken in an expedited manner when the BAR of any gaming machine in the network drops below the predetermined threshold. The system 68 could, for example, activate a visual or audible alarm (not shown) indicating the need for attention to a bill acceptor 24 . 2 of any gaming machine on the network.
[0054] It is an advantage of the invention that a discrete arrangement is provided for determining the bill acceptance rate of a bill acceptor 24 . 2 of a gaming machine 10 , whether networked or not. It will be appreciated that if the controller 52 has a too high rejection rate of bills, the revenue received by the venue in which the gaming machine 10 is installed could be adversely affected as players may not have coins to play the machine instead. Accordingly, it is important that, when a bill acceptor 24 . 2 of a gaming machine 10 has an unacceptable high rejection rate, remedial action can be taken urgently.
[0055] In addition, the manner in which a technician is alerted to a malfunctioning bill acceptor 24 . 2 takes place in a discrete manner using the invention so that patrons are not disturbed in their playing of the gaming machine. | A bill acceptor 24.2 for a gaming machine includes a receiving zone for receiving a tendered bill. A sensing device 48 is arranged at an input region of the receiving zone for sensing at least one characteristic of the bill A controller 52 is in communication with the sensing device 48 for receiving an output signal from the sensing device 48 . An annunciator 58 is controlled by the controller 52 to be activated when a bill acceptance rate of the controller 52 drops below a predetermined threshold. | 6 |
BACKGROUND OF THE INVENTION
Cephalosporins like Cefaclor, Cefroxadine, Ceftizoxime, Ceftibuten, etc., are clinically useful antibiotics. The manufacturing process for these drugs involves multiple steps and hazardous chemicals, and poses many environmental problems. One of the key intermediates used in the manufacture of these cephalosporin antibiotics is 7-acylamino-3-hydroxy-cephem-1-oxide-4-carboxylic acid esters.
The synthesis of 7-acylamino-3-hydroxy-cephem-4-carboxylate-1-oxide was reported earlier by Scartazzini et al. in U.S. Pat. Nos. 4,389,524 (June 1983); 4,447,658 (October 1984), 4,591,642 (May 1986); and 4,668,781 (May 1987), and by Kukolja et al. in U.S. Pat. Nos. 3,917,587 (November 1975) and 4,031,084 (June 1977) through the ozonolysis of 7-acylamino-3-exomethylene-cepham-4-carboxylate and corresponding 1-oxides. Scartazzini et al. have greatly emphasized the formation of a keto-compound (shown as IV below) due to keto-enol tautomerism of the 3-hydroxy cephem compound and most of the examples in the patents by Scartazzini et al. are limited to benzhydryl esters only. The application of 3-hydroxy cephem benzhydryl ester is limited. Further, the formation and characterization of Z- and E-rotamers of 3-hydroxy cephem derivatives have never been visualized or experienced earlier.
SUMMARY OF THE INVENTION
In accordance with the present invention, the previously unknown Z- and E-rotamers of 3-hydroxy cephem derivatives have been produced, isolated, and characterized. The Z- and E-rotamers of 4-hydroxy cepham derivatives may be visualized as follows: ##STR1##
In the present invention, the 3-hydroxy cephem derivative which has a non-hydrogen bonded 3-hydroxy group has been assigned Z-rotamer configuration, whereas the 3-hydroxy cephem derivative which has a hydrogen bond between the 3-hydroxy group and the carbonyl of the 4-ester group has been assigned E-rotamer configuration.
Z- and E-rotamers differ significantly in chemical and physical properties. E-rotamer is thermodynamically more stable. In view of the greater thermodynamic stability and higher solubility of E-rotamer in organic solvents, it offers several advantages over the Z-rotamer when produced and used in subsequent synthetic steps on commercial scale.
The present invention also relates to a novel process for the manufacture of Z- and E-rotamers of 7-acylamino-3-hydroxycephem-4-carboxylate-1-oxide (II and III) from 7-acylamino-3-exomethylenecepham-4-carboxylate-1-oxide (I). The process of this invention is practiced by treating 3-exomethylene cepham derivatives with ozone. Z-rotamer is isolated by filtering the solid after ozonolysis in an inert organic solvent in the presence of an organic acid and subsequent decomposition of the ozonide. E-rotamer is obtained exclusively by the addition of some inorganic or organic base during ozonolysis in an inert organic solvent and removal of the solvent at low temperature. Z-rotamer when dissolved in an organic solvent or heated in an organic solvent or treated with a base gives E-rotamer. The formation of Z- or E-rotamers depends on the pH of the reaction medium, the polarity of the organic solvents used in ozonolysis, and the size of the protecting group used in esterification at position-4. Due to strong hydrogen bonding between the 3-hydroxy group and the carbonyl group of the 4-ester group, E-rotamer would never exhibit keto-enol tautomerism.
The manufacturing process for the Z- and E-rotamers (II and III) is outlined below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the IR spectrum of the Z-rotamer of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxy-cephem-4-carboxylate-1-oxide.
FIG. 2 shows the IR spectrum of the E-rotamer of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxy-cephem-4-carboxylate-1-oxide.
FIG. 3 shows the mass spectrum of the Z-rotamer of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxy-cephem-4-carboxylate-1-oxide.
FIG. 4 shows the mass spectrum of the E-rotamer of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxy-cephem-4-carboxylate-1-oxide.
DETAILED DESCRIPTION
According to the present invention, 3-exomethylene cepham-4-carboxylate-1-oxide (I) is subjected to ozonolysis under varying pH conditions and inert organic solvents of varying polarity as follows: (a) ozonolysis in an inert organic solvent in the presence of a base at a temperature of about -80° C. to 20° C. provides E-rotamer (III) of 3-hydroxy-cephem derivative, (b) ozonolysis in an inert organic solvent in the presence of acetic acid at -80° C. to +20° C. provides Z-rotamer (II) of 3-hydroxy cephem derivative, and (c) ozonolysis in an inert organic solvent at -80° C. to +20° C. without acid or base gives a mixture of Z- and E-rotamers of 3-hydroxy cephem derivatives. Z-rotamer being insoluble in most of the organic solvents is filtered out and E-rotamer is recovered from the mother liquor after concentration at a lower temperature.
Z-rotamer of 3-hydroxy cephem derivative (II) on heating or dissolving in an organic solvent or treatment with an organic base or inorganic base gives E-rotamer (III) which is thermodynamically more stable. All attempts to convert E-rotamer to Z-rotamer have failed.
In the formulae (II) and (III), R is an amino protecting group such as aryl, aralkyl, or aryloxyalkyl, such as phenoxy lower alkyl, phenyl lower alkyl, thienyl lower alkyl, etc., and R 1 is linear or branched chain alkyl, aryl, aralkyl, aryloxyalkyl, or aroxyalkyl, such as benzyl, p-methoxybenzyl, p-nitrobenzyl, diphenylmethyl, etc.
Solvents which can be employed in the present process are those solvents which are inert to oxidation by ozone. Suitable solvents in the present process include, for example, methylene chloride, chloroform, ethylene chloride, 1,1,2-trichloroethane, acetonitrile, propionitrile, methyl acetate and ethyl acetate. The most preferred solvent in the process is methylene chloride for E-rotamer and ethyl acetate for Z-rotamer.
The temperature range which can be used in the process of this invention is about -80° C. to about +20° C. The preferred temperature is between -40° C. to +10° C.
The organic bases which can be used in the above process for the production of E-rotamer (III) are, for example, pyridine, triethylamine, dimethylaniline, quinoline, etc., whereas inorganic bases which could be employed are, for example, sodium bicarbonate, potassium bicarbonate, potassium carbonate, sodium carbonate, etc.
Z-rotamer (II) and E-rotamer (III) differ in chemical/physical properties such as melting point, solubility, chemical reactivity, IR and mass spectra. As shown in FIG. 1, in the IR spectrum of Z-rotamer of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxycephem-4-carboxylate-1-oxide, a sharp signal of the 3-hydroxy group appears at about 3300 cm -1 , and a signal for 3-keto appears at 1755 cm -1 . In the IR spectrum of the corresponding E-rotamer (FIG. 2), the 3-hydroxy signal is very weak and the 3-keto signal is not present due to the hydrogen bonding with the carbonyl of the 4-ester group. Also, in the case of Z-rotamer, the carbonyl of the 4-ester group appears at 1717 cm -1 . In E-rotamer, the carbonyl of the 4-ester group is shifted towards lower wave number and appears at about 1690 cm -1 due to hydrogen bonding between the carbonyl of the 4-ester group and the 3-hydroxy group. In mass spectra of both rotamers (see FIGS. 3 and 4), there is a marked difference in the intensities of the peaks.
Z-rotamer (II) possesses a non-bonded 3-hydroxy group and hence exhibits keto-enol tautomerism, whereas in E-rotamer (III) the 3-hydroxy group is strongly hydrogen bonded with the carbonyl of the 4-ester group and does not exhibit keto-enol tautomerism. Since these is a free rotation of the carboxylate group about the single bond to the C 4 -carbon ##STR3## Z-rotamer, would tend to transform into the more stable configuration, i.e., into E-rotamer when dissolved in organic solvents. Hence, when Z-rotamer (II) is dissolved in an organic solvent such as DMSO or DMF and re-precipitated back, it provides E-rotamer (III).
The physical and chemical properties of Z- and E-rotamers of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxy-cephem carboxylate-1-oxide are summarized in the following table.
______________________________________PHYSICAL AND CHEMICAL PROPERTIES OF Z- ANDE-ROTAMER OF p-NITROBENZYL-7-PHENOXYACETA-MIDO-3-HYDROXY CEPHEM-4-CARBOXYLATE-1-OXIDEPROPERTIES Z-ROTAMER E-ROTAMER______________________________________Description White crystalline White crystalline powder powderMelting point 163-165° C. 110-115° C.Solubility in Insoluble in EtOAc, Soluble in CHCl.sub.3,Organic Solvents CH.sub.2 Cl.sub.2, CHCl.sub.3 etc. CH.sub.2 Cl.sub.2 , etc.On Heating in Gives E-rotamer Remains unchangedOrganic Solvents(CH.sub.2 Cl.sub.2 /MeOH)Reaction with Gives E-rotamer Remains unchangedInorganic orOrganic BaseChemical Gives p-nitrobenzyl- Gives p-nitrobenzyl-reactivity towards 7-amino-3-chloro- 7-phenoxy-acetamido-triphenyl cephem-4-carboxylate 3-chloro-cephem-phosphite.Cl.sub.2 4-carboxylatecomplexIR (KBr) 3300,1770,1755,1710, 1780,1690,1680,1600, 1680,1600,1525,1350, 1520,1380,1200,1040, 1220,1030,835,750, 850,750,735,690 cm.sup.-1 680 cm.sup.-1FAB MASS M/Z 289(27.62),307(24.20), 289(20.86),307(27.39),(% INT) 412(45.48),426(87.42), 412(32.21),426(31.40), 426(87.42),473(44.63), 473(30.54),501(69.64), 501(61.93),502(99.11) 502(100%).______________________________________
The invention will now be described by reference to the following examples.
EXAMPLE 1
Z-ROTAMER OF P-NITROBENZYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
p-Nitrobenzyl-7-phenoxyacetamido-3-exomethylenecepham-4-carboxylate-1-oxide (10 g) was dissolved in CH 2 Cl 2 (120 ml). Ozone gas was bubbled into this solution at -20° C. to -30° C. After completion of the reaction, the mixture was stirred for 1 hour at -20° C. and 1 hour at 20° C. The solid thus separated was filtered and dried. Yield 7 g, m.p. 163°-165° C.
IR(KBR) in cm -1 : 3300 (OH), 1770 (β-lactam carbonyl), 1755 (3-carbonyl), 1710 (4-ester carbonyl), 1680 (7-amide carbonyl).
EXAMPLE 2
E-ROTAMER OF p-NITROBENZYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
p-Nitrobenzyl-7-phenoxyacetamido-3-exomethylenecepham-4-carboxylate-1-oxide (10 g) was dissolved in CH 2 C12 (120 ml). K 2 CO 3 (400 mg) was added and the solution was cooled to -20° C. to -30° C. Ozone gas was passed into the solution. The completion of the reaction was checked by TLC. The reaction mixture was further stirred for 1 hour at -20° C. and then allowed to warm up to 20°-25° C. and stirred for 3 hours. The almost clear solution was filtered to remove K 2 CO 3 . The filtrate was concentrated below 40° C. under vacuum. The residue on trituration with hexane gave a crystalline solid which was filtered and dried. Yield 9.2 g, m.p. 108°-112° C.
IR(KBR) in cm -1 : 1780 (β-lactam carbonyl), 1690 (4-ester carbonyl), 1680 (7-amide carbonyl).
EXAMPLE 3
p-Nitrobenzyl-7-phenoxyacetamido-3-exomethylenecepham-4-carboxylate-1-oxide (10 g) was dissolved in CH 2 Cl 2 (120 ml). The solution was cooled to -20° to -30° C. A stream of ozone was passed into the solution until the reaction was complete. Triethylamine (200 mg) was added. The mixture was stirred for 1 hour at -20° C. and then was allowed to warm up to room temperature (20° to 30° C.). The clear solution thus obtained was concentrated. The residue was triturated with hexane. The solid thus obtained was filtered and dried to give E-rotamer of 3-hydroxycephem compound. Yield 8.0 g.
IR(KBR) in cm -1 : 1780 (β-lactam carbonyl), 1690 (4-ester carbonyl), 1680 (7-amide carbonyl).
EXAMPLE 4
10 g of p-nitrobenzyl-7-phenoxyacetamido-3-exomethylenecepham-4-carboxylate-1-oxide was suspended in CH 2 Cl 2 (120 ml). KHCO 3 (400 mg) was added and ozone passed at -20° to -30° C. The reaction mixture was worked up as described in Example 2. Yield 9.3 g, m.p. 108°-110° C.
IR(KBR) in cm -1 : 1780 (β-lactam), 1690 (4-ester carbonyl), 1680 (7-amide carbonyl).
EXAMPLE 5
10 g of p-nitrobenzyl-7-phenoxyacetamido-3-exomethylenecepham-4-carboxylate-1-oxide was suspended in CH 2 Cl 2 (120 ml) and ozone was passed through at -20° to -30° C. After the completion of reaction, dimethylaniline (200 mg) was added, stirred for 1 hour at -20° C. and then allowed to warm up to 30° C. The solution became clear and worked up as described in Example 3. Yield 8.5 g.
IR identical with compound obtained in Example 3.
EXAMPLE 6
E-ROTAMER OF DIPHENYLMETHYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE
Through a solution of 2 g of diphenylmethyl-7-phenoxyacetamido-3-exomethylene-cepham-4-carboxylate-1-oxide in CH 2 Cl 2 (40 ml) at -20° C., a stream of ozone was passed until the reaction was complete on TLC (7 min.). The temperature of the reaction mixture was then raised to 25°-30° C. and stirred for 1.5 hours. The clear solution thus obtained was concentrated and the residue was stirred with hexane (15 ml) for 20 minutes. The solid thus obtained was filtered, washed with hexane and dried. Yield 2 g, m.p. 89°-95° C.
IR(KBr) in cm -1 : 1780 (β-lactam carbonyl), 1680 (4-ester carbonyl), 1665 (7-amide carbonyl).
EXAMPLE 7
Z AND E-ROTAMERS OF p-NITROBENZYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
Through a solution of 10 g of p-nitrobenzyl-7-phenoxyacetamido-3-exomethylene-cepham-4-carboxylate-1oxide in 150 ml of methylene chloride and 1 ml of methanol at -30° C., a stream of ozone was passed for 25 minutes. The reaction mixture was treated with 30 g of sodium bisulphite and was stirred for 1 hour at 0° C. 100 ml water was added to the above reaction mixture and was further stirred for 30 minutes at +10° C. The solid obtained was filtered, washed with 3×25 ml water and finally with 2×25 ml ethyl acetate, and then dried at 45° C. for 3 hours under vacuum. Yield 5.6 g, m.p. 158°-159° C.
IR was identical with Z-rotamer described in Example 1. Mother liquor was evaporated under reduced pressure and the volume was reduced to half. The residue (70 ml) was stirred for 2 hours in 140 ml hexane. The solid material was filtered, washed with 10 ml hexane and dried at 45° C. for 3 hours under vacuum. Yield 2.5 g, m.p. 110°-112° C. IR was identical with E-rotamer described in Example 2.
EXAMPLE 8
Z-ROTAMER OF P-NITROBENZYL-7-PHENYLACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
Through a solution of 2 g of p-nitrobenzyl-7-phenylacetamido-3-exomethylene-cepham-4-carboxylate-1-oxide in 50 ml of methylene chloride at -20° C., a stream of ozone was passed until the completion of the reaction (10 minutes). The temperature of the reaction mixture was increased to 30°-32° C. and stirred for 1.5 hours. The solid was filtered and dried at 35°-40° C. under vacuum for 2 hours. Yield 1.3 g (64.5%), m.p. 175°-183° C.
IR(KBr) in cm -1 : 1780 (β-lactam carbonyl), 1720 (4-ester carbonyl), 1660 (7-amide carbonyl).
EXAMPLE 9
CONVERSION OF Z-ROTAMER TO E-ROTAMER OF p-NITROBENZYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
1 g of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxy cephem-4-carboxylate-1-oxide (Z-rotamer) was dissolved in 9 ml of DMSO at room temperature. It was then precipitated by adding 25 ml of water under stirring. The product thus separated was filtered, washed thoroughly with water and finally with methanol, and then dried at 40°-45° C. under vacuum for 3 hours. Yield 0.85 g, m.p. 110°-115° C.
IR(KBr) in cm -1 : 1780 (β-lactam carbonyl), 1690 (4-ester carbonyl), 1680 (7-amide carbonyl).
EXAMPLE 10
CONVERSION OF Z-ROTAMER TO E-ROTAMER OF p-NITROBENZYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
2 g of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxy cephem-4-carboxylate-1-oxide (Z-rotamer) was refluxed in a mixture of 20 ml chloroform and 3-4 drops of methanol for 6 hours and then evaporated under reduced pressure until dryness. Yield 1.72 g, m.p. 112°-116° C.
IR(KBR) in cm -1 : 1780 (β-lactam carbonyl), 1690 (4-ester carbonyl), 1680 (7-amide carbonyl).
EXAMPLE 11
CONVERSION OF Z-ROTAMER TO E-ROTAMER OF p-NITROBENZYL-7-PHENYLACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
400 mg of p-nitrobenzyl-7-phenylacetamido-3-hydroxycephem-4-carboxylate-1-oxide (Z-rotamer) in 5 ml of CH 2 Cl 2 was treated with 1 drop of triethylamine at -10° C. The reaction mixture was stirred for 40 minutes and the clear solution thus obtained was evaporated under reduced pressure. Residue was stirred with 10 ml of hexane for 15 minutes and solid was filtered, washed with 2 ml of hexane and dried, and then purified with hexane/CH 2 Cl 2 . Yield 400 mg, m.p. 130°-135° C.
IR(KBr) in cm -1 ; 1781 (β-lactam carbonyl), 1654 (4-ester carbonyl and 7-amide carbonyl.
EXAMPLE 12
CONVERSION OF Z-ROTAMER TO E-ROTAMER OF p-NITROBENZYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
2 g of p-nitrobenzyl-7-phenoxyacetamido-3-hydroxycephem-4-carboxylate-1-oxide (Z-rotamer) was stirred in a mixture of 40 ml of methylene chloride and 45 mg of N,N-dimethylaniline at 30°-32° C. for 2.5 hours. Reaction mixture was then filtered, the filtrate was evaporated under reduced pressure and the residue was stirred with 15 ml of hexane for 30 minutes. The solid was filtered, washed with 5 ml of hexane and dried. Yield 1.3 g, m.p. 110°-115° C.
IR(KBr) in cm -1 : 1780 (β-lactam carbonyl), 1690 (4-ester carbonyl), 1680 (7-amide carbonyl).
EXAMPLE 13
Z-ROTAMER OF DIPHENYLMETHYL-7-PHENYLACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
Through a suspension of diphenylmethyl-7-phenylacetamido-3-exomethylenecepham-4-carboxylate-1-oxide (10 g) in a mixture of ethyl acetate (200 ml) and acetic acid (5 ml) at -25° C., a stream of ozone was passed until the reaction was complete. The excess of ozone was expelled with N 2 . Dimethylsulfide (1.78 g) was added and the resulting suspension was stirred at 0° C. for 0.5 hours. The suspension was cooled to -10° C., filtered and the solid was washed with chilled ethyl acetate (20 ml) and dried. Z-rotamer of diphenylmethyl-7-phenylacetamido-3-hydroxycephem-4-carboxylate-1-oxide was obtained as a white (4-ester carbonyl), 1650 (7-amide carbonyl).
EXAMPLE 14
CONVERSION OF Z-ROTAMER TO E-ROTAMER OF DIPHENYLMETHYL-7-PHENOXYACETAMIDO-3-HYDROXY-CEPHEM-4-CARBOXYLATE-1-OXIDE
2 g of diphenylmethyl-7-phenoxyacetamido-3-hydroxy-cephem-4-carboxylate-1-oxide (Z-rotamer) was suspended in 100 ml of chloroform, followed by the addition of 2 ml of methanol. The reaction mixture was refluxed for one hour. Clear solution thus obtained was evaporated under reduced pressure. Yield 1.8 g (90%), m.p. 105°-110° C.
KR (KBr) cm -1 : 1786 (β-lactam carbonyl), 1684 (4-ester carbonyl), 1676 (7-amide carbonyl).
EXAMPLE 15
Z-ROTAMER OF p-NITROBENZYL-7-PHENOXYACETAMIDO-3-HYDROXYCEPHEM-4-CARBOXYLATE-1-OXIDE
Through a suspension of 10 g of p-nitrobenzyl-7-phenoxyacetamido-3-exomethylenecephem-4-carboxylate-1-oxide in 200 ml of ethyl acetate and 5 ml acetic acid, a stream of ozone was passed at -18° C. for 25 minutes. After completion of the reaction, 1.6 ml of dimethyl sulfide was added. The temperature was raised to 0°-5° C. and the mixture was stirred for 2 hours at this temperature. The solid was filtered, washed with ethyl acetate and dried. Yield 18.6 g, m.p. 163°-165° C.
IR(KBr) in cm -1 : 3300 (OH), 1770 (β-lactam carbonyl), 1755 (3-carbonyl), 1710 (4-ester carbonyl), 1680 (7-amide carbonyl).
While the invention has been described by reference to specific embodiments, this was for purposes of illustration only. Numerous alternative embodiments will be apparent to those skilled in the art and are considered to be within the scope of the invention. | A process for the manufacture of 7-acylamino-3-hydroxycephem-4-carboxylate-1-oxide in E-rotamer form (Formula III), comprises reacting a 7-acylamino-3-exomethylenecepham-4-carboxylate-1-oxide with ozone in an inert organic solvent in the presence of a catalytic amount of an organic or inorganic base at a temperature ranging from about -80° C. to about +20° C. The E-rotamer (wherein the 3-hydroxy group is strongly hydrogen bonded to the carbonyl of the 4-ester group) exhibits different chemical and physical properties from and is more thermodynamically stable than, the Z-rotamer (wherein there is no hydrogen bonding between the 3-hydroxy group and the carbonyl of the 4-ester group). | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the field of modular shelving, and in its preferred embodiment to plastic injection and blow molding shelving which includes at least one cabinet having at least one door with an interference fit coupling system.
2. Description of the Related Art
Many different types of shelving systems are known in the art, including modular metal and plastic systems which can be shipped and sold in compact packaging and erected by the consumer. For example, metal shelving units are sold that include a plurality of metal shelves and four metal corner pieces. The corners of the metal shelves are attached to the corner pieces by a bolt and nut assembly. This type of assembly requires a large number of individual pieces and specialized tools for assembly.
Other modular shelving and cabinetry is sold for organizing mail, tools, entertainment pieces, and other similar articles. This type of modular shelving and cabinetry is typically constructed from wood and/or metal in specific dimensions. Separate pieces of the modular shelving and/or cabinetry are designed to be mounted together by hardware which require screws, latches and/or bolts. Again, this type of modular shelving requires a large number of pieces. Additionally, this type of modular shelving and cabinetry is often expensive due to materials used for construction and purpose.
It is also known that such modular shelving can include one or more cabinets. Some systems include numerous drawers within the cabinet units. Others simply place a cabinet on a shelf, while yet others build the cabinet into the unit. For the latter, prior systems have required numerous component parts, resulting in higher manufacturing costs and more difficult assembly. Another disadvantage of many modular shelving and cabinetry is the lack of stability and balance. This problem is exacerbated when items are placed on or within the shelves and/or cabinetry off-center.
Accordingly, it is an objective of the modular shelving with cabinet of the present invention to provide shelving that is strong and balanced when properly erected. Another objective of the modular shelving with cabinet of the present invention is that it should be easy to assemble by having as few different parts as possible. A related objective of the modular shelving with cabinet is that it should not require specialized tools for assembly.
Yet another objective of the modular shelving with cabinet of the present invention is that it should be inexpensive to manufacture. The modular shelving with cabinet of the present invention should also eliminate the need for various components relating to the left or right side of the shelving unit. Finally, an objective of the modular shelving with cabinet is to achieve all of the aforesaid advantages and objectives without incurring any substantial relative disadvantage.
Modular shelving with cabinet that demonstrates the objectives and advantages as discussed above would represent a significant advance in this art.
SUMMARY OF THE INVENTION
The present invention overcomes the above noted disadvantages of the related art by providing a modular shelving with cabinet(s) that reduces manufacturing cost, reduces part count, and improves performance and ease of assembly. The present invention also eliminates the need for different components for the left and right side of the cabinet.
A further feature of the present invention is to provide modular shelving with cabinet(s) that requires less precise manufacturing tolerances than prior systems. This is accomplished by a coupling system used by the modular shelving with cabinet of the present invention.
A different feature of the present invention is to provide modular shelving with cabinet(s) in which each door is coupled to a vertical, tubular riser by an interference fit which inhibits unwanted door movement following assembly.
How these and other features of the invention are accomplished, individually, in combination or in various subcombinations will be described in the following detailed description of the preferred embodiment, taken in conjunction with the attached FIGURES. Generally, however, they are accomplished in a modular cabinet system including at least one shelf having sockets at its corners and vertically positioned risers coupled to the sockets to space the shelves apart. In the preferred embodiment, the risers are tapered and nest within one another to permit stacking multiple cabinets when erecting the modular shelving with cabinet. Each cabinet in the system preferably includes two side wall panels, a rear wall panel and at least one door panel, each being coupled to the risers by having the risers pass through hollow sections of the panels and through upper and lower holes therein. The holes have a diameter equal to or just slightly less than the smallest diameter of that portion of a riser located between two shelves, and one or more radial slots is provided in the material surrounding the holes to allow the material to flex and accommodate larger diameter portions of the riser to provide an interference fit.
The coupling system used to couple the panels with the risers is made by providing shelving material and providing a hole that extends through a portion of the shelving material. As mentioned above, the hole has at least one slot extending radially outward from the hole. The hole may be provided by methods known in the art including cutting the shelves material, or by blow molding the shelving material to include a raised portion on the surface of the shelving material, which may be subsequently removed, by cutting or the like, to expose the hole.
Other ways in which the features of the invention are accomplished will become apparent to those skilled in the art after they have read the specification, and such other ways are deemed to fall within the scope of the present invention if they fall within the scope of the claims which follow.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a portion of a modular shelving with cabinet including a cabinet having two door panels;
FIG. 2 is a partial perspective view of a portion of one of the door panels illustrated in FIG. 1 showing a coupling system in accordance with the teachings of the present invention;
FIG. 3 is a schematic illustration of a portion of a riser and a portion of the door panel illustrated in FIGS. 1 and 2;
FIG. 4 is a perspective view of modular shelving with cabinet in accordance with the teachings of the present invention;
FIG. 5 is an exploded view of the modular shelving with cabinet illustrated in FIG. 4;
FIG. 6 is a perspective view of an alternate embodiment of modular shelving with cabinet in accordance with the teachings of the present invention; and
FIG. 7 is an alternate perspective view of the modular shelving with cabinet illustrated in FIG. 6 showing doors panels in an open position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Before beginning the detailed description of the preferred embodiment, several general comments can be made about the applicability and the scope of the present invention.
First, while a modular shelving with cabinet is shown which includes tubular risers, the risers need not be tubular to take advantage of the present invention. For example, the risers may have a rectangular, polygonal, triangular or circular cross-section, and the cross-section may be substantially uniform or may alternate between geometric designs as known in the art.
Second, a modular shelving with cabinet is shown with at least two doors. However, the modular shelving with cabinet of the present invention may have only one door to take advantage of the present invention.
Third, blow molded panels are preferred for use in the modular shelving with cabinet, including side, back and door panels. However, other molding techniques can be used as long as they provide a thickness suitable for receiving a riser therethrough.
Fourth, while polyethylene is the preferred material for the blow molded panels, other plastics and deformable materials may be employed.
Fifth, risers employed in the present invention may have a taper of approximately {fraction (1/16)} th of an inch to ¼ th of an inch between adjacent shelf sockets. However, the amount of taper, or whether a taper exists at all, can be varied by one skilled in the art after they appreciate the present invention.
Sixth, while the preferred and illustrated embodiment shows a coupling system with a hole having four slots extending radially therefrom, the number of slots can be as few as two and can be a greater number, e.g., eight or more. Furthermore, the length of the slot can widely vary, being determined primarily by product geometry. Preferably, the slot should be about ⅛ th of an inch or greater, and in the preferred embodiment is closer to ½ of an inch for each slot.
Lastly, the illustrations show that side panels of the modular shelving with cabinet do not extend over the edges of the shelves but extend between them. On the other hand, the door panels are constructed and arranged to have flanges at their upper and lower surfaces which cover the front edges of the shelves. The modular shelving with cabinet may be altered by having the side panels also constructed to conceal the shelving edges and/or the door panels may be constructed to fit within the space defined by the shelves.
Proceeding now to a description of FIG. 1, a modular shelving with cabinet 10 is shown, and includes a first shelf 12 , a second shelf 14 and an upper shelf 16 . More shelves can be employed and additional cabinet systems can be stacked upon one another as will be later shown and described. Risers 17 are located at each corner of the shelves 12 , 14 , and 16 and serve to space the shelves apart from one another and to support loads placed thereon. The risers 17 also serve to raise the shelves 12 , 14 , and 16 off the ground. In the preferred embodiment, the risers 17 are arranged so that they taper from the top to the bottom so that they are capable of being nested with respect to adjacent risers. For example, the riser designated by reference numeral 17 in FIG. 1 can have its lower end nest in the upper end of a riser situated below it, while the upper end may receive the lower end of a different riser.
The risers 17 extend through each shelf 12 , 14 , and 16 at sockets 19 . Sockets 19 are located at the corner of each shelf and serve to receive the upper and lower ends of the risers 17 . The socket geometry can be any known to this art, including without limitation substantially circular, rectangular, polygonal, or triangular geometry. However, in the preferred embodiment, the sockets 19 are substantially circular. In other embodiments, the sockets 19 may also be formed to permit the risers 17 to be plugged into the sockets 19 to support the shelves 12 , 14 , and 16 .
The cabinet components of the present invention include side panels 22 (only the left one of which is shown), a rear panel (which is not visible in this view) and a pair of door panels 24 and 25 . In the preferred embodiment, each of these panels are blow molded and are therefore at least partially hollow with a thickness at the panel edges adjacent to the risers greater than the riser thickness. The panels each fit over the risers 17 to assemble the shelving unit 10 and form the cabinet between shelves 14 and 16 .
In the illustrations, side panels 22 have extensions 23 at their front and rear edges, the extensions 23 being approximately one-half the height of the panel. The extensions 23 fit over risers 17 and rest upon shelf 14 . The panels are held in place, in part, by a coupling system to be described in greater detail in connection with FIGS. 2 and 3. The door panels 24 and 25 also include extensions 27 at one of its side edges, which are capable of extending over the risers 17 . The door extensions 27 are located at the top of the space between two adjoining shelves 12 and 14 . Accordingly, extensions 27 will rest upon extensions 23 as is illustrated in FIG. 1 . Similar extensions 27 extend from the rear panel (which is otherwise not shown) for coupling the rear panel to the risers 17 and to the overall shelving assembly 10 . Although the extension location is described herein, it will be apparent that other embodiments of the present invention may have side panels with extensions located at the upper half of the panel and door and rear panels with extensions at the lower half of the panels.
The side 22 and rear panels are coupled to two different risers 17 at extensions 23 and 27 , respectively, so that the side 22 and rear panels are fixed into position and may not pivot about the axis of any one riser. Conversely, doors 24 and 25 are coupled to only one riser by extension 27 , and each may pivot about the axis of a riser 17 so that it may be opened and closed. Each of the doors may also include a knob or pull 31 that may be selected by any cabinet hardware known in the art or may be integrally molded within the doors.
The coupling system of the present invention can best be appreciated by reference now to FIG. 2, which shows the extension 27 and a portion of door 24 . The top of extension 27 is a planar surface 34 , and a hole 35 is provided therein. The hole 35 passes through the extension 27 to the bottom surface of the extension 27 (which is not visible in this view). Extending radially from hole 35 are one or more slots 37 , four of which are illustrated in the preferred embodiment. From this FIGURE, it will be evident that the area between the slots 37 will have the ability to flex upwardly or downwardly with respect to the surface 34 , and provide an interference fit when used in combination with a riser 17 . The hole 35 may be formed by methods known in the art, including providing a raised surface during the blow-mold process, which is subsequently removed by cutting or the like to expose the hole 35 that extends through extension 27 . Another method of forming the hole 35 would be to cut the hole 35 within the top surface 34 and bottom surface of extension 27 .
The size of the hole 35 is selected for particular applications, but in the most preferred embodiment, it is just slightly smaller than the smallest portion of the riser that will be encountered during assembly of the component. This will provide an amount of interference at the lower end of the extension and a slightly greater amount of interference at an upper portion of the same riser, due to the taper of the riser and the fact that the holes 35 are of the same size. Preferably, the hole 35 is no larger than the smallest diameter or cross-sectional area of the riser 17 to be encountered to prevent misalignment or sagging of the various components. The invention also contemplates holes other than round holes. For example, if square risers are used, the holes would be square and the slots could extend from the corners or the sides of the holes, or both.
FIG. 3 illustrates a riser 17 extending upwardly through the hole 35 of extension 27 . The portions of the top surface 34 between slots 37 flexes to fit around riser 17 , while simultaneously applying pressure against riser 17 to hold the panel in place. The bottom surface of extension 27 is not visible in this FIGURE, but would also provide an interference fit around riser 17 through use of a hole with one or more slots.
Referring to FIGS. 4-7, a cabinet 40 according to an exemplary embodiment includes a plurality of shelves 42 supported by a plurality of risers 44 , a bottom 46 (which may also function as a shelf), and a top 48 (which may also serve as a shelf). Risers 44 engage sockets 50 at corners of shelves 42 , bottom 46 , and top 48 . According to a preferred embodiment, four risers 44 are used for each cabinet component 70 and are tubular.
Cabinet 40 also includes a plurality of side panels 52 , a plurality of rear panels 54 , and a plurality of door panels 56 . Side panels 52 and rear panels 54 include a pair of extensions 58 , 60 respectively. Each door panel 56 also includes a extension 62 . Extensions 58 , 60 , 62 are configured to receive risers 44 to couple each panel (side, rear, and door) to al least one riser 44 .
According to an exemplary embodiment, extensions 58 , 60 , 62 are configured and positioned on the panels to provide modularity and interchangeability. For example, as shown in FIGS. 4-7, extensions 58 on side panels 52 are disposed on a lower portion of the panel; extensions 60 on rear panels 54 are disposed on an upper portion of the panel; and extension 62 on door panel 56 are disposed on an upper portion of the panel. Alternatively, the extensions may be disposed on the other of the upper and lower portion. Alternatively, the extensions may alternate between the upper and lower portion on a single panel.
According to an exemplary embodiment shown in FIGS. 4 and 5, door panels 56 cover (at least partially) one shelving space 61 . According to an alternative embodiment shown in FIGS. 6 and 7, door panel 56 is configured to cover a pair of shelving spaces 61 , in which case the door panel 56 may include a pair of extensions 62 that engage risers 44 . Alternatively, the door panels may cover any number of shelving spaces (e.g., three shelves, all of the shelves, the entire front of the cabinet, etc.).
While the present invention has been described in connection with a single preferred embodiment, the invention can be variously embodied as indicated above and in other ways which become apparent to those skilled in the art after they have read this specification. Accordingly, the scope of the invention is not to be limited by reference to any particular materials, descriptions or illustrations, but is to be limited solely by the scope of the claims which will be provided for this application. | Modular shelving with at least one cabinet that includes a plurality of shelves and vertical risers which serve to space the shelves and support loads placed thereon. Cabinet side wall, back wall and door panels are installed about the risers, with each component having a pair of spaced apart holes adapted to slide over the risers. The holes preferably have a diameter just slightly less than the smallest diameter portion of the risers over which the panels will be placed, and are surrounded by one or more radial slots which allow the material around the hole to flex and accommodate larger diameter portions of the risers with an interference fit. The interference fit eliminates the need for precise hole size manufacturing and provides an additional advantage of holding the cabinet doors in a position selected by the consumer. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation-in-part of U.S. Ser. No. 10/535,805, filed Jun. 1, 2005, now U.S. Pat. No. 7,293,903 a national stage application of PCT International Application No. PCT/US04/27848, filed Aug. 27, 2004, a continuation and claiming priority to U.S. Ser. No. 60/566,042, filed Apr. 27, 2004.
FIELD OF THE INVENTION
The present invention relates to the field of glow stick units and, more particularly, to an LED and/or fiber optics illuminated glow stick.
BACKGROUND OF THE INVENTION
A glow stick is commonly known to be a small plastic tube filled with luminescent chemicals. When mechanically activated, chemical-based glow sticks will glow brightly, generally emitting a single vibrant color that is readily visible, especially in the dark.
Chemical-based glow sticks are activated by initiating a light-emitting chemical reaction within the unit, generally by bending the flexible plastic tube thereby breaking apart fragile partitions within the tube and allowing various chemicals to react. Once the chemical reaction has begun, it cannot be stopped until it has gone to completion. Chemical-based glow sticks will continue to emit light for some determinable length of time, generally on the order of several hours, after which time the glow stick will be exhausted and will no longer emit light. Exhausted chemical-based glow sticks cannot be recharged and are generally discarded after the single use.
Because of their ability to glow brightly in a vibrant color, glow sticks are very useful as safely devices for vehicles and pedestrians, especially when used at night. Moreover, glow sticks may also be highly entertaining and are commonly used as, or incorporated into, toys and novelty devices.
Although useful and entertaining, chemical-based glow sticks can only be used once after which they must be discarded. Disposable products such as chemical-based glow sticks exacerbate the growing global problem of managing excess waste. Moreover. because they are composed of plastics and liquid chemicals, chemical-based disposable glow sticks can be easily perceived as an environmental threat. Moreover, because chemical-based glow sticks cannot be repeatedly activated and deactivated, they are not well suited for incorporation into signs and other devices, such as bicycles and automobiles.
While glow sticks come in a variety of colors, a single glow stick is only capable of glowing in one color. This characteristic limits the utility and entertainment value of the device.
Electroluminescent lights are similar to glow sticks. Electroluminescent lights are generally made from glass tubes that are filled with an electroluminescent gas. When an electric current is applied, these lights glow brightly. By varying the gas used and the phosphor coating applied to the surface of the tube, electroluminescent lights can be produced that glow in a number of vibrant colors. For example, neon lights glow bright red, while fluorescent lights glow bright white.
Because electroluminescent lights can be activated and deactivated, they are well suited for lighted signs and incorporate well into other devices, such as automobiles. Electroluminescent lights are not, however, well suited for emergency use or as toys. Electroluminescent lights generally require high voltages to stimulate the electroluminescence effect. To generate these high voltages, large and relatively heavy power converters or transformers are generally required. These power converters render electroluminescent lights poorly suited for incorporation into small portable devices. Moreover, because of their relatively high-voltage and high-power consumption electroluminescent lights are not well suited for being powered by small batteries. Electroluminescent lights are also generally constructed from glass tubes. This feature, and the fact that electroluminescent lights generally require high voltage, makes them too dangerous for use as toys.
A glow stick can be used as a safety device, a toy, and as a decorative accent when incorporated into another device. For example, a glow stick can be used at night by police to direct traffic, by a distressed vehicle to signal caution to passing motorists, and by pedestrians and cyclists on the roads at night. Glow sticks can be used as a toy by young and old children, especially in dark places. Glow sticks can be mounted to automobiles and inside computers to create an eye-catching accent.
Chemical-based glow sticks manufactured from plastic tubes filled with chemicals have the disadvantages of being single-use and must be disposed of thereafter. In addition to not being environmentally friendly, these glow sticks are frequently manufactured using toxic chemicals, thereby rendering them unfit for use by children. Moreover, these chemical-based glow sticks can not be turned on and off or made to blink. Moreover, while chemical glow sticks can be manufactured in several different colors, a single glow stick is limited to glowing in one fixed color. These shortcomings of the chemical-based glow stick limit their entertainment value, as well as their usefulness as a safety device.
Electroluminescent lights generally are manufactured from glass and require a high voltage to operate. As a result, such devices are generally heavy fragile and create a risk of high-voltage electric shock and laceration by broken glass. These devices are therefore not well suited for portable use or battery operation. Moreover, these devices are also generally unfit for use by children.
OBJECT AND SUMMARY OF THE INVENTION
Accordingly, it is an objective of the present invention to provide an LED and/or fiber optics illuminated glow stick apparatus. The LED illuminated glow stick apparatus comprises at least one multicolored LED, an optically transmitting tube that illuminates when the multicolored LED is activated, control circuitry for controlling the multicolored LEDs to illuminate in multiple colors, and a soft cushion that encases the optically transmitting tube, wherein the soft cushion is at least partially transparent. In the alternative, the fiber optics illuminated glow stick apparatus comprises a light source, an optics cable in proximity to the light source that illuminates when the light source is illuminated, a control circuit for controlling the light source to be illuminated, and a protective cover that encases the optics cable.
It is another objective of the present invention to provide an LED and/or fiber optics illuminated glow stick apparatus additionally comprising an LED flashlight.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view partially in phantom of an LED glow stick in accordance with one embodiment of the present invention.
FIGS. 2A , 2 B and 2 C are perspective views, another perspective view and an elevational view, respectively, of the LED illuminated glow stick shown in FIG. 1 .
FIGS. 3A and 3B are an elevational view and a perspective view, respectively, of the LED illuminated glow stick shown in FIG. 1 .
FIG. 4 is a perspective view partially in phantom of an LED glow stick in accordance with a second embodiment of the present invention.
FIG. 5 is a phantom elevational view of a fiber optics illuminated glow stick in accordance with another embodiment of the present invention.
FIGS. 6A to 6F are elevational views of the fiber optics illuminated glow stick shown in FIG. 5 .
FIGS. 7A and 7B are perspective views of the fiber optics illuminated glow stick shown in FIG. 5 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
According to one embodiment, the present invention provides an LED illuminated glow stick that is reusable, rechargeable, capable of generating multiple colors, capable of flashing in multiple patterns, capable of being deactivated and reactivated, capable of functioning as an LED flashlight and that is portable and fit for use by children. Moreover, the LED illuminated glow sticks according to the present invention can be interlocked with one another to enhance their safety and entertainment value.
FIG. 1 shows an LED illuminated glow stick according to a preferred embodiment in a phantom view so that the interior of the glow stick can be seen. The handle 1 (or stick housing) can be constructed of a hard material such as ABS plastic and can be covered with a soft grip material such as soft rubber. The handle 1 (or stick housing) can be ergonomically built to adapt to the shape of a hand. This soft grip enhances the handling capability. Moreover, the grip may be ergonomically formed to better receive the shape of a closed hand. The soft character of the handle 1 (or stick housing) also enhances the entertainment value of the device by providing an interesting tactile experience.
A cushion 11 that is at least partially transparent or translucent is attached to the handle 1 (or stick housing) forming a single body in the form of a rectangle, a square or a “D” shape. Cushion 11 can also be formed into linear (e.g., spiked-shaped) and/or non-linear shapes (e.g., corona, wave). The cushion 11 is also formed from a soft material such as silicon, thereby enhancing the tactile experience of the device while also being capable of transmitting light. Such cushion 11 as described immediately above is considered a soft cushion. Within the cushion 11 or soft cushion is a solid light transmitting tube 10 . This tube is capable of transmitting light from the LED light sources 2 and 9 , so that the whole tube 10 can be illuminated. The tube 10 is formed from a material capable of transmitting light while illuminating, for example, acrylic can be used.
According to one embodiment of the present invention there are two multicolor LEDs 2 and 9 , one at either end of the solid tube 10 . Each multicolor LED is formed from red, blue, and green LEDs (RGB LEDs) combined together on respective control printed circuit board (PCB) 3 and 8 . Each multicolored LED 2 or 9 is capable of generating a plurality of distinct colors by turning on or off various combinations of red, blue, and green. Two multicolored LEDs 2 and 9 are together capable of generating even more colors because each individual color red, blue, and green, can be off, one on, or two on. According to another embodiment of the current invention, more than two multicolored LEDs are used. For example, up to six multicolor LEDs can be used.
The multicolored LEDs 2 and 9 can be mounted on separate LED PCB circuit boards 3 and 8 , respectively. These LED PCB circuit boards 3 and 8 are each electrically connected to the control PCB 6 containing control elements, such as an integrated circuit (IC) chip (not shown), by wire connections. Alternatively, the LEDs 2 and 9 and the control elements can be mounted on the same PCB and connected by printed circuit paths. The IC chip is capable of controlling the multicolored LEDs 2 and 9 to produce a plurality of patterns and effects, such as a single still color, a smooth transition or gradient across a range of colors, a strobe of a single color, or a switching from color to color.
A flashlight LED 13 can be built into the handle 1 (or stick housing). This flashlight LED 13 can be used to provide light to see by in dark environments when the use of a flashlight is desired. This flashlight LED 13 may be one or two multicolored LEDs and may be capable of emitting one or more colors. For example, the flashlight LED 13 may emit white light.
A switch button 4 is connected to the control PCB 6 either electrically or mechanically, such that the control IC (not shown) receives a signal when the button is pressed. The button is used to toggle between the plurality of patterns and modes and a power off or standby mode.
Multiple buttons and switches can be used to control the functioning of the glow stick, for example, a switch 14 for disconnecting the battery power may be included. This switch 14 may be a toggle switch with multiple positions. According to one embodiment of the present invention, the switch 14 can be a three position toggle switch where the up position activates the flashlight LED 13 , the down position activates the transmitting tube 10 and the center position disconnects the battery power.
Power is supplied by one or more batteries 7 located inside the handle 1 (or stick housing), as shown in FIG. 1 . These batteries may be removable or nonremovable, and may be rechargeable or non-rechargeable. In one embodiment of the present invention, three AAA sized non-removable rechargeable batteries are used. In another embodiment, a rechargable battery pack, such as a Ni-MH pack, is used.
A power input port 5 can be built into the handle 1 (or stick housing). This power input port 5 receives a low DC voltage that can be used to charge the batteries 7 or to directly power the apparatus.
According to one embodiment of the present invention, a tab 12 extends from the apparatus. The tab 12 contains a hole that can be threaded with a string to be hung, for example, around the neck of a user. Moreover, the apparatus can be attached to a. string and spun to create an amusing light pattern.
FIGS. 2A , 2 B and 2 C show additional views of the LED illuminated glow stick shown in FIG. 1 . The handle 1 (or stick housing) may consist of a top case section 21 and a bottom case section 22 to facilitate access to the batteries 7 .
FIGS. 3A and 3B show additional features of the LED illuminated glow stick shown in FIG. 1 . FIG. 3A shows a first side of the LED illuminated glow stick that was shown in FIG. 1 . Built into the handle 1 (or stick housing) are an upper hole 31 and a lower hole 32 . FIG. 3B shows a second side of the LED illuminated glow stick that was shown in FIG. 1 . Formed on the handle 1 (or stick housing) are an upper peg 33 and a lower peg 34 . The pegs 33 and 34 and holes 31 and 32 are constructed such that a first LED illuminated glow stick according to the present invention can mate with a second LED illuminated glow stick by placing a peg in a hole. In this way, two or more LED illuminated glow sticks can be mated to form a larger and more visually noticeable apparatus, thereby enhancing both the safety and entertainment values of the apparatus.
FIG. 4 shows an LED illuminated glow stick according to another embodiment. In this embodiment, a small case 43 contains the control PCB (not shown), the batteries (not shown), a button 44 , a DC power input port 45 , and one or more multicolored LEDs 41 . A transparent or translucent cushion 40 forms a single body shaped as a rectangle, a square, or a “D” shape. The small case 43 is mounted inside the cushion 40 , or alternatively, the small case 43 has approximately the same diameter as the cushion 40 and the cushion is attached to the case 43 at each end. The cushion 40 is formed from a soft material, such as silicon, thereby enhancing the tactile experience of the device while being capable of transmitting light. Such cushion 40 as described immediately above is considered a soft cushion. Within the cushion 40 or soft cushion is an optical transmitter 42 . This optical transmitter is capable of transmitting light from the LED light sources 41 throughout the body of the optical transmitter 42 so that the whole optical transmitter can be illuminated. The optical transmitter 42 is formed from a material capable of transmitting light white being illuminated, for example, acrylic can be used.
FIGS. 5 to 7 show a fiber optics illuminated glow stick according to a second preferred embodiment of the present invention. In this preferred embodiment, the light transmitting tube 10 can comprise a fiber optics device, such as an optics cable 50 as shown in FIG. 5 . The optics cable 50 can be formed in various manners. In one embodiment, the optics cable 50 can have an optical core, such as a solid optical gel core made of optically pure case acrylic monomers (e.g., MMA) to ensure flexibility and enhanced light transmission. The optical core can be clad in a sheath of clear material, such as Teflon. The optics cable 50 can have various dimensions, such as a diameter of about 7.0 mm with a variation of 0.4 mm. In an alternative embodiment, the optics cable 50 can be made of one or multiple strands of fiber optics (not shown). The fiber optics can be held together to form a signal core by various methods, such as sonic welding.
In one embodiment, the optics cable 50 can be formed as a sidelight fiber optics cable, which allows light to be partially or entirely transmitted through the cable cladding material. The optics cable 50 can be formed to have various optical chracteristics, such as the following:
Spectral Range: about 370 NM to about 690 NM (i.e., visible wavelength range); Acceptance Angle: about 45 Degrees; Numerical Aperture: about 0.68; Glass Transition Temperature: about 53.8° C.; and/or Attenuation: Less than 3% per meter.
The optics cable 50 can be be mounted in the glow stick in various manners. In one embodiment, the optics cable 50 can have its ends ultrasonically welded inside a housing made of tough engineering plastic material, such as polycarbonate. In another embodiment, a protective cover 60 can be provided, in which the optics cable 50 is placed within protective cover 60 . The protective cover, which may be clear, can be formed and mounted onto the handle 1 (or stick housing) in various conventional manners.
A light source 70 , such as one or more LEDs described above, can be directly mounted at the ends of the optics cable 50 to create light effects. In one embodiment, a three-in-one (RGB) SMT LEDs can be mounted at each end of the optics cable 50 to create colored lighting effects. It will be appreciated that various other types of light sources, such as other LEDs (e.g., quantum dot LED), cold cathodes, electroluminescence, fluorescence, can also be used to create light effects. In one embodiment, the light source can be encased in protective cover 60 (not shown).
It is to be understood that the foregoing is presented by way of example only and that many variations and adaptations may be made by one with skill in the art, so that the scope of the invention is limited only by the appended claims. | The present invention provides a fiber optics illuminated glow stick apparatus comprising at least one multicolored LED, an optics cable in proximity to the multicolored LED that illuminates when the LED is illuminated, a control circuit for controlling the multicolored LED to be illuminated, and a protective cover being mounted to a stick housing and encasing at least a part of the optics cable therein. The present invention also provides a fiber optics illuminated glow stick apparatus comprising a light source, an optics cable in proximity to the light source that illuminates when the light source is illuminated, a control circuit for controlling the light source to be illuminated, and a protective cover that encases the optics cable. The fiber optics illuminated glow stick can glow in a variety of different colors and is reusable and rechargeable. The fiber optics illuminated glow stick may additionally include an LED flashlight. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This Application claims priority to European Patent Application Number 15183808.3 filed Sep. 4, 2015, to Andreas Mader, et al., currently pending, the entire disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to a tray sealer.
BACKGROUND OF THE INVENTION
[0003] DE 10 2008 030 510 A1, DE 10 2010 027 211 A1, and DE 10 2012 015 401 A1 disclose tray sealers with tray grippers which are integrally configured and, during their movement in the direction of transport, convey several unsealed trays into a sealer. The tray grippers also convey trays sealed with a top film out of the sealer. Such tray sealers are equipped with sealing tools that, when viewed in the direction of production, become increasingly longer to further enhance the performance of these machines The tray grippers also become correspondingly longer. With an extension of the sealing tool, for example, from 800 mm to 1100 mm, the tray gripper must, for example, be extended from 1600 mm to 2200 mm. Different tray grippers and sealing tools are commonly used for different tray shapes. Tray grippers and sealing tools, when not being used in a tray sealer, are mounted on tool trolleys which are frequently moved to special rooms outside the production area of the tray sealer for maintenance or for cleaning purposes. The length of the tray grippers can pose an obstacle when driving through a door.
[0004] The length of such tray grippers can also lead to problems in adjusting them to match the trays which are provided on a supply belt for being transferred, the trays in the sealing tool, and the trays which are deposited on a removal belt. Adjustment of the tray gripper becomes increasingly complicated with an increase in its length, especially with tray sealers in which the transport level of the supply belt, the removal belt and the depositing level on a sealing tool lower part form no common level.
SUMMARY OF THE INVENTION
[0005] One object of the present invention is to provide an improved tray sealer.
[0006] The tray sealer according to one embodiment of the present invention comprises a gripper device with two gripper arms, a supply device for unsealed trays, a removal device for sealed trays and a sealing device. Each gripper arm can comprise a coupling device that is configured to hold a first tray gripper for supplying trays into the sealing device and a second tray gripper for removing trays from the sealing device. Due to a separation of the two gripper arms, which are intended for different functions and are in different spatial workspaces, the length as compared to prior art tray grippers is approximately halved so that tool lengths above 1200 mm, for example, are possible. The tray grippers can therefore be better handled both during exchange and during transportation on a tool exchange carriage.
[0007] At the same time, the present invention may address problems associated with differing levels of the supply belt, removal belt and sealing tool lower part. For example, in one embodiment of the present invention, the first tray gripper needs only to be adjusted with respect to the supply belt and the sealing tool lower part, and the second tray gripper needs only to be adjusted with respect to the sealing tool lower part and the removal belt.
[0008] The first and the second tray gripper may each be attachable to the coupling device of the gripper arm by way of a first and a second holding element. This may permit connection of the tray gripper to the gripper arm without play and in a torsion-resistant manner. Preferably, this attachment is carried out without a wrench.
[0009] In one embodiment of the present invention, at least one holding element is adjustable at the tray gripper in such a manner that the tray gripper can be oriented with respect to a first, a second and/or a third transport level. The tray gripper can therefore be adjusted in its orientation relative to the position of the trays. Two tray grippers arranged and interacting on both sides of a lane of successive trays can be adjusted relative to each other in such a manner that all trays to be picked up out of a group of trays are gripped with approximately the same force. The three transport levels can be oriented parallel to each other, but have different vertical distances. The first tray grippers can be oriented relative to the first and the second transport level, and the second tray gripper can be oriented relative to the second and the third transport level each in an optimized manner.
[0010] In one embodiment, at least one holding element is adjustable at the tray gripper in two mutually perpendicular axes in such a manner in order to be able to adjust the tray gripper in a vertical plane and a horizontal plane.
[0011] The holding elements can be configured such that torques, being generated by forces acting upon the tray gripper, are absorbed by the coupling device so that the first and the second tray grippers, respectively, of a common side, together with the two corresponding tray grippers of a second opposite side, generate a symmetry of forces within the gripper device during the process of gripping and transporting the trays.
[0012] In one embodiment, two holding elements are provided for every tray gripper and interact as a two-point attachment with the coupling device of the gripper arm, preferably without play.
[0013] In another embodiment, a single holding element is provided and configured to be wedge-shaped and/or prism-shaped to allow for a connection without play of the tray gripper to the coupling device.
[0014] The first and the second tray grippers may each be connectable to their associated coupling device in an independently detachable manner.
[0015] Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.
DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0016] In the following, an advantageous embodiment of the invention is further illustrated using a drawing, where:
[0017] FIG. 1 is a perspective view of a tray sealer according to one embodiment of the present invention;
[0018] FIG. 2 is a perspective view of a gripper device according to one embodiment of the present invention; and
[0019] FIG. 3 is a perspective view of a coupling and a holding element according to one embodiment of the present invention.
[0020] Same components are designated with the same reference numerals throughout the figures.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. For purposes of clarity in illustrating the characteristics of the present invention, proportional relationships of the elements have not necessarily been maintained in the drawing figures.
[0022] The following detailed description of the invention references specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The present invention is defined by the appended claims and the description is, therefore, not to be taken in a limiting sense and shall not limit the scope of equivalents to which such claims are entitled.
[0023] FIG. 1 shows a tray sealer 1 according to one embodiment of the present invention with a supply device in the form of a supply belt 2 , a sealing device 3 and a removal device in the form of a removal belt 4 , which are arranged consecutively in this order in a direction of production P. Furthermore, tray sealer 1 can comprise a machine frame 5 , a film feeder 6 and a film trim winder 7 . A gripper device 8 with two gripper arms 9 and respectively a first 10 and a second tray gripper 11 may be provided on both sides in the direction of production P for transporting trays 12 . In one embodiment, an operator can influence all processes of tray sealer 1 via an operating device 13 .
[0024] During operation, trays 12 may be transported on the supply belt 2 and on the removal belt 4 into and out of the sealing device 3 , respectively. In the sealing device, trays 12 are, for example, filled with a product, evacuated, flushed with gas, sealed with a top film 14 and cut. The trimmed film residue, also referred to as residual film lattice, may be wound onto film trim winder 7 .
[0025] As best illustrated in FIG. 1 ,the upper portion of supply belt 2 forms a first transport level E 1 , a sealing tool lower part 3 a of sealing device 3 for depositing trays 12 forms a second transport level E 2 , and the upper portion of removal belt 4 forms a third transport level E 3 .
[0026] Transfer of trays 12 between the supply belt 2 , sealing device 3 and removal belt 4 can be performed by gripper device 8 , which is illustrated in FIG. 2 in more detail.
[0027] FIG. 2 shows the gripper device 8 according to one embodiment of the present invention with two gripper arms 9 movable in and opposite to the direction of production P and arranged laterally relative to trays 12 to be transported. The gripper arms 9 can each comprise a coupling device 15 in their lower region. The first tray gripper 10 and the second tray gripper 11 may be respectively provided at each coupling device 15 consecutively in the direction of production P.
[0028] The two first tray grippers 10 may be configured such that they pick up between them a group of five trays 12 from supply belt 2 and transport the group to sealing device 3 . The second tray grippers 11 may be at the same time be configured such that they supply the group of five trays 12 , that were previously sealed with a top film 14 to a become a finished package, from the sealing device 3 to the removal belt 4 .
[0029] A pivoting motion of gripper arms 9 toward each other or away from each other about pivot axes 9 a, respectively, allows for the gripping of trays 12 from the supply belt 2 or in the sealing device 3 or for depositing trays 12 in the sealing device 3 or onto the removal belt 4 .
[0030] Both first tray gripper 10 , as well as second tray gripper 11 , can each comprise a first 16 and a second holding element 17 by use of which tray grippers 10 , 11 are attachable to and detachable from coupling device 15 without a wrench.
[0031] FIG. 3 shows a detail of coupling device 15 in an enlarged view with a holding element 16 of first tray gripper 10 in a detached state. Holding element 16 can comprise two holding bolts 20 a and 20 b which are mounted at a fixed distance relative to each other on an adjustment plate 21 . Adjustment plate 21 may be adjustably attached to tray gripper 16 by way of a bolt connection 22 . Coupling device 15 can comprise a support 23 which has two U-shaped openings 24 for receiving holding bolts 20 a, 20 b. For this purpose, holding bolts 20 a, 20 b may have a reduced diameter D at their central portion which is provided for U-shaped opening 24 in a precise fit. After inserting holding bolt 20 a, 20 b into support 23 , a spring plate 25 can ensure a reliable connection of tray gripper 16 to coupling device 15 in that spring plate 25 may enclose a holding bolt 20 a in part and at the front end. For detaching, spring plate 25 merely has to be manually pushed away from holding bolt 20 a so that tray gripper 16 can be removed.
[0032] From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims. Since many possible embodiments of the invention may be made without departing from the scope thereof, it is also to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted as illustrative and not limiting.
[0033] The constructions and methods described above and illustrated in the drawings are presented by way of example only and are not intended to limit the concepts and principles of the present invention. Thus, there has been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms “having” and “including” and similar terms as used in the foregoing specification are used in the sense of “optional” or “may include” and not as “required”. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | The invention relates to a tray sealer comprising a gripper device with two gripper arms, a supply device for unsealed trays, a removal device for sealed trays and a sealing device. Each gripper arm can comprise a coupling device that is configured to hold a first tray gripper for supplying trays into the sealing device and a second tray gripper for removing trays from the sealing device. | 1 |
This application is a continuation of now abandoned application, Ser. No. 07/504,903, filed Apr. 5, 1990.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a radio receiver used in an automobile vehicle.
2. Description of the Prior Art
As a receiver for an automobile vehicle, there is known a diversity receiver in which two antennas having a directivity different from each other are employed. In this diversity receiver, the one antenna having better receiving conditions is used for reception by switching between the antennas as disclosed in, for example, Japanese Patent Publication No. 94929/1984, in order to always receive FM broadcasting, AM broadcasting and so forth under good conditions.
Such a receiver generally comprises two antennas provided adjacent to a rear trunk of a vehicle body, a receiver unit located in a compartment of the vehicle, and a feeder connecting the receiver unit to the antennas. In this constitution, there is a problem in that the receiving condition, especially the AM broadcasting receiving condition, is not good because the length of the feeder connecting the receiver unit to the antennas is very long.
In order to solve the above problem, it might be proposed to divide the receiver unit into a tuner unit (receiver main body) and an operation unit and to provide the tuner unit adjacent to the antennas. Namely, this receiving system comprises the operation unit provided in the compartment, and the tuner unit provided near the antennas and operated by the operation unit by way of remote control, and a feeder connecting between the tuner unit and the antennas.
According to this construction, it is possible to shorten the length of the feeder thereby to suppress the generation of noises during receiving. Furthermore, the required space within the compartment for the aforementioned receiver unit can be reduced since only the operation unit is located in the compartment. With regard to the connection between the tuner unit and the operation unit, the use of a multiple line is preferable to achieve simplification of the connecting wirings.
However, even if the above mentioned noises are suppressed by adopting the technique described above, the pulse signal for operating the receiver main body (tuner unit), sent thereto from the operation unit, are received as noise by the receiver main body through the antennas, and thus the pulse signal is audibly output as noise from a speaker.
SUMMARY OF THE INVENTION
The present invention is devised in consideration of such points, and it is an object thereof to provide a receiver for a vehicle which is free of noises caused by the pulse signal sent to the receiver main body from the receiver operation unit.
In order to accomplish the above mentioned object, the present invention is characterized by comprising a receiver main body provided adjacent to an antenna mounted on a vehicle body; a receiver operation unit, provided in a compartment of a vehicle spaced from the receiver main body, for sending a pulse signal for operating the receiver main body thereto; and a control means for forcibly and continuously lowering an output derived from the receiver main body during a time in which the pulse signal is transmitted from the receiver operation unit.
In this constitution, noises caused by the pulse signal transmitted to the receiver main body from the receiver operation unit are prevented from being audibly output from a speaker.
The receiver operation unit is connected to the receiver main body by a multiple line.
The control means sends a muting signal for operating a muting circuit.
An operational signal sent from the muting circuit lowers the output from the receiver main body between the receiver main body and an amplifier or between the amplifier and the speaker.
The receiver operation unit is mounted near an instrument panel in the compartment of the vehicle.
The control means is integrated with a Phase Locked Loop circuit in one body and accomodated in the receiver main body. According to this construction, countermeasures for shielding may be easily carried out because noise generating sources of the control means and the Phase Locked Loop circuit are unified.
The antenna is disposed on a window of the vehicle body.
Furthermore, the present invention is characterised by comprising a receiver main body provided adjacent to an antenna disposed on a window of a vehicle body; a receiver operation unit, provided near an instrument panel in a compartment of a vehicle spaced from the receiver main body and connected with the receiver main body through a multiple line, for sending a pulse signal for operating the receiver main body thereto; and a control means, integrated with a Phase Locked Loop circuit in one body and accomodated in the receiver main body, for forcibly and continuously lowering an output derived from the receiver main body to operate a muting circuit by sending a muting, signal thereto from the control unit during a time in which the pulse signal is transmitted from the receiver operation unit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a compartment of a vehicle having a receiver according to the present invention,
FIG. 2 is a block diagram of a control system,
FIG. 3 through FIG. 5 are each a flowchart showing operational control, steps and
FIG. 6 is a block diagram of another embodiment of a control system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, embodiments according to the present invention will be described with reference to the drawings.
In FIG. 1, reference numeral 1 is a receiver main body which is diposed, for example, at a rear head area near a printed antenna 3 disposed on a rear window 2.
Reference numeral 4 is a receiver operation unit which is disposed near an instrument panel 5, and the receiver operation unit 4 is connected through a multiple line to the receiver main body 1.
Reference numerals 11 and 12 each denote a front speaker, and reference numerals 13 and 14 each denote a rear speaker.
Next, the receiver main body 1 will be described with reference to FIG. 2.
On the FM receiving side, radio signals are received by antennas 21 and 22 each having a directivity different from the other. Either one of the antennas 21 and 22 which is under a good receiving condition is selected by an antenna change over switch circuit 23 as described hereafter. The radio signal received by either one of the antennas 21 and 22 is applied sequentially to a front end circuit 24 (FE) (which includes a high frequency amplifier for selecting an FM received signal and converting this signal into an intermediate frequency signal, a local oscillator and a mixer), an intermediate frequency amplifier 25(IF), and an FM detector 26 (DET). The signal output from the FM detector is then applied to a noise reducer 27 (NC), a stereo demodulation circuit 28 (MPX) which separetes the FM signal into right and left stereo signals, and an amplifier 10. The thus amplified radio signal is then applied to each of speakers 11, 12, 13 and 14.
On the other hand, on the AM receiving side, a radio signal received by an antenna 31 is directly applied from an AM detection circuit 32 to the noise reducer 27, passed through the stereo demodulator 28, amplified by the amplifier 10, and applied to the speakers 11, 12, 13 and 14.
In this way, a receiving unit 41 is constituted. The receiving unit 41 is electrically connected via a multiple line 44 to a PLL (Phase Locked Loop) circuit 42 for controlling and fixing a frequency of the FM received signal selected at the front end circuit 24, and to a controller 43 for controlling the change over of the FM and AM broadcast receptions, the selection of a frequency, the change over between a stereo system and a monaural system, and so forth. The controller 43 is supplied with a pulse signal for adequate operations via an intermediate frequency amplifier 45 from the receiver operation unit 4 using a multiple line 46. Also, the controller 43 sends a muting signal to a muting circuit 29 so as to forcibly lower an output derived from the receiver main body 1 when the pulse signal is transmitted from the receiver operation unit 4, whereby the output decreased by a muting operation may not be audibly output from the speakers 11, 12, 13 and 14.
In this embodiment, the muting operation is accomplished by way of inputting an operational signal from the muting circuit 29 into the upstream side of the amplifier 10. The muting operation at the upstream side of the amplifier 10 is easier than that between the amplifier 10 and the speakers 11, 12, 13 and 14 since a voltage value at the former is smaller than that at the latter. On the other hand, FIG. 6 shows another block diagram of the control system. In the control system according to FIG. 6, the operational signal from the muting circuit 29 is input into the amplifier 10. The constitution illustrated in FIG. 6 is approximately the same as the embodiment of FIG. 2 except for the above mentioned manner of inputting the operational signal from the muting circuit 29.
Since the PLL circuit 42 controls a frequency by using pulses in the same way as the controller 43, the PLL circuit 42 forms a noise generating source together with the controller 43. To solve this, the PLL circuit 42 is integrated with the controller 43 in one body so that countermeasures for shielding can be easily carried out.
The control using the antenna change over circuit 23 will now be described with reference to FIG. 3.
At first, upon starting, an antenna flag A is reset to make A=0 (Step S1), to thereby initially select the first antenna 21. Then, an electrical field strength E is input (Step S2), and a multipath distortion Mp is input (Step S3).
Then, it is decided whether or not a rate of change of the electrical field strength E, that is, dE/dt is larger than the set value K1 (Step S4). If dE/dt is larger than K1, A=1 is effected since the first antenna 21 presently used is under bad receiving conditions (Step S5). On the other hand, if dE/dt is not larger than K1, it is further decided whether or not the multipath distortion Mp is larger than the set value K2 (Step S6). If the multipath distortion Mp is larger than the set value K2, since the first antenna 21 is under bad receiving conditions, A=1 is effected (Step S5) and the process is moved to Step S8. If the multipath distortion Mp is not larger than the set value K2, since the first antenna 21 is under good receiving conditions, the process is moved to Step S7, and the antenna flag A is held in the state A=0.
In Step S8, it is decided whether or not A=1. If A equals 1, the second antenna 22 is selected (Step S9), the first antenna 21 is switched with the second antenna 22, and the process is returned to Step S2. On the other hand, if A does not equal 1, the first antenna 21 used at present is adopted and is not switched with the second antenna 22 (Step S10), the present state is maintained and the process is returned to Step S2. According to the above, both the rate of change on the electrical field strength E and the change of the multipath distortion Mp are monitored continuously.
Accordingly, the antenna 21 or 22 which is under better receiving conditions is always selected, thereby allowing good receiving conditions to be maintained.
The operation of the receiver operation unit 4 will now be described with reference to FIG. 4.
When the operation starts, at first a counter N is reset to zero (Step S21), a transmitting data D of a pulse signal (for example, 8 bits including a start signal and an end signal) from the receiver operation unit 4 is subjected to initialization (Step S22), and it is decided whether or not either one of the operation switches in the receiver operation unit 4 is in a state ON (Step S23).
If either one of the operation switches is in a state ON, the process is moved to Step S24. On the other hand, if all of the operation switches are in a state OFF, the above mentioned decision is repeated until either one of the operation switches comes into a state ON. In Step S24, an assignment bit assigned for the turned on switch is made from a 0 level to a 1 level. In Step S25, the receiver operation unit 4 starts transmitting to the receiver main body 1, and in Step S26, it is decided whether or not an ACK signal confirming the reception at the receiver main body 1 is input to the receiver operation unit 4 from the receiver main body 1.
If the ACK signal is input to the receiver operation unit 4, the process is moved to the Return position. If the ACK signal is not input, the reading of the counter N is made to be N+1 in Step S27, and it is decided whether or not N=4 in Step S28. Here, the decision of the transmission of the ACK signal from the receiver main body 1 is repeated because there exists a case where the reception is not immediately carried out at the receiver main body 1 due to noises and so forth.
Consequently, if N equals 4, it is judged that the ACK signal has not been transmitted since the pulse signal from the receiver operation unit 4 has not been received by the receiver main body 1 due to some abnormal state. Then, a flag F1=1 for indicating an abnormality is set (Step S29), and the process is moved to the Return position. On the other hand, if N does not represent 4, the process is returned to Step S25.
Also, the control of the controller 43 is carried out as shown in FIG. 5.
At first, when the controller 43 starts, it is decided whether or not a start signal from the receiver operation unit 4 is input thereto (Step S41). If the start signal is present at the controller 43, the process is moved to Step S42. On the other hand, if the start signal is not present, the decision in Step S41 is repeated.
In Step S42, in order to prevent noises caused by the pulse signal from the receiver operation unit 4 received by the receiver main body 1 via antennas 21, 22 and 31 from being audibly output from the speakers 11, 12, 13 and 14, the controller 43 sends the muting signal to the muting circuit 29, and in response the muting circuit 29 lowers the output from the receiver main body 1.
Then, in Step S43, the controller 43 is supplied with a transmitting data D from the receiver operation unit 4, and next it is decided whether or not an end signal is input thereto not from the receiver operation unit 4 thereto (Step S44).
If the controller 43 has been supplied with the end signal, the controller 43 installed in the receiver main body 1 sends the ACK signal for confirming the reception to the receiver operation unit 4. In this state, the muting operation by the muting circuit 29 is removed in Step S46 because there is no possibility that noises caused by the pulse signal received by the receiver main body 1 via antennas 21, 22 and 31 will be audibly output from the speakers 11, 12, 13 and 14, whereby the outputs from the receiver main body 1 are no longer to be lowered, and the process goes back to Return position. On the other hand, if the controller 43 has not been supplied with the end signal, since the possibility of an occurring abnormality exists, the reading of a counter N is made to be N+1 in Step S47, and it is decided whether or not N=4 in Step S48.
Consequently, if N equals 4, it is judged that some abnormal state exists, and the controller 43 does not transmit the ACK signal to the receiver operation unit 4. Then, a flag F2=1 for indicating an abnormality is set (Step S49), and the process is moved to the Return position. On the other hand, if N does not equal 4, the process is returned to Step S43, and the processings of Steps S43 through S48 are repeated.
In this way, when the start signal of a transmitting data D from the receiver operation unit 4 is supplied to the controller 43, the muting operation is carried out by the muting circuit 29. Therefore, noises generated by the pulse signal from the receiver operation unit 4 are not output from the speakers 11, 12, 13 and 14.
According to this invention, since the output derived from the receiver main body is forcibly and continuously lowered during a time in which the pulse signal is transmitted from the receiver operation unit, noises due to the pulse signal sent to the receiver main body are not audibly output from the speakers.
Furthermore, according to the invention, because the control means is integrated with the PLL circuit in one body and accomodated in the receiver main body, the noise generating source is unified, whereby countermeasures for shielding may be easily carried out. | A vehicular radio receiver includes a receiver main body provided adjacent to an antenna mounted on a vehicle body, a receiver operation unit provided in a compartment of the vehicle spaced from the receiver main body for sending a pulse signal for operating the receiver main body thereto, and a control circuit for forcibly and continuously lowering an output derived from the receiver main body during a time in which the pulse signal is transmitted from the receiver operation unit. Noises caused by the pulse signal transmitted to the receiver main body from the receiver operation unit are prevented from being audibly output from a speaker. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Filed of the Invention
[0002] The present invention relates to a disc apparatus being able to record or reproduce data onto/from a disc medium inserted or received in a cartridge, and in particular relates to the structure in relation to insertion, ejection or holding of the cartridge into/from/in the disc apparatus.
[0003] 2. Description of the Related Art
[0004] An example of a loading mechanism of a video camera, which uses an optical disc cartridge, in relation to the conventional art, is disclosed in Japanese Patent Laying-Open No. 2000-21059 (JP-A 21059/2000), for example. In the conventional technology disclosed, it is proposed to achieve an object to insert a disc clamper into the cartridge with certainty and accuracy, with the mechanism for holding a disc-like recording medium between a disc table and a disc clamper. The disc clamper must be disposed escaping from a moving path of the cartridge, until when the cartridge is loaded or mounted. Then, according to this publication, a disc slider 260 is provided on a disc tray 250, so as to attach the disc clamper 300 to this disc slider, thereby achieving the object mentioned above, i.e., escaping from the moving path of the cartridge. When the cartridge is loaded, the disc clamper is guided by means of a guiding slit formed in the disc tray 256 a, thereby holding the cartridge therebetween, in the structure thereof.
BRIEF SUMMARY OF THE INVENTION
[0005] As was mentioned in the above, in relation with the conventional art, for the purpose of holding the cartridge by means of the disc clamper (hereinafter, being called only by “clamper”), the disc slider is provided in an upper side, being a member separated from the disc tray. For letting this disc slider to rotate coaxially with the disc tray, parts or elements thereof must be large in the number thereof, and since the disc slider is located in an upper side of the disc tray, a whole of cartridge holder device comes to be thick in the thickness thereof.
[0006] Accordingly, an object of the present invention is to provide a cartridge holder device of a type of thinner in the thickness, in the disc apparatus, such as a optical disc video camera, etc., while reducing the number of parts of the mechanism for holding the clamper.
[0007] For achieving such the object as was mentioned above, according to the present invention, there is provided a disc apparatus, for recording or reproducing information onto/from a disc medium, by loading a cartridge, in which said disc medium is stored, in the structure threof, wherein a clamper for holding the disc medium while pressing is engaged with a clamp holder (a reinforcing plate) which opens/closed with a disc cover (an outer cover) of the exterior of the apparatus as a unit. With this, the disc slider becomes unnecessary, which was disposed for moving the clamper being held therewith.
[0008] Also, although a relative positional shift occurs between the clamper and the cartridge holder during rotation of the cartridge holder since the rotation shaft of the clamper differs from the rotation shaft of the cartridge holder, however a guide portion is formed on the cartridge holder as a unit, thereby in the structure thereof, regulating it with this, when the clamper comes close to the cartridge holder.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Those and other objects, features and advantages of the present invention will become more readily apparent from the following detailed description when taken in conjunction with the accompanying drawings wherein:
[0010] [0010]FIG. 1 is an exploded view of principle portions of an optical disc video camera, according to an embodiment of the present invention;
[0011] [0011]FIG. 2 is a perspective view of the video camera seen behind thereof, under the condition where a disc cover 5 is opened;
[0012] [0012]FIG. 3 a plane view of a cartridge 15 for user of the video camera, for explanation thereof;
[0013] [0013]FIG. 4 is a perspective view for showing the structure of a mechanical portion 14 from a right-upper side, obliquely;
[0014] [0014]FIG. 5 is a perspective view for showing the condition where the cartridge is locked on a cartridge holder after completing insertion of the cartridge;
[0015] [0015]FIG. 6 is a side view of FIG. 5;
[0016] [0016]FIG. 7 is a side view of the cartridge under the condition of being recordable or reproducible; and
[0017] [0017]FIG. 8 is a cross-section view elements of a clamper portion.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Hereinafter, embodiments according to the present invention will be fully explained by referring to the attached drawings, in particular on an optical disc video camera, for an example, for recording video and/or audio taken into onto a recoding medium, an optical disc, such as an optical disc stored or received in a cartridge, for example.
[0019] [0019]FIG. 1 shows an exploded view of the principle portions of the optical disc video camera, according to an embodiment of the present invention. An outer configure of the optical disc video camera is defined by a front case 2 , an R case 3 , an L case 4 , a disc cover 5 , a rear case 6 , an EFV portion 7 and an LCD portion, etc. On the front case 2 can be attached a lens portion 12 for picking up video viewed from the EFV portion 7 , an accessory shoe for attaching a strobe, etc., thereon, and a microphone for picking up audio. Also, the LCD portion 8 comprises a display portion being able to show or display the video picked up, the video reproduced from a recoding medium loaded, etc. On circuit boards 13 A and 13 B are formed circuits for controlling the entire operations of the optical disc video camera, such as signal processing of the video picked up through the lens portion 12 and the audio picked up through the microphone 11 , and recording the video and the audio finished with the signal processing, etc. In the mechanical portion 14 , the video and/or the audio are recorded onto the recording medium, and/or data of the video and the audio recorded is reproduced from the recording medium. Thus, with the present optical disc video camera, data of the video and the audio, etc., are recorded and/or reproduced onto/from the recoding medium, using such as an optical disc utilizing a phase change, through irradiation of lights while rotating the optical disc by the mechanical portion 14 .
[0020] [0020]FIG. 2 is a perspective view of the optical disc video camera, seen from behind thereof, under the condition that the disc cover 5 is opened. The cartridge 15 , receiving therein the recording medium, i.e., the optical disc is inserted into the cartridge holder 16 of the mechanism portion 14 , and further the cartridge is pushed into, thereby the cartridge holder 15 is locked thereon. Further, under the condition that the cartridge 15 is locked on, since a shutter 151 of the cartridge 15 (which will be mentioned later) is opened, therefore the optical disc is exposed. After locking the cartridge 15 on, when a user closes the disc cover 5 , then the cartridge 15 is loaded at the position where recording/reproducing of the video and/or audio can be made onto/from the optical disc, therefore the optical disc video camera can record and/or reproduce the video and/or the audio. For loading the recording medium, i.e., the optical disc from the condition shown in FIG. 2 to the position where the recording/reproducing can be made, the user pushes the disc cover 5 (i.e., close) by hand. Further, in the present embodiment, an upper surface, a lower surface, a front surface, a rear surface, and a right-hand and left-hand surfaces mean directions indicated in FIG. 2.
[0021] [0021]FIG. 3 is a plane view of the cartridge 15 to be used in the optical disc video camera 1 . This cartridge 15 receives the recording medium, i.e., an optical disc 156 within an inside thereof, and is constructed so that the optical disc is exposed outside through opening of the shutter 151 thereof. For the optical disc 156 received in the cartridge 15 , there are types, such as, a type on both side surfaces of which can be recorded data, such as the video and/or the audio, etc., a type on only one side surface of which can be recorded data, such as the video and/or the audio, etc., and the structure of the cartridge 15 may differ due to this difference. Herein, explanation will be given on the type on both side surfaces of which can be recorded data, such as the video and/or the audio, etc. With the structure of this type, the shutter 151 is opened on both directions, i.e., a direction A and a direction B.
[0022] Hereinafter, explanation will be given on a cartridge loading mechanism, which is equipped with the optical disc video camera 1 . FIG. 4 shows a perspective view of showing the structure of the mechanism portion 14 , seen from the right-hand upper surface side, obliquely. However, in the explanation given hereinafter, the direction of inserting the cartridge, the direction of discharging the cartridge means the directions indicated in this figure.
[0023] The mechanism portion 14 comprises, in addition to the cartridge holder 16 , a mechanism chassis 17 . The mechanism chassis 17 is fixed on the R case 3 of the optical disc video camera 1 through a shock absorption dumper not shown in the figure. On the other hand, the cartridge holder 16 is attached on the mechanism chassis 17 through a bracket attached in a rotatable relationship to the cartridge holder 16 . Further, a clump holder 18 for holding a clamper 181 with keeping a gap therebetween is attached to the disc cover 5 of the optical disc video camera. Herein, the disc cover is made of plastic; therefore a reinforcing plate(s) is for necessary for strengthening thereof. Therefore, according to the present embodiment, the clamp holder 18 is made of metal, thereby functioning a reinforcing member of the disc cover 5 made of plastic, in common. In the structure thereof, the cartridge holder 16 and the clamp holder 18 rotate into directions of the upper surface and the lower surface, respectively, accompanying with the open/close operation of the disc cover 5 . With such the structure, there is no necessity of a part for exclusive use thereof, such as the disc slider that was used in the conventional art, therefore effects can be obtained on reduction in the number of the parts, as well as, in the thickness of that portion. This FIG. 4 shows the mechanism portion 14 in the condition where the disc cover 5 is opened.
[0024] The mechanism chassis 17 has pins 171 A and 171 B, and those pins 171 A and 171 B are provided at positions, so that they are inserted into positioning bores 152 A and 152 B when the cartridge 15 inserted normally. Further, the mechanism chassis 17 comprises a pickup (not shown in the figure) for recording data of the video and/or the audio, etc., by irradiating lights upon the optical disc 156 , or reading out data of the video and/or the audio, etc., by receiving reflection light therefrom, a spindle motor 30 for rotating the optical disc 156 , and a turn table 301 being provided at a tip of said spindle motor 30 for putting or holding the optical disc 156 therebetween, collaborating with the clamper 181 , which will be mentioned later, etc.
[0025] [0025]FIG. 5 is a perspective view for showing the condition where the insertion of the cartridge 15 into the cartridge holder 16 is completed by opening the disc cover 5 (wherein the disc cover is not shown in the figure). FIG. 6 is a side view thereof, including a cross-section view of a part thereof. As was mentioned previously, the cartridge holder 16 is attached on the chassis 17 through the bracket 19 , while the chassis 17 onto the R case 3 . And, the disc cover 5 is also attached onto the R case 3 , and the fulcrum of rotational movement of the disc cover 5 is made up with a disc cover rotation shaft 186 .
[0026] The cartridge holder 16 fixes up the cartridge 16 by means of plate springs 252 A and 252 B attached to the cartridge holder 16 , thereby building up the structure, so that the cartridge 15 cannot be moved, as far as the user thereof tries to withdraw it with an intention to do so, for pulling out the cartridge 15 from the optical disc video camera. Thus, due to the fact that the user of the optical disc video camera closes the disc cover 5 from a stage where this cartridge holder 15 is fixed, the cartridge holder 16 is rotated around a cartridge holder rotation shaft 185 , from the position shown in FIG. 6 to the position shown in FIG. 7.
[0027] The clamp holder 18 of the disc cover 5 shown in FIG. 6 is bent in a portion thereof, and a link pin J 54 is fixed therein. A guide bracket 168 B provided on the upper surface of the cartridge holder 16 is engaged with a link pin B 56 provided at one end of a link 55 , the other end of which is engaged with the link pin J 54 rotatably.
[0028] At the tip side of the clamp holder 18 is fixed a pressurizing plate spring 57 , and a free height if the said pressurizing plate spring 57 is larger than the maximum distance between the clamp holder 18 and the cartridge holder 16 determined by the link mechanism mentioned above, For this reason, upon the link pin 54 and the link 55 , as well as the guide bracket 168 B are always functioned pressures, thereby they are in closely contact with one another.
[0029] When the user rotates the disc cover 5 around the disc cover rotation shaft 186 , the clamp holder 18 rotates around the disc cover rotation shaft 186 , while the cartridge holder 16 around the cartridge holder rotation shaft 185 , and the link pin B 56 moves sliding on a surface of the guide bracket 168 B. Accompanying with rotation of the disc cover 5 , there occurs difference in rotation angle between the clamp holder 18 and the cartridge holder 16 , therefore the angle defined between the clamp holder 18 and the cartridge holder 16 is large under the condition when the disc cover 5 is opened, while they are almost in parallel under the condition when the disc cover 5 is closed. However, in order to close the disc cover 5 , at the final state, it is necessary to give suppression thereon against counter force of the pressurizing plate spring 57 . As a result of this, under the condition where the disc cover 5 is opened, as shown in FIG. 6, a whole portions of the clamper 181 held on the clamper holder 18 lies in an outside (an upper side) of the cartridge holder 16 , however under the condition where the disc cover 5 is closed, as shown in FIG. 7, a predetermined portion of the clamper 181 enters into the cartridge holder in the condition thereof.
[0030] Namely, there is necessity to let the cartridge to escape from, not so as it interfere with the clamper, when inserting the cartridge, however, in the present invention, since the disc cover (an outer cover) is so constructed that the clamper is able to escape into a space defined by opening thereof, therefore there is no necessity of providing the space for escape when the disc cover is closes, thereby bringing about an effect of making thin in the thickness of the apparatus as a whole.
[0031] [0031]FIG. 7 is a side view of showing the condition where the cartridge 15 is held to be recordable or reproducible in the position thereof. The clamper 181 is mounted with a magnet not shown in the figure in a part thereof. When the optical disc 156 is to be recordable or reproducible in the position thereof, the clamper 181 holds the optical disc 156 between the spindle motor 30 , on which an iron member is mounted, due to the magnetic force of the magnet, thereby pressing it onto the turn table 301 , so as to be rotated. For this reason, when the optical disc 156 is to be recordable or reproducible in the position, there is no engagement or linkage between the clamper 181 and the clamper holder 18 , and also they are attached so as to hold the clamper 181 in a relationship of height thereof, therefore the clamper 181 operates cooperatively with closing/opening of the clamp holder 18 , i.e., goes away from the turn table 301 .
[0032] [0032]FIG. 8 shows the cross-section view of the principle portion for letting the optical disc 156 to be put or held between the clamper 181 and the turntable 301 . The height of the clamper 181 is make small in the diameter thereof, in a part on a way, in the direction of the height, and this portion of the small diameter is engaged with a recess portion 183 of the clamp holder 18 , therefore the clamper 181 will never come down therefrom, nor contact with the clamp holder 18 when the optical disc 156 rotates.
[0033] When the user of the optical disc camera tries to close the disc cover 5 to make recording or reproducing thereof, after inserting the cartridge 15 therein, a center pin 182 of the clamper 181 rides over a hub center bore 302 on the way of the rotation mentioned above, if the hub center bore 302 at the tip portion 302 of the spindle motor and the center pin 182 of the clamper 181 are not formed within a predetermined accuracy, therefore it is impossible to clamp the disc. In particular, as was mentioned previously, the clamp holder 18 , which rotates with the disc cover 5 mounting the clamper 181 thereon as a unit, is attached onto the R case 3 , while the cartridge holder 16 onto the chassis 17 , and further the chassis 17 is attached onto the R case 3 . Therefore, errors in attachment or fitting of the rotation shaft of the clamp holder (i.e., the disc cover rotation shaft) 186 and the rotation shaft 185 of the cartridge holder 16 come to be large, comparing to the conventional art where both of the shafts are same to, due to the large number of parts standing therebetween, thereby increasing a possibility that the center pin 182 may ride over the hub center bore 302 .
[0034] For this reason, guides 165 A to 165 F are formed by cutting them up from the cartridge 16 , as a unit thereof. And, a gap defined between interior surfaces of the guides 165 A to 165 F and an outer peripheral surface of the clamper, is made to equal or less than a predetermined value, thereby regulating shifting of the center thereof. The clamper 181 attached onto the clamp holder 18 moves along with the guides 165 A to 165 F provided in the cartridge holder 16 , accompanying with open/close operation of the disc cover 5 , and thereby holding the optical disc 156 between the turntable 301 of the spindle motor 30 .
[0035] In this manner, though the clamper 181 is guided with the guides 165 A to 165 F provided on the upper surface of the cartridge holder 16 , however it is further necessary to suppress a gap defined between an outer diameter of the clamper 181 and inner walls of the guides 165 A to 165 F. For this, after taking into consideration, the inner diameter of the guides 165 A to 165 F or a size for regulating a position of the clamper 181 , the portions being suppressed as far as possible is provided in a lower half of the guides 165 A to 165 F. On the other hand, for the purpose of preventing the guides 165 A to 165 F from being shifted in fore/back directions, caused due to that the clamp holder 18 is higher at the rotation center thereof than the cartridge holder 16 at the rotation center thereof and that there is also a difference in the rotation angles therebetween, when the clamper 18 is opened, and/or from an interference due to the difference in the angle between the clamper 181 and the cartridge holder 16 , upper portions of the guides 165 A to 165 F are opened in an upper direction, and the inner diameter or a size for regulating the position of the clamper 181 is larger than a lower half thereof.
[0036] In the process of rotating movement of the cartridge 16 and the clamp holder 18 mentioned above, the pins 171 A and 171 B on the mechanism chassis 17 shown in FIG. 4 are inserted into the positioning bores 152 A and 152 B, and thereby the cartridge 15 is position on the mechanism chassis 17 . Also, the cartridge 15 is inhibited from being abnormally deformed by means of a guide portion 161 of the cartridge holder 16 , when the cartridge 15 is inserted into the cartridge holder 16 in a normal direction, but if the pins 171 A and 171 B cannot enter into the positioning bores 152 A and 152 B normally due to shifting of the cartridge caused by some reasons.
[0037] Next, explanation will be made on the operation when the cartridge 15 is taken out or ejected, which is loaded inside the optical disc video camera 1 . FIG. 6 shows a perspective view of the mechanism portion 14 in the condition that the cartridge 15 loaded inside the optical disc video camera 1 can be taken out therefrom. As is apparent from the fact that the reference numerals attached in the drawings, the present condition is the same to that when the cartridge 15 is completed in the insertion thereof into the cartridge holder 16 .
[0038] Under the condition of being recordatable or reproducible shown in FIG. 7, when an eject button (mot shown in the figure) thereof, the optical disc video camera release the disc cover from the locking condition thereof. And when the user opens the disc cover 5 , the cartridge holder 16 and the clamp holder 18 movers rotationally up to the position shown in FIG. 6. In this instance, both the cartridge holder 16 and the clamp holder 18 are opened relatively while moving rotationally. In the series of operations mentioned above, the cartridge 15 comes in the condition that it can be taken out as shown in FIG. 6, while keeping the condition of the cartridge holder 15 holding the cartridge 16 therewith. The cartridge 15 is kept to be engaged or linked with, by means of the plate-like spring 251 A and 251 B, each of which shows elasticity in the direction at about perpendicular to that of the ejection of cartridge, as well as, the spring hooks 252 A and 252 B provided at the tips thereof. Therefore, the user can take out the cartridge 15 from the optical disc video camera 1 , by pulling out portions, i.e., M portion and N portion exposed or projected from the cartridge holder of that cartridge 15 , in the direction of ejection thereof, so as to release from the linkage with the spring hooks 252 A and 252 B.
[0039] As is fully explained in the above, according to the present invention, in particular in relation to the mechanism for inserting, holding and ejecting the cartridge into the cartridge holder, there can be provided a disc apparatus with a simple structure, therefore being assembled to be small in sizes with ease, while suppressing the necessary parts down to minimal.
[0040] The present invention may be embodied in other specific forms without departing from the spirit or essential feature or characteristics thereof. The present embodiment(s) is/are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the forgoing description and range of equivalency of the claims are therefore to be embraces therein. | In a disc apparatus, such as an optical disc video camera, etc., for recording or reproducing information onto/from a disc medium received in a cartridge, for obtaining reduction in a number of parts building up a mechanism for holding a clamper, thereby achieving a cartridge holder mechanism of a thinner type, wherein a clamper for holding the disc medium while pressing thereon is engaged with a clamp holder (a reinforcing plate) which opens/closes with a disc cover (an outer cover) of an exterior of the apparatus in the structure thereof. With this, With this, the disc slider becomes unnecessary, which was disposed for moving the clamper being held therewith.
Also, although a relative positional shift occurs between the clamper and the cartridge holder during rotation of the cartridge holder since the rotation shaft of the clamper differs from the rotation shaft of the cartridge holder, however a guide portion is formed on the cartridge holder as a unit, thereby in the structure thereof, regulating it with this, when the clamper comes close to the cartridge holder. | 6 |
FIELD OF THE INVENTION
The present invention relates to the manufacture of profiled elements of a material which can be brought to the viscous state. More particularly, the invention can be applied to the manufacture of fluid dispenser devices such as ink-jet printers, each including a tubular body having a terminal nozzle at one end with an orifice of predetermined cross section.
The object of the invention is to make the manufacture of the profiled elements described above easier and more economical while at the same time giving the finished product good characteristics of precision and reliability.
SUMMARY OF THE INVENTION
In order to achieve this object, the present invention provides a method for the manufacture of fluid dispensing devices including a tubular body having a terminal nozzle at one end with an orifice of predetermined cross-section, characterised in that it includes the steps of:
providing a tubular element, of a material which can be brought to the viscous state by heating and having a transverse profile substantially identical to the transverse profile of the tubular body,
effecting localised heating of an intermediate zone of the tubular element to bring the material in this zone to a viscous state,
causing deformation of the intermediate zone, resulting in a reduction in the cross-section of the internal cavity of the tubular element,
observing, during the heating, variations in the cross-section of the internal cavity of the tubular element in order to identify the condition when the cross-section reaches, at least in a transverse plane of the tubular element, a predetermined value substantially corresponding to the cross-section of the orifice of the nozzle of the dispensing device and
stopping the heating of the tubular element when this condition is reached.
The invention also provides apparatus for the manufacture of fluid dispensing devices comprising a tubular body having at one end a terminal nozzle with an orifice of predetermined cross-section, from tubular elements of material which can be brought to a viscous state by heating, having a profile substantially identical to the transverse profile of the tube of the body, characterised in that it includes:
heating means which can effect localised heating of a zone of each tubular element in order to bring the material constituting the wall of the tubular element itself to the viscous state and reduce its diameter progressively, and
detector means for observing variations in the cross-section of the internal cavity of the said zone of the tubular element during the heating; the detector means being able to identify the condition when the said cross-section reaches, at least in a transverse plane of the tubular element, a predetermined value substantially corresponding to the cross-section of the orifice of the nozzle of the dispensing device and stopping the heating of the zone of the preformed element when the said condition is reached.
The present invention further provides apparatus for the assembly of ink jet printers including an ejector with a tubular body having a nozzle at one end for projecting the ink and an annular transducer fitted onto the ejector with the interposition of a layer of hardenable resinous material in the annular cavity between the ejector and the transducer, characterized in that it includes:
a vacuum source, and
a casing defining at least one fluid-tight chamber connectible to the vacuum source; the casing having an aperture for sealingly receiving the transducer with the ejector mounted within it in an arrangement in which a first end of the annular cavity communicates with the vacuum chamber in the casing and the other end communicates with the external environment, whereby the resinous material introduced into the cavity through the other end is drawn into the cavity itself as a result of the low pressure generated in the chamber of the casing.
A further object of the present invention is to provide apparatus for detecting the size of cylindrical pieces subject to working involving variations of the transverse section of the pieces themselves, characterized in that it includes:
television monitor means which can scan a zone of the piece subject to working and subject to variations in its cross-section in order to produce an image having substantial variations of luminance in correspondence with the sides of the scanned piece; the monitor means generating, for each line of the image, a signal presenting sharp variations of amplitude in response to the substantial variations of luminance, and
measuring means which can derive an indication of the distance between the sides of the scanned piece from the sharp variations in the signal generated by the television monitor means.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, purely by way of non-limiting example, with reference to the appended drawings, in which:
FIG. 1 illustrates an ink-jet printer which can be manufactured by means of the method and the apparatus according to the invention;
FIGS. 2 to 7 illustrate schematically the steps of the method according to the invention,
FIG. 8 illustrates first apparatus according to the invention;
FIG. 9 illustrates schematically further apparatus according to the invention;
FIG. 10 is a block schematic diagram of the internal structure of one of the components of FIG. 8;
FIG. 11 illustrates typical changes with time of a signal generated within the block schematic component of FIG. 10, and
FIG. 12 illustrates an alternative form of the apparatus of FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION
In the drawings an ink-jet printer of known type is generally indicated 1 and includes a tubular ejector element 2 onto which a tubular transducer 3 is fitted.
The ejector element 2 is constituted essentially by a capillary tube having a nozzle 4 at one end with a calibrated orifice 5 for projecting the ink. The overall length of the ejector element 2 is about 1.5-2.0 cm and the capillary tube has a diameter of about 1 mm. with a wall thickness of about 5-15 hundredths of a mm. The orifice 5 typically has a diameter of about 5-8 hundredths of a mm. The ejector element 2 is normally made of a vitreous material which can be brought to a viscous state by heating such as, for example, pyrex glass.
The transducer 3 is constituted by a sleeve of piezo-electric material the internal diameter of which is reduced when an excitation voltage pulse is applied between two electrodes 6, 7 connected to respective metallized layers 8 and 9 applied to the outer surface and the inner surface of the transducer 3 respectively.
The annular space between the ejector element 2 and the inner wall of the transducer 3 contains a filling of hardenable resinous material 10 for the transmission of mechanical forces between the transducer 3 and the wall of the ejector element.
When a excitation pulse is applied to the electrodes 6 and 7, the contraction of the transducer 3 causes a corresponding contraction of the wall of the capillary tube. The effect of this contraction is to generate pressure waves within the ink which fills the ejector element 2 in use, which results in the ejection of an ink drop through the orifice 5 of the nozzle 4. A transparent epoxy resin having a low viscosity at ambient temperatures and a low heat generation upon the polymerisation may be used for the connecting layer 10, the polymersation normally being carried out at ambient or lower temperatures in order to avoid residual stresses after polymerisation. These stresses could in fact result in the ejector element 2 breaking away from the transducer element 3, rendering the printer 1 practically unusable.
One example of a resin of the type mentioned above is the resin sold under the trade name STYCAST 1277 made by Emerson and Cumming.
FIG. 2 illustrates schematically a device of known type for forming glass capillaries from borosilicate glass tubing such as pyrex glass.
In FIG. 2 a pusher member shown at P advances a borosilicate glass tube G into a heating element (muffle) indicated M.
As a result of the heating effect by the element M the glass of the tube G becomes viscous, which makes it possible to achieve, by means of a pair of counter-rotating rollers R located downstream of the element M, a drawing action which results in the formation of a glass capillary tube G 1 . A cutter member T, for example a rotary wheel, cuts the capillary tube G 1 successively into pieces each of which is indicated 11.
In FIGS. 3 and 8 a vertical-axis rotary mandrel indicated 12, receives the upper end of one of the tubular pieces 11.
In the same drawings two localized heat sources are shown at 13 which act on an intermediate portion of the capillary tube piece 11 which is rotated about its axis by the mandrel 12, which is driven by a motor 12a.
In the example illustrated in FIG. 8, the sources 13 are constituted by two hydrogen burner nozzles fed by an electrolytic generator 14.
The use of an electrolytic generator avoids the risks resulting from the use of containers such as cylinders of high pressure hydrogen gas or liquid hydrogen.
Instead of the burners 13, however, it is possible to use a heating element similar to the muffle M used in the device illustrated in FIG. 3 or other equivalent heating elements as the localised heat sources 13.
The use of a plurality of localized sources equi-angularly spaced about the vertical axis of rotation of the pieces 11 of glass capillary is, however, considered preferred at present. More particularly, the use of two opposing burner nozzles together with a speed of rotation of the mandrel 12 of about 20 revolutions per minute is considered the optimum at present.
Each of the nozzles 13 is able to effect an angular movement about a horizontal axis which allows the nozzles 13 to be oriented between an angular working position shown in full outline and indicated A in FIG. 8 and an angular rest position shown in broken outline and indicated B in the same figure.
In the angular working position A, the nozzles 13 are directed at the tubular piece 11 fixed to the mandrel 12 and cause localized heating of an intermediate zone of the piece 11 indicated 15 and illustrated on a larger scale in FIG. 4.
In the angular rest position B each of the burner nozzles 13 is directed at a respective monitoring thermocouple 16 which detects the operating temperature of the burner and acts, through a control system, not illustrated, on the generator device 14 in order to regulate the heating action achieved by the burner nozzles 13.
In the embodiment illustrated, the positions of the burner nozzles 13 and of the thermocouple 16 are such that, in the angular rest position B, the mouth of each nozzle 13 is at a distance from the respective monitoring thermocouple 16 equal to that between the mouth of the nozzle 13 itself and the zone 15 of the piece 11 subjected to heating in the angular working position A. This facilitates and makes more precise the control of the operating temperature of the burner nozzles 13 themselves.
A reservoir indicated 17 contains a stock of cut pieces 11 of glass capillary each of which constitutes the tubular starting element for the manufacture of an ejector element 2 of a printer 1 similar to that illustrated in FIG. 1.
The reservoir 17 is disposed above the mandrel 12 and communicates through a vibratory feeder 18 with the axial cavity of the mandrel 12 itself.
The tubular elements (cut pieces) 11 may thus be gravity-fed into the mandrel 12.
The axial fixing position of each preformed element 11 within the mandrel 12 is determined by the bearing of the lower end of the tubular element against a bearing plane 19 located below the mandrel 12.
The bearing plane 19 can be moved from a horizontal working position of engagement with the lower end of the tubular element 11, illustrated in full outline and indicated C in FIG. 8, to a rest position illustrated in broken outline and indicated D in the same figure.
In the rest position D, the bearing plane 19 lies in a vertical plane in order to allow the fall of the tubular element 11 into an underlying collecting receptacle 20 when the tubular element 11 is disengaged from the mandrel 12.
The orientation of the bearing plane 19 is controlled by an electrical control circuit 21 which also controls the movement of the burner nozzles 13, between their working position A and their rest positions B, and the clamping of the mandrel 12.
The control circuit 21 receives signals from an optical sensor 22 which can detect the presence of a tubular element 11 within the mandrel 12 and a detector circuit 23 connected to a television monitor camera 24 which scans the zone 15 of the tubular element 11 subject to the heating action of the burner nozzles 13. The scanned zone is illuminated by a diffuse light source 24a for example a reflection source. Preferably the camera 24 includes an optical magnification system (microscope) indicated schematically 25 in FIG. 8.
The detector circuit 23 is illustrated schematically in FIG. 10 and will be described in detail below.
With reference now to FIG. 5, a further mandrel N is intended to rotate a tubular element 11 taken from the receptacle 20 of the apparatus of FIG. 8 slowly about a horizontal axis. This element can be seen to be formed of two portions indicated 11a and 11b and corresponding respectively, when the element 11 is mounted on the mandrel 12, to the portion overlying and the portion underlying the intermediate zone 15.
A high velocity rotary cutter wheel is indicated F for separating the two portions 11a and 11b of the element 11 by cutting in a transverse plane indicated 15a.
The axial position of the wheel F is adjustable by means of a control device H controlled by a viewer W which allows the intermediate zone 15 of the element 11 mounted on the mandrel N to be observed and the image thus obtained to be superimposed on an image corresponding to a reference shape V which reproduces the shape of the nozzle 4 of ejector element 2 of the printer 1. In FIG. 6 a rotary plate 26 is shown which effects the lapping of the end face of the portion 11a of the element 11 corresponding to the ejector element 2 of the printer 1.
In FIG. 7 apparatus generally indicated U is shown for the deposition of metal evaporated under vacuum on the end face of the portion 11a of the tubular element 11 as a layer of anti-wetting material which can thus prevent the deposition of ink of the end face.
In use of the apparatus according to the invention, the tubular elements (cut of pieces 11) made by the device illustrated in FIG. 2 are loaded into the reservoir 17.
The vibratory feeder 18, under the control of the circuit 21, introduces the elements 11 sequentially into the mandrel 12 by making them fall into the mandrel 12 in its open position. The falling movement of each element 11 is arrested by the impingement of the lower end of the element 11 against the bearing plane 19 which, at the beginning of each working cycle of each tubular element 11, is in the horizontal working position C.
Immediately the optical sensor 22 detects that a tubular element 11 has been supplied to the mandrel 12, the control circuit 21 initiates the clamping of the mandrel 12 and the tipping of the bearing plane 19 downwardly into its vertical rest position D.
The mandrel 12 is subsequently rotated by means of the motor 12a while the gas nozzles 13 are brought from their angular rest positions B in which they are located originally to their working positions A in which the nozzles 13 effect localised heating of the intermediate zone 15 of the tubular element 11. In their working position A the nozzle 13 must be inclined to the axis of the mandrel in order to avoid the two flames interfering with each other. Preferably this angle is chosen to be about 60°.
As a result of the heating, the vitreous material constituting the wall of the portion 15 becomes viscous whereby, on the basis of known physical laws, the internal diameter and the outer diameter of the intermediate zone 15 of the element 11 are reduced, with a simultaneous increase in the thickness of the wall of the zone itself.
As a result of the heating the intermediate zone 15 of the element 11 thus gradually assumes the deformed hour-glass configuration illustrated schematically in FIG. 4.
The heating of the zone 15 is continued until, as a result of the deformation consequent on the vitreous material constituting the wall of the tubular element 11 changing to the viscous state, the diameter of the internal cavity of the tubular element 11 in the zone 15 reaches a value substantially corresponding to the diameter of the nozzle 5 of the ejector element 2 of the printer 1.
For the purposes of the invention it suffices for this condition to occur solely in a transverse plane of the tubular element 11. However it is preferred, for reasons which will be better described below, to achieve this condition over a certain axial length, of the tubular element itself by a suitable choice of thickness of the tube or variation of the location and inclination of the nozzles 13.
During the heating of the intermediate zone 15 the tubular element 11 is rotated by the mandrel 12 which supports the element 11 itself at its upper end so that the intermediate zone 15 which is being heated keeps its symmetry about its central axis even in the deformed hour glass configuration.
In order for the hour-glass shape to assume the desired length, the length of the tubular element and the position of the nozzles 13 are selected so that the portion 11b of the tubular element 11 beneath the zone 15 subjected to heating has a length such that the strength of the gravitational force on this portion annuls the transverse thrust due to the internal stresses generated in the material in the zone 15 which is in the visous state or balances them after this zone 15 has been moved vertically by a predetermined amount.
The correct selection of the position of the zone 15 subjected to heating is particularly important since the centrifugal forces resulting from the rotation of the tubular element 11 could have an amplifying effect on deviations of the portion 11b from the axis of the element 11 itself. The weight of the portion 11b must be such as to rectify any deviations caused by the internal stresses along the axis of the tube 11 in the zone 15.
The condition described above establishes a lower limit for the distance between the zone 15 and the lower end of the element 11. The upper limit for this distance is determined by the need to avoid the strength of the gravitational forces acting on the portion 11b being able to bring about excessive axial stretching of the wall of the zone 15 during the heating.
Given the material and the size of the ejector 2 of the printer 1 indicated above, it is preferable to choose value for the distance between the intermediate zone 15 and the lower end of the tubular element 11 of between 40 and 60 mm.
The progressive deformation of the zone 15 subjected to heating may be monitored continuously through the television camera 24 both by observation of the image produced thereby by an operator and through the detector circuit 23.
It is thus possible to discern when the degree of narrowing of the internal cavity of the tubular element has reached the desired level in the zone 15.
At this point it is possible to rotate the burner nozzles 13 towards their rest angular positions B so as to stop the heating by means of a command imparted manually to the control circuit 21 by an operator and by a signal passed to the circuit 21 by the detector circuit 23.
After a brief pause to allow the solidification of the wall of the intermediate zone 15 of the tubular element 11, the mandrel 12 is opened allowing the element 11 with its hour-glass shaped intermediate portion 15 to fall into the collecting receptacle 20.
The bearing plane 19 is then returned to the horizontal position C so as to allow a new tubular element 11 to be fed to the mandrel 12 from the reservoir 17 through the feeder 18 in order to start a new working cycle.
The tubular element 11 taken from the collecting receptacle 20 is transferred to the apparatus illustrated in FIG. 5 in which the lower end 11b of the element, which will be discarded, is mounted on the mandrel N.
It is possible to divide the element 11 into two separate portions by cutting the wall in correspondence with the plane 15a by means of the wheel F the axial position of which relative to the element 11 mounted on the mandrel N can be adjusted through the device H controlled from the viewer W.
The position of the cutting plane 15a is selected by comparison of the profile of the hour-glass zone 15 with the reference shape V which, as indicated above, reproduces the profile of the nozzle 4 of the printer element 1.
It is thus possible to carry out the cutting of the nozzle to a predetermined length with high precision, account being taken of the fact that nozzles which are too short result in the generation of ink drops in association with an excessive number of smaller size spurious droplets (satellites). Nozzles which are too long have too high an hydraulic impedance. The comparison of the zone 15 subject to cutting with the reference V also allows pieces with manufacturing defects to be discarded.
As indicated above, the zone 15 has diameters substantially corresponding to the diameters of the orifice 5 of the nozzle 4 over a certain part of its length. There is thus a field of choice for effecting the cutting of the element 11 in correspondence with an optimum plane 15a having regard to the performance of the ejector device 2.
After the portion 11a of the element 11 has been separated from the portion 11b which is to be discarded, the front face thereof surrounding the nozzle 5 is subjected to lapping as shown schematically in FIG. 6.
The lapping is preferably effected using a tinor lead-based rotary plate 26 to the surface of which is fed a diamond paste with a grain size of less than 1 micron.
At the end of the lapping, each portion 11a is cleaned and after this its internal diameter is checked and any chipping of the wall of the portion itself is looked for.
The portions 11a are subsequently mounted in the apparatus U of FIG. 7 for the vacuum-deposition on the front face thereof which has been lapped of a layer of material (anti-wetting material) for preventing the deposition of the ink on the front face during use as the ejector in an ink jet printer.
In order to apply the layer of anti-wetting material, which is normally a chromium, nickel-chromium and/or cobalt-chromium based material, it is also possible to use cathode sputtering apparatus in which the end faces of the portions 11a act as the targets.
After the deposition of the layer of anti-wetting material each portion 11a, after possible cutting of the end opposite the narrowed end, assumes the final configuration which allows its use, after coupling to a corresponding transducer 3, as an ejector element 2 in an ink jet printer.
The coupling of the ejector 2 and the transducer element 3 is achieved by means of the apparatus illustrated in FIG. 9 in which a casing is shown generally indicated 40 defining a fluid-tight chamber 41 which can be inspected visually through a transparent wall 42 with the aid of a viewer 43.
The casing 40 may usefully be made of a block of material such as plexiglass in which a blind hole defining the chamber 41 is formed.
The open end of the hole is then sealed by means of a stopper of transparent material such as plexiglass or glass which constitutes the wall 42. The stopper may be shaped like a lens in order to facilitate the optical inspection of the chamber 41.
It is also possible to form a plurality of chambers 41 in a single block of material in the manner described above so as to allow the simultaneous assembly of a plurality of jet printers.
A duct 44 puts the chamber 41 in communication with a vacuum pump 45 which can create a controlled low pressure within the chamber 41 itself.
A further aperture 46 allows the introduction into the chamber 41 of one of the ends of the transducer 3 in which the ejector element 2 is inserted.
The parts and the elements constituting the ejector 2 and the transducer 3 are indicated in FIG. 9 by the same references as used in FIG. 1.
A washer 47 is fitted to the edge of the aperture 46 to ensure sealing between the casing 40 and the outer wall of the transducer 3.
48 indicates an insert of resiliently yieldable material such as the material known as "silastic" which is aligned with the aperture 46.
The arrangement is such that the ejector 2 may be made to slide longitudinally until the nozzle 4 is brought to bear against the insert 48. Under these conditions the orifice 5 of the nozzle 4 is closed and the ejector element 2 is fixed to the casing 4 in a predetermined position.
This allows the adjustment of the axial position of assembly of the transducer 3 on the ejector element 2 very precisely.
This may be achieved, for example, by aligning a reference notch 49 provided on the outer surface of the transducer 3 with the outer edge of the aperture 46.
In the assembled disposition described, the annular cavity between the ejector 2 and the transducer 3 communicates at the end corresponding to the nozzle 4 of the ejector 2 with the chamber 41 and at its opposite end with the external environment.
This cavity may then be filled with resinous material 10 by feeding the material itself into the end of the cavity projecting from the casing 40 as shown schematically in FIG. 10, the pump 45 being operated simultaneously to create a low pressure within the chamber 41.
As a result of this low pressure, the resinous material 10 is gradually drawn into the cavity. The value of the low pressure within the chamber 41, and consequently the speed with which the material 10 fills the cavity between the ejector 2 and the transducer 3, can be adjusted so as to achieve gradual filling of the cavity itself, avoiding the formation of bubbles or irregular distribution of the material within the filling layer.
Observation of the end of the printer 1 which is within the chamber 41 through the viewer 43 makes it possible to identify when after the chamber between the ejector 2 and the transducer 3 has been filled completely, the resinous material 10 emerges from the end of the cavity corresponding to the nozzle 4.
At this point the pump 45 may be stopped to allow the hardening of the layer of resinous material 10.
This hardening is normally carried out at ambient temperature over a period of about 24 hours. In order to ensure complete hardening it is, however, preferable to subject the device 1 to a final heating phase at a moderate temperature (40°-60° C.) for a period of about 2 hours.
The printer 1, thus completed, can be connected to an ink supply tube indicated P in FIG. 9, of plastics material such as polyvinylchloride.
The connection of the tube P to the ejector element 2 is normally effected by means of a heat-shrinking sleeve (not illustrated) constituted, for example, by a piece of heat-shrinkable tube sold under the trade name RAYCHEM RNF-3000 or a piece of the tube sold under the trade name RAYCHEM UTUM.
FIG. 10 illustrates the internal structure of the detector circuit 23 of FIG. 8.
This circuit, together with the television camera 24 is usable in general for monitoring the diameter of cylindrical pieces subjected to working involving variation in the cross section of the pieces themselves. In addition to the formation of the hour-glass shaped zone 15 of the elements 11 the detector circuit 23 may also be used for the manufacture of tubes of plastics material (for example the tube for supplying the ink indicated P in FIG. 9), optical fibres and the like.
FIG. 12 shows schematically a variant of the apparatus of FIG. 2 for manufacturing such a tube. It is formed in an extrusion process by a device 36 including an orifice 37 and a core 38 which roughly define the outer diameter and the inner diameter respectively of the plastics tube P.
The final values assumed by these outer and inner diameters are, however, considerably influenced by the pulling force F exerted, for example by the winding reel 39. The tube P is monitored by a television camera 50, similar to the camera 24 of FIG. 8, which observes the outer diameter, or the inner diameter if the plastics material constituting the tube P is transparent, and provides the feedback signal for an operating mechanism 51 for the winding reel 39 to drive the latter so as to apply a force to the tube P such as to reduce its inner diameter or outer diameter until the value established by the operator is reached.
FIG. 10 shows an oscillator 26 which controls the television camera 24 of FIG. 9 through a horizontal sync generator 27, the camera being oriented so as to scan the portion 15 of the tubular element 11 subjected to heating.
The electrical signal generated by the camera 24 is characterized by variations in amplitude which correspond to the variations in luminance detectable in the scanned visual field.
In the application to the observation of the intermediate zone 15 of the element 11, which is constituted by a transparent vitreous material, these variations in luminance are present at the outer sides and the sides of the internal cavity of the tubular element 11. When the piece observed is made of an opaque material, the said variations in luminance are normally present only at the outer sides of the scanned piece.
In each case the variations in luminance are more easily detectable when the piece to be observed is illuminated with diffuse light such as that produced by the reflected light source 24a of FIG. 8. This avoids the surface of the object observed causing reflections which hinder the detection effected by the camera 24. A squaring amplifier to which the signal produced by the camera 24 is fed is shown at 28.
In the application illustrated in FIG. 8, in which the piece scanned is a tubular element of transparent material, the signal coming from the camera 24 assumes the form illustrated in FIG. 11 for each line of the image and after the squaring operation carried out by the amplifier 28.
In this signal four rectangular pulses can be seen in correspondence with the instants indicated t 1 , t 2 , t 3 , and t 4 .
More particularly, the first and last pulses (t 1 , t 4 ) indicate the presence, in the image produced by the camera 24, of two fringes generated by the total reflection of the light at the glass-air interface in correspondence with the outer sides of the tubular element 11.
The other two pulses (t 2 , t 3 ) correspond to similar fringes located at the sides of the inner cavity of the tubular element 11 itself.
The separation between the "outer" pulses (t 1 , t 4 ) is thus indicative of the outer diameter of the tubular element while the separation between the "inner" pulses (t 2 , t 3 ) indicates the inner diameter of the tubular element with an error due to refraction in the material. This error may be corrected for each time in dependence upon the material by means of a calibration circuit 33 (FIG. 10). For convenience below the signals t 2 , t 3 will be understood as the corrected signals and their separation indicates the diameter of the inner cavity of the tubular element 11 itself.
In an entirely similar manner, the separation between the pulses occurring at the instants t 1 and t 2 and the separation between the pulses occurring at the instants t 3 and t 4 are both indicative of the thickness of the wall region of the tubular element 11 scanned by the camera 24.
Differences between these two values of separation, and any phenomena of overall fluctuation of the position of the pulses, may be indicative of the existence of irregularities or asymmetry in the tubular element 11.
The output signal of the amplifier 28 is fed to a counting and timing block 29 which is synchronized with the scanning action effected by the camera 24 through a frequency signal from the generator 27.
Thus the counting and timing block 29 is able to convert the information relative to the separation of the pulses which appear in the output signal of the squaring amplifier 28 into one or more signals indicative of the transverse dimensions of the piece observed. More particularly, in the embodiment illustrated, the block 29 outputs a signal proportional to the separation between the pulses occurring at the instants T 2 and t 3 .
The output signal indicative of the internal diameter of the tubular element 11 is selected through an external control 31 for passing to a comparator 30 where it is compared with a reference level which is adjustable by means of a detector circuit 23 through the external control 31 according to the internal diameter desired for the nozzle orifice 5 (FIG. 1).
As indicated above, the television camera 24 produces a signal the form of which is illustrated in FIG. 11 for each scanning line of the image. A line counter block 34 is able to select, from all the line signals of an image, that corresponding to the transverse plane and the zone of the tubular element 11 in which it is desired to check the inner diameter of the tubular element. However, when it suffics to determine the operation on the basis of the minimum value of the diameter one may enable the counter 29 to feed to the comparator 30 all the signals generated. It is, however, possible to use various selection criteria in dependence on particular requirements of use. More particularly, when the piece of be formed is made of a material which is opaque to light a signal output by the counter 29 which is proportional to the separation of the signals occurring at the instants t 1 and t 4 (FIG. 11) is selected for passing to the comparator 30 by means of a second external control 35.
When the signal received by the comparator 30 falls below the reference level input of the comparator 30, the comparator 30 itself outputs a signal which is fed to the control circuit 21 to control, as described above, the movement of the burner nozzles 13 to their rest position and the consequent stoppage of the heating of the region 15 of the tubular element 11. This obviously occurs when the diameter of this region has reached a predetermined value selected by operation of the control 31 or 35.
By 32 is shown an anti-noise logic of known type arranged to exclude any spurious signal generated by the counter 29 in a random manner during the scanning. The logic 32 thus allows the counter 29 to output only the signals generated with a certain repetitiveness. For this purpose the logic 32 is interposed between the comparator 30 and the block 29, preventing the erroneous and undesirable switching of the comparator 30 as a result of noise signals coming from the block 29.
Naturally, the principle of the invention remaining the same, constructional details and embodiments may be varied widely with respect to that described and illustrated without thereby departing from the scope of the present invention. For example the control system with the television camera 24 may be used for various applications with or without the microscope and with continuous illumination or stroboscopic illumination. The circuit 23 may also be connected to a visual display screen and possibly to a processing computer. | The apparatus for manufacturing the ink jet glass tubes includes a vertical mandrel which receives the tubes one at a time from a feeder and rotates them relative to a pair of gas nozzles for their heating. The tube is heated in an axially limited intermediary zone so as to form an hour-glass shaped profile.
The profile of the tube is scanned by a television camera which generates two signals indicative of the internal diameter. These are compared electronically with a stored indication of the desired diameter and the two nozzles are rotated into an inactive position when this diameter is reached. The tube is cut along a plane so as to make the profile of the nozzle coincident with a reference profile by a device including an optical device connected to a cutting wheel to permit comparison of the hour-glass profile of the element with the reference profile. The severed end of the tube is then lapped and covered with a non-wettable material. The tubular element is bonded within a piezo-electric transducer, by locating the latter partially in a chamber, after fitting it over the tubular element, while a pump draws an epoxy resin through the chamber and into the space between the transducer and the tubular element. | 1 |
BACKGROUND
The present application relates to an active pixel sensor with an embedded A to D converter. More specifically, the present application describes using a flash A to D converter that has a nonlinear aspect.
FIG. 1 shows standard input/output curves of a video monitor. Curve 100 is an ideal I/O characteristic which would be completely linear between input and output. However, it is well known that most monitors have a more realistic characteristic shown as curve 102 . The lower end of the brightness scale has less gain. The upper end of the scale blooms and cuts off.
These characteristics lead to a known complementary correction being applied to the output of image devices. This correction usually has two components: a gamma (γ) correction at the lower end and knee correction at the upper end. Curve 104 shows these conventional corrections. The gamma correction increases the contrast at the lower end of the signal range to compensate for reduced gain at the lower end of the monitor responsivity characteristic. The knee correction extends the dynamic range of the monitor at the upper end.
These corrections can be done in many different ways. One correction uses nonlinear CMOS diodes which operate as nonlinear resistors. However, these processes are difficult to fabricate reliably in a CMOS process. Another way is by using a digital signal processor.
The correction must be applied at video rates, thus necessitating fast signal processing for digital output sensors.
SUMMARY OF THE INVENTION
The present system defines using an A to D converter which has an embedded correction as part of its circuitry.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects will now be described in detail with reference to the accompanying drawings, wherein:
FIG. 1 shows a standard correction system for correcting gamma and knee correction in a video system;
FIG. 2 shows the basic architecture block diagram of the preferred system;
FIG. 3 shows details of the noise reduction circuit which is used;
FIG. 4 shows a simplified block diagram of a flash-type A-to-D converter;
FIG. 5 shows a prior art diagram of a prior art resistor used in a flash converter;
FIG. 6 shows the nonuniform resistor used in a flash converter according to the present system;
FIGS. 7A and 7B show respective input voltages for different kinds of resistors;
FIG. 8 shows another embodiment of the resistor system used in the flash converter of the present invention; and
FIG. 9 shows a resultant resistor used according to this teaching.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of the embedded system is shown in FIG. 2 . Array 200 is an array of active pixel sensors of the type described in U.S. Pat. No. 5,471,515, the disclosure of which is herewith incorporated by reference to the extent necessary for proper understanding. A semiconductor substrate is formed with an image sensor, e.g., an array of photodiodes, photogates, pinned photodiodes, or, less preferably CCDs or charge injection devices (CIDs) any other image acquisition structure. Each column of the array of the active pixel sensor 200 is associated with an analog processing circuit 202 , also formed on the same substrate. The analog processing circuit is shown in further detail in FIG. 3 . The analog processor removes fixed pattern noise to produce an output that is amplified and fixed-pattern-noise-reduced. The output is A to D converted on the same substrate, by a flash A to D converter, as described herein.
The analog processing circuit of FIG. 3 operates as follows. The signal 300 from the pixel is buffered by a first transistor 302 to form a buffered signal 304 . The buffered signal 304 is applied to two parallel circuit parts: a reset leg 306 and a signal leg 310 .
The reset leg 306 samples the reset level of the active pixel. The switch 308 is closed to sample the reset level onto capacitor 312 . Then, the switch 308 is opened, leaving the reset level charged on the capacitor.
At some subsequent time, the signal switch 314 is closed thereby sampling the signal level onto the sample capacitor 316 . The switch is then opened to leave the signal level charged on the capacitor 316 .
A column is selected by closing the column select switches, shown as 320 , 322 , 324 , and 326 , in unison. This selects the column for use and applies the reset and signal values to the differential amp. At sometime thereafter, the crowbar switch 330 is closed. This has the effect of shorting together the nodes 332 and 334 respectively of the capacitors 312 , 316 . The voltage on capacitor 312 is V os +V rst − Δ V, and on capacitor 316 is V os +V site + Δ V 2 . Hence, the result output voltage becomes the average of the reset voltage (R) and the signal voltage (S) divided by two (R+S)/2. In this way, all offsets are canceled out leaving only a voltage related to the signal minus reset.
The output of the analog processor is then multiplexed to a flash Type A to D converter 204 . The flash converter is preferably of the nonlinear type as described herein. The flash converter operates at high speed to analog-to-digital convert the applied signal to form output 206 .
The flash converter can be of any desired type. However the preferred flash converter has a non-linear output characteristic.
A flash converter has the basic structure shown in FIG. 4. A resistor string 400 includes 2 n resistors 402 , 404 , where n is the desired number of bits to resolution. Each two adjacent resistors has a tap 403 therebetween. The voltage on each tap represents a specific voltage in the resistor chain based on Vcc, Vdd, and the resistances above and below the tap. The input voltage V 2 to be flash-converted is coupled in parallel to 2 n comparators shown as 406 , 408 , 410 . The comparators' output is either “1” or “0” depending on whether the input voltage to be flash-converted is greater than or less than the corresponding voltage applied thereto from the resistor ladder. Hence, the place where the voltage on the comparator outputs change from “0” to “1” represents the location of the incoming analog signal. This position is encoded by encoder 412 to form an N bit digital output where 2 n equals the number of resistors 402 , 404 . This is well known in the art.
The resistor is typically formed from a length of polysilicon or other resistive material with a known resistance. The taps 500 are attached to different locations along the polysilicon 502 as shown in FIG. 5 . This resistor is typically uniform, in the sense the resistance between any two adjacent taps is the same as the resistance between any other two adjacent taps, limited only by the resolution of the fabrication. FIG. 6 shows the resistor used in a preferred embodiment. According to this preferred embodiment, a non-uniform resistor is used in the flash A to D converter. The resistor is nonuniform in the sense that the resistance drop across some taps is different than the voltage drop across others of the taps. This nonuniform resistor forms reference voltages which are pre-weighted for both gamma correction and knee correction. The weighting is done according to known correction values.
The non-uniform resistor shown in FIG. 6 has a number of taps which are used to feed reference voltages to the comparators of the flash converter. The resistor shown in FIG. 6 is substantially wedge shaped, and hence the resistance between each two taps is different. Alternative embodiments include a discontinuous resistor such as shown in FIG. 9, explained herein. Another possibility is a resistor having the shape like that in FIG. 5, but varying spacing between the taps, to thereby vary the resistance between two adjacent taps. This nonuniform resistance allows the converter to carry out not only A to D conversion, but at the same time any predetermined weighting characteristic which can be coded into a resistive network, preferably gamma and knee correction.
While this embodiment describes the correction being used for gamma and knee correction, it should be understood that other corrections are also possible.
A second embodiment recognizes that it is difficult to implement a true gamma function in an analog circuit. The continuous gamma function is approximated by a piece wise linear curve. Hence, this second embodiment forms the gamma function using a piece-wise linear curve with a flash A to D converter that has a nonuniform resistor.
For example, let the resistance between tap point I and I—be such that Ri=5×10 −4 i 2 +0.5.
For 1V reference voltage across the resistor string, a total current of about 0.3 milliamps flows, making the total resistance about 3 K5L. The resultant non-linear characteristic of the full flash A to D converter becomes as shown in FIG. 7 A.
Implementation of a piecewise linear transfer function can be carried out by dividing the resistor string into two portions. An embodiment of this system is shown in FIG. 8 . FIG. 8 shows five different resistor parts labeled as 800 , 802 , 804 , 806 , and 808 . A switching network 820 is connected to each of the resistor parts, and is used to switch between any tap on any one resistor and any tap on any other resistor. The switching network can include a plurality of switchable transistors, each transistor connected to one of the taps, and a number of switching transistors connected to each of the switched transistors. The way in which a switching embodiment of this type would be implemented is well known in the art. The advantage is that this switching element enables any tap to be connected to any other tap.
As shown, each of the spaces between tap on 800 have a resistance of R 1 , and each of the taps on 802 have a different resistance R 2 . Similarly, the taps on 804 and 806 have different resistances. A variable tap resistor 808 could also be used as shown.
The connection line 812 schematically shows the way in which the resistors are connected to form the gamma correction. The first n taps are from resistor 802 , and the next m taps are from resistor 806 . This produces an equivalent resistor to that shown in FIG. 9 . These different resistors and resistor parts hence could be used and connected together to form any desired biasing element to the flash converter part, and hence any desired kind of compensation or correction. The switching network 820 also includes, as shown, connections to the positive voltage Vcc and to the negative voltage Vdd. Hence, each resistor string can be connected or disconnected to any reference value at any location.
The total resistance, therefore, can become any desired resistance at any desired form.
The total resistance, therefore, becomes nR 1 +mR 2 ; the total number of taps being n+m.
Several resistor chains are formed. Each has a characteristic value of ohms per tap which is constant or non constant. Each resistor string is either disconnected from or connected to either voltage reference value. Each tap may also be optionally connected across a tap point to another resistor.
The system shown in FIG. 85 hence includes a number of different switching elements. A connection may therefore pass through one or more different strings as desired. This enables forming different transfer functions depending on any desired characteristic. The transfer function can also be dynamically changed. For example, I the gamma/knee function described above, the knee point could be dynamically adjusted by switches 500 - 510 .
In the first characteristic, each resistor string has a constant number of ohms per tap. This allows a piecewise linear characteristic to be generated. The knee point and gamma point may be programmably adjusted.
Any non constant ohms per tap will give a portion of the string that is non-linear.
This approach allows the characteristic of the A to D converter to be adjusted on the fly, and hence allows gamma correction to be adjustable easily during sensor operation as the scene changes.
Although only a few embodiments have been described in detail above, other embodiments are contemplated by the inventor and are intended to be encompassed within the following claims. In addition, other modifications are contemplated and are also intended to be covered. | A non-uniform resistor is used with a flash A to D converter in order to provide an A to D output which is not linear. The nonlinearity of the A to D output is specially designed to carry out a predetermined correction of the signal. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the foreign priority benefit under Title 35, United States Code, §119(a)-(c), of Japanese Patent Application No. 2006-05685 5 , filed on Mar. 2, 2006 with the Japanese Patent Office, the disclosure of which is herein incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a drain pipe connected with a canister system installed under the floor of a vehicle on which front seats are attached.
[0003] Conventionally a vehicle is provided with a canister system to contain an active charcoal functioning as an absorbent to have fuel vapor adsorbed, as indicated, for instance, by such references as Japanese Utility Model Registration No. 2582688, Japanese Laid-open Patent Application No. H09-49460 and Japanese Laid-open Patent Application No. 2005-313667.
[0004] There is a drain pipe attached to the canister body through which cleaned air after the fuel vapor is adsorbed and removed is to be discharged into the atmosphere and air in the atmosphere is to be taken in. Generally speaking the canister system for a vehicle is installed in either an engine room of a vehicle, under a rear seat floor of a vehicle or under a front seat floor of a vehicle as indicated, for instance, by such references as Japanese Utility Model Registration No. 2582688, Japanese Laid-open Patent Application No. H09-49460 and Japanese Laid-open Patent Application No. 2005-313667.
[0005] In the case of a canister system installed in an engine room, the canister body is fixed on a vehicle body on the front side of the dash board, as indicated, for instance, by Japanese Utility Model Registration No. 2582688. A drain pipe with a lower end open, which communicates with the atmosphere, is attached to the lower part of the canister body.
[0006] In the case of a canister system installed under a rear seat floor of a vehicle, a canister body is fixed on the front side of a rear fender, while a drain filter (filter box) connected through a drain pipe (drain passage) with the canister body and a discharge pipe are installed on the rear side of the rear fender. The cleaned air after the fuel vapor is adsorbed and removed is discharged into the atmosphere through this discharge pipe.
[0007] In the case of the canister system indicated by Japanese Utility Model Registration No. 2582688 and Japanese Laid-open Patent Application No. HEI9-49460, no fuel vapor flows into a passenger room and no water comes into the canister body in case the vehicle floor is flooded with water because the canister body is located higher than the vehicle floor.
[0008] The canister system disposed under the front seat floor of a vehicle is attached in a so called center tank vehicle in which the passenger room of the rear seats is made relatively spacious and the center of gravity is located relatively low, while a fuel tank is installed under the front seat floor, as indicated by Japanese Laid-open Patent Application No. 2005-313667. Especially in the case of the center tank vehicles equipped with On-board Refusing Vapor Recovery ( to be abbreviated as ORVR hereinafter) capable of recovering fuel vapor, a canister body is installed adjacent to and in the vicinity of the fuel tank and connected with a fuel tank through a vent pipe (communication pipe). Thanks to this configuration, the fuel vapor generated from inside the fuel tank is adsorbed on the adsorbent and the air communication resistance between the fuel tank and the canister body is reduced. Moreover a drain pipe is attached to the canister body to take in air from the atmosphere when purging the canister body to have the adsorbed fuel sent to an engine.
[0009] However there is an drain opening located at a relatively low position under the vehicle floor in the case of the center tank vehicle equipped with ORVR, which is described in Japanese Laid-open Patent Application No. 2005-313667. Through this drain opening such water as from rainwater and dirt and dust are easily absorbed together with air from the atmosphere into a canister system. As a result, there is a problem with a drain filter being easily clogged.
[0010] The present invention is to solve the aforementioned problem and intended to provide the drain pipe in the canister system which is installed under the front seat floor of a vehicle, prevent the air after fuel vapor is adsorbed and removed from flowing into a passenger room and inhibit water, dirt and dust being absorbed into a drain filter.
SUMMARY OF THE INVENTION
[0011] A first aspect of the present invention provides a drain pipe in a canister system which is connected with a canister body and installed under a front seat floor of a vehicle, the drain pipe in the vehicle, comprising a first part extending from the canister body up to an upper space of an engine room disposed on a front side of a passenger room, and a second part extending from the first part to a space under the passenger room, which communicates with an atmosphere under the floor of the passenger room.
[0012] According to the first aspect of the present invention, the drain pipe has its one end connected with the canister body which is disposed under the front seat floor of the vehicle and extends to an upper portion of the engine room and further back to a portion under a floor of the passenger seat with the other end exposed to the atmosphere.
[0013] As a result, fuel vapor in the upper portion in the fuel tank is adsorbed in the canister body and the air cleaned free from the fuel vapor is transported once to the engine room and then back to under the passenger seat floor and discharged into the atmosphere without coming inside the passenger room. Moreover dirt and dust are inhibited from coming inside the canister system.
[0014] A second aspect of the present invention provides a drain pipe in a canister system according to the first aspect, further comprising a drain filter installed at or in a vicinity of a highest portion of the drain pipe in the canister system.
[0015] According to the second aspect of the present invention, a drain filter is installed at a relatively high position in the drain pipe and kept a sufficiently long distance off the road surface where there remains dirt and dust, or water. As a result, dirt and dust, or water drops are prevented from coming up to the drain filter and the drain filter is not clogged.
[0016] A third aspect of the present invention provides a drain pipe in a canister system according to the second aspect, further comprising a branch pipe which an auxiliary pipe branches from and is installed in a vicinity of the drain filter and on an atmosphere exposed side of the drain filter, wherein the branch pipe has a double concentric pipe structure.
[0017] According to the third aspect of the present invention, the drain pipe is equipped with a branch pipe from which the branch pipe branches in the vicinity of the drain filter and on the atmosphere exposed side of the drain filter and the branch pipe has a double pipe structure. Due to this double pipe structure, air coming through the drain filter is inhibited from flowing into the auxiliary pipe while air flows to and from the auxiliary pipe when the flow resistance of the main drain pipe becomes high.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The object and features of the present invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
[0019] FIG. 1 is a side elevation view briefly illustrating a fuel tank system inclusive of a drain pipe in a canister system of the present invention;
[0020] FIG. 2 is a plan view briefly illustrating a drain pipe in a canister system of the present invention;
[0021] FIG. 3 is a perspective exploded view of essential parts of a drain pipe in a canister system of the present invention;
[0022] FIG. 4 is a enlarged figure indicating a drain pipe in a canister system of the present invention seen from under a vehicle and the installation condition of a canister body;
[0023] FIG. 5 is an enlarged cross sectional view illustrating the drain pipe in a canister system seen when cut along the X-X line in FIG. 4 ; and
[0024] FIG. 6 is an enlarged cross sectional view illustrating a drain pipe in a canister system of the present invention and an essential part of a drain pipe in a canister system.
[0025] The same or corresponding elements or parts are designated with like references throughout the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0026] A drain pipe in a canister system on an embodiment of the present invention is to be explained hereinafter in detail referring to FIG. 1 through FIG. 6 . FIG. 1 indicates an approximate side view of a drain pipe in a canister system on an embodiment of the present invention.
[0027] Prior to explaining a drain pipe in a canister system on an embodiment of the present invention, a vehicle C in which a drain pipe D is installed, an explanation is made on a fuel tank T to be installed in the vehicle C, a fuel tank system A and a fuel vapor collecting unit.
Structure of the Vehicle
[0028] As described in FIG. 1 , the vehicle C in which the drain pipe D is installed is a so-called center tank vehicle in which a center of gravity is made relatively located low, a fuel tank T and a canister body 61 are installed under a floor of a front seat 1 (under a floor panel Cb) and a relatively large space is created on the back side of a passenger room R. In a vehicle like the vehicle C, a fuel replenishment inlet 3 a is located on the back side of a rear seat 2 and a filler pipe 3 and a vapor return tube 4 both of which extend from the fuel replenishment inlet 3 a to the fuel tank T are made relatively long. The floor panel Cb is located at so low a position that the rear seat 2 is folded flat to be flush with a luggage floor Ca. Therefore in order not to have the vapor return tube interfere with the floor panel Cb or others, there is a lowered portion 4 a of the vapor return tube 4 between the middle of the fuel tank T and the rear wheel. On both ends of this lowered portion 4 a the vapor return tube 4 is curved.
[0029] FIG. 2 shows a rough plan view illustrating a drain pipe in a canister system of an embodiment of the present invention.
Fuel Tank Structure
[0030] The fuel tank T shown in FIG. 1 and FIG. 2 is intended for storing fuel and a filler pipe 3 , one of whose end is connected with a fuel replenishment inlet 3 a , is connected to the fuel tank T through an inlet valve V 1 and a fuel neck tube 3 b on the rear end side of the fuel tank T. Above the fuel tank T the vapor return tube 4 , one of whose end is connected with the filler pipe 3 in the vicinity of the fuel replenishment inlet 3 a which is located at a relatively high position, is installed along the filler pipe 3 .
[0031] The vapor return tube 4 is meant for circulating a part of the air in the upper part of the inside of the fuel tank T into the filler pipe 3 in the vicinity of the fuel replenishment inlet 3 a . This vapor return tube 4 has also a function of reducing the amount of the air coming from the atmosphere into the fuel tank T through the fuel replenishment inlet 3 a and the filler pipe 3 .
[0032] As indicated in FIG. 1 and FIG. 2 there is a canister body 61 which is installed in parallel with the fuel tank T and connected with the fuel tank T through a vent pipe 14 . On the front side of the canister body 61 a drain pipe D is attached and extends through a vent shut valve V 4 to a drain filter 62 installed at an upper space in an engine room ER located on the front side of the passenger room R. The drain pipe D further extends back to the space under the floor of the passenger room R from the drain filter 62 and has the end opened and exposed to the atmosphere. The fuel tank T is installed on a lower side of the floor panel Cb under the front seats and fixed on the floor panel Cb with a couple of tank bands 12 ( see FIG. 4 ).
[0033] As indicated in FIG. 2 a pump module P, a vapor return float valve 5 , a fuel replenishment float valve 7 are installed on the upper surface of the fuel tank T. The main part of the pump module P is inside the fuel tank T. Each of the fuel replenishment float and the fuel replenishment float has a float valve which is to be closed when the fuel tank is full of fuel.
Structure of Fuel Tank System
[0034] As indicated in FIG. 2 a fuel tank system A is composed of the fuel tank T, the filler pipe 3 , the vapor return tube 4 , an intake manifold 15 , a fuel vapor collecting system B and a damage detection unit O. In the fuel vapor collecting unit B the fuel vapor generated in the upper portion of the inside of the fuel tank is transported to the canister system 6 not to have the fuel vapor come out to the outside while the fuel tank replenishment is under way. A damage detection unit O detects a hole in the pipes for the fuel tank replenishment if there is. The intake manifold 15 makes the pressure in the pipes inclusive of the fuel tank T, the filler pipe 3 and the vapor return tube 4 negative with respect to the atmosphere.
[0035] FIG. 3 shows an exploded perspective view illustrating an essential part of a drain pipe in a canister system of the present invention.
[0036] The pump module P illustrated in FIG. 3 is equipped with a suction filter not shown, a fuel pump to transport the fuel to an injector 8 shown in FIG. 2 through the fuel pipe 9 , a fuel level meter not shown to detect the fuel level in the fuel tank T and a cut valve V 3 connected with the canister body 61 through a fuel replenishment float valve 7 , a vent relief valve V 2 and a vent pipe 14 , which constitutes a whole venting line. The pump module P includes these apparatuses and its main part is installed inside the fuel tank T.
[0037] The vent relief valve V 2 is a differential pressure valve to be opened if the fuel vapor pressure increases inside the fuel tank T. The vapor return float valve 5 is to be closed not to have the fuel tank over-replenished and the fuel come into the vapor return tube 4 when the fuel tank is being replenished. The fuel replenishment float valve 7 is closed when the fuel tank T is full of the fuel and the fuel is prevented from coming into the canister body 61 .
Structure of Fuel Vapor Collecting Unit
[0038] As is indicated in FIG. 3 the fuel vapor collecting unit B is intended to circulate the fuel vapor inside the fuel tank T through the vapor return tube 4 , inhibit fuel vapor being generated from being discharged into the atmosphere by having the fuel vapor adsorbed in the canister system 6 . This fuel vapor collecting unit B is composed mainly of the vapor return tube 4 , the canister system 6 , the vent pipe 14 connecting between the canister body 61 and the fuel tank T, a drain pipe D connected with the canister system 61 and a purge pipe 19 connected from the canister system 6 to the injector 8 (See FIG. 1 and FIG. 2 ) through a purge regulating electro-magnetic valve V 5 .
Canister Structure
[0039] The canister system 6 is to temporarily collect and store the fuel vapor in the fuel tank T, to supply the intake manifold with the stored fuel vapor by having the stored fuel vapor freed with the air suctioned by the negative pressure of a engine E with respect to the atmosphere (negative pressure refers to lower pressure than the atmosphere hereinafter) as well as to prevent the fuel vapor from being discharged into the atmosphere.
[0040] The canister system 6 consists mainly of the canister body 61 , the drain filter 62 , the drain pipe D and a vent shut valve V 4 . The canister body 61 contains adsorbent. On this adsorbent adsorbs the fuel vapor which is pressurized in the upper portion the fuel tank T by the replenished fuel and transported therefrom during the fuel replenishment. The drain filter is intended for removing dirt and dust contained in the air introduced from the atmosphere during purging. The drain pipe is to connect between the canister body 61 and the drain filter 62 to supply air to the canister body 61 . The vent shut valve V 4 is installed in the drain pipe D between the canister body 61 and the drain filter 62 .
[0041] As indicated in FIG. 2 the stored fuel vapor in the canister body 61 is purged while the engine is running and suctioned into the intake manifold 15 through the purge regulating electro-magnetic valve V 5 together with air suctioned due to the negative pressure in the intake manifold 15 . ECU not shown which is connected with the purge regulating electro-magnetic valve V 5 controls the opening time of the purge regulating electromagnetic valve V 5 based on several sensor outputs and the amount of the fuel vapor to be suctioned.
[0042] The intake manifold is an air suctioning passage for the engine E, through which the cleaned air with an air cleaner is supplied to the engine E through a throttle valve not shown.
Structure of Canister Body
[0043] FIG. 4 is an enlarged view of a canister system seen from its underneath which is attached to a vehicle, indicating how the canister system is attached to a vehicle. FIG. 5 is an enlarged view of a cross section of the canister body cut along the X-X line in FIG. 4 .
[0044] As indicated in FIG. 4 and FIG. 5 the canister body 61 is installed adjacent to the fuel tank T and is connected with the fuel tank T through a vent pipe which is relatively thick and short in shape and has a small flowing resistance. The canister body 61 is attached through a rubber sheet to a bracket 63 made of a sheet of steel which is fixed on a lower side of the floor panel Cb. An attachment portion extending from the canister body 61 is not so robust as the canister body 61 . As a result, in case the vehicle undergoes a collision and the floor panel Cb is deformed, the collision shock on the canister body 61 is absorbed by the deformation of the attachment portion and the rubber and the canister body 61 is prevented from breaking.
[0045] As seen in FIG. 5 the canister body 61 is covered with a protective plate made of plastic which is fixed on the lower side of the floor panel Cb. The canister body 61 is connected with the intake manifold 15 through a purge pipe 19 in which the purge regulating electromagnetic valve V 5 is installed (See FIG. 1 to FIG. 3 ). There is an inner pressure sensor S attached to the canister body 61 and a sensor pipe 18 is attached to the inner pressure sensor S with its end opened.
Structure of Drain Filter
[0046] A drain filter 62 as indicated in FIG. 2 is intended for removing dirt and dust contained in the air suctioned from the atmosphere and is a container containing a paper filter, for instance.
[0047] The drain filter 62 is installed at the highest position of or in its vicinity of the drain pipe D in the engine room ER. This drain filter 62 is attached to the front side of the separating wall with the dash board which forms an inner wall of the engine room ER and is fixed on the separating wall with a bolt tightened onto a bracket fixed in the upper part of the engine room ER.
Structure of Drain Pipe
[0048] As seen in FIG. 1 to FIG. 3 the canister system 6 is equipped with the drain pipe D. This drain pipe D consists of a connecting pipe D 1 , an exhaust pipe D 2 , an auxiliary pipe D 3 and a branch pipe D 4 . The connection pipe D 1 connects between the canister body 61 and the drain filter 62 , and extends to an upper portion of the engine room ER. There is a vent-shut valve V 4 in this connection pipe D 1 , which is electrically connected with and controlled by ECU not shown. This vent-shut valve V 4 is closed only when the pressure of the fuel tank T is made negative.
[0049] Through the drain pipe D 2 is discharged into the atmosphere the cleaned air which comes through the drain filter 62 and fuel vapor from the fuel tank T is removed from.
[0050] In case the drain pipe D 2 is clogged, air can be discharged from the canister body 61 through the auxiliary pipe D 3 and suctioned through the auxiliary pipe D 3 and the drain filter 62 into the canister body 61 with the adsorbed fuel vapor freed in the canister body 61 and transported through the purge pipe 19 to the intake manifold 15 .
[0051] The auxiliary pipe D 3 is branched from the branch pipe D 4 which is attached in the vicinity of the drain filter 62 on the side exposed to the atmosphere.
[0052] FIG. 6 is a cross section view showing an inner structure of a drain pipe in a canister system of the present invention.
[0053] As seen in FIG. 6 the branch pipe D 3 has three joint portions, one joint portion connected with the drain filter 62 , one with the exhaust pipe D 2 and the other with the auxiliary pipe D 3 . The joint portion with the auxiliary pipe D 3 branches from the other part of the branch pipe D 3 . The branch pipe D 3 is a portion where both a flow passage from the exhaust pipe D 2 to the drain filter 62 and another flow passage from the auxiliary pipe D 3 to the drain filter 62 join.
[0054] The branch pipe D 4 includes a small diameter concentric pipe D 5 and a large diameter concentric pipe D 6 .
[0055] The large diameter concentric pipe D 6 is composed of a cylindrical member with a flange portion D 6 a and a joint portion D 6 b through which the auxiliary pipe D 3 is connected. The joint portion D 6 b is branched from the outer surface the cylindrical member.
[0056] The small diameter concentric pipe D 5 is composed of a cylindrical member with a flange portion D 5 a and a joint portion D 5 c through which the branch pipe D 4 is connected with the drain filter 62 . The flange portion D 5 a is formed in agreement with the flange portion D 6 a so that the flange portion D 5 a is coupled with the flange portion D 6 a.
[0057] Because the small diameter concentric pipe D 5 is sufficiently smaller in diameter than the large diameter concentric pipe D 6 , the small diameter concentric pipe D 5 is installed inside the large diameter concentric pipe D 6 with the flange portion D 5 a and the flange portion D 6 a in contact with each other and coupled together, which results in a double pipe structure.
[0058] Inside the branch pipe D 4 there are formed a main flow passage D 4 a and an auxiliary flow passage D 4 b . The main flow passage D 4 a is formed by the small diameter pipe concentric pipe D 5 and the portion of the large diameter concentric pipe D 6 from the opening D 5 b of the small diameter concentric pipe D 5 to the joint with the exhaust pipe D 2 . The auxiliary flow passage D 4 b consists of a space formed between an inner surface of the large diameter concentric pipe D 6 and an outer surface of the small diameter concentric surface and a branched portion connected with the auxiliary pipe D 3 .
[0059] Because the auxiliary flow passage D 4 b in the drain pipe D includes the space formed between an inner surface of the large diameter concentric pipe D 6 , which is much narrower than the main flow passage D 4 a , there is a very small amount of air flowing toward the auxiliary pipe D 3 compared with the air flowing toward the exhaust pipe D 2 in the ordinary condition. In case the flow resistance in the exhaust pipe D 2 becomes higher than in the auxiliary pipe D 3 , there flows more air toward the auxiliary pipe D 3 according to the flow resistance in the exhaust pipe D 2 .
[0060] For instance, if the vehicle is submerged in water under its floor panel Cb and the exhaust pipe D 2 filled with water and clogged, air can flow through the auxiliary flow passage D 4 b and there does not occur a problem with the fuel tank T being unable to communicate with the atmosphere.
Structure of Damage Detection Unit
[0061] The damage detection unit O is intended for detecting a hole on the fuel tank T and the pipes in the fuel tank system A if there is a hole generated, based on the inner pressure measured with an inner pressure sensor S (see FIG. 3 ). The damage detection unit determines whether or not a negative pressure is kept in the pipes in the fuel tank system A or the pressure in the pipes in the fuel tank system A is as high as the atmosphere, when the pressure in the fuel tank T and the pipes in the fuel tank system A is to be negative due to a negative pressure in the intake manifold 15 , which is caused on ECU's request during engine's operation.
[0062] The ECU is electrically connected with such parts as the vent-shut valve V 4 , the purge regulating electromagnetic valve V 5 and temperature sensors. The ECU takes a control over the vent-shut valve V 4 , the purge regulating electromagnetic valve V 5 and other parts and gives an instruction to have the pipes in the fuel tank system A down to a negative pressure, have the canister body 61 purged and transport the fuel vapor adsorbed in the canister body 61 to the intake manifold 15 .
Work of Drain Pipe
[0063] How the drain pipe D of the canister system 6 of the present invention works is to be explained with reference to FIG. 1 to FIG. 3 .
[0064] To begin with, it is explained how the drain pipe D of the canister system 6 when the fuel tank T is replenished, with reference to FIG. 1 and FIG. 2 .
[0065] For instance, when the fuel tank T is replenished after the engine E is switched off, fuel is poured into the fuel tank T from the fuel replenishment inlet 3 a through the filler pipe 3 . During this replenishment is transported into the canister system 6 through the vent pipe 14 fuel vapor remaining in the upper portion of the fuel tank T, whose volume amount is almost the same as the volume amount of the poured fuel into the fuel tank T. As a result the fuel replenishment is done smoothly.
[0066] Since part of the fuel vapor remaining in the upper portion of the fuel tank T is transported through the vapor return tube 4 and the vicinity of the replenishment inlet 3 a to the filler pipe 3 , the air from the atmosphere is inhibited from coming into the fuel tank T and it is possible to reduce the amount of the fuel vapor to be evaporated.
[0067] The fuel vapor coming from fuel tank T into the canister system 6 through the vent pipe 14 is adsorbed on the absorbent and stored. The air, from which the fuel vapor is removed, is discharged under the passenger room floor into the atmosphere out of the exhaust pipe D 2 and does not flow inside the passenger room.
[0068] The canister body 61 is installed adjacent to the fuel tank T and connected with the vent pipe 14 which is so short and thick that air easily flows from the fuel tank T to the canister body 61 because of small air flow resistance in-between.
[0069] The fuel vapor flowing into the vapor return tube 4 flows toward the replenishment inlet 3 a and circulates through the filler pipe 3 into the fuel tank T. As a result, an amount of air coming into the fuel tank T decreases, which results in reduction in an amount of fuel vapor generated.
[0070] Replenishment of the fuel tank T stops as soon as float valves not shown which are installed in the vapor return valve 5 and the replenishment float 7 are closed due to the fuel level becoming high, which leads to the replenishment gun not shown working.
[0071] Referring to FIG. 1 , how the drain pipe of the present invention works while the canister system 6 being purged is explained.
[0072] When the canister body 61 is purged while the engine E is in operation, the purge regulating electromagnetic valve V 5 is opened and fuel vapor adsorbed in the canister body 61 is transported into the intake manifold 15 of the engine E.
[0073] Specifically speaking, when the purge regulating electro-magnetic valve V 5 is opened, air is suctioned from the atmosphere through the exhaust pipe D 2 and fuel vapor adsorbed on the adsorbent in the canister body 61 is suctioned into the intake manifold 15 through the connection pipe D 1 , the vent shut valve V 4 , the canister body 61 , the purge pipe 19 and the purge regulating electromagnetic valve V 5 .
[0074] As a result the canister system 6 recovers its adsorbing capacity as fuel vapor adsorbed on the adsorbent is freed.
[0075] Since the drain filter 62 is installed at the highest position in the drain pipe D, water drops, dirt and dust are prevented from coming into the canister body 61 and the drain filter 62 is not clogged.
[0076] The branch pipe installed between the drain filter 62 and the auxiliary pipe D 3 has a double pipe structure in which a small diameter concentric pipe D 5 is disposed in a large diameter concentric D 6 and there is a space between the small diameter concentric pipe D 5 and the large diameter concentric pipe D 6 . Therefore an amount of air coming into and from the auxiliary pipe is restricted according to the flow resistance of the exhaust pipe D 2 . In case the exhaust pipe D 2 is clogged with dirt, the canister body 61 remains communicated with the atmosphere through the auxiliary pipe D 3 .
[0077] The present invention does not have to be restricted in the embodiment above mentioned. Other modifications are also possible as long as they are within the scope of the present invention.
[0078] For instance the drain filter 62 is described to be disposed at highest position in the drain pipe D, however the drain filter 62 does not have to be at the highest position and is disposed at a relatively high position in the drain pipe D, the same effect as is already mentioned is obtained. | In order to discharge air cleaned free from evaporated fuel vapor in a canister installed under the front seat floor, have none of the air coming inside a passenger room and inhibit water, dirt and dust from being absorbed in a drain pipe in a canister, the following drain pipe in a canister is invented. The drain pipe in canister is connected with a canister body installed under a front seat floor of a vehicle. The drain pipe in the canister comprises a first part extending from the canister body up to an upper portion of an engine room disposed on a front side of a passenger room, and a second part extending from the first part to a portion under a floor of the passenger room. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of application Ser. No. 09/800,158 filed Mar. 6, 2001 in the names of Kenneth A. Parulski et al.
FIELD OF THE INVENTION
[0002] The present invention relates to digital cameras and associated printers for producing hardcopy images captured by such cameras.
BACKGROUND OF THE INVENTION
[0003] Typically, images captured by digital cameras must be processed before they are printed. This processing is carried out in the printer. Significant computing and memory resources are required to process an image for printing. Accordingly, the printer must be provided with expensive computing and memory resources. One solution known in the prior art is to provide access to a stand-alone computer that is connectable to both the camera and the printer, either directly or by portable memory. This solution is inappropriate when the printer is to be used in remote locations distanced from the computer.
SUMMARY OF THE INVENTION
[0004] According to a feature of the present invention, we have come to appreciate that computing and memory resources, which already exist in electronic cameras in order for the camera to capture, process, compress, and store images, can be used to provide the computing and memory resources that are required to process an image for printing, particularly for printing on a portable, low cost ink jet printer.
[0005] It is an object of the present invention to provide a system wherein already-existing computing and memory resources in an electronic camera are used to process an image for printing. This is possible because the existing computing and memory resources are otherwise generally idle during the printing stage. Accordingly, it is a feature of the present invention that, rather than duplicating, in printers, computing and memory resources that are already in digital cameras, the present invention provides for camera and printer systems wherein significant computing and memory resources need exist only in the camera. Because such resources are already required by the camera in order to perform the camera functions, the cost of the camera is not increased. Because the resources are no longer required in the printer, the overall system cost is greatly reduced.
[0006] It is another object of the present invention to provide a digital camera that can support many different printers, each with its own set of parameters such as, for example, print size, pixel size, colorimetry, sensitometry, and artifacts compensation. Accordingly, it is a feature of the present invention to provide for uploading print drivers and printer parameters to the camera to provide a basis for image processing specific to an associated printer; whereby compensation may be done for variations in the printer characteristics which may occur as a result of printer manufacturing variations, and further so that compensation may be done for different media types which may be installed in the printer, in particular different types of ink jet media installed in an ink jet printer.
[0007] According to another feature of the present invention, a digital imaging system is provided that includes a digital camera and a color printer. The digital camera comprises: a housing; an image sensor adapted to capture analog image data; an analog-to-digital converter adapted to convert the analog image data captured by the image sensor to digital image data; an image processor adapted to perform first processing and compression of the digital image data to create a first-processed digital image file; digital memory in the camera housing, a plurality of first-processed digital image files from the image processor being stored in the digital memory; and a color printer interface to which a digital image file, which is selected from the digital memory, is applied. The color printer comprises: a color marking apparatus, and a digital camera interface, wherein the image processor in the digital camera is adapted to perform second processing on the selected digital image file before the selected digital image file is applied to the color printer interface.
[0008] According to a preferred embodiment of the present invention, color records of the user-selected digital image file are converted to multi-tone values during the second processing.
[0009] According to another preferred embodiment of the present invention, color records of the user-selected digital image file are processed during the second processing to provide ink limiting. The ink limiting is effected using type of printer, ink, and receiver media information provided by the separate color printer over the interface.
[0010] According to another preferred embodiment of the present invention, the separate color printer uses four ink colors, and the color records of the user-selected digital image file are converted to three image planes and are color corrected during said second processing to provide a set of color planes corresponding to each ink color of the separate color printer.
[0011] According to another preferred embodiment of the present invention, a color image display provides user-observable images of first-processed digital image files stored in the removable digital memory. User controls are coupled to the processor for user-selecting a digital image file to be second processed by the image processor.
[0012] According to another preferred embodiment of the present invention, the first processing includes: interpolation to provide red, green and blue image data values to provide red, green, and blue color planes; color correction of the red, green, and blue color planes; and image compression. The second processing includes decompression of the user-selected digital image file before the user-selected digital image file is applied to the interface.
[0013] The invention, and its objects and advantages, will become more apparent in the detailed description of the preferred embodiments presented below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic block diagram of a digital camera according to the present invention;
[0015] FIG. 2 is a schematic block diagram of a digital printer according to the present invention;
[0016] FIG. 3 is a schematic block diagram of a camera-printer system according to another embodiment of the present invention;
[0017] FIG. 4 is a detailed block diagram of a digital camera according to the present invention;
[0018] FIG. 5 is a flow diagram depicting the camera-related image processing operations provided by the digital camera of FIG. 3 in the process of capturing and storing images; and
[0019] FIG. 6 is a flow diagram depicting the printer-related image processing provided by the digital camera of FIG. 3 in the process of reading and printing images.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The present description will be directed in particular to elements forming part of, or cooperating more directly with, apparatus in accordance with the present invention. It is to be understood that elements not specifically shown or described may take various forms well known to those skilled in the art.
[0021] Referring to FIG. 1 , a digital camera 10 provides significant image processing and memory resources to capture, process, compress, and store images. An imager 12 includes an array of image sensors such as, for example, light sensitive photoelements. Conventionally, a complete image frame is available in digital form from imager 12 , only for a short time interval. Thus, the captured image is temporarily stored in raw form in a volatile memory 14 . Various image processing algorithms are stored in a program memory 16 , and are executed by an image processor 18 in order to process the image data stored in volatile memory 14 . For example, the image processing algorithms may include all or some of the processes of image sensor tone scale compensation, color filter array interpolation, color space transformation, re-sizing, spatial filtering, and compression, as will be described in greater detail later in reference to FIG. 5 . The resulting processed image data is then typically stored in a nonvolatile memory 20 .
[0022] This stored image must be further processed prior to printing. Such further processing may include some or all of the steps of decompression, color space transformation into color planes that coincide with the process colors of the particular printer, re-sizing, rotation, and compensation for the printing process, as will be described in greater detail later in reference to FIG. 6 . In prior art systems, this further processing has been effected by computing and memory resources in the printer or in a stand-alone computer. According to the present invention, this further processing is performed using the resources which are already in camera 10 . It is advantageous to perform all of the processing using the resources in camera 10 in order to avoid the additional expense of including similar resources in the printer. To effect such image processing in camera 10 , the camera is provided with a parameter memory 22 and a printer interface 24 , both to be further described hereinafter.
[0023] Referring to FIG. 2 , a printer 30 includes a camera interface 32 , an inexpensive simple processor 34 , a media transport mechanism 36 , an image memory 38 , a program memory 40 , and a marking apparatus 42 . A processed image, received from camera 10 of FIG. 1 via interface 32 , may be stored by printer 30 in image memory 38 for subsequent printing by marking means 42 under the control of simple processor 34 and a program stored in program memory 40 , or the processed image may be printed immediately. Simple processor 34 need not be capable of executing printer compensation algorithms.
[0024] Parameters, which may vary as a result of manufacturing variations in the printer, may be measured by an external means 44 at the time of manufacture. The parameters may then be stored in a variable parameter table 46 , which is part of the printer. Camera 10 may query printer 30 to establish whether the printer will perform compensation for the variable parameters, or whether the camera should request and accept the variable parameters from the printer, and subsequently perform compensation for said variable parameters. The printer provides both fixed parameters from a fixed parameter table 48 and variable parameters from its variable parameter table 46 to the camera by means of camera and printer interfaces 24 and 32 , respectively. The camera stores these parameters in local parameter memory 22 .
[0025] When an image in either volatile memory 14 or nonvolatile memory 20 is selected for printing, image processor 18 processes the selected image, using the fixed and variable parameters which are stored in parameter memory 22 , and transmits the processed image to the printer by means of interfaces 24 and 32 . Processing may include all or part of the operations of image sensor tone scale compensation, color filter array interpolation, decompression, color space transformation, re-sizing, rotation, cropping, spatial filtering, and compensation for the printing process, but is not limited to these specific operations.
[0026] In addition, parameters which can vary during printing may also be transmitted by the printer to the camera during the printing process and used by image processor 18 to further compensate the image for printing process variations during the printing operation. The parameters may include temperature, ink viscosity, measured density, and any other parameters which are known to vary with the specific printing process employed by the printer.
[0027] Further, parameters characteristic of particular media material at media transport mechanism 36 may be determined by simple processor 34 over an interface 50 and transmitted to the camera. The media parameters may include parameters which vary with media type and parameters which vary between different batches of media due to manufacturing variations. Thus, compensation for the media parameters may be done by image processor 18 in the camera.
[0028] Any such media parameters, fixed parameters, and variable parameters may be transferred from printer 30 to camera 10 by means of a removable non-volatile memory cartridge 52 shown in FIG. 3 . The memory cartridge may also be used to transfer images between the camera and the printer. As used herein, the phrases “camera interface and printer interface” are intended to include cable connections, transferable memory, radiation transmission (light, microwave, infrared, etc.), and other forms of information transfer between components.
[0029] FIG. 4 is a block diagram showing portable digital camera 10 depicted in more detail than was shown in FIG. 1 . Digital camera 10 stores images on a removable flash memory card 330 , which is a specific type of non-volatile memory 14 (shown in FIG. 1 ). Digital camera 10 includes a zoom lens 312 having zoom and focus motor drives 310 and an adjustable aperture and shutter (not shown). Zoom lens 312 focuses light from a scene (not shown) on image sensor 12 . Image sensor 12 may be, for example, a single-chip color CCD image sensor, such as a Toshiba model TCD5603D CCD sensor, available from Toshiba America Electronic Components, Irvine, Calif., U.S.A. The model TCD5603D sensor has approximately 1536 columns and 1024 rows of photoelements, and uses the well-known Bayer color filter pattern. Other CCD or CMOS image sensors, having various image array sizes and color filter patterns, may alternatively be used.
[0030] Image sensor 12 is controlled by clock drivers 306 . Zoom and focus motors 310 and clock drivers 306 are controlled by control signals supplied by a control processor and timing generator circuit 304 . The control processor and timing generator 304 receives inputs from autofocus and autoexposure detectors 308 and controls a flash 302 . The analog output signal from image sensor 12 is amplified and converted to digital data by the analog signal processing (ASP) and analog-to-digital (A/D) converter circuit 316 . The A/D converter may alternatively be included a part of image sensor 12 , particularly if a CMOS image sensor is used. The digital data is stored in a DRAM buffer memory 318 , which is a specific type of volatile memory 14 (shown in FIG. 1 ). The digital image data stored in DRAM buffer memory 318 is subsequently processed by a processor 18 controlled by the firmware stored in program memory 16 , which can be provided by a flash EPROM memory 328 . Flash EPROM memory 328 can be a single memory chip which can also provide parameter memory 22 .
[0031] The processed digital image file is provided to a memory card interface 324 which stores the digital image file on removable memory card 330 . Removable memory cards are known to those skilled in the art. For example, removable memory card 330 may be adapted to the Compact Flash interface standard, such as described in the CompactFlash Specification Version 1.3, published Aug. 5, 1998 by the CompactFlash Association, Palo Alto, Calif., U.S.A. Alternatively, removable memory card 330 can be adapted to the PCMCIA card interface standard, as described in the PC Card Standard, Release 2.0, published September 1991 by the Personal Computer Memory Card International Association, Sunnyvale, Calif., U.S.A. Removable memory card 330 can also be adapted to the well known secure digital (SD), solid state floppy disk card (SSFDC) or Memory Stick formats. Other types of non-volatile digital memory devices, such as magnetic hard drives, magnetic tape, or optical disks, could alternatively be used to store the digital images.
[0032] Processor 18 performs color interpolation followed by color and tone correction, in order to produce rendered sRGB image data as defined in IEC 61966-2-1 Multimedia systems and equipment—Color measurement and management—Part 2-1: Color management—Default RGB color space—sRGB available from the International Electrotechnical Commission, Geneva, Switzerland. The rendered sRGB image data is then JPEG compressed and stored as a JPEG image file on removable memory card 330 using an JPEG/Exif version 2.1 image file as defined in Digital Still Camera Image File Format Standard (Exchangeable Image File Format for Digital Still Camera: Exif), version 2.1, JEIDA-49-1998 available from the Japan Electronic Industry Development Association, Tokyo, Japan. The JPEG/Exif image files can be utilized by many different image capable devices, such as computers and imaging kiosks.
[0033] Processor 18 also creates a “thumbnail” size image that is stored in RAM memory 326 and supplied to color LCD image display 332 , which displays the captured image for the user to review. Electronic camera 300 is controlled by user controls 303 , such as a series of user buttons including a shutter release (e.g., capture button) (not shown) which initiates a picture taking operation. The graphical user interface displayed on color LCD image display 332 is controlled by the user interface portion of the firmware stored in program memory 16 . The graphical user interface is also used to select images for printing, and can optionally be used to select the number of copies and the print layout (e.g. the number images printed on one page). The images selected for printing may be immediately printed, if digital camera 10 is connected to printer 30 . If not, image processor 18 creates an “image utilization” file listing the image to be printed, the number copies for each image, and the print size, as described in commonly assigned U.S. patent application Ser. No. 08/977,382, filed by Parulski on Nov. 24, 1997, the disclosure of which is herein incorporated by reference. This “image utilization” file, which can conform to the well-known digital print order format (DPOF) is stored on removable flash memory card 330 along with the digital images captured by digital camera 10 .
[0034] FIG. 5 is a flow diagram depicting the image processing operations that are performed by image processor 18 in digital camera 10 in order to process the images from image sensor 12 stored in DRAM buffer memory 318 .
[0035] The Bayer pattern color filter array data (block 500 ) which has been digitally converted by A/D converter 16 is interpolated in block 510 to provide red, green and blue (RGB) image data values at each pixel location in order to provide complete RGB color planes. Color filter array interpolation in block 510 can use the luminance CFA interpolation method described in commonly assigned U.S. Pat. No. 5,652,621, entitled “Adaptive color plane interpolation in single sensor color electronic camera” to Adams et al., the disclosure of which is herein incorporated by reference. The color filter array interpolation in block 510 can also use the chrominance CFA interpolation method described in commonly assigned U.S. Patent No. 4 , 642 , 678 , entitled “Signal processing method and apparatus for producing interpolated chrominance values in a sampled color image signal”, to Cok, the disclosure of which is herein incorporated by reference.
[0036] A color space transformation is applied to the interpolated RGB color planes in order to provide color correction, prior to image storage. The RGB color planes are color corrected in block 520 using, for example, the 3×3 linear space color correction matrix 20 depicted in FIG. 4 of commonly assigned U.S. Pat. No. 5,189,511, entitled “Method and apparatus for improving the color rendition of hardcopy images from electronic cameras” to Parulski et al., the disclosure of which is incorporated herein by reference. The color correction matrix coefficients which are stored in program memory 16 in digital camera 10 can be, for example:
Rout=1.50 Rin−0.30 Gin−0.20 Bin
Gout=−0.40 Rin+1.80 Gin−0.40 Bin
Bout=−0.20 Rin−0.20 Gin+1.40 Bin
[0037] The color corrected color planes are tone corrected in block 530 . This tone correction 530 can use, for example, the lookup table corresponding to FIG. 2 of U.S. Pat. No. 5,189,511 cited above. This lookup table is stored in program memory 16 in digital camera 10 . Alternatively, color correction image processing operations 520 and tone correction image processing operations 530 can be provided by a three-dimensional lookup table (3D LUT). An example of such a 3D LUT is described in commonly assigned U.S. patent application Ser. No. 09/540,807 filed Mar. 31, 2000 in the names of Geoffrey Woo et al., the disclosure of which is incorporated herein by reference. The 3D LUT is more complex than the 3×3 matrix and single-channel LUT approach described above. However, it allows better control of color saturation. For example, it allows increased color saturation for most memory colors without increasing the saturation of flesh tone colors and near-neutral colors.
[0038] The image sharpening provided in block 540 of FIG. 5 can utilize the method described in commonly assigned U.S. Pat. No. 4,962,419 ('419 patent), entitled “Detail processing method and apparatus providing uniform processing of horizontal and vertical detail components” to Hibbard et al., the disclosure of which is incorporated herein by reference.
[0039] The image compression provided in block 550 of FIG. 6 can use the method described in commonly assigned U.S. Pat. No. 4,774,574 (the '574 patent), entitled “Adaptive block transform image coding method and apparatus” to Daly et al., the disclosure of which is incorporated herein by reference.
[0040] The compressed image files are stored on removable flash memory card 330 as Exif image files. After a series of images have been taken and stored on removable memory card 330 , removable memory card 330 can optionally be inserted into a memory card reader in the user's host computer (not shown) in order to transfer the images captured by the digital camera to the host computer, where they can be viewed, e-mailed via the Internet, etc. To print images without using a host computer, an interface cable 342 can be used to connect between printer interface 24 in digital camera 10 and the corresponding camera interface in digital printer 30 . Printer interface 24 may conform to, for example, the well-know universal serial bus (USB) interface specification. Alternatively, printer interface 24 may conform to the RS-232 interface specification, the IEEE 1394 (Firewire) interface specification, or other cable interface specifications. Alternatively, the interface may utilize a wireless interface such as the well-known IrDA (Infrared Data Association) interface or an RF (radio frequency) interface such as the well-known Bluetooth RF interface.
[0041] FIG. 6 is a flow diagram depicting the printer-related image processing provided by image processor 18 in digital camera 10 in the process of reading and printing images on an ink jet printer. The images to be printed are selected by the user as described earlier. In block 600 , the image file to be printed is retrieved from non-volatile memory 20 in FIG. 1 , such as removable flash memory card 330 in FIG. 4 . If digital camera 10 compressed images prior to storage, for example by creating the JPEG/Exif image files described earlier, the image file is decompressed in block 605 to provide red, green and blue (RGB) color planes. In block 610 , each decompressed RGB color plane is sharpened in order to compensate for the sharpness degradation of the ink jet printing process. A preferred sharpening algorithm uses the well-known unsharp masking technique to produce a sharpened color plane Xs by creating a blurred version Xb of the original decompressed color plane Xo, and then computing:
Xs= 1 +k ( Xo−Xb )
where X is each of the R, G, and B color planes, and k is a gain factor. Gain factor k can be a parameter stored in fixed parameter table 48 in printer 30 for all printers of a given model, or alternately in variable parameter table 46 for a particular printer, which is measured for each batch of printers as they are manufactured. The gain factor is provided from printer 30 to digital camera 10 by means of camera and printer interfaces 24 and 32 respectively, when printer 30 is connected to camera 10 . The camera stores the gain factor k in camera parameter memory 22 .
[0042] The sharpened RGB color planes are color corrected in block 615 . The color correction block preferably uses a 3D LUT. The input to the 3D LUT is the RGB color plane, and the output is, for example, cyan, magenta, yellow, and black (CMYK) color planes corresponding to the color inks used as the process colors for printer 30 . This 3D LUT is preferably provided using the ICC profile format defined by the International Color Consortium. The 3D LUT profile values can be parameters stored in fixed parameter table 48 in printer 30 for all printers of a given model, or alternately in variable parameter table 46 for a particular printer, which is measured for each batch of printers as they are manufactured. The ICC profile is provided from printer 30 to digital camera 10 by means of camera and printer interfaces 24 and 32 respectively, when printer 30 is connected to camera 10 . The camera stores the ICC profile values in camera parameter memory 22 .
[0043] If printer 30 is an ink jet printer using more than four color inks, the CMYK color planes are further processed in block 615 to provide color planes corresponding to each ink. This processing preferably uses ink rendering processing to convert a single color plane (e.g. the cyan channel C) into two color planes (e.g. light cyan Cl and dark cyan Cd). Therefore, the output of color correction block 615 is set of color planes corresponding to the color inks used in the inkjet printer, which may for example use light cyan, dark cyan, light magenta, dark magenta, yellow, and black color inks as the process colors.
[0044] In block 620 , the color records are calibrated in order to correct for variations in tone scale. These variations may be may be the result of manufacturing variations in printer 10 or media (e.g. ink jet head or paper receiver) used by the printer. The calibration is provided by a one-dimensional lookup table applied to each color plane. The lookup table can be provided by parameters stored in variable parameter table 46 for a particular printer, which is measured for printer 30 as it is manufactured. Alternatively, the lookup table can be created by image processor 18 in digital camera 10 using parameters or settings provided by printer 30 . The parameters or settings can include, for example, data indicating the type of media (e.g. ink jet head or paper receiver) used by the printer, or data such as the ink viscosity, humidity, etc. The lookup tables, parameters, or settings are provided from printer 30 to digital camera 10 by means of camera and printer interfaces 24 and 32 respectively, when printer 30 is connected to camera 10 . The camera stores this data in camera parameter memory 22 .
[0045] In block 625 , the calibrated color planes corresponding to the inks of the ink jet printer are processed to provide ink limiting. This processing reduces the amount of ink that is deposited on the receiver media in high ink laydown areas. This is required in order to minimize deglossing and ink bleeding problems that reduce the image quality. It also reduces the stickiness, long drying time and delamination problems caused by laying down too much ink. The ink limiting step typically limits the total ink provided by all ink color planes to a maximum of 2 to 3 times the maximum amount of ink provided by a single color plane. The exact limit depends on the combination of the printer, ink, receiver media, and, to some extent, the humidity. To determine the appropriate limit to make a print, the type of printer, ink, and receiver media can be communicated from printer 30 to digital camera 10 . In some embodiments, a humidity sensor in printer 30 can be used to sense the approximate humidity. A corresponding humidity parameter can be communicated, along with the type of printer, ink, and receiver media, from printer 30 to digital camera 10 by means of camera and printer interfaces 24 and 32 respectively, when printer 30 is connected to camera 10 . The camera stores this data in camera parameter memory 22 .
[0046] In block 630 , the color records corresponding to the process colors of the ink jet printer are resized and rotated if necessary. This converts the pixels captured by the digital camera (e.g. the 1536 columns×1024 rows) to the appropriate number of pixels required by printer 30 in order to produce a selected image size. To perform this conversion, the number of pixels per inch used by printer 30 is communicated to digital camera 10 , when printer 30 is connected to camera 10 . The camera stores this data in camera parameter memory 22 .
[0047] In block 635 , the color records are converted to multi-tone values. Multi-toning is the process of reducing the bit depth of the image in a manner that reduces the spatial resolution while increasing the density resolution. Multi-toning is required in ink jet printers because the ink jet printers have few density levels (e.g. two density levels corresponding to ink or no ink, or four density levels corresponding to various ink drop sizes). Multi-toning using two density levels is also known as half-toning. Multi-toning may be provided using a variety of algorithms, such as the well-known “error diffusion” and “blue noise dithering” algorithms. In order for image processor 18 in digital camera 10 to provide multi-toning appropriate for printer 30 , the number of density levels, and the density of each level, is provided by printer 30 . More specifically, the density levels for each multi-tone level are stored in fixed parameter table 48 in printer 30 for all printers of a given model. The density levels are provided from printer 30 to digital camera 10 by means of camera and printer interfaces 24 and 32 respectively, when printer 30 is connected to camera 10 . The camera stores the density levels in camera parameter memory 22 .
[0048] In step 650 , the multi-tone color records corresponding to the inks used in printer 30 are communicated from digital camera 10 to printer 30 by means of camera and printer interfaces 24 and 32 respectively. Printer 30 produces an ink jet print using the multi-tone color records by controlling the marking apparatus 42 and media transport mechanism 36 using simple processor 34 .
[0049] In an alternative embodiment, some or all of the printer parameters are provided on a removable media, such as a floppy disk (not shown) or removable flash memory card 330 , rather than being stored in fixed parameter table 48 or variable parameter table 46 . The removable media is provided along with printer 30 , and is inserted into digital camera 10 so that the parameters can be downloaded and stored in parameter memory 22 . In the case of a floppy disk, the disk may be inserted into a separate host computer (not shown) and downloaded to the camera using a computer interface. The computer interface can use the same type of connection (e.g. USB, RS-232, IEEE 1394) as printer interface 24 . Alternatively, the parameters may be included as part of a printer driver which performs all of the processing described in relation to FIG. 6 . In this case, the printer driver firmware is downloaded from the removable media (supplied along with printer 30 ) and stored in the program memory 16 of digital camera 10 .
[0050] In another alternative embodiment, some or all of the printer parameters, such as an ICC profile appropriate for particular “printer consumables” sold as a package, are provided as part of the printer consumables package. The printer consumables package can include, for example, printer receiver media (e.g. a quantity of photo grade ink jet paper) and a replacement color ink jet head for a particular type of printer. This printer consumables package can be provided with a nonvolatile digital memory, such as an EPROM, provided as part of the replacement color ink jet head. The parameters, such as the ICC profile, can be read from the EPROM memory by the simple processor 34 via the interface to the marking apparatus 42 when the color ink jet head is inserted into the printer 30 , and transferred to the digital camera 10 via the interface 32 .
[0051] The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. | A digital imaging system is provided that includes a digital camera and a color printer. The digital camera comprises: a housing; an image sensor adapted to capture analog image data; an analog-to-digital converter adapted to convert the analog image data; an image processor adapted to perform first processing and compression of the digital image data to create a first-processed digital image file; a digital memory in the camera housing having a plurality of the first-processed digital image files stored in the digital memory; and a color printer interface to which a digital image file, which is selected from the digital memory, is applied. The color printer comprises: a color-marking apparatus, and a digital camera interface, wherein the image processor in the digital camera is adapted to perform second processing on the selected digital image file before the selected digital image file is applied. | 7 |
TECHNICAL FIELD
The invention relates to detection of protozoan parasites, particularly Neospora and Toxoplasma species using polymerase chain reaction (PCR) techniques and in particular to the detection of Neospora caninum and Toxoplasma gondii in clinical and veterinary samples.
BACKGROUND OF THE INVENTION
Neospora caninum and Toxoplasma gondii are closely related protozoan parasites responsible for disease in a wide range of animals. N. caninum has recently been recognised as an important cause of neuromuscular disease in dogs, and as a cause of abortion and neonatal mortality in cattle and other domestic animals. T. gondii is a common cause of ovine abortion, and is one of the most important opportunistic pathogens in immunosuppressed human patients, such as those with acquired immune deficiency syndrome. Effective management of neosporosis and toxoplasmosis requires prompt diagnosis and treatment. The development of a range of efficient diagnostic tests is therefore essential.
Diagnosis of neosporosis and toxoplasmosis is difficult due to the vague nature of early clinical signs and the low numbers of parasites present in infected tissues. In the past, neosporosis was misdiagnosed as toxoplasmosis because of the similarities in clinical signs and pathological changes associated with infection with each organism. While serological and immunohistochemical techniques may aid diagnosis, clinically normal animals may have antibody titres suggestive of disease, and interpretation of immunohistochemistry is sometimes difficult due to variable staining and cross-reactivity. Molecular biological techniques such as the polymerase chain reaction (PCR) offer a highly sensitive and specific alternative to immunologic approaches to diagnosis. Previously developed PCR protocols for N. caninum and T. gondii, however, have not fully exploited the potential of this technique.
The PCR protocols developed by the present inventors utilize primers which hybridise within the internal transcribed saucer 1 (ITS1) region of the ribosomal RNA (rRNA) gene Unit of N. caninum and T. gondii (Payne and Ellis, 1990). The ITS1 region of the rRNA gene unit is relatively variable but also contains conserved regions consistent with its role in processing the rRNA molecule. Both the ribosomal RNA and the transcribed spacer regions have significant secondary structure due to their rule in protein translation and in the processing of the rRNA molecules respectively.
In the absence of a species-specific gene, the ITS1 region maybe a target for diagnostic PCR, as it is present at high copy number and exhibits high inter-species variability, while being generally conserved within a species Payne and Ellis, 1996). Furthermore, the ITS1 is readily sequenced and characterized because it is flanked by the 18S and 5.8S rRNA genes. The ITS1 regions of N. caninum and T. gondii are 421 and 392 bp, respectively, and the similarity between the two species is 82% (Payne and Ellis, 1996). Guay and co-workers (1993) estimated there to be around 110 copies of the ribosomal RNA gene unit in each T. gondii genome.
High sensitivities have been reported for PCR protocols targeting the ribosomal RNA gene unit, due to the high gene copy number. Guay and co-workers (1993) described a PCR capable of detecting a single organism using primers specific for the ITS1 region of T. gondii. Holmdahl and Mattson (1995) and Payne and Ellis (1996) recently remand PCR protocols for the detection of N. caninum with was capable of detecting five and seven organisms respectively. While these tests were specific for N. caninum, the sensitivity of the techniques is inadequate for diagnostic PCR because organisms may be present in tissues only in very low numbers and target DNA in some clinical samples may be degraded.
The present inventors have developed a sensitive PCR test for protozoan parasites that is particularly suitable for use in the detection of these microorganisms in clinical and biological samples.
SUMMARY OF THE INVENTION
In a first aspect, the present invention consists in a method of detecting a protozoan parasite in a sample containing the parasite, the method comprising the steps of:
(a) adding to the sample a pair of flanking oligonucleotide primers, at least one flanking primer being specific for and each being complementary to an opposite strand of a double stranded DNA molecule encoding the ITS1 of the protozoan parasite and flanking a region of the ITS1;
(b) further adding to the sample a pair of nested oligonucleotide primers, each nested primer being specific for and complementary to an opposite strand of the DNA encoding the ITS1 of the protozoan parasite, the nested primers being complementary to the region of the ITS1 spanned by the flanking primers;
(c) providing buffers, reagents, nucleotides and a thermostable DNA polymerase to the sample to form a reaction mixture;
(d) heating the sample to a temperature such that the double stranded DNA encoding the ITS1 of the protozoan parasite denatures to form single stranded DNA molecules;
(e) cooling the denatured sample to a temperature such that only the flanking primers anneal to their respective complementary sequences on the denatured DNA molecules;
(f) heating the denatured and annealed sample to a temperature such that the DNA polymerase extends the primers to form new double stranded DNA molecules spanning the region of the ITS1 defined by the flanking primers;
(g) repeating steps (d), (e) and (f) such that the number of copies of the region of DNA encoding the ITS1 region is amplified;
(h) heating the sample to a temperature such that the newly amplified double stranded DNA encoding the ITS1 region denatures to form single stranded DNA molecules;
(i) cooling the denatured sample to a temperature such that only the nested primers anneal to their respective complementary sequences on the denatured DNA;
(j) heating the denatured and annealed sample to a temperature such that the DNA polymerase extends the primers to form new double stranded DNA molecules spanning the region of the ITS1 defined by the nested primers;
(k) repeating steps (h), (i) and (j)) such that the number of copies of the region of DNA is amplified; and
(l) detecting the amplified DNA.
The sample can be any sample including fixed or frozen tissue samples, and any biological fluid including semen, sputum, blood, saliva, cerebrospinal spinal fluid, cord blood and other excretion. Usually the sample is pre-treated to extract or concentrate the nucleic acid material from the sample by standard methods known to the art. Preferably, the method is carried out in one reaction vessel.
In a preferred embodiment of the present invention the protozoan parasite is a Neospora spp or a Toxoplasma spp. More preferably the Neospora spp is N. caninum and the Toxoplasma spp is T. gondii.
Preferably, in the method for detection of N. caninum the flanking oligonucleotide primers include SEQ ID NO:5 (forward) and SEQ ID NO:9 (reverse) and the nested oligonucleotide primers include SEQ ID NO:6 or SEQ ID NO:7 (forward) and SEQ ID NO:8 (reverse) or portions thereof. More preferably the primers are SEQ ID NO:5, SEQ ID NO:9, SEQ ID NO:6 or SEQ ID NO;7 and SEQ ID NO:8. Preferably, in the method for detection of T. gondii the flanking oligonucleotide primers include SEQ ID NO:1 (forward) and SEQ ID NO:9 (reverse) and the nested oligonucleotide primers include SEQ ID NO:3 (forward) and SEQ ID NO:4 (reverse) or portions thereof. More preferably the primers are SEQ ID NO:1, SEQ ID NO:9, SEQ ID NO:3 and a SEQ ID NO:4. It will be appreciated that the primers can be longer (or shorter) by the addition (or removal) of one or more bases at both or either ends.
In a preferred form of the present invention, one of the flanking primers is designed from an ITS1 sequence common to Neospora and Toxoplasma species and the other flanking primer is designed from an ITS1 sequence specific to the parasite to be detected. Most preferably, the primer common to Neospora and Toxoplasma species is the reverse primer SEQ ID NO:9.
The preferred primers for use in the present invention are defined below:
SEQ ID NO.1 CATTCACAGTCCTTATTCTTTA (TF1)
SEQ ID NO:2 CGCTGCTTCCAATATTG (TS3)
SEQ ID NO:3 TCCATTGGAGAGATTTG (TS4)
SEQ ID NO:4 AAACTCCTGGAAATCAGTA (TR1)
SEQ ID NO:5 GCGTGATATACTACTCCCTGT (NF1)
SEQ ID NO:6 GCTGATAATGAAAGTGTG (NS1)
SEQ ID NO:7 CATGTGGATATTTTGCA (NS2)
SEQ ID NO:8 AAACTCCTGGAAGTTAAAG (NR1)
SEQ ID NO:9 AAATAACGGTGTGGGAAAA (SR1)
In order to assist in the performance of the present invention, a higher concentration of nested primers is used compared to the concentration of flanking primers. A ratio of 100 to 1 of nested primers verses flanking primers is preferably used so that both sets of primers can be added in step (c). Alternatively, the nested primers are added after the initial amplification in step (g).
The flanking and nested oligonucleotide primers define the region of the ITS1 of the protozoan parasite that is suitable for the present method and gives the method its specificity for the parasite to be detected. It will be appreciated that any nested primers that are specific for the DNA region defined by the flanking primers would be suitable. For the method to function correctly, the nested primers should have lower melting points from those of the flanking primers. This difference in melting points ensures that during step (g) only the newly amplified DNA from step (f) is amplified via the flanking primers.
The present inventors have found that a further reduction in the denaturation temperature after initial amplification prevents dissociation of the external product, resulting in selective annealing and extension of the nested primers in the later stages of amplification. Low concentrations of flanking primers and late entry of the nested primers into the amplification reaction may assist in the delay of formation of non-specific amplification products, allowing an increased number of thermal cycles and thus enhanced sensitivity. Amplification specificity is also enhanced, as any non-target sequences amplified by the flanking primers are extremely unlikely to support further amplification by the nested primers.
The reagents used in step (c) are standard reagents commonly used in PCR and are used at known concentrations. Preferably the DNA polymerase is Taq DNA polymerase.
The detection of the amplified DNA in step (l) can be by any means known to the art. Preferably, the DNA is detected by electrophoresis.
In a most preferred embodiment of the method to detect N. caninum using the flanking primers SEQ ID NO:5 (forward) SEQ ID NO:9 (reverse) and the nested primers are SEQ ID NO:7 (forward) and SEQ ID NO:8 (reverse), the temperatures and cycling times are as follows:
(g) 5 cycles of 94° C. for 30 seconds, 60° C. for 150 seconds, 72° C. for 30 seconds;
(g) 15 cycles of 88° C. for 30 seconds, 60° C. for 30 seconds, 72° C. for 30 seconds;
(k) 10 cycles of 88° C. for 30 seconds, 54° C. for 30 seconds, 72 °C. for 30 seconds;
(k) 20 cycles of 86° C. for 30 seconds, 54° C. for 30 seconds, 72° C. for 30 seconds.
In a most preferred embodiment of the method to detect T. gondii using the flanking primers SEQ ID NO:1 (forward) SEQ ID NO:9 (reverse) and the nested primers are SEQ ID NO:3 (forward) and SEQ ID NO:4 (reverse), the temperatures and cycling times are as follows:
(g) 5 cycles of 94° C. for 30 seconds, 60° C. for 150 seconds, 72° C. for 30 seconds;
(g) 15 cycles of 88° C. for 30 seconds, 60° C. for 30 seconds, 72° C. for 30 seconds;
(k) 10 cycles of 88° C. for 30 seconds, 54° C. for 30 seconds, 72° C. for 30 seconds;
(k) 20 cycles of 86° C. for 30 seconds, 54° C. for 30 seconds, 72° C. for 30 seconds.
The present inventors enhanced the sensitivity of a diagnostic PCR by subjecting the product of an initial PCR reaction to further amplification using internal, or "nested primers". Nested amplification was achieved in a single tube using "drop-in, drop-out" nested primers and a thermal profile which selectively extended the flanking primer pair, then the nested primer pair.
The optimised single tube nested PCR test of the present invention is sensitive to a single copy of target sequence and specific for the target microorgmaism. Its diagnostic utility was assessed using formalin-fixed tissues from dogs suspected of having neosporosis or toxoplasmosis.
In a second aspect, the present invention consists in the oligonucleotide primers SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4 and SEQ ID NO:9.
In a third aspect, the present invention consists in a method of amplifying Neospora caninum DNA by polymerase chain reaction (PCR) using a pair of oligonucleotide primers, one oligonucleotide primer being specific for and complimentary to the ITS1 of N. caninum, and the other primer being complimentary to an ITS1 sequence common to Neospora and Toxoplasma species.
Preferably, one primer includes the sequence SEQ ID NO:6 or SEQ ID NO:7 or portions thereof, and the other primer includes the sequence SEQ ID NO:9 or portion thereof. More preferably, the primers are SEQ ID NO:6 or SEQ ID NO:7 and SEQ ID NO:9 and the amplification utilises standard PCR methods. The method according to the third aspect of the present invention can be used to detect the presence of N. caninum in a sample by detecting the presence of the DNA amplified by the PCR test using the primers of the invention.
The amplified DNA product using the primers SEQ ID NO:6 and SEQ ID NO:9 comprises approximately 137 bp and the amplified DNA product using the primers SEQ ID NO:7 and SEQ ID NO:9 comprises approximately 182 bp. The amplified DNA products can be detected by standard methods known to the art.
In a fourth aspect, the present invention consists in a method of amplifying Toxoplasma gondii DNA by polymerase chain reaction (PCR) using a pair of oligonucleotide primers, one oligonucleotide primer being specific for and complimentary to the ITS1 of T. gondii, and the other primer being complimentary to an ITS1 sequence common to Neospora and Toxoplasma species.
Preferably, one primer includes the sequence SEQ ID NO:2 or SEQ ID NO:3 or portions thereof, and the other primer includes the sequence SEQ ID NO:9 or portion thereof. More preferably, the primers are SEQ ID NO:2 or SEQ ID NO:3 and SEQ ID NO:9 and the amplification utilises standard PCR methods. The method according to the fourth aspect of the present invention can be used to detect the presence of T. gondii in a sample by detecting the presence of the DNA amplified by the PCR test using the primers of the invention.
The amplified DNA product using the primers SEQ ID NO:2 and SEQ ID NO:9 comprises approximately 144 bp and the amplified DNA product using the primers SEQ ID NO:3 and SEQ ID NO:9 comprises approximately 221 bp. The amplified DNA products can be detected by standard methods known to the art.
It was found that the methods according to the third and fourth aspects of the present invention were not sensitive to detect the presence of low numbers of Neospora spp and Toxoplasma spp respectively, in biological samples including frozen and fixed tissue samples. The method according to the first aspect of the present invention was then developed by the present inventors and had the surprising advantage at being able to detect low numbers of organisms in such biological samples.
In order that the present invention may be more clearly understood preferred forms will be described with reference to the following examples and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the relative positions of PCR primers within the ITS1 region of N. caninum and T. gondii;
FIG. 2 is electrophoresis analysis showing specificity of N. caninum single tube nested PCR, Lane 1 N. caninum (NC-Liverpool isolate) DNA; Lane 2 N. caninum (NC-1 isolate) DNA; Lane 3 T. gondii (RH strain) DNA; Lane 4 T. gondii (ME-49) DNA: Lane 5 Sarcocystis cruzi DNA; Lane 6 Dog DNA; and Lane 7 Cow DNA;
FIG. 3 is electrophoresis analysis showing specificity of optimised N. caninum single tube nested PCR, Lane 1 100 fg N. caninum DNA; Lane 2 10 fg; Lane 3 1 fg; lane 4 reagent control (no DNA);
FIG. 4 shows amplification of N. caninum DNA from formalin-fixed, paraffin embedded tissue sections Lane 1, Negative control dog brain tissue+10 fg parasite N. caninum DNA; Lane 2, Brain tissue from dog infected with N. caninum; Lane 3, Brain tissue from aborted bovine foetus infected with Neospora spp; Lane 4, Brain tissue from dog infected with T. gondii, Lane 5, Negative control dog brain tissue section; Lane 6, Negative control brain cow issue section.
FIG. 5 shows amplification of T. gondii DNA from formalin-fixed, paraffin embedded tissue sections. Lane 1, Negative control dog brain tissue+10 fg T. gondii DNA; Lane 2, Brain tissue from dog infected with N. caninum; Lane 3, Brain tissue from aborted bovine foetus infected with Neospora spp; Lane 4, Brain tissue from dog infected with T. gondii, Lane 5, Negative control dog brain tissue section; Lane 6, Negative control brain cow tissue section.
DETAILED DESCRIPTION OF THE INVENTION
1. MATERIALS AND METHODS
1.1 DNA samples
Parasite genomic DNA used in the PCR was phenol chloroform extracted from cell culture-derived tachyzoites of N. caninum and T. gondii. Canine and bovine genomic DNA/Dog and cow genomic DNA/Genomic DNA from dog and cow (Promega, USA) were used as host animals controls.
1.2 Tissue sections
Formalin-fixed, paraffin embedded brain tissue sections from a dog and an aborted bovine foetus with naturally acquired neosporosis, and a dog with naturally acquired toxoplasmosis (all confirmed by immunohistochemistry and IFAT) were used as positive controls. Tissue sections from a dog and cow with no clinical signs of protozoal disease (which tested negative for both Neospora and T. gondii IFAT and immunohistochemistry) were used as negative controls.
Tissues from 10 dogs with clinical signs suggestive of neosporosis or toxoplasmosis were tested by PCR in parallel with immunohistochemistry. Sections from the brain and muscle of 10 healthy dogs were used as normal controls.
1.3 Reaction setup
All manipulations for PCR were performed in a Class II Biological Safety Cabinet dedicated to PCR. The precautions against contamination recommended by Dragon and co-workers (1994) were implemented. Amplifications were performed in 600 μl microfuge tubes (Trace Biosciences, Australia).
For each experiment, reagents for all reactions were prepared as a master mix containing all reagents except template DNA, to minimise labour, operator error and artefactual variation between reactions in optimisation experiments. Reagents were kept chilled on ice at all times, and one reagent (such as dNTPs or magnesium) was withheld until immediately before the master mix was added to sample DNA to minimise template independent polymerase activity. The reactions were overlaid with mineral oil to prevent evaporation, the tubes were capped and placed immediately in a thermal cycler (Hybaid Omnigene® thermal cycler, Hybaid, USA) preheated to 95° C. The thermal cycler program was then commenced.
Following thermal cycle, amplification products were refrigerated until electrophoretic analysis on 2% agarose gels.
1.4 Conventional PCR
The conventional 30 cycle PCR protocol developed in the inventors' laboratory utilised a forward primer specific for either N. caninum or T. gondii and a conserved reverse primer (SEQ ID NO:6, SEQ ID NO:2 or SEQ ID NO:3 and SEQ ID NO:9 respectively, see Table 1, FIG. 1). This protocol was used as a starting point in determining optimal reaction conditions for each new primer pair. Reaction conditions were as follows 1xPCR Buffer/0.2 mM each dNTP/50 μM each primer/0.5 units of Taq DNA polymerase in a total reaction volume of 50 μl. Tubes were overlaid with mineral oil and placed in a Hybaid Omnigene thermal cycler programmed for 95° C. for 5 minutes; 30 cycles of 94° C. for 30 seconds, 55° C. for 30 seconds, 72° C. for 30 seconds; and finally 72° C. for 10 minutes.
TABLE 1__________________________________________________________________________ MeltingPrimer PointID NO Sequence (5'-3') Specificity Direction Position (0° C.)__________________________________________________________________________1 CATTCACAGTCCTTATTCTTTA T. gondii Forward External 56.12 CGCTGCTTCCAATATTG T. gondii Forward3 TCCATTGGAGAGATTTG T. gondii Forward Nested 49.44 AAACTCCTGGAAATCAGTA T. gondii Reverse Nested 49.55 GCGTGATATACTACTCCCTGT N. caninum Forward External 56.56 GCTGATAATGAAAGTGTG N. caninum Forward Nested 48.07 CATGTGGATATTTTGCA N. caninum Forward Nested 48.68 AAACTCCTGGAAGTTAAAG N. caninum Reverse External 48.69 AAATAACGGTGTGGGAAAA conserved Reverse External 55.5__________________________________________________________________________
1.5 Single tube nested PCR
For single tube nested PCR, a new flanking forward and nested reverse primer specific for each N. caninum and T. gondii were designed to complement existing primers (see Table 1 and FIG. 1). As DNA in some clinical samples may be degraded due to aging or chemical fixation, flanking primers were selected so as to amplify as short a fragment as practical.
The flanking primers were designed so as to have a similar melting point to SEQ ID NO:9, and the nested primers a lower melting point, closer to that of SEQ ID NO:6 or SEQ ID NO:3. The optimal annealing temperature of each primer pair (taken as the highest annealing temperature which resulted in undiminished reaction yield) was determined in a 30 cycle conventional PCR using 25 ng of genomic DNA. At this point, SEQ ID NO:6 was replaced with another N. caninum-specific primer, SEQ ID NO:7, to overcome excessive amplification artefact formation encountered using SEQ ID NO:6, SEQ ID NO:8 and SEQ ID NO:5 together.
Reaction conditions for single tube nested PCR using the four primers were optimised using a 55 cycle PCR and 100 fg of genomic DNA. Starting conditions were identical to those used in conventional PCR, except the nested and flanking primers were present at concentrations of 50 μM and 2 μM respectively. Because of the large number of reaction variables important in single tube nested PCR (including reagent concentrations, cycle parameters and setup conditions), screening experiments were conducted to determine the parameters which could be modified to enhance amplification sensitivity and specificity. Primer concentrations, initial cycle parameters, hot start protocols and amount of sample (for tissue section extracts) were further optimised using a 55 cycle, 10 fg genomic DNA amplification to optimise the PCR for low copy number amplifications. To investigate any potential inhibitory effect of substances present in tissue sections, amplifications using 1, 10, 20 or 30 μl of negative control tissue section and 10 fg of genomic DNA were performed. Tissue sections through blood vessels containing approximately 30% blood cells (by area) were also tested, as compounds present in blood may inhibit PCR.
1.6 Specificity of optimised protocol
The specificity of the optimised single tube nested PCR protocols were evaluated by test 1 ng of genomic DNA from each N. caninum (NC-1 and NC-Liverpool isolates), T. gondii (RH- and ME49 strains), Sarcocystis cruzi, dog and cow.
1.7 Sensitivity of optimised protocol
The sensitivity of the optimised protocols were evaluated using serial tenfold dilutions of genomic DNA of either N. caninum or T. gondii genomic DNA. 10 replicates of 1 fg were tested.
1.8 Formalin-fixed, paraffin-embedded tissue sections
To investigate the utility of the optimised PCRs with clinical materials, Neospora-positive tissue sections from the brain of a dog and an aborted bovine foetus, a T. gondii-positive section from a dog, and negative control sections from a dog and a cow were tested by PCR. Tissue sections were prepared in a separate building from where PCR was performed to prevent false positive results due to contamination with amplification products. Each 5 μm tissue section was placed in a 600 μl microfuge tube with 300 μl of sterile distilled water, overlaid with 50 μl of mineral oil, and heated on a thermal cycler for 15 min at 99.9° C. The tube was allowed to cool to room temperature, and 5 μl of solution tested using each the N. caninum and T. gondii PCR. Immunohistochemistry using hyperimmune goat sera raised against N. caninum or T. gondii (VMRD, USA) and an avidin biotin peroxidase complex (Dako, Australia) was used in parallel with PCR as an indicator of true status.
2 RESULTS
2.1 Optimised single tube nested PCR protocol
Optimal conditions for both N. caninum and T. gondii were very similar. The final reaction conditions were 5 μl of test sample/1xPCR Buffer/0.2 mM each dNTP/50 μM each nested primer/0.5 μM each flanking primer/0.8 units of Taq DNA polymerase in a total reaction volume of 50 μl. The thermal cycler was programmed as follows: 95° C. for 5 minutes;
5 cycles of 94° C. for 30 seconds, 60° C. for 150 seconds, 72° C. for 30 seconds;
15 cycles of 88° C. for 30 seconds, 60° C. for 30 seconds, 72° C. for 30 seconds;
10 cycles of 88° C. for 30 seconds, 54° C. for 30 seconds, 72 °C. for 30 seconds;
20 cycles of 86° C. for 30 seconds, 54° C. for 30 seconds, 72° C. for 30 seconds; and finally 72° C. for 10 minutes.
Reaction setup was found to be extremely important in maximising the sensitivity of the PCR. Reactions promptly set up and placed in the thermal cycler were 10- to 100-fold more sensitive than reactions allowed to sit for several minutes at room temperature. "Hot start PCR" using ampliwax PCR gems (Perkin Elmer Cetas) did not further improve sensitivity.
Inhibition of amplification by tissue sections was not observed, even when up to 60% of the reaction volume was composed of boiled tissue section, or when tissue sections containing blood were used (data not shown).
2.2 Specificity of optimised protocol
The N. caninum single tube nested PCR amplified the predicted 146 bp product from both the NC-1 and NC-Liverpool isolates of N. caninum, but not from dog, cow, or either T gondii strain tested. The T. gondii single tube nested PCR amplified the predicted 183 bp product from both the RH and ME-49 strains of T. gondii, but not from the host animal controls or from either N. caninum isolate.
2.3 Sensitivity of optimised protocol
The N. caninum single tube nested PCR amplified the predicted 146 bp product from the 100 fg, 10 fg and two of five 1 fg N. caninum genomic DNA amplification reactions.
2.4 Formalin-fixed, paraffin-embedded tissue sections
The N. caninum single tube nested PCR amplified the predicted 146 bp product from a normal dog tissue section spiked with N. caninum genomic DNA. a Neospora-infected dog and Neospora-infected aborted bovine foetal brain sections, but not from the T. gondii infected dog brain, the normal dog brain or normal cow brain tissue sections. The T. gondii protocol amplified the predicted 183 bp product from a normal dog tissue section spiked with 10 fg of genomic DNA and from a T. gondii-infected dog brain section, but not from normal dog or cow brain sections, nor from the Neospora-infected dog or cow brain sections.
2.5 Comparative efficiency of immunohistochemistry and PCR diagnosis from tissue sections
To investigate the utility of the optimised PCRs with clinical materials, Neospora-positive tissue sections from the brain of a dog and an aborted bovine foetus, a T. gondii-positive section from a dog, and negative control sections from a dog and a cow were tested by PCR. Tissue sections were prepared in a separate building from where PCR was performed to prevent false positive results due to contamination with amplification products. Each 5 μm tissue section was placed in a 600 μl microfuge tube with 300 μl of sterile distilled water, overlaid with 50 μl of mineral oil, and heated on a thermal cycler for 15 min at 99.9° C. The tube was allowed to cool to room temperature, and 5 μl of solution tested using each the N. caninum and T. gondii PCR. Immunohistochemistry using hyperimmune goat sera raised against N. caninum or T. gondii (VMRD, USA) and an Avidin biotin peroxidase complex (Dako, Australia) was used in parallel with PCR as an indicator of true status. The results of N. caninum and T. gondii-specific PCR and immunohistochemistry are shown in Table 2.
TABLE 2______________________________________Results of histopathological, immunohistochemical examination and PCRtesting of tissue sections from 10 dogs with clinical signs suggestiveofneosporosis or toxoplasmosis. Brain Le- MuscleDog Lesions PCR IHC sions PCR IHC Diagnosis______________________________________1 + - T + - T toxoplasmosis (t)2 - - - + N N neosporosis (n)3 + N N + N N neosporosis4 + N,T N,T + N,T N,T both n and t5 + - - + N N neosporosis6 + - - + N N neosporosis7 + - - + - - unknown8 + N N + - - neosporosis9 + N N + N N neosporosis10 + N N + - - neosporosis______________________________________ N = N. caninum; T = T. gondii; + = present; - = absent
Brain and muscle tissues from 10 dogs with clinical signs suggestive of neosporosis or toxoplasmosis were tested using both the optimised single tube nested PCR and immunohistochemistry. Sections from the brain and muscle of 10 healthy dogs were used as normal controls. Three sections from both brain and muscle tissue were tested using each N. caninum and T. gondii-specific immunohistochemistry and PCR. One section from each tissue was stained with haematoxylin and eosin (H&E) for routine histopathological examination. Table 2 represents each tissue classified by the presence or absence of pathological changes suggestive of protozoal disease, and by the immunohistochemistry and PCR results. None of the normal control dogs tested positive for either N. caninum or T. gondii by either technique. In the tissues from the clinic dogs, organisms were sometimes detected in only a proportion of the sections examined from a tissue, though pathological changes were typically observed in each section examined. One of the clinic dogs tested positive for T. gondii only, seven dogs tested positive for N. caninum only, and one dog (#4) tested positive for both organisms. One dog (#7) tested negative for both organisms, despite having lesions in each tissue.
While PCR has been applied to the detection of a number of protozoa, including N. caninum and T. gondii, previously reported PCR protocols for these organisms have not exploited the potential sensitivity of this technique. The present inventors employed a second, nested amplification in a single tube to enhance the sensitivity and specificity of PCR protocols for the detection of N. caninum and T. gondii. The optimised single tube nested PCR was able to detect as little as 1 fg of genomic DNA, representing an improvement in sensitivity of around 700 times that of the conventional PCR protocol. The results observed with the 1 fg replicates are consistent with a Poisson distribution, suggesting the assay is capable of detect the presence or absence of a single copy of target sequence. Hence, performing nested amplifications in a single tube was effective in enhancing the sensitivity of a PCR for the detection of N. caninum or T. gondii. Successful amplification of parasite DNA from formalin-fixed, paraffin embedded tissue sections confirmed the suitability of the assay for testing clinical material from naturally infected animals. The single tube nested PCR was as sensitive as immunohistochemistry in detecting N. caninum infections in formalin-fixed, paraffin-embedded tissue sections.
In conventional PCR the number of cycles which can be profitably performed is limited by the formation of primer-dependant amplification artefacts (such as "primer dimers"). In singe-tube nested PCR, primers are designed such that flanking primers have a higher melting point than nested primers (by virtue of greater length or G+C content). A thermal profile is then employed which first allows selective annealing and extension of external but not nested primers. The annealing temperature then reduced, enabling annealing of the nested primers and amplification of the nested product from the initial product. A further reduction in the denaturation temperature prevents dissociation of the external product, resulting in selective annealing and extension of the nested primers in the later stages of amplification. Low concentrations of flanking primers and late entry of the nested primers into the amplification reaction delay the formation of nonspecific amplification products, allowing an increased number of thermal cycles and thus enhanced sensitivity. Amplification specificity is also enhanced, as any non-target sequences amplified by the flanking primers are extremely unlikely to support further amplification by the nested primers.
The optimised protocol according to the present invention incorporated several strategies to maximise amplification sensitivity and specificity. To minimise non-specific priming prior to the reactions reaching the denaturation temperature, preferably reagents and samples were kept chilled on ice, and reactions were promptly assembled and placed into a preheated thermal cycler. The denaturation temperature was reduced from 94° C. to 87° C. after the first five rounds to minimise spurious product formation and amplification inhibition associated with large amounts of non-specific DNA (this also reduced the duration of thermal cycling). An extended annealing time of 150 seconds was used for the first five cycles to ensure amplification of rare target sequences.
Had the single tube nested PCR protocol been developed de nova, flanking primers would have been designed longer than nested primers, to give an optimal annealing temperature close to 72° C., enhancing specificity and shorten thermal cycling time. The incorporation of a GC clamp (a tail of guanine and cytosine bases at the 5' end of flanking primers, which raises the denaturation temperature of the amplification product, allowing complete "drop out" of the flanking primer product with reduced denaturation temperature in the later cycles of amplification) might also have been considered. While the difference in annealing and denaturation temperatures for the nested and flanking primers and products in the present protocol is only small, the PCR is nonetheless robust and reliable.
To ensure amplification specificity, potential primers were selected from regions of consistent sequence intraspecific conservation and interspecific variation using alignments of the ITS1 region from NC-1 and NC-Liverpool isolates of N. caninum and RH, P and Sailie strains of T. gondii (Genbank accession numbers U16160. U16159, X75453, X75429 and X75430 respectively. Potential primers were selected from regions of consistent conservation. Amplification protocols for N. caninum and T. gondii were developed in parallel because of the difficulties in differentiating infections with these organisms clinically and with immunologic techniques. Furthermore, given the genetic similarity of these organisms, it was felt that T. gondii was the organism most likely to give false-positive results in the N. caninum PCR, and vice-versa. It was desirable that the N. caninum- and T. gondii-specific protocols utilise identical thermal cycle programs to allow both assays to be performed simultaneously on a single thermal cycler. The similarity of the two optimised PCR protocols is testimony to the sequence and structure conservation in the ITS1 region of these two organisms.
A suitable method of sample preparation for PCR is to lyse cells to release DNA into solution without damage or degradation of the DNA, and without introducing or co-purifying substances which may inhibit amplification. Furthermore, it should be simple and rapid where possible, to reduce processing time, labour and the risk of contamination. It has been found by the present inventors that simple boiling is sufficient preparation for amplification of parasite DNA from tissue sections and cerebrospinal fluid. Some samples, however, such as faeces, blood or solid tissues may warrant further treatment. Preparation of samples by boiling allowed results from a group of samples to be obtained within an 8 hour day.
While the examples of the present invention focussed on formalin-fixed, paraffin embedded tissue sections, the single tube nested PCR has also been used to amplify parasite DNA from cerebrospinal fluid, fresh, and ethanol-fixed tissues, and should be readily adapted for other types of clinical material. Formalin-fixed tissues were focussed upon because archival material was always available for testing, preparation was simple, and the presence of organisms could be readily verified using immunohistochemistry or routine histology. This tissue type was considered a suitably stringent test of the sensitivity of the assay, as formalin fixation results in loss and degradation of DNA. While flanking primers were selected so as to define as short an amplification product as practical, formalin-fixed tissues are inferior to fresh, frozen or ethanol-fixed tissues as PCR substrates. Tissues fixed with unbuffered formalin. Zenler's, Bouin's or B5 solutions aregenerally considered unacceptable samples for PCR.
Occasional false positive results (date to contamination of reactions with previously amplified DNA) encountered during the development of the assay were minimised by strict maintenance of aseptic technique and a clean to dirty flow of material, equipment and personnel. Test samples were prepared in a separate building from where PCR was performed, and PCR reactions were prepared in a separate area, and, where possible, prior to electrophoretic analysis of amplification products in both the daily and weekly routine. Despite these precautions, the exquisite sensitivity of the single tube nested PCR means that occasional false positive results are possible. Therefore several known negative samples and reagent controls were included in each diagnostic PCR run. While several chemical and enzymatic protocols for the prevention of carry over contamination have been described, these have been found to be of limited efficacy for short amplification products.
The single tube nested PCR of the present invention provides a complement or alternative to immunohistochemistry and routine histology in detecting organisms in biopsy and postmortem samples. Furthermore, the wide range of material amenable to PCR analysis allows diagnosis of infection and the detection of organisms from other clinical samples, such as blood product, cerebrospinal fluid, amniotic fluid, lung aspirates and semen will be possible, often with minimal sample preparation. With appropriate sample preparation and DNA purification protocols, the assay will be useful in detecting organisms in the environment, or the faecas of potential definitive hosts. The assay will be useful in the study of disease development, maintenance and progression of infections. Finally with appropriate sample preparation protocols, the assay will be useful in detecting organisms in the environment, or the faeces of potential definitive hosts. Hence the single tube nested PCR provides a powerful new tool in the study of N. caninum and T. gondii, and the diagnosis of infection in animals.
The results of this study demonstrated that single-tube nested PCR was a practical way of enhancing the sensitivity of the existing N. caninum and T. gondii ITS1 PCR protocols. The optimised assay was able to detect a single copy of target sequence, and was specific for the organism targeted. In addition, the assay was able to detect N. caninum and T. gondii microorganisms in formalin-fixed, paraffin-embedded tissue sections from naturally infected dogs.
It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.
References
Holmdahl, O. J. M. & Mattsson, J. G. (1996) Rapid and sensitive identification of Neospora caninum by in vitro amplification of the internal transcribed spacer 1. Parasitology 112, 177-182.
Guay, J. M., Dubois. D., Morency, M. J., Gagnong, S., Mercier, J. & Levesque, R. C. (1993) Detection of the pathogenic parasite Toxoplasma gondii by specific amplification of ribosomal sequences using comultiplex polymerase chain action. Journal of Clinical Microbiology 31, 203-207.
Dragon, E. A., Spadoro, J. P. and Madej, R. (1994) Quality Control of Polymerase Chain Reaction. In: Diagnostic Molecular Biology: Principles and Applications. (Persing, D. H., Smith, T. F., Tenover, F. C. & White, T. J.) Pp.161-169. Washington: American Society for Microbiology.
Payne, S. & Ellis, J. (1996) Detection of Neospora caninum DNA by the Polymerase Chain Reaction. International Journal of Parasitology 26, 347-351.
__________________________________________________________________________# SEQUENCE LISTING- (1) GENERAL INFORMATION:- (iii) NUMBER OF SEQUENCES: 9- (2) INFORMATION FOR SEQ ID NO:1:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 22 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:1: (xi) SEQUENCE DESCRIPTION: SEQ# 22CTT TA- (2) INFORMATION FOR SEQ ID NO:2:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 17 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:2: (xi) SEQUENCE DESCRIPTION: SEQ# 17 G- (2) INFORMATION FOR SEQ ID NO:3:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 17 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:3: (xi) SEQUENCE DESCRIPTION: SEQ# 17 G- (2) INFORMATION FOR SEQ ID NO:4:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 19 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:4: (xi) SEQUENCE DESCRIPTION: SEQ# 19 GTA- (2) INFORMATION FOR SEQ ID NO:5:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 21 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:5: (xi) SEQUENCE DESCRIPTION: SEQ#21 CCTG T- (2) INFORMATION FOR SEQ ID NO:6:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 18 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:6: (xi) SEQUENCE DESCRIPTION: SEQ# 18 TG- (2) INFORMATION FOR SEQ ID NO:7:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 17 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:7: (xi) SEQUENCE DESCRIPTION: SEQ# 17 A- (2) INFORMATION FOR SEQ ID NO:8:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 19 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:8: (xi) SEQUENCE DESCRIPTION: SEQ# 19 AAG- (2) INFORMATION FOR SEQ ID NO:9:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 19 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: cDNA#ID NO:9: (xi) SEQUENCE DESCRIPTION: SEQ# 19 AAA__________________________________________________________________________ | Method of detecting a protozoan parasite in a sample containing the parasite, the method comprising the steps of: (a) adding to the sample a pair of flanking oligonucleotide primers, at least one flanking primer being specific for and each being complementary to an opposite strand of a double stranded DNA molecule encoding the ITS1 of the protozoan parasite and flanking a region of the ITS1; (b) further adding to the sample a pair of nested oligonucleotide primers, each nested primer being specific for and complementary to an opposite strand of the DNA encoding the ITS1 of the protozoan parasite, the nested primers being complementary to the region of the ITS1 spanned by the flanking primers; (c) providing buffers, reagents, nucleotides and a thermostable DNA polymerase to the sample to form a reaction mixture; (d) heating the sample to a temperature such that the double stranded DNA encoding the ITS1 of the protozoan parasite denatures to form single stranded DNA molecules; (e) cooling the denatured sample to a temperature such that only the flanking primers anneal to their respective complementary sequences on the denatured DNA molecules; (f) heating the denatured and annealed sample to a temperature such that the DNA polymerase extends the primers to form new double stranded DNA molecules spanning the region of the ITS1 defined by the flanking primers; (g) repeating steps (d), (a) and (f) such that the number of copies of the region of DNA encoding the ITS1 region is amplified; (h) heating the sample to a temperature such that the newly amplified double stranded DNA encoding the ITS1 region denatures to form single stranded DNA molecules; (i) cooling the denatured sample to a temperature such that only the nested primers anneal to their respective complementary sequences on the denatured DNA; (j) heating the denatured and annealed sample to a temperature such that the DNA polymerase extends the primers to form new double stranded DNA molecules spanning the region of the ITS1 defined by the nested primers; (k) repeating steps (h), (i) and (j) such that the number of copies of the region of DNA is amplified; and (l) detecting the amplified DNA. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/212,182, filed Jun. 16, 2000.
TECHNICAL FIELD
[0002] The present invention relates to the field of using adjuvants to promote a specific type of immunological response.
BACKGROUND
[0003] The immune system has evolved two different types of adaptive immunity, each specialized for the elimination of a particular class of pathogens. In response to intracellular microbes, CD4+ T-helper (Th) cells differentiate into Th1 cells, which produce interferon γ (IFNγ) and interleukin (IL)-1, which, in turn, enhance cell-mediated immunity and inhibit the humoral immune responses. In contrast, helminths induce differentiation of CD4+ T-helper (Th) cells into Th2 cells, which produce cytokines (principally IL-4, IL-5, and IL-10) to induce immunoglobulin E (IgE) and eosinophil-mediated destruction of pathogens. The Th2 immune response inhibits cell-mediated immunity and enhances humoral immunity. The mechanism by which a given pathogen induces a Th1 or Th2 type of immune response is unknown.
[0004] Distinct subsets of dendritic cells (DCs) differentially induce Th1 and Th2 immune responses. In mice, the putative lymphoid-related CD8α+ DCs in spleens induce Th1 immune responses (Shortman, K. D., et al. 1998. “The linkage between T-cell and dendritic cell development in the mouse thymus,” Immune Rev 165:39-46). In contrast, Th2 immune responses are induced by the CD8α-myeloid DCs (Maldonado-Lopez, R., et al. 1999. “CD8α+ and CD8α− subclasses of dendritic cells direct the development of distinct T helper cells in vivo,” J Exp Med 189:587-592; Pulendran, B., et al. 1999. “Distinct dendritic cell subsets differentially regulate the class of immune response in vivo,” Proc Natl Acad Sci USA 96:1036-1041; Rissoan, M. C., et al. 1999. “Reciprocal control of T helper cell and dendritic cell differentiation,” Science 283:1183-1186). Different patterns of immunity can be elicited by activating distinct DC subsets.
[0005] [0005] Escherichia coli lipopolysaccharide (LPS) is reported to signal through the Toll-like receptor 4 (TLR4) complex (Qureshi, S. T., et al. 1999. “Endotoxin-tolerant mice have mutations in Toll-like receptor 4 (Tlr4),” J Exp Med 189:615-625; published erratum appears in J Exp Med 189:1518) and promote a Th1 immune response in vivo (Khoruts, A., A., et al. 1998. “A natural immunological adjuvant enhances T cell clonal expansion through a CD28-dependent, interleukin (IL)-2-independent mechanism,” J Exp Med 187:225-236). In contrast, Porphyromonas gingivalis LPS is reported to signal through a TLR4-independent mechanism (Tanamoto, K., S., et al. 1997. “The lipid A moiety of Porphyromonas gingivalis lipopolysaccharide specifically mediates the activation of C3H/HeJ mice,” J Immunol 158:4430-4436). It has now been found that although the LPS from these two different bacterial sources induce potent clonal expansion of antigen-specific CD4+ and CD8+ T cells in mice, they elicit strikingly different T cell cytokine profiles through differential cytokine expression by the CD8α+ and CD8α− DCs.
[0006] Although the use of adjuvants with antigen delivery to boost immunity is well known in the prior art, the adjuvants of the prior art reportedly elicit only a Th1 immune response. Currently, there is no known way to elicit a selective Th2 immune response with an adjuvant. A means of eliciting Th2 immune responses using P. gingivalis LPS has now been found, the application of the same to prevent and treat disease in humans and animals (mammals), increase antibody production in industrial practice, and to provide a method for studying the immune response in laboratory animals are presented herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] [0007]FIG. 1 depicts the experimental design utilized herein. B6.PL.THY1 a (B6.PL) mice or C57BL/6 mice reconstituted with OT-2 cells were injected with either soluble OVA, soluble OVA+ E. coli LPS, soluble OVA+ P. gingivalis LPS, E. coli LPS alone, or P. gingivalis LPS alone intraperitoneally or in the footpad. Four days later, the spleens (intraperitoneal route) or draining lymph nodes (footpad route) were removed for phenotypic and functional analyses, including clonal expansion of OVA-specific CD4+ T cells, in vitro proliferation of OVA-specific CD4+ T cells and cytokine production by the OVA-specific CD4+ T cells.
[0008] FIGS. 2 A- 2 G depict E. coli LPS and P. gingivalis LPS enhancing antigen-specific T-helper responses in vivo. B6.PL.THY1 a (B6.PL) mice reconstituted with OT-2 transgenic T cells were immunized with soluble OVA, E. coli LPS alone, P. gingivalis LPS alone, OVA+ E. coli LPS, or OVA+ P. gingivalis LPS, either subcutaneously in the footpad (FIGS. 2B, 2D and 2 F) or intraperitoneally (FIGS. 2C, 2E and 2 G). Four days later, the draining popliteal lymph nodes (subcutaneous route), or spleens (intraperitoneal route) were removed, and the clonal expansion of OVA-specific CD4+ T cells assessed by flow cytometry, by staining with Thy1.2 versus CD4. FIG. 2A depicts flow cytometry profiles from Day 4 of the response in the popliteal lymph nodes (subcutaneous route), from a representative experiment. FIGS. 2B and 2C depict the percentage expansion of OVA-specific CD4+ T cells (Thy1.2+, CD4+) in the draining lymph nodes and the spleens, respectively, at Day 4. Both E. coli LPS and P. gingivalis LPS significantly enhanced the clonal expansion, regardless of the route of injection. FIGS. 2D and 2E depict the absolute numbers of Thy 1.2+ CD4+ cells per popliteal lymph node or per spleen, respectively, at Day 4. FIGS. 2F and 2G depict in vitro restimulation of OVA-specific T cells expanded in vivo, by footpad injections or intraperitoneal injections, respectively. Four days after priming, single cell suspensions from the draining popliteal lymph nodes (FIG. 2F) or spleens (FIG. 2G) were restimulated with varying concentrations of OVA for 72 hours, and pulsed with [ 3 H] for 12 hours. Injections of E. coli LPS alone, or P. gingivalis LPS alone did not result in significant clonal expansion or in vitro proliferation. The data presented in FIGS. 2 A- 2 G are representative of ten independent experiments.
[0009] FIGS. 3 A- 3 H depict E. coli LPS and P. gingivalis LPS inducing distinct types of antigen-specific T-helper responses in vivo. Culture supernatants from the cultures described in FIG. 2F (subcutaneous injection) and FIG. 2G (intraperitoneal injection) were assayed for IL-2 (FIGS. 3A and 3E), IFNγ (FIGS. 3B and 3F), IL-10 (FIGS. 3C and 3G), IL-4 (data not shown), and IL-5 (FIGS. 3D and 3H) with ELISA. Injections of E. coli LPS alone or P. gingivalis LPS alone did not result in significant cytokine production. The data presented in FIGS. 3 A- 3 H are representative of ten independent experiments.
[0010] FIGS. 4 A- 4 G depict E. coli LPS and P. gingivalis LPS enhancing antigen-specific CD8+ T-cell responses in vivo. C57BL/6 mice, or B6.PL.THY1 a (B6.PL) mice reconstituted with OT-1 transgenic T cells were immunized with soluble OVA, OVA+ E. coli LPS, or OVA+ P. gingivalis LPS, either subcutaneously in the footpad (FIGS. 4B, 4D and 4 F) or intraperitoneally (FIGS. 4C, 4E and 4 G). Four days later, the draining popliteal lymph nodes (footpad injections) or spleens (intraperitoneal route) were removed, and the clonal expansion of OVA-specific CD8+ T cells assessed by flow cytometry, by staining with CD8 versus Vα2, or CD8 versus Thy1.2 versus Vα2. FIG. 4A depicts flow cytometry profiles from Day 4 of the response in the popliteal lymph nodes from a representative experiment. FIGS. 4B and 4C depict the percentage expansion of OVA-specific CD8+ T cells (CD8+ Thy1.2+) in the draining lymph nodes and the spleens, respectively, at Day 4. Both E. coli LPS and P. gingivalis LPS significantly enhance the clonal expansion, regardless of the route of injection. FIGS. 4D and 4E depict the absolute numbers of OVA-specific CD8+ T cells per popliteal lymph node or per spleen, respectively, at Day 4. FIGS. 4F and 4G depict in vitro restimulation of OVA-specific CD8+ T cells expanded in vivo, by footpad injections or intraperitoneal injections, respectively. Four days after priming, single cell suspensions from the draining popliteal lymph nodes (FIG. 4F) or spleens (FIG. 4G) were restimulated with varying concentrations of OVA for 72 hours, and pulsed with [ 3 H] for 12 hours. Injections of E. coli LPS alone or P. gingivalis LPS alone did not result in significant clonal expansion, or in vitro proliferation (data not shown). The data presented in FIGS. 4 A- 4 G are representative of three independent experiments.
[0011] FIGS. 5 A- 5 H depict E. coli LPS and P. gingivalis LPS inducing distinct types of antigen-specific CD8+ T-cell responses in vivo. Culture supernatants from the cultures described in FIGS. 3E and 3F were assayed for IL-2 (FIGS. 5A and 5B), IFNγ (FIGS. 5C and 5D), IL-10 (FIGS. 5E and 5F), IL-4 (data not shown), and IL-5 (FIGS. 5G and 5H) with ELISA. Injections of E. coli LPS alone or P. gingivalis LPS alone did not result in significant cytokine production (data not shown). The data presented in FIGS. 5 A- 5 H are representative of three independent experiments.
[0012] FIGS. 6 A- 6 L depict both E. coli LPS and P. gingivalis LPS activating CD8α+ and CD8α− DC subsets in vivo. C57BL/6 mice were injected with PBS (light histograms), or with E. coli LPS or P. gingivalis LPS (heavy, open histograms), either intravenously or intraperitoneally, and 6 hours later, the expression of CD80 (FIGS. 6A, 6D, 6 G, and 6 J), CD86 (FIGS. 6B, 6E, 6 H, and 6 K), and CD40 (FIGS. 6C, 6F, 6 I, and 6 L) assessed on gated, splenic CD11c+ CD8α+ and CD11c+ CD8α− DC subsets, by flow cytometry. Isotype controls are filled histograms. The data presented in FIGS. 6 A- 6 L are representative of three experiments.
[0013] FIGS. 7 A- 7 C depict E. coli LPS, but not P. gingivalis LPS inducing IL-12 in CD8α+ DCs. Splenic CD11c+CD8α+ and CD11c+CD8α DCs were isolated from C57BL/6 mice by microbead enrichment, followed by flow cytometry and stimulated in vitro with 10 μg/mL of E. coli LPS or P. gingivalis LPS. Culture supernatants were assayed for IL-12 (FIG. 7A), IL-6 (FIG. 7B), or TNFα (FIG. 7C) 24 hours later. The data presented in FIGS. 7 A- 7 C are representative of ten independent experiments.
[0014] [0014]FIGS. 8A and 8B demonstrate that TLR4 is the dominant receptor for signaling mediated by E. coli LPS, but not for P. gingivalis LPS. Splenocytes from C3H/HeJ mice and C3H/HeN mice were cultured with varying concentrations of E. coli LPS (FIG. 8A) or P. gingivalis LPS (FIG. 8B) for 72 hours. The cultures were pulsed with [ 3 H] during the last 12 hours of culture. The data presented in FIGS. 8 A- 8 B are representative of three independent experiments.
[0015] FIGS. 9 A- 9 D depict IL-6 production by splenocytes stimulated with E. coli LPS or P. gingivalis LPS in C3H/HeN and C3H/HeJ mice. Splenocytes from C3H/HeJ mice and C3H/HeN mice were cultured with varying concentrations of E. coli LPS for 12 hours or 48 hours (FIG. 9A and FIG. 9C, respectively) or P. gingivalis LPS for 12 hours or 48 hours (FIGS. 9B and 9D, respectively). IL-6 was measured by cytokine ELISA. The data presented in FIGS. 9 A- 9 B are representative of three independent experiments.
[0016] [0016]FIG. 10 depicts P. gingivalis LPS inducing much greater levels of IL-13 than E. coli LPS. B6.PL.THY1 a (B6.PL) mice reconstituted with OT-2 transgenic T cells were immunized with soluble OVA, E. coli LPS alone, P. gingivalis LPS alone, OVA+ E. coli LPS, or OVA+ P. gingivalis LPS, either subcutaneously in the footpad or intraperitoneally. Four days later, the draining popliteal lymph nodes (subcutaneous route), or spleens (intraperitoneal route) were removed, and single cell suspensions were restimulated with varying concentrations of OVA (0-500 μg/mL) for 72 hours, and pulsed with [ 3 H] for 12 hours. The cell populations were then assayed for IL-13 with ELISA. The data presented in FIG. 10 are representative of two independent experiments.
SUMMARY OF THE INVENTION
[0017] In one aspect, the invention is a use of an effective amount of adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for eliciting a Th2 response in a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0018] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for enhancing the immunogenicity of a vaccine in a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0019] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for modulating immunocompetence of a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0020] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for enhancing antibody harvest in a laboratory animal through elicited Th2 immune response. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0021] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for treating an autoimmune disease in a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0022] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for treating an infectious disease in a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0023] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for modulating the Th2 immune response in a laboratory animal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0024] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for stimulating IL-5 production in a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0025] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for stimulating IL-13 production in a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0026] In another aspect, the invention is a use of an effective amount of an adjuvant comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, for the preparation of a pharmaceutical composition for dampening IFNγ production in a mammal. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0027] In another aspect, the invention is a pharmaceutical composition comprising at least one isolated lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the pharmaceutical composition further comprises disease-specific antigens. In another embodiment, the pharmaceutical composition further comprises a co-adjuvant which elicits a Th1 immune response.
[0028] In another aspect, the invention is a method of eliciting a Th2 immune response in a mammal comprising administering an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0029] In another aspect, the invention is a method of enhancing the immunogenicity of a vaccine in a mammal comprising co-administering disease-specific antigens and an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0030] In another aspect, the invention is a method of modulating immunocompetence of a mammal comprising administering an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0031] In another aspect, the invention is a method of enhancing antibody harvest in a laboratory animal through elicited Th2 immune response comprising administering to the animal an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0032] In another aspect, the invention is a method for treating autoimmune disease in a mammal comprising administering to the mammal an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0033] In another aspect, the invention is a method for treating an infectious disease in a mammal comprising administering to the mammal an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0034] In another aspect, the invention is a method of modulating the Th2 immune response in a laboratory animal comprising administering to the mammal an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0035] In another aspect, the invention is a method of stimulating IL-5 production in a mammal comprising administering an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0036] In another aspect, the invention is a method of stimulating IL-13 production in a mammal comprising administering an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
[0037] In another aspect, the invention is a method of dampening IFNγ production in a mammal comprising administering an adjuvant comprising at least one lipid moiety selected from the group consisting of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof. In one embodiment, the method further comprises co-administering to the mammal disease-specific antigens. In another embodiment, the method further comprises co-administering to the mammal a co-adjuvant which elicits a Th1 immune response. The adjuvant, disease-specific antigens and, optionally, the co-adjuvant can be administered concurrently or sequentially.
DETAILED DESCRIPTION OF THE INVENTION
[0038] According to the present invention, P. gingivalis lipopolysaccharide (LPS) can be extracted from any isolated strain of Porphyromonas gingivalis . For example, P. gingivalis 33277, P. gingivalis 49417, and P. gingivalis 53978 from the American Type Culture Collection (Manassas, Va.) can be utilized. A clinical P. gingivalis isolate is another acceptable source for LPS extraction.
[0039] Although P. gingivalis LPS may be toxic from de novo preparations, it can be detoxified with existing technology without compromising its adjuvant activity (Rietschel, E. T., et al. 1994. “Bacterial endotoxin: molecular relationships of structure to activity and function,” FASEB Journal 8:217-825; Johnson, A. G., et al. 1987. “Characterization of a nontoxic monophosphoryl lipid A,” Rev Infectious Diseases 9 (Suppl 5):S512-S516). P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof can be used to induce a Th2 immune response in humans and animals for clinical benefit, experimental purposes, or industrial applications. A compound “derivative” is structurally similar and possesses similar immunologic properties to the compound itself and may be naturally occurring or synthetic.
[0040] In one aspect, the invention disclosed herein is the elicitation of a Th2 immune response through the administration of an adjuvant comprising one or more of the following: P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, or mimetics thereof. According to the instant invention, P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, and mimetics thereof, used singly or in any combination, are considered suitable for use as an adjuvant to produce a Th2 immune response in a human or animal. Moreover, P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, or a mimetic thereof can be used in combination with other adjuvants known in the art to modulate and induce immune responses in humans and animals.
[0041] The selective elicitation of the Th2 immune response is highly desirable for treatment or prophylactic vaccination of humans or animals against various autoimmune diseases and graft-versus-host disease. Many autoimmune diseases are characterized by pathogenic Th1 immune responses. Currently, there are intensive efforts to discover adjuvants that can redirect a pathogenic Th1 immune response towards a benign Th2 immune response. Activating a Th2 immune response in a human or animal suffering from an autoimmune disease may decrease the pathogenic Th1 immune response, thereby decreasing the debilitating inflammation characteristic of such diseases. According to the instant invention, this effect of activating a Th2 immune response in a human or animal can be achieved through administration of a therapeutically effective composition comprising P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof by methods well known in the art (Pulendran, B., et al. 2001. “Modulating the immune response with dendritic cells and their growth factors,” Trends in Immunology 22(1):41-47).
[0042] Therapeutic immunity against many tumors or infectious diseases or in transplantation requires Th2 immune responses. According to the instant invention, these diseases can be treated by administration of an adjuvant comprising P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof to induce a Th2 immune response.
[0043] Furthermore, therapeutic immunity against many tumors or infectious diseases often require both Th1 and Th2 immune responses simultaneously. According to the instant invention, P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof can be co-administered concurrently or sequentially with an adjuvant causing a Th1 immune response when a mixed response is required in the prevention or cure of diseases affecting humans or animals. This effect can be achieved through the introduction of a therapeutically effective amount of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof by methods well known in the art (Pulendran, B., et al. 2001. “Modulating the immune response with dendritic cells and their growth factors,” Trends in Immunology 22(1):4147).
[0044] Methods for administering an adjuvant for the purpose of modulating an immune response are well known in the art (Pulendran, B., et al. 2001. “Modulating the immune response with dendritic cells and their growth factors,” Trends in Immunology 22(1):41-47). To elicit a Th2 immune response, an adjuvant comprising P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof is preferably administered intravenously, intra-arterially, intra-muscularly, intra-dermally, and local (e.g., intra-tumoral or at the vicinity of a tumor site). Regardless of administration route, P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof can be administered with or without additional adjuvants and antigens. An effective amount of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof will elicit a Th2 immune response in a human or animal. A suitable pharmaceutical carrier or diluent for administering an effective amount of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof maintains the solubility of the compound. Formulating an effective amount of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof to elicit a Th2 immune response in a human or animal for oral administration is also contemplated.
[0045] In another aspect, the instant invention is a method of enhancing the immunogenicity of a vaccine by administering an adjuvant comprising one or more of the following: P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, or mimetics thereof. The adjuvant of the instant invention can be administered concurrently or sequentially with a vaccine to enhance immunity by eliciting a Th2 immune response. Sequential administration indicates that the adjuvant and vaccine may be injected separately, in any order. Preferred administration routes include intravenous, intra-arterial, intramuscular, intra-dermal, and local (e.g., intra-tumoral or at the vicinity of a tumor site). Methods for co-administering an adjuvant with a vaccine to increase immunoreactivity are well known in the art (Pulendran, B., et al. 2001. “Modulating the immune response with dendritic cells and their growth factors,” Trends in Immunology 22(1):41-47).
[0046] In addition to treating diseases, the instant invention includes use of adjuvants comprising P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof as research tools to study the immune system in laboratory animals. P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof can also be used in conjunction with an antigen for enhancing the production and harvest of antibodies in animals by methods well known in the art.
[0047] The following examples of the instant invention are illustrative of some of the applications of the invention but are not meant to be limiting in any way. Any use of P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof to induce a Th2 immune response is herein contemplated by the instant invention. It will be appreciated by those skilled in the art that the following methods and materials are exemplary and that other methods and materials may be employed to achieve the same result.
[0048] Mice
[0049] OT-2 TCR transgenic mice (strain 426-6), generated by Dr. W. Heath (Walter & Eliza Hall Institute, Melbourne, Australia) and Dr. F. Carbone (Monash University, Melbourne, Australia) were obtained from Dr. J. Kapp (Emory University, Atlanta). OT-1 TCR transgenic mice were purchased from Jackson Laboratory (Bar Harbor, Me.). C57BL/6 mice, B6.PL.THY1 a (B6.PL) mice, and C3H/HeJ mice were purchased from Jackson Laboratory (Bar Harbor, Me.). C3H/HeN mice were purchased from Harlan Sprague Dawley (Indianapolis, Ind.). All mice were kept in microisolator cages in a specific-pathogen free facility. For adoptive transfers, age matched, male C57BL/6 or B6.PL.THY1 a recipients were given 2.5×10 6 of either OT-2 cells or OT-1 TCR transgenic T cells intravenously.
[0050] LPS Purification
[0051] [0051] P. gingivalis strain A7436 (Hirschfeld, M., et al. 2001. “Signaling by toll-like receptor 2 and 4 agonists results in differential gene expression in murine macrophages,” Infect Immun 69:1477-1482) and E. coli strain 25922 (American Type Culture Collection, Manassas, Va.) were cultured under identical conditions and LPS purified as previously described (Cutler, C. W., et al. 1996. “Hemin-induced modifications of the antigenicity and hemin-binding capacity of Porphyromonas gingivalis lipopolysaccharide,” Infect Immun 64:2282-2287; Westphal, O., and K. Jann. 1965. “Bacterial lipopolysaccharides. Extraction with phenol water and further applications of the procedure,” Methods Carbohydrate Chem 5:83). LPS extraction was achieved by a hot-phenol-water method, followed by further purification using isopycnic density gradient centrifugation. Briefly, 10 g (wet weight) of bacterial cell pellet was suspended in 35 mL of pyrogen-free water, and then 35 mL of 90% phenol at 65° C. was added dropwise for 20 minutes and stirred constantly. The aqueous phase was separated by centrifugation at 7,000×g for 20 minutes and collected. This process was repeated, and the aqueous phase was pooled and dialyzed against deionized water for 3 days. The dialyzed LPS preparation was then subjected to cesium chloride isopycnic density gradient centrifugation (in 0.5837 g CsCl 2 per 4.4 mL of the LPS preparation) at 42,000 rpm for 72 hours in a Beckman L-60 Ultracentrifuge (Palo Alto, Calif.). The refractive indices of the gradient fractions were determined with a refractometer (Milton Roy, Rochester, N.Y.), and values were converted to density (grams per milliliter). Fractions containing LPS (density fractions between 1.42 and 1.52 g/mL) were pooled, dialyzed against distilled water for 3 days, lyophilized and stored at room temperature. LPS was analyzed for protein by the BCA protein assay (Pierce Chemical Company, Rockford, Ill.). LPS samples were also separated by sodium dodecyl-sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and stained for protein with Coomasie blue (Pierce Chemical Company, Rockford, Ill.). Selected samples were also subjected to proteinase K digestion and nuclease treatment and reanalyzed by SDS-PAGE to confirm the purity of the LPS moieties (Pierce Chemical Company, Rockford, Ill.).
[0052] Endotoxin-Free OVA
[0053] Chicken OVALBUMIN (OVA) (Sigma Chemical Co., St. Louis, Mo.) was freshly prepared in phosphate buffered saline (PBS) at a concentration of 20 mg/mL, and depleted of the endotoxin activity (measured by LAL QCL-1000 kit from Bio Whittaker, Walkersville, Md., using manufacturer's protocol dated 2000), with the Detoxi-Gel Affinity Pack Columns (Pierce Chemical Company, Rockford, Ill.). After depletion the endotoxin level was below the limit of detection of the LAL QCL-1000 kit (<0.1 EU).
[0054] Injections
[0055] Reconstituted mice (3-5 per group) were injected either intraperitoneally, or in the footpad, with either 2 mg OVA in saline, 2 mg OVA+25 μg E. coli LPS, or 2 mg OVA+25 μg P. gingivalis LPS. Endotoxin activity in saline was measured by LAL QCL-1000 kit, and observed to be below the detection limit. Prior to mixing with OVA, LPS was sonicated extensively, to ensure uniform mixing of micelles. Footpad injections were given in a volume of 25 μl. Intraperitoneal injections were given in a volume of 100 μl.
[0056] Flow Cytometry
[0057] For analyses of OT-2 cells from mouse strain 426-6, cell suspensions were prepared from the draining popliteal lymph nodes or spleens, and incubated on ice with PE-labeled anti-Thy1.2 (Pharmingen, San Diego, Calif.), FITC-labeled Vα2 (Pharmingen), Cy-Chrome labeled CD4 (Pharmingen) and Biotin-labeled Vβ5 (Pharmingen), followed by streptavidin allophycocyanin (APC) (Pharmingen). Alternatively, we used antibodies against Thy1.2 and CD4. For analyses of OT-1 cells from OT-1 TCR transgenic mice, cell suspensions of draining popliteal lymph nodes or spleens were stained with PE-labeled anti-Thy1.2 (Pharmingen, San Diego, Calif.), FITC-labeled Vα2 (Pharmingen), and Biotin labeled CD8 (Pharmingen), followed by streptavidin allophycocyanin (Pharmingen). Alternatively, we simply used antibodies against Vα2 and CD8. DCs were stained with FITC-labeled CD11c (Pharmingen), in combination with PE-labeled CD11b (Pharmingen), or biotin-labeled CD8α (Pharmingen), followed by streptavidin allophycocyanin (Pharmingen) using a FACSvantage flow cytometer (Becton Dickinson), equipped with Enterprise II laser (Coherent Radiation, Palo Alto, Calif.).
[0058] In Vitro Cultures
[0059] Four days after injecting with OVA or OVA+LPS, 2.5×10 5 popliteal lymph node cells (footpad injections) or splenocytes (intraperitoneal injections) were plated in triplicate in 96-well flat bottomed plates (Costar, Cambridge, Mass.) in 200 μl of RPMI complete medium (GIBCO BRL, Grand Island, N.Y., US) supplemented with 5% fetal bovine serum (FBS), together with different concentrations (0-500 μg/mL of OVA, or OVA peptide (SIINFEKL, SEQ ID NO:1) (New England Peptide Incorporated, Fitchburg, Mass.). Proliferative responses were assessed after 72 hours of culture in a humidified atmosphere of 5% CO 2 in air. Cultures were pulsed with 1.0 μCi [ 3 H] thymidine for 12 hours, and incorporation of the radionucleotide was measured by β-scintillation spectroscopy (Pulendran, B., et al. 1999. “Distinct dendritic cell subsets differentially regulate the class of immune response in vivo,” Proc Natl Acad Sci USA 96:1036-1041). For cytokine assays, aliquots of culture supernatants were removed after 72 hours, pooled, and assayed for the presence of IFNγ, IL-2, IL-4, IL-5, IL-10, and IL-13 by ELISA.
[0060] Cytokine ELISAs
[0061] IFNγ, IL-2, IL-10, IL-4, IL-5, IL-6, IL-12, IL-13 and TNFα were quantified by ELISA kits from Pharmingen (San Diego, Calif.) using manufacturer's instructions dated 2000.
[0062] Immunohistology/Confocal Microscopy
[0063] Cohorts of C57BL/6 mice were injected with either PBS, E. coli LPS (50 μg), or P. gingivalis LPS (50 μg), either intravenously or intraperitoneally. Spleens were removed 6 hours later and embedded in Tissue-Tek OCT compound (Miles, Elkhart, Ind.) by flash freezing in 2-methyl butane (Mallinckrodt, Paris, Ky.) cooled with liquid nitrogen. The frozen tissue was stored at −70° C. Six-micrometer sections were cut on a cryostat (Reichert Jung, Cambridge Instruments GmbH, Germany) and mounted onto poly-L-lysine-coated slides. Sections were air dried for 10 minutes, fixed in ice-cold acetone (Baxter Diagnostics, Deerfield, Ill.) for 10 minutes, air dried and stored.
[0064] Splenic sections were rehydrated with PBS, and blocked with PBS/5% bovine serum albumin (BSA)/1% goat serum for 20 minutes, and stained with FITC-conjugated anti-CD11c (Pharmingen, San Diego, Calif.) and PE-conjugated anti-CD4 (Pharmingen, San Diego, Calif.) for 1 hour. The sections were washed and coverslips mounted onto glass slides with Fluoromount (Southern Biotechnology Associates, Birmingham, Ala.). Confocal microscopy was performed using a TCS SP microscope equipped with argon and krypton ion lasers and a 10×HC PL-APO objective (Leica Microsystem, Heidelberg, Germany).
[0065] Purification of Dendritic Cells
[0066] CD11c+CD8α+ and CD11c+CD8α− DC subsets were purified from spleens as follows. Spleens of C57BL/6 mice were dissected, cut into small fragments and then digested with collegenase D (0.5 mg/mL; Boehringer-Mannheim, Mannheim, Germany) and Dnase I (40 mg/mL, Boehringer-Mannheim) in RPMI 1640 medium supplemented with 5% fetal calf serum (FCS) for 10 minutes at 37° C. Digested fragments were washed twice in PBS/5% FCS. Then, CD11c+ DCs were enriched using CD11c+ microbeads (Miltenyi Biotech, San Diego, Calif.). The enriched DCs were stained with FITC-conjugated CD11c (Pharmingen) and PE-conjugated CD8α+ (Pharmingen) and sorted into the CD11c+ CD8α+ and CD11c+ CD8α− subsets, using a FACSvantage flow cytometer (Becton Dickinson), equipped with Enterprise II laser (Coherent Radiation, Palo Alto, Calif.).
[0067] Induction of Cytokines from DC Subsets
[0068] CD11c+ CD8α+ and CD11c+ CD8α− were isolated by flow cytometry and cultured in RPMI complete medium supplemented with 5% FBS and with either 10 μg/mL E. coli LPS or 10 μg/mL P. gingivalis LPS for 24 hours or 48 hours.
EXAMPLE 1
E. coli LPS and P. gingivalis LPS Enhance Antigen-Specific T-Helper Responses In Vivo
[0069] We demonstrated that LPS from E. coli and P. gingivalis could enhance antigen-specific T-helper responses against a soluble protein using OVA as an example. We utilized OVA-specific, MHC class II-restricted (1-A b ), αβ T cell receptor (TCR) transgenic mice (OT-2 mice) because the CD4+OVA-specific T cells express Vα2 and Vβ5 (Barnden, M. J., et al. 1998. “Defective TCR expression in transgenic mice constructed using cDNA-based alpha- and beta-chain genes under the control of heterologous regulatory elements,” Immunol Cell Biol 76:34-40). TCR transgenic T cells were adoptively transferred into Thy-1 congenic B6.PL.THY1 a (B6.PL) mice, such that they constituted a small but detectable proportion of all T cells (Kearney, E. R., et al. 1995, “Antigen-dependent clonal expansion of a trace population of antigen-specific CD4+ T cells in vivo is dependent on CD28 costimulation and inhibited by CTLA-4,” J Immunol 155:1032-1036). In this system, the fate of OVA-specific, transgenic T cells was followed using the Thy1.2 antibody, which stains only the transferred cells. T cells with the phenotype Thy1.2+ CD4+ Vα2+ Vβ5+ was considered OVA-specific CD4+ T cells.
[0070] The reconstituted mice were injected with one of the following compositions: soluble endotoxin-free OVA, E. coli LPS alone, P. gingivalis LPS alone, OVA+ E. coli LPS, or OVA+ P. gingivalis LPS. Injections were either intraperitoneal or in a footpad (FIG. 1). Prior to the injection, the OVA was depleted of endotoxin contamination using methods described above. The CD4+ OVA-specific T cell response in either the draining lymph nodes or in the spleen was monitored by flow cytometry (FIG. 2A). Injection of OVA elicited a significant clonal expansion of the Thy 1.2+ CD4+ T cells in the draining lymph nodes from mice injected in a footpad FIGS. 2A, 2B and 2 D or intraperitoneally FIGS. 2C and 2E. However, P. gingivalis LPS was marginally more effective than E. coli LPS in enhancing the clonal expansion when the antigen was delivered subcutaneously (7.0% OVA+ E. coli LPS versus 9.4% OVA+ P. gingivalis LPS; FIGS. 2B and 2D).
[0071] We next demonstrated the in vitro proliferative capacity of the OVA-specific T cells from the cohorts of mice as well as the effect of the adjuvant in eliciting an immune response. Single cell suspensions of the draining lymph nodes were cultured with varying concentrations of OVA as described above. As shown in FIGS. 2F and 2G, mice that received an injection of OVA+ E. coli LPS or OVA+ P. gingivalis LPS had a greatly enhanced proliferative response compared with the mice that received OVA alone.
EXAMPLE 2
E. coli LPS and P. gingivalis LPS Induce Distinct Types of Antigen-Specific T-Helper Responses In Vivo
[0072] Cytokine production by antigen-specific T cells was measured by assaying the culture supernatants from the single cell suspensions of the draining lymph nodes described above for IL-2, IFNγ, IL-4, IL-10 and IL-5. Assessment of cytokine production in these cultures revealed significant differences between mice injected with OVA, OVA+ E. coli LPS, or OVA+ P. gingivalis LPS (FIGS. 3 A- 3 H). In cultures from mice injected with OVA alone, there was little, if any, IL-2, IFNγ, IL-10, IL-4, or IL-5 produced. In contrast, in cultures from mice injected with OVA+ E. coli LPS, there was significant IL-2 and IL-10 and very high levels of IFNγ produced by the antigen-specific T cells. Neither IL-4 nor IL-5 could be detected in cells from OVA+ E. coli LPS injected mice.
[0073] In cultures from mice injected with OVA+ P. gingivalis LPS, there was a striking diminution of IFNγ production, despite significant production of IL-2 and Th2 cytokines IL-10 and IL-5 (FIGS. 3 A- 3 H). In fact, the level of IFNγ was as low as that observed with OVA alone. Therefore, while both types of LPS elicit potent clonal expansion of antigen-specific CD4+ T cells in vivo, E. coli LPS induces a Th1-like response, characterized by high levels of IFNγ. In contrast, P. gingivalis LPS induces a response that is essentially devoid of IFNγ and characterized by significant levels of IL-10 and IL-5. It should be noted that the route of injection did not affect the pattern of cytokine production (FIGS. 3 A- 3 H). No significant levels of IL-4 could be detected in any of the conditions, which may reflect the Th1 bias of the C57BL/6 strain utilized.
EXAMPLE 3
E. coli LPS and P. gingivalis LPS Enhance Antigen-Specific CD8+ T-Cell Responses In Vivo
[0074] The dramatically different immune responses induced by E. coli LPS and P. gingivalis LPS suggested that there may be differences in antigen-specific CD8+ T cell responses. Using OT-1 mice (H12K b restricted, OVA-specific TCR-transgenic mice), we demonstrated that the distinct immune responses elicited by the different LPS molecules are due to the differences in antigen-specific CD8+ T cell responses (Hogquist, K. A., et al. 1994. “T cell receptor antagonist peptides induce positive selection,” Cell 76:17-27; Martin, S. and M. J. Bevan 1997. “Antigen-specific and nonspecific deletion of immature cortical thymocytes caused by antigen injection,” Eur J Immunol 27:2726-2736). Spleen cells (5×10 6 ) from OT-1 mice (B6.PL, Thy1.2) were adoptively transferred into B6.PL (Thy 1.1) hosts. Cohorts of host mice were injected with one of the following compositions: OVA, OVA+ E. coli LPS, or OVA+ P. gingivalis LPS. Clonal expansion of OVA-specific CD8+ T cells Thy1.2+, Vα2+ CD8+ was assessed by flow cytometry (FIGS. 4 A- 4 E). Both E. coli LPS and P. gingivalis LPS adjuvants enhanced the clonal expansion of OVA-specific CD8+ T cells.
[0075] Next, we demonstrated the in vitro proliferative capacity of the OVA-specific CD8+ T cells from the cohorts of mice by culturing single cell suspensions of the draining lymph nodes (subcutaneous route), or spleen (intraperitoneal route) with varying concentrations of OVA. As shown in FIGS. 4F and 4G, mice that received an injection of either OVA+ E. coli LPS or OVA+ P. gingivalis LPS had greatly enhanced proliferative responses, compared to cells from mice who received OVA alone.
EXAMPLE 4
E. coli LPS and P. gingivalis LPS Induce Distinct Types of Antigen-Specific CD8+ T-Cell Responses In Vivo
[0076] We next examined the cytokines produced in CD8+ T-cell cultures by ELISA. As observed with the CD4+ OT-2 cells, CD8+ OT-1 cells stimulated with OVA alone did not secrete significant levels of IL-2, IFNγ, IL-10, or IL-5 (FIGS. 5 A- 5 H). Cells from mice injected with OVA+ E. coli LPS produced very high levels of IFNγ (FIGS. 5B and 5F) and significant levels of IL-10 (FIGS. 5C and 5G), but no IL-5 (FIGS. 5D and 5H). In contrast, cells from mice injected with OVA+ P. gingivalis LPS produced much lower levels of IFNγ (FIGS. 5B and 5F), but significant levels of IL-10 (FIGS. 5C and 5G) and IL-5 (FIGS. 5D and 5H), consistent with the cytokine patterns observed with CD4+ OT-2 cells (FIGS. 3 A- 3 H). No significant levels of IL-4 were detected in any condition.
EXAMPLE 5
Both E. coli LPS and P. gingivalis LPS Activate CD8α+ and CD8α− DC Subsets In Vivo
[0077] All known adjuvants in the prior art are known to nonspecifically activate DCs, thereby enhancing T-cell immunity (Reis e Sousa, C. and R. N. Germain. 1999. “Analysis of adjuvant function by direct visualization of antigen presentation in vivo: endotoxin promotes accumulation of antigen-bearing dendritic cells in the T cell areas of lymphoid tissue,” J Immunol 162:6552-6561). We demonstrated that LPS originating from both E. coli and P. gingivalis were capable of activating DC subsets in vivo. C57BL/6 mice were injected with 25 μg of E. coli LPS or P. gingivalis LPS, either subcutaneously, intraperitoneally, or intravenously, and sacrificed 6 hours later. Spleens and lymph nodes were collected, and the expression of activation or maturation markers (CD80, CD86 and CD40) on DCs were determined. CD8α+ and myeloid CD8α− DCs from the spleens of PBS treated control mice express significant levels of CD80, CD86 and CD40 as reported previously (Pulendran, B., J., et al. 1997 “Developmental pathways of dendritic cells in vivo: distinct function, phenotype, and localization of dendritic cell subsets in FLT3 ligand-treated mice” J Immunol 159:2222-2231). In addition to this observation, upon injection of either type of LPS, there was a significant up-regulation of CD80, CD86 and CD40 on both DC subsets (FIGS. 6 A- 6 L). Therefore, both types of LPS appear to activate the CD8α+ and CD8α− DC subsets in vivo.
EXAMPLE 6
E. coli LPS, But Not P. gingivalis LPS Induces IL-12 in CD8α+ DCs
[0078] We demonstrated that IL-12 production in CD8α+ DCs only occurred with LPS from E. coli . DCs were enriched from the spleens of C57BL/6 mice as described previously. The CD11c+ CD8α+ and CD11c+ CD8α− DC subsets were isolated by flow cytometry, and cultured for 24 hours without additional material or with either E. coli LPS or P. gingivalis LPS. The supernatants were then assayed for the presence of IL-12, IL-6, and TNFα by ELISA. Both types of LPS induced IL-6, and TNFα in both DC subsets, but only E. coli LPS induced IL-12 in the CD8α+ DC subset (FIG. 7A). Therefore, while both types of LPS could activate both DC subsets, only the E. coli LPS could elicit the Th1 inducing cytokine IL-12. Although IL-10 and IL-13 may be Th2-inducing cytokines, significant levels of either IL-10 or IL-13 could not be consistently detected in these cultures.
EXAMPLE 7
TLR4 is the Dominant Receptor for Signaling Mediated by E. coli LPS, But Not for P. gingivalis LPS
[0079] Although E. coli LPS mediates its effects by signaling through Toll-like receptor 4 (TLR4), P. gingivalis LPS may signal through a TLR4-independent mechanism. We determined the effect of either type of LPS on proliferation of splenocytes from TLR4 deficient mice (C3H/HeJ mice) and wild type (C3H/HeN) mice. C3H/HeJ splenocytes cultured with E. coli LPS were greatly impaired in their proliferative capacity, compared to the C3H/HeN controls (FIG. 8A). In contrast, C3H/HeJ splenocytes cultured with P. gingivalis LPS were only modestly impaired in their proliferative capacity, compared to the C3H/HeN controls (FIG. 8B). Consistent with this, production of IL-6 induced by E. coli LPS was greatly impaired in C3H/HeJ splenocytes, compared to C3H/HeN splenocytes (FIGS. 9A and 9C). However, production of IL-6 induced by P. gingivalis LPS was not impaired in C3H/HeJ mice (FIGS. 9B and 9D). Therefore, as reported previously, while E. coli LPS signaling is largely dependent on TLR4, P. gingivalis LPS appears to signal mainly through a TLR4-independent mechanism. Therefore, as reported previously, E. coli LPS signaling is largely dependent on TLR4, whereas P. gingivalis LPS appears to signal mainly through a TLR4-independent mechanism.
EXAMPLE 8
P. gingivalis LPS, But Not E. coli LPS, Stimulates IL-13 Production
[0080] We next demonstrated that IL-13 production is stimulated by the adjuvant P. gingivalis LPS. Cytokine production by antigen-specific T cells was measured by assaying the culture supernatants from the single cell suspensions of the draining lymph nodes cultured with varying concentrations of OVA (0-500 μg/mL). Assessment of cytokine production in these cultures revealed significant differences between B6.PL.THY1 a (B6.PL) mice injected with OVA, OVA+ E. coli LPS, or OVA+ P. gingivalis LPS and the route of administration (FIG. 10). In cultures from mice injected with OVA alone intraperitoneally or subcutaneously, there was little, if any, IL-13, produced. In contrast, in cultures from mice injected intraperitoneally with OVA+ E. coli LPS, there was significant IL-13 produced by the antigen-specific T cells. Cultures from mice injected subcutaneously with OVA+ E. coli LPS did not greatly increase IL-13 production.
[0081] In cultures from mice injected with OVA+ P. gingivalis LPS, there was a striking increase of IL-13 production (FIG. 10). Mice injected subcutaneously with OVA+ P. gingivalis LPS produced much greater IL-13 than those mice injected intraperitoneally. However, even the intraperitoneal injection of OVA+ P. gingivalis LPS produced much greater IL-13 than those mice injected with OVA+ E. coli LPS. The production of IL-13, a specific cytokine for the Th2 immune response, in response to P. gingivalis LPS injection and not E. coli LPS injection, further demonstrates the selective Th2 immune response elicitation of P. gingivalis LPS.
[0082] Examples 1-8 have demonstrated that different microbial products may induce distinct types of immune responses via differential activation of DC subsets. E. coli LPS induced Th1 and Tc1 responses, with high levels of IFNγ, but no IL-4 or IL-5. In contrast, P. gingivalis LPS induced Th2 and Tc2 immune responses characterized by significant levels of IL-10, IL-13, and IL-5, but very little or no IFNγ. We have shown, for the first time, an adjuvant which selectively induces the Th2 immune response. The subject of Examples 9-12 is the application of the ability to selectively activate the Th2 immune response rather than the Th1 immune response. The subject matter of Examples 9-12 is meant to be illustrative and in no way limit the application of using P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof, to induce a Th2 immune response. It should also be understood to those skilled in the art that the applications described herein are not limited to humans.
EXAMPLE 9
Use of Adjuvant to Elicit Th2 Immune Response
[0083] The invention contemplates a method to elicit a Th2 or Th2-like immune response in a subject who suffers from a disease state that can be alleviated at least in part with an appropriate Th2 or Th2-like immune response. After identifying a disease state that may be alleviated at least in part with a Th2 or Th2-like immune response, the next step may be to determine disease specific antigens. The subsequent step may be to co-administer the disease specific antigens with P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof, to induce a Th2 immune response. Co-administration of disease specific antigens and adjuvants of the present invention that elicit a Th2 or Th2-like immune response can be sequentially or concurrently delivered intravenously, intra-arterially, intra-muscularly, intra-dermally, intra-tumorally, or orally. Any pharmaceutical carrier or diluent that maintains the solubility of the components can be used.
EXAMPLE 10
Modulating the Balance of Th1 and Th2 Immune Responses for Treating Disease States
[0084] The invention contemplates a method to elicit a Th2 or Th2-like immune response in a subject who suffers from a disease state in which an inappropriate Th1 immune response is associated. The method can be implemented to alleviate at least in part an inappropriate Th1 immune response by shifting the response away from the Th1 to a Th2 or Th2-like immune response. After identifying a disease state that may be alleviated at least in part with a Th2 or Th2-like immune response, the next step may be to determine disease specific antigens. The subsequent step may be to co-administer the disease specific antigens with P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof, to induce a Th2 immune response. Co-administration of disease specific antigens and adjuvants of the present invention that elicit a Th2 or Th2-like immune response can be sequentially or concurrently delivered intravenously, intra-arterially, intra-muscularly, intra-dermally, intra-tumorally, or orally. Any pharmaceutical carrier or diluent that maintains the solubility of the components can be used.
EXAMPLE 11
Using P. gingivalis LPS in Conjunction with Other Adjuvants to Elicit a Combined Th1/Th2 Immune Response
[0085] The invention contemplates a method to elicit both a Th1 and a Th2 or Th2-like immune response in a subject who suffers from a disease state that can be alleviated at least in part with a combined Th1 and Th2 or Th2-like immune response. After identifying a disease state that may be alleviated at least in part with a combined Th1 and Th2 or Th2-like immune response, the next step may be to determine disease specific antigens. The subsequent step may be to co-administer the disease specific antigens with P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof, and at least one adjuvant known to induce a Th1 immune response, to induce a combined Th1/Th2 immune response. Co-administration of disease specific antigens, adjuvants for a Th1 immune response, and adjuvants of the present invention that elicit a Th2 or Th2-like immune response can be sequentially or concurrently delivered intravenously, intra-arterially, intra-muscularly, intra-dermally, intra-tumorally, or orally. Any pharmaceutical carrier or diluent that maintains the solubility of the components can be used.
EXAMPLE 12
Using P. gingivalis LPS as a Vaccine Adjuvant
[0086] The invention contemplates a method to elicit a Th2 or Th2-like immune response in a subject to prevent disease onset. After identifying a disease state that may be prevented with a Th2 or Th2-like immune response, the next step may be to determine disease specific antigens. The next step may be to co-administer the disease specific antigens with P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, mimetics thereof, or any combination thereof, to induce a Th2 immune response. Co-administration of disease specific antigens and adjuvants of the present invention that elicit a Th2 or Th2-like immune response can be sequentially or concurrently delivered intravenously, intra-arterially, intra-muscularly, intra-dermally, or orally. Any pharmaceutical carrier or diluent that maintains the solubility of the components can be used.
1
1
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PRT
chicken
PEPTIDE
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1
Ser Ile Ile Asn Phe Glu Lys Leu
1 5 | Porphyromanas gingivalis LPS elicits a Th2 immune response. P. gingivalis LPS, detoxified P. gingivalis LPS, derivatives of P. gingivalis LPS, derivatives of detoxified P. gingivalis LPS, P. gingivalis Lipid A, detoxified P. gingivalis Lipid A, derivatives of P. gingivalis Lipid A, derivatives of detoxified P. gingivalis Lipid A, or mimetics thereof, can be used as adjuvants to elicit a Th2 immune response, increase the efficacy of vaccinations in infectious diseases, decrease the severity of autoimmune responses, boost the Th2 immune response when needed in combination with the Th1 immune response, facilitate the industrial production of antibodies when used in animals, and study the Th2 immune response in laboratory research. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to the extraction of fiber flocks from textile bales in general, and more particularly to a method and an arrangement for accomplishing such extraction in a controlled manner in dependence on the characteristic properties of the bales and their material.
There is already known a bale opening machine which is distributed under the trademark UNIFLOC by the assignee of the present invention and in which a flock extraction device is mounted on a carrier which is movable back and forth along the bales. This known arrangement renders it possible to extract fiber flocks from bales having different dimensions and particularly heights and/or containing different fiber materials. The extraction device of this known arrangement includes a fiber extraction member which passes between grid bars and projects to a predetermined extent beyond such grid bars.
During the use of this arrangement for fiber flock extraction, the grid bars also penetrate into the surface layer of the respective bale, but the depth of such penetration of the grid bars into the surface layer of the bale is less than that of the extraction member by the aforementioned predetermined extent. The penetration of the extraction member into the surface layer of the bale is often referred to as the extraction or penetration depth and it can vary in dependence on the extraction power.
German published patent application DE-OS No. 32,45,506 discloses a device in which the extraction member can penetrate with a variable force into the bale surface layer in dependence on the density of the bale layer to be opened.
Variation of the fiber type, and the extraction conditions which result therefrom, were not taken into consideration in the known methods and arrangements which have been mentioned above.
SUMMARY OF THE INVENTION
Accordingly, it is a general object of the present invention to avoid the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a method of extracting fiber flocks from textile bales, which does not possess the disadvantages of the known methods of this kind.
Still another object of the present invention is so to devise the method of the type here under consideration as to render it possible to easily accommodate the arrangement employing this method to varying operating conditions.
It is yet another object of the present invention to develop an arrangement which is especially suited for the performance of the above method.
A concomitant object of the present invention is so to construct the arrangement of the above type as to be relatively simple in construction, inexpensive to manufacture, easy to use, and reliable in operation nevertheless.
In pursuance of these objects and others which will become apparent hereafter, one feature of the present invention resides in a method of extracting fiber flocks from textile fiber bales by an extraction member which extends between and beyond grid bars and penetrates into the surface layer of the respective fiber bale to extract the fiber flocks therefrom for transfer to a flock transport system, such method comprising the step of varying the extent to which the extraction member extends beyond the grid bars in dependence on at least one of the density and the type of the fiber material of the surface layer.
According to another aspect of the present invention, this method can be used in an application in which the extraction member moves in a plurality of passes over the respective fiber bale and extracts the fiber flocks from the surface layer thereof to a predetermined penetration depth during each pass. Then, the method further comprises the step of changing the penetration depths for different passes independently of the varying step in dependence on at least one of the bale height, the density, and the type of the fiber material of the surface layer.
It is also advantageous when the method of the present invention is used in an application in which the extraction member extracts the fiber flocks from a plurality of textile bales of different bale heights and/or fiber types. In this case, the varying step includes adjusting the extent of penetration of the extraction member from one bale of the plurality to another in dependence upon at least one of the height and the fiber type of the particular bale.
According to another concept of the present invention, there is provided an arrangement for extracting fiber flocks from fiber bales, such arrangement comprising an extraction device including a plurality of grid bars which penetrate during an extraction operation into a surface layer of the respective bale; an extraction member which extends between and beyond the grid bars to penetrate into the surface layer of the respective fiber bale to an extent exceeding the penetration of the grid bars into the surface layer to extract the fiber flocks from the surface layer; and means for varying the extent to which the extraction member extends beyond the grid bars in dependence on the requirements of the particular extraction operation.
An advantageous construction of the above arrangement is obtained when such arrangement further comprises a reciprocating device operative for moving the extraction device down and up relative to the bales to cause the extraction member to penetrate into the surface layer of the respective bale to a predetermined penetration depth and move away from the bale, respectively; and programmable controlling means for controlling the operation of at least one of the reciprocating device, the grid bars and the extraction member for adjusting the aforementioned extent in dependence on at least one of the fiber type and the penetration depth.
Last but not least, it is advantageous when the reciprocating device includes a pulse generator operative for issuing signals representative of the up and down movement of the extraction device, when there are provided respective switch elements operative for issuing respective position signals when the extraction device reaches its upper and lower end positions, respectively, and a sensor element mounted on the extraction device and operative for issuing an additional signal when the extraction device has reached the bale surface during its downward movement, and when the programmable controlling means includes a microprocessor operative for controlling the adjustment of the extent of penetration of the extraction member on the basis of the above-mentioned signals and in dependence on at least one of a predetermined penetration depth and fiber type of the particular bale.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved fiber flock extraction arrangement itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a somewhat simplified cross-sectional view of a flock extraction device embodying the present invention, taken on line I--I of FIG. 2;
FIG. 2 is a sectional view of the flock extraction arrangement taken on line II--II of FIG. 1; and
FIG. 3 is a side elevational view of a machine incorporating the flock extraction arrangement of FIGS. 1 and 2, taken in the direction of the arrow III in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawing in detail, and first to FIG. 1 thereof, it may be seen that the reference numeral 1 has been used therein to identify an apparatus for extracting fiber flocks (not shown) from fiber bales 2. The apparatus 1 comprises a fiber extraction member 3 which includes a rotatable shaft 5 having toothed discs 4 mounted thereon.
A housing 6 of the apparatus 1 includes housing walls 7 and 8 that enclose the fiber extraction member 3 in such a manner that fiber flocks (not shown) which are extracted by the teeth of the toothed discs 4 from the fiber bales 2 can be forwarded into a pneumatic flock transport duct 9 formed by an upper portion of the housing 6. The extracted flocks are forwarded in the direction of an arrow F when the extraction member 3 rotates in the direction of an arrow E, while the forwarding of the extracted flocks occurs in the direction of an arrow G when the extraction member 3 rotates in the direction of an arrow H.
In order to enable flock extraction, the toothed discs 4 pass between grid bars 10 and project by a predetermined distance M beyond these grid bars 10. The grid bars 10 also penetrate into the surface layer of the fiber bales 2 but by an amount which is less by the distance M than the extent of penetration of the discs 4 into the bales 2.
In order to enable variation of the distance M, the grid bars 10 are secured to longitudinal supports 11 and 12 which can be moved up or down by means of screw-threaded spindles 13. In turn, the spindles 13 are constituted by extended shafts of gear stop motors 14, which are supported by means of brackets 15 on the walls 7 and 8, respectively. As seen in FIG. 2 of the drawing, there are provided two screw-threaded spindles 13 for each longitudinal support 11 and 12.
In operation, all motors 14 must be operated simultaneously in order to raise or lower the grid bars 10. For safety, and in order to ensure the requisite precision of movement of the grid bars 10, the number of revolutions of the rotatable part of each of the motors 14 is controlled and correspondingly synchronized.
A simpler, non-illustrated embodiment comprises only one gear stop motor and transmission from this motor to the other three spindles 13 is effected, for example, by a conventional type of chain transmission.
The shaft 5 of the extraction member 3 is rotatably supported at one of its ends in a bearing 17 secured in one end wall 16 of the housing 6, and is connected at its other end to a drive (not shown). It may be seen in FIG. 2 that a grid bar 10 is present on each side of each of the toothed discs 4. In principle, there is also the possibility of making the extraction member 3 adjustable instead of the grid bars 10; for example, the bearings receiving the shaft 5 could be adjustably arranged. It is also conceivable that the grid bars 10 and the extraction member 3 could be so constructed and mounted as to be mutually adjustable.
In operation, as indicated in FIG. 1, the extraction apparatus 1 is moved back and forth over the fiber bales 2 in the directions identified by a double-headed arrow R.
FIG. 3 of the drawing illustrates a machine 20 for extracting fiber flocks from bales 2, this machine 20 comprising the extraction apparatus 1. In addition to the extraction apparatus 1, the machine 20 comprises a machine frame 21 and a flock transport system 22. The transport path and transport devices situated between the flock forwarding duct 9 and the flock transport system 22 are not illustrated since they are well known and are not the subject of this invention.
The extraction apparatus 1 is movable up and down in the direction of a double-headed arrow N by means of rollers 24 rotatably mounted on the extraction apparatus 1 and guided on guide rails 23 of the machine frame 21. However, only one roller pair 24 and only one rail 23 are illustrated in FIG. 3; rollers 24 and rail 23 which are similarly arranged on the opposite side are not visible in FIG. 3.
Furthermore, the extraction apparatus 1 comprises a projection 25 which is fixedly secured to a chain 26 of a chain transmission 27. The chain transmission 27 further comprises an upper, rotatably supported chain sprocket 28 for guiding the chain 26, and a lower chain sprocket 29 for driving this chain 26. The lower chain wheel 29 is fixedly secured to a drive shaft 30 of a gear transmission 31 for joint rotation therewith. An electric motor 32 is connected to the gear transmission 31 and serves as a source of energy therefor, this motor 31 also being constructed as a stop motor. The machine frame 21, the guide rails 23, the chain transmission 27, the gear transmission 31 and the electric motor 32 will be collectively referred to herein as a reciprocating apparatus.
At its upper end, as viewed in the FIG. 3 of the drawing, the shaft 33 of the motor 32 carries a toothed wheel 34 rotatable with the shaft 33. The wheel 34 functions as a counter wheel cooperating with a magnetic sensor 35 in such a manner that the sensor 35 constitutes a pulse generator. The output pulses from the pulse generator 35 are fed via a lead 36 to a microprocessor 37. The sensor 35 is of a commercially available type and emits a pulse each time it is passed by a tooth of the toothed wheel 34. The sensor 35 is stationary.
An upper end switch 38 and a lower end switch 39 are provided on the machine frame 21 and are operative for sensing the upper and lower end positions of the extraction apparatus 1, respectively. The upper end switch 38 is operated by an upper surface 40 of the projection 25 and the lower end switch 39 is operated by a lower surface 41 of the projection 25. The upper end switch 38 supplies an output pulse to the microprocessor 37 via a lead 42 and the lower end switch 39 supplies its output pulse to the microprocessor via a lead 43.
The extraction apparatus 1 is further provided, on its lower side 44 facing the fiber bales 2, with a light barrier including a light generator 45 and an optical receiver 46. The light barrier 45 and 46 is so arranged that the light generator 46 generates a light beam 47 extending at least over the entire length of the fiber extraction member 3; the light beam 47 is transformed in the optical receiver 46 into an electrical signal supplied via a lead 48 to the microprocessor 37. A further lead 49 connects the electric motor 32 with the microprocessor 37.
Finally, the machine frame 21 is arranged for movement (not indicated in the drawing) along the fiber bales 2 and above the flock transport system 22. This movement is enabled by wheels 50 drivably mounted on the machine frame 21 and running on rails 51 which are secured to the floor 52 of the spinning mill.
In operation, the fiber bales 2 are laid out in a known manner in groups (not shown), namely so that bales 2 of substantially the same height are arranged together in a respective bale group and a spacing of 1.2-1.5 meters is maintained between the individual bale groups. For locating the machine frame 21 in its end positions and in its positions between the individual bale groups, a sensor 53 is provided on the underside of the machine frame 21 and so-called positioning elements 54 are provided over the entire length along which the machine 20 can travel; the positioning elements 54 are movably arranged on one rail 55. The presence of these positioning elements 54 is sensed by the sensor 53 and indicated via a lead 56 to the microprocessor 37.
The previously mentioned end positions comprise, on the one hand, a starting position of the machine 20 at the beginning of the rails 50, from which starting position the movement of the machine 20 commences, and on the other hand, a final position at which the machine 20 changes its direction of travel. The distribution of the positioning elements 54 is effected in such a manner that the machine 20 with the extraction member 3 is halted ahead of the first bale group, or behind the last bale group, or between the individual bale groups.
In order to extract the fiber flocks from the bales 2 with a variable penetration depth corresponding to the density of the fiber material of the bales 2, but with a substantially constant extraction power, the bale height is divided into three or four zones. In the example presented here, there are four such zones indicated at A, B, C and D. The extraction procedure begins in the following manner:
Prior to the first extraction step, the extraction member 3 travels over the path from the upper end switch 38 to the lower end switch 39. In the course of this movement, the microprocessor 37 counts the number of pulses generated by the magnetic sensor 35 in response to the pass of the teeth of the toothed wheel 34 past the magnetic sensor 35 and registers thereby the sum of all these pulses, this sum being representative of the spacing between the lower and upper end positions.
Thereafter, the microprocessor 37 is programmed for flock extraction in the following manner:
First of all, two items of data are entered into the microprocessor 37, namely the predetermined penetration depth per pass of the extraction member 3 over the bale groups for the zone A, and the number of passes which are to be carried out with this penetration depth; this gives a height Ha. Then, the number of passes for the zone B is entered. The penetration depth for the zone B is calculated by the microprocessor 37. This penetration depth is reduced in a stepwise manner during the entered number of passes, namely from the penetration depth of the zone A to the penetration depth of the zone C. The height Hb is derived from the calculation by the microprocessor 37. Thereafter, the penetration depth for the zone C is entered.
As a modification, instead of entering the penetration depth per pass for the zone C, the weight of the complete bale layout and the required production rate per hour can be entered. From this data, together with the bale height, the microprocessor 37 calculates the penetration depth for all bale groups in such a manner that flock extraction is completed for all bale groups simultaneously.
Further, the penetration depth for the last pass, and the number of passes for the zone D, are entered. During these passes, the penetration depth is increased stepwise from the penetration depth for the zone C to that of the final pass. From this data, the microprocessor 37 calculates the height Hd of the zone D and thus the start of the penetration depth which is increased again in this zone D. The height Hc of the zone C is derived from the total height minus the heights Ha, Hb and Hd.
Finally, the distance M is programmed into the microprocessor 37 in dependence upon the fiber material of the individual bale groups or bales 2, so that, when corresponding signals are obtained from the corresponding positioning element 54, the distance M is adapted to the fiber material of the bale groups or bales 2 to be processed.
After the above-mentioned programming steps, the machine 20 is put into its flock extraction mode by an attendant who presses a start button (not shown) at this time.
Upon operation of the upper end switch 38, the machine 20 travels, with the extraction apparatus 1 in the upper end position, from its starting position on the rails 51 over the bales 2 laid out on the floor 52. After passing over the first positioning element 54, which is indicated by the sensor 53, the machine 20 continues to travel for several seconds so that the extraction apparatus 1 is located above the bale group. Thereafter, the extraction apparatus 1 is lowered in response to a control command of the microprocessor 37 supplied to the motor 32 via the lead 49. The lowering of the extraction apparatus 1 continues until the light beam 47 is interrupted by the bales 3. Due to this lowering until the interruption of the light beam 47, the pulses generated by the magnetic sensor 35 in response to the movement of the toothed wheel 34 are continually subtracted in the microprocessor 37 from the previously obtained total pulse sum, so that, when the extraction apparatus 1 comes to a stop as a result of the interruption of the light beam 47, the height of this bale group is determined.
If additional bale groups are present, the machine 20 automatically travels further until the next positioning element 54 is detected. The machine 20 is then stopped in a similar manner and the extraction apparatus 1 again travels into the upper end position. After the machine 20 has travelled so far past the lastmentioned positioning element 54 that the extraction apparatus 1 is again located over the next bale group, the height of this bale group is again determined in the previously mentioned manner. The same operation is carried out for all further bale groups.
After the determination of all bale group heights, the extraction apparatus is lowered before each pass over a bale group for extraction of fiber flocks from the bale surfaces by a penetration depth amount entered into or calculated by the microprocessor 37. These penetration depths can be different for each bale group in dependence upon the respective bale height. Switching of the penetration depths for flock extraction from one bale group to the penetration depth for the next bale group, and the adjustment of the distance M, is carried out automatically by the microprocessor 37. The penetration depths and number of the passes, and thus the zone heights, can be adapted at any time without interruption of the extraction procedure. The same applies to the adjustment of the distance M.
The flock transport system 22 can comprise a pneumatic transport duct (FIG. 3) or a transport conveyor (not shown) or any other transport means suitable for fiber flocks. Finally, the reciprocating apparatus can consist of other elements suitable for raising and lowering the extraction apparatus 1; it is not limited to the illustrated elements.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of arrangements differing from the type described above.
While the invention has been illustrated and described as embodied in an arrangement for extracting fiber flocks from bales of different heights, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic and specific aspects of our contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the claims.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims. | An arrangement for extracting fiber flocks from textile fiber bales includes a fiber flock extraction member which passes between and projects to a predetermined extent beyond respective grid bars which rest on the bale surface during the extraction operation, for the extraction member to extract the fiber flocks from the surface layer of the bale. The extent to which the extraction member extends beyond the grid bars can be adjusted in dependence on the fiber type. To achieve this, the grid bars are movable with respect to the extraction member by respective screw-threaded spindles. This adjustment is performed under the control of a suitable control system, especially a microprocessor, such that the extent of projection of the extraction member beyond the grid bars is automatically accommodated to the fiber type of each bale or bale group from which the fiber flocks are to be extracted during a particular extraction operation. | 3 |
RELATED APPLICATION
The present application is a divisional application of U.S. patent application Ser. No. 09/633,728 titled, “THERMOSTATIC MIXING VALVE” filed Aug. 7, 2000, now U.S. Pat. No. 6,315,210 which is a continuation of then U.S. patent application Ser. No. 09/165,880 titled “THERMOSTATIC MIXING VALVE,” filed Oct. 2, 1998 now abandoned, which applications are hereby incorporated by reference herein.
FIELD OF THE INVENTION
The present invention relates to a thermostatic mixing valve.
BACKGROUND OF THE INVENTION
Thermostatic mixing valves are known for the producing of a mixed fluid by combining the supplies of a first (relatively hot) fluid and of a second (relatively cold) fluid. Known arrangements for thermostatic mixing valves generally include a first fluid inlet, a second fluid inlet, a mixed fluid outlet, a mixing chamber, and a thermostatic control device. Known the thermostatic mixing valves generally vary the flow rate of at least the first fluid and often also of the second fluid, the temperatures, pressures, and flow rates of both of which are typically not known and may vary randomly during operation, to produce a mixed fluid of a substantially constant temperature.
It would be advantageous to provide for a thermostatic mixing valve to allow relatively high flow rates of first, second, and mixed fluids while incurring only relatively moderate pressure drops within the thermostatic mixing valve. It would also be advantageous for a thermostatic mixing valve to automatically shut off flow of at least a hot fluid upon failure of the thermostatic control device. It would further be advantageous to provide for a thermostatic mixing valve which allows for relatively high flow rates with only moderate pressure drops and which shuts off flow of at least the hot fluid.
SUMMARY OF THE INVENTION
The present invention relates to a thermostatic mixing valve configured to produce a mixed fluid substantially of a particular temperature from the mixing of a first fluid of a temperature higher than or equal to the particular temperature and of a second fluid of a temperature lower than or equal to the particular temperature. The thermostatic mixing valve includes a valve body having a first fluid inlet, a second fluid inlet, and a mixed fluid outlet. The thermostatic mixing valve also includes a valve member configured to control the rate of flow of at least the first fluid. The valve member includes a thermostatic control device in communication with the mixed fluid and a shuttle coupled to the thermostatic control device, configured for movement within a liner, and oriented to adjustably engage the flow of at least the first fluid through at least one opening within a wall of the liner, the direction of movement of the shuttle with respect to the liner defining the major longitudinal axis of the thermostatic mixing valve, the direction of flow of the first fluid being at least partially transverse with respect to the major longitudinal axis of the valve.
The present invention also relates to a thermostatic mixing valve configured to produce a mixed fluid substantially of a particular temperature from a first fluid of a temperature higher than or equal to the particular temperature and a second fluid of a temperature lower than or equal to the particular temperature. The thermostatic mixing valve includes a valve body having a first fluid inlet, a second fluid inlet, and a mixed fluid outlet, and a valve member configured to control the rate of flow of the first fluid and the rate of flow of the second fluid. The valve member includes a thermostatic control device in communication with the mixed fluid and a shuttle coupled to the thermostatic control device, configured for movement within a liner, and oriented to adjustably engage in opposing relationship the flow of the first fluid and the flow of the second fluid, the direction of movement of the shuttle with respect to the liner defining the major longitudinal axis of the thermostatic mixing valve, the directions of flow of the first fluid and the second fluid being at least partially transverse with respect to the major longitudinal axis of the thermostatic mixing valve.
The present invention further relates to a mixing valve configured to produce a mixed fluid from the mixing of a first fluid and at least a second fluid. The mixing valve includes a valve body having a first fluid inlet, at least a second fluid inlet, and a fluid outlet, and at least one fluid inlet including a check valve configured to prevent fluid from flowing out of the valve through the at least one inlet. The check valve includes a first check valve member which is stationary within and with respect to the valve body, a second check valve member which is movable within the valve body in a defined path of motion and engageable with the first check valve member, and a biasing device for urging the second check valve member into engagement with the first check valve member and for defining the path of motion of the second check valve member.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a thermostatic mixing valve according to a preferred embodiment of the present invention.
FIG. 2 is an exploded perspective view of the thermostatic mixing valve of FIG. 1 .
FIG. 3 is a front sectional elevation view of the thermostatic mixing valve of FIG. 1 .
FIG. 3A is a fragmentary elevation view of the thermostatic mixing valve of FIG. 3 .
FIG. 4A is a front sectional elevation view of the thermostatic mixing valve of FIG. 1 showing full cold fluid flow and partial hot fluid flow.
FIG. 4B is a front sectional elevation view of the thermostatic mixing valve of FIG. 1 showing cold fluid flow.
FIG. 4C is a front sectional elevation view of the thermostatic mixing valve of FIG. 1 showing full flow of both hot fluid and cold fluid.
FIG. 4D is front sectional elevation view of the thermostatic mixing valve of FIG. 1 showing the thermostat having failed and flow of only cold fluid.
FIG. 5 is a front elevation view of the thermostatic mixing valve according to an alternative embodiment.
FIG. 6 is a left side elevation view of the thermostatic mixing valve of FIG. 5 .
FIG. 7 is a front sectional elevation view of the thermostatic mixing valve of FIG. 5
FIG. 7A is a fragmentary elevation view of the thermostatic mixing valve of FIG. 7 .
FIG. 8A is a front sectional elevation view of the thermostatic mixing valve of FIG. 5 showing flow of both hot fluid and cold fluid.
FIG. 8B is a front sectional elevation view of the thermostatic mixing valve of FIG. 5 showing flow of only cold fluid.
FIG. 8C is a front sectional elevation view of the thermostatic mixing valve of FIG. 5 showing flow of only hot fluid.
FIG. 8D is a front sectional elevation view of the thermostatic mixing valve of FIG. 5 showing the thermostat having failed and no fluid flow.
FIG. 9 is an exploded perspective view of the thermostatic mixing valve of FIG. 5 .
FIG. 10 is an exploded perspective view of a valve member of the thermostatic mixing valve of FIG. 5 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 through 4 show a thermostatic mixing valve according to a preferred embodiment for producing from a first fluid and a second fluid a mixed fluid substantially of a particular temperature which is intermediate the temperatures of the first fluid and the second fluid. The first fluid is higher in temperature than is the second fluid. For ease of understanding, the first fluid is sometimes referred to herein as a hot fluid and the second fluid as a cold fluid (though both may be “hot” or “cold” in terms of human sensory perception and they may be separated by only a relatively small temperature difference).
FIG. 1 shows a thermostatic mixing valve 102 having a valve body 104 , a cold fluid inlet port 110 associated with a cold fluid inlet designated by the reference letter “C”, a hot fluid inlet port 112 associated with a hot fluid inlet designated by the reference letter “H”, and a mixed fluid outlet port 114 associated with a mixed fluid outlet designated by the reference letter “M”. Thermostatic mixing valve 102 also includes a bonnet 116 , a cap 134 , and a cover screw 142 for limiting access to an adjusting screw 140 (shown in FIG. 2 ). Thermostatic mixing valve 102 further includes a first check valve 274 associated with hot fluid inlet H and a second check valve 274 associated with cold fluid inlet C, each check valve 274 including a check valve cap 276 in which is threadedly engaged a stem 286 .
FIG. 2 shows valve body 104 including cold fluid inlet port 110 , hot fluid inlet port 112 , and mixed fluid outlet port 114 . Ports 110 , 112 , and 114 are configured for the connecting and sealing of appropriate fluid conduits (e.g., using pipe threads) to valve body 104 . A check valve 274 is assembled to valve body 104 in association with each inlet port 110 and 112 . Check valve 274 includes a seat 284 , a plug 282 , a check valve cap 276 , a stem 286 , a cylindrical filter screen 279 , and a biasing spring 280 . Check valve cap 276 is provided with threads 294 for engagement with threaded aperture 296 within valve body 104 , and is sealed to valve body 104 with an annular seal 278 . Stem 286 is provided with threads 290 for engagement with a threaded aperture 292 centrally located within check valve cap 276 , and is sealed to check valve cap 276 by an annular seal 285 .
Valve body 104 further includes a cavity 106 for the receiving of a valve member 144 . Valve body 104 , valve cap 134 , adjusting screw 140 and cover screw 142 may be made of various materials. According to any particularly preferred embodiment, valve body 104 and valve cap 134 are cast of brass, gray iron, or ductile iron, and adjusting screw 140 and cover screw 142 are machined of brass, bronze, or stainless steel.
A liner 146 is configured generally as a hollow cylinder having a side wall 152 and a lower end closed by a bottom wall 150 (shown in FIG. 3 ). Liner 146 further includes at least one transversely oriented upper opening 154 and at least one transversely oriented lower opening 156 for flow of cold and hot fluids, respectively, through side wall 152 . A circumferential groove 158 within the outer surface of side wall 152 is provided for a seal 254 . A seat 170 is secured to the inner surface of bottom wall 150 of liner 146 by a screw 172 , for seating of a lower edge 180 of a side wall 178 of a shuttle 174 and of a biasing spring 188 .
The position of shuttle 174 is adjustable within liner 146 . The orientation of sliding movement of shuttle 174 within liner 146 of valve member 144 defines the major longitudinal axis of valve member 144 , and hence of thermostatic mixing valve 102 . The upper end of biasing spring 188 is transversely restrained (or piloted) by a lower end 198 of a spring pilot 190 having a generally cylindrical shape, and is longitudinally restrained by a flange 192 circumscribing the outer surface of spring pilot 190 . Flange 192 is shown in a hexagonal configuration to provide wrench flats 200 for threaded assembly to a shuttle 174 and to a relief spring holder 204 shown in FIGS. 4A to 4 D. An upper end of spring pilot 190 includes a cavity 194 for the receiving and remaining of the lower end of a relief spring 202 . An upper end of relief spring 202 , and a disc 212 for spreading the axial load of relief spring 202 upon a lower end of a thermostat 214 , is received and retained within a cavity 206 oriented within a lower end of relief spring holder 204 .
In assembly of valve member 144 , a first valve member subassembly 240 is made by inserting disc 212 into cavity 206 within the bottom of relief spring holder 204 , inserting a first end of relief spring 202 into cavity 206 and upon disc 212 placing shuttle 174 upon the bottom of relief spring holder 204 so that a second end of relief spring 202 projects through an opening 186 within the upper surface of shuttle 174 , inserting the second end of relief spring 202 into cavity 194 of spring pilot 190 , and using wrench flats 200 of spring pilot 190 to fully engage threads 196 of spring pilot 190 with mating threads 208 within cavity 206 of relief spring holder 204 . This secures relief spring holder 204 , disc 212 , relief spring 202 , shuttle 174 , and spring pilot 190 together, with the top surface of shuttle 174 and relief spring 202 being clamped between a top surface of cavity 206 of relief spring holder 204 and a bottom surface of cavity 194 of spring pilot 190 to form, first valve member subassembly 240 .
An insert 242 is provided with a seal 246 which is seated within a peripheral groove located near a lower end of insert 242 . As shown in FIGS. 3 and 4A through 4 D, insert 242 is inserted into an upper end of liner 146 during assembly of valve member 144 , and seal 246 separates cold fluid from hot fluid within valve member 144 . Insert 242 includes at least one opening 264 for passage of cold fluid, as shown in FIGS. 3 and 4A through 4 D Insert 242 is held in position within a lower portion of bonnet 116 by liner 146 , which clamps insert 242 when liner threads 160 are engaged with mating threads within an opening 128 of bonnet 116 .
Referring again to FIG. 2, seat 170 , screw 172 , seal 254 , insert 242 , and seal 246 are preassembled to liner 146 , after which biasing spring 188 and first subassembly 240 are placed within the open end of liner 146 . A stem 248 is loosely received within a bellows 222 (shown in FIGS. 4A through 4D) of thermostat 214 , whereupon thermostat 214 with stem 248 is inserted through an opening 210 in a top surface of relief spring holder 204 to bear upon disc 212 (contained within first subassembly 240 ).
Valve member 144 is installed to opening 128 in a lower end of bonnet 116 using mating threads 160 and 162 . A seal 270 seals stem 248 to an aperture 249 within valve cap 134 . A second valve member subassembly 250 is then formed by further assembling to bonnet 116 a seal 130 and a seal 132 , valve cap 134 with a seal 136 using threads 138 , adjusting screw 140 , and cover screw 142 . Assembly of the thermostatic mixing valve is then completed by installing second valve member subassembly 250 to cavity 106 of valve body 104 by engaging threads 118 of bonnet 116 with threads 126 within the opening to cavity 106 of valve body 104 .
FIG. 3 shows a plurality of chambers formed within valve body 104 and valve member 144 of the thermostatic mixing valve. A hot fluid chamber 230 is in communication with hot fluid inlet port 112 , and a cold fluid chamber 232 is in communication with cold fluid inlet port 110 . Both hot fluid chamber 230 and cold fluid chamber 232 are open to valve member 144 . An inner passage 120 of bonnet 116 includes a preliminary mixing chamber 236 , which is in communication with a main mixing chamber 238 , which is in turn in communication with a mixed fluid outlet chamber 234 , itself in communication with mixed fluid outlet port 114 . Inner passage 120 and an outer passage 122 of bonnet 116 are separated by an annular inner bonnet wall 266 (which is coupled at a fixed distance from an annular outer bonnet wall 268 by at least two webs 124 (three, or four, are included in any particularly preferred embodiment for structural rigidity) oriented radially within outer passage 122 , having a thickness sufficient to structurally couple inner bonnet wall 266 to outer bonnet wall 268 ). Webs 124 are configured with a streamlined cross section having its greater dimension oriented vertically, in order to minimize obstruction of flow of mixed fluid.
FIGS. 4A-D show a thermostatic control device shown as thermostat 214 having a thermostat housing 216 is installed within both preliminary mixing chamber 236 and main mixing chamber 238 , which provides a large heat flow area for thermal convection to, and thermal conduction through, the walls of thermostat housing 216 . According to a particularly preferred embodiment, thermostat housing 216 includes at least one thin wall made of a material having a high coefficient of thermal conductivity (e.g., a copper alloy) in order to provide a low thermal impedance to a thermally responsive material 226 contained within thermostat housing 216 . Thermally responsive material 226 has a large coefficient of thermal expansion, and therefore expands substantially upon increasing in temperature and contracts substantially upon decreasing in temperature. Expansion upon increase in temperature increases a force exerted upon bellows 222 located within thermostat housing 216 .
Various substances are known to those skilled in the art for use as thermally responsive material 226 . According to an embodiment particularly preferred for economy of manufacture, an acetone is used for a thermally responsive material. According to an alternative embodiment particularly preferred for high performance when economy is a less important factor, a halogenated fluorocarbon such as MS-782 Vertrel XF manufactured and distributed by Miller-Stephenson Chemical of Danbury, Conn. is used for a thermally responsive material.
Bellows 222 is constructed in a manner (e.g., using circumferentially corrugated metal) which causes it to be radially stiff but longitudinally flexible. Bellows 222 has a closed end 224 located within thermostat housing 216 , and an open end 220 which is secured to an open end 218 of thermostat housing 216 . The periphery of the opening in open end 220 of bellows 222 may be sealed to the open end of thermostat housing 216 to prevent loss of thermally responsive material 226 .
Stem 248 , of generally cylindrical shape and a diameter which is slightly smaller than is the minimum inside diameter of bellows 222 , is placed within bellows 222 through open end 220 . An increase in temperature of thermostat 214 , caused by an increase in temperature of the mixed fluid surrounding thermostat 214 , causes an expansion of thermally responsive material 226 filling the space between the inner surfaces of thermostat housing 216 and the outer surfaces of bellows 222 , increasing a longitudinally oriented control force exerted upon closed end 224 of bellows 222 and thereby upon stem 248 , in a direction which tends to extend stem 248 out of thermostat 214 , and to thereby increase the combined lengths of thermostat 214 and stem 248 .
Upwardly oriented movement of stem 248 is prevented by adjusting screw 140 within valve cap 134 , so that any motion which occurs will be of thermostat 214 pressing against either relief spring 202 through disk 212 within first subassembly 240 or of thermostat 214 and first assembly 240 pressing against biasing spring 188 . Relief spring 202 is stiffer (i.e., has a higher spring rate) than is biasing spring 188 , so extension of stem 248 out of thermostat 214 results in a displacement of thermostat 214 vertically downward and an increase in compression of biasing spring 188 , the compressive force of biasing spring 188 balancing the force caused by the expansion of thermally responsive material 226 within thermostat 214 . Shuttle 174 is thereby displaced downwardly within liner 146 , decreasing open area associated with a hot fluid metering gap 258 of lower opening 156 and consequently flow rate of the hot fluid.
The setpoint temperature to which thermostat 214 controls is primarily a function or properties of thermally responsive material 226 and force of biasing spring 188 , which is influenced by the position of adjusting screw 140 . In any particularly preferred embodiment, such design parameters of the valve are selected by the valve designer and manufacturer so that, in normal operation of the valve using hot and cold fluid sources of typical pressures and temperatures, a desired mixed fluid outlet temperature can be obtained with adjusting screw 140 at or near the center of its range of screw thread travel. When adjusting screw 140 is rotated in a clockwise direction (assuming a right hand thread) to a position farther within valve cap 134 , it decreases the setpoint temperature by reducing the open area of lower openings 156 and thereby the flow rate of the hot fluid. Conversely, rotating adjusting screw 140 is an opposite direction to a position nearer the top of valve cap 134 similarly increases the setpoint temperature. Unauthorized tampering with adjusting screw 140 is discouraged by concealing adjusting screw 140 beneath a cover screw 142 .
Shuttle 174 and liner 146 thus cooperate to function as a hot fluid metering valve element. Because of the large diameter of the liner, wherein are located flow control openings 156 , relative to diameters of flow control openings of the poppet, plug, or globe types of valve element used in thermostatic control valves prior to the present invention, the cumulative open area of lower openings 156 is larger than is the open area of a comparably normally sized metering valve of the poppet, plug, or globe types, allowing a greater amount of flow at any given pressure drop trough thermostatic mixing valve 102 . A small change in position of shuttle 174 with respect to liner 146 in a preferred embodiment correspondingly results in a comparably greater change in flow rate of hot fluid than does a similar change in position of a hot fluid flow metering element in a thermostatic mixing valve of the poppet, plug, or globe type.
According to a particularly preferred embodiment (by way of example and not of limitation), of a thermostatic mixing valve, ports 110 and 112 are of 1 inch nominal pipe size and 114 is of 1¼ inch normal pipe size. Liner 146 is of approximately 1.491/1.492 inch inside diameter. Two lower openings 156 within the wall of liner 146 are spaced approximately 0.48 inch from two upper openings 154 . Each opening 154 , 156 is configured as a slot cut through the wall of liner 146 , subtends an angle of approximately 145 degrees, and is approximately 0.13 inch in height, for hot and cold fluid flow areas at liner 146 of approximately 0.49 square inch, respectively. Testing of the thermostatic mixing valve using hot tap water of approximately 160 degrees Fahrenheit (F) and cold tap water of approximately 55 degrees F. produced the results shown in TABLE 1 below with a valve shuttle and stem stroked manually and controllably. The term “C v ” is a measure of valve flow capacity at a given pressure drop across a valve and is often from the relationship Q=C v *(Δp) ½ , wherein “Q” designates flow rate in U.S. gallons per minute (gpm) and “Δp” designates pressure drop in pounds per square inch (psi).
TABLE 1
Valve
Shuttle And
Hot Water
Cold Water
Cold
Flow
Stem Stroke
Flow Rate
Hot Water
Flow Rate
Water
Capacity
(inches)
(gpm)
Δp (psi)
(gpm)
Δp (psi)
(Total C v )
0
4.9
55
51.0
20
12.0
0.0093
11.1
55
48.4
20
12.3
0.0186
16.6
52
47.1
22
12.3
0.0279
22.7
42
44.5
24
12.6
0.0372
27.1
35
42.1
26
12.7
0.0465
28.2
30
40.6
28
12.8
0.0558
30.5
25
38.6
30
13.1
0.0651
31.7
21
34.9
33
13.0
0.0744
23.9
20
31.1
35
12.8
0.0837
35.9
16
29.3
40
12.7
0.0930
36.2
14
19.8
45
12.6
0.1023
36.5
11
13.3
50
12.8
The direction of movement of shuttle 174 within liner 146 is perpendicular to that of the fluid being metered, the fluid therefore not exerting a stagnation or velocity pressure against the face of shuttle 174 as it does against the flow control element of a poppet, plug, or globe valve. This enables control of higher flow rates at higher velocities and pressures using a smaller thermostat than is possible with thermostatic valve of the previously used poppet, plug, or globe types. Liner 146 is closed at its bottom end by a bottom wall 150 but has an opening 148 at its upper end, allowing the hot fluid to flow upwardly through the interior of shuttle 174 and passages 182 of shuttle 174 . Passages 182 are formed by a displacement of a top portion 184 of shuttle 174 from side wall 178 of shuttle 174 , top portion 184 being held in fixed relationship to side wall 178 by a web 176 of shuttle 174 .
FIG. 3 shows check valve 274 in an installed and operating condition (see FIG. 2 for exploded view). Spring 280 holds plug 282 against seat 284 in an absence of flow of mixed fluid from mixed fluid outlet M. fluid pressures being equal on both sides of plug 282 when there is no flow. When mixed fluid M is desired and flow is allowed from mixed fluid outlet M, back pressure drops on the downstream side of plug 282 and inlet supply pressure forces plug 282 upward, compressing spring 280 by a distance corresponding to the pressure difference across plug 282 . Spring 280 is configured to have a high lateral stiffness, so that it may not only serve to urge plug 282 against seat 284 but may also guide plug 282 in its path of motion between the opened and closed states of check valve 274 .
FIG. 3A is a detail of a portion of check valve 274 shown in FIGS. 2 and 3. Stem 286 is provided a tip 286 a of a particular size and shape, and plug 282 is provided a recess 288 which coats with tip 286 a . These are included to maintain the position of plug 282 centrally located within check valve 274 during conditions of high flow rate and correspondingly high fluid velocity, when plug 282 is forced fully upward and plug 282 , with the associated end of spring 280 , may otherwise be dragged toward the center of thermostatic mixing valve 102 by drag of the high-velocity fluid. (Check valve 274 may also include other associated seals (such as annular seal 283 ) and washers.) For configuring of check valves 274 for operation of thermostatic mixing valve 102 , the position of threaded stem 286 within check valve cap 276 is adjusted upwardly as shown to provide plug 282 room to move upward. For service or maintenance of thermostatic mixing valve 102 , stem 286 may be turned to advance it downwardly and thereby force plug 282 against seat 284 and close off the associated inlet of thermostatic mixing valve 102 .
FIGS. 4A, 4 B, 4 C, and 4 D illustrate the operation of thermostatic mixing valve 102 in various conditions of operation.
FIG. 4A shows thermostatic mixing valve 102 in normal operation, with shuttle 174 intermediately oriented within liner 146 . Cold fluid from cold fluid inlet port 110 flows, through upper opening 154 of liner 146 and into preliminary mixing chamber 236 , and hot fluid from hot fluid inlet port 112 flows through lower opening 156 of liner 146 and through an at least one passage 182 of shuttle 174 into preliminary mixing chamber 236 . Mixing of the hot and cold fluids begins prior to flowing into preliminary mixing chamber 236 , continues in preliminary mixing chamber 236 , and is completed within main mixing chamber 238 . Thermostat 214 is immersed in the mixed fluid at a particular temperature within main mixing chamber 238 , and thermally responsive material 226 is at substantially the same temperature due to the effects of heat transfer (thermal conduction and convection) at the wall of thermostat housing 216 . Thermally responsive material 226 within thermostat housing 216 , and therefore bellows 222 , are neither fully contracted nor fully expanded, nor is biasing spring 188 fully extended or fully contracted.
In normal operation, the temperature of the mixed fluid is controlled by the longitudinal position of shuttle 174 within and with respect to liner 146 , which is in turn controlled by the corresponding specific volume of thermally responsive material 226 at that temperature and by the opposing force of biasing spring 188 , the latter corresponding to the position of adjusting screw 140 . The open area of a hot fluid metering gap 258 at lower openings 156 , and thereby the rate of flow through them, is metered by the longitudinal position of shuttle 174 and thereby by the amount that the side wall 178 of shuttle 174 overlaps and covers lower openings 156 . The flow of hot fluid continues in an upwardly oriented direction into preliminary mixing chamber 236 . Hot fluid is kept separated from cold fluid before leaving upper openings 154 and lower opening 156 of liner 146 by a shuttle seal 168 oriented within a peripherally oriented groove within side wall 178 of shuttle 174 .
Cold fluid similarly enters valve body 104 through cold fluid inlet port 110 and fills cold fluid inlet chamber 232 . Cold fluid then flows through transversely oriented openings, shown as upper openings 154 , which penetrate the wall of liner 146 , and immediately thereafter through similarly oriented transverse openings 264 penetrating a wall of insert 242 . Cold fluid then flows upwardly, meeting and mixing with hot fluid. The at least partially mixed fluid proceeds upwardly through preliminary mixing chamber 236 within bonnet inner passage 120 into main mixing chamber 238 , flowing over the surface of thermostat housing 216 of thermostat 214 as it does so and thereby maintaining thermally responsive material 226 within thermostat housing 216 at a temperature substantially equal to that of the mixed fluid. Mixed fluid then flows downwardly through an outer bonnet passage 122 into a mixed fluid outlet chamber 234 , from which it exits the thermostatic mixing valve through mixed fluid outlet port 114 .
FIG. 4B shows a condition of operation in which the mixed fluid has become too hot (e.g., caused by a large increase in temperature or supply pressure of the hot fluid) and thermally responsive material 226 has therefore expanded. This has forced thermostat 214 , and thereby lower edge 180 of side wall 178 of shuttle 174 , downward onto seat 170 , completely covering lower openings 156 to decrease the hot fluid metering gap to substantially zero and substantially stopping flow of hot fluid. Because lower edge 180 is now abutting seat 170 , biasing spring 188 can be compressed no farther. To prevent thermostat housing 216 and/or bellows 222 from rupturing due to excessive expansion of thermally responsive material 226 caused by excessively high temperature of the mixed fluid, relief spring 202 allows additional extension of stem 248 from thermostat 214 by compressing in response to the expansion of thermally responsive material 226 , thus relieving excessive force otherwise exerted by thermally responsive material 226 .
FIG. 4C shows a condition of operation in which the temperature of the mixed fluid has become too cold (e.g., caused by a large reduction in temperature and/or supply pressure of the hot fluid). Thermally responsive material 226 has cooled in response to the reduced temperature of the mixed fluid surrounding thermostat 214 , and has contracted and has reduced the force it exerts upon biasing spring 188 through thermostat 214 and first assembly 240 . This allows biasing spring 188 to lift first subassembly 240 and thermostat 214 , maintaining the abutting relationship between stem 248 and adjusting screw 140 . Shuttle 174 is a member of first subassembly 240 , and is therefore lifted with it, increasing the hot fluid metering gap of lower openings 156 fully. Hot fluid flow rate thereby increases and relieves the excessively cold condition of the mixed fluid, bringing valve member 144 back into equilibrium.
FIG. 4D shows an abnormal condition of operation which is encountered when thermostat 214 fails to function, in the illustrated instance due to leakage of thermally responsive material 226 through a rupture in bellows 222 . Since thermostat 214 is now unable to retain thermally responsive material 226 within housing 216 , spring 188 forces thermostat 214 and first subassembly 240 upward until stopped by abutting of a top surface of top portion 184 of shuttle 174 upon a lower surface, or an auxiliary seat 260 , of insert 242 . Although this fully opens lower openings 156 for maximum flow rate of hot fluid, the abutting of shuttle 174 top portion 184 upon auxiliary seat 260 constitutes closure of a backup shutoff valve 272 and prevents hot fluid from flowing beyond shuttle 174 into preliminary mixing chamber 236 . Cold fluid, however, continues to flow unimpended and unabated. Therefore, a failure of thermostat 214 results in a condition of an emergency shower bath remaining available (with cold fluid only) in spite of a failure of thermostat 214 .
FIGS. 5 through 10 show an alternative embodiment of the thermostatic mixing valve for the producing of a mixed fluid of a particular temperature from a cold fluid and a hot fluid, wherein all flow (i.e., flow of the cold fluid, the hot fluid, and mixed fluid) is stopped upon failure of the thermostatic control device (e.g., shown as a device which changes in length upon a change in temperature of a fluid in which the device is at least partially immersed).
FIGS. 5 and 6 show the alternative embodiment of a thermostatic mixing valve 302 including a valve body 304 having a cold fluid inlet port 310 and a hot fluid inlet port 312 (given reference letters C and H, respectively) and a single mixed fluid outlet port 314 (given a reference letter M). Ports 312 , 310 , and 314 are configured for sealably connecting fluid conduits (e.g., using pipe threads). A valve cap 334 is mounted upon the top of valve body 304 , and holds an adjusting screw 340 and a cover screw 342 , both shown in FIG. 7 . Thermostatic mixing valve 302 further includes a first check valve 474 associated with hot fluid inlet H and a second check valve 474 associated with cold fluid inlet C, each check valve 474 including a check valve cap 476 in which is threadedly engaged a stem 486 .
Valve body 304 , valve cap 334 , adjusting screw 340 , and cover screw 342 may be made of various materials. According to any preferred embodiment, valve body 304 and valve cap 334 are cast of brass, gray iron, or ductile iron, and adjusting screw 340 and cover screw 342 are machined of brass, bronze, or stainless steel.
FIG. 7 shows valve body 304 , valve cap 334 , a thermostat 414 , thermostat adjusting screw 340 and cover screw 342 , a cold fluid inlet chamber 432 and a hot fluid inlet chamber 430 , a main mixing chamber 438 , and a fluid flow control element shown as a valve member 344 . Hot fluid inlet port 312 and cold fluid inlet port 310 are oriented near the right and left sides of the valve respectively, and mixed fluid outlet port 314 is located at the bottom of valve body 304 and is open to a mixed fluid chamber 434 . Valve body 304 further includes a cavity 306 , open at its top for the receiving of a valve member 344 .
A check valve (shown as check valve 474 ) is assembled to valve body 304 in association with each inlet port 310 and 312 . Check valve 474 includes a seal 484 , a plug 482 , check valve cap 476 , a stem 486 , a cylindrical filter screen 479 (with a centering taper), and a biasing spring 480 . Check valve cap 476 is provided with threads 494 for engagement with a threaded aperture 496 within valve body 304 , and is sealed to valve body 304 with an annular seal 478 . Stem 486 is provided with threads 490 for engagement with a threaded aperture 492 centrally located within check valve cap 476 , and is sealed to check valve cap 476 by an angular seal 485 . Spring 480 holds plug 482 against seat 484 in an absence of flow of mixed fluid from mixed fluid outlet M, fluid pressures being equal on both sides of plug 482 (which may have a tapering shape and may be provided with one or more annular seals) when there is no flow. When mixed fluid M is desired and flow is allowed from mixed fluid outlet M, back pressure drops on the downstream side of plug 482 and inlet supply pressure forces plug 482 downward, compressing spring 480 by a distance corresponding to the pressure a difference across plug 482 . Spring 480 is configured to have a high lateral stiffness, so that it may not only serve to urge plug 482 against seat 484 but may also guide plug 482 in its path of motion between the opened and closed states of check valve 474 .
FIG. 7A is a detail of a portion of check valve 474 shown in FIG. 7 . Biasing spring 480 is a compression coil spring, and is engaged with check valve cap 476 by a special thread 481 upon check valve cap 476 having a thread form, pitch, and pitch diameter matching the configuration of biasing spring 480 . Biasing spring 480 is similarly engaged with plug 482 by a similar thread 471 . For configuring of check valves 474 for operation of thermostatic mixing valve 302 , the position of threaded stem 486 within check valve cap 476 is adjusted downwardly as shown to provide plug 482 room to move downward. For service or maintenance of thermostatic mixing valve 302 , stem 486 may be turned to advance it upwardly and thereby force plug 482 against seat 484 and close off the associated inlet of thermostatic mixing valve 302 .
Valve body 304 is divided into various chambers including a main mixing chamber 438 (of an annular shape, oriented below valve cap 334 ), a cold fluid chamber 432 (of an annular shape, and in communication with cold fluid inlet port 310 ), a hot fluid chamber 430 (of an annular shape, and in communication with hot fluid inlet port 312 ), and mixed fluid outlet chamber 434 in communication with mixed fluid outlet port 314 . Valve member 344 is installed within cavity 306 of valve body 304 and is secured within valve body 304 by engagement of a screw thread 360 upon valve member 344 with a screw thread 308 within cavity 306 . A preliminary mixing chamber 436 (also shown in FIG. 8) is contained within valve member 344 , as is a shuttle 374 for modulating flows of hot and cold fluid (shown in FIGS. 8 and 10 ).
Referring to FIG. 9, which is a partially exploded view of thermostatic mixing valve 302 valve body 304 is shown with valve member 344 and valve cap 334 . Valve member 344 is generally cylindrical in shape and is installed with generally cylindrical valve body cavity 306 inside of valve body 304 . A threaded portion 360 of a liner 346 of valve member 344 is engaged with a lower threaded bore 308 within cavity 306 to secure valve member 344 within valve body 304 . An upper liner seal 452 and a lower liner seal 454 prevent leakage. Valve cap 334 has a headed portion 338 that is threaded into an upper threaded bore 326 of valve body 304 to secure valve cap 334 to valve body 304 and to close valve body cavity 306 . Valve cap 334 holds adjusting screw 340 , the position of which is secured against tampering by cover screw 342 . Adjusting screw 340 and cover screw 342 are engaged with screw threads located within an upper area of an aperture 427 extending through valve cap 334 , and an upper portion of thermostat 414 is installed with a lower portion of aperture 427 so that it bears upon the bottom of adjusting screw 340 . A seal 428 seals thermostat 414 to aperture 427 within valve cap 334 , while a seal 336 seals valve cap 334 to valve body 304 .
Valve member 344 includes cylindrical liner 346 and thermostat 414 having a cylindrical thermostat housing 416 that is at least partially received within the interior of valve cap 334 when valve cap 334 is threaded onto valve body 304 . Valve member 344 further includes a top flange 364 which includes a hub 362 (shown with a hexagonal shape to facilitate installation with a wrench) having a central circular opening 348 within which thermostat housing 416 freely slides. Cylindrical liner 346 of valve member 344 includes two sets of circumferentially oriented openings (shown as upper openings 354 and lower openings 356 ) which form passages though a side wall 352 of liner 346 .
Valve member 344 is shown in an exploded view of FIG. 10 so that the relationship of its elements may be more clearly described.
Thermostat 4 , having a thermostat housing 416 , is installed within both preliminary mixing chamber 436 and main mixing chamber 438 . According to a particularly preferred embodiment, thermostat housing 416 includes at least one thin wall made of a material having a high coefficient of thermal conductivity (e.g., a copper alloy) in order to provide a low thermal impedance from the mixed fluid to a thermally responsive material 226 (e.g. acetone) contained within thermostat housing 416 and thereby shorten response time of thermostatic mixing valve 302 . Thermally responsive material 226 has a large coefficient of thermal expansion, and therefore expands substantially upon increasing in temperature and contracts substantially upon decreasing in temperature. Expansion of thermally responsive material 226 within thermostat housing 416 upon an increase in temperature increases a force exerted upon bellows 422 located within thermostat housing 416 .
Bellows 422 is constructed in a manner (e.g., using circumferentially corrugated metal) which causes it to be radially stiff but longitudinally flexible. Bellows 422 is hollow and has a first end 424 which is closed and located within thermostat housing 416 , and a second end 420 which is open and secured to an open end 418 of thermostat housing 416 . Bellows 422 is installed to an open end 418 of housing 416 and is sealed thereto by a seal 462 . A valve stem 448 (e.g., a cylindrical rod) extends through an opening in a second end 420 and into bellows 422 so that the upper end of stem 448 bears upon the inner surface of the first end 424 of bellows 422 , and is maintained in this bearing relationship by a compressive coil biasing spring 388 pressing upon the lower end of stem 448 through a transversely oriented web 376 of shuttle 374 , a relief spring 402 , and a disc 412 . Shuttle 374 , having a cylindrical shape, is slidably received within liner 346 and is provided a seal 368 for sealing cold fluid from hot fluid. The orientation of sliding movement of shuttle 374 and of stem 448 defines the major longitudinal axis of valve 4 member 344 , and hence of thermostatic mixing valve 302 . Shuttle 374 includes a side wall 378 and a spring pilot portion 390 . Side wall 378 is joined to spring pilot portion 390 by a transversely oriented and ring-shaped web 376 having at least one passage 382 through which fluid flows in an axial direction. Spring pilot portion 390 of shuttle 374 has a closed bottom 398 and an open top with a threaded bore (visible in FIG. 8) which is used to assemble a top portion 384 of shuttle 374 , a relief spring 402 being retained within a relief spring holder 404 , configured as a cavity within spring pilot 390 , by top portion 384 of shuttle 374 . As shown in FIGS. 8 and 10, an annular space 391 exists between an outer surface of spring pilot portion 390 and an inner surface of side wall 378 of shuttle 374 .
Thermally responsive material 226 , expanding or contracting within thermostat housing 416 generally in correspondence to an increase or decrease respectively in temperature of the mixed fluid surrounding thermostat housing 416 , causes bellows 422 to contract and expand correspondingly and respectively, in opposition to biasing spring 388 . Stem 448 , in contact with bellows 422 , is thereby moved to correspondingly adjust (longitudinal position of shuttle 374 , which is coupled to stem 448 , within liner 346 and to thereby proportionally regulate the sectional flow areas of a cold fluid metering gap 456 and a hot fluid metering gap 458 , and thereby the temperature of the mixed fluid. Adjusting screw 340 changes the force exerted by biasing spring 388 by shifting position of the group of parts including thermostat 414 , stem 448 , shuttle 374 , disc 412 , and relief spring 402 , thereby adjusting temperature of the mixed fluid within main mixing chamber 438 at which shuttle 374 reaches a particular position within liner 346 .
The setpoint temperature, or temperature to which thermostat 414 controls is primarily a function of properties of thermally responsive material 226 and force of biasing spring 388 , which is influenced by the position of adjusting screw 340 . In any preferred embodiment, such design parameters of the valve are selected by the valve designer and manufacturer so that, in normal operation of the valve using hot and cold fluid sources of typical pressures and temperatures, a desired mixed fluid outlet temperature can be obtained with adjusting, screw 340 at or near the center of its range of screw thread travel. When adjusting screw 340 is rotated in a clockwise direction (assuming a right-hand thread) to a position farther within valve cap 334 , it decreases the setpoint temperature by reducing the open area or lower openings 356 and thereby the flow rate of the hot fluid. Conversely, rotating adjusting screw 340 in an opposite direction to a position nearer the top of valve cap 334 similarly increases the setpoint temperature. Concealing adjusting screw 340 beneath a cover screw 342 discourages unauthorized tampering with adjusting screw 340 .
Shuttle 374 and liner 346 thus cooperate to function as a fluid metering valve element. Because of the large diameter of the liner, wherein are located flow control openings 356 , relative to diameters of flow control openings of the poppet, plug, or globe types of valve element, the cumulative open area of lower openings 356 is larger than is the open area of a comparably nominally sized metering valve of the poppet, plug, or globe types, allowing a greater amount of flow at any given pressure drop through thermostatic mixing valve 302 . A small change in position of shuttle 374 with respect to liner 346 in any preferred embodiment correspondingly results in a comparably greater change in flow rate of hot fluid than does a similar change in position of a hot fluid flow metering element in a thermostatic mixing valve of the poppet, plug, or globe type.
The direction of movement of shuttle 374 within liner 346 is perpendicular to that of the fluid being metered, the fluid thereby not exerting a stagnation or velocity pressure against the face of shuttle 374 as it does against the flow control element of a poppet, plug, or globe valve. This enables control of higher flow rates at higher velocities and pressures using a smaller thermostatic than is possible with thermostatic valve of the previously used poppet, plug, or globe types.
Valve member 344 includes a top shuttle portion 384 having a central circular opening 386 . Valve stem 448 is inserted at its lower end through opening 386 and abuts disc 412 , which provides an enlarged area upon which relief spring 402 bears. Disc 412 and relief spring 402 are installed within spring pilot portion 390 of shuttle 374 , and are secured therein by top portion 384 of shuttle 374 when it is installed to spring pilot 390 portion by, e.g., screw threads. The lower end of valve stem 448 extends slidably through the central circular opening 386 within top portion 384 , and is maintained in contact with disc 412 by biasing spring 388 .
Liner 346 is provided a bottom wall 350 , which is configured as a separate part although it may alternatively be made integral with liner 346 . As shown, bottom wall 350 is a threaded plug having a central interior recess 366 for searing of biasing spring 388 . Bottom wall 350 also includes a seat 370 for seating of a bottom edge 380 of outer wall 378 of shuttle 374 . Biasing spring 388 is seared at its upper end upon ring-shaped web 376 and around the perimeter of spring pilot 390 portion of shuttle 374 .
Operation of thermostatic mixing valve 302 is described below in reference to FIGS. 8A through 8D.
FIG. 8A shows thermostatic mixing valve 302 in normal operation, with to shuttle 374 intermediately oriented within liner 346 . Cold fluid from cold fluid inlet port 310 flows through upper openings 354 within side wall 352 of liner 346 , and hot fluid from hot fluid inlet port 312 flows through lower openings 356 within side wall 352 of liner 346 and through passages 382 of shuttle 374 . Mixing of the hot and cold fluids begins immediately, continues in preliminary mixing chamber 436 , and is completed as the at least partially mixed fluids enter main mixing chamber 438 Thermostat 414 is immersed in the mixed fluid at a particular temperature within main mixing chamber 438 , and thermally responsive material 226 is at substantially the same temperature due to thermal convection at the wall of housing 416 and thermal conduction through the wall of housing 416 . Thermally responsive material 226 within thermostat housing 416 , and therefore bellows 422 , are neither fully contracted nor fully expanded, nor is biasing spring 388 fully contracted or fully extended. In normal operation, the temperature of the mixed fluid is controlled by axial position of shuttle 374 within and with respect to liner 346 , which is in turn controlled by the corresponding specific volume of thermally responsive material 226 at that temperature and by the opposing force of biasing spring 388 , the latter corresponding to the position of adjusting screw 340 .
In FIG. 8B, the valve is shown compensating for a hot outlet fluid condition (with respect to the temperature setting). Shuttle 374 is oriented fully downward (at the end of its normal axial path of travel) within liner 346 because thermally responsive material 226 has expanded and bellows 422 has therefore contracted, thereby moving shuttle 374 downwardly.
Were the mixed fluid to be still hotter, thermally responsive material 226 would attempt to expand further and, if stem 448 were blocked against further movement downward, thermally responsive material 226 could expand to the point that damage could result to housing 416 , bellows 422 , or the junction of bellows 422 with housing 416 . To prevent this from happening, relief spring 402 provides for additional movement of stem 448 when shuttle 374 is blocked by seat 370 of bottom wall 350 against further movement, thereby relieving force otherwise caused by excessive expansion of thermally responsive material 226 . Lower openings 356 within side wall 352 of liner 346 are closed, blocked by side wall 378 of shuttle 374 . The bottom edge 380 of side wall 378 of shuttle 374 rests against the top of seat 370 of bottom wall 350 , and side wall 378 of shuttle 374 closes lower openings 356 , reducing hot fluid metering gap 458 to substantially zero which substantially prevents the flow of hot fluid into preliminary mixing chamber 436 . Cold fluid flows through upper openings 354 of liner 346 and into preliminary mixing chamber 436 (above shuttle 374 ). The temperature of the mixed fluid in main mixing chamber 438 thus decreases because the flow from cold fluid inlet chamber 432 is in greater proportion of the total flow than it had been. As the temperature of the mixed fluid decreases, causing thermally responsive material 226 to contract, bellows 422 expands, readjusting the position of shuttle 374 and bringing the temperature of the mixed fluid into an equilibrium condition with respect to the temperature setting of the valve.
In FIG. 8C, the valve is shown compensating for a cold fluid condition (with respect to the temperature setting of the valve). Shuttle 374 is oriented upwardly (at the end of its normal axial path of travel as constrained by valve stem 448 within bellows 422 ) within liner 346 because thermally responsive material 226 has contracted, allowing bellows 422 to expand and thereby allowing biasing spring 388 to expand (within a constrained axial path of travel defined by valve stem 448 within bellows 422 of thermostat 414 ). Upper openings 354 of liner 346 are closed, blocked by side wall 378 of shuttle 374 , which reduces cold fluid metering gap 456 to substantially zero and thereby substantially prevents the flow of cold fluid into preliminary mixing chamber 436 . Hot fluid flows through lower openings 356 of liner 346 and into preliminary mixing chamber 436 (through passages 382 within shuttle 374 ). The temperature of the mixed fluid in main in a chamber 438 thus increases because the flow from hot fluid chamber 430 is in greater proportion of the total flow than it had been. Bellows 422 thereafter contracts as the temperature of the mixed fluid, and of thermally responsive material 226 , increases, readjusting the position of shuttle 374 and thereby bringing the temperature of the mixed fluid into an equilibrium condition with respect to the temperature setting of the valve.
In FIG. 8D thermostatic mixing valve 302 is shown in a failure condition caused by rupture of bellows 422 within thermostat housing 416 . Biasing spring 388 has fully expanded (no longer constrained by bellows 422 , see FIG. 8 C), driving shuttle 374 upward and thereby forcing disc 412 into valve stem 448 and driving top portion 384 of shuttle 374 fully upward into an auxiliary seat 460 , effectively forming a backup shutoff valve 472 within thermostatic mixing valve 302 . While hot fluid flows through lower openings 356 of liner 346 and through at least one shuttle passage 382 up into preliminary mixing chamber 436 , it is prevented from flowing beyond preliminary mixing chamber 436 and into main mixing chamber 438 by the engagement of upper portion 384 with auxiliary seat 460 . Moreover, upper openings 354 of liner 346 are blocked by side wall 378 of shuttle 374 to shut off flow of cold fluid. The seating of top portion 384 upon auxiliary seat 460 blocks all flow from preliminary mixing chamber 436 to main mixing chamber 438 by biasing spring 388 Consequently, no fluid (hot, cold, or mixed) flows through outlet port 314 .
As shown in the embodiments of FIGS. 1-3 and 5 - 7 , valve body 104 , 304 includes a third fluid inlet 510 positioned between the check valve seat 284 , 484 and the mixed fluid outlet port 114 , 314 . Illustratively, the third fluid inlet port 510 is between cold fluid inlet port 110 , 310 and the mixed fluid outlet port 114 , 314 . Further illustratively, in the embodiment of FIG. 3, third fluid inlet 510 is adjacent plug 282 . As shown in FIGS. 3 and 7, third fluid inlet 510 is illustratively between the mixing chamber 238 , 438 and check valve seat 284 , 484 .
Although only a few exemplary embodiments for the present invention have been described in detail, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. For example, valve caps may be secured to valve bodies by machine screws; bellows nay be brazed or soldered to thermostat housing wails or bases to form substantially hermetic seals. Accordingly, all such modifications are intended to be included within the scope of the invention as defined in the following claims. In the claims, each means-plus-function clause is intended to cover the structures described herein as performing the recited function, and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes, and omissions may be made in the designs, operating conditions, and arrangements of the preferred embodiments without departing from the spirit of the invention as expressed in the appended claims. | Check valves for use in fluid conducting structures such as thermostatic mixing valves are provided. Illustratively, the fluid conducting structure provides a passageway defining an axis, and the check valve comprises a cap coupled to the structure, a seat disposed in the passageway and spaced apart from the cap, a valve member axially movable between a sealed position engaging the seat and an opened position spaced apart from the seat, and a spring urging the valve member to engage the seat, the spring being coupled to the valve member and the cap. | 8 |
BACKGROUND OF THE INVENTION
Prior Portable Power Distribution Vest Systems
[0001] Excess weight from unused batteries and other supplies has become a critical problem in mobility of a person carrying a large number of electronics and other materials over great distances. Having to move quickly and easily, while having to wear and/or carry all the material for extended periods has proven to be a burden for field personnel. This problem has become further exasperated by having many different battery types and many different power requirements.
[0002] As described in the article “Researchers Tackle Marines' Portable Power Challenges”, May 2011, National Defense, NDIA's Business and Technology Magazine, by Grace V. Jean, a key problem is needing to carry batteries for each specialized device, but not being able to use all of the batteries for other specialized devices because the batteries for the other devices are not the same. This introduces two problems: if a device uses up all the batteries of one type a user has in possession and other incompatible batteries cannot be used, then these unused batteries not only become excess weight, but also become unutilized energy sources due to carrying incompatible batteries.
[0003] The modern soldier, police officer, or firefighter, carrying heterogeneous electronics and other safety/warfare equipment with different power supply needs faces unnecessary challenges of this excess weight of batteries. Incompatible battery equipment, having to carry excess unused spare batteries and chargers after completing a mission all exemplifies the critical need to have a clear ideal standard for a highly reliable, light-weight, wearable, optimized power distribution and charging system. Many different battery types are currently being used instead of having one standard type. Only a small standard set of power parameters is all that is needed so that the system can utilize the maximum energy density per unit of mass the user carries. End device loads can adjust the voltage to fit their specialized application through converters or pin setting.
[0004] Most efficient light weight portable power distribution systems are designed for avionic, spacecraft, ships, automobiles, or other vessels through many years of quality engineering effort in weight efficiency; however none of these have been known to be effectively applied to a wearable vest.
U.S. Patents
[0005]
[0000]
Patent Number
Kind Code
Issue Date
Patentee
7,872,444
B2
2011 Jan. 18
Symbol Technologies,
Inc.
7,863,859
—
2011 Jan. 04
Cynetic Designs Ltd.
7,411,337
—
2008 Aug. 12
Intel Corporation
7,221,552
B1
2007 May 22
Brown
7,150,938
—
2006 Dec. 19
Munshi
6,915,641
—
2006 Dec. 19
Lithium Power
Technologies, Inc.
6,899,539
—
2005 May 31
Exponent Inc.
5,806,740
—
1998 Sep. 15
Raytheon Company
5,572,401
—
1996 Nov. 05
Key Idea Development,
L.L.C.
U.S. Patent Application Publications
[0006]
[0000]
Application Number
Kind Code
File Date
Patentee
20110089894
A1
2011 Apr. 21
Soar; Roger J.
20110018498
A1
2011 Jan. 27
Soar; Roger J.
20110031928
A1
2010 Oct. 13
Soar; Roger J.
20110018498
A1
2010 Sep. 29
Soar; Roger J.
FOREIGN PATENT DOCUMENTS
Nonpatent Literature Documents
[0000]
“Researchers Tackle Marines' Portable Power Challenges”; May 2011; Jean, Grace V.; National Defense: NDIA's Business and Technology Magazine
SUMMARY OF THE INVENTION
[0008] A network of standard intelligent interconnected modules whereby health of the module, as well as the supply status of the module is monitored and communicated. The health monitoring data is used to allocate and share flows of critical supplies to and from modules in need, based on module criticality, and to provide supply flows in a prioritized manner.
[0009] The intelligent networked module includes an improved light weight wearable vest or suite (referred to as vest) that contains a standardized, highly reliable as well as interchangeable switchable mesh of supply, data distribution, & supplying systems that are integrated into a comfortable and light weight system such that if portions are destroyed by gunfire, explosives or other failures do not easily take down the entire system or critical elements within the system.
[0010] The improved vest modular system provides maximum utilization and reliability per unit weight of supply storage by automatically disconnecting and bypassing failed system modules, as well as automatically recovering system modules. System modules are standardized and prioritized such that they easily are added and removed with automatic configuration and recognition with manual override capability. All the supply sources and supply storage is standardized such that all supplies and supply sources contribute to the supplying of all functional modules with priority set on criticality level of modules, similar to that designed for criticality levels of avionics systems (e.g. Level A most critical, Level B critical, Level C less critical, Level D non-critical, and Level E least critical system).
[0011] Different common standardized voltage levels can be achieved on the same pin using Direct Current (DC) to DC converters. The different voltages can be provided on the same standard plug by setting different pin configurations such as shorting a pin or pins to a common ground thereby changing the pin voltage levels to established set standard levels.
[0012] For military or other applications, to improve energy efficiency per unit of mass carried the weight of bullet heads can be used for dual purpose as both projectiles as well as a battery that can be designed to survive bodily impact intact.
[0013] Energy recovery systems, such as a weapon re-coil energy recovery system as well as other energy recovery systems, such as from walking, running, wind, solar, or remote laser charging systems, can also be used to re-charge batteries as well as to power loads.
Advantages
[0014] The primary advantage is a supply standard is established such that heterogeneous types of equipment modules can become standardized and thus can connect, communicate, and interact with each other seamlessly and immediately by optimizing and prioritizing shared supply consumption as well as tracking shared supply levels, health, and shared supply flows. Ultimately reducing the total supply mass required to be carried by mobile units.
[0015] Another advantage is to be able to optimize sensing and monitoring of remote health, as well as optimize prioritized distribution of supplies to mobile field personnel modules.
[0016] A further advantage is to be able to route and network health data, even where communications abilities are sparse or limited. Other advantages are dual use of material as energy storage, energy generation, along with original function.
BRIEF DESCRIPTION OF THE FIGURES
[0017] FIG. 1 depicts a light weight wearable vest with wireless standard supply cell pockets and multiple quadrants where one quadrant is shown with standardized wired supply cells and an optional standardized connector is shown.
[0018] FIG. 2 shows a block diagram of a standardized intelligent supply module cell as well as how all the standardized intelligent supply module cells are interconnected within the vest.
[0019] FIG. 3 shows a high level control algorithm that runs on all of the standard intelligent device module cell controllers.
[0020] FIG. 4 shows interconnectivity between intelligent modular cells as well as their connection to a larger network.
[0021] FIG. 5A shows a battery supply embedded inside a bullet head with polarity markings.
[0022] FIG. 5B shows a magazine of battery bullets that can be discharged in sequence, depending on application as first in first discharged before being used.
[0023] FIG. 6 shows a weapon re-coil energy recovery system to act as a localized energy source.
DRAWINGS-REFERENCE NUMERALS
[0000]
2 standardized intelligent modular cell
2 A standardized intelligent module main vest cell wired
2 B standardized intelligent pocket module cell wirelessly coupled
2 C primary controller as standardized intelligent module main vest cell
2 D secondary controller as standardized intelligent module main vest cell
4 standard connector and/or wireless or accessory ports
4 A blank standard connector socket
4 B standard voltage level v1 (example 8 volts) & current level i1 (example 1 amp) socket
4 C standard voltage level v2 (example 12 volts) & current level i2 (example 50 milliamps) socket
4 D other standard socket
4 E platform bus
6 wireless power and data distribution
6 A laser or optical power and data distribution
8 global power and data distribution cloud
10 controller or embedded computer system that can have unit identification and configuration data as well as a display
10 A primary controller module: can contain unit identification, configuration, sensor, and central supply distribution module
10 B backup (secondary) controller module: can contain unit identification, configuration, sensor, and central supply distribution module
12 localized source
14 localized sink
16 localized source distribution, re-sourcing control system and cabling
18 localized health monitor and criticality control system
18 A intensity of local source in-flow sensor for localized health monitor
18 B voltage, energy, level, volume, pressure, or other local source indication sensor
18 C intensity of local sink out-flow sensor for localized health monitor
18 D voltage, energy, level, volume, pressure or other local sink indication sensor
18 E other sensors
18 F data coupling
20 supply (sink and/or source) coupling
20 A positive terminal
20 B negative terminal
24 start
26 initialize
28 check source status
30 check re-sourcing status
32 check sink usage status
34 run controlled source utilization criticality sequence
36 add/remove/isolate sinks and sources based on health status and criticality
38 transfer and process health data and supplies
40 system shutdown condition check
42 shutdown
100 standard intelligent interconnected modular system
100 A standard intelligent interconnected sub-module system as quadrant 1 of vest
100 B standard intelligent interconnected sub-module system as quadrant 2 of vest
100 C standard intelligent interconnected sub-module system as quadrant 2 of vest
100 D standard intelligent interconnected sub-module system as quadrant 4 of vest
100 E standard intelligent interconnected module system as dismounted field unit
100 EA standard intelligent interconnected module system as dismounted field unit furthest to the East 112
100 EB standard intelligent interconnected module system as dismounted field unit 2 nd from the East 112
100 EC standard intelligent interconnected module system as dismounted field unit 3 rd from the East 112
100 ED standard intelligent interconnected module system as dismounted field unit 4 th from the East 112
100 EF standard intelligent interconnected module system as dismounted field unit 4 th furthest to the West 114
100 F standard intelligent interconnected module system as field supply generator unit
100 G standard intelligent interconnected module system as field parachuted supply unit
100 H standard intelligent interconnected module system as landed supply unit
100 I standard intelligent interconnected module system as deployed solar re-charging station unit
100 J standard intelligent interconnected module system laser and/or microwave re-sourcing unit
100 K standard intelligent interconnected module system laser and/or microwave receiving unit
100 L standard intelligent interconnected module system vehicle
100 M standard intelligent interconnected module system land rover vehicle
100 N standard intelligent interconnected module system small spy drone vehicle
100 O standard intelligent interconnected module system drone vehicle carrying supplies
100 P standard intelligent interconnected module system re-supply aircraft
100 Q standard intelligent interconnected module system troop transport helicopter
100 R standard intelligent interconnected module system submarine
100 S standard intelligent interconnected module system Global Hawk/Predator or other drone
100 T standard intelligent interconnected module system satellite or space craft
100 O standard intelligent interconnected module system ground earth station
100 V standard intelligent interconnected module system head quarters
101 region of interest
102 buildings
104 vehicle
106 mountain ranges
108 coastline
110 water
112 East Direction
114 West Direction
200 bullet head, serving as positive terminal of bullet battery
201 bullet battery
202 bullet shell, serving as negative terminal of bullet battery (continuity controlled by 2 in case ammo gets in water etc.)
204 cathode
206 anode
208 current collector
210 separator
212 insulator cap
214 bullet head (negative side)
216 insulator
218 shell space
220 powder
222 permanent magnet breech bolt
224 water proof insulated coil
226 weapon body
228 spring
228 A positive plate spring
228 B magazine spring
232 negative plate
234 ammunition magazine holding battery bullets
236 ammunition magazine frame
238 to gun chamber
240 magazine spring plate
DETAILED DESCRIPTION
[0123] The present invention is described in part in terms of functional block components and various processing steps. Such functional blocks can be realized by any number of hardware and/or software components configured to perform the specified functions. The invention may be practiced in any number of contexts. The data communication and supply control system described herein is merely one exemplary application of the invention.
[0124] In FIG. 1 an example application of the invention is shown where a standard intelligent interconnected module 100 is shown as a vest with multiple standard intelligent interconnected module quadrants 100 A, 100 B, 100 C, and 100 D. The top left quadrant 100 A is shown separately with standardized intelligent interconnected modules as wired main vest cells 2 A that serve primarily as batteries (sources) as well as wireless pocket cells 2 B that primarily serve as loads (sinks). A standardized intelligent modular cell acting as primary controller 2 C and backup controller 2 D modules are shown as part of the standard intelligent interconnected modular system 100 unit. The controllers 2 C and 2 D contain identification, configuration, sensor systems, and central supply distribution control to keep track of identification as well as the configuration of the module 100 , as well as any supply health sensor information for module 100 . Controllers 2 C and 2 D can be designed such that the internal vest cells 2 A are discharged first so that wireless cells 2 B can be swapped fully charged between users if needed. The health sensors can include heart rate, blood pressure, temperature, electrocardiogram readings, or other useful readings such as overall supply levels including ammunition, water, food, weapons or other pertinent supplies. Standardized connector socket plug 4 controlled by controllers 10 is shown at the bottom of FIG. 1 with blank standardized connector sockets 4 A, for expansion, as well as standardized voltage and current level socket 4 B and other standardized voltage and current level socket 4 C. Other standard sockets 4 D are used for specified voltage settings as adjusted by standardized connector pin plug setting to ground or as desired to provide the voltage and current output to a desired specified standard set level to satisfy heterogeneous equipment power requirements if needed.
[0125] In FIG. 2 a standardized intelligent module cell 2 that forms the basis of the standard intelligent interconnected module 100 . Inside the standardized intelligent module cell 2 the localized source 12 is shown of which can be internal and/or external to module cell 2 through wired or wireless supply coupling 20 as a battery, capacitor, power supply, ammunition, fuel source, explosives, canteen, food supply, or any other form of supply that needs to be tightly controlled and managed throughout a mission. Localized source 12 can also be a standard battery case that holds one or more standard size AAA, AA, A, B, C, D or other standard battery sizes, or be a proprietary battery. Localized sink 14 acts as a load as the consumer of the source and/or supply of which can either be internal and/or external to module cell 2 through wired or wireless supply coupling 20 .
[0126] Localized supply/source and resourcing/re-supplying distribution and control system 16 manages the resourcing/re-supplying of the localized supply/source. The supply management system 16 can limit the supply (current) locally through supply (current) limiters, or can inform or control the sink 14 on consumption flow rates, as well as communicate supply or re-supply requests through health monitor 18 that can route to other system modules 100 through data coupling 18 F.
[0127] The supply control system 16 uses localized health monitor and criticality control system 18 to manage localized sink 14 consumption and re-supplying of supply 12 . The localized health monitor and criticality control system 18 utilizes intensity sensor shown as “I” 18 A that measures source supply flows (current) and direction (adding or subtracting), as well as source potential sensor shown as “V” 18 B for voltage or supply level or supply deficit. The localized health monitor and criticality control system 18 also uses sink intensity sensor shown as “I” 18 C that measures sink supply flows and direction, as well as source potential sensor shown as “V” 18 D for voltage or supply level of localized load or sink that consumes the source. The localized health monitor and criticality control system 18 can also use other sensors 18 E to make decisions on how to adjust and control supply flows between localized source 12 and sink 14 , as well as through external sources through wired or wireless supply coupling 20 . If the module is a critical module (Such as “Level A” to use avionics parlance), then the module can use its own localized source 12 last, utilize lower level external sources as much as possible until drained, and then use internal localized source 12 . The localized health monitor and criticality control system 18 uses wired and/or wireless data coupling 18 F to communicate and route to/from other standard intelligent module cells 2 and/or primary controller 2 C and/or secondary controller 2 D and between intelligent interconnected module system 100 to module system 100 for communications.
[0128] At the bottom half of FIG. 2 is standard intelligent interconnected module 100 with only wireless standard intelligent module cells 2 B that are interconnected wirelessly through wireless power and data distribution 6 .
[0129] In FIG. 3 the software 10 C that runs on the controllers 10 is shown starting at 24 , where the control system is initialized at 26 where a check is done on source status 28 , as well as a check on re-sourcing status 30 . A check on sink usage (consumption) status occurs at 32 . Source utilization criticality sequence is executed on process block 34 where at process block 36 the adding, removing, isolating of sinks, and sources based on health status and criticality occur. At process block 38 the prioritized controlled transfer and processing of health data, and supply flows are executed. At decision block 40 the system checks if a manual or automatic shutdown is needed. If no shutdown is needed, process returns flow to check the source status 28 and so on. If a shutdown is needed, the shutdown process occurs at process shutdown 42 .
[0130] In FIG. 4 a higher context level of all standard intelligent interconnected modules 100 as dismounted field units 100 E and other units 100 A through 100 V how they are coupled through wireless means 6 are shown. Dismounted standard intelligent interconnected module field units 100 E are shown in FIG. 4 along mountain terrain surfaces 106 can be connected wirelessly through an ad hoc distributed mesh network of radio waves as wireless signals 6 or optical wireless via laser beams or microwaves as 6 A of which, through proper alignment, can be used to transfer energy as well as data to recharge batteries, or to move and communicate in a less detectable manner and still transfer data, and adjust prioritized critical supply flows.
[0131] Near region of interest 101 , buildings 102 , and vehicle 104 , a forward dismounted field unit 100 EA farthest to the East 112 is interconnected with another nearby dismounted field unit 100 EB near dismounted field unit 100 EA using automatically tracked and locked laser beam 6 A by dismounted unit 100 EA to maintain radio silence, but still able to communicate to ad hoc mesh network 6 . A third forward dismounted field unit 100 EC communicates with dismounted forward unit 100 EB through radio signal 6 to 100 EC where radio signal 6 is purposely out of range of forward dismounted field unit 100 EA to maintain radio silence.
[0132] Forward operating spy drone 100 N is controlled and communicated by dismounted field unit's 100 EC or 100 EB using wireless signal 6 , or if desired, using an automatically tracked and locked laser beam 6 A not shown as substitute to wireless radio signal 6 . Forward operating semi-autonomous supply drone 100 O is shown bringing supplies to, and communicating via wireless signal 6 with forward operating unit 100 EC. Drone 100 O can be designed to operate just a few feet above terrain to avoid detection and autonomously or semi-autonomously move dismounted needed supplies between forward operating units 100 E and local supply source 100 H being resupplied by solar charging unit 100 I through localized source distribution and re-sourcing control system cabling 16 if supplies are rechargeable batteries, or elsewhere for other needed supplies. Forward operating unit 100 EC is shown in wireless radio signal 6 ranges of forward operating units 100 EE and 100 ED that are further to the West direction 114 . Status data of forward supply source 100 H is obtained through forward unit 100 ED as well as through forward operating land rover unit 100 M through wireless signals 6 . Status of forward dismounted units 100 EA, 100 EB, 100 EC, and 100 ED is communicated wirelessly via wireless signals 6 through forward operating land rover unit 100 M and forward operating dismounted support unit 100 EF.
[0133] Fast forward remote unit battery charging is shown between laser receiving and battery charging unit 100 K and laser re-sourcing unit 100 I using laser beam 6 A where laser re-sourcing unit 100 J is powered by generator unit 100 F through localized source distribution and re-sourcing control system cable 16 . Laser charging unit 100 J can be controlled and monitored by dismounted unit 100 EF through wireless signal 6 .
[0134] Laser re-sourcing unit 100 J can be designed to optically communicate to helicopter 100 Q via autonomously tracking laser beam 6 A to maintain radio silence, or alternatively using wireless signal 6 when radio silence is not needed.
[0135] Land rover vehicle 100 M can communicate wirelessly to helicopter 100 Q, supply aircraft 100 P, parachuted supply 100 G, as well as forward operating dismounted units 100 EE, 100 ED, and solar re-charging supply unit 100 I using wireless signals 6 .
[0136] Helicopter 100 Q can communicate with satellite 100 T, high altitude drone 100 S via wireless means 6 , whereby satellite can communicate to aircraft carrier 100 R or other ship in water 110 near shore 108 , as well as to and from high altitude drone 100 S also through wireless means 6 .
[0137] Satellite 100 T can communicate via wireless means 6 to and from a command and control headquarters 100 V through other satellites 100 T and ground earth station 100 U to global network cloud 8 .
[0138] In FIG. 5A , a further embodiment with an emphasis on dismounted field unit weight reduction, a standardized intelligent module cell 2 is shown embedded inside a bullet 201 where the bullet head serves a dual purpose as both projectile and battery where standardized intelligent module cell 2 is coupled with battery through conductors 20 . The battery can be manufactured inside the bullet 201 by drilling/boring or forging out the bullet head so that space can be made for the battery parts and/or other materials while maintaining enough structural volume for structural integrity for the bullet to remain intact after impact. The embedded battery contains conductive positive terminal 200 , with separator 204 , anode 206 , current collector 208 , and insulator cap 212 . Bullet 201 can be designed sturdy enough to stay intact upon impact of a hard surface to minimize fragments, and/or be further enhanced so that the mode of the bullet function can be changed electronically and or electro-mechanically, such as to track a target if hit, using active or in-active (passive) radio frequency identification tags inside 2 , or to make the bullet more lethal with one shot by exploding inside the target by mixing cesium and water upon impact. This can be done by using similar technology used in triggering air bag deployment or by impact triggering a charge to break a separator that mixes the substances to produce an explosion.
[0139] Bullet head 200 is held together with insulator cap 212 with bullet head negative end 214 . Current flow between current collector 208 and bullet head negative end 214 is controlled by standardized intelligent module cell 2 enabling it to switch current on and off to control discharge, as well as re-charge sequence order, such as first in first out in magazine order. Explosive electrical isolator 216 is shown to prevent unintentional triggering of gun powder 220 due to electrical spark between bullet shell 202 serving as negative terminal of the bullet battery and bullet head 214 in air gap 218 . Communications from modular cell 2 in bullet 201 to/from modular cellular system 100 of FIG. 1 primary controller 2 C can be established by modulating positive terminal 200 and/or negative terminal 202 using supply lines 20 thereby combining supply coupling 20 with data coupling 18 F. This same combination of coupling can be used in other applications of modular cell 2 .
[0140] FIG. 5B shows battery bullets 201 A, 201 B, 201 C, 201 D, 201 E, 201 F inside an ammunition magazine 234 with positive terminal plate 234 held by springs 228 A and moved by magazine spring 228 B that holds plate 240 . The bullet batteries are discharged in sequence of first in first out in magazine order, so that the bullet batteries first to arrive in the chamber are significantly discharged unless set to track using active radio frequency identification tags.
[0141] FIG. 6 shows a charging system utilizing kick back from a weapon breech bolt using a permanent magnet 222 connected to a spring 228 inside a barrel 226 inducing current into coil 224 when the weapon is fired. Alternating current flows in coil 224 through bridge rectifier and charges capacitor and batteries or provides power to other equipment. Kick back energy can be transferred to other coils, and/or a flywheel connected to a generator, such as to a flywheel with a crank shaft to operate much like a piston in an engine but mechanically designed to drive the flywheel only during the re-coil operation (like a pull line on a lawn mower allowing the flywheel to spin freely from the breech bolt 222 . The inertial energy from the flywheel can also serve to stabilize the aim of a weapon through gyroscopic action.
[0142] The idea of gyroscopic power generation can be expanded to an exoskeleton joint energy capture system of field personal and can also be included into gyroscopic power generation of shock absorption from footsteps, as well as to body surface compression spaces such as from sitting or from touching a surface of which would otherwise be converted to heat energy, but is converted to potential electrical energy instead.
[0143] Operation
[0144] The main operation of all the embodiments is efficient and prioritized utilization of all standardized intelligent modular cells 2 that are building blocks of the standard intelligent interconnected modular system 100 so that they can all function interchangeably and seamlessly together towards a common goal of efficiently managing supplies and feeding, as well as generating and moving supplies to critical operations in the field. Part of the efficiency improvement is allowing field operators to do more operational activities with less weight by sharing standardized intelligent modular cells 2 .
[0145] Standardization is achieved by having an established standard connector 4 that can be a connector of any type, so long as it is standardized for access by all intelligent standard wired module types 2 A, in a similar manner as a standard 12 volt cigarette lighter connector is to an automobile, or a 120 volt alternating current outlet is to a home as a standard plug and socket configuration in North America. The voltage levels on connector 4 can be one or a set of any established levels and can be adjustable by pin setting or otherwise, so long as they are set to standard levels that all standard wired module types 2 A are able to set and function as desired and are recognized. For wirelessly connected standardized intelligent module cells 2 B the wireless behavior of communications and energy transfer can be established in numerous ways, such as a standard geometry charging surface in a similar manner as a standard electric toothbrush and toothbrush holder.
[0146] Each standardized intelligent modular system 100 has at least one standard intelligent module cell 2 operating as primary controller 2 C, and one or more designated as backup controller 2 D to immediately be able to take over if primary controller 2 C fails. If primary controller 2 C fails, then the backup controller 2 D or other backup controller 2 D operates as a new primary controller 2 C replacing the failed primary controller 2 C. A new working backup controller 2 D is then established, in case the new primary controller 2 C fails, and so on, until all available controllers on intelligent modular system 100 are consumed. Control transfer can be done using status messages between all standard intelligent modular cells 2 inside standard intelligent interconnected modular system 100 . Messages between internal standard intelligent modular cells 2 and external systems can be routed through primary controller cell 2 C or through another cell 2 that the primary controller 2 identifies and designates as a communication module cell 2 .
[0147] Communications between cells 2 can be of any standard; so long as all cells 2 use that same standard. One ubiquitous communications standard commonly used at the time of the invention is Ethernet and wireless Ethernet standards established by the Institute of Electrical and Electronics Engineers (IEEE). If wireless communications is desired in operation modes where radio silence is essential, such as when using jammers to prevent improvised explosive devices (IED's) from triggering, optical communications 6 A as part of data coupling 18 F can be used inside and between wireless cells 2 B while laser communications 6 A can be used between standard intelligent modular cell system 100 through an established standard intelligent wireless module cell 2 B designated for external laser communications.
[0148] As provided in FIG. 2 inside the standard intelligent modular cell 2 there is a localized sink 14 that acts as a load or consumer of supplies whether it be energy, or water, it represents consumption where supplies drain to from source 12 or external source 12 through supply coupling 20 . The status of sink 14 and source 12 behavior is determined by voltage (or volume or other) sensor 18 D and 18 B as well as through flow intensity sensor 18 C and 18 A. Accurate predictions on when sink 14 will deplete source 12 can be made and provided by these sensor readings and processing from the localized health monitor and criticality control system 18 . The predictions can also limit, increase, decrease, shut off, turn on, or adjust flows from localized source 12 and other supply sources through supply coupling 20 using flow (or current) limiters established inside localized source distribution and re-sourcing control system 16 . These predictions can also provide automatic or manual requests out through data coupling 18 F to rapidly order new supplies out to the field of which can be routed and exchanged between standard intelligent modular systems 100 . Manual supply and flow control requests can be executed through unit identification, configuration, and control computer module 10 of which can control localized sink 14 and localized source 12 supply flows through localized source distribution and re-sourcing control system 16 for local flows, or for the entire standard intelligent interconnected modular system 100 through data coupling 18 F using a communication modular cell 2 B to other modular systems 100 routed all the way to supply source using supply routing path tables that are continually updated based on supply status where a supply transfer process can begin and be tracked.
[0149] Health information can be formatted in any standard format so long as all intelligent standardized cells 2 can understand the format. One example is to use eXtensible Markup Language (XML) to format the messages where the data can be compressed and encrypted for transfer where it is decompressed and decrypted at the other end. An example of one message in XML is what follows. This is merely an example of just one message type, and there are many different types of messages that can be transferred as well as many possible different types of data that can be shared and optimized between individual cells 2 and intelligent modular systems 100 such as supply ordering messages, region status messages, broadcast messages, and many other types of messages for hierarchal or flat, or other structure of command, control, and supply routing optimization, automation, and monitoring. Other data can be shared between modules, such as position, temperature, or position of something of interest, or any other useful data.
[0000]
<ModularCellSystemHealthMessage>
<NumOfOnboardUsers>1</NumOfOnboardUsers>
<NumOfModulesOnboard>37</NumModulesOnboard>
<UserStatus>
<UserID>8675309</UserID>
<Vitals>
<HeartRate>60 BPM</HeartRate>
<BloodPressure>120/80 mmHg</BloodPressure>
<BodyTemperature>98.9F</BodyTemperature>
<FatigueLevel>5</FatigueLevel>
</Vitals>
<EnvironmentTemperature>120F</EnvironmentTemperature>
<Humidity>98%</Humidity>
<UserPersonalSupplyStatus>
<water>
<Volume>3 liters</Volume>
<AvgUsageRate>1 liter/hour</AvgUsageRate>
<EstRemainingTime>2 hours</EstRemainingTime>
</water>
<food>
<Volume>3 units</Volume>
<AvgUsageRate>0.25 units/hour</AvgUsageRate>
<EstRemainingTime>24 hours</EstRemainingTime>
</food>
</UserPersonalSupplyStatus>
</UserStatus>
<MainBatteryStatus>
<NumMainBatteries>32</NumMainBatteries>
<NumMainFunctionalBatts>31</NumMainFunctionalBatts>
<TotalAmpHoursRemaining>346</TotalAmpHoursRemaining>
<AvgEnergyUsageWatts>15</AvgEnergyUsageWatts>
<PeakEnergyUsageWatts>25</PeakEnergyUsageWatts>
</MainBatteryStatus>
<WeaponStatus>
<NumOfWeapons>1</NumOfWeapons>
<Weapon>
<WeaponType>M16</WeaponType>
<AmmunitionType>35 mm battery
cells</AmmunitionType>
<AmmunitionQuantity>204</AmmunitionQuantity>
<AmmoAvailAmpHours>252</AmmoAvailAmpHours>
<AverageAmmoUsage>10/hour</AverageAmmoUsage>
<PeakAmmoUsage>5/hour</PeakAmmoUsage>
<Weapon>
</WeaponStatus>
</ ModularCellSystemHealthMessage > | A mobile, networked, optimized, supply, power, generation, and distribution system that includes a light weight vest or suite that contains a highly reliable, standard, efficient, power and data storage system. The system provides modular standardized and adaptive means of efficiently powering, controlling, and monitoring the health and supply of one or more standardized portable load and data devices. Supplying and re-supplying is achieved through standardized modular means. Reliability and efficiency is achieved through sensing, redundant switching, and controlling fully protective efficient utilization of energy storage weight and standardized device load circuits. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a bullet setting device used by competitive marksmen who use muzzle loaders with black powder.
2. Description of the Prior Art
It is known to strike a loading hammer with one blow in order to drive a bullet sitting on a patch into the rifling of a muzzle loader. The bullet which is used for this procedure can have a round or ogival shape. Next, the bullet must be driven at least 1-2 cm deep into the gun barrel by means of a bullet setting rod having a length of 1-3 cm. The bullet setting rod may be fastened to this hammer itself or to a wooden ball. Then, the palm of the user's hand hits hard on the hammer or the wooden ball to drive the bullet at least 1-2 cm deep into the barrel. Thereafter, the subcaliber hammer handle or the extended setting rod on the wooden ball is used to drive the bullet at least about 10 cm further into the gun barrel by additional strikes with the user's palm or with the hammer. Finally, a ramrod is inserted into the gun barrel to set the bullet by pushing the bullet down to the charge. Since only bullets tightly seated in the barrel produce good hit patterns, a great amount of force must be expended to obtain tightly seated bullets. As a result, contusions and injuries sometimes occur. Tightly seating each bullet is the most difficult and time consuming process during loading.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a bullet setting device which simplifies, facilitates and shortens the time required for the difficult process of setting tightly guided patch bullets.
The above and other objects are accomplished by the invention in which a bullet setting device for setting a bullet in a muzzle of a gun comprises a rod having a guide rod portion and a driving rod portion, the driving rod portion including a projection at one end of the rod; a driving anvil disposed on the rod and separating the guide rod and driving rod portions from one another; a setting anvil disposed on the rod at the other end of the guide rod portion; a striking member slidably disposed on the rod and movable between the setting anvil and the driving anvil; and a handle adjacent the setting anvil.
The impacts required for driving bullets into muzzle-loader barrels in the selected striking direction during the setting, loading or bullet extraction processes are favorably effected by the striking member of the device.
It is of particular advantage that the user can invert the device until the respectively required anvil (either the setting anvil or the driving anvil) is between the location of the striking member and the muzzle-loader barrel. This places the required anvil in a position where it can be utilized without further manipulation.
A hardwood part disposed on the setting anvil has at its planar upper (outer) surface a centrally disposed circular concave recess. Setting members having diameters to accommodate different bullet calibers are exchangeably fastenable to the end of the guide rod portion.
When using muzzle loading pistols, the short setting member can be replaced by an extended setting rod which has a length corresponding to the length of the entire barrel and is adapted in diameter to the bullet caliber. This setting rod can be fastened to the driving rod portion to serve as the ramrod. The bottom of the setting rod can be unscrewed and replaced with cleaning brushes, wiping rag holders or bullet extractors.
An adapter sleeve is also connectable with the projection on the driving rod portion. The adapter is provided with two internal threads, one at each end. One thread is connectable to the projection on the driving rod portion and the other thread is connectable to one end of a ramrod. The ramrod is usually an accessory for the weapon and is even longer than the setting rod.
The striking member includes a bore therethrough which has a diameter at the ends of the bore which is larger than the diameter of the remainder of the bore. Due to this arrangement the small material deformations which occur when the striking member hits the respective anvil will not interfere with the free sliding of the striking member on the guide rod portion.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal side view, partially in section, of a preferred embodiment of the device according to the invention.
FIG. 2 is a longitudinal side view, partially in section, of a setting rod forming part of a preferred embodiment.
FIG. 3 is a longitudinal sectional view of an adapter forming part of a preferred embodiment.
FIG. 4a is a side view of a cleaning brush forming part of a preferred embodiment.
FIG. 4b is a side view of a bullet extractor forming part of a preferred embodiment.
FIGS. 5a to 5d are longitudinal side views of the preferred embodiment, illustrated in various stages of operation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a preferred embodiment of a bullet setting device generally indicated by reference numeral 1. Bullet setting device 1 is composed of a round steel rod having an overall length of about 360 mm and a diameter of about 7 mm. The rod is divided into two portions, a guide rod portion 2 and a driving rod portion 7. Guide rod portion 2 has a length of approximately 220 mm and driving rod portion 7 has a length of approximately 125 mm. A generally cylindrical striking member 3 is displaceably provided on guide rod portion 2. Striking member 3 is composed of a piece of round steel having a length of about 50 mm, a diameter of about 30 mm and a mass of about 250 grams. Striking member 3 can easily slide up and down on the guide rod portion 2.
The path of striking member 3 is delimited by two thickened portions which have abutment faces and form a setting anvil 4 and a driving anvil 5. Setting anvil 4 is screwed onto one end of the rod while driving anvil 5 is fixed to the rod adjacent the common end of the guide rod portion 2 and the driving rod portion 7. The driving anvil 5 has a length of about 10 mm and a diameter of about 14 mm. The setting anvil 4 has a length of about 25 mm and a diameter of about 12 mm.
Striking member 3 can easily be moved by the user's thumb and index finger so that the striking member 3 can forcibly strike the setting anvil 4 as well as the driving anvil 5. By this movement the mass of striking member 3 acts as a hammer against the respective anvil. The striking member 3 is a member having a basically cylindrical configuration. However, for better manipulation striking member 3 can be tapered toward the center and provided with transverse grooves to enhance gripping.
Striking member 3 includes a bore therethrough whose opposite ends slightly widen at 6 and 6' so that slight material deformations which occur during striking do not adversely influence the free sliding of the striking member 3 on the guide rod portion 2. The widened portions 6 and 6' each border on the planar surfaces of the striking member 3.
Both ends of the steel rod (composed length portions 2 and 7) are provided with an external thread which cooperates with an internal thread of the setting anvil 4 to hold the latter at the end of the guide rod portion 2. Setting anvil 4 is inserted into a handle 8 which is fastened thereto.
In the center of the planar surface of the handle 8 located on its upper side is a circular concave recess 9. Recess 9 serves as a centering aid for the first strike on the bullet.
Handle 8 is of wood or a plastic material. A nonillustrated alternative to the handle 8 fastened to setting anvil 4, the handle 8 may contain a self-cutting threaded sleeve which is screwed in a force-locking manner to the guide rod portion 2. An abutment surface for the striking member 3 may be formed at one end of the handle 8, by covering the sleeve opening or placing a washer therebetween. This abutment surface will correspond in position to the position of the annular frontal face of setting anvil 4.
A washer 10 is attached to the driving anvil 5 adjacent its surface facing the driving rod portion 7. The washer 10 has a diameter of about 24 mm and serves to limit the extent to which driving rod portion 7 is inserted into the gun muzzle by the driving process. To the washer 10 there is glued a leather disc which protects the gun muzzle. The leather disc is attached to the flat surface of washer 10 facing toward the driving rod portion 7.
At the end of driving rod portion 7 there is a projection 11 which has an external surface provided with a thread to receive a bullet setting member 12 made of brass. At the impact end of bullet setting member 12 is a concave portion 13 which is adapted to the shape of the bullet to be set.
The exchangeable setting members 12 have diameters of 7.5 mm, 10 mm or 14 mm, so that any of the respective bullet calibers of the muzzle loaders may use the bullet setting device 1 according to the invention. Since setting member 12 has different uses such as for a setting path of about 120 mm and as a ramrod for setting the bullet down at the bottom of the piston barrel, setting members may have lengths from about 25 mm to about 125 mm.
Setting member 12 may be exchanged for a setting rod 14 shown in FIG. 2. Setting rod 14 has a length of 135 mm and has an exchangeable bottom member 15 disposed at its end. The exchangeable setting rod 14 is preferably made of brass with the bottom member 15 being made of plastic or wood.
Setting rod 14 and bottom member 15 are designed to have a length that allows all customary muzzle loader pistols to be loaded without the ramrod provided for that purpose.
FIG. 3 shows an adapter 16 that allows a ramrod to be attached to the bullet setting device. Adapter 16 has a cylindrical configuration with one bore disposed in each end thereof. Each bore is provided with an internal thread for allowing the adapter 16 to threadedly engage both the projection 11 and the ram rod.
FIG. 4a illustrates a cleaning brush 17 and FIG. 4b illustrates a bullet extractor 18. Both the cleaning brush 17 and the bullet extractor 18 have a corresponding thread at one end with which they can be selectively inserted into the end of setting rod 14 instead of bottom member 15.
The operation of the bullet setting device will now be described with reference to FIGS. 5a to 5d.
Bullet setting member 1 is gripped at striking member 3 by the user's thumb and index finger. Bullet setting member 1 is then positioned so that gravity causes setting anvil 4 to slide down and come to rest lightly on the bullet to be loaded. Since the bullet is still projecting from the muzzle this helps to center the setting anvil because the bullet protrudes into the central concave portion 9 of the handle 8. In this position, the striking member 3 is below and adjacent to driving anvil 5 with the bullet setting device 1 being in an approximately vertical position (FIG. 5a). Then a slight tap with the striking member 3 drives the bullet easily into the rifling of the muzzle loader (FIG. 5b). Without having to release hold of the striking member 3, the striking member 3 is raised until it abuts at the driving anvil 5 thereby lifting the device. Then the bullet setting device 1 is turned about 180°, about an axis transverse to the rod. Following this rotation, driving rod portion 7 points down and slides toward the muzzle due to gravity (FIG. 5c). Since the striking member 3 is now adjacent the setting anvil 4, the striking member can perform short downward strokes against driving anvil 5. After each stroke the driving anvil 5 moves toward the muzzle until, after two to three strokes, the leather disc contacts the muzzle, terminating this process.
In this state, the bullet is in the barrel to a depth of about 120 mm. The bullet is thus in a pressed-in state and can easily be brought onto the charge in the traditional manner by driving the bullet with the ramrod of the muzzle loader.
The entire process takes only a few seconds and is accomplished with great ease and without any major expenditure of force on the part of the user.
When loading pistols, the setting rod 14 (FIG. 2) which has a length corresponding to the length of the barrel 12 is screwed to the projection 11 of the driving rod portion 7, replacing the bullet setting member 12. With a bullet setting depth of 120 mm, the limiting member 10 of the driving anvil 5 has not yet seated on the end of the muzzle. In this position, the striking member 3 can be released because the driving rod portion 7 or the setting rod 14 is positioned in the barrel and holds the bullet setting device 1. Now the free hand can be placed on the handle 8 and a downward pressure applied to the device 1 to bring the bullet onto the charge. By use of this procedure, a separate ramrod is no longer required.
The invention may find advantageous use when a bullet is to be extracted from the barrel. Various circumstances arise that make it necessary to extract the bullet and its patch from the barrel after they have been loaded to the bottom of the barrel. One such circumstance is where the powder was not previously loaded. The prior art method of bullet extraction was to use the ramrod which had a bullet extractor screwed to the end. The ramrod wash pushed down to the bullet and then rotated so that the corkscrew helixes and screw thread gripped the bullet. Because the ramrod only projected slightly from the muzzle it was generally complicated and difficult to pull the ramrod and the wedged-in bullet from the muzzle. According to the present invention, the adapter 16 is screwed onto projection 11 and the ramrod of the gun is screwed into the adapter 16. The ramrod containing the bullet extractor 18 is now inserted into the muzzle and the bullet extractor 18 is attached to the bullet. The striking member 3 may now be forced upwardly against setting anvil 4 thereby dislodging the bullet from the wedged-in condition. Once the bullet is released from the wedged-in condition, the bullet can be removed from the barrel by pulling up on the handle 8.
Another advantage of the present invention is that the setting, loading and extracting of bullets in muzzle-loaders regardless of the caliber or the length of the barrel, is possible with the same bullet setting device, thereby making the device very versatile.
The bullet setting device 1 according to the present invention permits manipulations which are also suitable for precision firearms. For precision firearms, the precision barrels are treated very gently, so as to produce the identical conditions for all successive shots thereby limiting the unavoidable "spread" to a minimum. To accomplish a minimum "spread", the following measures are utilized in addition to those discussed earlier: commercially available muzzle protectors made of plastic or another suitable shock-absorbing material are used to enclose the rod and these are placed on the driving rod portion 7 or on the setting rod 14 to avoid any contact with the muzzle itself.
Markings or delimiting sleeves may be provided on the driving rod portion 7 or the setting rod 14 to assist in preventing the device from penetrating too deeply into the barrel.
Additional protection of the barrel is realized if the brass setting members (which are designed for the respective barrel caliber of the weapon) are given a length so that their placement against the inner barrel bore prevents canting of the setting member 12 or bottom member 15 on the first few centimeters of the loading path. This means that the driving rod portion 7 or setting rod 14 are unable to touch the inner muzzle edge of the barrel because the muzzle protector, which has a length of about 3 cm, is able to slide down or is pushed by the user until it engages the muzzle. This movement of the muzzle protector protects the muzzle edge from contacting the driving anvil 5.
Additionally, the driving rod portion 7 and/or the setting rod 14 is preferably provided with a jacket which is also composed of plastic or the like.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | A bullet setting device for setting a bullet in a muzzle of a gun includes a rod having a guide rod portion and a driving rod portion. The guide rod portion and the driving rod portion have a first end which is common to both rod portions and the rod further has respective opposite second and third ends. A driving anvil is disposed at the first end, a setting anvil is disposed at the second end and a striking member is slidably disposed on the rod and being movable between the setting anvil and the driving anvil for selectively impacting the one or the other anvil. An initial bullet setting device is mounted on the rod at the second end for introducing the bullet into the muzzle upon striking the setting anvil with the striking member. Further, a handle is disposed adjacent the setting anvil; and a projection is provided on the rod at the third end for receiving a bullet handling device for engaging the bullet situated in the barrel, upon striking the driving anvil with the striking member. | 5 |
BACKGROUND
[0001] The present invention relates to packer and bridge plug type tools used in wellbores and more particularly to limiter assemblies, which resist extrusion of packer elements when exposed to borehole conditions, especially high pressure and high temperature.
[0002] In the drilling or reworking of oil wells, a great variety of downhole tools are used. For example, but not by way of limitation, it is often desirable to seal tubing or other pipe in the casing of the well, such as when it is desired to pump cement or other slurry down the tubing and force the cement or slurry around the annulus of the tubing or out into a formation. It then becomes necessary to seal the tubing with respect to the well casing and to prevent the fluid pressure of the slurry from lifting the tubing out of the well or for otherwise isolating specific zones in a well. Downhole tools referred to as packers and bridge plugs are designed for these general purposes and are well known in the art of producing oil and gas.
[0003] Packers generally rely on a packer sealing assemblies to seal the wellbore. Traditionally such assemblies are comprised of at least one elastomeric sealing element and at least one mechanically set slip. Typically, a setting tool is run in with the packer to set it. The setting can be accomplished hydraulically due to relative movement created by the setting tool when subjected to applied pressure. This relative movement causes the slips to ride up on cones or wedges and extended into biting engagement with the surrounding casing or wellbore. At the same time, the sealing element is compressed into sealing contact with the surrounding casing or wellbore.
[0004] Packer element back-up shoes and rings have been employed to support the ends of the packer sealing elements as the elements are expanded into contact with a borehole wall. These back-up shoes or rings also may limit the axial extrusion of the packer sealing elements; thus they are sometimes called limiters or extrusion limiters. The shoes are typically segmented and, when the tool is set in a well, spaces between the expanded segments have been found to allow undesirable extrusion of the backer elements, at least in high pressure and high temperature wells. This tendency to extrude effectively sets the pressure and temperature limits for any given tool. Various improvements have been developed in ongoing efforts to prevent the extrusion of the packer elements between the segmented gaps and, while some have been effective to some extent, they have been complicated and expensive.
SUMMARY
[0005] The present invention provides a less complicated and expensive system of restraining the extrusion of the packer element by utilizing a simplified design to serve as a fixed extrusion limiter for a drillable tool. Additionally, the present invention does not suffer from the pressure and temperature limitations caused by the gaps in segmented limiters.
[0006] In one embodiment of the invention there is provided a downhole tool for use in a wellbore. The tool has a packer mandrel having a longitudinal axis. Disposed about the mandrel is an expandable sealing element, wherein the expandable sealing element is radially expandable outwardly from an unsealed position when the tool is in an unset position to a sealed position when the tool in a set position. In the sealed position, the expandable sealing element sealingly engages the wellbore. Additionally, the tool has a slip ring disposed about the mandrel and radially expandable outwardly from a disengaged position when the tool is in the unset position to an engaged position when the tool is in the set position, wherein the slip ring grippingly engages the wellbore in the engaged position. A slip wedge is disposed about the mandrel, having a radially outer surface containing a channel therein and an abutment end that abuts the expandable sealing element when the tool is in the set position. When the tool is moved from the unset position to the set position, the slip wedge interacts with the slip ring so as to expand the slip ring to its engaged position. A limiter ring is positioned in the channel of the slip wedge. When the tool is in the set position the limiter ring and the abutment end of the slip wedge act to retain the expandable sealing element and resist extrusion of the expandable sealing element.
[0007] In another embodiment of the invention there is provided a downhole tool for use in a wellbore. The tool has a packer mandrel having a longitudinal axis and an expandable sealing element disposed about the packer mandrel. The expandable sealing element is radially expandable outwardly from an unsealed position when the tool is in an unset position to a sealed position when the tool in a set position, and wherein the packer element assembly sealingly engages said wellbore in the sealed position. The tool also has a slip ring disposed about the mandrel. The slip ring is radially expandable outwardly from a disengaged position when the tool is in the unset position to an engaged position when the tool is in the set position. The slip ring grippingly engages the wellbore in the engaged position. A slip wedge is disposed about the mandrel. The slip wedge has a wedge portion having a generally conical shape with a first end having first outer radius and a second end having a second outer radius greater than said first outer radius. Additionally, the slip wedge has a back-up portion adjacent to the second end of the wedge portion. The back-up portion has a generally cylindrical shape with a third outer radius greater than the second outer radius and an abutment end that abuts the expandable sealing element when the tool is in the set position. The abutment end of the back-up portion acts to retain the expandable sealing element and resist extrusion of the expandable sealing element.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a cross-sectional side view of a packer apparatus in the unset position having a wedge and limiter ring in accordance with one embodiment of the present invention.
[0009] FIG. 2 is a cross-sectional side view of the packer apparatus of the embodiment of FIG. 1 in the set position.
[0010] FIG. 3 is a cross-sectional side view of the upper right section of the packer apparatus illustrated in FIG. 1 .
[0011] FIG. 4 is a cross-sectional side view of the lower right section of the packer apparatus illustrated in FIG. 1 .
[0012] FIG. 5 is a perspective view of limiter ring in accordance with an embodiment of the present invention.
[0013] FIG. 6 is a cross-sectional side view of a packer apparatus having a wedge in accordance with second embodiment of the present invention.
DETAILED DESCRIPTION
[0014] Referring now to FIGS. 1-4 , downhole tool, or downhole apparatus 10 is shown in an unset position 11 in a well 15 having a wellbore 20 . The wellbore 20 can be either a cased completion with a casing 22 cemented therein as shown in FIG. 1 or an openhole completion. Downhole apparatus 10 is shown in set position 13 in FIG. 2 . Casing 22 has an inner surface 24 . An annulus 26 is defined by casing 22 and downhole tool 10 . Downhole tool 10 has a packer mandrel 28 , and may be referred to as a bridge plug due to the downhole tool 10 having a plug 30 being pinned within packer mandrel 28 by radially oriented pins 32 . Plug 30 has a seal means 34 located between plug 30 and the internal diameter of packer mandrel 28 to prevent fluid flow therebetween. The overall downhole tool 10 structure, however, is adaptable to tools referred to as packers, which typically have at least one means for allowing fluid communication through the tool. Packers may therefore allow for the controlling of fluid passage through the tool by way of one or more valve mechanisms which may be integral to the packer body or which may be externally attached to the packer body. Such valve mechanisms are not shown in the drawings of the present document. Packer tools may be deployed in wellbores having casings or other such annular structure or geometry in which the tool may be set.
[0015] Packer mandrel 28 has an outer surface 36 , an inner surface 38 , and a longitudinal central axis, or longitudinal axial centerline 40 . Also, as referred to herein the term “radially” will refer to a radial direction perpendicular to the longitudinal axial centerline. An inner tube 42 is disposed in, and is pinned to, packer mandrel 28 to help support plug 30 .
[0016] Downhole tool 10 , which may also be referred to as packer apparatus 10 , includes the usage of a spacer ring 44 which is preferably secured to packer mandrel 28 by pins 46 . Spacer ring 44 provides an abutment, which serves to axially retain slip ring 48 which is positioned circumferentially about packer mandrel 28 . Slip ring 48 may be composed of slip segments positioned circumferentially around packer mandrel 28 in order to form the slip ring 48 . Slip retaining bands 50 serve to radially retain slip ring 48 in an initial circumferential position about packer mandrel 28 as well as slip wedge 52 . Bands 50 are made of a steel wire, a plastic material, or a composite material having the requisite characteristics of having sufficient strength to hold the slip ring 48 in place prior to actually setting the downhole tool 10 and to be easily drillable when the downhole tool 10 is to be removed from the wellbore 20 . Preferably, bands 50 are inexpensive and easily installed about slip ring 48 . Slip wedge 52 is initially positioned in a slidable relationship to, and partially underneath, slip ring 48 as shown in FIGS. 1 and 3 . Designs of slip ring 48 are described in U.S. Pat. No. 5,540,279, which is incorporated herein by reference.wwwww
[0017] Slip wedge 52 has a radially outer surface 54 containing a channel 56 therein. Additionally, slip wedge 52 has an abutment end 58 that abuts expandable sealing element 72 , located below slip wedge 52 . A limiter ring 60 is positioned in channel 56 . Limiter ring 60 has abutment end 62 that abuts expandable sealing element 72 . Limiter ring 60 is pressed into wedge 52 and can be held in place by frictional forces and/or adhesives. The limiter ring 60 can also serve to hold slip wedge 52 in place prior to setting the downhole tool.
[0018] As can be seen from FIG. 3 , slip wedge 52 is designed as a partial cone with a first outer radius R 1 at first end 64 and a second outer radius R 2 , wherein R 2 is greater than R 1 . In one embodiment, slip wedge 52 has the wedge portion 66 , preferably having a generally conical shape, and a tongue portion 67 , preferably having a generally cylindrical shape. Tongue portion 68 has an outer radius R 3 , which is less than R 2 . In this embodiment, limiter ring 60 has an inner radius that is substantially equal to R 3 and an outer radius R 4 that is greater than R 2 . In a second embodiment, illustrated in FIG. 6 , slip wedge 100 has a wedge portion 102 and a limiter portion or back-up portion 104 so that the limiter ring is an integral part of the slip wedge. In this second embodiment back-up portion 104 will preferably be generally cylindrical in shape and have an outer radius of R 4 .
[0019] Limiter ring 60 is design so that its outer surface 68 is close to inner surface 24 of casing 22 in order to minimize the gap between the two. Accordingly, the outer diameter of limiter ring 60 should be no more than 0.25 inch less than the inner diameter of the inner surface 24 to assure minimum extrusion of the expandable sealing element. In other words, outer radius R 4 should be no more than 0.125 inches less than the radius of inner surface 24 when the tool is in the set position. Additionally, the outer diameter of ring 60 should be no less than 0.125 inch less than the inner diameter of inner surface 24 to assure adequate clearance during insertion of the tool in the wellbore. In other words, radius R 4 should be no less than 0.0625 inch than the inner radius of inner surface 24 when the tool is in the unset position.
[0020] Limiter ring 60 can be a solid ring and applied to the downhole tool during assembly. In another embodiment, illustrated in FIG. 5 , limiter ring 60 has an expansion joint 70 , which allows the limiter ring to be installed after assembly of the downhole tool; that is after the spacer ring, slip rings, slip wedges and expandable sealing elements have been assembled on the packer mandrel. Expansion joint 70 can be a z-cut type joint.
[0021] Slip wedge 52 can be composed of composition material as is known in the art. Generally, limiter ring 60 can be made form any suitable material that will withstand the downhole use and yet can be readily cut or ground up by drilling with a drill bit. While limiter ring 60 may be composed of a similar material to slip wedge 52 , generally limiter ring 60 will be formed from a material having a higher wear resistance such as brass or zirconia ceramic. Additionally, non-metallic engineering grade plastics can be used for the limiter ring, such as composite materials or structural phenolic materials. A suitable phenolic materials are available from General Plastics & Rubber Company, Inc., 5727 Ledbetter, Houston, Tex. 77087-4095. Alternatively, structural phenolics available from commercial suppliers may be used.
[0022] Located below slip wedge 52 is a expandable sealing element 72 . The packer assembly of downhole tool 10 includes at least one such expandable sealing element, as shown in the figures, but may include two, three or more such expandable sealing elements. Expandable sealing element 72 has upper end 74 and lower end 76 . Expandable sealing element 72 has unset and set positions 78 ( FIGS. 1) and 80 ( FIG. 2 ) corresponding to the unset and set positions 11 and 13 , respectively, of downhole tool 10 . The expandable sealing element 72 is radially expandable from the unset position 78 to a set position 80 in response to the application of axial force on the expandable sealing element 72 . Preferably, in unset position 78 , expandable sealing element 72 has an unset radius that is less than the outer radius R 4 of limiter ring 60 . Also preferably, in set position 80 , expandable sealing element 72 has a set radius that is greater than outer radius R 4 of limiter ring 60 . In the set position 80 the expandable sealing element 72 engages the wellbore 20 to create a seal to prevent flow through annulus 26 .
[0023] Slip wedge 52 and limiter ring 60 are disposed at the upper end 74 of expandable sealing element 72 . There is a second slip wedge 82 and limiter ring 84 disposed at the lower end 76 of expandable sealing element 72 . Slip wedge 82 and limiter ring 84 are similar to slip wedge 52 and limiter ring 60 ; accordingly, like parts have been given the same reference numerals. As shown in FIGS. 1 , 2 and 3 upper end 74 of expandable sealing element 72 resides directly against the abutting ends of upper slip wedge 52 and upper limiter ring 60 . Additionally, lower end 76 of expandable sealing element 72 reside directly against lower slip wedge 82 and lower limiter ring 84 . Thus, as illustrated in FIG. 2 , by minimizing the gap between the outer surface 68 and the casing 22 , the upper and lower limiter rings retain the expandable sealing element in the set position and limit extrusion of the expandable sealing element; generally, this will be axial extrusion. Thus, the current limiter rings and slip wedges provide for a fixed extrusion limiter as opposed to the complex expanding extrusion limiter systems of prior art.
[0024] Located below slip wedge 82 is slip ring 86 . Slip wedge 82 and slip ring 86 are like slip wedge 52 and slip ring 48 . At the lowermost portion of downhole tool 10 is an angled portion, referred to as mule shoe 88 , secured to packer mandrel 28 by pin 90 . The lowermost portion of downhole tool 10 need not be mule shoe 88 but can be any type of section which will serve to terminate the structure of the downhole tool 10 or serve to connect the downhole tool 10 with other tools, a valve or tubing, etc. It will be appreciated by those in the art that pins 32 , 46 and 79 , if used at all, are preselected to have shear strengths that allow for the downhole tool 10 to be set and deployed and to withstand the forces expected to be encountered in the wellbore 20 during the operation of the downhole tool 10 .
[0025] Although the disclosed invention has been shown and described in detail with respect to a preferred embodiment, it will be understood by those skilled in the art that various changes in the form and detailed area may be made without departing from the spirit and scope of this invention as claimed. Thus, the present invention is well adapted to carry out the object and advantages mentioned as well as those which are inherent therein. While numerous changes may be made by those skilled in the art, such changes are encompassed within the spirit of this invention as defined by the appended claims. | The invention relates to an improved downhole tool apparatus for limiting the extrusion of a sealing elements in downhole tools. The apparatus provides for using a limiter ring or shoe located in a channel on the slip wedge so as to abut the sealing element. The limiter ring extends outward to the casing to minimize the gap through which the sealing element can extrude when the tool is in a set position. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a ladder caddy and more particularly pertains to supporting the tools of workmen in a convenient position on a ladder with a ladder caddy.
2. Description of the Prior Art
The use of devices of a wide variety, designs and configurations for supporting objects in a common location for transportation and use is known in the prior art. More specifically, devices of a wide variety, designs and configurations for supporting objects in a common location for transportation and use heretofore devised and utilized for the purpose of maintaining tools or other objects together by a wide variety of methods and apparatuses 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.
By way of example, U.S. Pat. No. Des. 304,084 to Meng which discloses a ladder caddy. U.S. Pat. No. 3,979,097 to Balne discloses a ladder caddy. U.S. Pat. No. 4,120,472 to Balne discloses a ladder caddy with rung catch means. U.S. Pat. No. 4,624,430 to Ehmke which discloses a ladder caddy. U.S. Pat. No. 5,123,620 to Bourne which discloses an accessory container for a ladder.
While these devices fulfill their respective, particular objective and requirements, the aforementioned patents do not describe a ladder caddy that holds tools and materials in a position for ready access when using a ladder.
In this respect, the ladder caddy according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of supporting the tools of workmen in a convenient position on a ladder.
Therefore, it can be appreciated that there exists a continuing need for new and improved ladder caddy which can be used for supporting the tools of workmen in a convenient position on a ladder. In this regard, the present invention substantially fulfills this need.
SUMMARY OF THE INVENTION
In the view of the foregoing disadvantages inherent in the known types of devices of a wide variety, designs and configurations for supporting objects in a common location for transportation and use now present in the prior art, the present invention provides an improved ladder caddy. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved ladder caddy and method which has all the advantages of the prior art and none of the disadvantages.
To attain this, the present invention essentially comprises, in combination, a housing. The housing includes a generally rectangular vertical interior side wall having long parallel horizontal upper and lower edges and short vertical end edges interconnected therebetween. The housing includes a generally rectangular vertical exterior side wall offset from and positioned in parallel with the interior side wall and with the exterior side wall having long parallel horizontal upper and lower edges and short vertical end edges interconnected therebetween and with the end edges of the exterior wall being shorter than the end edges of the interior wall. The housing includes a pair of generally rectangular vertical end walls each having parallel horizontal upper and lower edges and parallel vertical end edges interconnected therebetween. Each end wall has one end edge coupled with a separate end edge of the exterior side wall such that the lower edges of the interior side wall, exterior side wall, and end walls are positioned in a first common plane and the upper edges of the end walls and exterior side wall are positioned in a second parallel common plane located above the first common plane and beneath the upper edge of the interior side wall. Each end wall has its other end edge coupled to the interior side wall. The housing includes a generally rectangular horizontal lower wall positioned in the first common plane and having long parallel horizontal interior and exterior edges and short parallel horizontal end edges and with the end edges thereof coupled with the lower edges of the end walls, the exterior edge thereof coupled with the lower edge of the exterior side wall, and the interior edge thereof coupled with the lower edge of the interior side wall to form a container with a box-shaped hollow interior portion. The housing includes a generally rectangular vertical dividing wall having parallel horizontal upper and lower edges and parallel vertical interior and exterior edges interconnected therebetween with the dividing wall disposed within the container with the exterior edge thereof coupled to the exterior side wall, the interior edge thereof coupled to the interior side wall, the lower edge thereof coupled to the lower wall, and the upper edge thereof positioned within the second common plane. The dividing wall thereby creates two equally-sized bins within the container for holding tools. Lastly, the housing includes an upstanding central region extended from the upper edge of the interior wall with the central region having an oblong recess formed therethrough to create a carrying handle.
A pair of C-shaped brackets are provided. Each bracket has an exterior wall pivotally coupled to the interior side wall adjacent to one of its end edges. Each bracket further includes an interiorly extending region adapted to be secured to a separate leg of a ladder.
A horizontally extending first plate is included and secured to and extended outwards from a central extent of the interior side wall above the container. The first plate had a plurality of circular apertures therethrough for receiving screwdrivers and a plurality of elongated slots therethrough for receiving pliers and cutters. A horizontally extending second plate is also included and secured to and extended outwards from the interior side wall. The second plate has an elongated recess formed thereon with an aperture extending centrally therethrough to create a hammer holder for receiving a hammer. An L-shaped wall is also included and has long upper and lower L-shaped edges and short vertical end edges with one end edge coupled to the end edge of the interior side wall and the other end edge coupled to the end wall to create a drill pocket located on a side of the container opposite the hammer holder for receiving a drill. Lastly, a pair of spaced parallel feet are included and extend downwardly from the lower wall of the container for allowing the ladder caddy to be set on a recipient surface. The ladder caddy is fabricated of a high-impact resistant plastic material.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new and improved ladder caddy which has all the advantages of the prior art devices of a wide variety, designs and configurations for supporting objects in a common location for transportation and use and none of the disadvantages.
It is another object of the present invention to provide a new and improved ladder caddy which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new and improved ladder caddy which is of durable and reliable construction.
An even further object of the present invention is to provide a new and improved ladder caddy which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such a ladder caddy economically available to the buying public.
Still yet another object of the present invention is to provide a new and improved ladder caddy which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Even still another object of the present invention is to provide a new and improved ladder caddy for supporting the tools of workmen in a convenient position on a ladder.
Lastly, it is an object of the present invention to provide a new and improved ladder caddy comprising a housing formed with a generally vertical side wall, container means coupled to a central extent of the side wall for holding tools therein, and handle means coupled to and extended upwards from the side wall; and coupling means for removably coupling the side wall to the legs of a ladder.
These together with other objects of the invention, along with 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 the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a side-elevational view of the preferred embodiment of the new and improved ladder caddy constructed in accordance with the principles of the present invention.
FIG. 2 is an enlarged side-elevational view similar to FIG. 1 but with parts shown in cross-section.
FIG. 3 is a top view of the device illustrated in FIGS. 1 and 2.
FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG. 2.
FIG. 5 is a cross-sectional view taken along the line 5--5 of FIG. 2.
FIG. 6 is a cross-sectional view taken along the line 6--6 of FIG. 2.
The same reference numerals refer to the same parts through the various Figures.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular, to FIG. 1 thereof, the preferred embodiment of the new and improved ladder caddy embodying the principles and concepts of the present invention and generally designated by the reference number 10 will be described.
The present invention is comprised of a plurality of components. In their broadest context, such components include a housing, brackets, plates, and feet. Such components are individually configured and correlated with respect to each other to provide the intended function of holding tools and related materials at a position for ready access when using a ladder.
Specifically, the ladder caddy includes a housing 12. The housing includes a generally rectangular and vertically positioned interior side wall 14. The interior side wall is rigid in structure and has long parallel horizontal upper and lower edges 16, 18 and short vertical end edges 20 interconnected therebetween. The housing also includes a generally rectangular and vertically positioned exterior side wall 22. The exterior side wall is offset from and positioned in parallel with the interior side wall. The exterior side wall is rigid in structure and has long parallel horizontal upper and lower edges 24, 26 and short vertical end edges 28 interconnected therebetween. The end edges of the exterior wall are shorter than the end edges of the interior wall. Furthermore, the long edges of the exterior wall are shorter than the long edges of the interior wall. The housing also includes a pair of generally rectangular and vertically positioned end walls 30. The end walls are aligned in parallel and offset from each other. Each end wall is rigid in structure and has parallel horizontal upper and lower edges and parallel vertical end edges interconnected therebetween. Each end wall has one end edge coupled with a separate end edge of the exterior side wall such that the lower edges of the interior side wall, exterior side wall, and end walls are positioned in a first common plane. Furthermore, this coupling ensures that the upper edges of the end walls and the exterior side wall are positioned in a second parallel common plane located above the first common plane and beneath the upper edge of the interior side wall. Each end wall has its other end edge coupled to the interior side wall. The housing also includes a generally rectangular and horizontally positioned lower wall 40. This lower wall is positioned in the first common plane and is bounded by the end walls and exterior side wall. The lower wall is rigid in structure and has long parallel horizontal interior and exterior edges and short parallel horizontal end edges interconnected therebetween. The end edges thereof are coupled with the lower edges of the end walls. The exterior edge of the lower wall is coupled with the lower edge of the exterior side wall. Furthermore, the interior edge of the lower wall is coupled with the lower edge of the interior side wall. This coupling of the edges with the edges of the end walls and interior and exterior side walls forms a container 50 having a box-shaped hollow interior portion with an open top. The housing also includes a generally rectangular and vertically positioned dividing wall 54. The dividing wall is rigid in structure and has parallel horizontal upper and lower edges and parallel vertical interior and exterior edges interconnected therebetween. The dividing wall is disposed within the container with its exterior edge coupled to the exterior side wall, its interior edge coupled to the interior side wall, and its lower edge coupled to the lower wall such that its upper edge is positioned within the second common plane. This coupling thereby creates two equally-sized bins 56 within the container. These bins are used for holding tools, materials, and the like. The housing also includes an upstanding central region 58. This central region is extended from the upper edge of the interior wall. The central region has an oblong recess 60 formed therethrough to create a carrying handle for allowing a user a firm grip of the ladder caddy.
A pair of C-shaped brackets 70 are also provided. Each bracket has an exterior wall 72 pivotally coupled to the interior side wall at a location adjacent to one of its end edges. This pivotal coupling is performed with a pin 74. Each bracket further has an interiorly extended region 76. This extending region is adapted to be secured to a separate leg 78 of a ladder for holding the housing in a stationary position.
The present invention also includes a horizontally extended first plate 80. The first plate is rigid in structure and secured to and extended outwards from a central extent of the interior side wall at a location above the container 50. The first plate has a plurality of circular apertures 82 formed therethrough for receiving screwdrivers. The first plate also has a plurality of elongated slots 84 formed therethrough for receiving pliers 86, cutters 88, and the like.
Also provided is a horizontally extending second plate 90. The second plate is rigid in structure and secured to and extended outwards from the interior side wall. The second plate has an elongated recess 92 formed thereon with an aperture 94 extending centrally therethrough to create a hammer holder 96. The hammer holder is adapted for receiving a hammer 98.
Also provided is an L-shaped wall 100. This L-shaped wall has long upper and lower L-shaped edges and short vertical end edges. One end edge of the L-shaped wall is coupled to the end edge of the interior side wall. The other end edge of the L-shaped wall is coupled to the end wall. This coupling creates a drill pocket 102 located on a side of the container opposite the hammer holder 96. The drill pocket is used for receiving a drill 104.
To support the invention on a recipient surface, a pair of spaced parallel feet 110 are provided. The feet are extended downwardly from the lower wall of the container 50. Thus, the ladder caddy can be used in a stand-alone mode on a recipient surface with support provided by its feet or in a hanging mode with support provided through its brackets.
The present invention is an adaptation of the common carpenter pouch for use on a ladder as a tool and material organizer. It hooks over the ladder legs when the ladder is in an open position for storage of drills, miscellaneous tools, and nails, screws, and the like. The present invention is made from plastic, metal, leather, or a combination thereof. In the preferred embodiment, the ladder caddy is fabricated of a high-impact resistant plastic material. The length of the present invention is about 15 inches and its height is about 6 to 8 inches. The present invention is especially useful to carpenters, plumbers, electricians and do-it-yourselfers. The present invention resolves the problem of positioning tools and materials in a position for ready access when using a ladder.
As to the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and the manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modification and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modification and equivalents may be resorted to, falling within the scope of the invention. | A ladder caddy comprising a housing formed with a generally vertical side wall, a container mechanism coupled to a central extent of the side wall for holding tools therein, and a handle mechanism coupled to and extended upwards from the side wall; and a coupling mechanism for removably coupling the side wall to the legs of a ladder. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a tray carton erecting machine and, more particularly, to an end panel folding and sealing apparatus which seals the end panels and end flaps of the tray cartons together to complete the erection of the tray carton from its blank.
Tray carton machines which erect tray blanks about articles to be packaged in the tray cartons are used extensively in the soft drink and beer industry to package either sets of individual beverage cans, or pair of twelve-pack cartons. These tray carton machines typcally package up to 100 cartons per minute and normally employ static folding bars for folding the end panels of the trays against the end flaps and holding them together while the glue previously applied between the end flaps and panels sets. Some of these machines, such as the one disclosed in U.S. Pat. No. 3,504,478 also employ an auxiliary end panel sealer which is actuated when the machine is shut down to complete the folding and sealing of the end panels and flaps of the tray carton then in the folding and sealing station.
Tray carton machines which employ the static folding bars encounter a problem. The static bars which both fold and press the end panels against the end flaps to complete the formation of the trays exert a drag on the end panels. This causes at least some of the tray cartons to be formed such that the end panels do not line up properly with the end flaps and side panels. The tray cartons are out of square. This problem is not only aesthetic but the projecting portions of the panels can catch on other trays or objects and the handling of these trays can be a problem.
Tray carton machines such as the one disclosed in U.S. Pat. No. 3,504,478 which utilize an auxiliary end panel sealer that is pneumatically operated can present additional problems. If the pneumatic system malfunctions the tray then in the folding and sealing station will not be sealed. If the problem is observed the tray can be removed from the machine. Otherwise the tray carton comes apart after being discharged from the machine.
The tray carton machine of the present invention is provided with a unique end panel folding and tray sealing assembly. The static end panel folding bar and the need for an auxliary end flap sealer is eliminated by the mechanism of the present invention.
The mechanism for folding the tray end panels and pressing the end panels against the tray end flaps includes a pair of folding plates mounted within the folding and sealing station adjacent to and on opposite sides of the tray conveyor. Each folding plate is rotatably attached at its lower ends of crank arms of a pair of cranks. The cranks are spaced from each other with one crank being located a distance downstream from the other crank, less than the length of the folding plate. The crank arms of the cranks extend parallel to each other and are equal in length. Thus as the cranks are rotated in unison, the folding plates, which are in contact with the tray end panels during the upper half of their cycles, move in the downstream direction as the plates are being raised and lowered to fold the end panels and press the end panels against the end flaps. The downstream movement of the folding plates during the folding of the end panels and the sealing of the tray substantially eliminates or reduces drag by the folding plates on the end panels. Thus the tray carton machine of the present invention can form trays which are insquare and at speeds of over 100 cartons per minute.
Another advantage of the present invention is the elimination of an auxiliary end panel folding mechanism. The crank mechanisms are driven by drive trains which not only synchronize the cycles of the folding plates with the movement of the tray conveyor but also stop the folding plates at the uppermost point of their cycles under a normal shutdown. The end panels of the tray in the station are pressed and held against the end flaps to seal the tray and no auxiliary mechanism or pneumatic controls are required to effect the sealing operation.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objectives and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a schematic plan view of a tray carton machine using the present invention;
FIG. 2 is a cross-sectional elevation view in the gluing and sealing station illustrating the folding and sealing mechanism on the loading side of the machine with the folding plate in its upstream position at the beginning of a folding and sealing cycle;
FIGS. 3 and 4 are cross-sectional views of the gluing and sealing station, looking upstream from the discharge station, at the beginning of the folding and sealing cycle and midway through the folding and sealing cycle respectively;
FIGS. 5-8 are views of the folding and sealing mechanism on the loading side of the machine illustrating the position of the folding plate at 90° intervals of rotation of the cranks; and
FIGS. 9-13 are schematic views illustrating the steps of completing the formation of a tray carton after it has been loaded with articles.
DETAILED DESCRIPTION OF THE INVENTION
The schematic plan view of the tray carton machine 2 illustrates the typical stations of such a machine. The tray carton machine 2 includes a tray blank hopper and feed system 4, an article loading station 6, a gluing and sealing station 8 and a discharge station 10 where the trays with the articles packaged therein are removed for storage or shipment.
Each tray carton 12 includes a bottom panel 14, a pair of side panels 16 and 18, a pair of end panels 20, 22 and end flaps 24, 26, 28 and 30. The side panels and end panels are hingedly joined to the bottom panel along score lines and the end flaps are hingedly joined to the ends of the side panels along score lines.
A tray carton conveyor 32 comprising pairs of tray carrier lugs 34 joined by drive chains 36 extends from the tray blank hopper and feed system 4 through the discharge station 10. As the pairs of lugs 34 travel downstream through the machine carrying the tray cartons 12, the lugs travel over and adjacent the lateral edges of a bed plate 38 which also extends from the tray blank hopper and feed system 4 through the discharge station 10. The adjacent lugs 34 are spaced a distance equal to the width of the tray cartons 12 which they transport through the machine.
The tray blank hopper and feed system 4 can be one of several such systems known in the art such as the tray feed system disclosed in U.S. Pat. No. 4,034,658, the disclosure of which is hereby incorporated by reference. The function of the tray hopper and feed system is to supply tray blanks to the conveyor 32 so that the tray blanks can be erected, loaded and sealed into tray cartons.
As the tray blanks are loaded onto the tray carton conveyor 32, the tray blanks are partially erected as shown in FIG. 9 for the loading operation by conventional folding bars and tucking fingers normally used for such operations. The end panels 20 and 22 are erected and held upright by the lugs 34. The end panels are disposed under the fold down bars 40 (only one is shown) which extend from the tray hopper and feed system through the loading station. The fold down bars 40 are mounted on opposite sides of the bed plate 38 below the horizontal plane of the bed plate. The bars 40 are adjacent to but spaced laterally from the bed plate and are inclined downward and outward to hold the end panels down. The end flaps 24 and 26 on the loading side of the tray carton are folded outward to extend away from each other and held in that position between lugs 34 and the raised bars 42 of the basket chain conveyor 44. The end flaps 28 and 30 on the opposite side of the tray carton are folded inward toward each other and held in that position by flap retaining rod 46. The flap retaining rod extends from the tray hopper and feed system to the gluing and sealing station. The rod is mounted adjacent the side of the bed plate 38 at a height about half the height of the end flaps above the horizontal plane of the bed plate 38.
The articles to be packaged in the tray cartons are loaded into the partially erected cartons at the article loading statin 6. The articles to be packaged are supplied to the loading station 6 by an infeed conveyor 48. The articles to be packaged in the tray carton typically comprise one of the following: twenty-four individual cans, four six-packs of cans or bottles, or two twelve-packs of cans or bottles.
The infeed conveyor delivers the articles to be packaged onto the basket chain conveyor 44. The basket chain conveyor 44 is located adjacent, runs parallel to, and at the same speed as the main conveyor 32. The basket chain conveyor 44 comprises a plurality of sections 50 made up of slats which are separated by the pairs of raised bars 42. The raised bars 42 are aligned with the lugs 34 of the tray carton conveyor 32 and function not only to retain the articles in place on the basket chain conveyor but also, as mentioned above, to retain the end flaps 24 and 26 in the open position. The end flaps 24 and 26 are held between the lugs 34 and raised bars 42 as the tray cartons pass through the loading station 6. Each section 50 of the conveyor 44 carries the articles to be deposited within one tray carton 12.
The articles to be packaged in the tray cartons 12 are loaded into the tray cartons by a pusher plate conveyor 52. The pusher plate conveyor 52 extends at an angle from the infeed conveyor 48, converges in the downstream direction toward the tray carton conveyor 32, and ends adjacent the tray carton conveyor 32. The pusher plate conveyor 52 includes a series of chain connected pusher plates 54 having article contact surfaces 56 extending parallel to the direction of travel of both the basket chain conveyor 44 and the tray carton conveyor 32. There are typically two pusher plates 54 for each section 50 of the basket chain conveyor. As the pusher plate conveyor 52 advances in the downstream direction each pair of pusher plates 54 contact the articles carried in the sections 50 and push them in a direction perpendicular to the direction of travel of both the basket chain conveyor 44 and the tray carton conveyor 32. In this manner the articles are pushed from each section 50 of the basket chain conveyor onto the bottom panel 14 of the tray carton 12 being carried by the tray carton conveyor 32 adjacent that particular basket chain conveyor section 50.
The partially erected tray cartons with the articles loaded therein are then conveyed by the tray carton conveyor 32 from the loading station 6 to the gluing and sealing station 8. There the erection of the tray is completed and the tray is sealed to complete the formation of the tray.
The gluing and sealing station 8 as best illustrated in FIGS. 2, 3 and 4, includes an end flap folding rod 58, an end flap tucking finger 60, a pair of end panel folding bars 62, a pair of end panel support rods 64, two pair of glue guns 66 and 68, an electronic eye 70 and a pair of end panel folding and sealing mechanisms 72 and 74.
The end flap folding rod 58 for folding the leading end flap 24 inward and retaining the leading end flap 24 in place is a static bar mounted just upstream of the end panel folding and sealing mechanism 72. The rod 58 is adjacent but not over the tray loading side of the bed plate 38. The height of the rod 58 above the horizontal plane of the bed plate 38 is equal to about one half of the height of the end flap 24. The rod 58 folds end flap 24 into the position illustrated in FIG. 10.
The end flap tucking finger 60 for folding the trailing end flap 26 inward is illustrated in FIGS. 1 and 2. The tucking finger 60 rotates clockwise and its rotation is synchronized with the movement of the tray carton conveyor 32 so that it folds the trailing end flap 26 in a downstream direction and holds the trailing end flap in place until the flap passes behind static rod 58 which retains it in place until the end panel 20 is folded upward. See FIG. 11.
The pair of end panel folding bars 62 are mounted directly across from each other just upstream from the end panel folding and sealing mechanisms 72 and 74 and adjacent the sides of the bed plate 38. The panel folding bars 62 are triangular in shape with upper surfaces that are inclined upwardly in the downstream direction. As the end panels 20 and 22 pass from beneath the fold down bars 40, the undersides of the end panels are engaged by the folding bars 62 and raised by the folding bars to an angle of about 20° to 30° above the horizontal. FIG. 11 illustrates the tray carton with the end panels partially raised by the folding bars as the leading ends of the end panels ride up on the folding bars.
Once the end panels 20 and 22 are raised by the folding bars 62, the panels pass downstream onto the end panel support rods 64 as the tray cartons are moved through the gluing and sealing station by the tray carton conveyor 32. The panel support rods 64 are mounted directly opposite each other on either side of the bed plate 38. The panel support rods 64 extend horizontally at a height above the plane of the bed plate 38 sufficient to support the panels at the angles set by the folding bars 62. The rods 64 are spaced laterally from the bed plate 38 distances sufficient to permit the folding plates 76 and 78 of the folding and sealing mechanisms to pass between the panel support rods 64 and the bed plate 38.
As shown in FIG. 1, the two pairs of glue guns 66 and 68 are mounted on either side of the bed plate 38 and are actuated by an electronic eye 70 to simultaneously apply glue to both end panels 20 and 22. The spacing between the glue guns of each pair is such that the beads of glue applied by the guns are located on the leading and trailing ends of the end panels 20 and 22 to coincide with the end flaps when the end panels are folded. Immediately after the glue beads are applied the end panels 20 and 22 are engaged by the end panel folding and sealing mechanisms 72 and 74 which complete the folding and sealing of the end panels. FIGS. 3 and 12 show the tray carton as the glue is being applied and prior to the contact between the end panels and the folding plates 76 and 78.
As shown in FIG. 1 the end panel folding and sealing mechanisms 72 and 74 are located on either side of and adjacent to the bed plate 38 just downstream from the panel folding bars 62 and just upstream from the discharge station 10. As illustrated in FIGS. 2-4 the end panel folding and sealing mechanisms 72 and 74 each includes a folding plate 76 and 78 respectively and a pair of cranks 80, 82 and 84, 86.
The folding plates 76 and 78 are about equal in length to the width of the tray cartons. The main portions of the folding plates 76 and 78 are vertical and flat. However, the upper ends of the folding plates 76 and 78 are inclined outwardly away from the bed plate so that the initial contact between the folding plates and the tray carton end panels 20 and 22 does not damage the end panels. The upper ends of the folding plates have cut out portions 88 as illustrated in FIG. 2, to provide clearance for the glue guns as the folding plates pass through the upper half of their cycles.
As shown in FIG. 2 the folding plate 76 is rotatably mounted adjacent its lower upstream and downstream ends to the crank arms of the cranks 80 and 82. As shown in FIG. 1, the folding plate 78 is rotatably mounted adjacent its lower downstream and upstream ends to crank arms of of the cranks 84 and 86. The crank arms of all of the cranks are of equal length and extend parallel to each other. The rotations of the cranks 80, 82, 84 and 86 are synchronized with each other so that the folding plates 76 and 78 move in unison. The cranks 80 and 82 of the folding and sealing mechanism 72 illustrated in FIG. 2 rotate in a counter clockwise direction. Of course the cranks 84 and 86 of the folding and sealing mechanism 74 opposite the mechanism illustrated in FIG. 2 rotate in a clockwise direction. While FIGS. 5 through 8 illustrate the folding and return cycle for folding and sealing mechanism 72 at 90° intervals, it is to be understood that the folding and sealing mechanism 74 would be in corresponding positions at the same intervals of its cycle.
The rotations of the cranks 80, 82, 84 and 86 and accordingly the movements of folding plates 76 and 78 are also synchronized with the movement of the tray carton conveyor 32 so that the folding plates first contact the tray end panels 20 and 22 at the point of their cycles illustrated in FIGS. 2, 3 and 5. As the tray passes through the gluing and sealing station the folding plates 76 and 78 move upward and downstream. When the tray carton is midway through the gluing and sealing station 8 the folding plates 76 and 78 have moved to the uppermost part of their cycles as illustrated in FIGS. 4 and 6. As the leading part of the tray carton starts to pass between the compression bars 90 of the discharge station, the folding plates move from their uppermost position as illustrated in FIGS. 4 and 6 to their most downstream position as illustrated in FIG. 7. At the point the folding plates 76 and 78 reach their most downstream position the tray carton 12 is completely released from the folding plates and the end panels are only engaged by the compression bars 90 of the discharge station. FIG. 8 illustrates the location of the folding plates midway through the return or upstream portion of their cycles. In another 90° of movement the folding plates are again at the beginning of their folding cycle and about to engage the end panel of the next tray.
The compression bars 90 of the discharge station are mounted adjacent to the sides of but not over the bed plate 38. The compression bars extend from a height just above the bed plate to a height about equal to the height of the end panels. The compression bars are spaced from each other a distance such that the bars engage the end panels of the trays and retain pressure on the end panels. From the discharge station the trays with the articles therein are shipped or put into storage.
The operation of the folding and sealing station will now be described in detail.
After the tray cartons pass the loading station and before they are glued and sealed at the sealing station, the end flaps 24 and 26 on the loading side of the tray cartons 12 must be folded into position. As the end flaps 24 and 26 are released by the lugs 34 and raised bars 42 they spring outward. The leading end flap 24 is then contacted by the static flap folding rod 58 which folds the end flap 24 into place. The trailing end flap 26 is then folded into place by the rotating tucking finger 60 which holds the flap 26 in place until it passes behind the flap folding rod 58.
With the end flaps 24, 26, 28 and 30 in place, as the end panels 20 and 22 emerge from beneath the fold down bars 40 the panels are engaged by the upwardly inclined surfaces of the folding bars 62. The folding bars 62 raise the end panels slightly above the horizontal and the end panels pass onto and are supported by end panel support rods 64. Just before the end panels 20 and 22 are engaged by the folding plates 76 and 78, the glue guns 66 and 68 are actuated by the electronic eye 70 and deposit beads of glue at the leading and trailing ends of the end panels in alignment with the end flaps.
The end panels are then folded upward into place by the folding plates 76 and 78 which are moving in an upward and downstream direction as they make initial contact with the end panels. The folding plates as they pass through the upper half of their cycles not only fold the end panels 20 and 22 into position but press the end panels against the end flaps 24, 26, 28 and 30 as the glue at least partially sets. The articles in the tray provide a backing so that the end flaps and end panels are pressed together between the articles and the folding plates. As the folding plates pass through the last part of the upper portion of their cycle, the folding plates still move downstream but they also move downward releasing the tray cartons 12 to the compression bars 90 of the discharge station 10 which engage the leading portions of the tray cartons while the trailing portions of the tray cartons are still gripped between the folding plates. The glued and sealed tray, as illustrated in FIG. 13, is then ready for storage or shipment. The articles have been omitted from the drawings so that the operation of the machine and the formation of the tray carton could be better illustrated. | In a machine for erecting tray cartons about one or more articles such as pairs of twelve pack beverage cartons, an end panel folding and sealing assembly is provided with folding plates that move with the tray carton in the downstream direction as the plates fold and hold the tray end panels against the tray end flaps while the glue sets to adhesively bond the end panels and flaps together. | 1 |
BACKGROUND AND SUMMARY OF THE INVENTION
The instant invention relates to a process to piece to a spinning device following yarn breakage, using a pneumatic torsion device with an injection component which is separated from a torsion component by a gap open to the atmosphere, in which the yarn is threaded into the pneumatic torsion device from the outlet side, with the help of negative pressure, and to a device to carry out said process.
According to a known process, the yarn is sucked from the side opposite to the draw-off rolls through the torsion nozzle brought into threading position (see German published application No. 3,411,577 corresponding with U.S. Pat. Nos. 4,550,560 and 3,413,894 corresponding with U.S. Pat. No. 4,545,193). In this case for spinning only a single nozzle is used which not in every case leads to acceptable results with respect to the spun yarn.
For the production of bulky yarn it is also already known to provide an injector nozzle in front of the torsion nozzle, those two nozzles being arranged one relative to the other in such a manner that a gap exists between them (See German published application No. 3,237,990). Since air enters through this gap, strong negative pressure is required in the two nozzles for the threading of the yarn.
It is therefore the object of the instant invention to create a process and a device which make it possible to thread the yarn into the nozzles, separated from each other by an air gap, in a simple manner and with low air consumption.
This object is achieved according to the invention in that the gap is sealed against the atmosphere before threading of the yarn, the yarn is then threaded into the torsion element in opposite direction to the draw-off direction and the gap is laid open again, at the latest at the beginning of draw-off of the pieced yarn. By sealingly closing the gap before threading, the negative pressure applied to the mouth which constitutes the inlet side during normal spinning of the torsion element can exert its full force at the mouth of the torsion element which constitutes the outlet side during normal spinning. The intensity is thus unaffected by extraneous air penetrating through the gap. With the gap being covered, the yarn is again threaded into the torsion element and is combined with the fiber sliver or roving being fed to the machine. The gap is laid open before or during piecing, at the latest when draw-off of the pieced yarn begins, so that the withdrawal of the yarn is not affected.
In a simple embodiment of the process of the invention, sealing of the gap can be effected by covering it. In this case it is possible to utilize the movement of the torsion element from its spinning position into a threading position and to seal the gap through the transfer of the torsion element into its threading position. However, an axial movement of the injector nozzle and/or of the torsion nozzle can also be produced for this purpose, so that the gap is closed by the relative axial movement of injector nozzle and torsion nozzle.
To carry out the described process the invention provides for the utilization of a sealing device which can be associated to the gap between injector nozzle and torsion nozzle during the threading phase, so as to prevent penetration of extraneous air into the interior of the torsion nozzle.
The sealing device is advantageously formed as a screen which can be associated to the gap. In an advantageous embodiment of this device according to invention, the torsion element is provided with an elastic element by means of which it is held against a stop determining the spinning position, while the screen associated to the gap is also used as a driving device by means of which the torsion element can be brought into the threading position. The torsion element can be supported pivotably and can be applied sealingly against the screen through swivelling around its swivelling axle.
The screen can take various forms and can be associated to the gap in different ways. For example, a stationary screen can be provided, whereby the gap can be associated to it for sealing closure through the movement of the torsion element from its spinning position into its threading position.
Sealing of the gap is also possible if the torsion nozzle and the injector nozzle can be brought into contact with each other through axial shifting of at least one of these two nozzles so that the gap between the two nozzles is closed.
Another advantageous embodiment of the object of the invention provides for the torsion nozzle and/or the injector nozzle to be equipped with a sleeve-like screen which can be brought by axial shifting into a position covering the gap between torsion element and injector nozzle.
In an especially simplified and advantageous embodiment of the device according to invention, the suction pipe can be pressed against the inlet side of the torsion element in such a manner that the gap between the injector nozzle and the torsion nozzle is closed. Depending upon the design of the object of the invention, the suction pipe either presses the elastically supported injector nozzle against the torsion nozzle or pushes the sleeve-like, also elastically supported screen to a point beyond the gap between injector nozzle and torsion nozzle.
By means of the process of the invention and of the device made in accordance with the invention, threading of the yarn into the torsion element can be carried out in a simple manner with the help of relatively little negative pressure and therefore economically. Since the aspiration of extraneous air through the gap between injector nozzle and torsion nozzle is eliminated, the threading negative pressure is exerted with full intensity upon the outlet side (during normal spinning) of the torsion element.
BRIEF DESCRIPTION OF THE DRAWINGS
Examples of embodiments are illustrated in further detail through the drawings, in which:
FIG. 1 is a schematic front view of a spinning device according to the invention, in threading position;
FIG. 2 is a top view and partial section of a special design of the device shown in FIG. 1, in spinning or threading position, respectively;
FIG. 3 is a top view of a variant of the spinning device shown in FIG. 2;
FIGS. 4 and 5 are longitudinal sections of a torsion element with axially mobile injector nozzle in spinning and in threading position, respectively
FIG. 6 is a variation of the torsion element shown in FIGS. 4 and 5, in spinning position.
Repeat use of reference characters throughout the drawings and specification is intended to represent same or analogous features or aspects of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The spinning device described first through FIG. 1 has as its essential elements a drafting mechanism 2, a torsion element 3, a draw-off device 4, a winding device 5, and a threading device 6.
In accordance with FIG. 1 the drafting mechanism 2 has four pairs of rolls, with rolls 20 and 200, 21 and 210, 22 and 220 as well as 23 and 230, whereby the rolls 22, 220 are equipped with small belts 222. Compressors 201, 211, and 221 are installed in front of the rolls 20, 200, between the rolls 21, 210 and 20, 200 and between the rolls 21, 210 and 22, 220, respectively. A clamping device 202 or 212 for the roving is furthermore installed in front of the rolls 20, 200 and in front of the rolls 21, 210 respectively.
As can be seen from FIGS. 4 to 6, the torsion element 3 is equipped with an injector nozzle 30 as well as with a torsion nozzle 31 which are provided with compressed air openings 300 and 310 respectively to admit compressed air. The injector nozzle 30 and the torsion nozzle 31 are installed in a holding device 32 which is provided with ring channels 320 and 321 with which the compressed air openings 300 or 310 are connected. The ring channels 320 and 321 are connected to a source of negative pressure (not shown) via lines 322 and 323.
The injector nozzle 30 and the torsion nozzle 31 are installed at an axial distance from each other so that a gap 33 remains between them. This gap 33 between the injector nozzle 30 and the torsion nozzle 31 is connected to the atmosphere via a gap 34 in the holding device 32.
The draw-off device 4, as shown in FIG. 1, is equipped in the usual manner with a driven draw-off roll 40 and with a pressure roll 41 interacting elastically with said draw-off roll 40.
The winding device 5 is equipped with a driven winding roll 50 which drives the conventionally supported bobbin 51.
Other conventional means such as a yarn oscillating device, yarn tension compensating bar, yarn monitor etc. have not been shown in FIG. 1 for the sake of simplification.
A suction pipe 60 and a sealing device 61, by means of which the gap 33 between the injector nozzle 30 and the torsion nozzle 31 can be closed sealingly against the atmosphere, are shown in FIG. 1 as the most essential elements of the threading device 6.
The operation of the device, the composition of which is described above, is explained below:
During undisturbed spinning operation, a fiber sliver or roving 1 is fed to the drafting mechanism 2, is stretched by said drafting mechanism 2 to the desired thickness for the spun yarn 10, and is then fed to the torsion element 3. In this process the fiber ends of the outer fibers spread away from the fed small sliver. By means of the compressed air which is fed to it, the torsion element 3 causes the free fiber ends of the small sliver being fed to the injector nozzle 30 to loop around the yarn core. The yarn core is given a certain amount of false twist, which is again undone to a great extent afterwards, in the torsion element 3. In the course of false twist and undoing thereof, the fiber ends are incorporated into the yarn core and thus ensure that the spun yarn 10 will be of desired strength.
The spun yarn 10 is drawn off by the draw-off device 4 from the torsion element 3 and is fed to the winding device 5 to be wound on the bobbin 51.
If the yarn breaks, a signal is given in a known manner by a yarn monitor (not shown), causing the two clamping devices 202 and 212 for the roving to be activated. The roving 1 is thereby stopped in front of the rolls 20, 200 and 21, 210. The portion of the roving following these rolls is separated from the stopped portion of the roving through continued running of the rolls 22, 220 and 23, 230 and is fed to a suction mechanism (not shown) so that clogging of the torsion element 3 by fiber material which is no longer drawn off from said torsion element 3 is avoided.
For piecing, the torsion element 3 is brought from its spinning position I into its threading position II. The holding device 32 comes to lie against stop 61 in such a manner that the latter covers the gap 34 which extends merely over a portion of the circumference of said holding device 32.
The yarn end which is on bobbin 51 is located and is drawn off from said bobbin 51 through reverse rotation of said bobbin 51 and removal by suction. The yarn end is then presented to the side of the torsion element 3 which constitutes its outlet side 311 during normal spinning operation. The suction pipe 6 is furthermore brought before the side of torsion element 3 which constitutes its inlet side 301 during normal spinning operation.
Negative pressure is now produced inside suction pipe 6 while the yarn 10, possibly after a short interruption, is now back-fed from bobbin 51. The negative pressure prevailing inside suction pipe 6 takes its full effect at the outlet side 311 of the torsion element 3, where the yarn end is located. The yarn 10 is thus sucked through the torsion element and into the suction pipe 6.
When the back-fed yarn end has extended sufficiently far into the suction pipe 6, yarn back-feeding is stopped and the torsion element 3 is moved back into its spinning position I, whereby the gap 34 is uncovered again by the sealing device 61.
Through coordinated release of the roving 1 by the clamping devices 202 and 212 for the roving, through the resumption of air feeding through the compressed air openings 300, 310 into the interior of the torsion element 3 and through the beginning of winding and yarn draw-off (which may be delayed somewhat in relation to winding), the yarn 10 is combined with the roving 1 and the normal spinning process is thus resumed.
Through the reopening of the gap 33 between the injector nozzle 30 and the torsion nozzle 31 as well as of the gap 34 in the holding device 32 when draw-off of the spun yarn 10 by bobbin 51 begins, and possibly also by the draw-off device 4, the air required for the spinning process can be sucked through the gap 33/34 into the interior of the torsion element 3.
The sealing device 61 shown in FIGS. 1 and 2 is provided with a screen 610 which is fixedly supported and to which the torsion element 3 is associated through its movement from spinning position I into threading position II. The details of a particularly advantageous example of an embodiment of the invention are now explained through FIG. 2. The holding device 32 is here supported on a swivelling lever 35, capable of being swivelled around a bearing bolt 350.
A first stop 36 is associated to the torsion element 3. The swivelling lever 35 is subjected to the pull of a tension spring 351, one end of which is attached to the swivelling lever 35 and the other end of which is attached to the stop 36. The torsion element 3 is thus normally held by tension spring 351 in contact with the stop 36 which is designed so that the torsion element 3 which touches it assumes spinning position I. In this position, the gap 34 is not covered by the stop 36.
The swivelling lever 35 is connected via a coupling 370 to the anchor 371 of a solenoid 37. When the solenoid 37 is excited, the torsion element 3 is brought, in opposition to the force exerted by tension spring 351, from the spinning position I into the threading position II, thus being applied against the screen 610 which is formed as a stop, so that the gap 33/34 is sealed against the atmosphere in this position. When the back-fed yarn 10 has been threaded into the torsion element 3, said torsion element 3 is released again as the excitation of solenoid 37 stops and returns into its spinning position I in which it is once more in contact with the stop 36.
The invention is not limited to the embodiments described, but can be varied in many ways, in particular through the replacement of features by equivalents or through different combinations thereof. Such a variant of the sealing device 61 is explained below through FIG. 3. In this embodiment, too, the gap 33/34 is sealed by being covered. The torsion element 3 is, as shown in FIG. 2, pulled by a tension spring 351 which is fixedly attached at a suitable location. The swivelling lever 35 is equipped with a second arm 352 which is held in contact with the stationary stop 38 determining the spinning position I of the torsion element 3, under the effect of the tension spring 351.
The sealing device 61 which can be associated to the gap 34 of the torsion element 3 is provided with a screen 611 which constitutes at the same time a driving device for the torsion element 3. The screen 611 is supported jointly with the swivelling lever 35 on the bearing bolt 350 so that when the torsion element 3 is swivelled, the swivelling of screen 611 prevents any relative movement from occurring between the torsion element 3 and the screen 611.
In normal spinning operation the torsion element 3 is in its spinning position I. The screen 611 is then in its left position (indicated by alternating dots and dashes in FIG. 3), in which it lays open gap 34. For piecing after yarn breakage (or immediately upon the occurrence of a yarn breakage) the solenoid 37 (FIG. 2) is excited and thus moves the screen 611 toward the torsion element 3. By being applied against the torsion element 3, the screen 611 covers the gap 34. As the swivelling movement is continued, the screen 611 serves as a driving device for the torsion element 3 and transfers it from its spinning position I into its threading position II (indicated by dashed lines in FIG. 3).
In such an embodiment of the sealing device 61, the gap 34 in the holding device 32, and thereby also the gap 33 between the injector nozzle 30 and the torsion element 31, is covered during the threading phase.
The threading position II of the torsion element 3 can be determined by appropriately sizing the stroke of the solenoid 37. However, it is also possible to associate additionally a stop 62 to the swivelling lever 35, determining the threading position II of the torsion element 3 (FIG. 3).
If desired, the swivelling movement of the screen 611 can also serve to control the stream of compressed air in the torsion element 3. The screen 611 can for example open or close the lines 322 and 323 in function of its position in relation to the torsion element 3. In the left end-position (indicated by alternating dots and dashes in FIG. 3), in which the screen 611 is lifted away from the torsion element 3, said screen 611 lays open the lines 322 and 323, so that the torsion element 3 is subjected to overpressure. When a yarn breakage occurs, the screen 611 is applied against the torsion element 3 and thus also interrupts the arrival of compressed air to said torsion element 3. The flow of compressed air to the torsion element 3 also remains suspended after threading of the yarn 10 into the torsion element 3, even if the latter has returned to its spinning position I. In synchronization with the release of the roving and with the resumption of yarn withdrawal by bobbin 51 and/or draw-off device 4, the flow of air to the torsion element 3 is also resumed through the return of the screen 611 into its starting position, indicated by alternating dots and dashes in the drawing.
FIGS. 4 and 5 represent an embodiment of the threading device 6 in which the injector nozzle 30 and the torsion nozzle 31 can be moved in relation to each other along their axis in such a manner that they are axially pressed against each other during the threading phase. In this embodiment, the torsion nozzle 31 is fixedly supported in the holding device 32, while the injector nozzle 30 can be moved in axial direction. For this purpose the injector nozzle 30 and the torsion nozzle 31 are provided with ring-shaped recesses 303 and 313 respectively around their spinning bores 302 and 312, on their sides facing each other, for the seating of a compression spring 324. Furthermore, a stop bolt 325 is supported in the holding device 32, said stop bolt 325 extending radially inward up to an oblong slit 304 on the outside of the injector nozzle 30. This oblong slit 304 limits the maximum extension of the compression spring 324 in one direction, and thus the movement of the injector nozzle away from the torsion nozzle 31, while it is of such length in the other direction as to allow complete contact between the ends of the injector nozzle 30 and the torsion nozzle 31 facing each other.
In the embodiment shown, on either side of the ring channel 320, the seal rings 326 and 327 are provided between the holding device 32 and the injector nozzle 30. In addition, the injector nozzle 30 is also equipped with a seal ring 328 on its side toward the suction pipe 6, said seal ring 328 interacting with the opening 600 of the suction pipe 60. An additional seal can be provided in one or both ends facing each other of the injector nozzle 30 and the torsion element 31.
When the torsion element 3 has been brought into its threading position II for the threading of the back-fed yarn 10, the suction pipe 60 is brought into its yarn receiving position in front of the end constituting the inlet 301 of the torsion element 3 during the normal spinning process, whereby it comes into sealing contact with the injector nozzle 30. The suction pipe 60 however continues its movement in direction of the injector nozzle 30, until the injector nozzle 30 is applied against the torsion nozzle 31, thus closing the gap 33 between them, while the compression spring 324 is tensed.
The yarn end is now sucked back through the torsion element 3 and into the suction pipe 60 in the manner described above, whereby the yarn 10 is released for this back-feeding to the suction pipe 60 through reverse rotation of the bobbin 51 or through the release of a previously constituted yarn reserve. Since extraneous air streams between the outlet side 311 of the torsion element 3, to which the back-fed yarn is presented, and the suction pipe 60 are eliminated, the full negative pressure prevailing within the suction pipe 60 acts also at the outlet side 311 of the torsion element 30, and this creates the necessary condition so that threading of the yarn 10 into the torsion element 3 to be effected with relatively weak negative pressure.
Another embodiment of the sealing device 61 is shown in FIG. 6. In this embodiment the holding device 32 of the torsion element 3 is equipped with a sleev-like screen 612 which surrounds said holding device 32 in the axial zone of the injector nozzle 30. The holding device 32 is provided with a ring shoulder 340 extending radially outward, in its zone facing gap 34 in the axial zone of the injector nozzle 30, while the screen 612, on its end facing the outlet side 301, is provided with a ring shoulder 613 extending radially inward and reaching up to the outer circumference of the holding device, while its inner circumference is otherwise equal to the outer circumference of the ring shoulder 340. A compression spring 614 is installed in the space thus formed between the ring shoulders 340 and 613.
The screen 612 is equipped, at its end facing the torsion nozzle 31, with an outer thread 615 on which is screwed a cap 616 which, under the pressure exerted upon it by the compression spring 614 via screen 612, is applied to the side of the ring shoulder 340 which faces the torsion nozzle 31 and which thus acts as a stop.
In its zone facing the gap 34, in the axial zone of the torsion nozzle 31, the holding device 32 is provided with a ring shoulder 341 with a ring-shaped recess 342 which receives a ring seal 342.
The force of the compression spring 614 holds the screen 612 and its cap 616 pressed against the ring shoulder 340 of the holder 32. When the torsion element 3 has been brought into its threading position II, the suction pipe 60 is associated to its outlet side 301 (see FIG. 2). This suction pipe 60 is then pressed against the screen 612 with such force that said screen 612 is applied against the ring seal 342, in opposition to the effect of the compression spring 614, thus sealing the gap 34 in the holding device 32.
Even if the closing of the gaps 33 or 34 has always been effected by the suction pipe 60 in the examples of embodiments described above through FIGS. 4 to 6, this is not necessarily the case in every instance. It is equally possible to bring about such an axial shifting of the torsion nozzle 31 or of a sleeve-like screen surrounding the torsion nozzle 31 (similar to 612) in the direction of the injector nozzle, whereby the drive can be constituted for example by a suction device (not shown) which accepts the yarn 10 from the bobbin 51, or by another component of the element constituting the yarn feed-back device. Opposite movements of the injector nozzle 30 and of the torsion nozzle 31, or of sleeves which surround these two nozzles 30 and 31 are also possible.
Neither is it necessary for the torsion element 3 to be supported on a swivelling lever 35, but it can be swivelled by means of a swivelling axle (not shown) on the torsion element 3 itself in such a manner that at least its inlet side 301 assumes a threading position II which is different from the spinning position I. Shifting of the torsion element 3 in a slide-like guide (not shown) can be provided, if desired. The kind of transfer from spinning position I to threading position II is therefore immaterial for the instant invention. | In a spinning device of the type equipped with a torsion element having an injector nozzle and a torsion nozzle which are separated from each other during spinning by a gap which is open to the atmosphere, yarn is threaded for piecing into such torsion element, which is brought into a threading position. Threading is effected with the assistance of negative pressure which is applied to the torsion element from the side thereof which constitutes its inlet side during normal spinning. The gap between the injector and torsion nozzles is sealed against the atmosphere before threading of the yarn. Thereafter, and at the latest at the beginning of the withdrawal of the pieced yarn, the gap is opened once more. A sealing device, which may assume various alternative constructions, is provided to carry out the process by sealing the gap between the injector nozzle and the torsion nozzle during the threading phase. | 3 |
TECHNICAL FIELD
The present invention relates generally to an engine cooling systems and more specifically to a coolant motor fan drive.
BACKGROUND ART
Generally, a water-cooling type engine of a vehicle includes a cooling system provided with a radiator and a flow control valve. The radiator is located in an engine coolant circuit for cooling the coolant. The flow control valve regulates the flow of the coolant that passes through the radiator. The flow control valve is controlled to change the coolant flow in the radiator (hereafter, “the radiator flow”). This adjusts the temperature of the coolant, which cools the engine.
The flow control valve is fully closed to minimize the radiator flow when the coolant temperature is relatively low. In contrast, when the coolant temperature is relatively high, the flow control valve is fully opened to maximize the radiator flow. Otherwise, a feedback control procedure is performed to vary the opening size of the flow control valve (the radiator flow) depending on the coolant temperature, such that the coolant temperature seeks a predetermined target.
To cool the coolant within the radiator, a cooling fan is mounted in close proximity to the radiator to providing cooling airflow to the radiator. Preferably, the cooling fan is coupled to the water pump.
However, many engine-cooling applications do not allow for conventional mounting of an engine-cooling fan on a water pump. For example, front wheel drive systems, or systems where the centerline of the water pump is not covered by the radiator, use electric motor driven systems or hydraulically driven fans to control the temperature of the coolant leaving the radiator. These systems are costly and inefficient.
Another potential issue related to cooling system performance is electrical power usage. As automotive manufacturers continue to introduce optional electrical equipment on automobiles, electrical demands within the vehicle correspondingly are increased. Further, customer demands for increased horsepower and towing capacity create additional demands on electrical systems. These extra demands place increased burdens on cooling systems to cool the engine compartment without significantly increasing electrical demand.
It is thus highly desirable to provide a way to cool an engine using an existing source of power that is economical and efficient.
SUMMARY OF THE INVENTION
The present invention utilizes an existing source of power, the coolant flow, and an economical water motor to drive an engine-cooling fan mounted to a water pump.
The control of the coolant flow is accomplished through valving or by adjusting the impeller rotational speed of the water pump, or a combination of both. Since the duty cycle of the cooling system is low, a clutch or recirculation path can be used when coolant flow or airflow requirements are low, thereby saving energy and providing an alternative control method.
During normal operation, where engine cooling is not required, the speed control coupling maintains a slow and constant water pump speed at all engine-operating speeds. The valve is maintained in a closed position and stops coolant flow from entering the radiator. Coolant is directed instead through a heater to maintain circulation and control hot spots and allow rapid engine warm-up.
If engine cooling is required, the valve is actuated and coolant is circulated to the engine and through the radiator and water motor at low pump speeds. The water motor and coupled fan are then actuated, thereby cooling the coolant as it flows through the radiator. If cooling requirements increase, the water pump is switched to high speed and the system operates at maximum heat rejection capacity.
When airflow for the air conditioner condenser is needed, the speed control coupling simply increases the water pump speed, and hence the fan speed. This can be controlled from air conditioner head pressure or simply actuated with the air conditioner compressor. Pilot pressure at the valve can direct coolant flow back to the pump by passing the engine and avoiding overcooling.
If both cooling and air conditioning are required, the pump speed coupling and the valve are both actuated to drive the fan at maximum speed and pump all the coolant through the engine.
In alternative preferred embodiments, because of the huge rpm range of some motors, a dual stage pump is used as either the water pump, water motor, or both the water pump and water motor. The dual stage pump allows for a more varying response between engine speed and pump/fan output.
Other objects and advantages of the present invention will become apparent upon the following detailed description and appended claims, and upon reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an engine cooling system according to a preferred embodiment of the present invention having a valve in a closed position;
FIG. 2 is a perspective view of FIG. 1 in which the valve is in an open position;
FIG. 3 is a perspective view of FIG. 1 in which the valve is in a third position;
FIG. 4 is a perspective view of an engine cooling system according to another preferred embodiment of the present invention;
FIG. 5 is a perspective view of an engine cooling system according to another preferred embodiment of the present invention; and
FIG. 6 is a perspective view of an engine cooling system according to another preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1-3 , a perspective view of a cooling system used to cool an engine 22 of a vehicle 10 in one preferred embodiment is generally designated as 20 . The engine 22 has a crankshaft 24 coupled to a crankshaft pulley 26 . The crankshaft pulley 26 is rotatably coupled to a water pump 28 via a pump control coupling 30 , which is coupled to the crankshaft pulley 26 via a belt 32 . The cooling system 20 also has a heater element 47 used to increase the temperature of the engine 22 as desired and to provide heated air to the passenger cabin of the vehicle as desired by a vehicle user 75 . The cooling system 20 also has an air-conditioning unit 69 providing cooling airflow to the passenger cabin as requested by the user 75 .
The location of the user 75 relative to the heater element 47 and air conditioner 69 , as shown in FIGS. 1-6 of the present invention, is merely for illustrative purpose only, and is not representative of their actual positioning within the vehicle 10 .
The cooling system has a series of coolant lines 36 , 44 , 48 used to fluidically couple the various components of the cooling system 20 to maintain the engine 22 at an optimal operating temperature at a given engine speed while maintaining the passenger cabin at a desired temperature for the user 75 .
The water pump 28 is fluidically coupled to a heater element 47 and to the engine 22 through a first coolant line 44 . A second coolant line 36 is fluidically coupled to the first coolant line 44 at a first end, terminating at a first junction 51 . The second coolant line is also fluidically coupled at its opposite end to the first coolant line 44 , terminating at a second junction 52 .
A water motor 38 having an attached fan 40 is fluidically coupled with the second coolant line 36 between radiator 34 and water pump 28 . The fan 40 is coupled in such a way as to provide cooling airflow to the radiator 34 when rotating. A valve 60 coupled to the second coolant line 36 is located between the radiator 34 and second junction 52 .
A third coolant line 48 is fluidically coupled to the second coolant line 36 through the valve 60 at one end and to the first coolant line 44 at junction 50 at a second end such that the third coolant line bypasses the engine 22 .
Thus, the coolant lines 36 , 44 , 48 form a continuous closed loop and contain a quantity of coolant 80 there within that is used to warm up or cool down the engine 22 to maintain the engine 22 is a desired temperature operating zone.
The pump control coupling 30 , also known as a speed control coupling 30 , preferably takes the form of an on/off electric clutch or an electrically controlled viscous clutch well known to those of ordinary skill in the art. As such, the amount of rotational response of the coupled water pump 28 is controlled as a function of the degree of engagement of the pump control coupling 30 .
The cooling system also has an air conditioner 69 including a condenser 71 and a compressor 73 . The air conditioner 69 is controlled by a user 75 and is also electrically coupled to the controller 70 . The condenser 71 is capable of receiving cooling airflow (ram flow) from outside air as the vehicle is moving.
The valve 60 , heater element 47 , air conditioner 69 , and pump control coupling 30 are all electrically coupled to and controlled by a controller 70 . In addition, at least one temperature sensor 77 is coupled to the controller 70 and measures the temperature of the engine 22 during operating conditions.
While one temperature sensor 77 is shown as being coupled to the engine 22 in FIGS. 1-3 , the number and location of the temperature sensor 77 could vary greatly within cooling systems 20 and still accurately measure the engine operating temperature. For example, the temperature sensor 77 could be alternatively mounted to cooling line 44 between the engine 22 and junction 50 . Further, multiple temperature sensors 77 located throughout the cooling system could all be coupled to the controller and used to accurately measure engine operating temperature. Thus, the number and location of temperature sensors 77 is not meant to be limited to that illustrated in FIGS. 1-3 .
In warm-up conditions, as displayed in FIG. 1 , wherein the engine 22 is operating below a desired operating temperature (as measured by the temperature sensor 77 ), the controller 70 will direct the valve 60 closed and the speed control coupling 30 to maintain a slow and constant water pump 28 speed. Thus coolant 80 will thus flow from the water pump 28 , through first coolant line 44 and the heater element 47 and the engine 22 , therein returning to the pump 28 . This coolant 80 is warmed as is flow through the jeater element 47 to allow for rapid engine 22 warm-ups. However, because the coolant 80 is constantly flowing through the first coolant line 44 , hot spots are eliminated on the engine 22 . The controller 70 can also control the amount of heat exchanged to the coolant 80 within the heater element 47 by simply increasing or decreasing the temperature of the heater element 47 itself, or by slightly altering the rotational speed of the speed control coupling 30 (and water pump 28 ), or by a combination of pumping speed control and heater control.
As engine operating temperatures increase closer to, but still below, a desired engine operating temperature, the controller 70 will direct the speed coupling 30 to increase its rotational speed, therein increasing the rotational rate of the water pump 28 in response, which in turn increases the flow rate of coolant 80 as it flows through the water pump 28 and heater element 47 . Thus, coolant 80 flows through the heater element 47 at a higher flow rate, which translates into less heat transfer per unit coolant 80 . Thus, the engine 22 will continue to warm-up, but at a lesser relative rate.
At the desired engine operating temperature, as shown in FIG. 2 , the controller 70 will direct the valve 60 to open, therein allowing coolant 80 to flow through the second coolant line 36 from the first junction 51 to the second junction 52 . This coolant flow engages water motor 38 to drive fan 40 , which provides cooling airflow to the radiator 34 . Thus, as coolant 80 flows through the radiator 34 , the coolant 80 is cooled in proportion to the coolant flow rate through the radiator and in proportion to the fan 40 rotational rate, which provides cooling air flow to the radiator 34 as the fan 40 is rotated by the water motor 38 .
At the same time, coolant 80 flows from pump 28 and through the first coolant line 44 . The cooler coolant 80 from second coolant line 36 merges with the warmer coolant 80 from the first coolant line 44 at junction 52 and continues to flows through the engine 22 . Thus, the cooler coolant 80 flowing through the second coolant line 36 and the warmer coolant 80 flowing through the first coolant line 44 merge at junction 52 and flow together back through the engine 22 and line 44 to pump 28 .
If engine temperatures increase over a desired engine operating temperature, the controller 70 simply directs the speed controller 30 to increase the water pump 28 speed, while maintaining the valve 60 in an actuated or open position. This in turn increases the water motor 38 speed, and hence the fan 40 rotational speed. The net effect is that more cooling airflow is directed to the radiator 34 from the fan 40 , which decreases the coolant 80 temperature further. At the same time, coolant 80 flowing through line 44 and heater element 47 is not warmed as much as at slower pump speeds. Thus, as the pump speed 28 increases, merged coolant 80 flowing from junction 52 to engine 22 is cooler than at lower pump speeds, which in turn aids in cooling the engine 22 as the merged coolant 80 returns to the water pump 28 through coolant line 44 .
When the user 75 desires air conditioning to cool the cabin area of the vehicle, the user 75 simply turns on the air conditioning 69 within the cabin of the vehicle. In order to accommodate this request, as shown in FIG. 3 , cooling airflow for the air conditioning condenser 71 is needed to condense freon contained within the condenser 71 from a gas to a liquid. Pilot pressure generated within the compressor 73 as the air conditioner 69 is activated actuates the valve 60 to move from either a closed position or an open position to a second open position such that coolant may flow from line 36 through line 48 and back to the water pump 28 . At the same time, coolant 80 flow from the second coolant line 36 between the valve 60 and junction 52 and to the engine 22 is prevented. Thus, coolant 80 flows through water motor 38 , therein activating the fan 40 to provide additional cooling airflow to the radiator 34 and condenser 71 . The coolant 80 exits the radiator 34 and returns to the water pump 28 through valve 60 , third coolant line 48 , junction 50 , and first coolant line 44 .
If additional cooling is desired, especially at idle conditions, the controller 70 will direct the speed coupling 30 to increase its rotational speed at a given engine speed, and hence the water pump 28 speed, which in turn increases the pumping speed of water motor 38 and rotational speed of the fan 40 . This further increases airflow from the fan 40 to the air conditioner condenser 71 .
If both engine cooling, as sensed by sensor 77 , and air conditioning 69 is requested by the user 75 , the controller 70 actuates the pump speed coupling 30 to produce maximum pumping action and directs the valve 60 from the second open position (or closed position, depending upon the pilot pressure within the compressor 73 ) to the first open position to provide coolant 80 flow back from the radiator 34 to the engine 22 through second line 36 to junction 52 . This drives the fan 40 at maximum speed while allowing coolant 80 to pass through the line 36 and the junction 52 to the engine 22 .
FIGS. 4-6 illustrate three more preferred embodiments of the present invention that are essentially useful for vehicle cooling systems in which the engines that they cool have a high range of potential engine speeds, especially as compared with idling conditions. For example, in FIG. 4 , a dual stage water pump 128 is utilized in place of the single stage water pump 28 of FIGS. 1-3 . In FIG. 5 , a dual stage water motor 138 replaces the single stage water motor 38 of FIGS. 1-3 . FIG. 6 incorporates a dual stage water pump 128 and a dual stage water motor 138 .
A dual stage water pump 128 , as shown in FIGS. 4 and 6 , consists of a pair of independently actuated pumps 129 , 130 (i.e. stages) coupled to the speed control coupling 30 . Each pump 129 , 130 is electrically coupled to the controller 70 . Depending upon the desired coolant flow rate, one or both pumps may be actuated. When both pumps 129 , 130 are actuated, the coolant flow rate increases as compared with the use of a single one of the two pumps. As such, the coolant flow rate can be adjusted stepwise in conjunction with the speed control coupling 30 .
A dual stage water motor 138 , as shown in FIGS. 5 and 6 , consists of a pair of independently actuated water motors 139 , 140 (i.e. stages) coupled to the speed control coupling 30 . Each pump 139 , 140 is electrically coupled to the controller 70 . Depending upon the desired coolant 80 flow rate and fan 40 rotation rate, one or both pumps may be actuated. When both pumps 139 , 140 are actuated, the coolant flow rate and fan 40 rotational rate increases as compared with the use of a single one of the two pumps. As such, the temperature and coolant flow rate of coolant flowing through the second line 36 can be adjusted stepwise in conjunction with the speed control coupling 30 . This allows for more precise control of temperature of the coolant entering the engine when the valve 60 is in an open position. This can lead to improved fuel economy and emissions.
The dual stage nature of the water pump and water motor allows both stages to be working in conditions where maximum coolant flow is required, such as in engine idle conditions in which the engine is above the desired operating temperature. However, when the vehicle is moving, or when the vehicle is below the desired operating temperature, one of the stages may be turned off.
In addition, the dual stage nature is especially useful in engines having a high variation of engine speeds. Thus, for example, when low engine speeds are present, such as in engine idle, the water pump 128 can be directed to only utilize a single stage. As engine speeds increase, for example to 5000-6000 revolutions per minute (rpms), the second stage 130 may be activated. Thus, less horsepower is required to drive the speed coupling 30 , and excess horsepower can be utilized elsewhere in the engine, therein increasing engine performance in terms of available horsepower, emissions, and fuel economy. Additionally, less electrical energy is needed to control the speed coupling 30 .
With respect to FIG. 4 , in warm-up conditions, wherein the engine 22 is operating below a desired operating temperature as measured by a temperature sensor 77 , the controller 70 will direct the valve 60 closed and the speed control coupling 30 to maintain a slow and constant water pump 128 speed. In warm-up conditions, only one stage of the dual stage water pump 128 is on, therein limiting the coolant flow rate through line 44 and the heater element 47 to provide maximum warming of the coolant 80 within the heater element 47 .
As engine operating temperatures increase closer to, but still below, a desired engine operating temperature, the controller 70 will direct the speed coupling 30 to increase its rotational speed, therein increasing the flow rate of coolant 80 through the water pump 128 and heater element 47 . Alternatively, or in conjunction with increasing the rotational speed of the speed coupling 30 , the controller 70 will turn on the second stage of the water pump, therein increasing the coolant 80 flow.
At the desired engine operating temperature, the controller 70 will direct the valve 60 to open, therein allowing coolant 80 to flow through second line 36 from the first junction 51 to the second junction 52 . This engages water motor 38 to drive fan 40 , which provides cooling airflow to the radiator 34 . Thus, as coolant 80 flows through the radiator, the coolant is cooled. At the same time, coolant 80 flows from pump 128 and through first coolant line 44 . The cooler coolant 80 from the second coolant line 36 merges with the warmer coolant 80 from the first coolant line 44 at junction 52 . The merged coolant continues to flow through the first coolant line, 44 and back to the pump 128 .
At the desired engine operating temperature, as the vehicle 10 is moving, one or both stages of the dual stage water pump 128 is on, therein controlling the coolant flow rate through both lines 36 , 44 . However, during engine idle conditions, only one stage of the dual stage water pump 128 is typically activated, therein decreasing the flow rate of coolant 80 through both lines 36 , 44 to maintain the engine in a desired operating zone.
If engine temperatures increase over a desired engine operating temperature, the controller 70 simply directs the speed controller 30 to increase the water pump 128 speed while maintaining the valve 60 in an actuated position. Alternatively, or in conjunction with this speed increase, the controller 70 may actuate both stages of the water pump 128 . This in turn increases the water motor 38 speed, and hence the fan 40 rotational speed. The net effect is that more cooling airflow is directed to the radiator 34 from the fan 40 , which decreases the coolant 80 temperature further. Thus, as the pump speed 128 increases, coolant flowing from junction 52 is cooler than at lower pump speeds, which in turn aids in cooling the engine 22 as the coolant 80 returns to the water pump 128 through coolant line 44 .
When the user 75 desires air conditioning to cool the cabin area of the vehicle 10 , he simply turns on the air conditioning 69 within the cabin of the vehicle 10 . As described above, the increase in pilot pressure actuates the valve 60 to allow coolant 80 flowing through the second coolant line 36 to bypass the engine 22 through junction 52 and flow instead through line 48 and back to the pump 128 . The controller 70 simply directs the speed controller 30 to increase the water pump 128 speed, and hence the coolant flow, through the second coolant line 36 and third coolant line 48 . Alternatively, or in conjunction with this speed increase, the controller 70 actuates one or both stages of the dual action pump.
If additional cooling is desired, especially at idle conditions, the controller 70 will direct the speed coupling 30 to increase its rotational speed and actuate dual stages, and hence the water pump 28 speed, which in turn increases the water motor 38 and fan speed 40 . This further increases airflow from the fan 40 to the air conditioner condenser 71 .
If both engine cooling, as sensed by sensor 77 , and air conditioning is requested, the controller 70 actuates the pump speed coupling 30 to produce maximum pumping action, utilizing both stages of the dual stage pump 128 , and opens valve 60 to provide coolant flow back from the radiator 34 to the engine 22 through coolant line 36 and junction 52 . This drives the fan 40 at maximum speed while allowing the cooled portion of the coolant 80 to pass through the engine 22 .
With respect to FIG. 5 , in warm-up conditions, wherein the engine 22 is operating below a desired operating temperature as measured by a temperature sensor 77 , the controller 70 will direct the valve 60 closed and the speed control coupling 30 to maintain a slow and constant water pump 28 speed, therein limiting the coolant flow rate through line 44 and the heater element 47 to provide maximum warming of the coolant 80 within the heater element 47 .
As engine operating temperatures increase closer to, but still below, a desired engine operating temperature, the controller 70 will direct the speed coupling 30 , and hence the water pump 28 rotational speed, therein increasing the flow rate of coolant 80 through the water pump 28 and heater element 47 .
At the desired engine operating temperature, the controller 70 will direct the valve 60 to open, therein allowing coolant 80 to flow through second line 36 from the first junction 51 to the second junction 52 . This engages the dual stage water motor 138 to drive fan 40 , which provides cooling airflow to the radiator 34 . Thus, as coolant 80 flows through the radiator 34 , the coolant 80 is cooled. At the same time, coolant 80 flows from pump 28 and through first coolant line 44 . The cooler coolant 80 from the second coolant line 36 merges with the warmer coolant 80 from the first coolant line 44 at junction 52 . The merged coolant continues to flow through the first coolant line 44 and back to the pump 28 .
To precisely control the amount of cooling of the coolant occurring in the radiator, the controller may direct on one or both stages 139 , 140 of the water motor. The rotational rate of the fan 40 is greater, and hence the amount of airflow to the radiator 34 , at a given pump 28 speed, when both stages 139 , 140 are actuated. The incorporation of a dual stage water motor 138 allows different cooling characteristics to be achieved for coolant 80 returning to the engine 22 through junction 52 , hence the merged coolant will be cooler if both stages 139 , 140 are actuated and slightly warmer if only one stage 139 is used.
If engine temperatures increase over a desired engine operating temperature, the controller 70 simply directs the speed controller 30 to increase the water pump 28 speed while maintaining the valve 60 in an actuated position. Alternatively, or in conjunction with this speed increase, the controller 70 may actuate both stages 139 , 140 of the water pump 128 . This in turn increases the water motor 38 speed, and hence the fan 40 rotational speed, as compared with one stage 139 being actuated. The net effect is that more cooling airflow is directed to the radiator 34 from the fan 40 , which decreases the coolant 80 temperature further. Thus, as the pump speed 28 increases, coolant flowing from junction 52 is cooler than at lower pump speeds, which in turn aids in cooling the engine 22 as the coolant 80 returns to the water pump 128 through coolant line 44 .
When the user 75 desires air conditioning to cool the cabin area of the vehicle 10 , he simply turns on the air conditioning 69 within the cabin of the vehicle 10 . As described above, the increase in pilot pressure actuates the valve 60 to allow coolant 80 flowing through the second coolant line 36 to bypass the engine 22 through junction 52 and flow instead through line 48 and back to the pump 128 . The controller 70 simply directs the speed controller 30 to increase the water pump 28 speed, and hence the coolant flow, through the second coolant line 36 and third coolant line 48 .
If both engine cooling, as sensed by sensor 77 , and air conditioning 69 is requested, the controller 70 actuates the pump speed coupling 30 to produce maximum pumping action by the pump 28 , and opens valve 60 to provide coolant flow back from the radiator 34 to the engine 22 through coolant line 36 and junction 52 . The controller 70 will also direct one or both stages 139 , 140 of the water motor 138 to drive the drives the fan 40 at the desired rotational speed while allowing the cooled portion of the coolant 80 to pass through the engine 22 , and not bypass the engine 22 through line 48 .
With respect to FIG. 6 , in warm-up conditions, wherein the engine 22 is operating below a desired operating temperature as measured by a temperature sensor 77 , the controller 70 will direct the valve 60 closed and the speed control coupling 30 to maintain a slow and constant water pump 128 speed. In warm-up conditions, only one stage of the dual stage water pump 128 is on, therein limiting the coolant flow rate through line 44 and the heater element 47 to provide maximum warming of the coolant 80 within the heater element 47 .
As engine operating temperatures increase closer to, but still below, a desired engine operating temperature, the controller 70 will direct the speed coupling 30 to increase its rotational speed, therein increasing the flow rate of coolant 80 through the water pump 128 and heater element 47 . Alternatively, or in conjunction with increasing the rotational speed of the speed coupling 30 , the controller 70 will turn on the second stage 130 of the water pump 128 , therein increasing the coolant 80 flow.
At the desired engine operating temperature, the controller 70 will direct the valve 60 to open, therein allowing coolant 80 to flow through second line 36 from the first junction 51 to the second junction 52 . This engages water motor 138 to drive fan 40 , which provides cooling airflow to the radiator 34 . Thus, as coolant 80 flows through the radiator, the coolant 80 is cooled. At the same time, coolant 80 flows from pump 128 and through first coolant line 44 . The cooler coolant 80 from the second coolant line 36 merges with the warmer coolant 80 from the first coolant line 44 at junction 52 . The merged coolant continues to flow through the first coolant line 44 and back to the pump 128 . Depending upon the characteristics of the engine 22 , one or both stages 139 , 140 of the water motor 138 may be actuated by the controller 70 .
At the desired engine operating temperature, as the vehicle 10 is moving, one or both stages of the dual stage water pump 128 is on, therein controlling the coolant flow rate through both lines 36 , 44 . However, during engine idle conditions, only one stage of the dual stage water pump 128 is typically activated, therein decreasing the flow rate of coolant 80 through both lines 36 , 44 to maintain the engine in a desired operating zone. Also, one or both stages 139 , 140 of the water motor are activated to further regulate the temperature of the coolant 80 flowing through line 36 and back to the engine 22 .
If engine temperatures increase over a desired engine operating temperature, the controller 70 simply directs the speed controller 30 to increase the water pump 128 speed while maintaining the valve 60 in an actuated position. Alternatively, or in conjunction with this speed increase, the controller 70 may actuate both stages 129 , 130 of the water pump 128 . This in turn increases the water motor 138 speed, and hence the fan 40 rotational speed. The net effect is that more cooling airflow is directed to the radiator 34 from the fan 40 , which decreases the coolant 80 temperature further. Thus, as the pump speed 128 increases, coolant 80 flowing from junction 52 is cooler than at lower pump speeds, which in turn aids in cooling the engine 22 as the coolant 80 returns to the water pump 128 through coolant line 44 . Typically, both stages 139 , 140 of the dual stage water motor 138 will be actuated by the controller 70 to provide maximum fan 40 rotational speed to cool the coolant 80 as it flows through the radiator 34 .
When the user 75 desires air conditioning to cool the cabin area of the vehicle 10 , he simply turns on the air conditioning 69 within the cabin of the vehicle 10 . As described above, the increase in pilot pressure actuates the valve 60 to allow coolant 80 flowing through the second coolant line 36 to bypass the engine 22 through junction 52 and flow instead through line 48 and back to the pump 128 . The controller 70 simply directs the speed controller 30 to increase the water pump 128 speed, and hence the coolant flow, through the second coolant line 36 and third coolant line 48 . Alternatively, or in conjunction with this speed increase, the controller 70 actuates one or both stages 129 , 130 of the dual action pump 128 and/or one or both stages 139 , 140 of the water motor 138 .
If additional cooling is desired, especially at idle conditions, the controller 70 will direct the speed coupling 30 to increase its rotational speed and actuate dual stages 129 , 130 of the water pump 128 , and hence the water pump 128 speed, which in turn increases the water motor 138 and fan speed 40 . This further increases airflow from the fan 40 to the air conditioner condenser 71 . Also, typical both stages 139 , 140 of the water motor are activated to further decrease the temperature of the coolant 80 flowing through line 36 and back to the engine 22 .
If both engine cooling, as sensed by sensor 77 , and air conditioning 69 are requested, the controller 70 actuates the pump speed coupling 30 to produce maximum pumping action, utilizing both stages 129 , 130 of the dual stage pump 128 , and open valve 60 to provide coolant flow back from the radiator 34 to the engine 22 through coolant line 36 and junction 52 . Also, typically both stages 139 , 140 of the water motor are activated to provide maximum fan 40 rotational speed to further decrease the temperature of the coolant 80 flowing through line 36 and back to the engine 22 .
While one particular embodiment of the invention have been shown and described, numerous variations and alternative embodiments will occur to those skilled in the art. Accordingly, it is intended that the invention be limited only in terms of the appended claims. | The control of the coolant flow is accomplished through valving or by adjusting the pumping speed of a water pump and a water motor, or a combination of all three elements. During normal operation, where engine cooling is not required, the speed control coupling maintains a slow and constant water pump speed at all engine-operating speeds. The valve is maintained to stop coolant flow from entering the radiator while allowing coolant to flow through a heater. If engine cooling is required, the valve is actuated such that coolant is circulated to the engine and through the radiator. If air conditioning is required, the speed control coupling simply increases the water pump speed and the fan speed while the valve is set to bypass coolant flow to the engine. If air conditioning and engine cooling are required, the valve is actuated to allow coolant flow to the engine. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an image forming apparatus that can form two images on one round of an intermediate transfer material.
[0003] 2. Related Background Art
[0004] Color copying machines and color printers which output color documents in offices were not the existence of being used easily because of expensive main part cost and running cost at the beginning in comparison with monochrome machines although there were potential demands. This is because most business documents were monochrome outputs and there were few color copying machines and color printers with low costs and low running costs which balance to few color outputs. However, color copying machines and color printers achieving main part costs and running costs almost equivalent to monochrome machines as office applications and enabling color outputs easily in offices have been developed in recent years. Hence, replacement to the color machines has been progressing in offices instead of conventional monochrome machines.
[0005] In order to replace a monochrome machine with a color machine in this manner, a space of its main part also becomes important as well as the realization of functions being the same as those of a monochrome machine. For this reason, in comparison with a tandem type color image forming apparatus formed by horizontally arranging four photoconductive (or photosensitive) drums which form four colors of images for color image formation concurrently, one-drum type image forming apparatus, which uses one photoconductive drum and transfers an image, formed on the photoconductive drum, on an intermediate transfer material, and forms four colors of images by four revolutions of a developer by switching the developer to another every round of the intermediate transfer material, not only can depress the size of the apparatus itself, but also can keep main part cost low. In addition, in the case of printing both sides, although it is necessary to reverse a sheet, on the one side of which an image is formed, and to convey the sheet to a position where the double-sided sheet is resupplied, it is possible to suppress the size of the apparatus by making a reversing port for reversing this sheet serve also as a sheet discharging port.
[0006] However, in such a one-drum type color image forming apparatus, since it is necessary to perform color image formation by the four rounds of the intermediate transfer material, the productivity of a color output is low in comparison with that of a tandem system.
[0007] Therefore, as shown in U.S. Pat. No. 6,204,927, for example, in regard to an image in A4 size or letter (LTR) size which is sheet size generally used in an office, the decrease of productivity is suppressed as much as possible by outputting two images at a time by performing two sheets of image formation on an intermediate transfer material while the intermediate transfer material, having the peripheral length enabling image formation in A3 size, takes one round (thereinafter, this is called “two-sheet affixing” or “two-affix”).
[0008] As described above, in color image formation, the two-sheet affixing is performed in principle to form two sheets of images so that they may exist concurrently.
[0009] However, in the two-sheet affixing, since two images on the intermediate transfer material are close, a sheet interval between two sheets on which these images should be transferred must be conveyed with approaching with each other. On the other hand, in the case of the double-sided image formation accompanied by reversal in a sheet discharging port, a sheet interval between the sheet, being reversed, and a sheet following the sheet being reversed should be such that the subsequent sheet may be conveyed to the sheet discharging port after the reversal operation of the sheet being reversed is completed. Therefore, if control is such that the two-sheet affixing is performed in the order of sheets being ready for image formation, there arises a problem that the reversal of the sheet in the sheet discharging port cannot be performed.
[0010] Nevertheless, if image formation is performed in a one-sheet affixing mode in all pages, there is a problem that productivity falls remarkably.
SUMMARY OF THE INVENTION
[0011] In view of the above problems, the present invention is devised, and aims at providing an image forming apparatus which can return the control to form two images on one round of an intermediate transfer material without causing interference between sheets, even if there arises the case that two images cannot be formed on one round of the intermediate transfer material by various factors at the time of image formation.
[0012] Another object of the present invention is to provide an image forming apparatus characterized in comprising a photosensitive member, an intermediate transfer material, a first transfer device which transfers an image, formed on the above-mentioned photosensitive member, on the intermediate transfer material, a second transfer device which transfers on a sheet the above-mentioned image formed on the intermediate transfer material, a feed device which feeds the sheet to the above-mentioned second transfer device, a refeed device which refeeds the sheet, on which the image is transferred by the above-mentioned second transfer device, to the above-mentioned second transfer device with reversing the sheet, and a controller which executes selectively a first mode, in which one image is formed on one round of the above-mentioned mid-transfer material, and a second mode in which two images are formed on one round of the above-mentioned mid-transfer material, that the above-mentioned controller makes an image, which should be formed on a sheet refed by the above-mentioned refeed device, formed on a first half area on one round of the above-mentioned mid-transfer material, and makes an image, which should be formed on a sheet fed by the above-mentioned feed device, on a second half area on one round of the above-mentioned mid-transfer material when executing the above-mentioned second mode when performing image formation on both sides of a sheet, and that the above-mentioned controller executes the above-mentioned first mode before returning to the above-mentioned second mode after executing the above-mentioned first mode instead of executing the above-mentioned second mode when performing image formation on both sides of a sheet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 is a schematic structural diagram showing an image forming apparatus according to an embodiment of the present invention;
[0014] [0014]FIG. 2 is a schematic diagram showing the control structure of an image forming apparatus according to an embodiment of the present invention;
[0015] [0015]FIG. 3 is a block diagram showing the flow of an image signal in an image processing unit according to an embodiment of the present invention;
[0016] [0016]FIG. 4 is an explanatory diagram explaining double-sided image formation order according to an embodiment of the present invention;
[0017] [0017]FIG. 5 is a flow chart explaining image formation control according to an embodiment of the present invention;
[0018] [0018]FIG. 6 is an explanatory diagram explaining double-sided image formation control according to an embodiment of the present invention; and
[0019] [0019]FIG. 7 is an explanatory diagram explaining the timing of primary transfer and secondary transfer according to an embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Hereafter, an image forming apparatus according to the present invention will be explained in detail with reference to drawings.
[0021] (Embodiments)
[0022] [0022]FIG. 1 is a schematic sectional diagram of a full-color image forming apparatus (compound machine having a copy function, a printer function and a FAX function) of this embodiment.
[0023] Reference numeral 1 denotes a digital color image reader, and 2 denotes a digital color image printer.
[0024] The full-color image forming apparatus of this embodiment has the digital color image reader 1 in an upper portion, and has the digital color image printer 2 in a lower portion.
[0025] First, the structure of the digital color image reader 1 will be explained.
[0026] Reference numeral 100 denotes a control unit controlling the entire image forming apparatus, 101 denotes original sheet table glass (platen), and 102 denotes an automatic document feeder (ADF) which feeds an original sheet to the original sheet table glass automatically.
[0027] In addition, a specular surface pressure plate or a white pressure plate (not shown) can be also mounted instead of this automatic document feeder 102 .
[0028] Light sources 103 and 104 which illuminate an original sheet include light sources such as halogen lamps, fluorescent lamps, and xenon tube lamps.
[0029] Reflectors 105 and 106 condense the light of the light sources 103 and 104 on an original sheet.
[0030] Reference numerals 107 to 109 denote mirrors, 110 denotes a lens, and 111 denotes a CCD image sensor (a charge coupled device image sensor, and hereafter, this is referred to as a “CCD”). The lens 110 condenses the light reflected from an original sheet or projection light on the CCD 111 .
[0031] Reference numeral 112 denotes a board on which the CCD 111 is mounted, and 113 denotes a digital image processing unit.
[0032] Reference numeral 114 denotes a carriage which contains the light sources 103 and 104 , reflectors 105 and 106 , and mirror 107 .
[0033] Reference numeral 115 denotes a carriage which contains the mirrors 108 and 109 .
[0034] In addition, the carriage 114 and carriage 115 scan the entire surface of an original sheet by mechanically moving at velocity V and velocity V/2 respectively in a sub-scanning direction Y which is orthogonal to an electric scanning direction (main scanning direction X) of the CCD 111 .
[0035] Reference numeral 116 denotes an external I/F with other devices, and specifically, the external I/F 116 can be connected to a facsimile machine (not shown), a LAN I/F device (not shown), etc. In addition, the control of communication procedures of image information and code information with a facsimile machine or a LAN I/F device is performed by the two way communication between a control unit (not shown) of each connected apparatus and a CPU 301 .
[0036] The digital color image printer 2 will be explained later.
[0037] Next, the structure of a control unit 100 will be explained by using FIG. 2.
[0038] [0038]FIG. 2 is a schematic diagram showing the structure of the control unit 100 of the image forming apparatus according to the present invention.
[0039] Reference numeral 250 denotes a printer control unit, 301 denotes the CPU which is control means, 302 denotes a memory, and 303 denotes an operation unit.
[0040] The operation unit 303 is constituted by a liquid crystal with a touch panel for inputting the contents of process execution by an operator, and reporting information and a warning about processing to the operator.
[0041] The control unit 100 , as shown in FIG. 2, comprises the CPU 301 with an interface (hereafter, “I/F”) which exchanges information for performing control to a digital image processing unit 113 and a printer control unit 250 respectively, the operation unit 303 and memory 302 .
[0042] Next, the digital image processing unit 113 and control unit 100 will be explained in detail.
[0043] [0043]FIG. 3 is a block diagram showing the detailed structure that the digital image processing unit 113 and control unit 100 output image signal data to the printer control unit 250 .
[0044] Reference numeral 502 denotes a clamp & Amp & S/H & A/D unit and 503 denotes a shading unit, 504 denotes a connection & MTF correction & original sheet detection unit, and 505 denotes an input masking unit. Reference numeral 506 denotes a selector, and 507 denotes a color space compression & background removal & log conversion unit. Reference numeral 508 denotes a delay unit, 509 denotes a moire removal unit, 510 denotes a variable-magnification process unit, 511 denotes a UCR& masking & black character reflection unit, 512 denotes a γ-correction unit, 513 denotes a filter unit, 514 denotes a page memory unit, 515 denotes a background removal unit, and 516 denotes a black character determination unit.
[0045] An original sheet on the original table glass reflects light from the light sources 103 and 104 , and the reflected light is led to the CCD 111 to be converted into an electrical signal (when the CCD 111 is a color sensor, it is sufficient that R, G and B color filters are put in line on the one-line CCD in the order of R, G and B, that an R filter, a G filter, and a B filter are arranged respectively on the three-line CCD, or that a filter is an on-chip filter or a filter is separated from the CCD).
[0046] Then, the electrical signal (analogue image signal) is inputted into the digital image processing unit 113 , and is given a sample-and-hold operation (S/H) in the clamp & Amp & S/H & A/D unit 502 to clamp a dark level of the analogue image signal to reference potential, amplified up to a predetermined amount (the above-mentioned processing order is not always the order of the notation), and A/D converted into, for example, R, G and B 8-bit digital signals.
[0047] Then, the R, G and B signals are given shading correction and black correction in the shading unit 503 . Thereafter, the connection & MTF correction & original sheet detection unit 504 corrects in the connection processing signal timing so that reading positions of three lines may become the same by adjusting a delay amount every line according to each reading rate since the reading positions between lines are different from one another when the CCD 111 is a three-line CCD; corrects in the MTF correction changes in reading MTF since the reading MTF changes by the reading rate or variable-magnification rate; and recognizes in the original sheet detection an original sheet size by scanning the original sheet on the original table glass in original sheet detection.
[0048] The digital signals corrected in the reading position timing are corrected in the spectral characteristic of CCD 111 and the spectral characteristic of the light sources 103 and 104 , and reflectors 105 and 106 by the input masking unit 505 .
[0049] An output of the input masking unit 505 is inputted into the selector 506 , and it is switchable with an external I/F signal.
[0050] The signal outputted from the selector 506 is inputted into the color space compression & background removal & log conversion unit 507 and background removal unit 515 .
[0051] After the signal inputted into the background removal unit 515 is given the background removal, it is inputted into the black character determination unit 516 which determines whether it is a black character of the original sheet on the original sheet, and a black character signal is generated from the original sheet.
[0052] In addition, the color space compression & background removal & log conversion unit 507 into which another output of the selector 506 is inputted determines in the color space compression whether the read image signal is within the range which is reproducible by the printer. If it is within the range, the image signal is kept as it is, but if not, the image signal is corrected so that it may go into the range where the printer can reproduce the image signal.
[0053] Then, the unit 507 performs background removal processing and converts R, G and B signals into Y, M and C signals in a log conversion unit.
[0054] Thereafter, in order to correct timing with the signal generated by the black character determination unit 516 , the output signal of the color space compression & background removal & log conversion unit 507 is adjusted for its timing in the delay unit 508 .
[0055] Moire in two kinds of signals from the black character determination unit 516 and delay unit 508 is removed by the moire removal unit 509 , and the two kinds of signals are given variable-magnification processing in the main scanning direction by the variable-magnification process unit 510 .
[0056] Then, in the UCR & masking & black character reflection unit 511 , the signal processed by the variable-magnification process unit 510 is processed in the UCR processing so that Y, M, C and K signals may be generated from the Y, M and C signals. In the masking processing unit, the signals are corrected so as to be suitable for the outputting of the printer. Further, in the black character reflection unit, the determination signal generated by the black character determination unit 516 is fed back to the Y, M, C and K signals.
[0057] The signal processed by the UCR & masking & black character reflection unit 511 is given smoothing and edge processing by the filter unit 513 after being given density adjustment by the γ-correction unit 512 .
[0058] The image data information processed as described above is once stored in the page memory 514 in the control unit 100 is transmitted to the printer control unit 250 as each image data signal with being synchronized with each video clock by turns according to image writing reference timing of each color from the printer control unit 250 .
[0059] Next, with returning to FIG. 1, the structure of the digital color image printer 2 will be explained.
[0060] [0060]FIG. 1 shows a laser scanner 201 which is latent image forming means, a photosensitive drum 202 which is a photosensitive member, a multi-color developer 203 which consists of developing means and development switching means, and a primary transfer roller 204 which is first transfer means.
[0061] The laser scanner 201 , photosensitive drum 202 and multi-color developer 203 constitute image forming means.
[0062] Reference numeral 205 denotes an intermediate transfer material (or mid-transfer material), 206 denotes a secondary transfer roller which is second transfer means, 207 denotes a pressure roller, 208 , 209 , 210 and 211 denote cassettes, 212 , 213 , 214 and 215 denote sheet supply rollers, and 216 , 217 , 218 and 219 denote sheet separation rollers. Furthermore, reference numeral 220 denotes a manual sheet supply roller, 221 denotes a registration roller, 222 , 223 , 224 and 225 denote vertical path convey rollers, 230 denotes a cleaning blade, 231 denotes a blade, 232 denotes a waste toner box, 233 denotes a sheet discharging roller which is a sheet discharging port also serving as a reversing port, 234 denotes a double-side path, and 240 denotes a manual supply tray.
[0063] In FIG. 1, the printer control unit 250 receives the control signal from the CPU 301 in the control unit 100 which is a control unit of the entire image forming apparatus.
[0064] According to the control signal such as a print start from the control unit 100 , the printer control unit 250 performs the print control of the digital color image printer 2 .
[0065] The laser scanner 201 scans a laser beam, corresponding to the image data signal, in the main scanning direction by a polygon mirror, and radiates the beam to the photosensitive drum 202 .
[0066] An electrostatic latent image formed on the photosensitive drum 202 arrives in a sleeve position of one color in respective colors of a four-color developing rotary by the clockwise revolution of the photosensitive drum 202 .
[0067] Toner according to an amount of electric potential formed between a surface of the photosensitive drum 202 , having the electrostatic latent image, and a developing sleeve surface where a developing bias is applied is flown from the multi-color developer 203 to the surface of the photosensitive drum 202 . Hence, the electrostatic latent image on the surface of the photosensitive drum 202 is developed.
[0068] A toner image formed on the photosensitive drum 202 is transferred by the clockwise revolution of the photosensitive drum 202 to the intermediate transfer material 205 which rotates counterclockwise (primary transfer).
[0069] In the case of a black monochrome image, image formation is performed to the intermediate transfer material 205 by turns with providing a predetermined time interval (primary transfer).
[0070] In the case of a full color image, the sleeve alignment of the developing rotary is performed sequentially every color. Then, the electrostatic latent image corresponding to each color on the photosensitive drum 202 is given the development and primary transfer. After four revolutions of the intermediate transfer material 205 , that is, when the primary transfer of four colors (yellow (Y), magenta (M), cyan (C) and black (K)) is completed, the primary transfer of the full color image is completed.
[0071] On the other hand, a sheet is supplied by each of sheet feed rollers 212 , 213 , 214 and 215 for respective cassette stages from each of cassettes (an upper stage cassette 208 , a lower stage cassette 209 , a third stage cassette 210 and a fourth stage cassette 211 ). The sheet conveyed by each of the sheet separation rollers 216 , 217 , 218 and 219 for respective cassette stages is conveyed to the registration roller 221 by the vertical path convey rollers 222 , 223 , 224 and 225 .
[0072] In the case of manual supply, a sheet loaded or Stacked on a manual supply tray 240 is conveyed to the registration roller 221 by the manual supply roller 220 .
[0073] Then, the sheet is conveyed between the intermediate transfer material 205 and secondary transfer roller 206 in the timing when the transfer to the intermediate transfer material 205 is completed.
[0074] Thereafter, the sheet is stuck to the intermediate transfer material 205 by pressure while it is conveyed toward the fixing device with being inserted between the secondary transfer roller 206 and mid-transfer material 205 . Further, the secondary transfer of four colors of toner images on the intermediate transfer material 205 is performed to the sheet.
[0075] The toner images transferred to the sheet are heated and pressurized by a fixing roller and the pressure roller 207 , and are fixed to the sheet.
[0076] In addition, in regard to transfer-residual toner on the intermediate transfer material 205 which remains without being transferred on the sheet, the cleaning blade 230 which can contact and be released contacts to the surface of the intermediate transfer material 205 and scrapes the transfer-residual toner from the surface of the intermediate transfer material 205 , which is cleaned by the post-process control in the last half of the image forming sequence.
[0077] In the photosensitive drum unit, the residual toner is scraped from the surface of the photosensitive drum 202 by the blade 231 , and is conveyed to the waste toner box 232 which is integrated in the photosensitive drum unit.
[0078] Furthermore, in regard to residual toner with positive and negative polarities on the surface of the secondary transfer roller 206 where the residual toner may be adsorbed, the residual toner with respective polarities is made adsorbed on the intermediate transfer material 205 by applying a secondary transfer normal bias and a secondary transfer reverse bias by turns. Next, by scraping the residual toner by the above-described cleaning blade 230 , the residual toner is cleaned completely, and then, post-processing control is finished.
[0079] The sheet on which the image is fixed is ejected via the sheet discharging roller 233 .
[0080] In double-sided image formation, in order that the sheet on which the image being fixed is laid is given reversal processing outside the apparatus through the sheet discharging roller 233 , an edge of the sheet is once ejected to the discharging port, and the sheet stops with leaving the rear edge by a predetermined distance inside the apparatus.
[0081] That is, a reversal start command is waited in the state of leaving the rear edge of the sheet in a position apart by the predetermined distance from the sheet discharging roller 233 , which is a reversal standby position, so as to reverse and lead the sheet to the double-side path 234 .
[0082] When the reversal start command is issued, the sheet currently waiting in the reversal standby position is reversed by the sheet discharging roller 233 , and is conveyed from the reversal standby position to the double-side standby position through the double-side path 234 .
[0083] After the sheet conveyed through the double-side path 234 is detected by a double-side sensor, the sheet advances by the predetermined distance, and thereafter, once waits in the double-side standby position.
[0084] Then, when a second-side image of both-sided ones becomes ready and a sheet resupply command is issued, the sheets currently waiting in the sheet resupply position is conveyed to the registration roller 221 for secondary image formation. Then, the second-side image of both-side ones is formed.
[0085] At the time of full color image formation, images for two sheets are formed on one round (or full circumference) of the intermediate transfer material 205 (two-sheet affixing) as it can do according to the fact that sheet size is small such as A4 or letter size (LTR). It is also possible to perform such control that images for three or more sheets can be formed on the intermediate transfer material 205 according to the peripheral length of the intermediate transfer material 205 and sheet length.
[0086] In this embodiment, control is performed so that the length in the subscanning direction may be made suitable for arranging and forming images for two sheets on one round of the intermediate transfer material 205 in the case of sheets below LTR size (=216 mm).
[0087] Then, at the time of single-sided image formation, the images which are arranged on one round of the intermediate transfer material 205 and formed for two sheets are transferred one at a time for two sheets supplied from the same one of the cassettes 208 , 209 , 210 and 211 .
[0088] In addition, at the time of double-sided image formation, the images are transferred one at a time for the sheet, which is waiting in the double-side standby position on the double-side path 234 and on whose one side the image has been already formed, and a sheet which is supplied from a cassette. That is, at the time of double-sided image formation, images which are arranged and formed on one round of the intermediate transfer material 205 is two of an image which should be formed on the sheet currently waiting in the double-side standby position on the double-side path 234 , and an image which should be formed on a sheet supplied from a cassette.
[0089] In this case, in regard to the double-sided image formation, another side image (image to the sheet from a sheet resupply unit) of double-sided image data one of which has been already formed on one side, and another side image (image to the supplied sheet) of the double-sided image data which has not been given image formation yet are formed alternately.
[0090] In addition, in regard to an image to a sheet having the size larger than LTR size such as B4, A3 or A4R, since it is not possible to arrange and form images for two sheets on one round of the intermediate transfer material 205 , only the image for one sheet is formed on one round of the intermediate transfer material 205 .
[0091] Next, the image formation order at the time of double-sided image formation will be explained by using FIG. 4.
[0092] [0092]FIG. 4 is a diagram of explaining the order of images which should be formed on the intermediate transfer material (or mid-transfer material) 205 for explaining the image formation order at the time of double-sided image formation. The length or distance for one round of the intermediate transfer material 205 is as shown in the figure, and two or more rounds of the intermediate transfer material 205 are shown in the figure. In addition, let a first half of one round of the intermediate transfer material 205 be an area A, and let a last half be an area B, in the following description.
[0093] Here, 1 α denotes a front side of a first sheet, 1 β denotes a back side of the first sheet, 2 α denotes a front side of a second sheet, 2 β denotes a back side of the second sheet, 3 α denotes a front side of a third sheet, 3 β denotes a back side of the third sheet, 4 α denotes a front side of a fourth sheet, and 4 β denotes a back side of the fourth sheet. In addition, G 1 , G 2 , G 3 , G 4 , G 5 , G 6 , G 7 and G 8 denote images, G 1 , G 3 , G 5 and G 7 denote the images on a front side of each sheet, and G 2 , G 4 , G 6 and G 8 are the images on a back side of each sheet. Moreover, the number applied to G of G 1 to G 8 expresses the page number of an image.
[0094] [0094]FIG. 4 shows an example in the case of forming images for eight sheets in both sides of four sheets.
[0095] In the full color image formation in both sides in this embodiment, it is possible to make two sheets, on whose one side images have been already formed respectively, wait in two standby positions (the double-side standby position and reversal standby position). Hence, double-sided image formation is performed with circulating images for three sheets in combination with a sheet in a sheet supplying position.
[0096] Image formation order at that time, as shown in FIG. 4, is first to form images for first and last two sheets (corresponding to the images G 2 and G 4 and images G 5 and G 7 , respectively) of double-sided image formation in the area A on the intermediate transfer material 205 in a one-sheet affixing mode. Then, third and later images are formed in a two-sheet affixing (or two-affix) mode where an image (odd-numbered image) to a sheet currently waiting in the sheet resupply position in principle is formed in the area A on the intermediate transfer material 205 , and an image (even-numbered image) to a sheet waiting in the sheet supply position (or the predetermined position after sheet supply) is formed in the area B on the intermediate transfer material 205 .
[0097] Owing to this, it is possible to perform the reversal operation in the sheet discharging unit with preventing the decrease of productivity. That is, the two-sheet affixing prevents the decrease of productivity. However, when the two-sheet affixing of G 2 and G 4 is performed, a sheet 2 β where G 4 is formed rushes in to a place where a sheet 1 β where G 2 is formed is being reversed in the sheet discharging unit. Hence, it becomes not possible for the sheet 1 β to be reversed. Then, it becomes possible to avoid this problem by making G 2 and G 4 in the one-sheet affixing (or one-affix) mode and making images after G 1 in the two-sheet affixing mode.
[0098] In addition, when the sheet 1 β on which G 2 is formed is reversed and sheet resupply becomes ready, an image which should be formed on the sheet 1 α (back side of the sheet 1 β) is formed. Here, the image G 1 which should be formed on the sheet 1 α is formed in the two-sheet affixing mode with the image G 6 which should be formed on the sheet 3 β supplied from a cassette. However, in this two-sheet affixing, these images are not arranged in order of G 6 and G 1 , but as shown in FIG. 4, are arranged in order of G 1 and G 6 . That is, G 1 is formed in the area A and G 6 is formed in the area B. This reason is as follows. The sheet 1 α on which G 1 is formed is a sheet to be ejected, and the sheet 3 β on which G 6 is formed is a sheet to be reversed and resupplied. Hence, when the sheet 1 α on which G 1 is formed follows the sheet 3 β on which G 6 is formed, the sheet 1 α rushes in when the sheet 3 β is reversed, and hence, the sheet 3 β cannot be reversed. However, when the sheet 3 β on which G 6 is formed follows the sheet 1 β on which G 1 is formed, the sheet 3 β is reversed after the sheet 1 α is ejected. Furthermore, the formation of an image to be formed on the sheet 2 α following the sheet 3 β takes the time for four colors (corresponding to four revolutions of the intermediate transfer material 205 ). Hence, the sheet 2 α never rushes in when the sheet 3 β is reverses, and therefore, the sheet 3 β can be reversed.
[0099] In addition, although FIG. 4 shows the control of one-sheet affixing and two-sheet affixing, and the control of the order of images at the time of the two-sheet affixing, gaps between sheets in the horizontal axis of FIG. 4 are different from the actual ones. Hence, actual gaps between sheets will be explained by using FIG. 7. FIG. 7 shows a state of the primary transfer to the intermediate transfer material 205 , and a state of the secondary transfer from the intermediate transfer material 250 to a sheet in regard to the images G 4 , G 1 and G 6 in FIG. 4, and this is similar for other images. As for the image G 4 , the image is formed in the area A of the intermediate transfer material 205 in the one-sheet affixing mode, and primary transfer of four colors is performed in the order of Y, M, C and K to the intermediate transfer material 205 by four revolutions of mid-transfer materials 205 . Even when the primary transfer of the last color K is performed, the intermediate transfer material 205 continues rotating counterclockwise as it is, and the secondary transfer of the four colors of images on the intermediate transfer material 205 is performed in a position of the secondary transfer roller 206 to the sheet 2 β supplied from a cassette. On the other hand, in the intermediate transfer material 205 , the images G 1 and G 6 are formed in the two-sheet affixing mode (G 1 is formed in the area A and G 6 is formed in the area B) just after the primary transfer of K of G 4 . Then, the primary transfer of four colors is performed in the order of Y, M, C and K to the intermediate transfer material 205 by four revolutions of the intermediate transfer materials 205 . When the primary transfer of the last color K is performed for G 1 and G 6 , the secondary transfer of the image G 1 on the intermediate transfer material 205 is performed to the sheet 1 α resupplied. Then, the secondary transfer of the image G 6 is performed to the sheet 3 β which is supplied from a cassette with following the sheet 1 α. As seen from FIG. 7, the gap between the sheet 2 β and sheet 1 α is large, but the gap between the sheet 1 α and sheet 3 β is narrow.
[0100] Next, the image formation switching processing of the one-sheet affixing and two-sheet affixing at the time of the double-sided image formation which is this embodiment will be explained by using FIGS. 5 and 6.
[0101] [0101]FIG. 5 is a flow chart explaining image formation control according to this embodiment, and FIG. 6 is an explanatory diagram explaining double-sided image formation control according to this embodiment.
[0102] Here, α of 1 α to 7 α denotes a front side of a sheet, β of 1 β to 7 β denotes a back side of a sheet, a number denotes the order of a sheet, and 1 β, 2 β, 6 α and 7 α are omitted in FIG. 6.
[0103] As mentioned above, in principle, an image to a sheet, which is reversed and resupplied, and an image to a sheet which is supplied from a cassette are arranged and formed on one round of the intermediate transfer material 205 when performing full color image formation also at the time of double-sided image formation. However, under the predetermined conditions described below, there arises the case that this pattern collapses and images for two sheets cannot be arranged and formed on one round of the intermediate transfer material 205 .
[0104] For example, the case that, although image data which should be formed on a sheet which is reversed and resupplied is prepared, image data which should be formed on one round of the intermediate transfer material 205 in parallel to this image and should be formed on a sheet supplied from a cassette is not ready (the case that the development to image data from page description language takes time, and the case that data transfer takes time because of the congestion of traffic on a LAN connected to the external I/F 116 ), the case that, for image stabilization, for example, the process for measuring image density (image density measurement processing), cleaning treatment, toner residual-quantity detection processing, etc. (image formation processing for the image stabilization) are required, the case that, in the structure of having a rotary developer like this embodiment, time becomes necessary for rotating a mirror image machine because of the color mode switching from full color image formation to monochrome image formation (change in the color mode), and the like falls under the above-described predetermined conditions.
[0105] In such cases, since it is necessary to insert a process during image formation in the two-sheet affixing mode, it is not possible to form an image so that two images may coexist concurrently, and hence, image formation is performed one by one (one-sheet affixing).
[0106] Then, when the two-sheet affixing becomes possible, recovery to the two-sheet affixing will be again performed.
[0107] This detailed control will be explained on the basis of a flowchart in FIG. 5.
[0108] In FIG. 5, it is first discriminated at step S 501 whether sheet size is suitable for the two-sheet affixing.
[0109] When the size is larger than the LTR size, the two-sheet affixing is not possible, and hence, an image is formed in the one-sheet affixing mode (step S 517 ).
[0110] When the size is the LTR size or smaller, the two-sheet affixing is possible, and next, it is discriminated whether there was any skip processing in previous image formation (step S 502 ).
[0111] Although this skip processing will be described later, it is fundamentally used for recovery processing when a control pattern of the two-sheet affixing collapses, and hence, this skip processing is not usually performed.
[0112] When there was the skip processing, the process goes to step S 512 . When there was no skip processing, the process goes to step S 503 , and it is discriminated whether the previous image was formed in the area A in the two-sheet affixing mode.
[0113] When the previous image was formed in the area A in the two-sheet affixing mode at step S 503 , the process goes to step S 511 and it is controlled so that a current image may be formed in the area B in the two-sheet affixing mode.
[0114] When the previous image was not formed in the area A in the two-sheet affixing mode at step S 503 , the process goes to step S 504 and it is discriminated whether the previous image is formed in the area B in the two-sheet affixing mode.
[0115] When the previous image was formed in the area B in the two-sheet affixing mode at step S 504 , it is controlled so that a current image may be formed in the area A in the two-sheet affixing mode (step S 505 ).
[0116] When the previous image was not formed in the area B in the two-sheet affixing mode at step S 504 , the process goes to step S 506 and it is discriminated whether the current image is an image which should be given single-sided image formation.
[0117] When the current image is the image, which should be given single-sided image formation, at step S 506 , it is controlled so that the current image may be formed in the area A in the two-sheet affixing mode (step S 508 ).
[0118] When the current image is not the image, which should be given single-sided image formation, at step S 506 , that is, is an image which should be given double-sided image formation, the process goes to step S 507 , and t is discriminated whether the current image is an image which should be formed on a sheet from a double-side sheet resupply unit.
[0119] When the current image is the image, which should be formed on the sheet from the double-side sheet resupply unit, at step S 507 , it is controlled so that the current image may be formed in the area A in the two-sheet affixing mode (step S 509 ). When the current image is not the image, which should be formed on the sheet from the double-side sheet resupply unit, that is, when being the image which should be formed to an unrecorded sheet from a cassette, it is controlled so that the current image may be formed in the one-sheet affixing mode (step S 510 ). Here, in the one-sheet affixing mode, it is controlled so that an image is formed in the area A of the intermediate transfer material 205 as described above.
[0120] That is, the flowchart after step S 503 specifically shows the control of forming an image in the two-sheet affixing when the two-sheet affixing is possible, and forming an image in the one-sheet affixing when the two-sheet affixing is impossible.
[0121] Then, as shown in 1 α, 3 β, 2 α and 4 β of FIG. 6, at the time of normal double-sided image formation, images are formed in the two-sheet affixing mode by pairing two of the image to a front side of a sheet from the sheet resupply unit, and the image to a back side of a sheet from sheet supply.
[0122] With seeing each image, this processing performs the processing of step S 505 and step S 511 in FIG. 5 by turns.
[0123] However, there may arise the case that this pattern collapses under various conditions as mentioned above and it becomes impossible to perform formation so that images for two sheets may coexist concurrently.
[0124] Hereafter, recovery processing in this case will be explained.
[0125] For example, if the formation of a current image is not ready in time of two-sheet affixing formation at step S 511 when a preceding image is formed in the area A in the two-sheet affixing mode (step S 503 ), a skip processing flag is set for performing the skip processing (S 511 ).
[0126] At this time, although the preceding image is formed in the area A in the two-sheet affixing mode, an image does not exist in the area B in the two-sheet affixing mode, and hence, actually, the image formation is in the one-sheet affixing mode (a portion in which an image to a sheet from the sheet resupply unit is formed in the one-sheet affixing mode in 3 α of FIG. 6).
[0127] The flowchart shown in FIG. 5 is executed again after image formation of the current image becomes ready. That is, the skip processing flag which was set at step S 502 is discriminated. If the skip processing flag is set, it is discriminated at step S 512 whether the current image is an image which should be given single-sided image formation.
[0128] This skip processing flag is cleared after being discriminated at step S 502 . In the example of FIG. 6, the current image is an image which should be given the double-sided image formation, and hence, the process goes to step S 514 .
[0129] At step S 514 , it is discriminated whether the current image is an image which should be formed on a sheet from the sheet resupply unit.
[0130] When the current image is the image, which should be formed on the sheet from the sheet resupply unit, at step S 514 , the process goes to step S 515 , and the current image is formed in the area A in the two-sheet affixing mode.
[0131] When the current image is the image, which should not be formed on the sheet from the sheet resupply unit, at step S 514 , the process goes to step S 516 , and the current image is formed in the one-sheet affixing mode (corresponding to 5 β in FIG. 6).
[0132] That is, the flowchart after step S 512 specifically shows the control of performing recovery under the limit that an image which should be formed on a sheet which will be reversed and resupplied from the sheet discharging port is formed not in the two-sheet affixing mode but in the one-sheet affixing mode.
[0133] In the example shown in FIG. 6, since it is determined at step S 514 that the image (current image) to a back side 5 β of a fifth sheet is not the image to the sheet from the sheet resupply unit, the process goes to step S 516 .
[0134] Then, the recovery of the two-sheet affixing pattern is performed by processing the image in the one-sheet affixing mode at step S 516 ( 5 β in FIG. 6).
[0135] That is, the image after being given recovery in the one-sheet affixing mode is given the skip processing at step S 502 , and hence, is returned to the image formation processing to the area A in the two-sheet affixing mode at step S 509 . Thereafter, an image to a sheet from the double-side sheet resupply unit and an image to a sheet from the sheet supplying side are formed by turns.
[0136] As described above, even if there arises the case that images cannot be formed so that two images may coexist concurrently on the intermediate transfer material because various factors act at the time of image formation, it is possible to prevent the decrease of productivity by returning to the two-sheet affixing pattern without causing interference between sheets.
[0137] In the double-sided image formation, it is possible to prevent the decrease of double-side productivity by performing image formation by a double-side circulation amount by returning to the two-sheet affixing pattern without causing interference between sheets.
[0138] In addition, if the image next to the current image is an image which should be formed on a sheet from the double-side sheet resupply unit, at steps S 505 , S 509 and S 515 , not only the current image is formed in the area A in the two-sheet affixing mode, but also the skip flag is set. Owing to this, the last two images in the double-sided image formation are formed substantially in the one-sheet affixing mode, respectively.
[0139] As explained above, according to this embodiment, in a one-drum type image forming apparatus, it is possible to provide an image forming apparatus which can prevent the decrease of productivity by returning to the two-sheet affixing pattern without causing interference between sheets, even if there arises the case that images cannot be formed so that two images may coexist concurrently on the intermediate transfer material because various factors act at the time of image formation. | An image forming apparatus including a photosensitive member, an intermediate transfer material, a first transfer device which transfers on the intermediate transfer material an image formed on the photosensitive member, a second transfer device which transfers on a sheet the image formed on the intermediate transfer material, a feed device which feeds the sheet to the second transfer device, a refeed device which refeeds the sheet, on which the image is transferred by the second transfer device, to the second transfer device with reversing the sheet, and a controller which executes selectively a first mode, in which one image is formed on one round of the intermediate transfer material, and a second mode in which two images are formed on one round of the intermediate transfer material, wherein the controller makes an image, which should be formed on a sheet refed by the refeed device, formed on a first half area on one round of the intermediate transfer material, and makes an image, which should be formed on a sheet fed by the feed device, on a second half area on one round of the intermediate transfer material, in a case of executing the second mode when performing image formation on both sides of a sheet, and wherein the controller executes the first mode before returning to the second mode after executing the first mode instead of executing the second mode when performing image formation on both sides of a sheet. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to a method and apparatus for placing sensors downhole in a well to monitor relevant formation characteristics. Specifically, the sensors can be flowed into the formation in the cement, or other suitable material, used to case the well. Alternatively, the sensors can be physically bored into the formation with a device described herein.
[0003] 2. Description of the Related Art
[0004] Understanding an oil-bearing formation requires accurate knowledge of many conditions, such as critical rock and formation parameters at various points in the zones or formations that the oil bearing formation encompasses. Fluid pressure in the formation, its temperature, the rock stress, formation orientation and flow rates are a few examples of measurements taken within the formation which are useful in reservoir analysis. Having these formation/rock measurements available external to the immediate wellbore in wells within a producing field would facilitate the determination of such formation parameters such as vertical and horizontal permeability, flow regimes outside the wellbores within the formations, relative permeability, water breakthrough condensate banking, and gas breakthrough. Determinations could also be made concerning formation depletion, injection program effectiveness, and the results of fracturing operations, including rock stresses and changes in formation orientation, during well operations.
[0005] In addition to understanding oil bearing formations, the condition of the material used to set casing in a well is of critical interest in monitoring the integrity of a well completion. While cement is commonly used to set casing, other materials such as resins and polymers could be used. So while the term cement is used in this description, it is meant to encompass other suitable materials that might be used now or in the future to set casing. Pressure, temperature and stress, are a few examples of measurements taken within the cement that might be useful in determining the condition of the cement in a well. Various types of transducers placed near the cement/wellbore interface could be used to monitor the condition of the rock or formations outside the wellbore. Having these formation/rock measurements available external to the immediate wellbore in wells within a producing field would facilitate the determination of such formation parameters such as vertical and horizontal permeability, flow regimes outside the wellbores within the formations, relative permeability, potential fines migration, water breakthrough, and gas breakthrough. Determinations could also be made concerning formation depletion, fines migration, injection program effectiveness, and the results of fracturing operations, including rock stresses and changes in formation orientation, during well operations.
[0006] Historically, reservoir analysis has been limited to the use of formation measurements taken within the wellbores. Measurements taken within the wellbore are heavily influenced by wellbore effects, and cannot be used to determine some reservoir parameters. Well conditions such as the integrity of the cement job over time, pressure behind the casing, or fluid movement behind the casing cannot be monitored using the wellbore measurements.
[0007] Therefore, it is desirable to have a method and system that may be used to passively monitor reservoir/formation parameters at all depths and orientations outside a wellbore as well as having a method and system to passively monitor cement integrity. It is further desirable to have a method and system to take these measurements without compromising the casing, cement or any other treatment outside or inside the casing.
SUMMARY
[0008] The present invention provides a method and system that may be used to passively monitor cement integrity and reservoir/formation parameters near the wellbore at all depths and orientations outside a wellbore. These measurements may be taken without compromising the casing, cement or any other treatment outside or inside the casing. In addition, sensors may be deployed in many more locations because of the non-intrusive nature of reading the sensors once they are in place.
[0009] In one embodiment, different types (pressure, temperature, resistivity, rock property, formation property etc.) of sensors are “pumped” into place by placing them into a suspension in the cement slurry at the time a well casing is being cemented. The sensors are either battery operated, or of a type where external excitation, (EMF, acoustic, RF etc.) may be applied to power and operate the sensor, which will send a signal conveying the desired information. The sensor may then be energized and interrogated using a separate piece of wellbore deployed equipment whenever it is desired to monitor cement or formation conditions. This wellbore deployed equipment could be, for example, a wireline tool. Having sensors placed in this way allows many different types of measurements to be taken from the downhole environment. Looking at readings taken at different locations will allow directional properties such as permeability to be examined. Sensors placed close to the wellbore can be used to monitor the well integrity by disclosing information about cement condition, casing wear/condition etc. Sensors placed closer to the cement/wellbore interface provide reservoir or rock property measurements, which may be used in reservoir analysis.
[0010] In another embodiment, the sensors are placed into the formation at or outside the wellbore and may be interrogated whenever it is desired to monitor well or formation conditions. One method of placing the sensors into the formation is to use technology similar to side bore coring tools which remove samples in a direction that is perpendicular to the wellbore. Another method involves placing the sensors into the gravel slurry used for gravel packing and frackpacking operations thus allowing the sensors to migrate into the formation with the fracpack.
[0011] There are many advantages of the proposed system. First, non-intrusive downhole measurements may be taken from numerous locations in the downhole environment. Next, the integrity of the cement job can be closely monitored for initial quality, and degradation with time. Further, many transducers may be placed into the well with relatively low deployment cost. Also, very accurate measurements can be taken because of transducer placement outside the wellbore. Also, very long service life of transducers is achieved because power is supplied by a wellbore device capable of supplying transducer excitation power. Finally, fluid movement and pressure behind the casing may be measured by comparing the many available downhole measurements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
[0013] [0013]FIG. 1 shows a flow chart for placing sensors within the cemented casing of a wellbore.
[0014] [0014]FIG. 2 depicts a wellbore with sensors located within the cemented casing.
[0015] [0015]FIG. 3 shows a flow chart for placing sensors into the formation.
[0016] [0016]FIG. 4 depicts a wellbore and formation with sensors located in the formation.
[0017] [0017]FIG. 5 shows a flow chart for placing a sensor into a formation by drilling laterally away from a wellbore.
[0018] FIGS. 6 A- 6 C depict a tool for drilling away from a wellbore and placing a sensor into a formation.
DETAILED DESCRIPTION
[0019] A presently preferred embodiment of the present invention for placing sensors into a wellbore casing will now be described with reference to FIGS. 1 and 2. FIG. 1 shows a flowchart of a preferred embodiment of a method for placing sensors into a wellbore casing. FIG. 2 illustrates a cross-sectional view of a wellbore and casing with sensors placed therein.
[0020] A wellbore 240 is drilled into the earth using conventional methods and tools well known to those skilled in the art (step 110 ). Sensors 210 are placed into a cement slurry (step 120 ). A casing is placed into wellbore 240 and the cement slurry containing sensors 210 is pumped into wellbore 240 to provide a cemented casing 240 (step 130 ). A wellbore device (not shown in FIG. 2) is then placed into wellbore 240 (step 140 ). Sensors 210 are then interrogated with the well bore device (step 150 ). The wellbore device could be for example a wireline tool or a drill pipe conveyed system. Sensors 210 will typically be transducers which are either battery operated, or of a type where external excitation (EMF, acoustic, RF, etc.) may be applied to power and operate the transducer, which will send a signal conveying the desired information. Sensors 210 may be interrogated whenever desired to monitor cement or formation conditions. Sensors 210 may be of many different types such that many different types of conditions may be monitored. Such monitored conditions include pressure, temperature, resistivity, rock properties, and formation properties. Other monitored conditions include, but are not limited to, paramagnetic properties, magnetic fields, magnetic flux leak, pulse eddy current, and polar spin. Looking at different readings taken at different locations will allow directional properties such as permeability to be examined. Sensors 210 placed close to the wellbore can be used to monitor the well integrity by disclosing information about cement condition, casing wear/condition etc. Sensors 210 placed closer to the cement/wellbore interface provide reservoir or rock property measurements which may be used in reservoir analysis.
[0021] There are many advantages to placing sensors within the cemented well casing. Non-intrusive downhole measurements may be taken from numerous locations in the downhole environment. The integrity, such as micro-annulus, of the cement job can be closely monitored for initial quality and degradation with time. Many sensors may be placed into the well with relatively low deployment cost. Very accurate measurements can be taken because of sensor placement outside of the wellbore. Very long service life of the sensors because the power is supplied by a wellbore device capable of supplying transducer excitation power. Fluid movement and pressure behind the casing may be measured by comparing the many available downhole measurements.
[0022] Turning now to FIGS. 3 and 4, a method of placing sensors into a formation will be described. FIG. 3 depicts a flow chart for a presently preferred method of placing sensors into a formation. FIG. 4 shows a cross-sectional view of a well bore and formation with sensors located within the formation.
[0023] A wellbore 440 is drilled using conventional techniques and devices well known to one skilled in the art (step 310 ). Formation samples are removed from the formations 420 , 425 , and 430 using for example, a side bore coring tool, in a direction perpendicular to wellbore 440 (step 320 ). The maximum distance bored out with standard coring tools is typically around 4 feet from the wellbore 440 . One example of a side bore coring tool may be found in U.S. Pat. No. 5,209,309 issued to Wilson which is hereby incorporated by reference. Sensors 410 are then placed into the formations 420 , 425 , and 430 (step 330 ). A sensor interrogating device is then placed into the wellbore (step 340 ). Sensors 410 are then interrogated whenever it is desired to gather some information that sensors 410 can gather (step 350 ).
[0024] In one variation of this method, rather than removing formation samples with a side bore coring tool, the formations 420 , 425 , and 430 are fractured and packed with gravel (“fracpacking”). Sensors 410 are placed in the gravel slurry prior to packing the fracture. Thus, sensors 410 are placed outside the wellbore and into the formation. Alternatively, perforations 460 can be made in the wellbore 440 casing and the sensors 410 allowed to migrate outside the wellbore 440 with the gravel slurry. The gravel slurry and fracpacking will be described in more detail below.
[0025] As with sensors 210 , sensors 410 will typically be transducers which are either battery operated, or of a type where external excitation (EMF, acoustic, RF, etc.) may be applied to power and operate the transducer, which will send a signal conveying the desired information. Alternatively, the sensors 410 may be powered using fuel cell or power cell. The fuel cell or power cell may be part of the sensors 410 or built as an addition. Formation movement, noise or fluid flow (i.e. effluent flow) could be used to charge or recharge the cell power source. Sensors 410 may be interrogated whenever desired to monitor cement or formation conditions. Sensors 410 may be of many different types such that many different types of conditions may be monitored. Such monitored conditions include pressure, temperature, resistivity, rock properties, and formation properties. Other monitored conditions include, but are not limited to, paramagnetic properties, magnetic fields, magnetic flux leak, pulse eddy current, and polar spin. Sensors 410 placed close to the wellbore 440 can be used to monitor the well integrity by disclosing information about cement condition, casing wear/condition etc. Sensors 410 placed further into a formation or other surrounding substrate will provide very accurate reservoir or rock property measurements.
[0026] It should be noted that sensors 210 and 410 may be calibrated before placement and may be recalibrated after placement in the formation or well casing. For example, a radio or acoustic signal may be sent to each or sensors 210 or 410 , after placement, initiating a calibration response in each of sensors 210 or 410 .
[0027] There are many advantages to placing sensors outside the wellbore. Non-intrusive downhole measurements may be taken from numerous locations in the downhole environment. Very accurate measurements can be taken because of optimal transducer placement outside the wellbore Very long service life of transducers because power is supplied by a wellbore device capable of supplying transducer excitation. Direction formation properties may be measured by comparing the many available downhole measurements.
[0028] The particulate material utilized in accordance with the present invention to carry sensors 410 into formations 420 , 425 , and 430 is preferably graded sand which is sized based on a knowledge of the size of the formation fines and sand in an unconsolidated subterranean zone to prevent the formation fines and sand from passing through the gravel pack. The graded sand generally has a particle size in the range of from about 10 to about 70 mesh, U.S. Sieve Series. Preferred sand particle size distribution ranges are one or more of 10-20 mesh, 20-40 mesh, 40-60 mesh or 50-70 mesh, depending on the particle size and distribution of the formation fines and sand to be screened out by the graded sand.
[0029] The particulate material carrier liquid utilized, which can also be used to fracture the unconsolidated subterranean zone if desired, can be any of the various viscous carrier liquids or fracturing fluids utilized heretofore including gelled water, oil base liquids, foams or emulsions. The foams utilized have generally been comprised of water based liquids containing one or more foaming agents famed with a gas such as nitrogen. The emulsions have been formed with two or more immiscible liquids. A particularly useful emulsion is comprised of a water-based liquid and a liquified normally gaseous fluid such as carbon dioxide. Upon pressure release, the liquified gaseous fluid vaporizes and rapidly flows out of the formation.
[0030] The most common carrier liquid/fracturing fluid utilized heretofore which is also preferred for use in accordance with this invention is comprised of an aqueous liquid such as fresh water or salt water combined with a gelling agent for increasing the viscosity of the liquid. The increased viscosity reduces fluid loss and allows the carrier liquid to transport significant concentrations of particulate material into the subterranean zone to be completed.
[0031] A variety of gelling agents have been utilized including hydratable polymers which contain one or more functional groups such as hydroxyl, cis-hydoxyl, carboxyl, sulfate, sulfonate, amino or amide. Particularly useful polymers are polysaccharides and derivatives thereof which contain one or more of the monosaccharides units galactose, mannose, glucoside, glucose, xylose, arabinose, fructose, glucuronic acid or pyranosyl sulfate. Various natural hydratable polymers contain the foregoing functional groups and units including guar gum and derivatives thereof, cellulose and derivatives thereof, and the like. Hydratable synthetic polymers and co-polymers which contain the above mentioned functional groups can also be utilized including polyacrylate, polymeythlacrylate, polycrylamide, and the like.
[0032] Particularly preferred hydratable polymers, which yield high viscosities upon hydration at relatively low concentrations, are guar gum and guar derivatives such as hydroxypropylguar and carboxymethylguar and cellulose derivatives such as hydroxyethylcellulose, carboxymethylcellulose and the like.
[0033] The viscosities of aqueous polymer solutions of the types described above can be increased by combining cross-linking agents with the polymer solutions. Examples of cross-linking agents which can be utilized are multivalent metal salts or compounds which are capable of releasing such metal ions in an aqueous solution.
[0034] The above described gelled or gelled and cross-linked carrier liquids/fracturing fluids can also include gel breakers such as those of the enzyme type, the oxidizing type or the acid buffer type which are well known to those skilled in the art. The gel breakers cause the viscous carrier liquids/fracturing fluids to revert to thin fluids that can be produced back to the surface after they have been utilized.
[0035] The creation of one or more fractures in the unconsolidated subterranean zone to be completed in order to stimulate the production of hydrocarbons therefrom is well known to those skilled in the art. The hydraulic fracturing process generally involves pumping a viscous liquid containing suspended particulate material into the formation or zone at a rate and pressure whereby fractures are created therein. The continued pumping of the fracturing fluid extends the fractures in the zone and carries the particulate material into the fractures. Upon the reduction of the flow of the fracturing fluid and the reduction of pressure exerted on the zone, the particulate material is deposited in the fractures and the fractures are prevented from closing by the presence of the particulate material therein.
[0036] As mentioned, the subterranean zone to be completed can be fractured prior to or during the injection of the particulate material into the zone, i.e., the pumping of the carrier liquid containing the particulate material through the slotted liner into the zone. Upon the creation of one or more fractures, the particulate material can be pumped into the fractures as well as into the perforations and into the annuli between the sand screen and shroud and between the shroud and the well bore.
[0037] In another presently preferred embodiment, sensors are placed into a formation by drilling laterally away from a borehole. FIG. 5 shows a flow chart of this method. FIGS. 6 A- 6 C depict an instrument suitable for performing this method. As used herein, drilling laterally away from a borehole means in a direction greater than zero degrees away from the general longitudinal (as opposed to radial) direction of the borehole at that particular location and, thus, can include drilling up or down away from the borehole when the longitudinal direction of the borehole is horizontal with respect to the earth's surface. Furthermore, there is no requirement that drilling laterally away from a borehole mean normal or perpendicular to the surface of the wellbore.
[0038] A borehole 602 is drilled using conventional methods well known to one skilled in the art (step 510 ). A sensor placement device 600 is then placed into the borehole 602 (step 515 ). Sensor placement device 600 consists of tubing 650 , a fluid diverter 634 , a control line 692 , outer tubing 636 , pistons 630 and 631 , a sensor 622 , a nozzle 632 , a deflector 610 , and a wire 624 . Tubing 650 is lowered into the borehole 602 from the earth's surface 693 . Tubing 650 may be coiled tubing of a type well known to one skilled in the art.
[0039] Attached to tubing 650 are fluid diverters 634 . An opening 652 allows fluid to flow from tubing 650 through fluid diverters 634 and into control line 692 which is attached to fluid diverters 634 by Swagelok fittings. At the end of control tube 692 are two pistons 630 and 631 . Pistons 630 and 631 provide an offset area for pressure to work against so the outer tube 636 (also called a cylinder) will stroke downward upon application of pressure. This is the placement means for sensor 622 . Pistons 630 and 631 are rigidly attached to fluid or flow diverters 634 . In one embodiment, pistons 630 and 631 may be a smaller size of control line than outer tubing 636 . Although described herein with reference to two pistons, multiple pistons may be used as well and may be deployed in a variety of directions, such as, for example, up, down, or at an angle, without departing from the scope and spirit of the present invention.
[0040] Overlying control line 692 is outer tubing 636 . Outer tubing 636 is pushed onto pistons 630 and 631 and remains in a retracted position until pressure is applied. Upon application of pressure, nozzle 632 provides a jetting action for the fluid, which effectively cuts through the formation. As nozzle 632 erodes the formation material, the outer tubing 636 is allowed to move downwards. Sensor 622 is attached to the inside of outer tubing 636 by a threaded carrier sub that has an open ID to allow fluid to bypass to nozzle 632 . Outer tube 636 has a nozzle 632 at one end. Sensor 622 is attached to outer tubing 636 , either by integration into the housing wall or surface mounting, and is connected to wire 624 that connects sensor 622 to a surface electronics 690 . Surface electronics 690 may include a recorder to record the data received from sensor 622 for later processing possibly at a remote site and may also include processing equipment to process the data received from sensor 622 as it is received. Furthermore, surface electronics 690 may be attached to display devices such as a cathode ray tube (CRT) or similar computer monitor device and/or to a printer.
[0041] After sensor placement device 600 has been placed down hole (step 515 ), the fluid pressure inside tubing 650 is increased (step 520 ). The pressure may be increase by, for example, a pump on the surface is connected to the coiled tubing 650 , which provides the high pressure source required to operate the drilling operation or by a subsurface powered pump. The increased fluid pressure causes fluid to flow through opening 652 into fluid diverter 634 which diverts fluid into control line 692 causing sensor pods 680 to extend (step 525 ). Water may be used as the working fluid unless this will adversely affect the formation sandface. In such event, a conventional mud may be used. The fluid may also be a treated liquid comparable with the reservoir to minimize formation damage and may possibly be enhanced with friction reducing polymers and abrasives to enhance jet drilling efficiency. The fluid flows from control line 692 into outer tubing 636 . The fluid exits outer tubing 636 through nozzle 632 . The fluid exiting through nozzle 632 cuts through the surrounding rock, thus drilling the sensor pod 680 into place as housing 636 continues to extend exerting pressure on sensor pod 680 (step 530 ). Deflector 610 causes sensor pod 680 to be deflected outward into the formation 604 .
[0042] The surface 612 of deflector 610 can have an angular 611 displacement away from the surface of tubing 650 of just greater than zero degrees to almost 90 degrees depending on the direction an operator wishes to place sensor pod 680 . The greater the angular 611 displacement, the more sensor pod 680 will be deflected away from tubing 650 such that an angular 611 displacement of almost 90 degrees will result in the sensor pod being deflected in a direction almost perpendicular to the surface of tubing 650 . Deflector 610 may be constructed from any suitably hard material that will resist erosion. For example, alloy stainless steel is an appropriate and suitable material from which to construct deflector 610 . Typically, deflector 610 is welded to the base pipe and deflector 610 has a port drilled through it to allow fluid passage.
[0043] Once sensor pod 680 has been drilled into the formation 604 , control line 692 may be retracted out leaving sensor pod 680 in the formation (step 535 ). By leaving control line 692 in place rather than removing it after sensor placement, wire 624 may be better protected. Sensor 622 remains connected to surface electronics 690 via wire 624 . Wire 624 can be an electric wire capable of carrying electronic signals or it can be a fiber optic cable.
[0044] It should be noted that sensor 622 may be recalibrated after placement of sensor 622 downhole in the formation. Such calibration may be accomplished, for example, by means of transmissions via wire 624 or may be through radio and/or acoustic signals.
[0045] To aid in understanding the present invention, refer to the following analogy. Consider a garden hose with a nozzle attached to the end. With the end of the nozzle pushed into the ground, increase the water pressure in the garden hose. The water exiting the nozzle provides an effective drilling tool that allows the hose to be pushed into the ground. This is the principle behind the present invention. The outer tubing will stroke downwards as the formation material is removed. The wire attached to the sensor must have enough length to accommodate the stoke length of the cylinder. The wire may feed through the deflector and continue up the outside of the coiled tubing. This may be useful if the coiled tubing is removed after sensor placement. Otherwise as discussed above, the wire will remain inside the coiled tubing where it is better protected.
[0046] Although the present invention has been described primarily with reference to interrogating the sensors with a wireline tool, other methods of interrogating the sensor may be utilized as well without departing from the scope and spirit of the present invention. For example, the sensors could be interrogated by something built into the completion or by a reflected signal that could power up and interrogate the sensor or sensors.
[0047] The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated. | A method and system to passively monitor cement integrity and reservoir/formation parameters near the wellbore at all depths and orientations outside a wellbore. Different types (pressure, temperature, resistivity, rock property, formation property etc.) of sensors are “pumped” into place by placing them into a suspension in the cement slurry at the time a well casing is being cemented, by placing them in gravel pack used in frackpacking, or by a deflected drilling tool. The sensors are either battery operated, or of a type where external excitation, (EMF, acoustic, RF etc.) may be applied to power and operate the sensor, which will send a signal conveying the desired information. The sensor is then be energized and interrogated using a separate piece of wellbore deployed equipment whenever it is desired to monitor cement or formation conditions. This wellbore deployed equipment could be, for example, a wireline tool. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an ophthalmologic apparatus which can compound the result of the measurement of the field of view of an eye to be examined and relates a corresponding eye fundus image, and to a method of compounding the image of the eye to be examined.
2. Related Background Art
Perimeters have heretofore been widely used to measure the fields of view of examinees. The outline of such perimeters will hereinafter be described with reference to FIG. 11 of the accompanying drawings. FIG. 11 illustrates a perimeter and its measuring state. The perimeter is fixedly constructed on a table 1 so that the inner surface of a substantially hemispherical dome 2 faces an examinee A and the outer surface of the dome 2 faces an examiner B. The examinee A has his face fixed by a fixing member 3 provided on the inner surface of the dome. The examinee A responds as to whether he could recognize an index presented successively on the inner surface while watching a fixation target on the inner surface of the dome 2. The examiner presents an index on the inner surface of the dome 2 while monitoring the gazing point of the examinee A by means of a loupe 4 provided on the outer surface side of the dome 2, and manually records the result of the response on recording paper 5 disposed on the table 1. FIG. 12 shows an example of the format of a view field chart on the recording paper 5, and the result of the response is plotted by the help of the view field chart printed on the recording paper 5, for example, the view field chart C comprising a plurality of concentric circles and four axes in directions to divide these concentric circles into eight parts. Besides this method, use has been made of a method using a TV monitor, instead of the recording paper 5, to plot measuring points on a view field chart on the TV monitor.
Heretofore, when determining the correspondence between this output result and the fundus of the eye to be examined, the examiner had to compare the photograph of the eye fundus with view field data with his eyes on the basis of the information of the center of the field of view and the blind spot portion of the field of view this was inefficient.
On the other hand, there is also known an eye fundus perimeter in which the view field measuring function is added to the eye fundus photographing function and a photographing output having the result of view field measurement imprinted on an eye fundus image is obtained. This perimeter is such that infrared light is applied to an eye to be examined and the examiner moves the index of visible light while observing the infrared eye fundus image of the eye fundus image on a TV monitor, and plots by means of a pen on a light-transmitting recording plate mounted in the apparatus or plots by perforating recording paper, in accordance with the examinee's response, and the plot image, together with the infrared eye fundus image, is displayed on the TV monitor and simultaneously with the photographing of the fundus of the eye, a final plot image is imprinted on the photograph. This is described in detail, for example, in U.S. Pat. No. 4,279,478.
However, in this prior-art eye fundus perimeter, the eye fundus image capable of being displayed is only the eye fundus image in real time during the view field measurement, and the past eye fundus images or the like cannot be displayed. That is, for example, even if there is a desire to measure the field of view while observing the eye fundus image before a disease has been cured, it is impossible with such a the prior-art type device.
Also, the eye fundus image produced by infrared light is not clear and further, infrared light penetrates more deeply into the interior of the fundus of the eye than visible light and therefore, the resultant infrared image is an image of the deeper portion of the fundus than the visible image, and this has led to the problem that such image differs from the outermost eye fundus image.
Also, during long-time view field measurement, it has been necessary to apply infrared light to an eye to be examined.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an ophthalmologic apparatus which can obtain a compound image of view field data and a corresponding eye fundus image at any point in time differing from the point in time of view field measurement.
It is another object of the present invention to provide an ophthalmologic apparatus by which view field measurement is possible while the examiner is watching an eye fundus image at any point in time differing from the point in time the view field measurement (for example, an eye fundus image in the past before a disease of the eye has been cured).
It is still another object of the present invention to provide an ophthalmologic apparatus by which view field measurement is possible while the examiner is watching an eye fundus photograph image by visible light.
It is yet still another object of the present invention to provide an ophthalmologic apparatus by which view field measurement is possible without the use of infrared light while the examiner is watching a corresponding eye fundus image.
It is a further object of the present invention to provide an ophthalmologic apparatus by which view field measurement is possible while the examiner is watching a clear-cut corresponding eye fundus image.
It is still a further object of the present invention to provide an ophthalmologic apparatus which can obtain a compound image of a distortion-free eye fundus image of an eye to be examined and corresponding view field data.
It is yet still a further object of the present invention to provide an ophthalmologic apparatus which can obtain a compound image of a wide angle of view.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the construction of a first embodiment of the present invention.
FIG. 2 shows an example of the output of the first embodiment.
FIG. 3 shows the construction of a second embodiment of the present invention.
FIG. 4 shows the construction of a third embodiment of the present invention.
FIG. 5 shows an example of the output of the third embodiment.
FIG. 6 shows the construction of a fourth embodiment of the present invention.
FIG. 7 illustrates the correction of the distortion of an eye fundus image.
FIG. 8 illustrates the making of a panorama eye fundus image.
FIG. 9 illustrates the compounding of an eye fundus image and a view field chart.
FIG. 10 shows an example of an eye fundus image having a morbid part.
FIG. 11 shows the whole of a perimeter according to the prior art.
FIG. 12 shows an example of the format of the view field chart.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(Embodiment 1)
FIG. 1 shows the construction of a first embodiment of the present invention, and more particularly shows the perspective construction of the recording table 10 of a view field meter. Incorporated in the table 10 is an optical system for projecting onto recording paper an eye fundus image photographed by the use of light from a photographing light source which emits visible light. This optical system comprises, in succession from the light source 11, a removably mounted slide film 12 upon which the eye fundus image falls, a relay lens 13, a reflecting mirror 14, a magnification changing lens 15, a projection lens 16 and a reflecting mirror 17 disposed in the optical path. The table 10 has an upper portion thereof formed of a light-transmitting member such as a glass plate, and recording paper 18 is interchangeably placed on that portion.
The slide film 12 on which the eye fundus image of an eye to be examined has been photographed in advance is illuminated by the light source 11. This light enters the magnification changing lens 15 via the relay lens 13 and the reflecting mirror 14. The eye fundus image on the slide film 12 is not limited to an image photographed by an ordinary eye fundus camera, but may also be an image which has been distortion-corrected or an eye fundus image of a wide angle of view, as will be described later with respect to Embodiment 4. The slide film 12 is finely movable in vertical and horizontal directions, and alignment is effected so that the projected eye fundus image may coincide with a view field chart C printed on the recording paper 18. The magnification changing lens 15 has its focal length freely variable from the exterior, and is adjusted so as to form an eye fundus image of an appropriate size on the recording paper 18 on the table 10. The light which has left the magnification changing lens 15 projects, via the projection lens 16 and the reflecting mirror 17, the eye fundus image from the back surface of the recording paper 18 having a light-transmitting type screen characteristic.
Since the view field chart C is printed on the recording paper 18, there is obtained a compound image in which the projected eye fundus image and the field chart C overlap each other. The recording paper 18 is freely replaceable and can always be set at the same position if it is in accord with a predetermined format. Even when use is made of recording paper of another different format, it can be freely changed in its position so as to be aligned with the eye fundus image. Usually, the recording paper is disposed so as to correspond to the index presentation position of a view field measuring device in a 1:1 correspondence and therefore, it need not always have a chart printed thereon, and the result view field measurement may be plotted on only the projected eye fundus image.
To make the projected eye fundus image coincident with the view field chart, the slide film 12 and the magnification changing lens 15 are adjusted. As regards alignment, the slide film 12 is moved in vertical and horizontal directions to bring the view field center of the view field chart into coincidence with the yellow spot of the eye fundus image. When there is a deviation between the blind spot of the view field chart found in the course of measurement and the optic disk of the eye fundus image, they are brought into coincidence with each other as required. Also, as regards the adjustment of magnification, the inverse number of the photographing magnification of the eye fundus image recorded on the slide film 12 is set as the projection magnification.
FIG. 2 shows an example of a state in which the result of measurement is being recorded. The view field chart C comprising a plurality of concentric circles and radial straight lines equally dividing these concentric circles and the projected eye fundus image D are compoundly displayed in superposed relationship with each other on the recording paper 18 placed on the table 10 in front of the examiner. The result of the measurement of the view field is successively recorded as plots al-an on the recording paper 18 by the examiner or is automatically recorded by a machine.
(Embodiment 2)
FIG. 3 shows the construction of a second embodiment of the present invention which is a modified form of the above-described embodiment. An opaque material is used as recording paper 19, and an eye fundus image may be projected from above the recording paper 19. A light source 21 is installed above the recording paper 19 placed on a table 20, and a slide film 22, a relay lens 23, a magnification changing lens 24 and a projection lens 25 are disposed in succession on the optical path from the light source 21 toward the table 20. The slide film 22 is finely movable for alignment. These constituents have the same action as the previous embodiment, that is, an eye fundus image can be formed on the recording paper and the eye fundus image can be superposed on the view field chart C on the recording paper 19.
In the constructions of the present and previous embodiments, it is also possible to use the apparatus in such a manner that the view field chart measured and recorded by an ordinary view field meter is mounted on the apparatus of the present or previous embodiment and the examiner makes a diagnosis while watching the compound image of the view field chart and the eye fundus image.
(Embodiment 3)
Referring to FIG. 4 which shows a third embodiment of the present invention. An illuminating system lens 32, an apertured mirror 33 and an objective lens 34 are arranged in succession on an optical path passing through a photographing light source 31 which is an eye fundus photographing means and an eye E to be examined. The apertured mirror 33 is made conjugate with the pupil Ep of the eye E to be examined by the objective lens 34. An imaging lens 35, a beam splitter member 36 and an image pickup device 37 are arranged in succession rearwardly of the apertured mirror 33 so that the eye fundus image may be formed on the image pickup element of the image pickup device 37. The image pickup element may preferably be an area sensor array such as a CCD which will not engender distortion. The output of the image pickup device 37 is connected to an image memorizing device 40, to which is also connected an input device 30 for inputting an eye fundus image from the exterior. The output of the image memorizing device 40 is connected to a display device 38 such as a liquid crystal TV, and a light pen 39 is connected to the display device 38. The output of the image memorizing device 40 is also connected to a video printer 41 and a stimulative light source driving device 42. The stimulative light source driving device 42 is a moving means for a stimulative light source 43, and a light beam from the stimulative light source 43 is adapted to be directed into the optical path to the eye fundus Er through the beam splitter member 36.
In the construction described above, the fundus of the eye to be examined is first photographed before the field of view is measured. During the photographing of the eye fundus, the photographing light source 31 flashes and emits a visible light, which illuminating system lens 32, the apertured mirror 33, the objective lens 34 and the pupil Ep. The eye fundus image is formed on the image pickup element of the image pickup device 37 via the pupil Ep, the objective lens 34, the apertured mirror 33, the imaging lens 35 and the beam splitter member 36 and is memorized in the image memorizing device 40. The image memorizing device 40 memorizes a stationary video signal or digital signals. The content of the image memorizing device 40 is displayed as a stationary eye fundus image Er' on the display device 38.
If desired, photographing of the eye fundus may not be effected by the apparatus of the present embodiment, but the eye fundus image photographed by a discrete eye fundus photographing apparatus may be input from the photographing angle of view, i.e., the magnification, and may be memorized by the image memorizing device 40 and displayed on the display device 38. By doing so, it also becomes possible to accomplish the measurement of the field of view chiefly about a morbid part while watching the past eye fundus image in which, as shown, for example, in FIG. 10, the morbid part (e designates a bleeding spot, and f denotes a white spot) was photographed.
The examiner carries out the measurement of the field of view while watching the stationary eye fundus image being thus displayed, and when the examiner designates a desired view field measuring point on the eye fundus screen of the display device 38 by means of the light pen 39, the stimulative light source driving device 42 moves the stimulative light source 43 in conformity with the coordinates on the screen read by the light pen, i.e., the designated position of the eye fundus image, and a stimulative light is emitted toward the designated measuring point of the eye fundus Er. A stimulating method is, for example, static perimeter. This method is such that the luminance of the stimulative light is visually unrecognizably weak at the beginning and is gradually intensified and at a point of time whereat the examinee visually recognizes the stimulative light, the examinee responds by means of a switch or the like and the then luminance of the stimulative light and the then position of the measuring point are introduced as a measured value and memorized. At this time, view field measurement data are image-compounded and displayed on the display device 38. Various display methods such as displaying a point of a color conforming to the luminance of the stimulative light, and changing the size of the point in conformity with the luminance or the size of the index are within contemplation. In this manner, measurement of numerous positions is progressed, and the final result of the measurement is output to the video printer 41 on the basis of the content of the image memorizing device 40. Without the view field measurement data being displayed on the display device 38, the compound result may be output only to the video printer 41.
FIG. 5 shows an example of the output, and curves a and b are isopters prepared by linking respective measuring points together. These isopters, if classified by color, will become easy to see.
The means for designating the measuring point is not limited to the light pen, but may be one of various well-known input means, and for example, the index may be moved by the use of input means such as a mouth, a track ball, a digitizer, a touch panel or a keyboard.
(Embodiment 4)
FIG. 6 shows the construction of portions for compounding the eye fundus image and view field measurement data, as a fourth embodiment of the present invention, and in this figure, the perimeter and the transfer of the data obtained from the perimeter are omitted. In FIG. 6, the reference numeral 60 designates an eye fundus image input portion for reading and inputting an image in which the eye fundus image of the eye to be examined is recorded, which eye fundus image input portion may, for example, be a 35 mm slide scanner for reading a 35 mm slide and inputting the eye fundus image. The reference numeral 61 denotes a system operation portion for the operator to input a command to the system, the reference numeral 62 designates a view field data input portion for inputting the output signal of view field measuring means which measures the field of view of the eye to be examined, the reference numeral 63 denotes an image operation means for carrying out numerous operations such as image processing and control of the system, the reference numeral 64 designates an image memorizing portion for memorizing the image, the reference numeral 65 denotes a correction function memory portion for memorizing the correction function of the distortions of various eye fundus cameras, and the reference numeral 66 designates an image output portion such as a printer for outputting the compound image of the corrected eye fundus image and the view field data. This image output portion 66 print-outputs the compound image in a color or colors. The reference numeral 67 denotes an image display portion such as a TV monitor for displaying the memorized image in the image memorizing portion 64.
A specific method of carrying out the present embodiment will now be described in detail. First, the eye fundus image recorded on a 35 mm slide prepared in advance is read and input from the image input portion 60, and thereafter is A/D converted and digitally stored into the image memorizing portion 64. In the present embodiment, an example of the 35 mm slide scanner is shown, whereas this is not restrictive, but the image input portion may be, for example, an eye fundus photographing means such as an eye fundus camera having an A/D converting interface, or a means which can provide an eye fundus image, such as a still video camera.
Generally an image photographed by an eye fundus camera or the like has distortion in the marginal portion thereof. So, the distortion of the marginal portion of the input image memorized in the image memorizing portion 64 is digitally corrected as indicated by 13 to 14 in FIG. 7, by the use of the distortion correction function memorized in the correction function memory portion 65, and the corrected image is again stored into the image memorizing portion 64. As a specific example of the method correcting the distortion of the marginal portion of the image, the image is displaced by Δγ calculated from the correction function in each meridian direction from the center of the image. More particularly, each optic axis height, i.e., the displacement Δγ in the meridian direction caused by distortion correspondingly to the position of a radius γ from the center of the image, is measured or calculated in advance, and these are received as distortion data into a memory, and during data processing, the position information of the digital image signal is corrected by an amount corresponding to the displacement Δγ.
The eye fundus image used in the present embodiment is not limited to a photographed image of a narrow angle of view which can be photographed at one time, but may also be a distortion-free panorama eye fundus image of a wide angle of view obtained by combining a plurality of eye fundus images obtained by photographing different regions, as shown in FIG. 8. Nowadays, the angle of view covered by an eye fundus camera at one time is generally of the order of 30°-60°, but this problem can be solved by using a panorama eye fundus image. In this case, a plurality of images are input from the eye fundus image input portion 60 and memorized in the image memorizing portion 64, and correction of distortion and combinating of the images are effected in the image operation means. If correction of distortion is effected before the eye fundus images a, b and c are combined together as shown in FIG. 8, there will occur no deviation of the images due to distortion in the connected portions of the images. The combining of the images can be manually or automatically accomplished from the pattern of blood vessels or the like by the use of a conventional image recognition processing technique.
Thus, the image subjected to distortion correction for the input eye fundus image, or the panorama eye fundus image obtained by combining the plurality of images of displayed on the image display portion 67. The examiner carried out the measurement of the field of view while watching this displayed eye fundus image, and a specific method of compounding the eye fundus image and the view field data will hereinafter be described.
As regards the view field data successively sent from the view field measuring means during the measurement of the field of view, the data are recorded at a corresponding position on the eye fundus image memorized in the image memorizing portion, and are displayed on the image display portion 67 successively, individually or in a postscript fashion. Alternatively, the eye fundus image and all view field data may be compounded at a time after the completion of the measurement.
In FIG. 9, the reference numeral 75 designates the eye fundus image after the distortion of the eye fundus camera has been corrected, the reference numeral 76 denotes the optic disk, and the reference numeral 77 designates a yellow spot. The reference numeral 78 denotes the view field data of the eye to be examined corresponding to the eye fundus image 75, the reference numeral 79 designates the blind spot, and the reference numeral 80 denotes the center of fixation. Here, in the eye fundus image 75 and the image of the view field data 78, the optic disk 76 and the blind spot 79, and the yellow spot 77 and the center of fixation 80, correspond to each other as the same regions. In the image operation means 63, these two points are extracted from the two images by the use of the image recognition processing technique, and the process of adjusting the two images so as to bring the two points into coincidence with each other and superposing the two images one upon the other is carried out.
During the superposition, the eye fundus image 75 and the view field data 78 are in mirror image relationship and therefore, the mirror image inverting process of the view field data 78 is first effected and then the compounding of the images is effected. The mirror image inverting process can be easily accomplished because the view field data 78 is digital data.
When the eye fundus image 75 and the image of the view field data 78 differ in scale and the two points cannot be brought into coincidence with each other at the same time, one of the two images is enlarged or reduced to make the sizes of the two images equal to each other. In the example shown in FIG. 9, the view field data 78 is enlarged. As an example of the processing method in this case, the distance between the optic disk and the yellow spot in the eye fundus image and the distance between the blind spot and the center of the field of view in the view field meter output image are measured, and the total sizes of one or both images are changed so that these two distances may correspond with each other. After the sizes of the both images have corresponded with each other, the respective points are brought into coincidence with each other and the both images are adjusted and compounded. As an alternative method, the centers of the fields of view of the both images and an image of a predetermined angle of view (e.g. 60°) centered at the yellow spot may be extracted and these extracted images may be magnification-changed and compounded so that they may coincide with each other. During the enlargement, it will be more preferable to carry out a picture element interpolation process. Thus, there can be obtained a compound image 81 as shown in the lower portion of FIG. 9 wherein the optic disk and the blind spot coincide with each other at 82 and the yellow spot and the center of the field of view coincide with each other at 83.
As the view field data display method, besides the display method using the isopters of the embodiment, various forms of display such as density display and display by color are possible. | An ophthalmologic apparatus characterized by the provision of a device for introducing thereinto an eye fundus image at a point in time earlier than the point in time of view field measurment, a device for measuring the field of view of an eye to be examined, and a device for superposing the introduced eye fundus image and the output of the view field measuring a device, one upon the other, and compounding them. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a novel process for preparing azidomethylthienylacetic acids and certain esters thereof useful in the synthesis of aminomethylthienylmethylpenicillins and aminomethylthienylmethylcephalosporins. The novel azidomethylthienylacetic acids are prepared by oxidative rearrangement of azidomethylthienylmethyl ketones by thallium (III) nitrate in the presence of methanol or ethanol and certain specified acids to provide the methyl azidomethylthienylacetates when methanol is employed or the corresponding ethyl esters when ethanol is used. The azidomethylthienylacetic acids are obtained by hydrolysis of the esters. The azidomethyl compounds provided by the process of the invention are useful intermediates in the preparation of aminomethylthienylmethylpenicillins and -cephalosporins by acylation of 6-APA, 7-ACA or their derivatives to obtain corresponding azidomethylthienylmethyl compounds which are then converted to the analogous aminomethyl compounds by well-known means. British Pat. No. 1,467,407 (Derwent No. 73775V) discloses a similar process employing amino-protected methyl 5-aminomethyl-2-thienyl ketones to provide the corresponding 2-thienylacetic acids. However, the use of methyl azidomethylthienyl ketones is novel and unexpected in view of the prior art which discloses that alkyl azides are unstable to acids such as those employed in the present process.
2. Description of the Prior Art
McKillop et al., J. Am. Chem. Soc., 93, 4919 (1971) has shown that thallium (III) nitrate in methanol containing perchloric acid converts acetophenones into methyl phenylacetates. However, in defining the limitations of this conversion the author points out that the reaction is unsuccessful when applied to compounds containing an amino group due to preferential complexation of the amino substituent with the thallium electrophile. The corresponding amides are stated to react normally. The above-mentioned British Pat. No. 1,467,407 discloses that amino protected 5-aminomethyl-2-thienylacetic acids may be prepared by reaction of amino protected 2-acetyl-5-aminomethylthiophenes with thallium (III) nitrate in the presence of lower alkanols such as methanol and perchloric acid followed by hydrolysis of the intermediate ester. The use of the amino protected 5-aminomethyl-2-thienylacetatic acids or a reactive functional derivative thereof to acylate certain 7-aminocephalosporanic acids and derivatives thereof followed by removal of the amino protecting group to provide the corresponding 7-(5-aminomethyl-2-thienylmethyl)cephalosporins is also described.
U.S. Pat. Nos. 3,966,710 and 3,997,527 disclose a series of aminomethylarylmethylpenicillins, particularly 6-(phenyl- and thienylacetamido)penicillanic acids and esters substituted in the phenyl and thienyl moieties with an aminomethyl substituent. The aminomethylarylacetic acid intermediates employed, including 2-aminomethyl-3-thienylacetic acid and 3-aminomethyl-2-thienylacetic acid were prepared by conventional synthetic methods. The former compound was prepared from 2-aminomethyl-3-methylthiophene by acetylation, free radical catalyzed bromination to obtain N-acetyl-2-aminomethyl-3-bromomethylthiophene; this intermediate was then converted to the 3-cyanomethyl analog which was hydrolyzed to the desired 3-thienylacetic acid. The isomeric 3-aminomethyl-2-thienylacetic acid was obtained from 2-thienylacetamide via the corresponding N-hydroxymethyl compound, cyclization to 3-aminomethyl-2-thienylacetic acid lactam and hydrolysis.
The amino moiety of the aminomethyl substituted arylacetic acids was protected, preferably by reaction with methyl acetoacetate as taught in U.S. Pat. No. 3,813,376, prior to acylation of 6-APA or its esters.
o-Azidomethylphenylacetic acid and methods for its preparation from o-bromomethylphenylacetate esters are disclosed in U.S. Pat. Nos. 3,766,175; 3,813,391; 3,814,755 and 3,840,535. However, the azidomethylthienylacetic acids and esters are not known in the art.
Abramovitch and Kyba in "The Chemistry of the Azido Group", S. Patai, Editor, Interscience Publishing Co., New York, 1971, Chapter 5, pp. 221-239, record that alkyl azides, including aralkyl azides, are unstable in the presence of protonic acids such as sulfuric, hydrochloric, perchloric and trifluoroacetic acids, especially upon warming. Such azides are also reported to be unstable to Lewis acids such as aluminum trichloride and antimony pentachloride.
SUMMARY OF THE INVENTION
It has now been found that novel compounds of the formula: ##STR1## wherein R is hydrogen or R O where R O is methyl or ethyl are obtained by a novel process which comprises the steps of:
(a) contacting approximately equimolar amounts of a ketone of the formula: ##STR2## and thallium (III) nitrate in the presence of at least a molar excess of an alcohol of the formula R O OH and from about 0.1 to 10 moles of acid per mole of said ketone, said acid being a member selected from the group consisting of perchloric, sulfuric, nitric, toluenesulfonic, methanesulfonic, fluosulfonic and fluoboric acids, at a temperature of from about 0° to 80° C. to obtain a product of formula (I) wherein R is said R O ; and
(b) hydrolyzing said product of step (a) under ester hydrolyzing conditions when a compound of formula (I) wherein R is hydrogen is desired.
The process of the invention is unexpected in view of the prior art which teaches that organic azides such as the above azidomethyl group containing reactants and products of the process are unstable to the strong acids employed. The products provided have advantages over aminomethylthienylacetic acids as intermediates in the synthesis of aminomethylthienylmethylpenicillins and -cephalosporins since the azido containing acids or certain carboxyl derivatives thereof known in the art for acylation of penicillins and cephalosporins may be employed directly without protection of the azido group to provide the corresponding azidomethylthienylmethylpenicillins and cephalosporins, and the azido group subsequently converted to an amino group by simple catalytic hydrogenation. The use of aminomethylthienylacetic acid, on the other hand, requires the use of an amino protecting group and subsequent removal thereof from the penicillin or cephalosporin precursor.
It is a further object of this invention to provide the novel compounds of formula (I), especially 2-azidomethyl-3-thienylacetic acid, 3-azidomethyl-2-thienylacetic acid, 5-azidomethyl-2-thienylacetic acid and the methyl and ethyl esters of each.
DETAILED DESCRIPTION OF THE INVENTION
The process of the present invention may be employed to prepare azidomethylarylacetic acids and derivatives thereof of the general formula ##STR3## wherein R is hydrogen or R o where R o is methyl or ethyl; R 1 is hydrogen, methyl or ethyl; R 2 is hydrogen or alkyl having from one to three carbon atoms; and Ar is ##STR4## wherein R 3 is a member selected from the group consisting of hydrogen, F, Cl, Br, hydroxy and alkoxy having from one to three carbon atoms; and R 4 is a member selected from the group consisting of hydrogen, F, Cl and Br; which comprises contacting approximately equimolar amounts of a ketone of the formula ##STR5## and thallium (III) nitrate in the presence of an alcohol, R o OH and in the presence of certain strong acids.
Particularly preferred, however, is the process for the production of the novel azidomethylthienylacetic acids and esters of the formula ##STR6## wherein R is as defined above.
In carrying out the preferred process the appropriate methyl azidomethylthienyl ketone and thallium (III) nitrate are contacted in the presence of methanol or ethanol which has been acidified with certain strong acids. By "strong acid" within the context of this invention is meant an organic or inorganic acid having a pKa of about 2 or lower. Suitable strong acids are those that allow the desired reaction to take place without substantial production of undesirable by-products. While many such suitable strong acids are available in the art, preferred such acids are perchloric, sulfuric, nitric, toluenesulfonic, methanesulfonic, fluosulfonic and fluoboric acids. An especially preferred acid is perchloric acid for reasons of economy and efficiency.
The above-mentioned ketone starting material and thallium (III) nitrate are preferably contacted in equimolar amounts. However, a molar excess of either reactant may be employed if desired. While the amount of alcohol theoretically required is also equimolar, it is preferable to use at least a molar excess of said alcohol, up to about 100 moles per mole of said ketone, such that the alcohol also serves as a solvent for the reaction.
The mole ratio of the preferred strong acid to said ketone may vary over a wide range from about 0.01 to 100 moles of such acid per mole of said ketone. A preferred range of such acid, however, is from about 0.1 to 10 moles per mole of ketone and an especially preferred range is from about 3 to 5 moles of such acid per mole of said ketone.
The preferred range of temperature for the process of Step (a) is from about 0° to 80° C. At temperatures substantially lower than 0° C. the reaction rate is exceedingly slow. Temperatures above about 80° C. for the reaction require the use of pressure equipment and such high temperatures cause excessive amounts of undesirable by-products to be formed. Of course, as one skilled in the art is aware, within the preferred range of temperature the reaction will proceed faster at higher temperatures and more slowly at lower temperatures. Within the preferred range of temperature the reaction ordinarily is substantially complete in from about 0.5 to 50 hours. A particularly preferred temperature is room temperature, i.e., from about 15° to 30° C., at which temperature the reaction is substantially complete within about 2 to 24 hours.
The process of the invention is illustrated by the following reaction sequence employing methyl 2-azidomethyl-3-thienyl ketone and methanol. ##STR7##
Thallium (I) nitrate precipitates from the reaction mixture as a white solid during the reaction. When the reaction of Step (a) is substantially complete the desired azidomethylthienylacetic acid ester is isolated by standard methods well known in the art. For example, the reaction mixture may be filtered to remove precipitated salt, the filtrate concentrated, diluted with water and concentrated again to ensure complete removal of alcohol. The residue is partitioned between water and a water immiscible solvent such as, for example, ethyl ether, chloroform or benzene, and the organic extracts are washed, dried and evaporated to dryness. The crude residual ester may be used in Step (b) or may be further purified, for example by recrystallization or by column chromatography.
The methyl and ethyl esters provided in Step (a) serve as intermediates which are converted to the desired azidomethylthienylacetic acids by hydrolysis in Step (b). The hydrolysis may be carried out under either alkaline or acidic conditions commonly used in the art for ester hydrolysis. When alkaline conditions are employed, the ester is contacted with aqueous base optionally in the presence of a water miscible organic solvent such as ethanol, methanol or acetone. Examples of bases which may be employed are sodium hydroxide, potassium carbonate and calcium hydroxide. The alkaline hydrolysis may be allowed to proceed at room temperature or may be heated at temperatures up to the reflux temperature. The resulting alkali metal or alkaline earth salt of the azidomethylthienylacetate is acidified and the acid isolated by standard means well known in the art.
When acid hydrolysis is employed, it is preferred that the ester obtained in Step (a) is dissolved in a water miscible organic solvent such as, for example ethanol, methanol, acetone, dimethoxyethane, diethylene glycol dimethyl ether or tetrahydrofuran. An especially preferred such solvent is tetrahydrofuran. To this solution is added an aqueous solution of an acid. While any of the acids ordinarily employed for ester hydrolysis will suffice, preferred such acids are sulfuric, phosphoric and hydrochloric acid. Hydrochloric acid is especially preferred for reasons of efficiency. The acidic hydrolysis is preferably carried out at a temperature in the range of from about room temperature up to the reflux temperature of the solvent. Reflux temperature is particularly preferred to shorten the time required for hydrolysis to about 2 to 8 hours.
When the acid hydrolysis is substantially complete, the reaction mixture is cooled and the desired acid isolated by standard methods well known in the art. For example, the reaction mixture is made alkaline with, e.g., sodium hydroxide or potassium carbonate, the alkaline mixture washed with ether to remove neutral organic material, the aqueous layer acidified and re-extracted with ether. The ether extracts are then evaporated to provide the desired azidomethylthienylacetic acid which is of suitable purity for use in acylation of penicillins or cephalosporins. If desired, however, the azidomethylthienylacetic acid may be further purified by standard means such as by column chromatography.
As will be obvious to one skilled in the art, the acidic reaction mixture from Step (a) may be used in Step (b), after separation of precipitated thallium (I) nitrate, without isolation of the ester. For example, the alcoholic filtrate from the Step (a) reaction mixture may be diluted with water and hydrolyzed as described above either with or without addition of one of the acids preferred for hydrolysis.
The azidomethylthienylacetic acids of the invention or the reactive functional carboxyl derivatives thereof may be used to acylate 6-aminopenicillanic acid (6-APA), its esters, including monosilyl and disilyl-6-APA and other derivatives of 6-aminopenam such as, for example, 6-amino-2,2-dimethyl-3-(tetrazol-5-yl)penam which is disclosed in U.S. Pat. No. 4,026,881 and Belgian Pat. No. 821,163. The acids of formula (I) can likewise be used to acylate 7-aminocephalosporanic acids such as, for example, those of British Pat. No. 1,467,407; U.S. Pat. Nos. 3,766,175; 3,766,176 and 3,814,755, as well as other 7-aminocephem derivatives, for example the 4-(tetrazol-5-yl)-3-cephems of U.S. Pat. No. 3,966,719.
The acylation methods which may be used to provide the above-mentioned azidomethylthienylacetamidopenams and -cephems are well known in the art. For example, the free acids of formula (I) may be employed directly for acylation of the above mentioned 6-aminopenams and 7-aminocephems, in which case a suitable condensing agent, e.g., N,N'-dicyclohexylcarbodiimide, is also employed; or the acid of formula (I) may first be converted into a reactive functional carboxyl derivative, e.g., the acid chloride, acid bromide or mixed anhydride with the ethyl half-ester of carbonic acid which is then condensed with the 6-aminopenam or 7-aminocephem. These and other well known acylation methods which may be employed are described in, e.g., U.S. Pat. Nos. 3,966,719; 4,024,249; Belgian Pat. No. 821,163; British Pat. No. 1,467,407 and Ekstrom et al., Acta. Chem. Scand., 19, 281-299 (1965).
While the azidomethylthienylacetamidopenicillins and corresponding cephalosporins are themselves valuable antibacterial agents, they preferably serve as intermediates to provide the more potent antibacterial aminomethylthienylacetamidopenicillins and cephalosporins such as, for example, those disclosed in U.S. Pat. No. 4,009,160 and British Pat. No. 1,467,407. The azido group is conveniently converted to an amino group by catalytic hydrogenation, while the hydrogenation may be carried out employing any of the catalysts and conditions known to those skilled in the art, it is preferred to employ a palladium catalyst. The palladium catalyst may be supported on, for example, activated carbon or calcium carbonate or may be unsupported palladium powder or palladium formed in situ by reaction of a palladium oxide or salt with hydrogen.
The hydrogenation may be carried out under a wide range of temperature and pressure conditions. However, temperatures in the range of about 0° to 100° C. and especially about 25° to 50° C. are preferred. Preferred pressures for the hydrogenation are from about atmospheric pressure to 5 atmospheres. The hydrogenation is carried out in the presence of a reaction-inert solvent such as, for example, water, ethanol, methanol, tetrahydrofuran, dioxane or mixtures thereof. Ordinarily, the azidomethyl group containing compound dissolved in said solvent is mixed with catalyst, adjusted to a pH of about 6-8 and hydrogenated in a suitable apparatus well known to those skilled in the art. When hydrogen uptake is substantially complete, the catalyst is removed by filtration and the desired aminomethylthienylacetamidopenicillin or -cephalosporin isolated by standard methods, such as, for example, precipitation at the isoelectric point or acidification and extraction into a suitable water immiscible solvent, for example, chloroform or ethyl ether. The isolated antibacterial compound may be purified, if desired, for example, by column chromatography.
Preparation of Starting Materials
2-Acetyl-3-methylthiophene and 2-acetyl-4-methylthiophene are prepared by acetylation of commercially-available 3-methylthiophene with acetic anhydride in the presence of phosphoric acid by the procedure of Hartough and Kosak, J. Am. Chem. Soc., 69, 3093 (1974). Using the same procedure with commercial 2-methylthiophene provides 2-acetyl-5-methylthiophene.
3-Acetyl-2-methylthiophene is obtained by acetylation of 2-thenyl-magnesium chloride by the method of Gaertner, J. Am. Chem. Soc., 73, 3934 (1951). 3-Acetyl-4-methylthiophene is provided by the following reaction sequence: ##STR8## The chlorination step is carried out by the method of Campaigne and LeSuer, J, Am. Chem. Soc., 71, 333 (1949). The acetylation step is carried out in a hydrocarbon solvent in an inert atmosphere. The dehalogenation to provide the desired intermediate is carried out employing a palladium-on-calcium carbonate catalyst by well-known means; see, for example, Freifelder, "Practical Catalytic Hydrogenation", John Wiley and Sons, Inc., New York, 1971.
4-Acetyl-2-methylthiophene is prepared by the reaction of 2-methylthiophene-4-carboxylic acid [Shvedov et al., Khim. Geterotsikl. Soedin., 1010 (1967); Chem. Abstr., 69, 51922j (1968)] with methyl lithium or by reacting the corresponding acid chloride with lithium dimethylcopper or dimethyl cadmium. The acetyl methylthiophenes are converted to the requisite azidomethylthienylmethyl ketones as outlined below for 3-azidomethyl-2-thienylmethyl ketone. ##STR9## The thienyl bromides are obtained by reacting equimolar amounts of the acetyl methylthiophene and N-bromosuccinimide (NBS) and a catalytic amount of α,α-azobisisobutyronitrile (AIBN) in carbon tetrachloride. The mixture is heated at reflux, typically for about 4 hours, and worked up by methods well known to those skilled in the art. The thenyl bromides obtained are reacted with an equimolar amount of sodium azide in aqueous acetone. This step is ordinarily carried out at room temperature for about 2 to 4 hours and the desired product isolated by standard procedures well known in the art.
The following examples are provided to further illustrate the invention. However, they are not to be construed as limitations of this invention, many variations of which are possible without departing from the spirit or scope thereof. In the examples the following abbreviations are used: 1 H NMR for Proton Nuclear Magnetic Resonance Spectra, s for singlet, d for doublet, q for quartet, IR for infrared.
EXAMPLE 1
Methyl 3-Azidomethyl-2-thienylacetate
To a solution of methyl 3-azidomethyl-2-thienyl ketone (20.5 g., 0.113 mole) in 230 ml. of methanol and 46 ml. of 70% aqeuous perchloric acid, was added 55.1 g. (0.124 mole) thallium (III) nitrate trihydrate. A white precipitate of thallium (I) salts soon formed. The resulting mixture was stirred at 20°-25° C. for 24 hours. Sodium chloride, 10.5 g., was added, the suspension stirred for 15 minutes and then filtered. The filtrate was evaporated in vacuo to about half volume, 150 ml. of water was added and the solution evaporated again to remove the remaining methanol. The resulting mixture was diluted with water and extracted three times with 200 ml. portions of diethyl ether. The combined extracts were washed with saturated sodium chloride solution, saturated sodium bicarbonate solution till basic, dried over magnesium sulfate and evaporated to dryness. The residue was filtered through a 1-inch layer of Florisil, washing with chloroform, and the filtrate evaporated to obtain the desired product as an oil, 17.2 g. (72% yield). 1 H--NMR (CDCl 3 ), ppm. (δ): 7.22 (d, J=5, aromatic-H), 7.0 (d, J=5, aromatic-H), 4.35 (s, CH 2 N 3 ), 3.8 (s, CH 2 ), 3.7 (s, OCH 3 ); IR spectrum (film), cm. -1 : 3100, 2100 (N 3 ), 1740 (CO 2 CH 3 ).
EXAMPLE 2
Ethyl 3-Azidomethyl-2-thienylacetate
When an equal volume of ethanol is employed to replace the methanol used in Example 1 and the reaction mixture is heated at reflux for 1 hour then worked up as described in Example 1, the title compound is obtained.
When the above reaction in ethanol is carried out at 0° C. for 3 days the results are substantially the same.
EXAMPLE 3
Methyl 5-Azidomethyl-2-thienylacetate
When the procedure of Example 1 was repeated but employing an equivalent amount of 5-azidomethyl-2-thienylmethyl ketone in place of the 3-azidomethyl isomer used therein, the title compound was obtained as an oil in 53% yield. 1 H--NMR (CDCl 3 ), ppm. (δ): 7.6-6.8 (m, aromatic-H), 4.50 (s, CH 2 ), 3.85 (s, CH 2 ), 3.75 (s, OCH 3 ); IR spectrum (film), cm. -1 : 2950, 2100, 1740, 1450.
EXAMPLE 4
Ethyl 2-Azidomethyl-3-thienylacetate
Methyl 2-azidomethyl-3-thienyl ketone (18.1 g., 0.10 mole) is dissolved in a mixture of 180 ml. of ethanol and 1.0 g. (0.01 mole) of concentrated sulfuric acid. Thallium (III) nitrate trihydrate (44.4 g., 0.10 mole) is added and the mixture is heated at reflux for three hours and allowed to stand overnight at room temperature. The precipitated salt is removed by filtration, the filtrate concentrated in vacuo to a small volume, 125 ml. of water added and the solution again evaporated to a small volume. The resulting residue is partitioned between water and ethyl ether, and the combined ether extracts washed with saturated brine, then saturated sodium bicarbonate solution and dried over magnesium sulfate. The crude title compound is obtained upon evaporation of solvent. Further purification, when desired, is obtained by chromatography on Florisil or Sephadex LH-20.
EXAMPLE 5
When the procedure of Example 4 is repeated, but employing the acid catalyst, reaction temperature and times indicated below, ethyl 2-azidomethyl-3-thienylacetate is similarly obtained.
______________________________________ Mole Ratio ReactionAcid Catalyst Acid Cat./ketone Temp. ° C. Time,Hrs.______________________________________H.sub.2 SO.sub.4 5 50 8HClO.sub.4 10 15 24p-Toluenesulfonicacid, hydrate 3 80 1CH.sub.3 SO.sub.3 H 10 80 0.5FSO.sub.3 H 1 25 30HBF.sub.4 0.1 30 50HNO.sub.3 5 0 50______________________________________
EXAMPLE 6
Methyl 2-Azidomethyl-4-thienylacetate
Methyl 2-azidomethyl-4-thienyl ketone (9.05 g., 0.05 mole), 150 ml. of methanol, 12.0 g. (0.15 mole) of 70% nitric acid and 22.2 g. (0.05 mole) of thallium (III) nitrate trihydrate is heated at reflux for 2 hours, cooled to room temperature, neutralized with dilute sodium hydroxide solution, filtered and the filtrate worked-up as described in Example 4 to obtain the title compound.
EXAMPLE 7
Methyl 4-Azidomethyl-2-thienylacetate
When the procedure of Example 1 is repeated, but employing methyl 4-azidomethyl-2-thienyl ketone as starting material in place of the methyl 3-azidomethyl-2-thienyl ketone used therein, the title compound is obtained in like manner.
EXAMPLE 8
Methyl 4-Azidomethyl-3-thienylacetate
When the procedure of Example 1 is repeated but employing methyl 4-azidomethyl-3-thienyl ketone as starting material in place of the methyl 3-azidomethyl-2-thienyl ketone used therein, the title compound is similarly obtained.
EXAMPLE 9
3-Azidomethyl-2-thienylacetic Acid
Methyl 3-azidomethyl-2-thienylacetate (15.6 g., 0.074 mole) was dissolved in 200 ml. of tetrahydrofuran and 30 ml. of 3M hydrochloric acid was added. The solution was heated at reflux for 5 hours, then cooled and adjusted to pH 10 with 10% (by weight) sodium hydroxide solution. The alkaline mixture was washed with 3 × 250 ml. of diethyl ether, the aqueous layer adjusted to pH 2 and extracted with 3 × 250 ml. of the same solvent. The combined ether extracts were dried and evaporated to dryness to obtain 10.5 g. (72% yield) of the desired acid as a solid. 1 H--NMR (CDCl 3 ), ppm. (δ): 9.35 (broad singlet, CO 2 H), 7.15 (d, J=5, 2 aromatic-H), 4.35 (s, CH 2 N 3 ), 3.85 (s, CH 2 CO 2 --); IR spectrum (CHCl 3 ), cm. -1 : 2100, 1700, 1400, 1250, 860, 700.
Hydrolysis of ethyl 3-azidomethyl-2-thienylacetate by the above procedure or by employing an equal volume of 6M sulfuric acid or 8M phosphoric acid in place of the 3M hydrochloric acid also affords the title compound.
When 0.05 mole of methyl 3-azidomethyl-2-thienylacetate is refluxed for two hours in a mixture of 200 ml. of methanol and 15 ml. of 5N sodium hydroxide, then 100 ml. of water added, the alcohol evaporated in vacuo, the residue acidified and extracted with ether, 3-azidomethyl-2-thienylacetic acid is similarly obtained.
EXAMPLE 10
5-Azidomethyl-2-thienylacetic Acid
Methyl 5-azidomethyl-2-thienylacetate (21.1 g., 0.10 mole) was dissolved in 300 ml. of tetrahydrofuran and 40 ml. of 3M hydrochloric acid was added. After heating at reflux for 6 hours the reaction mixture was cooled and the product isolated as described in Example 9 to obtain a 62% yield of oil. 1 H--NMR (CDCl 3 ), ppm. (δ): 9.0 (s, COOH), 6.85 (s, 2 aromatic-H), 4.4 (s, CH 2 N 3 ), 3.75 (s, CH 2 COO); IR spectrum (neat, cm. -1 : 3000 (broad), 2100 (N 3 ), 1710 (CO 2 H), 1680 and 1475.
EXAMPLE 11
Hydrolysis of the methyl and ethyl esters provided in Examples 4 to 8 under the conditions indicated below in each case similarly provides the following azidomethylthienylacetic acids.
__________________________________________________________________________ Acid Temp., Time, Product Solvent* Catalyst ° C. Hrs.__________________________________________________________________________ ##STR10## THF 6M HCl 50 8 ##STR11## ethanol 2M H.sub.2 SO.sub.4 78 4 ##STR12## CH.sub.3 OCH.sub.2 CH.sub.2 OCH.sub.3 5M H.sub.3 PO.sub.4 82 3 ##STR13## methanol 6M H.sub.2 SO.sub.4 50 18 ##STR14## THF 3M HCl 65 6 ##STR15## Diglyme 3M H.sub.2 SO.sub.4 100 2 ##STR16## THF 6M HCl 65 2__________________________________________________________________________ *THF is tetrahydrofuran; Diglyme is diethylene glycol dimethyl ether.
EXAMPLE 12
6-(3-Azidomethyl-2-thienylacetamido)penicillanic Acid
6-Aminopenicillanic acid (4.93 g., 0.023 mole) was dissolved in a mixture of 100 ml. each of water and tetrahydrofuran, adjusted to pH 7.5 with 10% aqueous sodium hydroxide solution and cooled to 0° C. At this temperature was added 3-azidomethyl-2-thienylacetic acid (4.5 g., 0.023 mole) followed by 4.4 g. (0.023 mole) of 1-ethyl-3-(3-diemthylaminopropyl)carbodiimide hydrochloride. The pH of the mixture was adjusted to 5.8 and maintained at 0° to 5° C., pH 6.0-6.1 for 3 hours, adding 3N hydrochloric acid as required. The tetrahydrofuran was removed by evaporation in vacuo, the aqueous residue adjusted to pH 8 and washed with ethyl acetate. The aqueous phase was acidified (pH 2.0) and extracted with 3 × 50 ml. of ethyl acetate. The combined extracts were dried over sodium sulfate and evaporated in vacuo to obtain 5.7 g. (63%) of the title compound as a foamed solid; 1 H--NMR (CDCl 3 ), ppm (δ): 7.8 (d, NH), 7.1 (q, 2 aromatic-H), 3.8 (s, CH 2 ), 1.5 [2s, C(CH 3 ) 2 ]; IR spectrum (KBr), cm -1 : 2105 (N 3 ), 1786 (β-lactam). The compound was found to have an in vitro minimum inhibitory concentration (MIC) vs. Step. pyogenes 1.56 μg./ml.
EXAMPLE 13
6-(3-Aminomethyl-2-thienylacetamido)penicillanic Acid
6-(3-Azidomethyl-2-thienylacetamido)penicillanic acid, 1.97 g., was dissolved in 3 ml. of dioxane and 100 ml. of water was added. To the resulting aqueous solution, 0.8 g. of 10% palladium on carbon catalyst was added, the mixture adjusted to pH 6 and hydrogenated with shaking at 45 p.s.i. (3.16 kg./cm 2 ). At 15 minute intervals the mixture was adjusted to pH 6 with 3N hydrochloric acid. When hydrogen uptake was complete the catalyst was removed by filtration, the filtrate adjusted to pH 5.5 and freeze-dried to obtain 1.48 g. (80%) of the desired product. A portion was purified by column chromatography on Sephadex LH-20, eluting with distilled water; M.P. 195°-215° C. (dec.); 1 H--NMR (D 2 O) 7.4 (q, 2-aromatic H), 5.5 (m, 2H, 5 and 6 position), 4.3 (s, CH 2 ), 4.0 (s, CH 2 ), 1.65 (s, CH 3 ), 1.5 (s, CH 3 ); IR spectrum (KBr),, cm -1 : 1786, 1666, 1600; in vitro minimum inhibitory concentration (MIC) vs. Strep. pyogenes ≦0.1 μg./ml.
PREPARATION A
Acetyl Thenylbromides
i. Methyl 3-Bromomethyl-2-thienyl ketone
A mixture of methyl 3-methyl-2-thienylketone (14 g., 0.10 mole), N-bromosuccinimide (18 g., 0.10 mole), α,α-azobisisobutyronitrile (AIBN, 0.3 g.), and carbon tetrachloride (300 ml.) was heated cautiously to reflux under a nitrogen atmosphere. After stirring 4 hours at reflux, the mixture was cooled, filtered to remove succinimide, washed first with sodium bicarbonate solution, then with saturated sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was evaporated at reduced pressure to obtain a pale yellow solid which was recrystallized from hexane to obtain 16 g. (73%) of the desired product as colorless crystals, M.P. 62°-64° C. 1 H--NMR (CDCl 3 ), ppm. (δ): 7.5 (d, J=5, aromatic-H), 7.2 (d, J=5, aromatic-H), 4.9 (s, CH 2 Br) and 2.55 (s, CH 3 ). This compound is a strong irritant.
ii. Methyl 5-Bromomethyl-2-thienyl ketone
Employing methyl 5-methyl-2-thienylketone as starting material in the above procedure provided the title compound in 70% yield, M.P. 58°-59° C. 1 H--NMR(CDCl 3 ), ppm (δ): 7.5 (d, J=4, aromatic-H), 7.1 (d, J=4, aromatic-H), 4.65 (s, CH 2 Br), 2.55 (s, CH 3 ).
iii.
Employing the appropriate acetylmethylthiophene in the above procedure the following compounds are similarly obtained:
methyl 2-bromomethyl-3-thienyl ketone
methyl 2-bromomethyl-4-thienyl ketone
methyl 4-bromomethyl-2-thienyl ketone
methyl 4-bromomethyl-3-thienyl ketone.
PREPARATION B
Methyl Azidomethylthienyl Ketones
i. Methyl 3-Azidomethyl-2-thienyl Ketone
To a solution of methyl 3-bromomethyl-2-thienyl ketone (5 g., 0.023 mole) in 42 ml. of acetone and 4 ml. of water was added sodium azide (1.56 g., 0.024 mole) with caution (exothermic!). The resulting solution was stirred at room temperature for 2.5 hours, the acetone evaporated, the residue diluted with water and extracted with diethyl ether. The combined extracts were washed with water, saturated sodium bicarbonate solution and saturated sodium chloride solution, dried over magnesium sulfate and the dried extracts evaporated to dryness to obtain 4.0 g. (97%) of yellow oil. 1 H--NMR (CDCl 3 ), ppm. (δ): 7.5 (d, J=5, aromatic-H), 7.2 (d, J=5, aromatic-H), 4.75 (s, CH 2 N 3 ), 2.5 (s, CH 3 ); IR spectrum (film, cm. -1 : 3100, 2100 (N 3 ), 1660, 1525 and 1420.
ii. Methyl 5-Azidomethyl-2-thienyl Ketone
Employing methyl 5 -bromomethyl-2-thienyl ketone as starting material in the above procedure, the title compound was obtained in 94% yield as an amorphous solid. 1 H--NMR (CDCl 3 ), ppm. (δ): 7.6 (d, J=4, aromatic-H), 7.1 (d, J=4, aromatic-H), 4.6 (s, CH 2 ), 2.5 (s, CH 3 CO); IR spectrum (CHCl 3 ), (cm -1 ): 3000, 2975, 2870, 2100, 1675, 1460 and 1370.
iii.
Employing the appropriate methyl bromomethylthienyl ketone selected from those provided in Preparation A, part iii, the following compounds are obtained in a like manner:
methyl 2-azidomethyl-3-thienyl ketone
methyl 2-azidomethyl-4-thienyl ketone
methyl 4-azidomethyl-2-thienyl ketone
methyl 4-azidomethyl-3-thienyl ketone.
PREPARATION C
Methyl-4-methyl-3-thienyl Ketone
i. Methyl 2,5-Dichloro-4-methyl-3-thienyl Ketone
To a solution of 56.6 g. (0.315 mole) 2,5-dichloro-3-methylthiophene [prepared by the method of Campaigne and LeSeur, J. Am. Chem. Soc., 71, 333 (1949)] and 43.6 ml. (0.614 mole) of acetyl chloride in 165 ml. of petroleum ether under a nitrogen atmosphere was added 48 g. (0.36 mole) of anhydrous aluminum chloride. The mixture was stirred overnight at room temperature, then poured onto ice and extracted with ethyl ether. The combined organic layers were dried, evaporated to dryness and distilled at reduced pressure to yield 49 g. (74%) of the dichloroketone, boiling at 74°-78° C. (0.1 mm.); 1 H--NMR (CDCl 3 ), ppm. (δ): 2.6 (s, CH 3 ), 2.25 (s, CH 3 CO).
ii.
A solution of 26.4 g. (0.126 mole) of methyl 2,5-dichloro-4-methyl-3-thienyl ketone in 180 ml. of ethanol is mixed with 5 grams of 10% palladium-on-calcium carbonate and hydrogenated at 3-4 atmospheres hydrogen pressure in a Parr hydrogenation apparatus until hydrogen uptake is complete. The catalyst and salts are removed by filtration and the filtrate evaporated to dryness in vacuo to obtain the title compound.
PREPARATION D
Methyl 2-Methyl-4-thienyl Ketone
2-Methylthiophene-4-carboxylic acid (14.2 g., 0.1 mole) prepared by the method of Shvedov et al., Khim. Geterotsikl. Soedin. 1010 (1967); Chem. Abstrs., 69, 51922j (1968) in 250 ml. of ethyl ether is cooled to -10° to 0° C. and an ethereal solution of methyl lithium (4.4 g., 0.2 mole) is added dropwise while maintaining the reaction mixture below 0° C. After stirring for 1 hour at 0° C., a solution of 4 g. of water in 100 ml. of ethanol is added cautiously and the mixture allowed to warm to room temperature. The desired product is then isolated by partitioning the reaction mixture between ether and water and evaporation of the organic extracts. | Azidomethylarylacetic acids and derivatives thereof are prepared by oxidative rearrangement of the corresponding azidomethylarylmethyl ketones effected by thallium (III) nitrate in the presence of methanol or ethanol and certain acids to obtain methyl or ethyl esters of the desired azidomethylarylacetate. When desired, the acids are obtained by hydrolysis of said esters. The azidomethylarylacetic acids are valuable intermediates in the preparation of aminomethylarylmethylpenicillins and aminomethylarylmethylcephalosporins. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to methods and apparatus for reducing the rate at which fatigue cracks grow in structures and more particularly to a method and apparatus for reducing fatigue crack growth in an aluminum alloy aircraft structure.
2. Description of the Related Art
The aluminum alloy sheet materials used in aircraft structural components are subject to repeated loadings which, in some circumstances, cause cracks to form by the process of metal fatigue. Such cracks grow slowly with increasing time and service, finally reaching a critical length of crack that can cause rapid propagation and catastrophic failure of an aircraft. Load surges such as those that can occur because of turbulent air or impact on landing may have some influence on crack growth, but the main cause of continuing crack growth is the stress produced by pressurization of the aircraft at high altitude.
Government regulations call for the airlines to make regular inspections for the formation and growth of cracks by several means, such as by sight or use of electronic devices. As planes become older, for example after twenty years or more, the number of pressurization and depressurization cycles involved will have been sufficient to produce cracks that will continue to grow at ever increasing rates. These cracks can eventually cause sudden catastrophic failure of a critical part of the aircraft, and in some extreme cases can cause complete destruction of an airborne aircraft. Government regulations call for replacement of parts when an inspection shows that a crack or cracks have grown to what has been determined from experience to be a potentially dangerous length. At present, there is no known method for stopping crack growth or for significantly reducing the rate at which cracks grow.
The present invention provides a relatively simple and inexpensive means for greatly retarding crack growth rates, and in some cases, for actually stopping the growth of a crack in an aluminum alloy sheet material.
SUMMARY OF THE INVENTION
The present invention is a method and apparatus for reducing the fatigue crack growth rate of cracks in the aluminum alloy fuselage skin of an aircraft structure. The first step involves identifying a fatigue crack in the skin. The crack has a tip defining the direction of crack propagation. The second step involves producing temperature differentials between a narrow strip of the skin and portions of the skin adjacent to this narrow strip. The narrow strip extends from the crack tip to a predetermined distance forward the crack tip. The temperature differentials produced between the narrow strip and adjacent unheated portions of the aircraft skin are sufficiently high so that the expansion due to heating causes plastic flow to occur in the heated strip. The plastic flow results in a residual tensile stress which acts in the direction of propagation when the system is returned to a normal service temperature. This residual tensile stress is of a sufficient magnitude to effectively retard the crack growth rate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 contains curves of constant amplitude fatigue crack growth in aluminum alloys.
FIG. 2 is a schematic illustration of the apparatus of the present invention.
FIG.3 illustrates plots of yield strength versus temperature for four aluminum alloys.
FIG. 4 is a typical line slope which has been generated from the family of fatigue crack growth curves illustrated in FIG. 1.
The same elements or parts throughout the figures are designated by the same reference characters.
DETAILED DESCRIPTION OF THE INVENTION
The following theoretical considerations are presented to provide the reader with a clear understanding of the principles embodying the present invention. The rate of crack growth may be specified by da/dN, which is the change in length, a, for a single cycle of load. A plot of da/dN vs. ΔK (the stress intensity range) is shown in FIG. 1, which is reproduced from MECHANICAL PROPERTIES AND PHASE TRANSFORMATIONS IN ENGINEERING MATERIALS--the Earl R. Parker Symposium on Structure-Property Relationships; 1986; FIG. 4; Page 276. The rate of crack growth with increasing ΔK is essentially linear on the log-log plot, except at very low and very high stress intensity levels, and the plots for all aluminum alloy sheet materials fall in a relatively narrow band. Note the important nature of the plot; a decrease in stress intensity from 10 to 5, for example, corresponds approximately to a tenfold decrease in the crack growth rate. Thus, if the stress intensity (due to a service load) at the tip of a crack in the skin of an airplane could be reduced by a factor of two, the growth rate of the crack would be reduced to one-tenth of the former rate.
Reducing the service load stress to one-half would produce this effect, but this is impossible to do. No practical means has heretofore been devised to drastically reduce crack growth rates in aircraft structures. The present invention provides a new method for altering the local stress state at the tip of a growing crack in such a way that crack propagation will be greatly minimized.
FIG. 2 illustrates a portion of the skin of the fuselage of an aircraft. Typically, a fatigue crack 10 originates at a rivet 12 interconnecting two sheets 14, 16 of aluminum alloy aircraft sheet material. Each sheet is typically 1/16 inch thick. Just forward the tip of the crack 10 there is a region in the metal that has undergone plastic flow because of the high stress concentration produced by the presence of the crack. The stress level at the outer boundary of the plastic zone is at the yield stress of the alloy. This stress level is, for example, two to three times the value of the nominal service stress that exists in the regions far removed from the tip of the crack. To retard crack growth, the effect of the high stress near the tip of the crack must be reduced by a significant amount. (Ideally, if a local residual longitudinal compressive stress, equal in magnitude to the yield strength could be introduced, the net stress would be zero and the crack would cease to grow. However, there seems to be no simple way to introduce such a residual compressive stress, so the solution to the problem of retarding crack growth must come from a different approach.)
The present invention entails the introduction of a width direction residual tensile stress which can be induced in the aluminum alloy sheet at and near the crack 10 and extends a significant distance in the uncracked sheet forward of the crack.
This successful solution of the problem is based on the microscopic nature of the crack growth process in aluminum and its alloys. Such materials do not fracture on the plane of maximum tensile stress. Rather, the local microscopic fracture path is on slip planes of the individual crystals that have slip planes on or near the microscopic plane of maximum shear stress, i.e. the planes at 45° angles to the direction of the load producing the stresses.
The reduction in the shear stress that causes a crack to grow can be accomplished by introducing a tensile stress acting in the direction that is at 90° to the line of the load stress. The method of the present invention provides a width direction residual tensile stress, σ w . If the magnitude of the stress, σ W , were equal to the magnitude of the longitudinal stress, the shear stress on the 45° planes on which the elements of the fracture surface lie would be zero and further crack growth could not occur. For some aluminum alloys (e.g. 2024) calculations indicate that some crack growth can actually be stopped. With the stronger alloys commonly used in aircraft structures completely stopping crack growth may not be possible; however, it is possible to reduce crack growth rates to one-tenth, or in some cases, to even one one-thousandth of the growth rate that prevailed before the width direction stress was introduced by application of the method constituting the present invention.
The method employed for producing the required width direction stress consists of heating a strategically located region or strip 18 of the sheet material to a high enough temperature to produce a temperature differential between the heated strip 18 and the sheet material surrounding the strip, which is highly restrained by the surrounding lower temperature region of the sheet, to cause the thermally expanding strip to flow plastically. The heat source 20 may be, for example, a laser. Or, a flame produced by a mixture of oxygen or air and a hyrdocarbon gas may be used. Another means of heating may include the use of a solid, constant temperature heat source in physical contact with the strip 18. The solid heat source may, for example, be copper. Since the heated strip 18 is restrained from expanding in the length direction by the adjacent colder regions and the volume has increased because of the thermal expansion, a compressive stress is generated in the heated strip.
The magnitude of the compressive stress increases with temperature differential between the hot and cold regions of the sheet. When the stress reaches the yield strength of the alloy, plastic flow occurs with an increase in temperature differential and the strip 18 of material becomes thicker (because the volume must increase with increasing temperature and the only direction free for expansion is the thickness direction). Since plastic flow produces a permanent change in sheet thickness, which tends to remain when the heated portion is cooled to the normal temperature of the entire sheet, the heated strip 18, if it were free from constraint, would be shorter at normal temperatures. However, the restraint imposed by the surrounding material forces the strip to exist at a longer dimension than it would be if the ends of the strip were free. Thus, the thickened strip 18 is forced to exist in a state with a residual tensile stress acting in the width direction.
Review of the mechanical properties of commonly used aluminum aircraft sheet materials, such as yield strength data compiled in ASM HANDBOOK VOL 2, 1979, indicated that if the surrounding lower temperature region of the sheet is at an ambient temperature (i.e., approx. 24° C.) then the temperature difference required between the heated and ambient temperature parts of the sheet would have to be so high that the 24° C. yield strength of the heated strip material would be lowered by exposure to the high temperature to an unacceptably low value. Thus, to prevent a significant loss of 24° C. yield strength, the temperature of the sheet material must be greatly lower than ambient temperature so that the desired temperature differential can be achieved without compromising yield strength.
In high strength aluminum alloy sheet material, the temperature differential between the heated strip and the neighboring material would have to be 350° C. to 400° C. to produce the magnitude of residual stress required to greatly retard the rate of growth of the fatigue crack.
However, when such aluminum alloys are heated to temperatures exceeding about 200° C. annealing reactions occur within the alloys that cause the alloy to become permanently weakened. For example, referring to FIG. 3, which is a plot of yield strength vs. temperature, it can be seen that for 7475T61 aluminum alloy, which has the highest strength of the illustrated alloys, a permanent annealing or softening effect occurs after heating to approximately 170° C. (see curve A).
Therefore, for aluminum alloys having yield strengths greater than 50,000 psi, i.e., 7000 series alloys, to provide the required temperature differential without compromising yield strength the temperature should be lowered to approximately--200° C. before the strip is heated. Liquid nitrogen, having a temperature of -196° C., is an excellent candidate for providing such a cooling of the metal sheet. This permits the maximum temperature of the heated strip to be low enough so that the 24° C. yield strength is essentially unaffected but permits the temperature differential to be adequate to create the level of residual tensile stress necessary to greatly retard the crack growth rate.
By way of example, but not limitation, the region 18 being heated may be approximately 1/8 inch by 1 inch. The region 22 being cooled by source 24, may be, for example, 1 inch by 1 inch--the heated region 18 being preferably centered within the cold region 22. The optimum width of a particular heated zone should be determined by experiments on the actual aluminum alloy sheet material that is to be treated by the process or on a very similar alloy. It depends upon the sheet thickness, the rate of heating, and other factors. Test specimens should be subjected to cooling and heating cycles with different amounts of heat input to provide the basic data needed for analytical correlations to practical applications. Such experiments being readily conductible to those skilled in the art.
The following steps provide an example of a calculation of the residual width direction stress produced in 7475 T61 aluminum alloy, assuming that the temperature of the alloy is raised from the liquid nitrogen temperature (-196° C.) to 200° C. Further calculations are provided to evaluate the significance of this residual stress:
1. Elastic strain at 200° C. yield strength: ##EQU1##
2. Thermal expansion ε EXP strain at 200° C.: ##EQU2##
3. Equate ε EXP to (ε Y200 +ε P200 ), to solve for ε P200 (where ε P200 is the plastic irreversible strain). ##EQU3##
4. Calculate σ W at 24° C. that ε P200 produces. ##EQU4##
Now that the residual width direction stress, σ W24 , has been determined, its significance may be evaluated.
The net shear stress, τ L24 -τ W24 , on the 45° plane, is equal to (σ L24 -σ W24 )/2.
This is, in the present case, equal to 14 ksi.
A decrease in crack growth rate may be determined by reference to FIG. 1 which illustrates fatigue crack growth rate vs. stress intensity range, ΔK, where ΔK is directly proportional to the shear stress (σ L /2). For example, referring to FIG. 1, when ΔK=20and we are located on a curve where fatigue growth rate da/dn=10 -6 , then if the value of ΔK is reduced by 50% to 10, then the crack growth rate on the same curve would be approximately 10 -7 . Thus, a reduction of a maximum shear stress, σ L /2, by a width direction tensile stress equal to 50% of σ L reduces the crack growth rate, da/dn, by 10 -1 . Similarly, if τ W =75% of σ L /2, the crack growth rate would be reduced by 10 -3 .
Referring now to FIG. 4, a typical line slope is illustrated which has been generated from the family of fatigue crack growth curves illustrated in FIG. 1. For the present example, i.e., βT≈400° C., the net shear stress, τ L24 -τ W24 =14, is reduced from σ L24 /2=36. Therefore, as can be seen by reference to FIG. 4, the ratio of crack growth rate with a residual width direction tensile stress to the crack growth rate without the residual width direction tensile stress is 10 -1 .7. Thus, an extremely effective method is provided to retard the crack growth rate.
The table shown below tabulates the results of calculations made for various aluminum alloys and treatment temperatures. For example, the table illustrates that if the treatment temperature for 7475T61aluminum alloy is only 177° C. instead of 200° C. then the effectiveness of the treatment is lowered from a ratio of 10 -1 .8 to 10 -1 .0. (All cases assume that the alloy is pre-cooled to the liquid nitrogen temperature.)
TABLE 1______________________________________EFFECT OF RESIDUAL WIDTH DIRECTION STRESSON THE CRACK GROWTH RATE AT 24° C.Stresses in ksi (da/dn).sub.L-W /T*°C. σ.sub.L24 σ.sub.W24 τ.sub.L24 τ.sub.W24 τ.sub.L24-W24 (da/dn).sub.L______________________________________7465 T61200 72 44 36 22 14 10.sup.-1.7177 72 33 36 16 22 10.sup.-1.07475 T761200 72 51 36 25 11 10.sup.-2.3177 72 36 36 18 18 10.sup.-1.42014 &2024 T3200 50 51 25 25 0 ZERO177 50 43 25 21 4 10.sup.-2______________________________________
where
T* is the treatment temperature;
σ L 24 is the longitudinal tensile stress at 24° C.;
σ W24 is the width direction tensile stress at 24°C.;
τ L24 is the component of shear stress on the planes at 45° due to the longitudinal tensile stress;
τ W24 is the component of shear stress on the planes at 45° due to the width direction tensile stress;
(da/dn) L is the rate of crack growth when the width direction tensile stress is zero; and
(da/dn) L-W is the rate of crack growth when the shear stress on 45° due to the width direction tensile stress is subtracted from the shear stress on those planes due to the longitudinal tensile stress (the two shear stresses act in opposite directions on the 45° planes).
For aluminum alloys having yield strengths of approximately 50 ksi or less at 24° C. and approximately 20 ksi or less at 200° C., the principles of the present invention may be effectively implemented without the need for precooling. Heating the strip from 24° C. to 200° C. without precooling still results in a significant reduction in the crack growth rate. For example, if Alloys 2014 and 2024 T3 are heated to 200° C. without any precooling the yield strength of these alloys drops to such a low value (20 ksi) that enough plastic flow occurs that a substantial residual width direction stress at 24° C. exists. The residual width direction stress is sufficiently high that the resulting crack growth rate is reduced to one-eighth of the before treatment rate. (With the full treatment, i.e., treatment including precooling to -196° C., the crack growth rate is reduced to zero.) Thus, elimination of precooling simplifies the procedure and in a number of applications is an adequate and acceptable treatment.
The principles of the present invention may be implemented in a variety of ways. The heating element should be capable of being securely anchored over the crack tip area without damaging the material to which it is attached. For example, vacuum suction cups may be used such as those that are in common use to handle large pieces of glass and large mirrors.
The device should have edge seals at the junction between the material being treated and the bottom of the equipment housing the heating and cooling devices. The seals must be able to function effectively at -196° C. so that the escape of liquid nitrogen is minimized. For example, a rubbery plastic material may be utilized that remains rubbery at such a low temperature. Or, mechanically operated curtain materials may be utilized with springs that would force sections of the curtains down against the surface of the metal being treated.
Another desired design criterion is that the device should be capable of fitting tightly on complex curved surfaces. The above-described sealing techniques allow such an implementation.
Conventional means may be utilized to supply liquid nitrogen and deliver the exhausting nitrogen gas. Temperatures of the base sheet material may be monitored by the use of contact thermocouples to assure that the desired temperature differential is achieved.
As previously noted, laser heating is preferred to assure that the strip is heated rapidly and uniformly to the desired temperature with minimum spreading of heat into adjacent cold sheet material. However, other sources of heat can also be used such as, for example, a hot jet of gas such as that obtained from a burning flame generated by a mixture of air or oxygen mixed with a hydrocarbon gas. It is desirable, but not essential, that the heat source be such that it can be oscillated from one end of the strip to the other end and that it have a width equal to the width of the strip to be heated.
A conventional optical system for remote viewing is desirable to allow fine adjustments to be made for accurately positioning the heating beam in the proper location relative to the crack tip and the crack growth direction.
Additionally, a recording system capable of monitoring and recording all of the important variables such as time, location, temperatures, operator's identification, etc., should be provided.
Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described. | A method and apparatus for reducing the fatigue crack growth rate of cracks in the aluminum alloy fuselage skin of aircraft structures. A fatigue crack is identified, the crack having a tip defining the direction of crack propagation. Temperature differentials are produced between a narrow strip of the skin and portions of the skin adjacent to this narrow strip. The narrow strip extends from the crack tip to a predetermined distance forward the crack tip. The temperature differentials produced between the narrow strip and adjacent unheated portions of the aircraft skin are sufficiently high so that the expansion due to heating causes plastic flow to occur in the heated strip. The plastic flow results in a residual tensile stress which acts in the direction of crack propagation when the system is returned to a normal service temperature. This residual tensile stress is of a sufficient magnitude to effectively retard the crack growth rate. | 2 |
This application is a continuation of application Ser. No. 07/497,715 filed Mar. 29, 1990, now abandoned, which was a division of application Ser. No. 07/370,077 filed June 23, 1989, now U.S. Pat. No. 4,931,815, issued June 5, 1990, which was a continuation of application Ser. No. 07/307,232, filed Feb. 7, 1989, now abandoned, which was a continuation of application Ser. No. 06/038,308 filed Apr. 14, 1987, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a multiple image forming apparatus for forming different images respectively on different recording members and transferring said images onto a same recording medium to obtain a multiple overlaid image.
2. Related Background Art
At first reference is made to FIG. 29 for explaining the function of a conventional color copying machine utilizing a single photosensitive drum.
In a main body 1200 of the one-drum color copying machine, there are provided a photosensitive drum 1201 rotated in a direction a, a charger 1202, a laser unit 1203, an exposure charger 1204, a surface potential sensor 1205, and color developing units 1206 for yellow, 1207 for magenta and 1208 for cyan.
The copying machines explained above functions in the following manner. The charger 1202 charges, by corona discharge, the surface of the rotating photosensitive drum 1201. A laser beam, emitted by the laser unit 1203, is projected onto the drum 1201 through mirrors. Said laser unit is provided with an unrepresented polygon mirror which is rotated to deflect the laser beam in the main scanning direction to form a main scanning line. Said laser beam is turned on and off to form an electrostatic latent image, in the form of pixels, on the surface of the photosensitive drum 1201. Subsequently the latent image is rendered visible by the deposition of color toner in one of the color developing units 1206, 1207, 1208. The obtained toner image is transferred, by means of a transfer charger 1209, onto a recording sheet 1210 supplied by a feed roller 1211 from a sheet cassette. A difference from a black-and-white copying machine lies in a fact that the sheet 1210 is supported on a support drum 1215 and rotated in a direction b. Said support drum 1215 is provided for transferring the toner images in the order of yellow, magenta and cyan onto the sheet 1210, and the peripheral speed of said drum is same as that of the photosensitive drum 1201.
After the transfer of three primary colors, the recording sheet is peeled off from the support drum 1215 and is transported to a heat fixing station 1214, and the sheet subjected to image fixation therein is discharged by a discharge roller 1213 to a copy tray 1212.
However, in terms of the copying speed, a system employing plural photosensitive drums as shown in FIG. 3 is more advantageous than the conventional structure shown in FIG. 29. Nevertheless the system with four photosensitive drums shown in FIG. 3 is still associated with problems to be solved, such as the registration of different color images, necessity for frame memories depending on the distance of the photosensitive drums, and correction for fluctuation in the sensitivity of plural photosensitive drums.
The aberration in the registration of different color images is evaluated by the observation with naked eyes, and the tolerance therefor is generally considered in the order of 100 μm.
However the control of said image registration becomes difficult if a sheet feed signal for a succeeding recording sheet is released before the start of image formation on the last photosensitive drum. For this reason the sheet feed signal for the next recording sheet is released after the start of image formation on the last photosensitive member, and high-speed printing cannot be achieved because of this fact.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a multiple image forming apparatus or a color image forming apparatus not associated with the abovementioned drawbacks of the conventional technology.
Another object of the present invention is to provide a multiple image forming apparatus or a color image forming apparatus capable of providing a sharp image without aberration in the registration of different images, by forming different images respectively in different areas, measuring the aberrations of said images and controlling the write-in timings of said images.
Still another object of the present invention is to provide a multiple image forming apparatus or a color image forming apparatus in which a common reference frequency signal is supplied to the phase locked loop control circuits of plural rotary polygon mirrors for deflecting the laser beams, in order to achieve constant revolution thereof.
Still another object of the present invention is to provide a multiple image forming apparatus or a color image forming apparatus for transferring images from plural recording members onto a recording medium in succession, wherein a new recording medium can be supplied to an upstream recording member while a downstream recording member is in the course of image transfer.
Still another object of the present invention is to provide a multiple image forming apparatus or a color image forming apparatus, provided with means for prohibiting image formation when the aberration of image registration cannot be corrected.
Still another object of the present invention is to provide a multiple image forming apparatus or a color image forming apparatus in which plural detecting members for detecting the positional aberration in the image registration are mounted on a common reference member in order to improve the precision of detection.
Still another object of the present invention is to provide a multiple image forming apparatus or a color image forming apparatus in which plural light-emitting members for detecting the positional aberration in the image registration have a constant light intensity.
The foregoing and still other objects of the present invention, and the features and advantages thereof, will become fully apparent from the following description which is to be taken in conjunction with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a digital color copying machine embodying the present invention;
FIG. 2 is a perspective view of the digital color copying machine;
FIG. 3 is a cross-sectional view of the digital color copying machine;
FIG. 4 is a perspective view of a reader unit;
FIG. 5 is a circuit diagram of a reading circuit;
FIG. 6 is a circuit diagram of a control circuit of the reader unit;
FIG. 7 is a plan view of an operation panel;
FIG. 8 is a circuit diagram of a memory circuit;
FIG. 9 is a memory map;
FIG. 10 is a circuit diagram of an APC circuit;
FIGS. 11, 12A, 12B, 12C and 13 are views and charts showing the principle of registration control;
FIG. 14 a circuit diagram showing of a positional error detecting and controlling circuit;
FIG. 15 is a perspective view showing the principle of registration control;
FIG. 16 a schematic view showing the principle of positional error;
FIG. 17 is a schematic view showing an interface between a memory unit and a printer unit;
FIG. 18 is a timing chart showing the timing of registration mark formation;
FIG. 19 is a timing chart showing the timing of HSYNC signal;
FIG. 20 is a chart showing the relation between the recording width and a BD signal;
FIGS. 21 and 22 are circuit diagrams showing a scanner motor circuit;
FIG. 23 is a circuit diagram of a phase locked loop control circuit;
FIGS. 24 and 25 are circuit diagrams of an automatic power control (APC) circuit for laser power;
FIGS. 26 and 27 are flow charts showing the control sequence of automatic laser power control;
FIG. 28 is a flow chart showing the control sequence of registration control; and
FIG. 29 is a cross-sectional view of a conventional one-drum color copying machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now the present invention will be clarified in detail by a color copying apparatus constituting an embodiment of the present invention. In the present text, the element technologies of said embodiment will be explained in the following order:
1. Outline of the apparatus
1-1. Block diagram
1-2. Structure of entire apparatus
1-3 Reader unit
1-4. Memory unit
1-5. Printer unit
2. Automatic correction of color registration
2-1. Algorism
2-2. Element technology
2-3. Timing of correction
[1. Outline of apparatus]
[1-1] Block diagram
FIG. 1 is a block diagram of the entire apparatus of the present embodiment, wherein a reader unit 100 is provided with an image reading sensor 115 and a light source 118 for illuminating the original image. An amplifier unit 103 amplifies the analog video signal from the sensor, and the obtained amplified analog video signal is supplied to an A/D converter 104. The sensor 115, composed of a CCD color sensor, releases signals of R(red), G(green) and B(blue) of a pixel in serial form. A latch circuit 105 latches said signals in the order of R, G and B, and then releases the signals R, G, B of a pixel at the same time. A color converting circuit 106 is composed of a look-up table utilizing for example a read-only memory (ROM) for obtaining signals L*, a* and b* from the signals R, G and B. In this manner the reader unit 100 releases the signals L*, a* and b*.
A memory unit 300 separately compresses the luminance signal L* and color signals a*, b*. Finally the image information of a predetermined number of pixels is compressed and stored in the frame memory or image plane memory 301. The image signals stored in the frame memory 301 are supplied, through a communication interface 320, to the outside or to a printer unit 200. In the latter case, the image signals stored in the memory 301 are decoded by an expander 304 to the original signal L*, a*, b* and supplied to the printer unit 200.
The printer unit 200 converts the image signals L*, a*, b* into image signals of C(cyan), M(magenta), Y(yellow) and K(black) corresponding to printing toners in a color conversion circuit 255 and supplies said signals in response to unsynchronized write timing signals from plural photosensitive members.
The present embodiment is provided with four laser units 201C, 201M, 201Y and 201K which respectively write the images of C, M, Y and K on photosensitive members 211C, 211M, 211Y, 211K which are formed as drums and positioned respectively corresponding to said laser units.
[1-2] Structure of entire apparatus
FIG. 2 is a perspective view of the entire digital color copying apparatus of the present embodiment, provided with the reader unit 100 for reading a color original, a memory unit 300 for storing compressed image signals, and a color printer unit 200 for forming a color image.
Also there are illustrated a sorter 21 for sorting the obtained color copies, an auto document feeder 25 for automatically feeding sheet originals, a paper deck 23 for storing and feeding a large amount of recording sheets, and sheet cassette 22A, 22B positioned in two stages.
FIG. 3 is a schematic cross-sectional view showing the internal structure of the apparatus of the present embodiment, which is abbreviated to show the basic function only, so that ancillary parts such as the sorter 21 and the paper deck 23 are omitted.
[1-3]Reader unit
Referring to FIG. 3, there are shown a light source 112 constituting an original illuminating lamp; a mirror 113; a rod lens array 114 for focusing the light reflected by an original 122 placed on a glass plate 121, onto the image reading sensor 115; a scanning member 118 supporting said original illuminating lamp 112, mirror 113, rod lens array 114, original reading sensor 115 and a circuit board 117 having an A/D conversion circuit for the image signal released by the sensor 115 through a signal line 116, and adapted to perform a linear motion in the direction indicated by an arrow integrally with said components 112-117; and a circuit board 120 having a process control circuit for storing and processing the image signal of a predetermined number of bits, 8 bits in the present embodiment, supplied from the A/D conversion circuit board 117 through a signal line 119.
FIG. 4 is a schematic view of the color image reader shown in FIG. 3, wherein same components as those in FIG. 3 are represented by same numbers. There are illustrated are a stepping motor 123 for driving the scanning member 118; a motor pulley 124 fixed on the shaft of said stepping motor 123; a belt 125 for transmitting the rotation of the motor 123 to a pulley 126 fixed on a shaft 127; a driving pulley 128 fixed on said shaft 127; two rails 129 slidably supporting the scanning member 118; a driving wire 130 which runs over the driving pulley 128 and an idler Pulley 133, biased by a spring 134 to give a tension to said wire, and is fixed on both sides of the scanning member 118 by means of a metal part 132 and a member 131; and a motor control circuit board 135 which is provided with a motor driver circuit for generating a signal for driving the stepping motor 123 in response to signals supplied from the process control circuit 120 through a signal line 136 and a pulse generating circuit for generating timing pulses for said drive signal and which is connected to the stepping motor 123 through a signal line 137.
The above-explained structure converts the rotation of the stepping motor 123, through the motor pulley 124, belt 125, pulley 126, shaft 127, driving pulley 128, wire 130, metal part 132 and member 131, into a linear movement of the scanning member 118 on the rails 129, and the direction of said linear movement is controlled by the forward or reverse rotation of said stepping motor 123.
The original image is read by the scanning motion, at a constant speed, of the image reading unit consisting of the lamp 112, mirror 113, rod lens array 114, image reading sensor 115 etc. moving integrally with the scanning member 118. The actual image reading operation is conducted from the front end position of the original image.
FIG. 5 is a block diagram of the reader unit. The image reading system will not be explained in detail as it is same as described before. On an original document 122, the main scanning direction and the sub scanning direction are respectively represented by MS and SS. The rod lens array 114 is simply illustrated as a lens.
The image signals from the sensor 115 are supplied to the aforementioned A/D conversion circuit board 117. The analog signals of B, G and R are serially entered, amplified in a preamplifier 701, and supplied to sample hold circuits 703. Timing pulses φ B , φ G , φ R are used for causing the sample holdings of the serial analog signals of B, G, R, and a pulse generator 702 is provided for generating said timing pulses, including sample hold pulses for the CCD sensor.
The amplifiers 103 are provided with gain controllers 103' for mutually balancing the signals B, G, R. A/D converters 104 are provided for converting the analog signals of B, G, R respectively into digital signals of 8 bits each.
FIG. 6 is a block diagram of a control circuit for controlling the reader unit. 1150 indicates a CPU composed for example of a microcomputer. A driving unit 1151 for activating various components of the reader unit corresponds for example to the aforementioned stepping motor 123. 1152 indicates a power switch of the printer unit. In case of sheet jamming in the printer unit, the power supply to the printer unit may be cut off during an operation to remove the jammed sheet. A keyboard 1153 is provided for data entry with the input keys shown in FIG. 7. A display unit 1154 turns on "no toner" lamps under the control of the CPU 1150 in response to signals 1156 for activating the copy number indicator 1103 shown in FIG. 7 or indicating the absence of toners of cyan, magenta, yellow and black. More specifically the operation panel shown in FIG. 7 is provided with four "no toner" lamps 1101 respectively indicating the absence of C(cyan), M (magenta), Y(yellow) or K(black) toner.
When any of said lamps is turned on, indicating the absence of corresponding toner, the color copying function is disabled, so that the normal copying operation cannot be started with the normal copy key 1107. However, for any other color, the copying operation can be started with a single-color copy key 1113. Naturally such single-color-copying is disabled when all four "no toner" lamps are turned on.
Referring to FIG. 7, there are shown numeral keys 1106 for entering copy number etc.; a clear key 1108 for clearing the number entered by the numeral keys; a number indicator 1103 for indicating the copy number etc.; a jam indicator 1102; a wait indicator 1105; a stop key 1120 for interrupting the copying operation etc.; upper and lower cassette selecting keys 1110, 1111 for respectively selecting the upper cassette 22A or the lower cassette 22B shown in FIG. 2; a paper deck selecting key 1121 for selecting the paper deck 23 shown in FIG. 2; a density lever 1112 for regulating the density of the color copy, by controlling the luminance signal L* in the present embodiment; and a memory clear key 1122 for forcedly erasing the image signals remaining in the image frame memory, particularly in case the copying operation is not re-started after sheet jamming.
In response to the actuation of said memory clear key 1122, the CPU 1150 sends a memory clear signal 1155 shown in FIG. 6 to the memory unit 300, thereby erasing the content thereof.
A color saturation knob 1123 regulates the color saturation by controlling the color signals a*, b*. An APC ready signal 1157 indicates the completion of a potential control to be explained later and a subsequent automatic power control on the laser output.
An auto registration ready signal 1158 indicates the completion of an automatic registration to be explained later. These signals have to be received before a copying operation is conducted. The copying operation is enabled and the wait indicator 1105 is turned off when other conditions which are required also in the ordinary copying machine, such as the temperature control of the fixing heater, presence of recording sheets, and the presence of all toners indicated by the signals 1156.
[1-4] Memory unit
The memory unit is used for storing the image signals between the reader unit and the printer unit. An image frame requires a memory capacity of 16 MBytes in case an image of A4 (210×297 mm) size is read with a resolving power of 16 pixels/mm in both scanning directions and with a gradation of 8 bits/pixel. The memory capacity becomes as large as 16×3 =48 MB if this is expanded to three colors R, G and B, or 16×4 =64 MB if this is expanded to four colors Y, M, C and K. Such capacities will require 384 (48 MB) or 512 (64 MB) DRAM's of 1Mbit, or a quarter of these figures even when 4Mbit DRAMS's are employed.
Also usual copying apparatus is required to handle sizes up to A3 size, so that the number of required memories will have to be doubled.
For this reason the present embodiment employs data compression in order to reduce the required memory capacity, thereby decreasing the number of memory chips, and to reduce the data processing time including data transmission. With a compression rate of 1/12, the memory capacity is reduced to 48 MB ÷12 =8 MB, which can be practically covered with 64 1M DRAM's. Also the data bit width is increased to 32 bits to enable high-speed access.
FIG. 8 shows the structure of memory in the present embodiment, employing 1Mbit memory chips 1-64, which are divided into a former half 1-32 and a latter half 33-64 for enabling 32 bit parallel entry. Since the entire memory capacity is 8 MB as explained above, there will be required 21 address lines for enabling 32 bit parallel access.
In FIG. 8, an address counter 801 generates said 21 addresses, of which lower 20 digits (A0-said A19) are supplied to each 1Mbit DRAM requiring 20 addresses. These are shown as an address bus 804 (A0-A19). 1 Mbit DRAM usually have a bit structure of 1 bit ×1048576, and 20 addresses are usually divided RAS and CAS or upper 10 bits and lower 10 bits, but the detailed explanation will be omitted. Also the refreshing operation required for maintaining the content of DRAM will not be explained.
As explained above, 64 memory chips are divided into two groups, either of which is selected by a chip select signal CS, supplied through an address bus A20, shown by 805 in FIG. 8, according to the logic state of an inverter 806.
More specifically, the memory chips of the former half are selected by said signal CS when the address 805 of the uppermost digit is "0".
FIG. 9 shows the memory map of 8 MB, containing 1995840 blocks of 32 bits each, therefore requiring 1E7440(hex) addresses. These addresses are generated by an address counter 101 in synchronization with a reading clock fl or a writing clock f2 either of which is selected by a signal 802.
A read/write select signal R/W selects the writing mode at "0" or the reading mode at "1". Each memory chip has a data input port Din and a data output port Dout, and the ports Din or Dout of the corresponding memory chips in the former half group and in the latter half group are mutually connected. The mutual connection of the output ports poses no problem because the output port Dout in particular is of a high impedance when it is not selected (CS="1").
The total memory capacity for A3 size was explained as 8 MB in the foregoing, the address in fact proceeds only to 1E7440 (Hex) because the area of A3 size (297×420 mm) expressed in binary number is different from 8MB. In fact the memory capacity in this case has a surplus of 101312 blocks, corresponding to an image area of ca. 21 mm×297 mm.
In FIG. 8, the memory clear signal 1155 is used for clearing the content of all the memory chips as explained before, and is supplied to the clear terminal CLR of each memory chip.
[1-5] Printer unit
As shown in FIG. 3, the four-drum color printer 200 has four units, each having a photosensitive drum, and containing toners of different colors in color developing units 205.
Also in FIG. 3 there are provided laser units 201C, 201M, 201Y and 201K respectively for color signals of cyan (C), magenta (M), yellow (Y) and black (K). Each unit has an unrepresented rotating polygon mirror to deflect the laser beam in the main scanning direction, thereby forming the main scanning line.
In each of the identically constructed units, the photosensitive drum 211 is rotated clockwise and surfacially changed with a charger 212.
The laser beam is turned on and off to record the pixel information in the form of a latent image, which is rendered visible by the deposition of color toner with a developing sleeve 206. The obtained toner image is transferred, by a transfer charger 210, to a recording sheet supplied from a cassette 208 through a feed roller 207. The front end position of the sheet is adjusted by registration roller 250.
The recording sheet is transported, by a conveyor belt 209, from the cyan color development to the next color unit of magenta. Subsequently yellow and black toner images are overlaid in succession, and the sheet is transported to a fixing station 213 when the toner images of four colors are overlaid, and the images are fixed with heating rollers 216. Then the sheet is discharged to a tray 215 by discharge rollers 216.
In the one-drum color copying apparatus shown in FIG. 29, the deterioration of image quality caused by the sensitivity loss of the photosensitive member affects all the colors in the same manner. Consequently the color balance remains relatively balanced even in case of such deterioration. Consequently the deterioration of image quality can be prevented by a simple surface potential control.
On the other hand, in the four-drum color copying apparatus, four drums undergo independent changes in sensitivity. Also the color balance is affected for example by the replacement of one of photosensitive drums with a new one. These drawbacks are resolved by the present embodiment.
FIG. 10 is a magnified view of the photosensitive drum 211 and the associated structure of a unit. There is provided a potential sensor 1008 for measuring the surface potential of the photosensitive drum 211.
The photosensitive drum is charged to a surface potential V0 by the corona discharge with the charger 212, but undergoes a dark decay to an exposure position A where the exposure with laser beam is conducted, as shown in FIG. 10. The surface potential is changed by the amount of exposure, or the level of the laser power. In case of analog recording, the image density can be regulated by the intensity of the laser beam, but such density regulation is not required in the digital recording of the present embodiment.
As shown in FIG. 10, a high voltage transformer 230 is provided, in order to maintain a predetermined laser power and a constant beam diameter for irradiating the photosensitive drum 211. The sensitivity of the drum is identified by measuring the surface potential thereof in this state.
The surface potential measured with said sensor after exposure with a predetermined laser power is assumed as V L0 . This is the target value, and the actual value V L1 is higher, thus reducing the dynamic range, due to the deterioration of the photosensitive drum 211 or an insufficient exposure cause by the deterioration of the laser power. In either case, the problem can be resolved by the increase of the laser power. The control of the potential control will be explained in the item [2-3].
FIG. 11 illustrates the timings of starting the image recordings.
The front end of the recording sheet 208 advanced by the registration roller 250 as explained before reaches the photosensitive drum 211C, 211M, 11Y or 211K respectively at a time T1, T2, T3 or T4 from the feed timing T0 to start the transfer of the toner image.
FIG. 12A is a timing chart showing the proceeding of said image transfers.
In response to an output signal RR from the CPU 505 shown in FIG. 12C, the registration rollers 250 starts rotation from a time T0, and said signal RR is continued for a period required by the sheet to pass through said rollers, depending on the size of the sheet. The image transfer from each photosensitive drum is started with a delay T1, T2, T3 or T4. Thus the recording on each photosensitive drum is started with a delay t 1 =T 1 -τ, t 2 =T 2 -τ, t 3 =T 3 -τ or t 4 =T 4 -τ, wherein τis the time required by each photosensitive drum to reach the image transfer position from the laser recording position, and the image recording is conducted for a duration same as the driving time of the registration roller 250.
FIG. 12B shows the timings of image signal recording on plural photosensitive drums in case of consecutively obtaining three copies. For the photosensitive drums 211C and 211M, the write timing signals SYNC1, SYNC2 are by counting t1, t2 respectively with counters CNT10, CNT 20 in the same sequence as shown in FIG. 12A.
However, for the photosensitive drums 211Y and 211K, a next recording sheet is already advanced before the time t3 or t4 expires for the first recording sheet. For this reason counters CNT 32, CNT 42 for measuring the times t3, t4 are additionally provided, and the counters CNT31 and CNT 32, or CNT 41 and CNT 42 are alternately used to obtain the write timing signal SYNC3 or SYNC4 for the second or third sheet.
FIG. 12C shows a circuit for obtaining the write timing signals SYNC1-SYNC4.
The above-explained counters CNT10, CNT20, CNT 31, CNT 32, CNT41, CNT42 perform time measuring operation by counting clock pulses CLK from a clock generator 510. There are provided a driver circuit 500 for a motor 25M for rotating the registration rollers 250, to be activated by the registration roller signal RR; toggle circuits 501, 502 for activating the counter CNT 31 or CNT 32 according to the number of the registration roller signals RR; OR circuits 503, 504 for releasing an output signal in case the counter CNT31 or CNT32 has completed the counting operation to set a JK flip-flop 508 for generating the write signal SYNC3; and flip-flops 506-509 each set by the completion of the counting operation and reset by a reset signal RS from the CPU 505. The duration of setting is calculated according to the size of the recording sheet, and coincides with the rotating period of the registration rollers 250 shown in FIG. 12A, or the duration of the signal RR.
The photosensitive drum 211C or 211M requires only one counter, but the photosensitive drum 211Y or 211K in the present embodiment uses two counters. The number of counters is determined by the sheet size and the distance between the photosensitive drums, but in general the drum at the upstream side requires fewer counters.
In the present embodiment the counting operation of each counter is started by the registration signal RR, but it may also be started by detecting means for the recording sheet positioned upstream of the image transfer position of the first photosensitive drum. Also the counter utilized as the time measuring means may be replaced by a timer composed of capacitors and resistors.
Because of the above-explained difficulties specific to the four-drum printer, the access to the image frame memory is modified accordingly.
FIG. 13 shows the timing of data storage into the memory by the movement of the optical system in the reader unit and the timing of image recording by the activation of the registration rollers in the printer unit and by the laser units thereof.
In FIG. 13, (1) indicates the timing of image reading by the movement of the optical system 118 shown in FIG. 3, while (2), (3) and (4) indicate image signals R, G, B of the A/D conversion circuit board 117 shown in FIG. 5. Said image signals are supplied to the memory unit 300, in synchronization with memory write clock signal f WR (10), for color conversion, data compression and storage. The image signals stored in the memory are then supplied to the printer unit.
Since four photosensitive drums are in different positions, the image signals C, M, Y and K have to be independently obtained in a synchronous manner.
In FIG. 13 these signals are represented by (6), (7), (8) and (9), and (11), (12), (13) and (14) are respectively corresponding read-out clock signals f RD .
These operations can be achieved by high-speed switching in the color conversion circuit 250 of the printer unit 200 shown in FIG. 1.
In the memory unit, as shown in FIG. 8, the memory write clock signal f WR (850) and the memory read clock signal f RD (851) are supplied to a multiplexer 802, switched according to the timing of data writing and reading, and supplied to an address counter 801 which accordingly generates addresses for the memory chips. The address in this case is not increased in the unit of pixel but in the unit of a block of 4×4 pixels.
[2]Automatic correction of color registration
In a four-drum digital color copying apparatus such as in the present embodiment, the formation of an image with proper color through correction of color registration is naturally one of basic requirements. For this reason, the apparatus of the present embodiment is provided with means for automatic correction of color registration.
[2-1] Correcting means
A sharp color image without error in the color registration can be obtained in the laser beam printer, by forming unfixed registration markers on the conveyor belt with the usual image forming means, then measuring the errors in the color registration and accordingly controlling the timing of image recording.
More specifically there are provided image formation control means for forming, respectively in plural areas of a recording medium divided in the main scanning direction, predetermined images formed on respective photosensitive drums; registration error measuring means for measuring the relative positional errors of the images formed in said areas by said image formation control means; and registration error correcting means for correcting the timing of image recording with the laser beam on each photosensitive drum, according to the error measured by said measuring means.
FIG. 14 is a block diagram of a positional error correcting circuit, wherein a CPU 1401 causes the formation of predetermined images respectively in areas of a transported recording medium divided in the main scanning direction, and calculates the registration errors of said images from the outputs of positional error detectors 1402C, 1402M, 1402Y and 1402K composed for example of CCD's. There are provided counters 1403a-1403d. The counter 1403a counts the time from the start of a recording sheet from the registration rollers to the start of cyan image recording. The counter 1403b counts the timing of starting the image recording, including the positional error of the magenta image with respect to the cyan image calculated by the CPU 1401. Similarly the counter 1403c counts the positional error of the yellow image with respect to the cyan image, calculated by the CPU 1401, and the counter 1403d counts the positional error of the black image with respect to the cyan image, calculated by the CPU 1401.
When the counters 1403a-1403d complete the counting operations, they release carry signals to set JK flip-flops 1405a-1405d thereby shifting write enable signals VDOa-VDOd to the H-level. Thus AND gates 1404a-1404d are opened to release the aforementioned beam detection signals BD-C-BD-K, which constitute horizontal synchronization signals HSYNC for controlling the synchronization of the laser beam in the main scanning direction. Said signals HSYNC are supplied to the image memory.
FIG. 15 is a perspective view showing the principle of positional error detection in the present embodiment. The recording medium 1505 is constituted by the conveyor belt in the present embodiment. Latent images formed by the laser units 201C, 201M, 201Y, 201K on the photosensitive drums 211C, 211M, 211Y, 211K are developed to obtain predetermined images 1501C, 1501M, 1501Y, 1501K. A sensor circuit board 1506 is provided with positional error detectors 1402C, 1402M, 1402Y, 1402K in predetermined positions. It is assumed that the photosensitive drums 211C, 211M, 211Y, 211K are positioned with a given distance L, and that the image formation starts at a time t1, t2, t3 or t4 from the start of sheet feeding from the registration rollers 250, respectively on the photosensitive drum 211C, 211M, 211Y or 211K, as shown in FIG. 18. As shown in FIG. 18, the registration rollers 250 are maintained in rotation, after having started to feed the recording sheet, for a period t0 necessary for the sheet of A4 size to pass through said registration rollers 250. The image write enable signals VDO-C, VDO-M, VDO-Y and VDO-K enable the image storage respectively after times t1, t2, t3 and t4 from the start of feeding of the recording sheet by the rotation of the registration rollers 250. The timings remain unchanged even when the recording sheet is not fed as in the present case.
Now reference is made to FIG. 19 for more detailed explanation. In FIG. 19, the beam detection signal BD from the beam detector 1513 is released during the rotation of the polygon mirror.
As already explained before, upon completion of the counting operations of the counters 1403a-1403d, the JK flip-flops 1405a-1405d are set through J terminals thereof to release H-level output signals. The beam detection signal BD is extracted by the AND agtes 1404a-1404d only during the image formation to provide HSYNC signals. The image formation is conducted by reading the image signals from the memory 300 in synchronization with said signals HSYNC as shown in FIG. 17.
In FIG. 17, the signals HSYNC-C, HSYNC-M, HSYNC-Y and HSYNC-K made access to the memory unit 300 to supply the image signals C, M, Y and K to the laser units 201C, 201M, 201Y and 201K.
A color converter 255 converts the luminance signal L* and color signals a*, b* into the signals C, M, Y and K, as shown in FIG. 1.
FIG. 16 is a plan view of the sensor circuit board 1506 shown in FIG. 15, wherein same components as those in FIG. 15 are represented by same numbers.
The aforementioned recording medium 1505 has areas 1600C, 1600M, 1600Y, 1600K of different colors divided in the main scanning direction. In the illustrated case, with respect to the image 1501C formed on the area 1600C, the images 1501M, 1501Y, 1501K respectively formed in the areas 1600M, 1600Y, 1600K have positional errors of Δy2, Δy3 and Δy4. A reference plate 1602 eliminates the errors in the mounting of the error detectors 1402C, 1402M, 1402Y and 1402K. An arrow 1604 indicates the moving direction of the recording medium 1505 or the sub scanning direction.
After the formation of the predetermined images 1501C-1501K in the areas 1600C-1600K of the transported recording medium 1505 by means of the photosensitive drums 211C-211K mutually distanced by L, namely after the lapse of time t4, said images are transported to the position of the sensor circuit board 1506. Thus the images 1501C-1501K in said areas 1600C-1600K are detected by the positional error sensors 1402C-1402K. In this operation, the relative positional errors Δy2, Δy3, Δy4 of the images 1501M-1501K with reference to the image 1501C, and the corresponding times are added to the aforementioned periods t2, t3, t4 and the obtained values (t2 +Δ|y2|), (t3-|Δy3|) and (t4 +|Δy4|) are respectively set in the counters 1303b-1303d. Thus, in the image formation. Thus, after the lapse of the corrected periods determined by the completion of the counting operation of the counters 1403b-1403d, the enable signals VDO-C, VDO-M, VDO-Y, VDO-K are released to the laser units 201M, 201Y, 201K.
In this manner the errors in color registration can be automatically corrected.
As explained in the foregoing, a marker reading method is proposed for automatically correcting the errors in the color registration. This method is naturally based on stable formation of markers, and said stable formation requires that:
(i) the revolution of four polygon mirrors is exactly same; and
(ii) the four photosensitive drums have almost same sensitivity so that the markers do not show significant difference in density.
The first requirement is achieved by employing a common oscillator, for example a crystal oscillator, for the control circuits of plural polygon mirrors. Also the second requirement is achieved through the control of the surface potential.
In the present embodiment means for resolving these requirements constitute important technical components of automatic correction of color registration, as will be explained in the following. As shown in FIG. 16, the widths Y1-Y4 of the markers 1501C-1501K are proportional to the number of main scanning lines and are represented by the product of a time t1=N×t BD and the process speed. Said widths Y1-Y4 are formed by the laser beam irradiations from four polygon mirrors. Consequently the fluctuation in the time t BD naturally affects said widths Y1-Y4. Also the precision of marker detection can be improved by maintaining a constant density of the markers through the control of surface potential.
[2-2] Use of common reference oscillator
In the following there will be given further explanation on the laser units 201C, 201M, 201Y, 201K shown in FIGS. 1, 3 and 15. The following description will however be concentrated on the laser unit 201C and other units will not be explained.
In FIG. 15, the laser beam emitted by a semiconductor laser 1005 is reflected by a polygon mirror 1510 and uniformly scans the photosensitive drum 211C through an f-θ lens 1511, in a direction indicated by an arrow. A mirror 1512 receives the laser beam from the laser unit 201C in front of the start position of image recording and guides said beam to a beam detection signal generating unit 1513 to generate the signal BD-C. Such structure is same for other laser units.
FIGS. 21 and 22 are block diagrams showing a control circuit for a scanner motor 1514 shown in FIG. 19.
A driver circuit 61 is provided with a rotor 61a, composed for example of a permanent magnet, for rotating the polygon mirror 1510. Said rotor 61a is provided with Hall devices 62a, 62b placed at a predetermined angular position of the rotor 61a, for example at 135°. Stators 63a-63d are provided with coils in such a manner that the stators 63a, 63d facing the rotor 61a constitute S poles when the coils of said stators are energized and that the stators 63b, 63c facing the rotor 61a constitute N poles when the coils of said stators are energized. A Hall IC 64 is positioned close to the rotor 61a for feeding a detected frequency signal FG to a control unit 65, which is provided with a PLL control circuit 65a, a current amplifier 65b and a current limiter 65c for controlling the current supplied to the stators 63a-63d based on said frequency signal FG and a drive signal M supplied from an unrepresented CPU. Hall devices 62a, 62b generate a voltage "0" and "1" respectively at the "-" terminal and "+" terminal when an N pole of the rotor 61a approaches, and a voltage "1" and "0" respectively when an S pole approaches.
In a position shown in FIG. 21 where the Hall device 62a faces an N pole, the output Ha becomes "0" to supply a current to the stator 63a. Thus the stator 63a is magnetized as an S pole, which repels the S pole of the rotor 61a and attracts the N pole thereof, thus generating a rotating force in the illustrated direction. As the N pole positioned on the Hall device 62a moves away by the rotation of the rotor 61a, the Hall device 62a loses the electromotive force so that the stator 63a becomes cut off. On the other hand, an S pole of the rotor 61a approaches to the Hall device 62b to shift the output Hb to "0", whereby the stator 63b is energized and magnetized as an N pole which attracts said S pole. In this manner the outputs Ha, Hb, Hc and Hd are shifted to "0" in succession to correspondingly magnetize the stator 63a-63d, thus maintaining the rotation of the rotor 61a.
The rotating speed is detected by the Hall IC 64 positioned close to the rotor 61a, and the detected frequency signal FG is supplied to a revolution control circuit 65 to control the currents to the stators 63a-63d so as to maintain a constant revolution of the rotor 61a. Such rotor 61a is naturally provided for each polygon mirror 1510.
In FIG. 22, a PLL IC 71 (PLL control means) composed for example of a device HA12032 (Hitachi) controls the current supplied to the stators 63a-63d by comparing the frequency signal FG from the Hall IC 64 with a reference frequency signal FV supplied from a reference frequency oscillator 72 composed of a crystal oscillator. Such PLL IC chip 71 is provided for each scanner motor 1514.
In this manner the PLL IC 71 controls the revolution of each scanner motor 1514 in synchronization with the reference frequency signal FV supplied from a corresponding reference frequency oscillator 72, so that the revolutions of the scanner motors 1514 cannot be maintained identical due to the fluctuation of the reference frequency signals FV. Thus the markers have different Y1-Y4 and are suitable for correcting the errors in the image registration. This drawback can however be resolved by employing a common oscillator for supplying the reference frequency signal to different PLL IC's, and automatic correction of the color registration can be achieved by the use of common means for supplying a common reference frequency signal to plural PLL control means.
FIG. 23 is a circuit diagram of a PLL control circuit for a laser beam printer, employing a common oscillator, wherein same components as those in FIG. 22 are represented by same numbers. Common frequency signal generator 2300 supplies a common reference frequency signal f0 to an input terminal X of the PLL IC 71 of each color.
Each PLL IC 71 controls the revolution of each scanner motor 1514, by comparing the frequency signal FG fed back from each Hall IC with said reference frequency signal f0.
Consequently the PLL IC's 71 provide an identical revolution, thus avoiding the difference in the widths Y1-Y4 of the registration correcting markers.
[2-3] Surface potential control
The form of the registration correcting markers is very important, because the measurement of the error in registration relies on the detection of the edges of the marker. For this purpose the density of the marker has to be maintained constant, and this can be achieved through the surface potential control of the photosensitive drum.
Again referring to FIG. 10, the photo sensitive drum 211, rotated in a direction of arrow, is uniformly charged, with corona discharge, by the primary charger 212 powered by the high-voltage transformer 230. An auto power controller 1004, constituting current control means and current correcting means of the present invention, releases drive current data, for example in the form of 8 bits, for supplying a reference drive current to a laser circuit board 1005 provided with a laser driver circuit 1005a, a D/A converter 1005b and a semiconductor laser 1005c. A power detector 1006, constituting the monitor means of the present invention, detects the light emitting power of the semiconductor laser 1005c of said board 1005, amplifies the obtained power with an amplifier 1006a and supplies the power data through an A/D converter 1006b to a CPU 1004a of the auto power controller (APC) 1004. A laser beam 1007 is projected, from the laser circuit board 1005, onto the exposure point A of the photosensitive drum 211. A potential sensor 1008 measures, at a measuring point B, of the surface potential of said photosensitive drum 211 subjected to the irradiation with the laser beam 1007 at the exposure point A. A potential measuring unit 1009, constituting the potential measuring means of the present invention, converts the output of the potential sensor 1008 into a digital value by an A/D converter 1009a and sends said value to the CPU 1004a of the APC 1004. The developing sleeve 206 receives replenishment of toner by replenishing rollers R1, R2. The conveyor belt 209 is moved in a direction indicated by an arrow, and the registration correcting marker developed on the photosensitive drum 211 is transferred onto said belt 209 by means of the transfer charger 210.
FIG. 24 is a block diagram of a circuit for surface potential control and auto power control, wherein same components as those in FIG. 10 are represented by same numbers. In the following there will be explained the circuit functions for surface potential control and auto power control with reference to FIGS. 24 and 25, while the control sequence of this circuit will be more detailedly explained later in reference to a flow chart.
At first, FIG. 24 shows a series of control systems consisting of the potential sensor 1008, A/D converter 1009a, microcomputer 1009b, CPU 1004a of the APC, D/A converter 1005b, laser driver circuit 1005a, semiconductor laser 1005c, photodiode 1006c, amplifier 1006a, A/D converter 1006b and CPU 1004a of the APC. The objective of the auto power control function is to maintain the surface potential of the photosensitive drum at a constant level. This objective is achieved by storing the value measured with the surface potential sensor, and maintaining the light intensity required at this point. In the present embodiment, it is desirable to have centralized control over four photosensitive drums. As shown in FIG. 25, the APC 1004 is connected to four potential measuring units 1009, four laser circuit boards 1005 with respective semiconductor lasers 1005c, and four power detectors 1006 with respective photodiodes 1006c. Consequently the CPU 1004a of the APC can hold all the status relating to the latent image formation.
FIG. 26 is a flow chart showing an example of surface potential measurement, consisting of steps (1) to (11).
At first the photosensitive drum 211 is charged to a surface potential V D by the primary charger 212. When it reaches the exposure point A, the APC 1004 sends the reference drive current data to the D/A converter 1005b of the laser circuit board 1005 thereby supplying the semiconductor laser 1005c with the reference drive current IO and projecting the laser beam 1007 onto the photosensitive drum 211 (1). Then a discrimination is made as to whether the number N of adjustment has reached a predetermined number a (2), and, if said number is reached, an error flag is set and the control procedure is terminated (3). If not reached, the program awaits that the photosensitive drum 211 reaches the potential measuring point B (4), and the surface potential is detected by the potential sensor 1008 when said point is reached (5). The output of said sensor 1008 is converted by the A/D converter 1009a of the potential measuring unit 1009, and further converted into table data by the microcomputer 1009b. Then a discrimination is made as to whether the measured potential coincides with the desired potential V L (6), and, if the result is affirmative, the supplied laser drive current (reference drive current IO+Δα) is stored in an unrepresented memory and the control procedure is terminated (7).
On the other hand, if the discrimination in the step (6) is negative, the number N of measurements is increased by one (8). Then a discrimination is made as to whether the measured potential is higher than the desired potential V L (9), and, if the result is affirmative, the laser drive current is adjusted to (reference drive current IO+ΔIO) to increase the laser power (10) and the program returns to the step (2). If the result is negative, the laser drive current is adjusted to (reference drive current IO -ΔIO) to decrease the laser power (11) and the program returns to the step (2). ΔIO is the minimum increase or decrease of the current in a control step, and corresponds to a change in the least significant bit (LSB) of the D/A converter 1005b. Δα is equal to ΔIO times the number N of adjustments.
In this manner a laser power P0 corresponding to the surface potential V L of the photosensitive drum can be generated by a laser drive current (reference drive current IO-Δα).
Consequently a constant surface potential of the photosensitive drum 211 can be obtained by a constant laser power P0. However the semiconductor laser 1005c of the laser circuit board 1005 is easily influenced by circumferential conditions such as temperature, and the relation between the laser power and the laser drive current is not constant. Therefore, in order to obtain a constant laser power P0, the laser drive current (reference drive current IO -Δα) should additionally contain a correction Δβ for the change in such ambient conditions. For this purpose the power of the semiconductor laser 1005c is constantly monitored by the power detector 1006c, and the change in power is supplied, through the A/D converter 1006b, to the CPU 1004a of the APC 1004.
Now reference is made to FIG. 25 for explaining the monitored control of the laser power.
FIG. 27 is a flow chart showing an example of the monitored control laser power, consisting of steps (1) to (8).
At first the image formation is conducted with a laser drive current providing a laser power P0 which gives a surface potential V L on the photosensitive drum 211 (1). Then the program awaits a non-image area between the recording sheets, or a period for measuring the laser power defined at a predetermined interval (2), and the power of the semiconductor laser 1005c of the laser circuit board 1005 is monitored with the power detector 1006c, amplified by the amplifier 1006a and supplied through the A/D converter 1006b, as power data PD, to the CPU 1004a of the APC 1004 (3). Then there is discriminated whether the power data PD coincides with the initial laser power P0 (4), and, if affirmative, a laser drive current (reference drive current IO+Δα+Δβ) is supplied to the laser driver circuit 1005a, and the control procedure is terminated by setting an APC ready signal 1157 (5).
On the other hand, if the discrimination in the step (4) turns out negative, there is discriminated whether the power data PD is larger than the initial laser power P0 (6), and, if larger, a laser drive current (reference drive current IO+-ΔIO) is supplied to the laser driver circuit 1005a in order to reduce the laser power (7) and the program returns to the step (2). On the other hand, if smaller, a laser drive current (reference drive current IO+Δα+ΔIO) is supplied to the laser driver circuit 1005a in order to increase the laser power (8) and the program returns to the step (2). ΔIO is the minimum increase or decrease of the current in a control step, and corresponds to a change in the least significant bit (LSB) of the D/A converter 1005b. Δβ is equal to ΔIO times the number N of adjustments.
The positional error detector 1402, composed for example of a CCD sensor, requires a light source with a stable light intensity, since a fluctuation in the light intensity results in an error in the edge position of the marker when the marker 1501 is illuminated by said light source and is detected by the sensor.
In FIG. 14, the light sources 1603, composed of light-emitting diodes, are respectively associated with constant current circuits 1406 for stabilizing the light intensity. In case the S/N ratio of the registration correcting markers 1501 is insufficient due to the stain on the conveyor belt 209 on which said markers are formed, the light intensities of the light-emitting elements 1603C, 1603M, 1603Y, 1603K have to be increased in mutually balanced state. For this reason a constant voltage circuit 1409 is provided with a variable resistor 1407 for varying the output voltage V0. A power source 1408 is provided for driving said light-emitting elements 1603.
The reading precision of the registration correcting markers 1501 is very important, since the control of color registration is not possible if the reading precision is lower than the resolving power of the color copy. Said reading precision is naturally influenced significantly by the precision of formation of the above-mentioned registration correcting markers 1501, the resolving power of the reading sensors 1402, and the stability or time-dependent change of the relative mounting precision of four CCD sensors. Therefore, this problem can be resolved if four CCD sensors are integrally fixed. A right-hand view in FIG. 16 is a cross-sectional view of the sensor board 1506, wherein shown are a casing 1606; a lamp 1605 for illuminating the registration correcting markers 1501; a CCD sensor 1404; a printed circuit board 1608 for mounting said CCD sensor; and a short-focus lens array 1606. This structure allows to exactly read the markers 1501, thereby improving the precision of the correction.
The CCD sensors 1402 and the illuminating lamp 1605 are influenced by the temperature and humidity over a long time, and such influence can be best compensated by a standard reflecting board 1602, shown in FIG. 16, of for example white color. Such board enables compensation by reading the reference light without substantial influence of the spectral sensitivity of the CCD sensors.
[2-4] Timing correction
Now reference is made to FIGS. 14 and 16 for explaining the timing correction for automatic color registration in the present embodiment.
FIG. 28 is a flow chart showing the sequence of correcting the timing of image formation of the present invention, consisting of steps (10 to 12).
Referring to FIG. 14, the CPU 1401 sets initial values in the counters 1403a-1403d, in order to start the formation of the correcting markers 1501C-1501K on the conveyor belt 1505 after the lapse of respective initial values t1-t4. This corresponds to a step (1) in FIG. 28.
As already explained before, FIG. 16 shows a state in which all the correcting markers are formed. The belt 1505 serves as the conveyor belt and is formed as an endless belt, and the correcting markers are formed on said belt. Thus relative errors in color registration have to be determined as differences from a certain reference time. In the present embodiment said reference time is defined by the front end of an imaginary recording sheet. The program awaits the detection of the front end of the imaginary sheet on the belt 1505 shown in FIG. 16 by any of the detectors 1402C-1402K (2), and, upon said detection, an unrepresented timer circuit measures the time Δx1, Δx2, Δx3 and Δx4 to the detection of the markers 1501C-1501K and stores said time in an internal memory (steps (3)-(6)). Then the relative differences from Δx1 are determined as Δy2 =Δx1-Ax2, Δy3=Δx1-Δx3 and Δy4=Δx1-Δx4 (steps (7) to (9)). Then thus obtained time differences Δy2, Δy3 and Δy4 and the times t2, t3 and t4 are used for calculating corrected times t2 +Δy2, t3 +Δy3 and t4+Δy4, which are set in the counters 1403a-1403d (steps (10) to (12)). Then there is checked whether the values set in the counters 1403a-1403d are within the correctable range (13). If said values are within said range, the automatic registration signal 1158 is set as the automatic correction is possible (14). On the other hand, if said values are not in said range, said signal is reset.
In the illustrated case, the correcting marker for the cyan image is detected at first, and is used for calculating the differences, but any other marker that is detected at first may naturally be used as reference in the same manner.
The foregoing embodiment is limited to a color printer provided with plural electrophotographic photosensitive drums, but the present invention is also applicable to other printers, such as a thermal transfer printer in which a multiple image is formed by forming different images respectively on different recording materials and transferring said images onto a same recording medium.
As detailedly explained in the foregoing, the present invention allows to obtain a multiple image without error in image registration or a color image without error in color registration. Also it enables high-speed formation a color or multiple image.
The present invention is not limited to the foregoing embodiment but is subject to various modifications and variations within the scope and spirit of the appended claims. | There is disclosed an image forming apparatus for overlaying plural images in succession, in which a downstream image overlay is controlled in timing by an upstream image overlay, in order to avoid positional aberrations in the supperposed multiple images. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to corrugated paperboard containers, and more particularly to a closure construction for such containers.
Container set-up time and production output are proportionately related; the longer it takes to erect a container, the less will be the line output of a packer. The object being to form a bottom closure arrangement that can be simply and quickly assembled. Conventional containers, such as the container shown in U.S. Pat. No. 4,279,379, are not suitable for fast set-up, as is contemplated by the present invention, because they require an additional step in assembly. After the bottom closure flaps or panels have been correctly positioned relative to one another with the locking tabs inserted in their respective holes, slots, or slits, provided for such engagement, the panels then must be lifted, or pushed from inside the container, by hand to a fully assembled position.
Sometimes, heavy packaging contents provide the necessary force to lock together the bottom panels. However, when packing light items, such as bags of potato chips, additional manual manipulation of the prior art container is required to achieve a completely locked bottom closure.
SUMMARY OF THE INVENTION
It, therefore, is an object of this invention to provide an improved bottom closure construction for a container which will allow rapid assembly to minimize container set-up time.
Appropriately shaped holes or slots in the bottom lock panels permit a fast-locking action without any binding as in conventional containers that are designed for interference fit. When the lock tab "pops" into position, panel tension alone causes the lock to slide into position for a substantially flat bottom ready for packing without additional manipulation by the packer.
Other objects, features and advantages of the present invention will be more fully understood from the following detailed description of a preferred embodiment of the invention, especially when that description is read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the cut and scored corrugated paperboard blank from which the container illustrated in FIGS. 2 through 9 is assembled;
FIG. 2 is a perspective view of the partially assembled container;
FIG. 3 is an enlarged cross-sectional view taken along line 3--3 of FIG. 2;
FIGS. 4, 6 and 8 are fragmentary plan views illustrating the container of FIG. 2 in various stages of assembly;
FIG. 5 is an enlarged fragmentary cross-sectional view taken along line 5--5 of FIG. 4;
FIG. 7 is an enlarged fragmentary cross-sectional view taken along line 7--7 of FIG. 6; and
FIG. 9 is an enlarged fragmentary cross-sectional view taken along line 9--9 of FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 of the drawings, the numeral 20 denotes generally the blank of this invention, the blank being formed of a single piece of stiff, foldable and resilient material such as corrugated paperboard. The blank 20 can be divided into three main portions including a top portion 22, a central portion 24, and a bottom portion 26.
The central portion 24 of the blank 20 is comprised of a plurality of body panels between transverse fold lines 30, 31 which become the sides of the container when erected. The central portion 24 includes a first side panel 32, a front panel 33, a second side panel 34, a rear panel 35, and a glue flap 36, conventionally carrying an adhesive, which are foldably connected to one another in series along respective longitudinal fold lines 37, 38, 39, 40.
It should be understood, however, that references in this description to "front", "rear", and "side" are for convenience of description, and such terms are not intended to be used in a limiting way.
The top portion 22 of the blank 20 is comprised of top closure panels 50, 51, 52, 53 foldably connected to, and integral with, upper ends of the panels 32, 33, 34, 35, respectively, along the fold line 30. The top closure panels are separated from their adjacent counterpart by slits 55 to permit them to be independently folded in a conventional manner.
The bottom portion 26 of the blank 20 is comprised of bottom closure panels 60, 61, 62, 63 foldably connected to, and integral with, lower ends of the body panels 32, 33, 34, 35, respectively, along the fold line 31.
Panels 60, 62 form the lock panels of the bottom closure of the container. Each bottom lock panel 60, 62 is foldably connected to a lower end of the non-adjacent body panels 32, 34, respectively, along the fold line 31.
A cut out slot 70 is formed in the bottom lock panel 60 and is comprised of at least three (3) substantially straight edges 71, 72, 73. Still referring to FIG. 1, preferably the first edge 71 of slot 70 is cut relative to a line which is substantially perpendicular to the fold line 31. At one end of first slot edge 71 remote from the fold line 31, the second slot edge 72 is cut so that preferably it is inclined from the first slot edge at an angle β 1 of approximately 50 degrees. However, it is contemplated that the second slot edge 72 can form an angle between about 46 degrees and about 51 degrees, inclusive, with the first slot edge 71. Preferably, the third slot edge 73, at the other end of first slot edge 71 proximate to the fold line 31, is cut along a line that is inclined from such first slot edge at an angle β 2 of approximately 120 degrees. However, it is contemplated that the third slot edge 73 can form an angle between about 119 degrees and about 121 degrees, inclusive, with the first slot edge 71.
A cut out slot 75 formed in lock panel 62 also has at least three (3) substantially straight edges 76, 77, 78 which are similarly situated with respect to the fold line 31 and each other, as in the case of edges 71, 72, 73 of the slot 70, because lock panel 62 is a mirror image of lock panel 60.
Preferably, the slots 70, 75 are formed with rounded corners to minimize potential tearing when the lock is put under load.
Panel 61 forms the tuck panel of the bottom closure of the container. It is foldably connected to a lower end of body panel 33, one of the other two (2) non-adjacent body panels 33, 35, along the fold line 31.
Panel 63 forms the tab panel of the bottom closure of the container. It is foldably connected to a lower end of body panel 35 along the fold line 31. The bottom tab panel 63 is formed with a pair of oppositely disposed tabs 80, 81 situated at a free end of the panel. Preferably, each tab 80, 81 is formed with at least two (2) connected, substantially straight edges. Preferably, a first tab edge 82, 83 of tab 80, 81, respectively, is cut relative to a line which is substantially parallel to the fold line 31, while a respective second tab edge 84, 85 is cut so that preferably it is inclined from the first tab edge at an angle β 3 of approximately 107 degrees. However, it is contemplated that the second tab edge 84, 85 can form an angle between about 103 degrees and about 108 degrees, inclusive, with the first tab edge 82, 83, respectively. (see FIG. 1).
The container is initially formed from the blank 20 by folding body panels 32, 33, 34, 35 about the fold lines 37, 38 39. Then the glue flap 36 is folded about its fold line 40 and is glued to the inner surface of the body panel 32. Clearly, other conventional methods of attaching the flap to the body panel, or of directly attaching body panel 35 to body panel 32, can be used instead of an adhesive. It will be noted that the container as partially assembled up to this point can be folded or collapsed flat for easy shipment and storage. Final assembly of the container is usually performed by the packer.
At the packing location, the flat container assembly is opened to form a tube, and the top closure panels 50, 51, 52, 53 can be folded outwardly, as shown in FIG. 2, while the bottom closure is formed first. The bottom tuck panel 61 is folded inwardly about fold line 31 until it is substantially perpendicular to the body panels 32, 33, 34, 35. Thereafter, the bottom lock panels 60, 62 are folded inwardly about fold line 31 until they overlie the bottom tuck panel 61, and then bottom tab panel 63 is folded inwardly about fold line 31 until it overlies the bottom lock panels 60, 62 as illustrated in FIG. 2.
Referring now to FIG. 4, the bottom tab panel 63 is forced inwardly into the container, thereby also forcing the bottom lock panels 60, 62 into the container interior as tabs 80, 81 slide along the outside surfaces of such lock panels at their respective second tab edges 84, 85. The inwardly moving bottom lock panels 60, 62 force the bottom tuck panel 61 into the container interior as well. As illustrated in FIGS. 4 and 5, the second tab edges 84, 85 are preferably aligned with the third slot edges 73, 78, respectively, at this stage of assembly. Force is continuously applied to the bottom tab panel 63 as the first tab edges 82, 83 unite with the first slot edges 71, 76, respectively, (see FIGS. 6 and 7), and pass by each other without interference until the bottom tab panel 63 comes to rest adjacent the second slot edges 72, 77, as illustrated in FIG. 7 in phantom. There is usually a characteristic "pop" sound that occurs when the respective tab and slot edges clear one another. The appropriately shaped slots 70, 75, particularly the second slot edges 72, 77 thereof ensure that the bottom tab panel 63 is pushed sufficiently far into the container interior so that, when the bottom tab panel is released, tension in the flexed bottom panels causes the lock (slots 70, 75) to slide into position for a substantially flat bottom ready for packing without additional manipulation by the packer. The notches 90, 91, formed in the bottom tab panel 63, allow a greater proportion of the tabs 80, 81 to project into the slots 70, 75, respectively. The engagement of the tabs with the bottom lock panels self-locks the container bottom closure.
While a preferred embodiment of the invention has been shown and described, it should be understood that there may be other container constructions and modifications which fall within the spirit and scope of this invention as defined by the following claims. | This invention is directed to an improved container made of corrugated paperboard or the like. Appropriately shaped slots in the bottom lock panels permit a fast-locking action without any binding as in conventional containers that are designed for interference fit. | 1 |
FIELD OF THE INVENTION
The present invention relates generally to transcranial electrical stimulation, and more particularly transcranial electrical stimulation during sleep.
BACKGROUND OF THE INVENTION
In recent years, evidence has accumulated on the efficacy of transcranial electrical stimulation, using both direct current (transcranial direct current stimulation, tDCS), alternating current (transcranial alternating current stimulation, tACS), and random current (transcranial random noise stimulation, tRNS). Direct current stimulation has the ability to selectively sensitize or desensitize a particular brain area. Alternating current has the ability to entrain brain oscillations strengthening the EEG signal spectrum in a certain frequency band. Stimulation using random noise current induces consistent excitability in the target brain region.
Direct current stimulation applied during sleep has been shown to facilitate memory consolidation.
40 Hz alternating current stimulation applied during REM sleep has been shown to induce a state of consciousness known as “Lucid Dreaming”, in which the person becomes aware that he is dreaming while he is dreaming. Lucid dreaming has potential applications ranging from entertainment to treatment of PTSD and nightmares, and enhancement of athletic performance.
Many more applications of electrical brain stimulation during sleep are likely to emerge, such as reducing susceptibility to noise and possibly modulating sleep phases.
Currently there are no reports of adverse side effects from tDCS, tACS and tRNS, aside from mild itching and redness on the skin underneath the stimulation electrodes. The reason is that unlike electroconvulsive therapy, the currents used in modern brain stimulation techniques are extremely small. The stimulation is not meant to force neurons to fire in a specific pattern, but only to increase their natural likelihood to do so. The brain can be viewed as a multi-stable dynamic system which is sensitive to outside “nudges”. For this reason even a small current can have an impact on the overall functioning of the brain.
Unfortunately, attempting to affect the functioning of specific areas of the brain with electrical stimulation during sleep is currently a difficult undertaking, requiring medical expertise, skilled electrode positioning and application, and the involvement of a doctor or researcher throughout the stimulation.
In transcranial electrical stimulation research, it is common to monitor the EEG signal of a patient before and after stimulation, to verify whether the stimulation has had effects on the EEG spectrum. For example, alternating current stimulation can be used to potentiate frequencies around 40 Hz, and this effect can be verified by comparing the intensity of the patient's endogenous 40 Hz EEG waves before and after stimulation.
Transcranial electrical stimulation researchers normally utilize a clinical EEG monitoring device and a separate transcranial stimulation device. Electrodes are carefully applied in predetermined positions on the subject's scalp by medical personnel. Particular care is taken to ensure low impedance of the electrodes, particularly the stimulation electrodes, so as to reduce itching and redness.
A few costly devices are now available on the medical device market that allow both EEG monitoring and stimulation. The StarStim™ by Neuroelectrics is an EEG cap with a multitude of holes onto which a large variety of types of electrodes can be mounted (for instance, Ag—AgCl EEG electrodes, or sponge-type stimulation electrodes requiring periodic application of saline solution). Mounting the correct electrode type at the correct location is the responsibility of the doctor or researcher. Further, each electrode can be electrically configured to capture the EEG signal or apply a stimulation current. The configuration is controlled by medical personnel using a computer interface. This EEG cap is not suitable for, nor intended for, use during sleep. The battery is placed on the back of the head, thereby limiting the patient's sleeping position, and—for safety reasons—the product has been engineered to have an automatic shutdown time of 1 hour, thereby precluding its use throughout a full night's sleep.
In recent years, consumer devices have emerged which allow a user to monitor his/her EEG without the supervision of a medical practitioner. Such devices typically include a headband worn around the user's head, several EEG electrodes, and a small EEG monitoring device which is either embedded in the headband or structurally and electrically connected to the headband by means of snap fasteners, such as snap connectors.
The Zeo™ headband (by Zeo, Inc.) now out of production allowed monitoring of EEG signal bands during sleep to perform sleep staging. Many other commercial EEG headbands now exist on the consumer market (such as the Muse™ by Interaxon, or the Melon™ headband), though they are generally intended for wake-time EEG monitoring.
All these consumer devices do not include circuitry for brain stimulation, and even if they did the electrodes would be incapable of safely applying electrical current stimulation to the brain.
The Foc.us™ headset is at the time of writing the only commercially available tDCS headset which can be used by a user to self deliver transcranial direct current stimulation. However it is sold for the purpose of day time stimulation. Even if it was worn during sleep, it would be of no value because it would fall off.
SUMMARY OF THE INVENTION
The headgear of the invention provides a simple to use and safe platform for wearing consumer-type dual use brain stimulation and monitoring devices during sleep.
The headgear enables a user to sleep comfortably while wearing electrodes needed for both EEG monitoring and transcranial electrical stimulation. The headgear can accept and support a miniaturized dual use monitoring/stimulation device on the forehead or the top of the head, where the bulk of the monitoring/stimulation device will not interfere with the user's sleeping position. The headgear takes the guesswork out of electrode placement, because the electrodes are prepositioned or are easily adjustable according to a predetermined pattern of electrode placement, and are appropriately sized to allow comfortable transcranial stimulation without producing skin irritation, and without awakening the user.
One general aspect of the invention is a dual purpose sleep wearable headgear for both monitoring and stimulating the brain of a sleeping person. The headgear includes: one or more flexible bands capable of being worn so as to capture the head of the sleeping person; a plurality of electrodes sized and located so as to be capable of applying electrical stimulation to the sleeping person's brain, at least some of the plurality of electrodes also being capable of acquiring an EEG signal; a plurality of electrode connectors, capable of receiving the plurality of electrodes, each electrode connector being incorporated into one of the flexible bands so as to direct the electrical stimulation to an underlying portion of the sleeping person's brain; and a plurality of interface connectors for electrically connecting an electronic circuit to the headgear, the electronic circuit being capable of both acquiring the EEG signal and applying the electrical stimulation, each interface connector being electrically connected to at least one of the plurality of electrode connectors.
In some embodiments, some interface connectors are electrically connected to at least one of the plurality of electrode connectors using one of: a wire; a conductive fabric strip; a conductive thread; and a flexible circuit board.
In some embodiments, at least one electrode of the plurality of electrodes includes at least one of: a layer of electrically conductive gel; a layer of electrically conductive fabric; a sponge-like porous body capable of retaining water; and a nanostructured conductive layer. A nanostructured layer can include carbon nanotubes, gold nanostructures, a nanoparticle layer, a fractal nanostructure.
In some embodiments, at least one of the plurality of interface connectors is one of: an electrical snap connector; or a piece of conductive Velcro®; or a magnet.
In some embodiments, at least one of the one or more flexible bands is capable of structurally supporting the bulk of an enclosure enclosing the electronic circuit, so as to support the enclosure at a predetermined position on the sleeping person's head, the predetermined position selected so as to avoid substantially interfering with the sleeping person's sleep.
Another general aspect of the invention is a dual purpose sleep wearable headgear for both monitoring and stimulating the brain of a sleeping person. This headgear includes: one or more flexible bands capable of being worn so as to capture the head of the sleeping person; a plurality of electrodes sized and located so as to be capable of applying electrical stimulation to respective locations on the sleeping person's head, at least some of the plurality of electrodes also being capable of acquiring an EEG signal at the same respective locations, each electrode of the plurality of electrodes being incorporated into one of the one or more flexible bands so as to direct the electrical stimulation to an underlying portion of the sleeping person's brain; and a plurality of interface connectors for electrically connecting an electronic circuit to the headgear, the electronic circuit being capable of both acquiring the EEG signal and applying the electrical stimulation, each interface connector being electrically connected to at least one of the plurality of electrodes.
In some embodiments, some interface connectors are electrically connected to at least one of the plurality of electrodes using one of: a wire; a conductive fabric strip; a conductive thread; and a flexible circuit board.
In some embodiments, at least one electrode of the plurality of electrodes includes at least one of: a layer of electrically conductive gel; a layer of electrically conductive fabric; a sponge-like porous body capable of retaining water; and a nanostructured conductive layer.
In some embodiments, at least one of the plurality of interface connectors is one of: an electrical snap connector; or a piece of conductive hook and loop material; or a magnet.
In some embodiments, at least one of the one or more flexible bands is capable of structurally supporting the bulk of an enclosure enclosing the electronic circuit, so as to support the enclosure at a predetermined position on the sleeping person's head, the predetermined position selected so as to avoid substantially interfering with the sleeping person's sleep.
Another general aspect of the invention is a dual purpose sleep wearable headgear for both monitoring and stimulating the brain of a sleeping person. This headgear includes: one or more flexible bands capable of being worn so as to capture the head of the sleeping person; a plurality of stimulation electrodes, each stimulation electrode being sized and located so as to be capable of applying electrical stimulation to an underlying portion of the sleeping person's brain; a plurality of EEG electrodes, each EEG electrode being capable of acquiring an EEG signal from an underlying portion of the sleeping person's brain; a plurality of stimulation electrode connectors, each stimulation electrode connector being capable of receiving a stimulation electrode, each stimulation electrode connector being incorporated into one of the flexible bands so as to direct the electrical stimulation to an underlying portion of the sleeping person's brain; a plurality of EEG electrode connectors, each EEG electrode connector being capable of receiving an EEG electrode, each EEG electrode connector being incorporated into one of the flexible bands so as to acquire an EEG signal from an underlying portion of the sleeping person's brain; and a plurality of interface connectors for electrically connecting an electronic circuit to the headgear, the electronic circuit being capable of both acquiring the EEG signal and applying the electrical stimulation, each interface connector being electrically connected to either a stimulation electrode connector or an EEG electrode connector.
In some embodiments, some interface connectors are electrically connected to at least one of: a stimulation electrode connector; and an EEG electrode connector, using one of: a wire; a conductive fabric strip; a conductive thread; and a flexible circuit board.
In some embodiments, at least one electrode of the plurality of electrodes includes at least one of: a layer of electrically conductive gel; a layer of electrically conductive fabric; a sponge-like porous body capable of retaining water; and a nanostructured conductive layer.
In some embodiments, at least one of the plurality of interface connectors is one of: an electrical snap connector; or a piece of conductive hook and loop material; or a magnet.
In some embodiments, at least one of the one or more flexible bands is capable of structurally supporting the bulk of an enclosure enclosing the electronic circuit, so as to support the enclosure at a predetermined position on the sleeping person's head, the predetermined position selected so as to avoid substantially interfering with the sleeping person's sleep.
Another general aspect of the invention is a dual purpose sleep wearable headgear for both monitoring and stimulating the brain of a sleeping person. This headgear includes: one or more flexible bands capable of being worn so as to capture the head of the sleeping person; a plurality of stimulation electrodes, each stimulation electrode sized so as to be capable of applying electrical stimulation to the sleeping person's brain, each stimulation electrode being incorporated into one of the flexible bands so as to direct the electrical stimulation to an underlying portion of the sleeping person's brain; a plurality of EEG electrodes, each EEG electrode being capable of acquiring an EEG signal from the sleeping person's head, each EEG electrode being incorporated into one of the flexible bands so as to acquire an EEG signal from an underlying portion of the sleeping person's brain; and a plurality of interface connectors for electrically connecting an electronic circuit to the headgear, the electronic circuit being capable of both acquiring the EEG signal and applying the electrical stimulation, each interface connector being electrically connected to either a stimulation electrode or an EEG electrode.
In some embodiments, some interface connectors are electrically connected to at least one of: a stimulation electrode; and an EEG electrode, using one of: a wire; a conductive fabric strip; a conductive thread; and a flexible circuit board.
In some embodiments, at least one electrode of the plurality of electrodes includes at least one of: a layer of electrically conductive gel; a layer of electrically conductive fabric; a sponge-like porous body capable of retaining water; and a nanostructured conductive layer.
In some embodiments, at least one of the plurality of interface connectors is one of: an electrical snap connector; or a piece of conductive hook and loop material; or a magnet.
In some embodiments, at least one of the one or more flexible bands is capable of structurally supporting the bulk of an enclosure enclosing the electronic circuit, so as to support the enclosure at a predetermined position on the sleeping person's head, the predetermined position selected so as to avoid substantially interfering with the sleeping person's sleep.
Another general aspect of the invention is a method for stimulating the brain of a sleeping person. The method includes: attaching a flexible headgear to the head of the sleeping person, the headgear having a plurality of electrodes, affixing a dual use EEG monitoring and electrical stimulation device to the sleep wearable headgear, electrically connecting the dual use EEG monitoring and stimulation device to the plurality of electrodes, analyzing the EEG of the sleeping person's brain so as to detect a stimulation start condition, and applying an electrical potential to two or more of the plurality of electrodes, so as to deliver an electrical current to the sleeping person's brain in response to the stimulation start condition.
In some embodiments, the stimulation signal condition is one of: a sleep phase; a period of time after entering a sleep phase; and a sleep EEG feature as in a sleep spindle.
In some embodiments, the electrode potential is variable, so as to deliver a time variable electrical current to the sleeping person's brain in response to the stimulation start condition, the time variable electrical current being one of: an alternating current, or a random noise electrical current.
In some embodiments, the magnitude of the electrical current is increased gradually so as to reduce discomfort and avoid disturbing the person's sleep.
In some embodiments, the electrical current is delivered so as to induce a lucid dream.
In some embodiments, the electrical current is an alternating current of a frequency between 30 and 50 hertz.
In some embodiments, the method also includes an electrode impedance reporting phase after the attaching a dual use EEG monitoring and stimulation device to the sleep wearable headgear, so as to allow the person to adjust the headgear or add conductive paste to the headgear's electrodes until the electrode impedance is sufficiently low for stimulation to occur safely.
In some embodiments, the stimulation start condition is not permitted to proceed when the impedance of the stimulation electrodes is too high for stimulation to occur safely.
Another general aspect of the invention is a dual purpose sleep wearable electronic headgear for both monitoring and stimulating the brain of a sleeping person. The electronic headgear includes: a dual use EEG monitoring and stimulation electronic circuit, capable of both acquiring an EEG signal and producing a stimulation current; an enclosure enclosing the electronic circuit; a flexible headgear capable of being worn so as to capture the sleeping person's head, the headgear also being capable of structurally supporting the bulk of the enclosure, so as to support the enclosure at a predetermined location on the sleeping person's head, the predetermined location being selected so as to avoid substantially interfering with the sleeping person's sleep; a device-mounted electrode, sized so as to be capable of applying electrical stimulation to the sleeping person's head, the device-mounted electrode also capable of being connected to the dual use EEG monitoring and stimulation electronic circuit; and a headgear-mounted electrode, sized so as to be capable of applying electrical stimulation to the sleeping person's head, the headgear-mounted electrode being incorporated into the headgear, or capable of being affixed to the headgear at a predetermined location, the predetermined location selected so as to direct the electrical stimulation to an underlying portion of the sleeping person's brain.
In some embodiments, the EEG signal is monitored through the device-mounted electrode and the headgear-mounted electrode.
In some embodiments, the electronic headgear further includes at least one additional device-mounted electrode or at least one additional headgear-mounted electrode.
In some embodiments, the device-mounted electrode is connected to the dual use EEG monitoring and stimulation electronic circuit using at least one of: a snap contact; and a wire connector.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more fully understood by reference to the Detailed Description, in conjunction with the following figures, wherein:
FIG. 1 is a line drawing of a person shown wearing a simple embodiment of the sleep-wearable headgear of the invention.
FIG. 2A and FIG. 2A ′ are schematic drawings of an outer view and an inner view of the sleep wearable headgear of FIG. 1 .
FIG. 2B and FIG. 2B ′ are schematic drawings of an outer view and an inner view of an alternate embodiment of the sleep wearable headgear of FIG. 1 , further including a right leg drive electrode.
FIG. 2C and FIG. 2C ′ are schematic drawings of an alternate embodiment of the sleep wearable headgear of the invention, this embodiment including both EEG electrodes and stimulation electrodes.
FIG. 2D and FIG. 2D ′ are schematic drawings of an alternate embodiment of the sleep wearable headgear of the invention, this embodiment including Ag—AgCl EEG electrodes.
FIG. 3A is a line drawing of a wearable dual use brain monitoring and stimulation device suited for being connected to the embodiments of FIG. 2A and FIG. 2B of the sleep wearable headgear of the invention.
FIG. 3B is a line drawing of an alternate embodiment of the wearable dual use brain monitoring and stimulation device of FIG. 3A , this embodiment including a pulse oximetry sensor.
FIG. 4 is a line drawing of a person shown wearing the wearable dual use brain monitoring and stimulation device of FIG. 3A and FIG. 3B mounted on the headgear of FIG. 2A and FIG. 2B .
FIG. 5 is a line drawing of a person shown wearing an alternate embodiment of the headgear of the invention, this embodiment including multiple flexible bands and interface connectors located at the top of the person's head.
FIG. 6 and FIG. 6 ′ are schematic drawings of an outer view and an inner view of the sleep wearable headgear of FIG. 5 .
FIG. 7 is a line drawing of a person shown wearing a dual use brain monitoring and stimulation device, the device being attached to the headgear of FIG. 5 .
FIG. 8 is a line drawing of a bottom view of the dual use brain monitoring and stimulation device of FIG. 7
FIG. 9 and FIG. 9 ′ are schematic drawings of an outer view and an inner view of an alternate embodiment of the headgear of FIG. 5 , this embodiment including both EEG electrodes and stimulation electrodes.
FIG. 10 and FIG. 10 ′ are schematic drawings of an outer view and an inner view of an alternate embodiment of the headgear of FIG. 5 , this embodiment being the same as the embodiment of FIG. 9 and FIG. 9 ′, including banana plug connectors instead of snap connectors.
FIG. 11 and FIG. 11 ′ are schematic drawings of an outer view and an inner view of an alternate embodiment of the headgear of FIG. 1 , this embodiment including electrode connectors which allow the electrodes to be replaceable.
FIG. 12 is a line drawing of a minimal embodiment of the wearable dual use brain monitoring and stimulation device of FIG. 3A , the embodiment including a wire connector plug and only one female snap connector.
FIG. 13 is a line drawing of the dual use device of FIG. 12 , showing one replaceable, dual use electrode connected to the dual use device of FIG. 12
FIG. 14 is a line drawing of a person shown wearing the dual use device of FIG. 13 , the dual use device being supported by a single-electrode, single-band headgear.
FIG. 15 and FIG. 15 ′ are schematic drawings of an outer view and an inner view of the embodiment of FIG. 14 , the embodiment including only one dual use headgear-mounted electrode.
FIG. 16 is a line drawing of a person shown wearing an alternate embodiment of the dual use device of FIG. 13 , this embodiment including a displaced electrode connected by a wire.
FIG. 17 is a flow chart of a process for stimulating the brain of a sleeping person.
FIG. 18 is a flow chart of an alternate embodiment of the process of FIG. 17 , the embodiment also including an electrode impedance reporting step.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a simple embodiment of the sleep-wearable headgear 100 worn by a person 106 , the sleep-wearable headgear 100 essentially being a flexible band having a non-stretchable portion 108 . The non-stretchable portion 108 includes two frontal interface connectors 102 and two lateral interface connectors 104 . The non-stretchable portion 108 ensures that the distance between the interface connectors remains fixed even while the headgear 100 is stretching to accommodate the person's 106 head. In the embodiment shown in FIG. 1 , the interface connectors are electrical snap connectors.
In FIG. 2A and FIG. 2A ′, both sides of the headgear 100 of FIG. 1 are shown in detail. When the headgear is worn, three electrodes are in contact with the person's 106 forehead: a frontal dual use electrode 202 , and two lateral dual use electrodes 204 . Velcro® hooks 208 and Velcro® loops 206 allow the headgear to be adjusted to fit comfortably around the person's 106 head, tightly enough to ensure good contact between the electrodes and the person's 106 forehead. Velcro® is a brand of hook and loop material, and Velcro® can refer either to the hook material, the cooperative loop material, or a combination of both. Two frontal interface connectors 102 and two lateral interface connectors 104 are located at the front of the headgear, allowing a wearable dual use brain monitoring and stimulation device 300 (such as the device shown in FIG. 3A ) to be connected to and supported by the headgear.
Snap prong connectors are commonly available fasteners used in garments. They are composed of two halves, a top part and a bottom part. The bottom part includes the prongs. For each electrical snap connector labeled on the outer view ( FIG. 2A ), a corresponding circle is shown on the inner view ( FIG. 2A ′), this represents the electrically conductive bottom half of the snap connector (the prongs side).
The frontal dual use electrode 202 is electrically connected to the frontal interface connectors 102 . The lateral dual use electrodes 204 are electrically connected to the lateral interface connectors 104 with two wires 200 .
The electrodes 202 , 204 shown in FIG. 2A and FIG. 2A ′ are gel electrodes, but other types of electrodes can be substituted as long as the surface area with the skin is sufficient, and the impedance of the electrodes is sufficiently low. The wires 200 can be substituted by strips of conductive fabric, conductive threads, or flexible printed circuit boards.
This embodiment allows monitoring of two EEG channels (left and right hemispheres). During monitoring, the frontal dual use electrode 202 is used as a reference electrode, while the lateral dual use electrodes 204 are used to acquire the left and right channel EEG signals.
This embodiment also allows delivery of electrical transcranial stimulation of different strengths to the left and right lobe. During stimulation, an electrical waveform of different amplitude is applied to each of the lateral dual use electrodes 204 to achieve a different stimulation strength to the left and right lobes.
Four interface connectors are not strictly required in this embodiment. The two frontal interface connectors 102 are already electrically connected and could be replaced by a single interface connector, yielding an embodiment with only three interface connectors. Further, the lateral dual use electrodes 204 could also be electrically connected, provided that a single EEG channel is sufficient for monitoring purposes, and that the strength of the electrical stimulation to be carried out is identical for both hemispheres. In this case, only two interface connectors would be necessary for both stimulation and EEG.
The electrode positioning utilized in FIG. 2A and FIG. 2A ′ allows a number of stimulation strategies, during both wake and sleep.
FIG. 2B and FIG. 2B ′ show a slightly more complex embodiment. In this figure, the headgear 100 includes a dual use right leg drive electrode 212 . During EEG monitoring, the wearable dual use brain monitoring and stimulation device 300 utilizes the dual use right leg drive electrode 212 as an output to cancel the common-mode voltage and reduce noise in the EEG signal. Use of a right leg drive electrode is popular and well known in the art. During stimulation, in order to reclaim electrode surface area, the wearable dual use brain monitoring and stimulation device 300 can ensure that the dual use right leg drive electrode 212 is kept at equal electrical potential with the frontal dual use electrode 202 . By so doing, the stimulation area is not decreased by the use of a right leg drive electrode. A large stimulation area minimizes the discomfort associated with electrical stimulation, and prevents unwanted awakenings when the stimulation is carried out during sleep.
The embodiment of FIG. 2B and FIG. 2B ′ also has a hole 213 . The hole 213 enables acquisition of reflectance pulse oximetry data (including heart rate and blood oxygenation) when the wearable dual use brain monitoring and stimulation device 300 also includes a suitably located and calibrated pulse oximetry sensor 304 (shown in FIG. 3B )
In EEG monitoring, EEG signal quality is inversely proportional to the impedance of the electrodes used to acquire the EEG signal. The higher the impedance of the EEG electrodes, the lower the signal-to-noise ratio of the acquired EEG signal. Small EEG electrodes can be used as long as their impedance is low. Water gel Ag—AgCl electrodes are common in EEG recording. The sensing area is small, but their impedance is low. Electrodes for stimulation on the other hand require not only low impedance, but also a sufficiently large surface area. This is because the discomfort induced by electrical stimulation is proportional to the current density (expressed in units of current per unit surface area, for instance mA/cm 2 ). The minimum electrode surface area reported in the literature for electrical stimulation is 3.5 cm 2 but electrode areas of at least 12 cm 2 are common. Discomfort in a waking person is a simple inconvenience, but when stimulation is used to modify the characteristics of a person's sleep, discomfort can negate the benefits of the stimulation, because it can awaken the person. Therefore, for stimulation carried out during sleep, electrode size should be maximized to the extent allowed by the space available.
The present invention can be realized without dual use electrodes. In FIG. 2C and FIG. 2C ′, an alternate embodiment of the headgear of FIG. 2B and FIG. 2B ′ is shown that uses one set of EEG electrodes for EEG monitoring and a separate set of stimulation electrodes for electrical stimulation. This can reduce the surface area available for the electrical stimulation, but not by much if the EEG electrodes are kept sufficiently small. On the other hand, dual use electrodes require additional complexity in the electronics of the wearable dual use brain monitoring and stimulation device 300 , so the embodiment shown in FIG. 2C and FIG. 2C ′ allows use of simpler electronic circuitry for the monitoring and stimulation.
In FIG. 2C and FIG. 2C ′, the EEG is monitored using three EEG electrodes: the frontal EEG electrode 226 and two lateral EEG electrodes 220 . Each lateral EEG electrode 220 is connected by a lateral EEG wire 216 to a lateral EEG interface connector 214 . The frontal EEG electrode 226 is connected to the frontal EEG interface connector 232 directly. Stimulation is delivered through three stimulation electrodes, larger in size than the EEG electrodes. The stimulation electrodes are the frontal stimulation electrode 218 and the lateral stimulation electrodes 224 . Each lateral stimulation electrode 224 is connected by a lateral stimulation wire 228 to a lateral stimulation interface connector 230 . The frontal stimulation electrode 218 is connected to the frontal stimulation interface connector 210 directly.
In FIG. 2D and FIG. 2D ′ another embodiment is illustrated, in which the EEG electrodes are Ag—AgCl electrodes. This type of electrode allows higher quality EEG recording. The frontal EEG Ag—AgCl electrode 236 and the lateral EEG Ag—AgCl electrodes 222 are connected in an identical way to FIG. 2C . They contain an Ag—AgCl element 234 , covered by gel.
Alternate embodiments are possible, which utilize permutations of the variations described. Other possible variations include using interface connectors other than snap connectors, and using conductive textiles as electrodes. Conductive textiles however have higher impedances; this may be acceptable if the quality of the monitored EEG signal is less important than patient comfort, however conductive textiles available at the time of writing are normally not suited for stimulation. A stimulation electrode made with conductive textile material is possible but would require careful application of conductive EEG paste prior to sleep. Carbon nanotube electrodes and other electrodes based on nanostructures (still in development as of the time of writing) may soon be used for both EEG monitoring and stimulation, and require no conductive paste application.
FIG. 3A shows a wearable dual use brain monitoring and stimulation device 300 suited for being connected to the headgears of FIG. 2A and FIG. 2B . Four female snap connectors 302 mate with the male snap connectors on the headgear (for instance, interface connectors 102 , 104 in FIG. 2B and FIG. 2B ′), providing structural and electrical connection. In FIG. 3B an alternative embodiment of the device 300 is shown that also includes a pulse oximetry sensor 304 , whose position and size matches the hole 213 of FIG. 2B and FIG. 2B ′. The pulse oximetry sensor 304 is can be used, for instance, to acquire the heart rate from the sleeping person 106 . The heart rate can be used, for instance, to detect whether the person 106 is being adversely affected by the stimulation, and terminate the stimulation in response to any adverse reaction.
FIG. 4 shows the wearable dual use brain monitoring and stimulation device 300 of FIG. 3A and FIG. 3B mounted on the headgear 100 of FIG. 2A and FIG. 2B , and worn by a person 106 .
FIG. 5 shows a multi-band headgear 500 for both monitoring and stimulating the brain of a sleeping person 106 . The multi-band headgear 500 has interface connectors 102 , 104 , 602 located at the top of the person's 106 head.
FIG. 6 and FIG. 6 ′ show the details of a possible embodiment of the multi-band headgear 500 of FIG. 5 , best understood in reference to the headgear 100 embodiment of FIG. 2A . A multi-band headgear allows a dual use monitoring and stimulation device to be secured to the top of the head. This is useful when the size of the device cannot be sufficiently miniaturized, or when forehead placement would interfere with some sleeping positions. The drawback is higher complexity, construction costs, and potential interference to the EEG signal resulting from the plurality of wires required.
In the multi-band headgear 500 of FIG. 6 , the frontal dual use electrode 202 and lateral dual use electrodes 204 are positioned at locations on the person's 106 forehead at locations identical to FIGS. 2A, 2B, 2C, and 2D . Each lateral dual use electrode 204 is, as in FIG. 2A , electrically connected to a lateral interface connector 104 by a lateral wire 200 . However, in FIG. 6 the lateral interface connectors 104 are located on the left support structure 612 and the right support structure 616 . The frontal dual use electrode 202 is connected to a single frontal interface connector 102 by a frontal wire 600 . The frontal interface connector 102 is located on the anterior support structure 614 .
When worn, the multi-band headgear 500 is first secured around the head of the person 106 by the horizontal Velcro® loops 206 and horizontal Velcro® hooks 208 . The anterior support structure 614 and the posterior support structure 618 are then joined by means of the anterior support structure Velcro® loops 604 and the posterior support structure Velcro® hooks 606 . Similarly, the left support structure 612 is joined with the right support structure 616 by means of the left support structure Velcro® loops 608 and the right support structure Velcro® hooks 610 , completing the assembly and capturing the person's 106 head.
In FIG. 6 and FIG. 6 ′ one additional interface connector 602 on the rear support structure 618 is not electrically connected but provides symmetry and structural support.
FIG. 7 shows an over-the-head dual use brain monitoring and stimulation device 700 , mated to the interface connectors of the multi-band headgear 500 .
FIG. 8 shows the bottom side of the over-the-head dual use brain monitoring and stimulation device 700 , and the female snap connectors 302 by which it is electrically and structurally connected to the multi-band headgear 500 .
FIG. 9 and FIG. 9 ′ show an alternate embodiment of the multi-band headgear 500 . Like the headgear of FIG. 2B and FIG. 2B ′, this embodiment has two sets of electrodes, the electrodes used for EEG monitoring are smaller and the electrodes used for stimulation are larger. The frontal EEG electrode 226 is connected by a frontal EEG wire 600 to the frontal EEG interface connector 232 . The frontal stimulation electrode 218 is connected by a frontal stimulation wire 900 to the frontal stimulation interface connector 210 .
FIG. 10 and FIG. 10 ′ show an alternative to the use of snap connectors as interface connectors. Here, the interface connectors are small banana plugs 1000 which can be plugged into a suitably modified over-the-head dual use brain monitoring and stimulation device 700 , the device 700 having banana plug receptacles instead of female snap connectors 302 . The plurality of banana plugs 1000 can provide sufficient structural support as well as electrical connectivity. Many more embodiments of the multi-band headgear 500 are possible; for instance, using Ag—AgCl electrodes as EEG electrodes, or modifying the number and shape of the support structures, or modifying the way in which the headgear is fastened to the head of the person 106 .
FIG. 11 and FIG. 11 ′ show an alternative embodiment of the headgear 100 of FIG. 2A and FIG. 2A ′. In this embodiment, the electrodes are replaceable and can be connected to electrode connectors 1102 located at predetermined locations along the headgear 100 . By making the electrodes replaceable, the headgear does not need to be discarded when the electrodes wear out. All headgear embodiments shown in the figures can be modified to accept electrode connectors and replaceable electrodes. For simplicity, only the modification of the embodiment of FIG. 2A and FIG. 2A ′ is shown.
Snap prong connectors are—as explained earlier—composed of a top half and a bottom half. The headgear is captured between the two halves of each snap prong connector. In FIG. 11 , three female snap prong connectors (one for each electrode) are incorporated into the headgear 100 . A frontal electrode connector 1100 is located at the center of the headgear. Two lateral electrode connectors 1102 are laterally located. A lateral wire 200 connects each lateral electrode connector 1102 to the lateral interface connector 104 . The frontal electrode connector 1100 is connected to the frontal interface connector 102 by a central wire 1104 .
Suitably matching and properly sized disposable gel electrodes 1106 can now be connected to the electrode connectors on the headgear, and replaced when necessary.
The exact location and number of electrodes on the headgear depend on the purpose of the electrical stimulation. For example, if stimulation of only one brain hemisphere is required, one lateral electrode 204 and one wire 200 (and, optionally, one lateral interface connectors 104 ) can be removed. When the head of the person 106 has no hair, electrodes can also be located away from the forehead for both stimulation of underlying brain locations and EEG acquisition at the same locations.
FIG. 12 shows a minimal embodiment 1200 of the wearable dual use brain monitoring and stimulation device, having a wire connector plug 1202 and only one female snap connector 302 .
FIG. 13 shows the dual use device 1200 with one replaceable, dual use device-mounted EEG and stimulation electrode 1300 connected.
FIG. 14 shows the dual use device 1200 affixed to the person's 106 head, supported by a single-electrode, single-band headgear 1500 .
FIG. 15 and FIG. 15 ′ show outer and inner views of the single-band headgear 1500 , modified to have only one dual use headgear-mounted electrode 1502 . This embodiment can be used in conjunction with the minimal embodiment 1200 of the wearable dual use brain monitoring and stimulation device. A single lateral interface connector wire 104 is plugged into the wire connector plug 1202 of the dual use device 1200 . The dual use device 1200 is supported by the headgear 100 . Two dual use electrodes are in contact with the person's 106 forehead: the device-mounted electrode 1300 and the headgear-mounted electrode 1502 . Through these electrodes, the dual use device 1200 can perform EEG acquisition and electrical stimulation.
FIG. 16 shows an alternate embodiment of the minimal embodiment 1200 of the wearable dual use brain monitoring and stimulation device. In this embodiment, the device-mounted electrode 1300 is adhesive, and is affixed to a non-hairy portion of the head of the person 106 . The device-mounted electrode 1300 is connected to the female snap connector 302 of the dual use device 1200 by a snap electrode wire 1600 . In FIG. 16 the device-mounted electrode 1300 is located near the top of the person's 106 head, but it could also be located underneath the headgear 1500 . Similarly, the headgear-mounted electrode 1502 could be central and located at the front of the headgear. Many more additional embodiments are possible, with additional device-mounted electrodes, or additional headgear-mounted electrodes. For instance, separate EEG electrodes and stimulation electrodes could be used instead of dual-use electrodes. A right leg drive electrode could be added. The permutations of previous embodiments, such as using electrode connectors, can apply.
FIG. 17 is a flow chart of a process for stimulating the brain of a sleeping person. The process includes two wake-time steps: the headgear wearing step 1700 and the dual use EEG monitoring and stimulation device connection step 1702 . During the headgear wearing step 1700 a person wears a dual use EEG monitoring and stimulation headgear. During the dual use EEG monitoring and stimulation device connection step 1702 the person connects a dual use EEG monitoring and stimulation device to the headgear, creating electrical connections between the dual use device and the electrodes on the headgear.
The process also includes the following sleep-time phases. In the EEG analysis phase 1704 the EEG of the person is monitored for a predetermined interval, for example 10 seconds. During this phase the EEG is also analyzed so as to extract one or more features. Such features may include the fourier transform of the signal, which can be used to determine the sleep stage and the presence of frequency-specific EEG features such as sleep spindles; rapid eye movement contamination of the EEG signal, which can be used in conjunction to the fourier transform to determine whether the person is in REM sleep; and high frequency contamination of the signal, which can be caused by facial muscle tension or movement of the person and can be used to determine the degree of arousal.
In the stimulation condition detection step 1706 the acquired EEG features are used to detect a stimulation condition, such as the person entering REM sleep. The stimulation condition detection step 1706 may also include a time condition, so as to detect a stimulation condition only after the person has experienced a specific sleep phase for a certain amount of time. For instance, if a certain type of stimulation is to be carried out during REM sleep, it would be advisable for the stimulation to be started only after enough time has elapsed so as to allow multiple consecutive REM sleep detections. The stimulation condition detection could also be limited to a certain interval of time; for example one may wish to prevent stimulation during the first hours of sleep, and only detect a stimulation condition after a certain amount of time has elapsed. Or, one may want to restrict the stimulation condition detection to a predetermined time interval in the morning.
The stimulation condition detection step 1706 may also include a safety mechanism which prevents this step from detecting a stimulation condition if the impedance of the stimulation electrodes is too high to allow safe electrical stimulation of the person's brain. Measurement of electrode impedance can be easily carried out with the same electronic circuitry required to provide the electrical stimulation. To measure electrode impedance, a very small current of known intensity, too low to be perceived by the person, is delivered. The voltage across the electrodes is measured, and by Ohm's law the impedance is calculated.
When the stimulation condition detection step 1706 does not detect a stimulation condition, the EEG monitoring and analysis phase 1704 resumes, and another chunk of EEG data is acquired and analyzed. If the stimulation condition is detected, a stimulation phase 1708 is initiated. Termination of the stimulation phase 1708 can occur differently depending on the stimulation goal. Almost always the stimulation phase 1708 will terminate after a predetermined period of time has elapsed. One may also want to monitor the person's vital signs, such as the heart rate or breathing rate, so as to detect an unwanted harmful effect of the stimulation, and then promptly terminate the stimulation.
Once the stimulation phase 1708 has ended, the process can end as shown in FIG. 17 with no further stimulations; or, the EEG analysis phase 1704 could begin again. When the process is cyclical and multiple stimulation phases 1708 can occur, one may want to prevent excessive stimulation by means of a timeout, preventing the stimulation condition detection step 1706 from detecting a stimulation condition for a predetermined amount of time (for example, half an hour) after the previous stimulation phase 1708 .
FIG. 18 is a flow chart for an alternate embodiment of the process of FIG. 17 , the embodiment also including an electrode impedance reporting step 1800 . During the electrode impedance reporting step 1800 , the person receives a visual or auditory report from the dual use EEG monitoring and stimulation device (or a mobile device capable of interfacing with to the dual use EEG monitoring and stimulation device). The report can be a simple pass/fail report, possibly in the form of a red or green colored light delivered by an LED mounted on the dual use device, or an easily recognizable pass/fail auditory signal. Alternatively, the report can communicate a measure of the impedance of the electrodes, such as a value in ohms displayed on the screen of a mobile phone, the mobile phone wirelessly receiving impedance data from the dual use device. If the electrode impedance is too high, the user can adjust the headgear, add conductive paste under the electrodes, or add water to the electrodes if the electrodes are sponges. When the electrode impedance is sufficiently low to allow safely stimulating the brain of the person during sleep, the user receives a “pass” report, and then begins the process of falling asleep. As the person falls asleep, the process moves forward to the EEG analysis phase.
Other modifications and implementations will occur to those skilled in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the above description is not intended to limit the invention except as indicated in the following claims. | A dual purpose sleep wearable headgear for both monitoring and stimulating the brain of a sleeping person is disclosed that provides a simple to use and safe platform for wearing consumer-type dual use brain stimulation and monitoring devices during sleep. The headgear enables a user to sleep comfortably while wearing the electronics and related electrodes needed for both EEG monitoring and transcranial electrical stimulation. The headgear can accept and support a miniaturized dual use monitoring/stimulation device on the forehead or the top of the head, where the bulk of the monitoring/stimulation device will not interfere with the user's sleeping position. The headgear disclosed takes the guesswork out of electrode placement, because the electrodes are prepositioned or are easily adjustable according to a predetermined pattern of electrode placement, and are appropriately sized so as to allow comfortable transcranial stimulation without producing skin irritation, and without awakening the user. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to an industrial applicable process for the preparation of materials with nanometric dimensions and controlled shape, based on titanium dioxide. The invention also relates to a process for the preparation of titanium dioxide nanorods with anatase phase composition, which are highly suitable for applications involving photovoltaic cells, particularly Dye Sensitized Solar Cells (DSSC), photoelectrolysis cells and tandem cells for the conversion of solar energy and the production of hydrogen.
BACKGROUND OF THE INVENTION
[0002] Titanium dioxide (TiO 2 ) is one of the most important metal oxides in industrial applications, since it is used in an array of different sectors, ranging from paper production to pharmaceuticals, cosmetics, photocatalysers, photovoltaic cells, photoelectric cells, sensors, inks, coatings, coverings and plastic, and even encompassing the photocatalysis of organic pollutants. In particular, certain types of TiO 2 are especially suitable for applications involving photovoltaic cells, particularly Dye Sensitized Solar Cells (DSSC), photoelectrolysis cells and tandem cells for the conversion of solar energy and the production of hydrogen.
[0003] TiO 2 has various crystalline shape. The most common crystalline phases of TiO 2 , anatase, rutile and brookite, exhibit different chemical/physical properties, such as stability field, refraction indexes, chemical reactivities and behaviour to irradiation with electromagnetic radiation. The use and performance of TiO 2 depends greatly on its crystalline phase, on its morphology and on the dimensions of the particles, as reported, for instance, by X. Chen and S. S. Mao in J. Nanosci. Nanotechnol, 6(4), 906-925, 2006. The phase composition, the shape of the crystals and the dimensions of the particles exert an enormous influence Over the chemical/physical, mechanical, electronic, magnetic and optical properties of the end product.
[0004] In terms of their dimensions, particles with nanometric dimensions have electrical, thermal, magnetic and optical properties that differ from those of larger particles. TiO 2 particles with nanometric dimensions, particularly those with a diameter of between 1 and 20 nanometres, have properties similar to those of molecules, in that they exhibit effects of quantisation and unusual luminescence (X. Chen and S. S. Mao, Chem. Rev., 107, 2891-2959, 2007).
[0005] Anatase-phase crystalline TiO 2 is an oxide that is widely used as a photocatalyser, as a white pigment for coatings and cosmetic products, and in various types of sensors.
[0006] The most recent, and most important, uses of anatase TiO 2 with nanometric dimensions concern applications involving photovoltaic cells, particularly DSSC, photoelectrolysis cells and tandem cells for the conversion of solar energy and the production of hydrogen.
[0007] Based on studies conducted on the specific application of TiO 2 in DSSC cells (X. Chen and S. S. Mao, Chem. Rev., 107, 2891-2959, 2007 and J. Nanosci. Nanotechnol, 6(4), 906-925, 2006), it has been demonstrated that the most preferred shape is anatase crystalline nanorods.
[0008] Of late, the synthesis of controlled shape nanomaterials based on TiO 2 has become the subject of much intense research, and new synthetic methods have been developed that allow the phase composition, morphology and dimensions of the particles to be controlled (X. Chen e S. S. Mao, J. Nanosci. Nanotechnol, 6(4), 906-925, 2006).
[0009] The main methods for producing nanorods for industrial use are:
a) hydrothermal synthesis; b) solvothermal synthesis; c) sol-gel synthesis.
[0013] Hydrothermal syntheses, method a), use aqueous solutions containing titanium tetrachloride, generally in the presence of acids, inorganic salts and surfactants, at temperatures of up to 160° C. (X. Feng et al., Angew. Chem. Int. Ed., 44, 5115-5118, 2005; S. Yang and L. Gao, Chem. Lett. 34, 964-5, 2005; ibid. 34, 972-3, 2005; ibid. 34, 1044-5, 2005). Preferably, it is the rutile phase that is obtained, making these methods unsuitable for the formation of anatase.
[0014] Solvothermal synthesis, method b), (C. S. Kim et al., J. Cryst. Growth, 257, 309-15, 2003) makes it possible to obtain nanosized rods with anatase phase composition. These reactions are conducted in autoclave, mostly under anhydrous conditions, at high temperatures of around 250° C., for long periods, using an aromatic solvent, such as toluene, and in the presence of an organic acid such as oleic acid, which also functions as a surfactant. The titanium/solvent/surfactant ratio of the reagents exerts a strong influence over the dimensions of the nanorods, making it a laborious process to reach the desired result. Moreover, the requirement for prolonged thermal treatment makes this method of synthesis an expensive option.
[0015] High-temperature reactions using benzyl alcohol as a solvent, and in the absence of acidity (A. P. Caricato et al., Appl. Surf Sci. 253, 6471-6475, 2007), enable the production of particles that are mostly spherical, albeit under rather drastic reaction conditions.
[0016] Sol-gel synthesis, method c), involves the controlled hydrolysis of titanium alkoxide with water, in the presence of fatty organic acids, such as oleic acid, which serves as a surfactant and stabilising agent, and catalysts such as amine or quaternary ammonium salts (Cozzoli, P. D., Kornowski, A., Weller, H. J., J. Am. Chem. Soc., 125, 14539-14548, 2003). These reactions occur under relatively mild conditions and afford control over the dimensions of the crystalline-shape particles, but the TiO 2 particles obtained are polluted by organic products, rendering them unsuitable for certain applications. The purification of these particles requires, therefore, a prolonged post-treatment calcination process, which, in addition to being costly, could significantly modify the characteristics of the end product, which may not match the requested characteristics.
[0017] R. Parra et al., in Chem. Mater, 20, 143-150, 2008, describe the combined use of organic acids with low molecular weight, such as acetic acid, and 2-propanol as a solvent, in the absence of surfactants, to produce anatase-phase TiO 2 from titanium tetraisopropoxide. However, this process makes it possible to produce only agglomerates, and not nanorods.
[0018] The patent application US 20060104894 describes the production of nanocrystals of anatase TiO 2 through the reaction of a titanium precursor and an organic acid, in the presence of an acidic catalyst (e.g. nitric acid) or a basic catalyst, in a solvent including water and alcohols with low molecular weight, heating the resultant solution to 50±15° C. However, no mention is made in this patent application of the shape of the product obtained using this process.
[0019] According to patent application US 20060034752, it is possible, through the reaction of a titanium precursor, in the presence of an acid (nitric acid, hydrochloric acid, acetic acid or oxalic acid), in water and alcohols with low molecular weight to produce a hydroxide of titanium that, only after calcination, transforms itself into TiO 2 , but does so with a mixed-phase anatase/brookite composition.
[0020] According to the patent application WO 2007028972, it is possible, through the reaction of an alkoxide of titanium in ethanol or acetone and benzyl alcohol in the presence of water or acetic acid, and only after calcination at 400° C., to produce anatase-phase TiO 2 , which is subsequently transformed into rutile-phase TiO 2 through heating to a temperature between 650° and 950° C.
[0021] Water and polyols are used in the patent application WO 2006061367, but this process is not suitable for producing anatase-phase TiO 2 nanorods.
[0022] In the patent JP 2003267705 on the production of materials coated with a metal oxide, particularly zinc oxide, where the material to be coated is immersed in the reaction mixture, reference is made to the use of acetic acid, benzyl alcohol and titanium n-butoxide as reactants, but no information is provided on the shape of the titanium dioxide obtained, which, in any case, is not isolated as such; rather, it is produced only in the form of a coating for another material.
[0023] The optimum solution for the low-cost, industrial-scale production of anatase-phase TiO 2 particles with nanometric dimensions and controlled shape, which are highly suitable for applications involving photovoltaic cells, particularly DSSC, photoelectrolysis cells and tandem cells for the conversion of solar energy and the production of hydrogen, has yet to become available. There is, then, a need for a process whereby it is possible to produce nanocrystalline, anatase-phase TiO 2 particles with controlled shape.
SUMMARY OF THE INVENTION
[0024] The present invention relates to a new process for the preparation of nanocrystalline TiO 2 particles with controlled dimensions and shape, an anatase-phase composition, through the controlled hydrolysis of a titanium precursor by means of a reaction between an alcohol and a carboxylic acid.
[0025] In one embodiment, the invention provides a process for the preparation of nanocrystalline TiO 2 particles with controlled dimensions and shape, an anatase-phase composition, and a nanorod content of >50%, comprising the reaction of a titanium precursor with an alcohol and an organic acid.
[0026] In another embodiment, the invention provides nanocrystalline particles of TiO 2 , made by the process according to the present invention, with an anatase-phase content of ≧95%, preferably ≧98%, and with control over their dimensions. The nanocrystalline TiO 2 particles made by the process according to the present invention are:
≦30 nm long, preferably ≦20 nm; ≦5 nm wide, preferably ≦4 nm.
[0029] The particles in question come predominantly in the shape of nanorods, where “predominantly” is taken to mean >50%, preferably >75%, most preferably >80%.
[0030] In another embodiment, the invention provides the use of the nanocrystalline TiO 2 particles, made by the process according to the present invention, as photocatalysers, sensors, semi-conductors, pigments, excipients and colourants.
[0031] In another embodiment, the invention provides the use of the nanocrystalline TiO 2 particles, made by the process according to the present invention, for applications in the fields of photovoltaic cells, preferably DSSC, photoelectrolysis cells and tandem cells for the conversion of solar energy and the production of hydrogen.
[0032] The present invention can be characterised as a simple, economical method that produces highly replicable results, easily to scale industrially and affords the opportunity to control the morphology and dimensions of nanometric, anatase-phase TiO 2 particles in a single step.
[0033] The product directly obtained with the process of the present invention, without recourse to any subsequent treatment, has high anatase content, nanocrystalline-scale particle dimensions and a predominant shape. The capacity to obtain TiO 2 with high anatase content, nanocrystalline-scale particles and a predominant shape in a single step also reduces production overheads. Moreover, the new method of preparation is carried out in the absence of surfactants, additional templants or other additives, thus reducing the possibility for the occurrence of a number of problems, such as unwanted reactions, phase precipitations or separations, presence of organic impurities.
BRIEF DESCRIPTION OF THE FIGURES
[0034] FIG. 1 a shown an XRPD of TiO 2 powder produced as per Example 1;
[0035] FIG. 1 b shows a TEM image of TiO 2 produced as per Example 1;
[0036] FIG. 2 a shows an XRPD of TiO 2 powder produced as per Example 2;
[0037] FIG. 2 b shows a TEM image of TiO 2 produced as per Example 2;
[0038] FIG. 3 a shows an XRPD of TiO 2 powder produced as per Example 3;
[0039] FIG. 3 b shows a TEM image of TiO 2 produced as per Example 3;
[0040] FIG. 4 a shows an XRPD of TiO 2 powder produced as per Example 4;
[0041] FIG. 4 b shows a TEM image of TiO 2 produced as per Example 4;
[0042] FIG. 5 a shows an XRPD of TiO 2 powder produced as per Example 5;
[0043] FIG. 5 b shows a TEM image of TiO 2 produced as per Example 5;
[0044] FIG. 6 a shows an XRPD of TiO 2 powder produced as per Example 6;
[0045] FIG. 6 b shows a TEM image of TiO 2 produced as per Example 6.
DETAILED DESCRIPTION OF THE INVENTION
[0046] Unless otherwise specified, all of the terms used in this application should be interpreted in accordance with their accepted meanings in common technical language. Other, more specific, definitions for certain terms used in the application are highlighted below and are intended to apply both to the description and to the claims, unless another definition, expressed in different terms, provides a wider definition.
[0047] The term “nanocrystalline” refers to products whose particles have nanometric dimensions.
[0048] The term “titanium precursor” refers to inorganic or organic compounds that contains titanium. Non-limiting examples of titanium precursor include for instance: titanium alkoxide, titanium halide, such as titanium tetrachloride, titanylsulphate, titanyl bis(acetylacetonate).
[0049] The term “titanium alkoxide” refers to the compound Ti(OR) 4 , wherein R is a C 1 -C 6 alkyl group, as defined below. Non-limiting examples of titanium alkoxide include for instance: titanium tetramethoxide, titanium tetraethoxide, titanium tetra n-propoxide, titanium tetraisopropoxide, titanium tetra n-butoxide, titanium tetra i-butoxide and the like. Particularly preferred is titanium tetraisopropoxide.
[0050] The term “alcohol” refers to an R 1 OH compound, or to mixtures of R 1 OH compounds, wherein R 1 is a linear or branched alkyl; an aryl; an aryl substituted by one or more electron donor groups, such as a C 1 -C 4 alkyl or an alkoxyl containing a C 1 -C 4 alkyl radical; an aryl substituted by one or more halogens; an arylalkyl, possibly substituted on the aryl ring by one or more electron donor groups, such as a C 1 -C 4 alkyl or an alkoxyl containing a C 1 -C 4 alkyl radical. Preferably, R 1 OH contains between 6 and 12 carbon atoms. Non-limiting examples of these alcohols include for instance: hexan-1-ol, heptan-1-ol, octan-1-ol, 2-ethylhexan-1-ol, nonan-1-ol, decan-1-ol, undecan-1-ol, dodecan-1-ol, benzyl alcohol, p-methoxybenzyl alcohol and the like, or their mixtures. Particularly preferred are benzyl alcohol, p-methoxybenzyl alcohol, octan-1-ol or 2-ethyl-hexan-1-ol.
[0051] The term “organic acid” refers to an R 2 COOH compound, or to mixtures of R 2 COOH compounds wherein R 2 is a linear or branched, saturated or unsaturated alkyl, an aryl or a heteroaryl, said R 2 group being substituted by one or more halogen, hydroxyl, alkoxyl, carboxyl, carboalkoxyl, aryl or heteraryl groups, and said acid R 2 COOH having between 1 and 18 carbon atoms. If the R 2 COOH compound contains two carboxyl groups, it is essential that they are separated from each other by at least 4 carbon atoms. Non-limiting examples of these acids include for instance: acetic acid, pivalic acid, trifluoroacetic acid, benzoic acid, phenylacetic acid, p-methoxybenzoic acid, 4-pyridylcarboxylic acid, oleic acid, adipic acid, and the like or their mixtures. Preferred acids are acetic acid, benzoic acid, oleic acid and adipic acid or their mixtures. Particularly preferred is acetic acid.
[0052] The term “C 1 -C 4 alkyl” refers to a saturated, linear or branched aliphatic hydrocarbon chain with between 1 and 4 carbon atoms. Typical alkyl groups include for instance, but are not limited: methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl and the like.
[0053] The term “C 1 -C 6 alkyl” refers to a saturated, linear or branched aliphatic hydrocarbon chain with between 1 and 6 carbon atoms, preferably between 1 and 4 carbon atoms. Typical alkyl groups include for instance, but are not limited: methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tent-butyl, n-pentyl, n-hexyl and the like.
[0054] The term “alkoxyl, containing a C 1 -C 4 alkyl radical” refers to ethers containing up to four carbon atoms. Typical alkoxyl groups include for instance, but are not limited: methoxyl, ethoxyl, iso-propoxyl, tert-butoxyl and the like.
[0055] The term “aryl” refers to an aromatic radical with between 6 and 10 carbon atoms, either with a single ring (e.g. phenyl) or with multiple condensed rings (e.g. naphthyl).
[0056] The term “heteroaryl” refers to a heterocyclic aromatic group with one or more heteroatoms in the ring, chosen from O, S or N. Typical heteroaryl groups include for instance, but are not limited: pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, thienyl, furyl, imidazolyl, pyrrolyl, oxazolyl (e.g. 1,3-oxazolyl and 1,2-oxazolyl), thiazolil (e.g. 1,2-thiazolil and 1,3-thiazolyl), pyrazolil, triazolyl (e.g. 1,2,3-triazolyl and 1,2,4-triazolyl), oxadiazolyl (e.g. 1,2,3-oxadiazolyl), thiadiazolyl (e.g. 1,3,4-thiadiazolyl), chinolyl, isochinolyl, benzothienyl, benzofuryl, indolyl, benzothiazolyl and the like.
[0057] Surprisingly, we found that the reaction of a titanium precursor with an alcohol and an organic acid, in the absence of surfactants or additional templants, makes possible to produce anatase-phase nanocrystalline TiO 2 particles, with control over the dimensions and shape of the particles.
[0058] The process of the present invention allows for the direct production of nanocrystalline TiO 2 particles with an anatase content of ≧95%, preferably ≧98%, and with control over their dimensions.
[0059] The nanocrystalline TiO 2 particles produced by means of the invention process are:
≦30 nm long, preferably ≦20 nm; ≦5 nm wide, preferably ≦4 nm.
[0062] The particles in question come predominantly in the shape of nanorods, where “predominantly” is taken to mean >50%, preferably >75% and most preferably >80%.
[0063] The nanocrystalline TiO 2 particles produced by the invention process are characterized using X-Ray Power Diffraction (XRPD) and Transmission Electron Microscopy (TEM).
[0064] In one embodiment, the invention provides a process for the preparation of nanocrystalline TiO 2 particles, with controlled dimensions and shape, an anatase phase composition and a nanorod content of >50%, comprising the reaction of a titanium precursor with an alcohol and an organic acid.
[0065] Preferably, though not exclusively, the titanium precursor is titanium alkoxide, e.g. titanium tetramethoxide, titanium tetraethoxide, titanium tetra n-propoxide, titanium tetraisopropoxide, titanium tetra n-butoxide and titanium tetra i-butoxide. Particularly preferred is titanium tetraisopropoxide.
[0066] Preferably, the alcohol should contain between 6 and 12 carbon atoms. Preferred alcohols are: hexan-1-ol, heptan-1-ol, octan-1-ol, 2-etylhexan-1-ol, nonan-1-ol, decan-1-ol, undecan-1-ol, dodecan-1-ol, benzyl alcohol, p-methoxybenzyl alcohol or their mixtures. Particularly preferred are benzyl alcohol, p-methoxybenzyl alcohol, octan-1 -ol or 2-ethyl-hexan-1-ol.
[0067] Preferably, the organic acid should contain between 1 and 18 carbon atoms. Preferred acids include: acetic acid, pivalic acid, trifluoroacetic acid, benzoic acid, phenylacetic acid, p-methoxybenzoic acid, 4-pyridylcarboxylic acid, oleic and adipic acid or their mixtures. Particularly preferred acids are: acetic acid, benzoic acid, oleic acid, adipic acid or their mixtures. Most particularly preferred is acetic acid.
[0068] The titanium precursor, the alcohol and the acid are mixed together at room temperature. The titanium precursor/alcohol molar ratios should be comprised between ⅛ and 1/20, preferably between 1/9 and 1/15, and most preferably between 1/9.5 and 1/12.
[0069] The titanium precursor/acid molar ratios should be comprised between ½ and 1/10, preferably between ⅓ and 1/7, and most preferably between 1/3.5 and ⅙.
[0070] The reaction mixture is heated, under stirring, to a temperature comprised between 80-200° C., preferably between 90-160° C., and most preferably between 90-140° C., and is then kept within that temperature range for a period comprised between 10 and 30 hours, preferably between 16 and 24 hours, in order to allow for the formation of the product with the desired characteristics.
[0071] The reaction mixture is cooled to a temperature of <80° C., preferably <50° C., and mostly preferably 25±15° C.
[0072] The processing of the reaction mixture can be carried out in one of the following ways:
a) centrifugation of the product in order to eliminate the supernatant, rinsing of the solid with appropriate organic solvents and drying in an oven, in case at low pressure; b) concentration of the reaction mixture at low pressure, dilution of the residue with an appropriate organic solvent, filtration, rinsing of the filtrate with the same solvent and drying in an oven, in case at low pressure; c) use of spray-drying or turbo-drying directly on the mixture at the end of the reaction or in case as an alternative to the drying phase used in methods a) and b).
[0076] Non limiting examples of suitable organic solvents include: alcohols, such as methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol; aliphatic ketones, such as acetone, methylethylketone, methylbutylketon, cyclohexanone; aliphatic or cycloaliphatic eters, such as tetrahydrofuran, 2-methyltetrahydrofuran, dioxane, diisopropylether, methyl t-butylether, dimethoxyethane, diethoxyethane, diethylenglycol dimethylether, diethylenglycol diethylether, triethylenglycol dimethylether, triethylenglycol diethylether; chlorinated hydrocarbons, such as dichloromethane, trichloroethylene; aliphatic esters, such as methylformate, ethylformate, methylacetate, ethylacetate, butylacetate, isobutylacetate, ethylpropionate; aliphatic or aromatic hydrocarbons, such as pentane and its mixtures, hexane and its mixtures, heptane and its mixtures, ligroine, petroleum ether, toluene, xylene; aliphatic nitriles, such as acetonitrile, propionitrile; or their mixtures in different ratios.
[0077] The nanocrystalline TiO 2 particles produced using the present invention remain stable when stored and are highly useful for a number of applications.
[0078] In another embodiment, the invention provides the use of nanocrystalline TiO 2 particles, made by the process of the present invention, as photocatalysers, sensors, semi-conductors, pigments, excipients and colourants.
[0079] In another embodiment, the invention provides the use of nanocrystalline TiO 2 , made by the process of the present invention, for applications in the fields of photovoltaic cells, preferably DSSC, photoelectrolysis cells and tandem cells for the conversion of solar energy and the production of hydrogen.
[0080] While the present invention has been described in terms of its specific embodiments, certain modifications and equivalents will be apparent to those skilled in the art and are included within the scope of the present invention.
[0081] In the following, the present invention shall be illustrated by means of some examples, which are not construed to be viewed as limiting the scope of the invention.
[0082] The following abbreviations are used below:
hr (hours); XRPD (X-Ray Power Diffraction); TEM (Transmission Electron Microscopy).
Example 1
[0084] Benzyl alcohol (403 g; 3.88 moles), acetic acid (90 g; 1.51 moles) and titanium tetraisopropoxide (106.7 g; 0.375 moles) are mixed together by mechanical stirring, at room temperature, in a 1000 ml flask equipped with a bubble condenser. The mixture is heated to the reflux temperature of around 110° C. After 5 hours, the solution becomes cloudy and tends to thicken gradually. The stirring speed is increased and the mixture left at reflux for around 24 hours. The suspension becomes fluid and displays an intense white colour. The mixture is transferred to a flask and vacuum-concentrated (0.5 mmHg) at a temperature of around 70° C. until a viscous paste is produced. The residue obtained with ethanol, and subsequently with diisopropyl ether, is then filtered and dried at low pressure, yielding TiO 2 (26.5 g), characterized by XRPD ( FIG. 1 a ) and TEM ( FIG. 1 b ).
Example 2
[0085] Following the same procedure of Example 1, but using benzoic acid (184 g, 1.51 moles) rather than acetic acid, TiO 2 is produced, characterized by XRPD ( FIG. 2 a ) and TEM ( FIG. 2 b ).
Example 3
[0086] Following the same procedure of Example 1, but using oleic acid (76.26 g, 0.27 moles) rather than acetic acid, TiO 2 is produced, characterized by XRPD ( FIG. 3 a ) and TEM ( FIG. 3 b ).
Example 4
[0087] Octan-1-ol (106.8 g; 0.82 moles), acetic acid (15.6 g; 0.26 moles) and titanium tetraisopropoxide (19.3 g; 0.068 moles) are mixed together by mechanical stirring, at room temperature, in a 250 ml flask equipped with a bubble condenser. The mixture is heated to the reflux temperature of around 110-125° C. After 5 hours, the solution becomes cloudy and tends to thicken gradually. The stirring speed is increased and the mixture left at reflux for around 20 hours. The suspension becomes milky white and the powder deposits a sediment. The mixture is transferred to a flask and vacuum-concentrated (0.5 mmHg) at a temperature of around 70° C. until an off-white powder is obtained. TiO 2 is produced (5 g), characterized by XRPD ( FIG. 4 a ) and TEM ( FIG. 4 b ).
Example 5
[0088] 2-ethyl-hexan-1-ol (106.8 g; 0.82 moles), acetic acid (15.6 g; 0.26 moles), titanium tetraisopropoxide (19.3 g; 0.068 moles) are mixed together by mechanical stirring, at room temperature, in a 4-neck 250 ml flask equipped with a bubble condenser. The reaction is heated to the reflux temperature of around 115-125° C. After around 4 hours, the solution turns slightly cloudy and takes on a light blue tinge. The reaction is left at 115° C. for around 20 hours. It is then allowed to cool to room temperature. The suspension becomes milky white and the powder deposits a sediment. The mixture is transferred to a flask and vacuum-concentrated (0.5 mmHg) at a temperature of around 70° C. until a dusty, off-white powder with easily separable aggregates is obtained. TiO 2 is produced (5.1 g), characterized by XRPD ( FIG. 5 a ) and TEM ( FIG. 5 b ).
Example 6
[0089] Following the same procedure of Example 5, but using 4-methoxybenzyl alcohol (113.3 g; 0.82 moles) rather than benzyl alcohol, TiO 2 is produced, characterized by XRPD ( FIG. 6 a ) and TEM ( FIG. 6 b ). | The present invention relates to an industrial applicable process for the preparation of materials with nanometric dimensions and controlled shape, based on titanium dioxide. The invention also relates to a process for the preparation of titanium dioxide nanorods with anatase phase composition, which are highly suitable for applications involving photovoltaic cells, particularly Dye Sensitized Solar Cells (DSSC), photoelectrolysis cells and tandem cells for the conversion of solar energy and the production of hydrogen. | 2 |
This is a continuation-in-part of our copending application filed Aug. 3, 1981, Ser. No. 289,724, assigned to the assignee of this application which is abandoned.
BACKGROUND OF THE INVENTION
The present invention relates generally to valves for high pressure hydraulic systems and in particular to fast-acting solenoid valves for use with hydraulically actuated control elements for a steam turbine.
The final control element in a steam turbine control system is generally a plurality of very large, hydraulically positioned valves through which steam flows into the turbine. For example, the steam admission control valves are preferably positioned hydraulically in accordance with a control signal which directs a servo valve to increase or decrease hydraulic pressure on the valve control mechanism. In addition to the normal valve positioning means, it is usual and prudent to also provide auxiliary valving in the hydraulic system so that the steam valves can be very rapidly closed by a trip signal in the event there is loss of load or some similar malfunction which demands a rapid shutoff of the steam flow to the turbine. Rapid closure of the steam valves is carried out in these situations by providing for a quick dump of the hydraulic fluid which sustains the steam valve position. A fast acting solenoid valve is incorporated in the trip system to facilitate the tripping action and is used to initiate the turbine trip in certain instances. It is apparent that the fast acting solenoid valve must perform reliably if the turbine is to be protected in those situations requiring a trip of the steam valves.
In the past, fast acting solenoid valves for performing this particular turbine control function have suffered from a number of drawbacks which have detracted from their reliability. Chief among these are failures to respond to a trip signal because of jammed or stuck parts and failure to pick up under marginally low voltage conditions. In addition, certain fast acting solenoid valves have created pressure transients which are reflected back into the hydraulic system during operation and which have been of sufficient magnitude to disturb other components of the hydraulic system. In general it has also been necessary to protect these valves from the effects of contaminants which might otherwise buildup in the poppet area of the valve.
Furthermore, such sealing of the poppet allows for relatively large clearances, between the poppet and the bore minimizing the chance of jamming due to misalignment or sticking. The surface area exposed to hydraulic pressure at the end of the poppet at the switched actuation chamber end is greater than the corresponding area at the opposing end with the poppet in the normal position, so that, with equal pressure in the chambers, the hydraulic forces are unbalanced and the poppet is held firmly in the first valving position.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter regarded as the invention, the invention will be better understood from the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a longitudinal sectional view, with a portion shown in cutaway, of a preferred valve embodiment illustrating the valve in its normal or reset position and showing, by dashed lines, fluid passageways interconnecting the various valve ports; and
FIG. 2 is a similar view of the valve of FIG. 1 and illustrates the valve in its energized, or trip position.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawing FIGS. 1 and 2, a two-stage hydraulic solenoid valve according to the invention and generally designated at 10 includes a valve body 12 having an inlet, or pressure port, P for making connection to a source of hydraulic fluid under pressure; an outlet port A for making connection to hydraulically controlled mechanism (e.g., a mechanism for positioning a steam valve for a steam turbine); and a drain port D for making connection to a low pressure fluid receiver or return line to the fluid source. Running longitudinally through the valve body 12 is a central opening 14 which is of various diameters at different points along its length and which defines, at one point, an integral, tapered valve seat 16. A common passageway 15 is part of central opening 14, as is cavity 19. A first portion 17 of passageway 15 extends outwardly to the left of cavity 19 and a second portion 21 of passageway 15 extends outwardly to the right of cavity 19 as illustrated in FIG. 1. As shown, cavity 19 is relatively larger than common passageway 15. Valve seat 16 is located at the juncture of portion 17 of the common passageway and cavity 19. Passageways 18, 20, and 22 in the body 12 interconnect the various valve ports A, P, and D, respectively, with the central opening 14 at separate points along its length. It will be convenient at times herein to refer to the interconnection of ports A, P, and D and the central opening 14 as the primary hydraulic circuit.
Disposed within the central opening 14 is an elongated poppet 24 which is freely traversable over short longitudinal distances between first and second valving positions as will hereinafter be more fully described. The poppet 24, shown in FIG. 1 in its normal or reset position and in FIG. 2 in its energized or trip position, is provided with first and second integral, tapered seating surfaces 26 and 27, respectively. The first and second valving positions of the poppet 24 correspond, for example, to the reset and trip conditions of a steam turbine. As illustrated, the poppet has a relatively large midsection 23 which tapers down into seating surfaces 26 and 27 and then into two smaller core sections 25 and 31 on either side of the midsection, and further into two rod sections 37 and 39.
The poppet 24 further includes sealing sections 28 and 29 at opposite ends thereof which are provided with circumferential grooves 30 and 32, respectively. Each groove 30 and 32 is fitted with a pair of seal rings 33 and 34, and 35 and 36, respectively, to prevent hydraulic fluid leakage around the poppet ends. These end seal rings 33, 34, 35, and 36 are more fully described hereinbelow. A fluid passageway 38 through a portion of the poppet 24 opens at one end 40 thereof (herein the second poppet end) and has a traverse portion 42 opening at two sides of the poppet 24 in the vicinity of the passageway 20 to the inlet port P so that fluid communication is maintained between the inlet port P and the second end 40 of the poppet 24 regardless of its position.
Inserted into the central opening 14 at the right end of valve body 12 is a guide and valve seal member 44 which includes a central bore 45 for guiding one end of the poppet and a tapered valve seating surface 46 which mates with the sealing surface 27 as shown in FIG. 2. Central bore 45 is part of portion 21 of the common passageway and seating surface 46 is at the juncture of that portion and cavity 19 as shown in both the Figures. The guide and seal member 44, sealed in the valve body 12 by O-rings 47, is shaped to provide an annular chamber 48 which is in fluid communication with passageway 20 to the inlet port P and, through holes 49 in member 44, with the central opening 14 around a portion of the poppet 24.
The guide and valve seat member 44 is held in place by an integral shoulder 50 mated to the valve body 12 and by an end cap 51 which is pulled up to the valve body by bolts 52. A cavity 54 within the end cap 51 houses a compressed spring 56 which is coupled to the poppet through spring seat 59. Thus, the spring 56 urges the poppet 24 toward its first valving position. The end cap 51 includes an extending portion 57 bearing upon the end of the guide and valve seat member 44 to hold member 44 firmly in place. An O-ring seal 58 prevents leakage of fluid from around the end cap 51. At this point it will be noted that, with the poppet 24 in the reset position as shown in FIG. 1, the inlet port P is in fluid communication with the outlet port A via passageways 18 and 20 and through the open area around valve seat 46. It will also be noted that the drain port D is fluidly isolated from the other two ports by the contact between sealing surfaces 26 and valve seat 16. In the second valving position shown in FIG. 2, the outlet port A is fluidly connected to the drain port D via passageways 18 and 22 and through the open area around valve seat 16. Simultaneously, the inlet port P is fluidly isolated from the other ports by the seal between valve seat 46 and poppet surface 27.
In order to operate the poppet 24 between its first and second valving positions, a second valve stage is provided which comprises a secondary hydraulic circuit and a solenoid actuated valve (the valving portion of which is generally indicated at 60) for directing hydraulic fluid to position the poppet 24.
Valve 60 is housed in an end portion of the central opening 14 of the valve body 12 and includes a slotted disk 62 with a center bore 63 in which a ball 64 is free to move between sealing engagements with oppositely placed third and fourth valve seats 66 and 68, respectively. In the reset position as shown in FIG. 1, a fluid path through the valve 60 is established between the inlet port P (via passageway 38, fourth valve seat 68, and the slots of slotted disk 62) and upper passageway 70. Since the poppet 24 is at least partially actuated by unbalanced hydraulic forces acting at its opposite ends, it will be observed that valve 60, in its reset position, interconnects a first actuation chamber 72 (defined as the hydraulic fluid containment volume at the first end of poppet 24 outward from seal rings 35 and 36), a second actuation chamber 74 (defined as the hydraulic fluid containment volume at the left end of poppet 24 between the poppet end 40 and valve seat 68), and the inlet port P. In the trip position as shown in FIG. 2, ball 64 is moved into contact with valve seat 68 and the first actuation chamber 72 is sealed from the second actuation chamber 74 and inlet port P. However, via third valve seat 66, upper passageway 70, annulus 76, and lower passageway 78, the first actuation chamber is connected to the drain port D. Since drain port D is connected externally to a low pressure receiver, there is a release of hydraulic pressure from the first actuation chamber 72. For clarity in the Figures, certain of the passageways are illustrated schematically; however, it will be apparent to those of ordinary skill in the art how such passageways may practically be provided.
Actuation of the ball valve 60 is carried out by solenoid actuated mechanism 80 fitted into the left end of central opening 14 in valve body 12. The mechanism 80 includes a spring loaded arm 81 which extends outward to contact ball 64. The arm 81 is retained in a sliding housing 82 and is urged outward by breakdown spring 84 which is backed by pinned plug 86. Arm 81 and housing 82 are freely translatable as a unit within mounting block 87 which is provided with seal rings 88 and fluid passageway 90 to permit fluid to enter the solenoid area at the backside of block 87.
Surrounding a portion of the actuation mechanism 80 and extending outward therefrom is a solenoid 92 including a movable armature 94 which is actuated by energizing the solenoid 92. An inner solenoid housing 93 surrounds the armature 94 and is brazed to the block 87 to prevent fluid leakage. Electrical connections to the solenoid 92 are not specifically illustrated in the Figures.
Upon energizing the solenoid 92 the armature 94 is thrust into contact with sliding housing 82 causing arm 81 to drive ball 64 into contact with valve seat 68 (FIG. 2); with the solenoid deenergized, ball 64 is forced into contact with valve seat 66 and returns arm 81 to its deenergized position. The transfer of ball 64 from valve seat 68 to valve seat 66 is caused to occur by fluid pressure acting upon ball 64. The breakdown spring 84 allows the armature 94 to contact mounting block 87 thus preventing burnout in ac solenoids and increasing holding force in both dc and ac coils.
Mounting ring 96, attached to the valve body 12 by bolts (not specifically illustrated), includes integral shoulders to retain the mounting block 87 in place. Mounting block 87, in turn, has an extension portion 97 to hold valve seats 66 and 68 and disk 62 in place. The solenoid 92 is held by retainer 91 backed by nut 89.
Operation
The two stage hydraulic solenoid valve in FIGS. 1 and 2 operates as follows.
Initially, in the reset position, solenoid 92 is deenergized and ball 64 is held in sealing contact with third valve seat 66 by fluid pressure from the second actuation chamber 74 and from the input port P. This allows pressure on the first and second actuation chambers 72 and 74, respectively, to equalize to the pressure applied at inlet port P since the two chambers are connected through ball valve 60 and to the inlet port P through passageway 38. Spring 56 initially forces the poppet 24 into contact with first valve seat 16. Once closed, however, additional force on the poppet 24 is provided by the hydraulic fluid acting on the larger surface area of poppet 24, transverse to its longitudinal axis, at the right end of the poppet 24. That is, when seated, there is an unbalanced hydraulic force on the poppet 24 adding to the force of spring 56. Thus, with the poppet seated on valve seat 16, fluid communication is established to the primary hydraulic circuit between the inlet port P and the outlet port A. Therefore any control system mechanism connected to the outlet port A receives full hydraulic pressure. As illustrated in FIG. 1 when the poppet is in its first valving position, core section 25 is insertable within portion 17 of common passageway 15 thereby establishing a clearance between that core section and the walls of body 12 which define the passageway. Fluid communication is permitted between the outlet port A and inlet port P due to the poppet's smaller rod section 39.
Upon energizing the solenoid 92 (which may, for example, be in response to a turbine trip signal), the armature 94 drives arm 81 forward, causing ball 64 to move into sealing contact with fourth valve seat 68 and releasing the seal at third valve seal 66. The first actuation chamber 72 is thus connected to the drain port D via upper passageway 70, valve 60, annulus 76, and lower passageway 78. With the release in hydraulic pressure from the first actuation chamber 72 there is a very large unbalanced hydraulic force on the poppet 24 to drive it firmly to its second valving position. This force occurs as a result of maintaining fully hydraulic pressure in the second actuation chamber 74 by way of passageway 38 back to inlet port P. Second valve seat 46 is closed and the inlet port P is isolated. The outlet port A, however, is connected to the drain port D through the open valve seat 16 and hydraulic pressure is rapidly released from any control mechanism connected to the outlet port A. As illustrated in FIG. 2 when the poppet is in its second valving position, core section 31 is insertable within portion 21 of common passageway 15 thereby establishing a clearance between that core section and the passageway. Fluid communication between the drain and the outlet port is permitted due to the smaller size of the poppet at rod section 25.
The valve is again reset by deenergizing the solenoid 92 thus allowing valve 60 to be repositioned and causing pressure equalization at both ends of the poppet in the actuation chambers 72 and 74. Spring 56 returns the poppet 24 to the first valving position where it is then held firmly by hydraulic pressure in addition to the force on spring 56.
In order to manually actuate the 2-stage valve 10 (to test the valve or to simulate a turbine trip) a spring-return push button 98 is provided outboard of the solenoid 92 at the left end of the valve 10. A compression spring 100 around center post 102 maintains the push button in its normal position. Upon being manually depressed, the spring 100 is further compressed while center post 102 forces the armature outward into the energized position. Releasing the push button 98 allows the spring 100 to return the push button and armature 94 to their previous positions and the valve 10 to return to the reset position.
Whenever the poppet 24 is caused to shift its valving position, the double seal rings 33 and 34, and 35 and 36 provide a wiping action to clean areas of the opening 14 with which they are in contact. Preferably, the inner rings 33 and 35 are of an elastomeric material and the outer slip rings 34 and 36 are of Teflon composition. This double ring construction aids the wiping and cleaning action to avoid the buildup of contaminants and permits construction without closely fitting parts which minimizes chances of the poppet sticking. In laboratory tests of a valve as disclosed herein, there has been a significant reduction in pressure transients as compared with previously used, commercially available valves. These pressure transients are particularly evident when the fluid from the inlet port is released into the drain port. Such transients may trip other valves hydraulically connected via the inlet port to this particular valve. The longitudinal span of the poppet, as illustrated herein, across midsection 23 and core sections 25 and 31 exceeds both the span of cavity 19 and the span between first and second portions, 17 and 21, respectively, of the common passageway 15. Hence, at least one of the core sections substantially maintains its respective clearance in its corresponding portion of the common passageway irrespective of the poppet's position in the valve or the common passageway. Since a clearance is always maintained in at least one passageway, the poppet core sections 25 and 31 adequately block fluid communication between the inlet and drain ports, even during the transition between its first and second valving positions such that pressure transients in the associated hydraulic system are limited. As is well known in the art, the flow through a bore which has a loosely fitted, solid cylinder inserted in the bore is primarily affected by the cube of the cylinder's radius. Therefore, to limit pressure transients in the associated hydraulic system, one must choose a clearance in the aforementioned valve which will adequately block the flow to the critical elements in the balance of the hydraulic system during the traversal of the poppet across cavity 19. The illustrated valve herein adequately blocks the flow during the poppet's valving action and limits the pressure transients in this fashion.
While there has been shown and described what is considered a preferred embodiment of the invention, it is understood that various other modifications may be made therein. It is intended to claim all such modifications which fall within the true spirit and scope of the present invention. | A two-stage hydraulic solenoid valve for controlling the application or release of hydraulic pressure to components of a steam turbine control system. The valve includes a primary hydraulic circuit in which a floating poppet operates between first and second valving positions to connect the valve's outlet port to either an inlet port or a drain port so that the connected control system components receive full hydraulic pressure or are provided with a pressure release path. A secondary hydraulic circuit controls the poppet position through a solenoid actuatable ball and valve seating arrangement wherein a ball is alternatively positioned between a pair of valve seats to switch fluid connections to poppet actuation chambers, one such chamber being located at each end of the poppet. The ball is positioned in sealing contact with one valve seat by the solenoid and is returned to the other seat by fluid pressure upon deactivating the solenoid. A spring is provided to urge the poppet into its first valving position although unbalanced hydraulic forces add to the spring force to firmly seat the valve; the poppet is moved to its second position entirely by unbalanced hydraulic forces. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to VHS video cassette service equipment, and in particular to VHS video service jigs or cassettes that simulate selected functions of a genuine cassette in ways helpful to a VCR service technician.
2. Description of Related Art
More than thirty-five million video cassette recorders, or VCRs as they are often called, are in use in the United States, and tens of millions of other VCRs are in use in other countries throughout the world. Almost all of these units will require some sort of maintenance or service, if used for a sufficiently long time.
Videotape recording formats used in the United States include the VHS format, the Beta format and the 8 millimeter format. The VHS format is the most popular format, and VCRs for the VHS format are made by the greatest number of manufacturers. The dimensions and operation of both the Beta format and 8 millimeter format video cassette recorders are substantially different. The service cassettes of the present invention is focused upon VHS format VCRs and thus the other formats will not be discussed.
Japanese companies that actually manufacture VCRs for VHS format include NEC, Hitachi, Matsushita, Mitsubishi, Sanyo, Sony and others. Korean companies which manufacture VCRs for the VHS format include Samsung and others. Many VCRs made by these Japanese companies are sold under private labels of still other companies. The VCRs for which play the VHS format all accept a standard size tape cassette familiar to all individuals who have used or service a VHS video cassette recorder. Hundreds of millions of these cassettes have been produced and sold, many as blank tapes for home or professional recording purposes, and still many others for use with prerecorded video material from commercial sources such as Hollywood film studios and music videos. VHS tape cassettes have gained wide acceptance since they provide a convenient, rugged, tamper-resistant protective casing for the spool of 0.5 inch (1.3 cm) wide magnetic tape wound on a pair of supply and takeup reels. The magnetic tape is normally provided with a clear leader and a clear trailer, each of which are several inches in length. These clear leader and trailer portions have the same general dimensions and flexibility as the other part of the tape, but lack the magnetic recording material, such as a ferrous oxide coating, normally found on the rest of the tape. The clear leaders and trailers are substantially transparent and therefore allow light to shine therethrough, while the other portions of the tape containing magnetic recording material are substantially opaque and block a beam of light. The presence or absence of the transparent leader or trailer is detected by one of two photodiodes spaced apart from one another and located next to the tape cassette handling mechanism within a VCR unit, and are used to tell the automatic tape handling equipment of the VCR when to start and stop in the various modes of operation.
All of the VCRs produced by the various manufacturers of units for VHS format will accept the standard size VHS cassette, even though the internal mechanisms within the VCR units which interact with the cassette are designed somewhat differently from manufacturer to manufacturer. There are two principal systems which interact with the standard VHS cassette, the first being in the tape loading system which transports the tape cassette into and out of the VCR, and second being the tape handling system. To load a tape cassette, the tape loading system normally transports the tape cassette horizontally in a first direction into the VCR. and then vertically downwardly to drop the tape cassette into its operating position within the VCR. To eject a tape cassette for the VCR unit, this same system raises the tape upwardly from its operating position, and then transports it horizontally in a second direction opposite the first direction.
The tape handling system, interacts with the videotape in order to perform the usual set of functions provided on most VCR units. These functions include fast forward, fast reverse, play, record, pause and stop. Several different fairly complex movements are carried out by the tape handling system in order to accomplish the foregoing functions. In particular, a portion of the tape is extracted by a pair of movable guide roller assemblies from the tape cassette when in its normal operating position. The extracted tape is wrapped in an extended arc about the circular recording drum in the play and record modes, and retracted from that position in the normal rewind sequence executed as part of the stop mode.
In order to perform a routine maintenance or other service upon the cassette transport system or the tape handling system of a VCR unit, the cover of the VCR is removed to expose these components. Then a cassette tape is inserted into the tape transport system and lowered into position, while the technician servicing the unit watches the operation of the internal components of the cassette transport system and the tape handling system. In this manner, the technician is at times able to observe or deduce the point in the operating cycle of either of these systems where some abnormality is occurring. Armed with that information, the technician can sometimes ascertain the cause or origin of the malfunction with the unit. Thereafter, the tape cassette is removed and the necessary adjustments are made. A tape cassette is once again inserted and the accuracy of the adjustments and replaced parts are then reviewed by putting the VCR unit through its paces to see whether it performs all of its functions within the tolerances set by the manufacturer's specifications.
The presence of the tape cassette within the tape transport system and/or the tape handling system obscures the technician's view of the movements and operation of a number of key components of the two systems. Thus, the technician is not always able to determine at what portion of a given cycle the conventional tape transport system or tape handling system is malfunctioning, but instead, must guess based upon the evidence before him. Also, in almost all of the VCR units, there are a number of mechanical and/or electronic alignments or adjustments which cannot be made when the tape cassette is in place in the transport system or in the tape handling system. This represents a shortcoming in the ability to efficiently, easily and reliably service VCRs in the home or at the service technician's shop.
Crestwood Products, Inc., of Des Plaines, Ill. recognized this shortcoming and offers to the VCR service trade a service cassette intended to help overcome these problems. This Crestwood Products tool is also called a VHS view-through diagnostic tool or jig that allows the operation of a VCR unit as if there were a regular cassette tape in it. In other words, the view-through tool does not include a magnetic cassette tape but instead is a plastic-injection molded frame reportedly having the same length and width as a regular VHS cassette. The unit is made of transparent plastic material, which allows the technician to see through portions of the frame and thereby determine what is going on underneath the area where a normal cassette would be positioned by the tape cassette loading system. The view-through tool includes a central member that is parallel to the left and right end walls, and is attached to the front and rear walls of the unit. The two halves enclosed by the end walls and central wall is open, except for plastic plates which contact the "cassette present" switches at the bottom of travel in the tape transport system.
In spite of its usefulness, the Crestwood service jig still has a number of drawbacks. The rear wall and central member of its frame impedes access by the technician to some components of the tape handling mechanism. Further, even though the Crestwood service jig is made of transparent plastic material, it still obscures the ability of the technician to observe components lying adjacent to it, on account of the reflective properties of the plastic and the fact that the edges do not appear to be transparent. Further, these rear wall portions and central wall portions block access to the components, as do the plates which actuate the contact switches that extend across the entire length of the bottom front of the service jig. Also, the Crestwood service cassette cannot be used with a number of newer VCR models, on account of the different mechanism used to open the tape cassette access door. Specifically, some newer VCR models made by Matsushita feature a compound-motion lever or actuator mechanism to flip open the access door of a conventional VHS tape cassette as the cassette transport system advances and lowers the VHS cassette into its operating position within the unit. Such door opening mechanisms normally require that the cassette and its access door go through a predetermined pattern of movement and the door provide a predetermined range of resistance which signifies that the door has been successfully contacted and is being flipped open. The Crestwood service jig has no provision for simulating this door opening function, and accordingly cannot be used to service these later Matsushita VHS models. Further, the lip in the front center of the Crestwood jig does not successfully operate all models of the top mechanical "cassette inserted" switch found in such VCR models as the Sharp and the Samsung VHS units.
In light of the foregoing limitations of the Crestwood Products service jig and in order to advance the state of the art for servicing VHS VCRs, it is an object of the present invention to provide a service jig which is easy to use and works safely with virtually all makes and models of VHS VCRs, including the newer models made by Matsushita, and allows such VCRs to be placed in any normal mode of operation. Newer models made by Matsushita are sold under the labels of other companies including Panasonic, Quasar, GE, RCA, Sylvania, Magnavox, Philco, Philips (USA) and Technics.
It is a related object of the present invention to provide a service jig with a entirely open tape loop area, which still simulates the placement of a normal video cassette into the VCR.
It is yet another object of the present invention to provide a service jig which safely operates the top "cassette inserted" switch of all of the VCR units which have them.
It is a further object of the present invention to provide a service jig with a compact, reliable mechanism that simulates the operation of a front cover of a tape cassette flipping over upon being advanced and lowered into operating position within a VCR unit.
SUMMARY OF THE INVENTION
In light of the foregoing problems and in order to fulfill one or more of the foregoing objects, there is provided, in accordance with the first aspect of the present invention a service jig for simulating the presence of a conventional VHS videotape cassette within a video cassette recorder designed to record or play such VHS cassettes. The service jig comprises: an E-shaped structure having an elongated common wall portion with first and second end regions and a central region located midway between the first and second end regions; first and second end wall portions respectively connected to the first and second end regions of a common wall portion; and a central arm portion extending from the central region of the common wall portion. The overall length, width and height of the E-shape structure is substantially equal to the overall length, width and height of a conventional VHS videotape cassette. The service jig or cassette of the present invention preferably includes means for simulating the resistance provided by and relative motion associated with properly opening a conventional pivotally mounted access or cover door on a VHS tape cassette for use in a VCR having lever means for engaging and flipping open such cover doors. The engagement and flipping of the cover door is accomplished upon insertion of the conventional VHS video cassette into such a videotape cassette recorder.
According to a second aspect of the invention, there is provided a service cassette or service jig that, when inserted into a conventional video cassette recorder ("VCR"), simulates the presence of a conventional VHS tape cassette, and thereby allows a service technician to put the VCR into any one of its normal operating modes and readily observe the internal operation of the VCR's tape cassette loading and tape handling systems that are normally obscured by conventional video cassette containing magnetic recording tape. This service jig comprises a substantially open structure having an elongated common member and two elongated end arm members that each extend perpendicularly from and are rigidly connected to the common member. The open structure also includes a central arm member that extends outwardly from, parallel to and is substantially equidistant from the end arm members. The structure and its members are arranged to provide a substantially open area that extends between the distal ends of the end arm members and underneath a distal end of the central arm member. This open area allows almost completely unobstructed access to the tape loop area of a tape handling system of the VCR even when the service jig is in the normal operating position for a VHS tape cassette of the VCR. This service jig preferably includes means, on the distal unsupported ends of each of the two end arm members, for blocking the transmission of a conventional directed light beams used in all conventional video cassette recorders to detect the presence or absence of opaque magnetic recording tape within a conventional VHS videotape cassette.
In accordance with a third aspect of the present invention, there is provided a service jig for simulating the presence of a conventional VHS tape cassette in a VCR to thereby allow a service technician to put the VCR in one or more operating modes and observe the operation of mechanisms internal to the VCR that are normally obscured by a conventional video cassette containing magnetic recording tape. This service jig comprises a frame structure having at least a common member and two end members that each extend perpendicularly from and are rigidly connected to the end regions of the common member. The structure is provided with at least one substantially open area between the end arm members that allows significant access to the tape handling system of the VCR even when the service jig is in the normal operating position for a VHS tape cassette of the VCR. The service jig also includes means for simulating the resistance provided by and relative motion associated with properly opening a conventional pivotally mounted cover door on the video cassette recorder in a VCR that has actuator means for engaging and flipping open such a cover door upon insertion of a conventional VHS video cassette into the VCR and the transporting of such a cassette to its normal operating position within the VCR. This means for simulating may constitute a protruding block of relatively hard material having at least one predetermined curved surface for guiding the means for engaging and flipping in essentially the same manner as a conventional VHS tape cassette having a conventional pivotally mounted access door would do. Alternatively, this means for simulating may include at the unsupported distal end of one of the arm members, a flexible strip of material arranged in a diagonal position when at rest. This strip of material will bend in response to force applied thereto by at least one lever means for engaging and opening a conventional pivotally mounted cassette door of a conventional VHS tape cassette when such cassette is used in the VCR.
These and other objects, advantages and aspects of the present invention may be further understood by referring to the detailed description, accompanying Figures, and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings form an integral part of the description of the preferred embodiments and are to be read in conjunction therewith. Like reference numerals designate the same or similar components or features in the various Figures, where:
FIG. 1 is a perspective view of a conventional VHS video cassette recorder ("VCR") shown partially broken away with the E-shaped VHS service jig of the present invention poised for insertion into the cassette handling assembly of the VCR;
FIG. 2 is an enlarged simplified perspective view of a conventional cassette handling assembly into which the VHS service jig of the present invention has been inserted;
FIGS. 2A and 2B are detail views of a first embodiment of the end of the rightmost arm of FIG. 1 service jig;
FIGS. 2C and 2D are front and side detail views of a second embodiment of the rightmost arm of the FIG. 1 service jig;
FIGS. 3 through 8 show the service jig of the present invention from different vantage points, where
FIG. 3 is a first side view,
FIG. 4 is a top view,
FIG. 5 is a second side view,
FIG. 6 is a right end view,
FIG. 7 is a left end view, and
FIG. 8 is an enlarged cross-sectional view of the central arm taken along line 8--8 of the FIG. 1 devices,
FIG. 9 is a simplified plan view of a tape cassette handling assembly of a conventional VCR with the service jig of the present invention shown in position in phantom, and the tape handling mechanisms therein shown in their retracted position; and
FIG. 10 is a diagram showing the path in a conventional VCR for VHS format magnetic tape, which shows the tape handling mechanisms of FIG. 9 in their extended or play position, and which shows the service jig of the present invention overlaid in phantom.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 there is shown a conventional VHS video cassette recorder ("VCR") 20 having a rectangular box-like cover 22 shown partially broken away to partially reveal the tape cassette loading system 24 and tape handling system 26 including recording head drum assembly 28, printed circuit board 30 and other components within the VCR. The cassette loading system 24 includes a top "cassette inserted" switch 34 mounted to a sheet metal structure 35 and other components which will be described in more detail later.
FIG. 1 also shows the service jig 40 of the present invention, as a rectangular frame structure resembling the letter "E." The service jig 40, which does not hold any videotape, has an elongated common wall portion 42, first and second end wall portions 44 and 46, and a central arm portion 48. The overall length, width and height, indicated by reference numerals 52, 54 and 56, are substantially equal to the overall length, width and height of a conventional videotape cassette. In other words, the overall length 52, width 54 and height 56 are respectively about 18.7 centimeters ("cm"), about 10.2 cm and about 2.5 cm. The service jig 40 is inserted into and through the door 36 of tape loading system 24, just like a conventional VHS cassette, as is indicated by arrows 58, and is internally handled by the VCR 20 just like a conventional video cassette.
FIG. 2 shows one conventional tape cassette loading system 24 used within a VCR 20 into which the service jig 40 has been placed. The loading system 24 includes a sheet-metal frame 70 including top member 72 (shown partially broken away) and first and second side wall members 74 and 76. The tape cassette loading system 24 also includes a movable cassette drawer or tray 78 which includes a sheet-metal frame 80 comprised of a horizontal frame member 82 and two vertical side wall members 84 and 86 located on opposite ends of horizontal member 82. The cassette loading system 24 also includes an electric drive motor 88 which may be dedicated to the tape loading system, or may be used for other purposes such as to drive the tape handling system, depending upon the particular make or model of VCR. The tape handling system 26 typically includes a gear set 90 on one or both side walls 74 and 76 of the frame 70, which may include two or more meshing gears such as drive gear 92, connecting gears 94 and 96 and arm gear 98. The tape loading system 24 may optionally include (typically only on newer models), a compound-motion lever assembly or actuator mechanism including a lever or actuator 102 which is used to engage and flip open the access door of a conventional video cassette. For example, in the recent Matsushita models, such a mechanism 100 and actuator 102 are employed.
Also shown in FIG. 2 is a preferred embodiment of the service jig 40 of the present invention sitting upon the drawer 78 when the drawer is in its fully forward position. In operation, the gear set 90, under the power provided by electric motor 88, causes the drawer 78 to advance horizontally to the position shown in FIG. 2 and then drop as shown by the dotted arrows 108 down to the phantom position indicated by the drawer frame 80' and service jig 40'.
The design and construction of the tape loading system 26 and the motion produced thereby are well known to those skilled in the art, and will not be discussed further here, except where pertinent to better explain the service jig of the present invention.
Typically, a conventional VCR includes as part of the controls for the tape handling system, a light source 120 which may include a light-emitting diode, neon bulb or other light 122, and a pair of photodetector assemblies 124 and 126, each including a photodetector such as photodiode 128. As is well known, the purpose of the light source 120 and photodetectors 124 and 126 is to determine when the spool of tape in a conventional videotape cassette is at its beginning or at its end. Two beams of light 134 and 136 emanate through light passages within a conventional video cassette, and then through apertures 138 and 140 in the side frame members 74 and 76, to the photodetectors 128.
FIG. 2 and FIGS. 2A through 2D show in further detail the design and construction of the means for simulating the resistance and relative movement provided by a pivotally mounted access door in a conventional VHS tape cassette. These means will be described in detail later.
FIGS. 3 through 8 show various views of a preferred embodiment of the service jig 40 of the present invention. FIG. 3 shows the common wall portion 42 of the jig 40, which has first and second end regions 144 and 146, and a central region 148 located midway between the first and second end regions. The shaded area 150 is where the record lock-out tab would be located on the conventional video cassette. As is well known, such a tab may be broken off to prevent recording. In the preferred embodiment of the present invention, the entire exterior surface 142 of elongated common wall portion 42 is solid, including area 150. Making area 150 solid helps ensure that when service jig 40 is placed inside a VCR, the VCR can enter in its record mode.
FIG. 4 shows the service jig 40 from the top, which reveals further details. The service jig 40 includes stationary pads 154 and 156 respectively located in the interior corners formed by the meeting of the common wall portion 42 and the end wall portions 44 and 46. The pads 154 and 156 constitute first and second means for actuating cassette-in-position switches, represented by circles 158 and 160 shown in phantom in FIG. 4, found underneath the frame 70 of the tape handling system in almost all VCRs. The switches 158 and 160 when activated, tell the VCR that a conventional video cassette has been properly lowered to the operating position by the tape handling drawer 80. In the preferred embodiment, the size of pads 154 and 160 are approximately 1 cm wide (as indicated by dimension 162) and have a length of 1 cm to 3 cm, as measured from line 163 (and as indicated by dimension 164). In other words, the pads 154 and 156 may be as small as about 1 cm square, but also may have a length which extends to the adjacent end wall as shown for further rigidity.
The common wall portion 42 may also include strengthening ribs 174 and 176, if desired, to provide additional rigidity against flexing in the direction perpendicular to the plane of exterior surface 142. As may be seen in FIG. 3, the thickness 178 of such ribs may be made identical to the contact pads 154 and 156. A suitable range of dimensions for the thickness of each of these ribs is 0.2 cm to 0.6 cm.
In FIG. 4, the first and second end wall portions 44 and 46 are shown to have a substantially uniform thickness over most of their length, which thickness as indicated by dimensions 184 and 186 may range, for example, from about 0.2 cm to about 0.5 cm. The first end arm portion 44 terminates at distal end 188 with a short wall portion 190 and a roof portion 191 extending at right angles to the rest of arm 44, as shown. The second end arm portion 46 terminates at its distal end 196 which also includes a wall portion 198 and a roof portion 199 extending at right angles to the rest of the arm 46. The overall width, that is dimension 54 shown in FIG. 1, is set by the length of arm 44 and 46. The terminal portions 190 and 198 of end arms 44 and 46 butt against stop pads of the drawer 78, such as pad 200 which may be seen in the left-hand side of FIG. 2. The roof portions 191 and 199 also contact guides or leaf springs (not shown) that extend down from the top member 72 of the frame 70, which are typically provided as part of the frame 70 in a conventional VCR. Thus, roof portions 191 and 199 serve to help ensure that service jig 40 is correctly positioned within the drawer 78 of the cassette handling system, just like a conventional video cassette.
The preferred structure of central arm portion 48 of the E-shaped service jig structure 40 may be fully understood by reference to FIGS. 3 through 5 and 8. The purpose of central arm 48 is to safely and reliably actuate any centrally-located top cassette-inserted switch, such as the switch 34 shown in FIGS. 1 and 2. The actuation of this top switch 34 is normally accomplished by the leading top edge and top planar surface of a conventional video cassette. In the service jig 40 of the present invention, this same result is achieved by a thin, substantially rigid arm 48 which has been designed so as to minimize visual and mechanical obstruction of the tape loop area, as will be further explained below. As may be seen in FIG. 4, the central arm 48 is comprised of first, second and third regions 210, 212 and 214 arranged in line with one another so that the arm 48 is perpendicular to the wall 142 of common wall portion 42. As best seen in FIG. 8, the first region 210 has upper and lower sections 216 and 218 rigidly connected to the central region 148 on the common wall portion 42, and has an intermediate support section 220 extending between the upper and lower sections 216 and 218. The lower section 218 includes a preferably rectangular orifice 222 for receiving therethrough a conventional locator post 224 rigidly connected to the chassis 226 of the VCR 20.
The second region 212 of central arm 48 is rigidly connected to and extends outwardly from the upper section 216 of the first region 210, and is configured as a single, substantially planar member which may have a rectangular cross-section. The third region 214 is rigidly connected to and extends outwardly from the second region and is the unsupported distal end of the arm 48. The third region 214 has an upwardly beveled surface 225 as shown for safely actuating the top cassette-inserted switches found in many models of VCRs as part of the tape cassette loading system 24. Region 214 need not be as thick as region 212, since such extra strength is not necessary at that point. Further, the regions 212 and 214 may be tapered so that the distal end dimension 227 is less than the base dimension 228 (see FIG. 4). Thus, section 218 is preferably comprised of two elongated members 218a and 218b which define the sides of rectangular orifice 222. If desired, the lower section 218 could be made out of a solid piece of material having a hole approximately 1 cm in diameter for the locator post 224 to project through. However, the much larger rectangular orifice 222 is preferred since it provides greater visibility and access to the area therebelow. Alternatively, to simplify manufacture by plastic injection molding techniques, the members 218a and 218b could extend upwardly all the way to upper section 216. As a further variation, the service jig of the present invention could have the arm 48 formed as a large rectangle with the vertical support 220 located near the distal end of the arm. However, this would undesirably impede visibility and access to the area beneath regions 212 and 214, which is undesirable. One of the significant benefits of the service jig 40 of the present invention is that it provides a means for reliably actuating the top cassette-inserted switch while still providing a substantially open central area 230 under the second and third portions 212 and 214 of central arm 48. This area 230 is centrally located within the tape loop area of a conventional cassette, and is an area where it is important to have maximum visibility during maintenance and repair procedures.
FIGS. 4, 5 and 6 show the construction for the end portion 196 of arm 46. The end region 196 includes a notched area 240 representing the space where one edge and a conventional pivot mechanism of a hinged access door of a conventional video cassette would be located, for those VCR units which require that such clearance be present. The exterior surface 242 of end wall 198 includes a protrusion or block of hard material 244 specially shaped to engage the lever or actuator 102 of the door-opening mechanism 100 previously described with respect to FIG. 2 As shown in FIG. 5, the block 244 is approximately 1 cm long as indicated by dimension 246 and has an average width of about 0.3 cm to 0.4 cm wide as indicated dimension 248. The thickness of block 244 is preferably about 0.2 cm to 0.3 cm as indicated by dimension 250 in FIG. 6. The block 244 has two sloping surfaces 252 and 254 upon which ride the tip 102a of lever 102 of the door-opening mechanism found in recent models of VCRs produced by Matsushita. Surface 254 is slightly bowed inwardly, so that it has a slightly concave profile, as shown. The angles 262 and 264 of the surfaces 252 and 254 respectively are approximately 30 to 45 degrees from the horizontal and approximately 20 to 35 degrees from the vertical. Angles within the foregoing ranges are believed to provide the right amount of resistance to the tip of lever 102 on a smooth plastic surface to repeatably and accurately simulate the resistance and relative motion with properly opening a conventional pivotally mounted cover door on a VHS video cassette in a conventional VCR, such as the aforementioned Matsushita models having a lever means for engaging and flipping open such cover doors upon insertion of such video cassette into such a VCR.
FIGS. 2, 2A and 2B show the beginning and ending positions 266 and 268 of the tip 102a of lever 102 as it contacts and follows along the curves 252 and 254. Initially, the cassette drawer 78 is partially advanced and the tip 102a of the lever 102 makes contact with the bottom portion of the diagonal surface 252, i.e., at location 266, indicated in FIG. 2A. Thereafter, upon further rotation of gear set 90, the cassette drawer 78 advances to the position shown in solid lines in FIG. 2 and then the drawer is lowered to the position indicated in FIG. 2B. As this occurs, the tip 102a moves upwardly along diagonal surface 252 and then along diagonal surface 254, and ultimately ends up at position 268 at the top of surface 254, as indicated in FIG. 2B. In practice, the mechanism 100 and its lever 102 are moved both in the horizontal and vertical directions by the tape loading mechanism, at least in the recent models of VCRs by Matsushita. Accordingly, it may be said that the actuator means for engaging and flipping open such a cassette cover door executes a compound motion, while the tip 102a of lever 102 moves through the path just described.
FIGS. 2C and 2D show another embodiment of the means for simulating the resistance provided by and relative motion associated with properly opening a conventional pivotally mounted covered door on a VHS videotape cassette for a conventional VCR having compound motion actuator means of the type just described. The distal end 196 of end arm 46 is the same as shown in FIGS. 2A and 2B, except that instead of the block 244, there is provided a strip of flexible material 264 configured as shown in FIGS. 2C and 2D which is inserted into and anchored by epoxy or by a complementary snug hole in the exterior face of horizontal segment 198 of the arm 46, as shown in FIG. 2D. The flexible strip 265 may be made out of spring steel, semi-rigid plastic material or other pliant material that has the capability of elastically flexing at least 20 degrees in response to forces exerted by the tip 102a of lever 102. The tip 102a begins at the lower end 266' of the flexible strip 265 and as the cassette drawer 78 drops into position, the tip 102a advances to the location 268'. The precise angle required of the flexible strip 265 is a function of its flexibility and the frictional resistance provided by its surface to the tip 102a of lever 102. In prototypes of this embodiment of the door-opening simulator of the present invention, the average angle was in the range of about 30 degrees to about 55 degrees from the vertical for a flexible strip of nylon or similarly semi-rigid plastic having an overall free length of about 1 cm, a width of about 0.2 cm, and an average thickness of about 0.05 to about 0.075 cm.
The service jig 40 of the present invention may be made from any suitably rigid material, including almost any conventional impact-resistant plastic material out of which enclosures for conventional video cassettes are made. Suitable high-strength polymeric materials include ABS, class A sheet molding materials, plastic-injection molding materials including nylon, PVC materials, and the like. The material is preferably fairly smooth and preferably is electrically nonconductive. If desired, a metallic wire frame having an E-shaped configuration may be employed, provided that the wire frame is coated or has molded thereupon a final coating of an electrically insulating smooth material.
The overall weight of the service jig 40 may be varied as desired, such as in the range from about 75 grams up to 500 grams or more. Preferably the service jig has an overall weight in the range of about 150 grams to about 400 grams, with the most preferred range being about 200 grams to about 300 grams, since this simulates the overall weight of average cassette loaded with the usual amount of videotape. If necessary, the average thickness of the walls of the common or end wall portions may be decreased or increased to achieve the desired weight.
The advantages of the service jig 40 of the present invention will now be explained with reference to FIGS. 9 and 10. FIG. 9 shows a simplified plan view of one conventional VHS tape handling system found in a conventional VCR, such as the Fisher Corporation Model ER-7(B) Series. The various components and maintenance procedures for this VCR are described in the Fisher Reference Manual No. WM-12380, available from SFS Corporation of Comption, Calif. Readers desiring further details of the mechanical construction operation of the diagram shown in FIGS. 9 and 10 should refer to this manual. FIG. 9 shows various major components found in the tape handling system 26 of a conventional VCR in their at-rest or retracted position, while FIG. 10 shows many of these same components in their extended or advanced position. The tape handling system 26 is normally mounted on its own chassis 300 and typically includes the following major assemblies: a recording head drum assembly 302 with recording/play head 303; full erase head assembly 304 with erase head 305 and audio control erase head assembly 306 (shown in FIG. 10); tape guide roller assembly 308 and pinch roller assembly 310 (also shown in FIG. 10); supply guide roller assembly 314 including roller 315 and angle pole 316 and take-up guide roller base assembly 317 arranged on either side of the recording head 302; loading base assembly 320 and tape guide assembly 322. Major mechanisms for winding up a videotape within a tape cassette in either direction and visible in FIGS. 9 and 10 include: the supply wheel assembly 330; the take-up reel assembly 332; the idler hold arm assembly 334; the tension arm/band assembly 338; the supply bracket assembly 340; the take-up bracket assembly 342 and the actuator plate assembly 344. Also, within a conventional video cassette, idler rollers 358 and 360 are provided to guide the path of the cassette tape as it is fed in forward and reverse directions.
In the normal operation of a VCR, the tape-handling components start out in the at-rest positions shown in FIG. 9. A conventional VHS video cassette when in operating position within a VCR has its supply and take-up reels engaged in complementary supply and take-up reel gears forming part of supply reel assembly 330 and take-up reel assembly 332. FIG. 10 shows in simplified form the generally rectangular outline 370 of a conventional VHS cassette having supply and take-up spools 372 and 374 which each have some magnetic tape 376 and 378 wound thereupon within the confines of circularly-shaped supply reel casement 382 and take-up reel casement 384. A loop of magnetic tape including portions 386, 388 (shown in phantom) and 390 depict how the tape starts out when the conventional cassette 370 is first placed in operating position by the cassette loading system 24. Once the VCR 20 commands the tape handling system 26 to actuate and place the loop 388 of tape in its normal operating position about the recording drum 303 of drum assembly 302, the supply guide roller 315 and angle pole 316, and the take-up guide roller 318 and angle pole 319 move from their at-rest position in the direction of arrows 394 and 396 respectively to the positions shown in FIG. 10, thereby causing the portion 388 of tape shown in phantom in FIG. 10 to wrap around the head 303 and other components as is shown by the solid lines 388.
As may be seen by FIGS. 9 and 10, the conventional combination of gears, rollers, guides and levers which make all of this happen is quite complex and the VCR is subject to malfunction if any critical component should be out of alignment or excessively worn. Thus, in order to facilitate the ability of a service technician to inspect the unit for malfunctions or test the unit for proper operation, it is very useful to allow the service technician to see as much of the mechanical action and positioning of the various components as possible, and to be able to reach them. The service jig 40 of the present invention does this to virtually the maximum extent possible, while simulating the presence of a conventional VHS videotape cassette to allow the VCR to function in all of its normal operating modes. The E-shaped service jig 40 of the present invention also provides a substantially open area for tape loop 388 between the end arm members 44 and 46 that allows significant and substantially unobstructed access to the tape handling system of the VCR even when the service jig is in a normal operating position for VHS tape cassette within the VCR. This is illustrated by the large open expanses of area between the central arm portion 48 and the end arm portions 44 and 46 shown in phantom in FIG. 9. Also, those in the art will appreciate that the area 230 underneath the second and third regions 212 and 214 of central arm 48 is also open, which allows the service technician to view any mechanisms thereunder and to insert inspection probes or adjustment tools into this area to make any necessary inspections or adjustments.
In FIG. 10, the E-shaped service jig 40 is also shown overlaid upon the outline 370 of a conventional cassette for easy reference. The light source 122 and photodetectors 128 and the light beam paths 134 and 136 are also shown for convenient reference. As may be seen in FIG. 10, the end regions 188 and 196 of the end arms 44 and 46 block the light beams 134 and 136. This occurs by making at least the end regions 188 and 196 of material which is opaque to the transmission of light at the wavelengths emitted by light source 120. When the beams are blocked, the photodetectors 128 inform the VCR circuitry that magnetic recording tape is present. Thus, when the service jig 40 is in a VCR, it may be placed in any of the operating modes, Including record, play, fast forward, fast reverse and pause. Thus, all modes of operation of the VCR may be successfully checked out by the service technician using service jig 40.
The foregoing detailed description shows that the preferred embodiments of the present invention are well suited to fulfill the objects above-stated. It is recognized that those skilled in the art may make various modifications or additions to the preferred embodiments chosen to illustrate the present invention without departing from the spirit and proper scope of the invention. As a first example, the inner surfaces of end arm portions 44 and 46 could be somewhat arcuate rather than substantially flat. As a second example, the E-shaped structure may be made of transparent plastic material with only end regions 188 and 196 being made of or covered with opaque light-blocking material. As a example, the means for simulating the opening of the cover door of a conventional video cassette may be varied, such as providing a mock door which is pivotally connected in conventional manner to the end region 196 of the end arm portion 46, but extends no further than the other side of the same arm. A very light torsion spring or leaf spring could be added if desired to this mock door to simulate the precise weight of a conventional cover door. Also, open rather than closed common wall portion and end wall or arm portions may be utilized. These surfaces could be made of a lightweight substantially open plastic-coated steel wire framework, which would still have the outline of the E-shaped structure of the service jig, so that the overall dimensions of the service jig would still be accurate, with a solid wall or face of material being placed only where needed for strength, or to interact with the operator of an electrical position switch or a locator/positioning device of the tape loading or handling systems. Accordingly, it is to be understood that the protection sought and to be afforded hereby should be deemed to extend to the subject matter defined by the appended claims, including all fair equivalents thereof. | A service jig for enabling technicians to more efficiently and easily inspect and repair VHS conventional video cassette recorders in need of service. The jig or service cassette, as it is sometimes called, is an E-shaped structure that, when inserted into a conventional VCR, simulates the presence of a conventional VHS tape cassette, thus allowing a service technician to put the VCR into any one of its normal operating modes and observe the operation of mechanisms internal to the recorder that are normally obscured by a regular cassette. The service jig is of a substantially open design which allows almost completely free access to the tape loop area of the tape handling system of the VCR. The central horizontal arm of the E-shaped structure safely actuates the top "cassette inserted" switch found a number of VCR models. The two horizontal end arms of the E-shaped structure block the light beam used in a number of VCRs to check for the presence of magnetic recording tape, so that such VCR units can be placed into play or record mode when the service jig is inserted within it in operating position. Two different mechanisms are also disclosed and used as part of the service jig for simulating the opening of the tape cover door of a conventional VHS cassette in a manner compatible with newer VCR models. | 6 |
RELATED APPLICATION
[0001] This application is a continuation of U.S. Utility patent application Ser. No. 11/273,877, entitled “ILLUMINATED MODULAR DISPLAY,” filed on Nov. 14, 2005, which application is a divisional of and claims priority to U.S. Utility patent application Ser. No. 11/022,392, entitled “MODULAR DISPLAY APPARATUS,” filed on Dec. 22, 2004. The contents of these applications are incorporated expressly by reference herein, as if fully set forth and full Paris Convention Priority is hereby expressly claimed.
BACKGROUND
[0002] The present invention relates generally to a modular display apparatus and more particularly to a modular display apparatus having a number of improved static display features, as well as interactive instructional capabilities. In an illustrative embodiment, these features are directed to the selection and application of wood treatment products.
[0003] In the past, wood treatment products such as paints, stains, water proofers, etc., have customarily been made available for purchase at various hardware, paint supply, and home supply stores. Selection of an appropriate product by the consumer has entailed reading product labels and brochures, examining various samples, and chatting with store personnel in a decentralized and often ad hoc or haphazard manner. Learning how to properly apply such products typically involves discussion with store personnel, reading often terse product labeling and trial and error.
SUMMARY
[0004] The following is a summary of various aspects and advantages realizable according to various embodiments of a modular display apparatus according to the present invention. It is provided as an introduction to assist those skilled in the art to more rapidly assimilate the detailed discussion of the invention that ensues and does not and is not intended in any way to limit the scope of the claims that are appended hereto.
[0005] With this in mind, according to one aspect of the invention, there is provided a modular display comprising a number of interchangeable modules installable adjacent one another on a shelf. The modules may be designed to conveniently present samples and brochure information. According to another inventive aspect, one of the modules may comprise an interactive video unit providing instruction as to product selection and/or application. One or more of the modules may further provide concavely curved receptacles or grooves for receiving a flat display panel and imparting a concave contour thereto. Such a panel may carry sample chips, attached, for example, by a two piece chip holder which facilitates removal or changing out of sample chips.
[0006] According to another aspect, a mechanism is provided for removably retaining the modules in place on the shelf. One embodiment of such a mechanism comprises a panel slideable into and out of position between the shelf and the modules. A front molding piece is attached to the front panel and comes into abutment with the modules to retain them in place.
[0007] A specially designed lighting fixture may further be provided to uniformly and attractively illuminate the display. The modular structure may further be provided with a sprinkler irrigation feature comprising a water flow-through system for channeling and distributing water discharged by fire sprinkler systems.
[0008] Various of the inventive aspects just discussed may be combined to provide a product selection center where a customer may conveniently and centrally access information concerning the selection and application of wood treatment products.
DRAWINGS
[0009] FIG. 1 is a perspective view of an illustrative embodiment of a display apparatus according to the invention;
[0010] FIG. 2 is a perspective view illustrating a plurality of display modules employed in the display apparatus of FIG. 1 ;
[0011] FIG. 3 is a perspective view of a first of the display modules of FIG. 2 ;
[0012] FIG. 4 is a front view of the display module of FIG. 3 ;
[0013] FIG. 5 is a side view of the display module of FIG. 3 ;
[0014] FIG. 6 is a side view of a cabinet component in which display modules employed in the apparatus of FIG. 1 may be installed;
[0015] FIG. 7 is a top view of the cabinet of FIG. 6 ;
[0016] FIG. 8 is a perspective view of a second display module for use in the display apparatus of FIG. 1 ;
[0017] FIG. 9 is a side view, of the second display module of FIG. 8 ;
[0018] FIG. 10 is a perspective view of a third display module;
[0019] FIG. 11 is a side view of the display module of FIG. 10 ;
[0020] FIG. 12 is a perspective view of a fourth display module;
[0021] FIG. 13 is a side view of the display module of FIG. 12 ;
[0022] FIG. 14 is a perspective view of a fifth display module;
[0023] FIG. 15 is a side view of the display module of FIG. 14 ;
[0024] FIG. 16 , is a front view of a display panel insertable into the fourth display module of FIG. 12 ;
[0025] FIG. 17 is a front view of the display panel of FIG. 16 with a plurality of sample chip display units mounted thereon;
[0026] FIG. 18 is a perspective view of a recessed lighting fixture of the display apparatus of FIG. 1 ;
[0027] FIG. 19 is a sectional view of the apparatus taken at 19 - 19 of FIG. 23 ;
[0028] FIG. 20 is an end view of a lamp fixture utilized in the apparatus of FIG. 18 ;
[0029] FIG. 21 is a top view of the lighting fixture of FIG. 18 ;
[0030] FIG. 22 is a side view of the fixture of FIG. 18 ;
[0031] FIG. 23 is a sectional view of the fixture of FIG. 18 taken at 23 - 23 ;
[0032] FIG. 23 a is a top view of a diffuser component employed in connection with the light fixture of FIG. 18 ;
[0033] FIG. 23 b is an enlarged view of a fragment of the diffuser of FIG. 23 a;
[0034] FIG. 24 is a perspective view of components of the display apparatus of FIG. 1 illustrating a water flow through feature;
[0035] FIG. 25 is a rear perspective view of the apparatus of FIG. 24 ;
[0036] FIG. 26 is a perspective view of an interactive video module of the apparatus of FIG. 1 ;
[0037] FIG. 27 is a perspective view of a portion of the interactive video apparatus of FIG. 26 further illustrating a removable paint chip display panel;
[0038] FIG. 28 is a perspective view illustrating an apparatus for securing the display modules of the display apparatus of FIG. 1 in position;
[0039] FIG. 29 is an enlarged perspective view of a portion of the apparatus of FIG. 28 ;
[0040] FIG. 30 is a perspective of a portion of the apparatus of FIG. 28 illustrating the installed position;
[0041] FIG. 31 is a fragmentary view further illustrating an alternate method and an apparatus for securing display modules of the display apparatus in position;
[0042] FIG. 32 is a fragmentary view of a portion of the display panel of the display 11 of FIG. 1 illustrating a particular embodiment of a wood chip mounting mechanism;
[0043] FIG. 33 is a perspective view of a chip clip mounting mechanism in disassembled relation;
[0044] FIG. 34 is a perspective view of a removable chip holder component of the chip mounting; and
[0045] FIG. 35 through 37 are sectional views illustrating the sequential assembly and installation of a chip mounting mechanism.
DETAILED DESCRIPTION
[0046] A display apparatus 11 according to an illustrative embodiment is shown FIG. 1 . The apparatus 11 includes a cabinet 13 which mounts 5 display modules, 17 , 19 , 21 , 23 , 25 . In the illustrated embodiment, the modules 17 , 19 , 21 , 23 , 25 separately mount into the cabinet 11 and therefore are subject to being reordered in any desired sequence.
[0047] The first and fifth display modules 17 , 25 comprise brochure display modules. The first display module 17 presents brochures of a first size, while the fifth display module displays brochures of a second size. The size, of course, could be the same or different, as desired.
[0048] The second and fourth display modules 19 , 23 , mount respective concave display panels 27 , 28 . The first display panel of 27 may provide a display of a plurality of wood chips to each of which has been applied a different water proofing coating. The second display panel 28 may present a display of a plurality of wood chips each stained with a different wood stain, which may be, for example, either a solid and/or semi-transparent stain.
[0049] The third display module 21 includes an interactive instructive video display 29 , which may comprise a DVD/DVI ( 143 , FIG. 26 ) player. The module 21 further mounts a display panel 31 . The display panel 31 preferably mounts a plurality of adjacently disposed wood chips. Each of the chips comprises a different species of wood to which the same wood stain product has been applied. In this manner, a potential customer may appreciate the difference in overall appearance contributed by the underlying wood species.
[0050] A recessed fluorescent lighting fixture 27 is disposed above the display modules 17 , 19 , 21 , 23 , 25 . As will be explained in more detail below, the recessed lighting fixture 27 is specially designed to provide optimum and uniform illumination of the samples displayed by the display panels 27 , 28 .
[0051] FIG. 2 illustrates the display apparatus 11 and the modules 17 , 19 , 21 , 23 , 25 with various graphic display components removed. Each of these components 11 , 17 , 19 , 21 , 23 , 25 of FIG. 2 will be now described in more detail.
[0052] FIGS. 3 thru 5 illustrate the construction of the large brochure module 25 . This module 25 includes first and second side panels, 33 , each of which has a bottom edge 39 and back edge 38 , which meet at right angles to one another. The front edge of each panel 33 is defined by a first vertical linear section 30 , which meets with a convexly curved section 36 , which then leads to a second vertical depending section 32 . The vertical section 32 forms into a surface whose top edge 132 is disposed at a slightly acute angle to the horizontal. Thus, a vertical leg 34 and a horizontal foot 37 are defined on each of the side panels 33 . The side panels 33 are linked to one another by a back panel 35 , a floor or base panel 47 , and an upper horizontal panel 44 . The module 25 further includes a central panel 45 having a convex outer edge 46 , which lies in parallel with the respective convex edges 36 of the side panels 33 . A hole 26 is formed in the floor panel 47 through which a fastening device such as a screw may be inserted to fasten or attach the module 25 to an underlying shelf or other structure.
[0053] Respective deck panels 41 , 42 are disposed between the first side panel 33 and the central panel 45 and between the central panel 45 and the second side panel 33 , respectively. Clear vertical face panels 46 , 48 are further mounted in slots in the respective side and central panels 33 , 45 . The face panels 46 , 48 may comprise, for example, plexi-glass preferably anchored in place by a suitable adhesive. The panels 33 , 35 , 47 , 45 of the module 25 are preferably made of suitable wood or wood substitute materials fastened together according to conventional means well-known to those skilled in the woodworking arts.
[0054] FIGS. 6 and 7 further illustrate the cabinet 13 , which mounts the five modules 17 , 19 , 21 , 23 , 25 . As shown, the cabinet 13 preferably includes identical rectangular vertically disposed end panels 51 , 53 , between which are mounted a horizontal rectangular base “shelf” 56 and a vertical rectangular back panel 55 . The back panel 55 is inset from the back edge 58 of the base 56 . Holes 57 are bored through base portion or shelf 56 behind the back panel 55 to facilitate water flow according to a fire prevention irrigation feature described in more detail hereafter.
[0055] FIGS. 8 and 9 further illustrate the third display module 21 , which mounts the video monitor 29 ( FIG. 1 ). The module 21 includes first and second rectangular vertical side panels 61 , 63 spaced apart by a width appropriate to mount the video monitor 29 . The side panels 61 , 63 further include horizontally extending display card mounting portions 67 , 69 in which are formed suitably curved grooves 75 for receiving a display card as described in further, detail hereafter. The module 21 further preferably includes a horizontally disposed rib 73 , which provides a support structure to horizontally stabilize the module 21 . Again, the module 21 may be fabricated of suitable wood or wood substitutes according to techniques well-known to those in the woodworking arts.
[0056] FIGS. 10 and 11 illustrate the fourth display module 23 in more detail. The fourth module 23 includes a rectangular base member 73 , a vertical rectangular back panel 71 and respective vertical side panels 75 , 77 . The side panels 75 , 77 each have a horizontal bottom edge 76 and a vertical back edge 78 . Each of the display panels 75 , 77 further has a concave outer edge 80 , 82 and an interior concave groove, e.g., 84 , for receiving the display panel 28 . The respective interior grooves, e.g., 84 , are mirror images of and lie parallel to one another.
[0057] The fourth display module 23 further includes first and second interior support panels 79 , 81 , each of which has a respective horizontal bottom edge, vertical back edge, and a concave surface 68 , 69 . The concave surfaces 68 , 69 are parallel to one another and disposed in line with the grooves 84 so as to provide support to the display panel 28 , after it has been inserted into the grooves 84 , as described in more detail below. Finally, the bottom panel 73 of the module 23 includes a number of water drainage holes 86 . These holes cooperate with the fire sprinkler water distribution system to be described in further detail below.
[0058] FIGS. 12 and 13 illustrate the second display card holding module 19 in more detail. The module 19 includes first and second vertically disposed side panels 91 , 93 , each of which has a vertical back edge 94 and a horizontal bottom edge. 95 . Each of the side panels 91 , 93 further includes a concave outer edge 97 , 99 . Each interior side surface of each of the side panels 91 , 93 includes a concave groove, e.g., 101 . The grooves 101 are again mirror images of and disposed parallel to one another. The second display module 19 further includes a vertical, rectangular back panel 90 and a horizontal rectangular base panel 92 . Again, suitable drainage holes 106 are created in the bottom panel 92 .
[0059] FIGS. 14 and 15 illustrate the first display module 17 in more detail. The first display module 17 includes first and second side panels 101 , 103 contoured similarly to those of the display module 25 of FIGS. 3-5 . Like module 25 , the module 17 includes a horizontal rectangular base panel 105 and vertical rectangular back panel 107 . The module 17 further includes a plurality of rectangular horizontal deck members 109 , 111 , 113 , disposed in step-like fashion with respect to one another. The module 17 further includes a number of vertical transparent face plates 115 , 117 , 119 , 120 , which may be, for example, disposed in suitable grooves in the side panels 101 , 103 and retained in place by a suitable adhesive. A hole 29 is formed in the base panel 105 through which a fastening device such as a screw may be inserted to attach the module 17 to an underlying shelf or other structure.
[0060] FIGS. 16 and 17 show an illustrative embodiment for a display panel 28 ( FIG. 1 ) for insertion into the fourth display module 23 . The panel 28 shown in FIG. 15 may comprise, for example, a rectangular panel of 0.125 millimeter thick expanded PVC. Illustrative dimensions of such a panel are 825.5 millimeters (32.5 inches) in width (w) and 590.55 millimeters (23.250 inches) in height (h). As further illustrated, suitable holes 113 , which may be for example 166 in number, are punched or otherwise created in the panel 28 in order to attach sample mounting chips such as are illustrated in FIG. 34 . FIG. 17 illustrates the graphic layout of sample chips 115 on the panel 28 . During installation, the flat panel 15 is inserted into the curved slots in the module and thereby is effectively turned into a curved panel, which is more suitable to a typical consumer's line of sight and results in improved, light distribution and space conservation.
[0061] FIGS. 18 thru 23 illustrate the recessed lighting fixture or “light box” 27 of FIG. 1 in more detail. The fixture 27 includes a number of pairs of fluorescent lamp fixtures 123 disposed within a housing 124 . Each lamp fixture 123 preferably includes a biaxial lamp unit, preferably a Philips PL-L55W, 55 watt, 5500 K, 92 CRI unit. A CRI of 90 or above is preferred. The housing 124 comprises a perforated horizontal mounting (ceiling) panel 121 , first and second rectangular vertical end members 125 , 126 and a rear edge member 127 . FIG. 19 illustrates a centered header attachment support 134 , and a rectangular reinforcement member 136 , which member 136 preferably extends the entire length of the light box 127 . The header support 134 and reinforcement member 136 serve to prevent sagging of the middle of the structure. The member 136 may, for example, be a metal tube or formed from a portion of a metal sheet used to fabricate panel 121 .
[0062] Each fixture of the pair of lighting fixtures 123 is mounted parallel to an adjacent fixture 123 and at a slight acute angle to the horizontal edge 130 of the mounting panel 121 . The acute angle may be for example eight (8) degrees. The light fixtures 123 are so arrayed as to create a uniform lighting effect on the concave display panels. As may be seen in FIG. 22 , the pairs of parallel light tubes of the fixtures 123 lie horizontally and provide a substantially linear line of light-radiating, surface.
[0063] FIG. 20 shows a detail of a lamp fixture 123 and its associated reflector 131 . A single side reflector 131 is positioned behind each lamp fixture 123 . The reflector 131 is especially designed with angled side sections 131 , 135 in order to appropriately direct the light. Angled section 133 may be ½″ in length and formed at an angle of 130 degrees with respect to horizontal portion 126 , which maybe 2.5 inches in width. Angled portion 135 may also be ½″ in length and formed at an angle of 160 degrees to angled portion 135 . The reflecting surface may be 95% reflective, 92% specular. The single side reflector 131 further directs light downwardly, preventing glare in the customer's eyes.
[0064] FIG. 23 illustrates a decorative front face plate 129 which closes the front of the fixture 27 and is seen by one viewing the display 11 . A diffuser grill 201 ( FIG. 1 ) is mounted at the bottom of the lamp fixture 27 and is further illustrated in FIGS. 23A and 23B . The diffuser may be a rectangular plastic grill (“egg crate” diffuser) comprising square openings each of which may be ½ inch on a side.
[0065] The lamp mounting arrangement shown in FIG. 18 positions a light producing lamp portion adjacent a “tombstone” lamp mounting receptacle. The light box 27 is relatively shallow in depth and the staggered arrangement of light fixtures 123 together with the diffuser 201 substantially eliminates dark spots and provides a uniform, customer-attracting and aesthetically pleasing light distribution.
[0066] FIGS. 24 and 25 illustrate an advantageous irrigation feature, which cooperates with sprinkler systems positioned above the display 11 to distribute the flow of fire retarding water throughout the unit and to goods, e.g., 202 ( FIG. 1 ), stored beneath the display 11 . As may be seen, the perforations, e.g., 122 , in the light fixture housing 121 cooperate with holes, e.g., 86 , 186 , in underlying module members to permit water flow down and throughout the display 11 and its modular components 17 , 19 , 21 , 23 , 25 . Holes 186 and 86 overlie matching holes, e.g., 57 in the cabinet 13 .
[0067] FIGS. 26 and 27 illustrate further details of the interactive video module 21 . The module 21 encloses a video display monitor 29 which has a display viewing screen 145 and user manipulated buttons 141 . The buttons 141 permit a user to step through a menu of audio/video displays describing, for example, various tasks required in applying and selecting stains, waterproofing, and other products.
[0068] FIG. 26 shows a cover plate 147 in a removed position, revealing a DVD/DVI player 143 . The DVD or DVI player 143 may be an adaptation of a commercially available unit providing a track selection feature cooperating with the buttons 141 . FIG. 27 further illustrates a display panel 151 partially inserted into the concave grooves 75 of the module 21 . The display panel 151 may carry, for example, four rows of wood chips, e.g., 152 , 151 selectively stained. Each of the chips 154 may comprise a different species of wood each stained with the same stain, thereby illustrating to the consumer the different effects which the underlying wood can have on the finished appearance of the stained wood.
[0069] FIGS. 28 thru 31 illustrate an apparatus and method for securing the modules 17 , 19 , 21 , 23 into the surrounding cabinet 13 . In particular, a flat horizontal panel 166 , preferably sheet metal, is provided with suitable parallel slots 163 and with a front molding piece 167 providing a vertically extending surface 170 for abutting respective noses 171 of the modules 17 , 19 , 21 , 23 , 25 . A stud 165 is positioned in each slot 163 and serves to position and guide the panel 166 . The panel 166 is slideable in and out between the shelf 56 and the base panels 47 , 71 , 92 , 73 , 105 of the respective modules 17 , 19 , 21 , 23 , 25 , guided by the studs 165 .
[0070] Considering FIGS. 29 and 30 , in the order to secure the modules 17 , 19 , 21 , 23 in place, the front molding piece 167 is pushed in towards the respective noses 171 of the modules 17 , 19 , 21 , 23 , 25 until the position shown in FIG. 30 is reached, at which point, screws or other devices are inserted through the holes 26 , 29 in the base of each of modules 17 , 25 , then through the sheet metal panel 166 , and finally into the shelf 56 , thereby securely fixing the molding piece 167 and hence the modules 17 , 19 , 21 , 23 , 25 in position. Other means of securing the modules in place can of course be used. In one alternate embodiment, for example, a piano hinge could be used to mount a suitable front molding piece 167 . It will also be noted further that the placement of the fastening devices through holes 26 , 29 in the respective brochure modules 17 , 25 renders them inconspicuous, for example, as compared to side insertion through panel 13 . FIG. 31 illustrates an alternate approach wherein a screw or other fastening device is inserted through a display panel, then through a module base and a sheet metal panel, and into the shelf 56 . The approach using holes 26 , 29 is preferred over this approach because it is less conspicuous.
[0071] FIGS. 32 through 37 illustrate a chip mounting mechanism 215 . As illustrated in FIG. 33 , the chip mounting mechanism includes a removable chip holder 217 , which mounts into a carrier 225 . Both the chip holder 217 and the carrier 225 may be fabricated, for example, of a suitable molded plastic.
[0072] The chip holder 217 includes a base portion 232 on which is formed first and second horizontal tabs 229 , 221 and an acutely angled tab 230 . The chip holder 217 further includes vertically depending edge portions 235 , 237 and respective lips 239 , 240 ( FIG. 35 ). Each lip 239 , 240 has a cammed surface 350 to facilitate installation as further described below.
[0073] As illustrated in FIG. 34 , the tabs 229 , 231 , 230 facilitate removable mounting of respective wood chips 219 , 221 , each of which has a groove 227 formed therein for slideably receiving the respective tabs 229 , 231 . The opposite ends of the respective chips 219 , 221 slide snuggly underneath the acutely angled tab 230 .
[0074] The carrier member 225 includes a flat rectangular bottom 253 and a generally rectangular rim 251 formed about the periphery of the bottom 253 . First and second slots 241 , 243 are formed in the carrier member 225 for receiving the respective tabs 239 , 240 ( FIG. 35 ) of the chip holder 217 . The vertically depending edge portions 235 , 237 of the chip holder 217 are sized such that they snuggly fit within the rectangular rim 251 of the carrier member 225 . On the underside of the bottom 253 of the carrier member 225 are formed respective expandable plugs 250 , which insert into respective adjacent mounting holes e.g., 261 , 263 formed in the display panel 28 .
[0075] FIGS. 35 through 37 illustrate the manner of insertion of the removable chip holder 217 into the carrier member 225 . As shown, the first lip 239 is engaged with the first slot 241 , and then the chip holder 217 is pressed downward such that the second lip 240 snaps into the slot 243 with the assistance of the cammed surface 350 , thereby snuggly joining the chip holder 217 and carrier member 225 together. Suitable wood chips, e.g., 229 may then be slideably inserted into the chip carrier 217 . Thereafter, the assembled unit may be mounted on the display panel 28 by inserting the prongs 250 through the respective mounting holes, e.g., 261 , resulting in the mounted position shown in FIG. 37 . The construction illustrated in FIGS. 32-37 permits sample chips to be removed by the retailer (but not the customer) for purposes of changing out or updating different chips, as desired.
[0076] Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other that as specifically described herein. | A plurality of separate display modules are interchangeably installed on a shelf of a cooperating cabinet structure and arranged to provide concavely curved display panels mounting selected arrangements of illuminated sample chips, an interactive video display, and brochure receptacles. The structure is provided with and integral sprinkler water distribution system and may include a two-part chip mounting mechanism which facilitates changing out of sample chips. | 0 |
This application is a continuation-in-part of U.S. patent application Ser. No. 08/164,892, filed Dec. 9, 1993, now U.S Pat. No. 5,490,768.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to multi-stage in-line pumps and, more particularly, to such pumps powered by integral canned electric motors.
2. Description of the Prior Art
Pumps are commonly used to move fluids through pipelines. One such application is the main seawater pump of a ship or other marine vessel. The main seawater pump provides cooling water flow to the secondary side of the steam turbine condenser system. The performance of the seawater pump and its reliability is vital to the safe and continuous operation of the vessel.
In modern warships, such as submarines, quiet operation is of the utmost importance. The main seawater pump is one of the most difficult pieces of machinery to silence. Noise emanating from the main seawater pump is coupled directly to the sea through the fluid that is being pumped. Because of that, isolation techniques are less effective and the pump must be intrinsically quiet.
Modern powerful propulsion plants require larger main seawater pumps which have increased noise potential. Speed of the impeller blade tips increases with both diameter and rotational speed. Broad band noise is estimated to increase as the sixth power of impeller blade tip speed. As the pump capacity and head increase, hydrodynamic loading of the impeller increases in order to keep size to a minimum. Greater increased hydrodynamic loading can result in greater susceptibility to cavitation which results in the pump operating more noisily.
In addition, because conventional main seawater pumps are typically driven by an external motor, the drive shaft connecting the motor and the impeller must penetrate the pipe wall. Mechanical seals at the interface are often highly complex and are the source of maintenance problems.
Efforts to silence conventional main seawater pumps have led to even further increases in size. One conventional design uses an involute casing in order to direct fluid flow for acoustical advantage. The resulting casing must be more than twice as large as an equivalent conventional casing.
Main seawater pumps typically become quieter when run at slower speeds. Adjustable speed pumps, which can be operated at different speeds depending on performance which is needed based on the operating conditions of the power plant, are desirable.
There is a need for a main seawater pump which can operate at lower speeds to reduce the noise generated by impeller cavitation while maintaining the desired level of performance. There also remains a need for a main seawater pump that can be operated at slower speeds to decrease the mechanical noise created by operation of the motor and pumps.
SUMMARY OF THE INVENTION
This invention provides an in-line, multi-stage pump utilizing canned electric motor technology. One application for such a pump is for main seawater pumps for marine vessels. Such pumps provide cooling water flow to the secondary side of steam turbine condensers. The pump includes at least two pump units connected in series in a flow path, such as an enclosed pipe line. Each pump unit includes a generally hollow housing secured into the flow path. The housing includes an inlet end and an outlet end. An annular stator is mounted inside the housing. Electrical power is supplied to the stator from an external power source such as a generator. An impeller assembly is rotatably mounted in the hollow portion of the housing. The impeller assembly includes a tubular suction shroud extending through and rotatable relative to the annular stator. An impeller is secured to the tubular suction shroud. An annular rotor is mounted around the suction shroud and positioned inside the annular stator to form an electric motor. When the stator is energized, the rotor rotates, thereby rotating the tubular suction shroud and impeller to create a pressurized flow of water through the housing from the inlet end to the outlet end.
The tubular suction shroud preferably has a forward end and an aft end. The forward end is positioned to form a forward gap relative to the housing and the aft end is positioned to form an aft gap relative to the housing. The forward gap and the aft gap are in communication with one another forming a water circulation channel between the rotor and the housing. The forward gap is preferably on the inlet side of the impeller and the aft gap is preferably on the outlet side of the impeller. When the impeller is rotating, water pressure will be higher at the outlet end than at the inlet end of the housing. Water will flow from the higher pressure area at the aft gap to the lower pressure area at the forward gap to cool the motor.
At least one water cooled, hard surface bearing is preferably mounted on the housing and the impeller assembly and is positioned in the water circulation channel to rotatably support the impeller assembly.
In another embodiment of this invention, each pump unit is provided with some hubs centrally mounted inside of and secured to the housing. The hub is positioned either upstream or downstream from the impeller, relative to the direction of water flow, such that water passing from the inlet end to the outlet end of the housing must pass by the hub. The hub may rotatably support a portion of the impeller assembly. The hub may be secured to the housing by one or more flow straightening vanes, pre-swirl vanes or struts.
The impeller assembly preferably includes a generally hollow shaft rotatably mounted in the hub. The shaft has an opening into the hollow portion on the intake side of the impeller. A second aft end of the suction shroud forms a hub gap relative to the hub and on the outlet side of the impeller. The hub gap and the opening in the shaft are preferably in communication with one another to form a second water circulation channel between the hub and the tubular suction shroud. Water cooled, hard surface radial bearings are mounted on the hub and tubular suction shroud and positioned in the second water circulation channel. The bearings rotatably support the tubular suction shroud. Hard surface, water cooled thrust bearings may be mounted on the impeller assembly and one of the hub or the housing. A separate water circulation pump may be provided to supply cooling and lubricating water to the bearings.
The housing of each pump unit of this invention may also include a water cooling jacket around the stator. The water jacket is preferably in communication with the water flowing through the housing such that water will flow through the cooling jacket to cool the stator during operation. Alternatively, a separate source of clean cooling water may be provided for circulation through the cooling jacket.
The multi-stage, in-line configuration permits lower impeller vane tip speed than may be obtained in conventional pumps operating at the same pressure and flow rate. Lower vane tip speed greatly reduces cavitation and the associated noise. The configuration also provides redundancy and an expanded range of operating modes. It also reduces weight and size associated with conventional pump casings and eliminates the need for shaft seals where the impeller drive shaft enters the pipe line.
This invention will be more fully understood from the following detailed description of preferred embodiments on reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view of one embodiment of the pump of this invention.
FIG. 2 is a longitudinal sectional view of the housing and hub of one pump unit of the pump of FIG. 1.
FIG. 3 is a longitudinal sectional view of the impeller assembly of one pump unit of the pump of FIG. 1.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIGS. 1 through 3, there is shown a preferred embodiment of the pump 2 of this invention. Pump 2 includes two generally identical pump units 3, 3' connected in series in a pipeline 5. For simplicity of description, reference will be made to only one of the pump units 3 in describing the components of the pump unit. The other pump unit 3' is identical to pump unit 3. Each pump unit 3 includes a generally hollow housing 4 secured in the pipeline. Housing 4 has an inlet end 10 and an outlet end 12. An annular stator 14 is mounted inside housing 4. As may best be seen in FIG. 2, amnular stator 14 is hermetically sealed inside housing 4 by stator can 16. Energizing means 18 provide electrical power to stator 16 (FIG. 1). Energizing means 18 preferably include a generator, or other source of electrical power, electrically connected to stator 14. The generator may be positioned in a location in the vessel that is remote from pump 2 since only electrical connections to the pump units, rather than mechanical connections, are required.
Each pump unit of pump 2 further comprises an impeller assembly 20. Impeller assembly 20 includes a tubular suction shroud 22 extending through and rotatable relative to annular stator 14. An impeller 24 is secured to suction shroud 22. The vanes of impeller 24 may be secured to suction shroud 22 by welding or any other suitable manner known to those skilled in the art. The number of blades on impeller 24 and the blade configuration will depend on the desired performance of the pump and may be determined in a manner known to those skilled in the art. In a preferred embodiment, impeller 24 is a single stage, mixed flow type impeller. It will be apparent, however, that an impeller having one or more centrifugal, axial or mixed flow type stages may be utilized. A rotor 26 is mounted around tubular suction shroud 22 and inside stator 14. Rotor 26 and stator 14 preferably cooperate to form an induction motor. Rotor 26 is preferably a squirrel cage rotor so that no electrical connections to the rotor are required. It will be appreciated, however, that the motor could be a synchronous motor. Rotor 26 is preferably shrink fitted onto suction shroud 22. Rotor 26 is preferably hermetically sealed by rotor can 28. Energizing stator 14 causes rotor 26 to rotate, thereby rotating suction shroud 22 and impeller 24 to create a pressurized flow of water through the housing 4 from inlet end 10 to outlet end 12. The pumping action of the rotation of impeller 24 adds head and velocity to the water, which causes the water pressure to be higher on the outlet side of the impeller than on the inlet side thereof.
In a preferred embodiment, hub 30 is centrally positioned and secured to housing 24 adjacent to outlet end 12. Hub 30 is preferably secured to housing 4 by seven flow straightening vanes 32. However, it will be appreciated that any suitable number of straightening vanes 32 may be used. The desired number of straightening vanes provided may be determined in a manner known to those skilled in the art. Alternatively, hub 30 may be secured to housing 4 by a plurality of struts which have little affect on the water flow. A combination of struts and vanes may also be used. Water flows around hub 30 from inlet end 10 to outlet end 12. The straightening vanes 32 reduce the magnitude of the circular component of motion of the flowing water which is produced by the action of rotating impeller 24.
Impeller assembly 20 preferably includes a generally hollow shaft 34. Shaft 34 has an opening 36 into the central hollow portion thereof. Opening 36 is on the inlet side of impeller 24. Shaft 34 is received into hub 30, thereby rotatably supporting impeller assembly 20.
Tubular suction shroud 22 has a forward end 38 that forms a forward gap 40 relative to housing 4 on the inlet side of impeller 24. Forward gap 40 is adjacent to the inlet end 10 of housing 4 on the inlet side of impeller 24. Tubular suction shroud 22 also has a first aft end 42 forming an aft gap 44 relative to housing 4. Aft gap 44 is on the outlet side of impeller 24. Forward gap 40 and aft gap 44 are preferably in communication with one another, thereby forming a first water circulation channel 46 between rotor 26 and housing 4. During operation, water flowing through housing 4 enters aft gap 44, where the pressure is higher, flows through first water circulation channel 46 and exits through forward gap 40 into the water flowing through housing 4. The water flowing through first water circulation channel 40 cools stator 14 and rotor 26.
Tubular suction shroud 22 preferably also has a second aft end 48 forming a hub gap 50 relative to hub 30 and on the outlet side of impeller 24. Hub gap 50 and opening 36 in shaft 34 are in communication with one another thereby forming a second water circulation channel 52 between hub 30 and tubular suction shroud 22. Water enters hub gap 50, flows through second water circulation channel 52 and exits through opening 36 in shaft 34.
First radial bearings 54 are mounted between housing 4 and suction shroud 22 to rotatably support one end of suction shroud 22. First bearings 54 are preferably one or more hard surface, water cooled pivoted pad or plain journal bearings mounted around the circumference of housing 4 and tubular suction shroud 22. Bearings 54 are preferably in communication with first water circulation channel 46. Water flowing in first water circulation channel 46 also cools and lubricates the bearings. The pads of the bearings of first radial bearings 54 are preferably made of a hard alloy material, such as tungsten carbide, or other suitable material that will not be damaged by sand and other material that may be present in the flowing water.
Second radial bearings 56 are mounted between impeller assembly 20 and hub 30 to rotatably support another end of suction shroud 22. Second radial bearings 56 preferably include one or more hard surface, water-cooled, pivoted pad or plain journal bearings mounted around the circumference of shaft 34 in second water circulation channel 52. Water flowing in second water circulation channel 52 flows over the bearings to cool and lubricate them. The pads of second radial bearings 56 are preferably made of a hard alloy material, such as tungsten carbide, or other suitable material, to minimize the likelihood of damage resulting from sand or other contaminants in the flowing water.
Thrust bearings 58 are preferably mounted between impeller assembly 20 and hub 30. Thrust bearings 58 preferably consist of double acting, water-cooled, self-leveling Kingsbury-type bearings. Thrust bearings 58 are mounted in second water circulation channel 52. Water flowing in second water circulation channel 52 cools and lubricates thrust bearings 58. The pads and thrust runner surfaces of thrust bearings 58 are preferably made of the same materials as the pads of the radial bearings to minimize damage from contaminants in the water flow.
Housing 4 may be provided with a cooling jacket around annular stator 14. Cooling jacket 57 includes water inlet means 59 in communication with the water flowing through housing 4 and located adjacent to outlet end 12. Cooling jacket 57 also includes water outlet means 61 in communication with the water flowing through housing 4 and adjacent to inlet end 10. Water enters the cooling jacket through water inlet means 59, circulates through water cooling jacket 57 and is discharged back into the flow of water in housing 4 through water outlet means 61. The water flowing in cooling jacket 57 provides additional cooling for stator 14 if necessary.
In operation, energization of stator 14 causes rotor 26 to rotate. Rotation of rotor 26 also rotates impeller assembly 20, which creates a pumping action. Water, sea water or fresh water, is pumped from the water in which the vessel is floating through inlet conduit 60. The rotating impeller 24 imparts velocity to the water and adds head to the water flow, thereby pressurizing the water. The higher pressure water is discharged out outlet end 12 to flow through the pipeline 5 and into the next pump unit 3'. Pump units 3, 3' may be positioned within pipeline 5 in virtually any desired configuration. The pump units may be positioned immediately adjacent to one another so that discharge from pump unit 3 initially flows into the inlet end 10 of pump unit 3'.
Alternatively, the pump units may be spaced from one another. In addition, the pump units may be positioned in a horizontal section of pipeline, in a vertical section of pipeline, in portions of the pipeline offset by an elbow, or in any desired location in the pipeline.
In a preferred embodiment, two pump units are provided. However, it will be appreciated that any desired number of pump units may be provided to achieve the desired performance.
The use of two pump units permits the pump units to operate at lower rpm, and, thus, lower impeller blade tip speeds thereby reducing cavitation noise. The lower rpm also produce less acoustical mechanical noise and requires less power to operate. The pump units may be operated independently, at the same or different speeds to produce the desired performance. In addition, the multi-stage configuration provides redundancy for continued operation of the system in the event of a failure of one pump unit.
It will be appreciated that this invention provides a multi-stage in-line pump which is quieter and more flexible than conventional installations and which also eliminates the need for a drive shaft to be mechanically connected to the impeller and mounted in the pipeline. In one application of the invention, the pump 2 such as formed by the pumps 3 and 3', draw water through the secondary side 63 of a steam turbine condenser system (STSC) 65 of a marine vessel through the pipe 5, as indicated in FIG. 1.
Whereas particular embodiments of this invention have been described for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details may be made without departing from the invention as described in the appended claims. | An in-line, multi-stage pump powered by integral canned electric motors. At least two pump units are connected in series in a pipeline. Each of said pump units includes a hollow housing having a hermetically sealed stator mounted therein. The stator is electrically connected to a source of electrical energy. An impeller assembly that includes a tubular suction shroud and impeller is rotatably mounted inside the housing. The impeller assembly includes a hermetically sealed rotor which is mounted around the suction shroud and positioned inside the stator in operative association therewith. Energizing the stator rotates the rotor, which in turn rotates the impeller to pump fluid from the intake end of the housing to the outlet end of the housing. The subsequent pump units add pressure and/or maintains the pressure of the pumped fluid. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates broadly to ophthalmic implants. More particularly, this invention relates to intraocular lenses which are focusable and allow for accommodation for near vision.
[0003] 2. State of the Art
[0004] Referring to FIG. 1 , the human eye 10 generally comprises a cornea 12 , an iris 14 , a ciliary body (muscle) 16 , a capsular bag 18 having an anterior wall 20 and a posterior wall 22 , and a natural crystalline lens 24 contained with the walls of the capsular bag. The capsular bag 18 is connected to the ciliary body 16 by means of a plurality of zonules 26 which are strands or fibers. The ciliary body 16 surrounds the capsular bag 18 and lens 24 , defining an open space, the diameter of which depends upon the state (relaxed or contracted) of the ciliary body 16 .
[0005] When the ciliary body 16 relaxes, the diameter of the opening increases, and the zonules 26 are pulled taut and exert a tensile force on the anterior and posterior walls 20 , 22 of the capsular bag 18 , tending to flatten it. As a consequence, the lens 24 is also flattened, thereby undergoing a decrease in focusing power. This is the condition for normal distance viewing. Thus, the emmetropic human eye is naturally focused on distant objects.
[0006] Through a process termed accommodation, the human eye can increase its focusing power and bring into focus objects at near. Accommodation is enabled by a change in shape of the lens 24 . More particularly, when the ciliary body 16 contracts, the diameter of the opening is decreased thereby causing a compensatory relaxation of the zonules 26 . This in turn removes or decreases the tension on the capsular bag 18 , and allows the lens 24 to assume a more rounded or spherical shape. This rounded shape increases the focal power of the lens such that the lens focuses on objects at near.
[0007] As such, the process of accommodation is made more efficient by the interplay between stresses in the ciliary body and the lens. When the ciliary body relaxes and reduces its internal stress, there is a compensatory transfer of this stress into the body of the lens, which is then stretched away from its globular relaxed state into a more stressed elongated conformation for distance viewing. The opposite happens as accommodation occurs for near vision, where the stress is transferred from the elongated lens into the contracted ciliary body.
[0008] In this sense, referring to FIG. 2 , there is conservation of potential energy (as measured by the stress or level of excitation) between the ciliary body and the crystalline lens from the point of complete ciliary body relaxation for distance vision through a continuum of states leading to full accommodation of the lens.
[0009] As humans age, there is a general loss of ability to accommodate, termed “presbyopia”, which eventually leaves the eye unable to focus on near objects. In addition, when cataract surgery is performed and the natural crystalline lens is replaced by an artificial intraocular lens, there is generally a complete loss of the ability to accommodate. This occurs because the active muscular process of accommodation involving the ciliary body is not translated into a change in focusing power of the implanted artificial intraocular lens.
[0010] There have been numerous attempts to achieve at least some useful degree of accommodation with an implanted intraocular lens which, for various reasons, fall short of being satisfactory. In U.S. Pat. No. 4,666,446 to Koziol et al., there is shown an intraocular lens having a complex shape for achieving a bi-focal result. The lens is held in place within the eye by haptics which are attached to the ciliary body. However, the implant requires the patient to wear spectacles for proper functioning. Another device shown in U.S. Pat. No. 4,994,082 to Richards et al., also utilizes a lens having regions of different focus, or a pair of compound lenses, which are held in place by haptics attached to the ciliary body. In this arrangement, contraction and relaxation of the ciliary muscle causes the haptics to move the lens or lenses, thereby altering the effective focal length. There are numerous other patented arrangements which utilize haptics connected to the ciliary body, or are otherwise coupled thereto, such as are shown in U.S. Pat. No. 4,932,966 to Christie et al., U.S. Pat. No. 4,888,012 to Horne et al. and U.S. Pat. No. 4,892,543 to Turley, and rely upon the ciliary muscle to achieve the desired alteration in lens focus.
[0011] In any arrangement that is connected to the ciliary body, by haptic connection or otherwise, extensive erosion, scarring, and distortion of the ciliary body usually results. Such scarring and distortion leads to a disruption of the local architecture of the ciliary body and thus causes failure of the small forces to be transmitted to the intraocular lens. Thus, for a successful long-term implant, connection and fixation to the ciliary body is to be avoided if at all possible.
[0012] In U.S. Pat. No. 4,842,601 to Smith, there is shown an accommodating intraocular lens that is implanted into and floats within the capsular bag. The lens comprises front and rear flexible walls joined at their edges, which bear against the anterior and posterior inner surfaces of the capsular bag. Thus, when the zonules exert a tensional pull on the circumference of the capsular bag, the bag, and hence the intraocular lens, is flattened, thereby changing the effective power of refraction of the lens. The implantation procedure requires that the capsular bag be intact and undamaged and that the lens itself be dimensioned to remain in place within the bag without attachment thereto. Additionally, the lens must be assembled within the capsular bag and biasing means for imparting an initial shape to the lens must be activated within the capsular bag. Such an implantation is technically quite difficult and risks damaging the capsular bag, inasmuch as most of the operations involved take place with tools which invade the bag. In addition, the Smith arrangement relies upon pressure from the anterior and posterior walls of the capsular bag to deform the lens, which requires that the lens be extremely resilient and deformable. However, the more resilient and soft the lens elements, the more difficult assembly within the capsular bag becomes. Furthermore, fibrosis and stiffening of the capsular remnants following cataract surgery may make this approach problematic.
[0013] U.S. Pat. No. 6,197,059 to Cumming and U.S. Pat. No. 6,231,603 to Lang each disclose an intraocular lens design where the configuration of a hinged lens support ostensibly allows the intraocular lens to change axial position in response to accommodation and thus change effective optical power. U.S. Pat. No. 6,299,641 to Woods describes another intraocular lens that also increases effective focusing power as a result of a change in axial position during accommodation. In each of these intraocular lenses, a shift in axial position and an increase in distance from the retina results in a relative increase in focusing power. All lenses that depend upon a shift in the axial position of the lens to achieve some degree of accommodation are limited by the amount of excursion possible during accommodation.
[0014] U.S. Pat. No. 5,607,472 to Thompson describes a dual-lens design. Prior to implantation, the lens is stressed into a non-accommodative state with a gel forced into a circumferential expansion channel about the lens. At implantation, the surgeon must create a substantially perfectly round capsullorrhexis, and insert the lens therethrough. A ledge adjacent to the anterior flexible lens is then bonded 360° around (at the opening of the capsulorrhexis) by the surgeon to the anterior capsule to secure the lens in place. This approach has numerous drawbacks, a few of which follow. First, several aspects of the procedure are substantially difficult and not within the technical skill level of many eye surgeons. For example, creation of the desired round capsullorrhexis within the stated tolerance required is particularly difficult. Second, the bonding “ledge” may disrupt the optical image produced by the adjacent optic. Third, intraocular bonding requires a high degree of skill, and may fail if the capsullorrhexis is not 360° round. Fourth, the proposed method invites cautionary speculation as to the result should the glue fail to hold the lens in position in entirety or over a sectional region. Fifth, it is well known that after lens implantation surgery the capsular bag, upon healing, shrinks. Such shrinking can distort a lens glued to the bag in a pre-shrunk state, especially since the lens is permanently affixed to a structure which is not yet in equilibrium. Sixth, Thompson fails to provide a teaching as to how or when to release the gel from the expansion channel; i.e., remove the stress from the lens. If the gel is not removed, the lens will not accommodate. If the gel is removed during the procedure, the lens is only in a rounded non-stressed shape during adhesion to the capsule, and it is believed that the lens will fail to interact with the ciliary body as required to provide the desired accommodation as the capsular bag may change shape in the post-operative period. If the gel is removed after the procedure, it is ostensibly via an additional invasive surgical procedure. In view of these problems, it is doubtful that the lens system disclosed by Thompson can be successfully employed.
[0015] Co-owned U.S. Pat. No. 7,601,169 to Phillips describes an intraocular lens for placement within the capsular bag. The lens includes an optic portion and a surrounding peripheral portion. A bias element is provided to anteriorly vault the optic portion relative to the peripheral portion. A restraint is provided to counter the bias element, and constrain the lens in stressed relatively planar configuration during surgical implantation and a healing period during which the eye is maintained under cycloplegia and the peripheral portion and capsular bag are permitted to naturally fuse together. Then, post-healing, the restraint is removed permitting the bias element to vault the optic portion anteriorly into a non-stressed state such that the optic portion is at an increased distance from the retina relative to the stressed state and has a resulting increased optical power, and wherein the optical power of the lens is adjustable in response to stresses induced by the eye. While significant advantage is provided by the system, limitations in optical power remain from the system.
[0016] U.S. Pat. No. 8,034,106 to Mentak describes an intraocular lens retained outside the lens capsule in the posterior chamber. The lens has haptics coupled to the ciliary body. The optic of the lens includes an encapsulation of two immiscible liquids in contact with other and defining a meniscus at their interface. Alternatively, two miscible liquids are encapsulated and separated by an optically transparent film at their meniscus. Forces from the ciliary body are transmitted through the haptics to the interface of the liquids to alter the curvature of the meniscus, and thus alter the accommodating power of the lens. While Mentak considers it an advantage, it may also be considered a drawback that the Mentak lens uses two liquids within the optic of the lens. Should the lens leak such liquid, there is serious concern with respect to the impairment and damage that may be result. In addition, it is possible that over time the liquids may migrate out of the lens, causing ocular damage or changing the optical power, or the liquids may crystallize also leading to vision impairment.
[0017] Thus, the prior art discloses numerous concepts for accommodating intraocular lenses. However, none are capable of providing an accommodating implant which does not, in one way or another, present technical barriers or potential serious consequences upon failure of the device or provide an system to which their may be improvement.
SUMMARY OF THE INVENTION
[0018] An intraocular lens (IOL) according to the invention permits accommodation through two different mechanisms. The IOL includes an optic and haptic levers. The optic has an anterior surface and a posterior surface and is defined by a first polymeric optic layer and a second optic polymeric layer positioned on the first optic layer. The first polymeric optic layer has a first durometer, an anterior surface, and a posterior surface that defines the posterior surface of the optic. The posterior surface of the first layer has a generally spherical curvature, and the anterior surface of the first layer has an outer portion with a first spherical curvature, and a smaller diametered central portion with a steeper shape, preferably of a second spherical curvature of a lesser radius of curvature than the first spherical curvature. The second polymeric optic layer is relatively softer, with a second durometer lower than the first durometer, an anterior surface with a generally spherical curvature, and a posterior surface that is provided flush against anterior surface of the first layer.
[0019] The haptic levers can alter the axial position of the optic within the posterior chamber and deform the second optic layer, each operating to change the optical power of the lens. The haptic levers include a fulcrum attached at the periphery of the first optic layer, a resistance arm coupled to the anterior surface of the second optic layer, and a force arm haptic which engages within the capsular bag. When a force is applied to the haptic levers to cause relatively posterior bending or rotation of the haptic levers relative to the optic, the haptic levers are bent or rotated relative to the first layer, and the following two mechanism are effected to increase the optical power of the IOL. First, as the levers rotate about the fulcrums, the resistance arms stretch at least the anterior surface of the second optic layer. This results in deformation of the second optic layer as the second optic layer bends about the smaller diameter central portion on the anterior surface of the first optic layer to thereby decrease its radius of curvature (steepen the curvature) and consequently increase the central optical power of the lens. Second, with the force arms fixed in the edges of the capsular bag, as the levers bend or rotate about the fulcrums, the entire optic is axially displaced anteriorly to increase the optical power of the lens. This state of increased power permits accommodation.
[0020] For the lens to function optimally in accommodation, the haptic levers are subject to a pre-bias such that the levers are naturally biased or otherwise urged to rotate or bend about the fulcrums to stretch at least the anterior surface of the second optic layer and to anteriorly displace the optic relative to the free ends of the force arms. Such pre-bias is preferably applied by integration of a bias element at the haptic-optic junction. Such bias element may comprise a resilient polymer hinge and may be integrated as a periphery of the first optic layer.
[0021] When the IOL is held by the optical system or otherwise with the haptic levers and optic of the IOL in a more planar configuration, the force of the bias element must be overcome. The lens is therefore in a stressed state, but the anterior curvature of the lens is flatter and of a lower power suitable for non-accommodative vision.
[0022] A restraining element is preferably provided to the IOL for temporarily retaining the IOL in a stressed, planar, non-accommodating configuration during implantation and a post-operative period. The retraining element may comprise a dissolvable bioabsorbable material such that the element automatically releases the optic after a post-operative period, or may be released under the control of an eye surgeon, preferably via a non-surgically invasive means such as via a laser or a chemical agent added to the eye.
[0023] Generally, the method for implanting the intraocular lens includes (a) inducing cycloplegia; (b) providing the intraocular lens having an optic portion and haptic levers and having an as manufactured inherent bias induced between the optic portion and haptic levers, the intraocular lens being held in a stressed, planar, non-accommodating state by a restraining means such that the intraocular lens has a lower optical power relative to an accommodating non-stressed state of the lens; (c) inserting the stressed state intraocular lens into a capsular bag of the eye; (d) maintaining cycloplegia until the capsular bag physiologically affixes to the intraocular lens; and (e) releasing the restraining means to permit the intraocular lens to move from the stressed state into the non-stressed state in which the intraocular lens has an increased optical power, and wherein the optical power of the intraocular lens is reversibly adjustable in response to stresses induced by the eye such that the lens can accommodate.
[0024] More particularly, according to a preferred method of implantation, the ciliary body muscle is pharmacologically induced into a relaxed stated (cycloplegia), a capsulorrhexis is performed on the lens capsule, and the natural lens is removed from the capsule. The prosthetic lens is then placed within the lens capsule. According to a preferred aspect of the invention, the ciliary body is maintained in the relaxed state for the duration of the time required for the capsule to naturally heal and shrink about the lens; i.e., possibly for several weeks. After healing has occurred, the restraining element automatically or under surgeon control releases the lens from the stressed state. The ciliary body and lens may then interact in a manner substantially similar to the physiological interaction between the ciliary body and a healthy natural crystalline lens.
[0025] Alternatively, a fully relaxed lens (i.e., without restraining element) can be coupled to a fully stressed and contracted ciliary body.
[0026] The intraocular lens of the invention is compatible with modern cataract surgery techniques and allows for large increases in optical power of the implanted lens. Unlike other proposed accommodating intraocular lens systems, the lens utilizes a change in shape in addition to axial displacement of the lens. In addition, given the fully polymerized materials of the lens, it is safe to use, eliminating various factors from the prior art that can lead to tissue irritation and damage and vision impairment.
[0027] Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Prior Art FIG. 1 is a diagrammatic view of a cross-section of a normal eye.
[0029] Prior Art FIG. 2 is a graph of the stresses on the ciliary body-crystalline lens system of the eye in a continuum of states between distance vision and full accommodation.
[0030] FIG. 3 is a schematic view of an intraocular lens according to the invention in a non-stressed, accommodating configuration.
[0031] FIGS. 4-6 illustrate manufacture of the intraocular lens of FIG. 3 into a restrained, stressed configuration suitable for implantation.
[0032] FIG. 7 shows the intraocular lens implanted in a lens capsule of an eye in a stressed, non-accommodative state.
[0033] FIG. 8 shows the intraocular lens implanted in a lens capsule of an eye in a non-stressed, accommodative state.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] Turning now to FIG. 3 , an intraocular lens (IOL) 100 according to the invention is shown. The IOL 100 includes an optic 102 for focusing light and one or more haptic levers 104 . The optic 102 has an overall diameter preferably approximately 4±2 mm, and most preferably 4.75 mm. The optic 102 is defined by a posterior first polymeric optic layer 106 and an anterior second optic polymeric layer 108 positioned on the first optic layer. The posterior first optic layer 106 defines a posterior surface of the optic, and the anterior second optic layer 108 defines an anterior surface of the optic. The first polymeric optic layer 106 is manufactured from a fully-polymerized optically transparent material, preferably a silicone, and has a first durometer preferably in the range of 30 to 60 Shore D. The first optic layer has a posterior surface 110 and an anterior surface 112 . The posterior surface 110 of the first optic layer has a generally spherical curvature, and the anterior surface 112 of the first optic layer has a peripheral portion 114 approximating the overall optic diameter and having a first spherical curvature, and a smaller diameter steeper central portion 116 , approximately 3±1 mm, preferably having a second spherical curvature of lesser radius of curvature than the first spherical curvature. Alternatively, the steeper central portion may be defined by a cone or a conical or frustoconical section. As yet another alternative, the steeper central portion may be defined by another shape, including an aspherical curve, a square edge, or a catenary. The second optic layer 108 has a posterior surface 120 that is bonded flush against the anterior surface 112 of the first optic layer 106 and an anterior surface 122 with a generally spherical curvature. The second optic layer 108 is made from a fully-polymerized optically transparent material, preferably a silicone, with a second durometer lower than the first durometer and preferably not exceeding 20 Shore D. The second optic layer preferably has a maximum thickness of 80-750 μ.
[0035] As discussed in more detail below, when the lens 100 is implanted in the capsular bag, forces from the ciliary body of the eye act through the capsular bag and on the one or more haptic levers 104 to (1) alter the axial position of the optic 102 within the posterior chamber of the eye and (2) alter the shape of the second optic layer 108 , each of which operates to change the optical power of the lens 100 . The haptic levers 104 are stated to be ‘one or more’ as such may comprise a single ring-shaped lever completely or substantially encircling the periphery of the optic 100 , or may comprise a plurality of haptic levers in a preferably evenly radially spaced apart distribution about the periphery of the optic. In the illustrated embodiment, two haptic levers 104 are shown in diametric opposition. However, where a plurality of haptic levers are provided, it is appreciated that two, three, four or more haptic levers can be preferably evenly displaced about the periphery of the optic.
[0036] The haptic levers 104 include a fulcrum 130 attached at a peripheral portion 128 (either at one or both of the anterior or posterior surfaces thereof or at the junction of the anterior and posterior surfaces) of the first optic layer 106 , a resistance arm 132 coupled to the periphery of the anterior surface 122 of the second optic layer 108 , and a force arm 134 having a free 136 end which is adapted to engage the capsular bag near the ciliary body. The haptic levers 104 are also made from a polymer, and more preferably from the same polymer with same hardness/softness as the first optic layer 106 . The resistance arms 132 are preferably 200-500 μ in length, and the force arms 134 are preferably 2.75 mm in length.
[0037] When a force is applied to the haptic levers 104 to cause relatively posterior rotation of the haptic levers relative to the optic 102 (in the direction of arrows 138 ), the haptic levers 104 are rotated relative to the first optic layer 106 , and the following two mechanism are effected to increase the optical power of the lens. First, as the haptic levers 104 rotate on the fulcrums 130 , the resistance arms 132 stretch at least the anterior surface 122 of the second optic layer 108 . This results in deformation of the second optic layer 108 as the second optic layer bends about the smaller diameter central portion 116 on the anterior surface of the first optic layer 106 to thereby decrease its radius of curvature and consequently increase the optical power of the lens 100 . Second, with the force arms 134 fixed in the edges of the capsular bag, as the levers 104 rotate about their respective fulcrums 130 , the entire optic 102 is axially displaced anteriorly (in the direction of arrow 140 ) within the posterior chamber to increase the optical power of the lens. This state of increased power permits accommodation.
[0038] For the lens to function optimally in accommodation, the haptic levers are preferably subject to a pre-bias such that the levers are naturally urged to rotate or bend about the fulcrum into an approximately 40°±10° angular bend relative to the diameter of the optic to thereby stretch at least the anterior surface of the second optic layer and to anteriorly displace the optic relative to the free ends of the force arms. Such pre-bias is preferably applied by a bias structure 142 at the haptic-optic junction, and may comprise a resilient polymer hinge 142 a integrated at the periphery of the first optic layer 106 or may include a separate bias element 142 b acting between the posterior first optic layer 106 and the haptic levers 104 .
[0039] Referring to FIGS. 4 through 6 , construction of the optic is preferably as follows. Referring initially to FIG. 4 , the posterior first optic layer 106 is molded, preferably with the haptic levers 104 integrated via the molding process. In the first step of the molding process, the fulcrums 130 of the haptic levers 104 are molded into the first optic layer 106 at the periphery 114 of the first optic layer, and the haptic levers 104 are oriented angled posteriorly to the first optic layer to cause the first optic layer 106 to be in a ‘vaulted’ configuration relative to the force arms 134 of the haptic levers. In an alternative manufacture, the first optic layer 106 and the haptic levers 130 may be integrated at a lesser angle or even in a relatively flat configuration, and a separate bias element 142 b is thereafter provided at the haptic-optic junction to bias the construct into the ‘vaulted’ configuration. Turning now to FIG. 5 , once the first optic layer 106 is integrated with the haptic levers 130 , the first optic layer 106 and haptic levers 130 are held in a substantially planarized configuration; i.e., with the force arms 134 extending substantially parallel (preferably within ±5°) with the diameter D of the first optic layer 106 , and the second optic layer is molded onto the anterior surface of the first optic layer and with the periphery of the second optic layer 108 coupling to the resistance arms 132 of the haptic levers 130 .
[0040] Referring now to FIG. 6 , once the second optic layer 108 has at least substantially cured on the first optic layer 106 , a temporary restraint is provided to the optic to maintain the planarized non-accommodative configuration for purposes of implantation and a for a period of post-implantation. Several types of temporary restraints may be used. In one example, the temporary restraint is a suture 146 extending from a first haptic lever 130 across the anterior surface of the second optic layer 108 to a second haptic lever 130 . The suture may extend through and be secured at a small hole 148 in the respective haptic levers. The suture is sufficiently taught to maintain the planarized configuration. Alternative restraints includes rigid struts attached to the hatpic levers and extending across the front or back of the optic to maintain the planarized configuration. Yet other alternative restraints include hinge stops at the optic-haptic junction that maintain the planarized configuration by preventing rotation of the haptic levers relative to the optic. Each of the restraints may be made of a dissolvable bioabsorbable material such that the restraint automatically releases the lens from the planarized configuration after a determined post-operative period, or may be released under the control of a eye surgeon, preferably via a non-surgically invasive means such as via a laser or a chemical agent added to the eye.
[0041] The lens is implanted in the eye as follows. The patient is prepared for cataract surgery in the usual way, including full cycloplegia (paralysis of the ciliary body). Cycloplegia is preferably pharmacologically induced, e.g., through the use of short-acting anticholinergics such as tropicamide or longer-lasting anticholinergics such as atropine. An anterior capsullorrhexis is then performed and the lens material removed. A stressed planarized lens according is selected that has an optic portion that in a stressed-state has a lens power that will leave the patient approximately emmetropic after surgery. The lens is inserted into the empty capsular bag. Cycloplegia is maintained for several weeks (preferably two to four weeks) or long enough to allow the capsular bag to heal and “shrink-wrap” around the stressed lens. This can be accomplished post-operatively through the use of one percent atropine drops twice daily. As the capsular bag shrinks, the anterior and posterior capsular bag walls join to the lens. If the lens includes a restraining element having a dissolvable component, eventually the dissolvable material is lost from the lens, and the lens is unrestrained. If the lens includes a restraining element having a laser-removable component, a surgeon may at a desired time remove the component to place the lens in a unrestrained configuration. If the lens includes a retraining element which must be otherwise removed from the patient, either via a non-surgically invasive procedure or a surgically invasive procedure, the surgeon may at a desired time perform a second eye procedure to remove the component and place the lens in an unrestrained configuration. Regardless of the method used, when the lens is unrestrained (i.e., released from the stressed state) as shown in FIG. 7 , and the post-operative cycloplegic medicines are stopped, the lens 100 is initially still maintained in a stressed state due to the inherent stress of the zonules in the non-accommodating eye. When the patient begins accommodating, the zonular stress is reduced and the implanted lens is permitted to reach a more relaxed configuration, as shown in FIG. 8 . With release of the zonular stress, the haptics levers 130 reconfigure the lens in accord with the inherent bias of the lens; i.e., to rotate approximately 40°±10° relative to the diameter D of the posterior optic layer 106 causing (1) deformation of the anterior optic layer 108 about the central portion 116 of the posterior optic layer 106 to a cause the anterior optic layer to assume a steeper curvature of greater optical power at the center thereof and (2) anterior axial displacement of the optic 102 relative to the free ends 136 of the haptic levers 130 . Theses changes in shape provide the lens with greater dioptic power in the central portion of the optic 102 , and thus accommodation for the patient is enabled. As with the natural crystalline lens, the relaxation of the implanted lens, i.e., its permitted movement in accord with its inherent bias, is coupled with a development of strain or stress in the ciliary body during accommodation. Further, when the patient relaxes accommodation, the stress in the ciliary body is reduced, and there is a compensatory gain in stress as the lens is stretched into its planar, non-accommodative shape shown in FIG. 7 .
[0042] In another embodiment of the implantation of a lens according the invention, a lens of similar design as described above is used except that there is no restraining element on the lens. Temporary cycloplegia is induced, and a capsulorrhexis is performed. The lens is implanted while the ciliary body is in a fully relaxed state. The patient is then fully accommodated (i.e., the ciliary body is placed in a contracted state), preferably through pharmacological agents such as pilocarpine. Once the capsular bag is fully annealed (affixed) to the lens periphery, the pharmacological agent promoting accommodation is stopped. Then, as the ciliary body relaxes, the lens is stretched into an elongated shape having less focusing power. Conversely, as accommodation recurs, the lens returns to it resting shape having greater focusing power.
[0043] Alternatively, a fully relaxed lens (i.e., without restraining element) can be coupled to a fully stressed and contracted ciliary body.
[0044] The intraocular lens systems described above operates to provide accommodation through a change in shape in and position of the optic resulting from an equilibrium of the anatomical forces and the forces in the lens.
[0045] The intraocular lens of the invention is compatible with modern cataract surgery techniques and allows for large increases in optical power of the implanted lens. Unlike other proposed accommodating intraocular lens systems, the lens utilizes a change in shape in addition to axial displacement of the lens. In addition, the fully polymerized silicone materials of the lens are safe to use, eliminating various factors from the prior art, including potential tissue irritation, damage and vision impairment, and significant hurdles from regulatory authorities.
[0046] There have been described and illustrated herein embodiments of an intraocular lens. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Thus, while silicone is the preferred material for all components of the lens, it is appreciated that other polymers, such as acrylics can also be used. In addition, particularly where other materials are used, a different range of durometers for each of the first and second optic layers can be used. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as claimed. | An intraocular lens has a polymeric optic defined by a harder posterior layer and a softer anterior layer. Haptics having a fulcrum attached to the posterior layer and a resistance arm attached to the anterior layer are provided. A bias is provided to the haptic to rotate the haptics about the fulcrum and cause the resistance arm to deform the softer anterior layer about the harder posterior layer to increase the optical power of the lens. As the haptic rotates, it axially displaces the optic anteriorly to additionally increase the optical power. The optical power is adjustable in response to stresses induced by the eye. The haptics are subject to a pre-bias that urges the haptics to rotate or bend about the fulcrum. Temporary restraints are provided to the haptics to retain a stressed shape of the lens against the bias during a post-implantation healing period. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/782,708, filed Mar. 14, 2013, and Ser. No. 61/880,977, filed Sep. 22, 2013, both entitled ENERGY ABSORBING LATCH SYSTEMS AND METHODS, the disclosures of which are hereby incorporated by reference in their entireties.
BACKGROUND
Exterior doors of homes, office buildings, hotels, apartment buildings, etc. are typically equipped with some means (e.g., a door lock) of securing entry into the building. Interior doors of such buildings may also be equipped with some means of securing the door. Such door lock apparatuses are typically rigid and mechanical and to some extent easily defeated by a sudden and forceful action, such as kicking or shouldering. An average adult male is capable of generating a significant amount of force over an effective area of the door lock while using a violent swift action directed at the door lock. In instances of forced entry through the door, the more direct a strike is directed to the door lock, the more successful a perpetrator is at defeating the door lock, typically.
SUMMARY
According to certain aspects of the present disclosure, a door securing device is adapted to resist significant opening of a door when set to an engaged configuration and is also adapted to allow opening of the door when set to a disengaged configuration. The door securing device includes a base member, a deformable member, a configuration joint, and a catch member. The base member includes a base end and a first joint portion. The deformable member extends along a length between a first end and a second end. The first end includes a second joint portion, and the second end includes a catching portion. The configuration joint is adapted to configure the door securing device in the engaged configuration and is also adapted to configure the door securing device in the disengaged configuration. The configuration joint includes the first joint portion of the base member and the second joint portion of the deformable member. The catch member includes a base end and a catch. The catch is adapted to engage the catching portion of the deformable member, at least when the door securing device is resisting the significant opening of the door. The deformable member is adapted to deform and thereby increase the length of the deformable member at least five percent when resisting the significant opening of the door.
In certain embodiments, the base end of the base member is adapted to mount to a door frame and the base end of the catch member is adapted to mount to a door. The base end of the base member may include at least one fastener hole, and the base end of the catch member may include at least one fastener hole. The base end of the base member may be adapted to be mounted to the door frame with door frame fasteners positioned through the fastener holes of the base member. The base end of the catch member may be adapted to be mounted to the door with door fasteners positioned through the fastener holes of the catch member.
In certain embodiments, the configuration joint is a rotatable joint. The rotatable joint may include at least one hole in the first joint portion of the base member, at least one hole in the second joint portion of the deformable member, and a pin positioned within the holes. The door securing device may further include a spring that urges the deformable member to rotate about an axis of the pin and thereby urges the door securing device toward the engaged configuration. The catch may include a hook. The catching portion may include a loop.
In certain embodiments, the door securing device further includes a shield that is positioned at least partly around the deformable member at least when the door securing device is in the engaged configuration. The shield is adapted to resist cutting and thereby protects the deformable member from the cutting. The length of the deformable member may be free to increase with respect to the shield. The shield may or may not substantially resist the significant opening of the door. The shield may be pivotally mounted to the base member. The rotatable joint may define an axis. The shield may be pivotally mounted to the base member at a pivoting joint that is co-axial with the axis of the rotatable joint. The door securing device may further include a torsion spring that is adapted to urge the deformable member and/or the shield to rotate about the axis of the rotatable joint and thereby urge the door securing device toward the engaged configuration. In certain embodiments, the shield includes a finger pocket that is adapted to facilitate a finger to overcome the torsion spring and thereby position the door securing device in the disengaged configuration. The door securing device may further include a detent that is adapted to resist the torsion spring and thereby retain the door securing device in the disengaged configuration when the detent is engaged.
In certain embodiments, the door securing device further includes a keeper that is adapted to retain the door securing device in the engaged configuration when the door is exposed to alternating loads.
According to other aspects of the present disclosure, a door securing device includes a disengaged configuration, an engaged configuration, an armed configuration, a base member, a deformable member, a configuration joint, and a catch member. The disengaged configuration is adapted to allow opening of a door. The engaged configuration is adapted to resist the opening of the door beyond a predetermined opening of the door. The armed configuration is adapted to automatically transition to the engaged configuration upon the opening of the door reaching the predetermined opening and is adapted to manually transition to the disengaged configuration upon operator manipulation. The base member includes a base end and a first joint portion. The deformable member extends along a length between a first end and a second end. The first end includes a second joint portion, and the second end includes a catching portion. The configuration joint is adapted to configure the door securing device in the disengaged configuration, is adapted to configure the door securing device in the engaged configuration, and is adapted to configure the door securing device in the armed configuration. The configuration joint includes the first joint portion of the base member and the second joint portion of the deformable member. The catch member includes a base end and a catch. The catch is adapted to engage the catching portion of the deformable member, at least when the opening of the door is beyond the predetermined opening of the door. The deformable member is adapted to hyperelastically deform and thereby increase the length of the deformable member when resisting the opening of the door beyond the predetermined opening of the door.
In certain embodiments, the door securing device further includes a keeper that is adapted to retain the door securing device in the engaged configuration when the door is exposed to alternating loads. The keeper may or may not retain the door securing device in the armed configuration. The catching portion may include an end loop that may be trapped by the keeper when the door securing device automatically transitions from the armed configuration to the engaged configuration, upon the opening of the door reaching the predetermined opening. The door securing device may be manually transitioned to the disengaged configuration from the engaged configuration by the operator manipulation of the keeper.
Still other aspects of the present disclosure are directed to a door securing device that is adapted to resist significant opening of a door when set to an engaged configuration and that is also adapted to allow opening of the door when set to a disengaged configuration. The door securing device includes a base member, a deformable member, a rotatable joint, and a catch member. The base member includes a base end and a first joint portion. The deformable member extends along a length between a first end and a second end. The first end includes a second joint portion, and the second end includes a catching portion. The rotatable joint is adapted to configure the door securing device in the engaged configuration and also is adapted to configure the door securing device in the disengaged configuration. The rotatable joint includes the first joint portion of the base member and the second joint portion of the deformable member. The catch member includes a base end and a catch. The catch is adapted to engage the catching portion of the deformable member, at least when the door securing device is resisting the significant opening of the door. The deformable member is adapted to deform and thereby increase the length of the deformable member when resisting the significant opening of the door.
A variety of additional aspects will be set forth in the description that follows. These aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad concepts upon which the embodiments disclosed herein are based.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a deformable latch system according to the principles of the present disclosure;
FIG. 2 is another perspective view of the deformable latch system of FIG. 1 , shown in an armed configuration;
FIG. 3 is a perspective view of the deformable latch system of FIG. 1 , shown in a disengaged configuration;
FIG. 4 is another perspective view of the deformable latch system of FIG. 1 , shown in the disengaged configuration of FIG. 3 ;
FIG. 5 is a front elevation view of the deformable latch system of FIG. 1 ;
FIG. 6 is an enlarged view of FIG. 5 ;
FIG. 7 is a top plan view of the deformable latch system of FIG. 1 ;
FIG. 8 is an enlarged view of FIG. 7 ;
FIG. 9 is an end elevation view of the deformable latch system of FIG. 1 ;
FIG. 10 is an enlarged view of FIG. 9 ;
FIG. 11 is an opposite end elevation view of the deformable latch system of FIG. 1 ;
FIG. 12 is an enlarged view of FIG. 11 ;
FIG. 13 is a partial front elevation view of the deformable latch system of FIG. 1 , shown in the disengaged configuration of FIG. 3 and installed on a door system;
FIG. 14 is a partial cross-sectional plan view of the deformable latch system, shown in the disengaged configuration of FIG. 3 , and the door system of FIG. 13 , as called out at FIG. 13 ;
FIG. 15 is the partial front elevation view of FIG. 13 , but with the deformable latch system shown in the armed configuration of FIG. 2 ;
FIG. 16 is the partial cross-sectional plan view of FIG. 14 , as called out at FIG. 15 , with the deformable latch system shown in the armed configuration of FIG. 2 ;
FIG. 17 is the partial front elevation view of FIG. 13 , but with the deformable latch system shown in an engaged configuration;
FIG. 18 is the partial cross-sectional plan view of FIG. 14 , as called out at FIG. 17 , with the deformable latch system shown in the engaged configuration of FIG. 17 ;
FIG. 19 is the partial front elevation view of FIG. 13 , but with the deformable latch system shown in an energy absorbing configuration;
FIG. 20 is the partial cross-sectional plan view of FIG. 14 , as called out at FIG. 19 , with the deformable latch system shown in the energy absorbing configuration of FIG. 19 ;
FIG. 21 is an exploded perspective view of the deformable latch system of FIG. 1 ;
FIG. 22 is a partial cross-sectional plan view of another deformable latch system according to the principles of the present disclosure;
FIG. 23 is a partial front elevation view of still another deformable latch system according to the principles of the present disclosure, the deformable latch system illustrated with a covering shield in phantom line;
FIG. 24 is a partial cross-sectional plan view of the deformable latch system of FIG. 23 , as called out at FIG. 23 ;
FIG. 25 is an enlarged partial perspective view of a pin and a detent feature of a deformable latch system according to the principles of the present disclosure, the pin shown in an un-depressed configuration and the detent feature shown in an engaged configuration;
FIG. 26 is the enlarged partial perspective view of FIG. 25 , but with the pin shown in a depressed configuration and the detent feature shown in a disengaged configuration;
FIG. 27 is an enlarged perspective view of a spring suitable for use in various deformable latch systems of the present disclosure;
FIG. 28 is a partial front elevation view of yet another deformable latch system according to the principles of the present disclosure;
FIG. 29 is a partial cross-sectional plan view of the deformable latch system of FIG. 28 , as called out at FIG. 28 ;
FIG. 30 is a partial front elevation view of still another deformable latch system according to the principles of the present disclosure;
FIG. 31 is a partial cross-sectional plan view of the deformable latch system of FIG. 30 , as called out at FIG. 30 ;
FIG. 32 is a partial perspective view illustrating the deformable latch system of FIG. 28 and the deformable latch system of FIG. 30 installed on the same door system, the deformable latch systems each shown in an armed configuration;
FIG. 33 is a partial perspective view of the deformable latch system of FIG. 28 and the deformable latch system of FIG. 30 each installed on the same door system of FIG. 32 , the deformable latch systems each shown in a disengaged configuration;
FIG. 34 is a front elevation view of the deformable latch system of FIG. 30 , in the armed configuration of FIG. 32 ;
FIG. 35 is a front elevation view of the deformable latch system of FIG. 28 , in the armed configuration of FIG. 32 ;
FIG. 36 is a perspective view of the deformable latch system of FIG. 30 in the disengaged configuration of FIG. 33 ;
FIG. 37 is a perspective view of the deformable latch system of FIG. 28 in the disengaged configuration of FIG. 33 ;
FIG. 38 is a partial cross-sectional plan view of yet another deformable latch system according to the principles of the present disclosure, the deformable latch system shown in an engaged configuration;
FIG. 39 is a partial front elevation view of the deformable latch system of FIG. 38 shown in an armed configuration, the deformable latch system illustrated with a covering shield in phantom line;
FIG. 40 is a partial plan view of the deformable latch system of FIG. 38 with the covering shield of FIG. 39 in phantom line;
FIG. 41 is a partial front elevation view of the deformable latch system of FIG. 38 illustrated without a shielding cover;
FIG. 42 is a partial cross-sectional plan view of the deformable latch system of FIG. 38 , as called out at FIG. 39 ;
FIG. 43 is a partial front elevation view of still another deformable latch system according to the principles of the present disclosure, the deformable latch system shown in an armed configuration;
FIG. 44 is a partial cross-sectional plan view of the deformable latch system of FIG. 43 , as called out at FIG. 43 ;
FIG. 45 is a perspective view illustrating the deformable latch system of FIG. 43 shown in the armed configuration of FIG. 43 ;
FIG. 46 is a partial cross-sectional plan view of yet another deformable latch system according to the principles of the present disclosure, the deformable latch system shown in an armed configuration;
FIG. 47 is a partial front elevation view of the deformable latch system of FIG. 46 shown in the armed configuration of FIG. 46 and without a shielding cover;
FIG. 48 is a partial cross-sectional plan view of the deformable latch system of FIG. 46 , as called out at FIG. 47 ;
FIG. 49 is a partial perspective view illustrating the deformable latch system of FIG. 46 shown in the armed configuration of FIG. 46 and without a shielding cover;
FIG. 50 is a partial front elevation view of still another deformable latch system according to the principles of the present disclosure, the deformable latch system shown in an armed configuration;
FIG. 51 is a partial cross-sectional plan view of the deformable latch system of FIG. 50 , as called out at FIG. 50 ;
FIG. 52 is a partial perspective view illustrating the deformable latch system of FIG. 50 shown in the armed configuration of FIG. 50 ;
FIG. 53 is a cross-sectional plan view of the deformable latch system of FIG. 50 shown in the armed configuration of FIG. 50 and with a shielding cover;
FIG. 54 is a partial front elevation view of yet another deformable latch system according to the principles of the present disclosure, the deformable latch system shown in an armed configuration and with a covering shield in phantom line;
FIG. 55 is a partial cross-sectional plan view of the deformable latch system of FIG. 54 , as called out at FIG. 54 ;
FIG. 56 is a partial perspective view illustrating the deformable latch system of FIG. 54 shown in the armed configuration of FIG. 54 and with the covering shield in phantom line;
FIG. 57 is a partial front elevation view of still another deformable latch system according to the principles of the present disclosure, the deformable latch system shown in an armed configuration;
FIG. 58 is a partial cross-sectional plan view of the deformable latch system of FIG. 57 , as called out at FIG. 57 ;
FIG. 59 is a partial perspective view illustrating the deformable latch system of FIG. 57 shown in the armed configuration of FIG. 57 ;
FIG. 60 is a partial cross-sectional plan view of the deformable latch system of FIG. 57 shown in the armed configuration of FIG. 57 and with a shielding cover;
FIG. 61 is a partial front elevation view of yet another deformable latch system according to the principles of the present disclosure, the deformable latch system shown in an armed configuration and with a covering shield in phantom line;
FIG. 62 is a partial cross-sectional plan view of the deformable latch system of FIG. 61 , as called out at FIG. 61 ;
FIG. 63 is a partial perspective view illustrating the deformable latch system of FIG. 61 shown in the armed configuration of FIG. 61 and with the covering shield in phantom line;
FIG. 64 is an elevation view of a spring assembly adapted for use with the deformable latch system of FIG. 43 ;
FIG. 65 is a bottom plan view of the spring assembly of FIG. 64 ;
FIG. 66 is a side elevation view of the spring assembly of FIG. 64 ;
FIG. 67 is a perspective view of the spring assembly of FIG. 64 ;
FIG. 68 is another front elevation view of the deformable latch system of FIG. 1 illustrating a detent in a disengaged configuration and a button head of a pin depressed, the deformable latch system shown in the armed configuration of FIG. 2 ;
FIG. 69 is a cross-sectional bottom plan view of the deformable latch system of FIG. 1 , as called out at FIG. 68 , illustrating a male member of the detent of FIG. 68 withdrawn from a female member of the detent;
FIG. 70 is a cross-sectional end elevation view of the deformable latch system of FIG. 1 , as called out at FIG. 68 , illustrating the male member of the detent of FIG. 68 withdrawn from the female member of the detent;
FIG. 71 is the front elevation view of FIG. 68 , but with the detent in an engaged configuration and the button head of the pin un-depressed, the deformable latch system shown in the disengaged configuration of FIG. 3 ;
FIG. 72 is the cross-sectional bottom plan view of FIG. 69 , as called out at FIG. 71 , but illustrating the male member of FIG. 69 caught in the female member of FIG. 69 ;
FIG. 73 is a cross-sectional view, similar to the cross-sectional end elevation view of FIG. 70 , as called out at FIG. 71 , but illustrating the male member of FIG. 69 caught in the female member of FIG. 69 ;
FIG. 74 is an end elevation view of a base of the deformable latch system of FIG. 1 ;
FIG. 75 is a front elevation view of the base of FIG. 74 ;
FIG. 76 is a cross-sectional bottom plan view of the base of FIG. 74 , as called out at FIG. 75 ;
FIG. 77 is a cross-sectional end elevation view of the base of FIG. 74 , as called out at FIG. 75 ;
FIG. 78 is a top plan view of the base of FIG. 74 ;
FIG. 79 is a bottom plan view of the base of FIG. 74 ;
FIG. 80 is a perspective view of the base of FIG. 74 ;
FIG. 81 is a side elevation view of the pin of FIG. 68 ;
FIG. 82 is an enlarged portion of FIG. 81 , as called out at FIG. 81 ;
FIG. 83 is a bottom plan view of the pin of FIG. 81 ;
FIG. 84 is a perspective view of the pin of FIG. 81 ;
FIG. 85 is a rotated front elevation view of a deformable member of the deformable latch system of FIG. 1 ;
FIG. 86 is a cross-sectional plan view of the deformable member of FIG. 85 , as called out at FIG. 85 ;
FIG. 87 is a rotated plan view of the deformable member of FIG. 85 ;
FIG. 88 is a rotated end view of the deformable member of FIG. 85 ;
FIG. 89 is a perspective view of the deformable member of FIG. 85 ;
FIG. 90 is a plan view of a covering shield of the deformable latch system of FIG. 1 ;
FIG. 91 is a rotated end elevation view of the covering shield of FIG. 90 ;
FIG. 92 is a rear elevation view of the covering shield of FIG. 90 ;
FIG. 93 is a front elevation view of the covering shield of FIG. 90 ;
FIG. 94 is an opposite plan view of the covering shield of FIG. 90 ;
FIG. 95 is an enlarged cross-sectional end view of the covering shield of FIG. 90 , as called out at FIG. 90 ;
FIG. 96 is an enlarged perspective view of the covering shield of FIG. 90 ;
FIG. 97 is another enlarged perspective view of the covering shield of FIG. 90 ;
FIG. 98 is a plan view of a catch member of the deformable latch system of FIG. 1 ;
FIG. 99 is a perspective view of the catch member of FIG. 98 ;
FIG. 100 is a perspective view of a catch member adapted for use with the deformable latch system of FIG. 1 according to the principles of the present disclosure;
FIG. 101 is a plan view of the catch member of FIG. 100 ;
FIG. 102 is a front elevation view of the catch member of FIG. 100 ; and
FIG. 103 is an end view of the catch member of FIG. 100 .
DETAILED DESCRIPTION
According to the principles of the present disclosure a deformable latch system 100 , and in particular, a system including an energy absorbing member 140 (e.g., an energy absorbing loop) is effective at preventing entry through a door 200 by dynamic action that is applied to the door 200 . Such dynamic action may include kicking with a foot, shouldering with a shoulder, and ramming with a police-style battering ram. In contrast, typical conventional latch systems and typical conventional bolt-style lock systems are susceptible to failure from application of such dynamic action, thereby allowing entry through the door.
In various embodiments, the energy absorbing member 140 may be made of various energy absorbing materials and/or deformable materials. The energy absorbing materials and/or the deformable materials may include energy absorbing plastics (e.g., polycarbonate, PVC, etc.), energy absorbing rubbers (neoprene, isoprene, etc.), energy absorbing composites, etc. In one embodiment, the energy absorbing member 140 includes 40 durometer EPDM. In another embodiment, the energy absorbing member 140 includes 50 durometer EPDM. In still another embodiment, the energy absorbing member 140 includes 55 durometer natural rubber.
The typical latch systems and the typical bolt-style lock systems are substantially inflexible and have minimal energy absorption qualities. Energy that is applied to the door by the dynamic action is concentrated upon a connection between a latch and a catch in the case of the typical latch system and is concentrated upon a connection between a deadbolt and strikeplate in the case of the typical bolt-style lock system. The typical latch system and the typical bolt-style lock system may be included on the same door and offer a modest amount of improvement in preventing entry as the dynamic action causes failure of both the typical latch system and the typical bolt-style lock system. The failure of the typical latch system and/or the typical bolt-style lock system may or may not occur from failure of the deadbolt and/or the strikeplate, in the case of the typical bolt-style lock system, and/or failure of the latch and/or the catch, in the case of the typical latch system. The failure of the typical latch system and/or the typical bolt-style lock system may or may not occur from failure of connecting structure (e.g. the door, a connection between the door and the bolt-style lock system, a door frame, a connection between the door frame and the bolt-style lock system, a connection between the door and the latch system, a connection between the door frame and the latch system, etc.). As the typical latch system and the typical bolt-style lock system are substantially inflexible, the energy delivered by the dynamic action may result in impact of relatively short time duration and relatively high force levels. The high force levels may cause high stresses to develop in the above-mentioned parts and the high stresses may cause the failure.
In contrast, according to the principles of the present disclosure, the deformable latch system 100 includes the deformable member 140 that is substantially flexible. The energy delivered by the dynamic action may result in impact of relatively long time duration and relatively low force levels. The relatively low force levels may result in lower stresses developing in corresponding parts and the lower stresses may be below a failure point. In addition, the deformable member 140 absorbs the energy delivered by the dynamic action and may dissipate the energy as heat.
The deformable latch system 100 is therefore a device designed to absorb and thwart the concentrated energy of an attempted forced entry through the door 200 or a similar access point. When a perpetrator places a sudden force onto the door, the substantially rigid mechanisms of the typical latch system and/or the typical bolt-style lock system designs often fail due to their inability to absorb the energy. The deformable latch system 100 will, in most cases absorb the energy and return the door 200 to its original position. In cases where there are only substantially rigid mechanisms, repeated blows often weaken (e.g., fatigue, cause crack initiation and crack growth, etc.) the lock/latch assemblies and the door/door frame until a point of failure is reached. The deformable latch system's 100 energy absorption qualities continue to function after repeated blows.
Extensible material is used in the deformable member 140 . In certain embodiments, the extensible material is neoprene and/or isoprene. As depicted, the extensible material may be formed into a loop 148 at a distal end 144 of the deformable member 140 (see FIG. 21 ). A proximal end 142 of the extensible material may be molded (e.g., solidly molded) to a metal (e.g., a steel) pivoting pin 190 secured by a base assembly or a single piece base 191 (e.g., a solid base) including two hinge components 192 (e.g., steel hinge components) that are located on opposing ends 190 A, 190 B of the pin 190 . In certain embodiments, the pivoting pin 190 and the deformable member 140 may rotate and/or translated freely with respect to each other about an axis A (see FIG. 21 ). A spring 180 may be attached between the hinge components 192 and the deformable member 140 and thereby urge the loop 148 of the deformable member 140 to maintain contact with a catch assembly or a catch member 220 (e.g., a single piece catch) in a closed configuration 40 (i.e., a closed position, an armed configuration, etc.).
The catch member 220 is separate from a latch assembly 110 that contains the deformable member 140 . The catch member 220 may be a single piece (e.g., a steel piece, a formed piece, a forged piece, and/or a solid piece, etc.) that includes a shaped catch 226 . The catch member 220 may be secured directly to the door 200 . The catch member 220 may be secured directly to the door 200 at a point close to an edge 202 (i.e., an end) of the door 200 and/or may be immediately adjacent to the latch assembly 110 . The catch 226 may contain an area that is open in a shape of a hook and may be adapted to catch the loop 148 as the door 200 is forced open while the latch assembly 110 is in place. As a force F (see FIGS. 18 and 20 ) is exerted outward from the latch assembly 110 , the flexible loop 148 makes contact with the catch 226 as the door 200 is attempted to be forced open. The energy from the sudden blow is expended, absorbed, and/or dissipated as the deformable material of the deformable member 140 is stretched. The stretching of the deformable material of the deformable member 140 may cause a recoiling effect and urge and/or force the door 200 back to its original position.
A clip 260 (e.g., a thin metal spring clip) may be included on the catch member 220 . A function of the clip 260 begins once a first breach attempt occurs and the latch assembly 110 is engaged. The distal end 144 of the loop 148 of the deformable member 140 engages and is secured in the catch 226 , and the clip 260 will not allow the loop 148 to be released from the catch 226 until an operator manually releases it. A purpose of retaining the loop 148 in the catch 226 is to thwart perpetrators who repeatedly apply dynamic action after the first breach attempt. The clip 260 allows the device 100 to remain in a securing position (i.e., configuration) and allows full engagement after the first breach attempt.
The deformable member 140 may be enclosed in a housing 280 (e.g. a metal housing, a steel housing, a tempered steel housing, etc.) that protects the deformable member 140 from being cut as the door 200 is forced open. If a perpetrator forces the deformable member 140 of the deformable latch system 100 to stretch and thereby creates a gap G (see FIG. 20 ) between the door 200 and a door frame 300 , the housing 280 (i.e., the shield) will thwart efforts by the perpetrator to cut the deformable member 140 (e.g., with a cutting tool inserted through the gap G).
Turning now to FIGS. 21 and 85-89 , the energy absorbing member 140 will be described in detail. The energy absorbing member 140 extends between the proximal end 142 and the distal end 144 . A hole 146 may be included at or adjacent the proximal end 142 . The hole 146 may pivotally mount on the pivoting pin 190 , in certain embodiments. In other embodiments, the proximal end 142 may be molded directly over the pivoting pin 190 . The hole 146 and/or the pivoting pin 190 define the axis A about which the energy absorbing member 140 may pivot. As depicted, the energy absorbing member 140 includes a pair of stretch elements 150 . As depicted, a first stretch element 150 A is at a first side 162 of the deformable member 140 , and a second stretch element 150 B is at a second side 164 of the deformable member 140 . The stretch elements 150 , 150 A, 150 B extend between the proximal end 142 and the distal end 144 . At the distal end 144 , the stretch elements 150 , 150 A, 150 B may transition to the loop 148 . As depicted, a pair of the stretch elements 150 , 150 A, 150 B connect the proximal end 142 to the loop 148 . In other embodiments, a single stretch element 150 may be used. In still other embodiments, more than two of the stretch elements 150 may connect the proximal end 142 to the loop 148 or an equivalent structure adapted to engage the catch member 220 .
As depicted, the energy absorbing member 140 is made of a molded piece of energy absorbing material. The energy absorbing material of the energy absorbing member 140 may be seamless and/or continuous and/or monolithic. As depicted, the energy absorbing material of the energy absorbing member 140 is molded about the proximal end 142 , the stretch elements 150 , and the loop 148 . In other embodiments, the energy absorbing material of the energy absorbing member 140 may be in the stretch elements 150 and may be distinct from the loop 148 and/or the proximal end 142 . In still other embodiments, the energy absorbing material of the energy absorbing member 140 may be in the loop 148 , and the loop 148 may connect to the proximal end 142 either directly or via connecting elements. In yet other embodiments, the energy absorbing material of the energy absorbing member 140 may be distinctly positioned at the proximal end 142 . As depicted, the stretch elements 150 A and 150 B are positioned on opposite sides of an opening 149 . The loop 148 may bound the opening 149 at a distal end of the opening 149 . The opening 149 is adapted to be positioned over the catch 226 of the catch member 220 and thereby allow the energy absorbing member 140 to be freely placed in the closed configuration 40 (i.e., the armed configuration), thereby readying the loop 148 for engagement with the catch 226 of the catch member 220 . The energy absorbing member 140 is further bound by a third side 166 and a fourth side 168 . As depicted, the third side 166 and the fourth side 168 are substantially parallel to each other. As depicted, an enlarged area 170 may be included around the hole 146 . As depicted, the enlarged area 170 is substantially cylindrical and concentric with the hole 146 and/or the pivoting pin 190 .
Turning now to FIGS. 21 and 74-80 , the base 191 will be described in detail. The base 191 includes a mounting flange 193 adapted to interface with a portion of the door frame 300 upon which the base 191 is mounted. As depicted, the mounting flange 193 includes fastener holes 194 adapted to receive fasteners that secure the base 191 to the portion of the door frame 300 . As depicted, the mounting flange 193 includes a central portion 193 C between the pair of hinge components 192 (i.e., mounting members). The mounting flange 193 further includes a first extension 193 A and a second extension 193 B that extend beyond the hinge components 192 . As depicted a fastener hole 194 is included in the central portion 193 C. A fastener hole 194 is also included on the extensions 193 A and 193 B of the mounting flange 193 . The fastener holes 194 are staggered to provide structural stability to the base 191 and to distribute loads from the base 191 to the portion of the door frame 300 .
The central portion 193 C of the mounting flange 193 and the pair of hinge support components 192 may define a channel 195 . The channel 195 may be adapted to receive the proximal end 142 of the energy absorbing member 140 . In particular the first side 162 of the energy absorbing member 140 may engage a first side 192 A of the hinge components 192 , and a second side 192 B of the hinge components 192 may engage the second side 164 of the energy absorbing member 140 . As depicted, the channel 195 contains the energy absorbing member 140 between the first side 162 and the second side 164 . Additional room may be provided between the first hinge component 192 A and the second hinge component 192 B to allow mounting of the spring 180 , mounting of the housing 280 , and/or operation of a detent 187 (described in detail below).
The base 191 further includes pivoting holes 196 . In particular, a pair of the pivoting holes 196 are provided with a first pivoting hole 196 on the first hinge component 192 A and a second pivoting hole 196 positioned on the second hinge component 192 B. The pair of the pivoting holes 196 are substantially coaxial with each other and coaxial with the axis A, when the latch assembly 110 is assembled. As depicted, the pivoting pin 190 mounts within the pivoting holes 196 . In certain embodiments, the pivoting pin 190 may rotate within the pivoting holes 196 . In other embodiments, the pivoting pin 190 may be substantially rotationally fixed within the pivoting holes 196 and may instead rotate within the hole 146 of the energy absorbing member 140 . In certain embodiments, the pivoting pin 190 may translate relative to the pivoting holes 196 about the axis A. In certain embodiments, the pivoting holes 196 may be substantially the same size. In other embodiments, the pivoting holes 196 may be of different sizes. For example, FIGS. 70 and 80 illustrate an embodiment where the first side 192 A of the hinge components 192 includes a larger hole 196 L as the hole 196 , and where the second side 192 B of the hinge components 192 includes a smaller hole 196 S as the hole 196 .
As depicted, the hinge components 192 include a contour 197 opposite the mounting flange 193 . The contour 197 may be provided for stylizing the deformable latch system 100 . The contour 197 may further evenly distribute loads from the pivoting holes 196 to the mounting flange 193 . The contour 197 may also serve to reduce snagging that may otherwise occur if someone's clothes brush up against the base 191 . The extensions 193 A, 193 B may include a contour 198 and thereby define sides of the base 191 . The contour 198 may promote even distribution of loads within the base 191 . The base 191 may extend between a first station 92 and a second station 94 . The first station 92 may thereby define a first end of the base 191 and the second station 94 may thereby define a second end of the base 191 . As illustrated at FIG. 17 , the station 94 of the base 191 may be positioned adjacent an edge 302 of the door frame 300 . The station 92 of the base 191 may be positioned away from the edge 302 of the door frame 300 .
Turning now to FIGS. 4, 21, and 90-97 , the housing 280 will be described in detail. The housing 280 extends between a proximal end 282 and a distal end 284 . A passage 286 extends between the proximal end 282 and the distal end 284 of the housing 280 . The passage 286 may be adapted to allow a substantial portion of the energy absorbing member 140 to reside therein. The passage 286 allows the energy absorbing member 140 to deform and/or stretch therein. The housing 280 further defines a first side 288 and a second side 290 that may generally extend between the proximal end 282 and the distal end 284 . The housing 280 further includes a third side 292 and a fourth side 294 that also generally extend between the proximal end 282 and the distal end 284 . The first side 288 generally defines a first wall 289 . The second side 290 generally defines a second wall 291 . The third side 292 generally defines a third wall 293 . And, the fourth side 294 generally defines a fourth wall 295 . The passage 286 is formed by the walls 289 , 291 , 293 , and 295 . The walls 289 , 291 , 293 , 295 may be seamlessly formed into a tubular structure. As depicted at FIGS. 21, 91, 92, and 95-97 , a seam may be included at one or more of the walls 289 , 291 , 293 , 295 (e.g., the wall 291 , as shown). By including a seam, the housing 280 may be formed of sheet material (e.g., sheet metal). The seam may be left free or may be welded to form the tubular structure.
The first wall 289 may include a finger catch 296 . The finger catch 296 may allow an operator's finger to lift the housing 280 and thereby rotate the housing 280 about the axis A. By rotating the housing 280 about the axis A, the energy absorbing member 140 may also rotate about the axis A. As illustrated at FIGS. 4 and 92 , the second wall 291 includes a relief 297 (e.g., a slot 281 , an opening, etc.). The relief 297 may allow access to the loop 148 of the energy absorbing member 140 and thereby allow the catch 226 to engage the loop 148 as the energy absorbing member 140 and the housing 280 are rotated together from an open configuration 70 (i.e., a disengaged configuration) to the closed configuration 40 (i.e., the armed configuration). The relief 297 may smoothly blend with the distal end 284 and thereby minimize potential for snagging. In addition, a funnel 283 (e.g., a chamfer, a round, a taper, etc.) may be included between the distal end 284 and the relief 297 . As illustrated at FIG. 92 , the funnel 283 may include a first part 283 A and a second part 283 B positioned opposite the relief 297 from each other. The first part 283 A may smoothly transition to a first side 281 A of the slot 281 , and the second part 283 B may smoothly transition to a second side 281 B of the slot 281 . The slot 281 and/or the relief 297 may include a bottom 285 opposite the funnel 283 . The bottom 285 may include a semi-circular shape. The funnel 283 may serve to guide the catch 226 back into the relief 297 after an intrusion load F temporarily stretches the loop 148 such that the catch 226 , or a portion of the catch 226 , becomes positioned outside of the relief 297 . The funnel 283 thereby prevents the catch 226 from becoming caught on the distal end 284 of the housing 280 or on other surfaces of the housing 280 (see FIG. 20 ).
As depicted at FIGS. 16, 18, 22, 24, 38, 40, 42, 46, 53, 55, 60, 62, and 69 , a portion of the catch 226 , 3226 , 6228 (e.g., a portion of the hook 228 ) may be positioned within a portion of the finger catch 296 , at least when the deformable latch system 100 is set to the closed configuration 40 . The portion of the catch 226 may rest upon the portion of the finger catch 296 when the latch assembly 110 is in the closed configuration 40 . The spring 180 may urge the portion of the catch 226 to rest upon the portion of the finger catch 296 . The portions of the catch 226 and the finger catch 296 that interface with each other may be arc shaped and may define a radius. When the latch assembly 110 is moved from the closed configuration 40 (see FIG. 16 ) to the engaged configuration 50 (see FIG. 18 ) by the intrusion load F or other load, the portion of the catch 226 may actuate the portion of the finger catch 296 and thereby move the latch assembly 110 from the closed configuration 40 toward the engaged configuration 50 .
As illustrated at FIGS. 21, 90, and 94-97 , holes 298 are included at the third wall 293 and the fourth wall 295 . The holes 298 are generally aligned with the axis A. A spring attachment 299 is further provided on the housing 280 . The spring attachment 299 may engage the spring 180 and thereby connect the spring 180 to the housing 280 . As depicted, the spring attachment 299 is positioned at the fourth side 294 on the fourth wall 295 adjacent the first wall 289 . As depicted at FIGS. 68-70, 72, 73, 91, and 94-97 , a pair of protrusions 189 ′ (e.g., latches) are positioned at the third wall 293 . In the depicted embodiment, the pair of protrusions 189 ′ are positioned opposite the hole 298 from each other and oriented transverse to the passage 286 . In certain embodiments, the pair of protrusions 189 ′ may serve as portions of the detent 187 (described in detail below).
To assemble the latch assembly 110 , the energy absorbing member 140 may be positioned within the passage 286 of the housing 280 . In particular, the distal end 144 may be inserted within the passage 286 at the proximal end 282 of the housing 280 . The energy absorbing member 140 may then be slid through the passage 286 until the hole 146 of the energy absorbing member 140 aligns with the holes 298 of the housing 280 . The housing 280 , with the energy absorbing member 140 within, may then be positioned within the channel 195 of the base 191 . The spring 180 may further be positioned alongside the fourth side 294 of the housing 280 and adjacent the second hinge component 192 B of the base 191 . A first end 182 of the spring 180 may be engaged with the spring attachment 299 (see FIGS. 21, 90, 93, 96, and 97 ) and a second end 184 of the spring 180 may be engaged with a spring attachment 199 (see FIGS. 77, 79, and 80 ) of the base 191 . A passage 186 through the spring 180 may be aligned with the axis A. Upon alignment and positioning of the energy absorbing member 140 , the housing 280 , and the base 191 , the pivoting pin 190 may be inserted through the pivoting holes 196 of the base 191 , the passage 186 of the spring 180 , and the hole 146 of the energy absorbing member 140 . The pivoting pin 190 may be slid through the holes 196 , 186 , 298 until a head 130 at the first end 190 A of the pivoting pin 190 abuts the first hinge component 192 A of the base 191 . The pivoting pin 190 may then be secured to the latch assembly 110 by a retaining ring 139 (e.g., a snap ring, a circlip, etc.). In the embodiment depicted at FIGS. 21 and 81-84 , the pivoting pin 190 includes a retaining groove 136 that may hold the retaining ring 139 .
The pivoting pin 190 and the associated holes 146 , 196 , 186 , 298 may define a configuration joint 90 . The configuration joint 90 may configure the deformable latch system 100 in the closed configuration 40 (i.e., the armed configuration) and the open configuration 70 (i.e., the disengaged configuration). The closed configuration 40 is illustrated at FIGS. 15 and 16 , and the open configuration 70 is illustrated at FIGS. 13 and 14 . When the deformable latch system 100 is set to the closed configuration 40 (i.e., the armed configuration) and an attempt is made to open the door 200 , the configuration joint 90 may automatically configure the deformable latch system 100 at an engaged configuration 50 (see FIGS. 17 and 18 ) by allowing rotation across the configuration joint 90 . The engaged configuration 50 resists opening of the door 200 beyond a predetermined amount. Furthermore, the configuration joint 90 may allow rotation across the configuration joint 90 as the energy absorbing member 140 stretches into an energy absorbing configuration 60 (see FIGS. 19 and 20 ). The spring 180 may urge the latch assembly 110 toward the engaged configuration 50 and/or the closed configuration 40 (i.e., the armed configuration).
Turning now to FIGS. 21, 98, and 99 , the catch member 220 will be described in detail. The catch member 220 includes a base 230 that is adapted to be mounted to the door 200 . The base 230 extends between a first station 96 and a second station 98 . As depicted at FIG. 17 , the first station 96 is adjacent or at the edge 202 of the door 200 . The second station 98 is spaced away from the edge 202 of the door 200 . As depicted, the station 96 defines a first end of the base 230 , and the second station 98 defines a second end of the base 230 . As depicted, the first station 96 and the second station 98 are substantially parallel to each other. The base 230 may extend between a first side 232 and a second side 234 . The base 230 may include a plurality of mounting holes 236 . Fasteners may be inserted through the mounting holes 236 and thereby attach the catch member 220 to the door 200 . As depicted, the holes 236 are spaced from each other at four corners of the base 230 and thereby provide structural stability to the catch member 220 .
The catch 226 extends from the base 230 at or near a center of the base 230 between the first side 232 and the second side 234 . As depicted, the catch 226 includes a hook 228 adapted to engage the loop 148 of the energy absorbing member 140 . As depicted, the catch 226 extends from a first end 227 , integral with the base 230 , to a second end 229 . The hook 228 may open inwardly toward the second station 98 . As the hook 228 extends from the first end 227 , the hook 228 may arch over and beyond the first station 96 . In certain embodiments, the hook 228 arches around an angle of about 180 degrees. The hook 228 may thereby include a shape of a semi-circle. As illustrated at FIG. 98 , the hook 228 may extend back inwardly beyond a central axis of the hook 228 (e.g., beyond 180 degrees of wrap) by an angle α. The angle α may be greater than about 5 degrees, in certain embodiments. In other embodiments, the angle α may be greater than about 1 degree.
As mentioned above, the catch member 220 may further include a clip 260 . As illustrated at FIG. 21 , the clip 260 extends between a first end 262 , mounted to the base 230 , and a second end 264 . The second end 264 may slightly overlap the end 229 of the hook 228 , in certain embodiments. In other embodiments, the second end 264 may be spaced from the end 229 of the hook 228 (see FIG. 98 ). The clip 260 may be made of a spring material (e.g., a spring steel). The clip 260 may apply a slight preload between the end 264 of the clip 260 and the end 229 of the catch 226 . The catch 226 and/or the clip 260 may extend across a width narrower than the opening 149 of the energy absorbing member 140 . As described above, when the loop 148 moves toward the engaged configuration 50 , the clip 260 is depressed to an open position 260 o and thereby allows the loop 148 to enter the hook 228 (see FIGS. 98 and 99 ). Upon entering the hook 228 , the energy absorbing member 140 may transfer tensile loads between the base 191 and the catch member 220 . In transferring the tensile loads, the energy absorbing member 140 stretches along a length 141 of the energy absorbing member 140 and thereby absorbs energy (see FIG. 21 ). Upon entrance of the energy absorbing member 140 into the hook 228 , the clip 260 may return to a closed position 260 c (i.e., a blocking position), with the end 264 of the clip 260 abutting or adjacent to the end 229 of the hook 228 . By returning, the clip 260 may trap the loop 148 and thereby prevent unhooking of the loop 148 from the hook 228 until an operator depresses (i.e., manipulates) the clip 260 .
Turning now to FIGS. 100-103 , a catch assembly 220 ′ is illustrated according to the principles of the present disclosure. The catch assembly 220 ′ is similar to the catch member 220 (i.e., the catch assembly 220 ) described in detail above. As with the catch member 220 , the catch assembly 220 ′ may be secured directly to the door 200 by inserting fasteners through mounting holes 236 at a base 230 ′ of the catch assembly 220 ′. The catch assembly 220 ′ similarly includes a catch 226 ′ that is adapted to catch the loop 148 of the deformable member 140 . The catch assembly 220 ′ may be used with the deformable latch systems 100 , 600 , 1200 , 1400 , 1500 , 1600 , 1700 , 1800 , and 1900 , described herein. As described above, with regard to the catch member 220 , the catch assembly 220 ′ extends between a first station 96 and a second station 98 at the base 230 ′. Likewise, the catch 226 ′ may extend beyond the first station 96 . In the depicted embodiments, the catch assembly 220 ′ mounts on the door 200 , and the latch assembly 110 mounts on the door frame 300 . In alternative embodiments, the catch assembly 220 ′ may mount on the door frame 300 , and the latch assembly 110 may mount on the door 200 . As with the catch 226 of the catch member 220 , a portion of the catch 226 ′ may be positioned in the finger catch 296 of the housing 280 , when the deformable latch system 100 is set to the closed configuration 40 (see FIG. 16 ).
As depicted at FIG. 103 , the catch assembly 220 ′ defines a T shape 244 ′. The T shape 244 ′ is formed by an intersection of a catch leg 246 ′ of the catch assembly 220 ′ with the base 230 ′. The base 230 ′ is thereby divided by the catch leg 246 ′. The base 230 ′ thereby includes a first extension 230 A′ and a second extension 230 B′. As depicted, the extensions 230 A′ and 230 B′ are substantially symmetric to each other about the catch leg 246 ′. As depicted, a pair of the mounting holes 236 is positioned at the first extension 230 A′ and another pair of the mounting holes 236 is positioned at the second extension 230 B′. Fillets may be included between the catch leg 246 ′ and the extensions 230 A′ and 230 B′ for added strength and aesthetics.
The catch leg 246 ′ substantially defines the catch 226 ′. The catch leg 246 ′ and the catch 226 ′ define a width Wc. The width Wc is sized to fit within the opening 149 of the energy absorbing member 140 . Turning now to FIG. 101 , the catch 226 ′ includes an end 229 ′. The end 229 ′ terminates an extension portion 226 e ′ of the catch 226 ′. As depicted, the extension portion 226 e ′ extends substantially parallel to the base 230 ′. As will be described hereinafter, the extension portion 226 e ′ allows additional movement of the loop 148 when captured by the catch assembly 220 ′. As depicted, the extension portion 226 e ′ tangentially blends with a hook portion 226 h ′ of the catch 226 ′. The hook portion 226 h ′ is similar to the hook 228 of the catch 226 , described above. As depicted, the hook portion 226 h ′ may extend around a center of the hook portion 226 h ′ about an arc of approximately 180 degrees. In the depicted embodiment, the arc is approximately 5 to 10 degrees less than 180 degrees. The hook portion 226 h ′ tangentially blends with a base portion 226 b ′ of the catch 226 ′. The base portion 226 b ′ includes a gently curved portion that tangentially blends with an interior of the hook portion 226 h ′. The base portion 226 b ′ extends above the base 230 ′ and thereby provides the base 230 ′ with a stiffening spine. The base portion 226 b ′ further smoothly transfers loads applied to the hook portion 226 h ′ to the base 230 ′. The smooth transitioning between the hook portion 226 h ′, the base portion 226 b ′, and the base 230 ′ relieves certain stress concentrations that would otherwise develop and/or allows for efficient use of material giving a sleek and aesthetic look. Opposite the hook portion 226 h ′, the base portion 226 b ′ continues and tangentially blends with a tail portion 226 t ′. The tail portion 226 t ′ extends substantially above the base 230 ′. In the depicted embodiment, the tail portion 226 t ′ extends beyond the center of the hook portion 226 h ′ above the base 230 ′. As depicted, the base portion 226 b ′ and the tail portion 226 t ′ form an integral connection 227 ′ with the base 230 ′. As depicted, the hook portion 226 h ′ is integrally joined to and continues from the base portion 226 b ′. As depicted, the catch 226 ′, including the base portion 226 b ′, the extension portion 226 e ′, the hook portion 226 h ′, and the tail portion 226 t ′, are formed of a single monolithic piece of material. In other embodiments, one or more of the base portion 226 b ′, the extension portion 226 e ′, the hook portion 226 h ′, and/or the tail portion 226 t ′ may be formed of separate piece(s). The material used in the catch 226 ′ may be steel, brass, stainless steel, aluminum, composite, plastic, and/or other suitably strong material.
As illustrated at FIGS. 100 and 101 , the catch assembly 220 ′ further includes a clip 260 ′. The clip 260 ′ extends between a first end 262 ′ and a second end 264 ′. As depicted, the first end 262 ′ of the clip 260 ′ is attached to an elevated portion of the tail portion 226 t ′ of the catch 226 ′. The clip 260 ′ extends as a cantilever from the first end 262 ′ to the second end 264 ′. As depicted, the second end 264 ′ of the clip 260 ′ contacts the extension portion 226 e ′ of the catch 226 ′ at or near the end 229 ′ of the catch 226 ′. As depicted, the second end 264 ′ of the clip 260 ′ is positioned at an inside of the extension portion 226 e ′. The second end 264 ′ of the clip 260 ′ therefore receives bearing support from the catch 226 ′ when loaded outwardly. In certain embodiments, the bearing support may keep the clip 260 ′ from bending out of the catch 226 ′. As depicted, the clip 260 ′ is made of a thin material that allows the second end 264 ′ of the clip 260 ′ to be elastically deformed toward the base portion 226 b ′ of the catch 226 ′. As the clip 260 ′ is elastically deformed, removing the deforming load from the clip 260 ′ restores the clip 260 ′ to a closed position 260 c ′, illustrated at FIG. 101 . In certain embodiments, the second end 264 ′ of the clip 260 ′ may preload against the extension portion 226 e ′ of the catch 226 ′.
The catch assembly 220 ′ forms a closed loop 240 ′ when the second end 264 ′ of the clip 260 ′ contacts the extension portion 226 e ′. The closed loop 240 ′ may capture the loop 148 of the energy absorbing member 140 . The loop 148 may enter the closed loop 240 ′ when the second end 264 ′ of the clip 260 ′ is bent downwardly toward the base portion 226 b ′ thereby opening the closed loop 240 ′. Likewise, the loop 148 may be removed from the closed loop 240 ′ by bending the second end 264 ′ downwardly.
Operation of the catch assembly 220 ′ will now be described in the context of the catch member 220 and the clip 260 . In particular, FIGS. 13-20 show a sequence of configurations of the door 200 , the catch member 220 , the clip 260 , the latch assembly 110 , and the door frame 300 . In the description that follows, the catch member 220 and the clip 260 are replaced by the catch assembly 220 ′. The open configuration 70 (i.e., the disengaged configuration) is illustrated at FIGS. 13 and 14 . In this configuration, the deformable latch system 100 does not interfere with conventional operation of the door 200 . As further described below, the detent 187 may hold the latch assembly 110 at the open configuration 70 . Holding the latch assembly 110 at the open configuration 70 prevents the door 200 from closing on top of the latch assembly 110 by keeping the latch assembly 110 out of an opening of the door frame 300 .
Upon desiring the door 200 to remain securely closed, an occupant may depress the head 130 of the pin 190 and thereby release the detent 187 . The occupant may also release the detent 187 by other means. Upon the detent 187 being released, the latch assembly 110 is automatically reconfigured to the closed configuration 40 (i.e., the armed configuration) as illustrated at FIGS. 15 and 16 . The spring 180 rotates the energy absorbing member 140 about the axis A and thereby positions the extension portion 226 e ′ and the hook portion 226 h ′ through the opening 149 of the energy absorbing member 140 . As depicted, the spring 180 may be sized such that as the loop 148 rotates toward the door 200 , the loop 148 overpowers the clip 260 ′ and thereby allows the loop 148 to enter the catch 226 ′. As illustrated at FIG. 16 , the clip 260 is bent toward the door 200 by the loop 148 powered by the spring 180 . Likewise, the clip 260 ′ and, in particular, the second end 264 ′ of the clip 260 ′ may be moved toward the door 200 and thereby allow the latch assembly 110 to be configured in the armed configuration 40 . If no opening of the door 200 subsequently occurs, the latch assembly 110 may be reconfigured from the armed configuration 40 to the open configuration 70 of FIG. 14 by merely rotating the housing 280 into position and thereby allowing the detent 187 to reengage. The finger catch 296 may be used to rotate the housing 280 and thereby position the latch assembly 110 at the open configuration 70 .
However, if an attempt is made to open the door 200 with the latch assembly 110 in the armed configuration 40 , the latch assembly 110 moves to the engaged configuration 50 , as illustrated at FIGS. 17 and 18 . By moving to the engaged configuration 50 , the clip 260 , 260 ′ may move away from the door 200 and sit on top of the loop 148 . Likewise, upon the latch assembly 110 moving to the engaged configuration 50 , the loop 148 is pulled deep into the hook portion 226 h ′ of the catch assembly 220 ′. The loop 148 is thereby moved out of the way of the second end 264 ′ of the clip 260 ′, and the clip 260 ′ moves away from the door 200 with the second end 264 ′ of the clip 260 ′ contacting the extension portion 226 e ′ of the catch 226 ′. Thus, in the engaged configuration 50 , the closed loop 240 ′ is formed with the loop 148 of the energy absorbing member 140 trapped inside.
A perpetrator may attempt to untrap the loop 148 from the loop 240 ′ by repeatedly shaking the door 200 . However, this merely results in the latch assembly 110 staying in the engaged configuration 50 with the clip 260 ′ continuing to trap the loop 148 within the closed loop 240 ′. If the intrusion load F is applied to the door 200 , the latch assembly 110 may move to the energy absorbing configuration 60 , as illustrated at FIGS. 19 and 20 . However, the energy absorbing configuration 60 and the engaged configuration 50 are related in that the loop 148 continues to be trapped within the closed loop 240 ′. The energy absorbing configuration 60 may be a subset of the engaged configuration 50 . If the door 200 is brought into contact with the door frame 300 (i.e., if the door 200 is closed), the loop 148 merely moves between the hook portion 226 h ′ and the tail portion 226 t ′ of the catch 226 ′ with the clip 260 ′ blocking removal of the loop 148 from the catch 226 ′.
Upon the intrusion attack on the door 200 ceasing, or upon inadvertent opening of the door 200 with the latch assembly 110 set to the armed configuration 40 , the latch assembly 110 may be returned to the open configuration 70 by the occupant manually releasing the loop 148 from the closed loop 240 ′. In particular, the door 200 may be opened slightly to the engaged configuration 50 , as illustrated at FIG. 18 . This positions the loop 148 into contact with the hook portion 226 h ′. As the loop 148 is deep within the hook portion 226 h ′ and the extension portion 226 e ′, the clip 260 ′ may be bent toward the door 200 forming an opening between the second end 264 ′ of the clip 260 ′ and the end 229 ′ of the catch 226 ′. By closing the door 200 while continuing to depress the clip 260 ′, the loop 148 will exit the opening and may further exit the catch 226 ′. The occupant may further fully rotate the latch assembly 110 toward the open configuration 70 and allow the detent 187 to maintain that position. The occupant may manipulate the clip 260 ′ by pressing a finger on a medial portion of the clip 260 ′ between the first end 262 ′ and the second end 264 ′ of the clip 260 ′.
Turning now to FIG. 22 , another embodiment of a deformable latch system 1200 is illustrated according to the principles of the present disclosure. The deformable latch system 1200 is substantially similar to the deformable latch system 100 , described above. However, an alternative cover 2280 (i.e., an alternative housing) replaces the housing 280 of the deformable latch system 100 . Thus, deformable latch systems, according to the principles of the present disclosure, may include a variety of styles. The variety of styles may include ornamental differences to match various decors.
Turning now to FIGS. 23 and 24 , another embodiment of a deformable latch system 1300 is illustrated according to the principles of the present disclosure. The deformable latch system 1300 also includes many elements and features similar to the deformable latch system 100 . However, a catch 3226 replaces the catch 226 of the deformable latch system 100 . As illustrated, the catch 3226 includes a ball structure 3228 that traps a loop 3148 . In addition, clipping features 3260 are included on an energy absorbing member 3140 that may retain the energy absorbing member 3140 on the catch member 3220 . The clipping members 3260 may resist disengagement of a catch member 3220 and the energy absorbing member 3140 when the door 200 is shaken or otherwise cyclically loaded.
Turning now to FIGS. 25, 26, and 68-73 , the deformable latch system 100 (i.e., the door securing device) may further include the detent 187 that is adapted to resist the spring 180 (e.g., the torsion spring) and thereby retain the deformable latch system 100 in the open configuration 70 (i.e., the disengaged configuration) when the detent 187 is engaged (e.g., in a latched configuration 52 ). FIGS. 25 and 71-73 illustrate the detent 187 engaged and in the latched configuration 52 (with the deformable latch system 100 in the open configuration 70 ), and FIGS. 26 and 68-70 illustrate the detent 187 disengaged in an unlatched configuration 42 (with the deformable latch system 100 in the closed configuration 40 ). In the depicted embodiment of FIGS. 25 and 26 , the base 191 includes a catch 188 , and the housing 280 includes a latch 189 . In the depicted embodiment of FIGS. 68-73 , the base 191 includes a catch 188 ′ (e.g., a pair of holes), and the housing 280 includes the latch 189 ′. The catch 188 ′ may be oriented relative to the mounting flange 193 by an angle β (see FIG. 78 ) and thereby retain the deformable latch system 100 at a desired rotational orientation when at the open configuration 70 .
The deformable latch system 100 may include stop features to locate the housing 280 and the energy absorbing member 140 when the deformable latch system 100 is at the open configuration 70 . The stop features may position the housing 280 about the axis A at or near a rotational position that aligns the latch 189 , 189 ′ and the catch 188 , 188 ′. The stop features may thereby aid the engagement of the detent 187 . In the depicted embodiment, the base 191 includes a stop 185 with a stop surface 185 s (see FIGS. 69, 72, 74-77, and 80 ). The stop surface 185 s is spaced from the axis A by a distance Ds (see FIG. 76 ). The stop surface 185 s may be substantially perpendicular to the angle β (see FIG. 78 ) as defined by the catch 188 ′. The stop surface 185 s may be substantially perpendicular to the catch 188 , 188 ′. The stop 185 may be joined to the first side 192 A of the hinge components 192 and to the mounting flange 193 . As the housing 280 is rotated about the axis A as the deformable latch system 100 is moved toward the open configuration 70 , the stop surface 185 s contacts a portion of the first wall 289 of the housing 280 and stops further movement.
The spring 180 may urge the latch 189 , 189 ′ toward the catch 188 , 188 ′ along a direction parallel to the axis A (see FIG. 21 ). The spring 180 may carry a compression load that urges the latch 189 , 189 ′ toward the catch 188 , 188 ′. When the latch 189 , 189 ′ and the catch 188 , 188 ′ align (e.g., when the deformable latch system 100 is manually moved to the open configuration 70 ), the spring 180 may move and/or hold the latch 189 , 189 ′ into the catch 188 , 188 ′. The latch 189 , 189 ′ may be moved out of the catch 188 , 188 ′ by overpowering the spring 180 . When the deformable latch system 100 is held in the open configuration 70 by the detent 187 , the deformable latch system 100 may be deactivated (i.e., may not secure the door 200 until reactivate by releasing the detent 187 ).
In the depicted embodiments, the detent 187 may be released and the deformable latch system 100 may be reactivated by pressing the head 130 (i.e., a button) of the pin 190 . In particular, the head 130 of the pin 190 is at the first end 190 A of the pin 190 . By pressing the head 130 , the latch 189 , 189 ′ may be moved away from and disengaged from the catch 188 , 188 ′. Upon the latch 189 , 189 ′ disengaging the catch 188 , 188 ′, the spring 180 may rotationally move the deformable latch system 100 from the open configuration 70 to the closed configuration 40 .
In the depicted embodiments, the head 130 is button shaped and extends from an outer surface 131 to an inner surface 132 (see FIGS. 81 and 82 ). As depicted, a first diameter portion 133 of the pin 190 may extend from the inner surface 132 of the head 130 to a shoulder 134 of the pin 190 . The first diameter portion 133 may be sized for the hole 196 L. As depicted, a second diameter portion 135 of the pin 190 may extend from the shoulder 134 to the retaining groove 136 of the pin 190 and again from the retaining groove 136 to an alignment chamfer 137 at the second end 190 B of the pin 190 . The second diameter portion 135 may be sized for the hole 196 S.
In the depicted embodiments, the spring 180 is in compression and thereby urges the fourth wall 295 away from the second side 192 B of the hinge components 192 . The urging of the fourth wall 295 away from the second side 192 B correspondingly urges the third wall 293 toward the first side 192 A of the hinge components 192 . As the latch 189 , 189 ′ is positioned at the third wall 293 and the catch 188 , 188 ′ is positioned at the first side 192 A, the urging together of the third wall 293 toward the first side 192 A also urges together the latch 189 , 189 ′ and the catch 188 , 188 ′. The protrusion of the latch 189 , 189 ′ may rest against the first side 192 A when not engaged with the catch 188 , 188 ′. Upon the latch 189 , 189 ′ and the catch 188 , 188 ′ aligning (e.g., see FIGS. 72 and 73 ), the spring 180 extends, the latch 189 , 189 ′ enters the catch 188 , 188 ′, and the third wall 293 moves toward the first side 192 A. Thus, when the operator rotationally moves the deformable latch system 100 to the open configuration 70 , the detent 187 automatically engages and holds the deformable latch system 100 at the open configuration 70 .
As depicted, the shoulder 134 of the pin 190 bears against the third wall 293 . Thus, when the spring 180 extends, the shoulder 134 (and thereby the pin 190 ) may also move with the third wall 293 . As illustrated at FIGS. 71 and 73 , with the spring 180 extended and the latch 189 , 189 ′ positioned within the catch 188 , 188 ′, the head 130 of the pin 190 is spaced away from the first side 192 A.
By pressing the head 130 of the pin 190 toward the first side 192 A, the spring 180 may be overpowered in compression and the detent 187 released. In particular, pressing the pin 190 toward the first side 192 A causes the shoulder 134 of the pin 190 to press against the third wall 293 . The fourth wall 295 correspondingly compresses the spring 180 against the second side 192 B of the hinge components 192 . By pressing the head 130 of the pin 190 toward the first side 192 A, the third wall 293 is moved away from the first side 192 A, and the latch 189 , 189 ′ disengages from the catch 188 , 188 ′. As the spring 180 is in torsion, the spring 180 urges the deformable latch system 100 from the open configuration 70 to the closed configuration 40 . Thus, when the operator presses the head 130 of the pin 190 toward the first side 192 A, the deformable latch system 100 automatically moves from the open configuration 70 to the closed configuration 40 .
In the depicted embodiment, the spring 180 both biases the housing 280 and/or the latch assembly 110 toward the closed configuration 40 and toward the catch 188 , 188 ′. The spring 180 biases the housing 280 and/or the latch assembly 110 linearly along the axis A (see FIG. 21 ) toward the catch 188 , 188 ′. The housing 280 and/or the latch assembly 110 may linearly slide on the pin 190 along the axis A to and from the catch 188 , 188 ′. The spring 180 may be overpowered by manually urging the housing 280 and/or the latch assembly 110 away from the catch 188 , 188 ′ (e.g., linearly away from the catch 188 , 188 ′). The spring 180 may therefore both urge the latch assembly 110 and/or the housing 280 toward the engaged configuration 50 and/or the closed configuration 40 (e.g., rotationally) and the latch 189 , 189 ′ toward the catch 188 , 188 ′ (e.g., linearly). In other embodiments, separate springs may be used to urge the latch assembly 110 and/or the housing 280 toward the engaged configuration 50 and/or the closed configuration 40 (e.g., rotationally) and the latch 189 , 189 ′ toward the catch 188 , 188 ′ (e.g., linearly).
The detent 187 and/or a similar detent may be implemented with the various latch systems 100 , 400 , 500 , 600 , 1200 , 1300 , 1400 , 1500 , 1600 , 1700 , 1800 , and/or 1900 described herein.
Turning now to FIGS. 28 and 29 , still another embodiment of a deformable latch system 400 according to the principles of the present disclosure is illustrated. The deformable latch system 400 is similar to the deformable latch system 100 . However, the housing 280 is replaced with a slide rail 4280 that guides and protects an energy absorbing member 4140 . The deformable latch system 400 further includes a ball engagement structure similar to the ball structure 3228 of the deformable latch system 1300 . FIGS. 32 and 33 illustrate the deformable latch system 400 in the closed configuration 40 and in the open configuration 70 . As the rail 4280 is rotated between the closed configuration 40 and the open configuration 70 , the energy absorbing member 4140 is also moved about the pivoting pin 190 . Upon an intrusion load F being placed upon the door 200 , a distal end 4144 slides along the rail 4280 and is guided by the rail 4280 . Energy is absorbed as the deformable member 4140 is stretched. The rail 4280 may further provide protection from cutting of the energy absorbing member 4140 .
Turning now to FIGS. 30 and 31 , yet another embodiment of a deformable latch system 500 is illustrated according to the principles of the present disclosure. The deformable latch system 500 is similar to the deformable latch system 400 except that a distal end 5144 of an energy absorbing member 5140 includes guiding features that are external to a rail 5280 . The rail 5280 therefor may omit internal guiding features found on the rail 4280 .
Turning now to FIGS. 38-42 , still another embodiment of a deformable latch system 600 is illustrated according to the principles of the present disclosure. The deformable latch system 600 is similar to the deformable latch system 100 . However, the energy absorbing member 6140 further includes a gripping portion 6160 at a distal end 6144 of the energy absorbing member 6140 . The gripping portion 6160 may be used to assist in removing the energy absorbing member 6140 from the catch member 220 . A hook 6228 of the deformable latch system 600 may extend around an angle greater than 180 degrees and thereby form a cusp that traps a loop 6148 within the hook 6228 . An operator may release the loop 6148 from the cusp of the hook 6228 by pulling on the grip 6160 . In addition, a housing 6280 (i.e., a cover) may include a slot that allows the hook 6228 to protrude through the cover 6280 .
The energy absorbing member 140 , 3140 , 4140 , 5140 , 6140 may further include the following materials, either alone or in combination with other material or materials.
Viton Extreme from DuPont
Tetrafluoroethylene Propylene, FEPM
Silicone Rubber, VMQ/PVMQ
Polyurethane Elastomer, AU or EU
Polysulphide Rubber, TR
Perfluoroelastomer, FFKM—known as the DuPont product Kalrez
Hydrogenated Nitrile Rubber, HNBR
Nitrile Butadiene Rubber, NBR
Fluorosilicone, FVMQ
Fluorelastomere, FKM/FPM, also known as Viton Elastomer by DuPont
Ethylene Propylene Copolymer EPM or EPDM
Epichlorhydrin (CO)
Chlorosulphonated Polyethylene (CSM)
Chloronated Polyethylene (CPE)
Ethylene Acrylic, AEM
Alkyl Acrylic copolymer, ACM
Polychloroprene, CR
Chlorobutyl Rubber (CIIR)
Isobutylene-isopropene copolymere (IIR)
Polybutadiene (BR)
Stryrene Butadiene (SBR)
Synthetic cis-polyisoprene (IR)
Natural Cis-Polyisoprene (NR)
In the embodiments described above, a spring material (e.g., spring steel, spring wire, etc.) may be embedded in the deformable member 140 , 3140 , 4140 , 5140 , and/or 6140 . In certain embodiments, the spring material may be a wireform. In certain embodiments, the spring material may be a coil spring. In certain embodiments, the coil spring may operate as a tension coil spring when the intrusion load F is placed upon the door 200 . In certain embodiments, the coil spring may operate as a compression coil spring when the intrusion load F is placed upon the door 200 . By encapsulating (i.e., embedding) the spring material within the deformable member 140 , 3140 , 4140 , 5140 , 6140 , the deformable member 140 , 3140 , 4140 , 5140 , 6140 may provide a smooth and/or aesthetically pleasing appearance, at least when in normal use. Upon the intrusion load F being placed upon the door 200 , the spring material may serve as a reinforcing material to the deformable member 140 , 3140 , 4140 , 5140 , 6140 . In certain embodiments and/or under certain levels of the intrusion load F, the spring material may remain encapsulated in the deformable member 140 , 3140 , 4140 , 5140 , 6140 . In other embodiments, the intrusion load F may result in separation of the spring material from the deformable member 140 , 3140 , 4140 , 5140 , 6140 and energy may be absorbed by the action of the spring material separating from the deformable member 140 , 3140 , 4140 , 5140 , 6140 .
FIGS. 43-67 illustrate additional embodiments of a deformable latch system 1400 , 1500 , 1600 , 1700 , 1800 , and 1900 that are further described below. The deformable latch systems 1400 , 1500 , 1600 , 1700 , 1800 , and/or 1900 are suitable for encapsulation in the various materials listed above.
Turning now to FIGS. 43-45 , the deformable latch system 1400 will be described in detail. The deformable latch system 1400 includes a catch member 220 , a base 191 , and a spring assembly 1440 . The catch member 220 and/or the base 191 may be similar to and/or the same as the catch members and/or the bases described above. As mentioned above, the spring assembly 1440 may be encapsulated in one or more of the materials listed above. In other embodiments, the spring assembly 1440 may be used without encapsulation and/or without a housing (e.g., the housing 280 ).
As depicted, the spring assembly 1440 is a compression spring assembly and is further illustrated at FIGS. 64-67 . By being a compression spring assembly, the spring assembly 1440 places a compression spring 1450 in compression when the intrusion load F is placed upon the door 200 . In certain embodiments, the compression spring 1450 may bottom out upon a certain extension of the spring assembly 1440 being reached. In certain embodiments, the compression spring 1450 includes a substantially linear spring rate over a range of motion. In other embodiments, the compression spring 1450 may include a variable spring rate as the compression spring 1450 is moved about the range of motion. In certain embodiments, the spring rate of the compression spring 1450 may increase as the spring assembly 1440 is stretched by the intrusion load F being placed upon the door 200 . In certain embodiments, the compression spring 1450 may be preloaded (i.e., may include an initial pre-load) when the spring assembly 1440 is at an unloaded (i.e., a minimum extension length) configuration.
As depicted at FIGS. 64-67 , the spring assembly 1440 extends between a first end 1442 and a second end 1444 . At the first end 1442 , the spring assembly 1440 may define a pin-like structure 1446 . The pin structure 1446 may function similar to the pivoting pin 190 , described above, in relation to the base 191 . The second end 1444 of the spring assembly 1440 may define a loop 1448 . In certain embodiments, the loop 1448 may be open and thereby have a form of a hook. The loop 1448 may function similar to or the same as the loop 148 and/or the opening 149 of the energy absorbing member 140 , described above, in relation to the catch member 220 .
The compression spring 1450 extends between a first end 1452 and a second end 1454 . In the depicted embodiment, the spring 1450 includes an opening 1456 that extends between the first end 1452 and the second end 1454 .
The spring assembly 1440 further includes a base member 1460 and a loop member 1480 . As depicted, the base member 1460 includes the pin 1446 of the spring assembly 1440 , and the loop member 1480 includes the loop 1448 of the spring assembly 1440 . In the depicted embodiment, the base member 1460 and the loop member 1480 each reach through the opening 1456 of the spring 1450 and thereby attach to opposite ends 1452 , 1454 of the spring 1450 . In particular, the base member 1460 includes a first end 1462 that corresponds with the first end 1442 of the spring assembly 1440 . The base member 1460 further includes a second end 1464 that attaches to the second end 1454 of the spring 1450 . The loop member 1480 extends between a first end 1482 and a second end 1484 . The second end 1484 of the loop member 1480 corresponds with the second end 1444 of the spring assembly 1440 . The first end 1482 of the loop member 1480 attaches to the first end 1452 of the spring 1450 . As depicted, the base member 1460 and/or the loop member 1480 may be made of a wireform. As depicted, the base member 1460 may include a pair of wireforms.
Turning now to FIGS. 46-49 , the deformable latch system 1500 will be described. The deformable latch system 1500 is similar to the deformable latch system 1400 , described above, in that it includes the catch member 220 and the base 191 . In addition, the deformable latch system 1500 further includes the pivoting pin 190 , the spring 180 , and a spring 1540 . In certain embodiments, the spring 180 and the pivoting pin 190 may also be included on the deformable latch system 1400 . The spring 180 and the pivoting pin 190 are described above and serve a similar purpose in the deformable latch system 1500 . The deformable latch system 1500 may further include the housing 280 , described above. In certain embodiments, the deformable latch system 1400 may also include the housing 280 . The housing 280 may serve a similar purpose in the deformable latch systems 1400 , 1500 , as that described above. In addition, the housing 280 may serve as a guide to the spring 1540 and/or the spring 1450 or the spring assembly 1440 .
As depicted, the spring 1540 extends between a first end 1542 and a second end 1544 . The first end 1542 of the spring 1540 may define an attachment 1546 to the pivoting pin 190 , and the second end 1544 may define a loop 1548 . As depicted, the spring 1540 is a tension spring. As the spring 1540 is a tension spring, the spring 1540 stretches (i.e., extends) when the intrusion load F is placed upon the door 200 . As depicted, the spring 1540 includes two coils joined by the loop 1548 . The spring 1540 may be formed of a single wire wire-form.
Turning now to FIGS. 50-53 , the deformable latch system 1600 will be described. The deformable latch system 1600 is similar to the deformable latch system 1500 . However, the deformable latch system 1600 includes a spring 1640 with differences from the spring 1540 . In particular, the spring 1640 extends between a first end 1642 and a second end 1644 . The second end 1644 includes a loop 1648 with an open hook. The spring 1640 is illustrated with a single coil.
Turning now to FIGS. 54-56 , the deformable latch system 1700 is illustrated. The deformable latch system 1700 is similar to the deformable latch system 1600 but further includes the spring 180 and the housing 280 .
Turning now to FIGS. 57-60 , the deformable latch system 1800 is illustrated. The deformable latch system 1800 is similar to the deformable latch system 1600 . However, the deformable latch system 1800 includes a spring 1840 that is different from the spring 1640 . In particular, the spring 1840 includes a rectangular coil.
Turning now to FIGS. 61-63 , the deformable latch system 1900 will be described. The deformable latch system 1900 is similar to the deformable latch system 1800 . However, the deformable latch system 1900 further includes the housing 280 and the spring 180 .
This application is related to U.S. Provisional Patent Application Ser. No. 61/782,542, filed Mar. 14, 2013, and entitled ENERGY ABSORBING LOCK SYSTEMS AND METHODS which is incorporated herein by reference in its entirety. The subject matter of U.S. Provisional Patent Application Ser. No. 61/782,542 and the subject matter of the present patent application may be used on the same door 200 and/or door frame 300 .
Features of the various embodiments disclosed herein may be mixed and/or matched to form new embodiments according to the principles of the present disclosure, where appropriate. It is understood that doors come in right hand and left hand varieties. Likewise, the deformable latch systems disclosed herein may be configured for right hand or left hand doors. In certain embodiments, the deformable latch systems may be dedicated to work with either a right hand door or a left hand door. In other embodiments, the deformable latch systems may be reconfigurable for use with a right hand door or a left hand door.
Various modifications and alterations of this disclosure will become apparent to those skilled in the art without departing from the scope and spirit of this disclosure, and it should be understood that the scope of this disclosure is not to be unduly limited to the illustrative embodiments set forth herein. | A door latch ( 100, 400, 500, 600, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900 ) resists opening of a door ( 200 ) beyond a predetermined amount when it is engaged and also allows the opening of the door when it is disengaged. The door latch includes a catch ( 220, 220′, 3220 ) and a base ( 191 ) that is connected to a deformable member ( 140, 3140, 4140, 5140, 6140 ) at a joint ( 90 ). The joint configures the door latch and may include a pin ( 190 ). The catch (e.g., a hook) engages a catching portion (e.g., a loop 148, 3148, 6148 ) of the deformable member when engaged. The deformable member may stretch at least five percent when resisting an intrusion load (F) on the door. The base may mount to a door frame ( 300 ), and the catch may mount to the door. A spring ( 180 ) may urge the deformable member toward engagement. A shield ( 280, 2280, 4280, 5280, 6280 ) may protect the deformable member and resist cutting and may pivot with the deformable member urged by the spring. A finger pocket ( 296 ) may be used to overcome the spring. A detent ( 187 ) may retain a disengaged configuration ( 70 ), and a button ( 130 ) on the pin may be depressed to release the detent. A keeper ( 260 ) may retain an engaged configuration ( 50 ), even when the intrusion load alternates. An armed configuration ( 40 ) may automatically transition to the engaged configuration upon the door reaching the predetermined amount and may be manually transitioned to the disengaged configuration upon operator manipulation. The deformable member may hyperelastically deform. | 8 |
FIELD OF THE INVENTION
The present invention relates to a seeding device and more particularly a seeding device which may be mounted behind a tractor to distribute and plant seed carried in a gel or other suspension medium.
BACKGROUND OF THE INVENTION
In many agricultural applications gel seeding is utilized. In gel seeding, seeds carried within a gel-like suspension are distributed for planting. Gel seeding results in certain benefits in that seeds may be pregerminated prior to planting. This provides certain benefits such as the ability to plant seeds earlier than normal, as the seeds are protected by the gel coating. Another benefit to gel seeding is that gel coated seeds may be planted later than normal with the resultant earlier harvest because of the pregermination and a further benefit of gel seeding is the elimination of the need to transplant seedlings grown in a hot house environment to the outdoors.
When gel coating of seeds is utilized particular problems of seeding result in that normal seeding techniques are often not suitable due to the necessity to preserve and protect budding plants and fragile seedlings.
SUMMARY OF THE INVENTION
In a preferred embodiment of the present invention an auger delivers seed carried in a suitable carrier or suspension medium to a delivery system. The speed of the auger, and hence the volume or quantity of seed in suspension delivered, is controlled by adjustment of the auger drive mechanism. In one mode of operation the seeds in suspension are delivered in a steady stream. In another mode of operation the delivery system delivers the seeds in suspension in timed pulsed batches, the frequency of which are controlled by positioning a pulsed delivery mechanism with respect to camming lobes on a drive wheel.
Accordingly, it is an object of the present invention to provide a gel seeding device which simply and economically provides an effective yet safe device to plant seeds suspended in a gel or other fluid suspension in the ground.
A further object of the present invention is to provide such a device having the ability to vary the frequency and volume of gel suspended seeds to accommodate various planting environments.
A still further object of the present invention is to provide a gel seeding device which may deliver either a continuous stream of seeds suspended in a gel or clumps of seed suspended in said gel at variable selected spacings.
BRIEF DESCRIPTION OF THE DRAWING
These and other objects and advantages of the present invention will become more readily apparent after consideration of the following specification in conjunction with the drawings, wherein:
FIG. 1 is an elevational view, partly in section, showing the gel seeding device of the present invention;
FIG. 2 is a top plan view of the device;
FIG. 3 is an elevational view, partly in section, showing the seed distribution mechanism of the present invention;
FIG. 4 is an elevational view, partly in section, showing an alternative embodiment of the present invention;
FIG. 5 is a top plan view of the embodiment shown in FIG. 4; and
FIG. 6 is an elevational view, partly in section, showing the seed distribution mechanism of the embodiment of FIGS. 4 and 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIGS. 1 through 3 of the drawing it is seen that the seed feeding device 10 of the present invention includes a drive wheel 12 having an axle 14 journalled, as at 16, within a support frame 18. The forward end of frame 18 includes suitable provision (not shown) for attachment to a vehicle such as a tractor which rotates wheel 12, in contact with the ground 20 as the propelling vehicle moves in a forward direction.
Seed to be planted, which is suspended in a gel or fluid suspension, is supplied from a suitable reservoir tank 22 having an open end 24 secured within an inlet opening 26 of a distribution housing 28. The seed in the gel suspension is moved under the action of an auger 30 through auger housing 32 to an outlet opening 34 and feed line 36 into a pump bulb 38 fit over feed line 36 where it is temporarily retained prior to dispersion, as will be explained more fully hereinbelow.
The auger drive shaft 40 is journalled through the auger housing 32, as at 42, and includes an extending shaft portion 44 on which is mounted an auger drive wheel 46. A drive plate 48 is provided suitably keyed to axle 14 so that rotation of wheel 12 also rotates drive plate 48. Auger drive wheel 46 is maintained in friction contact with the inside facing surface, as viewed in FIG. 2, of drive plate 48 so that auger 30 is driven upon rotation of wheel 12.
The volume and, hence, the quantity of seed suspended in the gel-like carrier dispensed by the apparatus is controlled by the speed of rotation of auger 30. This most advantageously may be controlled by orientation of drive wheel 46 with respect to its area of contact on drive plate 48. The most radially inward point of contact provides the lowest rate of rotation of drive wheel 46 and auger 30, while the most radially outward point of contact provides the highest rotation rate for auger 30. Accordingly, provision is made to adjust the position of contact of drive wheel 46 against drive plate 48. This control of the auger speed provides a metering function for the auger.
To this end auger housing 32 is made slidably adjustable along frame 18 by securing auger housing 32 to frame 18 by a mounting subassembly 50 secured by a clamping member 52 to frame 18. A suitable clamping bolt 54 securely fixes clamp 52 to frame 18 to position the auger assembly for the desired rate of rotation. Loosening of bolt 54 permits lateral adjustment, as viewed in FIG. 1, of auger housing 32 with respect to frame 18 and drive plate 48 to orient drive wheel 46 in any position from its most radially inward position, illustrated in FIG. 1, to its most radially outward position adjacent the circumference of drive wheel 48. The apparatus is universally adjustable within this range to permit a wide selection of auger speeds to accommodate varying desired flow rates for the seed suspended in the gel carrier.
When a desired flow rate has been selected and the auger housing securely clamped on housing 18, the auger forces the gel carrier through the outlet opening down the feed line 36 where it accumulates in pump bulb 38. Pump bulb 38 is a bulbous reservoir formed of a resilient elastic material, such as rubber, neoprene, or the like and includes a discharge outlet 56 having a discharge opening 58 oriented slightly above the level of the ground 20. Feeding device 10 includes a coulter or plow-like device 60 secured by a mounting shaft 62 to the support frame 18. Coulter 60 is positioned in advance of the discharge opening 58 for the seed suspended in the gel carrier. As the device 10 is moved along a field, the coulter opens up a trough 64 (see FIG. 3) suitable to receive the gel carrier carrying the seed to be planted. The viscosity of the gel is such as to preclude free running of the carrier medium from the discharge opening 58 but the viscosity is such as to allow discharge at an even rate under action of the pressure supplied by the rotating auger 30. A plow-like coverer 65, also mounted to the auger housing backfills the dirt into the trough 64 to cover the newly dispersed seed. Coverer 65 is appropriately secured by a mounting shaft 66.
In another aspect of the invention the seed is delivered in pulsed clumps within the trough 64 under the action of a cam actuated clapper which periodically, at spaced time intervals, strikes the pump bulb to dislodge gel carrier in a sequence of pulsed clumps.
Accordingly, the device is provided with an extended jack shaft 68 secured to frame 18 by a shaft mount 70. Shaft mount 70 includes a through bore 72 within which jack shaft 68 is slidably disposed. A rocker arm assembly 74 is provided and one end 76 of jack shaft 68 is journalled within rocker arm 74 so that the rocker arm 74 may pivot about the axis of jack shaft 68. The upper end 78 of rocker arm 74 includes a cam follower 80 which rides along the exterior facing surface of drive wheel 48. The lower end 82 of rocker arm 74 carries a striker assembly 84 comprising a striking head 84 secured at the end of a threaded bolt 86 which is adjustably threaded within a threaded bore 88 in the lower end 82 of rocker arm 74.
A pivoted clapper paddle member 90 depends from housing 18 and rests against the exterior surface of pump bulb 38. The exterior facing surface of drive plate 48 includes a plurality of radially spaced cam surfaces 92 at discrete circumferentially displaced locations. Each cam surface 92 comprises an outwardly inclined surface 94 terminating in a sharp edge surface 96.
Upon rotation of drive plate 48 with rotation of wheel 12, the inclined surface 94 of a cam surface 92 when it moves into register with cam follower 80 pivots rocker arm 74 forcing striking head 86 against clapper paddle 90. This forces the clapper paddle 90 to pivot inwardly against the exterior surface of pump bulb 38, depressing the resilient bulb in a squeezing action, to eject a measured quantity of gel retained therein in a clump or spurt.
The spacing of the clumps is variable within a predetermined range by adjusting the location of cam follower 80 with respect to different sets of radially spaced cam surfaces 92. Thus the frequency of actuation of the clapper paddle 90 may be controlled by the circumferential spacing of cam surfaces 92 at the same radial location about drive plate 48. As seen in FIG. 1, the radial outermost sets of cam surfaces 92 are more numerous than other radially inward sets due to the greater circumferential extent. Thus, the outermost set of cam surfaces may be utilized for dispersal of seed in the gel carrier medium at the closest interval of spacing, for example 51/2 inches between dispersal points. The sequentially inward sets may be utilized for larger intervals between dispersal points, for example, 61/2, 8, 10, 13 and 19 inches, respectively.
Positioning of cam follower 80 to register with a selected set of cam surfaces 92 is accomplished by moving rocker arm and jack shaft assembly to the appropriate location in the shaft mount 70 and securing the assembly by a pin 96 passing through an access bore 98 in shaft mount 70 and through an access bore 100 in jack shaft 68.
When pulsed delivery of seed is desired, a determination is made as to the desired spacing between pulses and the device is set so that cam follower 80 registers with the proper set of cam surfaces 92 for the selected spacing. When continuous delivery is desired, the device is set so that cam follower 80 is beyond the outer limit of cam surfaces 92 so that there is no actuation of clapper paddle 90.
In both modes of operation further control of the quantity of seed delivered is controlled through the selection of the auger speed by proper positioning of the friction wheel 46 in contact with drive plate 48. In essence, auger 30 acts as a metering device to meter the selected quantity of gel carrying seed through the system.
An alternative embodiment of the present invention is illustrated in FIGS. 4 through 6 of the drawings. A feed conduit or flexible hose 110 is connected to the reservoir tank (such as 22 shown in FIG. 1) which contains the seed suspended in the gel-like carrier. The feed conduit 110 is secured to one end of a 45° elbow 112 by a clamp 113. The other end of the elbow 112 is connected to the intake barrel 114 of the auger assembly 116 by a sleeve 118 and clamps 120. The intake barrel 114 defines the inlet port 122 of the auger assembly into which flows the gel suspension carried in the reservoir. An internal end wall 124 of the intake barrel 114 includes a conically shaped nacelle 126 projecting into the inlet port 122 defined by the barrel. The nacelle 126 improves the flow of the gel suspension into the auger housing 128 of the assembly 116.
The particular embodiment illustrated in FIGS. 4 through 6 of the drawings includes not one auger as shown in the previous embodiment but rather two. A left-hand auger 130, preferably formed of Delrin, a registered trademark of E.I. du Pont de Nemours & Co., Inc., or other synthetic material, and a right-hand auger 132, preferably made of aluminum, rotate with their shafts 134 and 136, respectively, within the auger housing 128. The shafts 134, 136 are journalled through the housing and supported near one end by a bushing plate 138 and at the other end by a wall of the auger housing which also defines the end wall 124 of the intake barrel. The shafts of the augers are parallel and positioned within the housing so that the blades of the augers overlap and intermesh in a cooperating fashion to help propel the gel suspension through the housing to an outlet opening 140.
The shaft 136 on which the right-hand auger 132 is mounted extends through the bushing plate 138. An auger drive wheel 142 is securely mounted by a set screw 144 onto the extended portion 146 and, like the previous embodiment, is positioned to contact the inside facing surface of the cam plate 148. A first gear 150 and a second gear 152 are respectively secured to the left-hand and right-hand auger shafts 134, 136 and situated on their shafts to intermesh with each other. This causes the left-hand auger 130 and right-hand auger 132 to rotate in unison. As with the previous embodiment, the cam plate 148 is keyed to the axle 154 on which the wheel 156 of the seeder is mounted so that rotation of the wheel 156 similarly rotates the cam plate 148. The auger drive wheel 142, which is in frictional contact with the cam plate 148, will also rotate with movement of the gel seeder. This causes the two augers which are gear-linked together to rotate in unison.
The use of double augers in this embodiment as opposed to the single auger of the embodiment illustrated in FIGS. 1 through 3 is advantageous in that the auger housing 128 may be made more compact with the two augers providing the required force to propel the gel suspension through the housing. Also, the use of two closely fitted meshing augers provides a positive displacement action to more accurately meter the gel mixture.
As with the first embodiment described, the volume of gel suspension dispensed by the seeding apparatus shown in FIGS. 4 through 6 is controlled by the speed at which the augers 130, 132 rotate. This can be adjusted by repositioning the auger assembly 116 on the frame 158 of the seeding apparatus. By loosening the wing nuts 160 and clamp bar 162 and block 164 which secure the assembly 116 to the frame, the auger drive wheel 142 can be adjusted to contact the cam plate 148 at various distances from the axle 154 and thus rotate at different selectable rates.
An L-shaped pressure plate 166 is mounted on the frame 158 of the gel seeder. A bore 168 is formed in a side wall 170 of the auger housing 128 adjacent the pressure plate 166. The bore 168 receives a plunger 172 and a spring 174 which outwardly biases the plunger 172 against the pressure plate 166. The pressure of the plunger 172 against the pressure plate 166 forces the auger drive wheel 142 to remain in constant contact with the cam plate 148, thus insuring that the drive wheel 142 will always rotate with the rotation of the cam plate 148.
The gel suspension is forced by the augers through the auger housing 128 to the outlet opening 140 formed therein whereupon it enters the clump pump assembly 176 mounted to the frame below the auger assembly 116. The clump pump assembly 176 includes a pump tube 178 which closely receives the upper portion of a pump nozzle 180. The pump nozzle 180 has a cylindrical shape and includes a bore 182 formed axially through its entire length. The upper end surface 184 of the pump nozzle 180 is countersunk to form a widened inlet opening 186 which receives the flow of gel suspension from the auger assembly 116. The pump nozzle 180 is furnished with a U-shaped boss 188 which extends from a surface of the lower portion of the nozzle. As will become more apparent in the following description, the boss 188 functions to link the nozzle 180 with a pivoting lever plate 190 of the clump pump assembly so that the pivotal movement of the lever plate 190 is translated into a reciprocating motion of the nozzle 180 within the pump tube 178.
As with the embodiment illustrated in FIGS. 1 through 3, a rocker arm assembly 192 is included with this alternative embodiment. The assembly includes a rocker arm 194 which pivots about a jack shaft 196 mounted to the frame 158 of the gel seeder. The position of the rocker arm 194 on the jack shaft 196 can be adjusted by removing a ring pin 198 which holds the rocker arm in place on the shaft 196 and relocating the rocker arm 194 by inserting the ring pin 198 through one of several holes 199 formed diametrically through the shaft. The rocker arm 194 includes a cam follower 200 at its upper end which contacts the cam surfaces 202 protruding from the surface of the cam plate 148. Situated at the lower end of the rocker arm 194 is a striker assembly 204 which includes a striking head 206 secured to the end of a threaded bolt 208. The bolt 208 is received by a threaded bore 210 formed in the rocker arm 194.
As previously mentioned, the clump pump assembly 176 includes a lever plate 190. The lever plate 190 has a planar striking portion 212 and two triangular shaped arms 214 which extend perpendicularly in the same direction from the striking portion 212. Holes are formed in each arm 214 of the lever plate 190 to receive a pin 216 for pivotally mounting the lever plate 190 to the frame 158 of the gel seeder. The arms 214 of the plate are linked to the pump nozzle 180 by a pin 218 which is received between the legs 219 of the U-shaped boss 188 formed on the pump nozzle and through holes formed near the ends of the arms 214 of the lever plate 190.
Wrapped around the pin 216 about which the lever plate pivots is a spring clip 220. One leg 222 of the spring clip 220 is received by a hole 224 formed in the frame 158 of the seeder while the other leg 226 of the spring clip is hooked about an edge 228 of one arm 214 of the lever plate. The spring clip 220 keeps the lever plate 190 biased outwardly from the frame 158 with its striking portion 212 in contact with the head 206 of the striker assembly 204 and biases the pump nozzle 180 in a downwardly extended position within the pump tube 178. The pivotal action of the rocker arm 194 as the cam follower 200 rides up on a cam surface 202 of the cam plate 148 compresses the spring clip 220 and causes the lever plate 190 to move in an arc about the pivot pin 216, as shown by arrow A in FIG. 6 of the drawings. This in turn causes the pump nozzle 180 to slide upwardly within the pump tube 178, as shown by arrow B in the same figure. The reciprocating motion of the pump nozzle 180 within the pump tube 178 dislodges metered amounts of gel suspension filling the pump tube and nozzle. The suspension is dispensed in clumps from the outlet opening 230 of the nozzle 180.
As with the other embodiment, the rocker arm assembly 192 and jack shaft 196 in this alternate embodiment can be positioned at various points on the jack shaft 196 so that the cam follower 200 registers with a selected set of cam surfaces 202. This changes the periodicity at which the gel carrier is dispensed in clumps. The clump pump can be deactivated by moving the cam follower 200 radially outwardly on the cam plate 148 so that it no longer is in register with any cam surfaces 202.
The frame of the gel seeder includes two tubes 232 mounted on its underbody. The tubes 232 receive shafts 234 which are connected to a coulter 236 and coverer 238. Set screws 240 threaded through openings in the tubes 232 hold the coulter 236 and coverer 238 in any selected position relative to the frame 158 and at any desired depth in the ground.
It is thus seen that the present invention provides an effective yet simple device to meter a desired quantity of seed carried in a gel carrier for dispersion during seeding in either a controlled continuous stream or in controlled spaced pulses. The plug mixes on the market today will not clog the gel seeder of the present invention, as they will do with many other seeding devices. The gel seeder can accept, for example, mixes of gel and finely ground peet or gel and fertilizer or other fluid suspensions and distribute these mixes either continuously or in small metered amounts. It is also evident that the invention disclosed herein may be utilized in other applications for the delivery of a fluid in either a continuous stream or pulsed batches. | A seeding device to dispense seed suspended in a gel or other carrier medium in either a continuous stream or discrete pulses. A coulter opens a furrow of earth to the proper depth and seed carried in a gel or other suspension medium is delivered in a pulsed or continuous stream into the furrow which is then covered with earth by a trailing coverer. An auger delivers the seed in suspension and the speed of the auger is controlled to vary the volume of seed and gel or other suspension medium delivered. Circumferentially spaced cam lobes on a drive wheel control the frequency and therefore the row spacing of the seed suspension medium distributed in the pulse delivery mode. | 8 |
BACKGROUND
1. Technical Field
The present disclosure relates to surgical instruments and, more particularly, to methods of measuring conditions of ultrasonic surgical instruments.
2. Background of Related Art
As an alternative to open instruments for use with open surgical procedures, many modern surgeons use endoscopes and endoscopic electrosurgical apparatuses (e.g., endoscopic or laparoscopic forceps) for remotely accessing organs through smaller, puncture-like incisions. These instruments are particularly suited for use in minimally invasive procedures, such as endoscopic or laparoscopic procedures where patients tend to benefit from less scarring, less pain, and reduced healing time. Typically, the endoscopic forceps is inserted into the patient through one or more various types of cannulas or access ports (typically having an opening that ranges from about five millimeters to about fifteen millimeters) that has been made with a trocar; as can be appreciated, smaller cannulas are usually preferred.
Some endoscopic instruments may utilize ultrasound vibrations to effectuate certain medical procedures. In particular, ultrasonic instruments utilize mechanical vibration energy transmitted at ultrasonic frequencies to treat tissue. When transmitted at suitable energy levels, ultrasonic vibrations may be used to coagulate, cauterize, fuse, cut, desiccate, and/or fulgurate tissue to effect hemostasis.
An endoscopic forceps that utilizes ultrasound and is configured for use with small cannulas (e.g., cannulas less than five millimeters) may present design challenges for a manufacturer of endoscopic instruments.
SUMMARY
According to one aspect, a method of measuring conditions of an ultrasonic instrument includes providing an ultrasonic instrument that includes an end effector and a waveguide operably coupled to a generator and the end effector. The waveguide may be curved. The method involves generating one or more pulses with the generator, transmitting the one or more pulses to one or both of the waveguide and the end effector, generating one or more waves that scatter in an interferential pattern in response to the transmission of the one or more pulses, registering a signal indicative of the interferential pattern, generating an actual interferential pattern based upon the signal, and identifying one or more conditions of the end effector based upon the actual interferential pattern.
The method may include providing the ultrasonic instrument with one or more sensors in electrical communication with the generator, registering the signal indicative of the interferential pattern with the sensor, and electrically communicating the signal from the sensor to the generator. The method may involve registering the signal for a predetermined time period, wherein the waveguide defines a predetermined length, wherein sound velocity in the waveguide is predetermined, and wherein the predetermined time period is greater than twice the predetermined length of the waveguide divided by the sound velocity in the waveguide. The method may involve sensing the signal with the generator and registering the signal with the generator.
One step may include positioning the end effector in contact with tissue, wherein the one or more conditions correspond to the interaction of the end effector and the tissue. The one or more conditions may include temperature, mechanical load, and/or relative positioning of the end effector. Each condition has one or more predetermined interferential patterns.
The method may involve adjusting the one or more pulses based upon the one or more conditions. The method may include adjusting the one or more pulses in response to differences between the actual interferential pattern and the one or more predetermined interferential patterns. The method may involve generating a series of pulses with the generator. The method may include providing a memory device operably coupled to the ultrasonic instrument, the memory device including one or more predetermined interferential patterns based upon the one or more conditions and comparing the actual interferential pattern with the one or more predetermined interferential patterns. The method may include calibrating an operating temperature range of the ultrasonic instrument from about room temperature to about three-hundred degrees centigrade.
One aspect of the present disclosure provides a method of measuring conditions of an ultrasonic instrument. The method includes the step of providing an ultrasonic instrument including a housing having a shaft extending therefrom, an end effector operably coupled to a distal end of the shaft, a waveguide operably associated with the shaft, and a transducer operably associated with the waveguide. The waveguide defines a predetermined length. Sound velocity in the waveguide is predetermined. The method involves generating one or more pulses with the transducer, transmitting the one or more pulses to the waveguide, registering one or more ultrasound waves reflected by one or both of the waveguide and the end effector in response to transmission of the one or more pulses, generating an interferential pattern of the one or more registered reflected ultrasound waves, and identifying one or more conditions of the end effector based upon the interferential pattern.
The method may involve the step of positioning the end effector in contact with tissue. The one or more conditions may correspond to the interaction of the end effector and tissue. The one or more conditions may include temperature, mechanical load, and/or positioning of the end effector relative to the shaft.
One step includes registering the one or more ultrasound waves for a predetermined time period that is greater than twice the predetermined length of the waveguide divided by the sound velocity in the waveguide.
The method may include the step of generating a series of pulses with the transducer. One step involves adjusting, the one or more pulses based upon the one or more conditions.
According to another aspect, the method includes providing a memory device operably coupled to the ultrasonic instrument. The memory device includes one or more predetermined interferential patterns based upon the one or more conditions. One step involves comparing the generated interferential pattern of the one or more registered reflected ultrasound waves with the one or more predetermined interferential patterns.
One step may involve calibrating the operating temperature range of the ultrasonic instrument from about room temperature to about three-hundred degrees centigrade.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects and features of the present disclosure will become more apparent in light of the following detailed description when taken in conjunction with the accompanying drawings in which:
FIG. 1 shows a perspective view of one example of an ultrasonic instrument;
FIG. 2 is a block diagram depicting the interaction between an energy source and a transducer assembly of the ultrasonic instrument of FIG. 1 ;
FIG. 3 is a block diagram depicting the transducer assembly of FIG. 2 ;
FIG. 4 shows a perspective view of one embodiment of an ultrasonic instrument in accordance with the principles of the present disclosure;
FIG. 5 is a block diagram depicting the operation of the presently disclosed ultrasonic instrument;
FIG. 6 shows a depiction of a predetermined interferential pattern in accordance with the present disclosure; and
FIG. 7 shows a depiction of an actual interferential pattern produced by the presently disclosed ultrasonic instrument.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Detailed embodiments of the present disclosure are disclosed herein; however, the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure.
In the drawings and in the descriptions that follow, the term “proximal,” as is traditional, will refer to an end which is closer to the user, while the term “distal” will refer to an end that is farther from the user.
With initial reference to FIG. 1 , an embodiment of an ultrasonic instrument 10 (e.g., a forceps) is shown for use with various surgical procedures and generally includes a housing 20 , a transducer assembly 30 , an energy assembly 40 , a shaft assembly 50 , a waveguide assembly 60 , a trigger assembly 70 , a rotating assembly 80 , and an end effector assembly 90 that mutually cooperate to grasp, seal, and divide tubular vessels and vascular tissue.
Ultrasonic instrument 10 is powered by the energy assembly 40 when the energy assembly 40 is operably connected to the ultrasonic instrument 10 . The energy assembly 40 may include one or more batteries 42 and/or one or more electrosurgical cables (not shown) to transfer energy, e.g. voltage from DC and/or AC signals, to the ultrasonic instrument 10 . The ultrasonic instrument 10 may include a smart battery that controls the charge and discharge of its battery cells and communicates with the transducer assembly 30 as illustrated in FIG. 2 .
In embodiments with one or more electrosurgical cables, the ultrasonic instrument 10 is connectable to an external source of electrosurgical energy, e.g., an electrosurgical generator (not shown). One such source of electrosurgical energy is described in commonly-owned U.S. Pat. No. 6,033,399 entitled “ELECTROSURGICAL GENERATOR WITH ADAPTIVE POWER CONTROL.”
The transducer assembly 30 includes one or more ultrasonic transducers 30 a operably coupled to the housing 20 . Each transducer, which may be positioned within the housing 20 , converts the energy transmitted thereto from the energy assembly 40 into high frequency mechanical motion, e.g., ultrasonic vibration. As such, the frequency of the ultrasonic vibration in the one or more transducers is controlled by the frequency of the energy signal, e.g., high voltage AC signal, applied to the one or more transducers. As depicted in FIG. 3 , this frequency control may be accomplished by a phase-lock loop in the transducer assembly 30 .
With reference to FIG. 1 , the shaft assembly 50 , which may be at least partially disposable, includes a shaft 52 which extends from the housing 20 and defines a central lumen 52 a therethrough. The central lumen 52 a receives at least a portion of the waveguide assembly 60 and a drive assembly 54 therein. The drive assembly 54 is operably coupled to the trigger assembly 70 at a proximal end of the drive assembly 54 and is operably coupled to the end effector assembly 90 at a distal end of the drive assembly 54 for operating the end effector assembly 90 upon the actuation of the trigger assembly 70 .
The end effector assembly 90 , which may be at least partially disposable, includes a pair of opposing jaw members 92 , 94 . The first jaw member 92 pivots relative to the second jaw member 94 via the drive assembly 54 upon the actuation of the trigger assembly 70 , positioning jaw members 92 , 94 between approximated (closed) and unapproximated (open) configurations. Second jaw member 94 defines a channel 94 a therethrough.
With continued reference to FIG. 1 , the waveguide assembly 60 is positioned within the shaft 52 of the shaft assembly 50 and is configured to receive and transmit the ultrasonic mechanical vibration generated by the one or more transducers. The waveguide assembly 60 includes a waveguide 62 and an ultrasonic treatment member 64 operably coupled to the distal end of the waveguide 62 . The waveguide assembly 60 is at least partially positionable within one or both jaw members 92 , 94 of the end effector assembly 90 . More particularly, at least a portion of the ultrasonic treatment member 64 is positionable within the channel 94 a defined by jaw member 94 of the end effector assembly 90 . The ultrasonic treatment member 64 is configured to receive the mechanical vibration from the one or more transducers and transmit the mechanical vibration to treat tissue positioned within end effector assembly 90 . The waveguide assembly 60 may be longitudinally translatable with respect to the end effector assembly 90 .
The rotating assembly 80 is operatively connected to the housing 20 and is rotatable in either direction about the longitudinal axis of the shaft assembly 50 to rotate the shaft assembly 50 and the end effector assembly 90 about the longitudinal axis “A” of the shaft assembly 50 . This enables the user to position and re-position the ultrasonic instrument 10 prior to activation and sealing. The rotating assembly 80 is operably coupled to the shaft assembly 50 . A more detailed description of rotating assembly 80 is described in U.S. Pat. No. 7,101,371, entitled “VESSEL SEALER AND DIVIDER” by Dycus et al.
The trigger assembly 70 includes an activation trigger 72 for activating energy from the energy assembly 40 and a clamping trigger 74 for operating the end effector assembly 90 . The trigger assembly 70 is operably coupled to the housing 20 . The activation trigger 72 is configured to facilitate the transmission of the energy from the energy source 42 to the one or more transducers upon the actuation thereof. The clamping trigger 74 is configured to move the drive assembly 54 in order to move the opposing jaw members 92 , 94 between unapproximated and approximated configurations upon the actuation of the clamping trigger 74 . In this manner, the clamping trigger 74 of the trigger assembly 70 is operatively connected to the shaft assembly 50 to impart movement to first and second jaw members 92 , 94 from an unapproximated (open) position, where the jaw members 92 , 94 are in spaced relation relative to one another, to a clamping or approximated (closed) position, where the jaw members 92 , 94 cooperate to grasp tissue therebetween.
In use, when the activation trigger 72 is actuated, the energy assembly 40 applies energy, e.g., the high voltage AC signal, to the transducer assembly 30 . The activation trigger 72 may be configured to operate the ultrasonic instrument 10 in multiple modes of operation, including, but not limited to a low-power mode of operation and a high-power mode of operation. As discussed above, the energy is then converted by the transducer assembly 30 and transmitted from the transducer assembly 30 along the waveguide assembly 60 to the end effector assembly 90 in order to treat tissue grasped between the first and second jaws 92 , 94 with ultrasonic vibrations.
One embodiment of an ultrasonic instrument, generally referred to as 100 , is depicted in FIG. 4 . Ultrasonic instrument 100 is similar to ultrasonic instrument 10 and is described herein only to the extent necessary to describe the differences in construction and operation thereof. In particular, ultrasonic instrument 100 includes a housing 20 having a shaft assembly 50 extending therefrom, an end effector assembly 90 operably coupled to a distal end of the shaft assembly 50 , a waveguide assembly 60 operably associated with the shaft assembly 50 , and a transducer assembly 30 operably associated with the waveguide assembly 60 . The waveguide assembly 60 defines a predetermined length and may be curved. Sound velocity in the waveguide assembly 60 may be predetermined.
Ultrasonic instrument 100 also includes one or more sensors 110 secured thereto that are electrically coupled to the transducer assembly 30 (e.g., via a generator 32 including a microcontroller 34 and/or any suitable electrical, mechanical, and/or electro-mechanical device(s) known in the art). With continued reference to FIG. 4 , a first sensor 110 a is shown positioned on the shaft assembly 50 and a second sensor 110 b is shown positioned on jaw member 94 of end effector assembly 90 . The sensors 110 may be positioned on any suitable portion of the ultrasonic instrument 100 . The sensors 110 are configured to obtain data for enabling the generator 32 to determine one or more conditions of the ultrasonic instrument 100 .
The ultrasonic instrument 100 may include an internal and/or external memory device 120 . The memory device 120 may include one or more predetermined interferential patterns 200 ( FIG. 6 ) based upon one or more conditions of the end effector assembly 90 and/or the waveguide assembly 60 (e.g., one or more of temperature, mechanical load, and positioning of the end effector assembly 90 relative to the shaft assembly 50 ) and/or may provide space to store data related to the one or more conditions (e.g., an actual interferential pattern 300 produced by the ultrasonic instrument as illustrated in FIG. 7 ). As such, this embodiment of the ultrasonic instrument 100 enables a user to measure various conditions of the ultrasonic instrument 100 .
In operation, one or more pulses “P” are generated with the transducer assembly 30 (e.g., by virtue of the one or more transducers 30 a ; see FIG. 1 ) as depicted in FIG. 5 . In embodiments, the generator 32 may be configured to generate and transmit the one or more pulses “P” or a series of pulses “P.” The transducer 30 assembly may generate a series of pulses “P” with the one or more transducers 30 a . The series of pulses “P” may have a frequency of at least about 200 cycles per nanosecond. The pulses “P” may be transmitted to the waveguide assembly 60 and the end effector assembly 90 , for example, with a frequency of 5 MHz, a duration of 3 microseconds, and repetition rate of 4 kHz. However, any suitable frequency, duration, and repetition rate may be utilized. As the pulses “P” propagate or scatter through the waveguide assembly 60 and the end effector assembly 90 , one or more waves “W”, which may be ultrasonic waves, are reflected by one or both of the waveguide assembly 60 and the end effector assembly 90 in response to transmission of the one or more pulses “P.” In this regard, the waveguide assembly 60 and/or the end effector assembly 90 may act collectively, or individually as a resonator to produce “echo” signals of the reflected waves “W.”
To this end, pulse duration “t” may be selected to be noticeably shorter than double the length “L” of the resonator (e.g., one or both of the waveguide assembly 60 and end effector assembly 90 ) over the sound velocity V: t=2L/V. In this regard, the pulse repletion rate should be close to the resonant frequency (e.g., V/2L) of the resonator. The changes in the conditions in the end effector assembly 90 result in changes of the resonator properties. In particular, the changes make the resonant frequency deviate from its initial value. Variations of the resonator properties also result in shape changes in the actual interference pattern. For example, where temperature is a condition, then increasing temperature results in a slight change of the distance between scattering points of the propagated waves, resulting in a phase change of the propagated waves. The phase change is manifested by shape changes in the actual interference pattern when comparing the actual interference patterns of the lower and higher temperatures.
The sensors 110 collect data representative of the reflection of the one or more waves “W” and transmit the data via one or more signals “S” to the generator 32 . In some embodiments, the generator 32 may also be used as a sensor to collect the data (e.g., by collecting the “echo” signal and converting the energy into an electrical signal). The generator 32 then registers (e.g., via microcontroller 34 ) the data transmitted via the one or more signals “S” and generates an interferential pattern of the one or more reflected waves “W.” Based upon the interferential pattern produced, the generator (e.g., via the microcontroller 34 ) identifies the one or more conditions of the end effector assembly 90 and/or the waveguide assembly 60 . The generator 32 may provide an output (e.g., via a display 36 operatively coupled to the ultrasonic instrument 100 ) of the one or more conditions. The output may be an audible, visual, or tactile signal of the one or more conditions. When the end effector assembly 90 is positioned in contact with tissue, the one or more conditions may correspond to the interaction of the end effector assembly 90 and tissue.
Further to the above, the one or more waves “W” may be registered for a predetermined time period (e.g., at least about 200 microseconds) that is greater than twice the predetermined length of the resonator (e.g., the waveguide assembly 60 and/or the end effector assembly 90 ), or portions thereof, divided by the sound velocity in the resonator.
Generated interferential patterns of the one or more registered reflected waves “W” may be compared (e.g., via the microcontroller 34 ) with the one or more predetermined interferential patterns stored on the memory device 120 . The pulses “P” may be adjusted in response to differences between one or more generated interferential patterns and one or more predetermined interferential patterns. Each condition of the end effector assembly 90 and/or waveguide assembly 60 may have one or more predetermined interferential patterns.
In one mode of operation, the operating temperature range of the ultrasonic instrument 100 may be calibrated from about room temperature to about three-hundred degrees centigrade.
In use, the operator of one of the presently disclosed ultrasonic instruments 10 , 100 receives information about conditions of the ultrasonic instrument, in real-time during operation thereof. For example, when the operator is aware of the temperature of the end effector assembly 90 , the operator can avoid thermal damage of tissue being manipulated by the ultrasonic instrument.
With this purpose in mind, the presently disclosed ultrasonic instruments 10 , 100 may include any suitable number of electrical connections, configurations, and/or components (e.g., resistors, capacitors, inductors, rheostats, etc.), mechanical connections, configurations, and/or components (e.g., gears, links, springs, members, etc.), and/or electro-mechanical connections, configurations, and/or components such that presently disclosed ultrasonic instrument 10 , 100 may function as intended.
While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto. | A method of measuring conditions of an ultrasonic instrument includes providing an ultrasonic instrument that includes an end effector and a waveguide operably coupled to a generator and the end effector. The method involves generating one or more pulses with the generator, transmitting the one or more pulses to one or both of the waveguide and the end effector, generating one or more waves that scatter in an interferential pattern in response to the transmission of the one or more pulses, registering a signal indicative of the interferential pattern, generating an actual interferential pattern based upon the signal, and identifying one or more conditions of the end effector based upon the actual interferential pattern. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to systems for controlling movements of a workpiece along a path, and particularly to such systems where backlash is substantially reduced for avoiding uncontrolled movements of the workpiece.
This application incorporates by reference the teachings of application Ser. No. 09/427,392 entitled “Apparatus and Method For Fabricating Optic Fiber Preforms”, filed Oct. 25, 1999, simultaneously with the filing of this application.
In numerous manufacturing processes, a carriage is moved back and forth along a path, an example being a lathe where a tool is moved back and forth along a path parallel to the axis of a rotating spindle. In some processes, it is essential that the rate of movement of the carriage be extremely precise and controlled. While it is generally possible to achieve highly controlled movements of the carriage in any direction, a problem generally exists at the ends of the carriage path where the carriage must stop and change direction. The problem arises from the fact that even in the most precisely machined apparatus, some degree of looseness of fit among parts of the system exists either directly from the manufacturing tolerances or from inevitable wear. Thus, when the carriage, moving in one direction, first stops and begins to move in the opposite direction, some inevitable lag, and accompanying uncontrolled movement of the carriage, occurs until parts in the drive train, pushing against one another in one direction, move through tiny gaps for re-engaging and pushing one another in the opposite direction.
Various means, such as constant friction members and spring loaded members are known for maintaining parts of a driving train in constantly stressed relationship for avoiding backlash. The present invention provides a novel arrangement which is quite simple and relatively inexpensive to implement.
SUMMARY OF THE INVENTION
First and second independent force generators (e.g., known a.c. or d.c. motors) provide controlled and variable amounts of force to a carriage to cause movement of the carriage in a first direction or in a second, opposite, direction (e.g., forward and reverse directions). At certain periods of time, the forces from first and second independent force generators are simultaneously applied to the carriage so as to oppose each other with the direction of movement of the carriage being determined by the larger of the two forces. The forces of the first and second force generators are always applied at the ends of travel of the carriage just prior to the carriage coming to a stop and reversing its direction of movement, e.g., from forward to reverse. Thus, at each end of travel, when one of the first and second force generators is exerting a force causing movement of the carriage in one direction, the variable force of the other one of the first and second force generators which, when large enough, causes reverse direction movement of the carriage, is already being applied against the carriage. Backlash is thus significantly reduced, if not avoided.
In one embodiment, both forces are applied continuously against the carriage, with the rate of movement being determined by the larger of the forces, and with the smaller force providing braking for greater precision of the driving of the carriage by the larger force.
DESCRIPTION OF THE DRAWING S
FIG. 1 is a view, in perspective, of a generally known lathe-type apparatus modified according to the present invention;
FIG. 2 is a side sectional view of a torque transmitting mechanism in accordance with one embodiment of the invention; the mechanism being disposed within a housing shown in FIG. 1;
FIG. 2A is a view similar to FIG. 2 but showing a modification thereof; and
FIG. 3 is a block diagram of a motion control circuitry in accordance with the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows a lathe-type apparatus making use of the present invention. An elongated glass tubing 10 is supported between two chucks 12 . Reactant gasses are passed through the tubing between the chucks for the deposition of soot particles on the tubing walls. A controlled conversion of the soot p articles into layers of glass is obtained in response to controlled heating of the tube by flames from a gas burner 14 travelling back and forth along the tube length. In certain processes, e.g., the formation of an optic fiber glass boule made in apparatus of the type herein shown, precision movement of the gas burner 14 back and forth along the tubing is essential. Although the burner 14 must change speed upon each reversal of direction, provided no backlash is present, the rates of speed change can be known and compensated for by other changes in the processing, e.g., by the rates of gas flow through the tubing. The present invention provides means for driving the burner 14 back and forth along the tubing 10 essentially without any backlash. Also, in a preferred embodiment, not only is backlash avoided, but improvement in the control of the rate of movement of the carriage along the entire length of its travel is obtained.
As shown in FIG. 1, the gas burner 14 is mounted on a carriage 20 mounted for being driven along a drive screw 22 by rotation of a nut (not visible in FIG. 1) along the drive screw 22 . Either the screw or the nut can be rotated and, in either case, the carriage is inelastically connected to the nut for axial movement therewith. Mechanisms, such as used in lathes, drill presses and the like, can be used for mechanically interconnecting the screw driven nut to the carriage 20 . In known apparatus, the drive screw is typically controllably rotated for linearly advancing a nut and attached carriage along the axis of the screw. Alternatively, a motor is coupled to the nut for rotating it for screwing it along the drive screw. In such case, a bearing is typically used for securing the carriage to the nut for free rotation of the nut relative to the carriage while linearly moving the carriage in exact correspondence with movement of the nut along the screw.
The present invention is relevant to how the nut (or nuts) used for moving the carriage is itself moved. In the embodiment illustrated in FIG. 1, a stationary drive screw 22 is used rigidly secured between two stationary blocks 24 . A housing 28 is mounted for axial movement along the screw 22 by drive means, to be described, in threaded engagement with the screw. The housing 28 is rigidly secured to the carriage 20 on which the gas burner 14 is rigidly mounted. FIG. 1 shows one side of the carriage. The other side (not visible in FIG. 1) is slidably mounted on a shaft precisely parallel to the drive screw 22 . Mounted on the housing 28 for movement therewith are two motors 32 and 34 used for driving the carriage 20 . Each motor is independently operable by a known control means, not shown, and each motor provides two functions. One function is to continuously move the housing 28 and the carriage 20 in a respective direction axially along the drive screw 22 . The other function of each motor is to serve as a brake for slightly resisting the movement of the housing 28 caused by the other motor.
Each motor 32 and 34 has, respectively, a drive shaft (not visible in FIG. 1) for turning a pulley 32 a and 34 a and a belt 32 b and 34 b . The two belts 32 b and 34 b drive respective pulleys 32 c and 34 c for transmitting torque developed by the respective motors 32 and 34 to carriage driving means disposed within the housing 28 .
FIG. 2 shows one embodiment of a carriage driving means which can be disposed within the housing 28 shown in FIG. 1 . The driving means comprises two ball nuts 38 and 40 of known type each comprising, in accordance with known technology, an inner, internally threaded cylinder 42 and an outer cylinder 44 freely rotatable relative to the inner cylinder 42 by ball bearings 46 , but rigidly connected to the inner cylinder for axial movement therewith.
The ball nuts 38 and 40 are identical, each is meshed with the drive screw 22 and each is driven by a respective motor 32 or 34 . Thus, as illustrated in FIG. 2, the pulley 32 c driven by the belt 32 b from (FIG. 1) the motor 32 is rigidly secured to the inner cylinder 42 of the ball nut 38 for applying torque against the inner cylinder 42 in response to torque generated by the motor 32 . Similarly, torque generated by the motor 34 is applied to the inner cylinder 42 of the ball nut 40 by means of the belt pulley 34 c rigidly secured to the inner cylinder 42 of the ball nut 40 .
The use of single ball nuts of the type shown in FIG. 2 for driving lathe-type apparatus is known and, using but one ball nut 38 or 40 , the apparatus shown in FIG. 2 could be used for driving a known prior art lathe-type carriage. Considering only the ball nut 38 , for example, and assuming the absence of the ball nut 40 , the outer cylinder 44 of the ball nut 38 is rigidly coupled to the carriage 20 (see, also, FIG. 1) and, upon operation of the motor 32 for causing rotation of the inner cylinder 42 of the ball nut 38 , the ball nut 38 is axially screwed along the drive screw 22 for axially advancing the carriage 20 . The motor 32 is reversible, and travel of the carriage 20 in both directions is obtained under control of the single motor 32 .
In the embodiment of the invention illustrated in FIG. 2, both nuts 38 and 40 are present, both are respectively rigidly connected to the two pulleys 32 c and 34 c which, in this embodiment, are rigidly engaged (FIG. 1) to the drive shafts of the respective motors 32 and 34 . As previously noted, both motors are, at times, simultaneously powered for developing torques tending to rotate the two ball nuts 38 and 40 in opposite directions. No belt slippage occurs, and all the rotatable parts, i.e., the respective pairs of pulleys 32 a , 32 c and 34 a , 34 c , and the two belts 32 b and 34 b , are all rotatable in directions corresponding to axial movements of the two ball nuts 38 and 40 in the same direction. What occurs is if, for example, the motor 32 is energized to generate a higher torque than that generated by the motor 34 , all directions of movement in the drive train are determined solely by the direction of turning of the motor 32 . Thus, if the motor 34 (of lower torque) would, if energized in the absence of the motor 32 , turn in a direction to rotate its drive shaft clockwise and to attempt to rotate the ball nut 40 , e.g., clockwise for advancing the carriage to the left, owing to the higher torque of the motor 32 , the torque applied by the motor 34 is overcome and the greater or net torque applied to the ball nut 38 causes actual rotation of the nut 38 (in this example) counter clockwise and actual advance of the carriage 20 to the right. Because the ball nut 40 is rigidly threaded on the drive shaft 22 , actual movement of the carriage 20 to the right causes actual counter clockwise rotation of the ball nut 40 . Thus, while the torque generated internally of the motor 34 coupled to the ball nut 40 is in a direction to cause clockwise rotation of the drive shaft of the motor 34 , the counterclockwise rotation of the ball nut 40 (as caused by the rightward movement of the carriage 20 along the drive shaft 22 ) causes counterclockwise rotation of the drive shaft of the motor 34 . The motor 34 is thus driven backwards in a direction opposite to the direction of torque being generated by the motor 34 . The “counter direction” torque produced by the motor 34 acts as a drag against the “forward direction” torque of the motor 32 driving the ball nut 38 to the right.
A principle use of the “counter torque” (i.e., that torque being produced by the motor not actually driving the carriage 20 ) is to eliminate backlash in the drive train at the time of reversal of direction of the carriage. In the absence of a two motor drive system, as herein disclosed, a typical practice is, as previously noted, to rotate a carriage mounting ball nut by a single, reversible motor. As known, in the absence of special means for preventing backlash, some degree of looseness in the drive train of such single motor systems is inevitably present leading to backlash at the time the carriage first comes to a stop and begins travel in the reverse direction. For example, during movement of a single motor driven carriage to the right along a drive screw, all engaging parts of the drive train are firmly pressed against one another and are at least slightly strained (distorted) in directions corresponding to the direction of force transmittal along the drive train. When the carriage comes to a stop and the single motor drive shaft begins to turn in the reverse direction, actual movement of the carriage does not begin until all the strains in the right-hand, force transmitting direction are reversed, and any gaps between surfaces providing force transmittal in the left-hand direction are closed. This takes time and, more significantly, is a function of the tolerances actually present when the drive train is first assembled and how these tolerances change with time and wear of parts. Such factors are not known and, even if measured at any time, change with time. Thus, during the period when backlash is delaying positive transmittal of movement causing forces, the movement of the carriage is not under direct control and is randomly variable. Such unknown and uncontrolled movements of the single motor driven carriage, at the instants of reversal of direction of the carriage, can lead to undesirable variations in the processing of a workpiece or a workpiece processing tool mounted on the carriage.
In accordance with the present invention, however, by energizing one of the two motors not actually advancing the carriage just shortly before the carriage reaches the end of its travel in a “forward” direction, a “reverse” direction force is created which causes the force transmitting parts of the drive train associated with the reverse direction driving motor to be in rigid force transmitting relationships. Thus, at the instant when the carriage stops travel in the first direction and is to start travel in the reverse direction, no time delay occurs for the transmittal of the reverse direction force which is already being transmitted prior to the stoppage of the carriage.
Another problem associated with changing direction of travel of a carriage is that the carriage must come to a complete halt, even if only for a vanishingly small instant. Standing friction is considerably higher than moving friction, and restarting of the carriage cannot occur until the reverse driving force is large enough to overcome such standing friction. Thus, with a single motor, at the instant the motor shaft begins to turn in an opposite direction, for reversing the direction of movement of the carriage, even after backlash has been overcome and reverse direction force is being transmitted through the drive train, no carriage movement begins until the level of force being transmitted increases to an amount sufficient to overcome standing friction.
In accordance with the present invention, however, by applying a reverse direction force to the carriage in a “threshold” amount greater than the force to overcome standing friction, upon removal of the forward direction driving force, a reverse direction driving force sufficiently large to overcome standing friction is already present for immediate application against the carriage.
Stating the foregoing slightly differently, the axial directions of movements of the ball nuts 38 and 40 are determined by the sum or net of the two oppositely directed forces being applied. At the end of travel of the carriage in the “forward” direction, the torque from the forward direction driving motor is reduced while the torque from the drag producing motor is increased. Because no backlash is present (as previously described), the rates of torque change are a function solely of the speed control parameters of the motors. When the opposing torques are equal, the net torque on the two ball nuts 38 and 40 is zero and the carriage has come to a complete halt. Although the net torque on the two ball nuts is zero, the actual level of torque being applied by the reverse driving motor is, as described, above the level necessary to overcome standing friction and, dependent solely upon the rate of decrease of torque from the forward driving motor, a large reverse direction driving torque is essentially immediately available for reverse driving the carriage.
As above-described, stoppage and re-starting of travel of the carriage is a function of the rates of change of torque from two motors. Using a single motor, stopping and re-starting the carriage involves bringing the motor torque completely to zero and then raising the torque level, in the opposite direction, sufficiently high to overcome standing friction. With two motors, stoppage and re-starting can occur while the torque from the forward direction driving motor is still relatively high, as determined by the magnitude of torque from the reverse driving motor, and essentially independent of the subsequent further reduction in torque of the forward direction motor.
For example, if the torques for driving the carriage in either direction are 10 ft-lbs, cross-over of torques (for zero net torque) can occur at a high level, e.g., at 9 ft-lbs from each motor, or at a low level, e.g., at 3 ft-lbs (but always, as described, at a level above that necessary for overcoming standing friction). Provided the motor providing the drag function is turned on only shortly before the carriage reaches its turn-around point, it is generally preferable that a high cross-over torque level is used. Then, only a minimum time delay is present before the reverse direction torque reaches the illustrative steady-state level of 10 ft-lbs.
Turning on the reverse direction torque applying motor only shortly before the carriage reaches the end of its forward direction travel is most economical in the use of electrical power.
However, in a preferred embodiment, both motors are on constantly, throughout the forward and backward travel of the carriage, but with one motor drive train providing a higher torque than the other motor drive train for driving the carriage in a “forward” (or “backward”) direction, and the other motor drive train applying a relatively small torque opposing the forward (or backward) direction driving torque. The presence of the small (and constantly applied) opposing torque tends to provide a more uniform rate of travel of the carriage. The speed of travel of the carriage is a function of the net of the driving torques and the system friction. In the prior art, using but one, reversible driving motor, the speed of travel is a function only of the motor driving torque and the system friction. While the motor driving torque is quite accurately controllable, the friction of the system tends to be variable, particularly with time and with variable wear. Thus, during driving of the carriage with but a single motor, the sudden encountering of a change in friction in the system can result in a lurching of the carriage. Such lurching is significantly decreased using two opposed driving torques because the opposing torque serves as a brake against sudden lurchings in response to decreases of friction in the system.
In another embodiment, shown in FIG. 2A, the two separate ball nuts 38 and 40 shown in FIG. 2 are combined as a single ball nut 38 - 40 identical to either ball nut 38 or 40 but with both motor drive n belt pulleys attached at opposite ends of a common inner cylinder 43 . Operation is the same as previously described. With both motors 32 and 34 energized, the motor providing the higher torque determines the direction of movement of the carriage while the other motor provides a braking force.
As described, each motor 32 and 34 provides two functions; one being to drive the carriage along the drive (lead) screw and the other being to oppose the motion of the carriage. It is possible, however, to separate the two functions. For example, in the embodiment shown in FIG. 1, the drive screw 22 is stationary and power for advancing the carriage is provided through the two motors. Alternatively, the drive screw 22 can be rotated by a motor, not shown, but which can be disposed, for example, within one of the stationary blocks 24 , whereby it is the rotation of the drive screw which provides power for advancing the carriage or the two nuts 38 and 40 . In such rotating screw arrangement, while the two motors are not used for causing movement of the carriage along the drive screw, the two motors are used, as previously described, for opposing axial movements of the carriage and for reducing backlash between the drive screw and the carriage.
A situation where it might be preferable to rotate the drive (lead) screw is with an exceptionally massive carriage requiring quite large motor power for carriage movement. Thus, two quite large motors 32 and 34 would be required in the embodiment shown in FIG. 1 . If the motors 32 and 34 served solely the backlash reducing function, smaller motors (movable with the carriage) could be used. However, means would still have to be provided for reducing backlash between the drive screw rotating motor and the drive screw. With the stationary drive screw arrangement shown in FIG. 1, all backlash in the power drive trains between the carriage moving power sources (e.g., the motors 32 and 34 ) and the carriage is essentially removed.
Although the invention has been described in connection with linear motion of a carriage, controlled rotary motion can also be utilized. For example, if the two ball nuts 38 and 40 shown in FIG. 2 are replaced with two separate and spaced apart hubs of a single rotatable wheel fixedly secured to a common shaft rotatable under control of the two motors 32 and 34 , the two motors would function to provide controlled, reversible direction of the wheel without backlash and with minimal uncontrolled lurchings in response to instantaneous variable loading of the wheel. (A more simple arrangement is a single hub driven by two motor driven belt pulleys secured at axially opposite ends of the single hub.)
In general, known types of force generators can be used in the implementation of the invention. A.C. induction motors, d.c motors or even stepper motors under control of known power controlling systems can be used; similarly, hydraulic, pneumatic motors and the like can be used.
By way of example of a suitable control system, FIG. 3 is a block diagram showing electrical controls for the motors 32 and 34 . The motor control circuit 701 supplies electrical power to the motors. In the illustrative process shown, for making an optical fiber preform, the motor control circuit is controlled by a micro-controller or programmer 703 preprogrammed with information as to the distance the carriage 20 (FIG. 1) must travel along the tube, permissible rates of increase of the speed and/or torque of the motors and the desired speed at which the carriage is to go in the steady state condition along most of the length of the tube 10 . Alternatively, the system may include optical and/or electronic sensors 705 to sense when the carriage nears or reaches the ends of the travel path. These sensors 705 then provide signals to the programmer 703 to initiate the application of power to the motors such that the carriage decelerates, then stops, and then accelerates in the opposite direction.
The system embodying the invention may also include a torque sensor circuit 707 to sense the differential torque produced by the motors 32 and 34 . To prevent backlash and/or dither and/or jerky motion, it is desirable that the torques of the motors do not change too quickly relative to one another. To achieve this result, a differential torque sensor 707 is used and its output is fed back to the programmer 703 to supply correct control signals to the motor control circuit 701 which supplies the electrical power to the motors.
In systems for making fiber optic preforms embodying the invention, there is much greater control over the formation of the glass layers within the tube 10 . For example, during the time when the carriage changes direction and travels at a lower average speed, a greater degree of heat is applied to the tube. However, owing to the high degree of control in the movements of the carriage provided by the invention, the profile of the reactants and gas vapors can be modified to compensate for the rate change of movement of the carriage. Furthermore, since the movement of the carriage assembly is tightly controlled by the motors, a high degree of compensation is possible. Thus, in FIG. 3, the programmer 703 produces an output signal on line 708 which is supplied to a reactant and gas vapor control 709 which controls the amount of reactants and gas vapors applied to the tube based upon the known rates of movement of the carriage at the ends of the path of carriage travel. Thus, uniform processing is obtained in spite of the inevitable, but known, carriage speed changes.
While the invention has been described in detail herein in accord with certain embodiments thereof, many modifications and changes therein may be effected by those skilled in the art. Accordingly, it is intended by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention. | Apparatus embodying the invention includes first and second motors coupled to a carriage assembly for moving the carriage assembly back and forth between first and second end points. The first motor is for developing a force to drive the carriage in one direction and the second motor is for developing a force to drive the carriage in an opposite, second direction. When the first motor causes the movement of the carriage in one direction, the slowing, stopping and reversal of the carriage is achieved by varying the power supplied to the second motor relative to the power supplied to the first motor until the force exerted by the second motor first equals and then exceeds the force exerted by the second motor. So operated, the carriage motion is well controlled and exhibits little, if any, backlash. | 5 |
RELATED APPLICATIONS
[0001] This application claims benefit to and is a continuation-in-part of U.S. patent application Ser. No. 14/292,803, filed May 30, 2014 entitled “Paddle Clip”, which is herein incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The disclosed apparatus relates to a clip to secure a paddle to a belt of a person.
BACKGROUND
[0003] A paddle for use while standing on a kayak, canoe or standup paddleboard is comprised of an elongated shaft having a first end and a second end, at least one end of the shaft having a blade attached thereto and the other end having a handle, grip, or another blade.
[0004] There is currently no clip designed to hold a paddle on a belt. Rather, current paddle clips are typically designed to attach to a watercraft. In many cases, the manner in which the paddle is attached requires a user to either kneel, sit or awkwardly bend down to either secure or retrieve the paddle. For example, some paddle clips are mounted to the gunwale or cockpit rim of a watercraft. Such retaining devices do not provide a means for a user to free himself of his paddle while remaining standing and then later regain access when necessary without bending or kneeling. Furthermore, current clips do not provide a means for a user to stow the paddle in several positions. Current clips also do not provide a user with a convenient and safe means for quick one hand storage and retrieval of the paddle.
[0005] There are many belt accessories and specialty belts with pouches and holders for holding sporting gear, camera gear and fishing gear. For example, there are many fishing pole holders on the market that allow fishermen to secure their rods in a belt rod holster. The various pole holders are used to free up the users hands of the fishing gear. However, none of these address the current problem of how to secure a paddle to free up the hands to allow the user to fish. While a fishing pole holder takes care the problem of freeing both hands for paddling, the fishing pole holder does not provide a reasonable mechanism for freeing a fisherman's hands of a paddle to allow the fisherman to fish.
[0006] Another example of a situation in which a standup paddleboard user (i.e., a paddleboarder) requires free hands is when the paddleboarder wishes to take photographs. A photographer needs to adjust camera settings, change lenses, clean the lens, and ultimately take pictures. Each of these activities requires the use of both hands free from the paddle. The same holds true for using binoculars for bird watching. While a user can place the binoculars around his neck, it is advantageous for user to use both hands on the binoculars, free from the paddle. These are but a few of many examples of difficulties faced by users of paddleboards in trying to deal with their paddle.
[0007] Accordingly, there is a need for a mechanism to allow a paddle to be stored quickly so that opportunities to do other activities are not missed. Examples are, casting a fishing pole quickly when fish appear in the water, taking a photo of a wildlife subject before the subject moves, or taking aim while hunting with bow and arrow.
[0008] In addition, it would be advantageous in light of safety concerns to provide a means by which the paddle can be retrieved quickly and easily to avoid collision with objects in the water. Such objects include branches, rocks, water plants, and trees. In addition, it is desirable to have quick access of the paddle to avoid colliding with objects on shore, such as trees, plants, boulders, rocks and steep embankments and the shore itself. Furthermore, by having quick access to the paddle, the user can avoid shallow water where the watercraft could become stuck. All these conditions and others are potentially harmful to the paddler and require the ability to retrieve the paddle quickly for safety.
[0009] Also, it is desirable to be able to retrieve the paddle easily so that the paddler does not fall into the water while bending, stooping, or over reaching for the paddle while standing on an unstable watercraft. It is also desirable for a user to be able to retrieve a paddle quickly to maneuver the watercraft into the best position and location for fishing, viewing, hunting or photographing the surroundings.
[0010] Therefore, there is a need for a means by which a paddler on a watercraft can easily stow and retrieve the paddle.
SUMMARY
[0011] The disclosed apparatus is a paddle clip. In accordance with one embodiment, the paddle clip can be attached to a belt. One embodiment of the clip secures a paddle used by a standup paddler while the paddler is in the standing position, thus freeing up the paddler's hands. The paddle can be secured into, or retrieved from, the clip using one hand. In addition, the paddler can move the paddle into multiple positions as necessary to make it easier and more comfortable for the paddler to use both hands and to move freely without interference from, or the encumbrance of, the paddle. The disclosed apparatus provides quick and easy access to the paddle.
[0012] In accordance with one embodiment of the disclosed apparatus, the clip comprises a piece of sheet plastic (such as PVC, ABS or other such material), or a laminate or sheet metal, spring steel or other such material with a substantially elongated shape having a back plate and a flexible resilient clip portion with an opening configured for accommodating a cylindrical shaft of a paddle parallel with the longitudinal axis of a trough in the clip. The clip has an opening to facilitate squeezing the shaft of a paddle into the clip with one hand. In addition, using only one hand, the fingers can lift open the clip. The body of the clip has a second opening large enough for thumb or finger to press downward while lifting open the clip to release paddle shaft onto the fingers of the same hand. The body of the clip also has a back plate that urges the paddle shaft to rest in the trough of the clip.
[0013] In accordance with one embodiment, the clip is fabricated out of a plastic that ensures that the clip is sufficiently flexible to open while being stiff enough to secure the paddle and close the clip once the paddle is in the trough. The use of molded or sheet plastic allows for inexpensive production. However, in an alternative embodiment, the clip could be manufactured out of sheet metal, wire, synthetic materials or laminates.
[0014] Accordingly, it is one object to provide a convenient method for a standup paddler to secure his paddle while standing for safety thus eliminating the need to stoop, kneel, bend or end up in an awkward position to set the paddle down or clip a paddle into a holder on a watercraft.
[0015] Another objective is to provide the ability to secure and retrieve the paddle with one hand for convenience and safety.
[0016] Another objective is to provide the ability of the paddler to rest either end of the paddle on the deck of the watercraft or in the water, or balance the paddle completely in the paddle clip.
[0017] Another objective is to allow a paddle to be slid in any number of positions along the trough of the paddle clip for convenience and safety. This allows for body movement such as sitting and for moving the paddle out of the way of objects, and for convenient use the use of the hands.
[0018] Another objective is to allow the clip to be used anywhere on a belt, at the front, side or back to accommodate whatever is the most comfortable position for the paddler.
[0019] Another objective is to provide an extremely secure attachment of the paddle at the same time having it easily accessible and positionable. When performing other task such as fishing, photograph or hunting while stand up paddling, winds, rough weather conditions, rough seas, bumping the paddle with hands or other objects could knock the paddle out of the clip if it were not extremely secure, thus if it were not extremely secure a very dangerous situations could occur where the paddle ends up in the water leaving the paddler without his main means of guidance and propulsion.
[0020] Another objective is to provide a paddle clip that can be used on belts manufactured for various sports including fishing, photography, hunting and bird watching without exclusivity to any one sport or for use by itself on a general purpose belt.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The disclosed method and apparatus, in accordance with one or more various embodiments, is described with reference to the following figures. The drawings are provided for purposes of illustration only and merely depict examples of some embodiments of the disclosed method and apparatus. These drawings are provided to facilitate the reader's understanding of the disclosed method and apparatus. They should not be considered to limit the breadth, scope, or applicability of the claimed invention. It should be noted that for clarity and ease of illustration these drawings are not necessarily made to scale.
[0022] FIG. 1 is a front perspective view of a clip 100 in accordance with one embodiment of the disclosed apparatus.
[0023] FIG. 2 is a front perspective view of the clip with the rounded top section being distorted (i.e., the radius of the curvature expanded) to open the clip and thus allow a paddle or other such device to enter the trough through the expanded opening 6 .
[0024] FIG. 3 is a side view of the clip with a cross section of a paddle shown in the trough of the clip.
[0025] FIG. 4 illustrates the clip opening to allow the shaft of a paddle to enter the clip.
[0026] FIG. 5 is a rear perspective view of the clip.
[0027] FIG. 6 is an illustration of a paddle clip holding a paddle and mounted on a belt.
[0028] FIG. 7 is an illustration of a paddle clip with a flap for securing the clip to a paddler.
[0029] The figures are not intended to be exhaustive or to limit the claimed invention to the precise form disclosed. It should be understood that the disclosed method and apparatus can be practiced with modification and alteration, and that the invention should be limited only by the claims and the equivalents thereof.
DETAILED DESCRIPTION
[0030] FIG. 1 is a front perspective view of a clip 100 in accordance with one embodiment of the disclosed apparatus. The clip 100 is made from a single sheet of resilient plastic material having a thickness of between 1/16 inch to ¼ inches. However, in an alternative embodiment, the clip 100 can be made of a metal, synthetic materials or any other resilient material that will allow the clip 100 to be slightly deformed and return to the original shape.
[0031] The clip 100 has a flat back plate 1 , a rounded top section 14 that extends from the flat back section, an essentially flat front section 13 that extends from the rounded top section and a rounded bottom section 5 that extends from the flat front section to create a trough 4 . The rounded bottom section 5 curls around leaving an opening 6 between the distal end 9 of the rounded bottom section 5 and the back plate 1 . The thickness and elastic properties of the plastic used to form the clip 100 allow the clip 100 to be deformed and then to spring back to its original shape and thus close after being pulled open. The clip 100 is pulled open by pulling the front section 13 laterally away from the back plate 1 . The material used to form the clip 100 has sufficient integrity to allow the clip 100 to open to allow a paddle shaft to enter the clip and then close once the paddle shaft is within the trough 4 . Furthermore, the resilient material has sufficient integrity to retain a paddle within the trough 4 once the clip closes, as will be described in greater detail below.
[0032] FIG. 2 is a front perspective view of the clip 100 with the rounded top section 14 being distorted (i.e., the radius of the curvature expanded) to open the clip 100 and thus allow a paddle or other such device to enter the trough 4 through the expanded opening 6 (See FIG. 4 ).
[0033] FIG. 3 is a side view of the clip 100 with a cross section of a paddle shown in the trough 4 of the clip 100 . FIG. 4 illustrates the clip 100 opening to allow the shaft of a paddle 7 to enter the clip 100 . A space 8 between the front section 13 and the back plate 1 expands when the front section 13 pulls away from the back plate 1 to open the clip 100 and thus allow the shaft of the paddle 7 to enter past the rounded bottom 5 . The diameter of the curve in bottom section 5 and the trough 4 and the diameter of the curve of the rounded top section 14 of the clip 100 are roughly equal to the diameter of a shaft 7 of a paddle that the clip 100 will accommodate. The bottom section 5 of the clip forms the trough 4 in which the paddle 7 is captured. When the clip is not holding a paddle 7 , the front section 13 of the paddle clip 100 and the back plate 1 are essentially parallel. The back plate 1 extends approximately 1½ inches beyond the rounded bottom 5 of the clip 100 .
[0034] Typically, the clip 100 is opened by sliding the shaft of a paddle 7 (or other such object to be held by the clip 100 ) along the back plate 1 . As the paddle 7 comes into contact with the rounded bottom section 5 , the curvature of the rounded bottom section 5 will engage the paddle 7 and slide outward to allow the paddle 7 to pass through the opening 6 and into the trough 4 . Alternatively, the user can gently pull from below on the rounded bottom section 5 to pull the rounded bottom section 5 away from the back plate 1 to expand the opening 6 and thus assist the paddle 7 in entering opening 6 .
[0035] FIG. 5 is a rear perspective view of the clip 100 . The space 8 within the clip 100 has a vertical height 16 of between 1 and 2½ times the diameter of the shaft 7 of the paddle to be held by the clip 100 . A thumb opening 3 (see FIG. 1 ) in the front section 13 of the paddle clip 100 is sized to accommodate a person's thumb (i.e., approximately 1¼ inch wide). The thumb opening 3 is configured to allow the user to press down with the user's thumb (not shown) on the shaft 7 of a paddle when a paddle is captured in the clip 100 . Pressing down on the shaft 7 of the paddle applies a sufficient pressure to the rounded bottom 5 to both cause the rounded bottom 5 to slightly distort (i.e., straighten out) and/or to push the front section 13 away from the back plate 1 , expanding the space 8 (as shown in FIG. 4 ) and thus allow the shaft 7 of the paddle to slip between the distal end 9 of the rounded bottom 5 and the back plate 1 . The vertical length of the thumb opening 3 extends along the front section 13 roughly from the lower portion of the rounded top section 14 to the bottom of the trough 4 .
[0036] The material from which the clip 100 is fashioned will be sufficiently sturdy to hold a paddle shaft 7 in place once disposed within the trough 4 . In accordance with one embodiment of the disclosed apparatus, the curved portion of the trough 4 forms an arc of approximately 180 degrees. Accordingly, the trough 4 will cradle and hold a paddle shaft 7 in place.
[0037] The overall width of the clip is between 2 to 5 inches and overall height is between 1½ inches and 6 inches. The overall height of the front portion 13 of the clip is between 1¼ and 3 inches.
[0038] FIG. 6 is an illustration of a paddle clip holding a paddle and mounted on a belt. In accordance with one embodiment of the disclosed apparatus, as can be seen from FIG. 1 , FIG. 2 and FIG. 5 , the clip 100 has two slots 2 . The slots 2 provide a means by which the clip 100 can be mounted on a user's belt 11 . The end of the belt 11 is threaded through the first slot 2 from the inside to the outside and through the second slot 2 from the outside to the inside, thus securing the clip 100 to the belt. A paddle 10 is secured in the clip 100 . The Shaft 7 of the paddle is captured in the trough 4 (see FIG. 3 ). Alternatively, the clip can be permanently fixed to a belt by rivets, sewing, glue or other such well known means of attachment.
[0039] In accordance with one embodiment of the disclosed apparatus, the clip 100 is covered with a wrapping, such as a cloth material, webbed material. In one such embodiment, the covering is decorated to enhance the appearance of the clip 100 .
[0040] FIG. 7 is an illustration of a paddle clip with a flap for securing the clip to a paddler.
[0041] In the alternative embodiment of FIG. 7 , a paddle clip 101 has a flap 701 that protrudes from the back plate 1 . A paddler's belt or swimsuit can be captured between the flap 701 and the back plate 1 to secure the paddle clip 101 to the paddler's belt or swimsuit. Other such means for securing the paddle clip 101 to a piece of the paddler's apparel (e.g., the paddler's belt swimsuit, etc.) or to can be used as well and would be within the scope of the presently disclosed apparatus. For example, the flap 701 can be hinged to the back plate 1 . In one such embodiment, spring tension is capture the paddler's belt or swimsuit between the flap 701 and the back plate 1 .
[0042] Although the disclosed method and apparatus is described above in terms of various examples of embodiments and implementations, it should be understood that the particular features, aspects and functionality described in one or more of the individual embodiments are not limited in their applicability to the particular embodiment with which they are described. Thus, the breadth and scope of the claimed invention should not be limited by any of the examples provided in describing the above disclosed embodiments.
[0043] Terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing: the term “including” should be read as meaning “including, without limitation” or the like; the term “example” is used to provide examples of instances of the item in discussion, not an exhaustive or limiting list thereof; the terms “a” or “an” should be read as meaning “at least one,” “one or more” or the like; and adjectives such as “conventional,” “traditional,” “normal,” “standard,” “known” and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass conventional, traditional, normal, or standard technologies that may be available or known now or at any time in the future. Likewise, where this document refers to technologies that would be apparent or known to one of ordinary skill in the art, such technologies encompass those apparent or known to the skilled artisan now or at any time in the future.
[0044] A group of items linked with the conjunction “and” should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as “and/or” unless expressly stated otherwise. Similarly, a group of items linked with the conjunction “or” should not be read as requiring mutual exclusivity among that group, but rather should also be read as “and/or” unless expressly stated otherwise. Furthermore, although items, elements or components of the disclosed method and apparatus may be described or claimed in the singular, the plural is contemplated to be within the scope thereof unless limitation to the singular is explicitly stated.
[0045] The presence of broadening words and phrases such as “one or more,” “at least,” “but not limited to” or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent.
[0046] Additionally, the various embodiments set forth herein are described with the aid of illustrations. As will become apparent to one of ordinary skill in the art after reading this document, the illustrated embodiments and their various alternatives can be implemented without confinement to the illustrated examples. | A paddle clip for securing a paddle to a user and thus allowing the user to free his hands for other tasks. The paddle clip has an elongated back plate and a flexible resilient rounded bottom section with a trough configured to accommodate a cylindrical shaft of a paddle. The shaft of the paddle can be squeezed into the clip with one hand. In addition, using only one hand, the fingers can lift open the clip to release the paddle. A flat front section of the clip has a thumb opening large enough for a thumb or a finger to pass through to press downward and thus release paddle shaft onto the other fingers of the same hand. | 0 |
PRIOR RELATED APPLICATIONS
[0001] This application is a non-provisional application which claims benefit under 35 USC §119(e) to U.S. Provisional Application Ser. No. 62/190,413 filed Jul. 9, 2015, entitled “ROCK STRENGTH AND IN-SITU STRESSES FROM DRILLING RESPONSE,” which is incorporated herein in its entirety.
FIELD OF THE INVENTION
[0002] This invention generally relates to reservoir engineering. More specifically, the present invention relates to estimation of in-situ stresses of Earth's crust using drilling response.
BACKGROUND OF THE INVENTION
[0003] In-situ stress of the earth's crust is regarded as one of the most important parameters used in engineering design of oil and gas operations. For example, wellbore failure can occur when the stress concentrated around a borehole exceeds strength of the rock. Certain operational activities (e.g., depletion or injection) can alter initial in-situ stress state of a reservoir. These stress changes can cause slip on pre-existing faults, which can be helpful to enhance effective permeability and higher fluid production from the reservoir. However, enhanced permeability along a large fault may cause uncontrolled fluid escape outside the reservoir. Thus, efficient recovery of hydrocarbons can hinge on an accurate understanding of mechanisms of stress in the earth's crust and their dynamics with reference to oil field operation.
[0004] Conventional estimation of in-situ stress typically involves analyzing openhole logs and image data, which are collected at data rich interval at reservoir depth. These approaches often use analytical solutions for in-situ stress estimation based on elastic assumptions. These solutions generally require two parameters (i.e., Young's modulus and Poisson's ratio) to define elastic properties of the rock. The parameters can be determined by sonic and density logs or lab measurements. However, these stress estimation approaches cannot be used or struggle in cases where sonic and image data is lacking. Data scarcity can be very common in overburden section of a well, in development wells due to production constraints, and in unconventional wells due to budgetary constraints.
BRIEF SUMMARY OF THE DISCLOSURE
[0005] This invention generally relates to reservoir engineering. More specifically, the present invention relates to estimation of in-situ stresses of Earth's crust using drilling response.
[0006] One example of a method for estimating in-situ stress of an interval having drilling response data includes: obtaining drilling response data of a data rich interval with available data; estimating relative rock strength as a composite value that includes in-situ stress and rock strength; estimating a Poisson's ratio from the relative rock strength; generating a stress model that includes uniaxial strain model using the Poisson's ratio; verifying the stress model with the available data; and applying the stress models in a non-data rich interval.
[0007] Another example of a method for estimating in-situ stress of an interval having drilling response data includes: obtaining drilling response data of a data rich interval with available data; b) estimating relative rock strength as a composite value that includes in-situ stress and rock strength; c) estimating a Poisson's ratio from the relative rock strength; generating a stress model that includes horizontal maximum and minimum stress models that use the Poisson's ratio; verifying the stress model with the available data; and applying the stress models in a non-data rich interval.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] A more complete understanding of the present invention and benefits thereof may be acquired by referring to the follow description taken in conjunction with the accompanying drawings in which:
[0009] FIG. 1 illustrates basic elements of drilling
[0010] FIG. 2 illustrates steps involved in estimating in-situ stress.
DETAILED DESCRIPTION
[0011] Turning now to the detailed description of the preferred arrangement or arrangements of the present invention, it should be understood that the inventive features and concepts may be manifested in other arrangements and that the scope of the invention is not limited to the embodiments described or illustrated. The scope of the invention is intended only to be limited by the scope of the claims that follow.
[0012] The following examples of certain embodiments of the invention are given. Each example is provided by way of explanation of the invention, one of many embodiments of the invention, and the following examples should not be read to limit, or define, the scope of the invention.
[0013] In-situ stress is typically estimated using analytical tools based on frictional equilibrium concept or elastic plane-strain concept. These tools require image and sonic logs and core lab tests to estimate the stresses. Usually, these data are only available at reservoir depth as sonic and image log response are not recorded in an overburden interval.
[0014] The present invention provides tools and methods for estimating principal in-situ stresses of the earth's crust using drilling response data, which is readily available in most if not all drilled wells. Analytical and empirical tools can be utilized to estimate stresses using obtained drilling response such as weight on bit (WOB), rate of penetration (RoP), and rotations per minute (RPM), mud type and the like. Data rich reservoir intervals are used to calibrate and validate drilling response related stress model, which in turn can be used at intervals and wells that lack sonic and image data. Using this approach, stresses can be estimated in overburden intervals, and development and unconventional wells where sonic and wellbore image logs may not be collected due to field limitations or budgetary constraints. Thus, one of the advantages of the present invention is that in-situ stress can be estimated independently along a wellbore in intervals where drilling responses may be the only available data. Other advantages will be apparent from the disclosure herein.
[0015] An accurate estimation of in-situ stresses is highly useful in many important applications. For example, the present invention may be used to address containment issues where reservoir and injected fluid leaked through faults, natural fracture or hydraulic fractures. This leakage can occur because of a lack of constraint on the in-situ stress, which prevents estimating a threshold injection pressure in the reservoir or disposal intervals. In one embodiment, the present invention can provide estimation of in-situ stress throughout the wells to obtain an uncertainty range in injection pressure.
[0016] In some development wells, data are not collected because it is assumed that the data collected from exploration wells are sufficient to estimate stress at reservoir depth. This is not always true. Even years of production and injection change the in-situ stress and data from a nearby well does not ensure a correct estimate of in-situ stress. In one embodiment, the present invention obtains current in-situ stress by calibrating stress model at data rich exploration wells and using the model in a current drilling response of development wells to estimate the current in-situ stress.
[0017] In unconventional wells, wireline or logging data may not be acquired due to budgetary constraints. However, in-situ stress is very important in designing a hydraulic stimulation operation, which is required to enhance permeability for economic production of hydrocarbons. Lack of accurate stress information can lead to wrong selection of the producing intervals which results in lack-luster production performance from the well. This invention with more realistic consideration of in-situ stress estimation provide better results, and will help in planning and executing hydraulic stimulation operation. This will also help in drilling future wells through overburden which require in-situ stress estimates to drill and complete the well successfully.
In-Situ Stress Estimation
[0018] The present invention utilizes fundamental concepts of drilling engineering to link the drilling response with in-situ stress. FIG. 1 illustrates the basic elements of drilling. As drill bits respond to in-situ response and rock strength intersected during drilling, drilling responses such as WOE and RoP have the information linked to in-situ stress and rock strength:
[0000]
S
=
(
1
R
-
2
c
ND
)
(
N
b
W
2
aD
3
)
(
1
)
[0000] where S is equivalent rock strength, R is rate of penetration, N is rotary speed, D is bit diameter, W is weight on bit, b is a dimensionless exponent for the rotary speed effect on RoP, and a and c are dimensionless bit constants.
[0019] However, drilling bits observe effects of in-situ stress and rock strength as one equivalent parameter. In accordance with the present invention, the equivalent parameter is estimated by the development of Relative Rock Strength (RRS) as shown in equation (2):
[0000] RRS=f (effective stress, rock strength) (2)
[0020] This step is summarized as 101 in FIG. 2 . Equations (1) and (3) represent independent approaches of estimating rock strength. The parameters of equations (1) and/or (3) can be varied until stress matches log/core based results.
[0021] Next, RRS is correlated to rock strength estimations from log data and lab test results in the data rich intervals at reservoir depth as shown in equation (3):
[0000] RRS=f ( R, N, W )=ψ{β W +γ( N −η)+ζ( R −κ)} (3)
[0000] where ψ, β, γ, η, ζ, and κ are coefficients relating RRS to unconfined compressive strength C 0 at data rich intervals. Assuming elastic homogeneity, horizontal stress from a uniaxial model is given as
[0000]
S
hmin
-
α
P
p
=
(
S
v
-
α
P
p
)
(
v
1
-
v
)
(
4
)
[0000] where S v is overburden stress, P p is reservoir fluid pressure or pore pressure, α is Biot coefficient, and v is Poisson's ratio.
[0022] A modified version of uniaxial strain model using the RRS is generated at this data rich interval as shown in equations (5) and (6).
[0000]
S
hmin
-
α
P
p
=
(
S
v
-
α
P
p
)
(
v
1
-
v
)
+
a
1
C
0
⇒
S
hmin
-
α
P
p
=
(
S
v
-
α
P
p
)
{
f
(
RRS
)
1
-
f
(
RRS
)
}
+
a
1
RRS
(
4
)
S
Hmax
-
α
P
p
=
(
S
v
-
α
P
p
)
(
v
1
-
v
)
+
a
2
C
0
⇒
S
Hmax
-
α
P
p
=
(
S
v
-
α
P
p
)
{
f
(
RRS
)
1
-
f
(
RRS
)
}
+
a
2
RRS
(
5
)
[0000] where S hmin and S Hmax are minimum and maximum horizontal stress respectively. Poisson's ratio can be defined as a function of RRS at data rich intervals. For practical purposes C 0 is equal to RRS or S. Coefficients a 1 and a2 are obtained empirically at data rich interval. This step is summarized as 201 in FIG. 2 .
[0023] This modified version of stress model is established by the empirical correlation between the stress response from uniaxial strain model using Poisson's ratio generated by RRS and stress results from the frictional equilibrium concept. Frictional equilibrium concept is considered as best technique to estimate the in-situ stress. The final modified version of stress model requires RRS as an input and RRS requires WOB, RoP and RPM as an input, which comes directly from the drilling response.
[0024] In step 301 of FIG. 2 , the overburden stress is obtained by a constant gradient or based on density log. The minimum and maximum horizontal stress are obtained using equations (5) and (6) and verified with Frac gradient values. Once verified, equations (5) and (6) can be used in intervals with drilling data.
[0025] Once the stress model is established at a data rich interval, stress magnitudes are estimated and verified against the minimum principal stress estimated from hydraulic fracture test (extended leak-off test, formation integrity test, diagnostic fracture initiation test, etc.) at some interval not used to establish the stress model. Once this is verified, it is ready to be used in the intervals and wells with drilling response only.
[0026] In closing, it should be noted that the discussion of any reference is not an admission that it is prior art to the present invention, especially any reference that may have a publication date after the priority date of this application. At the same time, each and every claim below is hereby incorporated into this detailed description or specification as additional embodiments of the present invention.
[0027] Although the systems and processes described herein have been described in detail, it should be understood that various changes, substitutions, and alterations can be made without departing from the spirit and scope of the invention as defined by the following claims. Those skilled in the art may be able to study the preferred embodiments and identify other ways to practice the invention that are not exactly as described herein. It is the intent of the inventors that variations and equivalents of the invention are within the scope of the claims, while the description, abstract and drawings are not to be used to limit the scope of the invention. The invention is specifically intended to be as broad as the claims below and their equivalents. | Estimating in-situ stress of an interval having drilling response data is described. Estimating involves obtaining drilling response data of a data rich interval with available data. Estimating relative rock strength as a composite value that includes in-situ stress and rock strength. Estimating a Poisson's ratio from the relative rock strength. Generating a stress model that includes uniaxial strain model using the Poisson's ratio. Verifying the stress model with the available data. Applying the stress models in a non-data rich interval. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the solvent extraction of a diolefin from a mixture of hydrocarbons. More particularly, this invention relates to the extractive distillation of butadiene or isoprene from a mixture of hydrocarbons.
2. Description of the Prior Art
Thermal cracking of hydrocarbons is a petrochemical process that is widely used to produce olefins such as ethylene, propylene, butenes, butadiene, and aromatics such as benzene, toluene, and xylenes.
An olefin production plant is generally composed of a cracking unit and a hydrocarbons unit.
In the cracking unit a hydrocarbonaceous feedstock such as ethane, naphtha, gas oil, or other fractions of whole crude oil is mixed with steam which serves as a diluent to keep the hydrocarbon molecules separated.
This mixture, after preheating, is subjected to hydrocarbon thermal cracking using elevated temperatures (1,450 to 1,550 degrees Fahrenheit or F.) in a pyrolysis furnace (steam cracker or cracker). This thermal cracking is carried out without the aid of any catalyst.
The cracked product effluent of the pyrolysis furnace (furnace) contains hot, gaseous hydrocarbons of great variety (from 1 to 35 carbon atoms per molecule, or C1 to C35 inclusive, both saturated and unsaturated). This product contains aliphatics (alkanes and alkenes), alicyclics (cyclanes, cyclenes, and cyclodienes), aromatics, and molecular hydrogen (hydrogen).
This furnace product is then subjected to further processing in the cracking unit to produce, as products of the olefin plant, various, separate and individual product streams such as hydrogen, ethylene, propylene, fuel oil, and pyrolysis gasoline. After the separation of these individual streams, the remaining cracked product contains essentially C4 hydrocarbons and heavier. This remainder is fed to a debutanizer wherein a crude C4 stream is separated as overhead while a crude C5 and heavier stream is removed as a bottoms product and further processed in a depentanizer.
The crude C4 stream can contain varying amounts of n-butane, isobutane, 1-butene, 2-butenes (both cis and trans isomers), isobutylene, acetylenes, and diolefins such as butadiene (1,2-, 1,3-., cis, and trans isomers), vinyl acetylene, and ethyl acetylene, all of which are known to boil within a narrow range, U.S. Pat. No. 3,436,438. Further, some of these compounds can form an azeotrope. Crude C4's are, therefore, known to be difficult to separate by simple thermal distillation.
The crude C5 stream can contain isoprene, pentanes, pentenes, hexanes, hexenes, and aromatics such as benzene, toluene, and xylenes, and can also be difficult to separate by simple thermal distillation.
The crude C4 and C5 streams are normally further processed in the hydrocarbons unit for the separation of other individual product streams such as butenes, butadiene, isoprene, benzene, toluene, and the like.
The crude C4 stream, after removal of acetylenes, normally goes to a butadiene extraction unit for, among other things, the separation and recovery of butadiene therefrom.
The crude C5 stream is normally sent to an isoprene extraction unit for, among other things, the separation and recovery of isoprene therefrom.
A dominating commercial process for separating butadiene from C4's or isoprene from C5's is known technically as “fractional extraction” but is more commonly referred to as “solvent extraction” or “extractive distillation.” However it is termed, this diolefin separation process employs the technique of altering the relative volatilities of various of the compounds to make easier the separation of those compounds by thermal fractional distillation. More specifically, this process employs an aprotic polar compound (solvent) that has a high complexing affinity toward the more polarizable butadiene or isoprene molecules than, and to the substantial exclusion of, the other olefins in the crude C4 or C5 streams. Known solvents used in this process include acetonitrile, dimethylformamide, furfural, N-methyl-2-pyrrolidone, acetone, dimethylacetamide, and the like. This process and the solvents used in it are well known, U.S. Pat. Nos. 2,993,841 and 4,134,795.
The primary equipment employed in the extractive distillation of butadiene or isoprene from a crude stream is an extractive distillation tower or series of towers followed by a diolefin thermal stripping tower and a separate solvent thermal stripping tower. As will be described in greater detail hereinafter, certain equipment that is ancillary to these towers has, from time to time, been plagued with premature and severe corrosion damage. The corrosion rates experienced have been on the order of about 500 mils per year when typical corrosion rates would have been 1 to 2 mils per year.
Until the advent of this invention, the source of this periodic corrosion problem was unknown, and the corrosion itself was difficult to control because the source of the problem was unknown and the corrosion rate was drastic. Pursuant to this invention, the root cause of this corrosion problem has been discovered and removed in an efficient and cost effective manner.
SUMMARY OF THE INVENTION
Pursuant to this invention, it has been found that the source of the aforesaid corrosion problem in the extractive distillation of butadiene or isoprene was the combination of 1) the presence of ammonia and carbon dioxide in various process streams, coupled with 2) certain operating conditions in the extractive distillation process. It was surprisingly found that elements 1) and 2) aforesaid worked together to keep captive in the process any ammonium carbonate salt that formed from the ammonia and carbon dioxide present in the process.
Due to a unique confluence of normal operating conditions in this process, which conditions will be explained hereinafter, it was discovered that ammonium carbonate salt was not removed with any of the streams that are normally removed from the process. Ammonium carbonate was discovered to largely be kept captive in the process, thereby ultimately causing, again due to the process operating conditions, a buildup of that salt in certain ancillary equipment. Because this salt is corrosive and was never allowed to leave the process, the buildup of salt deposits continued in certain of the equipment to a catastrophic level, thereby causing premature corrosion in, and even failure of that equipment.
BRIEF DISCUSSION OF THE DRAWINGS
FIG. 1 is a flow diagram of a typical commercial diolefin extraction process.
FIG. 2 is the flow diagram of FIG. 1 modified pursuant to this invention.
DETAILED DESCRIPTION OF THE INVENTION
For sake of brevity and clarity, this invention is described in detail hereinafter in respect of the extractive distillation of butadiene. However, this invention applies as well to the extractive distillation of isoprene. Once apprised of the details of this invention, as set forth herein, regarding the extractive distillation of butadiene, one skilled in the art can readily, and without more, apply this invention to the extractive distillation of isoprene. For example, the flow scheme and equipment shown in the Figures described herein below can be applied to isoprene instead of butadiene.
FIG. 1 shows an extractive distillation tower (column) 1 that receives, at a lower level along the height of the tower, crude C4 feed stream 2 , and, at an upper level of the tower, a lean solvent stream 3 . The term “lean solvent” means a solvent stream that contains little or no (essentially no) butadiene (or isoprene). Tower 1 can be a single tower as shown in FIG. 1 or two towers operating in series (not shown), as desired. In tower 1 , streams 2 and 3 are contacted at an elevated temperature with one another in counter current flow to allow the solvent in stream 3 to extract butadiene from stream 2 .
A crude C4 stream 4 (first stream) containing little or no butadiene is removed overhead from tower 1 at a temperature of at least about 125 F, and passed to a tube and shell heat exchanger 6 . In exchanger 6 , stream 4 is cooled to a temperature of less than about 100 F. Cooled stream 4 , i.e., stream 7 , is passed to a recycle drum 8 wherein it is collected for water separation and for distribution purposes. Drum 8 has operatively associated therewith, a water leg 10 which primarily collects water, but which can contain small, but significant, amounts of solvent and C4's, and from which is taken stream 11 (third stream).
A bottoms solvent stream 5 (second stream) that is rich in butadiene, e.g., containing a substantial, if not major, amount of butadiene, is removed from the bottom of tower 1 . Tower 1 has a typical bottoms reboiler circuit for heating and returning a portion of stream 5 to the tower. This circuit is known in the art, and is not shown in FIG. 1 for sake of simplicity only. The normal operating temperature for the bottom of tower 1 is at least about 245 F. Butadiene rich stream 5 is fed to a thermal distillation tower 14 to strip butadiene from its associated solvent.
An essentially butadiene free, cooled crude C4 stream 9 is removed from drum 8 and split to provide a reflux stream 12 that is returned to the interior of tower 1 , and a separate stream 13 that is passed to a water wash unit 47 . In unit 47 , stream 13 is water washed with clean water stream 45 to produce a C4 raffinate product stream 48 that is removed from the process for further processing elsewhere. Water wash 47 also produces a separate stream 49 that is primarily a water stream, but can contain minor amounts (amounts that are worth the effort of reclaiming) of solvent and hydrocarbons (e.g., C4's and/or butadiene).
Butadiene rich solvent stream 5 , containing a substantial, if not major, amount of butadiene, is passed into butadiene stripper tower 14 (first thermal stripping tower) and therein heated to separate butadiene from its associated solvent. Tower 14 is operated at a temperature of at least about 278 F to form a bottoms stream 25 (fifth stream) that is essentially lean solvent suitable for return to lean solvent stream 3 and reuse in tower 1 to extract additional butadiene from fresh, incoming feed 2 . Butadiene rich overhead stream 15 (fourth stream) from tower 14 is passed to a heat exchanger 16 , like that of unit 6 .
In exchanger 16 , stream 15 is cooled to a temperature below about 100 F., and passed as cooled stream 17 to a reflux drum 18 wherein it is collected for water separation and for distribution purposes. Drum 18 has associated therewith a water leg 20 that operates in a manner similar to leg 10 in that it primarily collects water. In the case of leg 20 , water stream 21 (sixth stream) that is removed from that leg can contain small, but significant, amounts of solvent and butadiene, particularly solvent, that are worth the effort of reclaiming.
Butadiene rich stream 19 is removed from drum 18 , passed in part as reflux stream 22 to tower 14 , and passed in part as stream 23 to a separate water wash unit 50 . In unit 50 , stream 23 is contacted with clean water from line 46 . A washed crude butadiene stream 51 that can contain C5 and heavier materials is removed from the process as a product stream to be further treated elsewhere. Water stream 52 can contain hydrocarbons (e.g., butadiene) and solvent in minor amounts that are worth recovering.
As desired, one or more or all of streams 21 , 49 , and 52 can be combined with stream 11 .
Streams 11 , 21 , 49 , and/or 52 can be passed to, and combined in, collection tank 30 , and, then removed from tank 30 as single, combination stream 31 .
Stream 31 is passed to a separate thermal distillation tower 32 (second thermal stripping tower) that is operated to thermally strip solvent plus any associated hydrocarbons (C4's+) from water. Tower 32 is operated with a bottoms temperature of at least about 250 F. to provide a clean (essentially hydrocarbon free) water stream 34 (eighth stream) that is used to provide wash water to streams 45 and/or 46 . In this manner, tower 32 produces an overhead stream 33 (seventh stream) that can contain water, solvent, and one or more C4 and heavier hydrocarbons.
Stream 33 is passed to a heat exchanger 35 , like that of unit 6 . In exchanger 35 , stream 33 is cooled to a temperature of no more than about 120 F. to produce stream 36 . Cooled stream 36 can contain, for example, water, solvent, one or more C4 and heavier hydrocarbons, and is passed to a reflux drum 37 for collection and for distribution purposes. A reflux stream 38 is removed from drum 37 and returned to the interior of tower 32 . A separate stream 39 (ninth stream) is removed from drum 37 and returned to tower 14 for recovery of solvent and hydrocarbons that may be carried by that stream.
Pursuant to this invention, it has been found that fugitive ammonia and carbon dioxide can reach the interior of towers 1 , 14 , and/or 32 . It has further been found that, although ammonia and carbon dioxide could theoretically be purged from the process by way of vents on reflux drums 8 and 18 , this was not, in fact, what was occurring.
It was surprisingly found that the operating temperature of each of towers 1 , 14 , and 32 was such that any ammonium carbonate salt formed from the fugitive ammonia and carbon dioxide present in these towers was dissociated by their operating, e.g., bottom, temperatures so that essentially all the ammonia and carbon dioxide present in each tower was passed out of the tower as vapor in its overhead stream, i.e., streams 4 , 15 , and 33 . It should be understood that in a commercial process such as the one described in FIG. 2 , the dissociation temperature of ammonium carbonate is not a precise temperature as would be found in the pristine environment of a chemical laboratory. It was found that this dissociation temperature varied widely depending on the location of the ammonium carbonate in the process of FIG. 2 . For example, the dissociation temperature of ammonium carbonate was affected substantially by the presence or absence of other chemical constituents present at a particular location in the process of FIG. 2 . Accordingly, it was found that the dissociation temperature range to be used in the practice of this invention is from about 120 to about 140 F., the precise laboratory dissociation temperature of 136 F. notwithstanding. If one operated on the premise that ammonium carbonate dissociated essentially at 136 F., this invention would not have been discovered. For example, one skilled in the art would not have expected dissociated ammonium carbonate to be present at the 125 F. overhead temperature of tower 1 , but it was.
It was further found that the operating temperature of the heat exchangers for each such tower, i.e., exchangers 6 , 16 , and 35 , was such that the formation of ammonium carbonate from ammonia and carbon dioxide was promoted. This caused a preferential deposition of ammonium carbonate solely in those heat exchangers and was found to be the proximate cause of the premature corrosion and catastrophic failures those exchangers were, from time to time, experiencing
Because towers 1 , 14 , and 32 conventionally operate at a temperature that promotes the dissociation of ammonium carbonate to ammonia and carbon dioxide vapor, any and all ammonia and carbon dioxide that reached the process in general, and these towers in particular, was preferentially forced into overhead streams 4 , 15 , and 33 , and, therefore, into their associated overhead heat exchangers 6 , 16 , and 33 . Accordingly, all fugitive ammonia and carbon dioxide that reached the process was inadvertently perpetually kept captive in the process as a soluble solution from water boots and water wash towers that fed tower 32 and recycled back to tower 14 by way of line 39 or as an ammonium carbonate deposition on the cooler internal surfaces in heat exchangers 6 , 16 , and 33 , i.e., exchanger internal surfaces that were below the temperature at which ammonium carbonate dissociates.
The fugitive ammonia and carbon dioxide can be present in feed 2 as it enters the process and/or can be generated in situ in the process. For example, it has been found that certain of the solvents such as acetonitrile can produce some ammonia under the operating conditions of the solvent extraction process itself.
Further pursuant to this invention, it has been found that the fugitive carbon dioxide in the solvent extraction process can be converted 1) to a stable carbonate salt that will not dissociate at the operating, particularly the operating, temperatures of towers 1 , 14 , and 32 , and 2) to the substantial exclusion of the formation of ammonium carbonate.
This stable carbonate salt that is not dissociated under the operating conditions of the process can then be removed from the process by way of a purge stream, thereby 1) freeing what would otherwise be perpetually captive ammonia and carbon dioxide, and 2) removing the fugitive carbon dioxide from the process itself. The fugitive ammonia vapor is thereby left as ammonia gas via vents on reflux drums 8 and 18 or in a separate purge stream as well.
The stable salt of this invention can be formed by adding at least one base compound to at least one stream in the extractive distillation process in an amount sufficient to form the desired stable salt, to the essential (substantial) exclusion of the formation of the unstable ammonium carbonate salt.
The stable carbonate salt of this invention can be formed by adding to the process at least one of sodium hydroxide or potassium hydroxide in an amount of from about 4 parts per million (ppm) to about 0.4 weight percent based on the total weight of the stream being treated.
FIG. 2 shows the process of FIG. 1 modified pursuant to this invention. FIG. 2 shows that the base compound or compounds used to form the desired stable carbonate salt can, by way of example, be added to one or more or all of solvent stream 3 by way of conduit 50 , to feed stream 31 by way of conduit 51 , to reflux stream 38 by way of conduit 52 , to water stream 34 by way of conduit 53 , and to water stream 21 by way of conduit 54 . The compound(s) added to the process can be inserted into the process in streams and equipment other than that shown in FIG. 2 and still fall within the scope of this invention.
The primary goal of this invention is to add such at least one base compound to one or more locations in the process in a aggregate (total) amount that is sufficient to prevent the formation of ammonium carbonate to any significant extent in the extractive distillation process as a whole. Extractive distillation processes and equipment configurations in various plants can vary from that shown in FIG. 2 so that it is impossible to specify all the points of introduction of the ammonium carbonate preventing base compound(s), or the total amount of such compound(s) that should be added to achieve the inventive results of this invention. However, once apprised of this disclosure, one skilled in the art will readily be able to determine where and in what amount to inject the ammonium carbonate suppressing base compound(s) in a specific process to achieve the desired results of this invention.
FIG. 2 also shows that the stable carbonate salt formed pursuant to this invention, and the carbon dioxide it ties up, can be removed from the extractive distillation process completely by way of a water purge stream 55 from bottoms stream 34 of tower 32 . Other removal sites can be used, and will be obvious to one skilled in the art.
EXAMPLE
A process as shown in FIG. 2 was carried out in a commercial butadiene solvent extraction process.
Feed stream 2 for extractive distillation tower 1 contained about 2 ppm ammonia and about 5 ppm carbon dioxide.
Sodium hydroxide solution is contacted with feed stream 2 in the amount of about 4,000 ppm, based on the total weight of stream 2 .
Within one month of operation using bottom temperatures for towers 1 , 14 , and 32 of about 245 F., about 278 F., and about 250 F., respectively, no ammonium carbonate was formed in any of heat exchangers 6 , 16 , and 35 . | A method for reducing corrosion in a diolefin extractive distillation process comprising preventing the formation of ammonium carbonate by promoting the formation of a carbonate salt that does not dissociate in the ammonium carbonate dissociation temperature range of that extractive distillation process. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under Title 35, U.S.C. §119(e) of U.S. Provisional Application Ser. No. 60/943,979, entitled MODULAR VIBRATORY PILE DRIVER, filed on Jun. 14, 2007.
BACKGROUND
[0002] 1. Field of the Disclosure
[0003] The present disclosure relates to pile driving equipment. More particularly, the present disclosure relates to a modular vibratory side grip pile driver system and method for assembly.
[0004] 2. Description of the Related Art
[0005] Vibratory pile drivers are used in a plurality of applications to drive pile, such as sheet pile, pipes, I-beams, H-beams, and poles, for example, into the ground. The pile driver may be mounted on an excavator and include articulating arms and side-gripping jaws to facilitate the pile driving process.
[0006] Current side grip vibratory pile drivers have the disadvantage that they are designed for driving only one type of pile. Therefore, if it is desired to switch from driving sheet pile to H-pile, for example, a separate unit must be employed. This leads to significant increased cost at a job site and requires that the construction company inventory more than type of pile driver for use at its various job sites.
SUMMARY
[0007] The modular vibratory pile driving system of the present invention comprises a base unit having a housing, a vibratory gear case and a mounting base rigidly connected to the housing. It also includes two jaws that are spaced apart longitudinally wherein the jaws include jaw halves that are movable relative to each other to enable a pile to be gripped. In a preferred embodiment, each of the jaws includes a stationary jaw half rigidly connected to the mounting base and a pivotable jaw rotatably connected to the mounting base and caused to open and close through the action of one or more hydraulic cylinders. The pile driver system also includes a set of gripping assemblies having different gripping profiles adapted for gripping a variety of different pile profiles. These gripping assemblies are interchangeable so that the same base unit can be utilized to drive a variety of pile profiles. In one embodiment, the gripping assemblies include elements that are removably attached to the stationary jaw halves as well as removable pivot arms including gripping profiles that match the profiles of the gripping assemblies mounted to the stationary jaws.
[0008] Advantageously, the modular vibratory pile driver system eliminates the need to obtain a plurality of pile drivers matching the types of pile to be driven. Instead, the modular vibratory pile driver uses the same housing and gear case for all types of pile and utilizes modular sets of gripping assemblies to facilitate driving different types of pile, thereby reducing costs and saving time. Further, the modular vibratory pile drivers of the present disclosure facilitate centering of the pile with the pile driver, thereby enhancing the efficiency of energy transfer to the pile and reducing the stress on the gear case of the pile driver. Moreover, the modular vibratory pile driver facilitates straight driving of the pile because the centerline of the pile matches the centerline provided by the selected modular gripping assembly set.
[0009] In one form thereof, the present invention is a modular side grip vibratory pile driver system comprising a housing that includes a mounting base comprising first jaw halves. A vibratory gear case is mounted to the housing and a pivotable arm assembly forming two second jaw halves is pivotally connected to the housing. The respective first and second jaw halves form a pair of spaced apart jaws adapted for gripping a pile at two longitudinally spaced apart locations. An attachment assembly connects the housing to a construction machine. The housing is rotatably connected to the attachment assembly and rotatable between a first position wherein the jaws are oriented vertically and spaced apart horizontally and a second position wherein the jaws are oriented horizontally and spaced apart vertically. The jaws are open thereby forming a gap so that a pile can enter the jaws laterally. A plurality of sets of gripping assemblies having different gripping profiles adapted for gripping a variety of different pile profiles are interchangeably connected to and form the pile gripping elements of the jaws. The jaws include a single set of the interchangeable gripping assemblies detachably and interchangeably connected thereto.
[0010] In another form thereof, the invention constitutes a method of changing a modular side grip vibratory pile driver from a first configuration to a second configuration. One of the sets of gripping assemblies is selected from the plurality of sets wherein the selected gripping assembly accommodates the profile of a pile to be driven and this gripping assembly is substituted for the current set of gripping assemblies forming the gripping surfaces on each of the jaws. In one embodiment each of the jaws comprises a stationary jaw half and a removably rotatable jaw half and the step of substituting comprises replacing the current rotatable jaw halves with rotatable jaw halves from the plurality of sets having a gripping profile that accommodates the profile of the pile to be driven. The gripping assembly on the stationary jaw is replaced with a gripping assembly from the plurality of sets that accommodates the pile profile.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The above-mentioned and other features of the disclosure, and the manner of attaining them, will become more apparent and will be better understood by reference to the following description of embodiments of the disclosure taken in conjunction with the accompanying drawings, wherein:
[0012] FIG. 1 is a perspective view of a first embodiment modular side grip vibratory pile driver of the present disclosure, further illustrating a sheet pile clamped in the jaw assembly of the pile driver;
[0013] FIG. 2 is another perspective view of the modular vibratory pile driver of FIG. 1 ;
[0014] FIG. 3 is a side view of the modular vibratory pile driver of FIG. 1 ;
[0015] FIG. 4 is a top view of the modular vibratory pile driver of FIG. 1 ;
[0016] FIG. 5 is another perspective view of the modular vibratory pile driver of FIG. 1 , further illustrating the hydraulic cylinders used to power the jaw assembly of the pile driver;
[0017] FIG. 6 is an exploded view of a portion of the modular vibratory pile driver of FIG. 1 ;
[0018] FIG. 7 is another exploded view of a portion of the modular vibratory pile driver of FIG. 1 ;
[0019] FIG. 8 is a perspective view of a second embodiment modular side grip vibratory pile driver of the present disclosure, further illustrating a large diameter pipe clamped in the jaw assembly of the pile driver;
[0020] FIG. 9 is another perspective view of the modular vibratory pile driver of FIG. 8 ;
[0021] FIG. 10 is a side view of the modular vibratory pile driver of FIG. 8 ;
[0022] FIG. 11 is a top view of the modular vibratory pile driver of FIG. 8 ;
[0023] FIG. 12 is a perspective view of a third embodiment modular side grip vibratory pile driver of the present disclosure, further illustrating a small diameter pipe clamped in the jaw assembly of the pile driver;
[0024] FIG. 13 is another perspective view of the modular vibratory pile driver of FIG. 12 ;
[0025] FIG. 14 is another perspective view of the modular vibratory pile driver of FIG. 12 ;
[0026] FIG. 15 is a side view of the modular vibratory pile driver of FIG. 12 ;
[0027] FIG. 16 is a top view of the modular vibratory pile driver of FIG. 12 ;
[0028] FIG. 17 is an exploded view of a portion of the modular vibratory pile driver of either FIG. 8 or FIG. 12 ; and
[0029] FIG. 18 is another exploded view of a portion of the modular vibratory pile driver of either FIG. 8 or FIG. 12 .
[0030] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the disclosure and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION
[0031] Referring now to FIGS. 1-5 , modular vibratory side grip pile driver 30 is shown and generally includes housing 31 , first assembly 35 , and jaw assembly 50 . Pile driver 30 may be used to grasp and drive sheet or beam, e.g., I-beam and H-beam, pile 33 into the ground. Housing 31 includes vibratory gear case 36 and mounting base 37 . Bracket 41 connects housing 31 to attachment assembly 32 which is used to attach pile driver 30 to an excavator or other suitable construction machine for mounting pile driver 30 thereon. Rotational connector 38 is provided along with attachment plate 32 to permit rotation of housing 31 relative to the excavator. Rubber insulators 34 are included on the inner portions of housing 31 to reduce vibration caused by gear case 36 during use of pile driver 30 and to prevent such vibration from vibrating a portion of the excavator. Pile driver 30 is a modification of the Model SPM 15 vibratory pile driver manufactured by Hercules Machinery Corporation of Fort Wayne, Indiana, and incorporates most of the mechanism of such pile driver except for the structure that adds the modularity feature. In other words, the base unit remains the same for the various configurations adapted to grip certain types of sheet, pipe, H or other pile.
[0032] A further example of a side grip vibratory pile driver is disclosed in U.S. Reissue Pat. No. RE37,661. The disclosure of this patent is specifically incorporated herein by reference.
[0033] Mounting assembly 35 includes a mounting base 37 rigidly connected to the housing 31 and forming a first pair of jaw halves 37 a and first gripping assembly 39 . In an exemplary embodiment, mounting base 37 having jaws 37 a is stationary relative to gear case 36 . In an alternative embodiment, mounting base 37 is movable relative to gear case 36 . Referring to FIGS. 6 and 7 , first gripping assembly 39 includes first gripping mount 53 which may include a plurality of slots 54 for mating engagement with a plurality of fasteners 55 for securing first gripping mount 53 to mounting base 37 . Slots 54 are provided instead of holes or apertures sized to accept fasteners 55 because slots 54 allow first gripping mount 53 to move and slightly adjust front-to-back and side-to-side relative to mounting base 37 , thereby allowing first gripping mount 53 to align with arm gripping assembly 52 in a complementary engagement to securely hold sheet pile 33 . First gripping assembly 39 also includes two contact plates 47 for providing direct contact with sheet pile 33 . In an exemplary embodiment, contact plates 47 have a knurled or otherwise roughened surface to enhance and facilitate gripping of sheet pile 33 . Each contact plate 47 is assembled to first gripping mount 53 with rubber washer 46 , bolt 43 , spring 45 , and nut 44 . Spring 45 advantageously allows contact plate 47 to adjust during engagement of sheet pile 33 .
[0034] Referring now to FIGS. 2 , 3 , 5 , 6 , and 7 , jaw assembly 50 comprises a pair of jaws including first gripping assembly 39 , arms 40 , and arm gripping assemblies 52 . Each arm 40 is pivotally and detachably affixed to housing 31 and preferably to an extension of mounting base 37 via pin 48 which creates a pivot joint of arm 40 relative to base 37 . Each arm 40 is connected via pin 49 to hydraulic cylinder 42 which is connected to a hydraulic system (not shown) of the excavator to which pile driver 30 is attached to provide pivot control of arms 40 . Each arm 40 includes an arm gripping assembly 52 detachably affixed thereto. Each arm gripping assembly 52 includes contact plate 47 which is connected to arm 40 via rubber washer 46 , bolt 43 , spring 45 , and nut 44 .
[0035] Referring now to FIGS. 3 , 5 , 6 , and 7 , pile driver 30 preferably includes lower jaws 51 which provide mating contact plates 47 for gripping a top portion of sheet pile 33 to facilitate final driving of pile 33 into the ground.
[0036] In operation and referring to FIGS. 1-7 , jaw assembly 50 provides side-gripping force on pile 33 in which arms 40 are hydraulically actuated to grasp and move sheet pile 33 into a desired location for driving pile 33 into the ground. The upper and lower sets of jaw halves forming the jaws of jaw assembly 50 are open so that a pile 33 can enter the jaws laterally and then be gripped when the jaws 50 are closed. Arms 40 secure pile 33 while gear case 36 provides vibration while the excavator guides modular vibratory pile driver 30 towards the ground and sheet pile 33 into the ground. Modular vibratory pile driver 30 defines centerline 60 ( FIG. 4 ) along which the most focused and concentrated power is developed in pile driver 30 . Advantageously, centerline 60 matches centerline 61 of sheet pile 33 , thereby enhancing the efficiency of energy transfer to pile 33 and reducing stress on gear case 36 . Moreover, modular vibratory pile driver 30 facilitates substantially straight driving of pile 33 because centerline 60 matches centerline 61 .
[0037] Referring now to FIGS. 8-11 , modular vibratory pile driver configuration 130 is shown and is substantially identical to modular vibratory pile driver 30 , described above with reference to FIGS. 1-7 , except for arms 140 , arm gripping assembly 152 , and first gripping assembly 139 , as described below that have been installed in place of arms 40 and gripping assemblies 52 and 39 , respectively. In other words, housing 31 remains the same in the configuration shown in FIGS. 8-11 as compared with the configuration shown in FIGS. 1-7 .
[0038] Referring still to FIGS. 8-11 , modular vibratory side grip pile driver 130 configured as a cylindrical pile driver is shown and generally includes housing 31 , assembly 135 , and jaws 150 . Pile driver 130 may be used to grasp and drive large pipe pile 133 into the ground or other desirable location.
[0039] Mounting assembly 135 includes mounting base 37 and first gripping assembly 139 . First gripping assembly 139 includes first gripping mount 153 detachably mounted to base 37 . First gripping assembly 139 also includes two contact surfaces 147 for providing direct contact with pile 133 . In an exemplary embodiment, contact surfaces 147 are arcuate to match the outer diameter of pile 133 and are knurled to enhance and facilitate gripping of pile 133 .
[0040] Jaw assembly 150 includes mounting base 37 , first gripping assembly 139 , arms 140 , and arm gripping assemblies 152 . Each arm 140 is pivotally and detachably affixed to base 37 via pin 48 which creates a pivot joint of arm 140 relative to mounting base 37 . Each arm 140 is connected via pin 49 to hydraulic cylinder 42 which is connected to a hydraulic system (not shown) of the excavator to which pile driver 130 is attached to provide pivot control of arms 140 . Each arm 140 includes an arm gripping assembly 152 detachably affixed thereto. Arm gripping assembly 152 includes arm gripping mount 156 with contact surfaces 147 for providing direct contact with pile 133 . In an exemplary embodiment, contact surfaces 147 are arcuate to match an outer diameter of pile 133 and are knurled to enhance and facilitate gripping of pile 133 .
[0041] Arm gripping assembly 152 and first gripping assembly 139 encircle pile 133 and form pipe grip engagement 157 therebetween, as shown in FIG. 11 . Pipe grip engagement 157 between arm gripping assembly 152 and first gripping assembly 139 prevents deformation of pile 133 when jaw assembly 150 is clamped shut and also enhances the hold of pile 133 in pile driver 130 . Referring now to FIG. 10 , pile driver configuration 130 may optionally include lower jaws 151 which provide mating contact surfaces 147 for gripping a top portion of pile 133 for final driving of pile 133 into the ground. When pile 133 is engaged by only lower jaws 151 ( FIG. 10 ) to finally drive pile 133 into the ground, the interlocking engagement provided by pipe grip engagement 157 prevents arms 140 from flopping around due to the vibration.
[0042] In operation and referring again to FIGS. 8-11 , jaw assembly 150 provides side gripping force on pile 133 in a substantially similar manner as jaw assembly 50 , described above with respect to FIGS. 1-7 . Advantageously, modular vibratory pile driver configuration 130 defines centerline 160 ( FIG. 11 ) which substantially matches centerline 161 of pile 133 .
[0043] To switch from the configuration shown in FIGS. 1-7 to the configuration shown in FIGS. 8-11 , a user of pile driver 30 removes pins 48 , 49 associated with arms 40 . Arms 40 are then removed from mounting base 37 . Arms 140 may then be attached to mounting base 37 with pins 48 , 49 to form configuration 130 which is now equipped to grip pile 133 .
[0044] Referring now to FIGS. 12-16 , modular vibratory pile driver configuration 230 is shown and is substantially identical to configurations 30 , 130 , described above with reference to FIGS. 1-7 and 8 - 11 , except for arm gripping assembly 252 and first gripping assembly 239 , as described below, i.e., all of the structure, including housing 31 , remains the same in the configuration shown in FIGS. 12-16 as compared with the configurations shown in FIGS. 1-7 and 8 - 11 , and arms 140 remain the same in the configuration shown in FIGS. 12-16 as compared with the configuration shown in FIGS. 8-11 . Replacement gripping assemblies 235 , 239 , 250 and 252 , gripping mounts 253 and 256 and contact services 247 are sized to match the smaller diameter cylindrical pipe pile 233 .
[0045] In operation, jaw assembly 250 provides side gripping force on pile 233 in a substantially similar manner as jaws 50 , 150 , described above with respect to FIGS. 1-7 and 8 - 11 . Advantageously, modular vibratory pile driver 230 defines centerline 260 ( FIG. 16 ) which substantially matches centerline 261 of pile 233 .
[0046] To switch from the embodiment shown in FIGS. 8-11 to the embodiment shown in FIGS. 12-16 , the user removes fasteners 155 from first gripping assembly 139 and arm gripping assemblies 152 to detach first gripping assembly 139 and arm gripping assemblies 152 . First gripping assembly 239 and arm gripping assemblies 252 may then be respectively attached to mounting base 37 and arms 140 with fasteners 255 , thereby forming configuration 230 which is equipped to grip smaller diameter pile 233 .
[0047] Referring to FIGS. 17 and 18 , first gripping assembly 139 includes first gripping mount 153 which includes a plurality of slots 154 for mating engagement with a plurality of fasteners 155 for detachably affixing first gripping mount 153 to mounting base 37 . Slots 154 are provided instead of holes or apertures sized to accept fasteners 155 because slots 154 allow first gripping mount 153 to move and slightly adjust front-to-back and side-to-side relative to base 37 , thereby allowing first gripping mount 153 to align with arm gripping assembly 152 to securely hold pile 133 . First gripping assembly 139 also may include two contact surfaces 147 for providing direct contact with pile 133 .
[0048] Piles 133 , 233 may be formed as Schedule 40 piping having an outer diameter as small as approximately ½″, 1″, 1½″, 2″, 3″, 4″, or 4½″, or as large as 40″, 30″, 20″, 15″, 10″, 9″, 8″, 7″, 6⅝″, 6″, 5½″, or 5″.
[0049] In operation, modular vibratory pile driver configurations 30 , 130 , 230 provide flexibility and options depending on the type of pile to be driven into the ground. For example, pile driver configuration 30 may be used to drive a sheet pile, e.g., sheet pile 33 , into the ground. Subsequently, a user of pile driver 30 may want to drive a pipe pile. Advantageously, the user simply removes arms 40 from pile driver 30 and replaces them with arms 140 using the same attachments, i.e., pins 48 , 49 , to attach arms 140 to mounting base 37 and hydraulic cylinders 42 to form configuration 130 . In one embodiment, arms 140 have arm gripping assembly 152 detachably affixed thereto and mounting base 37 has complementary first gripping assembly 153 detachably affixed thereto to accommodate large pipe pile 133 . Alternatively, arms 140 have arm gripping assemblies 252 detachably affixed thereto and base 37 has complementary first gripping assembly 253 detachably affixed thereto to accommodate small pipe pile 233 . Therefore, arms 40 , 140 , arm gripping assemblies 152 , 252 , and first gripping assemblies 153 , 253 are modular attachments that may be interchanged depending on the size and type of pile to be driven into the ground.
[0050] Advantageously, the modular vibratory pile driver configuration described in the present application provide various degrees of modularity to provide variability and flexibility in selecting components to provide the optimum outcome for a desired pile driving procedure. For example, the pivotable arms are replaced with a different set of pivotable arms. In another example, the arms remain attached to the first portion but the gripping assemblies are replaced with a different set of gripping assemblies. Advantageously, the modular vibratory pile driver configurations of the present application all utilize the same housing 31 including gear case 36 and mounting base 37 . Thus, a user of the pile driver only needs to purchase a single base unit, instead of purchasing three or more separate pile drivers. The modular attachments of the present application are advantageously used interchangeably with the base unit to provide a modular side grip vibratory pile driver. Therefore, the overall cost of the pile driving system is substantially reduced. Moreover, the efficiency of the pile driving system is maintained.
[0051] While this disclosure has been described as having exemplary designs, the present disclosure can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and which fall within the limits of the appended claims. | A modular side grip vibratory pile driver system having a housing, a vibratory gear case and a pair of jaws adapted to grip a variety of pile profiles. The housing is rotatably connected to a construction machine such that the jaws can be moved from a position wherein the jaws are oriented vertically and spaced apart horizontally to a position wherein the jaws are oriented horizontally and spaced apart vertically. A plurality of sets of gripping assemblies having different gripping profiles are interchangeably connected to the jaws. | 4 |
PRIORITY CLAIM
[0001] The present application claims the priority to the U.S. Provisional Application Ser. No. 61/245,364, entitled “EUS-FNA Stylet Withdrawal into Handle” filed on Sep. 24, 2009. The specification of the above-identified application is incorporated herewith by reference
BACKGROUND
[0002] Biopsies may be performed via Endoscopic Ultrasound Fine Needle Aspiration (“EUS-FNA”) to obtain cells or small samples of tissue from, for example, the breast or liver for cytology studies, endoscopy or oncology. With current EUS-FNA devices, a stylet is inserted through the lumen of a needle to the distal end thereof to prevent tissue from entering the needle as the needle passes through tissue along an insertion path before a target site is reached. When the needle has reached the target site, the stylet is withdrawn proximally from the device to open the lumen. The needle is then inserted into the target tissue and negative pressure may be applied therethrough to aspirate sample tissue from the distal end of the needle further into the lumen. After the sample has been obtained and the needle has been removed from the body, the stylet is passed distally through the lumen to push the sample tissue out of the distal end of the needle (e.g., onto a slide or into another collection area). In many instances, EUS-FNA devices yield samples that are too small, which are contaminated during the biopsy procedure or which are otherwise flawed to the extent that thorough analysis and diagnosis is not possible. In these cases, the tissue must be resampled increasing the time and expense associated with the EUS-FNA procedure. Furthermore, present EUS-FNA devices require removal of the stylet in order to receive a biopsy sample. This withdrawal can cause kinking of the stylet and may result in the stylet becoming unsterile, preventing reinsertion thereof into the EUS-FNA device. In such cases, a new EUS-FNA device must be employed to acquire further biopsy samples.
SUMMARY OF THE INVENTION
[0003] The present invention is directed to a medical device comprises a needle configured for insertion into a body and defining a needle lumen extending therethrough from a proximal end opening to a distal end opening and a handle connected to a proximal end of the needle and including a stylet receiving lumen therein, the stylet receiving lumen being open to a proximal end of the needle lumen. The medical device also comprises a stylet movable between a retracted configuration in which a distal end of the stylet is received within the stylet receiving chamber and an extended configuration in which the distal end of the stylet is received within the distal opening of the needle lumen sealing the distal opening, wherein, when withdrawn proximally into the stylet receiving lumen, the stylet is coiled within the chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a partial cross-sectional view of a device according to the present invention.
DETAILED DESCRIPTION
[0005] The present invention, which may be further understood with reference to the following description and the appended drawings, relates to an apparatus and method for obtaining tissue samples and, more particularly relates to EUS-FNA devices. The needle design of the present invention which may be used in substantially all procedures employing EUS-FNA devices further increases the efficacy of EUS-FNA procedures by permitting the procurement of tissue samples from a living body without removing the stylet from the device.
[0006] Devices and methods according to the present invention employ an FNA device comprising a stylet which, when retracted proximally thereinto, assumes a storage configuration such as a coiled configuration within a handle of the FNA device eliminating the need to remove the stylet completely from the FNA device when a sample is to be obtained. In this manner, the stylet may be easily retracted to a proximal portion of a needle without having to remove the stylet from the FNA device altogether. It is noted that the use of the term distal herein refers to a direction approaching a target site in a patient in an operative configuration and the term proximal refers to a direction approaching a user of the device (e.g., a physician) with a proximal portion of the device remaining external to the patient.
[0007] As shown in FIG. 1 , a device 100 according to an exemplary embodiment of the present invention for use with an EUS-FNA actuation mechanism (not shown) comprises an elongated hollow body 102 with a puncturing point 104 at a distal end thereof. It is noted however, that the device 100 may take any other shape and may also comprises a blunt distal end without deviating from the scope of the present invention. The elongated body 102 may be composed of any of a variety of suitable materials known in the art such as, for example, stainless steel and nitinol. The elongated body 102 includes a first lumen 106 extending therethrough to a distal opening 108 at the puncturing point 104 . A handle 110 formed at a proximal end of the body 102 and having an outer diameter greater than an outer diameter of the elongated body 102 remains outside the body during use. The handle 110 may comprise a second lumen 112 extending therethrough and open to the first lumen 106 , a diameter of the second lumen 112 being substantially equivalent to or greater than a diameter of the first lumen 106 . In one embodiment, the second lumen 112 follows a substantially coiled path through the handle 110 and may be formed with any number of turns suitable to accommodate a required length of the stylet 120 therethrough. The handle 110 may be integrally formed with the elongated body 102 or, alternatively, may be bonded thereto using any known bonding technique including gluing, insert molding and other permanent or temporary fixation techniques. In the embodiment shown, the handle 110 is connected to the elongated body 102 via a tapered portion 118 . It is noted however, that the part of the elongated body 102 which remains outside the body during use may take any shape as would be understood by those skilled in the art. The device 100 also comprises a stylet 120 configured to seal the first lumen 106 extending through during an initial penetration into target body tissue, the stylet 120 minimizing the entry of blood, tissue, etc. into the first lumen 106 before a target sampling site has been reached, as those skilled in the art will understand. An exemplary stylet 120 according to the present invention can be formed of a material known in the art including, but not limited to Nitinol, stainless steel, elgiloy, titanium, tantalum and polymers. The stylet 120 may have shape-memory properties as would be understood by those skilled in the art, the stylet 120 being formed to assume a substantially coiled memorized shape. In such an embodiment, the second lumen 112 may be formed with a substantially cylindrical shape instead of the substantially coiled shape of FIG. 1 , an outer diameter of the coiled shape of the stylet 120 being dimensioned to frictionally engage an inner wall of the second lumen 112 . It is further noted that the handle 110 may also be formed without a second lumen 112 . Rather, the handle 110 may be formed as a hollow substantially cylindrical element having a substantially cylindrical hollow core. In this embodiment, the stylet 120 may be retracted into the handle 110 within which it will assume its shape-memorized coiled configuration, as those skilled in the art will understand. In yet another embodiment of the present invention, the handle 110 may be formed with a grooved patterns molded on an inner wall thereof, the pattern configured to guide the stylet 120 into a retracted (i.e., coiled) configuration. An inner wall of the first lumen 106 and the handle 110 be provided with a hydrophilic coating or other biocompatible lubricious coating to ease insertion of the stylet 120 therethrough.
[0008] An outer diameter of a distal portion of the first lumen 106 is only slightly larger than an outer diameter of the stylet 120 so that the stylet 120 substantially seals the first lumen 106 when it is advanced to the distal end of the first lumen 106 . In an alternate embodiment, a distal tip of the stylet is of a higher durometer than a proximal portion thereof in order to maintain an overall flexibility of the stylet 120 while still occluding the distal end of the first lumen 106 . In one embodiment, the increased durometer portion of the stylet is greater than approximately 2.54 cm. in length, although this value may be changed to affect the flexibility of the stylet accordingly. In an exemplary embodiment of the invention, the inner diameter of the first lumen 106 is substantially constant. In another embodiment, however, the inner diameter of the first lumen 106 may increase at a point proximal of the distal end of the first lumen 106 to house sampled body tissue and facilitate aspiration. Such a device is disclosed in U.S. Provisional Application No. 61/235,465 entitled “Flared Needle for EUS Fine Needle Aspiration Device” filed Aug. 20, 2009, the entire contents of which are incorporated herein by reference. The second lumen 112 is substantially cylindrical and forms a central opening through which the stylet 120 may be retracted. A proximal portion of the first lumen 106 housed within the handle 110 comprises a Y-adaptor leading to a third lumen 114 . The third lumen extends out of the handle 110 and comprises an opening 116 at a proximal end thereof for the connection with a syringe (not shown) or other source of aspiration. The opening 116 may be formed with a seal (not shown) to prevent the entry of foreign matter thereinto when not connected to a source of aspiration. The first lumen 106 may terminate within the handle 110 at a location proximal of an opening 118 of the third lumen 114 , a proximal end of the first lumen 106 further comprising a valve 117 such as a touhy-borst valve. The touhy-borst valve 117 may be configured to maintain a position of the stylet 120 within the first lumen 106 while permitting advancement and retraction thereof. Alternatively, any other suitable valve may be used in place of the touhy-borst valve 117 including, but not limited to duckbill valves, gel-filled valves, foam-filled valves, ball valves and stopcocks. Accordingly, although portions of the stylet 120 received within the first lumen 106 are constrained to a substantially linear arrangement, portions of the stylet 120 which are drawn proximally into the second lumen 112 assume the coiled shape defined by the coils of the second lumen 112 . In one embodiment, a pitch of the coils of the second lumen 112 may preferably be selected to be substantially equal to a diameter of the stylet 120 so that adjacent turns of the coil contact one another and a length of the stylet 120 which may be received within the second lumen 112 is maximized. Furthermore, a length of the second lumen 112 is preferably chosen so that, when the stylet 120 is fully retracted proximally, the distal end of the stylet 120 is withdrawn into the second lumen 112 proximal of the third lumen 114 . This moves the distal end of the stylet 120 out of the first lumen 106 permitting the passage of fluids and/or tissue through the third lumen. A proximal end of the third lumen 114 may be connected to a source of negative pressure such as a vacuum pump, syringe, etc. to aspirate sampled tissue through the first lumen into the third lumen 114 . A seal (not shown) may also be provided at this proximal end to ensure proper transfer of a vacuum pressure therethrough.
[0009] The stylet 120 may be advanced and retracted within the device 100 by actuating an actuating mechanism (not shown) located on a proximal end of the handle 110 . The actuating mechanism (not shown) may be formed of a design including, but not limited to, a rotatable portion (not shown) on the handle 110 , rotation of the rotatable portion causing distal advancement or proximal retraction of the stylet 120 or a motorized component configured to control movement of the stylet 120 . In one embodiment, the actuating mechanism may be a ratchet mechanism or pulley to permit linear actuation of the stylet 120 , as those skilled in the art will understand. In an operative configuration, the actuating mechanism is configured to advance the stylet 120 out of the second lumen 112 into the first lumen 106 and through the first lumen 106 until a distal end of the stylet 120 is received in the distal opening of the first lumen 106 . When a target tissue site has been reached, the stylet 120 is retracted so that a distal end thereof is located proximal to the opening 118 of the third lumen 114 so that a source of negative pressure applied to the third lumen 114 permits sampling of tissue or other biological matter thereinto. It is noted that although the present invention has been described with respect to a coiled path of the second lumen 112 through the handle 110 , the second lumen 112 may follow any path through the handle without deviating from the scope of the present invention.
[0010] It is noted that, although the present invention has been described with reference to specific exemplary embodiments, those skilled in the art will understand that various modifications and changes may be made to the embodiments. For example, the exemplary embodiments of the present invention call for a path of the stylet through the handle that is longer than a longitudinal length of the handle itself to permit retraction of the stylet thereinto without removing the stylet from the body. Thus, the stylet may follow any path through the handle without deviating from the scope of the present invention. The specifications are, therefore, to be regarded in an illustrative rather than a restrictive sense. | A medical device comprises a needle configured for insertion into a body and defining a needle lumen extending therethrough from a proximal end opening to a distal end opening and a handle connected to a proximal end of the needle and including a stylet receiving lumen therein, the stylet receiving lumen being open to a proximal end of the needle lumen. The medical device also comprises a stylet movable between a retracted configuration in which a distal end of the stylet is received within the stylet receiving chamber and an extended configuration in which the distal end of the stylet is received within the distal opening of the needle lumen sealing the distal opening, wherein, when withdrawn proximally into the stylet receiving lumen, the stylet is coiled within the chamber. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a sealing arrangement for a bearing compartment in a turbine engine and more particularly, to a coated seal for use therewith.
BACKGROUND
A bearing compartment in a multiple spool gas turbine engine may contain oil that lubricates bearings that support an inner rotor shaft and an outer rotor shaft. The inner and the outer rotor shafts are separated by a gap filled with working medium gas. The working medium gas provides cooling for the rotor shafts, but is warmer than the temperature inside the bearing compartment. An intershaft seal prevents the working medium gas from leaking into the oil compartment and prevents the oil from leaking out of the compartment. The intershaft seal traditionally employs two face seals, to seal to the shafts, and a ring seal therebetween, to limit leakage between the face seals.
SUMMARY
According to an embodiment disclosed herein, a seal assembly for separating a relatively high pressure area from a relatively low pressure area includes a first seal carrier having a circumferential body, the first seal carrier having a first land thereon; and, a seal having a circumferential body located within the first seal carrier, the seal having a first surface for sealing against the first land and a second surface and wherein one of the first surface or the first land has an unmachined wear coating that resists fretting and vibration.
According to any previous claim made herein, the seal does not contact the first seal carrier but for contact of the first surface with the first land.
According to any previous claim made herein, the coating is electroless nickel.
According to any previous claim made herein, the first surface has an unmachined wear coating that resists fretting and vibration.
According to any previous claim made herein, the first land has an unmachined wear coating that resists fretting and vibration.
According to any previous claim made herein, a second seal carrier has a circumferential body that moves relative to the first seal carrier the second seal carrier having a second land upon which the second surface is disposed thereupon.
According to any previous claim made herein, the second seal carrier extends around the first seal carrier.
According to any previous claim made herein, the second surface may move across the second land when forced by a pressure differential between the high pressure area and the low pressure area.
According to any previous claim made herein, the second surface has an unmachined wear coating that resists fretting and vibration.
According to any previous claim made herein, the second land has an unmachined wear coating that resists fretting and vibration.
According to a further non-limiting embodiment disclosed herein, a seal for separating a relatively high pressure area from a relatively low pressure area includes a seal having a circumferential body, the seal having a first surface for sealing against a land and a second surface wherein the first surface has an unmachined wear coating that resists fretting and vibration.
According to any previous claim made herein, the coating is electroless nickel.
According to any previous claim made herein, the second surface has an unmachined wear coating that resists fretting and vibration.
According to any previous claim made herein, further including a seal carrier having a land thereon for cooperating with the first surface.
According to any previous claim made herein, the seal carrier houses the seal but does not touch it but for contact between the land and the first surface.
According to any previous claim made herein, the first surface is radially aligned.
According to any previous claim made herein, the first surface the second surface are perpendicular to each other.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features and advantages of the disclosed examples will become apparent to those skilled in the art from the detailed description. The figures that accompany the detailed description can be briefly described as follows:
FIG. 1 shows a gas turbine engine in which an embodiment of an invention is shown.
FIG. 2 shows an embodiment of a coated seal for use in a bearing compartment shown in FIG. 1 .
FIG. 3 shows an embodiment of a coated seal taken along the lines 3 - 3 of FIG. 2 .
DETAILED DESCRIPTION
FIG. 1 schematically illustrates a gas turbine engine 20 . The gas turbine engine 20 is disclosed herein as a two-spool turbofan that generally incorporates a fan section 22 , a compressor section 24 , a combustor section 26 and a turbine section 28 . Alternative engines might include an augmentor section (not shown) among other systems or features. The fan section 22 drives air along a bypass flowpath B while the compressor section 24 drives air along a core flowpath C for compression and communication into the combustor section 26 then expansion through the turbine section 28 . Although depicted as a turbofan gas turbine engine in the disclosed non-limiting embodiment, it should be understood that the concepts described herein are not limited to use with turbofans as the teachings may be applied to other types of turbine engines including three (or more) spooled architectures.
The engine 20 generally includes a low speed spool 30 and a high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38 . It should be understood that various bearing systems 38 at various locations may alternatively or additionally be provided.
The low speed spool 30 generally includes an inner shaft 40 that interconnects a fan 42 , a low pressure (or first) compressor section 44 and a low pressure (or first) turbine section 46 . The inner shaft 40 is connected to the fan 42 through a geared architecture 48 to drive the fan 42 at a lower speed than the low speed spool 30 . The geared architecture comprises a gear assembly 60 enclosed within a gear housing 62 . The gear assembly 60 couples the inner shaft 40 to a rotating fan structure. The high speed spool 32 includes an outer shaft 50 that interconnects a high pressure (or second) compressor section 52 and high pressure (or second) turbine section 54 . A combustor 56 is arranged between the high pressure compressor 52 and the high pressure turbine 54 . A mid-turbine frame 57 of the engine static structure 36 is arranged generally between the high pressure turbine 54 and the low pressure turbine 46 . The mid-turbine frame 57 supports one or more bearing systems 38 in the turbine section 28 . The inner shaft 40 and the outer shaft 50 are concentric and rotate via bearing systems 38 about the engine central longitudinal axis A, which is collinear with their longitudinal axes. As used herein, a “high pressure” compressor or turbine experiences a higher pressure than a corresponding “low pressure” compressor or turbine.
The core airflow C is compressed by the low pressure compressor 44 then the high pressure compressor 52 , mixed and burned with fuel in the combustor 56 , then expanded over the high pressure turbine 54 and low pressure turbine 46 . The mid-turbine frame 57 includes airfoils 59 which are in the core airflow path. The turbines 46 , 54 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the expansion.
The engine 20 in one example is a high-bypass geared aircraft engine. In a further example, the engine 20 bypass ratio is greater than about six (6), with an example embodiment being greater than ten (10), the geared architecture 48 is an epicyclic gear train, such as a star gear system (sun gear in meshing engagement with a plurality of star gears supported by a carrier and in meshing engagement with a ring gear) or other gear system, with a gear reduction ratio of greater than about 2.3 and the low pressure turbine 46 has a pressure ratio that is greater than about 5. In one disclosed embodiment, the engine 20 bypass ratio is greater than about ten (10:1), the fan diameter is significantly larger than that of the low pressure compressor 44 , and the low pressure turbine 46 has a pressure ratio that is greater than about 5:1. Low pressure turbine 46 pressure ratio is pressure measured prior to inlet of low pressure turbine 46 as related to the pressure at the outlet of the low pressure turbine 46 prior to an exhaust nozzle. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines including direct drive turbofans.
Referring now to FIG. 2 , a bearing compartment 65 having a given static pressure (e.g., a low pressure) therein is adjacent the side 70 of the gas turbine engine 20 having a second static pressure (e.g., a high pressure) greater than the given pressure (e.g., the low pressure). Oil 75 is disposed within the bearing compartment 65 .
A seal assembly 80 separates the high pressure side 70 from the low pressure bearing compartment 65 . The seal assembly 80 comprises a forward seal carrier 85 which may be circumferential, an aft circumferential seal carrier 90 , a forward land 95 cooperating with the forward seal carrier 85 and an aft land 100 cooperating with the aft seal carrier 90 . The forward seal carrier 85 has circumferential body 105 , an L-shaped radially outwardly extending seal holder 110 extending from a forward end 115 of the forward seal carrier 85 . A forward seal 120 is disposed within the L-shaped radially inwardly extending seal holder 110 . A U-shaped seal holder 125 extends from an aft end 130 of the circumferential body 105 . A piston ring 135 is disposed within the U-shaped seal holder 125 as will be discussed infra.
The aft seal carrier 90 includes a circumferential body 140 , an L-shaped radially outwardly extending seal holder 145 extending from an aft end 147 thereof. A seal 149 fits within the L-shaped radially inwardly extending seal holder 145 to engage the land 100 . The seal also has a sealing land (or surface) 150 which engages the land 100 . The seals 149 and 120 are typically carbon made of carbon but other materials may be used. The aft seal carrier 90 may act as a piston and move axially relative to the forward seal carrier 85
Referring now to FIG. 3 , the seal holder 125 , which may be U-shaped, holds a radial inner area of body 155 of the piston ring 135 . The body 155 has a radial inner profile 160 that does not touch the seal holder 125 . The piston ring 135 has an axially forward face 170 for cooperating with the radially outer wall 175 of the seal holder 125 that is parallel to, but not in plane with a radially inner wall 180 of the seal holder 125 . The body 155 has a radially outward surface 185 engaging land 150 on the aft carbon carrier.
The body of the piston ring 135 has an axially aft extending portion 189 that prevents the piston ring from being inserted in the seal holder 125 in a backwards position. Such installation is not possible because if there is contact between the aft extending portion 189 and the radially outer wall 175 , the body 155 will not fit in seal holder 125 .
During operation, as the pressure of flow C increases on the high pressure side 70 , and the pressure urges the piston ring 135 axially forward across the land 150 so the axially forward face 170 engages the radially outer wall 175 of the seal holder 125 to effectuate a seal therebetween. The relative pressure also tends to force the piston ring 135 radially outer face 185 against the land 150 .
This piston ring 135 is usually made of carbon. However, the Inventors have discovered that the piston ring 135 is subject to fret wear and vibratory wear as the upstream and downstream carbon carriers 80 and 90 move relative to each other. Where the piston ring 135 is subject to rubbing and chafing caused by “fretting” along with regular vibratory modes caused by vibratory modes that are normally experienced in rotating machinery premature failure of a sealing function may occur.
As a result, the applicants have coated the radially outer wall 175 and the radially outer face 185 of the piston ring with electroless nickel 190 that can withstand the fret and vibratory wear experienced by the piston ring. A electroless plating process is followed by using a reducing agent such as sodium hypophosphite to produce a negative charge on the piston ring 135 that draws nickel ions in solution thereto to coat the part. The piston ring 135 may be masked to coat only the desired portions thereof like the axial forward face 170 .
One of the advantages of electroless nickel is that it does not require machining and other coatings that are known to resist fretting and vibratory modes that do not require machining (e.g., “unmachined”) may be used herein. Furthermore, instead of coating the axial forward face 170 and radially outer face 185 of the piston ring 135 , one may choose to coat the radially outer wall 175 or the land of the forward seal carrier 85 or the land 150 of the axially aft seal carrier 90 . The surfaces subject to the fretting and vibratory forces (e.g., axial forward face 170 , radially outer face 185 , or the radially outer wall 175 or the land 150 ) may be the only ones coated.
The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. Thus, the scope of legal protection given to this disclosure can only be determined by studying the following claims. | A seal assembly for separating a relatively high pressure area from a relatively low pressure area includes a first seal carrier having a circumferential body that has a land thereon and a seal. The seal has a circumferential body located within the first seal carrier, the seal having a first surface for sealing against the first land and a second surface and wherein one of the first surface or the first land has an unmachined wear coating that resists fretting and vibration. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of co-pending U.S. patent application Ser. No. 12/802,532, filed, Dec. 29, 2010, entitled, “Operating Point Management In Multi-Core Architectures”, which is a continuation of U.S. patent application Ser. No. 12/401,538, filed Mar. 10, 2009, entitled “Method And Apparatus To Control Power Consumption Of A Plurality Of Processor Cores”, now U.S. Pat. No. 8,650,424, Issued on Feb. 11, 2014, which is a continuation of U.S. patent application Ser. No. 11/026,705, filed Dec. 30, 2004, entitled, “Method, System, And Apparatus For Selecting A Maximum Operation Point Based On Number Of Active Cores And Performance Level Of Each Of The Active Cores”, now U.S. Pat. No. 7,502,948, Issued on Mar. 10, 2009, all of which are herein incorporated by reference.
TECHNICAL FIELD
One or more embodiments of the present invention generally relate to operating point management. In particular, certain embodiments relate to managing operating points in multi-core processing architectures.
DISCUSSION
The popularity of computing systems continues to grow and the demand for more complex processing architectures has experienced historical escalations. For example, multi-core processors are becoming more prevalent in the computing industry and are likely to be used in servers, desktop personal computers (PCs), notebook PCs, personal digital assistants (PDAs), wireless “smart” phones, and so on. As the number of processor cores in a system increases, the potential maximum power also increases. Increased power consumption translates into more heat, which poses a number of difficulties for computer designers and manufacturers. For example, device speed and long term reliability can deteriorate as temperature increases. If temperatures reach critically high levels, the heat can cause malfunction, degradations in lifetime or even permanent damage to parts.
While a number of cooling solutions have been developed, a gap continues to grow between the potential heat and the cooling capabilities of modern computing systems. In an effort to narrow this gap, some approaches to power management in computer processors involve the use of one or more on-die temperature sensors in conjunction with a power reduction mechanism. The power reduction mechanism is typically turned on and off (e.g., “throttled”) according to the corresponding temperature sensor's state in order to reduce power consumption. Other approaches involve alternatively switching between low and high frequency/voltage operating points.
While these solutions have been acceptable under certain circumstances, there remains considerable room for improvement. For example, these solutions tend to make the system performance more difficult to determine (i.e., the solutions tend to be “non-deterministic”). In fact, temperature based throttling is often highly dependent upon ambient conditions, which can lower the level of performance predictability. For example, on a warm day, more throttling (and therefore lower performance) is likely to occur than on a cool day for the same usage model. In addition, reducing power by throttling between operating points can add to the inconsistency of the user's experience. These drawbacks may be magnified when the gap between the dissipated power and the external cooling capabilities increases due to the presence of multiple processor cores in the system.
BRIEF DESCRIPTION OF THE DRAWINGS
The various advantages of the embodiments of the present invention will become apparent to one skilled in the art by reading the following specification and appended claims, and by referencing the following drawings, in which:
FIG. 1 is a diagram of an example of a processing architecture according to one embodiment of the invention;
FIG. 2 is a diagram of an example of a system according to one embodiment of the invention;
FIG. 3 is a flowchart of an example of a method of managing operating points according to one embodiment of the invention;
FIG. 4 is a flowchart of an example of a process of determining a number of active cores according to one embodiment of the invention; and
FIG. 5 is a flowchart of an example of a process of selecting a maximum operating point according to one embodiment of the invention.
DETAILED DESCRIPTION
In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present invention. It will be evident, however, to one skilled in the art that the embodiments of the present invention may be practiced without these specific details. In other instances, specific apparatus structures and methods have not been described so as not to obscure the embodiments of the present invention. The following description and drawings are illustrative of the embodiments of the invention and are not to be construed as limiting the embodiments of the invention.
FIG. 1 shows a processing architecture 10 having a plurality of processor cores 12 ( 12 a, 12 b ), an activity module 14 and a plurality of maximum operating points 16 ( 16 a, 16 b ) from which to select. The processor cores 12 can be similar to a Pentium® 4 processor core available from Intel® Corporation in Santa Clara, Calif., where each core 12 may be fully functional with instruction fetch units, instruction decoders, level one (L 1 ) cache, execution units, and so on (not shown). In addition, the activity module 14 may be implemented in fixed functionality hardware such as complementary metal oxide semiconductor (CMOS) technology, in microcode, in software (e.g., as part of an operating system/OS), or any combination thereof. In the illustrated example, the activity module 14 is implemented in hardware.
In one example, each of the maximum operating points 16 includes a maximum operating frequency and voltage. The maximum operating points 16 can be determined based on knowledge of the cooling solutions available to the system and/or the thermal constraints of the system. For example, it may be determined that in a dual core architecture with only one core active, the system can be properly cooled if the active core is limited to a maximum operating frequency of 2.0 GHz (and/or a core voltage of 1.7 V). It may also be known, however, that if both cores are active, the cores should be limited to a maximum operating frequency of 1.5 GHz (and/or a core voltage of 1.35 V) in order for the cooling solution to be effective. The illustrated activity module 14 determines the number 18 of active cores in the plurality of processor cores 12 and selects a maximum operating point 17 for the active cores based on the number 18 of active cores. The maximum operating points 16 could be stored in a configuration table.
For example, the activity module 14 might make use of a configuration table such as the following Table I, to select a maximum operating point in a dual core architecture.
TABLE 1 # Active Max Freq. 1 2.0 GHz 2 1.5 GHz
Where the first maximum operating point 16 a is assigned the value of 2.0 GHz and the second maximum operating point 16 b is assigned the value of 1.5 GHz. Thus, if the activity module 14 determines that the first core 12 a is active and the second core 12 b is inactive, the number of active cores would be one and the first maximum operating point 16 a (i.e., a maximum operating frequency of 2.0 GHz) would be selected for the first core 12 a. Similarly, if it is determined that the first core 12 a is inactive and the second core 12 b is active, the first maximum operating point 16 a (i.e., a maximum operating frequency of 2.0 GHz) would be selected for the second core 12 b.
If, on the other hand, the activity module 14 determines that both the first core 12 a and the second core 12 b are active, the number of active cores would be two and the second maximum operating point 16 b (i.e., a maximum operating frequency of 1 . 5 GHz) would be selected for both the first core 12 a and the second core 12 b. Thus, under the above scenario, the illustrated activity module 14 could determine that both cores 12 a, 12 b are active and therefore set the second maximum operating point 16 b as the selected maximum operating point 17 . Specific frequencies are given to facilitate discussion only.
By selecting the maximum operating point 17 based on the number 18 of active cores, the architecture 10 provides a number of advantages over conventional techniques. For example, the gap between the potential maximum power and the available cooling capabilities can be narrowed in a fashion that is not directly dependent upon temperature. Because the dependency on ambient temperature conditions can be minimized, more predictable performance can result. The approaches described herein are more deterministic than conventional approaches. In addition, limiting the operating point based on the number of active cores increases the effectiveness of the available cooling solutions.
The maximum operating point 17 may also be selected based on active core performance levels 19 , which can be determined by the activity module 14 . In particular, the processor cores 12 may be able to operate at different performance levels based on a variety of factors. For example, one approach may involve switching between low and high frequency/voltage operating points based on core utilization and/or temperature. In any case, it may be determined that an active core is running at a relatively low performance level, which may allow the other core(s) to operate at a higher performance level than would be permitted under a pure active/idle determination.
For example, it may be determined that cores 12 a and 12 b are active and that the first core 12 a is operating at 1.0 GHz. It may also be determined that under such a condition, the second core 12 b could operate at a frequency as high as 1 . 86 GHz without exceeding the cooling capability of the system. Rather than selecting the maximum operating point 17 for both cores to be 1.5 GHz, the activity module 14 could use the active core performance levels 19 to set a first core maximum operating point of 1.0 GHz and a second core maximum operating point of 1.86 GHz. Thus, the selected maximum operating point 17 could have a per-core component.
Turning now to FIG. 2 , a system 20 having a multi-core processor 22 is shown, where the system 20 may be part of a server, desktop personal computer (PC), notebook PC, handheld computing device, etc. In the illustrated example, the processor 22 has an activity module 14 ′, a plurality of processor cores 12 ′ ( 12 a ′- 12 n ′) and a voltage and frequency controller 24 .
The illustrated system 20 also includes one or more input/output ( 1 / 0 ) devices 26 and various memory subsystems coupled to the processor 22 either directly or by way of a chipset 28 . In the illustrated example, the memory subsystems include a random access memory (RAM) 30 and 31 such as a fast page mode (FPM), error correcting code (ECC), extended data output (EDO) or synchronous dynamic RAM (SDRAM) type of memory, and may also be incorporated in to a single inline memory module (SIMM), dual inline memory module (DIMM), small outline DIMM (SODIMM), and so on. For example, SODIMMs have a reduced packaging height due to a slanted arrangement with respect to the adjacent circuit board. Thus, configuring the RAM 30 as a SODIMM might be particularly useful if the system 20 is part of a notebook PC in which thermal constraints are relatively tight. SODIMMs are described in greater detail in U.S. Pat. No. 5,227,664 to Toshio, et al.
The memory subsystems may also include a read only memory (ROM) 32 such as a compact disk ROM (CD-ROM), magnetic disk, flash memory, etc. The illustrated RAM 30 , 31 and ROM 32 include instructions 34 that may be executed by the processor 22 as one or more threads. The ROM 32 may be a basic input/output system (BIOS) flash memory. Each of the RAM 30 , 31 and/or ROM 32 are able to store a configuration table 36 that can be used to select maximum operating points. The table 36 , which may be calculated “on the fly” by software or pre-stored in memory, can be similar to the Table I discussed above. In this regard, the activity module 14 ′ may include a configuration table input 38 to be used in accessing the configuration table 36 .
As already discussed, the activity module 14 ′ is able to determine the number of active cores in the plurality of processor cores 12 ′. The activity can be determined by monitoring a state signal 40 ( 40 a - 40 n ) of each of the plurality of processor cores 12 ′ and identifying whether each state signal 40 indicates that the corresponding core is active. For example, the activity module 14 ′ could monitor an Advanced Configuration and Power Interface (e.g., ACPI Specification, Rev. 3.0, Sep. 2, 2004; Rev. 2.0c, Aug. 25, 2003; Rev. 2.0, Jul. 27, 2000, etc.) processor power state (“Cx state”) signal of each of the plurality of processor cores 12 ′. ACPI Cx states are relatively unproblematic to monitor and therefore provide a useful solution to determining the number of active cores.
ACPI defines the power state of system processors while in the working state (“GO”) as being either active (executing) or sleeping (not executing), where the power states can be applied to each processor core 12 ′. In particular, processor power states are designated as C 0 , C 1 , C 2 , C 3 , . . . Cn. The shallowest, C 0 , power state is an active power state where the CPU executes instructions. The C 1 through Cn power states are processor sleeping states where the processor consumes less power and dissipates less heat than leaving the processor in the C 0 state. While in a sleeping state, the processor core does not execute any instructions. Each processor sleeping state has a latency associated with entering and exiting the state that corresponds to the state's power savings. In general, the longer the entry/exit latency, the greater the power savings when in the state. To conserve power, an operating system power management (OSPM) module (not shown) places the processor core into one of its supported sleeping states when idle.
The state signals 40 can also include information regarding performance levels. For example, the state signals 40 may indicate the performance level of each active core. Such a signal could be provided by ACPI performance state (Px state) signals. In particular, while in the C 0 state, ACPI can allow the performance of the processor core to be altered through a defined “throttling” process and through transitions into multiple performance states (Px states). While a core is in the P 0 state, it uses its maximum performance capability and may consume maximum power. While a core is in the P 1 state, the performance capability of the core is limited below its maximum and consumes less than maximum power. While a core is in the Pn state, the performance capability of core is at its minimum level and consumes minimal power while remaining in an active state. State n is a maximum number and is processor or device dependent. Processor cores and devices may define support for an arbitrary number of performance states not to exceed 16 according to the ACPI Specification, Rev. 3.0.
Thus, if the illustrated activity module 14 ′ monitors sleep state signals 40 , it can identify whether each sleep state signal 40 indicates that the corresponding core is active. The activity module 14 ′ can then search the configuration table 36 for an entry containing the number of active cores. A similar search could be conducted with respect to performance levels. Upon finding the entry, the activity module 14 ′ may retrieve a maximum operating point, via the configuration table input 38 , from the entry, where the maximum operating point enables a parameter such as frequency or core voltage to be limited.
For example, the activity module 14 ′ can generate a limit request 42 based on the maximum operating point. As already noted, the limit request 42 may specify a maximum operating frequency and/or maximum core voltage. Thus, as the active cores submit operating point requests to the controller 24 , the controller 24 ensures that none of the operating points exceed the maximum operating point specified in the limit request 42 . Simply put, the controller 24 can limit the appropriate parameter of the active cores based on the limit request 42 .
Although the illustrated system 20 includes a processing architecture that contains a single package/socket, multi-core processor 22 , the embodiments of the invention are not so limited. For example, a first subset of the plurality of processor cores 12 could be contained within a first processor package and a second subset of the plurality of processor cores 12 could be contained within a second processor package. Indeed, any processing architecture in which performance predictability and/or power management are issues of concern can benefit from the principles described herein. Notwithstanding, there are a number of aspects of single package/socket, multi-core processors for which the system 20 is well suited.
Turning now to FIG. 3 , a method 44 of managing operating points is shown. The method 44 may be implemented in fixed functionality hardware such as complementary metal oxide semiconductor (CMOS) technology, microcode, software such as part of an operating system (OS), or any combination thereof. Processing block 46 provides for determining the number of active cores in a plurality of processor cores and/or the performance level of each of the active cores. A maximum operating point is selected for the active cores at block 48 based on the number of active cores and/or the active core performance level(s). Block 50 provides for generating a limit request based on the maximum operating point, where an operating parameter of the cores can be limited based on the limit request. The limit request may specify a maximum operating frequency and/or maximum operating voltage.
FIG. 4 shows one approach to determining the number of active cores in greater detail at block 46 ′. In particular, the illustrated block 52 provides for monitoring a sleep state signal of each of the plurality of processor cores. As already discussed, the sleep state signals may be ACPI Cx state signals. If the monitoring at block 52 is to include monitoring performance state data, the signals may be ACPI Px state signals. Block 54 provides for identifying whether each sleep state signal indicates that a corresponding core is active.
Turning now to FIG. 5 , one approach to selecting a maximum operating point is shown in greater detail at block 48 ′. In the example shown, the maximum operating point is selected based on the number of active cores. Alternatively, the selection could be based on the performance level of each active core. In particular, the illustrated block 56 provides for searching a configuration table for an entry containing the number of active cores. In one embodiment, the searching is conducted on a BIOS configuration table. The maximum operating point is retrieved from the entry at block 58 . Alternatively, the maximum operating points could be calculated. Such an approach may be particularly useful if the selection of maximum operating points is based on active core performance levels. For example, the calculation could involve an averaging (weighted or unweighted) of core operating frequencies. A weighted average may be particularly useful in systems having non-symmetrical cores (i.e., large and small cores in the same system) because the larger cores could be given a greater weight due to their potentially greater contribution to the overall power consumption.
Thus, the embodiments described herein can provide for the constraining of power in multi-core processing architectures while providing predictable performance throughout most of the architecture's power range. By dynamically adjusting the maximum frequency and voltage operating point to the number of active cores in the architecture, these solutions offer a coarse-grained mechanism that can be used as a stand-alone technique or as a complement to traditional temperature-based throttling techniques.
Those skilled in the art can appreciate from the foregoing description that the broad techniques of the embodiments of the present invention can be implemented in a variety of forms. Therefore, while the embodiments of this invention have been described in connection with particular examples thereof, the true scope of the embodiments of the invention should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, specification, and following claims. | For one disclosed embodiment, a processor comprises a plurality of processor cores to operate at variable performance levels. One of the plurality of processor cores may operate at one time at a performance level different than a performance level at which another one of the plurality of processor cores may operate at the one time. The plurality of processor cores are in a same package. Logic of the processor is to set one or more operating parameters for one or more of the plurality of processor cores. Logic of the processor is to monitor activity of one or more of the plurality of processor cores. Logic of the processor is to constrain power of one or more of the plurality of processor cores based at least in part on the monitored activity. The logic to constrain power is to limit a frequency at which one or more of the plurality of processor cores may be set. Other embodiments are also disclosed. | 8 |
FIELD OF THE INVENTION
[0001] The invention is generally in the field of biosensors, and concerns a sensor useful for the determination of the presence, and optionally also concentration, of an analyte in a liquid, particularly aqueous, medium. The present invention relates to such electrodes, as well as their use and systems comprising them.
PRIOR ART
[0002] In the following description, reference will be made to several prior art documents shown in the list of references below. The reference will be made by indicating their number from this list.
[0003] References
[0004] 1. E. Engvall, in: Methods in Enzymology , Vol. 70, 1980, pp. 419-439.
[0005] 2. A. Shons, F. Dorman, J. Najarian, J. Biomed. Mater. Res. 6, 565 (1972).
[0006] 3. A. A. Suleiman and G. G. Guilbault, Analyst , 119, 2279 (1994).
[0007] 4. M. D. Ward and D. A. Buttry, Science, 249, 1000 (1990).
[0008] 5. J. R. Oliveria and S. F. Silver, U.S. Pat. No. 4,242,096 (1980).
[0009] 6. T. K. Rice, U.S. Pat. No. 4,236,893 (1980).
[0010] 7. T. K. Rice, U.S. Pat. No. 4,314,821 (1982).
[0011] 8. J. E. Roederer, G. J. Bastiaans, Anal. Chem., 55, 2333 (1983).
[0012] 9. J. E. Roederer and G. J. Bastiaans, U.S. Pat. No. 4,735,906 (1988).
[0013] 10. H. Muramatsu, J. M. Dicks, E. Tamiya and I. Karube, Anal. Chem., 59, 2760 (1987).
[0014] 11. D. Mueller-Schulte and H. Laurs, CA. 1990, 112(7), 51807 g.
[0015] 12. H. Muramatsu, K. Kajiwara, E. Tamiya and I. Karube, Anal. Chim. Acta, 188, 257 (1986).
[0016] 13. H. Muramatsu, Y., Watanabe, M. Hikuma, T. Ataka, I. Kubo, E. Tamiya and I. Karube, Anal. Lett., 22, 2155 (1989).
[0017] 14. B. Konig and M. Grätzel, Anal. Lett., 26, 1567 (193).
[0018] 15. M D. Ward and R. C. Ebersole, PCT Application, Application No. WO 89/09937.
[0019] 16. R. C. Ebersole, R. P. Foss and M. D. Ward, PCT Application, Application No. WO/94/02852.
[0020] 17. R. C. Ebersole and J. R. Moran, PCT Application, Application No. WO/91/05251.
[0021] 18. N. J. Geddes, E. M. Paschinger, D. N. Furlong, F. Caruso, C. L. Foffmann and J. F. Rabolt, Thin Solid Films, 260:192-199 (1995).
[0022] 19. I. Willner, S. Rubin and Y. Cohen, J. Amer. Chem. Soc., 115:4937-4938, (1993).
[0023] 20. I. Willner, R. Blonder and A. Dagan, J. Amer. Chem. Soc., 116:9365-9366, (1994).
[0024] Mention of the above references in this writing does not mean to imply that these references are in any way relevant to the issue of patentability of the invention as defined in the appended claims.
BACKGROUND OF THE INVENTION
[0025] The specificity of antigen-antibody binding interactions and the technological progress in eliciting monoclonal antibodies for low molecular weight materials provide the grounds to design sensitive immunosensor devices for clinical diagnostics, food control and environmentally polluting substances. The most extensively developed immunosensor analyses include radioisotopic antigen/Ab labels and enzyme-linked immunosorbant assays (ELISA) (1) .
[0026] The discovery of a linear relationship between the change in the oscillating frequency of a piezoelectric crystal and the mass variation on the crystal as a result of binding or adsorption phenomena opened the possibilities to monitor gravimetrically antigen-antibody binding phenomena. The mathematical relation between the frequency changes of a piezoelectric crystal, Δf, and mass changes, Δm, on the crystal is given by the following Sauerbrey equation:
Δ f =−2.3×10 6 f o 2 ·Δm/A
[0027] where f o is the fundamental resonance frequency of the crystal prior to the mass variation and A is the surface area of deposited mass. For example, for a crystal exhibiting a fundamental frequency of 9 MHz and surface area of 1 cm 2 , a mass-change on the crystal that corresponds to 1×10 −9 g will stimulate a frequency change, Δf, of 6 Hz.
[0028] The first analytical use of piezoelectric crystals in relation to antigen-antibody (Ag—Ab) interactions was reported in 1972 (2) , where a nyebar precoated crystal was further coated via hydrophobic interactions, with bovine serum albumin (BSA) and the association of the BSA—Ab to the crystal was monitored by the frequency changes. Since then, the piezoelectric detection of antigens and antibodies by piezoelectric means or the quartz crystal microbalance (QCM) has been adopted in a series of analytical studies. The progress in this area has been reviewed by Suleiman et al., 1994 (3) and Ward et al., 1990 (4) . Immobilization of an antibody on a QCM device has been described by Geddes et al. (18) .
[0029] Several patents describe the application of QCM for the analysis of antigens and antibodies. Physical adsorption of antigens to a crystal was used as a means for the detection of antigens by interacting the crystal with a mixture of the analyte antigen and a predetermined amount of Ab (5) . The decrease in the antigen concentration was inversely related to the antigen concentration in the sample. In two patents by Rice (6,7) , methods for the determination of Abs by QCM were disclosed. The antigen was immobilized on a polymer precoated crystal and the frequency changes as a result of Ab association related to the analyte Ab concentration in the sample. By this method, human IgG against honey bee venom, phospholipase A, and keyhole limpet hemocyanine were analyzed (6) . However, non-specific binding to the crystal interfered with the analyses. In a follow-up patent (7) , the detection of low molecular weight components by a pre-coated crystal with the anti-Ab and competitive binding assay of the Ab-low molecular weight analyte was described. All of these analyses were performed by treatment of the crystals in solution and subsequent frequency measurements in air. This two-step solution/gas procedure allows improvement of the sensitivity of the resonating QCM, but introduces technical complications and the interference of hydration/dehydration phenomena that are reflected in the frequency parameters. Ward et al. (15) and Ebersole et al. (17) disclose a QCM assay where the sensitivity is increased by the use of an enzyme comprising conjugates which binds to the analyte after the latter has been bound to a capturing agent, which enzyme catalyzes a reaction where a substrate is converted to the product and the product which is absorbed on the QCM increases the mass of the QCM which gives rise to a change in its resonance frequency. Ebersole et al. (16) discloses a method that makes use of a polymer which changes its mass in the presence of an analyte, e.g. H + ions (serving as a pH) sensor.
[0030] Piezoelectric immunoassaying in the liquid phase has important technical advantages as it allows stationary and flow analysis of aqueous samples. The method suffers, however, from a basic physical limitation due to substantially lower frequency changes of the crystal as a result of the solution viscosity. QCM immunoassays in solution were reported by Roederer (8) and addressed in a follow-up patent (9) . The quartz crystal was modified with glycidoxypropyltrimethoxy silane (GOPS), and the surface-modified crystal was then further modified by anti-human IgG antibody and then applied for the piezoelectric detection of human IgG. The detection limit of the device was determined to be 13 μg·ml −1 . A closely related approach was adopted by Muramatsu et al. (10) where the quartz crystals were surface-modified by γ-aminopropyl triethoxy silane and further derivatized by protein A. The surface-modified crystals were then applied for the determination of human IgG in the concentration range 10 −6 -10 −2 mg·ml −1 . A related patent disclosed the piezoelectric analysis of thyroxine using a polyamide 6 polymer coating and anti-thyroxine Ab as sensing interface (11) .
[0031] Piezoelectric analysis of high molecular weight antigens such as microbial cells was addressed using antibody-coated quartz crystals. C. albicans cells in the concentration range 1×10 6 -5×10 8 cells·ml −1 were analyzed by an anti- Candida albicans Ab surface (12), E. coli with an anti- E. coli interface (13) and protein A-coated crystals acted as piezoelectric sensing interface for various bacteria including Salmonella, Shigella, Yersinia and E. Coli (14) .
[0032] Use of photoisomerizable substance for the photoregulated binding of molecules to a substrate has been described by Willner et al. (19) The aplication of this feature in reversible amperometric immunosensors has been described by Willner et al. (20)
[0033] Methods utilizing piezoelectric devices allow immuno-chemical sensing of interactions between two members of a recognition pair such as Ab—Ag, sugar-lectin, biotin-avidin, etc., without the need for labeling, and provide competitive analytical tools to conventional radio-labeled and enzyme-labeled analyses.
GENERAL DESCRIPTION OF THE INVENTION
[0034] It is an object of the present invention to provide a method for determining the presence and optionally the concentration of analyte in a liquid medium, analyte being a member of a recognition pair.
[0035] It is further an object, in accordance with an embodiment of the present invention, to provide a system for carrying out the above method.
[0036] It is furthermore an object of the present invention to provide electrodes for use in the above system and method.
[0037] It is still further an object of the present invention to provide a process for the preparation of such electrodes.
[0038] The present invention makes use of a piezoelectric crystal and determining a change in mass bound to the crystal by measuring a change of its resonance frequency. In the following, the term “Δf response” will be used to denote a change of frequency of the electrode as the result of binding of a mass thereto or release of a mass therefrom.
[0039] In accordance with the present invention, a novel system and an electrode for use in the system are provided. The system in accordance with the present invention is capable, by means of a Δf response, to determine the presence and optionally the concentration of an analyte in a liquid medium. The analyte is a member of a pair of molecules or complexes of molecules, which can specifically bind to one another in a non-covalent manner. Such a pair of molecules will be referred to herein as “recognition pair”. The recognition pair may consist for example of antigen-antibody, ligand-receptor, sugar-lectin, biotin-avidin, enzyme-substrate, oligonucleotide-oligonucleotide with a complementary sequence, oligonucleotide-protein, olignucleotide-cell, etc.
[0040] In the following description the terms “determination” or “determine” will be used to denote both qualitative and quantitative determination of binding. Where, for example, the method and system defined below are used for determining an analyte in a liquid medium, this is meant to denote determining the presence of an analyte in the medium and optionally its concentration. In other words, a Δf response will be used as a qualitative measure for the presence of the analyte in a medium; the extent of the Δf response will be used as a measure of the amount of analyte in a tested medium.
[0041] The term “analyte” already used above and which will be used further below, is meant to denote an unknown agent determined in a liquid medium.
[0042] The present invention has several aspects. One such aspect concerns a system for determining binding between two members of a recognition pair (“system aspect”); another such aspect relates to a method for determining such binding, which may be used for testing an analyte in a medium (“method aspect”); a further aspect is concerned with probes for use in the above system and method (“probe aspect”); and a further aspect is concerned with a process for the preparation of such a probe (“process aspect”).
[0043] In accordance with the system aspect of the present invention, there is provided a system for determining binding between two members of a recognition pair, comprising:
[0044] (a) a probe comprising a piezoelectric crystal, electrodes on two opposite faces of the crystal, and one or more metal plates carried on the surface of said crystal, said metal plates being the same or different than said electrodes, the metal plates having immobilized thereon a first member of a recognition pair, binding of a second member of the recognition pair to the first member, or dissociation between the two members and release of the second member from the probe, causing a change of mass resulting in a change to the probe's resonance frequency;
[0045] (b) a vessel for holding a liquid, the probe being immersed in the liquid to allow either
[0046] binding between the first, immobilized member and the second member dissolved in the liquid, or
[0047] release of the second member, a priori bound to said first member, into said liquid; and
[0048] (c) electric or electronic circuitry for generating an alternating electric field between said electrodes, and measuring of the resonance frequency of said crystal.
[0049] In accordance with an embodiment of the method aspect of the invention, there is provided a method for determining binding between a first member of a recognition pair and a second member of a recognition pair, the second member being a priori contained in a liquid medium, comprising:
[0050] (a) providing a probe comprising a piezoelectric crystal, electrodes on two opposite faces of the crystal, and comprising one or more metal plates carried on the surface of said crystal, said plates being the same or different than said electrodes, the first member of the recognition pair being immobilized on the said plates;
[0051] (b) measuring an initial resonance frequency of the probe;
[0052] (c) contacting said probe with a liquid medium containing said second member for a time sufficient to allow binding between the two members; and
[0053] (d) measuring a second resonance frequency, a lower second resonance frequency as compared to the initial resonance frequency indicating the presence of said second member in the liquid medium.
[0054] In accordance with another embodiment of the method aspect, there is provided a method for determining an analyte in a liquid medium, comprising:
[0055] (a) providing a probe comprising a piezoelectric crystal, electrodes on two opposite faces of the probe, and comprising one or more metal plates carried on the surface of said crystal, said metal plates being the same or different than said electrodes, the metal plates having immobilized thereon a first member of a recognition pair, the second member of said pair being non-covalently bound to said first member, said second member being capable of binding to said analyte, the binding between said second member and said analyte being competitive to the binding of said second member to said immobilized member;
[0056] (b) measuring an initial resonance frequency of the probe;
[0057] (c) contacting said probe with said liquid medium under conditions and for a time such that in the presence of said analyte, at least some of said second member will be released from the electrode and bind to said analyte; and
[0058] (d) measuring a second resonance frequency, a higher second resonance frequency as compared to the initial resonance frequency indicating the presence of said analyte in said medium.
[0059] In accordance with a further embodiment of the method aspect, there is provided a method for determining an analyte in a liquid medium, comprising:
[0060] (a) providing a probe comprising a piezoelectric crystal, electrodes on two opposite faces of the crystal, and comprising one or more metal plates carried on the surface of said crystal, said metal plates being the same or different than said electrodes, said metal plates having immobilized thereon a first member of a recognition pair; the pair comprising a second member being capable of binding to said analyte, the binding between said second member and said analyte being competitive to the binding of said second member to said immobilized member;
[0061] (b) measuring an initial resonance frequency of the probe;
[0062] (c) mixing said liquid medium with a solution containing said second member, the presence of said analyte in the medium causing binding thereto of said second member;
[0063] (d) contacting the mixture obtained in step (c) with said probe for a time sufficient to allow binding of said second member to the immobilized first member; and
[0064] (e) measuring a second resonance frequency of the probe, a second resonance frequency lower than the initial frequency indicating pressence of said analyte in the liquid medium (a relatively large decrease in resonance frequency meaning no or a small amount of analyte in the liquid medium; no or a small decrease in resonance frequency meaning a relatively large amount of the analyte in the liquid medium).
[0065] In accordance with the probe aspect of the invention there is provided a probe for use in the above method and system. The probe comprises a piezoelectric crystal having electrodes on two opposite faces of the crystal, and one or more metal plates carried on the surface of said crystal, Said metal plates being the same or different than said electrodes, the metal plates having immobilized thereon a first member of a recognition pair.
[0066] In order to cause a piezoelectric crystal to vibrate and eventually reach resonance frequency, the piezoelectric crystal has to be subjected to an alternating electrical field. The piezoelectric crystal used in accordance with the invention is typically a planar crystal having the form of a plate or a disc, and the electrodes which provide the alternating electrical field are typically planar metal electrodes attached to opposite faces of the crystal. The plates with the immobilized member of a recognition pair are preferably the same as the planar electrodes, in other words the electrodes serve both for the provision of an alternate electrical field and for immobilization of said first member.
[0067] An embodiment in accordance with the present invention where the analyte is measured directly by binding to the first member immobilized on the probe, will be referred to herein as “direct embodiment”. A direct embodiment is an embodiment where the analyte to be determined is the second member of the recognition pair. An embodiment in accordance with the invention, such as the second and third embodiments defined above, where the presence of analyte is measured indirectly, i.e. what is measured in essence is the depletion of the second member will be referred to herein as the “indirect embodiment”.
[0068] The method in accordance with the direct embodiment can be practiced in particular where the second member is a relatively large molecule or a complex of molecules, the binding of which to the immobilized member causing a considerable mass change. Where the analyte is a small molecule, it is usually preferred to practice the invention by an indirect embodiment, since binding of such an analyte to the probe will bring about only a very small change of mass. The second member in such a case will typically be a large molecule, e.g. an antibody with a binding affinity to said analyte.
[0069] An example of the direct embodiment of the invention is the determination of an antibody in a biological sample in which case the electrode has immobilized thereon an antigen to which said antibody specifically binds; or the determination of a protein antigen by the use of an electrode having immobilized thereon an anti-antigen antibody.
[0070] In accordance with the indirect embodiment, the immobilized member may be an immobilized analyte molecule or a molecule with a similar binding specificity to said second member as said analyte. Preferably, the immobilized analyte molecule has a lower binding affinity to said second member than the analyte, to allow effective depletion of said second member in the presence of the analyte.
[0071] An example of the indirect embodiment is the use of an immobilized antigen in order to determine an identical or related antigen in a biological sample to be tested. In accordance with this specific example, the biological sample, e.g. a plasma sample is first reacted with a reagent solution comprising an antibody which specifically binds to the antigen to be determined. After binding, the concentration of free (unbound) antibody becomes lower. Following an incubation period, a probe having antigen molecules immobilized thereon (the immobilized antigen, in this case being said immobilized member) is challenged with the reacted solution, and the determination of the free antibody then serves as an indication of said antigen in the tested biological sample. As will no doubt be appreciated by the artisan, the concentration of said free antibody will be in opposite correlation to the concentration of the antigen in the tested sample.
[0072] Furthermore, as will also be appreciated, an antibody in a tested biological sample rather than an antigen may be determined in an analogous manner, mutatis mutandis.
[0073] The analyte may at times also be a molecule suspended or dissolved in a gas, e.g. various airborne chemicals. In such a case, a gas suspected of containing an analyte is first passed (e.g. “bubbled”) through a suitable liquid which can dissolve the analyte, and this liquid is then tested for the presence of the analyte therein. Obviously, as gaseous chemicals are typically small molecules, determining of such analyte is preferably carried out by the indirect embodiment.
[0074] At times, in order to increase sensitivity, rather than determining the Δf response within the liquid, the probe is first dried and then the measurement of Δf is performed with the probe embedded in a gas or in a vacuum.
[0075] The recognition pair, of which a first member is immobilized on the probe's metal plate, may, for example, be an antigen-antibody, sugar-lectin, ligand-receptor, biotin-avidin, enzyme-substrate, oligonucleotide-complementary oligonucleotide, oligonucleotide-protein, and oligonucleotide-cell, and generally any pair of molecules with specific binding affinity to one another.
[0076] As a result of binding of the second member to the immobilized first member or the dissociation of the two members and the release of the second member from the probe, there is a change in mass which in turn results in a change in the resonance frequency (i.e. Δf response). The degree of Δf response correlates with the extent of binding or release of said second member and depends on the concentration of said analyte in the tested liquid surrounding the electrode. Thus, the extent of change in the resonance frequencies may be used, in accordance with a preferred embodiment of the invention, as an indication of the concentration of said analyte in the medium.
[0077] The metal plates carrying said immobilized member may be selected from a variety of metals, particularly such having the capability to associate chemically with, attach or chemisorb a sulphur-containing moiety. The metal plates are preferably made of or coated by metals such as gold, platinum, silver or copper.
[0078] The immobilized member is preferably immobilized on the surface of the metal plate by means of a linking group, which typically may have the following general formula (I):
Z—R 1 —Q (I)
[0079] wherein:
[0080] Z represents a sulphur-containing moiety which is capable of chemical association with, attachment to or chemisorption onto said metal;
[0081] R 1 represents a connecting group;
[0082] Q is a functional group which is capable of forming a covalent bond with a moiety of said first member of the recognition pair.
[0083] Z may for example be a sulphur atom, obtained from a thiol group, a disulphide group, a sulphonate group or sulphate groups.
[0084] R 1 may be a covalent bond or may be a peptide or polypeptide or may be selected from a very wide variety of suitable groups such as alkylene, alkenylene, alkynylene phenyl containing chains, and many others.
[0085] Particular examples of R 1 are a chemical bond or a group having the following formulae (IIa), (IIb), (IIc) or (IId):
[0086] wherein
[0087] R 2 or R 3 may be the same or different and represent straight or branch alkylene, alkenylene, alkynylene having 1-16 carbon atoms or represent a covalent bond,
[0088] A and B may be the same or different and represent O or S,
[0089] Ph is a phenyl group which is optionally substituted, e.g. by one or more members selected from the group consisting of SO 3 − or alkyl groups.
[0090] Q may for example be a functional group capable of binding to a carboxyl residue of a member of a recognition pair such as an amine group, a carboxyl group capable of binding to amine residues of the member of a recognition pair; an isocyanate or isothiocyanate croup or an acyl group capable of binding to an amine residue of the member of a recognition pair, or a halide group capable of binding to hydroxy residues of the protein or a polypeptide. Particular examples are the groups —NH 2 —COOH; —N═C═S; N═C═O; or an acyl group having the formula—R a —CO—G wherein G is a halogen such as Cl or OH, OR b , a
[0091] group or a
[0092] group; R a and R b being, independently a C 1 -C 12 alkenyl, alkenyl or a phenyl containing chain which is optionally substituted, e.g. by halogen.
[0093] Particular examples of such a linking group are cysteamine (III), cystamine (IV) and cysteic acid N-hydroxysuccinimide ester (V) having the formulae:
HS—CH 2 —CH 2 —NH 2 (III)
[0094] [0094]
[0095] wherein n and m are integers between 1-24, preferably 1-12 and most preferably 1-6.
[0096] The sensitivity of the method of the invention may be increased by the use of a molecule, moiety or a complex, which is complexed or bound to said second member. Such a sensitivity increasing moiety, molecule or complex will be referred to herein as “amplifier group”. The amplifier group may be a molecule or a complex having a binding affinity to said second member. Such an amplifier group may be made to bind to said second member after same has bound to the immobilized member or prior to such binding. The binding or complexing of the amplifier group to said second member will increase the mass change as a result of binding of said second member, or dissociation and release of said second member, as the case may be, and accordingly there will be a more noticeable Δf response, and hence an increase in sensitivity.
[0097] By increasing the sensitivity of the system in the manner described above, a Δf response can be measured even after binding or release of only a few second member molecules to the probe.
[0098] Binding of two members of a binding couple to one another is typically a high affinity binding, namely the two members do not dissociate easily from one another and even after proper rinsing, the second member may still remain substantially bound to the first immobilized member. In order to re-use the probe for a further measurement, there is a need to dissociate the second member from the immobilized member and remove it from the system. In accordance with an embodiment of the invention, the dissociation is achieved by means of a group, attached to the immobilized member which has two isomerization states and is capable of switching reversibly between its two states by exposure to two different types of energy (“isomerizable group”). Such an isomerizable group will typically have a first and second isomerization state and by reversibly switching from one state to the other, each such switching achieved with a different energy type, will cause a conformational change in the immobilized member which will bring about a change in the binding of affinity of the immobilized member to said analyte. Such a conformational change may, for example, be the occlusion of the binding site or a conformational change within the binding site which will cause a reduction in the binding affinity of the immobilized member to the second member. Such a reduction in affinity or vice versa may be defined as change or switch from a state of high affinity to a state of low, affinity or vice versa. In the first state, the immobilized member will have a high affinity to binding to the second member and after performing a measurement, the probe will be treated so that said isomerizable group will switch to the second state and consequently said second member will dissociate from the immobilized member. After removal of said analyte from the system, typically by rinsing and washing away of the rinsing solution, the probe will be further treated so that said isomerizable group switches back to said first state, whereby the probe will be ready for re-use.
[0099] The switching between the two states may be achieved by exposure to light of an appropriate wavelength within the infra red, visible or ultra violet range. The reactive isomerizable group will switch from said first state to said second state by exposure to light energy at a first wavelength and from a second state to said first state by exposure to a second, different than the first, wavelength. It is also possible that one of the switches will be achieved by mild thermal treatment.
[0100] Thus, in accordance with an embodiment of the invention the immobilized member of the recognition pair has or is linked to an isomerizable group reactive to exposure to light energy; said group having a first and a second state and is capable of being converted from the first state to the second state by exposure to irradiation of light of a first wavelength and from the second to the first state by exposure to irradiation of light of a second wavelength; the exposure inducing a change in affinity of the immobilized member for binding to said second member, whereby in the first state said immobilized member has a high affinity of binding to said second member such that said second member remains essentially bound to the immobilized member and in said second state said immobilized member has a low affinity of binding to said second member, such that the bound said second member is readily dissociated.
[0101] According to another embodiment of the invention said switching from the first state to the second state is by exposure to light energy but the switching from said second state to said first state is by mild thermal treatment.
[0102] In accordance with the process aspect of the invention, there is provided a process for preparing a probe for use in the above method and system, comprising:
[0103] (a) immobilizing said linking group onto the plate by chemical association attachment or chemisorption of the sulphur-containing moiety (Z); and
[0104] (b) binding the member of the recognition pair to be immobilized to said functional group (Q).
[0105] Steps (a) and (b) may also be reversed so that immobilization takes place before binding.
[0106] The process aspect of the invention further provides a process for preparing a probe carrying immobilized members which are attached to an isomerizable group, the process comprising:
[0107] (a) immobilizing said linking group onto the said plate by chemical association attachment or chemisorption of the sulphur-containing moiety;
[0108] (b) chemically modifying a member of said recognition pair with a photoisomerizable group whereby the modified member changes its binding affinity to the other member of the recognition pair by exposure to energy; and
[0109] (c) binding the modified member of the recognition pair to said functional group of the linking group immobilized on the electrode.
[0110] Steps (b) and (c) can be reversed such that the isomerizable group is bound to the member of the recognition pair after it has been immobilized in the electrode and so can steps (a) and (b).
[0111] The invention will now, be illustrated in the following description of some specific embodiments, with occasional reference to the annexed drawings, without prejudice to the generality of the foregoing.
DESCRIPTION OF THE DRAWINGS
[0112] In the drawings:
[0113] [0113]FIG. 1 shows a scheme of QCM for antibody analysis;
[0114] [0114]FIG. 2 shows a scheme for QCM analysis of an antigen by a QCM probe modified with an antigen monolayer and saturated with the Ab;
[0115] [0115]FIG. 3 shows a scheme for QCM analysis of an antigen by treatment of an antigen monolayer QCM probe with a mixture consisting of the analyte antigen and a constant, predetermined Ab concentration;
[0116] [0116]FIG. 4 shows a scheme for amplified QCM analysis of an Ab by the application of an anti-Ab or anti-Ab conjugate;
[0117] [0117]FIG. 5 shows an amplification of an antigen QCM analysis by the detachment of an Ab-conjugate complex from the QCM monolayer electrode;
[0118] [0118]FIG. 6 shows a possible configuration of Ab-conjugate complexes;
[0119] [0119]FIG. 7 shows an amplification of antigen QCM-analysis by treatment of an antigen monolayer QCM-probe with a mixture consisting of the antigen analyte and a fixed, predetermined, concentration of the Ab-conjugate complex;
[0120] [0120]FIG. 8 shows the regeneration of the sensing member by light isomerization;
[0121] [0121]FIG. 9 shows formulae of photoisomerizable groups and some examples of photo-induced and heat treatment-induced conformational changes;
[0122] [0122]FIG. 10 shows the organization of cystamine monolayer on a QCM gold (Au) electrode;
[0123] [0123]FIG. 11 shows a QCM-analysis of cystamine monolayer formation;
[0124] [0124]FIG. 12 shows the activation of the QCM-monolayer electrode by glutardialdehyde;
[0125] [0125]FIG. 13 shows QCM-analysis of the glutardialdehyde monolayer formation;
[0126] [0126]FIG. 14 shows the organization of HIV-1 antigen peptide on QCM Au-electrode:
[0127] [0127]FIG. 15 shows QCM-analysis of a 3000-titer serum of HIV-1 Ab;
[0128] [0128]FIG. 16 shows QCM-analysis of goat serum (titer 80) by the HIV-1 antigen electrode;
[0129] [0129]FIG. 17 shows the organization of a dinitrophenyl monolayer QCM electrode;
[0130] [0130]FIG. 18 shows a QCM-analysis of anti-DNP-Ab by dinitrophenyl antigen monolayer QCM electrode;
[0131] [0131]FIG. 19 shows organization of a fluorescein antigen monolayer QCM-electrode;
[0132] [0132]FIG. 20 shows QCM-analysis of 2,4-dinitrophenol, 1.4×10 −7 g·ml −1 , by detachment of DNP-Ab from the antigen-DNP-Ab monolayer electrode;
[0133] [0133]FIG. 21 shows the assembly of the dinitrophenyl antigen-DNP-biotin-avidin conjugate complex on a QCM-electrode;
[0134] [0134]FIG. 22 shows a scheme of QCM analysis of a sample solution that contains 2,4-dinitrophenol (DNP) by displacement of the dinitrophenyl antigen-DNP-biotin-avidin conjugate complex associated with a QCM electrode; and
[0135] [0135]FIG. 23 shows the Δf response in the system of FIG. 22 following exposure to 2.7×10 −8 g·ml −1 of DNP.
DETAILED DESCRIPTION OF THE INVENTION
[0136] The invention will now be illustrated by several specific embodiments, it being understood that these are given as examples only and that the invention is not limited thereto.
[0137] Reference is first being made to FIG. 1 showing a schematic representation of a manner of carrying out the invention according to the direct embodiment. A probe, generally designated 2 , comprises a piezoelectric crystal 4 and two gold electrodes 6 (for simplicity, only one electrode is schematically shown while another electrode is positioned on the opposite face of the crystal). Immobilized on the electrode are a plurality of antigens 8 which are members of a recognition pair, the pair consisting of these antigens and antibodies 10 which latter is the analyte to be determined. Electrodes 6 , as well as the corresponding electrodes in the other embodiments shown and described below, are connected to an electric or electronic circuitry (not show n) for generating alternating current between the pair of electrodes 6 and for measuring the resonance frequency of the electrodes.
[0138] Prior to determination of the analyte, an initial resonance frequency of the sensing member, is determined (f 0 ). Then, the probe 2 is challenged with a liquid containing the antibodies 10 which, if present in the liquid bind to the immobilized antigen 8 .
[0139] Consequently, there is a change in mass and an accompanying change, Δf, in resonance frequency. Δf is proportional to the mass of the bound antibodies, which in turn is proportional to the initial concentration of the antibodies in the tested liquid medium.
[0140] In a similar manner, mutatis mutandis, it is possible also to determine the concentration of an antigen in a liquid medium, by having the antibodies immobilized on the surface of the electrodes, particularly where the antigens are relatively large molecules, e.g. proteins.
[0141] Reference is now being made to FIG. 2, shouting a manner of carrying out the invention in accordance with the indirect embodiment. A probe 12 of this embodiment comprises a piezoelectric crystal 14 carrying gold electrodes 16 , having immobilized thereon antigens 18 (similarly as above the electrodes are connected to an electric or electronic circuitry for passing current and measurement of resonance frequency). In a first step (A), the sensing member is contacted with a medium comprising a large amount of antibodies 20 , which bind to the immobilized antigens, the amount of antibodies being sufficient to permit binding to saturation. At this stage, resonance frequency, f 0 , of the sensing member is determined (B). The sensing member is then challenged (C) with a liquid medium containing analyte 22 to be determined, which is capable of specific binding to antibody 20 , with a similar or at times larger binding affinity than that of the antibody 20 to immobilized member 18 . As a result of binding competition with the immobilized member, some of the bound antibodies 20 are released, and consequently there is a reduction in the immobilized mass and a resulting increase in the resonance frequency (D). This increase will be proportional to the amount of released mass, which is in turn proportional to the amount of agent in the tested liquid medium.
[0142] Reference is now being made to FIG. 3, showing an alternative embodiment of carrying out the invention according to the indirect embodiment. The probe 30 according to this embodiment comprises, similarly as before, piezoelectric crystal 32 carrying gold electrode 34 with immobilized antigens 36 . Antigen 36 is a member of a recognition pair, the other member being antibody 38 .
[0143] The system shown in FIG. 3 serves for the determination of analyte 40 . A tested liquid sample is first mixed (A) with antibody 38 . If the analyte 40 is present in the tested sample, antibody 38 will bind to analyte 40 and will consequently be eliminated from the system. The mixture is then reacted with the probe. If no antigen 40 is present in the tested medium (B), there will be a maximum binding of antibodies 40 to members 38 , and consequently a big increase in mass and a corresponding relatively big reduction in resonance frequency f′. Against this, where the liquid medium contains a large amount of analyte 40 , all the antibodies 38 will be eliminated from the system, and there will be practically no change in the resonance frequency, which will remain essentially equal to f 0 (C).
[0144] Reference is now made to FIG. 4, showing a scheme for an amplified QCM analysis of an analyte of a recognition pair. The scheme in this figure is essentially the same as in FIG. 1, the difference being the addition of amplifier group 40 , which can bind to or complex with antibody 42 . Amplifier group 40 functions to increase sensitivity of the system. After the antibody is allowed to bind to the immobilized antigens 44 , or simultaneously therewith, group 40 is brought into contact with the sensing member, whereby it binds to the antibodies 42 bound to the immobilized members 44 . Consequently, rather than a small Δf response, in this case there will be a much larger Δf response arising from the considerable increase of mass caused by group 40 .
[0145] [0145]FIG. 5 is an amplification version of the scheme shown in FIG. 2, making use of an amplifier group 46 . The probe 48 comprises a piezoelectric crystal 50 with gold electrodes 52 having immobilized thereon antigens 54 , which are one member of a recognition pair consisting also of antibodies 56 . Probe 48 is challenged (A) with a solution comprising antibodies 56 in an amount to ensure that antibodies 56 will bind to immobilized antigens 54 saturating all possible binding sites. Group 46 is then added (B), which then binds to antibodies 56 . Group 46 may, for example, be an antibody directed against antibodies 56 . At this stage a first reading, f 0 , is obtained (C) and then probe 48 is challenged with analyte 58 (D) which by a binding competition with immobilized antigen 54 with antigen 48 , brings to some release of complexes, consisting of antibodies 56 and group 46 from the probe. This will result in a relatively big mass reduction which will in turn result in a relatively big increase in resonance frequency (E).
[0146] The sensitivity of the system can be increased by creating large molecular complexes by means of complexation or conjugation. Examples are shown in FIG. 6. The basic configuration is a complex formed between an antibody 60 and an anti-antibody 61 shown in FIG. 6A. The sensitivity can be increased further by increasing the molecular complex mass, for example by binding or complexing to colloid particle 62 (FIG. 6B).
[0147] Another way to increase the molecular complex mass, shown in FIG. 6C, is to conjugate biotin molecules 63 to antibody 60 , and then by reacting the conjugated antibody 64 with avidin molecule 65 , a large complex 66 comprising mainly avidin molecule 65 and antibody 60 is formed. A further scheme, shown in FIG. 6D, is the complexation of avidin molecules in a similar fashion to the anti-antibody 61 .
[0148] [0148]FIG. 7 shows a system which is essentially similar to FIG. 3, with the addition of an amplifier group 71 bound to antibody 70 . The manner of performing of the method is essentially the same as that of FIG. 3, and the reader is referred to the description relating to FIG. 3 for explanations.
[0149] Reference is now being made to FIG. 8, which is a representation of another embodiment in accordance with the direct embodiment of the invention. This embodiment allows the regeneration of the probe after performance of the measurement for re-use in subsequent measurement. This feat is achieved, in accordance with this embodiment, by modifying the immobilized member 81 by isomerizable group 82 which has two states A and B, and is capable of switching reversibly between the two states by exposure to light of an energy hν 1 (having a wavelength λ 1 ) and energy hν 2 (having a wavelength λ 2 ). (This switching of the two states is show n schematically at the bottom of the figure.) The switching between the two isomerization states A and B causes a conformational change of the modified immobilized member which brings to a change in its affinity to binding to member 83 (in this case an antibody): in state A, the modified immobilized member is capable of binding member 83 with a high affinity; in state B, the affinity of binding to member 83 becomes very low.
[0150] The method of performance of the analyte determination (A) is essentially similar to FIG. 1 and the reader is referred to the description relating to this figure, the difference being that after finalizing the determination, the sensing member is illuminated by a light having a wavelength λ 1 (B), and consequently group 82 changes from state A to state B, which brings to a change in confirmation of immobilized member 82 , which causes release of member 83 . After rinsing (C), the electrode can be regenerated (D) by illumination with a light having a wavelength λ 2 .
[0151] Examples of five families of compounds which could be used as said group can be seen in FIG. 9—structures ( 1 ) to ( 5 ) namely: azobenzenes ( 1 ), spiropyranes ( 2 ), fulgides ( 3 ), thiophenefulgides ( 4 ) or malachite green ( 5 ). Examples of the structural change in three of these five families of compounds which occurs upon their exposure to irradiation of light energy of an appropriate wavelength is illustrated by schemes ( 6 ) to ( 8 ) of FIG. 9. Specifically scheme ( 6 ) exemplifies azobenzenes, scheme ( 7 ) spiropyranes and scheme ( 8 ) malachite green. These compounds all require structural modification to prepare a group which can be linked to the member of a recognition pair to be immobilized on the surface of the electrode. Accordingly, in the preferred embodiment these compounds are modified chemically to form active esters, amine, carboxylic acid, or halide derivatives. The presence of such moieties facilitates linkage of the group to the immobilized member of the recognition pair. Scheme ( 9 ) illustrates both the appropriate wavelengths of light energy required to change spiropyran from a first state (A) to a second state (B) in which it is in its merocyanine form and also the structures of the first and second isomer states with ( 9 B) and without ( 9 A) the N-hydroxysuccinimide ester moiety.
[0152] Examples of photoisomerizable active esters which can be seen in FIG. 9 are N-hydroxyoxsuccinimide ester of N-propionic acid spiropyran ( 10 ), N-hydroxyoxsuccinimide ester of 4-carboxy azobenzene ( 11 ) and N-hydroxyoxsuccinimide, ester of thiophenefulgide ( 12 ).
[0153] The invention will now be illustrated further by a description of experiments conducted in accordance with the invention.
[0154] 1. General
[0155] 1.1 Piezocrystals and Experimental Set-Up
[0156] All measurements were performed using 9 MHz quartz piezocrystals (QPC) (AT cut type) covered with a layer (ca. 0.2 cm 2 ) consisting of sputtered gold (ca. 3000A) on a titanium (Ti) substrate (ca. 500 A) (Seiko EG&G). The frequency measurements were performed using a Quartz Crystal Analyzer (model QCA917, Seiko EG&G) linked to a personal computer.
[0157] 1.2 Primary Electrode Modification by a Functionalized Monolayer for Antigen or Antibody Attachment. Specific Example—Modification of Au-quartz Crystal by a Cystamine Monolayer
[0158] The primary step for the organization of the sensing piezoelectric crystal involves the modification of the Au-electrode crystal by a functionalized thiolate monolayer that enables subsequent linkage of an antigen-Ab complex to the monolayer. Among the various possible functionalized monolayers (amine, carboxyl, hydroxy, diazonium) the organization of a cystamine monolayer is exemplified in FIG. 9. Quartz piezocrystal (QPC) was soaked in a solution of 0.2 M cystamine in water for 2 h. The frequency change during the cystamine adsorption on the electrode was a tool to detect the cystamine deposition, FIG. 10. The electrode was then rinsed thoroughly with water to remove the physically adsorbed cystamine. The frequency after the electrode rinsing was not altered as compared to the final value obtained during the adsorption process. That is, the cystamine molecules are strongly linked to the electrode surface. The observed frequency change Δf=−200 Hz (minus reflects frequency decrease) corresponds to the mass density of cystamine on the electrode corresponding to 1.16×10 −6 g·cm −2 or ca. 5.2×10 −9 mol·cm −2 (the densities are calculated using a geometrical area of the electrode).
[0159] 2. Experimental Results
[0160] 2.1 QCM Detection of HIV-1 Antibody Using an Electrode Modified with HIV-Peptide Antigen
[0161] An Au electrode modified with a primary cystamine monolayer was activated with glutaric dialdehyde (FIG. 12). The reaction was performed by treatment of the crystal in the QCM-cell with a 5% (v/v) glutaric dialdehyde solution in water for 20 min. at room temperature and following the frequency changes of the crystal during the reaction. (FIG. 13). The value Δf=−300 Hz corresponds to an electrode coverage of the electrode with glutaric dialdehyde of ca. 1.5×10 −8 mol·cm −2 . The resulting modified electrode was used for covalent immobilization of the HIV antigen (FIG. 14). The reaction was carried out by treatment of the crystal at room temperature in 0.01 M phosphate buffer, pH 7.4. containing 0.1 M NaCl and 0.4 mg·ml −1 HIV-antigen for 12 hours. The immobilization was monitored by measuring the frequency of the modified crystal. The final frequency change was Δf=−140 Hz that yields a density of the immobilized HIV-antigen that corresponds to 6.4×10 −11 mol·cm −2 . The electrode modified with the antigen was used for detection of HIV-1 antibody (FIG. 15). A frequency change of Δf=18 Hz after 10 minutes is observed for an HIV-1 sample with a titer corresponding to 3000.
[0162] The specifity of HIV-Ab detection was examined by treatment of the antigen electrode with goat serum (titer 80). A frequency decrease of only 2 Hz was observed after 10 minutes as a result of non-specific adsorption (FIG. 16). At lower measurement time intervals (4 minutes) the HIV-Ab causes a frequency change of Δf=15 Hz where the BSA control sample does not stimulate any detectable frequency change in the crystal frequency.
[0163] 2.2 A Dinitrophenol Antigen Monolayer QCM-Electrode for Analysis of DNP-Ab
[0164] A cystamine Au-modified electrode was obtained as described under 2.1. The modified QCM-electrode was treated with a solution of 0.2 M 3,5-dinitrosalicylic acid, N-hydroxy-sulfosuccinimide sodium salt (as a promoter) and 1-ethyl-3-(3-dinitromethylaminoporpyl)carbodiimide (EDC) as a coupling reagent in 0.05 M HEPES buffer, pH=7.3, to generate the dinitrophenol antigen monolayer on the surface (FIG. 17). The reaction was carried out for 2 h at room temperature. The frequency change of the crystal as a result of coupling of 3,5-dinitrosalicylic acid was −90 Hz, corresponding to an antigen coverage of 1.3×10 −12 mol·cm −2 .
[0165] The antigen QCM electrode was challenged with a DNP-Ab solution 1.4×10 −11 M. A frequency change of Δf=−30 Hz was observed after 800 seconds, indicating the adsorption of DNP-Ab to the crystal (FIG. 18).
[0166] 2.3 A Fluorescein Antigen Monolayer QCM-Electrode for Analysis of Anti-Fluorescein
[0167] A cystamine Au-modified electrode was obtained as described under 2.1. The modified electrode was reacted with fluorescein isothiocyanate to generate the antigen monolayer electrode (FIG. 19). Upon treatment of the electrode with antifluorescein Ab, 1×10 −6 mg·ml −1 , a frequency change of Δf=−60 Hz was observed.
[0168] 2.4 Dinitrophenol Antigen Monolayer Electrode with Bound DNP-Ab for 2,4 Dinitrophenol Analysis in a Sample According to the Configuration Shown in FIG. 2, Where Displacement of the Antibody Pre-Immobilized on the Antigen Monolayer Electrode Surface is Used for Detection of an Antigen in a Sample
[0169] A cystamine Au-modified electrode was obtained as described under 2.1. A solution of 0.2 M 3,5-dinitrosalicylic acid, N-hydroxysulfosuccinimide sodium salt (as a promoter) and 1-ethyl-3-(3-dinitromethylaminopropyl)carbodiimide (EDC) (as a coupling reagent) in 0.05 M HEPES buffer, pH 7.3, was used for further modification of the electrode surface with dinitrophenol units (FIG. 17). The reaction was performed for 2 h at room temperature and the final frequency change due to immobilization of 3,5-dinitrosalicylic acid was ca. −90 Hz, corresponding to an antigen coverage of 2.5×10 −9 mol·cm −2 . This antigen monolayer-modified electrode was used for specific adsorption of dinitrophenol antibody (monoclonal mouse IgE anti-DNP). The frequency change of the crystal as a result of Ab-binding was monitored again (similarly to FIG. 18). The final frequency change of Δf=−50 Hz resulted from the antibody deposition and gives the surface density of the antibody as ca. 1.93×10 −7 g·cm −2 . The antigen/antibody modified electrode was treated with an analyte sample aqueous solution containing 1.4×10 −7 g·ml −1 2,4-dinitrophenol (DNP) and the frequency change, resulting from the antibody desorption was recorded (FIG. 20). The displacement of the antibody was induced by its reaction with a new available antigen (DNP) being in the solution.
[0170] 2.5 Determination of 2,4-Dinitrophenol by Interaction with a Predetermined Concentration of DNP-Ab and Analysis of the Mixture with the Antigen Monolayer Crystal According to the Configuration of FIG. 3
[0171] The electrode was modified with 3,5-dinitrosalicylic acid as described under 2.2. This electrode was treated with an aqueous mixture that contains the sample analyte, 2,4-dinitrophenol, 1.4×10 −11 M and a predetermined DNP-Ab concentration of 1.4×10 −1 M. The final frequency change of the crystal was Δf=7 Hz after 800 seconds of interaction. For comparison treatment of the electrode with a sample that lacks 2,4-dinitrophenol but includes the predetermined DNP-Ab concentration, 1.85×10 −11 M, results in a frequency change of Δf=30 Hz after 800 seconds of interaction.
[0172] 2.6 Amplification of 2,4-Dinitrophenol Analysis by an Antigen-DNP-Ab-Biotinavidin Complex Associated with the Quartz Electrode According to the Configuration Shown in FIG. 5
[0173] 2.6.1. Preparation of Biotin Modified DNP-Ab
[0174] The 0.02 M DNP-antibody solution in 0.1 M phosphate buffer, pH 7.2 was reacted with 0.02 M biotin amidocaproate N-hydroxysuccinimide ester for 3 h at 25° C. The reaction mixture was dialyzed overnight at 4° C. against a 0.01 M phosphate buffer, pH 7.4, and the purified DNP-antibody-biotin was used to assemble the antigen-Ab-conjugate complex on the crystal electrode.
[0175] 2.6.2 Construction of an Antigen-DNP-Ab-Biotin-Avidin Complex on the QCM Electrode
[0176] The antigen-Ab-conjugate complex was assembled onto the crystal electrode as outlined in FIG. 21. An electrode that included a dinitrosalicylic acid monolayer was prepared as described under 2.2. The monolayer-modified crystal was treated with a solution of biotin-modified DNP-Ab, 1.25 mg·ml −1 . Adsorption of the modified Ab to the monolayer antigen induces frequency change of Δf=−50 Hz indicating a surface coverage by the Ab corresponding to 1.8×10 −12 mol·cm −2 . The resulting antigen-DNP-Ab-biotin monolayer electrode was treated with avidin solution, 1.0 mg·ml −1 . The resulting frequency change after 5 minutes as a result of formation of the biotin-avidin complex is Δf=−120 Hz which corresponds to a surface coverage of 5.5×10 −12 mol·cm −2 with the avidin complex.
[0177] 3. Analysis of 2,4-Dinitrophenol by the Antigen-DNP-Ab-Conjugate Complex QCM Electrode, According to the Configuration Shown in FIG. 5
[0178] The antigen-DNP-Ab-biotin-avidin complex QCM electrode was treated with a 2,4-dinitrophenol solution, 2.7×10 −8 g·ml −1 . The caused dissociation of the DNP-Ab complex conjugate from the electrode by the analyte antigen, as illustrated in FIG. 22, which was followed by the frequency changes of the crystal. A frequency change of Δf=30 Hz is observed after 400 seconds of interaction (FIG. 23). | Binding between two members of a recognition pair, e.g. antigen-antibody is determined by utilizing a probe comprising a piezoelectric crystal with electrodes on two opposite faces of the crystal. The crystal carries one or more metal plates which may be the same or different than said electrodes, the metal plates having immobilized thereon a first member of a recognition pair. Binding of a second member of the recognition pair to the first member, or dissociation between the two members and release of the second member from the probe, causes a change of immobilized mass which results in a change to the probe's resonance frequency. Said immobilized members may be immobilized on the surface of said metal plates by means of a linking group, having the following general (I): Z—R 1 —Q wherein Z represents a sulphur-containing moiety which is capable of chemical association with, attachment to or chemisorption onto said metal, R 1 represents a connecting group, Q is a functional group which is capable of forming a covalent bond with a moiety of said first member of the recognition pair. The immobilized member may have or be linked to an isomerizable group which changes its isomerization state as a result of exposure to energy. | 6 |
TECHNICAL FIELD
The present invention relates, in general, to a spray control system for a superheater and, in particular, to a superheater spray control system that can be utilized in variable pressure applications.
BACKGROUND ART
The control of superheater temperature may be accomplished through a spray attemperator and a control system that positions the spray flow control valve. Such a control system is based on steam temperature error. It has been found, however, that such a control system has a poor response time and can result in potentially unstable control.
The systems usually employed for boilers connected to steam turbines operating at a constant throttle pressure utilize various control approaches to achieve more stable operation and faster response time. For example, a system might control the attemperator outlet temperature to a set point which is adjusted based on outlet steam temperature error. Alternatively, a system could include a feed forward program for spray flow with the spray flow controlled to a demand determined by the program along with steam temperature error. Either of these approaches is quite satisfactory for applications involving constant pressure operation but is inadequate for variable pressure applications due to the variations in temperature within the superheater and the large changes in spray flow caused by variations in operating pressure. These inadequacies are further increased in those applications which include a pressure control valve within the superheater since such a control valve increases the number of possible operating conditions.
Because of the foregoing, it has become desirable to develop a superheater spray control system that can be utilized in variable pressure applications and can compensate for temperature variations within the superheater.
SUMMARY OF THE INVENTION
The present invention solves the problems associated with the prior art and other problems by providing a system for determining the superheater water spray demand in variable pressure applications. The system accomplishes the foregoing by predicting the superheater absorption and by adjusting same to compensate for temperature error to determine actual superheater absorption. The required superheater absorption is also determined based on actual unit operating conditions including the pressures at various locations within the unit. The system processes factors representative of the foregoing actual superheater absorption and the required superheater absorption and measurements representative of the enthalpy of the steam within the drum and the enthalpy of the water spray, along with a measurement of steam flow, to determine the superheater water spray demand.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a portion of a boiler water steam system.
FIG. 2 is a schematic diagram in the form of function blocks which produce an output indicative of superheater water spray demand.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings where the illustrations are for the purpose of describing the preferred embodiment of the present invention and are not intended to limit the invention hereto, FIG. 1 is a schematic diagram of a portion of a boiler water/steam system 10 for a turbine. The portion of the system 10 illustrated includes a steam drum 12 associated with a boiler (not shown), a primary superheater 14 connected to the output of the steam drum 12, and a secondary superheater 16 connected to the output of the primary superheater 14. The output of the steam drum 12 is shown as the steam flow W s minus the spray water applied to the superheater, shown as W spsh . The enthalpy of the steam flow from the steam drum 12 to the primary superheater 14 is shown as h g . The water spray applied to the primary superheater 14 and secondary superheater 16 is shown as W spsh , and this water spray has an enthalpy of h sp . The output of the secondary superheater 16 is shown as steam flow W s and this output has an enthalpy of h sho . From the foregoing, a simple heat and mass balance around the steam drum 12 to the output of the secondary superheater 16 can be performed to obtain the general equation for the amount of water spray needed by the superheater for a given amount of excess superheater absorption. In general, an equation representing the aforementioned schematic diagram under actual operating conditions, can be written as follows:
(W.sub.s -W.sub.spsh)h.sub.g +Actual Absorption=W.sub.s h.sub.sho (1)
A second equation representing the above under required conditions, i.e., no spray being applied to the superheater, is as follows:
W.sub.s h.sub.g +Required Absorption=W.sub.s h.sub.sho (2)
If equation (2) is subtracted from equation (1) and if Excess Absorption equals Actual Absorption minus Required Absorption, the following equations result: ##EQU1## It has been found that the actual absorption by the superheaters can be characterized as the product of the steam flow W s and some function of the steam flow f(W s ) and it has been similarly found that the required superheater absorption can be characterized as the product of the steam flow W s multiplied by the enthalpy of the steam at the outlet of the superheater (h sho ) minus the enthalpy of the steam (h g ) in the steam drum. The foregoing relationships are shown in the following equations: ##EQU2## From the foregoing, it is apparent that by predicting superheater absorption and by using this predicted absorption to determine actual superheater absorption, the water spray flow to the superheater W spsh can be determined.
Referring now to FIG. 2, a schematic diagram of a control system 20 in the form of function blocks is illustrated. This system 20 produces an output representative of superheater water spray demand W spsh based on superheater absorption. In this FIG., a steam flow measuring device 22 is provided and produces an output signal representative of steam flow W s . The output of the steam flow measuring device 22 is to a function block 24 which produces an expected value of superheater absorption. The output of the function block 24 is connected to an input of a multiplier 26 whose other input is connected to the output of an integrator 28. A superheater outlet temperature measuring device 30 is provided to produce an output signal representative of the temperature of the steam at the outlet of the superheater. The output of the superheater outlet temperature measuring output of a superheater outlet temperature set point device 34. The output of the difference function block 32 is connected to the input of the integrator 28, thus causing the multiplier 26 to compensate the temperature variations within the superheater which might affect spray flow thereto. In this manner, the output signal produced by the multiplier 26 represents the actual superheater absorption per unit system flow and the actual total superheater absorption and can be characterized by the factor W s f(W s ). The, output of the multiplier 26 is connected to one input of a multiplier 36 whose other input is connected to a function block 38 which acts as an adjustment for over/under fire transients. The output signal produced by multiplier 36 represents actual superheater absorption adjusted for over/under fire transients and is applied to the positive input a difference function block 40.
A superheater outlet pressure measuring device 42 is provided and produces an output signal representative of pressure at the outlet of the superheater. The output of the pressure measuring device 42 is connected to a function block 44 which produces an output signal that is a function of the pressure at the outlet of the superheater. This output signal is applied to the input of a multiplier 46 whose other input is connected to the output of the superheater outlet temperature set point device 34 via a function block 48 which produces an output signal that is a function of the temperature at the outlet of the superheater. The output signal produced by the multiplier 46 is representative of the enthalpy h sho of the steam at the outlet of the superheater and is applied to the positive input of a difference function block 50. A drum pressure measuring device 52 is provided and produces an output signal representative of the pressure within the steam drum 12. The output of the drum pressure measuring device 52 is connected to a function block 54 which produces an output signal that is a function of the pressure within the steam drum. The output of the function block 54 is connected to the negative input of the difference function block 50 and to the positive input of a difference function block 56. The output signal produced by the difference function block 50 is representative of the difference between the enthalpy h sho of the steam at the outlet of the superheater and the enthalpy h g of the steam in the drum. Thus, the output signal produced by the difference function block 50 is representative of the required superheater absorption and takes into consideration changes in spray flow caused by variations in operating pressure. The output of difference function block 50 is connected to the negative input of difference function block 40. . Inasmuch as the signal applied to the positive input of difference function block 40 is representative of the actual absorption of the superheater as adjusted for transients, the output signal produced by difference function block 40 is representative of the difference between the actual superheater absorption per unit steam flow and the required superheater of absorption per unit steam flow and is applied to an input of multiplier 58. The output of the steam flow measuring device 22 is also applied to a function block 60 which produces a signal representative of the enthalpy h sp of the spray (or alternately the spray temperature may be directly measured) and which is applied to the negative input of difference function block 56. The output signal produced by the difference function block 56 is representative of the difference between the enthalpy h g of the steam in the drum and the enthalpy h sp of the spray and is applied to a reciprocal function block 62 whose output is connected to the other input of multiplier 58. In this manner, the output signal produced by multiplier 58 is representative of the relationship ##EQU3## and is applied to a multiplier function block 64 whose other input is connected to the steam flow measuring device 22. The output of the multiplier 64 is representative of equation (4) and represents the superheater water spray demand.
Certain modifications and improvements will occur to those skilled in the art upon reading the foregoing. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability, but are properly within the scope of the following claims. | A superheater spray water control system for variable pressure applications produces an output signal representative of expected superheater absorption as a function of measured steam flow, compensates the signal for temperature variations within the superheater and adjusts it for over/under fire transients. An output signal representative of required superheater absorption from the drum to the superheater outlet, together with a spray water enthalpy signal obtained as a function of measured stem flow, is used with the compensated and adjusted actual superheater absorption and measured steam flow signals to produce a spray quantity demand signal. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a pump assembly of the kind having a single motor for driving a plurality of pumps. Also, the present invention relates to an improvement in a film processor having a plurality of tanks for holding solutions that periodically need to be replenished.
It is known to provide a single motor for driving two or more pumps. One example is a single motor, dual bellows pump Model No. 90885-000 sold by the Gorman Rupp Industries of Belleville, Ohio. Pump assemblies of this kind have two bellows pumps which are driven simultaneously by a single motor. It is known to use such pumps for replenishing solutions in a film processor having a plurality of tanks containing developer and fixer solutions needed for processing film, such as X-ray film. The solutions are depleted during development of film. When the motor is energized the pumps both are operated to simultaneously provide replenishment solutions to each of two tanks. The developer and fixer solutions typically to not need replenishment at the same rates. For example, one solution may need to be replenished 20 percent more than the other solution. Therefore a mechanical adjustment is provided for the bellows pumps which enables one bellows to pump from 0 to 100 percent of the capacity of the other bellows. This adjustment is crude and an inconvenient adjustment for the user. Also, the need for replenishment of the processing solutions is a function of the quantity of film processed in a particular time period and the amount of solution that evaporates from the tank during that time period.
While the replenishment system described above has operated satisfactorily, it suffers some disadvantages. For example, it cannot easily handle the situation where one tank is depleted of solution to an extent requiring replenishment prior to the time the other tank requires replenishment. Under the circumstances, if the motor is operated to replenish the depleted supply in the first tank, the second tank may be excessively replenished, resulting in an inaccurate chemical concentration, or the second tank may be filled beyond its capacity with the excess solution being diverted to a drain. In order to avoid such problems the depleted solution may not be replenished completely. Clearly there is a need to independently provide replenishment solutions to tanks in film processors in order that the precise amount of replenishment fluid can be provided to each tank based on its needs. This could be accomplished by providing two separate independent pumps with different motors, but such unnecessarily increases the cost of the film processor and complicates its controls.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide an improved pump assembly having a dual pump chamber and operated from a single motor wherein the individual pumps can be operated independently. Another object of the invention is to improve replenishment of solutions in a film processor by enabling each solution in each of several tanks to be independently replenished without simultaneously replenishing solutions in another tank unless the other tank also needs replenishment solution.
In accordance with one aspect of the invention an improved pump assembly is provided comprising multiple pump chambers. A single drive shaft is used for driving all of the pump chambers, and a single motor is coupled to the shaft for driving the shaft and operating the pumps. A plurality of clutches are provided, each of the clutches being coupled between the shaft and one of the pumps. Means are provided for selectively engaging the clutches individually or simultaneously in order to individually or simultaneously operate each of the pumps.
In accordance with another aspect of the invention an improvement is provided for a film processor having a plurality of tanks for solutions used in processing film. A plurality of pumps are provided for replenishment of solutions in the tanks when portions of solutions are depleted during processing of film. Each of the pumps is connected to one of the tanks and to a source of replenishment solutions for that tank. The improvement of invention comprises a single drive shaft used for driving all of the pumps, and a motor for rotating the shaft about an axis. A plurality of clutches are provided, each of the clutches being coupled to the shaft and, when engaged, to one of the pumps. Means are provided for selectively engaging the clutches, individually or simultaneously, in response to sensing the levels of solutions in the tanks.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following detailed description of the invention reference is made to the accompanying drawings in which:
FIG. 1 is a view illustrating an improved replenishment system for film processors or the like in accordance with the present invention, and incorporating the improved pump assembly of the invention, FIG. 1 being partially in elevation and partially diagrammatically illustrating the invention; and
FIG. 2 is a fragmentary cross-section view taken along line 2--2 of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
The improved replenishment system of the invention is suitable for use with a film processor having a plurality of tanks containing solutions that periodically need to be replenished. For example, two such tanks 12 and 14 are illustrated in the drawings and may receive solutions of developer and fixer as commonly used in film processing apparatus. During processing of film the solutions in the tanks are depleted and need to be replenished in order to maintain the quality of the processing operation. However, the tanks may be depleted at a non-uniform rate. As explained in more detail later, the invention permits the tanks to be replenished independently or simultaneously based on the condition of the solution in each tank.
Tanks 12 and 14 are replenished by two bellows pumps generally designated 16 and 18. Pump 16 comprises a bellows 20 secured at its lower end to a base or mounting member 22. The base has a cylindrical portion 23 that projects downwardly and receives a cam that drives the base in an up and down manner to compress and expand the bellows 20, as explained later. The upper end of the bellow is connected to conduits 24 and 26. Conduit 24 leads to a source of replenishment solution (not shown) for tank 12, and conduit 26 extends from the bellows pump to the tank 12. Check valves 28, 30 are provided between the conduits 24, 26 and the bellows 20. When bellows 20 is expanded from a compressed position to the position illustrated in FIG. 1, a suction is created in conduit 24 and replenishment solution is drawn through the conduit 24 into the bellows through the check valve 28. At this time the check valve 30 is closed. When the base 20 is driven upwardly to compress the bellows 20, solution within the bellows is forced upwardly through check valve 30 and conduit 26 into the tank 12. At this time the check valve 28 is closed. Thus during each cycle of expansion and compression of the bellows 20, solution is drawn from the source and delivered to the tank 12.
Bellows pump 18 is similar in construction to the pump 16. More specifically, pump 18 comprises a bellows 32 and a base 34. The base has a cylindrical portion 35 that projects downwardly for receiving a cam, as explained later. The upper end of the bellows is connected to conduits 36, 38 which have check valves 40, 42 located between the conduits and the bellows. When bellows 32 is expanded, it sucks replenishment solution from a source (not shown) through conduit 36 and check valve 40 into the bellows 32. At this time valve 42 is closed. When the bellows is compressed, replenishment solution within the bellows is forced out of the bellows through check valve 42 and conduit 38 into tank 14. Valve 40 is closed when the bellows is compressed. Pumps of this kind for providing replenishment solutions to tanks in a film processor are well known and need not be described in more detail here.
In accordance with the present invention a single shaft 44 is provided for operating both of the pumps 16, 18. The pumps are driven by eccentric cams 46, 48 that fit within cylindrical portions 23, 35 of the pump bases. The cams are mounted on the shaft by bearings 50, 52, respectively, so that the shaft can be rotated without movement of the cams. However, when one of the cams is coupled to the shaft for rotation about the axis of the shaft, it moves the respective bases 22, 34 of the pumps in an up and down direction to effect pumping action in the manner described above.
A motor 54 is mounted on a housing 56 and coupled to the shaft 44 so that operation of the motor rotates the shaft. Mounted on the shaft 44 are a pair of clutches 58, 60 which are closely adjacent the cams 46, 68, respectively. The clutches are securely fixed to the shaft 44 so that when the shaft is rotated by the motor, the clutches rotate with the shaft. The clutches can be electric spring clutches. One such clutch suitable for this use is a clutch Model No. EC25CCW6MMD24 manufactured by the Reell Precision Manufacturing Corporation of St. Paul, Minn. When such a clutch is energized, it is electromagnetically coupled to the associated cam 46 or 48 to effect conjoint rotation of the cam with the energized clutch, thereby operating the associated pump. More specifically, when clutch 58 is energized, it is magnetically coupled to the cam 46 so that operation of motor 54 to rotate the shaft 44 and clutch 58 also rotates the cam 46 to operate pump 16, thereby providing replenishment solution from conduit 24 to the pump and then through conduit 26 to tank 12. Similarly, when clutch 60 is energized pump 18 is operated to provide replenishment solution to tank 14.
A control system shown diagrammatically at 62 is provided for controlling operation of the various elements of the replenishment system. More specifically, the control system is coupled by lines 64, 66 to sensors 65, 67, respectively, in tanks 12, 14 so that a signal can be provided to the control system indicating when the solutions in tanks 12, 14 need replenishment. The sensors can detect the solution level in the tanks. The control system is also connected by conduit 68 to the motor 54 so that the motor can be operated by the control system. Also, the control system can energize clutches 58, 60 through lines 70, 72, respectively.
Operation of the apparatus will now be described. Assuming initially that the solution in tank 12 needs to be replenished and that the solution in tank 14 does not need to be replenished, sensor 65 associated with tank 12 will provide a signal through line 64 to the control system 62. The control system 62 will then turn on motor 54 through line 68 to effect rotation of shaft 44. Clutch 58 is rotated with the shaft, and when the control system sends a signal along line 70 to the clutch 58, it will be electro-magnetically coupled to the cam 46 to effect rotation of the cam about the axis of the shaft 44. As shown in FIG. 2, cam 46 is eccentrically mounted relative to shaft 44 so that when it is rotated about the shaft, it drives the base 22 of the pump 16 in a vertical direction. During a cycle of operation solution is drawn through conduit 24 and the check valve 28 into the bellows 20 and then discharged through check valve 30 and conduit 26 to the tank 12, thereby replenishing the solution in that tank. During this operation the clutch 60 remains deenergized and the shaft 44 rotates with respect to the cam 48 so that no solution is provided to tank 14.
In a similar manner, replenishment solution can be provided to tank 14 while no such solution is provided to tank 12. More specifically, if a need for replenishment in tank 14 is indicated by sensor 67, a signal is provided along line 66 to the control system 62 to effect rotation of motor 54 and shaft 44. A signal provided from the control system to clutch 60 effects coupling of the clutch to the cam 48 to operate pump 18 and provide replenishment solution to tank 14.
If the sensors in tanks 12 and 14 both indicate that replenishment solution is required, the control system can energize both clutches 58 and 60 simultaneously to operate both of the pumps 16, 18 and thereby simultaneously replenish solutions in both tanks 12, 14. Thus each tank is replenished based on the need for replenishment of solution in that tank. This is a distinct advantage over prior systems wherein both pumps 16, 18 are operated each time the motor 54 is turned on, and which can result in providing an inadequate amount of solution to one tank or an excess amount of solution to another tank, or require pumps 16, 18 having different (and carefully controlled) relative volumes.
The improved pump assembly of the present invention has been described in connection with replenishment of solutions in tanks of a film processor; however, it will be understood that such a pump assembly can be utilized with other kinds of apparatus where two pumps are driven from a single motor and where it is desired to operate the pumps independently or simultaneously.
While the invention has been described in detail in regard to specific embodiments thereof, it will be understood that various changes and modifications can be effected within the scope of the claims. | A dual chamber pump assembly comprises two separate bellows pumps driven from a single motor. The belows pumps can be operated independently, or simultanously, by selectively engaging clutches coupled to the motor and the pumps. A replenishment system for a film processor incorporating such a pump assembly has a plurality of tanks for solutions used in processing film, and each of the pumps is connected to one of the tanks and to a source of replenishment solution for its respective tank. By selectively engaging the clutches for the bellows pumps, the tanks can be replenished independently or simultaneously, as needed. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to a tri-layer structured metal composite oxides material which used in a catalyst coat for purifying vehicle exhaust gas, and the method for manufacturing the same.
BACKGROUND OF THE INVENTION
[0002] The main content of vehicle exhaust gas is carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx). With a catalyst utilized in exhaustion system, CO & HC could be oxidized to carbon dioxide (CO 2 ) and water (H 2 O); meanwhile, nitrogen oxide (NO x ) could be deoxidized to nitrogen (N 2 ) in order to purify the vehicle exhaustion. This kind of catalyst is usually called as a three-way catalyst. A three-way catalyst contains two parts: a honeycombed ceramic carrier or a metal carrier, and a catalyst coat layer attached on the carrier. A catalyst coat is usually composed of oxide materials having a relatively large surface area, e.g., alumina, oxygen storage materials and the active components of noble metals, e.g., at least one kind among Platinum (Pt), Palladium (Pd), Rhodium (Rh), that disperse on the surface of oxide materials or oxygen storage materials. The oxygen storage materials are usually composite oxides containing cerium & zirconium that adjusts the ratio of oxidized components and deoxidized components in vehicle exhaustion by absorbing the oxygen from the exhaustion or releasing oxygen from itself through the process of CO and HC oxidization and simultaneous deoxidization of NO x .
[0003] In order to improve the HO conversion efficiency during a vehicle cold start, a three way catalyst is usually placed on a location close to the engine manifold exhaustion pipe exit. When a vehicle runs at high speeds, the temperature of catalyst's coat layer could reach approximately between 900° c and 1100° c. Under such high temperatures, the catalyst coat materials can be charred and then its surface area is reduced and oxygen storage capacity is weakened. The noble metal grains that disperse on its surface gradually aggregate and become embedded into the collapsed tunnel caused by sinter. Consequently, the active area on catalyst surface decreases and the conversion efficiency of CO, HO and NO x is lowered. Moreover, under the high temperature and with sufficient oxygen, the noble metal Rhodium (Rh) alloys with alumina (γ-Al 2 O 3 ) and cerium bioxide (CeO 2 ) in the coat layer. The process decreases the efficiency of the catalysis of Rhodium (Rh) as well.
[0004] The current technology prepares the three way catalyst coat layer by mixing the powders of alumina (γ-Al 2 O 3 ) and oxygen storage materials physically and subsequent grinding by a ball mill with other auxiliary agents. The coat layer materials prepared this way are unstable under high temperatures. The surface area is relatively small after ten-hour high temperature aging process under between 900° c and 1100° c. In addition, the three-way catalyst with the coat layer covered with noble metal interacts poorly with CO, HO and NO x after the high temperature aging process. Furthermore, the process uses cerium and zirconium composite oxide powders with large particle sizes and the oxygen storage process mainly takes place on the surface of cerium and zirconium composite oxide particles while buried part of the particles could not store oxygen. In order to improve the three way catalyst efficiency, metal composite oxides material used in three way catalyst coat and method for manufacturing the same had been published. For example, U.S. Pat. No. 6,576,207 by Degussa Company discloses a method of co-precipitation to disperse cerium and zirconium composite oxide nano particles on the surface of γ-Al 2 O 3 powders which have high specific surface area to form a double-layer structure in order to improve material stability under high temperatures and dynamic oxygen storage efficiency of cerium and zirconium composite oxide; similarly, US Patent Application No. US2007179054 from Mazda Company discloses a reverse co-precipitation method to disperse cerium and zirconium composite oxide nano particles on the surface of γ-Al 2 O 3 powder to form a double-layer structure. Generally speaking, cerium and zirconium composite oxide with rich cerium is better in oxygen storage capability than cerium and zirconium composite oxide with rich zirconium, but the former has a weaker thermo-stability is weaker than the latter. Therefore, the double-layer structure from afore-mentioned patent application publication has such a shortage: cerium and zirconium oxygen storage material on surface could not meet the requirement of oxygen storage capability and thermo stability at the same time.
SUMMARY OF THE INVENTION
[0005] An object of the present invention is to overcome the shortage of existing technology, and to provide a tri-layer structured metal composite oxides material having improved thermo stability and pollution treatment capability.
[0006] Another object of the present invention is to provide a method of preparing afore-mentioned tri-layer structured metal composite oxides material.
[0007] According to one embodiment of the present invention, a metal composite oxides material has a tri-layer structure characterized by: an inner layer that is alumina, a middle layer and an outer layer both are cerium and zirconium oxide adulterated with rare earth in which cerium oxide has been removed, when a Ce/Zr atomic ratio in cerium and zirconium composite oxide of outer layer is ≧1, a Ce/Zr atomic ratio in cerium and zirconium composite oxide of middle layer is ≦1/3; and when a Ce/Zr atomic ratio in cerium and zirconium composite oxide of outer layer is ≦1/3, a Ce/Zr atomic ratio in cerium and zirconium composite oxide of middle layer is ≧1.
[0008] Mass ratio of inner alumina and middle layer is 10:5˜10:1.
[0009] Mass ratio of middle layer and outer layer is 1:3˜4:1
[0010] Mass weight of Cerium oxide removed rare earth in cerium and zirconium composite oxide is 2%˜10%
[0011] The method of preparing tri-layer structured metal composite oxides material in present invention comprising below steps:
[0000] First step: dissolving Ce 3+ , Zr 4+ and adulterated rare earth in deionized water,
[0012] wherein the atomic ratio of Ce 3+ , Zr 4+ and adulterated rare earth is the same as that in the middle layer, then mixing with citric acid aqueous solution, stirring to form complex solution of metal iron and citric acid, in solution in which a molar concentration of citric acid ≧(3× molar concentration of Ce 3+ +4× molar concentration of Zr 4+ )/3, adding alumina powder having a particle size of 90 μm and specific surface area ≧130 m2/g into complex solution to form suspension solution, then evaporating to dryness the suspension solution under temperature between 60˜100° C., desiccating for 5˜12 hour under temperature between 120˜200° C., baking for 3˜6 hour under temperature between 450° C.˜650° C., and rubbing the baked power to obtain a double-layer structured powder in which a mass ratio of alumina in inner layer and cerium and zirconium composite oxide adulterated with rare earth on surface is 10:5˜10:1.
[0000] Second step: dissolving Ce 3+ , Zr 4+ and adulterated rare earth in deionized water, wherein the atomic ratio of Ce 3+ , Zr 4+ and adulterated rare earth is the same as that in the outer layer, then mixing with citric acid aqueous solution, stirring to form complex solution of metal iron and citric acid, in solution in which a molar concentration of citric acid (3× molar concentration of Ce 34 plus 4× molar concentration of Zr 4+ )/3, adding the double-layer structured powder prepared by first step into complex solution to form suspension solution, the particle size of mentioned powder is 2 μm˜60 μm, evaporating to dryness the suspension solution under temperature between 60° C. and 100° C., desiccating for 5˜12 hour under temperature between 120° C. and 200° C., baking for 3˜6 hour under temperature between 450° C.˜650° C., and rubbing the baked power to obtain a tri-layer structured metal composite oxides powder.
[0013] A noble metal catalyst used for purifying vehicle exhaust gas comprising the tri-layer structured metal composite oxides material. The present invention has following characterization:
[0014] (1) Cerium and zirconium composite oxide nano crystal particles are dispersed directly on surface of alumina particle having large specific surface area by Sol-Gel method, instead of being mixed physically cerium and zirconium oxide powder with alumina powder. On the one hand, high dispersion of cerium and zirconium oxide on the surface of alumina particle improves the surface of cerium and zirconium oxide, and restrain accretion of cerium and zirconium oxide crystal particle under high temperature; on the other hand, dispersion of cerium and zirconium oxide on surface of alumina particle could fully exert the capability of oxygen storage.
[0015] (2) Alumina is the inner layer of tri-layer structure, the contact of alumina particle will be difficult by separation of middle layer and outer layer, thus increase the thermo stability of alumina.
[0016] (3) Ce/Zr atomic ratio of cerium and zirconium oxide in middle layer and in outer layer is different, which could be chosen by application of catalyst: when the noble metal carried on metal composite oxides surface is Pd, the catalyst which outer layer cerium and zirconium oxide has Ce/Zr atomic ratio ≧1 is more efficient on HC and CO conversion than those catalyst which outer layer cerium and zirconium oxide has Ce/Zr atomic ratio ≦1, and cerium and zirconium oxide in middle layer whose Ce/Zr atomic ratio ≦1/3 could improve the stability of outer layer and catalyst under high temperature; when the noble metal carried on metal oxide surface is Rh, Ce/Zr atomic ratio of cerium and zirconium oxide in outer layer ≦1/3 will restrain Rh alloy with Ce under the condition of rich oxygen and high temperature, cerium and zirconium oxide whose Ce/Zr atomic ratio used in the middle layer could improve oxygen storage capability of catalyst.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Further explanation to the present invention will be described in combination with specific examples.
Example 1
[0018] Step 1: dissolve 500 g citric acid in 500 g deionized water to obtain 1000 g citric acid solution, and dissolve 214 g Z r O(NO 3 ) 2 .5H 2 O, 434 g Ce(NO 3 ) 3 .6H 2 O and 35.5 g La(NO 3 ).6H 2 O in 600 g deionized water to obtain another solution. Mix two solutions and stir for 1 hour, add 1337 g alumina powder (particle size is 90 μm and specific surface area is 150 m 2 /g) to obtain a suspension solution. Then heat the suspension solution to 80° C., stir the solution till it dry up, desiccate the residue for 12 hour at 120° C., then bake 5 hour at 600° C., and mill the cool baked powder to obtain a double-layer structured light yellow powder, i.e., powder 1, in which a mass ratio of alumina I cerium and zirconium oxide is 5:1, a Ce/Zr ratio of cerium and zirconium oxide is 3/2, and a weight ratio of La 2 O 3 in cerium and zirconium oxide is 5%.
[0019] Step 2: dissolve 500 g citric acid in 500 g deionized water to obtain 1000 g citric acid solution, dissolve 491 g ZrO(NO 3 )2.5H 2 O, 166 g Ce(NO 3 ) 3 .6H 2 O and 35.5 g La(NO 3 ).6H 2 O in 600 g deionized water to obtain another solution, mix the two solutions and stir for 1 hour, add 1337 g powder 1 to obtain a suspension solution. Then heat the suspension solution to 80° C., stir the solution till it dry up, desiccate the residue for 12 hour at 120° C., then bake 5 hour at 600° C., and mill the cool baked powder to obtain a tri-layer structured metal composite oxides powder, i.e., powder 3, in which a mass ratio of alumina/cerium and zirconium oxide in middle layer is 5:1, a mass ratio of cerium and zirconium oxide in middle layer/cerium and zirconium oxide in outer layer is 1:1, a Ce/Zr ratio of cerium and zirconium oxide in middle layer is 3/2, a weight ratio of La 2 O 3 is 5%; a Ce/Zr of cerium and zirconium oxide in outer layer is 1/4, a weight ratio of La 2 O 3 is 5%.
Example 2
[0020] Step 1: dissolve 500 g citric acid in 500 g deionized water to obtain 1000 g citric acid solution, dissolve 491 g ZrO(NO 3 ) 2 .5H 2 O, 166 g Ce(NO 3 ) 3 .6H 2 O and 35.5 g La(NO 3 ).6H 2 O in 600 g deionized water to obtain another solution, mix two solutions and stir for 1 hour, add 1337 g alumina powder (particle size is 45 μm and specific surface area is 150 m 2 /g) to obtain a suspension solution. Then heat the suspension solution to 80° C., stir the solution till it dry up, desiccate the residue for 12 hour at 120° C., bake 5 hour at 600° C., and then mill the cool baked powder to obtain a double-layer structured light yellow powder, i.e., powder 2, in which a mass ratio of alumina/cerium and zirconium oxide is 5:1, a Ce/Zr ratio of cerium and zirconium oxide is 1/4, a weight ratio of La 2 O 3 in cerium and zirconium oxide is 5%.
[0021] Step 2: dissolve 500 g citric acid in 500 g deionized water to obtain 1000 g citric acid solution, dissolve 214 g ZrO(NO 3 ) 2 .5H 2 O, 434 g Ce(NO 3 ) 3 .6H 2 O and 35.5 g La(NO 3 ).6H 2 O in 600 g deionized water to obtain another solution, mix two solutions and stir for 1 hour, add 1337 g powder 2 to obtain a suspension solution. Then heat suspension solution to 80° C., stir the solution till it dry up, desiccate the residue for 12 hour at 120° C., then bake 5 hour at 600° C., and mill the cool baked powder to obtain a tri-layer structured metal composite oxides powder, i.e., powder 4: in which a mass ratio of alumina/cerium and zirconium oxide in middle layer is 5:1, a mass ratio of cerium and zirconium oxide in the middle layer/cerium and zirconium oxide in outer layer is 1:1, a Ce/Zr ratio of cerium and zirconium oxide in middle layer is 1/4, a weight ratio of La 2 O 3 is 5%; a Ce/Zr ratio of cerium and zirconium oxide in outer layer is 3/2, a weight ratio of La 2 O 3 is 5%.
Example 3
The preparation of Three Way Catalyst A (Rh-Powder 2/Pd-Powder 1/Ceramic Carrier)
[0022] Pd coat: Powder 1 is mixed with deionized water uniformly, drop Pd(NO 3 ) 3 solution slowly, ball mill this suspension solution to obtain a slurry I which has average particle size of 50 μm and solids content of 45%. Coat a certain amount of slurry I on honeycombed ceramic carrier whose is φ20 mm×40 mm, and 400 cpsi/6.5 mil (volume 12.56 ml), then dry and bake it.
[0023] Rh coat: Powder 2 is mixed with deionized water uniformly, drop Rh(NO 3 ) 3 solution slowly, ball mill this suspension solution to obtain slurry II which has average particle size of 50 μm and solids content of 40%. Coat a certain amount of slurry II on carrier which already coated by Pd, then dry and bake it, thereby obtain a three way catalyst A: Rh-powder 2/Pd-powder 1/ceramic carrier that comprise the below components.
[0000]
φ20 mm × 40 mm,
Carrier
400 cpsi/6.5 mil
Powder 1
70 g/L
Powder 2
50 g/L
Pd
30 g/ft 3
Rh
6 g/ft 3
1
70 g/L
2
50 g/L
Pd
30 g/ft 3
Rh
6 g/ft 3
Example 4
The Preparation of Three Way Catalyst B (Rh-Powder 3/Pd-Powder 4/Ceramic Carrier)
[0024] The preparation process is the same as the process of preparing catalyst A, except powder 4 is replaced with powder 1 and powder 3 is replaced with powder 2. Catalyst B comprises the below components.
[0000]
φ20 mm × 40 mm,
Carrier
400 cpsi/6.5 mil
Powder 4
70 g/L
Powder 3
50 g/L
Pd
30 g/ft 3
Rh
6 g/ft 3
Example 5
The Preparation of Three Way Catalyst C (Rh-Powder 4/Pd-Powder 3/Ceramic Carrier)
[0025] The preparation process is the same as the process of preparing catalyst A, except powder 3 is replaced with powder 1 and powder 4 is replaced with powder 2. Catalyst C comprises the below components.
[0000]
φ20 mm × 40 mm,
Carrier
400 cpsi/6.5 mil
Powder 3
70 g/L
Powder 4
50 g/L
Pd
30 g/ft 3
Rh
6 g/ft 3
Example 6
Catalysis Performance Evaluation of Catalyst A-C
[0026] Before conduct catalysis performance test, all catalyst had been aging for 20 hour in 10 volume % H 2 O/90% air at 1050° C. Using simulate evaluation system to test the performance of catalyst. Test objects are light-off temperature T50 (catalyst inlet temperature correspond to contamination conversion reach 50%) and dynamic conversion at 450° C. of HC, CO and NO x , below table show the composition of synthesis gas in a simulate evaluation system while test inlet temperature.
[0000] Composition Composition Composition Composition C 3 H 6 333 ppm O 2 1.15 vol. % C 3 H 6 167 ppm CO 2 14 vol. % CO 1.5 vol. % H 2 O 10 vol. % H 2 0.5 vol. % N 2 balance gas NO x 1000 ppm LambdaValue 0.998
Inlet temperature of catalyst gradually raise to 500° C. in speed of 60° C./min, air speed of synthesis gas is 60000 h −1 , the value of light-off temperature T50 showing in below table
[0000] HC T50/ CO T50/ NOx T50/ Catalyst ° C. ° C. ° C. A 314 293 297 B 306 286 288 C 312 290 296
Keep catalyst Inlet temperature at 450° C. while test dynamic conversion, Lambda Value of synthesis gas is 0.998±0.03, surge frequency is 1 HZ, the value of dynamic conversion showing in below table
[0000] Conversion Conversion Conversion Catalyst of HC % of CO/ % of NO x / % A 84 90 87 B 92 95 94 C 88 93 89
Catalyst performance evaluation result indicates that after aging in hot water at 1050° C., catalyst B has the highest catalysis efficiency. Compared with Catalyst A which prepared by double-layer structured metal composite oxides, three kinds of infectant treated by catalyst B and C will have higher conversion and lower light-off temperature. The contrast between catalyst B and catalyst C shows that while it carry different noble, the chose of Ce/Zr of cerium and zirconium oxide in middle layer and outer layer among metal composite oxides will effect the high temperature stability. | The present invention disclosed a tri-layer structured metal composite oxides material which used in a catalyst coat for purifying vehicle exhaust gas, and the method for manufacturing the same. | 8 |
GOVERNMENT LICENSE RIGHTS
The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Contract No. N00019-96-C-0128 awarded by NAVAIR.
TECHNICAL FIELD
The present invention relates to the field of mechanical flight control systems.
DESCRIPTION OF THE PRIOR ART
Mechanical flight control systems (MFCSs) have been in use for many years for aiding in the control of various types of aircraft. A MFCS typically used in helicopters is a cyclic control system (CCS). A CCS commonly includes a pilot input device, usually a stick controlled by the right hand of a pilot, connected to hydraulic actuators by various mechanical linkages. The hydraulic actuators are often arranged to connect to and cause changes in the physical orientation of a swash plate. Lateral, forward, and aft movement control of the helicopter is primarily controlled by the physical orientation of the swash plate. A CCS is normally designed such that when a pilot displaces a cyclic stick from a centered position, the attached mechanical linkages cause the actuators to adjust the physical orientation of the swash plate such that the helicopter tends to move in the direction of the stick movement.
A CCS is often described as having particular mechanical characteristics. The mechanical characteristic of a CCS are typically summarized as the effective forces perceived by the pilot through the cyclic stick as the pilot manipulates the cyclic stick. The CCS is normally designed to be balanced such that such that without pilot intervention, the cyclic stick centers to a position called “trim position”. When the cyclic stick is centered or at trim position, no lateral, forward, or aft movement of the helicopter occurs due to the CCS. The major contributing forces which combine to establish the mechanical characteristic of a CCS include: (1) a “breakout force” or “return-to-center force” which is a constant force applied toward centering the cyclic stick to trim position despite how far the cyclic stick is displaced and despite at what velocity the cyclic stick is moved, (2) a “gradient force” or “spring force” that also returns the cyclic stick to a centered position but varies with how far the cyclic stick is displaced from trim position such that the farther the cyclic stick is moved, the stronger the force applied toward centering the cyclic stick to trim position, (3) a constant “friction force” that is opposite to the direction of cyclic stick movement, (4) a “damping force” opposite to the direction of cyclic stick movement and which varies with the velocity at which the cyclic stick is moved, and (5) a “hard stop force” which simulates a mechanical limit of travel of the cyclic stick.
The sources of the above described forces vary. Breakout force often emanates from the combination of mechanical balancing of a CCS, the breakout friction force associated with the joints connecting the various mechanical linkages, and the spring preload force associated with the force-gradient cartridges. Gradient force and spring preload both typically primarily emanate from the inclusion of “force-gradient cartridges” situated along a force path between the cyclic stick and the connection to swash plate actuators. Force-gradient cartridges are typically canisters comprising bi-directional spring elements. Hard stop forces are normally forces transmitted to the cyclic stick for purposes of informing the pilot that the CCS is at its control limit for the current directional command.
Automatic flight control systems (AFCSs) are often incorporated into CCSs such that motors or other devices provide mechanical input to the CCS resulting in automated holding of the cyclic stick and/or automated adjustment of the “trim position”. It is common to incorporate a “trim release button” on the cyclic stick which allows the pilot to move the cyclic to any desired position and then release the trim release button to command the AFCS to hold the current cyclic stick position. Often, the “trim position” or “attitude” can be adjusted by moving a four-way thumb switch on the cyclic stick. If a CCS has good mechanical characteristics, it is easy for the pilot to “push through” the cyclic stick position held by the AFCS by applying force to the cyclic stick without disengaging the AFCS.
If the friction forces of a CCS are too high and/or the mechanical leverage offered by the cyclic stick design is too low, significant negative impacts on the mechanical characteristics of the CCS may exists. For example, a cyclic stick offering a lowered mechanical leverage results in higher breakout forces and amplifies CCS mechanical imbalance resulting in poor control harmony. Where frictional forces cannot otherwise be reduced adequately to accommodate the low leverage cyclic stick, force-gradient cartridges fail to provide proper levels of spring force. With low spring force levels, poor cyclic stick centering occurs during manual operation of CCS and the AFCS is prevented from “back-driving” the CCS. While the above described MFCS advancements represent significant developments in MFCS design, considerable shortcomings remain.
SUMMARY OF THE INVENTION
There is a need for an improved mechanical flight control system.
Therefore, it is an object of the present invention to provide an improved mechanical flight control system which provides a lower perceived system friction.
This object is achieved by providing a CCS in which a cyclic secondary boost actuator is connected in a parallel load path between an upstream portion of the CCS and a downstream portion of the CCS.
The present invention provides significant advantages, including: (1) improved cyclic stick centering to the trim position; (2) masking from the pilot all friction and mass imbalances associated with the downstream portion of the CCS; (3) allowing pilot to perceive the friction associated with only the upstream portion of the CCS, and (4) providing back-driving or push through capability during use of an AFCS of a CCS with unequal friction forces in the upstream portion of a CCS and the downstream portion of the same CCS.
Additional objectives, features, and advantages will be apparent in the written description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. However, the invention itself, as well as, a preferred mode of use, and further objectives and advantages thereof, will best be understood by reference to the following detailed description when read in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view of the preferred embodiment of a helicopter according to the present invention;
FIGS. 2 and 3 are perspective views of the preferred embodiment of a CSS according to the present invention;
FIGS. 4-7 are perspective and side views of a longitudinal boost assembly of the CSS of FIGS. 2 and 3 ; and
FIGS. 8-11 are perspective and side views of a lateral boost assembly of the CSS of FIGS. 2 and 3 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is an improved mechanical flight control system (MFCS) which allows an upstream portion of the MFCS to operate with lower friction and lower preloads than a downstream portion of the MFCS. While specific reference is made to a cyclic control system CCS for a helicopter, the present invention may alternatively be incorporated with any other mechanical control system where operating an upstream input control portion having lower friction than a downstream output control portion is desired and/or is beneficial.
FIG. 1 depicts a helicopter 101 incorporating a CCS (not shown) according to the present invention. Helicopter 101 has a fuselage 103 , a crew compartment 105 , and rotor blades 107 powered by a power plant (not shown) and driven by a mast 109 . Cyclic sticks (not shown) of CCS and other portions (not shown) of CCS are located within crew compartment 105 where a pilot and copilot are seated during operation of helicopter 101 . Helicopter 101 also has a swash plate (not shown) which is physically manipulated in part by CCS. Physical manipulations of the swash plate results in altered cyclic control outputs. Of course CCS may optionally include an auto-pilot feature for controlling a cyclic input.
Referring now to FIGS. 2 and 3 in the drawings, perspective views of the preferred embodiment of a CCS according to the present invention are illustrated. CCS 111 comprises an upstream portion 113 , a downstream portion 115 , and a boosting means 117 connected to both upstream portion 113 and downstream portion 115 . CCS 111 also comprises a lateral load path 119 and a longitudinal load path 121 . In this embodiment of the present invention, boosting means 117 comprises a lateral boost assembly 123 and a longitudinal boost assembly 125 . Generally, boost assemblies 123 , 125 are installed parallel to the convention direct load path rather than in series with the conventional direct load path. Forces are transferred from upstream portion 113 of lateral load path 119 to downstream portion 115 of lateral load path 119 through lateral boost assembly 123 . Forces are transferred from upstream portion 113 of longitudinal load path 119 to downstream portion 115 of longitudinal load path 119 through longitudinal boost assembly 125 . Both lateral boost assembly 123 and longitudinal boost assembly 125 may be shaped, sized, and otherwise adapted to achieve a particular input/output leverage ratio between various system elements. Upstream portion 113 has lower inherent friction than downstream portion 115 .
Upstream portion 113 and downstream portion 115 of CCS further comprise cyclic sticks 127 and associated buttons (not labeled) for inputting pilot commands by moving sticks 127 and pressing buttons, force-gradient cartridges 129 for introducing spring force to CCS 111 mechanical characteristics, trim motor assemblies 131 for actuating CCS 111 elements during autopilot use, and various fixed mounts 133 (all not labeled) for attaching stationary portions of CCS 111 to stationary features (not shown) of interior portions of a helicopter fuselage (not shown) such that movable interlinked elements such as tubular control linkages 135 (not all labeled), mechanical idlers 137 (not all labeled), and mechanical bellcrancks 139 (not all labeled) are movable with relation to the stationary features of interior portions of the helicopter fuselage. While bearings are typically used to connect discreet linking elements, bearings are not labeled. A lateral output linkage 141 and a longitudinal output linkage 143 transmit forces from lateral boost assembly 123 and longitudinal boost assembly 125 , respectively, to other structures (not shown) which ultimately control swash plate actuators (not shown). The swash plate actuators are hydraulic actuators controlled and activated by movements of lateral output linkage 141 and a longitudinal output linkage 143 .
Referring now to FIGS. 4-7 , the preferred embodiment of longitudinal boost assembly 125 is illustrated. Assembly 125 is a unity feedback, moving body hydro-mechanical device. Longitudinal boost assembly 125 comprises a longitudinal boost assembly mount 145 , longitudinal boost assembly input lever 147 hingedly attached to mount 145 , longitudinal boost assembly output lever 149 also hingedly attached to mount 145 , longitudinal boost assembly adjustable hard stops 151 , longitudinal boost assembly hydraulic unit 153 , and longitudinal direct link 155 . Hard stops 151 are adjusted to contact input lever 147 and output lever 149 before over-travel of CCS 111 components occurs. Hydraulic unit 153 comprises a hinged portion 157 hingedly attached to mount 145 and a translating portion 159 attached to hinged portion 157 such that translating portion 159 may translate along hinged portion 157 . Translating portion 159 is also hingedly attached to output lever 149 . Hinged portion 157 is connected to input lever 147 with direct link 155 which is connected to a piston locking bar 181 (discussed infra) for actuating a control piston 179 (discussed infra) such that if input lever 147 is moved toward hydraulic unit 153 , direct link 155 moves locking bar 181 to actuate hydraulic unit 153 in a manner causing translating portion 159 to translate along hinged portion 157 in the direction of movement supplied by input lever 147 . Similarly if input lever 147 is moved away from hydraulic unit 153 , direct link 155 moves locking bar 181 to actuate hydraulic unit 153 in a manner causing translating portion 159 to translate along hinged portion 157 in the direction of movement supplied by input lever 147 . Of course as translating portion 159 moves, output lever 149 also moves in a manner dictated by the geometry of interconnection of the two elements.
Referring now to FIGS. 8-11 , the preferred embodiment of lateral boost assembly 123 is illustrated. Assembly 123 is a unity feedback, moving body hydro-mechanical device. Lateral boost assembly 123 comprises a lateral boost assembly mount 161 , lateral boost assembly input lever 163 hingedly attached to mount 161 , lateral boost assembly output lever 165 also hingedly attached to mount 161 , lateral boost assembly adjustable hard stops 167 , lateral boost assembly hydraulic unit 169 , and lateral direct link 171 . Hard stops 167 are adjusted to contact input lever 163 and output lever 165 before over-travel of CCS 111 components occurs. Hydraulic unit 169 comprises a hinged portion 173 hingedly attached to mount 161 and a translating portion 175 attached to hinged portion 173 such that translating portion 175 may translate along hinged portion 173 . Translating portion 175 is also hingedly attached to output lever 165 . Hinged portion 173 is connected to input lever 163 with direct link 171 which is connected to a piston locking bar 181 (discussed infra) for actuating a control piston 179 (discussed infra) of such that if input lever 163 is moved toward hydraulic unit 169 , direct link 171 moves locking bar 181 to actuate hydraulic unit 169 in a manner causing translating portion 175 to translate along hinged portion 173 in the direction of movement supplied by input lever 163 . Similarly if input lever 163 is moved away from hydraulic unit 169 , direct link 171 moves locking bar 181 to actuate hydraulic unit 169 in a manner causing translating portion 175 to translate along hinged portion 173 in the direction of movement supplied by input lever 163 . Of course as translating portion 175 moves, output lever 165 also moves in a manner dictated by the geometry of interconnection of the two elements.
Both hydraulic units 153 , 167 are powered by a single hydraulic system (not shown). Assemblies 123 , 125 integrate features which minimize impacts to CCS mechanical characteristics even in the event of loss of hydraulic supply pressure failure. For example, to maintain aircraft control when supply pressure is lost, pressure-operated bypass locking valves (not shown) release internal actuator pins 179 to a non-pressure assisted position which subsequently allows control pistons 179 to extend from translating portions 159 , 175 . When extended from translating portions 159 , 175 , pistons 179 are engaged with locking bars 181 , thereby precluding freeplay movement of system elements due to internal valve travel. Also, fluid flow between multiple internal cylinders is allowed while the input levers 147 , 163 are fixed to translating portions 159 , 175 , respectively, such that instead of introducing freeplay into CCS 111 , hydraulic units 153 , 169 merely act as viscous dampers. Further, to prevent overloading of the elements of downstream portion 115 , hydraulic units 153 , 169 incorporate dual concentric main control valves that port hydraulic pressure to return channels before stops 151 , 167 contact the respective input and output levers. This function disables the hydraulic unit 153 , 169 output just prior to the pilot being able to transmit more load to the elements of CSS 111 than the elements are structurally designed to withstand.
It is apparent that an invention with significant advantages has been described and illustrated. Although the present invention is shown in a limited number of forms, it is not limited to just these forms, but is amenable to various changes and modifications without departing from the spirit thereof. | A mechanical flight control system for a rotary-wing aircraft is disclosed. The flight control system comprises an upstream portion, a downstream portion, and a booster means for connecting the upstream portion to the downstream portion. The booster means may comprise dual concentric valve actuators and/or a variety of system load limiting features. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a windshield wiper device, particularly for a motor vehicle.
Numerous windshield wiper devices for motor vehicles having a wiper bearing supporting a wiper shaft, which can be displaced in relation to the wiper bearing by the effects of an axial force component, are known.
For example, a windshield wiper device is known from DE-A-198 51 816 in which the wiper shaft has a radial undercut, in which a securing device sits for axially fixing the wiper shaft in the wiper bearing. This securing device can be displaced by the effects of a defined axial force component on the wiper shaft, whereby the wiper shaft can be displaced in relation to the wiper bearing. This type of axial force component can be caused for example by a pedestrian impacting the wiper shafts of the motor vehicle during an accident. In this case, the wiper shafts recede and disappear within the body of the vehicle thereby reducing the risk of injury to the pedestrian. However, the embodiment shown there is expensive and cost-intensive and therefore only suitable in a limited way for reasonably priced motor vehicles.
SUMMARY OF THE INVENTION
The advantage of the windshield wiper device in accordance with the invention is that it makes a simple realization of pedestrian impact protection possible, which is also cost-effective and allows precise adjustment of the axial force component required for the wiper shaft to recede. This is achieved by a securing device that has a bushing section with an indentation, which engages in the undercut of the wiper shaft.
It is particularly advantageous if the undercut is embodied to be radially circumferential. As a result, the undercut can be made in a simple manner when machining the wiper shaft and a further processing step in manufacturing the undercut is spared.
The axial force component can be adjusted especially precisely via a tub-shaped embodiment of the undercut.
If the indentation in the bushing section of the securing device is embodied to be radially circumferential, the securing device can also be manufactured in a very simple manner and placed on the wiper shaft without having to consider the radial position.
In this case, it is especially advantageous if the indentation is embodied to be tub-shaped in cross section in order to carry out a precise adjustment of the required axial force component.
Ideally, a flange section that is effectively connected to the wiper bearing is attached to the bushing section. As a result, the axial force component acting in the case of a pedestrian impact can be optimally transmitted to the securing device since a large surface of the securing device is supported on the wiper bearing.
The wiper bearing can be protected from dirt and moisture by a bushing-shaped closure section, which is attached to the flange section, making it possible to dispense with an additional closure element for the wiper bearing.
Especially simple and cost-effective manufacturing of the securing device can be achieved by a structure of the securing device that is essentially rotationally symmetrical and essentially S-shaped in cross section.
It is especially advantageous if the rotationally symmetrical securing device has a radial gap. The securing device can bend open via this gap so that even small required force components can be realized.
The securing device can be embodied simply and cost-effectively as a punched bent part made of sheet metal.
In addition, the embodiment of the securing device of fiber reinforced plastic is especially advantageous.
BRIEF DESCRIPTION OF THE DRAWINGS
One exemplary embodiment of the invention is depicted in the drawings and explained in greater detail in the following description.
The drawings show:
FIG. 1 A schematic depiction of a windshield wiper device in accordance with the invention
FIG. 2 A partial sectional representation of a wiper bearing of a windshield wiper device in accordance with the invention
FIG. 3 A detail of an undercut in the wiper shaft with the securing device
DETAILED DESCRIPTION
FIG. 1 shows a schematic representation of a windshield wiper device 10 in accordance with the invention. It is comprised essentially of a support tube 11 on which a wiper motor 12 is fastened. The support tube 11 has two ends on each of which a wiper bearing 14 is arranged.
The wiper bearing 14 is comprised essentially of a tubular section 15 , which is penetrated by a wiper shaft 16 . The wiper shaft 16 itself is connected in a rotationally secured manner at one end to a driving crank 18 , which is connected via a thrust rod (not shown for the sake of clarity) to an output crank 20 being driven by the wiper motor 12 .
In operation, the output crank 20 executes rotational or back-and-forth movement, whereby the driving crank 18 and therefore the wiper shaft 16 are put into a pendulum movement via the thrust rod.
FIG. 2 shows a partial sectional representation of the wiper bearing 14 with the wiper shaft 16 . The wiper bearing 14 is comprised essentially of the tubular section 15 , which is penetrated by the wiper shaft 16 . A fastening section 22 is arranged on the tubular section 15 , which is used to fasten the windshield wiper device 10 to the motor vehicle.
The fastening section 22 is essentially embodied as a flat plate, which is arranged essentially perpendicular to the axis formed by the wiper shaft. An opening 23 is provided in the plate of the fastening section 22 , and this opening is used to accommodate fastening means such as screws or rivets for example. The fastening section 22 is also provided with a circumferential side wall 24 for reinforcing purposes, which extends in a collar-like manner starting from the edge of the flat plate.
Arranged on the side of the tubular section 15 facing radially away from the fastening section 22 is a fastening connecting piece 26 , which has an essentially cylindrical form and extends to the outside approximately perpendicular to the axis formed by the wiper shaft 16 . This fastening connecting piece 26 is used to fastening the wiper bearing 14 to the support tube 11 and features corresponding fastening elements 28 for this purpose so that the fastening connecting piece 26 can be crimped with the support tube 11 . However, in a variation, the wiper bearing 14 can also be embodied as a one-part piece with the support tube 11 .
The wiper shaft 16 has two ends 30 , 34 , which project from the tubular section of the wiper bearing 14 . On the first free end 30 , a cone and a thread are provided as holding elements 32 , on which a wiper arm (not shown here for reasons of clarity) can be fastened. The driving crank 18 is connected to the other end 34 of the wiper shaft 16 in a rotationally secured manner. This driving crank is comprised essentially of a longish crank plate 36 , which is connected on its one end to the wiper shaft 16 and bears a crank articulated bolt 38 on its other end, which is provided for connection to the thrust rod.
Sitting on the wiper shaft 16 is the securing device 40 , which essentially has three sections 42 , 44 , 46 , namely a bushing section 42 , to which a flange section 44 is attached, via which the wiper shaft 16 is supported axially on the tubular section 15 of the wiper bearing 14 . Attached in turn to this flange section 44 is a closure section 46 . The wiper shaft 16 and the securing device 40 are shown here in cross section.
The wiper shaft 16 has an undercut 48 near the tubular section 15 , which is embodied to be tub-shaped and radially circumferential. The securing device 40 correspondingly has an indentation 50 in its bushing section 42 , which is positively engaged with the undercut 48 .
The indentation 50 in the securing device 40 can already be provided during manufacturing and the securing device 40 can be slid with force on the wiper shaft 16 until the indentation 50 engages in the undercut 48 . In one variation, it is also possible to slide the securing device 40 without the indentation 50 on the wiper shaft 16 and then press the indentation 50 into the undercut 48 with an external effect of force.
FIG. 3 shows a detail of the indentation 50 of the securing device 40 and the undercut 48 of the wiper shaft 16 . The undercut 48 is embodied to be tub-shaped and as a result, has a base surface 52 and a side surface 54 inclined thereto by an angle of approximate 45°, and this side surface faces the free end 30 of the wiper shaft. An angle of 90° can also be provided on the side surface 54 facing away from the free end 30 since in the case of a pedestrian impact, the defined axial force component acts on the free end 30 so that the securing device 40 is pushed in the direction of the free end. Because of the inclination of the side surface 54 facing the free end 30 , the securing device 40 then glides on a slanted plane in the direction of the free end 30 . In a variation, the base surface 52 , for example, can also be dispensed with and a V-shaped undercut 48 can be provided. In another variation, this undercut 48 can also have diagonal side surface 54 facing the free end 30 , which side surface turns directly into the other side surface 54 facing away from the free end 30 , whereby a slant is provided for the side surface facing the free end 30 and an angle of 90° is provided for the side surface that faces away.
In a further variation, the undercut 48 is not embodied to be circumferential, but as a recess, whereby the indentation 50 of the securing device 40 , or more precisely of the bushing section 42 of the securing device 40 , is correspondingly embodied. In this case, only a quasi-punctual instead of a circumferential indention 50 is provided.
Of course, these possibilities can also be combined. In this case, although the undercut 48 would be embodied to be circumferential, the indentation 50 of the securing device 40 would be arranged only punctually however.
The wiper bearing 14 is manufactured as one-part with the tubular section 15 , the fastening section 22 and the fastening connecting piece 26 in a plastic injection molding process.
The securing device 40 is embodied as a simple punched bent part made of sheet metal. In one variation, this part can be manufactured, however, of plastic or fiber reinforced plastic or another material such as ceramic.
In operation, the flange section 44 is placed directly on the front side of the tubular section 15 facing the free end 30 of the wiper shaft 16 . One or more stop disks can be provided between the flange section 44 and the tubular section 15 .
The closure section 46 is formed to be bushing-like and grips over the end of the tubular section 15 of the wiper bearing 14 in a cover-like manner. Sealing elements can also be provided here in a supplementary manner to protect the wiper bearing 14 from penetrating water and dirt. | A windshield wiper device ( 10 ), particularly for a motor vehicle, is proposed. This windshield wiper device comprises a wiper bearing ( 14 ) supporting a wiper shaft ( 16 ), which has an undercut ( 48 ) in which a securing device ( 40 ) for axially fixing the wiper shaft ( 16 ) in the wiper bearing ( 14 ) is arranged. The securing device ( 40 ) can be displaced by the effects of a defined axial force component (F) on the wiper shaft ( 16 ), whereby the wiper shaft ( 16 ) can be displaced in relationship to the wiper bearing ( 14 ). According to the invention, the securing device ( 40 ) comprises a bushing section ( 42 ) with an indentation ( 50 ), which engages in the undercut ( 48 ) of the wiper shaft ( 16 ). | 8 |
[0001] This application claims priority of provisional patent application serial No. 60/270,389 filed on Feb. 21, 2001.
FIELD OF THE INVENTION
[0002] The present invention relates to the garment rental business. More particularly it relates to a system and method of streamlining the cleaning, sorting and return process of a uniform rental operation.
BACKGROUND OF THE INVENTION
[0003] The uniform rental business is a substantial industry that provides a product and service for many companies that use uniforms. Restaurants, manufacturing companies, research or analysis laboratories, repair service companies and a wide variety of other companies are among those companies that require some or all of their employees to ware a uniform for safety, image or any number of other reasons. Many companies pay for the cost of the uniforms or special garments they require their employees to wear. For companies that do supply the uniform or garments for their employees the almost universal practice is to contract with a company that specializes in the uniform rental business. Such companies not only supply the necessary uniforms made and designed pursuant to the specifications of the employer but they also periodically pick up the soiled uniforms from the employer, clean the uniforms and return them to the employer on a periodic basis, such as every week etc. A profitable uniform rental business requires a substantial operation that handles a large number of customers (companies that require employees to wear uniforms) to be profitable. Generally, the customers are located over a fairly wide geographical area that requires multiple pick up and delivery routes. Additionally, each customer can have from several to hundreds of employees (wearers) who must wear the required uniform.
[0004] [0004]FIG. 1 is a schematic diagram that depicts the current state of the art in use in the uniform rental business for the process of cleaning and returning rental uniforms to customers. In the current practice companies that rent and clean a large number of uniforms or work related garments for various customers combined all of the garments together from various sources, i.e., customers and routes, and clean them together upon their arrival from the various routes 23 . The dirty garments, when they first arrive, are sorted, generally according to type of textile and dirt or soiling the garments had on them 25 . The purpose for doing this is to wash the garments according to the type of textile and soil or dirt the garment has on it. This is due to the fact that the type of soil or dirt on the garment may dictate the type of cleaning process necessary.
[0005] After the garments were cleaned, they then were sent on to the “tunnel or presses” 27 for a drying and finishing process. In the tunnel the garments are dried by heat and blown air in such a fashion that most the wrinkles fall out of the garments. Upon leaving the tunnel or presses the garments are then sent through a two-step sorting process (some times three steps) to reassemble the garments by routes and customers on each route for redelivery to the customer. This process generally takes two days, a day being needed for each sorting step. The first sorting step 31 involves sorting the garments according to their routes. Each garment will typically have a tag, not shown, which identifies the customer and wearer from which the route can be determined. The tag can alternatively have the route identification on it. At the first sort stage a person will usually visually inspect the tag 33 and then place it in the rack of the correct route 35 . At the second sort step 37 each routes garments are then be sorted according to customers on that route and wearers at each customer. Some operations might break the second sort into a second sort by customer on each route and then a third sort by wearer at each customer.
[0006] Whether this two or three step sorting process is done by hand or is partially or fully automated using bar codes, radio frequency identification tags on the garments or some other identification system, the process is expensive and time consuming. In fact such a process can add up to a day or more to the cleaning and return process.
[0007] Thus, what is needed is a system and method for streamlining the sorting and returning process for the uniform rental business; a system that can be implemented within the context of a wide variety of current uniform rental cleaning and return operations without the need for expensive equipment upgrades or new equipment.
SUMMARY
[0008] It is an object of the present invention to provide an efficient and expeditious method for a commercial laundry operation to clean rented uniforms or work related garments for a large number of customers. It is a further object of the present invention to provide a method that can be easily integrated into the operation of a commercial laundry or uniform rental operation in an efficient, timely and cost effective manner.
[0009] The present invention accomplishes these and other objectives by providing a method for sorting and sequencing of garments in a just in time flow (no buffer or backlog allowed) from a multitude of sources, located on a plurality of routes, for cleaning and return to the original source of each specific garment colleted, the method having the steps of: collecting a multitude of garments from a multitude of sources along a plurality of routes; cleaning the garments while retaining them in identifiable collections; putting the garments through a drying process sequenced according to their specific routes; sorting each routes garments by customer and wearer upon completion of the drying process; and wherein since the integrity of an identifiable group of garments from each specific route has been maintained all of the garments from a specific route can be quickly reassembled according to their specific route at any point during the process and thereby eliminate the need for sorting individual garments on a route by route basis.
[0010] In a further aspect of this invention it provides a method with the additional steps of sorting the garments according to type of soil on each garment for a cleaning process designed to clean that type of soil from the garment; segregating into retained identifiable collections during the sorting step garments from each specific route for cleaning according to type of soil; and cleaning according to type of soil the garments from several different routes together in their retained identifiable collections by route so that garments form each of the routes do not become mixed with garments from other routes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention will be better understood by an examination of the following description, together with the accompanying drawings, in which:
[0012] [0012]FIG. 1 is a schematic diagram of a prior art uniform rental cleaning, sorting and return operation;
[0013] [0013]FIG. 2 is a schematic diagram of a uniform rental cleaning, sorting and return operation according to a preferred embodiment of the present invention; and
[0014] [0014]FIG. 3 is flow chart of the process of a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] In a uniform rental business according to the present invention a driver delivers clean garments to various customers and picks up dirty garments on a periodic schedule. Usually, the routes are step up so that each customer is visited once each week, generally on the same day, by a driver for the exchange of clean garments for dirty garments. A route will be made up of several customers, on average 35. Each customer will be made up of several wearers, depending on the size of the customer, for a small company this could be less than ten wearers on the other hand for a large customer this could be several hundred wearers. Each identified wearer might have 11 shirts and pants. Each garment would have an identification tag with information such as customer number and/or name, wearer number and/or name, or any other information deemed necessary to facilitate the pick up, cleaning, sorting and delivery of clean garments back to the customer. The tags, in the preferred embodiment would have the information in human readable form as well as some type of coding system such as a bar code etc. that is machine-readable, i.e. optical scanner the can read bar code etc.
[0016] The system of present invention provides for the washing of the garments route by route as they arrive and keeps the garments from a specific route together as they come out of the washroom and into the Tunnel or the presses after the cleaning process. The Tunnel puts the garments thorough a combined heat and blow dry drying process designed to dry and remove wrinkles from the garments. Upon leaving the Tunnel or the presses the garments are sorted by customer and wearer at the same time. Damaged garments are then mended and the garments are assembled for delivery by route. The whole process can take only a matter of hours. The system can also accommodate the inclusion of late garments.
[0017] [0017]FIG. 2 is a schematic diagram of the process of the present invention. Upon arrival at the cleaning plant 51 , the garments in a preferred embodiment are sorted according to textile and soil or dirt for the purpose of washing 53 . However, garments from the same route are kept together and segregated from the garments of another route. Ideally the garments from one route are cleaned together in the same washing process. If the type of textile requires a separate type of cleaning process, garments from the same route that require the specific cleaning process, are placed in a special mesh bag that allows the cleaning liquid to flow through the bag and wash the garments in the bag but keeps the contents of the bag together. Thus, garments from several routes can be cleaned together in the same cleaning process without losing the integrity of their groupings by their routes.
[0018] Once the cleaning process is complete the garments grouped together with their particular route are then sent through the “Tunnel or the presses” 58 . The process in the Tunnel 58 as noted above dries and helps remove wrinkles from the garments. Upon reaching the end of tunnel the garments arrive at the hanging station 60 . The garments arrive at hanging station 60 grouped in their routes.
[0019] From the hanging station they move by conveyor 63 onto the sorting area 65 where the garments are sorted by customer number and wearer number of each customer. This is possible since the garments are already grouped together by their respective routes. Sorting of the garments in the preferred embodiment is done, in a just in time flow, by customer numbers 67 instead of route number since they are already segregated into their respective routes. The sorting area ( 65 ) is not use as a storage area anymore, but rather as a processing station in which the garments pass rapidly through, as in they do in the tunnel.
[0020] From the sorting station the garments move onto a final inspection station 73 and a bar code station 73 , and optional step. At this stage damaged garments in need mending 77 are fixed. At the bar code station the orders are reviewed to determine if they are in proper order.
[0021] In the system of the present invention completing the passage from the hanging station 60 to the sorting area can take less than 45 minutes per route. Similarly passage through the sorting area can take no more than 45 minutes. Finally, passage through the final inspection station can take no more than 45 minutes and thus the garments sorted and packaged by each route arrive at the final loading station 81 in no more than 2 hours and 15 minutes after leaving the tunnel. This results in a much more efficient operation than allowed by existing practices which require an initial sorting of the garments by route.
[0022] A flow chart of the major operational steps of the present invention is set forth in FIG. 3. The soiled garments arrival grouped together by routes, this is due to the fact that they arrive at the cleaning plant on each respective routes pickup truck. However, the garments from each route are kept together in their respective routes grouping. The soiled garments are then inspected by the drivers to determine if they need special cleaning procedures 101 . The garments move into the system grouped together by their routes 103 . When the garments are washed they are washed so that the integrity of the grouping of the garments by route is maintained 105 . The integrity of the grouping of the garments by route can be maintained by washing the garments from one route together as in their own batches. If special washing procedures are required for some of the garments from a route they can be washed with garments from another route by placing the garments from each route in their own mesh bag (a mesh type of garment bag that allows the cleaning fluid to freely mix with the garments during the cleaning process but yet retains the garments in retained identifiable collections for each route cleaned together). Upon completion of the washing stage the garments are sent through the Tunnel sequentially together with the other garments from the same route 107 . The next step is sorting each route's garments by customer and wearer at each customer 109 . The garments are then inspected to determine if mending is necessary and to assure the garments are in the correct order 111 . The next step is confirming each route's garments have been washed, have not been lost and are ready for return to each customer and confirming this by an appropriate database entry 113 . This step of verifying that a customer's garments are accounted for and clean is of particular importance from the customer service point of view. In a preferred embodiment entry of the information into a database would be accomplished by an automatic data entry system such as one that uses bar codes and laser readers as discussed above. Naturally, a computer system with appropriate software and database would be used. Such information would facilitate billing of customers. The final step is return of the clean garments to each customer by route 114 .
[0023] Elimination of the one or two extra steps currently in use in conventional methods is quite significant whether or not the system is fully or partially automated or simply done manually. Naturally, if it is a wholly manual operation eliminating the step eliminates a significant labor overhead cost. Also, in a fully or semi-automated system elimination of the step not only eliminates costly machinery required for the additional sorting step it also eliminates the need to repair such machinery. Since the system and method of the present invention substantially reduces they complexity of the operation and presents a large space saving, it can be more easily integrated into current operations with a minimal investment and without the need for costly changes to existing plant and equipment.
[0024] As noted above the present invention saves time since it highly efficient and allows the completion of the cleaning and sorting process to a day at most. If the operation is working on a one-week cycle, i.e. clean uniforms are delivered and dirty ones picked up every week from each customer than the work cleaning and sorting of the garments for delivery back to the customer is accomplished at least four working days in advance of the delivery date. Since the system is simpler to operate it is much easier to supervise operation and control the workflow. Also, by simplifying the operation with the present invention the chances of problems, such as lost garments etc. are substantially reduced. All of these advantages add up to better customer satisfaction.
[0025] While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and detail may be made to it without departing from the spirit and scope of the invention. | A method for organizing the picking up of soiled garments, cleaning them and returning of them to a customer is disclosed that greatly improves the efficiency and speed of current methods by retaining the garments of a specific route together in an identifiable collection and working in a just in time flow. Upon the arrival of the soiled garments at the cleaning plant, garments from each route are cleaned and dried in identifiable collections according to the route on which the garments were picked up. The garments are then sorted by customer on each route and wearer at each customer at which point the garments are ready for return to the customer. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
None.
FIELD OF THE INVENTION
This present invention relates to hinges for use in furniture, preferably cabinetry.
BACKGROUND OF THE INVENTION
Embodiments of the invention disclosed herein include a hinge mounted at one end to a frame of an article of furniture and at another end to a door. An integrated hinge locking mechanism allows ease of installation and removal of a door at the place of manufacture or on the job site.
In furniture construction two types of cabinet construction are common, face-frame and frameless. Frameless cabinets have a case upon which the door hinges are mounted directly. In face-frame construction a frame, wider than the edge of the case, is attached to the front of the cabinet case.
Face-frame construction allows for a sturdier mounting surface for the door hinges and better support for the door. A face-frame construction will also allow the case to better resist warping and remain square during transportation and installation.
Cabinet construction presents some unique design considerations. Alignment of the doors is paramount to maximize visual and functional effects. In frameless cabinets, a door in a closed position will reveal little of the cabinet case. In face-frame construction a frame, wider than the case, is attached to the front of the cabinet case. The amount of the frame that a door will cover in face-frame construction is called the overlay. Face-frame construction allows the frame, rather than the case, to show because the door does not cover the whole frame surface. Misalignments may be more visible on face-frame construction. Thus it is important that the doors are adjusted properly especially in large overlay, high end cabinets.
Existing face-frame hinges offer different degrees of adjustability to accommodate alignment. However correct alignment and adjustment sometimes necessitates removal of the door from the cabinet frame. It is also desirable at times to align and adjust the doors offsite and remove them for transport to the job site. There are also a variety of reasons for removing and reinstalling the doors before or after alignment. Removal of the doors for cabinet finishing onsite is necessary in many applications. Therefore a face-frame hinge must offer several options for adjustment, be as compact and lightweight as possible to maximize effectiveness, and also allow quick and efficient removal and installation of the doors.
SUMMARY OF THE INVENTION
An object of the invention is to provide a face-frame hinge that makes it easier to mount a door to a frame, adjust the hinge arm and therefore the door with respect to the frame, and remove a door from the frame.
In all embodiments of the invention a mounting and adjustment assembly is utilized to mount the hinge and door to the face-frame of an article of furniture. The mounting and adjustment assembly allows adjustment of a door along the horizontal and vertical axes. An upper plate is used to connect the door to the mounting and adjustment assembly. An adjustment mechanism on the upper plate allows adjustment along a third axis approximately orthogonal to the first two axes.
A locking mechanism on the upper plate provides a method for quick and efficient installation and removal of the door. The locking mechanism shown and described herein is an integrated, spring-actuated pivot lever although other locking mechanisms are contemplated.
Modern cabinetry and storage furniture is most functional when there is easy access to the interior storage area. The challenge to hinge manufacturers is to design a compact hinge that maximizes the effective opening to allow the greatest access to the interior storage portion of the cabinet. The mounting and adjustment assemblies disclosed herein are compact by design to allow maximum access to the cabinet interior. The locking mechanisms described are also designed to minimize the projection of the hinge into the cabinet or furniture opening.
Embodiments of the invention are more closely described on the basis of drawing representations contained herein. Further characteristics, advantages and uses of embodiments of the invention result from the drawings and the descriptions that follow.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of the hinge components attached to a cabinet door and cabinet frame.
FIG. 2 is an exploded view of the components of the mounting and adjustment assembly.
FIG. 3 is a perspective view of the mounting and adjustment assembled attached to the face-frame of a cabinet.
FIGS. 4A through 4D illustrates the steps of attaching the upper plate and hinge arm to the mounting and adjustment assembly.
FIG. 5 is a perspective view of another embodiment of a mounting and adjustment assembly and upper plate and arm.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows components of a preferred embodiment of the invention attached to a cabinet door 10 and cabinet frame 11 . The frame is connected to the front of the cabinet case 13 . The mounting and adjustment assembly 16 is connected to the inner side wall 14 of a vertical component of the face-frame 12 . The hinge cup 18 , arm member 20 , and upper plate 22 are connected to the cabinet door. The pivot lever 24 on the upper plate is used to lock the upper plate in place after it is attached to the mounting and adjustment assembly. The pivot lever is typically spring actuated (spring not illustrated). A shoulder screw 26 is used to allow further movement of the hinge and door with respect to the mounting and adjustment assembly.
The frame 11 is comprised of two vertical components 12 and two horizontal components 15 that form a rectangular structure. The opening or access into the interior is defined by four frame inner walls (only inner walls 14 and 17 are shown). As can be seen, face-frame construction reduces the access to the interior therefore hinge components must be compact so they do not further reduce access.
FIG. 2 shows the individual components of the mounting and adjustment assembly. The connecting plate 28 is moveably attached to the adjustment plate 30 . The adjustment plate is moveably attached to the mounting or base plate 32 . The connecting plate, adjustment plate, and the mounting plate are attached before the mounting and adjustment assembly is secured to the cabinet face-frame.
The first adjustment mechanism 34 allows the connecting plate 28 to move in two directions along the z-axis (see coordinate orientation) in relation to the adjustment and mounting plates and cabinet frame. The first adjustment mechanism illustrated in FIG. 2 is sometimes referred to as a cam device or eccentric. In the FIG. 2 embodiment, portions of the sides 36 of the connecting plate dovetail into mating sections 38 of the adjustment plate. These dovetailed, beveled surfaces allow more precise movement of a plate with respect to an adjacent plate.
The second adjustment mechanism 40 allows both the connecting plate and adjustment plate to move in two directions along the y-axis in relation to the mounting plate and cabinet frame. Thus, the mounting and adjustment assembly allows four directions of movement. Mating dovetailed sections on the base plate 42 and the adjustment plate 44 allow the movement controlled by the second adjustment mechanism (cam, screw or eccentric).
The connecting plate pin 46 is utilized by the upper plate for connection purposes. The bridge 48 and bridge slot 50 are utilized in conjunction with the shoulder screw to aid in connecting the upper plate to the mounting and adjustment assembly.
The complete mounting and adjustment assembly 16 is shown attached to an inner side wall of the cabinet face-frame in FIG. 3 . The pin 46 is shown affixed to the connecting plate. The pin is typically connected to the upper plate by swaging. Swaging is a metal-forming technique in which the metal or a portion of a metal component is plastically deformed to its final shape using high pressures, either by pressing or hammering, or by forcing through a die. The ends of the pin here can be swaged to hold the pin in place within the connecting plate.
FIGS. 4A through 4D presents top views illustrating the sequence of attaching the upper plate and arm to the mounting and adjustment assembly. These components are shown unattached to the cabinet door and frame for clarity.
FIG. 4A shows the relative alignment orientations for the connecting components of the upper plate and the mounting and adjustment assembly. The shoulder 52 and recess 54 of shoulder screw 26 are utilized to help affix the upper plate 22 to the mounting and adjustment assembly 16 .
The shoulder 52 is first aligned with the slot in the bridge 48 of the connecting plate as illustrated in FIG. 4B . The shoulder screw is then fully positioned in the bridge slot and the pin 46 is aligned with the upper plate positioning slot 56 as seen in FIG. 4C . As the slot of upper plate is further engaged by the pin, the leading edge 58 of head of the pivot lever is in contact with the catch 60 on the mounting and adjustment assembly. The pivot lever begins to rotate as the upper plate is fastened to the mounting and adjustment assembly. The catch on the mounting and adjustment assembly is typically part of the connecting plate.
The pivot lever contains an internal spring 25 shown in FIG. 4A which biases the lever into a locked position when the leading edge 58 clears the catch 60 . When the upper plate is fully fastened as shown in FIG. 4D , the head of the pivot lever is engaged over the catch in locked position 62 . To remove the upper plate, one would merely push gently on the trailing edge 64 of the pivot lever to counter the force of the internal spring and release the upper plate from the locked position.
FIG. 5 shows another embodiment of a mounting and adjustment assembly and upper plate and arm. An embodiment of this nature could accommodate a door that provides a bigger overlay. In this embodiment the bridge 68 on the connecting plate does not have a slot because there is no shoulder screw on the upper plate. The end of the bridge 68 actually engages in a bridge positioning slot 70 on the upper plate. The upper plate would be attached to the mounting and adjustment assembly by first aligning and inserting the end of the bridge 68 into the bridge position slot 70 on the upper plate. The upper plate can then be fastened into a locked position in the manner described with the previous embodiment.
Adjustments on the mounting and adjustment assembly in both embodiments illustrated offer movement of the cabinet door in the horizontal (z) and vertical (y) directions. Embodiments of the present invention also allow movement of the cabinet door approximately along the x-axis. This adjustment is useful whether one or two doors are mounted on a face-frame cabinet. The spacing between the adjacent surfaces of the two doors is critical to appearance and function. The x-axis adjustment can be utilized to alleviate uneven spacing between two doors mounted on a cabinet face-frame.
The upper plate 22 shown in the FIG. 1 embodiment has an adjusting shoulder screw 26 that provides for movement of a cabinet door approximately along the x-axis. This movement approximately along the x-axis is relative to the cabinet door being in a closed position.
The adjusting mechanism for movement approximately along the x-axis is positioned on a bracket 72 of the upper plate on the embodiment illustrated in FIG. 5 . This adjustment also allows door movement approximately along the x-axis relative to the cabinet door being in a closed position as previously disclosed.
CONCLUSIONS, OTHER EMBODIMENTS, AND SCOPE OF INVENTION
The three main components of the mounting assembly, the connecting plate, the adjustment plate and the base plate can be interconnected through a variety of manners. In one embodiment, the dovetailed sections are swaged so that the plates can have limited movement with respect to an adjacent plate. Other types of metal forming procedures could be utilized to allow each plate limited movement with respect to the adjacent plate.
The connecting plate pin 46 can also be affixed to the connecting plate by a variety of methods. Either cold or hot metal forming procedures could be utilized effectively.
The pivot lever disclosed herein is spring actuated. An internal spring helps engage the lever into a locked position. Other embodiments could include a pivot lever that does not utilize an internal spring. A cam, latch or screw component could be utilized to hold the lever in a locked position until an operator unlocked the lever. A spring-actuated lever is preferable due to the ease in unlocking the lever and removing the door and attached hinge components from the mounting and adjustment assembly.
The position of the pivot lever on the upper plate also aids in removing the door from the mounting assemblies. An installer can support the door with one hand and quickly flip each pivot lever to remove the door from its mountings.
Other embodiments of a face-frame hinge could have only two adjustment mechanisms as an integral part of the hinge. One example of such an embodiment would be to eliminate the adjustment plate and have a first adjustment on the connecting plate and a second adjustment on the upper plate. In these embodiments, the connecting plate would still be utilized to attach and secure the upper plate to the mounting assembly and frame. The connecting plate could be adjusted along only one axis, i.e., either the z or the y axis. The second adjustment on the upper plate would allow the cup to be adjusted approximately along the x axis. All embodiments would include a locking mechanism attached to the upper plate. Although there would only be one adjustment mechanism integral to the mounting assembly, there could still be adjustment of the assembly along the axis not controlled by the first adjustment mechanism. Adjustment along the axis not affected by the first or second adjustment mechanism could be accomplished through the use of standard screw fitted into a slot in the mounting plate, for example.
In yet another embodiment with a locking mechanism attached to the upper plate, only two adjustment mechanisms would be integral to the hinge. As an example, the third adjustment could be eliminated from the upper plate. Thus, there would only be a first and second adjustment integral to the mounting and adjustment assembly.
When an adjustment mechanism “integral to the hinge” is referenced, this does not include a slot that could accommodate a standard screw attached to the frame. An adjustment mechanism in the context of the embodiments of this invention that is integrated with a hinge must be mounted on a hinge component.
Thus, although there have been described particular embodiments of the present invention of a new and useful device, it is not intended that such references be construed as limitations upon the scope of this invention except as set forth in the following claims. | A hinge for detachably anchoring a door to a frame of a piece of furniture includes a mounting and adjustment assembly mounted on the frame, a hinge cup attached to an arm and upper plate, and a locking mechanism attached to the upper plate. An embodiment of the mounting and adjustment assembly includes a base/mounting plate, an adjustment plate and a connecting plate. An embodiment of the locking mechanism is spring actuated to facilitate installation and removal of the door. | 8 |
This application is a Continuation of prior application Ser. No. 09/875,538 filed Jun. 6, 2001, now ABN incorporated by reference herein, which is a Continuation of prior application Ser. No. 09/223,923 filed Dec. 31, 1998, now ABN incorporated by reference herein.
FIELD OF THE INVENTION
This application relates to telecommunication systems and, more specifically, to a method and apparatus for improving the functionality of a telephone hybrid circuit. The invention provides a means for sensing the communication signal on the bidirectional telephone line pair by incorporating a sense winding in a coupling transformer. Several benefits are provided by the apparatus using the sense winding including an improved signal-to-noise ratio at the receiver output port.
BACKGROUND OF THE INVENTION
A variety of two wire to four wire conversion circuits are used extensively in telecommunication networks. The conversion circuits typically exemplified are hybrid circuits. Hybrid circuits as used herein may also be referred to as analog echo canceller circuits. FIG. 1 is provided to illustrate the functionality of a hybrid circuit.
A hybrid circuit typically has two half-duplex paths, a transmit pair 118 and a receive pair 116 , and a full-duplex bidirectional pair 112 of wires. The bidirectional pair may be, for example, a pair of telephone wires coupled from a customer location to a telephone central office (CO) or other facility. The bidirectional pair serves as a transmission channel for a signal from the customer location to a CO and for a signal from the CO to the customer location. Hence at the CO, where a hybrid circuit is used, the bidirectional pair has a receive signal from the customer location and a transmit signal from the CO. The hybrid circuit provides a means for separating the transmit signal and the receive signal at the CO. Persons working in the telecommunication field would appreciate the hybrid circuit can also be used in data communication equipment at a customer location or elsewhere within telecommunication networks.
Referring again to FIG. 1 there is shown a hybrid circuit. The hybrid circuit, as illustrated, is a four port device having a bidirectional port, a receive port, a transmit port, and a balancing impedance port. The bidirectional port is coupled to a bidirectional channel for bidirectional signal flow, i.e., transmit and receive signals flow on the bidirectional channel. The transmit port is the input for a transmit signal which is coupled by a transmit pair of wires. A portion of the transmit signal is coupled to the bidirectional channel for transmission to a far end location. The receive port is coupled to the bidirectional channel and receives a far end signal which is transmitted from the far end location. The receive port therefore contains a receive signal, where the receive signal is typically an attenuated version of the signal from the far end location. The balancing impedance port is coupled to an impedance approximately equal to the impedance of the bidirectional channel.
An ideal hybrid circuit has no energy transferred from the transmit port to the receive port while maximizing energy from the transmitter to the bidirectional port and from the far end through the bidirectional port to the receiver. A figure of merit called the transhybrid loss is used as a measure of the amount of transmit signal contained in the receive signal. It is also important to consider the efficiency with which the transmit signal is transferred to the bidirectional port, and the receive signal is received from the bidirectional port when evaluating the overall performance of a hybrid circuit.
An example of a conventional hybrid circuit is a passive circuit using specially wound transformers, such as described in Transmission Systems for Communications by Members of the Technical Staff at Bell Telephone Laboratories, 1981. Conventional hybrid circuit designs include circuits with and without transformers and may use summing amplifiers for signal canceling, as opposed to the canceling magnetic flux arrangements of the hybrid cited in the above reference. Still other conventional circuits, such as the one disclosed by Hirohisa in Japanese Patent Publication 06068346, recognize the need to canceling out the effects of internal resistance variations due to temperature variations of the transformer windings.
SUMMARY OF THE INVENTION
One objective of the present invention is to increase the signal-to-noise ratio (SNR) at the output of a receiver. The receive SNR depends upon the amount of far end (desirable) signal appearing at the receiver, as well as the amount of near end (undesirable) signal appearing at the receiver. An increase in SNR will provide a better bit error ratio and can also allow for an increase in transmission distance. In some data communication systems around a one dB increase in SNR will allow for an additional 500 feet of cable between transceivers, i.e., between the near end and far end locations.
Another objective of the present invention is to remove the DC response ambiguity caused by variations of winding resistance in hybrid circuits using transformers. The variations of winding resistance between various transformers of a given kind and with temperature typically causes the transfer function of the hybrid circuit using a transformer to change at low frequencies. Hence there is a need to avoid the DC response ambiguity caused by temperature and component variations.
In some hybrid circuits having transformers it is desirable that the pick-off signal be at a voltage level independent of either the far end voltage or the near end voltage. The circuit of the present invention, having a separate sense winding on the transformer, provides a means for independently adjusting the level of the pick-off signal by adjusting the number of turns in the sense winding.
Another objective of the present invention is to reduce the effects transformer leakage inductance has on the replica transfer function. A reduction in these effects allows a hybrid circuit having a transformer to operate over a wider range of frequencies, thereby providing better hybrid performance. Further, it renders the hybrid circuit relatively insensitive to changes in leakage inductance with different transformers.
Because analog systems in telecommunications systems may operate with a variety of common-mode voltages and power supply voltages, it is sometimes useful to have DC isolation between circuits. The present invention provides a means for providing DC isolation.
The above objectives indicate there is a need for an improved method and apparatus for providing hybrid coupling. Further the apparatus and method should be cost effective and have parameters that may be changed to meet the needs of individual users. A sense winding on a transformer arranged as a coupling element serves to meet the above objectives.
Thus, in accordance with a preferred embodiment of the present invention, an apparatus is provided for canceling a near end signal from a far end signal in a communication system having a bidirectional transmission medium. The apparatus includes: a transformer first winding for conveying the near end signal to the bidirectional transmission medium; a transformer second winding coupled to the first winding and the transmission medium for outputting the near end signal onto the bidirectional transmission medium; and a transformer sense winding galvanically isolated from both the first and second windings but coupled to the bidirectional transmission medium for receiving the far end signal from the bidirectional transmission medium and generating a sense winding output containing energy corresponding to both the near end signal and the far end signal. The apparatus further includes a replica network for generating a replica of the near end signal, and a receiver for combining the sense winding output and the replica to provide a receiver output signal that has a substantially reduced amount of near end energy.
In another aspect of the present invention, a method of providing hybrid functionality is disclosed for a system in which near end and far end signals are transmitted and received on a bidirectional communications medium. The method includes the steps of: transmitting a near end signal on the bidirectional communications medium; receiving, at a transformer sense winding having an independently selectable number of turns and an independently selectable DC bias voltage, the far end signal from the bidirectional communications medium; providing, from the sense winding to a receiver, a sense winding output signal having energy corresponding to both the near end and far end signals; generating a replica of the near end signal; providing the replica to the receiver; and combining, at the receiver, the sense winding output signal and the replica to generate a receiver output signal that has a substantially reduced amount of transmit energy.
BRIEF DESCRIPTION OF THE DRAWINGS
For a complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numbers indicate like features and wherein:
FIG. 1 illustrates a hybrid circuit used for two wire to four wire couplings in telecommunication networks;
FIG. 2 is a prior art analog echo canceller circuit having a transformer coupling;
FIG. 3 is an analog echo canceller circuit having a transformer with a sense winding in accordance with the present invention;
FIG. 4 is a detailed illustration of an embodiment of the present invention;
FIG. 5 is a flow chart illustrating the method of the present invention; and
FIG. 6 is an embodiment of the present invention incorporating balanced circuits.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An arrangement of elements for a four wire to two wire coupling for telecommunications signals is shown in FIG. 1 . The block diagram of FIG. 1 shows a hybrid circuit 110 having a full-duplex bidirectional signal port 112 which is used to transfer information in two directions. A half-duplex transmit port 118 of the hybrid circuit couples a transmit signal from transmitter 120 . A far end signal is coupled to a half-duplex receive port 116 and conditioned by a receiver 130 . An impedance balancing port 114 of the hybrid couples a balancing network 140 to the hybrid circuit 110 and is typically considered part of the hybrid circuit. The hybrid circuit of FIG. 1 is used in a variety of locations in a telecommunication network, familiar to those skilled in the telecommunications arts.
A prior art hybrid circuit 200 as shown in FIG. 2 provides the functionality as shown in the block diagram of FIG. 1 . As shown in FIG. 2, a transmitter 280 includes a single-ended line driver or transmit amplifier 210 for converting a transmit signal to a near end voltage (V NE ). The near end voltage (V NE ) represents a near end signal which can be, for example, a voice signal, a data signal or other telecommunication signal. The near end voltage couples energy through source impedance (Z S ) 212 to a transformer 240 . The transformer receives the near end energy at a first winding (W 1 ) 242 and couples the energy to a second winding (W 2 ) 246 allowing near end energy to flow in the full-duplex bidirectional path 250 .
Signals from the far end are coupled from the full-duplex path 250 through transformer 240 and presented to a receiver 290 , which-includes a single-ended receive amplifier 230 having an inverting input 234 . A far end voltage (V FE ) at the second winding 246 of the transformer, represents the far end signal. A pick-off node 217 , where the far end signal is picked-off, is the junction of source impedance (Z S ) 212 and first winding of the transformer 242 . The cable impedance (Z C ) 260 is the impedance of the bidirectional channel seen looking towards the source of the far end signal.
As further shown in FIG. 2, the pick-off node 217 has a pick-off voltage (V PO ). The pick-off voltage (V PO ) is composed of the desired far-end signal, and the undesired near-end signal, i.e., undesired at the receive signal port. To cancel the near-end component of the pick-off voltage (V PO ), a replica voltage (V R ), for example, can be applied to a signal combining device such as the receive amplifier 230 of FIG. 2 . The replica voltage (V R ) is generated by a replica network 218 . The replica network may be, for example, a series arrangement of a source impedance (Z R ) 214 for the replica and a replica impedance (Z WIR ) 216 . Ideally, the replica network transfer function, (V R /V NE ) is equal to the pick-off transfer function (V PO /V NE ). Further, for the ideal case, the near-end signal is completely canceled at the output of receive amplifier 230 and the output serves as the receive signal port.
Note that the presence of a first winding resistance 271 and a second winding resistance 272 in the transformer 240 attenuates the far end signal and increases the near end signal received at the pick-off point. These undesirable effects of winding resistance are reduced by the present invention, as will be seen upon the discussion of FIG. 3 .
FIG. 3 shows an embodiment of the present invention. As discussed with respect to FIG. 2, FIG. 3 includes a source impedance (Z S ) 212 for coupling the near end voltage (V NE ) to the bidirectional path 250 . Similarly, the far end signal (V FE ) is coupled to a sense winding 348 in sense transformer 340 . The pick-off point (V S ) 450 , however, is now the output of the sense winding and thus the pick-off point 217 of FIG. 2 has effectively been moved to inside the transformer 340 . The sense winding 348 , which is galvanically isolated from and magnetically coupled to the first and second windings 342 and 346 , is coupled to the inverting terminal 234 which has a relatively high input impedance. The sense winding pick-off point 450 has more far-end signal and less near-end signal than the pick-off point 217 of the prior art circuit of FIG. 2 . Further, the sense winding 348 has an independently selectable number of turns ratio for optimizing the signal-to-noise ratio of the received far end signal, and is biased at an independently selectable DC voltage so as to allow for compatibility with various types of receiver circuits.
The replica network 318 in FIG. 3, by way of example and not limitation, is shown as comprising a series arrangement of impedances Z SR 314 and Z WSR 316 , wherein Z SR and Z WSR are selected so as to match the transfer functions V R /V NE and V S /V NE .
FIG. 4 is equivalent to FIG. 3, where the sense transformer 340 is replaced by an equivalent T-model. The T-model clearly shows how the pick-off point has moved from the left side of the transformer to the center of the transformer 450 ′, increasing the far-end signal and decreasing the near-end signal at the pick-off point. For example, the windings of the sense transformer are shown with a 1:1 turns ratio. Sense transformers with a variety of turns ratios fall within the scope of the present invention.
The T-model of FIG. 4 further shows leakage inductances L W1 412 and L W2 418 . Once again, the sense winding is used beneficially, this time to mitigate the effect of the leakage inductance. Communications systems are typically configured so that Z S approximately matches the impedance looking into bidirectional cable 250 . Since L W1 and L W2 are approximately equal in most transformers, their contribution to the transfer function V S /V NE is minimized because of numerator and denominator canceling effects.
In summary, the circuit of FIG. 4 provides a means for two wire to four wire coupling. The signal from the transmit amplifier 210 is coupled through the sense transformer 340 to the bidirectional path 250 . The far end signal is coupled to and through the receive amplifier 230 such that the output of the receive amplifier 230 contains a substantially reduced amount of near end energy along with received far end energy. The novel arrangement of elements in FIG. 4 eliminates DC ambiguity since DC signals cannot be coupled through the transformer. Further, the leakage inductance effects on the replica transfer function are significantly reduced when a sense winding serves as a pick-off point. The voltage signal V S across the sense winding 348 , which represents a pick-off voltage closer to the bidirectional transmission medium and which is a scaled representation of the voltage at node 450 ′, is coupled to the inverting input 234 of the receive amplifier 230 . Thus, the voltage signal V S contains more of the far end signal and less of the near end signal, thereby increasing the SNR at the output of the receive amplifier 230 . In addition, since the sense winding may be galvanically isolated from windings W 1 and W 2 , the sense winding can have a different DC voltage or reference voltage from either winding W 1 or W 2 . By contrast, the reference voltage for the receive amplifier in the prior art circuit 200 is always the same as that for the transmit amplifier.
Referring again to FIG. 3, the embodiment of the analog echo canceller circuit shown therein includes a transmitter 280 having a single-ended line driver, i.e., transmit amplifier 210 , and a receiver 290 having a single-ended receive amplifier 230 . Alternatively, the analog echo canceller of the present invention can be constructed and arranged to include a balanced circuit as shown in the preferred embodiment of FIG. 6 . Those skilled in the art would appreciate that the balanced circuit as shown in FIG. 6 typically yields a better signal-to-noise ratio, processes wider signal swings, and rejects distortion and common mode noise better than the single-ended circuit of FIG. 3 .
As shown in FIG. 6, the present embodiment of the analog echo canceller includes a balanced circuit in the transmitter having two matched voltage sources 610 and 612 . The voltage sources 610 and 612 , as shown by example and not limitation, can be coupled across two replica circuits 618 and 620 , which are optionally coupled to a bias node 622 as shown in FIG. 6 . Each replica circuit 618 and 620 is further coupled to corresponding matching source impedances (Z SB ) 614 and 616 , respectively, which are in turn coupled to a first winding 642 of sense transformer 640 . The first winding 642 is in turn coupled to a second winding 646 , which itself is coupled to a bidirectional path 250 . According to the embodiment of FIG. 6, half the near end signal (V NE1 ) is provided by voltage source 610 and half (V NE2 ) by voltage source 612 . Replica signals VR 1 and VR 2 corresponding to V NE1 and V NE2 , respectively, are generated by replica circuits 618 and 620 , respectively.
On the receive side, a far end signal (V FE ) is applied to a sense winding 648 in the sense transformer 640 . The sense winding 648 , which may include a center tap 650 , is galvanically isolated from both the first and second windings 642 and 646 and is coupled to two receive amplifiers 630 and 632 . The center tap 650 of the sense winding 648 may be grounded or biased at an independently selectable DC voltage level V BIAS or left unconnected. As such, the receive amplifiers 630 and 632 each combine the pick-off voltage signal V S , which contains near end energy and far end energy, with replicas from 618 and 620 representing the corresponding near end portions. Each amplifier thus outputs signals V OUT1 and V OUT2 that have substantially reduced amounts of the corresponding near end signals V NE1 and V NE2 .
As for further details of the circuit of FIG. 6, those skilled in the art would appreciate that values for the components, gain settings, and other design parameters are determined using accepted engineering design practices in conjunction with the teachings of the embodiment of FIG. 3 .
A flow chart showing the method of the present invention is provided by FIG. 5. A near end signal is transmitted, step 510 , and energy in the near end signal goes to a sense winding and to a replica network for generating a replica. Energy from a far end signal is received at the sense winding, step 520 . Both near end energy and far end energy is coupled to the sense winding. The voltage across the sense winding is provided to a receiver, step 530 , or more specifically to the inverting input of a receive amplifier. In addition, a replica of the near end signal is generated, step 540 , and provided to a non-inverting input of the receive amplifier, step 550 . The voltage across the sense winding and replica are combined by the receive amplifier, thereby generating a receive signal containing mostly far end energy, step 560 . According to the preferred method of the present invention, the sense winding has an independently selectable number of turns for optimizing the signal-to-noise ratio of the received far end signal, and is biased at an independently selectable DC voltage so as to allow for compatibility with various types of receiver circuits.
If the amount of near end energy in the receive signal is to be kept small, then the transfer function from the output of the transmit amplifier to the input of the receive amplifier must be matched by that of the replica transfer function generating circuit.
From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the novel concept of the invention. It is to be understood that no limitation with respect to the specific methods and apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims. | A method and apparatus for providing an improved telephone hybrid function is provided. The present invention uses a transformer having an galvanically isolated sense winding to improve hybrid performance. Performance improvements include removing the effects of variations in winding resistance, independently adjusting a pick-off voltage, reducing the effects of transformer leakage inductance, providing DC isolation between circuits and increasing the signal to noise ratio at the receiver. | 7 |
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
This is a division of application Ser. No. 07/498,255, filed Mar. 23, 1990, now U.S. Pat. No. 5,041,522.
BACKGROUND OF THE INVENTION
This invention relates to rod-like heterocyclic aromatic polymers.
Considerable research has been directed toward the synthesis of extended chain or rod-like polymers. The unique ordering properties of these polymers has led to the preparation of extremely high modulus/high strength fibers.
Considerable other research has been devoted to electrically conducting polymers. It has been estimated that replacement of copper wiring in large aircraft with electrically conductive polymer "wires" could result in a weight saving of several hundred pounds. Such a savings in weight would be reflected in a savings in fuel.
A major portion of this research has been directed to polyacetylene. This polymer can be doped by a large variety of substances to room-temperature conductivities of about 10 3 ohm-cm -1 . Aromatic polymers such as polyphenylene, polyphenylenevinylene (PPV), and polyphenylene sulfide (PPS) have also been shown to undergo increases in electrical conductivity when exposed to various electron-donor or -acceptor compounds.
It is an object of the present invention to provide novel rod-like heterocyclic aromatic polymers.
It is another object of the present invention to provide novel rod-like heterocyclic aromatic polymers which are at least semi-conducting.
Other objects, aspects and advantages of the present invention will become apparent to those skilled in the art form a reading of the following detailed description of the invention.
SUMMARY OF THE INVENTION
In accordance with the present invention, there are provided novel rod-like heterocyclic aromatic polymers having repeating groups of the formula: ##STR2## wherein Y is --S--, --O-- or --NR--, wherein R is selected from the group consisting of -H, alkyl having 1 to 4 carbon atoms and aromatic having 1 or 2 aromatic rings. The bullet symbol (•) indicates hydrogen bonding.
DESCRIPTION OF THE INVENTION
Polymers I and II are prepared by reacting an amino monomer of the formula: ##STR3## respectively, wherein Y is as defined above, wherein x is 2 or 4, depending on the number of amino groups in the molecule, with 2,5-dihydroxyterephthalic acid, in polyphosphoric acid (PPA).
The 2,5-dihydroxyterephthalic acid may be prepared from diethyl-1,4-cyclohexanedione-2,5-dicarboxylate according to the following reaction sequence: ##STR4##
In carrying out the polymerization, the amino monomer Ia or IIa is initially dehydrochlorinated. This is accomplished by mixing the monomer Ia or IIa and the 2,5-dihydroxyterephthalic acid with polyphosphoric acid and heating the mixture under an inert gas atmosphere at a temperature ranging from about 60° to 80° C. for a period of about 6 to 24 hours. In general, stoichiometric quantities of the monomers are used, although a slight excess of one of the monomers may be used.
Following dehydrochlorination, the reaction mixture is heated at a temperature in the approximate range of 100° to 200° C. for a period of about 18 to 36 hours. In a preferred procedure, the reaction temperature is increased gradually during the reaction period, e.g., 130° C. for 3 hours, 150° C. for 3 hours, 170° C. for hours, 185° C. for 3 hours, and 195°-200° C. for 16 hours, or 160° C. for 16 hours and 190° C. for 16 hours, or the like. At the end of the reaction period, a small aliquot of the polymer is precipitated from solution into water, washed with water until acid-free and air dried. If the intrinsic viscosity of the polymer in methanesulfonic acid is not within the desired range of about 8 to 31 dl/g, polymerization is continued until an aliquot sample has the desired viscosity.
Intrinsic viscosity is determined by extrapolation of η rel-l/c and ln η rel/c to zero concentration in methanesulfonic acid at 30° C.
At the end of the reaction period, the polymer is precipitated from solution by pouring the reaction mixture into a coagulation bath, such as water or methanol. If a bulk polymer is desired, the reaction mixture is poured directly into the coagulation bath, with or without stirring. The polymer may also be formed into fibers by extruding the polymer/PPA solution through a suitable spinnerette into the coagulation bath. The resulting fiber may be drawn and heat-treated following known procedures.
The following examples illustrate the invention:
EXAMPLE I
Diethyl-1,4-cyclohexanedione-2,5-dicarboxylate is reacted with bromine in cold sulfuric acid (0°-10° C.) to provide the aromatized product, diethyl-2,5-dihydroxyterephthalate. Hydrolysis of the diethyl-2,5-dihydroxyterephthalate by refluxing in aqueous sodium hydroxide followed by acidification with HCl provides 2,5-dihydroxyterephthalic acid. The diacid may be converted to the diacid halide by reaction with thionyl halide in diethyl ether.
EXAMPLE II
Poly[benzo[1,2-d:4,5-d']bisthiazole-2,6-diyl (2,5-dihydroxy-p-phenylene)]
Into the bottom of a resin flask equipped with a high torque mechanical stirrer, nitrogen inlet/outlet, pressure regulator and a side opening for additions, was placed 4.904 g (20 mmol) of 2,5-diamino-1,4-benzenedithiol dihydrochloride, 3.962 g (20 mmol) of 2,5-dihydroxyterephthalic acid and 18.74 g of PPA (77% P 2 O 5 ). The monomers were incorporated into the PPA by stirring. The resulting mixture was then dehydrochlorinated under reduced pressure (176 mm) while slowly heating the mixture to 80° C. The reaction temperature was maintained at 80° C. for 24 hours, then cooled to 60° C. 13.64 g of P 2 O 5 was added to the mixture, thus raising the final polymer concentration to 15%. The mixture was heated under a positive nitrogen flow at 60° C. for 4 hr, 100° C. for 2 hr and 140° C. for 24 hr. As the temperature was increased, opalescence began to appear at about 120° C. The polymer was precipitated into water, collected by suction filtration, washed with ammonium hydroxide, washed with water and dried under reduced pressure (0.02 mm) at 110° C. An intrinsic viscosity of 28 dl/g was obtained in methanesulfonic acid at 30° C.
EXAMPLE III
Poly[benzo[1,2-d:4,5-d']bisoxazole-2,6-diyl (2,5-dihydroxy-p-phenylene)]
Into the bottom of a resin flask equipped with a high torque mechanical stirrer, nitrogen inlet/outlet, pressure regulator and a side opening for additions, was placed 3.873 g (18.2 mmol) of 4,6-diaminoresorcinol dihydrochloride, 4.27 g (18.2 mmol) of 2,5-dihydroxyterephthalyl chloride and 29.3 g of PPA (77% P 2 O 5 ). The monomers were incorporated into the PPA by stirring. The resulting mixture was then dehydrochlorinated under reduced pressure (176 mm) by heating at 60° C. for 24 hr and 80° C. for 5 hr. The reaction mixture was then cooled to 50° C. 13.54 g of P 2 O 5 was added to the mixture, thus raising the final polymer concentration to 14%. The mixture was heated under a positive nitrogen flow at 130° C. for 16 hr, 170° C. for 20 hr and 190° C. for 4 hr. The polymer was precipitated into water, collected by suction filtration, washed with ammonium hydroxide, washed with water and dried under reduced pressure (0.02 mm) at 110° C. An intrinsic viscosity of 21.8 dl/g was obtained in methanesulfonic acid at 30° C.
EXAMPLE IV
Poly[benzo[1,2-d:4,5-d']bisimidazole-2,6 -diyl (2,5-dihydroxy-p-phenylene)]
Into the bottom of a resin flask equipped with a high torque mechanical stirrer, nitrogen inlet/outlet, pressure regulator and a side opening for additions, was placed 5.37 g (18.92 mmol) of 1,2,4,5-tetraaminobenzene tetrahydrochloride, 4.45 g (18.92 mmol) of 2,5-dihydroxyterephthalyl chloride and 30.3 g of PPA (77% P 2 O 5 ). The monomers were incorporated into the PPA by stirring. The resulting mixture was then dehydrochlorinated under reduced pressure (176 mm) by heating at 60° C. for 24 hr and 80° C. for 16 hr. The reaction mixture was then cooled to 50° C. 14.02 g of P 2 O 5 was added to the mixture, thus raising the final polymer concentration to 10%. The mixture was heated under a positive nitrogen flow at 130° C. for 16 hr, 170° C. for 20 hr and 190° C. for 4 hr. The polymer was precipitated into water, collected by suction filtration, washed with ammonium hydroxide, washed with water and dried under reduced pressure (0.05 mm) at 100° C. An intrinsic viscosity of 16.2 dl/g was obtained in methanesulfonic acid at 30° C.
EXAMPLE V
The anisotropic reaction mixture of Example II was spun into monofilament fibers using a dry-jet wet spinning method with a 10 mil. diameter spinnerette and coagulated in distilled water. The air gap where the fiber was stretched was maintained at 8 inches. After neutralization with 3% NH 4 OH and washing with water, the fibers were tension dried at 150° C., then heat treated in a tube oven under an inert nitrogen atmosphere at 435° C. with 30-sec residence time. The resulting fiber had a modulus of 25 Msi, tensile of 304 Ksi and an elongation at break of 1.3%.
Conductivity measurements on the fibers revealed that the as-spun fiber had a conductivity of 10 -7 ohm -1 cm -1 . The heat treated fiber had a conductivity of 10 -8 ohm -1 cm -1 . In contrast, PBT (polybenzothiazole) fibers (without the hydroxy groups on the phenylene moiety) had a conductivity of 10 -12 ohm -1 cm -1 .
The high molecular weight ordered polymers of this invention exhibit excellent strength, modulus and semiconducting properties. The thermal properties of these materials indicate that they will be stable to ion implantation and provide conductivities up to about 10 4 S/cm. These polymers are suitable substitutes for other inorganic or organic products. In particular, the semi-conducting fibers of this invention are suitable for use in reinforcing structures which must bleed off charges of static electricity. The polymers of this invention, with ion implantation, are suitable for replacement of copper wiring.
Various modifications may be made to the invention as described without departing from the spirit of the invention or the scope of the appended claims. | There are provided novel rod-like heterocyclic aromatic polymers having repeating groups of the formula: ##STR1## wherein Y is --S--, --O-- or --NR--, R is -H, an alkyl group having 1 to 4 carbon atoms or an aromatic group having 1 or 2 aromatic rings, and the bullet symbol (•) indicates hydrogen bonding. | 2 |
BACKGROUND
In Quantum invariants of 3-manifolds and quantum computation (“BK”), Bravyi and Kitaev constructed a universal set of gates {g 1 ,g 2 ,g 3 } for the Ising TQFT, the principle component of the Moore Read model for ν=5/2-FQHE, in an abstract context in which there were no restrictions on the global topology of the space-time. Gate g 1 may be referred to as a π/4 phase gate. Gate g 2 may be referred to as a controlled π phase gate. Gate g 3 , which has no real name, may be used for braiding.
For a laboratory device, the relevant space-time should embed in R 2 ×R 1 . It seems almost certain that simply adding this constraint to the Bravyi/Kitaev context prevents the construction of a complete gate set. However, if a certain assumption is added to their model—i.e., that the topological changes 1, σ and ε can be distinguished on a simple (framed) loop γ in space-time—then {g 1 ,g 2 ,g 3 } may be realized in 2+1 dimensions. Projecting to the charge sectors 1, σ and ε extends the discussion of Topologically-Protected Qubits from a Possible Non-Abelian Fractional Quantum Hall State, by Das Sarma, Freedman, and Nayak (“DFN”), in which interferometry was proposed to distinguish the 1 and ε changes. By an extension of DFN, an interferometry measurement should be able to resolve the identity into the sum of three projectors: 1d={circumflex over (1)}⊕{circumflex over (σ)}⊕{circumflex over (ε)}. A further generalization, however, is needed.
SUMMARY
A logical gate for a quantum computer can be achieved by forming a Polyakov loop in the space-time of a fractional quantum Hall effect (FQHE) fluid, and determining a charge on the Polyakov loop. Time-tilted interferometry provides a mechanism by which to measure charge on Polyakov loops, which extend over time and cannot be deformed into a single time slice. Measuring charge on Polyakov loops is equivalent to using exotic topologies as in BK. The jump from the physically-impossible world of BK to the physically possible world is the recognition that measuring the charge on the Polyakov loops is the equivalent of BK's exotic topologies. Thus, a probabilistic realization of BK's gates can be achieved with enough fidelity to be tantamount to a realization of BK's gates.
To break the fluid, a current may be injected at the first antidot at a first time. The voltage may be turned on at a later time to create a gap (thus beginning the formation of a Polyakov loop). The voltage may be removed at a still later time to heal the gap (thus closing the Polyakov loop). The current may then be removed to ground and measured. Measurement of the output current will cause the “particle” to converge to an eigenstate (i.e., |1> or |ε>). If the measured current is relatively high, then the Polyakov loop is in a first state (e.g., |1> or |ε>). If the measured current is relatively low, then the Polyakov loop is in a second state (e.g., |1> or |ε>, respectively).
By adding gammas, one can determine whether a |1> or |ε> particle is in the Polyakov loop. It should be understood that there may never really be an epsilon particle in the Polyakov loop, but it behaves as if there is. Using time-tilted interferometry, one can determine whether the Polyakov loop is in a |1> state or and |ε> state.
There is no tunneling path when the fluid is broken. The fluid may be broken by increasing the voltage on a gate to separate the Hall bar into two smaller bars. It should be understood that an actual break in the fluid is not necessary. Any separation of the anti-dots (e.g., electrically or spatially) so that no tunneling can occur is sufficient.
A particle can start to tunnel before the bar is broken, linger between the antidots while the gap is present, and get across to the other antidot after the gap is repaired. Likewise, a particle can start to tunnel before the bar is broken, and get past the area where the Polyakov loop is formed, but have an amplitude such that it lingers on the other side of the loop until the gap is closed before getting to the second antidot.
It should be understood that there might be a classical electromagnetic contribution that needs to be calibrated out. That is, classical phase shifts must be calibrated away. To calibrate, the bar is not broken (equivalent to having |1> particle, which is no particle at all). The current drawn out to ground can be measured in the absence of a break in the fluid. Then, the fluid can be broken, a determination can be made as to whether anything changed as a result. If nothing changes, then the particle is in a |1> state. If the current changes, then the particle is in an |ε> state. Accordingly, in operation, if the measured current is the same as the calibrated current, then the particle is in a |1> state. Otherwise, the particle is in an |ε> state.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B depict a FQHE fluid on the inside and outside, respectively, of the bounding edge(s).
FIG. 2 depicts contributions from two tunneling paths for σ particles.
FIG. 3 depicts a plane filled with FQHE fluid except for two distorted anti-dots.
FIG. 4 depicts measurement of charge around a time-like hole in a band of material such as an FQHE fluid.
FIG. 5 depicts upper and lower tunneling trajectories.
FIGS. 6A and 6B depict geometry for interferometry around a loop using one fixed anti-dot and one moving anti-dot.
FIG. 7 depicts a twice-punctured disk or “pants.”
FIG. 8 depicts a representation of qubits.
FIG. 9 depicts a compact representation of qubits as for Wilson (Abrikosov) loop segments.
FIG. 10 depicts a representation that follows from the braiding rules of the Ising TQFT.
FIG. 11 depicts the sum of charges on two boundary components.
FIG. 12 depicts an overpass.
FIG. 13 depicts skein relations.
FIGS. 14A and 14B depict a realization of a π/4 phase gate g 2 .
FIG. 15 depicts the gate realization of FIG. 14A reproduced in slices.
FIGS. 16A and 16B depict results when the fluid is rejoined and the σ's fused.
FIG. 17 shows that two simply linked σ trajectories cannot occur in a box of space-time fluid, but can occur if only part of the box is filled with 5/2's fluid.
FIG. 18 depicts a realization of a controlled π phase gate g 1 .
FIG. 19 depicts a +1-Dehn twist.
FIG. 20 depicts an ε-Polyakov loop at level ½.
FIG. 21 depicts a W=P×I∪1-handle.
FIG. 22 depicts the probability for γ to carry charge 1(ε).
FIGS. 23A and 23B depict FIG. 22 in particle flight (Feynmann diagram) notation according to the charge of γ.
FIG. 24 is a block diagram showing an example computing environment in which aspects of the invention may be implemented.
DETAILED DESCRIPTION
To realize gates g 1 and g 2 one must measure interference between paths γ 1 and γ 2 , which cannot simultaneously be projected into any (planar) space-time-slice. The techniques described herein are analogous to a “twinkling” double slit experiment where the two slits rapidly open and close and though never simultaneously open, produce an interference pattern. Such a technique may be referred to as “tilted interferometry” since the loop γ=γ 1 ∪γ 2 −1 may have the property that it cannot be deformed into any single time-slice and so is tilted in space-time. It has been suggested that “tilted interferometry” is analogous to the second, electric Arharonov-Bohm effect, where case A 0 , must vary in time as the particle passes. As described below, the domain of the FQHE fluid will vary in time. It should be understood that interferometry may not be possible along any knotted loop γ, but only fairly simple γs are necessary. To build the gates g 1 and g 2 , the link along which interferometry is done has only one local max (min) per component, i.e., is the “plat of a pure braid.” The third gate, g 3 , is a simple braid generator and requires no discussion here.
For reference:
g 1 = 1 0 0 ⅇ πⅈ / 4 ,
g 2 = 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 - 1 ,
and g 3 1 0 0 i 0 1 i 0 0 i 1 0 i 0 0 1
The Possibilities for Interferometry on the Ising TQFT
In this section, we briefly describe model experiments in the context of ν=5/2 FQHE, some of which will be used to construct g 1 and g 2 as described below. Let us begin without the time tilt. Consider a disk of ν=5/2 FQHE material in which current is injected at A, withdrawn at B and C. Tunneling paths t 1 and t 2 are marked. An unknown topological charge resides on the antidot X.
FIGS. 1A and 1B show two functionally equivalent setups. In FIG. 1A , the FQHE “fluid” is on the “inside” of the bounding edge. In FIG. 1B , the FQHE fluid is on the “outside” of the bounding edges. In space-time “braided tensor category” notation, the two tunneling paths for σ particles contribute as shown in FIG. 2 .
We ignore the U(1)-semion charges and the classical B·A phase to concentrate our attention on the more interesting nonabelian Ising charges:
1= σ=|, and ε=
that is, trivial, spin=½, and spin=1. Using the Kauffman rules:
= A ⊃ ⋐ + A - 1 ⋃ ⋂ , A = ⅇ 3 πⅈ 8
which reproduce the Ising rules up to the Frobeneous-Shor indicator a sign which arises in certain formulae but will not effect our results, and
= -
Note that, using
= - 1 - ( A 2 - A - 2 ) ⋃ ⋂ = - 1 d ⋃ ⋂ , d = 2
the first rule implies the second. We evaluate the interference, FIG. 2 , for x=1, σ, and ε, and t 1 =t 2 .
For x=1:
Tunneling current= t 1 + t 2 =2 t 1
in units charge
(
σ
)
=
e
4
.
For x=σ:
Tunneling current= t 1 + t 2
but it would be a mistake to algebraically combine the two processes since they represent orthogonal kets, which may be checked by pairing with external particles histories and
The results are
=2, =0, =0, and = e −iπ/4 √{square root over (2)},
which may be checked from the Kauffman rules (or the S-matrix—given later). Orthogonality implies the norm of the combined processes is independent of the relative phase. This orthogonality means no change in interference with changing area A. As A can be modulated with a side gate, this property should be experimentally accessible.
For x=ε:
Tunneling
current
=
t
1
(
⊃
|
)
+
t
2
(
)
=
t
1
(
⊃
)
-
t
2
(
)
Formally these three outcomes for x=1, σ, ε are quite distinct. Up to now, we have here only considered the σ—tunneling current. One would also expect a smaller temperature dependent contribution from ε—tunneling which would have to be added to the calculations above. There would be terms:
1. case x=1: t 1 ′ +t 2 ′ 2. case x=σ: t 1 ′ +t 2 ′ and 3. case x=ε: t 1 ′ +t 2 ′ =0
respectively. In any case there is ample independence to expect a relatively simple interferometry measurement around x to project into one of the three sectors 1, σ, or ε.
If a simple loop γ lies in a FQHE liquid at time=t we may project onto particle states 1, σ, or ε along σ by an experiment which is a geometric distortion of, but topologically identical to, FIG. 1B . FIG. 3 depicts a plane filled with FQHE fluid except for two distorted anti-dots D 1 and D 2 . The asterisks represent quasi-particles. If we could measure the tunneling current between them (and vary area A as we do so), we project to a collective charge 1, σ, or ε along γ. The experiment suggested by FIG. 3 is not tilted but describable within a time slice.
Let us now take up tilted interferometry with σ particles. The basic ideas is that we expect technological limitations to confine us to planar puddles of FQHE fluids at any times slice (i.e., no “overpasses”). Just as with MOSFET technology, planarity can be a severe constraint. But suppose a band of material (e.g., FQHE fluid) A is blocking a new band B which we wish to construct, might we break A, allow B to pass, use B for whatever purpose, break B, and then reconstitute A? If we could measure the charge around the resulting time-like hole γ in A (see FIG. 4 ) and if we found charge=1, it would be, as far as SU(2)-Chern-Simons theory were concerned, as if A were never broken.
In this vein, consider the resistance between anti-dots D 1 and D 2 contained in A over a period of time in which A is broken and rejoined. If this time A is broken is comparable to the tunneling time between D 1 and D 2 (and various delays such as tortuous contours of the FQHE fluid might be employed to achieve this) then the resistance should depend on differences between the upper γ 1 and lower γ 2 tunneling trajectories as in FIG. 5 . We suppose, here, that the experimental set-up is such that current is injected into D 1 near t 0 then withdrawn from D 2 near time t 1 .
We turn to the types of measurement needed to yield gates g 1 and g 2 . In designing a gate, γ might become complicated, needing to avoid some regions of space-time and pass through others. In principle γ might be a knotted in (2+1)-space-time. Fortunately, we only will need to measure the topological charge on a loop γ with one max and one min in space-time (or a multi-loop where each component simultaneously shares this property).
For a simple loop on the boundary of (2+1)-space-time the projection into change super selection sectors
1 ^ = ⊗ charges a a ^
is mathematically well defined. On the other hand, if γ lies in the interior a normal framing to γ is required define this define this decomposition (and different frames changes this decomposition by more than phase factors as would be the case for the S-matrix-conjugated decomposition). In the “untilted case,” the time arrow supplies a natural normal frame. In the tilted case, to produce a normal frame, a “base-point” needs to be mathematically specified on the anti-dots. FIGS. 6A and 6B depict geometry for interferometry around a loop γ (with single space-time max and min) using one fixed anti-dot D 1 and one moving anti-dot D 2 .
Let us consider the physical meaning of the framings on the Polyakov loop is and how it might be dictated. First, how do we think of a tunneling particle? As a Brownian path or a smooth arc? In the former case it might be impossible to assign a framing number, but energy considerations and the finite size of quasi-particles suggest that we should think that most of the amplitude across a tunneling junction is concentrated on the isotopy class of the obvious straight (and zero framed) arc across the junction. We assume that the quasi-particles do not carry angular momentum while they tunnel.
A similar issue arises if we transport a quasi-particle on a moving anti-dot. How do we control the rotation of the quasi-particle on the dot? This question is crucial, for without an answer, there is no distinction between doing (titled) interferometry on ζ i with framing=−1(ζ i −1) and interferometry on (ζ i, 0). We will need to control the framing of the space-time arcs along which we transport antidots. A possible answer is to create an asymmetry: e.g., a “tear drop” shaped anti-dot so that it has a natural base point to record rotation. Whether this is another gimmick, such as using an impurity on an edge to serve as a base point, can control framing seems to depend on the detailed local physics and not be accessible from the effective low energy description, so lies outside the scope of this description. However, exercising experimental control of the framing along the legs of the interferometer appears to be an essential requirement.
Interferometry depends on maintaining a superposition among possible tunneling events. It will be challenging to avoid “measurement” as the geometry and/or position of D 2 in the FQHE fluid is changed, but we see no fundamental reason that this should not be possible. It has been suggested that a “bucket brigade” of anti-dots may be easier to implement than electro-statically moving an anti-dot. These approaches should be functionally equivalent.
The qubits to be manipulated are spanned by the two fusion channels in the Ising CFT:
Equivalently, this degree of freedom may be expressed in a single time slice: Consider a twice punctured disk or “pants” P (as part of a larger medium) in which the two internal boundary components carry σ and the outer boundary carries 1 or ε defining the basis of the qubit X 2 (see FIG. 7 ). The qubits can be represented as in FIG. 8 , or more compactly as for Wilson (Abrikosov) loop segments, as shown in FIG. 9 .
The representation depicted in FIG. 10 follows from the braiding rules of the Ising TQFT. This gate requires no interferometry of any kind, it is simply a braid matrix. Unfortunately the braid matrices in the Ising TQFT define discrete subgroups of PSU(N) so we are forced to use interferometry (or forbidden topology) to complete the gate set.
The next gate we consider
g 2 = 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 - 1 .
It is a “controlled phase” gate. Since the F-matrix of the Ising CFT is the Hadamar matrix:
1 2 = 1 1 1 - 1
which conjugates σ x into σ z , producing g 2 is equivalently powerful to producing
“ controlled NOT ” = 1 0 0 0 0 1 0 0 0 0 0 1 0 0 1 0 ,
but we follow BK in producing g 2 .
First we recapitulate in a geometric language the BK description which involves time slices with “overpasses,” i.e., FQHE fluids which cannot lie in the plane. Then we will rearrange the time coordinate and otherwise adjust the protocol so as we use only planar fluids in each time-slice. The price will be the need to use “titled interferometry” to project onto SU(2)-charge sectors along loops γ which are titled in space-time.
The sum of the charges on the two resulting boundary components δ and ψ ( FIG. 11 ) is 1 or ε according to whether the charge along the overpass (dotted loop, α) is 1−ε or σ. This follows from the S-matrices of the theory:
S ij 0 = 1 / 2 2 / 2 1 / 2 2 / 2 1 / 2 - 2 / 2 1 / 2 - 2 / 2 1 / 2
in basis: 1, σ, ε. Furthermore S σ,σ ε =e iπ/4 is the only nonzero entry for a punctured torus with boundary charge=ε.
Ordinary, untilted, interferometry along ψ projects into one of the states 1 or ε. We hope to be in the sector charge (ψ)=1 and the probability of this is 0.5, because 1 and ε have equal quantum dimensions and therefore equal entropy. If we are disappointed, we simply break the overpass and then reconstitute it. Breaking the overpass returns the qubit to its original state. This follows from a general principle, which is described in the Appendix below, that adding quantum media is reversible simply by deleting what was added (whereas deleting quantum media is generally irreversible). Reconstituting the band yields an independent 0.5 chance of getting the desired trivial charge on ψ. We repeat as necessary until charge (ψ)=1 is observed. Now charge (δ) and charge (α) are perfectly correlated; charge (α)=σ charge (δ)=ε and charge (α)=1 or ε charge (δ)=1.
So far we have been manipulating the pants P supporting the control qubit. Now take the “controlled” qubit and pass it, as a body, around α (see FIG. 12 ). The skein relations shown in FIG. 13 tell us that the controlled qubit picks up a phase of −1 if it is in state |ε> and is unchanged if it is in state |1>. Finally, cut the overpass to return the two pants to their original position. The effect is g 2 . FIG. 14 summarizes our reorganization of g 2 . For clarity, FIG. 14 is reproduced (expect for the detour through (ξ 1 )) in the slices in FIG. 15 . To avoid clutter, we omitted an additional boundary component made from the space-time histories of the edges of an anti-dot D that divides into D 3 and D 4 , which moves and later merges back into D as shown in FIG. 14B .
In FIG. 14A , we do ordinary interferometry along the ξ curves and tilted interferometry along γ=D 1 ×time ∪D 2 ×time ∪t 1 ∪t 2 . In other words, we begin forming the “overpass” band B, but now in space-time, and send the controlled qubit, q 2 , down the “band” B as it is found. After a time, the right puncture of the pants supporting the control qubit, q 1 splits and we measure the SU(2)-charge along ξ 1 , hoping to observe 1. This would mean that the channel (diagonal in FIG. 14 ) through which the band B is traveling does not disturb the structure of q 1 .
There are four (equally likely if we neglect energetics associated to electric charge) topological charge splittings
so there is a chance charge (ξ 1 )=1. If charge (ξ 1 )≠1, we fuse back (as shown) and try again until for some i>0, charge (ε 1 )=1 (i=2 in FIG. 14 ). When charge (ξ 1 )=1 we continue the tube across the pants supporting q 1 into the left puncture. Terminate the band B on the left side of the left puncture, allowing q 2 to complete its passage through the time-tilted overpass B.
First, it is clear that the abortive attempts at building the band, ξ i . . . ξ i−1 , to not affect the qubit q 1 (except possibly by an irrelevant overall phase): splitting a into b c and then re-fusing results in the original particle type, is a multiple of the ideality. The “control” qubit q 1 is clearly unaffected since the phase of the operator represent by the insert drawing is independent, by locality, of the state, 1 or ε, of the overall qubit q 1 .
As before, q 1 will control a phase gate
1 0 0 - 1
on q 2 iff (i.e., if and only if) the charge measure along ψ is 1; ψ in FIG. 14 is the difference of the two tunneling paths, t 1 and t 2 between the moving anti-dots D 1 and D 2 . If ε is, instead, measured along ψ, then the gate has inadvertently interchanged the roles of 1 and ε within the controlling qubit q i ; a short calculation shows that
1 0 0 0 0 - 1 0 0 0 0 1 0 0 0 0 1
has instead been affected. This is not too serious since repeated application of the protocol gives a random walk in the group Z 2 ⊕Z 2 generated by
1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 - 1
and
1 0 0 0 0 - 1 0 0 0 0 1 0 0 0 0 1
Our ψ-measurements tell us where we are within Z 2 ⊕Z 2 as we randomly walk, we simply halt upon reaching
1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 - 1 .
The tails on “long walk” decay exponentially so this delay is acceptable.
Perhaps more serious is the fact that the anti-dots D 1 and D 2 must be threaded, along with q 2 , through the band B. D 1 and D 2 should be kept outside tunneling range and the two σ charges inside the pants P 2 carrying q 2 must not be fused. This implies some geometric constraints. Clearly the size of the pants P 1 supporting q 1 must be enlarged, relative to the pants P 2 supporting q 2 before q 1 can be used to control the phase of q 2 . This will be only one of many technological challenges.
With this example of a gate implementation in hand, it makes sense to discuss the general strategy and fundamental principles involved. The general 3-manifold M with boundary does not imbed in R 3 =R 2 ×R but after puncturing M by removing a collection of proper arcs M′=M\arcs will imbed. If the linking circle to a puncturing arc is measured to have charge=1 then the puncture is irrelevant (at least within an SU(2)-Chern-Simons theory). Thus, the strategy is to find some protocol of puncturing and measuring which reduces the topologically intricate gates of BK to a sequence of planar time-slices.
Note that, in calculating the SU(2)-CS partition function Z for the space-time history of a puddle of ν=5/2 FQHE fluid (see BK for algorithms), it is only the intrinsic topology of the resulting 3-manifold which is relevant and not imbedding in R 3 . We give some example to clarify this important point. Our computations intentionally ignore linking not detectable within the space-time.
Suppose a pair of σ's is pulled out of the vacuum and then fused. They will annihilate. If, however, after their births, the fluid is cut to separate them, all correlation is lost. If the fluid is then rejoined and the σ's fused the results will be 1 with probability ½ and ε with probability ½ (see FIG. 16 ). Similarly since the S-matrix entry S σσ 1 =0 two simply linked σ trajectories cannot occur in a box of space-time fluid, but can occur if only part of the box is filled with 5/2's fluid (see FIG. 17 ).
The preceding discussion applies only to the SU(2)-sector of the theory. We have been suppressing the fact that CFT modeling ν=5/2 is a semi direct product of the Ising CFT (a variant of SU(2)-level=2) and a U(1)-semionic theory (U(1)-level=2) in order to concentrate on the more interesting nonabelian charges. Certainly, outside the FQHE space-time there is no sensible SU(2)-connection, which could mediate topological interaction. On the other hand, the U(1) gauge potential is that of ordinary electromagnetism and this pervades all of space-time and it will produce Arharonov-Bohm interactions without regarded to the boundaries of FQHE fluid. However, since the particles in this theory carry electric but not magnetic charges the U(1)-corrections are proportional to flux, A·B (see DFN) and easily made.
We turn now to the final gate
g 1 = 1 0 0 ⅇ π ⅈ / 4 .
The description in BK may be summarized as follows. First, Beginning with a qubit q on a pants P, attach a tube to P to obtain a punctured torus. This is done by first adding a band B and then measuring a charge 1 or ε on the new boundary component. If 1 is measured the tube is regarded as successfully attached; if ε is measured then break the band and try again. Then, let D be Dehn twist in the curve labeled α in FIG. 11 . Act on T by D 2 . Then, cut the band B to change T back into P. Steps 1 , 2 , 3 effect g 1 . The computation follows from knowing the S-matrices and twist parameters θ. If q is in state |1>, the charge along α is 1+ε, θ 1 =1 and θ ε =−1, so under D 2 , (θ 1 ) 2 =(θ ε ) 2 =1 is applied and no phase change occurs. On the other hand, if q is in state |ε>, then the charge along α is σ so D 2 changes phase by (θ σ ) 2 =(e iπ/8 ) 2 =e πi/4 . Note that if D were used instead if D 2 , the result would not operate on the qubit since the charge on the internal punctures would not return to σ after the band B is cut: it would be
1
2
(
1
+
ɛ
)
.
Our proposed implementation of g 1 closely follows this 3-step description. To understand the protocol, refer back to FIG. 14 . Most of the figure depicts activity on P with the second pants P 2 being threaded through a passage roughly from southeast to northwest. Since g 1 is a 1-qubit gate, we dispense entirely with P 2 ; instead we thread two unlinked loops, with framing −1, ζ 1 and ζ 2 through this channel as sketch FIG. 18 (to be “overlain” on FIG. 14 ). We will need to use tilted interferometry to measure ψ, ζ 1 , and ζ 2 . Thus each ζ i , i=1, 2, consists of a moving anti-dot D i carrying a σ-particle accompanied by companion anti-dots D i ′ and D i ″ (moving or in “bucket-brigade”) with a well defined base point determining framing (ζ i −1). The role of D i is to carry a meridional σ-charge while tunneling |t 1 −t 2 | is measured between D i ′ and D i ″ .
We have added a new feature, we have assumed that in preparing the anti-dots D i , that we can pull out of the vacuum and later annihilate at ±pair of σs these have an
electrostatic charge = ( - 1 ) i e 4
so that they, topologically, carry σ. The reason for this constraint is to restrict to two cases 1 or ε, the possible outcomes of each (ζ i ,−1) measurement. Indeed the calculation for the change of basis from the meridial basis (in which s would surely be measured) to the (ζ i ,−1)=L−M (longitude−meridian) is given by S −1 T −1 S |σ> where
S = 1 / 2 2 / 2 1 / 2 2 / 2 0 - 2 / 2 1 / 2 - 2 / 2 1 / 2
and
T = 1 0 0 0 ⅇ ⅈπ / 8 0 0 0 - 1
in the {{1,σ,} basis. We check that S −1 T −1 S |σ>=√{square root over (2)}/2|1>+√{square root over (2)}/2|ε>. This calculation will be justified below.
Ignoring the measurements ξ 1 . . . ξ n which create the |1>-labeled passage between the inner punctures of P as in FIG. 14A , we must execute three titled measurements along ψ, ξ 1 , and ξ 2 . We have just shown that in all cases the outcomes for charge (ξ 1 ) and charge (ξ 1 ) are independent and either 1 or ε. We previously verified charge (ψ)=1 or ε. From this it will follow that the protocol produces
g 1 = 1 0 0 ⅇ ± πⅈ / 4
iff charge
( ψ ) = 1 and ⅇ ± πⅈ / 4 0 0 1
iff charge (ψ)=ε, where + occurs if charge (ζ 1 )·charge (ζ 2 )=1 and −if charge (ζ 1 )·charge (ζ 2 )=ε. The notation used herein is motivated by fusion rules: 1 1=1,1 ε=ε 1=ε, and ε ε=1. In all eight measurement outcomes we have, up to an overall phase, implemented either g 1 or g 1 −1 . Thus our protocol generates a random walk on Z/8Z determined by a fair coin and since we know the measurement outcomes we may iterate the protocol until we arrive at g 1 . Again this is efficient.
It should be understood that, in terms of BK, measuring charge ψ as in FIG. 18 , corresponds to measuring the charge on ψ of FIG. 11 . Measuring the charges on ζ 1 and ζ 2 correspond to the double Dehn twist in a manner which will now be described.
As described above, projection to charge sectors on a loop γ does not become well-defined (or even the eigenspaces themselves) until γ has a normal framing. If the physical Hilbert space V (T) for a torus T is V=span {1,σ,ε} in the longitudinal basis L if we wish to transform to the framing=k basis, L+kM=longitude+k(meridian), we must compute as follows:
the composition given by: S −1 T k S.
The curves ζ 1 and ζ 2 have been described as having framing=−1 this means the tip of the frame vector links −1 with its base as it moves around the loop and that k, above is −1. It is a fundamental identity of the “Kirby calculus” that −1-framed surgery on a simple linking circle imparts a +1-Dehn twist, as depicted in FIG. 19 .
The meaning of “surgery,” as that term is used herein, is that a tubular neighborhood of the loop is deleted and then glued back so that the meridian disk is glued to the circle defined by the tip of the frame vector. Obviously, we can neither twist nor surger Gallium Arsenide, but if we measure the particle content of a (framed) loop γ in the interior of a 2+1-dimensional space-time, and the result is 1, we have (up to an overall normalization factor, corresponding to capping a 2-sphere) accomplished surgery on γ as far as Chern-Simons theory is concerned. Similarly, if we measure a nontrivial particle σ or ε we have still done a kind of surgery but now the reglued solid torus has a particle “Polyakov loop” (σ or ε resp.) running along its core. This is σ(ε)=Z (solid torus, Polyakov loop) ∈V (T 2 ) expressed in meridional basis.
From the S-matrices, we know that (w.r.t., the labeling in FIG. 11 ) charge (α)=1−ε iff charge (ψ)·charge (δ)=1 and charge (α)=σ iff charge (ψ)·charge (δ)=ε. Thus the nontrivial phase arises in the upper left or lower right entry of our gate-matrix according to whether charge (ψ)=1 or ε.
In translating between FIGS. 11 and 18 , α corresponds to untwisted copies of the ζ's, (ζ 1 ,0) and (ζ 2 ,0). Measuring (ζ 1 ,−1) and (ζ 2 ,−1) results in a squared Dehn twist around a with two Polyakov loops appearing, labeled by some particle type 1 or ε, (but not σ!) parallel to α, say at α×⅓ and α×⅔ in a product structure.
The Polyakov loops cannot carry σ since S −1 T −1 S |σ>=√{square root over (2)}/2|1>+√{square root over (2)}/2|ε>. Because two ε's must fuse to 1, only the total charge, charge (ζ 1 ,−1)·charge (ζ 2 ,−1)=1 or ε is relevant to the action of the gate. There are two cases: when charge (δ)·charge (ε)=1, then charge (α)=1−ε, and the effect of an ε-Polyakov loop can be localized as that of a ε-core circle×½ in annulus×[0, 1], where the boundaries of the annulus are labeled by |1> (or |ε>). With either labeling, the ε-Polyakov loop contributes no additional phase. In contrast, in the second case when charge (δ)·charge (ψ)= 8 and charge (α)=σ, the localized model is an ε-Polyakov loop at level ½ in annulus×[0, 1] with boundaries labeled by σ (see FIG. 20 ). In this case the Polyakov loop contributes a phase-1. The phase which the ε-Polyakov loop adds to the identity (product) morphism is:
=1, a= 1; =−1 ,a =σ; and =1 ,a=ε.
Thus it has been shown that our protocol implements g 1 or g 1 −1 according to whether charge (ψ)·charge (ζ 1 ,−1)·charge (ζ 2 ,−1)=1 or ε.
The Effect of Adding or Deleting 1-handles to Pants ×I.
The time history of adding and then breaking a band between the inner boundary components β,ω or a twice punctured disk P is topologically the addition of a 1-handle (D 1 ×D 2 ,∂D 1 ×D 2 )to P×I; call the result W=P×I∪1-handle (see FIG. 21 ). As shown in FIG. 21 , W is drawn with time ≠Z-coordinate since the add/break procedure for the band B does not imbed in (2+1)-dimensions.
While it is axiomatic that products correspond in a TQFT to identity morphisms, it is a small calculation that W induces the identity (rather than say a phase gate) on the qubit supported on P. The general principle is that if a surface which bounds a 3-manifold is broken up into sub-surfaces by (particle) labeled loops, then the 3-manifold canonically specifies a vector in the tensor product of the (relative) physical Hilbert spaces.
Letting x=1 or ε for the outer label, W specifies a vector ψ in: V 0,0 V 0,σ,σ V 0,σ,σ V σ,σ,x V* σ,σ,x V x,x , where the factors come from subsurfaces 1, . . . , 6 in FIG. 21 . The zero label in the first three factors is dictated by the presence of the disks in W capping the boundary of the first component (a cylinder). The gluing axion [W] or [T] tells us that removing the 1-handle determines a canonical isomorphism to Z(P×I) carrying ψ 1 to ψ 0 in V 0 * V 0 V 0,σ,σ V 0,σ,σ V σ,σ,x V* σ,σ,x V x,x . After supplying the canonical base vectors β 0 ∈V 0 ,β 0,σ,σ ∈V 0,σ,σ and β x,x ∈V x,x ,ψ 1 is canonically identified with id ∈. Hom (V σ,σ,x )≈V* σ,σx V σ,σ,x . Note that no x-dependent phase has entered the calculation. Thus we have proved, in the abstract language of TQFTs, that adding and then breaking a band induces the identity operator on the qubit supported in P.
The situation is rather different if, instead we cut out a band to join the internal punctures and then restore it. In other words, fuse the internal punctures and then separate them. We will even assume that we can use the electric charge of the σ, which we take to be
+ ⅇ 4
on both punctures to ensure that is energetically favorable (and hence necessary) that when we split the previously fused puncture back in two, each resulting puncture again carries a
+ ⅇ 4
charged σ. Our calculation will show that even in this situation we have not acted on the P-qubit via the identity by rather a POVM
α ≅ 1 0 0 1 + β ≅ 1 0 0 - 1
where α(β) is the probability for γ in FIG. 22 to carry charge 1(ε). Thus, in general, operations that add quantum media (in this case 5/2-FQHE fluid) are reversible—simply delete what was previously added, whereas operations which delete are often irreversible.
In particle flight (Feynmann diagram) notation FIG. 22 is either FIG. 23A or FIG. 23B , according to the charge of γ. FIG. 23A certainly represents the identity acting on the P-qubit. The operator given by FIG. 23B is clearly diagonal in the (1,ε)basis. To compute the phases of the diagonal entries we pair with the orthonormal exterior basis, √{square root over (2)} and use the Kauffman relations to extract expectation values. In case a we get:
= 2 , and 2 = 2 - 2 ( 1 2 ) = 2 2 - 2 = 2 . =
In this case b we get:
2 = = 2 - 2 ( 1 2 ) = 2 2 -- 2 = 2 , and 2 = 2 ( - 1 2 - 1 2 + 1 2 ) = 2 ( - 2 2 ) = - 2 .
The strange √{square root over (2)} factor is actually S 00 =S εε which has entered because we have not rescaled the dual physical Hilbert space by 1/S xx prior to gluing. Taking this axiomatic factor into account (see BK, for example, or Walker, On Witten's 3-manifold invariants), we obtain the claimed formula.
Example Computing Environment
FIG. 24 and the following discussion are intended to provide a brief general description of a suitable computing environment in which an example embodiment of the invention may be implemented. It should be understood, however, that handheld, portable, and other computing devices of all kinds are contemplated for use in connection with the present invention. While a general purpose computer is described below, this is but one example. The present invention also may be operable on a thin client having network server interoperability and interaction. Thus, an example embodiment of the invention may be implemented in an environment of networked hosted services in which very little or minimal client resources are implicated, e.g., a networked environment in which the client device serves merely as a browser or interface to the World Wide Web.
Although not required, the invention can be implemented via an application programming interface (API), for use by a developer or tester, and/or included within the network browsing software which will be described in the general context of computer-executable instructions, such as program modules, being executed by one or more computers (e.g., client workstations, servers, or other devices). Generally, program modules include routines, programs, objects, components, data structures and the like that perform particular tasks or implement particular abstract data types. Typically, the functionality of the program modules may be combined or distributed as desired in various embodiments. Moreover, those skilled in the art will appreciate that the invention may be practiced with other computer system configurations. Other well known computing systems, environments, and/or configurations that may be suitable for use with the invention include, but are not limited to, personal computers (PCs), automated teller machines, server computers, hand-held or laptop devices, multi-processor systems, microprocessor-based systems, programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. An embodiment of the invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network or other data transmission medium. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.
FIG. 24 thus illustrates an example of a suitable computing system environment 100 in which the invention may be implemented, although as made clear above, the computing system environment 100 is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality of the invention. Neither should the computing environment 100 be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary operating environment 100 .
With reference to FIG. 24 , an example system for implementing the invention includes a general purpose computing device in the form of a computer 110 . Components of computer 110 may include, but are not limited to, a processing unit 120 , a system memory 130 , and a system bus 121 that couples various system components including the system memory to the processing unit 120 . The system bus 121 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus (also known as Mezzanine bus).
Computer 110 typically includes a variety of computer readable media. Computer readable media can be any available media that can be accessed by computer 110 and includes both volatile and nonvolatile, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), Electrically-Erasable Programmable Read-Only Memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CDROM), digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by computer 110 . Communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency (RF), infrared, and other wireless media. Combinations of any of the above should also be included within the scope of computer readable media.
The system memory 130 includes computer storage media in the form of volatile and/or nonvolatile memory such as ROM 131 and RAM 132 . A basic input/output system 133 (BIOS), containing the basic routines that help to transfer information between elements within computer 110 , such as during start-up, is typically stored in ROM 131 . RAM 132 typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit 120 . By way of example, and not limitation, FIG. 24 illustrates operating system 134 , application programs 135 , other program modules 136 , and program data 137 . RAM 132 may contain other data and/or program modules.
The computer 110 may also include other removable/non-removable, volatile/nonvolatile computer storage media. By way of example only, FIG. 24 illustrates a hard disk drive 141 that reads from or writes to non-removable, nonvolatile magnetic media, a magnetic disk drive 151 that reads from or writes to a removable, nonvolatile magnetic disk 152 , and an optical disk drive 155 that reads from or writes to a removable, nonvolatile optical disk 156 , such as a CD ROM or other optical media. Other removable/non-removable, volatile/nonvolatile computer storage media that can be used in the example operating environment include, but are not limited to, magnetic tape cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM, solid state ROM, and the like. The hard disk drive 141 is typically connected to the system bus 121 through a non-removable memory interface such as interface 140 , and magnetic disk drive 151 and optical disk drive 155 are typically connected to the system bus 121 by a removable memory interface, such as interface 150 .
The drives and their associated computer storage media discussed above and illustrated in FIG. 24 provide storage of computer readable instructions, data structures, program modules and other data for the computer 110 . In FIG. 24 , for example, hard disk drive 141 is illustrated as storing operating system 144 , application programs 145 , other program modules 146 , and program data 147 . Note that these components can either be the same as or different from operating system 134 , application programs 135 , other program modules 136 , and program data 137 . Operating system 144 , application programs 145 , other program modules 146 , and program data 147 are given different numbers here to illustrate that, at a minimum, they are different copies. A user may enter commands and information into the computer 110 through input devices such as a keyboard 162 and pointing device 161 , commonly referred to as a mouse, trackball or touch pad. Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 120 a - f through a user input interface 160 that is coupled to the system bus 121 , but may be connected by other interface and bus structures, such as a parallel port, game port or a universal serial bus (USB).
A monitor 191 or other type of display device is also connected to the system bus 121 via an interface, such as a video interface 190 . In addition to monitor 191 , computers may also include other peripheral output devices such as speakers 197 and printer 196 , which may be connected through an output peripheral interface 195 .
The computer 110 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 180 . The remote computer 180 may be a personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computer 110 , although only a memory storage device 181 has been illustrated in FIG. 24 . The logical connections depicted in FIG. 24 include a local area network (PLAN) 171 and a wide area network (WAN) 173 , but may also include other networks. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet.
When used in a PLAN networking environment, the computer 110 is connected to the PLAN 171 through a network interface or adapter 170 . When used in a WAN networking environment, the computer 110 typically includes a modem 172 or other means for establishing communications over the WAN 173 , such as the Internet. The modem 172 , which may be internal or external, may be connected to the system bus 121 via the user input interface 160 , or other appropriate mechanism. In a networked environment, program modules depicted relative to the computer 110 , or portions thereof, may be stored in the remote memory storage device. By way of example, and not limitation, FIG. 24 illustrates remote application programs 185 as residing on memory device 181 . It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used.
One of ordinary skill in the art can appreciate that a computer 110 or other client devices can be deployed as part of a computer network. In this regard, the present invention pertains to any computer system having any number of memory or storage units, and any number of applications and processes occurring across any number of storage units or volumes. An embodiment of the present invention may apply to an environment with server computers and client computers deployed in a network environment, having remote or local storage. The present invention may also apply to a standalone computing device, having programming language functionality, interpretation and execution capabilities.
Though the invention has been described in connection with certain preferred embodiments depicted in the various figures, it should be understood that other similar embodiments may be used, and that modifications or additions may be made to the described embodiments for practicing the invention without deviating therefrom. The invention, therefore, should not be limited to any single embodiment, but rather should be construed in breadth and scope in accordance with the following claims. | Experiments suggest that the mathematically weakest non-abelian TQFT may be physically the most robust. Such TQFT's—the ν=5/2 FQHE state in particular—have discrete braid group representations, so one cannot build a universal quantum computer from these alone. Time tilted interferometry provides an extension of the computational power (to universal) within the context of topological protection. A known set of universal gates has been realized by topologically protected methods using “time-tilted interferometry” as an adjunct to the more familiar method of braiding quasi-particles. The method is “time-tilted interferometry by quasi-particles.” The system is its use to construct the gates {g1, g2, g3}. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to hoists but more particularly relates to mobile hoists for lifting wall and/or ceiling panels used in building construction.
Most buildings are constructed utilizing available forms of cladding for internal walls, which cladding generally comprises flat sheets or panels of various dimensional sizes and weights. Ceilings and internal walls are generally lined with these panels. Where large panels are used, the weight of those sheets makes fixation thereof at least a two and preferably a three man job. The panels are heavy, cumbersome and hard to handle especially where panels are to be placed on the ceiling.
Wallboard panels made from plaster and cardboard are not stiff enough to resist bending and must be carefully handled so that they are kept substantially flat during installation to prevent snapping. For long panels this necessitates adequate support of the panels until they are fixed in position.
In recognition of this problem, special hoists have been constructed for handling panels such as wallboards. One such hoist is the subject of U.S. Pat. No. 3,828,942.
That invention comprises a lifting device for lifting ceiling panels into place flush against the ceiling beams for installation. The device has a supporting structure for supporting the panel and telescopic sleeves for raising and lowering the panels. The device also has a cable and pulley connecting structure for telescoping the sleeves with a drum or spool for winding the cable and a brake mechanism for the drum. The supporting structure may also be pivoted at an angle and carry thereon panels for installation against the upright wall framework.
More particularly, that invention comprises a lifting device for lifting and aligning wallboard panels to and with the ceiling and vertical walls for installation of the panels to the interior frame of a building. The device comprises a telescopic shaft or sleeve structure, an upright frame, a drum mounted to the upright frame having a wheel for rotating the drum, a plurality of pulleys mounted to the telescopic structure and frame, a cable extending from the drum and about the pulleys and interconnecting the telescoping shaft structure whereby rotation of the drum in one direction by turning the wheel will telescope the telescopic shaft structure. Spaced apart support beams are mounted to the upper end of the telescopic shaft structure each of which have hooks at one end whereby a panel may be placed upon the support beams retained by the hooks and raised vertically to the ceiling by the telescopic structure. The support structure may be pivoted to a selected angle whereby the panel rests in the hooks. The device can then be moved toward a vertical wall framework to facilitate placement of the panel in position against the vertical wall for installation of the panel.
One disadvantage of this device is that the user is still required to lift the wall and ceiling panels onto the device itself. Once the panel is lifted by hand onto the device, the device is operated in the usual way by hoisting the ceiling or wall panel into position. It is quite difficult for one individual to lift heavy panels onto the hoist. Using the existing hoist it is still generally a two man job.
SUMMARY OF THE INVENTION
The present invention seeks to overcome this problem by providing a panel lifting and transporting assembly which enables a panel to be lifted from a position off the assembly to a support structure on the assembly.
More particularly the present invention provides an assembly including a panel lifting apparatus for attachment to a panel hoist or panel support trolley thereby providing means to enable lifting of a panel to be fixed to the surface of a building onto the hoist.
The attachment comprises:
means for enabling attachment of the apparatus to a supporting hoist or trolley, clamping means for gripping a panel to be lifted;
control means directly or indirectly linked to the clamp to enable movement/lifting of the panel onto the hoist. Preferably, the attachment is detachable from the hoist and also foldable.
In one broad form the present invention comprises;
a panel lifting assembly including an apparatus for use with a panel lifting hoist or trolley for transferring a panel from an off the hoist or trolley location onto the hoist or trolley in preparation for lifting of said panel to the point of fixation;
the apparatus comprising;
means to enable releasable attachment of the apparatus from the hoist or trolley,
clamp means for grippingly engaging a panel to be lifted;
control means for moving the panel to be lifted from an off assembly location to an on assembly location.
Preferably the attachment apparatus is foldable and is used with an adapter with a connecting saddle which receives a wedge plate on the apparatus.
In another form of the invention, the attachment previously described is mounted on its own supporting trolley enabling carriage and transport of panels.
In its broadest form, the present invention comprises:
a panel lifting assembly comprising;
a panel support hoist or trolley having at least a ground engaging carriage and a support structure, a panel lifting apparatus having means to enable detachable attachment of the apparatus to and from the hoist or trolley;
characterized in that the panel lifting apparatus comprises;
a primary support member,
a clamp for gripping engagement with a panel to be lifted,
control means for actuating the clamp via a cable which links the clamp and the control means;
wherein when a panel is to be lifted from a position off the assembly and onto the assembly, the clamp is brought into engagement with the panel and the control means actuated to draw the panel onto the assembly enabling support and carriage thereof.
In another form the present invention comprises;
a panel lifting apparatus for detachable attachment to a panel lifting hoist or trolley the apparatus comprising;
a primary support member,
a clamp for gripping engagement with a panel to be lifted,
control means for actuating the clamp via a cable linking the clamp and the control means;
wherein when a panel is to be lifted from a position off the assembly and onto the hoist or trolley, the clamp is brought into engagement with the panel and the control means actuated to draw the panel onto the hoist or trolley enabling support and carriage thereof.
In another form the present invention comprises:
a panel lifting trolley of the type comprising a ground engaging carriage, a substantially upright mainframe, a panel support platform connected to the mainframe and capable of being tilted characterised in that the panel support platform has thereon a saddle which detachably receives a wedge plate on a panel lifting apparatus which locates on the support platform; further characterised in that the panel lifting apparatus comprises;
a primary support member,
a clamp for gripping engagement with a panel to be lifted,
control means for actuating the clamp via a cable linking the clamp and the control means;
wherein when a panel is to be lifted from a position off the trolley and onto the trolley, the clamp is brought into engagement with the panel and the control means actuated to draw the panel onto the trolley enabling support and carriage thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail and in each of its forms according to preferred but non limiting embodiments and with reference to the accompanying illustrations wherein;
FIG. 1 shows a prior art hoist;
FIG. 2 shows an isometric view of the panel lifting apparatus according to one form of the present invention;
FIG. 3 shows a cross sectional elevational view of the upper part of the apparatus of FIG. 1.
FIG. 4 shows a carriage trolley adapted to receive the apparatus of FIG. 2.
FIG. 5 shows an alternative carriage to that shown in FIG. 4; and
FIG. 6 shows an isometric view of a trolley adapted to receive the apparatus of FIG. 2.
FIG. 7 shows the trolley of FIG. 6 with the panel support platform rotated; and
FIG. 8 shows a front elevational view of the trolley of FIG. 6 with the apparatus of FIG. 2 fitted.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 there is shown a known prior art panel lifting hoist 1. The hoist 1 comprises an upright mainframe 2 which comprises a telescopic sleeve structure 3 and splayed legs 4. The upright mainframe supports generally H-shaped platform 6 which is used for supporting a panel (usually a wall or ceiling panel) and placing that panel at the location at which it is to be affixed. The H-shaped panel support platform 6 may be elevated by means of telescopic members 7 and 8. Connecting the upright main frame to the H-shaped platform 6 is pivot 9 which allows the platform 6 to be rotated so that the panel carried by the platform can be presented at the correct attitude for fixing. Thus, the platform 6 can be disposed so that panels for fixing to walls can be presented directly to the wall or alternatively platform 6 can be rotated to a substantially horizontal attitude so that it presents a panel facing a ceiling. Platform 6 generally comprises a longitudinal beam 10 and transverse arms 11 and 12. The transverse arms 11 and 12 have at one end of each arm saddles 13 and 14. The H-shaped member also has extension arms 15 and 16 to enable an increase in the length of the support platform for larger panels. With this platform configuration panels of most, if not all, sizes can be supported on the platform.
Upright main frame 2 is also adapted with support frame 2a which supports cable drum 17 and drive wheel 18. When the panel support platform 6 is to be elevated the drive wheel 18 is rotated causing cable 19 to elevate H-shaped panel support platform 6 via telescopic members 7 and 8.
The main disadvantage of the above described prior art panel lifting hoist is that it is necessary for a user to lift a panel from the floor and onto the platform. Wall and ceiling panels are often large and difficult for an individual to manage thus making it inconvenient for one person to constantly be lifting heavy panels onto the hoist.
Referring to FIG. 2 there is shown a panel lifting apparatus 20 which is an improvement on the prior art hoist and may be used on its own or in conjunction with other means of support such as a trolley (see FIGS. 4 and 5) or, alternatively, may be used as an attachment to a modified trolley (See FIG. 6) or to an existing hoist an embodiment of which has been previously described with reference to FIG. 1.
Panel lifting apparatus 20 comprises a support column 21 of indefinite length. This column may be varied in height/length according to particular requirements. Column 21 is adapted with a wedge plate 22 which engages with tapered saddle 24 on adaptor 23. The adaptor 23 is equipped to enable attachment to the typical prior art hoist as shown in FIG. 1 or to the trolley shown in FIG. 6. The attachment typically takes place by affixing the adapter 23 to longitudinal arm 10 of the prior art hoist by means of hinged posts 25 and 26. Adapter 23 is placed over the longitudinal arm 10 on release of the hinged post 25 and 26 and these are then secured by means of bolts and wing nuts 28 and 29 respectively.
In use, the hoist assembly 20 is connected to saddle 24 via wedge plate 22 as shown by the arrows 30. In use, a panel 31 is gripped in recess 32 by jaws 33 and 34 of clamping assembly 35. The clamping assembly 35 is also equipped with a pantograph 36 which operates the jaws under the assistance of spring bias 37.
When a panel is to be lifted by the jaws, the clamping assembly can be brought down to engage with a panel for instance, lying on the floor and it can be connected with very little effort by the operator. Once the jaws are clamped to the panel by exerting tension on cable 41 on turning of wheel 38 the operator can then start to draw the panel up the column 21 by further operating drive wheel 38 via handle 39. The drive wheel 38 is associated with cable drum 40 around which travels cable 41. The cable travels via pulley 42 and pulley 43 and finally terminates at cable anchorage 44. With this arrangement a simple turning of the drive wheel urges clamping assembly 35 up the support column 21 thereby drawing the panel up and along the column 21. When the hoist assembly 20 is attached to the prior art panel lifting hoist 1 the H-shaped frame can be rotated in the usual manner to orient the sheet in the correct attitude for presentation to the surface to which the panel is to be fixed.
Referring to FIG. 3 there is shown a side elevational cross sectional view of a portion of the panel lifting apparatus of FIG. 2. From this view it can be seen that the column has disposed therein a stop 45 which engages with an arresting arm 46 which is in turn attached to jaw 34. The stop has the effect of arresting the movement of the clamping assembly 35 when it has reached its maximum allowable travel.
Referring to FIG. 4 there is shown a trolley 47 having a ground engaging main frame 48 and support column 49. The main frame 48 is supported on castors 50. Support column 49 has a tapered saddle configured similar to the adaptor 23 shown in FIG. 2. The panel lifting apparatus 20 as shown in FIG. 2 can be inserted into the tapered saddle 51. Thus, wedge plate 22 may be inserted into saddle 51 shown in FIG. 4. In this way a panel may be lifted from a floor surface or from an attitude leaning against the wall and may be transported around the room to a different location without an operator having to lift the panel.
FIG. 5 shows an alternative carriage 52 comprising a single support column 53 and castor wheel 54. The support column is adapted with tapered saddle 55 which receives wedge plate 22 of the panel lifting apparatus 20. The assemblies of FIGS. 4 and 5 may be used for transportation of a panel. The weight of the panel when in the clamping assembly 35 as shown in FIG. 2 increases the gripping force against the panel thereby ensuring safety during lifting.
Referring to FIG. 6 there is shown an isometric view of a trolley 60 for use with the panel lifting apparatus 20 shown in FIG. 2.
The trolley comprises a panel support platform 61 which comprises a longitudinal beam 62 and transverse arms 63 and 64. Both the beam 62 has telescopic extension arms 65, 66.
Transverse arms 63 and 64 have knobs 67, 68 which can be turned to allow saddle arms 69 and 70 to also turn to allow a panel of wallboard to be lowered by depressing spring clip 71.
The panel lifting apparatus of FIG. 2 may be connected to the trolley via saddle 72.
The transverse arms 63 and 64 are connected to longitudinal beam 62 via additional saddles 73 and 74.
Likewise the longitudinal beam 62 is connected to supporting legs 75 and 76 via saddles 77 and 78. The saddles 77 and 78 wedge onto hinges 79 and 80.
The hinges enable rotation of the platform 61 in the direction of arrow 81.
FIG. 7 shows the trolley of FIG. 6 rotated in the direction of arrow 81.
FIG. 8 shows a front elevational view of the trolley shown in FIG. 6 this time with the panel lifting apparatus shown in FIG. 2 fitted thereto.
The panel lifting apparatus according to one aspect of the present invention may in addition to its use as an attachment to a prior art hoist assembly be used for lifting sheets over considerable heights for instance from lower floors to upper floors in buildings along outside walls. Alternatively, the jaws may be used with a short piece of cable as a convenient hand tool for carrying panels.
It will be recognized by persons skilled in the art that numerous variations and modifications may be made to the present invention without departing from the overall spirit and scope of the invention as broadly described herein. | There is provided a panel lifting apparatus for detachable attachment to a panel lifting hoist or trolley. The apparatus comprises a primary support member, a clamp for gripping engagement with a panel to be lifted, a control device for actuating the clamp via a cable linking the clamp and the control device. When a panel is to be lifted from a position off the apparatus and onto the hoist or trolley, the clamp is brought into engagement with the panel and the control device is actuated to draw the panel onto the hoist or trolley enabling the support and carriage of same. | 4 |
BACKGROUND
[0001] Fish hold many aspects of the immune system similar to those of higher vertebrates. Until now, a number of cytokines have been identified in biological assays on the basis of their functional similarity to mammalian cytokine activities or detected through their biological and/or antigenic cross-reactivity with mammalian cytokines (1). Recently, using computer-based tools, an IL-10 homologue was characterized in the puffer fish, ( fugu rubripes ) and predicted to have 183 amino acids (2). We recently characterized the IL-10 cytokine homologue in tilapia and carp using anti human mAb. SDS-PAGE results showed that IL-10L MW in both tilapia and carp is about 15 kDa. Such homology indicates that perhaps it also plays a major role in the fish immune system. AS101 (ammonium trichloro [dioxyethylene-O, O′] telurate) is a low molecular weight, non toxic compound that has been shown to have immune regulatory properties (3). Most of its activities have been primarily attributed to the direct inhibition of the anti-inflammatory cytokine IL-10, followed by the simultaneous increase of other cytokines, such as IL-1α, TNFα, IFNγ, IL-2, IL-12, and GM-CSF (3-6). We examined the effect of AS101 on intracellular levels of tilapia IL-10L in vitro and showed its ability to decrease intracellular IL-10L synthesis in a dose dependent manner. Stress response facilitates IL-10 production and secretion (7), which can cause immune suppression (8). In this study we showed that IL-10L secretion in vivo is up-regulated during stress reaction in fish, and that AS101 is able to decrease that secretion, without affecting the normal stress reaction as indicated by elevated serum glucose levels. Moreover, a protective effect of AS101 on stressed goldfish ( Carassius auratus ) infected with the opportunistic pathogen Aeromonas salmonicida was found. Interleukin-10 (IL-10) is known in mammalians to down-regulate the cellular immunity, resulting in increased susceptibility to opportunistic disease. The ability of the immunomodulator AS101 to down-regulate IL-10 levels has been shown in murines and humans. We have discovered an IL-10-like (IL-10L) cytokine in Tilapia and Carp fish using Western-Blot analysis with human IL-10 mAb and ELISA, and showed IL-10L kinetic expression of LPS stimulated cultures. We have also discovered that air-exposure stress resulted in the in vivo increase of serum IL-10L levels with the increase of blood glucose.
SUMMARY OF THE INVENTION
[0002] Treatment of fish and crustaceans and in particular stressed fish by exposure to organic based tellurium compounds such as AS101 causes significant inhibition of IL-10L secretion to the serum, without affecting the normal stress reaction of the fish as expressed in increased glucose levels. Moreover stress induced Goldfish that were infected with Aeromonas salmonicida bacteria and treated with AS101 had significantly less wounds and mortality than control fish. Accordingly, the invention is directed to the direct or adjunct treatment of bacterial or fungal infections in fish and crustaceans including shell fish. The terms fish and crustaceans are used to include all species of fresh water and salt water fish including fish that are raised in fish farm environments or tropical pet fish as well as lobsters, crayfish, clams, oysters, shrimp, muscles and the like. The invention contemplates providing in the aqueous environment of the fish or crustaceans an amount of an organic tellurium compound that inhibits or treats an infection in fish or crustaceans. These amounts may vary but generally from 0.01 to 10 micrograms of the tellurium compound per ml of water may be employed. The invention also contemplates the concomitant administration of antibiotics, antifungal drugs in conventional doses along with an organic tellurium compound.
BRIEF DESCRIPTION OF THE DRAWING
[0003] FIG. 1 discloses a dose-dependent inhibition of IL-10L by the immunomodulator AS101.
[0004] FIG. 2 discloses Serum IL-10L levels as measured prior to stress induction and at different intervals of time following stress induction
[0005] FIG. 3 discloses stress induction up-regulates IL-10L and glucose secretion, however, + only IL-10L is inhibited when stressed fish are treated with AS101.
[0006] FIG. 4 discloses AS101 treated fish infected with Aeromonas salmonicida show significantly less wounds (p=0.073) than untreated infected fish.
[0007] FIG. 5 discloses AS101 treated stressed fish infected with Aeromonas salmonicida show higher survival rates than control fish.
DETAILED DESCRIPTION OF THE INVENTION
[0008] The organic tellurium compounds for use in the invention include those of the formula:
[0000]
[0000] or
[0000] TeO 2 or complexes of TeO 2 (C)
[0000] or
[0000] PhTeCl 3 (D)
[0000] or
[0000] TeX 4 , when X is Cl, Br or F
[0000] or
[0000] (C 6 H 5 ) 4 P+(TeCl 3 (O 2 C 2 H 4 ))— (E)
[0000] wherein t is 1 or 0; u is 1 or 0; v is 1 or 0; R, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , and R 9 are the same or different and are independently selected from the group consisting of hydrogen, hydroxyalkyl of 1 to 5 carbons, hydroxy, alkyl or from 1 to 5 carbon atoms, halogen, haloalkyl of 1 to 5 carbon atoms, carboxy, alkylcarbonylalkyl of 2 to 10 carbons, alkanoyloxy of 1 to 5 carbon atoms, carboxyalkyl of 1 to 5 carbons atoms, acyl, amido, cyano, amidoalkyl of 1 to 5 carbons, N-monoalkylamidoalkyl of 2 to 10 carbons, N,N-dialkylaminoalkyl of 4 to 10 carbons, cyanoalkyl of 1 to 5 carbons alkoxy of 1 to 5 carbon atoms, alkoxyalkyl of 2 to 10 carbon atoms and —COR 10 wherein R 10 is alkyl of 1 to 5 carbons; and X is halogen; while the ammonium salt is illustrated, it is understood that other pharmaceutically acceptable salts such as K+ are within the scope of the invention. The compounds with the five membered rings are preferred.
[0009] As used herein and in the appended claims, the term alkyl of 1 to 5 carbon atoms includes straight and branched chain alkyl groups such as methyl; ethyl; n-propyl; n-butyl, and the like; the term hydroxyalkyl of 1 to 5 carbon atoms includes hydroxymethyl; hydroxyethyl; hydroxy-n-butyl; the term halkoalkyl of 1 to 5 carbon atoms includes chloromethyl; 2-iodoethyl; 4-bromo-n-butyl; iodoethyl; 4-bromo-n-pentyl and the like; the term alkanoyloxy of 1 to 5 carbon atoms includes acetyl, propionyl, butanoyl and the like; the term carboxyalkyl includes carboxymethyl, carboxyethyl, ethylenecarboxy and the like; the term alkylcarbonylalkyl includes methanoylmethyl, ethanoylethyl and the like; the term amidoalkyl includes —CH 2 CONH 2 ; —CH 2 CH 2 CONH 2 ; —CH 2 CH 2 CH 2 CONH 2 and the like; the term cyanoalkyl includes
[0000] —CH 2 CN; —CH 2 CH 2 CN; —CH 2 CH 2 CH 2 CN and the like; the alkoxy, of 1 to 5 carbon atoms includes methoxy, ethoxy, n-propoxy, n-pentoxy and the like; the terms halo and halogen are used to signify chloro, bromo, iodo and fluoro; the term acyl includes R 16 CO wherein R 16 is H or alkyl of 1 to 5 carbons such as methanoyl, ethanoyl and the like; the term aryl includes phenyl, alkylphenyl and naphthyl; the term N-monoalkylamidoalkyl includes —CH 2 CH 2 CONHCH 3 ,
—CH 2 —CONHCH 2 CH 3 ; the term N,N-dialkylaminoalkyl includes —CH 2 CON(CH 3 ) 2 ; CH 2 CH 2 CON(CH 2 —CH 3 ) 2 . The tellurium based compounds that are preferred include those of the formula:
[0000]
[0000] wherein X is halogen. The preferred halogen species is chloro.
[0010] Other compounds which are based on tellurium and may be used in the practice of the invention include PhTeCl 3 , TeO 2 and TeX 4 (C 6 H 5 ) 4 P+(TeCl 3 (O 2 C 2 H 4 ))— (Z. Naturforsh, 36, 307-312 (1981). Compounds of the following structure are also included:
[0000]
[0011] Other compounds useful for the practice of invention include:
[0000]
[0000] wherein R 11 , R 12 , R 13 and R 14 are independently selected from the group consisting of hydrogen, hydroxy-alkyl of 1-5 carbons atoms, hydroxy and alkyl of 1-5 carbons atoms.
[0012] Useful dihydroxy compounds for use in the preparation of compounds of structure A or B, include those of formula I wherein R, R 1 , R 4 and R 5 are as shown in the Table:
[0000]
TABLE
(I)
R
R 1
R 4
R 5
H
H
H
H
H
Cl
H
H
H
OCH 3
H
H
H
COOCH 3
H
H
H
H
CN
H
H
CHO
H
H
H
H
COOH
H
H
CH 2 COOH
H
H
H
H
CH 2 COOCH 3
H
H
I
H
H
H
H
Br
H
H
H
CONH 2
H
H
H
CH 2 OH
H
H
COOH
H
H
[0013] Other dihydroxy compounds for use in the preparation of compounds A and B include those of formula II wherein R, R 1 , R 2 , R 3 , R 4 and R 5 are as shown in the Table:
[0000]
(II)
R
R 1
R 2
R 3
R 4
R 5
H
H
H
H
H
H
H
H
Cl
H
H
H
H
CH 2 OH
H
H
H
H
H
H
OH
H
H
H
H
H
H
CH 3
H
H
H
H
H
CH 2 Cl
H
H
H
H
H
COOH
H
H
H
H
H
CH 2 COOH
H
H
H
H
H
CHO
H
H
H
H
H
H
H
CH 2 CHO
H
H
CONH 2
H
H 2
CH 3
H
H
H
CN
H
H
H
H
H
H
CH 2 COHN 2
H
H
H
H
COOCH 3
H 3
H
H
H 3
OCH 3
H
H
H
[0014] Other dihydroxy compounds for use in making compound of formula A and B include those of formula III wherein R, R 1 , R 2 , R 3 , R 4 and R 5 are as shown in the Table.
[0000]
(III)
R
R 1
R 2
R 3
R 4
R 5
R 8
R 9
H
H
H
H
H
H
H
H
H
H
Cl
H
H
H
H
H
H
H
H
H
Br
H
H
H
H
H
OCH 3
H
H
H
H
H
H
H
CONH 2
H
H
H
H
H
H
Br
H
H
H
H
H
H
H
H
H
H
CH 2 COOH
H
H
H
H
H
Cl
Cl
H
H
H
H
H
CH 2 COOH
H
H
H
H
H
H
H
H
CH 3
H
H
H
H
H
H
CH 3
H
H
H
H
H
H
H
CH 2 Cl
H
H
H
H
H
H
H
H
H
I
H
H
H
H
H
CH 2 CN
H
H
H
H
H
H
H
H
H
H
CH 2 CH 2 OH
H
H
H
[0015] Additional dihydroxy compounds include those of formula IV wherein R, R 1 , R 2 , R 3 , R 4 and R 5 are as shown in the Table.
[0000]
(IV)
R
R 1
R 2
R 3
R 4
R 5
R 6
R 7
R 8
R 9
H
H
H
H
H
H
H
H
H
H
H
H
Cl
H
H
H
Cl
H
H
H
H
H
Cl
Cl
H
H
H
H
H
H
H
H
CONCH 3
H
H
H
Br
H
H
H
H
H
Br
H
H
H
CON(CH 3 ) 2
H
H
H
H
H
H
OCH 3
H
H
H
H
H
H
H
H
H
H
OCH 3
H
H
H
H
H
H
H
H
H
CH 2 COOH
H
H
H
H
H
H
H
COOH
H
H
H
H
H
H
H
H
CH 3
H
H
H
H
H
H
H
H
CH 3
H
H
H
H
CH 3
H
H
H
H
H
CH 2 CH 3
H
H
H
H
H
Cl
H
H
H
CH 2 CN
H
H
CH 2 OH
H
H
H
H
H
H
H
H
I
H
H
H
H
CN
H
H
CH 2 CH 2 COOH
H
H
H
H
H
H
H
H
H
H
CHO
H
H
H
H
H
H
H
H
H
H
F
H
H
H
H
H
H
[0016] Compounds of the following formula are also included:
[0000]
[0000] herein R 15 , R 16 , R 17 and R 18 are independently selected from halogen, alkyl of 1-5 carbons; aryl, acyl of 1-5 carbon hydroxyalkyl of 1-5 carbons and aminoalkyl of 1-5 carbons may be made by reacting the appropriate di, tri or tetrahalotelluride with the appropriate hydroxy compound which may be of the formula: HO—R 19 ;
wherein R 19 ; is alkyl of 1 to 5 carbons, haloalkyl of 1 to 5 carbons, aryl, alkylaryl, alkylamido of 1 to 5 carbons, alkylcarbonyl of 1 to 5 carbons, cyanoalkyl of 1 to 5 carbons, cyanoalkyl of 1 to 5 carbons, and an alkoxyalkyl of 2 to 10 carbons. Specific examples of R 16 include methyl, ethyl, n-propyl, phenyl, tolyl, amidoethyl, cyanomethyl, methyloxymethyl and CH 2 CH 2 COOH.
[0017] These compounds are described in United States Letters Patent No. 4,761,490 which is incorporated by reference. In addition, TeCl 4 ; TeBr 4 and compounds which give in aqueous solution TeO 2 preferably in the form of a complex such as for example TeO 2 complex with citric acid or ethylene glycol.
[0018] The preferred compound is ammonium trichloro (dioxoethylene-O,O′) tellurate.
Treatment of Fish
[0019] Tilapia hybrids ( Oreochromis niloticus X O. aureus ) of 100-200 g in weight were raised in the Fish Immunology & Genetics Laboratory, Bar Ilan University. Carp ( Cyprinus carpio ) of 200-350 gr were purchased from the “Mevo-Hamah” farm (Israel). The fish were kept in 400 L plastic tanks with re-circulating water system. Temperature and oxygen levels were kept constant at 26±2° C. and 4-6 ppm, respectively. The term “organic tellurium” is defined to mean any tellurium element bonded to an organic moiety, including via atoms that differ from carbon, such as oxygen.
[0020] For in-vitro studies, AS101 was supplied as PBS solution, pH 7.4, at 4° C. For in-vivo experiments, AS101 powder was dissolved in the appropriate concentration in re-circulating water.
Cell Culture
[0021] PBL (peripheral blood leukocytes) were isolated from heparinized blood on a ficoll paque bed (Amersham Bioscience) and cultured as previously reported (9). For AS101 treatments, AS101 was added directly to the cultures at final concentration of 0.025 to 25 μg/ml, preferably 0.05 to 0.5 μg/ml.
Stress Induction
[0022] Fish were subjected to air exposure stress every 60 min for 90 sec during 4 hours (10). The fish were then divided into groups of 3, each separately held in 40 L plastic containers at 28°±2° C.
Western Blot Analysis
[0023] PBL were lysed as previously reported (6). Samples were electrophoresed on 12% SDS-PAGE and blotted with anti-human-IL-10 mAb (Santa Cruz Biotechnology, Inc sc-8438) (1:660 dilution) and HRP-conjugate secondary Ab (Jackson Immuno-Research) (1:6600 dilution).
Serum IL-10L Detection
[0024] Fish blood was coagulated during 2 hours at room temperature, then centrifuged for 10 min at 1800×g. IL-10L levels were quantified in the collected sera using ELISA (Human Interleukin-10 ELISA Kit, pierce-endogen) according to manufacturer's instructions.
Stress Intensity Control
[0025] Blood samples were taken 1 hour after stress induction, sera separated by centrifugation as above and glucose levels were measured using Glucose TRINDER reagent (Sigma) according to manufacturers instructions, in a 96 microwell plate at 490 nm.
Results
[0026] AS101 effect on the intracellular IL-10L levels of tilapia cell cultures
[0027] AS101 caused significant inhibition of intracellular tilapia IL-10L synthesis. This inhibitory effect was dose-dependant and complete inhibition was achieved with 0.5 μg/ml AS101 ( FIG. 1 ).
[0028] Influence of extensive stress on serum IL-10L levels Serum IL-10L levels were measured prior to stress induction and at different intervals of time (1, 5, 6, 8, 16, 20, and 24 Hrs) following stress induction. Significant IL-10L increase (p=0.001) started at 1 hour post stress, peaked on hours 8-16 and underwent significant decrease (p=0.006) afterwards ( FIG. 2 ). AS101 effect on stress induced serum IL-10L and glucose levels
[0029] The maximal AS101 effect on IL-10L level (decrease from 719 to 209 pg/ml) was obtained 2 hours post-stressed following bath immersion in a 20-ppm water solution of this compound. AS101 treatment, while affecting IL-10L, had no effect on blood glucose levels which remained high (190 mg/dl±0.12) as in control stressed fish, ( FIG. 3 )
[0030] AS101 effect on stressed fish infected with Aeromonas salmonicida
[0031] Stress induced fish that were immersed in soluble AS101 after being exposed to Aeromonas salmonicida had significantly lower number of wounds per fish ( FIG. 4 ) and higher rate of survival ( FIG. 5 ) in contrast to stressed fish infected with the bacteria and not treated with AS101. AS101 inhibits tilapia intracellular IL-10L in vitro in a dose dependant manner. The possibility that the inhibition was due to cell toxicity, was examined Blue staining, and did not show elevated cell death beyond control in all AS101 doses, indicating that AS101 has no which were taken 6 hours after stress induction and bath immersion in different AS101 concentrations showed a significant IL-10L decrease, mainly with AS101 dose of 20 μg/ml which was the most efficient. These results show that AS101 reached the fish blood probably by penetrating through the skin, the gills or the gut epithelia. Interestingly, both IL-10L and glucose, which showed significant blood elevation following stress induction, only IL-10L, was down regulated by the AS101 treatment.
[0032] These results suggest that the protective role of AS101 against Aeromonas salmonicida infections in stressed goldfish involves AS101 mediated IL-10L inhibition, emphasizing it as an effective agent against stress-induced immune suppression.
[0033] References which are incorporated into this application:
[1] Takashi Y, Teruyuki N. Interaction between the endocrine and immune Systems in Fish. Int Rev Cytol. 220:35-92; 2002 [2] Jun Z, Melody S C, Secombes C J. Characterisation, expression and promoter analysis of an interleukin 10 homologue in the pufferfish ( Fugu rubripes ). 55(5): 325-35; August 2003 [3] Sredni B, Caspi R R, Klein A, Kalechman Y, Danziger Y, Ben Ya'akov, M Tamari T, Shalit F, Albeck M. A new immunomodulating compound (AS-101) with potential therapeutic application. Nature. 330(6144): 173-176; November 1987 [4] Strassmann G, Kambayashi T, Jacob C O, Sredni B. The immunomodulator AS-101 inhibits IL-10 release and augments TNF alpha and IL-1 alpha release by mouse and human mononuclear phagocytes. Cell. Immunol. 176: 180; 1997. [5] Kalechman Y, Zuloff A, Albeck M, Strassmann G, Sredni B. Role of endogenous cytokines secretion in radioprotection conferred by the immunomodulator ammonium trichloro (dioxyethylene- 0 - 0 ′) tellurate Blood. 85: 1555; 1995 [6] Kalechman Y, Longo D L, Catane R, Shani A, Albeck M, Sredni B. Synergistic anti-tumoral effect of paclitaxel (Taxol)+AS101 in a murine model of B16 melanoma: association with ras-dependent signal-transduction pathways Int. J. cancer. 86: 281; 2000 [7] Elenkov I J and Chrousos G P. Stress Hormones, Proinflammatory and antiinflammatory Cytokines, and Autoimmunity. Ann. N.Y. Acad. Sci. 966: 290-303; 2002 [8] Akdis C A, Blaser K. Mechanisms of interleukin-10-mediated immunesuppression. 103 (2): 131-6; June 2001 [9] Rosenberg-Wiser S, and Avtalion R R. The cells involved in the immune response of fish. III. Culture requirement for phytohemagglutinin stimulated peripheral carp lymphocytes. Devel. Comp. Immunol. 6:693-702; 1982 [10] Melamed O, Timan B, Avtalion R R and Noga E J. Design of a stress model in the hybrid bass ( Morone saxatilis x Morone Chrysops ). Isr. J. Aguac - Bamidgeh. 51(1): 10-16; 1999 | A method for the direct or adjunct treatment of bacterial or fungal infections in fish and crustaceans including shell fish which is based on providing an effective amount of an organic tellurium compound in an aqueous environment to which said fish or crustaceans are exposed. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] Not applicable.
FIELD OF THE INVENTION
[0002] The field of the invention relates to medical prosthesis and, more particularly, to those medical prostheses used for breast, testicular, lips or buttocks.
BACKGROUND OF THE INVENTION
[0003] Over the years, various implants have been designed to resemble the feel of a natural breast, or the shape and size of a natural breast. Breast augmentation surgeries have been performed in accordance with a plurality of procedures for decades by medical professionals in this field. In general, these procedures have consisted of inserting a singular sac into each breast and then volumizing the cavity with “fillers” such as silicone, saline, aqueous sugar solutions, aqueous solutions consisting of polyethylene glycol and other chemically inert, non-inflammatory, non-allergenic, and non-carcinogenic compositions.
[0004] Silicone fillers in general provide more viscous characteristics and thus more closely resemble the look and feel of a natural breast. However, silicone compounds remain slightly reactive when implanted into one's body and as a result threaten the vitality of the body in the event the silicone implant leaks or ruptures. Under such circumstances, the silicone is capable of moving freely throughout the body and collecting in major bodily organs. The presence of free silicone in the body has incited autoimmune responses in many patients ultimately resulting in the patient's body reaching a severe debilitated state.
[0005] Saline implants have provided additional flexibility to the size and symmetry of the breast (e.g., the amount of fluid injected will affect how large the implant or how small the implant would be). However, flexibility to change the size of the breast with time is not simple in these conventional implants and replacement of the implant may be necessary if a change is desired. Furthermore, the weight of the implant becomes an issue when electing to go with a larger implant. The additional weight resulting from the implantation of the larger implant presents an undue burden on the recipient and ultimately may cause ailments in the user (i.e., increased back pain resulting from the weight of a larger breast implant).
SUMMARY OF THE INVENTION
[0006] An implant comprises a biologically proven inert material that encases compartments of fluid and/or gas to form a prosthesis of varied characteristics. The prosthesis contains at least one micro-compartment in a hierarchical layered formation each of which contain filler consisting of liquid, air, gas, gel or combination thereof. The amount of filler injected into each micro-compartment varies depending on the size and shape that the receiving individual seeks to achieve. Moreover, the removable nature of the micro-compartments facilitate one's ability to customize the prosthesis (i.e., if a smaller prosthesis is warranted, a medical examiner may extract filler from the prosthesis using a medical instrument, or even remove the micro-compartments to change the specific gravity of the prosthesis). Modifying the number of micro-compartments and amount of filler in the micro-compartments helps the receiving individual achieve an implant custom to their specific needs.
[0007] The customizable prosthesis comprises a flexible outer shell made of soft Poly(methyl 2-methlypropenoate) gel (hereinafter “PMMA”) having at least one flexible filler tube for facilitating the traversal of injected fluids. Within the cavity of the outer shell, there is at least one micro-compartment arranged in a hierarchical layered scheme. The micro-compartments may be filled with fluids and inert gases or combination thereof. After the prosthesis has been placed into the surgically prepared implant site, the filler tube or tubes are drawn to a point that terminates adjacent to the arm pit. The input ports, through which fillers are injected, may be buried under the skin in the vicinity of the armpit at the end of the procedure. These input ports are accessible in the future for the purpose of modifying the structural characteristics and qualities of the prosthesis. For example, as the individual gets older, they may want to modify the size and shape of breast implant, therefore a lighter breast may be achieved by injecting multiple micro-compartment layers comprised of inert-gases behind the first micro-compartment, which can be comprised of a fluid-like solution. Injecting multiple micro-compartments with an inert gas creates an implant that possesses a lower specific gravity than an implant made of purely fluid fillers. As stated above, the injected fillers can be made of saline, silicone gel, PMMA gel, or other fluids and/or gases that are biologically tolerated (e.g., chemically inert compositions). Moreover, the injected filler may further comprise a fluorescent agent to serve as a visual aide for medical professionals when examining the implant in the dark under blue light (e.g., Ultra Violet Light).
[0008] The fluorescent agent creates an incentive in the receiving individual to periodically follow up with their physician for check-ups because the examining physician will be able to determine whether the implant has shifted from the implant site or whether any leaks are present when viewed under blue light. The fluorescent agent found in the filler makes it easier to for a medical professional to examine the structure of the prosthesis as a whole with minimal invasiveness. Moreover, at any time after the surgery, the size, shape and/or consistency of the prosthesis may be altered via a simple procedure conducted at an office visit. A medical professional can make a small incision after locating the filler tube under blue light and simply inflate or deflate the prosthesis with a filler until the desired shape, size, weight and/or consistency of the individual is achieved.
[0009] The soft PMMA materials have been shown to be biologically inert and have been proven to lack any adverse reactions within the body. PMMA has been a well respected and useful compound for those in the field of Ophthalmology. The physical properties (e.g., durable, light weight, and memory-like qualities) and chemical properties (e.g., inert compound) of PMMA have contributed to the ongoing use by medical professionals today. Today, the soft PMMA materials can be manufactured to conform to the various shapes and firmness values desired by the customer. The design of multiple micro-compartments implanted within the cavity of the outer shell of the prosthesis serves a novel feature in decreasing the total weight of the prosthesis, independent of its size, while simultaneously preserving the qualities of a natural breast. Controlling the specific gravity of the prosthesis is a major breakthrough in the field of cosmetic surgery because the recipient may modify the prosthesis as they get older. For example, as women age the glandular tissues of the breast start to breakdown, ultimately accounting for the cause to ptosis of the breasts. Other relevant factors leading to ptosis of the breasts include a women's body mass index (hereinafter “BMI”), number of pregnancies, whether they have ever breast fed, family history and overall weight. However, the apparatus and method of implementing a prosthesis with customizable features resolves the ptosis of the breasts dilemma. An individual with the implant may at anytime decrease the amount of aqueous filler in the first micro-compartment layer and increase the number of micro-compartment layers filled with inert gases as a means to decrease the specific gravity of the breast. Light weight and more supportive breasts are derived from decreasing the specific gravity of the prosthesis. As such, the present invention facilitates a user's ability to reduce their breast size, increase their breast size and “lift” their breasts via a minimally invasive procedure.
[0010] These and other objects, features, and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] These and other features and advantages of the present invention will be better and more completely understood by referring to the following detailed description of example non-limiting embodiments in conjunction with the drawings, of which:
[0012] FIG. 1 illustrates a perspective view of a customizable prosthesis in accordance with one or more embodiments of the present invention.
[0013] FIG. 2 illustrates a perspective view of the micro-compartments of a customizable prosthesis in accordance with one or more embodiments of the present invention.
DETAILED DESCRIPTION
[0014] Various aspects and embodiments of the present invention will now be described in detail with reference to the accompanying figures. Certain terminology is used herein for convenience only and is not to be taken as a limitation on the present disclosure. The terminology includes the words specifically mentioned, derivatives thereof and words of similar import. The embodiments illustrated below are not intended to be exhaustive or to limit the disclosure to the precise form disclosed. These embodiments are chosen and described to best explain the principle of the disclosure and its application and practical use and to enable others skilled in the art to best utilize the disclosure.
[0015] FIG. 1 illustrates a perspective view of a customizable prosthesis 100 designed for surgical implantation into the soft tissue of an individual. Prosthesis 100 is further comprised of flexible implant tube 102 , injectable port 104 , outer shell 106 and prosthesis cavity 108 .
[0016] Prosthesis 100 is surgically implanted into an individual at a small localized incision via a medical instrument. Outer shell 106 of prosthesis 100 is formulated out of a polymer (e.g., PMMA) that possesses memory-like and ductile qualities. The structural qualities embraced by outer shell 106 provide the surgeon with several alternative procedures in which to implant the prosthesis (e.g., prosthesis may be implant via a localized incision; prosthesis may be implanted via a medical instrument possessing an injectable means). Upon implantation of prosthesis 100 , the volume of prosthesis 100 may be modified in accordance with the patient's specifications. For example, a patient may increase the size of prosthesis 100 via an influx of filler (e.g., saline, PMMA, inert gas, silicone, etc.) injected by a medical instrument at injectable port 104 . The filler then traverses along implant tube 102 and empties in prosthesis cavity 108 . Alternatively, a patient may decrease the size of prosthesis 100 by retracting filler from prosthesis cavity 108 . A single filler or combination thereof may contribute to the volumization of prosthesis 100 . Prostheses cavity 108 may consist of a singular inflatable compartment or a plurality of micro-compartments arranged in a hierarchical layered scheme wherein each compartment possesses elastic and memory-like structural characteristics.
[0017] Prosthesis 100 is not limited to purely augmentation mammoplasty procedures. An individual may have prosthesis 100 implanted for a plurality of cosmetic procedures including but not limited to lip enhancements, buttock augmentation and testicular implants. The procedures relating to the implant of prosthesis 100 is very similar regardless of the location of the implant itself. A localized incision is made, prosthesis 100 is then implanted at the site of the localized incision, prosthesis 100 is then maneuvered into the proper position, prosthesis fluid is injected by an individual at injectable port 104 via a medical instrument to achieve the desired size, shape and/or firmness and then injectable port 104 is clamped and stowed within the tissue of the individual upon completion. As described above, the filler's injected into prosthesis 100 for augmentation mammoplasty procedures may remain the same for every other cosmetic surgery performed using the described materials.
[0018] FIG. 2 illustrates a perspective view of micro-compartments 204 incorporated within customizable prosthesis 200 . Micro-compartments 204 are designed to achieve the ideal shape and weight of prosthesis 200 Like outer shell 106 , micro-compartments 204 are manufactured from the polymer PMMA. Outer shell 206 is further comprised of at least one flexible implant tube 202 and corresponding injectable port wherein at least one removable micro-compartment 204 extends outward therefrom. Micro-compartments 204 are arranged in a hierarchical layered scheme therefore providing the recipient with a customizable prosthesis. For example, micro-compartment 204 - 1 represents the first layer of the layering scheme attributed to prosthesis 200 . Micro-compartment 204 - 1 is volumized by an aqueous filler (e.g., saline, PMMA, silicone, aqueous solution, etc.) in order to provide the recipient with the feel and look of a natural breast. Micro-compartments 204 - 2 . . . 204 - 10 are then filled with an inert gas to reduce the specific gravity of prosthesis 200 as a whole.
[0019] Reducing the specific gravity of prosthesis 200 presents an entirely new novelty in the field of cosmetic surgery. For example, a light weight, natural looking and feeling prosthesis may be implanted into an individual without the unnecessary weight constraints imposed on by today's outdated technology. As described above, the hierarchical layered scheme of micro-compartments 204 - 1 . . . 204 - 10 contributes to the phenomena of reducing the specific gravity of prosthesis 200 . Similar to the description of prosthesis 100 , prosthesis 200 may be modified at any time. For example, a woman who initially received large breast implants may reduce the size of the implant as they get older in order to prevent ptosis of the breast. Implant tube 202 and injectable port 208 is clamped and stowed within the tissue of the individual upon completion. However, a medical professional can make a small incision after locating implant tube 202 under blue light and simply volumize or devolumize prosthesis 200 by injecting a liquid and/or gas until the desired shape, size, weight and/or consistency of the individual is achieved.
[0020] An illuminating agent (e.g., fluorescein) is incorporated within implant tube 202 of prosthesis 200 . The illuminating agent creates an incentive in the receiving individual to periodically follow up with their physician for check-ups because the examining physician will be able to determine whether prosthesis 200 has shifted from the implant site or whether any leaks are present when viewed under blue light. Furthermore, the illuminating agent makes it easier for a medical professional to examine the structure of prosthesis 200 as a whole with minimal invasiveness. A medical professional can make a small incision after locating filler tube 202 while examining under blue light and simply inflate or deflate micro-compartments 204 - 1 . . . 204 - 10 of prosthesis 200 with a liquid and/or gas until the desired shape, size, weight and/or consistency of the individual is achieved.
[0021] It should again be emphasized that the above-described embodiments of the invention are presented for purposes of illustration only. Many variations may be made in the particular arrangements shown. For example, although described in the context of particular augmentation mammoplasty procedures, the techniques are applicable to a wide variety of other types of prosthesis implantations. In addition, any simplifying assumptions made above in the course of describing the illustrative embodiments should also be viewed as exemplary rather than as requirements or limitations of the invention. Numerous other alternative embodiments within the scope of the appended claims will be readily apparent to those skilled in the art. | The present invention relates to a customizable prosthesis, for instance a breast prosthesis, comprised of an outer shell, removable micro-compartments and flexible filling tubes formulated out of soft Poly (methyl 2-methylpropenoate) gel, wherein the removable micro-compartments of the prosthesis are arranged in a hierarchical layering scheme to create a prosthesis capable of undergoing modifications quickly, easily and with minimal invasiveness, while retaining a prosthesis with low specific gravity. | 0 |
BACKGROUND AND MATERIAL DISCLOSURE STATEMENT
The present invention relates to an imaging system using coherent light radiation to expose a layered member in an image configuration and, more particularly, to a method for forming the imaging member so as to reduce optical interference occurring within said member which results in a plywooding type of defect in output prints.
There are numerous applications in the electrophotographic art wherein a coherent beam of radiation, typically from a helium-neon or diode laser, is modulated by an input image data signal. The modulated beam is directed (scanned) across the surface of a photosensitive medium. The medium can be, for example, a photoreceptor drum or belt in a xerographic printer, a photosensor CCD array, or a photosensitive film. Certain classes of photosensitive medium which can be characterized as "layered photoreceptors" have at least a partially transparent photosensitive layer overlying a conductive ground plane. A problem inherent in using these layered photoreceptors, depending upon the physical characteristics, is an interference effectively created by two dominant reflections of the incident coherent light on the surface of the photoreceptor; e.g. a first reflection from the top surface and a second reflection from the bottom surface of the relatively opaque conductive ground plane. This condition is shown in FIG. 1: a coherent beam is incident on a layered photoreceptor 6 comprising a charge transport layer 7, charge generator layer 8, and a ground plane 9. The interference effects can be explained by following two typical rays of the incident illumination. The two dominant reflections of a typical ray 1, are from the top surface of layer 7, ray A, and from the top surface of ground plane 9, ray C. The transmitted portion of ray C, ray E, combines with the reflected portion of ray 2, ray F, to form ray 3. Depending on the optical path difference as determined by the thickness and index of refraction of layer 7, the interference of rays E and F can be constructive or destructive when they combine to form ray 3. The transmitted portion of ray 2, ray G, combines with the reflected portion of ray C, ray D, and the interference of these two rays determines the light energy delivered to the generator layer 8. When the thickness is such that rays E and F undergo constructive interference, more light is reflected from the surface than average, and there will be destructive interference between rays D and G, delivering less light to generator layer 8 than the average illumination. when the transport layer 7 thickness is such that reflection is a minimum, the transmission into layer 8 will be a maximum. The thickness of practical transport layers varies by several wavelengths of light so that all possible interference conditions exist within a square inch of surface. This spatial variation in transmission of the top transparent layer 7 is equivalent to a spatial exposure variation of generator layer 8. This spatial exposure variation present in the image formed on the photoreceptor becomes manifest in the output copy derived from the exposed photoreceptor. The output copy exhibits a pattern of light and dark interference fringes which look like the grains on a sheet of plywood, hence the term "plywood effect" is generally applied to this problem.
In the prior art, various techniques are known for modifying the structure of the imaging member to reduce the second dominant reflection from the imaging member ground plane. U.S. Pat. No. 4,618,552 and copending application, U.S. Ser. No. 07/546,990, filed on Jul. 2, 1990 now U.S. Pat. No. 5,096,792, describe methods of roughening the surface of the ground plane to create a diffuse reflection of the light reflected therefrom. U.S. Ser. No. 07/541,655, filed on Jun. 21, 1990, now abandoned, discloses a roughening of the PET substrate upon which the ground plane is formed with the roughening replicated into the ground plane. U.S. Ser. No. 07/523,639, filed on May 15, 1990, now U.S. Pat. No. 5,051,328, and U.S. Ser. No. 07/552,200, filed on Jul. 13, 1990, now U.S. Pat. No. 5,139,907 disclose forming the ground plane or a layer over the ground plane, respectively, of a transparent conductive material. U.S. Ser. No. 07/646,117, filed on Jan. 28, 1991, now U.S. Pat. No. 5,069,758, discloses an electroforming process for the imaging member ground plane, which results in a ground plane with a smooth, dull surface.
The present invention is directed towards eliminating the reflections from the ground plane by forming the imaging member with a conductive ground plane with a black nickel surface. The black surface absorbs, rather than reflects, the incident light. Since the light absorbs, secondary reflections which create cross-talk among pixels at the member surface are eliminated. This eliminates a problem which was present in prior art systems which taught methods of diffusely reflecting light from the ground plane surface. Also present in the diffusely reflecting prior art concepts, for each wavelength of incident light, there was an optimum roughness to the diffusely reflecting surface. The black belt of the present invention absorbs all wavelengths; hence enabling a wider manufacturing latitude. More particularly, the present invention is directed towards an improved photosensitive imaging member having at least a conductive ground plane with an overlying charge transport and charge generator layers, the improvement wherein said ground plane has a smooth black finish which absorbs all wavelengths of light incident thereon.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows coherent light incident upon a prior art layered photosensitive medium leading to reflections internal to the medium.
FIG. 2 is a schematic representation of an optical system incorporating a coherent light source to scan a light beam across a photoreceptor modified to reduce the interference effect according to the present invention.
FIG. 3 shows a cross-sectional view of the photoreceptor of FIG. 2.
DESCRIPTION OF THE INVENTION
FIG. 2 shows an imaging system 10 wherein a laser 12 produces a coherent output which is scanned across photoreceptor 14. FIG. 3 is a cross sectional view of the photoreceptor of FIG. 2. Laser 12 is, for this embodiment, a helium neon laser with a characteristic wavelength of 0.63 micrometer, but may be, for example, an Al Ga As Laser diode with a characteristic wavelength of 0.78 micrometers. In response to video signal information representing the information to be printed or copied, the laser is driven in order to provide a modulated light output beam 16. The laser output, whether gas or laser diode, comprises light which is polarized parallel to the plane of incidence. Either polarization is possible and may be used depending on circumstances. Flat field collector and objective lens 18 and 20, respectively, are positioned in the optical path between laser 12 and light beam reflecting scanning device 22. In a preferred embodiment, device 22 is a multifaceted mirror polygon driven by motor 23, as shown. Flat field collector lens 18 collimates the diverging light beam 16 and field objective lens 20 causes the collected beam to be focused onto photoreceptor 14, after reflection from polygon 22. Photoreceptor 14 is a layered photoreceptor, but one which, in the prior art, has the structure shown in FIG. 3 and has been modified according to the invention shown in FIG. 4.
Referring to FIG. 3, photoreceptor 14 is a layered photoreceptor which includes a conductive ground plane 24 having a black surface 24A and formed by an electroforming process according to the present invention. The photoreceptor also includes a dielectric substrate 25, (typically polyethylene terephthalate (PET)), a charge generating layer 26, and a semitransparent charge transport layer 28. A blocking layer (not shown) is provided at the interface of ground plane 24 and charge generating layer 26 to trap charge carriers. A photoreceptor of this type (with a conventional ground plane 24) is disclosed in U.S. Pat. No. 4,588,667, whose contents are hereby incorporated by reference. The black surface 24A absorbs the light rays 16 penetrating through layers 28 and 26, thus eliminating the secondary reflections which create the interference pattern at the member surface.
Ground plane 24 is formed by an electroforming process in which a conventional electroforming technique, such as disclosed in U.S. Pat. No. 3,844,906, whose contents are hereby incorporated by reference, is modified in order to control the forming conditions, to create a surface having a black finish. In a preferred embodiment, ground plane 24 is an electroconductive (nickel) flexible seamless belt. The belt is electrodeposited on a cylindrically shaped form or mandrel which is suspended in an electrolytic bath (nickel sulfamate solution). A DC potential is applied between the rotating mandrel cathode and the donor metallic nickel anode for a sufficient period of time to effect electrodeposition of nickel on the mandrel to a predetermined thickness (0.0010 to 0.010 inch are typical thicknesses). Following formation of the belt substrate, the electroform is modified to make it slightly anodic (0.050 V to 0.450 V versus SCE) rather than the normal cathodic and a black surface oxide is formed. Thus, the black finish is advantageously formed in situ. Upon completion of the electroforming process, the mandrel and the nickel belt formed thereon are transferred to a cooling zone whereby the belt, which exhibits a different coefficient of thermal expansion than the mandrel, can be readily separated from the mandrel. The surface roughness of the belt is controlled to provide a surface smoothness (or roughness) of preferably 0.5 to 20.0μ inch RMS. The photosensitive layers (charge generating layer 26 and charge transport layer 28) are then deposited on ground plane 24 and substrate 25 using conventional techniques known in the art. The photoreceptor 14, when used, for example, in the ROS system shown in FIG. 3, exhibits virtually none of the spectral exposure variations which would otherwise have been caused by reflection from the ground plane since the light reaching the ground plane is absorbed by the black oxide finish.
The following examples are provided for forming a ground plane with a black surface. In a first example, a nickel substrate is formed with the following constituents and operating parameters:
EXAMPLE 1
Nickel Substrate
Major Electrolyte Constituents:
Nickel Sulfamate--as Ni +2 , 11 oz/gal. (82.5 g/L.)
Chloride--as NiCl 2 .6H 2 O, 2 oz/gal. (15 g/L.)
Boric Acid--5 oz/gal. (37.5 g/L.)
pH--3.95-4.05 at 23° C.
Surface Tension--at 136° F., 32-37 d/cm using Sodium Lauryl Sulfate (about 0.00525 g/L.).
Sacchrin--25-30 mg/L., as Sodium Benzosulfimide dihydrate
Impurities:
Azodisulfonate--5-10 mg/L.
Copper--5 mg/L.
Iron--25 mg/L.
MBSA--(2-Methyl Benzene Sulfonamide)-5-10 mg/L.
Sodium--1 gm/L.
Sulfate--5 g/L.
Operating Parameters:
Agitation rate--5 Linear ft/sec solution flow over the cathode surface.
Cathode (Mandrel)--Current Density, 225 ASF (amps per square foot)
Ramp Rise--0 to operating amps in 2 sec. ±1 sec.
Anode--Sulfur Depolarized Nickel and Carbonyl Nickel
Anode to Cathode Ratio--1.2:1
Deposit Thickness--0.0045 inches
Mandrel--Chromium plated Aluminum--8 to 15 micro inch RMS.
Temperature--62° C.
After the required thickness is obtained, the electroform is made slightly anodic (0.220 V. vs. a SCE for 30 seconds) and a black oxide is formed in situ. Other nickel electroforming conditions will often require a different anodic voltage to obtain the desired uniformly colored black finish.
EXAMPLE 2
Alternatively, the electroform can be removed from the system above or from other electroforming systems (which are well known those skilled in the art) before the anodic treatment and be subsequently made to have a black nonreflective surface by using a black nickel bath with the following constituents:
Major Electrolyte Constituents:
Nickel sulfate 75 g/L.
Nickel ammonium sulfate 45 g/L.
Zinc sulfate 37.5 g/L.
Sodium thiocyanate 15 g/L.
Room temperature
pH 5.6-5.9
Current density 0.5-2.0 amp/ft 2
EXAMPLE 3
A nickel substrate is formed as in Example 1. A black oxide finish is formed in a new bath, with the following constituents:
Nickel chloride 75 g/L.
Ammonium chloride 30 g/L.
Sodium thiocyanate 15 g/L.
Zinc chloride 30 g/L.
Room temperature
pH 5.0
Current density 1.5 amp/ft 2
Various other metals could be used instead of nickel: e.g. brass or copper. An aluminum substrate with a black surface could be formed by an anodization process. A black chromium surfaced belt can be obtained by forming a substrate, then exposing that substrate to a black chromium bath. Two examples are provided as shown in Examples 4 and 5.
EXAMPLE 4
Chromic acid 248-300 g/L.
Acetic acid 212 g/L.
Barium acetate 7.5 g/L.
Temperature 90°-115° F.
Current density 40-90 amp/ft 2
EXAMPLE 5
Chromic acid 248 g/L.
Fluosilic acid 0.25 g/L.
Temperature 80°-95° F.
Current density 150-450 amp/ft 2
While the invention has been described with reference to the structure disclosed, it will be appreciated that numerous changes and modifications are likely to occur to those skilled in the art, and it is intended to cover all changes and modifications which fall within the true spirit and scope of the invention. | A layered photosensitive imaging member is modified to reduce the effects of interference within the member caused by reflections from coherent light incident on a base ground plane. The modification described is to form the ground plane surface by an electroforming process which leaves the surface with a black finish. Light incident on the ground plane is absorbed, eliminating the reflections which contribute to the interference effect at the imaging member surface. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation-in-part application of co-pending, commonly owned U.S. patent application Ser. No. 09/861,219, filed May 18, 2001, which claims priority from provisional application U.S. Ser. No. 60/206,060, filed May 19, 2000, now expired, and is a continuation-in-part of co-pending, commonly owned U.S. patent application Ser. No. 09/716,146, filed Nov. 17, 2000 and is a continuation-in-part of co-pending, commonly owned U.S. patent application Ser. No. 13/103,576, filed May 9, 2011, each of which is hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] The invention relates to methods and apparatus for manufacturing medical devices, including endoluminal stents, wherein the medical device has at least one groove on at least a first surface of the device that is generally in contact with endothelial tissue and blood flow when implanted within the body. A drug-eluting polymer is disposed within the groove, but does not otherwise cover the surface of the endoluminal stent, the groove having a drug-eluting polymer treated to promote the migration of endothelial cells onto the inner surface of the intravascular stent.
[0003] Various types of intravascular or endoluminal stents have been used in recent years. An intravascular stent generally refers to a device used for the support of living tissue during the healing phase, including the support of internal structures. Intravascular stents, or stents, placed endoluminally, as by use of a catheter device, have been demonstrated to be highly efficacious in initially restoring patency to sites of vascular occlusion. Intravascular stents, or stents, may be of the balloon-expandable type, such as those of U.S. Pat. Nos. 4,733,665; 5,102,417; or 5,195,984, which are distributed by Johnson & Johnson Interventional Systems, of Warren, N.J., as the PALMAZ and the PALMAZ-SCHATZ balloon-expandable stents or balloon expandable stents of other manufacturers, as are known in the art. Other types of intravascular stents are known as self-expanding stents, such as Nitinol coil stents or self-expanding stents made of stainless steel wire formed into a zigzag tubular configuration.
[0004] Intravascular stents are used, in general, as a mechanical means to solve the most common problems of percutaneous balloon angioplasty, such as elastic recoil and intimal dissection. One problem intraluminal stent placement shares with other revascularization procedures, including bypass surgery and balloon angioplasty, is restenosis of the artery. An important factor contributing to this possible reocclusion at the site of stent placement is injury to, and loss of, the natural nonthrombogenic lining of the arterial lumen, the endothelium. Loss of the endothelium, exposing the thrombogenic arterial wall matrix proteins, along with the generally thrombogenic nature of prosthetic materials, initiates platelet deposition and activation of the coagulation cascade. Depending on a multitude of factors, such as activity of the fibrinolytic system, the use of anticoagulants, and the nature of the lesion substrate, the result of this process may range from a small mural to an occlusive thrombus. Secondly, loss of the endothelium at the interventional site may be critical to the development and extent of eventual intimal hyperplasia at the site. Previous studies have demonstrated that the presence of an intact endothelial layer at an injured arterial site can significantly inhibit the extent of smooth muscle cell-related intimal hyperplasia. Rapid re-endothelialization of the arterial wall, as well as endothelialization of the prosthetic surface, or inner surface of the stent, are therefore critical for the prevention of low-flow thrombosis and for continued patency. Unless endothelial cells from another source are somehow introduced and seeded at the site, coverage of an injured area of endothelium is achieved primarily, at least initially, by migration of endothelial cells from adjacent arterial areas of intact endothelium.
[0005] Those skilled in the art will understand that the term “intravascular stent” is intended to mean a stent that is placed within the body's vascular system. It will also be understood that the term “endoluminal stent” is intended to mean a stent that is placed within a body lumen. The vascular system being luminal, the term “endoluminal” is understood to encompass “intravascular” but not the reverse. While the present invention is described with specific reference to intravascular stents, one skilled in the art will understand that endoluminal stents are also contemplated as being within the scope of the invention.
[0006] Although an in vitro biological coating to a stent in the form of seeded endothelial cells on metal stents has been previously proposed, there are believed to be serious logistic problems related to live-cell seeding, which may prove to be insurmountable. Thus, it would be advantageous to increase the rate at which endothelial cells from adjacent arterial areas of intact endothelium migrate upon the inner surface of the stent exposed to the flow of blood through the artery. At present, most intravascular stents are manufactured of stainless steel and such stents become embedded in the arterial wall by tissue growth weeks to months after placement. This favorable outcome occurs consistently with any stent design, provided it has a reasonably low metal surface and does not obstruct the fluid, or blood, flow through the artery. Furthermore, because of the fluid dynamics along the inner arterial walls caused by blood pumping through the arteries, along with the blood/endothelium interface itself, it has been desired that the stents have a very smooth surface to facilitate migration of endothelial cells onto the surface of the stent. In fact, it has been reported that smoothness of the stent surface after expansion is crucial to the biocompatibility of a stent, and thus, any surface topography other than smooth is not desired. Christoph Hehriein, et. al., Influence of Surface Texture and Charge On the Biocompatibility of Endovascular Stents, Coronary Artery Disease, Vol. 6, pages 581-586(1995). After the stent has been coated with serum proteins, the endothelium grows over the fibrin-coated metal surface on the inner surface of the stent until a continuous endothelial layer covers the stent surface, in days to weeks. Endothelium renders the thrombogenic metal surface protected from thrombus deposition, which is likely to form with slow or turbulent flow. At present, all intravascular stents made of stainless steel, or other alloys or metals, are provided with an extremely smooth surface finish, such as is usually obtained by electropolishing the metallic stent surfaces. Although presently known intravascular stents, specific including the PALMAZ and the PALMAZ-SCHATZ balloon-expandable stents have been demonstrated to be successful in the treatment of coronary disease, as an adjunct to balloon angioplasty, intravascular stents could be even more successful and efficacious, if the rate and/or speed of endothelial cell migration onto the inner surface of the stent could be increased. It is believed that providing at least one groove disposed in the inner surface of a stent increases the rate of migration of endothelial cells upon the inner surface of the stent after it has been implanted. Accordingly, the art has sought methods and apparatus for manufacturing an intravascular stent with at least one groove disposed in the inner surface of the stent.
[0007] The present invention relates generally to an implantable device for in vivo delivery of bioactive compounds. The present invention provides an implantable structural material having a three-dimensional conformation suitable for loading a bioactive agent into the structural material, implanting the structural material in vivo and releasing the bioactive agent from the structural agent to deliver a pharmacologically acceptable level of the bioactive agent to an internal region of a body. More particularly, the present invention relates to an implantable medical device, such as an endoluminal stent, stent-graft, graft, valves, filters, occluders, osteal implant or the like, having cavitated regions with micropores that communicate a bioactive agent from the cavity to an area external the stent.
[0008] The present invention may be used for any indication where it is desirable to deliver a bioactive agent to a local situs within a body over a period of time. For example, the present invention may be used in treating vascular occlusive disease, disorders or vascular injury, as an implantable contraceptive for delivery of a contraceptive agent delivered intrauterine or subcutaneously, to carry an anti-neoplastic agent or radioactive agent and implanted within or adjacent to a tumor, such as to treat prostate cancer, for time-mediated delivery of immunosuppresents, antiviral or antibiotic agents for treating of autoimmune disorders such as transplantation rejection or acquired immune disorders such as HIV, or to treat implant or non-implant-related inflammation or infections such as endocarditis.
[0009] Occlusive diseases, disorders or trauma cause patent body lumens to narrow and restrict the flow or passage of fluid or materials through the body lumen. One example of occlusive disease is arteriosclerosis in which portions of blood vessels become occluded by the gradual build-up of arteriosclerotic plaque, this process is also known as stenosis. When vascular stenosis results in the functional occlusion of a blood vessel the vessel must be returned to its patent condition. Conventional therapies for treatment of occluded body lumens include dilatation of the body lumen using bioactive agents, such as tissue plasminogen activator (TPA) or vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) gene transfers which have improved blood flow and collateral development in ischemic limb and myocardium (S. Yla-Herttuala, Cardiovascular gene therapy, Lancet, Jan. 15, 2000), surgical intervention to remove the blockage, replacement of the blocked segment with a new segment of endogenous or exogenous graft tissue, or the use of a catheter-mounted device such as a balloon catheter to dilate the body lumen or an artherectomy catheter to remove occlusive material. The dilation of a blood vessel with a balloon catheter is called percutaneous transluminal angioplasty. During angioplasty, a balloon catheter in a deflated state is inserted within an occluded segment of a blood vessel and is inflated and deflated a number of times to expand the vessel. Due to the inflation of the balloon catheter, the plaque formed on the vessel walls cracks and the vessel expands to allow increased blood flow through the vessel.
[0010] In approximately sixty percent of angioplasty cases, the blood vessel remains patent. However, the restenosis rate of approximately forty percent is unacceptably high. Endoluminal stents of a wide variety of materials, properties and configurations have been used post-angioplasty in order to prevent restenosis and loss of patency in the vessel.
[0011] While the use of endoluminal stents has successfully decreased the rate of restenosis in angioplasty patients, it has been found that a significant restenosis rate continues to exist even with the use of endoluminal stents. It is generally believed that the post-stenting restenosis rate is due, in major part, to a failure of the endothelial layer to regrow over the stent and the incidence of smooth muscle cell-related neointimal growth on the luminal surfaces of the stent. Injury to the endothelium, the natural nonthrombogenic lining of the arterial lumen, is a significant factor contributing to restenosis at the situs of a stent. Endothelial loss exposes thrombogenic arterial wall proteins, which, along with the generally thrombogenic nature of many prosthetic materials, such as stainless steel, titanium, tantalum, Nitinol, etc. customarily used in manufacturing stents, initiates platelet deposition and activation of the coagulation cascade, which results in thrombus formation, ranging from partial covering of the luminal surface of the stent to an occlusive thrombus. Additionally, endothelial loss at the site of the stent has been implicated in the development of neointimal hyperplasia at the stent situs. Accordingly, rapid re-endothelialization of the arterial wall with concomitant endothelialization of the body fluid or blood contacting surfaces of the implanted device is considered critical for maintaining vasculature patency and preventing low-flow thrombosis. To prevent restenosis and thrombosis in the area where angioplasty has been performed, anti-thrombosis agents and other biologically active agents can be employed.
[0012] It has been found desirable to deliver bioactive agents to the area where a stent is placed concurrently with stent implantation. Many stents have been designed to delivery bioactive agents to the anatomical region of stent implantation. Some of these stents are biodegradable stents which are impregnated with bioactive agents. Examples of biodegradable impregnated stents are those found in U.S. Pat. Nos. 5,500,013, 5,429,634, and 5,443,458. Other known bioactive agent delivery stents include a stent disclosed in U.S. Pat. No. 5,342,348 in which a bioactive agent is impregnated into filaments which are woven into or laminated onto a stent. U.S. Pat. No. 5,234,456 discloses a hydrophilic stent that may include a bioactive agent adsorbed which can include a biologically active agent disposed within the hydrophilic material of the stent. Other bioactive agent delivery stents disclosed in U.S. Pat. Nos. 5,201,778, 5,282,823, 5,383,927; 5,383,928, 5,423,885, 5,441,515, 5,443,496, 5,449,382, 4,464,450, and European Patent Application No. 0 528 039. Other devices for endoluminal delivery of bioactive agents are disclosed in U.S. Pat. Nos. 3,797,485, 4,203,442, 4,309,776, 4,479,796, 5,002,661, 5,062,829, 5,180,366, 5,295,962, 5,304,121, 5,421,826, and International Application No. WO 94/18906. A directional release bioactive agent stent is disclosed in U.S. Pat. No. 6,071,305 in which a stent is formed of a helical member that has a groove in the abluminal surface of the helical member. A bioactive agent is loaded into the groove prior to endoluminal delivery and the bioactive agent is therefore in direct apposition to the tissue that the bioactive agent treats. Finally, International Application No. WO 00/18327 discloses a drug delivery stent in which a tubular conduit is wound into a helical stent. The tubular conduit has either a single continuous lumen or dual continuous lumens that extend the entire length of the conduit. The tubular conduit has regions or segments thereof that has pores to permit drug “seepage” from the conduit. One end of the tubular conduit is in fluid flow communication with a fluid delivery catheter, which introduces a fluid, such as drug into the continuous lumen and through the pores.
[0013] Where bioabsorbable or non-bioabsorbable polymer-based or polymer-coated stents have been used, the polymers may cause an immune inflammatory response once the drug is eluted out of the polymer. Where a polymer is employed as the bioactive agent carrier, it is, therefore, desirable to either isolate or limit exposure of the polymer to body tissues in order to reduce or limit the possibility of immune inflammatory response after the bioactive agent has eluted. By disposing the polymer only in the grooves leaving the remaining device surface uncovered, the contact or surface are for interaction between tissue and polymer is limited.
SUMMARY OF THE INVENTION
[0014] As used herein the term “bioactive agent” is intended to include one or more pharmacologically active compounds which may be in combination with pharmaceutically acceptable carriers and, optionally, additional ingredients such as antioxidants, stabilizing agents, permeation enhancers, and the like. Examples of bioactive agents which may be used in the present invention include but are not limited to antiviral drugs, antibiotic drugs, steroids, fibronectin, anti-clotting drugs, anti-platelet function drugs, drugs which prevent smooth muscle cell growth on inner surface wall of vessel, heparin, heparin fragments, aspirin, coumadin, tissue plasminogen activator (TPA), urokinase, hirudin, streptokinase, antiproliferatives, e.g., methotrexate, cisplatin, fluorouracil, Adriamycin, antioxidants, e.g., ascorbic acid, beta carotene, vitamin E, antimetabolites, thromboxane inhibitors, non-steroidal and steroidal anti-inflammatory drugs, immunosuppresents, such as rapomycin, beta and calcium channel blockers, genetic materials including DNA and RNA fragments, complete expression genes, antibodies, lymphokines, growth factors, e.g., vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF)), prostaglandins, leukotrienes, laminin, elastin, collagen, nitric oxide (NO) and integrins.
[0015] The use of the term “groove” is intended to be construed as an elongate channel, recess or depression, having a length, a width and a depth, the length being greater than the width and the depth being less than a distance between the first surface and second surface of the medical device. The groove may have a wide variety of transverse cross-sectional shapes as described hereinafter, and may have a wide variety of elongate shapes, including linear, curvilinear, meandering, zigzag, sinusoidal, or the like relative to the surface in which the groove resides. The groove may also have constant or variable widths and depths along its length. Provided, however, that at no point along the groove's length may the depth of the groove be greater than the distance between the first surface and second surface of the medical device, that is, a groove is not a slot, even where the slot may be bounded by or in close proximity with an adjacent layer of material, such as in a coiling tubular sheet stent. In the instance of medical device consisting of a coiled sheet of material having successive adjacent layers of the sheet material, the grooves will have a depth less than the thickness of the single sheet before it is coiled and not pass through or form slots passing through any single layer of a coiled medical device.
[0016] The inventive structural material has a three dimensional conformation having a geometry and construction in there is at least one groove in a surface of the structural material and a vehicle or carrier, such as a polymer, for holding or adsorbing the bioactive agent and permitting it to elute from the vehicle or carrier once implanted into the body. The bioactive agent vehicle is disposed only in the at least one groove and does not otherwise cover the surface of the structural material. The three dimensional conformation of the structural material may assume a cylindrical, tubular, planar, spherical, curvilinear or other general shape which is desired and suited for a particular implant application. For example, in accordance with the present invention there is provided an endoluminal stent that is made of a plurality of structural members that define a generally tubular shape for the endoluminal stent. At least some of the plurality of structural members are comprised of the inventive structural material and have at least one groove on at least an inner surface of the stent. Alternate types of implantable devices contemplated by the present invention include, without limitation, stent-grafts, grafts, heart valves, venous valves, filters, occlusion devices, catheters, osteal implants, implantable contraceptives, implantable anti-tumor pellets or rods, or other implantable medical devices.
[0017] In accordance with one embodiment of the present invention, there is provided an endoluminal stent for delivery of bioactive agents. The stent may have plural structural elements or may be made of a single structural element formed into a generally tubular, diametrically expansible stent. At least one groove is provided in at least one of the luminal or inner surface or the abluminal or outer surface of the stent that retains the bioactive agents and permits elution of the bioactive agent therefrom. The at least one groove may be linear, curved, serpentine, zigzag or other configuration in the surface of the stent such that when implanted, at least a portion of the at least one groove is oriented generally parallel to an axis of blood flow within a blood vessel to promote endothelial cell migration and proliferation along the axis of the at least one groove.
[0018] In accordance with another embodiment of the present invention, there is provided a metal thin film, coiling stent, formed of a planar sheet of metal thin film which is coiled into a tubular structure having successive windings of the planar sheet of metal thin film. At least one surface of the planar sheet of metal thin film has at least one groove in the surface such that upon coiling, the at least one groove resides, in full or at least in part, on either the ultimate outer or abluminal surface or the ultimate inner or luminal surface of the coiled stent.
[0019] In accordance with still another embodiment of the present invention there is provided a bioabsorbable polymer formed in a solid or tubular cylindrical shape and having a bioactive agent associated therewith and elutable therefrom. At least one of a plurality of grooves are formed on at least an outer surface of the polymeric cylinder. The cylinder is implantable sub-dermally and the grooves serve to promote endothelial cell growth onto and across the surface Other than described herein, the present invention does not depend upon the particular geometry, material, material properties or configuration of the stent.
[0020] In accordance with the invention, the foregoing advantage has been achieved through the present methods and apparatus for manufacturing an endoluminal stent with at least one groove disposed in the inner surface of the stent.
[0021] In one embodiment of the present invention, there is provided a method of manufacturing a endoluminal stent by first forming a stent having an inner surface and an outer surface; and then forming at least one groove in the inner surface of the stent by etching the inner surface with a mechanical process.
[0022] Various mechanical etching processes can be used. In one preferred embodiment, a mandrel is placed inside the stent, and then a mechanical force is provided to impart at least one groove formed on the outer surface of the mandrel to the inner surface of the stent. Such mechanical force may be provided by one or more calendaring rollers rotating against the outer surface of the stent, or by one or more stamping devices disposed about the outer surface of the stent. The mandrel may have an outer diameter equal to the inner diameter of the stent when the stent is expanded.
[0023] In another preferred embodiment, the mechanical etching process may comprise the steps of placing an impression roller inside the stent, and rotating the impression roller within the stent to impart at least one groove formed on the exterior of the impression roller into the inner surface of the stent.
[0024] In still another preferred embodiment, the mechanical etching process may comprise the steps of disposing the stent upon an expanding mandrel in the unexpanded configuration of the mandrel, and then expanding the mandrel outwardly to impart at least one groove on the outer surface of the mandrel to the inner surface of the stent. Particularly, the expanding mandrel may be formed of a plurality of mating and tapered segments having at least one groove on the outer surface.
[0025] In another preferred embodiment, the mechanical etching process may comprise the step of moving a tapered mandrel into and along the inner surface of the stent. During the movement, the tapered mandrel provides a cutting force, which cuts at least one groove onto the inner surface of the stent. Particularly, the stent is in an expanded configuration, and the tapered mandrel either has a plurality of cutting teeth on its outer surface, or has an outer surface with a metal cutting profile. More particularly, the cutting teeth may be abrasive particles including diamond chips and tungsten carbide chips.
[0026] In another embodiment of the present invention, there is provided a method of manufacturing a metallic intravascular stent by first forming a stent having an inner surface and an outer surface; and then forming at least one groove on the inner surface of the stent by etching the inner surface with a chemical process. Preferably, the chemical process may comprise the steps of coating the inner surface of the stent with a photosensitive material; inserting a mask into the stent; irradiating the inner surface of the stent by a light source; removing the mask from the stent; and etching light exposed areas to produce at least one groove In the inner surface of the stent. The mask may be disposed upon a deflated balloon before its insertion, and the balloon becomes expanded after the insertion. The light source may be a coaxial light source with multiple beams of light in a single plane, and may be displaced along the longitudinal axis of the stent. During the etching process, either the light source may be driven by a stepper motor for rotational movements, or the mask maybe driven for rotational movements with the light source fixed.
[0027] In still another embodiment of the present invention, there is provided a method of manufacturing a metallic intravascular stent by first forming a stent having an inner surface and an outer surface; and then forming at least one groove on the inner surface of the stent by etching the inner surface with a laser.
[0028] In yet another embodiment of the present invention, there is provided a method of manufacturing a metallic intravascular stent by first forming a stent having an inner surface and an outer surface; and then forming at least one groove in the inner surface of the stent by etching the inner surface with an electric discharge machining process. The electric discharge machining process may include the steps of inserting an electric discharge machining electrode into the stent; rotating the electrode within the stent; and providing current to the electrode to cut at least one groove into the inner surface of the stent.
[0029] It has been found that by providing at least one groove on the inner surface of an endoluminal stent, the rate of endothelial cell attachment onto the stent and the rate of migration of endothelial cells along the grooves and the inner surface of the stent is also increased. This leads to a significantly more rapid development of a healthy endothelium at the site of stent placement.
[0030] In still another embodiment of the present invention, there is provided a stent having at least one groove on the inner surface of the stent and a drug-eluting polymer is disposed within the groove, but not otherwise on the inner surface of the stent. This configuration will allow the benefits of the more rapid development of a healthy endothelium than that associated with stents not having the groove, as well as the benefits from the presence of bioactive agents or drugs that can act to suppress cellular
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a partial cross sectional perspective view of a portion of a intravascular stent embedded within an arterial wall of a patient;
[0032] FIG. 2 is an exploded view of the outlined portion of FIG. 1 denoted as FIG. 2 ;
[0033] FIG. 3 is a partial cross-sectional, perspective view corresponding to FIG. 1 after the passage of time;
[0034] FIG. 4 is an exploded view of the outlined portion of FIG. 3 denoted as FIG. 4 ;
[0035] FIG. 5 is a partial cross-sectional view of the stent and artery of FIGS. 1 and 3 after a further passage of time;
[0036] FIG. 6 is an exploded view of the outlined portion of FIG. 5 denoted as FIG. 6 ;
[0037] FIG. 7 is a partial cross-sectional view of the stent and artery of FIG. 5 , taken along lines 7 - 7 of FIG. 5 , and illustrates rapid endothelialization resulting in a thin neointimal layer covering the stent;
[0038] FIG. 8 is a plan view of an interior portion of an unexpanded intravascular stent in accordance with the present invention;
[0039] FIGS. 9-16 are various embodiments of an exploded view of a groove taken along line 9 - 9 of FIG. 8 , illustrating various cross-sectional configurations and characteristics of various embodiments of grooves in accordance with the present invention;
[0040] FIG. 17 is an exploded perspective view of a calendaring apparatus for manufacturing stents in accordance with the present invention;
[0041] FIG. 18 is a partial cross-sectional view of a stamping apparatus for manufacturing stents in accordance with the present invention, looking down the longitudal axis of a mandrel;
[0042] FIG. 19 is an exploded perspective view of an apparatus utilizing an impression roller to manufacturer stents in accordance with the present invention;
[0043] FIG. 20 is an exploded perspective view of an expanding mandrel apparatus for manufacturing stents in accordance with the present invention;
[0044] FIG. 21 is a partial cross-sectional view of the mandrel of FIG. 20 , taken along lines 21 - 21 of FIG. 20 ;
[0045] FIG. 22 is an exploded perspective view of an apparatus utilizing a tapered mandrel to manufacture stents in accordance with the present invention;
[0046] FIG. 23 is an exploded perspective view of an apparatus utilizing a chemical removal method to manufacture stents in accordance with the present invention;
[0047] FIG. 23A is a partial cross-sectional exploded view of a portion of FIG. 23 ;
[0048] FIG. 23B is a partial cross-sectional exploded view of a portion of FIG. 23 ;
[0049] FIG. 24A is an exploded perspective view of an apparatus utilizing a rotating coaxial light source to inscribe microgrooves inside an intact tubular stent in accordance with the present invention;
[0050] FIG. 24B is an exploded perspective view of an apparatus utilizing a rotating mask and fixed light source to inscribe microgrooves inside an intact tubular stent in accordance with the present invention; and
[0051] FIG. 25 is an exploded perspective view of an electric discharge machining apparatus for manufacturing stents in accordance with the present invention.
[0052] FIGS. 26-33 are various embodiments of an exploded view of a groove taken along line 9 - 9 of FIG. 8 , illustrating various cross-sectional configurations and characteristics of various embodiments of grooves having a drug eluting polymer disposed within the groove in accordance with the present invention
[0053] While the invention will be described in connection with the preferred embodiment, it will be understood that it is not intended to limit the invention of that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
[0054] With reference to FIGS. 1 and 2 , an intravascular stent 200 is illustrated being disposed within an artery 290 in engagement with arterial wall 210 . For illustrative purposes only, intravascular stent 200 , shown in FIGS. 1-6 is a Palmaz.™. balloon-expandable stent, as is known in the art, stent 200 having an inner surface 201 and an outer surface 202 . FIGS. 1 and 2 illustrate stent 200 shortly after it has been placed within artery 290 , and after stent 200 has been embedded into arterial wall 210 , as is known in the art. FIGS. 1 and 2 illustrate what may be generally characterized as correct placement of an intravascular stent. Stent 200 preferably includes a plurality of metal members, or struts, 203 , which may be manufactured of stainless steel, or other metal materials, as is known in the art. As illustrated in FIGS. 1 and 2 , correct placement of stent 200 results in tissue mounds 211 protruding between the struts 203 , after struts 203 have been embedded in the arterial wall 210 . Struts 203 also form troughs, or linear depressions, 204 in arterial wall 210 . Dependent upon the degree of blockage of artery 290 , and the type and amount of instrumentation utilized prior to placement of stent 200 , the mounds of tissue 211 may retain endothelial cells (not shown).
[0055] With reference to FIGS. 3 and 4 , after the passage of time, a thin layer of thrombus 215 rapidly fills the depressions 204 , and covers the inner surfaces 201 of stent 200 . As seen in FIG. 4 , the edges 216 of thrombus 215 feather toward the tissue mounds 211 protruding between the struts 203 . The endothelial cells which were retained on tissue mounds 211 can provide for reendothelialization of arterial wall 210 .
[0056] With reference to FIGS. 5 and 6 , endothelial regeneration of artery wall 210 proceeds in a multicentric fashion, as illustrated by arrows 217 , with the endothelial cells migrating to, and over, the struts 203 of stent 200 covered by thrombus 215 . Assuming that the stent 200 has been properly implanted, or placed, as illustrated in FIGS. 1 and 2 , the satisfactory, rapid endothelialization results in a thin tissue layer 218 , as shown in FIG. 7 . As is known in the art, to attain proper placement, or embedding, of stent 200 , stent 200 must be slightly overexpanded. In the case of stent 200 , which is a balloon-expandable stent, the balloon diameter chosen for the final expansion of stent 200 must be 10% to 15% larger than the matched diameter of the artery, or vessel, adjacent the site of implantation. As shown in FIG. 7 , the diameter Di of the lumen 219 of artery 290 is satisfactory. If the reendothelialization of artery wall 210 is impaired by underexpansion of the stent or by excessive denudation of the arterial wall prior to, or during, stent placement, slower reendothelialization occurs. This results in increased thrombus deposition, proliferation of muscle cells, and a decreased luminal diameter Di, due to the formation of a thicker neointimal layer.
[0057] With reference to FIG. 8 , an intravascular stent 300 in accordance with the present invention is illustrated. For illustrative purposes only, the structure of intravascular stent 300 is illustrated as being a PALMAZ balloon-expandable stent, as is known in the art, illustrated in its initial, unexpanded configuration. It should be understood that the improvement of the present invention is believed to be suitable for use with any intravascular stent having any construction or made of any material as will be hereinafter described. Similarly, the improvement of the present invention in methods for manufacturing intravascular stents, is also believed to be applicable to the manufacturing of any type of intravascular stent as will also be hereinafter described.
[0058] As illustrated in FIG. 8 , intravascular stent, or stent, 300 has an inner surface 301 , and an outer surface 302 , outer surface 302 normally being embedded into arterial wall 210 in an abutting relationship. In accordance with the present invention, the inner surface 301 of stent 300 is provided with at least one groove 400 . If desired, as will be hereinafter described in greater detail, a plurality of grooves 400 could be provided on, or in, inner surface 301 of stent 300 . The at least one groove 400 , or grooves, of the present invention may be provided in, or on, the inner surface 301 of stent 300 in any suitable manner, such as by: abrading the inner surface 301 of stent 300 to provide the at least one groove 400 ; a chemical or mechanical etching process; use of a laser or laser etching process; use of a diamond-tipped tool; use of any suitable abrasive material; or use of any tool or process, which can provide the desired groove, or grooves, 400 in, or on, the inner surface 301 of stent 300 , as will be hereinafter described in greater detail.
[0059] As shown in FIG. 8 , the at least one groove, or grooves, 400 may be disposed with its longitudinal axis 410 being disposed substantially parallel with the longitudinal axis 305 of stent 300 . Alternatively, the longitudinal axis 410 of the at least one groove 400 may be disposed substantially perpendicular to the longitudinal axis 305 of stent 300 , as illustrated by groove 400 ″″; or the longitudinal axis 410 of the groove may be disposed at an obtuse, or acute, angle with respect to the longitudinal axis 305 of stent 300 , as illustrated by groove 400 ′. The angle that groove 400 ′ makes with respect to longitudinal axis 305 is either an acute or an obtuse angle dependent upon from which direction the angle is measured with respect to the longitudinal axis 305 of stent 300 . For example, if the angle between the longitudinal axis of groove 400 ′ and longitudinal axis 305 is measured as indicated by arrows A, the angle is an acute angle. If the angle is measured, as at arrows B, the angle is an obtuse angle.
[0060] Still with reference to FIG. 8 , a plurality of grooves 400 may be provided on the inner surface 301 of stent 300 , two grooves 400 being shown for illustrative purposes only. Instead of a plurality of individual grooves, such as grooves 400 , a single groove 400 ″ could be provided in a serpentine fashion, so as to cover as much of the inner surface 301 of stent 300 as desired. Similarly, the grooves could be provided in a cross-hatched manner, or pattern, as shown by grooves 400 ″′. Grooves 400 , 400 ′, 400 ″, 400 ″′, and 400 ″″ could be provided alone or in combination with each other, as desired, to provide whatever pattern of grooves is desired, including a symmetrical, or an asymmetrical, pattern of grooves. It should be noted that the angular disposition and location of the various grooves 400 - 400 ″″ will vary and be altered upon the expansion of stent 300 within artery 201 ( FIG. 1 ), stent 300 being illustrated in its unexpanded configuration in FIG. 8 . Similarly, if stent 300 were a stent made of wire or lengths of wire, the disposition and angular orientation of the grooves formed on such wire, or wire members, would similarly be altered upon the expansion and implantation of such stent. It should be further noted, as previously discussed, that the groove, or grooves, may be provided in, or on, the inner surface of any intravascular stent, so as to increase the rate of migration of endothelial cells on, and over, the inner surface of the intravascular stent.
[0061] With reference to FIGS. 9-16 , various embodiments of groove 400 will be described in greater detail. In general, as seen in FIG. 9 , groove 400 has a width W, a depth D, and a length L ( FIG. 8 ). The width W and depth D may be the same, and not vary, along the length L of the groove 400 . Alternatively, the width W of the groove may vary along the length L of the groove 400 . Alternatively, the depth D of the groove may vary along the length L of the at least one groove. Alternatively, both the width W and the depth D of the groove 400 may vary along the length of the at least one groove. Similarly, as with the location and angular disposition of groove, or grooves, 400 as described in connection with FIG. 8 , the width W, depth D, and length L of the groove, or grooves, 400 can vary as desired, and different types and patterns of grooves 400 could be disposed on the inner surface 301 of stent 300 .
[0062] As shown in FIGS. 9-16 , groove 400 may have a variety of different cross-sectional configurations. As desired, the cross-sectional configuration of the groove, or grooves, 400 may vary along the length L of the groove; or the cross-sectional configuration of the groove may not vary along the length of the at least one groove 400 . Similarly, combinations of such cross-sectional configurations for the grooves could be utilized. The cross-sectional configuration of the groove, or grooves, 400 may be substantially symmetrical about the longitudinal axis 410 of groove 400 as illustrated in FIGS. 8 and 9 ; or the cross-sectional configuration of the at least one groove may be substantially asymmetrical about the longitudinal axis 410 of the least one groove, as illustrated in FIGS. 14 and 16 . The cross-sectional configurations of groove 400 can assume a variety of shapes, some of which are illustrated in FIGS. 9-16 , and include those cross-sectional configurations which are substantially: square shaped ( FIG. 9 ); U shaped ( FIG. 10 ); triangular, or V shaped ( FIG. 1 ); rectangular shaped ( FIG. 12 ); and triangular, or keyway shaped ( FIG. 13 ). The wall surface 303 of each groove 400 may be substantially smooth, such as illustrated in FIGS. 9-13 , or wall surface 303 may be jagged, or roughened, as illustrated in FIGS. 14 and 16 . As illustrated in FIG. 15 , wall surface 303 could also be provided with at least one protrusion 304 and at least one indentation 305 if desired, and additional protrusions and indentations 304 , 305 could be provided as desired.
[0063] The depth D of groove, or grooves, 400 may fall within a range of approximately one-half to approximately ten microns. The width W of groove, or grooves, 400 , may fall within a range of approximately two to approximately forty microns. Of course, the width W and depth D could be varied from the foregoing ranges, provided the rate of migration of endothelial cells onto stent 300 is not impaired. The length L of groove 400 may extend the entire length of stent 300 , such as groove 400 of FIG. 8 ; or the length L′ of a groove may be less than the entire length of stent 300 , such as groove 400 ″″ in FIG. 8 . The groove, or grooves, of the present invention may be continuous, or discontinuous, along inner surface 301 of stent 300 .
[0064] The portion of the inner surface 301 of stent 300 which has not been provided with a groove, or grooves, 400 in accordance with the present invention, may have any suitable, or desired, surface finish, such as an electropolished surface, as is known in the art, or may be provided with whatever surface finish or coating is desired. It is believed that when at least one groove in accordance with the present invention is disposed, or provided, on, or in, the inner surface 301 of an intravascular stent 300 , after the implantation of stent 300 , the rate of migration of endothelial cells upon the inner surface 301 of stent 300 will be increased over that rate of migration which would be obtained if the inner surface 301 were not provided with at least one groove in accordance with the present invention.
[0065] To manufacture intravascular stents with at least one groove disposed in the inner surface of the stent, the current best technology for inscribing microgrooves on metals seems to be photoetching. The present invention provides improved methods of inscribing the grooved pattern inside an intact tubular stent.
[0066] With reference to FIG. 17 , a calendaring apparatus 450 is illustrated forming at least one groove 400 (not shown) on, or in, the inner surface 301 of stent blank 300 . Calendaring apparatus 450 includes at least one calendaring roller 451 and an inner mandrel 452 . Calendaring roller 451 is provided with a bearing shaft 453 and a pinion gear 454 , which is driven by a gear drive 455 and gear drive apparatus 456 . Bearing shaft 453 is received in a bearing block 457 , which has a groove 458 for receipt of bearing shaft 453 . Bearing block 457 also includes a bottom plate 459 and bearing block 457 is movable therein, in the direction shown by arrows 460 , as by slidably mating with slots 461 formed in bottom plate 459 . Bearing block 457 is further provided with an opening, or bearing journal, 465 for rotatably receiving mounting hub 466 disposed upon the end of mandrel 452 . Calendaring roller is rotated in the direction shown by arrow 467 and bears against the outer surface 302 of stent blank 300 , with a force sufficient to impart the groove pattern 468 formed on the outer surface of mandrel 452 to the inner surface 301 of stent blank 300 . Mandrel 452 will have a raised groove pattern 468 on the outer surface of mandrel 452 , corresponding to the desired groove, or grooves, 400 to be formed on, or in, the inner surface 301 of stent 300 . The raised groove pattern 468 of mandrel 452 must be hardened sufficiently to enable the formation of many stents 300 without dulling the groove pattern 468 of mandrel 452 . Mandrel 452 may have a working length corresponding to the length of the stent 300 and an overall length longer than its working length, to permit the receipt of mandrel mounting hub 466 within bearing block 457 and mounting hub 466 within gear drive apparatus 456 .
[0067] Still with reference to FIG. 17 , the outer diameter of mandrel 452 is preferably equal to the inner diameter of the stent 300 in its collapsed state. The groove pattern 468 may correspond to the desired groove pattern of groove, or grooves, 400 to be formed on the inner surface 301 of stent 300 after stent 300 has been fully expanded. If the desired groove pattern upon expansion of stent 300 is to have the groove, or grooves 400 become parallel to each other upon expansion of the stent 300 , along the longitudal axis of the expanded stent 300 , groove pattern 468 , or the pre-expanded groove pattern, must have an orientation to obtain the desired post expansion groove pattern, after radial expansion of stent 300 . Stent 300 may be pre-expanded slightly to facilitate its placement on the mandrel 452 in order to prevent scratching of the stent 300 . Mandrel 452 may include an orientation mechanism, or pin 469 which mates with a corresponding notch 469 ′ on stent blank 300 , in order to insure proper orientation of stent blank 300 with respect to mandrel 452 . Stent 300 may be crimped circumferentially around mandrel 452 after it has been properly oriented. The force to impart the desired groove pattern 468 upon, or in, the inner surface 301 of stent 300 is provided by calendaring roller 451 .
[0068] With reference to FIG. 18 , an alternative structure is provided to impart the desired groove pattern in, or upon, the inner surface 301 of stent blank 300 . In lieu of calendaring roller 451 , a punch press, or stamping apparatus, 470 may be utilized to force the inner surface 301 of stent 300 upon the groove pattern 468 of mandrel 452 . Stamping apparatus 470 may include a hydraulic cylinder 471 and hydraulic piston 472 , attached to a stamping segment 473 . The inner surface 474 of stamping segment 473 has a radius of curvature which matches the outer radius of curvature 475 of stent 300 , when it is disposed upon mandrel 452 . If desired, a plurality of stamping devices 470 ′ may be disposed about the outer surface 302 of stent 300 , or alternatively a single stamping device 470 may be utilized, and stent 300 and mandrel 452 may be rotated to orient the stent 300 beneath the stamping segment 473 .
[0069] With reference to FIG. 19 , the desired grooves 400 may be formed on the inner surface 301 of stent blank 300 by an impression roller 480 which serves as the inner mandrel. Impression roller 480 is supported at its ends by roller bearing block 481 , similar in construction to previously described bearing block 457 . Similarly, a gear drive, or drive gear mechanism, 482 may be provided, which is also similar in construction to gear drive 455 . Impression roller 480 has a bearing shaft 483 at one end of impression roller 480 , bearing shaft 483 being received by an opening, or journal bearing, 484 in bearing block 481 . The other end of impression roller 480 may have a pinion gear 485 which is received within rotating ring gear 486 in gear drive mechanism 482 . A backup housing, such as a two-part backup housing 487 , 487 ′ may be provided for fixedly securing stent blank 300 while impression roller 480 is rotated within stent blank 300 to impart groove pattern 468 formed on the exterior of impression roller 480 to the inner surface 301 of stent blank 300 .
[0070] With reference to FIGS. 20 and 21 , an expanding mandrel apparatus 500 for forming the desired at least one groove 400 on, or in, the inner surface 301 of stent blank 300 is illustrated. Expanding mandrel 501 is preferably formed of a plurality of mating and tapered segments 502 having the desired groove pattern 468 formed on the outer surface 503 of each segment 502 . Stent blank 300 is disposed upon expanding mandrel 501 in the unexpanded configuration of expanding mandrel 501 , stent blank 300 being oriented with respect to mandrel 501 , as by the previously described notch 469 ′ and pin 469 . A backup housing 487 and 487 ′, as previously described in connection with FIG. 19 , may be utilized to retain stent blank 300 while expanding mandrel 501 is expanded outwardly to impart the desired groove pattern 468 upon, or in, the inner surface 301 of stent blank 300 . In this regard, expanding mandrel 501 is provided with a tapered interior piston 505 , which upon movement in the direction of arrow 506 forces mandrel segments 502 outwardly to assume their desired expanded configuration, which forces groove pattern 468 on mandrel 501 against the inner surface 301 of stent blank 300 . O-rings 507 may be utilized to secure stent 300 upon mandrel 501 .
[0071] With reference to FIG. 22 , a tapered mandrel groove forming apparatus 530 is illustrated. Tapered mandrel 531 is supported by a mandrel support bracket, or other suitable structure, 532 to fixedly secure tapered mandrel 531 as shown in FIG. 22 . The end 533 of tapered mandrel 531 , has a plurality of cutting teeth 534 disposed thereon. The cutting teeth 534 may be abrasive particles, such as diamond chips, or tungsten carbide particles or chips, which are secured to tapered mandrel 531 in any suitable manner, and the cutting teeth 534 form the desired groove, or grooves, 400 on, or in, the inner surface 301 of stent blank 300 . Alternatively, instead of cutting teeth 534 , the outer surface 535 of tapered mandrel 531 could be provided with a surface comparable to that formed on a metal cutting file or rasp, and the file, or rasp, profile would form the desired grooves 400 . A stent holding fixture 537 is provided to support stent blank 300 in any desired manner, and the stent holding fixture 367 may be provided with a piston cylinder mechanism, 368 , 369 to provide relative movement of stent 300 with respect to tapered mandrel 531 . Alternatively, stent 300 can be fixed, and a suitable mechanism can be provided to move tapered mandrel 531 into and along the inner surface 301 of stent 300 . Preferably, stent 300 is in its expanded configuration.
[0072] With reference to FIGS. 23 , 23 A and 23 B, a chemical removal technique and apparatus 600 for forming the desired groove, or grooves, 400 on, or in, the interior surface 301 of stent blank 300 is illustrated. A stent holding fixture 601 is provided, and holding fixture 601 may be similar in construction to that of stent holding fixture 367 of FIG. 22 . Again, stent blank 300 is provided with an orientation notch, or locator slot, 469 ′. A photo mask 602 is formed from a material such as Mylar film. The dimensions of the mask, 602 correspond to the inner surface area of the inner surface 301 of stent 300 . The mask 602 is formed into a cylindrical orientation to form a mask sleeve 603 , which is wrapped onto a deflated balloon 605 , such as a balloon of a conventional balloon angioplasty catheter. A conventional photoresist material is spin coated onto the inner surface 301 of stent blank 300 . The mask sleeve 603 , disposed upon balloon 605 is inserted into stent 300 , and balloon 605 is expanded to force the mask sleeve 603 into an abutting relationship with the photoresist coated inner surface 301 of stent 300 . Balloon 605 may be provided with an orientation pin 606 which corresponds with an orientation notch 607 on mask sleeve 603 , which in turn is also aligned with locator slot 469 ′ on stent blank 300 . The expansion of balloon 605 is sufficient to sandwich mask sleeve 603 into abutting contact with the photoresist coated inner surface 301 of stent 300 ; however, the balloon 605 is not inflated enough to squeeze the photoresist material off the stent 300 . The interior surface 301 of stent 300 is then irradiated through the inside of the balloon 605 through the balloon wall, as by a suitable light source 610 . Balloon 605 is then deflated and mask sleeve 603 is removed from the interior of stent 300 . The non-polymerized photoresist material is rinsed off and the polymerized resist material is hard baked upon the interior of stent 300 . The groove, or grooves 400 are then chemically etched into the non-protected metal surface on the interior surface 301 of stent 300 . The baked photoresist material is then removed by either conventional chemical or mechanical techniques.
[0073] Alternatively, instead of using a Mylar sheet as a mask 602 to form mask sleeve 603 , mask 602 may be formed directly upon the outer surface of balloon 605 , as shown in FIG. 23A . The production of mask 602 directly upon the balloon outer surface can be accomplished by physically adhering the mask 602 onto the outer surface of balloon 605 , or by forming the mask 602 onto the surface of balloon 605 by deposition of the desired groove pattern 468 by deposition of UV absorbing material by thin film methods. In the case of utilizing mask sleeve 603 as shown in FIG. 23B , the balloon material must be compliant enough so as to prevent creases from the balloon wall which may shadow the resulting mask 602 . In the case of mask 602 being formed on balloon 605 as shown in FIG. 23A , a non-compliant balloon 605 should be used, so as not to distort the resulting image by the stretching of the compliant balloon wall. If on the other hand, the mask 602 is physically adhered to the outer wall of balloon 605 , a compliant balloon 605 may be used provided the mask 602 is adhered to the balloon 605 when the balloon 605 is in its fully expanded diameter.
[0074] With reference to FIGS. 24A and 24B , a method is shown for creating grooves inside an intact tubular stent 300 , which involves casting patterned light inside a stent 300 previously coated with photosensitive material as discussed, for example, in connection with FIG. 23 (PSM). The light exposed areas are subjected to chemical etching to produce the grooved pattern. This method involves using a coaxial light source 800 with multiple small beams 801 of light in a single plane. The light source 800 could be displaced along the longitudinal axis of the tube, or stent 300 , at a rate consistent with adequate exposure of the photosensitive material. Computer driven stepper motors could be utilized to drive the light source in the x and y planes, which would allow for interlacing grooves (see FIG. 24A ). One pass could create 1 mm spacing, while the next pass creates 500 μm, and so on.
[0075] Rotational movements could introduce variability in the groove direction for zig-zag, spiral or undulating patterns. Alternatively, the light source 800 could be fixed as shown in FIG. 24 B, and the beams would be as narrow and long as the grooves needed on the inner surface of the mask 602 . Stepping of the mask 602 would allow narrow spacing of the grooves.
[0076] With reference to FIG. 25 , an EDM process and apparatus 700 provide the desired groove, or grooves, 400 upon the interior 301 of stent 300 . A non-conductive stent alignment and holding fixture 701 , 701 ′, similar in construction to backup housings 487 , 487 ′, previously described, are provided for holding stent like blank 300 . A bearing block assembly 702 , similar to bearing block assembly 481 of FIG. 19 , is provided along with an indexing and current transfer disk 703 provided within a drive gear mechanism 704 , which is similar in construction to drive gear mechanisms 482 and 455 , previously described in connection with FIGS. 19 and 17 . An electric discharge machining (“EDM”) electrode 710 having bearing shafts 711 , 712 , disposed at its ends, for cooperation with bearing block assembly 702 and disk 703 , respectively, is rotated within stent blank 300 . Current is provided to the raised surfaces, or groove pattern, 468 , of electrode 710 to cut the desired groove, or grooves 400 into the inner surface 301 of stent 300 .
[0077] Finally, turning to FIGS. 26-33 there is illustrate the another embodiment of the present invention which includes a polymer-filled groove 800 . Like the foregoing described embodiments of the at least one groove 400 described with reference to FIGS. 9-16 , the polymer-filled groove 800 may have a variety of different cross-sectional configurations. As desired, the cross-sectional configuration of the groove, or grooves, 800 may vary along the length L of the groove; or the cross-sectional configuration of the groove may not vary along the length of the at least one groove 800 . Similarly, combinations of such cross-sectional configurations for the grooves could be utilized. The cross-sectional configuration of the groove, or grooves, 800 may be substantially symmetrical about the longitudinal axis of groove 800 ; or the cross-sectional configuration of the at least one groove may be substantially asymmetrical about the longitudinal axis of the least one groove. The cross-sectional configurations of groove 400 can assume a variety of shapes, some of which are illustrated in FIGS. 26-33 , and include those cross-sectional configurations which are substantially: square shaped ( FIG. 26 ); U shaped ( FIG. 27 ); triangular, or V shaped ( FIG. 28 ); rectangular shaped ( FIG. 29 ); and truncated triangular, or keyway shaped ( FIG. 30 ). The wall surface 303 of each groove 800 may be substantially smooth, such as illustrated in FIGS. 26-30 , or wall surface 303 may be jagged, or roughened, as illustrated in FIGS. 31 and 33 . As illustrated in FIG. 32 , wall surface 303 could also be provided with at least one protrusion 304 and at least one indentation 305 if desired, and additional protrusions and indentations 304 , 305 could be provided as desired.
[0078] The depth D of groove, or grooves, 800 may fall within a range of approximately one-half to approximately ten microns. The width W of groove, or grooves, 800 , may fall within a range of approximately two to approximately forty microns. Of course, the width W and depth D could be varied from the foregoing ranges, provided the rate of migration of endothelial cells onto stent 300 is not impaired. The length L of groove 800 may extend the entire length of stent 300 , such as groove 400 of FIG. 8 ; or the length L′ of a groove 800 may be less than the entire length of stent 300 , such as groove 400 ″″ in FIG. 8 . The groove, or grooves, of the present invention may be continuous, or discontinuous, along inner surface 301 of stent 300 .
[0079] A biocompatible polymer 810 is disposed within at least a portion of groove 800 , and more preferably at least a substantial portion of groove 800 . Biocompatible polymer 810 is of the type capable of eluting bioactive agents. Specific bioactive agent eluting polymers are well known in the art and are hereby incorporated by reference.
[0080] The biocompatible polymer 810 is present only in the groove 800 and not otherwise on either the inner surface 301 or the outer surface 302 of the stent 300 . As discussed above, the portion of the inner surface 301 or outer surface 302 of stent 300 which has not been provided with a groove, or grooves, 800 , and therefore does not have polymer 810 thereupon, may have any suitable, or desired, surface finish, such as an electropolished surface, as is known in the art, or may be provided with whatever surface finish or coating is desired. It has been found that when at least one groove in accordance with the present invention is disposed, or provided, on, or in, the inner surface 301 of an intravascular stent 300 , after the implantation of stent 300 , the rate of attachment, migration and proliferation of endothelial cells upon the inner surface 301 of stent 300 is increased over that rate of attachment, migration and proliferation observed in stents that do not have the at least one groove in accordance with the present invention.
[0081] Table 1, below, summarizes the migration distance of endothelial cells onto metal, polymer and hybrid metal-polymer coupon surfaces both with and without grooves in accordance with the present invention. The tests reflected in Table 1 were conducted by preparing metal coupon samples which were 1 cm square of either All coupon samples are 1 cm square 316L Stainless steel or L605 Cobalt-Chrome with exposed metal surfaces electropolished and passivated. Coupon thickness was between about 0.020″-0.025″. Parylene C was coated onto the coupons by chemical vapor deposition to a thickness between 2-3 microns. Groove dimensions were 12 microns in width and 3 microns in depth with 12 micron spacing between adjacent grooves. Three replicates of each sample type were used.
[0082] The metal only coupons were cute using wire electrical discharge machining (EDM), mechanically polished, then electropolished, passivated in acid and then cleaned and packaged. The parylene C coated coupons were cut from a sheet of metal, coated with parylene C and then cleaned and packaged. The Parylene C coated, grooved coupons were cut from a metal sheet, mechanically polished, grooves were formed by laser ablation and then the entire surface, including the groove pattern was coated with Parylene C as noted above, the coated coupon was then cleaned and packaged. The Parylene C coated coupon with an exterior surface having metal grooves was prepared by cutting the coupons from a metal sheet, mechanically polishing, followed by coating with Parylene C as described above, then forming a groove pattern by laser ablation through the Parylene coating and into the metal coupon, then electropolishing to a final groove depth, followed by passivating the exposed metal, neutralizing the passivation, cleaning and packaging the coupons. Finally, the coupons having Parylene filled grooves with an exposed exterior metal surface were prepared by cutting the coupons from a metal sheet, mechanically polishing the coupon, laser ablating the groove pattern into the metal coupon, then coating the coupon with Parylene, mechanically polishing or planarizing the grooved surface to expose the metal land areas between adjacent grooves, ultrasonically cleaning the coupon, electropolishing the exposed metal, passivating the exposed metal, neutralizing the passivating acid, cleaning and packaging the coupon.
[0000]
TABLE 1
Endothelial Cell
Sample
Migration Distance
No.
Material Description
(mm/10 days)
1a
316L Stainless Steel—Electropolished
1.75 ± 0.25
and ungrooved
2a
316L Stainless Steel—Parylene C
0.167 ± 0.14
Coated and ungrooved
3a
316 L Stainless Steel—Grooved and
1.68 ± 0.38
Parylene C Coated
4a
316L Stainless Steel—Parylene C
4.93 ± 0.1
Coated and Grooved through Parylene to
expose metal
5a
316L Stainless Steel—Grooved and
5.0 ± 0.0
Parylene C filling the grooves with
exposed metal lands between grooves
1
CoCr L605—Electropolished and
1.125 ± 0.11
ungrooved
2
CoCr L605—Parylene C Coated and
0.1 ± 0.0
ungrooved
3
CoCr L605—Parylene C Coated and
5.0 ± 0.0
Grooved through Parylene to expose metal
4
CoCr L605—Grooved and Parylene C
3.95 ± 0.16
filling the grooves with exposed metal
lands between grooves
[0083] As will be understood from Table 1, both the Parylene filled metal grooves and the Parylene covered landing regions between exposed metal grooves exhibited significantly greater endothelial cell migration when compared to a bare metal surface, an ungrooved Parylene coated metal surface or a grooved Parylene coated metal surface without metal exposed.
[0084] It is to be understood that the invention is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art. Accordingly, the invention is therefore to be limited only by the scope of the appended claims. | The invention relates to methods and apparatus for manufacturing implantable medical devices, such as intravascular stents, wherein the medical device has a surface treated to promote the migration of endothelial cells onto the surface of the medical device. In particular, the surface of the medical device has at least one groove formed therein, the at least one groove may have a drug-eluting polymer disposed therein or a drug-eluting polymer coating may be provided on the surface of the medical device and grooves formed in the drug eluting polymer coating. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is based upon and claims priority to German Patent Application 199 44 748.9 filed Sep. 17, 1999, which application is herein expressly incorporated by reference.
BACKGROUND OF THE INVENTION
The invention relates to a side strut for a lower steering arm of a tractor. Side struts are used to at least temporarily stabilize lateral pivotable lower steering arms of a tractor. Side struts prevent the lower steering arms from being pivoted. The side struts are designed such that, when an implement is lifted, the implement and the lower steering arms are automatically centered centrally relative to the longitudinal axis of the tractor. Furthermore, the side struts serve to hold the lower steering arms at a predetermined distance from one another in accordance with the category of the to be attached implement. This enables the implement to be coupled automatically from the driver's seat.
DE 197 37 318 A1 discloses an assembly where one lower steering arm of a tractor attaching device is associated with a single-action, double-stage telescopic cylinder. The other lower steering arm is associated with a single-action, single-state hydraulic cylinder in the form of a side strut. The piston rod of the single-stage hydraulic cylinder includes a bore with a freely movable guiding rod. At its free end, the guiding rod or the piston rod of one of the two cylinders includes a thread to receive an attaching element to connect to the lower steering arm. The attaching element can be threaded over a shorter or longer distance. One stage of the double-stage telescopic cylinder serves to compensate for any play and to adapt to a certain category. A tension spring is arranged between the attaching means associated with the piston rod and the outside of the cylinder housing. The tension spring loads the pistons and the guiding rod to enable them to assume their moved-in positions. The tension spring is arranged eccentrically relative to the longitudinal axis of the side strut. In consequence, the spring is unprotected, so that the dimension of spread between the two lower steering arms changes if no implement is attached. In order to couple the implement, the correct dimension of spread has to be re-set. Furthermore, the effect of the spring may be adversely affected by rough operating conditions.
DE-GM 19 749 38 describes side struts that are associated with the lower steering arms of a tractor. Each side strut has a tube with a first attaching means and an adjustable journal. The adjustment is limited by stops. A further attaching means is also provided. If the lower steering arms are connected to one another by a liftlink drawbar, the connection with the lower steering arms can be effected to ensure free lateral movability or that such movability is eliminated. In addition, any play can be compensated for by the play of the thread. A central setting effect from a certain lifted position of the lower steering arm onwards is not possible.
DE 197 44 328 C1 describes a side strut which can be used for the lower steering arms of a tractor. The side strut has a single-action hydraulic cylinder with a piston and a cylinder housing. One end of a piston rod associated with the piston projects from the cylinder housing. The rod carries a first attaching means which is connected to a corresponding attaching means at the rear of the tractor.
The cylinder housing is axially followed by a hollow cylinder. An adjustable rod-shaped setting element is arranged in the hollow cylinder. The setting element is guided in the hollow cylinder by two spaced guiding rings. A pressure spring is arranged between the guiding rings. The spring is loaded into a moved-in position in which the setting element, by means of one end face, is supported against the base of the cylinder housing. The piston and the setting element can be moved out in opposite directions. The end of the setting element projects from the hollow cylinder when the setting element is moved in. The setting element includes a threaded bore which is engaged by a threaded rod. The second attaching means is attached to the threaded rod and is connectable to the associated lower steering arm. The basic axial length resulting from arranging the cylinder housing, the hollow cylinder, and the setting device for the category setting means with the threaded bore and the threaded bar one behind the other is too great for the installation conditions prevailing in modern tractors. Thus, the pivoting path of the lower steering arm is restricted.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a side strut which is as short as possible. Also, a side strut is provided where the position of the piston in the cylinder housing remains unaffected by the spring.
In accordance with the invention, a side strut includes a single-action hydraulic cylinder. The single-action hydraulic cylinder has a cylinder housing, a piston including a hollow cylinder and a base closing one end of the hollow cylinder. The end of the piston with the base enters the cylinder housing. The hollow cylinder is guided out of the cylinder housing. The piston in the cylinder housing is movable along a longitudinal axis. The single-action hydraulic cylinder, further includes a first attaching means. The side strut further includes a setting means. The setting means includes a rod-shaped setting element arranged in the hollow cylinder. The rod-shaped element is co-axially arranged in the hollow cylinder and rotatable around the longitudinal axis. The rod-shaped element is also adjustable relative to the hollow cylinder between a first position, where it is moved into the hollow cylinder, and a second position, where it is moved out of the hollow cylinder. The setting element has a threaded bore arranged and centered on the longitudinal axis. The threaded bore starts from a second end face which projects from the open end of the hollow cylinder. The setting means further includes a spring means arranged in the hollow cylinder around the setting element. The spring means is effective between the piston and the setting element only. The spring means loads the setting element to enable the setting element to assume the moved-in position. The setting element, via a first end face, is in contact with the base face of the base of the piston in the moved-in position. The spring means allow the setting element to be adjusted in a direction which corresponds to the direction in which the piston is moved out of the cylinder housing. The setting means further include an actuating means to enable rotational displacement of the setting element. The setting means further includes a threaded rod connected to the second attaching means. The threaded rod is displacably received in the threaded bore of the setting element.
The telescopic design achieves short lengths between the attaching means. As a result, when use is made of the lower steering arms of a tractor, the lower steering arms include a great lateral freedom of movement. In addition, because the piston and the setting element move in the same direction when they are moved out, a short buckling length is achieved. This is advantageous from a buckling strength viewpoint. It is also advantageous that the spring means is protected. Thus, when the setting element is in the moved-in condition, the spring means hold the setting element by a first end face in contact with the base face of the base of the piston. The thread enables an adjustment to a certain category and to eliminate play when the implement is coupled. The spring only serves to adjust the setting element. It has no influence on the position of the piston in the cylinder.
According to a preferred embodiment, a setting element is guided through two guiding rings in the hollow cylinder. A first guiding ring and a second guiding ring are arranged on the outer face of the setting element. The compact arrangement is further improved by securing the first guiding ring in the hollow cylinder at the end removed from the cylinder housing in the moving-out direction of the setting element. The second guiding ring is secured at the end of the setting element, which faces the base of the piston, in a direction corresponding to the moving-in direction of the setting element. The spring means is arranged between the two guiding rings and between the outer face of the setting element and the inner face of the hollow cylinder. The spring means is in the form of a pressure element. The setting element is rotatably held in the two guiding rings.
By rotating the setting element, the length between the attaching means is changed. To facilitate such rotation, the actuating means are provided by an actuating lever attached to the setting element end which projects from the hollow cylinder. The actuating lever can be secured to the holding means in order to prevent any unintentional adjustment.
The first attaching means is preferably connected to the cylinder housing. A particularly compact design is achieved by arranging the threaded bore in the setting element such that, in the moved-in condition of the setting element, the setting element is at least partially positioned inside the hollow cylinder and thus inside the piston. Extremely short lengths are achieved so that a particularly advantageous short buckling length is also achieved.
From the following detailed description, taken in conjunction with the drawings and subjoined claims, other objects and advantages of the present invention will become apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention is illustrated in the drawings wherein:
FIG. 1 is a diagrammatic plan view of the lower steering arms of a three-point attaching device of a tractor with the side struts associated with the lower steering arms.
FIG. 2 is a longitudinal section view through a side strut.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a diagrammatic plan view of two lower steering arms 1 , 1 ′ attached by suitable attaching means at the fixing points 3 , 3 ′ at the rear of the tractor. The arms 1 , 1 ′ are pivotable around a pivot axis 2 . The two fixing points 3 , 3 ′ are laterally offset from the longitudinal tractor axis 8 by equal amounts. The two lower steering arms 1 , 1 ′ are able to carry out both lateral and lifting movements. The arms pivot around the pivot axis upward and downward, out of and into the drawing plane. This is shown in FIG. 1 from the position shown in continuous lines into the position shown in dashed lines.
Coupling hooks 4 are provided to prevent lateral movements of the two lower steering arms 1 , 1 ′. The coupling hooks 4 receive corresponding coupling means at the implement to pull the implement or to carry the implement in cooperation with an upper steering arm (not illustrated). The upper steering arm is normally centered on the longitudinal tractor axis 8 above the pivot axis 2 . The one end of the two side struts 5 are secured by a first attaching means 6 to a suitable fixing means at the rear of the tractor. The fixing means are centered on the pivot axis 2 . The side struts are laterally offset relative to the fixing points 3 , 3 ′. A second attaching means 7 , at the other ends of the side struts 5 , connects the side struts to a lower steering arm 1 , 1 ′. The attaching means 6 , 7 enable a pivot movement. Furthermore, as can be seen in FIG. 1, the pivot axes of the attaching means 7 are arranged at a radius R relative to the fixing points 3 , 3 ′. Thus, the attaching means 7 carry out a pivot movement with the radius R.
If, with an attached implement, a side movement S occurs at the two lower steering arms 1 , 1 ′, with the two lower steering arms 1 , 1 ′ being displaced from the position shown in continuous lines into the position shown in dashed lines, a length change occurs for the two lower steering arms 1 , 1 ′. Starting from identical distances L 1 and L 2 between the pivot axes of the articulation points 6 , 7 , the dimension L is increased to L 1 ′, whereas the dimension L 2 is shortened to dimension L 2 ′. The changes in length vary with respect to magnitude. If the lower steering arms 1 , 1 ′ pivoted clockwise around the fixing points 3 , 3 ′, the length L 1 would be shortened and the length L 2 would be lengthened. When shortening takes place, care must be taken to ensure that the lower steering arm 1 ′, in its dashed position, does not hit the rear wheels.
Furthermore, the two side struts 5 hold the attached implement centered on the longitudinal tractor axis 8 when the attached implement is in the lifted transport position. The same applies if no implement is attached and if the lower steering arms 1 , 1 ′ are in the transport position. In this condition, the two side struts ensure that the lower steering arms 1 , 1 ′ are held so that they cannot move sideways from the set dimension of spread A from the longitudinal tractor axis 8 outwardly towards the rear wheels. The dimension of spread A between the coupling hooks 4 of the two lower steering arms 1 , 1 ′ can be manually set. Here, a settable telescopic setting means is integrated into the side struts 5 if to be coupled implements are in a category that deviates from the set category.
FIG. 2 shows an enlarged longitudinal section through a side strut 5 of FIG. 1 . The side strut 5 includes a single-action hydraulic cylinder with a cylinder housing 9 and a piston 16 . The cylinder housing 9 has a cylinder chamber 10 . At one end, the cylinder chamber 10 is closed by a base. At the other end, the cylinder chamber 10 includes a guiding bore 13 centered on the longitudinal axis 12 . An attaching bore 11 leads into the cylinder chamber 10 . A pressure agent line can be connected to the attaching bore 11 . The pressure agent line is either connected to the lifting mechanism of the tractor for the lower steering arms, or it is connected to a separate pressure source with incorporated control elements.
The first attaching means 6 , in the form of a ball eye, is attached to the cylinder housing 9 . A stripper 14 and a seal 15 , one positioned behind the other, are arranged at the end of the guiding bore 13 , remote from the first attaching means 6 . The piston 16 has a hollow cylinder 17 . The hollow cylinder 17 is closed at one end by a base 18 . The base face 18 point towards the interior of the hollow cylinder. The outer face of the hollow cylinder 17 , toward the base 18 , includes a groove which is engaged by a stop ring 23 . The stop ring 23 delimits the outward movement of the piston 16 out of the cylinder housing 9 .
FIG. 2 shows the piston 16 in its furthest moved-out position. The piston 16 is supported via the stop ring 23 against a corresponding face in the region of transition between the cylinder chamber 10 and the guiding bore 13 . A rod-shaped, especially tube-shaped setting element 20 , is received in the hollow cylinder 17 . The setting element 20 is adjustable along the longitudinal axis 12 . FIG. 2 shows the setting element 20 in its moved-in position relative to the piston 16 and the hollow cylinder 17 . The setting element 20 , via its first end face 21 , rests against the base face 19 .
The setting element 20 is guided relative to the hollow cylinder 17 by two guiding rings 26 , 28 . The guiding rings 26 , 28 are positioned on the outer face 24 of the hollow cylinder 17 . The first guiding ring 26 is arranged near the end of the hollow cylinder 17 . The end is removed from the base 18 . The first guiding ring 26 is guided on the inner face 25 of the hollow cylinder 17 . The first guiding ring 26 is also in contact with a securing ring 27 secured in the hollow cylinder 17 . Thus, the first guiding ring 26 cannot be moved out of the hollow cylinder 17 . The second guiding ring 28 is arranged near the base 18 and secured to the outer face 24 of the setting element 20 towards the base 18 by a securing ring 29 . The second guiding ring 28 is guided on the inner face 25 of the hollow cylinder 17 .
Spring means is arranged between the two guiding rings 26 , 28 . The spring means is in the form of a pressure spring 31 . The first end face 21 of the setting element is held by the pressure spring 31 in contact with the base face 19 . The pressure spring 31 is co-axially arranged around the setting element 20 and is arranged in the hollow cylinder 17 .
The setting element 20 includes a continuous bore centered on the longitudinal axis 12 . Part of the bore, starting from the second end face 22 of the setting element 20 , includes a threaded bore 30 . A threaded rod 32 is adjustably received in the bore 30 . In the moved-in condition of the setting element 20 , the threaded bore 30 , relative to the hollow cylinder 17 , is arranged with part of its length in the hollow cylinder 17 . In the moved-in condition, a small part of the setting element 20 axially projects beyond the end of the hollow cylinder 17 , which end faces away from the base 18 .
A holding device 35 is secured to the setting element near the second end. An actuating lever 33 is secured to the holding device 35 . The lever 33 is pivotable around the pivot axis 34 . In the inactive condition, which is shown in FIG. 2, the actuating lever 33 is positioned between two yoke arms of a first holding element 36 . The lever is held by the setting element 20 so as to be non-rotatable relative to the piston 16 . Thus, the setting element 20 cannot be rotated around the longitudinal axis 12 . Furthermore, the threaded rod 32 carries the second attaching means. The second attaching means 7 attaches to a lower steering arm. The telescopic design achieves an extremely short installation length.
While the above detailed description describes the preferred embodiment of the present invention, the invention is susceptible to modification, variation and alteration without deviating from the scope and fair meaning of the subjoined claims. | A side strut ( 5 ) for a lower steering arm of a tractor has a single-action hydraulic cylinder with a cylinder housing ( 9 ) and a piston ( 16 ). The piston includes a hollow cylinder ( 17 ) with a base ( 18 ). In the hollow cylinder ( 17 ), a rod-shaped element ( 20 ) is adjustable against the force of a spring from a moved-in position into a moved-out position. Because the piston ( 16 ) and the setting element ( 20 ) move in the same direction, it is possible to achieve a telescopic design which leads to a short installation length which, in turn, results in a more advantageous buckling strength. | 0 |
FIELD OF INVENTION
[0001] The present invention relates to the general art of escalators and moving walkways, and to the particular field of escalator and moving walkway handrails.
BACKGROUND OF THE INVENTION
[0002] Escalators and/or moving walkways are installed inside and or outside of buildings or structures that have multiple floors. Escalators are used in department stores, office buildings, airport terminals, subway and train stations, arenas, convention centers and hotels to move people in large numbers up or down to one floor to another floor.
[0003] Moving walkways, which are a horizontal traveling type of escalator, are used on single floor level to speed the travel of pedestrians along walkways along a horizontal or inclined plain.
[0004] The handrails associated with these assisted traveling systems serve as handgrips and are intended to prevent pedestrians from falling down or slipping.
[0005] The handrails are commonly made of rubber or a flexible composite material. Pedestrian's hands come in contact with the handrails and they deposit various bacteria, viruses and the like to the surface of the handrails that may be harmful to other pedestrians that touch the same contaminated area of the handrail. Bacteria and viruses continue to propagate on the handrails. Therefore handrails should be continually disinfected to prevent the spread of infectious microbes.
[0006] Presently, sanitary maintenance of the moving escalator and moving walkway handrails is attempting to being fulfilled by periodically cleaning the surfaces with neutral cleaning agents or antiseptic solutions. It is clear that the railing surfaces are not disinfected between the periodic cleaning intervals.
[0007] As these moving hand rails must be frequently cleaned manually, there is a problem in that the maintenance and cleaning supplies are becoming very expensive. In addition, since the cleaning work cannot positively sterilize and disinfect the handrails consistently after each persons usage travelers are exposed to hazards such as disease causing bacteria and virus infections due to the bacteria and virus existing on the handrails.
[0008] Accordingly, escalator and moving walkway handrails in both public and private structures are either left dirty, or at best, taken care of by occasional cleaning. Without proper protection and safeguards, the general public is constantly subjected to these unsanitary conditions.
[0009] Such a situation is not only costly but very detrimental from the standpoint of public safety.
SUMMARY OF THE INVENTION
[0010] The present invention is a device for enclosing the top and two sides of escalator and or moving walkway handrails for the purpose of disinfecting and killing deposited microbes during normal operation. The device uses a UV Germicidal Lamp to kill the virus and bacteria without any foreign objects or chemicals touching the handrail. As the handrail passes through the device it passes through a chamber that contains the UV Germicidal lamp.
[0011] Exposure to the UV light causes damage to the nucleic acid of microorganisms by forming covalent bonds between certain adjacent bases in the DNA. The formation of such bonds prevents the DNA from being unzipped for replication, and the organism is unable to reproduce. In fact, when the organism tries to replicate, it dies. The close proximity of the UV Germicidal lamp to the handrails of the escalator and or moving walkways kills most microorganisms in micro seconds. The UV Germicidal lamp device is contained in a metal housing that is attached to the substructure of the escalator and or moving walkway using a mounting bracket on each side of the escalator.
OBJECTS OF THE INVENTION
[0012] The object of the present invention is to provide a device for continuously disinfecting escalator and/or moving walkway handrails during normal operation without shutting down the unit.
[0013] Another object of the invention is to continuously disinfect and sanitize the escalator and or moving walkway handrails without any cleaning material products or substances touching or be in direct contact with the handrails.
[0014] Another object of the invention is to provide a device that eliminates the cost of cleaning supplies and materials used in the maintenance of escalator and or moving walkway handrails.
[0015] Another object of the invention is to reduce the labor costs involved in the cleaning and maintenance of escalator and or moving walkway handrails.
[0016] Another object of the invention is to prevent the spread of infectious bacteria and viruses from one person to another person when harmful microorganisms are deposited on the surface of escalator and or moving walkway handrails by persons holding on to the handrails when traveling on the escalator and or moving walkways.
[0017] In one embodiment, the present invention is a system and method for sterilization of handrails comprising:
[0000] providing an UV light sterilization unit; identifying a placement position for said unit, said position being proximately located to a moving escalator or walkway handrail;
placing said unit in said placement position; activating said UV light unit, wherein said activation sterilizes said handrail continually while said handrail is in motion.
[0018] The system provides UV light at a wavelength from 240-280 nm, preferably at a wavelength of 254 nm.
[0019] The unit provides continuous UV light.
[0020] In one embodiment, the unit provides UV light in regular pulses.
[0021] Preferably, the unit provides a degree of microbial inactivation by light intensity and exposure time at 2,000 to 8,000 μW·s/cm 2 .
[0022] The intensity and exposure time is correlated such that said unit provides said intensity and exposure time relative to said moving handrail.
[0023] The unit is positioned such that it provides an unobstructed light pathway to said handrail, and preferably is in a position where it is not accessible to users of said handrail.
[0024] In one embodiment, the unit has one or more detectors to optimize efficiency. The detectors can include detection means to measure the level of microorganisms on said handrail and automatic adjustments of UV light duration and intensity based on said measurements.
[0025] The unit can also include means to measure the speed of said handrail and adjusts light and intensity based on handrail speed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a perspective drawing of the device housing
[0027] FIG. 2 is a end view cut away drawing of the device
[0028] FIG. 3 is a perspective drawing of the device mounted on an escalator
[0029] FIG. 4 is a perspective drawing of the device mounted on a moving walkway.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] FIG. 1 shows the preferred embodiment of the UV Germicidal Lamp Housing 101 as being rectangular with a slot cavity configured to the shape of the handrail 401 and running down one side allowing the handrail to pass through and over said cavity, in close proximity to the UV Germicidal Lamp 60 . The main components of the invention are the outer case 10 to house the components. Outer case 10 is positioned on or proximate to the escalator substructure 210 and or moving walkway substructure 105 with a support bracket 15 . On each end of the housing 101 are the shades 20 constructed and arranged to prevent UV rays from escaping through the ends of the housing 101 as the handrail 401 passes through the device. This construction refers to the shape, configuration, and material composition to restrict the path of UV light. The UV radiation is provided by a UV Germicidal Lamp 60 surrounded by a linear parabolic reflector 70 which is made of metal with a highly polished surface to maximize and direct the UV rays onto handrail 401 . The Lamp 60 is controlled by an On/Off service switch 40 to control the power during service.
[0031] The UV Germicidal Lamp Housing 101 also contains a power safety switch 50 to prevent the UV Germicidal Lamp 60 from turning on during servicing or when the housing 101 is removed from the escalator substructure.
[0032] The UV Germicidal Lamp Housing 101 also has an observation window 80 to visually check the operation of the lamp. This opening is covered by a UV lens 90 to prevent injury to servicing personnel eyes.
[0033] The UV Germicidal Lamp Housing 101 also has a motion sensor 55 that detects movement of the handrail 401 . While the escalator and moving walkway handrails 401 are in motion the UV Germicidal Lamp 60 remains on. Should the escalator and moving walkway stop for any reason the UV Germicidal Lamp 60 is turned off.
[0034] FIG. 2 shows the UV Germicidal Lamp Housing 101 cut away from one end, exposing the main components of the unit. The escalator and or moving walkway handrail 401 passes through and over the shade 20 in the configured slot area 75 in the UV Germicidal Lamp Housing 101 , exposing the handrail 401 directly to the UV Germicidal Lamp 60 destroying all surface microbes. The shade 20 prevents the UV light from escaping from the UV Germicidal Lamp Housing 101 to prevent harm to service personnel. The UV linear parabolic reflector 70 is highly polished to reflect the rays towards the handrail 401 . The UV Germicidal Lamp Housing 101 is mounted to the escalator and or moving walkway substructure 210 using mounting bracket 15 beneath the fascia panel 220 . Power for the unit is controlled by a power switch 40 .
[0035] FIG. 3 shows the UV Germicidal Lamp Housing 101 mounted to the escalator substructure 210 for each handrail 401 on each side of the escalator 201 with a mounting bracket 15 . The unit is positioned beneath the fascia panel 220 in the service area of the escalator 201 . Every time the handrail 401 passes through the UV Germicidal Lamp Housing 101 and is exposed to the UV Germicidal Lamp 60 the UV radiation emitted kills the viruses and bacteria on the surface of each handrail 401 .
[0036] FIG. 4 shows the UV Germicidal Lamp Housing 101 mounted to the moving walkway substructure 105 for each handrail 401 on each side of the moving walkway 301 with a mounting bracket 15 . The unit is positioned beneath the fascia panel 220 in the service area of the moving walkway 301 . Every time the handrails 401 passes through the UV Germicidal Lamp Housing 101 and is exposed to the UV Germicidal Lamp 60 the UV radiation emitted kills the viruses and bacteria on the surface of each handrail 401 .
[0037] While the invention has been described in its preferred form or embodiment with some degree of particularity, it is understood that this description has been given only by way of example and that numerous changes in the details of construction, fabrication, and use, including the combination and arrangement of parts, may be made without departing from the spirit and scope of the invention. | A system for sterilization of handrails having a UV light sterilization unit; a placement position for said unit, said position being proximately located to a moving escalator or walkway handrail; and activating said UV light unit, wherein said activation sterilizes said handrail continually while said handrail is in motion. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
Not applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not applicable.
REFERENCE TO A “MICROFICHE APPENDIX”
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Present Disclosure
This disclosure relates generally to devices for disabling a pursued vehicle including devices that are placed under the vehicle while in motion, and more particularly to a device that is projected through the air to penetrate a tire of the fleeing vehicle.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
In dealing with vehicles that are fleeing from law enforcement a number of solutions have been invented. Typical among them are tire deflating devices which are used in an attempt to disable a fleeing vehicle while, at the same time, maintaining safety for the law officers, the general public and the individuals that are being pursued. Numerous devices have been invented to deflate the tires of a motor vehicle by placing upwardly-extending metal spikes in the path of the vehicle. Such devices can be used by law enforcement officers to stop or slow target vehicles. One such device is disclosed in Kilgrow et al, U.S. Pat. No. 5,253,950. This device comprises a tire deflator which can be extended from a collapsed condition to place an array of upwardly extending metal spikes over a section of roadway from approximately 10 to 25 feet wide. Other devices using spikes or the like are disclosed in U.S. Pat. No. 5,330,285 and U.S. Pat. No. 5,820,293. These and similar devices are typically deployed by hand; i.e. they are carried to a site where the target vehicle is expected and placed in the roadway in the hope that the vehicle will drive over the extended spikes.
Further solutions include Pacholok et al, U.S. Pat. No. 5,839,849 which describe a mechanical tire deflating device deployed by ejection forwardly from the front of a pursuing vehicle to a position beneath a second vehicle immediately in front of the law enforcement vehicle. According to the patent, a folded tire deflator is deployed forwardly of the law enforcement vehicle by a spring loaded launcher mounted on the front of the law enforcement vehicle. The deflator carries spikes which penetrate the tires of the target vehicle. Abukhader, U.S. Pat. No. 5,611,408 describes another vehicle disabling device. The patent discloses a folded tire deflating device that is deployed from a launcher mounted on the underside of the front of a law enforcement vehicle. Upon deployment spikes are extended in such a way as to penetrate the tires of a target vehicle. A laser beam is used to aim the tire deflator. Both the Pacholok et al and Abukhader devices pose a threat that the pursuing vehicle will run over the tire deflator which has been deployed from it.
Further related references include: De Sylva, U.S. 2005/0038592, discloses a system for selectively disabling a vehicle. In the illustrative embodiment, the system adapted to prevent high-speed automotive chases. The system includes a first mechanism for locating vehicle to be disabled. A second mechanism launches a disabling projectile toward the vehicle. A third mechanism employs the projectile to disable the vehicle by suffocating an engine of the vehicle or otherwise compromising the fuel/air mixture. In a specific embodiment, and an infrared guidance system guides the projectile toward a muffler of the vehicle, and a muffler-plugging agent incorporated within the projectile plugs a muffler. Holder, U.S. Pat. No. 5,067,237, discloses a battering ram for forcible entry through a door that has a pointed end with barbs to enable the door to be hooked and pulled outward. The barbs will swing between contracted and expanded positions. This spring biases the barbs to the expanded position. The barbs are conical and define a cone with the same taper as the pointed tip when the barbs are collapsed. One end of the battering ram may have a loop for attaching to a line connected to a vehicle. Also, one end of the battering ram may have a battering plate or may have a bar for prying burglar bars outward. Amiand et al., U.S. Pat. No. 5,480,108, discloses an anchoring system using a harpoon secured under a helicopter and a grid platform that includes a shaft, having near its end, fingers oriented and movable radially between a retracted position and an extended position. The shaft includes a device for moving and retaining the fingers in the extended position. The device acts from a state activated in response to the penetration into the grid. It furthermore includes structure for unlocking the fingers and resetting the moving and retaining device. Harpoons including such catching heads, which have the advantage of being light and simple in construction, and capable of being adaptable to all types of helicopters are also contemplated. Fischbach, U.S. Pat. No. 6,246,323, discloses a tagging system for tagging a target vehicle consists of a tracking device, a launching device, a receiving device and a monitor to display the position of the target vehicle. The tracking device includes a tracking chip contained in a pliable carrier, and is stored in and launched from a housing mounted in a pursuit vehicle's grill. The launching device includes a firing pad slidably retained within the housing and spring mounted to the housing rear end. Pad forks in communication with a solenoid retain the firing pad near the housing rear end until two switches in the pursuit vehicle are sequentially activated, whereupon the tracking device emits a tracking signal, the solenoid is activated, releasing pad forks and thereby launching the tracking device towards the target vehicle. The tracking device is in free flight until it impacts (“tags”) the surface of the fleeing vehicle, to which it adheres by means of the carrier. The tagged vehicle thus emits a tracking signal which represents the location of the tagged vehicle, which is received by the receiving device and appears as an image on a monitor within the pursuit vehicle. The system can work with a Global Positioning Satellite system or similar navigational or communications satellites. The need to maintain constant visual contact is reduced, and thereby the risk of injury to the public and parties involved in the hot pursuit of a fleeing vehicle. Limingoja, U.S. Pat. No. 6,176,519, discloses a method for forced stopping of a second vehicle by using a first vehicle that includes equipment in the front end of the first vehicle which can be used to engage sheet metal structures, and the front end of the first vehicle is driven into the rear of the second vehicle so that the equipment in the front end of the first vehicle engages the sheet metal structure in the rear of the second vehicle. whereby the second vehicle can be stopped by the first vehicle. The equipment used can include a turning body part and a tip part with gripping device attached to the body part in a detachable way. The gripping device can contain a tip which penetrates the sheet metal structure. The method and the equipment according to the invention can be used to stop a fleeing vehicle without the need to drive beside it or to pass it or to try to force it off the road. Lowrie, U.S. Pat. No. 6,527,475, discloses a system for the selective deployment of a tire deflation device. The system incorporates the use of a mounted housing combined with a compressed gas propulsion source for ejecting a collapsed tire deflation device that is attached to the housing with a tether line. One embodiment of the invention is to have a dual system mounted to the underside of a vehicle behind the rear tires. Each system is pointed in an opposite direction to achieve left or right side deployment. A set of control switches mounted inside the vehicle near the operator can be depressed for either left or right side ejection. Upon ejection the tire deflation device projects laterally away from the vehicle. A remote trigger is disclosed. Ramirez, U.S. Pat. No. 6,623,205, discloses a vehicle disabling device for disabling a fleeing vehicle that has a carriage that is projected from a launch platform using a plurality of elongate extension tubes. The plurality of elongate extension tubes are pneumatically actuated with a tank of compressed air operably connected to the plurality of elongate extension tubes with a pneumatic hose. The carriage includes a pair of carriage wheels and is adapted for rectilinear movement in front of a pursuit vehicle. The carriage also includes a first arm and a second arm connected pivotally to the carriage. A plurality of spikes are disposed along the first and second arms, adapted to puncture the tires of the fleeing vehicle once the fleeing vehicle has run over one of the first and second arms. Brydges et al., U.S. Pat. No. 6,650,283, discloses an invention that is directed to a system for tracking a fleeing vehicle comprising a frangible tracking projectile and a launcher to propel and attach the tracking projectile to the fleeing vehicle. The launcher is a handheld or vehicle mounted pneumatic gun that uses high pressure gas to fire the projectile at the fleeing vehicle. The tracking projectile comprises an outer plastic casing that holds a GPS receiver, a radio transponder and a power source in an adhesive mixture. When the tracking projectile strikes its target, the plastic casing shatters allowing the adhesive substance to attach the GPS receiver, radio transponder and power source to the fleeing vehicle. Heibel, U.S. Pat. No. 6,715,395, discloses a pursuit vehicle that carries a remote targeting device in a suitable position to identify a target area on an inflated tire of the pursued vehicle and a launcher for a projectile suited to puncture an inflated tire of a pursued vehicle, from a position trailing the pursued vehicle. The projectile launcher launches the projectile when suitably triggered. An electrically operated, remote triggering device selectively causes the projectile launcher to launch the projectile at the identified target area, puncturing and thereby disabling the tire of the pursued vehicle.
The related art described above discloses several systems for stopping or identifying a fleeing vehicle including the use of spike strips and other puncture devices. However, the prior art fails to disclose a tethered flying projectile launched from a pursuing vehicle. The present disclosure distinguishes over the prior art providing heretofore unknown advantages as described in the following summary.
BRIEF SUMMARY OF THE INVENTION
This disclosure teaches certain benefits in construction and use which give rise to the objectives described below.
The present invention is a pursuit vehicle used to disable a pursued vehicle by puncturing one of its tires so that the pursued vehicle is disabled but not likely to go out of control. The pursuit vehicle carries a projectile housed within a launcher mounted on its front end. The projectile is able to be directed at high speed from the launcher toward a tire of the pursued vehicle. A tether line is coiled about a tether reel within the chase vehicle is fixed to the projectile. The line is of a flexible but high tensile strength material such as a steel alloy, a titanium alloy, a polymer such as nylon, or of carbon fiber, and may be made of an elastic cord so as to stretch as necessary while still restraining the projectile from free movement. As the projectile moves toward the pursued vehicle the tether reel is motor driven to play out the line so that the line does not present a drag on the projectile and so that the projectile strikes the tire with maximum force. The projectile has folded barbs that extend once the projectile has entered the tire and which keep the projectile from flying out of the tire due to centripetal force. Being penetrated, the tire quickly looses pressure and deflates while the tether line wraps itself around the wheel's axle and brakes which can cause the wheel to stop spinning. Should the projectile miss the target, the tether prevents it from endangering the public and makes it relatively easy to retrieve since the motor driven reel is able to be reversed thereby drawing-in the line. Also, since the projectile is relatively small it does not present a significant danger to the pursuing vehicle should it run over the projectile.
A primary objective inherent in the above described apparatus and method of use is to provide a relatively safe way to deflate a tire of a fleeing vehicle.
A further objective is to provide a means for targeting the fleeing vehicle with a projectile.
A still further objective is to provide a means for launching the projectile at the tire, penetrating the tire and preventing the projectile from pulling out of the tire.
Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the presently described apparatus and method of its use.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
Illustrated in the accompanying drawing(s) is at least one of the best mode embodiments of the present invention In such drawing(s):
FIG. 1 is an elevational view of the presently described apparatus shown in position for use with a fleeing vehicle;
FIG. 2 is a further elevational view thereof showing the manner in which the apparatus is executed;
FIG. 3 is an interior view thereof showing the use of a further element of the apparatus; and
FIG. 4 is a partial vertical sectional view of a tire being punctured by a projectile of the apparatus.
DETAILED DESCRIPTION OF THE INVENTION
The above described drawing figures illustrate the described apparatus and its method of use in at least one of its preferred, best mode embodiment, which is further defined in detail in the following description. Those having ordinary skill in the art may be able to make alterations and modifications what is described herein without departing from its spirit and scope. Therefore, it must be understood that what is illustrated is set forth only for the purposes of example and that it should not be taken as a limitation in the scope of the present apparatus and method of use.
Described now in detail is an apparatus for disabling a pursued vehicle 10 from a following pursuing vehicle 30 by puncturing the pursued vehicle's tire 12 with a projectile 20 . The projectile 20 is housed within a projectile launcher 22 , preferably of tubular shape which is mounted on a front end 32 of a chase vehicle 30 , such as a police cruiser, as shown in FIG. 1 . The projectile 20 initially is fitted within launcher 22 until it is directed at high speed from the launcher 22 toward the tire 12 of the pursued vehicle 10 , as shown in FIG. 2 . A tether line 42 is stored in a coiled configuration within the pursuing vehicle 30 and may be coiled about a tether reel 40 or merely in a free-play-out coil as is well known. The free end 42 ′ of the line 42 is fixed to the rear end 24 of the projectile 20 . The line 42 is preferably constructed of a steel alloy, a titanium alloy, a polymer such as nylon or carbon fiber, i.e., the line 42 is highly flexible and has high tensile strength. As the projectile moves away from the chase vehicle 30 , its coiled portion plays out as best shown in FIG. 2 but is always tethered to the chase vehicle 30 .
The launcher 22 provides a propulsor 60 positioned and adapted for propelling the projectile 20 from the launcher 22 forward of the chase vehicle 30 . The propulsor 60 may be any means for shooting the projectile 20 out of the launcher 22 including a compressed gas canister as is well known in paint ball projection. The propulsor 60 may alternately be a compressed expansion spring which, when a retaining latch is withdrawn by a solenoid for instance, the spring is freed to propel the projectile 20 from the launcher. Finally, an explosive charge may be detonated for rifle-like action in projecting the projectile 20 . The propulsor may function in any of the above ways for others well known to those of skill in the projectile arts including guns, cannon and rockets. For example, Fischbach, U.S. Pat. No. 6,246,323 and Abukhader, U.S. Pat. No. 5,611,408 each teaches a means for launching a projectile in a manner similar to the present invention, and are therefore incorporated herein by reference for such teaching.
A video camera 50 is mounted on the launcher 22 so as to sight forward of the chase vehicle 30 , see dashed line 51 in FIG. 1 , in acquiring a video image 52 as shown in FIG. 3 . However, in this disclosure and claims, the usage “video camera” shall also mean equivalents thereof such as a helmet mounted sighting device and controller well known in military applications, a laser sight, a thermal imager, a radar locator and other known sighting devices well known in the art. In the preferred embodiment, a video display 54 displays the image 52 within the chase vehicle 50 , i.e., the video image 52 is communicated from the video camera 50 to the video display 54 so that it can be viewed by the occupants of the chase vehicle 30 . Therefore, the tire 12 of the pursued vehicle 10 may be easily targeted by the occupants of the chase vehicle. This is accomplished by using a reticle or cross hairs either printed on the lens of the video camera 50 , or added into the video image 52 electronically as is well known in the art. The cross hairs appear on the video display 54 as shown in FIG. 3 .
Targeting the launcher 22 and projectile 20 merely involves properly positioning the chase vehicle 30 relative to the pursued vehicle 10 . When the chase vehicle 30 is too far from the pursued vehicle 10 , the horizontal cross hair will be below the image of tire 12 that appears on the video display 54 , and when the vehicle 30 is too close, the horizontal cross hair will be above the tire's image. This is corrected using the gas pedal and brake pedal appropriately in the chase car 30 until the horizontal crosshair is positioned as shown in FIG. 3 . When the vertical cross hair is positioned to the left or right of the tire image correction is made using the steering wheel in the chase vehicle 30 to further correct alignment.
Clearly, the targeting method used in the present apparatus may use a wave energy transceiving device based on one or more of: video, radar, sonar, radio frequency, ultrasonic sound technique.
When the cross-hairs are on the tire's image, as shown in FIG. 3 , the launcher 22 and projectile 20 are in position to direct the projectile 20 into the tire 12 , as shown in FIG. 2 . To accomplish this, a propulsor enabler 62 within the chase vehicle 30 as shown in FIG. 3 , and which is in communication with the propulsor 60 , is manually enabled thereby actuating the propulsor 60 and launching the projectile 20 . Enabler 62 is preferably a solenoid circuit actuated by the button on the dashboard shown in FIG. 3 . Such a solenoid circuit is able to puncture a gas canister, release a spring, or actuate a fuse to detonate a charge, etc. as would be well within the skill of those in the art.
Preferably, a reel motor 44 , an electric motor operating from the 12 volt battery of the chase vehicle, is engaged with the tether reel 40 for driving the tether reel 40 to unwind the tether line 42 simultaneously with the flight of the projectile 20 . Since the acceleration and velocity of the projectile is determinant by experimentation, a motor circuit for driving the tether reel 30 at an associated rotational speed to allow the tether line 42 to be delivered to the projectile 20 . Both the propulsor 60 as well as the reel motor 44 are actuated simultaneously in this case by the propulsor enabler 62 .
Of necessity, the projectile 20 has plural pivotal barbs 25 positioned thereon, the barbs 25 adapted for swinging outwardly from the projectile 20 upon deceleration thereof because the barbs are hinged forward on the projectile 20 with the barbs 25 extending rearwardly on the projectile 20 . As the projectile 20 penetrates the tire 12 it quickly decelerates and the barbs 25 fly outwardly as shown in FIG. 4 . The barbs 25 are incapable of withdrawing to their initial positions because as the projectile attempts to pull out of the tire casing, the barbs 25 prevent such pull out and prevent the barbs 25 from folding to their original positions. Therefore, the projectile is secured within the tire 12 .
The enablements described in detail above are considered novel over the prior art of record and are considered critical to the operation of at least one aspect of the apparatus and its method of use and to the achievement of the above described objectives. The words used in this specification to describe the instant embodiments are to be understood not only in the sense of their commonly defined meanings, but to include by special definition in this specification: structure, material or acts beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, then its use must be understood as being generic to all possible meanings supported by the specification and by the word or words describing the element.
The definitions of the words or drawing elements described herein are meant to include not only the combination of elements which are literally set forth, but all equivalent structure, material or acts for performing substantially the same function in substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements described and its various embodiments or that a single element may be substituted for two or more elements in a claim.
Changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalents within the scope intended and its various embodiments. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements. This disclosure is thus meant to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted, and also what incorporates the essential ideas.
The scope of this description is to be interpreted only in conjunction with the appended claims and it is made clear, here, that each named inventor believes that the claimed subject matter is what is intended to be patented. | A pursuit vehicle carries a projectile housed within a launcher mounted on its front end. The projectile is able to be directed at high speed from the launcher toward a tire of a pursued vehicle. A tether line is coiled about a tether reel within the chase vehicle and is fixed to the projectile. The projectile has folded barbs that extend once the projectile has entered the tire and which keeps the projectile from flying out of the tire due to centripetal force. Being penetrated, the tire quickly looses pressure and deflates while the tether line wraps itself around the wheel's axle and brakes which can cause the wheel to stop spinning. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a dewatering apparatus of an automatic washing machine, and more particularly, to a dewatering apparatus in which an unbalance of a washing tub and an opening of a door can be accurately sensed to control them while performing a dewatering function after completing wash and rinse cycles in the washing machine.
2. Discussion of the Related Art
A conventional automatic washing machine is shown in FIG. 1 to FIG. 4. Since unbalance sensing switch 4a is mounted at one side of a top cover 1a on a body 16, switching points 24a,25a of first and second terminals 24,25 are coupled by upward movement of a door lever 22 and a switching lever 23 when a door 5a closes, to switch on current as shown in FIG. 2a.
As shown in FIG. 2a, if a washing tub 3 oscillates during a dewatering process, the washing tub 3 bumps against an outer tub 15. At the same time, unbalance sensing lever 26 is deflected by a predetermined distance L by means of the outer tub 15. Likewise, the switching points 24a,25a of the first and second terminals 24,25 are isolated from each other by the action of switching lever 23 to switch off current as shown in FIG. 2b.
Laundry may lean to one side of the washing tub 3 while tub 3 spins to dewater the laundry, after washing and rinsing. The washing tub 3 therefore becomes unbalanced to thereby causing the washing tub 3 to bump against the outer tub 15. At the same time, the outer tub 15 pushes the unbalance sensing lever 26. As a result, the switching points 24a,25a of the first and second terminals 24,25 switch off for a certain time t.
Further, since the door lever 22 is not displaced when door 5a of the washing machine opens as shown in FIG. 2, the switching points 24a,25a of the first and second terminals 24,25 remain switched off until the door 5a closes.
Meanwhile, as shown in FIG. 3, a low signal is input to the microprocessor 21 when the unbalance sensing switch 4a is closed, while a high signal is input to the microprocessor 21 when the unbalance sensing switch 4a opens. Thus, when a signal having a predetermined level is input to the microprocessor 21 as shown in FIG. 4, an unbalance of the washing tub 3 is sensed when the signal input time is shorter than a certain threshold time t of about 80-200 ms. The opening of the door 5a is sensed when the signal input time is longer than the threshold time.
However, since the opening of the door 5a and the unbalance of the washing tub 3 are simultaneously sensed by the unbalance sensing switch 4a as above, it is difficult to sense the opening of the door 5a when primarily using the unbalance sensing switch 4a for sensing the unbalance of the washing tub 3. On the other hand, it is difficult to sense the unbalance of the washing tub 3 when primarily using the same for sensing the opening of the door 5a. In addition, the sensing performance depends on position of the unbalance sensing switch 4a.
Moreover, once the unbalance sensing switch is fixed to the washing machine, it is hard to change its configuration and position. If a relatively large amount of laundry is loaded into the washing tub 3, the position of the outer tub 15 is lower than a bottom portion of unbalance sensing lever 26 because of laundry's weight and a buffer force of a damper 27 mounted between a top portion of the body 16 and a bottom portion of the outer tub 15. This makes sensing the unbalance of the washing tub 3 impossible or causes deformation of the unbalance sensing lever 26 in case of its restoration as it is to occur malfunction of the sensing function of the unbalance. It is also likely for the unbalance sensing lever 26 protruding towards a lower portion of the top cover 1a to become deformed while transferring and assembling the top cover 1a, and while disassembling the machine for assembly and change of the washing machine.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a dewatering apparatus of an automatic washing machine that substantially obviates one or more of the limitations and disadvantages of the related art.
An another object of the present invention is to provide a dewatering apparatus in an automatic washing machine that is smaller and less expensive to manufacture by simplifying its configuration so as to reduce a required space for mounting.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the dewatering apparatus of an automatic washing machine according to the present invention includes: an unbalance sensor mounted on a controller mounted into a top cover, for sensing an unbalance of a washing tub during a dewatering process a magnet mounted on a door, for sensing an opening of the door during the dewatering process; and a hall sensor mounted on an another controller more adjacent to the magnet, for sensing the on/off state of a switch by means of the magnetic field of the magnet in the event of opening or closing of the door.
The watering control method according to the present invention includes the steps of: initiating a variable state relating to a dewatering function and determining levels of input signals input to input ports of a microprocessor; interrupting the dewatering cycle in progress by detecting opening of a door if the level of input signals to the microprocessor are high and, at the same time, stopping a progressing state of an indicative portion indicative of the dewatering cycle in progress; continuing the dewatering cycle if the input signals are low; measuring an elapsed time between a starting time of the dewatering function and a time at which the unbalance of the washing tub is sensed for a certain time since the dehydrating function has progressed, and comparing and determining whether or not it is less than a threshold time; and performing a sub-routine which senses the unbalance of the washing tub where the sensing time of the unbalance is less than the threshold time, and determining progressing time of the dehydrating cycle after accumulatively counting the sensing time of the unbalance and storing it into a memory in case where it is more than a certain time.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together will the description serve to explain the principles of the drawings:
In the drawings:
FIG. 1 shows a longitudinal section of a conventional automatic washing machine;
FIGS. 2a and 2b show longitudinal sections showing operation of an unbalance sensing switch of FIG. 1;
FIG. 3 shows an operation circuit of an unbalance sensing switch of FIG. 1;
FIG. 4 is a flow chart showing sensing states of an unbalance of a washing tub and an opening of a door during performing a dewatering function in a conventional automatic washing machine;
FIG. 5 is a partial sectional view showing a dehydrating apparatus of an automatic washing machine according to the present invention;
FIG. 6 is a perspective view showing an unbalance sensor of FIG. 5;
FIG. 7 is a longitudinal sectional view showing an unbalance sensor of FIG. 6;
FIGS. 8a, 8b and 8c are longitudinal sectional views showing different embodiments of an unbalance sensor according to the present invention;
FIG. 9 is an operational system of an automatic washing machine according to the present invention;
FIG. 10 is a detailed circuit diagram of an outer signal input portion of FIG. 9;
FIG. 11 is a flow chart illustrating a dewatering control method of an automatic washing machine according to the present invention; and
FIG. 12 is a flow chart illustrating an unbalance sensing operation of a washing tub of FIG. 11.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
Referring to FIG. 5, an unbalance sensor 4 for sensing an unbalance of a washing tub 3 while performing a dewatering function is mounted on a lower portion of a door controller 2 mounted into a top cover 1. A magnet 6 is mounted at the end of a door 5 to sense whether the door 5 is opened during performing the dehydrating function. A hall sensor 7 mounted on door controller 2 adjacent to the magnet 6 senses switching on or off responsive to opening/closing of the door 5 by means of the magnetic field of the magnet 6.
Referring to FIG. 6, a signal transmitting hale 9 is formed at the center of a first case 8 in the unbalance sensor 4. A cut-off plate 10 is mounted at a slope of a certain angle to correct a portion which is not horizontal due to a slope of the bottom when the unbalance sensor 4 is mounted. A second case 11 is joined with an upper portion of the first case 8. A signal receiving hole 12 is formed a the center of an upper portion of the second case 11. An infrared ray diode 13 is mounted at a lower portion of the signal transmitting hole 9 so as to emit an; infrared beam. A photo transistor 14 is mounted on an upper portion of the signal receiving hole 12 to receive the optical beam. A ball-shaped roller 17 is rolls on an upper portion of the cut-off plate 10, and stops the dewatering cycle by sensing the unbalance of the washing tub 3. The roller 17 is moved by any impact and oscillation occurring when outer tub 15 bumps against body 16 the washing tub 3 leans to one side during the dewatering cycle. As a result of displacement of the roller 17, the beam from infrared ray diode 13 reaches the photo transistor 14 so that the unbalance of the washing tub 3 is sensed. A plurality of roller controlling jaws 18 are formed at peripheral sides on an upper portion of the cut-off plate 10 to prevent the roller 17 from continually rotating and to guide it towards the signal transmitting hole 9 when where the outer tub 15 repeatedly bumps against the body 16.
Referring to FIG. 7, the dehydrating apparatus according to the present invention permits a normal dewatering cycle by preventing the beam emitted from the infrared ray diode 13 from being transmitted to the photo transistor 14 since the roller 17 is disposed on the center of the signal transmitting hole 9 when the washing tub sits normally during the dewatering function. The dewatering cycle is compulsorily stopped by transmitting the beam emitted from the infrared ray diode 13 to the photo transistor 14 when the roller 17 is displaced along the roller controlling jaws 18 when a strong oscillation occurs in the outer tub 15 due to a malfunction of the washing tub during the dewatering cycle.
A plurality of the roller controlling jaws 18 are formed at peripheral sides on the upper portion of the cut-off plate 10 to prevent the roller 17 from excessively rolling along an inner side of the second case 11 when the outer tub 15 successively bumps against the body 16.
Further, the cut-off plate 10 is disposed on the upper portion in the first case 8 at a slope of a certain angle θ (see FIG. 7) based on the signal transmitting hole 9. This allows a portion, which is not horizontal due to a slope of the bottom, to be desirably corrected when the unbalance sensor 4 is mounted into the washing machine or the washing machine is mounted on the bottom with a slope.
The other embodiments of the unbalance sensor according to the present invention will be described with reference to FIGS. 8a, 8b and 8c.
Referring to FIG. 8a, the infrared ray diode 13 and the photo transistor 14 are mounted adjacent to one another to have a certain angle relative to the lower portion of the signal transmitting hole 9 and the bottom of the first case 8. The optical beam emitted from the infrared ray diode 13 is reflected by the roller 17 to turn on the photo transistor 14 so that the unbalance is sensed during the dewatering cycle.
Referring to FIG. 8b, a press switch 19 is mounted on the bottom of the first case 14 and the lower portion of the signal transmitting hole 9 to sense the unbalance in response to a press state by means of the roller's own weight during the dewatering cycle.
Referring to FIG. 8c, switching points 20 are disposed between the bottom of the first case 8 and the cut-off plate 10. The switching points 20 are switched on or off depending on the movement of the roller 17 so that the unbalance is sensed during the dewatering cycle.
To sense the opening of the door 5 during the dehydrating function, the magnet 6 is mounted at the end of the door 5 and the hall sensor 7 is mounted at the door controller 2 more adjacent to the magnet 6. Thus, the hall sensor 7 is turned on by the magnetic field of the magnet 6 when the door 5 is closed. The hall sensor 7 is turned off when the magnetic field of the magnet 6 does not the hall sensor 7 when the door 5 opens.
A dewatering control circuit used by the dewatering apparatus of the automatic washing machine according to the present invention will be described with reference to FIG. 9 and FIG. 10.
Referring to FIG. 9, the dewatering control circuit includes a power supply 32 for supplying the microprocessor and peripheral circuits with power by converting AC 220V to DC 5V, a buzzer driving portion 33 indicating an operation state of the washing machine with sound, an indicative portion 34 indicative of the operation state of the washing machine, a key input portion 35 for enabling an appropriate key input, an outer interrupt portion 36 for determining an operation time of the microprocessor 31 in response to frequencies in common use and controlling the other operation time, a reset portion 37 for stabilizing the operation of the microprocessor 31 in the event of power on or off, an oscillating portion 38 for supplying the microprocessor 31 with a clock signal required for its operation, an outer signal input portion 39 for inputting a sensing signal from the unbalance sensor 4 to the microprocessor 31, and a laundry sensing portion 40 for sensing the amount of laundry to determine the amount of water supplied to the washing machine.
Referring to FIG. 10, the outer signal input portion 39 includes the respective driving circuits having the unbalance sensor 4 connected to a first input port IN0, the press switch connected to a second input port IN1, and the door controller 2 connected to a third input port IN2.
In the driving circuit of the unbalance sensor 4, a power voltage Vcc is applied to the infrared ray diode 13 and the photo transistor 14 through a plurality of resistors R1,R2. Thus, the photo transistor is turned on by the infrared beam emitted from the infrared ray diode 13, so that a signal amplified by the photo transistor 14 is applied to the first input port IN0 of the microprocessor 31 through a first switching transistor Q1. Since the roller 17 prevents the infrared beam emitted from the infrared ray diode 13 from being transmitted to the photo transistor 14 by blocking the signal transmitting hole 9 on the center of the cut-off plate 10 during a normal dewatering cycle as shown in FIG. 6, the photo transistor 14 is turned off and, at the same time, a first switching transistor Q1 is turned off. As a result, a low signal is applied to the first input port IN0 of the microprocessor 31.
On the contrary, when the roller 17 is moved from the signal transmitting hall 9 when unbalance occurs during the dewatering cycle, the infrared beam emitted from the infrared ray diode 13 is transmitted to the photo transistor 14. Thus, the photo transistor 14 is turned on so that the power voltage Vcc flows through the resistor R2 and the photo transistor 14, and a low voltage is applied to the base of the first switching transistor Q1, turning on the first switching transistor Q1. As a result, a high voltage of 5V is applied to the microprocessor 31.
Since the power voltage Vcc flows through a resistor R4 and the ground of one switching point of the press switch 19 the press switch 19 is switched on, a low voltage is applied to the microprocessor 31. On the other hand, a high voltage level is applied to the second input port IN1 of the microprocessor 31 through the resistor R4 when the press switch 19 is open (i.e., off).
Meanwhile, the hall sensor 7 is turned on by the magnetic field of the magnet 6 when the magnet 6, mounted at the end of the door 5, is adjacent to the hall sensor 7. Thus, the second switching transistor Q2 is turned on and the power voltage Vcc flows to the ground through a resistor R5 so that a low voltage level is applied to the third input port IN2 of the microprocessor 31.
On the contrary, when the magnet 6 is away from the hall sensor 7, (i.e., the door 5 is open), the hall sensor 7 is turned off and the second switching transistor Q2 is also turned off. As a result, the a high voltage level is applied to the third input port IN2 of the microprocessor 31.
FIG. 11 is a flow chart illustrating a dewatering control method of an automatic washing machine according to the present invention. FIG. 12 is a flow chart illustrating an unbalance sensing operation of a washing tub of FIG. 11.
The dewatering control method of the automatic washing machine according to the present invention will be described with reference to FIG. 11.
First, once the dewatering cycle progresses after washing and rinse of laundry, a variable state of the microprocessor 31 relating to the dewatering function is initiated.
Then, a level of an input signal input to the third input port IN2 of the microprocessor 31 is determined. Where the input signal is high, the dewatering cycle is stopped by according to whether the door 5 is open or not. At the same time, a progressing state of the indicating the progress portion indicative of the dewatering cycle in progress is stopped. Such steps repeat until a low signal is input to the third input port IN2 of the microprocessor 31. If the input signal is low, the dewatering cycle continues.
Subsequently, sensing time of the unbalance is counted from the starting time of the dewatering function to sense the unbalance of the washing tub for a certain time T1 since the dewatering function has progressed. The sensing time is then compared with a certain time T1. A sub-routine for sensing the unbalance of the washing tub is performed if the sensing time of the unbalance is less than time T1. The dewatering cycle ends by accumulatively counting the sensing time of the unbalance, storing it into a memory, and determining whether or not the end of the dewatering cycle, if not.
The sensing an unbalance of the washing tub according to the sub-routine will be described with reference to FIG. 12.
An effective time of the unbalance and the input number of times of the sensing signal are initiated respectively upon determining a normal dewatering cycle if the low signal is applied to the first input port IN0 of the microprocessor 31. Then, the step of accumulatively counting the sensing time of the unbalance returns. The input number of times of the sensing signal and the effective time of the unbalance are accumulatively counted until a certain number of times n of the sensing signal by counting the input number of times of the sensing signal if the input signal is high. Then, the step of accumulatively counting the sensing time of the unbalance returns after storing them into a memory of the microprocessor 31. The input number of times of the sensing signal responsive to the effective time is stored into the memory by counting the effective time of the unbalance from the initial input signal.
When a number of times that the unbalance sensing signal is input is as much as a certain number of times n, it is determined as the effective unbalance sensing signal. When the effective unbalance sensing signal from the initial unbalance sensing signal is input in a given time Δt, the unbalance of the washing tub is sensed. When the effective time of the unbalance is more than a given time Δt, the input number of times of the sensing signal and the effective time of the unbalance are initiated to determine an outer noise signal. Then, the step of accumulatively counting the sensing time of the unbalance returns.
That is, the unbalance of the washing tub is sensed in case where the input number of times n of the sensing signal is input to the microprocessor 31 in a given time Δt. Thereafter, the sub-routine for sensing the unbalance is performed as shown in FIG. 11. After performing the sub-routine, the unbalance of the washing tub is determined. When the washing tub is not unbalanced the sensing time of the unbalance is counted and stored into the memory. Then, the dewatering function continues until the end time of the dewatering cycle. When the washing tub is unbalanced, the indicative portion indicates the malfunction of the washing tub and at the same time the buzzer driving portion generates an alarm signal to stop the dewatering cycle.
The dewatering apparatus of the automatic washing machine and the control method thereof according to the present invention as aforementioned has the following effects.
First, since it is easy to exactly sense the unbalance of the washing tub and the opening of the door due to the dehydrating cycle when in the washing tub laundry leans to one side it allows a normal dewatering cycle to progress by controlling the respective portions to perform their own normal functions.
Second, it reduces manufacturing costs as well as the space required for mounting the dewatering apparatus according to simplification of the dewatering control apparatus. It also makes the washing machine compact overall.
Finally, efficiency and reliability of the washing machine can be improved by an exact control of the dewatering cycle.
It will be apparent to those skilled in the art that various modifications and variations can be made in the unbalance sensor and opening/closing sensor of the door according to the control method of the dewatering apparatus of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of the invention provided they come within the scope of the appended claims and their equivalents. | A dewatering apparatus of an automatic washing machine includes: an unbalance sensor mounted on a controller mounted into a top cover for sensing unbalance of a washing tub during a dewatering cycle; a magnet mounted on the washing machine door and a hall sensor mounted on the controller opposite to the magnet when the door is closed, for sensing whether the door is opened during the dewatering cycle. The unbalance sensor includes a casing in which a roller freely rolls, wherein a displacement (during unbalance of the washing tub) of the roller from a neutral position, is detected by, for example, a photo switch, press switch, or electrical switch, whereby a state of unbalance can be identified. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to the field of protective coatings to be used during coating operations of various surfaces including surfaces of vehicles or buildings. More specifically, in one embodiment the invention provides an improved method and composition for masking selected portions of a surface, in particular a vehicle surface, from paint. In another embodiment, this invention provides methods and compositions for protecting the walls and floors of a paint spray booth from paint overspray.
BACKGROUND OF THE INVENTION
[0002] It is well known that painting operations often require masking of certain portions of the surface of the painted object to prevent overspray. For example, it is often necessary to mask trim and windows on a vehicle (e.g. a motor vehicle) from paint overspray. Also, building stucco must frequently be protected from paint or primer coats. On occasion, it is necessary to mask painted portions of a vehicle or building from paints of a different color and overspray paints of the same color. In addition, it is often desired to protect the surfaces (e.g. floors or walls) of the area (e.g. paint spray booth) in which the over coating (e.g. painting) operation is performed.
[0003] In practice, masking operations are often one of the most time consuming and, therefore, expensive parts of the painting process. In spite of attempts to develop suitable chemical masks for vehicle painting, vehicle painters continue to use primarily masking tape and paper to cover portions of a vehicle where paint is not desired. To mask the trim on a car, for example, will often require many hours of tedious labor. Furthermore, even when done carefully, defects in such paint masks allow paint to contact surfaces that are desired to be protected.
[0004] Chemical masking solutions have been proposed to the problem of protecting surfaces during coating processing operations. However, such techniques have often not found extensive use. Some of the proposed chemical masks have been unsuitable for application to portions of a vehicle or building because of damage which would potentially occur to the protected portions of the vehicle or building. Other compositions are not water-soluble which increases the difficulty and expense of removal. In addition, masks that require solvents for removal are problematic in view of the increasing regulation of disposal of solvents as environmental regulation becomes stricter with time. Other compositions are difficult to apply, difficult to remove, excessively costly, or the like.
[0005] From the above it is seen that an improved masking that is easily applied and removed, that provides good surface protection, that is economical, and whose use entails little or no environmental impact is needed.
[0006] Woodhall et al. has disclosed various masking materials based on dextrin or polyvinyl alcohol. See U.S. Pat. Nos. 5,876,791; 5,362,786; 5,411,760; 5,523,117; 5,302,413 and 5,186,978. See also U.S. Pat. No. 5,550,182 to Ely which discloses a masking material comprising polyvinyl alcohol which is at least 98 % hydrolyzed. In addition, in U.S. Pat. Nos. 5,602,992 and 6,117,485 Woodhall et al. disclose masking materials based on dextrin or cellulose derivatives. Such masking materials may include acrylic emulsion polymers as thickeners, however, such emulsion polymers are reported to be alkali-swellable not water soluble.
SUMMARY OF THE INVENTION
[0007] The present invention provides a method of temporarily protecting a surface which comprises:
[0008] a) applying a continuous coating of a masking material to said surface, which masking material comprises, before drying an aqueous solution or emulsion consisting essentially of a film-forming, carboxylic acid-containing polymer;
[0009] b) coating all or a portion of said surface with a coating compound, said masking material preventing said coating compound from contacting said surface; and, thereafter
[0010] c) removing said masking material from said surface.
[0011] The carboxylic acid containing polymer is preferably the sole film-forming component of said solution or emulsion. More preferably said polymer is an acrylic acid or methacrylic acid-containing polymer, e.g. a water soluble acrylic acid or methacrylic acid-containing copolymer.
[0012] The method of the invention includes the steps of applying a substantially continuous film of a masking material on a vehicle (e.g. motor vehicle), building, floor, wall (e.g. spray booth floor wall or other spray booth surface) or other surface to be protected during a “coating operation” such as painting. The vehicle, building, or other surface may then be coated with a “coating compound” such as paint or any other compound which is to be applied to the surface. Finally, the masking material may be removed from the surface by washing with water thereby removing any coating compound that may be present on the masking material. These steps may be performed, for example, during an assembly line production of a vehicle or other article of manufacture.
[0013] By “coating operation” or “overcoating” it is desired to include any compound which is applied to a surface. Coating compounds include materials such as paint or other finishing materials such as lacquer, varnish, waxes and the like which adhere to the surface to which they are applied thereby forming a relatively permanent finish. Coating compounds, however, may also include compounds designed for temporary application to surfaces as in surface preparative treatments such as acids, oils, and antioxidants from which it may be necessary or desired to shield other surfaces.
[0014] By “building” it is intended to mean herein a house, warehouse, apartment, garage, store, or the like. By “vehicle” it is intended to mean herein a car, boat, plane, train, railroad car, or the like. By “substantially continuous film” it is intended to mean herein a film lacking pinholes through which paint or other materials generated during a coating operation processing could reach an underlying surface.
[0015] The masking material is, in one embodiment, a composition comprising an aqueous solution consisting essentially of a film-forming acrylic or methacrylic acid copolymer and sufficient alkali to neutralize and solubilize said copolymer in water. The masking materials preferably contain a high concentration of solids. In a particularly preferred embodiment the acrylic or methacrylic acid copolymer may comprise from about 1 percent to about 50 or 60 percent, more preferably from about 1 percent to about 50 percent and most preferably about 2 percent to about 20 percent, e.g. 2 to about 15 percent by weight, of the aqueous solution. A particularly preferred embodiment comprises about 2 to 10 percent, by weight acrylic acid copolymer.
[0016] The masking material may additionally include a surfactant. The surfactant may comprise up to about 0.1 weight percent fluorinated surfactant. The surfactant, when present, ranges up to about 5 percent, more preferably up to about 2 percent, and most preferably up to about 1 percent, by weight, of the masking composition. The surfactant may include a foam reduction or foam control agent.
[0017] The composition is formulated as an aqueous composition and thus, the remainder of the composition is preferably made up of water. Thus, water may range up to about 98 percent, more preferably up to about 95 percent, by weight, of the composition.
[0018] A particularly preferred composition for use in the method of this invention comprises 5%, by weight, of an acrylic or methacrylic acid copolymer and 92 to 94% deionized water. A water soluble alkali, e.g. sodium hydroxide, is added in an amount sufficient to neutralize and solubilize said acrylic or methacrylic acid copolymer, e.g. the pH of the composition may be 7.1 to 7.2 Ethylenediaminetetraaceticacid as an aqueous 0.9% solution, by weight, is added to control spray viscosity, wetting and chelating properties. The final viscosity of the composition is adjusted to 1400-1700 c.p.s. as measured at 25° C., with a Brookfield LFV Viscometer for optimum spray viscosity.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention provides an improved method and composition for protecting a vehicle (e.g. motor vehicle) or other surface subject to a coating operation such as painting. For example, certain regions of an automobile, or other surface, may be masked using the coating composition of the present invention to protect those regions from paint overspray in a painting booth.
[0020] In addition it is also often desired to protect the surfaces of the area in which an overcoating operation (e.g. painting) is performed. In particular, it is desired to protect the walls, floors and other surfaces of such an area (e.g. a painting booth) from paint overspray and spills. In addition, it is also desirable to reduce airborne dust in such areas during overcoating operations.
[0021] This invention provides compositions and methods to meet these needs. The methods entail coating the surface to be protected (e.g. surface of a car or truck or the walls and/or floors of a spray booth) with a temporary protective coating composition. One or more coating (e.g. painting) operations are performed and, when desired, the protective composition is removed.
[0022] The coating compositions of this invention, when applied to a surface (e.g. the surface of an automobile), produce a substantially continuous film that adheres well to the underlying surface. By “substantially continuous film” it is intended to mean herein a film generally lacking pinholes through which water, oil, paint, dust, or the materials could reach the underlying surface. Further, the material can be removed easily from the surface to be protected after use with a water wash, or by mechanical means such as scraping or peeling, or by combinations of these methods. In addition, because the material is fully biodegradable, it may be simply disposed of (e.g., washed down a sewer) with no substantial environmental impact.
[0023] A preferred method of protecting surfaces according to this invention includes steps of applying the coating compositions to the surface to be protected in a substantially continuous film. The compositions are then dried to form a coating that protects the underlying surface from the coating operation (e.g. paint overspray). The coating may be subsequently removed from the surface by simply washing with water when it is no longer required. In a particularly preferred embodiment, the coatings of the present invention are used to protect components of motor vehicles (e.g. automobiles or automobile finishes), and the walls and floors of spray booths or other areas or structures that may be contacted with overspray in a coating (e.g. painting) operation.
[0024] A carboxylic acid-containing, polymer, e.g. an acrylic or methacrylic acid-containing copolymer is utilized in the films of the present invention to provide solids and to build film thickness. It was an unexpected discovery of the present invention, that the use of acrylic or methacrylic acid copolymers, alone, provides masking compositions that show exceptional coating, film forming, and drying properties. In particular, the use of high concentrations of the copolymer allow the buildup of a thick coating which nevertheless shows relatively low viscosity, good coating properties and an extremely rapid drying time.
[0025] Preferably, the acrylic or methacrylic acid-containing copolymer will comprise sufficient acrylic or methacrylic acid and have a molecular weight sufficient to enable the copolymer to impart the necessary viscosity to the aqueous emulsion or solution that is used in the method of the invention. Also, preferably the acrylic or methacrylic acid-containing copolymer will form a cohesive film at room temperature, i.e. it will have a Tg of less than about 25° C. Finally, it is preferred that the acrylic or methacrylic acid-containing copolymer will contain sufficient acrylic or methacrylic acid to be solubilized by alkali in an aqueous solution. To achieve these objectives an acrylic acid or methacrylic acid monomer may be copolymerized with other acrylate monomers, e.g. ethylacrylate, butylacrylate, octylacrylate and the like. An example of suitable copolymer includes a copolymer of methacrylic acid and ethylacrylate.
[0026] The quantity and type of the acrylic or methacrylic acid copolymer in the coating composition may be optimized for a particular application. This is accomplished empirically. Generally where it is desired that the composition dry to provide a thicker final coating more solids are added to the composition. However, the upper limits to the acrylic or methacrylic acid copolymer concentration are dictated by the resulting viscosity of the composition. The viscosity of the wet coating must be low enough to permit application to and continuous coating of the surface. Thus, in order to produce a thick coating one increases the solids concentration, but not beyond a point where the composition becomes difficult or impossible, to apply. Conversely, where a thin coating is desired, the solids composition may be decreased, but not to a point where the composition fails to form a continuous protective coating when dried.
[0027] To some extent, the optimal solids content of the mixture is a function of the application method. It is expected that the composition may be applied by a variety of methods known to those of skill in the art. These methods include, but are not limited to painting, dipping, spraying, reverse roller coating, and the use of doctor bars. One of skill in the art will appreciate that application by spraying will generally require a composition of lower viscosity than application by the use of doctor bars. Thus a composition intended for application by spraying may contain a lower solids concentration than a composition applied by dipping or doctoring.
[0028] The coatings of the present invention may additionally contain a surfactant. For example, the masking composition may include nonionic alkyl aryl surfactants such as Triton CF-10 and CF-12 (Rohm & Haas, Philadelphia, Pa., U.S.A.). Also suitable is Triton X-100 and surfactants having fluorinated alkyl chains such as “Flourad” products sold by Minnesota Mining and Manufacturing (St. Paul, Minn., U.S.A.) and “Zonyl” products sold by DuPont Company (Wilmington, Del., U.S.A.). In addition, many embodiments include polyethoxy adducts or modified (poly)ethoxylates such as Triton DF-12 and DF-16 sold by Union Carbide (Danbury, Conn., U.S.A.). Other surfactants include nonylphenoxypolyethanol (such as IGEPAL CO-660 made by GAF), polyoxyalkylene glycol (such as Macol 18 and 19 made by Mazer Chemicals), acetylenic diol-based surfactants (such as Surfynol 104A made by Air Products), and the like.
[0029] To provide a continuous and level film, the masking composition should adequately wet the surface to be protected. However, many surfaces, in particular, car body finishes, are themselves highly hydrophobic or purposely treated (e.g. waxed) to have a low surface free energy so that water will bead. To facilitate wetting and thereby prevent the masking composition from beading, the surface tension of the masking composition may be lowered by the addition of a surfactant, e.g. a fluorinated surfactant.
[0030] One advantage of the compositions utilized in the method of the present invention, as compared to the dextrin or cellulosic film formers of Woodhall et al. is that thickeners and/or preservatives are not required. Because acrylic acid copolymers do not support the growth of microbes, fungi and the like, at pH below 7 no preservative is required. Moreover, since the acrylic acid or methacrylic acid copolymer, itself, is a thickening agent as well as the film forming component of the masking material no additional thickening agent is required.
[0031] Preferred embodiments of the compositions of this invention may also include components to adjust pH. Means of adjusting pH are well known to those of skill in the art. In particular, where the composition is to be used as a masking composition on an automotive finish, it is often desirable to adjust the composition to a pH of 6 to about 7. This may be accomplished by the addition of one of a number of water soluble bases well known to those of skill in the art. These include, but are not limited to sodium hydroxide, sodium bicarbonate and amine bases such as pyridine and ethylamine and ammonia.
[0032] The mask composition is an aqueous solution and therefore includes a substantial amount of water before drying. A variety of the materials may also be included in the coatings to confer specific additional properties. Thus, for example, the coating compositions may additionally include dyes or colorants, antioxidants or corrosion inhibitors, ultra-violet inhibitors, rust inhibitors and the like. Preferred embodiments may include foam reduction or foam control agents such as FoamMaker™, Bubble Breaker™, and 1 and 2 octanol. Antistatic compounds (preferably water soluble antistatics such as Larostat 264A made by Mazer Chemicals) may be added to prevent dust from being drawn to the surface. The mask composition may also include sequesterants (typically less than 1%).
[0033] The coating solutions are made by conventional means which typically comprise mixing the components of the masking material at substantially atmospheric pressure, so as to form a homogeneous solution. Heat may be applied to speed preparation of the coating solution. After formation of the homogeneous solution, the pH may be adjusted as discussed above. In a particularly preferred embodiment, the pH is adjusted to pH 7-9 by the addition of sodium hydroxide or other pH adjusting reagents.
[0034] The coating compositions are conveniently formulated as aqueous (water-based) solutions or emulsions. The aqueous formulation generally lacks toxic solvents and is therefore relatively easy to handle and work with and is readily disposed of without adverse environmental impact. Thus, it is generally desirable to avoid the inclusion of any reagents (e.g. oil, organic solvents, etc.) that impose difficulties in handling and/or disposal. Preferred coating compositions are therefore aqueous compositions substantially or completely oil free and free of organic solvents.
[0035] The coating (masking) material is applied by one of a variety of techniques known to those of skill in the art. These include painting, dipping, spraying, reverse roller coating, and the use of doctor bars. Particularly preferred techniques include brushing and spraying of the material. In one preferred embodiment the surface to be protected is blown dry of dust and debris. In some cases, additional water may be added for easier application, such as a 10% dilution. Thereafter, the masking material is applied with a pressure pot sprayer, preferably first in a thin mist and, thereafter, in a flow coat or thicker substantially continuous film. For some applications, the mist coat will not be necessary. The mask material is sprayed primarily in the surface to be protected, although overspray will not pose significant problems since any overspray may be readily removed with, for example, a wet towel or sponge.
[0036] In preferred embodiments, the resulting masking coating is applied in a wet coating in a thickness ranging from about 1 to about 10 mils, more preferably ranging from about 1 to about 4 mils, and most preferably ranging from about 1 to about 2 mils. This wet coating then dries to form a continuous dry coating ranging from about 0.5 to about 1 mil in thickness.
[0037] The masking material is typically permitted to dry at atmospheric temperatures and pressures. For a 1 to 2 mil wet thickness coating, such drying will take about 10 minutes at 70° F. and about 50% humidity.
[0038] Alternatively, the masking composition may be force-dried. Force drying may be accomplished by means well known to those of skill in the art. These include, but are not limited to the application of heat (e.g. radiant heating, oven baking, or hot air blowers), the reduction of air humidity, air movement or any combination of these means. Under forced drying conditions at about 150° F. and about 50% humidity, the same coatings will dry in about 2 minutes.
[0039] After drying of the masking composition, the remaining unprotected surface is then painted or otherwise coated without fear of overspray on the portions of the surface protected by the masking material. If the processing operation includes painting, the paint applied to the surface and allowed to thoroughly dry. Such drying times will vary radically depending upon the particular type of paint utilized.
[0040] After drying of the paint, the masking material is removed from the protected surface. Such removal operations may include, for example, peeling or scraping of the material off of the protected surface. However, it is most preferred that the masking composition be removed by normal washing with water. Pressure washing with water may be desired in some instances. The material will be removed readily since it is easily miscible or soluble in water.
[0041] One of skill in the art will readily appreciate that the steps of applying and drying the masking composition, applying and drying the paint or other subsequent coating, and removing the masking coating may be easily set up for mass production, as in an assembly line.
EXAMPLE
[0042] The following example is intended to illustrate the present invention and are not intended to limit the scope of the invention in any way.
EXAMPLE
[0043] 5 parts, by weight, of a 28%, by weight acrylic emulsion comprising a copolymer of methacrylic acid and ethylacrylate are diluted with 93.8 parts water, 0.3 parts of a 50% NaOh and 0.9 parts of a 39% solution of ethylenediamine tetra acetic acid in water to provide an aqueous solution of a masking material having a viscosity of 1400 to 1700 c.p.s.
[0044] The coating is applied, by spraying, to an automotive body panel test surface thereby masking a portion of the test surface. The coatings is then either air dried or force-dried by heating.
[0045] The masked test panel is then sprayed with an automotive body paint and allowed to dry. The coating compositions are then removed from the masked portion of the panel by simply washing the panel with water.
[0046] The coating generally provide uniform wetting of the test surface. The coating dries rapidly, typically a 1 mil layer drying in about 21 minutes at ambient temperature (approximately 60° F. and 50% humidity).
[0047] The coating is easily removed by the application of pressurized water and the masked regions show little or no penetration by the paint.
[0048] The above description is illustrated and not restrictive. Many variations of the invention will be apparent to those of skill in the art upon review of this disclosure. Merely by way of example, while the invention is illustrated with regard to particular brands of materials used in the mask, the invention is not so limited. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents.
[0049] It is understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims. All publications, patents, and patent applications cited herein are hereby incorporated by reference in their entirety for all purposes. | The present invention provides a method of temporarily protecting a surface which includes the steps of applying a continuous coating of a masking material to said surface, which masking material comprises, before drying, an aqueous solution or emulsion consisting essentially of a film-forming, carboxylic acid-containing polymer; coating all or a portion of said surface with a coating compound, said masking material preventing said coating compound from contacting said surface; and, thereafter, removing said masking material from said surface. Preferably said carboxylic acid-containing polymer is an acrylic or methacrylic acid-containing copolymer and is the sole film-forming component of the aqueous solution or emulsion. | 2 |
RELATED APPLICATION
[0001] The present application claims priority of India Patent Application No. 2598/Del/2004 filed Dec. 30, 2004, which is incorporated herein in its entirety by this referenced.
FIELD OF THE INVENTION
[0002] The invention relates to a memory device with reduced leakage current.
BACKGROUND OF THE INVENTION
[0003] The impact of the subthreshold leakage current on the circuit performance should be considered seriously as device dimension have scaled down to deep submicron level in CMOS technology. This is a significant problem in memory structures using precharging circuitry which frequently require discharging of the bitlines to allow bit sensing in memories.
[0004] FIG. 1 illustrates the schematic diagram for a conventional memory cell that operates as a single storage unit in a larger memory structure. One problem with such memory cells is the leakage current through multiple read transistors 30 coupled to a shared bitline 14 which can result in erroneous read operation. Increased leakage current severely affects the performance of the memory circuits (e.g., register files). Further, the problem is increased by noise on the read signal line due to coupling noise.
[0005] One way to reduce the leakage current is utilization of high threshold voltage (V T ) devices. However, such devices exhibit reduced performance in terms of device speed and area. In addition, manufacturing costs are increased in high V T devices due to the additional silicon layers required in such devices.
[0006] To overcome this problem, FIG. 2 illustrates memory circuits according to U.S. Pat. No. 6,320,795. The patent discloses a register file cell 40 which is capable of reducing leakage current and is less likely to require a larger keeper transistor 26 to prevent erroneous reads. Memory cell 40 includes a pull-down transistor (MPD) 42 , a static logic gate 44 , and a storage cell 46 . Pull-down transistor 42 is operative for discharging the bitline 14 to the ground 36 when a predetermined control indication is received at the input terminal thereof from the logic gate 44 . In this embodiment, an N-channel IGFET device is used as the pull-down transistor 42 and therefore, the predetermined control indication is a logic high value applied to the gate terminal of pull-down transistor 42 .
[0007] Logic gate 44 acts to buffer the input of the pull-down transistor 42 from the noise commonly associated with the read signal. Logic gate 44 includes two input terminals 48 and 50 .
[0008] When the read signal is logic low and the data stored in the register file cell is logic high, logic gate 44 (NOR gate) outputs a logic high value to the gate terminal of pull-down transistor 42 . As a result, pull-down transistor 42 discharges bitline 42 to ground 36 . When stored data value in cell is logic low and when the read signal is logic low, the output of logic gate 44 is logic low which results in pull-down transistor 42 to be turned off and hence, bitline 14 is not discharged. The output of the logic gate 44 is logic low when the active low read signal is logic high, regardless of the data bit value stored in cell 46 .
[0009] Thus the goal is to isolate pull-down transistor 42 from the read noise associated with the read signal. Although the application of a static logic gate helps to reduce such leakage current to a significant level in such circuits, this approach is effective for reducing the leakage currents generated only due to the noise voltages on the input terminal of pull-down transistor 42 . The technique does not have significant impact on the leakage currents typically associated with low V T scaled devices.
[0010] FIG. 3 shows a schematic diagram illustrating a register file cell 60 with another embodiment. Memory cell 60 includes a pull-down transistor 62 (MPD), logic gate 64 , a storage cell 66 , a bias device 72 and a read transistor 74 (MREAD). Logic gate 64 of memory cell 60 provides isolation between a possibly noisy read signal and the input terminal of pull-down transistor 62 , in the same way as in previous case. In addition, bias device 72 is operative for applying a bias voltage to pull-down transistor 62 during appropriate periods and thereby reduces the level of the current leakage through the device during those periods. Thus memory cell 60 can be implemented using low V T transistors to achieve high performance operation while still maintaining high robustness.
[0011] When the read signal is logic high, a read transistor 74 couples the second output terminal of pull-down transistor 62 to ground 36 . Therefore a logic low voltage is present at the second input 70 of logic gate 64 . During a read operation, the output of logic gate 64 is logic high when the data bit stored within cell 66 is logic low. Under this condition, pull-down transistor 62 is turned on and bitline 14 is discharged to the ground 36 through read transistor 74 . When the data bit stored within cell 66 is logic high, the output of logic gate 64 is low and pull-down transistor 62 remains off.
[0012] When the read signal is logic high (i. e., a read operation is being performed for cell 60 ), bias device 72 (P-channel IGFET) is off and has substantially no effect on the circuit. When the read signal is logic low (i. e., a read operation is not being performed for cell 60 ), bias device 72 couples the supply terminal 18 to the second output terminal of pull-down transistor 62 . This places a logic high voltage on the second input 70 of logic gate 64 , which forces the output of the logic gate to a logic low value. Therefore a negative voltage exists from the input terminal of pull-down transistor 62 to the second output terminal of pull-down transistor 62 . As transistor 62 is an N-channel IGFET device, the negative voltage from the input terminal (the gate) of pull-down transistor 62 to the second output terminal ( the source) of pull-down transistor 62 reduces the leakage current through pull-down transistor 62 to negligible levels. When the read signal again switches to a logic high value, the bias voltage is removed from pull-down transistor 62 and a read operation takes place.
[0013] As described in the prior art, such an embodiment is capable of reducing leakage current through pull-down transistor 62 due to the effect of read noise associated with read signal on the input of pull-down transistor 62 . This helps to reduce the leakage level through pull-down transistor 62 due to generation of a negative voltage from the input terminal (i.e., the gate terminal) of pull-down transistor 62 to the second output terminal (i. e., the source terminal) of pull-down transistor 62 .
[0014] The drawback of such an arrangement is its inability to check the leakage current through pull-down transistor 74 . Also the presence of bias transistor X raises the potential of intermediate node 80 near to supply voltage whenever read signal is low (i. e., when a read operation is not being performed). This technique appears to be unable to reduce the leakage current to the same order at a very low potential of intermediate node. In such memory circuit arrangement, significant leakage current is produced because of low V T pull-down devices 107 and 117 used to maintain high performance. Hence, the goal of the bias device is to reduce leakage through pull-down transistor 62 during some or all of the non-read period associated with a register file cell.
SUMMARY OF THE INVENTION
[0015] To obviate the aforesaid drawbacks the object of the instant invention is to provide a memory device with reduced leakage current.
[0016] Another object of the instant invention is to lower down the leakage current through pull-down low threshold voltage (V T ) semiconductor device.
[0017] Another object of the instant invention is to provide memory cells using submicron technology with improved performance characteristics in speed, area and cost.
[0018] A memory device of the present invention having reduced leakage current includes at least one bitline and a plurality of memory cells, with each memory cell passing at least one output of a storage cell and each output coupled to each bitline through read access circuitry. The read access circuitry includes a logic device responsive to data value stored in the storage cells and a read signal for generating a control output, a first switching device having its control terminal coupled to the control output of the logic device and its first terminal coupled to the bitline, a second switching device with its control terminal coupled to the control output of the logic device for passing a low voltage to a common terminal of said first and said second switching devices, and a third switching device for passing a node reference voltage to the common terminal which is responsive to the control output of the logic device.
[0019] Preferably, the node reference voltage for the third switching device in all memory cells is passed from a common reference voltage generator. In a preferred embodiment, the common reference voltage generator includes a plurality of diode-connected transistors connected in series, with one end of the series coupled to a high voltage source and other end of the series coupled to the output of the common reference voltage generator.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[0020] FIG. 1 illustrates a commonly used memory circuit.
[0021] FIGS. 2 and 3 show embodiments of U.S. Pat. No. 6,320,795.
[0022] FIG. 4 shows a circuit in accordance with the invention.
[0023] FIG. 5 illustrates another embodiment of the present invention.
[0024] FIG. 6 show the simulation results.
DETAILED DESCRIPTION
[0025] FIG. 4 illustrates a memory cell according to one of the embodiments of the instant invention. A memory cell 100 comprises a storage cell 101 , a static logic gate 102 , a reference voltage generator circuit 104 , pull-down transistors 107 and 117 , and a bias transistor MBIAS 115 . A pull-down transistor 107 is coupled to bitline 108 for conditionally discharging the precharged bitline 108 during a read operation based on a data stored in storage cell 101 . Static logic gate 102 , which is a NOR gate in the present embodiment, drives pull-down transistor 107 depending upon the Read signal and data stored in cell 101 . It also act as a buffer between possibly noisy read signal and the input terminal of pull-down transistor 107 . In present embodiment a reference voltage generator circuit 104 along with a bias transistor MBIAS(P-channel MOSFET) is used for significant reduction of bitline 108 leakage through ground 113 .
[0026] When the read signal is logic low (i. e., a read operation is to be performed) and data stored in bit cell 101 is also logic low, output of the static logic gate 102 is logic high. This turns on pull-down transistors 107 and 117 resulting in discharging of bitline 108 through the ground 113 . Under this condition a logic high is present at the gate terminal 116 of bias transistor MBIAS and hence turning it off. Therefore no effect of reference voltage generator 104 is seen at node 118 of the circuit. For the opposite case when read signal is logic high, the output of the static logic gate 102 is logic low regardless of data bit value stored in cell 101 . As the output of the static logic gate 102 is connected to gate terminal of the both pull-down transistors 107 and 117 , both pull-down devices are off and therefore bitline 108 is decoupled from the ground 113 .
[0027] When the read signal is high (i. e., no read operation is being performed) a low logic value at the output of the static logic gate 102 , turns on the bias transistor MBIAS. Therefore the voltage reference generator circuit 104 raises the potential level of the intermediate node 118 just above the threshold voltage (depending on the nature of the reference voltage generator circuit) of pull-down devices 107 and 117 . The leakage current through pull-down transistor 107 approaches a lower level as the potential at intermediate node 118 is just above the threshold voltage of the pull-down device. Also, as intermediate node 118 is charged to a lower potential (just above the V T of pull-down device), unlike to the supply level in U.S. Pat. No. 6,320,795, hence circuit performance is improved due to reduction in charging/discharging time.
[0028] FIG. 5 illustrates a simplest embodiment of the voltage reference generator of the present invention. According to this embodiment, diode connected transistors 51 and 52 are connected in series to high voltage supply 109 to produce voltage drop and produce desired voltage at the output. The goal behind the adding of a voltage reference generator circuit is to provide a lower voltage just above V T of pull-down device to the intermediate node 118 . The area overhead due to the addition of the circuit 104 is negligible because the reference voltage generator circuit 104 is shared among a number of memory cell circuit 100 .
[0029] FIG. 6 illustrates that the goal of lowering down the leakage current through pull-down device 107 is achieved at a very low potential Oust above the V T of pull-down device) of intermediate node 118 , in comparison to a significantly high potential (near to supply) of U.S. Pat. No. 6,320,795. As the intermediate node 118 potential reaches below the V T of pull-down device, the bit-Line leakage current increases abruptly. Hence, the best case scenario is when the intermediate node potential is just above the V T of the pull-down device 107 .
[0030] Table 1, shows the simulation results for the set-up of the prior art as shown in FIG. 2 .
[0031] Simulation results for the set-up of the present invention shown in FIG. 4 are given in Table 2. Simulation is performed under the following conditions: Pull-down devices 107 and 117 are 4 microns in size. The size of static logic gate 102 and keeper device 110 are kept to a minimum and the load of the bitline 108 is taken as 100 fF.
[0032] Table 2 shows the variation in leakage current with potential at intermediate node 118 . Bitline 108 is pulled down only when both read enable and data value stored in cell 101 are logic low.
[0033] As the intermediate node potential approaches above V T of the pull-down device, the total leakage current reduces significantly. Simulation result shows ˜57% reduction in total leakage current at node potential 305 mv in comparison to the prior art.
TABLE 2 PRIOR ART SIMULATIONS. READ BIT-LINE PMOS TOTAL DATA ENABLE LEAKAGE LEAKAGE LEAKAGE LOGIC HIGH LOGIC 1E−12 7.89E−09 7.891E−09 LOW LOGIC HIGH LOGIC 7.89E−09 0.5E−09 8.39E−09 HIGH PRESENT INVENTION SIMULATIONS NODE BIT-LINE Vref. Gen. POTENTIAL LEAKAGE LEAKAGE TOTAL LEAKAGE 778 mv 1.22E−12 6.15E−09 6.151E−09 545 mv 1.45E−12 4.65E−09 4.651E−09 *305 mv 1.87E−12 3.36E−09 3.361E−09 126 mv 0.1E−09 2.40E−09 2.5E−09
[0034] Although the present invention is described in reference to register file memories with a single bitline, it can applied to all types of memories in CMOS ICs requiring precharge/discharge mechanism. According to yet another embodiment, the circuitry can be extended to memories with multiple bitline for memories producing stored data value and its complementary value. According to yet another embodiment, the logic gates or transistor used in the embodiment may be changed for the memory to be in active phase for high read signal. Those of ordinary skill in the art will appreciate that various combinations and arrangements may be employed without departing from the scope of the invention
[0035] It is believed that the present invention and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an exemplary embodiment thereof, it is the intention of the following claims to encompass and include such changes. | A technique for reducing the bitline leakage current while maintaining a level of performance characteristics of low threshold voltage transistors in deep submicron CMOS technology incorporates a reference voltage generator circuit in combination with bias transistor MBIAS. The output of a static logic gate is connected to the input terminal of the pull-down devices. The reduction in leakage current through pull-down devices whenever a read operation is not performed contributes to a significant reduction in overall leakage current in the circuit. | 6 |
FIELD OF THE INVENTION
The present invention relates to a method and apparatus to lower and fold fabric continuously and particularly to a method and apparatus to mechanically lower and fold fabric concurrently at the same amount knitted by a circular knitting machine.
BACKGROUND OF THE INVENTION
Conventional fabric folding machines adopted for use with circular knitting machines now on the market can be divided into half-width fabric folding machines and full-width fabric folding machines according to the fabric folding width. On a full-width fabric folding machine, the fabric folding machine is located in a circular knitting machine which continuously knits and produce fabric, the fabric folding machine concurrently folds the lowering fabric at a maximum width. On the other hand a half-width fabric folding machine folds the fabric at a width one half of the full-width fabric folding machine.
The half-width fabric folding machine has drawbacks in use. After the fabric is knitted by the circular knitting machine, it has to be treated in a dyeing process. A dyeing tank usually can hold a fixed amount of fabric in the dyeing process. The fabric has a head and a tail that are connected to reach the fixed amount of quantity before being loaded into the dyeing tank to do dyeing process. Due to the half-width fabric folding machine provides a batch of fabric only one half of the full-width fabric folding machine, after the dyeing process is finished the head and tail portions of the fabric that are not evenly dyed have to be cut off. This results in a greater amount of waste. Reducing the waste can reduce the material cost. Hence the main stream of the market of the fabric folding machine for circular knitting machines is the full-width fabric folding machine that can fold the fabric at the maximum full-width.
However, the conventional full-width fabric folding machine still has its share of problems. Refer to FIGS. 1A and 1B for the conventional fabric folding machine in operating conditions. As shown in FIG. 1A , when a circular knitting machine continuously knits a fabric 7 , if the fabric 7 does not sag naturally below a fabric spreading roller set 2 and above a fabric folding bar set 5 , the fabric below the fabric folding bar set 5 increases gradually at the same amount knitted continuously by the circular knitting machine. If the driving wheel 3 rotates continuously clockwise to drive a chain 4 to move the fabric folding bar set 5 horizontally rightwards, the fabric folding bar set 5 flatly spreads the increased fabric 7 beneath thereof on a fabric loading board 6 same as the mount knitted by the circular knitting machine. If the driving wheel 3 continuously rotates clockwise to drive the conveying chain 4 to move the fabric folding bar set 5 horizontally rightwards, the fabric folding bar set 5 can flatly spread the increased fabric beneath thereof same as that knitted continuously by the circular knitting machine on the fabric loading board 6 . However, after the fabric folding bar set 5 has moved horizontally rightwards, the fabric 7 below the fabric spreading roller set 2 and above the fabric folding bar set 5 has two problematic conditions, first the fabric folding bar set 5 has to be incorporated with an automatic faster fabric conveying means (such as a programmable controlled motor to generate faster rotation) to deliver the fabric faster below the fabric folding bar set 5 . But such an approach often creates another problem as shown in FIG. 1B in which the fabric 7 laid on the fabric spreading board is creased. On the other hand, if the fabric folding bar set 5 does not automatically convey the fabric faster, the fabric originally hung below the fabric spreading roller set 2 and above the fabric folding bar set 5 sags as shown in FIG. 1B . When the fabric folding bar set 5 moves horizontally the sagged fabric hinders its movement and could cause machine jam. To overcome the problems shown in FIG. 1B , a preferable approach is to move the fabric folding bar set 5 rapidly beneath the fabric spreading roller set 2 where the fabric 7 is delivered before it is knitted by the circular knitting machine, and the fabric 7 which is originally located below the fabric spreading roller set 2 and above the fabric folding bar set 5 also has to be conveyed at the same time beneath the fabric folding bar set 5 to be flatly spread on the fabric loading board 6 . Then machine jam can be prevented when the fabric folding bar set 5 moves horizontally. While the aforesaid approach seems advisable in principle, in practice no physical technique is yet available to move the fabric folding bar set 5 rapidly beneath the fabric 7 delivered by the fabric spreading roller set 2 before the circular knitting machine actually knits the fabric 7 .
In short, the conventional half-width and full-width fabric folding machines still have problems in practice, notably:
1. The half-width fabric folding machine provides fabric only one half of the full-width fabric folding machine. After the dyeing process the head and tail ends of the fabric 7 have to be cut off that creates a lot of scraps. Waste of manpower and material occurs.
2. The conventional full-width fabric folding machine cannot flatly spread the fabric without generating creases during the return movement of fabric folding. The creases are difficult to flatten after being compressed by the weight of the fabric laid on the upper side.
3. During the return movement of fabric folding of the conventional full-width fabric folding machine the fabric above the fabric folding bar set 5 easily sags before lowering and folding due to inadequate tension of the transverse fabric 7 . This hinders the horizontal return path of the fabric folding bar set 5 and could cause machine jam.
All the problems mentioned above related to the half-width and full-width fabric folding machines are still existed in the industry pending to be resolved.
SUMMARY OF THE INVENTION
The primary object of the present invention is to solve the aforesaid problems of the conventional half-width and full-width fabric folding machines and the fabric folding methods thereof by providing a method and apparatus to increase tension to maintain flat of the transverse fabric before fabric lowering and move the transverse fabric mechanically in a repetitive transient storing and feeding approach so that the fabric is lowered and folded in full-width at an amount same as knitted and unloaded by a circular knitting machine.
To achieve the foregoing object the present invention provides a method and apparatus to lower and fold fabric at an amount same as knitted and unloaded by a circular knitting machine. The method includes: providing a fabric spreading roller set in a circular knitting machine below fabric knitted continuously by the circular knitting machine that rotates synchronously with a needle cylinder of the circular knitting machine in the same direction and has spinning power to move the fabric downwards; winding the fabric knitted continuously by the circular knitting machine through the fabric spreading roller set to flatten the fabric and winding out from the fabric spreading roller set at one side; providing two horizontal fabric folding rails below the fabric spreading roller set perpendicular thereof that have respectively a horizontal track; providing a first fabric extending bar at the fabric winding out side of the fabric spreading roller set that is hinged on an outer side of the track in a straddle manner in parallel with the fabric spreading roller set; winding the fabric delivered from the fabric spreading roller set on the first fabric extending bar which winds out the fabric at a lower side in a direction opposite to the winding in direction; providing a tension balance moving bar on the track in a straddle manner at the fabric winding out side of the first fabric extending bar that is parallel with the fabric spreading roller set and movable horizontally and reciprocally on the track; winding the fabric released from the first fabric extending bar on the tension balance moving bar and winding out the fabric at a lower side thereof opposite to the winding in direction so that the first fabric extending bar and the tension balance moving bar are spaced from each other at a distance of a first zone fabric length; providing a first chain holding spot fastened to another outer side of track of the fabric folding rail at one side same as the fabric winding out side of the first fabric extending bar; providing a chain with one end held on the first chain holding spot and another end winding on a side end of the tension balance moving bar and winding out at a lower side in a direction opposite to the winding in direction so that the first chain holding spot and the tension balance moving bar are spaced from each other to form a first zone chain length; providing a second fabric extending bar at the fabric winding out side of the tension balance moving bar that is hinged on the outer side of the track in a straddle manner parallel with the fabric spreading roller set; winding the fabric released from the tension balance moving bar on the second fabric extending bar and winding out the fabric at a lower side opposite to the winding in direction so that the tension balance moving bar and the second fabric extending bar are spaced from each other at a second zone fabric length; providing a chain turning axle hinged on the outer side of the track at the chain winding out side of the tension balance moving bar; winding the chain released from the tension balance moving bar on the chain turning axle and winding out at a lower side opposite to the winding in direction so that the tension balance moving bar and the chain turning axle are spaced from each other at a second zone chain length; providing a fabric level moving and lowering means on the track that is movable reciprocally and horizontally and hinged by a forward turning fabric folding bar and a reverse turning fabric folding bar in a straddle manner that are parallel with each other and parallel with the fabric spreading roller set and movable reciprocally and horizontally on the fabric folding rails between the second fabric extending bar and the chain turning axle and have spinning power; winding the fabric released from the second fabric extending bar between the forward turning fabric folding bar and the reverse turning fabric folding bar and lowering the fabric below and between the forward turning fabric folding bar and the reverse turning fabric folding bar at an amount same as the continuously knitted amount of the circular knitting machine and the second fabric extending bar being spaced from the interval of the forward turning fabric folding bar and the reverse turning fabric folding bar to form a third zone fabric length; providing a second chain holding spot on the fabric level moving and lowering means; fastening the chain winding out from the chain turning axle to the second chain holding spot so that the chain turning axle and the second chain holding spot are spaced from each other at a third zone chain length; providing a fabric loading board in the circular knitting machine below the fabric level moving and lowering means at a width at least same as the fabric width and at a length at least same as the reciprocal moving distance of the forward turning fabric folding bar and the reverse turning fabric folding bar while the fabric level moving and lowering means is moving horizontally and reciprocally, and the fabric loading board and the fabric spreading roller set rotating synchronously in the same direction; moving the fabric level moving and lowering means horizontally and reciprocally between the second fabric extending bar and the chain turning axle while the fabric is delivered and lowered below the interval of the forward turning fabric folding bar and the reverse turning fabric folding bar at the same amount knitted continuously by the circular knitting machine, the fabric decreasing an amount at the third zone fabric length equal to the sum of fabric increasing amount of the first zone fabric length and the second zone fabric length, and the fabric increasing same amount at the first zone fabric length and at the second zone fabric length, and the fabric decreasing an amount at the third zone fabric length equal to an increasing amount of the third zone chain length, and also equal to the sum decreasing amount of the first and second zones chain length; on the other hand, the fabric also increasing an amount at the third zone fabric length equal to the sum of fabric decreasing amount of the first zone fabric length and the second zone fabric length, and the fabric decreasing same amount at the first zone fabric length and the second zone fabric length, and the fabric increasing an amount at the third zone fabric length equal to a decreasing amount of the third zone chain length, and also equal to the sum of increasing amount of the first and second zones chain length; moving the tension balance moving bar and the fabric level moving and lowering means reciprocally and horizontally between the tracks concurrently opposite to each other such that the fabric above the fabric level moving and lowering means maintains a constant tension while moving reciprocally and horizontally and the an equal amount of the fabric is lowered and folded on the fabric loading board.
The invention also provides a buffer transient storing apparatus in the foregoing method. The buffer transient storing apparatus has a transmission link with a variable direction and variable speed wheel box driven by spinning power of a needle cylinder of the circular knitting machine. The variable direction and variable speed wheel box has two ends directing upwards to pivotally couple with the fabric spreading roller set to provide the spinning power so that the fabric spreading roller set is rotated synchronously with the needle cylinder in the same direction. The fabric spreading roller set is located horizontally in the circular knitting machine below the fabric knitted by the circular knitting machine. The variable direction and variable speed wheel box has a fabric loading board fastened thereon. The buffer transient storing apparatus includes: two corresponding fabric folding rails fastened to a lower side of two ends of the fabric spreading roller set hinged on an upper extension of the variable direction and variable speed wheel box and located horizontally in the circular knitting machine above the fabric loading board perpendicular to the fabric spreading roller set and having respectively a horizontal track corresponding to each other, a first fabric extending bar parallel with the fabric spreading roller set with two ends hinged on an outer side of the two tracks, a tension balance moving bar movable reciprocally and horizontally on the tracks parallel with the fabric spreading roller set and with two ends straddled the tracks, a second fabric extending bar parallel with the fabric spreading roller set with two ends hinged on another outer side of the two tracks at the same side of the first fabric extending bar, two first chain holding spots fastened to other outer sides of the tracks, two chain turning axles hinged on the outer side of the tracks same as the first chain holding spots, two fabric level moving and lowering means located on the twp fabric folding rails movable reciprocally and horizontally between the second fabric extending bar and the chain turning axles, and a forward turning fabric folding bar and a reverse turning fabric folding bar that are hinged on the fabric level moving and lowering means in a straddle manner parallel with each other horizontally and also parallel with the fabric spreading roller set and having spinning power. The two fabric level moving and lowering means have respectively a second chain holding spot, two chains each having one end fastened to the first chain holding spot and another end winding about a side end of the tension balance moving bar and the chain turning axle in a reverse manner to fasten to the two second chain holding spots.
The invention further provides a full-width fabric folding machine adopted the aforesaid buffer transient storing apparatus. The full-width fabric folding machine includes a variable direction and variable speed wheel box driven by spinning power of a needle cylinder of a circular knitting machine. The variable direction and variable speed wheel box is located at the bottom of the circular knitting machine to rotate synchronously with the needle cylinder in the same direction, and has two ends with a first side board and a second side board located thereon directing upwards to be bridged by a fabric loading board. The full-width fabric folding machine further has a fabric spreading roller set hinged on the first and second side boards below the fabric knitted by the circular knitting machine and above the fabric loading board to form a transmission link with the variable direction and variable speed wheel box, a driving means hinged on the second side board to form a transmission link with the fabric spreading roller set, and a buffer transient storing apparatus located between the fabric spreading roller set and the fabric loading board. The buffer transient storing apparatus has two fabric folding rails fastened to the first and second side boards. The driving means forms a transmission link with the fabric level moving and lowering means located on the fabric folding rails on the second side board.
Compared to the methods and techniques of lowering and folding fabric adopted by the conventional half-width and full-width fabric folding machines, the foregoing method provided by the invention has many advantages, notably:
1. The invention is a full-width fabric folding machine with maximum fabric holding capacity, and produces minimum scraps after fabric dyeing compared with the half-width fabric folding machine. Hence it can reduce labor and material costs.
2. The full-width fabric folding machine of the invention can move the transverse fabric repeatedly for transient storing and delivering and also maintain flat tension for the transverse fabric during the fabric folding return cycle. Thus the amount of the fabric being lowered is same as knitted and unloaded by the circular knitting machine. The fabric being lowered is flat and the problem of machine jam can be prevented. As a result, the circular knitting machine has improved knitting efficiency.
3. The full-width fabric folding machine of the invention performs fabric lowering at the same amount as the fabric unloading from the circular knitting machine through a mechanical approach without relying on programmable controllers. Thus its production cost is lower and earth resource waste also can be reduced.
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B are plane views of a conventional full-width fabric folding machine in fabric folding operations.
FIG. 2 is a perspective view of the full-width fabric folding machine of the invention.
FIG. 3 is another perspective view of the full-width fabric folding machine of the invention according to FIG. 2 viewing from the bottom.
FIG. 4 is a fragmentary enlarged view according to FIG. 2 .
FIGS. 5A through 5D are schematic views of the buffer transient storing apparatus of the invention in consecutive operating conditions.
FIG. 6 is a fragmentary exploded view of the fabric level moving and lowering means according to FIG. 4 .
FIG. 7 is a fragmentary plane view of the fabric spreading roller set of the invention in a transmission link condition.
FIG. 8 is a plane view of the driving means of the invention in a transmission link condition.
FIGS. 9A through 9E are fragmentary schematic views of the driving means according to FIG. 8 in consecutive operating conditions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Please referring to FIGS. 2 , 3 and 4 , the present invention provides a full-width fabric folding machine 10 which is located at the bottom in the interior of a circular knitting machine and rotates synchronously with a needle cylinder of the circular knitting machine in the same direction, and has a variable direction and variable speed wheel box 20 driven by the spinning power of the needle cylinder through a transmission link. The variable direction and variable speed wheel box 20 has a first side board 21 and a second side board 22 extended upwards from two ends thereof. The first and second side boards 21 and 22 are bridged by a fabric loading board 23 above the variable direction and variable speed wheel box 20 . The two side boards 21 and 22 also are horizontally hinged between them by two ends of a fabric spreading roller set 40 below a fabric 60 knitted by the circular knitting machine and above the fabric loading board 23 . Also referring to FIG. 7 , the fabric spreading roller set 40 includes a main fabric spreading roller 41 , a first driven roller 42 at one side of the main fabric spreading roller 41 rotating synchronously in a reverse direction against the main fabric spreading roller 41 and a second driven roller 43 at another side of the main fabric spreading roller 41 rotating synchronously in the reverse direction against the main fabric spreading roller 41 . The main fabric spreading roller 41 is driven by the spinning power of the variable direction and variable speed wheel box 20 through another transmission link.
The full-width fabric folding machine 10 of the invention further has a buffer transient storing apparatus 50 located between the fabric spreading roller set 40 and the fabric loading board 23 . Also referring to FIGS. 4 , 5 A and 6 , the buffer transient storing apparatus 50 includes two corresponding fabric folding rails 51 which are fixedly fastened to the first and second side boards 21 and 22 extended upwards from the variable direction and variable speed wheel box 20 , and below two ends of the fabric spreading roller set 40 and above the fabric loading board 23 in a horizontal manner and perpendicular to the fabric spreading roller set 40 . The two fabric folding rails 51 have respectively a horizontal track 514 corresponding to each other, a first fabric extending bar 54 parallel with the fabric spreading roller set 40 with two ends hinged on an outer side of the two tracks 514 , a tension balance moving bar 53 movable reciprocally and horizontally on the tracks 514 in parallel with the fabric spreading roller set 40 with two ends straddling the tracks 514 , a second fabric extending bar 55 parallel with the fabric spreading roller set 40 with two ends hinged on the outer side of the two tracks 514 same as the first fabric extending bar 54 , two first chain holding spots 511 fastened to another outer side of the tracks 514 , two chain turning axles 512 corresponding to each other and hinged on the outer side of the tracks 514 same as the first chain holding spot 511 , two fabric level moving and lowering means 52 located on the two fabric folding rails 51 and movable reciprocally and horizontally between the second fabric extending bar 55 and the chain turning axles 512 , and a forward turning fabric folding bar 521 and a reverse turning fabric folding bar 522 that are hinged in a straddle manner on the fabric level moving and lowering means 52 parallel with each other horizontally and equipped with spinning power. The forward turning fabric folding bar 521 and reverse turning fabric folding bar 522 are parallel with the fabric spreading roller set 40 . The two fabric level moving and lowering means 52 further have respectively a second chain holding spot 527 , two chains 70 each having one end fastened to the first chain holding spot 511 and another end winding about a side end of the tension balance moving bar 53 and the chain turning axle 512 in a reverse manner to fasten to the two second chain holding spots 527 . Each of the two fabric folding rails 51 further has a gear rack 513 fastened to an upper side of the track 514 . The gear rack 513 is formed at a length less that the interval of the second fabric extending bar 55 and the chain turning axle 512 . The forward turning fabric folding bar 521 has two ends fastened respectively to a first one-way gear 523 and a forward turning gear 525 . The reverse turning fabric folding bar 522 also has two ends fastened respectively to a second one-way gear 524 and a reverse turning gear 526 . The first and second one-way gears 523 and 524 are at one end of the forward and reverse turning fabric folding bars 521 and 522 of the same side to engage with the gear rack 513 at the same side, and the forward turning gear 525 and reverse turning gear 526 at the other end are engaged with each other.
The full-width fabric folding machine 10 of the invention further has a driving means 30 hinged on the second side board 22 to form a transmission link with the fabric spreading roller set 40 . Referring to FIGS. 8 and 9B , the driving means 30 includes a cam driving wheel 31 hinged on the second side board 22 and engaged with the main fabric spreading roller 41 to transmit rotation synchronously in the reverse direction, and a cam driven wheel 32 hinged on the outer side of the second side board 22 to form a transmission link with the cam driving wheel 31 to rotate synchronously in the same direction. The cam driving wheel 31 and the cam driven wheel 32 are coupled through a linking chain 311 to form the transmission link. The linking chain 311 may be a belt, chain or gears. The driving means 30 further has a cam 33 hinged on the outer side of the second side board 22 and fastened to the cam driven wheel 32 to rotate synchronously in the same direction. The cam 33 has a cam track 331 consisting of two symmetrical and indented arched paths. There is also an actuation wheel 34 hinged on the outer side of the second board 22 with an actuation member 341 fastened thereon and held in a protrusive manner in the cam track 331 and movable along the path of the cam track 331 to swing the actuation wheel 34 in an oscillation manner. There is also a transmission wheel 35 hinged on the outer side of the second board 22 to form a transmission link with the actuation wheel 34 to swing thereof synchronously in the reverse direction. There is further an oscillation arm 36 with one end located at an inner side of the second side board 22 to fasten to the transmission wheel 35 and another end hinged on a triple-axis lever 37 . The triple-axis lever 37 has one end hinged on the fabric level moving and lowering means 52 and another end hinged on a slider 371 at the inner side of the second side board 22 . There is a slide track 38 to allow the slider 371 to slide on a straight line. The slide track 38 is vertically located on the inner side of the second side board 22 . The transmission wheel 35 is connected to a transmission shaft 352 to transmit movement concurrently in the same direction. The transmission wheel 35 and the transmission shaft 352 are bridged by a transmission linking chain 351 to link transmission therebetween. The transmission linking chain 351 may be a belt, a chain or gears. The transmission shaft 352 can transmit movement concurrently in the same direction to the fabric level moving and lowering means 52 located on the first side board 21 .
When the fabric level moving and lowering means 52 is moved the forward turning fabric folding bar 512 and the reverse turning fabric folding bar 522 rotate continuously and synchronously in opposite directions. To further elaborate such operation, referring to FIGS. 4 and 6 , as previously discussed, the gear rack 513 is fastened to the upper side of the track 514 . The forward turning fabric folding bar 521 has the two ends fastened respectively to the first one-way gear 523 and the forward turning gear 525 . The reverse turning fabric folding bar 522 also has the two ends fastened respectively to the second one-way gear 524 and the reverse turning gear 526 . The first and second one-way gears 523 and 524 are coupled respectively with a one-way bearing with a shaft driven by forces of different directions to rotate (such a technique is known in the art, thus detailed drawings and discussion are omitted herein). Hence the first one-way gear 523 and the second one-way gear 524 at the same side of the forward and reverse turning fabric folding bars 521 and 522 are positioned in a front and rear manner to engage with the gear rack 513 . Thus when the fabric level moving and lowering means 52 is moved rightwards the one-way bearing shaft coupled with the first one-way gear 523 is not driven and idled, while the another one-way bearing shaft coupled with the second one-way gear 524 is driven. Hence the second one-way gear 524 is engaged with the gear rack 513 to generate rotation to drive the reverse turning fabric folding bar 522 to rotate concurrently counterclockwise, while the first one-way gear 523 is engaged with the gear rack 513 but not engaged with the second one-way gear 524 , hence even though the first one-way gear 523 rotates counterclockwise due to the gear rack 513 , its one-way bearing shaft is not being driven and becomes idled so that the forward turning fabric folding bar 521 fastened to the one-way bearing shaft also is not driven and is idled. However, because the forward turning fabric folding bar 521 and the reverse turning fabric folding bar 522 still have the forward turning gear 525 and reverse turning gear 526 engaged on the same side, when the reverse turning fabric folding bar 522 rotates counterclockwise the reverse turning gear 526 also rotates concurrently counterclockwise, and the engaged forward turning gear 525 is driven to rotate concurrently clockwise to drive the forward turning fabric folding bar 521 to rotate concurrently clockwise. On the other hand, when the fabric level moving and lowering means 52 is moved leftwards the another one-way bearing shaft coupled with the second one-way gear 524 is not driven and is idled, while the one-way bearing shaft coupled with the first one-way gear 523 is driven. Hence the first one-way gear 523 is engaged with the gear rack 513 to generate rotation to drive the forward turning fabric folding bar 521 to rotate concurrently clockwise, while the second one-way gear 524 is engaged with the gear rack 513 but not engaged with the first one-way gear 523 , hence even though the second one-way gear 524 rotates clockwise due to the gear rack 513 , its one-way bearing shaft is not being driven and becomes idled so that the reverse turning fabric folding bar 522 fastened to the one-way bearing shaft also is not driven and is idled. However, because the forward turning fabric folding bar 521 and the reverse turning fabric folding bar 522 still have the forward turning gear 525 and reverse turning gear 526 engaged on the same side, when the forward turning fabric folding bar 521 rotates clockwise the forward turning gear 525 also rotates concurrently clockwise, and the engaged reverse turning gear 526 is driven to rotate concurrently counterclockwise to drive the reverse turning fabric folding bar 522 to rotate concurrently counterclockwise.
Refer to FIGS. 5A through 5D for the buffer transient storing apparatus of the invention in consecutive operating conditions. The fabric spreading roller set 40 is horizontally located below the fabric 60 knitted by the circular knitting machine. The fabric spreading roller set 40 has a main fabric spreading roller 41 , a first driven roller 42 at one side of the main fabric spreading roller 41 to be driven to rotate concurrently in the opposite direction and a second driven roller 43 at another side of the main fabric spreading roller 41 to be driven to rotate concurrently in the opposite direction. As shown in the drawings, the fabric 60 knitted by the circular knitting machine is wound between the main fabric spreading roller 41 and the first driven roller 42 to another side of the main fabric spreading roller 41 and winding out from the second driven roller 43 . The fabric 60 wound on the fabric spreading roller set 40 is flattened and winds out from the right hand side thereof. The fabric 60 winding out from the fabric spreading roller set 40 further winds on the first fabric extending bar 54 hinged on the fabric folding rails 51 below the fabric spreading roller set 40 and winds out at the lower side to the left side direction. The fabric 60 winding out from the first extending bar 54 winds again on the tension balance moving bar 53 straddled the tracks 514 and winds out at the lower side to the right direction so that the first fabric extending bar 54 and the tension balance moving bar 53 are spaced from each other at a distance of a first zone fabric length X 1 . The fabric 60 winding out from the tension balance moving bar 53 further winds on the second fabric extending bar 55 hinged on the fabric folding rails 51 at the right side of the tension balance moving bar 53 and winds out at the lower side in the left direction so that the tension balance moving bar 53 and the second fabric extending bar 55 are spaced from each other to form a second zone fabric length X 2 . The fabric 60 winding out from the second fabric extending bar 55 further winds on the fabric level moving and lowering means 52 which moves reciprocally and horizontally on the tracks 514 . As the fabric level moving and lowering means 52 has the forward turning fabric folding bar 521 and reverse turning fabric folding bar 522 hinged horizontally thereon and equipped with spinning power, the fabric 60 winding out from the second fabric extending bar 55 winds between the forward turning fabric folding bar 521 and reverse turning fabric folding bar 522 and is lowered beneath between the forward and reverse turning fabric folding bars 521 and 522 at an amount same as continuously knitted by the circular knitting machine, and the second fabric extending bar 55 and the interval of the forward and reverse turning fabric folding bars 521 and 522 are spaced to form a third zone fabric length X 3 . The fabric held in the buffer transient storing apparatus 50 has a total length X which is the sum of the first zone fabric length X 1 and the second zone fabric length X 2 and the third zone fabric length X 3 , namely, X=X 1 +X 2 +X 3 . In addition, the fabric level moving and lower means 52 has a second chain holding spot 527 . The chain 70 has one end fastened to the second chain holding spot 527 and another end winding leftwards on the chain turning axle 512 hinged on the outer side of the track 514 and winding out from the upper side in the right direction. The second chain holding spot 527 and the chain turning axle 512 are spaced from each other to form a third zone chain length Y 3 . The chain 70 winding out from the chain turning axle 512 winds on a side end of the tension balance moving bar 53 and winds out from the upper side in the left direction. The chain turning axle 512 and the tension balance moving bar 53 are spaced from each other to form a second china zone length Y 2 . The chain 70 winding out from the tension balance moving bar 514 winds on the first chain holding spot 511 fastened to the track 514 to be anchored. The tension balance moving bar 53 and the first chain holding spot 511 are spaced from each other to form a first zone chain length Y 1 . The chain has a total length Y equal to the sum of the first zone chain length Y 1 and the second zone chain length Y 2 and the third zone chain length Y 3 , namely, Y=Y 1 +Y 2 +Y 3 . Referring to FIG. 5A , when the circular knitting machine continuously knits and lowers the fabric 60 , the fabric level moving and lowering means 52 starts moving horizontally rightwards. As the fabric level moving and lowering means 52 drives the tension balance moving bar 53 horizontally on the tracks 514 through the chain 70 , the tension balance moving bar 53 starts moving leftwards. Referring to FIG. 5B , while the fabric level moving and lowering means 52 moves horizontally rightwards, the forward and reverse turning fabric folding bars 521 and 522 lower the fabric through the gear rack 513 at an amount same as the knitted and unloaded fabric of the circular knitting machine. Hence the length of the fabric continuously knitted and unloaded by the circular knitting machine is equal to the horizontal moving distance of the fabric level moving and lowering means 52 , namely same as the length of the fabric lowering amount from the forward and reverse turning fabric folding bars 521 and 522 . For example, given L 1 for the fabric unloading length knitted continuously by the circular knitting machine as shown from FIG. 5A to FIG. 5B , the rightward horizontal moving distance of the fabric level moving and lowering means 52 from FIG. 5A to FIG. 5B also is L 1 . Due to the forward and reverse turning fabric folding bars 521 and 522 are engaged with the gear rack 513 , the fabric lowering amount of the level moving and lowering means 52 also is equal to L 1 . The fabric length L 1 unloaded by the circular knitting machine is equal to the fabric lowering length L 1 from between the forward and reverse turning fabric folding bars 521 and 522 that is laid flatly on the fabric loading board 23 . The level moving and lowering means 52 moves horizontally rightwards at the distance L 1 , meanwhile the tension balance moving bar 53 of the buffer transient storing apparatus 50 moves concurrently and horizontally leftwards, as a result, the first zone fabric length X 1 increases one half of L 1 (namely L 1 / 2 ), plus the second zone fabric length X 2 adding one half of L 1 (namely L 1 / 2 ) to be absorbed and held temporarily. Namely, when the fabric level moving and lowering means 52 moves horizontally rightwards between the second fabric extending bar 55 and the chain turning axle 512 , the third zone fabric length X 3 reduces the fabric length L 1 equal to the increased fabric length L 1 / 2 of the first zone fabric length X 1 plus the increased fabric length L 1 / 2 of the second zone fabric length X 2 . The increased fabric length L 1 / 2 of the first zone fabric length X 1 also is equal to the increased length L 1 / 2 of the second zone fabric length X 2 . The third zone fabric length X 3 reduces the length L 1 equal to the increased length L 1 of the third zone chain length L 1 , and also equals to the reduced length L 1 / 2 of the first zone chain length Y 1 plus the reduced length L 1 / 2 of the second zone chain length Y 2 . When the circular knitting machine continuously knits and unloads the fabric at a length L 2 as shown from FIG. 5B to FIG. 5C , the fabric level moving and lowering means 52 also moves rightwards horizontal at the distance L 2 as shown from FIG. 5B to FIG. 5C . Due to the forward and reverse turning fabric folding bars 521 and 522 are engaged with the gear rack 513 , the fabric lowering amount of the level moving and lowering means 52 also is equal to L 2 . The fabric length L 2 unloaded by the circular knitting machine is equal to the fabric lowering length L 2 from between the forward and reverse turning fabric folding bars 521 and 522 that is laid flatly on the fabric loading board 23 . The level moving and lowering means 52 moves horizontally rightwards at the distance L 2 , meanwhile the tension balance moving bar 53 of the buffer transient storing apparatus 50 moves concurrently and horizontally leftwards, as a result, the first zone fabric length X 1 increases one half of L 2 (namely L 2 / 2 ), plus the second zone fabric length X 2 also adding one half of L 2 (namely L 2 / 2 ) to be absorbed and held temporarily. Namely, when the fabric level moving and lowering means 52 moves horizontally rightwards between the second fabric extending bar 55 and the chain turning axle 512 , the third zone fabric length X 3 reduces fabric length L 2 equal to the increased fabric length L 2 / 2 of the first zone fabric length X 1 plus the increased fabric length L 2 / 2 of the second zone fabric length X 2 . The increased fabric length L 2 / 2 of the first zone fabric length X 1 is equal to the increased length L 2 / 2 of the second zone fabric length X 2 , and the reduced fabric length L 2 of the third zone fabric length X 3 is equal to the increased length L 2 of the third zone chain length Y 3 , and also equals to the reduced length L 2 / 2 of the first zone chain length Y 1 plus the reduced length L 2 / 2 of the second zone chain length Y 2 . When the circular knitting machine continuously knits and unloads the fabric at a length L 3 as shown from FIG. 5C to FIG. 5D , the fabric level moving and lowering means 52 also moves rightwards horizontal at the distance L 3 . Due to the forward and reverse turning fabric folding bars 521 and 522 are engaged with the gear rack 513 , the fabric lowering amount of the level moving and lowering means 52 also is equal to L 3 . The fabric length L 3 unloaded by the circular knitting machine is equal to the fabric lowering length L 3 from between the forward and reverse turning fabric folding bars 521 and 522 that is laid flatly on the fabric loading board 23 , and overlapped with the length L 2 shown in FIG. 5C . The level moving and lowering means 52 moves horizontally leftwards at the distance L 3 , meanwhile the tension balance moving bar 53 of the buffer transient storing apparatus 50 moves concurrently and horizontally rightwards, as a result, the first zone fabric length X 1 reduces one half of L 3 (namely L 3 / 2 ), and the second zone fabric length X 2 also reduces one half of L 3 (namely L 3 / 2 ) that are replenished by the fabric 60 held in the buffer transient storing apparatus 50 . Namely, when the fabric level moving and lowering means 52 moves horizontally rightwards between the second fabric extending bar 55 and the chain turning axle 512 , the fabric increasing length L 3 of the third zone fabric length X 3 is equal to the reduced fabric length L 3 / 2 of the first zone fabric length X 1 plus the reduced fabric length L 3 / 2 of the second zone fabric length X 2 . The reduced fabric length L 3 / 2 of the first zone fabric length X 1 is equal to the reduced length L 3 / 2 of the second zone fabric length X 2 , and the increased length L 3 of the third zone fabric length X 3 is equal to the reduced length L 3 of the third zone chain length Y 3 , and also equals to the increased length L 3 / 2 of the first zone chain length Y 1 plus the increased length L 3 / 2 of the second zone chain length Y 2 . Thus while the level moving and lowering means 52 moves continuously reciprocally and horizontally the fabric 60 held in the buffer transient storing apparatus 50 above maintains a constant tension without sagging or impact the moving path of the level moving and lowering means 52 . The level moving and lowering means 52 also can lower the fabric at an amount same as the unloading fabric continuously knitted by the circular knitting machine, and the fabric is folded and stacked onto the fabric loading board 23 .
Referring to FIG. 7 , the fabric spreading roller set 40 includes a main fabric spreading roller 41 , a first driven roller 42 at one side of the main fabric spreading roller 41 to rotate concurrently in the opposite direction and a second driven roller 43 at another side of the main fabric spreading roller 41 to rotate concurrently in the opposite direction. The variable direction and variable speed wheel box 20 transmits motion to the main fabric spreading roller 41 through the first side board 21 to continuously generate spinning power counterclockwise. Refer to FIGS. 8 and 9A through 9 E for driving means 30 of the invention in a transmission link and consecutive operating conditions. As shown in FIG. 8 , the driving means 30 has a cam driving wheel 31 hinged on the second side board 22 engaged with the main fabric spreading roller 41 to be driven to rotate concurrently clockwise. The cam driving wheel 31 rotating clockwise drives the cam driven wheel 32 at the lower side to rotate clockwise concurrently. Due to the cam driven wheel 32 is fastened to a cam 33 , they rotate concurrently clockwise. Referring to FIG. 9A , the cam 33 has a cam track 331 consisting of two symmetrical indented arched paths. The second side board 22 has an actuation wheel 34 hinged on the outer side thereof that has a jutting actuation member 341 held in the cam track 331 . When the cam 33 rotates continuously clockwise the actuation member 341 is directed by the cam track 331 to turn clockwise, meanwhile the transmission wheel 35 hinged on the outer side of the second side board 22 is driven by the actuation wheel 34 to turn counterclockwise. The oscillation arm 36 fastened to the transmission wheel 35 oscillates clockwise as shown in FIG. 9B , and the oscillation arm 36 has a triple-axis lever 37 hinged thereon that has one end hinged on the fabric level moving and lowering means 52 to move it horizontally rightwards and another end fastened to a slider 371 to slide up and down on the sliding track 38 formed on an inner side of the second side board 22 . Meanwhile, the cam 33 rotates continuously clockwise, and the actuation member 341 also is directed by the cam track 331 so that the actuation wheel 34 continuously turns clockwise, and the transmission wheel 35 is driven by the actuation wheel 34 to turn continuously counterclockwise. The oscillation arm 36 also oscillates continuously counterclockwise as shown in FIG. 9C . The fabric level moving and lowering means 52 hinged on one end of the tripe-axis lever 37 also continuously moves horizontally rightwards. When the oscillation arm 36 oscillates to move the fabric level moving and lowering means 52 beyond the slide track 38 , the slider 371 at another end of the triple-axis lever 37 starts sliding upwards on the slide track 38 , meanwhile the cam 33 continuously turns clockwise, and the actuation member 341 is directed by the cam track 331 to make the actuation wheel 34 to turn continuously clockwise. When the cam 33 continuously turns clockwise, the actuation member 341 is directed by the cam track 331 to arrive the junction of the two indented arched paths as shown in FIG. 9D . The actuation wheel 34 starts turning counterclockwise, and the transmission wheel 35 also is driven by the actuation wheel 34 to start turning clockwise, and the oscillation arm 36 also oscillates clockwise as shown in FIG. 9E . The fabric level moving and lowering means 52 hinged on the one end of triple-axis lever 37 starts moving horizontally leftwards, and the slider 371 at another end of the triple-axis lever 37 starts sliding downwards on the slide track 38 . Thus the cam 33 turns continuously clockwise and the oscillation arm 36 also oscillates in a non-stop cycle as shown in FIGS. 9A through 9E . The fabric level moving and lowering means 52 also is driven to move constantly in a reciprocal and horizontal fashion, and the slider 371 slides constantly up and down on the slide track 38 . As a result, the fabric level moving and lowering means 52 can be moved reciprocally and horizontally.
While the preferred embodiments of the invention have been set forth for the purpose of disclosure, modifications of the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention. | A method and apparatus for lowering and folding fabric at the same amount knitted and unloaded by a circular knitting machine delivers a fabric continuously knitted by the circular knitting machine and temporarily holds and in a buffer transient storing apparatus which divides the fabric into three zone fabric lengths and delivers later Through the buffer transient storing apparatus the three zone fabric lengths can complement with each other mechanically so that the fabric above the reciprocal moving of the forward and reverse turning fabric folding bars can be maintained at a constant tension, and the fabric knitted continuously by the circular knitting machine can be lowered at an equal amount and folded on a fabric loading board. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a light extraction substrate for an organic light-emitting device, a method of fabricating the same and an organic light-emitting device including the same, and more particularly, to a light extraction substrate for an organic light-emitting device which can overcome a problem that light extraction is caused mainly in a specific wavelength range in a conventional photonic crystal pattern having a periodic structure and can cause light extraction in a wider wavelength range, a method of fabricating the same and an organic light-emitting device including the same.
[0003] 2. Description of Related Art
[0004] In general, an organic light-emitting diode (OLED) includes an anode, a light-emitting layer and a cathode. When a voltage is applied between the anode and the cathode, holes are injected from the anode into a hole injection layer and then migrate from the hole injection layer through a hole transport layer to the organic light-emitting layer, and electrons are injected from the cathode into an electron injection layer and then migrate from the electron injection layer through an electron transport layer to the light-emitting layer. Holes and electrons that are injected into the light-emitting layer recombine with each other in the light-emitting layer, thereby generating excitons. When such excitons transit from the excited state to the ground state, light is emitted.
[0005] Organic light-emitting devices including an OLED are divided into a passive matrix type and an active matrix type depending on the mechanism that drives the N*M number of pixels which are arranged in the shape of a matrix.
[0006] In an active matrix type, a pixel electrode which defines a light-emitting area and a unit pixel driving circuit which applies a current or voltage to the pixel electrode are positioned in a unit pixel area. The unit pixel driving circuit has at least two thin-film transistors (TFTs) and one capacitor. Due to this configuration, the unit pixel driving circuit can supply a constant current irrespective of the number of pixels, thereby realizing uniform luminance. The active matrix type organic light-emitting display consumes little power, and thus can be advantageously applied to high definition displays and large displays.
[0007] However, as shown in FIG. 5 , only about 20% of light generated by an OLED is emitted to the outside and about 80% of the light is lost by a waveguide effect originating from the difference in the refractive index between a glass substrate 10 and an anode 20 , and an organic light-emitting layer 30 which includes a hole injection layer and a hole transport layer 31 , an emissive layer 32 , and an electron transport layer and an electron injection layer 33 and by a total internal reflection originating from the difference in the refractive index between the glass substrate 10 and the air. Specifically, the refractive index of the internal organic light-emitting layer 30 ranges from 1.7 to 1.8, whereas the refractive index of indium tin oxide (ITO) which is generally used for the anode 20 ranges from 1.8 to 1.9. Since the two layers have a very small thickness ranging from 200 to 400 nm and the refractive index of glass used for the glass substrate 10 is about 1.5, a planar waveguide is thereby caused inside the organic light-emitting device. It is calculated that the ratio of the light lost in the internal waveguide mode due to the above-described reason is about 45%. In addition, since the refractive index of the glass substrate 10 is about 1.5 and the refractive index of the ambient air is 1.0, when the light is directed outward from the inside of the glass substrate 10 , a ray of the light having an angle of incidence greater than a critical angle is totally reflected and is trapped inside the glass substrate 10 . Since the ratio of the trapped light is up to about 35%, only about 20% of the generated light is emitted to the outside.
[0008] In order to improve the luminous efficiency of an organic light-emitting device, a variety of conventional light extraction approaches was proposed. One of these light extraction approaches employs a photonic crystal structure that has a periodic pattern to extract light, the periodic pattern being formed at the front side of the organic light-emitting device through which light from the OLED is emitted. The size and period of the photonic crystal structure depend on a wavelength, and thus improvement in light extraction is limited to a specific wavelength range. The photonic crystal structure causes a phenomenon in which the peak of one wavelength in a specific wavelength range is higher than that of other wavelengths or the wavelength peak is shifted. Accordingly, the conventional photonic crystal structure is not applicable to white organic light-emitting devices for lighting application, the uniform luminous intensity of which must be obtained in a wide wavelength range.
[0009] The information disclosed in the Background of the Invention section is provided only for better understanding of the background of the invention and should not be taken as an acknowledgment or any form of suggestion that this information forms a prior art that would already be known to a person skilled in the art.
BRIEF SUMMARY OF THE INVENTION
[0010] Various aspects of the present invention provide an organic light-emitting device which can overcome a problem that light extraction depends on a wavelength range in a conventional photonic crystal pattern having a periodic structure and can cause light extraction in a wider wavelength range, a method of fabricating the same and an organic light-emitting device including the same.
[0011] In an aspect of the present invention, provided is a light extraction substrate disposed on one surface of an OLED through which light from the OLED is emitted. The light extraction substrate includes: a base substrate; a photonic crystal pattern disposed on the base substrate; and a planarization layer disposed on the photonic crystal pattern, one surface of the planarization layer adjoining the OLED. A number of air voids having random (various) shapes and sizes are irregularly distributed between the photonic crystal and the planarization layer.
[0012] According to an embodiment of the present invention, the photonic crystal may include: a base section disposed on the base substrate; and an embossed section disposed integrally on an upper portion of the base section.
[0013] The thickness of the base section may range from 820 to 880 nm.
[0014] The thickness of raised parts of the embossed section may range from 270 to 320 nm.
[0015] The total thickness of the embossed section and the planarization layer may range from 800 to 830 nm.
[0016] The number of air voids may be disposed between the planarization layer and depressed parts of the embossed section.
[0017] The photonic crystal pattern may be made of a resin.
[0018] The planarization layer may be made of a material, the refractive index of which is higher than the refractive index of the photonic crystal pattern.
[0019] In another aspect of the present invention, provided is a method of fabricating a light extraction substrate which is disposed on one surface of an OLED through which light from the OLED is emitted. The method includes the following steps of: forming a photonic crystal pattern on a base substrate; and forming a planarization layer on the photonic crystal pattern by a process resulting in thermal effect, leaving a number of air voids between the photonic crystal pattern and the planarization layer, the number of air voids having random (various) shapes and being irregularly distributed.
[0020] According to an embodiment of the present invention, the step of forming the photonic crystal pattern may include forming the photonic crystal pattern of a resin.
[0021] The step of forming the photonic crystal pattern may include forming the photonic crystal pattern by nanoimprint lithography.
[0022] The refractive index of the material that forms the planarization layer at the step of forming the planarization layer may be higher than the refractive index of the photonic crystal pattern.
[0023] The step of forming the planarization layer may include forming the planarization layer by an electron beam (E-beam) process.
[0024] In a further aspect of the present invention, provided is an organic light-emitting device that includes the above-described light extraction substrate on one surface of an OLED through which light from the OLED is emitted.
[0025] According to an embodiment of the present invention, the organic light-emitting device may be a white light-emitting device for lighting application.
[0026] In the light extraction substrate according to embodiments of the present invention in which the photonic crystal pattern having a periodic structure and the planarization layer are disposed at the front side of the OLED through which light from the OLED is emitted to form a light extraction layer in order to improve the light extraction efficiency of the organic light-emitting device, the number of air voids having random (various) shapes are irregularly distributed between the photonic crystal pattern and the planarization layer in order to reduce the periodicity or regularity of the photonic crystal pattern. It is therefore possible to overcome a problem that light extraction is caused mainly in a wavelength range in the photonic crystal pattern having a periodic structure and to cause light extraction in a wider wavelength range. Accordingly, the light extraction substrate can be applied as an internal light extraction substrate of a white organic light-emitting device for lighting application.
[0027] The methods and apparatuses of the present invention have other features and advantages which will be apparent from, or are set forth in greater detail in the accompanying drawings, which are incorporated herein, and in the following Detailed Description of the Invention, which together serve to explain certain principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a cross-sectional view schematically showing an organic light-emitting device which has a light extraction substrate according to one exemplary embodiment of the present invention as an internal light extraction substrate of an organic light-emitting device;
[0029] FIG. 2 is an electron microscopy picture showing the cross-section of a light extraction substrate for an organic light-emitting device according to an exemplary embodiment of the present invention;
[0030] FIG. 3 is electron microscopy pictures showing the surface of a photonic crystal pattern of a light extraction substrate for an organic light-emitting device according to an exemplary embodiment of the present invention;
[0031] FIG. 4 is a graph showing variations in luminous intensity depending on the refractive index of a planarization layer of a light extraction substrate for an organic light-emitting device according to an exemplary embodiment of the present invention;
[0032] and
[0033] FIG. 5 is a conceptual cross-sectional view of a conventional organic light-emitting device for explaining the light extraction efficiency thereof.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Reference will now be made in detail to a light extraction substrate for a light-emitting device, a method of fabricating the same and an organic light-emitting device including the same according to the present invention, embodiments of which are illustrated in the accompanying drawings and described below, so that a person skilled in the art to which the present invention relates can easily put the present invention into practice.
[0035] Throughout this document, reference should be made to the drawings, in which the same reference numerals and signs are used throughout the different drawings to designate the same or similar components. In the following description of the present invention, detailed descriptions of known functions and components incorporated herein will be omitted when they may make the subject matter of the present invention unclear.
[0036] As shown in FIG. 1 , an organic light-emitting device according to this exemplary embodiment includes an OLED 1 and a light extraction substrate 100 which is disposed on one surface of the OLED 1 through which light from the OLED 1 is emitted in order to improve the light extraction efficiency of the OLED 1 .
[0037] Although not shown in detail, the OLED 1 has a multilayer structure in which an anode, an organic light-emitting layer and a cathode are sandwiched between the light extraction substrate 100 and a substrate that faces the light extraction substrate 100 . Here, the anode can be made of a metal or metal oxide, for example, Au, In, Sn or indium tin oxide (ITO), which has a significant work function in order to facilitate the hole injection. The cathode can be made of a metal thin film of, for example, Al, Al:Li or Mg:Ag, which has a smaller work function in order to facilitate the electron injection. When the organic light-emitting device is a top emission type organic light-emitting device, the cathode can have a multilayer structure that includes a semitransparent electrode of a metal thin film made of Al, Al:Li or Mg:Ag and a transparent electrode of an oxide thin film made of, for example, ITO, in order to facilitate the transmission of light that is generated from the organic light-emitting layer. The organic light-emitting layer includes a hole injection layer, a hole transport layer, an emissive layer, an electron transport layer and an electron injection layer which are sequentially stacked on the anode. Since the organic light-emitting device according to this exemplary embodiment is implemented as a white organic light-emitting device for lighting application, for example, the light-emitting layer can have a multilayer structure that includes a high-molecular light-emitting layer which emits blue light and a low-molecular light-emitting layer which emits orange-red light. The light-emitting layer can also have a variety of other structures to emit white light.
[0038] With this structure, when a forward voltage is induced between the anode and the cathode, electrons from the cathode migrate to the emissive layer through the electron injection layer and the electron transport layer, and holes from the anode migrate to the emissive layer through the hole injection layer and the hole transport layer. The electrons and holes that have migrated into the emissive layer recombine with each other, thereby generating excitons. When these excitons transit from an excited state to a ground state, light is emitted. The brightness of the light emitted is proportional to the amount of current that flows between the anode and the cathode.
[0039] The light extraction substrate 100 for an organic light-emitting device according to this exemplary embodiment includes a base substrate 110 , a photonic crystal pattern 120 and a planarization layer 130 .
[0040] The base substrate 110 is the substrate that supports the photonic crystal pattern 120 and the planarization layer 130 which are disposed on one surface thereof. The base substrate 110 is also disposed on the front side of the OLED 1 , i.e. in the direction in which light from the OLED 1 is emitted, and serves as an encapsulation substrate which allows the generated light to exit through while protecting the OLED 1 from the external environment.
[0041] The base substrate 110 can be a transparent substrate that has superior light transmittance and mechanical properties. For instance, the base substrate 110 can be made of a polymeric material, such as a thermally or ultraviolet (UV) curable organic film, or a chemically strengthened glass, such as soda-lime glass (SiO 2 —CaO—Na 2 O) or aluminosilicate glass (SiO 2 —Al 2 O 3 —Na 2 O). When the organic light-emitting device including the OLED 1 and the light extraction substrate 100 according to this exemplary embodiment is applied for lighting, the base substrate 110 can be made of soda-lime glass. The base substrate 110 can also be a substrate that is made of a metal oxide or a metal nitride. The base substrate 110 can be made of a piece of thin glass having a thickness of 1.5 mm or less. The thin glass can be made using a fusion process or a floating process.
[0042] The photonic crystal pattern 120 serves to diversify or increase paths along which light generated from the OLED 1 scatters, thereby improving the light extraction efficiency of the organic light-emitting device. The photonic crystal pattern 120 is disposed on the base substrate 110 . The photonic crystal pattern 120 includes a base section 121 and an embossed section 122 . The base section 121 is disposed on the base substrate 110 , and the embossed section 122 is formed integrally on the upper portion of the base section 121 . As shown in the electron microscopy pictures of FIG. 3 , the embossed section 122 can have a periodic structure. According to this exemplary embodiment, the thickness of the base section 121 may range from 820 to 880 nm, and the thickness of the raised parts of the embossed section 122 may range from 270 to 320 nm.
[0043] The photonic crystal pattern 120 having this structure can be made of a material, for example, a resin, the refractive index of which is lower than that of the planarization layer 130 . The photonic crystal pattern 120 can be formed by nanoimprint lithography (NIL), which will be described in greater detail later in relation to a method of fabricating a light extraction substrate for an organic light-emitting device.
[0044] The planarization layer 130 is disposed on the photonic crystal pattern 120 . The planarization layer 130 forms, together with the photonic crystal pattern 120 , an internal light extraction layer of the organic light-emitting device. Here, the surface of the planarization layer 130 disposed on the photonic crystal pattern 120 adjoins the OLED 1 , more particularly, the anode of the OLED 1 . As the surface of the planarization layer 130 adjoins the OLED 1 in this manner, the surface of the planarization layer 130 must have a high level of flatness in order to prevent the electrical characteristics of the organic light-emitting device from being deteriorated. When the planarization layer 130 is formed on the photonic crystal pattern 120 , the embossed section 122 of the photonic crystal pattern 120 may make the surface of the planarization layer 130 embossed. In order to prevent this, the planarization layer 130 is required to be sufficiently thick. For instance, when the thickness of the raised parts of the embossed section 122 ranges from 270 to 320 nm, the total thickness of the embossed section and the planarization layer 130 preferably ranges from 800 to 830 nm.
[0045] In addition, in order to prevent cracks, the planarization layer 130 can be made of a material, the coefficient of thermal expansion (CTE) of which is similar to that of a resin that is to form the photonic crystal pattern 120 . The planarization layer 130 can be made of a material, the refractive index of which is higher than that of the photonic crystal pattern 120 . The graph in FIG. 4 indicates that the luminous intensity increases with the increasing refractive index of the planarization layer 130 . It is therefore preferred that the planarization layer 130 be made of a material, the refractive index of which is higher than that of the photonic crystal pattern 120 , more particularly, a material, the refractive index n of which is 2.1 or greater. For instance, the planarization layer 130 can be made of a metal oxide, such as TiO 2 , SnO 2 , Al 2 O 3 or ZnO, or a metal nitride, such as SiN x .
[0046] As shown in FIG. 1 and FIG. 2 , a number of air voids 140 having random shapes and sizes are irregularly distributed between the photonic crystal pattern 120 and the planarization layer 130 which are stacked on each other. The number of air voids 140 may be concentrated mainly in the depressed parts of the embossed section 122 of the photonic crystal pattern 120 which tend to be left vacant when the planarization layer 130 is formed.
[0047] When the organic light-emitting device according to this exemplary embodiment is a white organic light-emitting device for lighting application, light extraction must be caused in a wide wavelength range. However, since the photonic crystal pattern 120 tends to have a periodic structure which significantly increases light extraction in a specific wavelength range, the requirement for the white organic light-emitting device for lighting application, i.e. light extraction in a wide wavelength range, is not achieved. In this case, the number of air voids 140 serve to reduce the periodicity or regularity of the photonic crystal pattern 120 . The number of air voids 140 formed between the photonic crystal pattern 120 and the planarization layer 130 also function like a number of light-scattering particles to scatter light along diverse paths, thereby causing light extraction in a wide wavelength range suitable to the white organic light-emitting device for lighting application. The characteristic of the number of air voids 140 may be adjusted by the moisture content of the material that forms the photonic crystal pattern 120 and the method of forming the planarization layer 130 . This will be described in greater detail later in relation to the method of fabricating a light extraction substrate for an organic light-emitting device.
[0048] A description will be given below of the method of fabricating a light extraction substrate for an organic light-emitting device according to an exemplary embodiment of the present invention. Reference numerals for the components of the light extraction substrate will refer to those in FIG. 1 .
[0049] The method of fabricating a light extraction substrate for an organic light-emitting device according to this exemplary embodiment is the method of fabricating the light extraction substrate 100 which is disposed on one surface of the OLED 1 through which light from the OLED 1 is emitted. The method includes a photonic crystal patterning step and a planarization layer forming step.
[0050] The photonic crystal patterning step is the step of forming the photonic crystal pattern 120 having a periodic structure on the base substrate 110 . At the photonic crystal patterning step, the photonic crystal pattern 120 can be made of a resin. In addition, the photonic crystal patterning step can form the photonic crystal pattern 120 by a nano imprint lithography (NIL) process. Specifically, the resin is applied on the base substrate 110 , is pressed using a nano-patterned template, and then is exposed to ultraviolet (UV) radiation. Afterwards, the template is removed from the cured resin, thereby leaving the photonic crystal pattern 120 made of the resin on the base substrate 110 . The photonic crystal pattern 120 formed by the NIL process includes the base section 121 and the embossed section 122 . According to this exemplary embodiment, the photonic crystal patterning step can control the NIL process such that the thickness of the base section 121 ranges from 820 to 880 nm and the thickness of the raised parts of the embossed section 122 ranges from 270 to 320 nm.
[0051] Afterwards, the planarization layer forming step is the step of forming the planarization layer 130 on the photonic crystal pattern 120 . According to this exemplary embodiment, the number of air voids 140 which have random shapes and sizes and are irregularly distributed are formed between the photonic crystal pattern 120 and the planarization layer 130 . The number of air voids 140 reduce the periodicity of the photonic crystal pattern 120 that has a periodic structure, thereby causing light extraction in a wider wavelength range rather than in a specific wavelength range. For this, at the planarization layer forming step, the planarization layer 130 is made of a material, for example, TiO 2 , the refractive index of which is higher than that of the photonic crystal pattern 120 . The number of air voids 140 can be formed using the moisture in the resin that forms the photonic crystal pattern 120 . Specifically, at the planarization layer forming step, the photonic crystal pattern 120 can be coated with the planarization layer 130 by a process resulting in thermal effect, such as an electron beam (E-beam) process. In this case, due to the evaporation of the moisture from the resin and the repulsive force of TiO 2 , the material that forms the planarization layer 130 , a number of small regions in the photonic crystal pattern 120 is left (at least partially) vacant without being filled up with TiO 2 , thereby forming the number of air voids 140 . Due to the structure of the photonic crystal pattern 120 , the number of air voids 140 can be concentrated in the depressed parts of the embossed section 122 . When the number of air voids 140 is formed or caused through the thermal interaction between the material that forms the photonic crystal pattern 120 and the material that forms the planarization layer 130 in this manner, the number of air voids 140 have random shapes and sizes and are irregularly distributed between the photonic crystal pattern 120 and the planarization layer 130 . The number of air voids 140 serve to destroy the periodicity of the photonic crystal pattern 120 having a periodic structure while scattering light generated from the OLED 1 along a variety of paths.
[0052] The surface of the planarization layer 130 formed on the photonic crystal pattern 120 at the planarization layer forming step must have a high level of flatness since the planarization layer 130 adjoins the anode of the OLED 1 . Therefore, at the planarization layer forming step, the planarization layer 130 is preferably formed as a thick film in order to prevent the shape of the embossed section 122 of the photonic crystal pattern 120 from being exposed on the surface of the planarization layer 130 , i.e. to prevent the embossed section 122 from causing an embossed surface of the planarization layer 130 . For instance, at the planarization layer forming step, the planarization layer 130 can be formed such that a total thickness of the embossed section and the planarization layer ranges from 800 to 830 nm when the thickness of the raised parts of the embossed section 122 ranges from 270 to 320 nm.
[0053] At the completion of the planarization layer forming step in this manner, the light extraction substrate 100 applicable for an internal light extraction substrate of the white organic light-emitting device for lighting application is fabricated.
[0054] As set forth above, the photonic crystal pattern 120 is formed from the resin that contains moisture by the NIL process, and then the planarization layer 130 is formed of a material that requires a thermal process. It is therefore possible to cause the number of air voids 140 to be formed between the photonic crystal pattern 120 and the planarization layer 130 such that the number of air voids 140 have random shapes and sizes and are irregularly distributed. This can consequently overcome light extraction dependency in a wavelength range that occurs in the photonic crystal pattern 120 having a periodic structure, and can cause light extraction in a wider wavelength range. Accordingly, the light extraction substrate 100 can be used as an internal light extraction substrate of the white organic light-emitting device for lighting application.
[0055] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented with respect to the drawings. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible for a person having ordinary skill in the art in light of the above teachings.
[0056] It is intended therefore that the scope of the present invention not be limited to the foregoing embodiments, but be defined by the Claims appended hereto and their equivalents. | The present invention relates to a light extraction substrate for an organic light-emitting element, a method for manufacturing the same and an organic light-emitting element including the same, which can shed its dependence on light extraction in a specific wavelength range appearing in a light determining pattern of a cyclical form and induce light extraction in a broader wavelength range. To this end, the present invention relates to a light extraction substrate for an organic light-emitting element, a method for manufacturing the same and an organic light-emitting element including the same. The light extraction substrate is disposed on one surface through which light emitted from the organic light-emitting element is outwardly released and comprises: a base substrate; a light determining pattern formed on the base substrate; and a leveling layer formed on the light determining pattern and having a surface contacting the organic light-emitting element, wherein a plurality of air voids having a random shape and size are irregularly distributed on an interface between the light determining pattern and the leveling layer. | 8 |
BACKGROUND
This specification relates to a package for a MEMS device. The disclosed embodiment is a package for a micromirror display device, often called a spatial light modulator, as is commonly used in projection displays. However, the package can be used for any MEMS device.
Micromirror projection display devices display an image by projecting light corresponding to the color channels of the image to be projected. A micromirror display device displays the pixels of the image by tilting mirror plates of micromirrors which, in one position, project light to the display (to display the pixel assigned to that mirror) and in the other position, deflect light away from the display (so as not to display the assigned pixel). It is important that the mirrors of micromirror devices tilt freely from one position to the other without any undesirable sticking at their end positions. To avoid sticking, the mirror packages usually contain an “antistiction” coating (usually referred to as “ASC”) which prevents such sticking.
The array of mirror plates in a micromirror device is commonly built on top of a CMOS wafer which contains all the required electrical circuitry for operation of the mirrors. In order for the device to operate reliably, all the mirrors and related structures need to be protected from ambient conditions by placing the device into a sealed, hermetic or semi-hermetic package. Such a package consists of three functional parts: (1) the micromirror substrate that includes the CMOS circuitry and the mirrors; (2) a transparent top cover (typically glass) which allows the incoming light beam to reach the mirrors so the light can be reflected towards the collecting optics; and (3) a seal which connects the micromirror substrate to the glass cover. The combination of these three parts creates a closed cavity surrounding the micromirror device structure.
The seal typically consists of epoxy which, during application, is in a viscous state so that it can easily be applied. After mating of the substrate and transparent cover, the epoxy must be cured into a hard material that provides the necessary mechanical strength to keep the package closed and sealed.
Curing epoxy, for example, using UV light or heat, will often result in the removal of solvents from the epoxy. Chemical analysis of these solvents shows that they contain benzene ring elements which are known to reduce the effect of the ASC used to keep the mirrors from sticking in one or the other of their end positions.
Modern fabrication techniques do not make micromirror devices one at a time. Instead, a wafer containing hundreds or more of the devices is manufactured and packaged all at once. The packaging process consists of the steps of: (1) dispensing the primary epoxy seal either on the substrate or on the glass cover; (2) mating the substrate and the glass cover; (3) curing the epoxy; and (4) dicing the wafer of sealed packages into individual, sealed and packaged devices (called “singulation”).
In order to maintain a defined tilt angle of the mirrors, it is desirable for a mirror to contact a landing post and be held against that post. When the mirror tilts over to the other side, the mirror will apply a substantial force to the landing post, which tends to displace the ASC on the post and to increase the adhesion of the mirror to the post. The displaced ASC needs to be replenished so as to recoat the surface of the landing post in order to minimize adhesion of the mirrors to the posts during the continuous operation of the mirrors. The ability to replenish the ASC depends, among other things, upon temperature, the presence or absence of moisture in the package and the quality of the ASC itself.
Therefore it is desirable to avoid ASC contamination. Such contamination can occur before and/or after introducing the ASC into the package. Experience has shown that epoxy outgassing of the package seal before the ASC is introduced can be a major source of ASC contamination. This contamination tends to increase the adhesion of the mirrors to the posts, both initially and later during reliability tests.
It is equally important not to allow moisture to get into the package. A high moisture level inside the package degrades device performance. Exposing the package to a combination of high temperature and humidity will cause moisture to get into the cavity containing the mirrors. A moisture-resistant seal is therefore required to avoid moisture from reaching the area of the package where the micromirror devices are.
One way of reducing moisture in the package is to reduce the seal thickness. As the seal material is the only material between the device substrate and the glass cover, the seal thickness must be thick enough, typically 10 um, to prevent the glass cover from ever touching the mirror surfaces at all angles to which the mirrors may be tilted during device operation. In addition, with less spacing between the substrate and the cover, defects in the glass surface will be closer to the mirror focal plane and hence more visible. Of course, as future devices become smaller, as they typically do, this minimum spacing will become smaller.
In order to reduce seal thickness to a more desirable thickness of less than 1 um, a spacer needs to be added on either the glass or the device side to prevent the mirrors from touching the glass cover and to render glass defects less visible. This spacer must be moisture-resistant. A highly moisture-resistant spacer can be achieved by bonding a third substrate to the glass cover, or by using Ni or Cu electroplating. But such solutions increase the number of process steps, complicating the manufacture of the devices and increasing their cost. As an alternative, a polymer resist material can be used to create a more cost effective physical structure, but these polymers have been found not to have the required moisture resistance required for micromirror devices.
One way the ASC can be applied to the packaged devices is through a hole in the seal, which afterwards must be closed, typically by using a plug. However, the moisture resistance around the plug tends to be less than that of the rest of the seal. Therefore creating a seal without using a plug is much more desirable. Furthermore, because plug-sealed devices must be individually tested after they sealed and diced, more manual handling is required, which can result in human error and is not well suited for mass production.
But creating a plugless seal requires that the ASC to be applied to the package before bonding of the two main parts, and the ASC, which is then present during sealing, must not be allowed to become degraded during the seal curing process. For example, creating a plugless seal using UV-curable epoxy in the presence of ASC beneath the seal material has been found to reduce the bonding strength of the seal.
Thermally cured epoxy results in acceptable seal bonding strength, even in the presence of ASC beneath the seal. However, the temperature required for curing thermal epoxy usually exceeds the ASC evaporation temperature, resulting in an undesirable loss of ASC during the sealing process.
SUMMARY
The improved moisture-resistant package for a MEMS device, as will be described in detail below, includes a substrate, such as a silicon substrate, on which are formed the electrical connections for the MEMS or micromirror devices, and the movable parts or movable micromirrors themselves. Micromirror devices are well known in the art and are described, for example, in U.S. Pat. No. 7,538,932 assigned to the same assignee as the subject invention. The package has a transparent, or at least, translucent cover over the substrate, and a seal and moisture barrier between the substrate and the cover.
The seal and moisture barrier includes a plurality of parallel sidewalls around the periphery of a substrate and cover, each of the sidewalls having ends and an area between the sidewalls. The sidewalls, preferably made from an organic material, such as photoresist, separate the substrate and cover by a sufficient distance to provide clearance for the movement of the movable parts. A glue layer at least partially fills the area between the sidewalls, and also between an end of the sidewalls and one of the substrate or cover. The glue layer causes the substrate or cover (whichever is attached to the ends of the sidewalls) to adhere to the end of the sidewalls.
Preferably, the sidewalls are coated with a moisture-resistant coating, or overcoat. This overcoat can be an inorganic material, such as aluminum oxide or zirconium oxide, or a combination of the two, preferably applied using an atomic layer deposition (ALD) process. This coating may also be a compound of silicon, for example, SiN, SiC or SiO x . Depending upon the type of coating used, the coating may be applied using an ALD, CVD or PVD process. The glue layer may be epoxy which can be placed between the ends of the sidewalls and the substrate or cover, at least partially into the gaps between the sidewalls, and preferably filling these gaps. At least two sidewalls are used, preferably at least three.
The method of fabricating the improved moisture-resistant package described herein includes the steps of: (a) forming a plurality of parallel sidewalls around the periphery of a substrate or a translucent cover, the substrate having attached movable parts (the sidewalls have ends and an area between them, and they separate the substrate and cover by a sufficient distance to provide clearance for the movement of the movable parts); (b) applying a moisture-resistant coating on the sidewalls; (c) applying an antistiction coating between the substrate and the cover; (d) applying a glue layer to the ends of the sidewalls and at least partially to the area between the sidewalls, the glue layer being capable of adhering the ends of the sidewalls to the substrate or cover; and (e) sealing the sidewalls and substrate or cover together using the glue layer as a seal. Making the package by this method prevents moisture from entering the package.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a package of one embodiment of the invention before it has been sealed;
FIG. 2 is a cross-sectional view of the cover of a package of one embodiment of the invention showing the sidewalls and the initially applied sealing material.
FIG. 3 is a cross-sectional view of the package of FIG. 1 after the sealing material has been applied within sidewalls.
FIG. 4 is a cross-sectional view of a package of FIG. 1 after it has been sealed;
FIG. 5 is a cross-sectional view of a package of another embodiment of the invention before it has been sealed;
FIG. 6 is a cross-sectional view of a package of FIG. 5 after it has been sealed;
FIG. 7 is a cross-sectional view of a package of yet another embodiment of the invention before it has been sealed; and
FIG. 8 is a cross-sectional view of a package of FIG. 7 after it has been sealed.
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
Referring to FIG. 1 , one embodiment of the moisture-resistant package of the invention is shown. These packages are generally square or rectangular in shape. Tilting mirrors 11 are mounted on substrate 10 , which may, for example be silicon. As shown, these mirrors 11 tilt to one side or the other depending upon the electrical signal applied to them, as is well known and described in the above-referenced U.S. Pat. No. 7,538,932. In order to protect the mirrors, they are sealed in the package by the attachment of a glass cover plate 12 . This cover plate 12 is square or rectangular, conforming to the size of the package. A plurality of sidewalls 14 are placed between the cover plate 12 and substrate 10 . In one embodiment, the plurality of sidewalls 14 are attached at the periphery of cover plate 12 by moisture-resistant seal 16 . Alternatively, sidewalls 14 may be attached at the periphery of the substrate 10 instead of attaching them to the periphery of cover plate 12 . In either case, the substrate 10 and cover plate 12 are later sealed. As FIG. 1 is a cross-section of the package, sidewalls 14 appear on opposites sides of the drawing, but in the actual package, they extend all around the square or rectangular periphery of the package.
After curing the epoxy seal, each panel on the wafer has to be physically separated into individual devices, a process called “singulation”. As part of the singulation process, the glass needs to be cut, for example using a dicing saw, either completely through the glass or at least a fraction of way through the total glass thickness. Where the glass is not cut through completely, the remaining unbroken part of the glass is broken by hand. The resulting interface between devices may not be smooth, providing a potential source of glass particles. Even if the glass is cut completely through, if the distance between substrate 10 and glass cover 12 is too small, the CMOS wafer beneath the glass could be damaged by the saw during the cutting process, particularly near the bond pad area where the device is connected to the package. Preferably, sidewalls 14 are at least 50 um high so that the mirrors will not be adversely affected by glass particles during singulation. In that case, the glass may be cut through completely, yielding a smooth edge and eliminating the labor intensive breaking process.
Sidewalls 14 may be made from organic or inorganic material, for example, photoresist material, glass frit or a metal such as nickel or copper. A preferred embodiment of the invention employs photoresist material for sidewalls 14 , for example TMMR S2000. This material can form sidewalls having a wide variety of thicknesses, for example, between about 5 and 700 um. In addition, this material enables forming sidewalls with high aspect ratios, for example, in excess of 20. The material has an excellent resistance to chemicals, allowing its use with many epoxy glue materials as well as other types of glue.
The photoresist has a high thermal resistance, enabling a high temperature sealing process to be used. As a specific example, a wall thickness of 130 um can be used. Using TMMR S2000 photoresist material for the sidewalls 14 , an exposure dosage of 400 mj/cm2 can be used, with a post exposure bake of the photoresist at about 90° C. for about 10 minutes. The photoresist can be developed using a chemical solvent, such as PM Thinner, at about 23° C. for about 30 minutes.
Alternatively, the sidewalls 14 can be made using polymeric materials, such as epoxy-based or polyimide-based photosensitive materials, that may be formed using well known lithographic processes. The epoxy-based photosensitive material such as SU-8 and polyimide-based material, such as Toray's PW-series materials, may be used. In the alternative, screen printing techniques may be used with conventional UV/thermally cured epoxies, where the curing temperatures are sufficiently low to avoid damage to the devices.
To further improve the moisture resistance of the sidewalls 14 , it has been found that a thin moisture-resistant coating, or overcoat 15 can be applied. This overcoat 15 is preferably as thin as necessary to achieve the desired amount of moisture resistance, as a thick overcoat takes longer to apply. It has been found that the effective overall moisture resistance of the sidewalls is improved even with a very thin overcoat.
Overcoat 15 may preferably be a transparent inorganic film which conformally overcoats sidewalls 14 , but the overcoat is not limited to transparent materials. For example, the overcoat can be an inorganic material, such as oxides of aluminum or zirconium. Other materials suitable for ALD deposition may also be used. In addition, materials deposited by CVD may be used, such as SiN, SiC and/or SiO x . Techniques for CVD deposition of these materials are well known in the art. However, as SiN and SiC are not transparent, care must be taken that these materials are not deposited in the active area of the mirrors, or if any material is accidentally deposited there, it must be removed. Alternatively, the overcoat 15 can be deposited using a PVD process known in the art, using materials such as SiO x , indium tin oxide (ITO) or other similar materials that may be deposited using a PVD process.
A preferred overcoat layer 15 is aluminum oxide deposited by an ALD process. To deposit the aluminum oxide, trimethyl aluminum (CH 3 ) 3 Al), known in the art as “TMA”, and moisture (H 2 O) are deposited in sequence and adsorbed onto the surface of sidewalls 14 . This deposition sequence is carried out repeatedly to form a layer of aluminum oxide. During each cycle of the process, excess TMA is purged, and then moisture is introduced to react with the adsorbed TMA to form the overcoat of aluminum oxide 15 . Multiple aluminum oxide layers can be continuously formed on the surface of sidewalls 14 by repeating the process, thereby thickening the aluminum oxide to the thickness required to obtain the necessary moisture resistance. The preferred deposition temperature is less than 200° C., as higher temperatures may damage the sidewalls 14 . It has been found that about five deposition cycles can be sufficient to obtain the desired amount of moisture resistance, but this can vary according to the materials used and the procedure used to deposit them. For example, 5 to 10 cycles of ALD can be used, or 100 to 200 cycles.
Furthermore, where multiple ALD sequences are used to deposit moisture-resistant layer 15 , other materials capable of being deposited using ALD can be used, such as zirconium oxide. Alternatively, layer 15 may be formed using composite materials, for example, using alternating layers of aluminum oxide and zirconium oxide, thereby obtaining a composite AlO x /ZrO x overcoat layer 15 on the sidewalls 14 to enhance its moisture resistance.
Next the ASC is applied to the device. Either before or after the epoxy material is applied, an ASC is deposited onto the substrate. This must be done before the package is sealed. The ASC can be applied by vapor phase deposition to the surface of the substrate 10 , or to both the surface of the substrate 10 and the underside of glass cover 12 . If desired, in addition to, or instead of vapor phase deposition of the ASC, ASC material may be deposited into the cavities of the device by getter absorption, by dosing with solution droplets, or by placing solid ASC material into the cavities, or a combination of some or all of these techniques.
Next, referring to FIG. 2 , an epoxy seal material 16 is dispensed into the sidewalls 14 . This epoxy seal material 16 will be used to form a bond between the glass cover 12 and substrate 10 . The epoxy seal material is preferably dispensed onto the ends 18 of sidewalls 14 as shown in FIG. 2 . By carefully selecting the dispensing conditions, such as the position of the epoxy dispenser relative to the substrate, and the amount of the sealant material dispensed and the rate of dispensing, the sealant can at least partially fill the gap between sidewalls 14 , as shown in FIG. 3 , but not spill over into the active area 24 , thereby preventing undesirable gasses from the epoxy from entering the active device area 24 where mirrors 11 are located.
Next, the cover 12 and substrate 10 are pressed together, as shown in FIG. 4 . The pressure applied in this step drives the epoxy material 16 to fill the space between the sidewalls 14 . The ends 18 of sidewalls 14 , which contact the substrate, can have a thin layer of epoxy on them, which will hold cover 12 and substrate 10 together once the epoxy is cured. It is preferable to have the epoxy 16 fill the entire space between the sidewalls 14 , as shown in FIG. 4 , to prevent any trapped, condensed moisture from entering the package. In addition, the epoxy protects the sidewalls 14 and prevents the inorganic coating 15 from peeling off. The sealant material between the ends 18 of sidewalls 14 and the surface of substrate 10 , as shown in FIG. 4 , is preferably as thin as possible, for example, less than 1 um.
During the cure process of the epoxy glue, solvents in the glue will outgas and may disperse towards the area of the moving mirrors. Therefore it is beneficial that there be as little direct exposure as possible of epoxy material 16 to the mirror devices. In this embodiment of the invention, as shown in FIG. 4 , only the thin layer of epoxy between the ends 18 of sidewalls 14 and substrate 10 is directly exposed to the mirror devices. The epoxy 16 between the sidewalls 14 will be prevented by the sidewalls from entering the area 24 inside sidewalls where the mirrors 11 are located.
In the embodiment of the invention shown in FIGS. 5 and 6 , mechanical barriers 26 are placed on substrate 10 in the area where the inner sidewall 20 and outer sidewall 22 will contact the substrate 10 during the sealing process. If the sidewalls are to be bonded to the glass cover 12 instead of to the substrate 10 , these mechanical barriers will be formed on the glass cover 12 instead of on the substrate 10 . These barriers are placed on the substrate 10 prior to attaching substrate 10 to cover 12 to prevent the gasses from the epoxy material from reaching the area where the mirrors 11 are located. The seal under the outer sidewall 22 is to prevent these gasses from reaching neighboring devices on the same wafer. FIG. 6 shows the package after sealing.
In the embodiment of the invention shown in FIGS. 7 and 8 , instead of barrier 26 , shown in FIGS. 5 and 6 , a recess or cavity 30 is formed in substrate 10 in the area between the places where outer sidewall 22 and inner sidewall 20 will contact the substrate 10 during the sealing process. FIG. 8 shows the package after sealing.
Recess 30 can have, for example, a depth equal to the desired thickness of the epoxy glue layer between the ends 18 of sidewalls 14 and substrate 10 , for example, less than about 1 um. These cavities prevent the gasses from the epoxy material 16 from reaching the area 24 where the mirrors are located and from reaching neighboring devices on the same wafer.
The advantages of the package described in various embodiments include that it is moisture-resistant, it provides a sealed cavity which contains the ASC, it can be sealed under atmospheric conditions and it does not require a plug. The described package is readily manufacturable and achieves a moisture barrier, preferably by using composite materials. In addition, the package has a large gap between translucent cover and micromirrors that provides wider process tolerances and has greater tolerance of defects.
The process of manufacturing the package of the invention has fewer process steps and is capable of high throughput manufacture with far less manual handling than, for example, is required with processes using plugs. Furthermore, the described process prevents harmful materials from the epoxy from outgassing during the sealing process and entering the area containing the micromirrors where it can cause damage. | Apparatus and method of making an improved moisture-resistant package for a MEMS device having movable parts, the package including a substrate, a translucent cover over the substrate, a seal and moisture barrier and a plurality of parallel sidewalls around the periphery of the substrate and cover. The sidewalls have ends and an area between the sidewalls, and the sidewalls separate the substrate and cover by a sufficient distance to provide clearance for the movement of the movable parts. The package is sealed using a glue layer that at least partially fills the area between the sidewalls, and lies between the ends of the sidewalls and one of the substrate or cover. The glue layer causes the substrate or cover, respectively, to adhere to the ends of the sidewalls. The glue layer and the sidewalls together prevent moisture from entering the package. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of International Application No. PCT/US2012/068284 filed Dec. 6, 2012 which claims the benefit of U.S. Provisional Patent Application No. 61/567,511 filed Dec. 6, 2011.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of fine structures characterized by magnetic resonance and to a method for processing magnetic resonance signals.
2. Prior Art
U.S. Pat. No. 7,932,720 describes a method for measurement of biologic textures too fine to be resolved by conventional magnetic resonance imaging, providing a quantitative measure of the characteristic spatial wavelengths of these textures. In its simplest form the method consists of acquiring finely-sampled spatially-encoded magnetic resonance echoes along an axis of a selectively-excited inner-volume positioned within the biologic tissue to be analyzed. Signal analysis yields spectra of textural wavelengths within various sub-regions along the spatially encoded axis of the selected tissue volume.
Filtering techniques have been used in the prior art to selectively analyze sub-regions (regions of interest) by windowing within the selectively excited internal volume but they are non-linear as the method involves taking the magnitude of the signal to produce a signal intensity as a function of location. This prior art method (U.S. Pat. No. 7,932,720) describes a method wherein the basic steps are as follows:
1. Subject the sample to a magnetic field; 2. Subject the sample to magnetic resonance excitation; 3. Receive an echo signal from the sample while the sample is subjected to a magnetic field gradient; 4. Fourier transform the echoes and take the magnitude to convert them into a signal intensity versus position, 5. Select a region of interest by multiplying the transformed data by a windowing function; 6. Fourier transform again, converting back into the echo domain; 7. Display the result as the magnitude of the resulting derived spectrum treating it as a measure of frequency content.
While the approach in the '720 patent provides insight into underlying structure, particularly for biological samples, it is limited due to being non-linear and restricted to the use of the nonlinear magnitude function and two Fourier transforms.
Other prior art methods based on magnetic resonance for analyzing fine textures are similar to that of the '720 patent in that they also are nonlinear as a result of taking the magnitude to generate a signal intensity vs. location. They differ from the '720 patent in that they are based on the analysis of magnetic resonance image data rather than a one dimensional signal intensity. In general the steps used by these methods are as follows:
1. Receive a multiplicity of echoes (as a result of a 2D or 3D magnetic resonance acquisition sequence), 2. Fourier transform and then take the magnitude of the echoes to convert them into a signal intensity versus position (i.e., create an image or a set of images), 3. Select a region of interest by multiplying the transformed data by a windowing function (wherein the shape and the width have been carefully chosen to optimize the signal extraction without introducing truncation artifacts, and to minimize the decrease in spectral resolution), 4. Use a Fourier or other transform again to convert back into the echo domain which is a measure of frequency content, 5. Display the result as the magnitude of the resulting derived spectra.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an example of a magnetic resonance technique for selectively exciting an internal volume and imposing a one dimensional spatial encode along r. A sub-region of the selectively excited internal volume is indicated by ROI (region of interest).
FIG. 2 shows an approach described in U.S. Pat. No. 7,932,720 to generate a window function based upon an identified Region of Interest (ROI).
FIG. 3 shows a linear method utilizing two Fourier transformations and a complex multiplication to localize the signal to a region of interest.
FIG. 4 shows a Linear method utilizing convolution for filtering an echo signal to localize the signal to a region of interest.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention is based on the fact that the magnetic resonance echo signal from a one dimensional frequency encoded excitation is nominally the one dimensional Fourier transform of the structure. Furthermore the one dimensional Fourier transform of the structure is the distribution (spectrum) of spatial frequencies and phases contained in the structure.
The current invention method initially proceeds like that of the '720 patent, namely by:
1. Subject the sample to a magnetic field; 2. Subject the sample to magnetic resonance excitation; 3. Receive an echo signal from the sample while the sample is subjected to a magnetic field gradient;
However, the current invention although similar to the prior art described in the '720 patent differs in a key and significant way in that the invented method uses only linear signal processes to generate spatial frequency spectra from samples of structure. Taking the magnitude of a complex signal is a non-linear operation, which loses information and introduces artifacts. To avoid these effects, the current invention utilizes a linear set of signal processing steps, which provides significant advantages including the ability to readily calculate noise statistics and an opportunity to further optimize signal to noise. Linear signal processing methods are an improvement over the prior art for a number of reasons including:
Preserving the Gaussian distribution of the noise component of the echo signal, which facilitates subsequent quantitative analysis in terms of signal-to-noise, as well as providing a basis for quantitative statistical confidence measurements. Linearity preserves the underlying signal's complex structure, particularly in the phase space, where position is encoded. In contrast, non-linear processes, particularly magnitude operations, discard useful phase information. Non-linear analyses can introduce artifacts in the resulting dataset which were not present in the original dataset. In contrast, linear approaches do not. Through the use of linear transforms, the dataset can be projected into a so-called Transform Domain which can facilitate further analysis and feature identification. These, in turn, can provide direction as to how to best extract signals of interest from the original echo.
In general, the noise received as part of the MR acquisition can be well modeled as complex-valued Additive White Gaussian Noise.
As part of the MR acquisition process, an echo e[k] sequence of K samples, k=1, 2, . . . , K−1, K from MR is frequently modeled as
e[k]=s[k]+n[k]
where s[k] represents the k th sample value of the signal, and n[k] represents the k th sample value of the noise received as part of the MR acquisition process. Both the signal and noise sample values are complex-values. The complex-valued nature can be made more explicit as
e r [k]+je i [k ]=( s r [k]+js i [k] )+( n r [k]+jn i [k] )
where the subscript ‘r’ indicates the “real” component”, the subscript ‘i’ indicates the imaginary component, and ‘j’ is the imaginary number √{square root over (−1)}.
The noise samples are well-modeled as having a Gaussian distribution which are independent, identically distributed, and with zero mean. More specifically, the so-called probability density function of the noise term can be expressed as
p ( n ) = 1 σ 2 π e - 1 2 ( n / σ ) 2
where σ represents the standard deviation, for any noise sample n r [k] or n i [k], independent of k. Further, the independence of the individual noise terms means that the value of any one of the noise samples has no influence on any of the other noise sample values.
All of this can be described more concisely in a multivariate probability density function as
p ( n ) = 1 ( 2 π σ 2 ) K e - ( n T n ) / 2 σ 2
where n is a 2K dimensional vector (K real values, K imaginary values).
If then e[k] is subjected to a linear filtering process, the resulting noise distribution is modified, but it remains Gaussian distributed. It can be shown that the resulting multivariate probability density function can be now expressed as
p
(
n
)
=
1
(
2
π
)
K
∑
e
-
1
2
(
n
T
∑
-
1
n
)
Where now Σ represents the covariance matrix, and |Σ| represents its determinant.
The value of Σ can be calculated with knowledge of the linear filter, and the variance σ 2 of the input noise process. Alternatively, Σ can be estimated, using a variety of well-established estimation algorithms. Note too that the noise distribution is independent of the signal. In other words, aside from shifting the mean of the noise to the value of the signal, the input noise variance and the linear filter determine the noise covariance; it is not affected by the signal.
The importance of being able to derive the statistics of the noise contribution is a key factor in the use of linear filtering processes, because from these, it is relatively straightforward to quantify post-processing signal-to-noise, error-bars, confidence intervals, and the like. This facilitates the use of structural spectrum analysis in a quantitative sense, which is particularly relevant for e.g. medical applications.
Finally, while it may be possible to admit certain non-linear processing steps, in addition to contending with the potential distortion of the signal itself due to the non-linearity, an additional challenge is presented in the derivation of the resulting noise distribution, and its associated dependence on the underlying signal. While there are closed-form solutions of the resulting noise distribution for some “simple” non-linear processes, they are almost always dependent upon the underlying signal in some non-trivial manner. In general, noise distributions that result from a non-linear process are frequently intractable and cannot be easily expressed in a closed-form solution.
FIG. 1 illustrates one method of performing a selective inner volume excitation and spatial encode which produces and echo from the entire inner volume. The inner volume is defined by the intersection of the two slice selective excitations and the bandwidth of the MRI scanner receiver. The Region of Interest (ROI) in this case is a segment of the inner volume which is relevant for the analysis.
FIG. 2 illustrates one method for identifying a Region of Interest (ROI) from a one dimensional plot of the signal intensity along the selectively excited internal volume (r) and then calculating a window function to filter the echo signal so that the resultant echo contains spatial frequencies exclusively from the ROI. Window functions can be generated in other ways including simply by specifying a value of “r” and window width along the selectively excited inner volume.
FIG. 3 illustrates one method which can be used to select a specific ROI using a previously derived window function. The complex echo is converted to a generally complex-valued one dimensional profile using the Fourier Transform. The profile ROI is then selected by multiplying it by the previously derived window function. The resulting sequence is then extended in length by prepending and appending a sequence of zeroes which is used to eliminate wrap-around artifacts associated with circular convolution and to provide a “smoother” spectral representation. The resulting sequence is then converted to a generally complex-valued one-dimensional spectrum using the Inverse Fourier Transform.
FIG. 4 illustrates another method which can also be used to select a specific ROI using a previously derived window function. In this case, the calculated window function is converted to an equivalent impulse response using zero padding followed by a Fourier Transform. The impulse response is then applied to the complex echo either directly using a complex linear convolution, or indirectly through the use of a linear filter whose impulse response is as specified.
In the above illustrations, the Fourier Transform is used as a means to convert between the echo domain and an associated Transform domain, which in this specific example nominally corresponds to the spatial distribution of the material under study. Then a “Region of Interest” is selected in that Transform domain, then the resulting spectrum is extracted.
However, both the Transform, and indeed the selection of a “Region of Interest” within that transform space, is not limited to just the selection of a subset of a region of the Fourier Transform of the echo.
In actuality, any invertible linear transformation can be used as a means to project the echo into a corresponding transform domain. An equivalent Region of Interest within that transform domain can be selected (i.e. windowed), and the residual transformed back into the echo domain, which in turn can be interpreted as the spectrum of the underlying physical representation.
Some commonly used invertible transforms include various so-called Wavelet Transforms, or z-Transforms.
The use of transforms can be useful, not only in terms of physical localization, but also for noise reduction as well.
The present invention is applicable to the assessment of any anatomical structure, whether of hard or soft tissue. Thus the present invention has a number of aspects, which aspects may be practiced alone or in various combinations or sub-combinations, as desired. While a preferred embodiment of the present invention has been disclosed and described herein for purposes of illustration and not for purposes of limitation, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the full breadth of the following claims. | A method of assessing a spatial frequency distribution within a sample comprising subjecting the sample to magnetic resonance excitation, receiving an echo signal from the sample while the sample is subjected to a magnetic field gradient, applying an invertible linear transform to the echo signal, identifying a region of interest in the transformed echo signal and deriving a corresponding window function, applying the window function (in the signal or transform domain) to the echo signal to remove echo signal coming from regions of the sample outside of the region of interest, and analyzing the one dimensional spatial frequency content in the windowed echo signal in order to access a one dimensional spatial frequency distribution within the region of interest within the sample without creating an image. | 6 |
This application is a continuation of application Ser. No. 07/911,480, filed on Jul. 10, 1992, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an information retrieval apparatus, and in particular to an information retrieval apparatus with artificial reality (AR) where the user can select and hold capsule images that a three-dimensional image display unit displays in a three-dimensional image space with his hands so as to collate and retrieve information from a database.
2. Description of the Related Art
In this age of information, flooding, there is a great need for quickly and accurately retrieving desired information. Thus, the importance of an operation for readily retrieving a great amount of information is increasing.
Input and output (I/O) interfaces such as a keyboard, a touch panel, and a mouse for use in the conventional information retrieval apparatuses are used to input keywords and the like. With keywords being input, information is collated and retrieved in the forms of images and hard copies. Thus, thus far, only users who are accustomed to the operations of the keyboard and familiar with the relevant database system can retrieve desired information by operating the keyboard and so forth of the terminal units.
On the other hand, in the recent computer simulation field, user-friendly computer interfaces which ingeniously utilize human beings' motions and their five senses such as sight and hearing have been developed and studied. These interfaces are referred to as artificial reality.
At the present time, the artificial reality can be divided into two major categories. One is referred to as virtual reality in which a "user agent" who is an agent of the user of the interface is displayed in computer graphics images. The user can experience a world which is spread out in the computer graphics images through the "user agent."
The other category is referred to as tele-existence in which the user can operate a robot at a remote position as his agent through a manipulator. While the tele-existence focuses on operations under the real environment, the virtual reality focuses on the use of the "user agent" as an interface of the computer itself.
As an example of computer simulation tools for accomplishing the above mentioned virtual reality, a three-dimensional display unit and data gloves have been developed. The former three-dimensional display unit provides for a three-dimensional computer graphics world. A variety of three-dimensional display units have been proposed by U.S. Pat. Nos. 4,881,068, 4,853,769, 4,834,476, 4,160,973, and so forth. In the virtual reality, some three-dimensional display units utilize a mechanism where the motions of the user's hands do not intercept the images being displayed so that he can feel that he is directly handling three-dimensional images with his hands. For example, "Eyephone" which was developed by NASA and produced by VPL Research Company (United States) is a three-dimensional display unit which is in a ski goggle shape and has an LCD display device inside thereof.
On the other hand, the data gloves are input interfaces for inputting the motions of the user's hands into a computer. The data gloves are provided with magnetic sensors and optical fiber cables over the surface thereof. Thus, the user can detect and recognize the positions and motion patterns of his hands and input particular information into the computer.
As was described above, the conventional information retrieval apparatuses with a conventional keyboard and so forth were not user friendly. Even if they were user friendly, they could not be effectively operated. In addition, since retrieved information was displayed on a flat display such as a CRT (cathode ray tube) monitor, the user could not straightforwardly recognize the weighting of retrieval indexes. Further, with the flat display, another display method for displaying a plurality of screens at a time, that is, a multi-window could be used. However, as the amount of information increased, since the display screens were overlapped, the visibility deteriorated, and the correlations between each information of retrieval indexes could not be effectively displayed.
On the other hand, the virtual reality was used as a simulation tool of computer graphics. However, thus far, the virtual reality has not yet been used for designating media directly accessing a database stored in a computer with the data gloves and for performing set logical operations.
An object of the present invention is to solve the above mentioned problems involved in the related art and to provide an information retrieval apparatus with which the user can select media as indexes allocated as images in the image space with his hands, issue predetermined commands, and straightforwardly retrieve information from a database.
SUMMARY OF THE INVENTION
The present invention relates to an information retrieval apparatus, and in particular to an information retrieval apparatus with artificial reality (AR) where the user can select and hold capsule images that a three-dimensional image display unit displays in a three-dimensional image space with his hands so as to collate and retrieve information from a database.
An object of the present invention is to solve the above mentioned problems involved in the related art and to provide an information retrieval apparatus with which the user can select media as indexes allocated as images in the image space with his hands, issue predetermined commands, and straightforwardly retrieve information from a database.
The present invention in one aspect thereof provides an information retrieval apparatus, comprising a three-dimensional display unit for displaying a set of indexes controlling attributes of a database in a three-dimensional image space in the sight of a user with index display images so as to allow the user to visually recognize the set of indexes, an input unit for detecting a motion pattern of the user's body against the index display images as input information and for displaying the motion patterns in the three-dimensional image space, and an arithmetic operation unit for recognizing the input information of the motion patterns received through the input unit and for performing set operations of indexes displayed with predetermined index display images so as to collate and retrieve information from the database.
The present invention in another aspect thereof provides an information retrieval apparatus, comprising a three-dimensional display unit for displaying a set of indexes controlling attributes of a database in a three-dimensional image space in the sight of a user with index display images and for allowing the user to visually recognize the set of indexes with operation capsule images, an input unit for detecting motion patterns of the user's body against the index display images and the operation capsule images as input information and for displaying the motion patterns in the three-dimensional image space, and an arithmetic operation unit for recognizing the input information of the motion patterns received through the input unit and for performing set operations of indexes displayed with predetermined index display images by using a logical operation means represented with the arithmetic operation capsule images so as to collate and retrieve information from the database.
The present invention in a further aspect thereof provides an information retrieval apparatus, comprising a two-dimensional display unit for displaying a set of indexes controlling attributes of a database in a two-dimensional image space in the sight of a user with index display images so as to allow the user to visually recognize the set of indexes, an input unit for detecting motion patterns of the user's body against the index display images as input information and for displaying the motion patterns in the two-dimensional image space, and an arithmetic operation unit for recognizing the input information of the motion patterns received through the input unit and for performing set operations of indexes displayed with predetermined index display images so as to collate and retrieve information from the database.
The present invention is an information retrieval apparatus, comprising a display unit for displaying a set of indexes controlling attributes of a database with index display images, an input means for inputting input information for causing predetermined index display images displayed on the display unit to perform predetermined motion patterns, and an arithmetic operation unit for recognizing input information through the input means and for performing set operations of indexes displayed with the index display images so as to collate and retrieve information from the database.
According to the present invention, the user can directly operate index display images in a three-dimensional image space or a two-dimensional image space without the necessity of a keyboard and recognize input information with his body's motion patterns. An arithmetic operation unit performs set logical operations of indexes displayed with predetermined index display images so as to retrieve and collate desired information from a database. Thus, even if the user does not have enough experience in operating the conventional input and output units such as a keyboard, he can readily and accurately retrieve desired objects from an information medium such as a database.
In addition, since a set of indexes for use in collating and retrieving information are displayed as index display images in the three-dimensional image space or the two-dimensional image space, the user can clearly and visually recognize the indexes for use in retrieving information, thereby making the information retrieval operation easy.
Further, since a variety of motion patterns of the user corresponding to index display images have been defined as particular input information, the retrieval apparatus can perform predetermined operations in accordance with the motion patterns. Thus, the user can readily select and discard indexes for use in retrieving information by using the input information. For example, by holding and flipping any index display image, the user can delete the corresponding retrieval index. By moving the index display image inwardly, the user can obtain the retrieval index.
Furthermore, index display images are displayed on the display unit. When input information for causing an index display image to perform a predetermined operation pattern is input through the display unit and set logical operations of indexes are performed by an arithmetic operation unit, information can be collated and retrieved from the database.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of the present invention will become more apparent in the light of the following detailed description of best mode embodiments thereof, as illustrated in the accompanying drawings, wherein
FIG. 1 is a schematic diagram virtually showing the relation between an embodiment of a three-dimensional image space displayed by an information retrieval apparatus in accordance with the present invention and a user thereof;
FIG. 2 is a schematic diagram conceptually showing a three-dimensional image space displayed by the information retrieval apparatus of FIG. 1;
FIG. 3 is a schematic diagram showing an example of a motion pattern of the user's hand;
FIG. 4 is a schematic diagram showing an example of a motion pattern of the user's hand;
FIG. 5 is a schematic diagram showing an example of a motion pattern of the user's hand;
FIGS. 6(a) and 6(b) are schematic diagrams showing examples of lotion patterns of the user's hand;
FIG. 7 is a schematic diagram showing an example of a motion pattern of the user's hand;
FIG. 8 is a schematic diagram conceptually showing time coordinate axis T in a three-dimensional image space;
FIG. 9 is a schematic diagram conceptually showing time coordinate axis T in a three-dimensional image space;
FIGS. 10 (a), 10 (b), and 10 (c) are schematic diagrams conceptually showing time coordinate axis T in a three-dimensional image space;
FIG. 11 is a schematic diagram hierarchically showing an example of the conception of an encyclopedia retrieval system of an embodiment of the present invention;
FIGS. 12(a), 12(b) and (c) are schematic diagrams showing information retrieval sequences of the encyclopedia retrieval system of FIG. 11;
FIGS. 13 (a), 13 (b) and 13 (c) are schematic diagrams showing the information retrieval sequences of the encyclopedia retrieval system of FIG. 11;
FIGS. 14 (a) and 14 (b) are schematic diagrams showing information retrieval sequences for the content of the retrieval result of FIG. 13 (c) by using the time coordinate axis T;
FIGS. 15 (a) and 15 (b) are schematic diagrams showing an example of a set logical operation;
FIG. 16 is a schematic diagram showing an example of a set logical operation;
FIG. 17 is a schematic diagram showing an example of a word and phrase search operation in accordance with another embodiment of the present invention;
FIG. 18 is a schematic diagram showing a character describing operation in a three-dimensional image space in accordance with another embodiment of the present invention;
FIG. 19 is a schematic diagram showing a pressure stimulating mechanism build in a data glove;
FIG. 20 is a schematic diagram showing a private eye that the user wears on his face; and
FIG. 21 is a schematic diagram showing a flat display screen which displays capsule images,
FIG. 22 is a schematic diagram showing another display screen which displays capsule images.
DESCRIPTION OF PREFERRED EMBODIMENTS
An embodiment of the information retrieval apparatus of the present invention will now be described in accordance with a practical information collation and retrieval sequence.
FIG. 1 is a schematic diagram virtually showing the relation between an embodiment of a three-dimensional image space displayed by an information retrieval apparatus in accordance with the present invention and a user thereof from a third person's point of view. In the figure, reference numeral 90 is a user who retrieves information from a database using the information retrieval apparatus of the present invention, The user 90 wears a three-dimensional display unit 91 in a ski goggle shape on his face. In addition, the user is fitted with (wears) data gloves 92R and 92L on his two hands. The data gloves 92R and 92L are an example of an input unit. The data gloves 92R and 92L have signal lines 93R and 93L, respectively. The signal lines 93R and 93L are connected to an arithmetic operation unit 94. The arithmetic operation unit 94 generates particular input information data or process commands by using motion patterns of the user 90 which are detected through the data gloves 92R and 92L. In addition, the arithmetic operation unit 94 sends to the signal lines 95R and 95L signals for feeding back motions of the user 90 which are detected by the data gloves 92R and 92L and motions of capsule images in the three-dimensional image space. A retrieval arithmetic operation unit 96 is connected to a database 101 whose attributes are controlled with indexes. As shown in FIG. 2, the three-dimensional display unit 91 displays the motions of the data gloves 92R and 92L as virtual arms 8R and 8L in the image space so as to form a world of artificial reality in which the virtual arms 8R and 8L can handle a variety of capsule images 4, 5, and 6 displayed in the image space. In other words, before the eyes of the user 90, a three-dimensional image space as shown in FIG. 2 is displayed.
In the three-dimensional image space, the user 90 holds a capsule image 4g with his right hand data glove R and attempts to flip a capsule image 4c with his left hand data glove 92L. In this case, an image where the virtual right hand 8R attempts to hold the capsule image 4g and the virtual left hand 8L attempts to flip the capsule image 4C is displayed before the eyes of the user 90.
In FIG. 1, reference numeral 7 is a storage area. The storage area 7 has the shape of a box. The storage area 7 can accommodate a variety of capsules.
Next, the situation of the three-dimensional image space displayed before the eyes of the user 90 will be described in detail.
In FIG. 2, a frame 2 virtually represents an outline of a three-dimensional image space in which information is displayed. The three-dimensional image space is set in the range where the virtual arms 8R and 8L of the user 90, who wears the data gloves 92R and 92L on his hands, can amply reach. In the three-dimensional image space, capsule images shaped like rectangular cards 3a, 3b, 3c, 3d, and 3e; capsule images shaped like barrels 4a, 4b, 4c, 4d, 4e, 4f, and 4g; capsule images shaped like oblate spheres 5a, 5b, 5c, 5d, 6a, 6b, 6c, 6d, 6e, and 6f; and spherical capsule images 7a and 7b are displayed.
For example, the rectangular shaped capsule images shaped like rectangular cards 3a, 3b, 3c, 3d, and 3e represent a set of retrieval indexes of small personal information such as a directory. The retrieval indexes are sorted outwardly in the alphabetical order. The same level capsule images 4a, 4b, 4c, and 4g are displayed in the same depth. The next level capsule images 4d and 4e are displayed in a deeper position than the capsule images 4a, 4b, 4c, and 4g. The further lower level capsule image 4f is displayed in a further deeper position than the capsule image 4d and 4e. Likewise, the capsule images shaped like oblate spheres 5a, 5b, 5c, 5d, 6a, 6b, 6c, 6d, 6e, and 6f are weighted in accordance with the importance of the information or retrieval indexes. The spherical capsule images 7a and 7b displayed at the right end of the frame 2 can be used as process capsules representing the selection method and the storage area of information such as logical operations. The capsule images 3a, 3b, . . . , 6e, 6f, which represent a set of indexes, are index display images. On the other hand, the capsule images 7a and 7b, which represent arithmetic operation information, are arithmetic operation capsules.
The retrieval indexes represent indexes for use in collating and retrieving information from the database 101. Generally, the retrieval indexes are referred to as keywords, key items, and so forth. The retrieval indexes are constructed of attributes retrieved from information stored in the database 101. Thus, in the database retrieval, by collating the retrieval indexes with the information indexes, a set of required information can be extracted. At that point, by linking a plurality of retrieval indexes by using logical operations, more accurate information can be obtained. Thus, proper retrieval indexes should be readily selected. In addition, logical operations should be performed without restrictions. To satisfy these conditions, the information retrieval apparatus according to the present invention performs this retrieval operations by using the above mentioned capsule images.
With reference to FIG. 2, the selection operation of retrieval indexes by using the capsule images 3, 4, 5, 6, . . . , and so forth will now be described.
In FIG. 2, reference numeral 8R is the right hand of the virtual arms. As shown in FIG. 1, the virtual arm 8R is a virtual image which can perform the same motion patterns as the real hand of the user such as moving in a three-dimensional image space, opening and closing the hand by input information. FIG. 2 shows the situation where the thumb and the index finger of the right hand 8R of the virtual arms 8 hold the capsule image 4g. By a motion pattern against the capsule image 4g, a retrieval index for a set logical operation shown by the capsule image 4g in accordance with a motion pattern thereof is selected.
In this embodiment, a holding motion was exemplified. However, as input motions, a capsule image can be held by the entire right hand 8R of the virtual arms or lightly touched by any finger of the right hand 8R.
In addition, according to this embodiment, when the user holds the capsule image 4g with the right hand 8R, he can recognize the status of the information being selected with a changed color of the capsule image 4g, a selection acceptance sound, or a flashing light. Thus, the user 90 can readily sort retrieval indexes and have a caution and a warning to an incorrect operation with a sound and a light.
Moreover, when the user 90 holds the capsule image 4g with the virtual right hand 8R, he can have a pressure on his real right hand. In other words, as shown in FIG. 19, the data glove 92R is provided with a pressure exerting mechanism 105. The pressure exerting mechanism 105 is activated in accordance with information being input from the real right hand of the user 90 to the data glove 92R.
For example, when the arithmetic operation unit 94 receives input information from the data glove 92R and determines that the virtual right hand 8R holds the capsule image 4g, the pressure exterting mechanism 105 of the data glove 92R is activated and an actual pressure is transferred to the real right hand of the user 90. Thus, the user 90 can positively have a "holding" sense.
As a practical example of the pressure exerting mechanism 105, a method where a force applied to each finger is detected by a respective distortion gauge and converted into an air pressure applied to a respective inner balloon can be used.
Moreover, in this embodiment, when the size of any capsule is changed depending on the amount of information of a relevant retrieval index, the user 90 can instantly and visually determine the size of the information.
On the other hand, the left hand 8L of the virtual arms shown in FIG. 1 represents the state wherein the index finger attempts to flip the capsule image 4c. With this motion, the user 90 can delete the capsule image 4c out of the screen. In this example, a practical flipping motion was shown. However, when the user 90 attempts to delete any capsule image, he can use the back of any finger to flip any capsule image or hold the capsule image and throw it out of the frame 2.
Further, like keywords, the contents of the above mentioned retrieval indexes can be displayed on capsule images. The information displayed with keywords can be retrieved. In this case, for example, by holding two capsule images representing keywords with the fingers one after the other, information relevant to the two keywords can be immediately displayed. This information retrieval method is particularly effective in the event that the user 90 attempts to retrieve complicated information relevant to a plurality of keywords.
With reference to FIGS. 3 to 7, an example of motion patterns of the hands recognized by the data glove 92 will now be described.
Generally, the hands of the human beings can perform several motions such as holding, picking, flipping, selecting, and moving objects. By using capsule images as objects, set logical operations for retrieval indexes displayed with capsule images can be performed in accordance with a variety of motion patterns, and arithmetic operation commands for the retrieval indexes can be input to the arithmetic operation unit.
Next, definitions of motion patterns of the hands will be exemplified.
FIG. 3 is a schematic diagram showing a "gripping" motion for gripping the capsule image 4 with the palm of the virtual arm 8R. At that point, the coordinates of the position of the capsule image 4 are tracked by the computer. The state where the virtual arm 8R grips the capsule image 4 is recognized when the coordinates of capsule image 4 (A), the coordinates of sensor (B) disposed at the end of the index finger, and the coordinates of sensor (C) disposed at the end of the thumb are aligned in the sequence of (A)-(B)-(C). At this point, in the embodiment, the retrieval index of the capsule image 4 gripped within the palm is extracted for collating and retrieving information.
FIG. 4 is a schematic diagram showing a "holding" motion. When the distance between the sensor disposed at the end of the index finger and that of the thumb is less than a predetermined value and a capsule image of a keyword is present between these sensors, the state for holding the capsule image is recognized. Alternatively, by processing a three-dimensional image, it can be recognized.
FIG. 5 is a schematic diagram showing a "flipping" motion. When the motion speed or the velocity of the finger tip detected by the relevant sensor disposed at the end of the index finger exceeds a predetermined value and the index finger interferes with any capsule image, the state wherein the retrieval index of the capsule image is deleted is recognized.
FIGS. 6 (a) and 6 (b) are schematic diagrams showing a "selecting" motion. In FIG. 6 (a), when the sensors disposed at the finger tips of the four fingers approach each other and a virtual line (A)-(B) interferes with any capsule image, the state wherein the retrieval index of the capsule image is moved is recognized. In addition, as shown in FIG. 6 (b), any capsule images can be selected from those surrounded by both hands.
FIG. 7 shows an example of a set logical operation. In the figure, when the right hand 8R holds the capsule image 4 and the left hand 8L holds the capsule image 5, the state wherein the AND operation of both retrieval indexes is performed is recognized. At this point, when the right hand 8R picks (holds) the capsule image 4 which is a set of retrieval indexes to be retrieved (or a plurality of capsule images), a predetermined logical operation for the retrieval index of the right hand 8R can be executed.
For example, when the right hand 8R holds the capsule image 4 and the left hand 8L holds the capsule image 5, the "OR" operation of the index of the capsule image 4 and the index of the capsule image 5 can be performed. Alternatively, under the assumption that the operation capsule image 7a represents an "AND" logical operation means, when the user 90 contacts or overlaps the capsule images 4 and 5 held by the right hand 8R with the operation capsule image 7a held by the left hand 8L one after the other, the "AND" operation of the indexes of the image capsules 4 and 5 can be "performed".
In addition, particular hand motion patterns such as for stopping a process during retrieval execution can be defined. In this case, by designating unusual hand motions, incorrect motions can be prevented.
In the above mentioned motion patterns, the use of the data gloves was exemplified. However, it should be appreciated that any input unit which can keep track of hand motion patterns can be used regardless of what construction the input unit has. Moreover, it should be understandable that besides the eyephone, any three-dimensional display unit can be used.
Next, an effective retrieval method in the case where retrieval indexes of capsule images contain time factors will be described.
FIG. 8 shows a linear time coordinate axis T displayed in a three-dimensional image space. In the figure, the capsule image 4 is displayed in such a way that it floats along the time coordinate axis T. Since the capsule image 4 contains a time factor as a retrieval index, data corresponding to the time coordinate axis T at which the capsule image 4 is present can be retrieved from the relevant database. For example, when the capsule image 4 is present at a position of June, 1990 on the time coordinate axis T, only data with respect to June, 1990 is extracted from data which is hit with the retrieval index of the capsule image 4. In the case where the user 90 wants to obtain data with a particular range of the time factor of this capsule image, when he intercepts the time coordinate axis T with both the hands 8R and 8L of the virtual arms as shown in FIG. 9, the range (from T1 to T2) can be designated. Thus, for example, data in the range from June, 1989 to December, 1990 can be extracted as the time factor of the relevant capsule image from the database.
However, on this linear time coordinate axis T, the depth of the axis is linearly proportional to the elapse of years. Thus, when the user 90 retrieves data which relates to old years of the time coordinate axis T, he would have difficulty in moving his hands.
To overcome this drawback, as shown in FIG. 10 (a), by arranging the time coordinate axis T in a spiral shape, the direction of depth of the image space can be effectively used. In this case, the time steps of the time coordinate axis T can be varied in such a way that the old years are coarsely allocated. Thus, years can be effectively allocated on the time coordinate axis T. In FIG. 10 (a), when the user 90 holds the capsule image 4 with his left hand 8L, he can move the capsule image 4 along the time coordinate axis T. In addition, for example, by drawing a circle several times with the left hand 8L, the user 90 can move the capsule image 4 along the time coordinate axis T. Further, as shown in FIG. 10 (b), the time coordinate axis T can be formed in a zigzag shape. Furthermore, as shown in FIG. 10 (c), the time coordinate axis T can be formed in a snaky shape.
As described above, according to the present invention, since the user 90 can straightforwardly select desired information from a plurality of capsule images displayed in a three-dimensional image space with his hands, the present invention can be applied to a variety of information retrieval systems which are currently available such as encyclopedia information retrieval systems, newspaper information retrieval systems, baseball information retrieval systems, patent information retrieval systems, historical information retrieval systems, map information retrieval systems, medical information retrieval systems, telephone directories, company organization information retrieval system, and personal information retrieval systems.
Next, with reference to FIG. 11, a practical information retrieval method of an encyclopedia information retrieval system will be described.
FIG. 11 is a schematic diagram conceptually showing a retrieval method in which the user hierarchically selects a desired conception from a large category to a small category.
First, capsule images 11a, 11b, and 11c which are in level 1 as large category information are displayed in the above mentioned three-dimensional image space. At this point, the user 90 will directly hold the capsule image 11b representing "history" which is the desired information from the capsule images 11a, 11b, and 11c in the above mentioned manner. Then, the present screen will be changed and capsule images 13a, 13b, and 13c which are in level 2 will be displayed. At this point, the user 90 will select the capsule image 13b representing "region" which is the desired information in the same manner as at the level 1 from the capsule images 13a, 13b, and 13c. Then, the present screen will be changed as in the level transition from the level 1 to the level 2. Then, capsule images 15a, 15b, and 15c which are in level 3 will be displayed. At this point, the user 90 will select the capsule image 15b representing "Europe" from the capsule images 15a, 15b, and 15c. Likewise, the present screen will be changed. Then, capsule images 16a, 16b, and 16c in level 4 will be displayed. At this point, when the user 90 selects the capsule image 16b representing "Germany" which is the desired information, the present screen will be changed and a capsule image representing for example "medieval ages" as a selection item of Germany historical information will be displayed. Thus, by selecting these capsule images one after the other, the user 90 can obtain the desired information. This operation for selecting retrieval indexes can be executed in a very short period of time.
In the above described retrieval method, the screen of each level was changed one after the other. However, it should be understandable that capsule images can be selected in other ways. Although the level 1, which is the largest category, should be selected first because it is the base position of the information retrieval operation, the display sequence of capsule images of the level 2 or lower levels is not limited. For example, in any of the following three manners, the user 90 can reach the desired conception.
Sequence 1: History →region →Europe →German →ages →medieval ages -→religion
Sequence 2: History →ages →medieval ages →region →Europe →German →religion
Sequence 3: History →religion →region →Europe →ages →medieval ages
Thus, capsule images in a plurality of levels (for example level 2 or lower levels) can be displayed at a time as shown in FIG. 11. Alternatively, by grouping capsule images through a plurality of selection screens, those in the level 1 only or those in the level 2 only can be displayed.
Next, with reference to FIGS. 12 and 13, an operation method that the user 90 can use will be described in detail.
In these figures, the retrieval is sequence represented with STEP 1 to STEP 6. In accordance with these steps, the operation method will be described. STEP 1:
The user 90 will select a capsule image representing the desired conception from capsule images in the level 1, which is the largest category. These capsule images are displayed in such a way that they are floating in the three-dimensional image space. Then, the user 90 will select and hold a desired capsule image representing the conception to be retrieved with, for example, the left hand 8L. Thereafter, the user 90 will move the capsule image held with the left hand 8L to a storage area 7 disposed on the right of the three-dimensional image space (see FIG. 12 (a)).
STEP 2:
The user 90 will select and hold a capsule image representing the desired conception from capsule images in the level 2 with his left hand 8L. Thereafter, the user 90 will move the capsule image held by the left hand 8L to the storage area 7 (see FIG. 12 (b)).
STEP 3:
The user 90 will select and hold a capsule image representing the desired conception from capsule images in the level 3 with his left hand 8L. Thereafter, the user 90 will move the capsule image held with the left hand 8L to the storage area 7 (see FIG. 12 (c)).
STEP 4:
The user 90 will select and hold a capsule image representing the desired conception from capsule images in the level 4 with his left hand 8L. Thereafter, the user 90 will move the capsule image held with the left hand 8L to the storage area 7 (see FIG. 13 (a)).
STEP 5:
The user 90 will select and hold a capsule image representing the desired conception from capsule images in the level 5 with his left hand 8L. Thereafter, the user 90 will move the capsule image held with the left hand 8L to the storage area 7 (see FIG. 13 (b)).
STEP 6:
Next, the user 90 will flip unnecessary capsule images out of the storage area 7 with the left hand 8L (see FIG. 13 (c)). Thereafter, the user 90 will move the remaining capsule image from the storage area 7 to a desired year (age) position on the time coordinate axis T newly displayed (see FIG. 14 (a)). In FIG. 13 (c), the reason why the user 90 flips the unnecessary capsule images out of the storage area 7 is to clearly and readily perform the subsequent retrieval operations.
When the user needs the information with respect to the medieval ages, he will place the selected capsule image in the position of year 1000 (see FIG. 14 (a)). When the user 90 needs the information in the range from years 500 to 1500, he will place the left hand 8L at the position of year 500 and the right hand 8R at the position of year 1500 to designate the range of years (see FIG. 14 (b)). When years on the time coordinate axis T are designated, the relevant historical events can be displayed in predetermined output formats. Thus, the sequence of retrieval operation is completed.
When the user 90 needs to designate a range of years on the time coordinate axis T, he will retrieve information through three-dimensional image spaces being changed one after the other. To complete the retrieval operation, the user 90 can perform predetermined operations as the sign, such as turning the hand(s), pushing a particular capsule image, or holding a capsule image representing "END."
The above description focused on the retrieval operation of historical events. Further, for example, in the case for retrieving the evolutionary process of creatures, if the time coordinate axis T is present from the right to the left in the display space, when the user 90 extends the left hand to the left and the right hand to the right, he can retrieve information in the past and in the future (predictable information). Moreover, in the case where the time coordinate axis T is set in the direction of depth of the display space, when the operator 60 performs hand motions such as moving the hand(s) inwardly or outwardly, he can straightforwardly and readily retrieve information with respect to time factors along the time coordinate axis T.
In the case where information to be retrieved does not contain time factors, a "coefficient of importance" can be applied to the time coordinate axis T so as to display weighted information in accordance with the positions along the time coordinate axis T. In the case where there are several sets of relevant information, when the user 90 holds particular information, the relevant information can be redisplayed. Thus, even if a great amount of information is handled, the user 90 can straightforwardly handle it without confusion.
Next, with reference to FIGS. 15 and 16, a retrieval method for selecting information with set logical operations by using capsule images in the same level will be described.
FIG. 15 (a) shows the case where the user 90 will select a capsule image 50 representing for example "United States" in the same situation of the STEP 4, move the capsule image 50 to a storage area 51, and select and move a capsule image 53 representing "Japan" and a capsule image 52 representing "Germany" to the storage area 51. Thereafter, as in the STEP 6 in FIG. 13 (c), the user 90 will flip unnecessary images out of the storage area 51 in the same manner as in the STEP 6 shown in FIG. 13 (c) so as to display the three capsule images which are the capsule image 50 representing "United States", the capsule image 53 representing "Japan", and the capsule image 52 representing "Germany."
Thereafter, as shown in FIG. 15 (b), the user 90 will hold the capsule image 53 representing "Japan" and the capsule image 52 representing "Germany" with the right hand 8R and then contact the two capsule images 52 and 53 against each other. This motion represents an AND operation of the two capsule images 52 and 53. Thus, information in common with the two capsule images 52 and 53 can be retrieved in the subsequent step. In addition, when the user 90 holds the two capsule images 52 and 53 in contact with each other with the right hand 8R and the capsule image 50 representing "United States" with the left hand 8L, the OR operation of the capsule images held with the left and right hands 8L and 8R can be represented. In other words the situation shown in FIG. 15 (b) represents a motion for retrieving a set of information in common with the capsule image 53 representing "Japan" and the capsule image 52 representing "Germany" and information of the capsule image 50 representing "United States".
Of course, it is possible to define the motion for contacting the capsule images 52 and 53 against each other as an OR operation and the motion for holding the capsule image 50 as an AND operation.
Thus, by two types of motions for holding a plurality of capsule images at a time, an AND operation and an OR operation can be simply represented and a set of information to be retrieved can be readily designated and changed.
Next, with reference to FIG. 16, a retrieval motion of an exclusive OR operation will be described.
In the case where the user 90 will select capsule images representing "creatures", "plants", and "flowers" in this sequence and place them in a storage area, he will select a capsule image representing "trees" from "plants" and place the selected capsule image in the storage area. Thereafter, the user 90 will pick a capsule image 61 representing "flowers" from the storage area with the left hand 8L and pick a capsule image 63 representing "trees" with the right hand 8R. Thereafter, the user 90 will contact the capsule image 63 representing "trees" against the capsule image 61 representing "flowers" and then separate them. This motion represents an exclusive OR operation. In other words, this motion represents "flowers" which do not blossom on "trees" or "trees" which do not flower. In addition, a negation can be represented by a motion for holding a capsule image and then turning it. Thus, according to this embodiment, by natural motions of human beings such as contacting capsule images against each other, separating them, and turning them, the user 90 can retrieve information.
FIG. 17 is a schematic diagram showing a retrieval method in accordance with another embodiment of the present invention.
In the figure, a dictionary 70 with words alphabetically arranged is displayed in a three-dimensional image space. When the user 90 consults the dictionary 70, he can scroll screens by touching the surface of the dictionary 70, which is an image, with the hand 8R or 8L and leaf through the pages thereof. In this case, the user can scroll the screens by knocking the left hand 8L and the right hand 8R. When there is a hit of word, phrase or topic, the user 90 can pick up an icon representing the word, phrase, or topic from the dictionary 70 so as to directly retrieve the object.
Since every word and every phrase of each page of the dictionary 70 has an embedded icon 72, the icon 72 can function as an index of information like a capsule image. Thus, when dictionaries in a variety of categories are provided and information is retrieved in this way, since it is not necessary for the user 90 to carry heavy dictionaries, he will not be fatigued from the information retrieval operation.
FIG. 18 shows a means for newly inputting a keyword which is not represented by a capsule image. An input means 80 has a shape of a pen 81 which is displayed in a space. The user 90 can hold the pen 81 with the virtual arm 8R or 8L. When the user 90 properly holds the pen 81, ink will discharge and thereby the user 90 can write characters in the space. When the user 90 attempts to create new keywords, relevant indexes for controlling attributes of the database should have been already provided.
As described above, by utilizing the feature whereby characters and/or geometrics images can be written and/or drawn in the space, the information retrieval apparatus of the present invention can be used as a teaching tool for children. In this case, the present invention can provide most people from children to aged people with interfaces to the computer graphics world.
In addition, when a keyboard that any user likes is displayed in the space and the user can input data from a unit which detects the above described hand (finger) motions, the user can select a favorite one from a variety of keyboards of different standards for use in inputting data. Thus, according to the present invention, the user can retrieve information by conventional keyboard operations that he is accustomed to.
In FIG. 1, an example wherein the motion patterns of the user's hands were detected by the data gloves 92R and 92L that he wears on his two hands and the motion patterns were used as input information was described. However, it should be understood that besides the motion patterns of the user's hands, the motion patterns of the user's head 110 can be detected by a head band 112 which supports the three-dimensional display unit 91. Further, the motion patterns of the user's feet can be detected.
Furthermore, the motion patterns of the user's hands or the user's head can be detected by a TV camera 100 and the detected information can be sent to the arithmetic operation unit 94.
In FIG. 1, an example wherein a three-dimensional image space is displayed before the eyes of the user 90 by the three-dimensional display unit 91 having ski goggle shape that the user 90 wears was described. However, as shown in FIG. 20, the user can wear a private-eye 114 at a position slightly away from the head 110 and see a three-dimensional image space displayed from the private-eye 114. When the private-eye 114 is used, the sense of oppression against the head 110 can be decreased. In addition, the shapes of capsule images displayed in the three-dimensional image spaces can be freely designated in accordance with their meaning and contents.
In FIGS. 1 and 2, an example where a three-dimensional image space was displayed by the three-dimensional display unit 91 that the user 90 wears was described. However, instead of the three-dimensional display unit 91, the user can wear a two-dimensional display unit 116 for displaying two-dimensional image spaces. When the user 90 wears the two-dimensional display unit 116, the virtual left hand 8L, the virtual right hand 8R, and the various capsule images 3, 4, 5, 6, and 7 are displayed in the two-dimensional image spaces.
With reference to FIG. 21, another embodiment of the information retrieval apparatus in accordance with the present invention will be described. In the figure, capsule images (index display images) are displayed on a flat display screen (display unit) 121 such as a CRT display unit. These capsule images 124, 125, and 126 represent a set of indexes for controlling attributes of a database.
When the user contacts a touch pen 141 held in a real right hand 140 against the capsule images 124, 125, and 126 displayed on the screen 121, information for performing predetermined operation patterns can be input to the capsule images 124, 125, and 126. For example, when the user contacts the capsule image 125 with the touch pen 141 and moves the touch pen 141 to the position of the capsule image 124, the capsule images 125 and 124 can be superimposed.
In other words, the flat display screen 121 is connected to the arithmetic operation unit 130. The arithmetic operation unit 130 recognizes information which is input from the touch pen 141 and displays the motions of the capsule images on the screen 121. In addition, the arithmetic operation unit 130 performs set operations of indexes displayed with the capsule images 124, 125, and 126 in accordance with the information being input from the touch pen 141. The computed result of the arithmetic operation unit 130 is sent to the retrieval operation unit 131. The retrieval operation unit 131 inputs retrieval data into the database 132.
In FIG. 21, when the user moves the capsule image 125 to the position of the capsule image 124 and superimposes them together, an AND operation of the capsule images 124 and 125 Us represented. Thus, the arithmetic operation unit 130 can perform the AND operation of the capsule images 124 and 125. Thus, the user can retrieve information in common with each index displayed with the capsule images 124 and 125 from the database 132.
Next still another embodiment of the information retrieval apparatus in accordance with the present invention will be described with reference to FIG. 22.
In FIG. 22, parts which correspond to parts shown in FIG. 21 are depicted by the same reference numerals, and detailed descripitions of them are omitted.
As shown in FIG. 22, a righthand mouse 144 having a cord 144a is held by the real right hand 140, and the righthand mouse 144 is slid on an operation plate (not shown) so that information for performing predetermined operation patterns can be input to a capsule image 148. A lefthanded mouse 146 having a cord 146a is held by a real left hand 142, and the lefthand mouse 146 is slid on the operation plate so that information for performing predetermined operation patterns can be input to a capsule image 150. In this way, for example, two capsule images 148 and 150 can be superimposed.
In this case, the cord 144a of the righthand mouse 144 and the cord 146a of the lefthand mouse 146 are connected to the arithmetic operation unit 130. The arithmetic operation unit 130 recognizes information which is input from the righthand mouse 144 and the lefthand mouse 146 and displays the motions of the capsule images 148 and 150 on the screen 121. In addition, the arithmetic operation unit 130 performs set operations of indexes displayed with the capsule images 148 and 150 in accordance with information input from the righthand mouse 144 and the lefthand mouse 146. The computed result of the arithmetic operation unit 130 is sent to the retrieval operation unit 131. | An information retrieval apparatus features a three-dimensional display unit for displaying a set of indexes controlling attributes of a database in a three-dimensional image space in sight of a user with index display images so as to allow the user to visually recognize the set of indexes. An input unit detects motion patterns of the user's body against the index display images as input information and displays the motion patterns in the three-dimensional image space. An arithmetic operation unit recognizes the input information of the motion patterns received through the input unit and performs set logical operations of selected images in accordance with the motion patterns so as to collate and retrieve information from the database. The user can further directly operate index display images in a three-dimensional image space or a two-dimensional image space without the necessity of a keyboard and recognize input information with his body's motion patterns. The arithmetic operation unit performs set logical operations of indexes displayed with predetermined index display images so as to retrieve desired information from a database. Thus, even if the user does not have enough experience in operating conventional input and output units, such as a keyboard, he can readily and accurately retrieve desired objects from a medium such as a database. | 6 |
[0001] This application is a continuation of U.S. patent application Ser. No. 10/323,230, filed Dec. 18, 2002 (Attorney Docket No. AOL0028).
FILED OF THE INVENTION
[0002] The invention relates to computer security. More particularly, the invention relates to a trusted communication channel to combat user name/password theft.
BACKGROUND OF THE INVENTION
[0003] Discussion of the Prior Art
[0004] Malicious individuals employ various schemes to steal user name and password pairs from real users in the computer system. A common scenario for such theft is to “spoof” an official page of a system and lure a user into entering a user name and password into the system. The attacker then logs in and changes the compromised password to preclude use thereof by the true user, and ensure completion of the theft. In some cases, the attacker must immediately use the stolen password, for example where there is a time sensitive component, such as a Secure ID component.
[0005] FIG. 1 is a schematic flow diagram that shows a user 10 logged in to a system 12 (as indicated by numeric designator ( 1 )). A malicious individual 18 generates a message 14 , for example indicating to the user 10 that they might win a corporate incentive and that details with regard to the incentive are provided at a website, e.g. “go to xyz.” The message is provided to the user 10 as indicated on FIG. 1 by the numeric designator ( 2 ).
[0006] The user follows the link, as indicated on FIG. 1 by the numeric designator ( 3 ). At the end of the link, there is a page 16 which the user had been lead to believe is within the company system, i.e. which is a trusted page, but which is in fact an outside, i.e. untrusted, page. The user is asked to type in the user name and/or password to verify that they are entitled to receive the reward promised at the site. Unwittingly, the user enters this information and the malicious individual is thereafter able to capture the user's name and password, as indicated on FIG. 1 by the numeric designator ( 4 ). Thereafter, the malicious individual can log into the system, change the user's password, and steal information from the account. This is indicated on FIG. 1 by the numeric designator ( 5 ).
[0007] It would be advantageous to provide a technique for using a trusted communication channel to combat user name/password theft.
SUMMARY OF THE INVENTION
[0008] The invention provides a technique for defining a system with enhanced trust. In one embodiment of the invention, an immediate contact is made with the user on the enhanced trust system when a compromise is first detected, e.g. when there is a second log in attempt from another location. Using trusted communications channels, the service can often contact the compromised user and ask for confirmation of the results, i.e. to change password or login, from a reduced trust machine. As a result, even if an attacker steals a password, the true user on the enhanced trust machine is able to preclude a login or preclude a password change. In each case, if the user of the enhanced trust machine does not respond within some short period of time, then a less trusted machine can be allowed to proceed.
[0009] The invention comprehends an enhanced trust machine, which is a machine where the user is currently logged in at the time that the second, less trusted machine attempts a login.
BRIEF DESCRIPTION OF THE FIGURES
[0010] FIG. 1 is a schematic flow diagram showing a technique that is used to “spoof” a user name and password;
[0011] FIG. 2 is a flow diagram showing a technique for using enhanced trust to combat user name and password theft according to a first embodiment of the invention; and
[0012] FIG. 3 is a flow diagram showing a system for using enhanced trust to combat user name and password theft according to a second embodiment of invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] In general, for security, there are three classes of identification;
What you have; What you know; and What you are.
[0017] Examples of the first item include possession of a specific piece of hardware; the second item is exemplified by a password; and the third item is a biometric indicator, such as fingerprint or voiceprint. The invention operates with the assumption that a machine that is used extensively by a user is tagged as a machine that has enhanced trust. For example, if a user comes to their workstation everyday and uses the same machine, then the system develops experience with regard to the user's work patterns and expects that that machine is used by the user. Thus, the trust of the user being at that machine is enhanced. In the preferred embodiment of the invention, this is done by recording the number of times the given user has logged in from a given machine, and storing evidence of that history locally, possibly signed by a service to preclude forgery. At a minimum, the fact that a machine has a current active login assures that the machine is relatively more trusted than a machine that has neither a current, nor prior login by a given user. Specifically, the invention tags machines to create an additional “what you have” to add to the current password “what you know.” Modern authentication theory suggests that two out of these three classes of identification are needed for significant assurance of identity. The invention recognizes this aspect of security theory and uses the concept of tagging and verification to prevent forged authentication, such as stolen passwords.
[0018] It is difficult, if not almost impossible, to prevent spoofing of official pages, for example where innocent victims are lured into supplying user names and passwords. One aspect of the invention uses the provisions of online services, such as AOL's AIM service, to make an immediate machine-to-human connection to the most likely valid user. The fact that many companies use a time-varying password generation scheme, such as secure ID, to generate a random number as a function of the time and day, provides assurance that an attacker must immediately use a compromised password. However, the invention is also useful in other password generation schemes. Because most passwords are comprised while the users are still online, the invention takes advantage of the fact that it is possible to reach the online user.
[0019] With credit cards, charges that are exceptional in nature often induce a credit card agency to contact the person directly for additional authentication. In this invention, instant messaging technology is used as the contact mechanism. One embodiment of the invention uses current and prior login history to establish a pattern of actions, i.e. experience, and detects suspicious logins and password changes. The public key system commonly known as PGP (Pretty Good Privacy) uses a history of communications to establish a trust relationship with a person and the person's key. Thus, PGP includes the notion of basing trust on history. However, the invention herein recognizes that experiential information may be applied to password authentication and, when combined with machine tagging such as writing signed logs to a disk to identify a relative trust of a piece of hardware, that a ability to prevent spoofing of a system is provided. The result of this sort of defense almost completely precludes theft of internal passwords. It also gives the company employing such a system a rapid notification about such theft attempts, which can then be applied to attempt to blockade further efforts. For example, attempts to use stolen accounts from related blocks of IP addresses machines are then implicitly listed as being untrustworthy.
[0020] Thus, the invention comprises technology for defining a machine as being a machine having enhanced trust, wherein a messaging technology is used to make immediate contact with the user on the enhanced trust system. Using such communications channels, the invention provides a mechanism that can contact the compromised user and ask for confirmation for results, i.e. to change a password or even to login, with regard to a reduced trust machine. Thus, even if an attacker steals a password, the true user on the enhanced trust machine is able to preclude a login or preclude a password change. In each case, if the user on the enhanced trust machine does not respond within some short period of time, then a less trusted machine is allowed to proceed, should this be desired.
[0021] The invention presently comprises an enhanced trust machine, which is a machine where the user is currently logged in at the time a second, less trusted machine attempts a login.
[0022] FIG. 2 is a flow diagram of a preferred embodiment of the invention in which a user is logged into a system ( 100 ). If a second login attempt is made ( 102 ), then the system sends an Instant Message to the user logged in at the first, enhanced trust location ( 104 ) to verify that the second login is authorized ( 106 ). If the user of the enhanced trust machine confirms that the user of the less trusted machine is properly permitted to login, for example by retyping a password, or typing a special password, then the less trusted machine is allowed to login ( 110 ). Likewise, if there is a timeout, indicating that the user logged in at the initial machine is not responding, for example because they have walked away from the machine and are now walking to another location, then the user is typically allowed to login as well. If the user responds to the instant message that there is no permission or no desire to login at the second, less trusted machine, then second login is refused ( 108 ). In this case, the second machine may be added to a filter list which blocks the machine or gives rise to an investigation the machine as having a suspicious IP address ( 112 ).
[0023] FIG. 3 is a flow diagram which shows an alternative embodiment of the invention in which the concept of trust is based upon experience. In FIG. 3 , a user is logged in ( 100 ) when a second login attempt is made ( 102 ). In this case, the system looks to see if the user action is consistent with system experience ( 200 ). For example, the system may determine that the machine at which the user is currently logged in is one that the user has used everyday over a period of time and that is therefor a trusted machine, while the second login attempt is being made from a less trusted machine, i.e. a machine from which the user has never logged in before. It may be that the user is in fact logging in from the second machine legitimately. In such case, the mechanism outlined in connection with FIG. 2 above can be applied, in which the system sends an instant message to the user at the first login to verify that the second login should be permitted ( 104 ). Thereafter, the mechanism is applied as set forth, for example in FIG. 2 ( 204 ). If the user action is consistent with experience, then the second login is allowed ( 202 ).
[0024] The concept of experiential trust can be based upon one or more of many factors, including the use of a particular machine over time by a user, the use of the system by the user within a particular geographic region, i.e. the user has never logged in outside of the United States, the use of a particular machine at given times of day, i.e. the user has never attempted to login at 4:00 AM, or any other relevant factors. The forgoing situations are provided by way of example, and those skilled in the art will appreciate the various other bases for experience may be incorporated into this system. Furthermore, while the invention is described in connection with the use of an instant messaging mechanism for notifying a user of a trusted machine that there is an attempt to access the system using a less trusted machine, those skilled in the art will appreciate that the mechanism need not be instant messaging, but could involve the use of any other channel, such as a pager, a telephone, or other messaging systems. A key point is that the user of the trusted machine is notified promptly that an attempt is being made to login at a remote location. Further, while the invention is described as providing notification to the user at a trusted machine when an attempt is made to change a password or login identification from an untrusted machine, the system may tolerate the use of an untrusted machine so long as no attempt is made to change the password or user name. In such case, any attempt to change the password or user name requires the use of some further evidence of trustworthiness at the less trusted machine, for example the user would have to provide a further password that had previously been entered into the system but which has not been previously used as part of the current session. Absent this further proof, an instant message is sent to the user at the trusted machine and the mechanism herein described is invoked.
[0025] Although the invention is described herein with reference to the preferred embodiment, one skilled in the art will readily appreciate that other applications may be substituted for those set forth herein without departing from the spirit and scope of the present invention. Accordingly, the invention should only be limited by the claims included below. | A technique for defining a system with enhanced trust is disclosed, in which an immediate contact is made with the user on the enhanced trust system when a compromise is first detected. The service contacts the compromised user and asks for confirmation of the results. As a result, the true user on the enhanced trust machine is able to preclude a login or preclude a password change. In a first embodiment of the invention, an enhanced trust machine is a machine where the user is currently logged in at the time that the less trusted machine attempts a login. A second embodiment of the invention comprehends an enhanced trust machine where the user has logged in repeatedly over a course of numerous weeks, as compared with a lesser trusted machine that the user has never logged into before and which is now asking for a change of the password. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
Not Applicable
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not Applicable
BACKGROUND OF THE INVENTION
1. The Technical Field of the Invention
The disclosure generally relates to set of tools for food handling during grilling process and more specifically to the set of two tools where one is a fork and the other is a knife that work also as spatulas, and while both are interlocked together, they work as tongs, as a grill scraper, and grill grasper. Fork's body contains a can opener while knife's body contains juice can piercer and beer bottle opener, therefore together work as one multifunctional BBQ tool.
2. Description of Related Art
In one approach set of tools used for barbecue contains tongs, fork, hook, and spatula that may work as a knife. A set has also a bear bottle opener. Tongs, fork, spatula, and hook used separately or simultaneously with one other tool, require the other tools to store somewhere close by.
In another approach spatula alone works as fork or knife and often contains a beer opener. The problem with such approach is that a cook-operator still needs to use either tongs and separate fork or knife to manipulate a grilling food.
Yet another approach is to provide universal handles with exchangeable inserts that each performs a different function. The problem with such approach is that exchangeable parts have to be stored somewhere during food preparation so the parts may be easily misplaced. The other problem with such approach is that parts after initial use are not clean anymore and placing them back in the storage container or handling them afterward is not convenient.
Another approach is using the tongs of which one arm works as a knife and the other as a fork. The problem with such approach is that fork should be stationary during cutting with a knife so while the arms are not separable—additional tool is necessary.
Yet another approach is to separate both parts of tongs by utilizing spring loaded connection with oftentimes complex mechanism that lowers reliability of such tool.
Therefore, it is apparent that there is a need for a barbecue tool, which is cost-effective, easy to manufacture and store, and while used outside, to efficiently perform multiple and necessary functions, while also being compact enough to keep it in the usually limited storage space around BBQ.
BRIEF SUMMARY OF THE INVENTION
The present apparatus and methods described here in preferred embodiment meet the recognized need for basic barbecue tools in the form of knife and fork that each can work separately as spatula or, when interlocked together, can work as tongs. Cutouts placed in the foot sections allow resilient interlocking connection of both spatulas to function as tongs and allow hanging each tool separately or in one piece as tongs assembly. Sharp tools, namely a piercer and a can opener, are located away from contact with operator's hands ensuring safety of operation.
Patterns of knife-spatula and fork-spatula blank cuts from planar stainless steel sheet require additional operations such as sharpening edges, forming the cutouts of incorporated tools, bending, and connecting thermo-insulating material to become the finished product.
Tool grip of the handle contains two strips made from a thermo-insulating material in two different thicknesses: thin and thick, where thin strip is placed on the inner side of tool while a thick strip goes outside.
Stainless steel properties of knife and fork provide necessary resilience to operate tools assembled together as a tongs without any additional mechanism, added part, or process.
Cutting patterns integrated in the foot of tools allow forming can piercer in the knife and can opener in the fork. Sharp edges of the can opener and can piercer placed far from food handling parts stay clean unless being used accordingly. That way the sharp edges do not require the same amount of cleaning as the remaining parts of tools, lowering a chance of an unintentional injury to the operator. Foot ends of both knife and fork, usually directed towards the operator, are rounded to prevent injury from accidental piercing and ensure the tools' safe use. Lip-bend of fork foot provides a bearing for edge of circular shape of knife foot and allows alignment of the top edge of the knife-spatula with the bend of the fork-spatula tips for use as a scraper, where the top edge of the knife-spatula cleans the top of the grill, while bent tips of fork-spatula clean sides of the grill when knife-spatula and fork-spatula are assembled as tongs and are in closed position.
Tips of fork-spatula, bent towards working space, while assembled in tongs, provide additional gripping power during food handling, and while tongs are in closed position, lower a chance of accidental piercing by teeth of the fork and prevent unintentional cutting by sharp edges of the knife-spatula. Lateral teeth of fork-spatula, being wide and having tips bent, work as hooks for handling the food.
BRIEF DESCRIPTION OF THE DRAWINGS
Descriptions of drawings for the present and exemplary BBQ set of knife-spatula and fork-spatula provide a consistent reference with numerals denoting similar elements throughout, including details views and perspective views of fragments.
FIG. 1 is a dimetric view of the knife-spatula with indication of detail “A” of foot section;
FIG. 2 is a dimetric view of the fork-spatula with indication of detail “B” of foot section;
FIG. 3 is a dimetric view of detail “A” of knife-spatula foot section;
FIG. 4 is a dimetric view of detail “B” of fork-spatula foot section;
FIG. 5 is an illustration of the first step in a process of interlocking fork and knife spatulas to work together as a tongs;
FIG. 6 is an illustration of the second step in a process of interlocking fork and knife spatulas to work together as a tongs;
FIG. 7 is an illustration of knife-spatula interlocked with fork-spatula to work as a tongs;
FIG. 8 is a diametric view of the tongs from fork-spatula side indicating detail “C” and showing relative position of locking head of knife-spatula and fork lip of fork-spatula that is acting as a bearing;
FIG. 9 is a detail “C” of head sections in dimetric view from fork-spatula side of tongs;
FIG. 10 is a diametric view of tongs indicating detail “D” of grasper;
FIG. 11 is a dimetric view of detail “D” of grasper.
Drawings illustrate present and exemplary BBQ set of knife-spatula and fork-spatula to explain structural and convertible properties of disclosure.
DETAILED DESCRIPTION
Use of actual terminology to describe exemplary and preferable embodiment of the present disclosure as illustrated in FIGS. 1-11 does not exclude any or other technical terminology or limit processes or shapes to describe similar products, which may lead to accomplishment of similar shape, function or purpose, and to be limited only by listed claims.
Referring to FIG. 1 , elongated pattern cutout from the planar stainless steel sheet after being mechanically formed and processed to work as a knife that functions also as a spatula has three parts distinguished by shape, function, and purpose.
A head of a knife-spatula 1 has two lateral edges 5 that while sharpened work as left-handed and right-handed knives. Top edge 6 of knife-spatula works as a part of a scraper and oblong cutouts 7 work as a meat juicer. Transitional trapezoidal shape of the knife-spatula is a part of the head. Obtuse angles of bend 1 b and 1 a place spatula away from the body to create food-handling space and enhance scooping of grilled food. A handle works as a tool grip with a thin strip 3 of thermo-insulation material placed at the food handling side, and a thick strip 4 placed at the opposite side. A foot works as an interlocking device and as a pivot for fork-spatula 2 . A can piercer located below the handle on the side of the thick strip 4 is formed from the pattern cutout. The rounded foot works as a bottle opener and one part of the two-part grill grasper.
Referring to FIG. 2 , elongated pattern cutout from the planar stainless steel sheet, after being mechanically formed and processed to work as a fork that functions also as a spatula, has three parts distinguished by shape, function, and purpose.
A head of a fork-spatula 2 has multiple cutouts to form the shapes of teeth 8 and 9 along the top peripheral edge, where wide lateral teeth 9 are working as a hooks. Tips 10 of all fork teeth are bent not more than seven degrees in the direction of food handling side and provide better food grip without diminishing piercing ability of a fork and also work as a part of scraper.
Transitional trapezoidal shape of the fork-spatula is a part of the head. Obtuse angles of bend 2 b and 2 a move spatula away from the body to create food-handling space and enhance scooping of grilled food.
A handle works as a tool grip with a thin strip 3 of thermo-insulation material placed at the side of food handling, and a thick strip 4 placed at the opposite side. A foot works as an interlocking device and yoke for knife-spatula 1 . A can opener located below the handle on the side of the thick strip 4 is formed from the pattern cutout. The rounded foot of fork has projection-bend 19 and lip-bend 20 , and while bent in such way that lip-bend 20 is perpendicular to the foot and is offset by projection-bend 19 from the foot at the resulted distance, provide alignment for heads of knife-spatula 1 and fork-spatula 2 in the assembly of tongs used as a scraper.
FIG. 3 illustrates a view of detail “A” of knife-spatula 1 , where the circular end of the foot works as a locking circular shape 11 , while cutout inside the circular shape works as a bottle opener 12 . Shape of the cutout above the circular shape matches the yoke opening in fork-spatula 2 where locking neck 16 , locking edge 17 , and locking support edge 18 together function as a pivot. Can piercer is formed from the pattern of a can piercer cutout 13 located above the yoke and projecting on a side of the thick strip 4 . A can piercer sharp edge 14 is formed from an upper cutout shape, while a can piercer lip 15 is formed from lower cutout shape.
FIG. 4 illustrates a view of detail “B” of fork-spatula 2 , where the yoke at the foot section consists of two types of shapes: vertical aperture 24 that accommodates the size of locking circular shape 11 of knife-spatula 1 , and a rectangular cutout 26 that functions as a yoke. The length of the yoke horizontal edge 25 corresponds to the width of locking neck 16 in the foot of knife-spatula 1 . The pattern cutout 21 for can opener located in the fork-spatula 2 above the yoke provides upper cutout shape to form can opener sharp edge 22 and a lower cutout shape to form the can opener lip 23 , that work together as the can opener that is accessible from the side of the thick strip 4 of a handle. The rounded foot section of the fork-spatula 2 has two bends in the same direction as bends of can opener. The fork projection-bend 19 ensures the correct placement of the lip-bend 20 to work as a bearing for locking circular shape 11 of the knife spatula 1 in tongs assembly used as a scraper, and as a grasping face in a grasper illustrated in FIG. 11 .
The following figures illustrate the two step process of interlocking fork-spatula and knife-spatula to work as tongs, where:
FIG. 5 illustrates the first step when foot in circular shape 11 of knife-spatula 1 passes from the side of working space to the opposite side of the fork-spatula 2 through the elongated vertical aperture 24 . FIG. 6 illustrates the second step, where foot in circular shape 11 of knife-spatula 1 is clear on the other side of fork-spatula 2 , and locking neck 16 of knife-spatula 1 is turned in the rectangular cutout 26 of the fork-spatula 2 and ready to work as tongs utilizing resilient fixed connection between feet of fork and knife. FIG. 7 illustrates the tongs assembly in open position, where the interaction of fork lip-bend 20 of fork-spatula 2 and locking circular shape 11 of knife-spatula 1 ensures the relative position of both spatulas.
FIG. 8 illustrates the tongs assembly in closed position in a diametric view from the fork-spatula 2 side with an indication of the detail “C” and relative position of circular shape 11 of knife-spatula 1 and fork lip 20 of fork-spatula 2 at the foot. Tongs works as a scraper only while food-handling spaces of both tools face each other and are in closed position.
FIG. 9 illustrates the detail “C” of tongs assembly in diametric view from the fork-spatula 2 side, where bends of tips 10 of fork-spatula 2 are aligned with peripheral top edge 6 of knife-spatula 1 . Closed tongs works as a scraper, in which side edges of tips 10 clean sides of a grill and peripheral top edge 6 cleans top of a grill. Wide lateral teeth 9 work as hooks when fork-spatula 2 is used individually.
FIG. 10 illustrates the tongs assembly in diametric view in open position for use as a grasper with indication of the detail “D”.
FIG. 11 illustrates the detail “D” of tongs assembly used as a grasper, where: fork projection-bend 19 with fork lip-bend 20 grasps, and together with the circular shape 11 of knife-spatula 1 , holds an edge of a vessel, container, grill, or plate. Fork lip-bend 20 also guides the locking circular shape 11 and prevents misalignment of the knife-spatula 1 and fork-spatula 2 in tongs assembly.
The above embodiment of the invention of BBQ convertible tongs, in which the scope of the invention is described and illustrated hitherto, is determined by the appended claims. | Barbeque tools in the form of fork-spatula and knife-spatula work separately or as a tongs when interlocked together by cutout in the body of each tool that assures resilient hinged-like connection without use of spring, pinion, clasp or hinge, and allows using the closed tongs as a grill scraper at one end of tool, and grill or vessel grasper at the opposite end of tool, while bottle opener, can piercer, and can opener being integral parts of the spatulas and placed away from contact with operator's hands equally ensure a safe use of each spatula separately and while in tongs assembly. | 1 |
FIELD OF THE INVENTION
[0001] The present invention refers to a set of methods for managing networks (both logical and physical networks), within a number of areas. More particularly the present invention discloses a method for analyzing a network, where the network consists of any number of network nodes connected by links.
BACKGROUND OF THE INVENTION
[0002] Almost any social or physical structure where individual entities are linked together by some sort of relationship can be analyzed from a network perspective, be it social groups, airway routes, or groups of computers. Networks are interesting objects. They have a great deal of structure, and yet at the same time are simple: they consist, in simplest form, only of nodes, connected by links. The abstract idea of a network, or graph—the term is used interchangeably—is also highly useful in modelling structures observed in the real world. Examples include: social networks, communications networks, the World Wide Web, metabolic and genetic networks in biological systems, food webs, disease networks, and power networks. In short, a network is a simple, nontrivial abstract structure, fascinating in its own right, and also highly relevant for many branches of science and technology.
[0003] Within the area of telecommunications, theories regarding network management and network structures have been established for a long time. It is of crucial importance to understand a network. The efficiency of operation and maintenance of such a telecommunication network will largely rely on knowledge of the network in question. It is important both with respect to mean time between failure, as well as with respect to the spreading of damage, such as viruses, worms or the like.
[0004] For data communication networks the situation is much the same. Similar considerations are relevant for operation of electric power networks, particularly with respect to safety. Within planning and operation of electric network it is important to have a robust network, thus for example avoiding situations where a large part of a population is exposed to power outage. Analysis of the connectivity of a network is important for robustness considerations.
[0005] System administration invariably involves managing a network, which is composed of multiple types of links. Examples include: the physical links between the machines, the logical links between users and files, and the social links between users. An important aspect of system administration is to ensure the free flow of needed information over the network, while at the same time inhibiting the flow of harmful or damaging information, over this same network.
[0006] The structure of the network plays a crucial role in the implementing of these two important, and partly conflicting, goals of system administration. Both goals involve the spreading of information over links of the network; hence both problems are strongly sensitive to the network structure. Because of this dependence, the understanding of network structure can be a valuable component of effective system administration.
[0007] Furthermore, there are of course those networks that are both social and technological. Examples include telephony networks; peer-to-peer networks [10] overlaid on the Internet; and the combined network of computers, files, and users that is the daily preoccupation of every system administrator.
Here, once again, security seems an obvious application for these ideas: one wishes to identify nodes that should be given highest priority in protecting against viruses, for example.
[0009] Studies of networks have received a great deal of attention in the last decade or so. Most of the measures of network structure that have been studied to date [8] take the form of ‘whole-graph’ properties, that is, scalar measures or distributions which apply to the graph as a whole, and are calculated using averaging. Examples of such whole-graph properties include the node degree distribution, the diameter or average path length, clustering coefficients, and the notion of ‘small worlds’, which is based on the previous two.
[0010] Whole-graph properties are important and useful; however they cannot give a complete answer to the question, “How can we understand the structure of a network?”
[0011] There exist many examples where knowledge of networks, which take a more abstract form than those of telecom, datacom, or electrical networks, is of importance. For example, in the field of epidemiology, it is important to have an understanding of social networks and how these networks facilitate the spread of diseases. Within information distribution it is of importance to know the mechanisms governing the spreading of information within a population, be it on a local or global level.
[0012] When looking at inter human relationships or social networks one pays attention to the links between the individuals rather than their categories or what characterizes them. A social network is thus any group of persons where the individuals have some sort of relation to each other. Persons with a high degree of social influence in social networks are often labeled opinion leaders. They are influential either by virtue of their expertise or by virtue of their social position. In any case this influence often manifests itself by giving the opinion leaders a great number of social contacts; they are linked with a high number of people. This is of course logical; to have social influence means that you have the ability to reach a high number of people.
[0013] The utility of this idea for social networks seems clear [4]. It is also obviously of interest to identify communities in a measured social network. An example with a slightly different flavour is the network of sexual contacts. Here too these ideas may be quite useful, in work addressed at limiting the spread of sexually transmitted diseases: perhaps one would focus on the two complementary goals of (i) preventing infection of the central nodes of each community, and (ii) preventing the transmission of the disease across the bridging nodes.
[0014] For these reasons, networks merit serious study. A network is one of the simplest abstractions of structure that can be studied; yet, understanding the structure of a network is a nontrivial undertaking.
PRIOR ART
[0015] In the scientific field of network analysis, there are several ways to measure the centrality of network nodes. One of these measures is termed eigenvector centrality. Eigenvector centrality (EVC) was defined in the early seventies by Bonacich [2]. The basic idea behind EVC is, it's not only how many people you know, but also how important (central) they are, that determines how important (central) you are. This is thus actually a recursive definition: my importance (centrality) depends on my neighbors'—which in turn depends on mine. The point of such a recursive definition is to allow us to identify those hubs that are really influential from the perspective of the whole network. Otherwise a definition that counted importance only by how many neighbors you have would run the risk of nominating the centers of isolated clusters as network hubs. With respect to social networks these centers are only influential in a limited sense, since their influence does not extend beyond their immediate neighbors.
[0016] The work of Kleinberg [7], while addressed to networks with directed links, provides some useful perspective. Kleinberg considered a directed graph, defined two distinct types of roles for the nodes on the graph, and gave a way to calculate indices which quantify the degree to which each node plays the two types of role. That is, each node in a directed graph may be assigned an Authority score and a Hub score. It is important to note that these scores can be based solely on the topology of the graph-independent of any questions of content or meaning, or of any ‘properties’ of the nodes.
[0017] The names of these two role types convey their meaning. Nodes with high Authority are nodes which are important because they are pointed to by important nodes—in fact, by nodes with high Hub scores. And the latter obtain their high Hub scores by pointing to good Authority nodes. In short: Hubs point, and Authorities are pointed to. These ideas can be highly useful in analyzing the structure of the WWW: Authorities are likely good endpoints of an information search, while Hubs are useful in leading the search to the Authorities. It seems clear that similar roles arise in social networks: sometimes, one knows who has the needed information (the Authority); other times, one needs to ask a good Hub.
[0018] Kleinberg's work gives us indices for each node in the network. These indices tell us useful information about the role(s) the node plays in the network. Such information is quite distinct from whole-graph information; and yet it is still derived, at least as originally presented, purely from the topological structure of the graph.
[0019] Another aspect of a graph, which is again distinct from whole-graph properties, is the community structure of the graph. In the same paper, Kleinberg suggested a way to find such communities in graphs such as the Web graph. The mathematical tools used are basically the same as those used to find Hub/Authority scores—which means, among other things, that the decomposition of the graph into communities was also based purely on the structure of the graph, without invoking any knowledge or properties of the nodes or links. Furthermore, it can be noted that decomposing a graph into sub communities provides new information about the roles played by nodes: they may be members of community X; they may happen to lie in no community; they may be ‘leaders’ in some sense of their community, or they may lie on the ‘edge’; and they may play an important role in linking multiple communities.
[0020] Many other works have addressed the same problem of how to find ‘natural’ communities in a directed graph such as the Web. In contrast, Girvan and Newman [5] have looked at this question for undirected graphs. Their basic approach is to define communities by first finding their ‘boundaries’—specifically, by finding links with high ‘betweenness’, which, when removed, break the graph into sub communities.
SUMMARY OF THE INVENTION
[0021] It is an object of the present invention to provide a method for network analysis, to be applied either to physical networks, or to logical networks which exist as overlay networks on top of the physical network. The important common aspect is the identification of links (physical or logical), over which information can flow.
[0022] Another object of the present invention is to provide a ‘natural’ means—that is, one based solely on the graph topology—for decomposing an undirected graph into communities. A set of roles for the nodes of the graph will be defined, such that each node is assigned one, and only one, role. That is, unlike the approach of Kleinberg, for the present application it is desirable that the roles are binary (Yes/No) properties of nodes-and exclusive as well.
[0023] Prior art [13, 3] has shown in more detail how to apply the analysis presented here to networked computers with many users. The present invention provides a natural way of decomposing a network into well-connected clusters, and of assigning meaningful roles in information flow to each node in the network.
[0024] These objects are achieved in a method for network analysis as disclosed in the appended claim 1 . In particular, the present invention provides a method for analyzing the ability of a network to spread information or physical traffic, said network including a number of network nodes interconnected by links, said method including the steps of
mapping the topology of a network, computing a value for link strength between the nodes, computing an Eigenvector Centrality index for all nodes, based on said link strength values identifying nodes which are local maxima of the Eigenvector Centrality index as centre nodes, grouping the nodes into regions surrounding each identified centre node, assigning a role to each node from its position in a region, as centre nodes, region member nodes, border nodes, bridge nodes, dangler nodes, measuring the susceptibility of the network to spreading, based on the number of regions, their size, and how they are connected.
[0032] Advantageous embodiments of the invention appear from the following dependent claims.
BRIEF DESCRIPTION OF FIGURES
[0033] In order to make the invention more readily understandable, the invention will now be discussed in detail in reference to the accompanying figures, in which:
[0034] FIG. 1 is a schematic diagram showing a Bridge Node (left) and Bridge Node and Danglers (right).
[0035] FIG. 2 shows a simple graph with two regions.
[0036] FIG. 3 shows the same graph as in FIG. 2 , but with the regions defined using another rule. EVC values for the nodes are also shown.
[0037] FIGS. 4, 5 , and 6 show the resulting graphs of the MANA project [4] using three different measures for link strength.
[0038] FIG. 7 is a flow diagram illustrating the method used for calculating the Eigenvector Centrality index.
DETAILED DESCRIPTION OF THE INVENTION
[0039] Useful and interesting applications of ideas of network analysis are disclosed by the present invention. The only prerequisite is that the links of the networks are undirected. By undirected links we mean links that do not point in a specific direction. On the World Wide Web a web-page may point to another, but this page does not necessarily have to point back. In this instance the pages would be connected by a directed link. If both pages were hyper-linked to each other, one link going in each direction, these links could be collapsed into one, undirected link. The present invention treats all networks as consisting of undirected links.
[0040] The idea pursued by the present application is that ‘well-connectedness’ may be viewed as a height function over the discrete space (the graph). If the height function of the present invention is smooth enough, ideas appropriate for smooth surfaces over a continuous space can be employed. That is, the present invention will use a topographical picture to define regions in a network. Regions will correspond to ‘mountains’, with the centre of each region being the corresponding mountaintop. Boundaries between regions will then be defined as those points failing to be uniquely associated with one mountain region.
[0041] The defined roles are: ‘leader’ of a community (region); member of a community; and two types of roles for nodes in the ‘border set’, i.e., nodes not belonging to any community.
[0042] The approach taken is roughly dual to that of Girvan and Newman [5]. The present invention begins, not with the ‘edges’, but with the ‘centres’ of the communities. From this starting point, one works ‘outwards’ to find the members, and finally the border nodes. The presented set of roles is complete and consistent, in the sense that the definitions allow a unique and unambiguous association of a single role to each node in the graph.
EMBODIMENT OF THE PRESENT INVENTION
[0043] People that communicate with each other form a social network, where the links are based on their communication. These links may be distinguished according to the type of medium that is being used, be it telephony, face-to-face communications, or mail. Thus, the social network can be described as multiplex: it is a network where the nodes are related to each other by different types of links. Although the social relationships that link different persons together may exist independent of the type of medium used, the type of medium plays an important role in defining the links, as each medium is a distinct channel for information flow. Different communications media are in this sense analogous to languages. For example, a person that wants to reach many nodes in the network has to be able to communicate over multiple types of media—he has to speak the other nodes' preferred ‘language’. This idea of links differentiated by media is valid for most kinds of networks: Disease may for example spread through a number of different carriers of infections, and the links in transportation networks may consist of many different means for transportation, for example cars, planes, or trains.
[0000] Link Strength and EVC Measures
[0044] The strength of the links in this type of multiplex network can be determined in different ways. Here we mention four:
[0045] 1) One can simply state whether a link (of any type) exists or not. Numerically, one assigns 0 to ‘no link’ and 1 to ‘some link’.
[0046] 2) One can count the number of different media that connect any pair of nodes, that is, the number of different media that has any flow of substances or information between any two nodes in the network.
[0047] 3) One can measure the total flow between any two nodes in the network. To do this one must convert the data that is available to a common measure. This measure thus gives the net amount of flow (for example minutes or words for communications media) between any two nodes in the network.
[0048] 4) A fourth alternative is to determine the strength of the links through a mixture of 2) and 3). That is, count each medium [as in 2)], but weighted [as in 3)] by the fraction of flow for that medium, that a given pair uses.
[0049] The traditional way of determining link strengths is indicated as number 1). Method 3) is also known. Methods 2) and 4 are new and innovative methods for determination of link strengths.
[0050] The eigenvector centrality (EVC) index is mathematically defined as the principal eigenvector of a matrix. The simplest and most common method for finding the principal eigenvector of a matrix is the ‘Power Method’ [14]. This method involves repeated multiplication on a vector of weights by the matrix. Multiplication on the weight vector by the matrix is equivalent to what can be called ‘weight propagation’: it redistributes a set of weights according to a rule. Repeated redistribution of the weights (with overall normalization of the total weight) yields a steady distribution, which is the dominant or principal eigenvector. These are the scores, which are used as centrality index by the present invention.
[0051] For clarity, we illustrate the application of the Power Method, in FIG. 7 . Here, using the equations explained previously, the process starts and a start vector w 0 is chosen (S 401 ). At each iteration, a new weight w new is calculated (S 403 ) by redistributing the weights according to the action of the matrix operator. This new weight is then normalized (S 405 ). A convergence test is then performed (S 407 ). If the weight has converged, the process ends. Otherwise, a new weight is calculated and process repeats until the weight converges.
[0052] For the analysis of multiplex social networks, the EVC measure has been generalized to incorporate three other measures of link strength (2-4), as mentioned above. The modification of the general EVC idea, as applied in the new methods 2) and 4), is as follows: a node is central if it has many neighbors with high centrality—and uses many different types of media. In the following it is described how to implement this general idea for each of the four approaches to link strength discussed above:
[0053] 1) The traditional approach, in which the adjacency matrix A is composed only of 0's and 1's, could be used with multiplex networks; but it is totally insensitive to the number of media used by each pair of nodes.
[0054] 2) Here we simply replace the matrix A , whose entries are all either 0 or 1, with the matrix A color , defined as follows: the entry ( A color ) ij , is equal to the number of ‘colours’ (distinct media) connecting nodes i and j.
[0055] 3) Here the 1's in the traditional A matrix are replaced by a positive real number, giving the total volume of flow (summed over all media, and measured in a common unit of measure) over some given time interval. That is:
( A _ _ volume ) ij = ∑ c V c , ij ,
where c is an index ranging over ‘colours’ (media), and V c,ij is the total communications volume in medium c between nodes i and j.
[0056] 4) Finally the present invention proposes a mixture of approaches 2) and 3), so as to give weight both to flow volume and to the existence of multiple media. Hence, for each medium c and node pair ij, we give a ‘score’ which is the fraction (contributed by the pair ij) of the total communication that uses medium c in the network. Let V T,c denote the total volume (over the entire network) of communication using medium c. Then our ‘mixed’ measured of link strength may be written as
( A _ _ mixed ) ij = ∑ c ( V c , ij / V T , c ) .
[0057] The method according to the present invention converts flow data into an adjacency matrix, using one of the four methods described above to give each matrix entry a link strength measure. It then calculates the principal eigenvector of the resulting modified adjacency matrix. This allows us to assign an index (a positive number) to all the nodes in the network, giving their centrality according to one of our four measures. Those nodes with the highest centrality values are viewed as the most central nodes in the network. This allows the method to produce a list of the network hubs and their immediate neighborhoods. The centrality index also makes it possible to produce a topographical map of the network structure, that is, a graphical visualization of the network that shows the most central nodes as local ‘peaks’.
[0000] Roles in Networks
[0058] The final goal of the present invention is to assign a natural and unique role to each node in the network, based solely on the topology of the graph. As noted above, Kleinberg found two such roles for directed graphs: Hubs and Authorities. Hubs are naturally good at pointing to good Authorities; and Authorities are naturally good at being pointed to by good Hubs. One can see already from these simple grammatical statements that the distinction between Hubs and Authorities vanishes when the arcs of the graph become undirected (so that “pointing to”=“being pointed at”). The mathematics gives the same result: for the undirected case, the adjacency matrix is symmetric, A=A T , and so the matrices defining Hubs and Authorities become the same.
[0059] In short, for undirected graphs, the two types of roles collapse to one. That one role (more precisely, an index quantifying the degree to which the node plays the role) is eigenvector centrality.
[0060] The Hub operator AA T and the Authority operator A T A simply becomes A 2 , whose principal eigenvector is the same as that for A.
[0061] Hence it is found that two of the roles identified in Kleinberg's work with directed graphs becomes a single (type of) role for an undirected graph. This role type is called well-connectedness in the following sections, or eigenvector centrality. It is further searched for distinctions among the nodes of an undirected graph-in other words, multiple distinct roles, to which any given node may be assigned. These roles will be defined in the next section. Eigenvector centrality (EVC) will be the height function, and hence the starting point.
[0000] Definitions of the Roles
[0062] The difference between ‘role type’ and ‘role’ has to be clarified. Realvalued indices or ‘scores’ can be associated with each node: Hub and Authority scores for the directed case, and EVC score for the undirected case. These are role types; in fact it is fair to say that all three scores represent some type of centrality. All nodes have some degree of centrality; and ‘being central’ is certainly a type of role. By role however in this document it is meant a binary (yes/no) distinction applied to each node, so that each node receives a single Yes and hence is assigned a unique and unambiguous role. Centrality (a role type) will give a smooth height function over the graph, allowing the use of topographic criteria to assign a (Yes or No) role to each node.
[0000] Centres
[0063] For simplicity and readability the picture of mountains, valleys, saddles etc for the height function is kept. Each mountain may be defined by its peak. The peak is a local maximum of the height function. The first role is then the mountain peak.
[0064] Centre: any node which is a local maximum of the eigenvector centrality is a Centre.
[0000] Regions
[0065] Each mountain top defines a mountain. Hence the number of Regions in the graph is equal to the number of centres. (Henceforth, except when roles are defined, the capital letters is dropped; the meaning should be clear from context.) Regions are usually composed of more than one node; hence the role for a node cannot be a region, but rather a Region Member.
[0066] Region Member: each node that may be uniquely associated with a single Centre, according to an unambiguous rule, is a member of that Centre's Region, and hence a Region Member.
[0067] It remains to specify the “unambiguous rule”. According to the present invention, two possible choices are given for the “unambiguous rule”.
[0068] Rule 1 (distance). A node is associated with Centre C if it is closer (in number of shortest path hops) to C than to any other Centre C 0 .
[0069] Rule 2 (steepest ascent). For each node i, a steepest-ascent path starting at i will terminate at one (or more) Centres. If it terminates at a single Centre, then node i is associated with that Centre.
[0070] These rules are simply the discrete-domain version of the process of associating a part of the domain (base space) with each mountain top-hence defining each mountain. One must be careful here to break the definition of region into two parts: the definition itself, which refers to a rule but does not specify it; and the rule. This is done because more than one rule is possible for the discrete case; and the region definition in a way that captures the “mountain” idea is stated, but leaves the rule unspecified.
[0071] Both rules stated above satisfy the intuitively reasonable criterion that a centre's near neighbours should (in general) belong to its region. (It is, after all, the number and connectedness of a centre's neighbours that gives that centre its high EVC.) Both rules are also easy to implement in a simple iterative fashion-starting with the centres, and working outwards from them, “coloring” nodes according to the regions (centres) they belong to. The steepestascent rule is however the rule which is the most faithful to the topographic picture.
[0000] Borders—between Regions
[0072] On a continuous topographic surface there are points which lie between mountains, and belong to no unique mountain. It may happen that analogous points exist for the discrete case as well.
[0073] Nodes which cannot be associated with any one mountain are assigned to the Border set.
[0074] Border Nodes: any node for which the unambiguous rule for Region membership gives more than one answer is a Border Node.
[0075] Intuitively, one thinks of border nodes as “connecting regions”. And yet, a bit more thought reveals that not all border nodes are equal in this regard. Some border nodes do indeed play an important role in connecting two or more regions: they lie on paths which connect the respective centres (hence regions). See left panel of FIG. 1 . Other nodes may be removed, without any loss in the degree of connection between the regions. See right panel of FIG. 1 . Hence it is natural to define two distinct roles to the set of border nodes.
[0076] Bridge Node: a Border Node which lies on at least one nonself-retracing path connecting two Centres is a Bridge Node.
[0077] Dangler: any Border Node which is not a Bridge Node is a Dangler.
[0078] Danglers of course may inject new information into the network; but they do not play a significant role in the transport of information between regions.
[0079] Finally, it is desirable to single out a class of links which play an important role in connecting regions. The reason for doing so here is that the border set for the steepest-ascent rule is in general very small or zero. In this case it is still useful to highlight those network elements which connect the regions. Hence it is defined: Bridge Links: any link whose endpoints lie in two distinct Regions is a Bridge Link.
[0080] Bridge links will occur for either region rule above. One can imagine rules for defining regions which give ‘fat’ borders. For example, one could associate nodes with centres according to:
[0081] Rule 1′ (distance with cut-off). A node is associated with Centre C if it is closer (in number of hops) to C than to any other Centre C 0 , and if its distance from Cis not greater than h hops.
[0082] ‘Fat’ borders arise for such a rule since there could be many nodes which are farther than h hops from any centre. In general, ‘fat’ boundaries arise if one chooses a rule designed to avoid the ‘growing together’ of regions from their respective centres. Distance to which growth is allowed could then be measured in hops (as in Rule 1′), or in decrements in EVC.
[0083] Boundaries according to Rule 1 are ‘thin’: essentially one node wide. Boundaries according to Rule 2 are even thinner: in general, they are 0 nodes wide, since it is rare that a node will have two or more steepest-ascent paths, leading to different local maxima.
[0000] The Mathematics
[0084] The mathematical problems as solved by the present invention are solved focusing on ‘smooth’ functions over a discrete space.
[0085] Suppose the domain space is continuous. Then harmonic functions are the smoothest functions available. These functions are solutions to Laplace's equation,
∇ 2 φ=0 (1)
[0086] For a given space, one obtains different solutions to (1) from differing boundary conditions on φ.
[0087] One will immediately identify some problems with the continuum picture. One problem is that there are no maxima, or minima, away from the boundary. Hence the topographic picture according to the present invention cannot work with such smooth functions: every mountaintop will lie on the boundary. Furthermore, the present invention is disclosing a natural way of defining regions. Here “natural” means, guided as much as possible by the topology of the graph. Hence it is undesirable to have to assign values for the function φ at the boundary—it will be preferred that the topology solve this problem.
[0088] One can of course solve this last problem by setting φ=constant, for example, zero, at the boundary. That is, the boundary is just given some nominal reference value. This is “natural” enough; however one then get that φ=constant over the entire space, due to the averaging property of Laplace's equation.
[0089] The discrete version of Laplace's equation is
Lφ=0 (2)
where L=K−A is the Laplacian matrix, K=Diag(k 1 , k 2 . . . )is a diagonal matrix whose ith entry is the node degree k i , where k i is the number of connected neighbours of node i, and A is the adjacency matrix, with A ij =1 if there is a link from i to j, and 0 otherwise.
[0090] It is easy to see that the averaging property holds here also: solutions to (2) obey
ϕ i = 1 k i ∑ j = nn ( i ) ϕ j ( 3 )
[0091] Here “nn” means “near neighbour”. The discrete Laplace equation thus offers ‘most smooth’ functions for the discrete case; but it has all the problems seen for continuous harmonic functions, plus one more. The additional problem stems from the crucial fact that the specification of the boundary of a discrete space is not unique—in fact, there is no natural way to define such a boundary. One can of course take the, perhaps least arbitrary, assumption that none of the points are boundary points—all have to have their height determined by the graph structure—but then one gets back the constant φ i =constant.
[0000] Eigenvector Centrality
[0092] Following the discussion from the expression (3). A small change in the picture as given by (3) solves all of its problems at once. The small change is as follows: it is asked for a height function which obeys, instead of the averaging property (3), the following:
ϕ i = 1 λ ∑ j = nn ( i ) ϕ j ( 4 )
[0093] That is, instead of taking the strict average over all neighbours, one divides the neighbour sum by a constant λ, which is the same for all nodes. This equation can be written as
Aφ=λφ (5)
where A is again the adjacency matrix. Now we have an eigenvalue equation, and the height function φ is an eigenvector of the adjacency matrix. The present invention wants in fact the eigenvector which is the stable iterative solution of (4), because height is supposed to signify ‘well-connectedness’. That is, (4) encodes the idea that node i's well-connectedness is determined, to within a scale constant λ, by that of all of i's neighbours. Iterating this requirement, from any starting point, will give the principal eigenvector of the adjacency matrix. This eigenvector gives the stable, self consistent solution of (4); it also has the property that it is positive semi definite, since A is.
[0094] With this one modification, the problems as seen above with Laplace's equation (discrete or otherwise) are no longer present. EVC can have local maxima away from the boundary. In fact, since it measures well-connectedness, local maxima of EVC tend to lie well away from any nodes that one might be tempted to call ‘boundary nodes’. Furthermore, there is no need to define a boundary for the discrete case: all nodes may have EVC values determined by Equation (4), with no values input as ‘boundary conditions’.
[0095] Specifically, the contributions here are:
[0096] 1) The two new modified forms for the adjacency matrix, giving two new measures of centrality that allow network centers to be picked out.
[0097] 2) The definition and method for identifying network regions.
[0098] 3) The definitions and methods for assigning discrete network roles to each node in the network.
[0099] 4) Applying the new measures of centrality, regions, and roles to a wide variety of applications.
EXAMPLES
[0100] In the following is given examples of embodiment of the present invention as well as comparisons between the two rules for defining regions.
[0101] FIGS. 4, 5 , and 6 show the results of the MANA research project as presented in [4]. The graphs represent a small social network, a working group of 11 persons. With the use of the presented method's different measures for link strength, EVC-based centrality indices were made for the network. The topographical visualizations show the centrality of the nodes as differences in height. In FIG. 4 , link strength is measured based on the number of different media used by each node (method 2). FIG. 5 shows the graph when the link strength is based on the net amount of flow between the nodes (method 3). Finally, FIG. 6 shows the graph that is based on a mixture of the above methods for determining link strength, that is, both the number of media used and the net amount of flow (method 4).
[0102] FIG. 2 shows a simple graph with two centres. The Border consists of three nodes. One (node 11 ) is a bridge node which clearly plays an essential role in connecting the two regions, the other two are danglers.
[0103] Applying Rule 2 to the same graph gives us FIG. 3 . Here one can see that the entire border has been ‘swallowed’ by the dominant centre (node 9 ). The rather peripheral role of nodes 10 and 12 —formerly classified as danglers—is now reflected in their distance (2 hops) from their centre (and of course in their low EVC).
[0104] Comparing these two figures thus confirms the expectations about the differences between the two rules: a border set, with or without danglers, is typically present with Rule 1, but absent with Rule 2.
[0105] To illustrate the application of these ideas, we suppose that the nodes in FIGS. 2 and 3 are users in a computer network, while the links are effective connections between users which allow information flow. Here the term ‘effective’ connections is used, because the links may not be direct: they may be mediated by files to which both users have read and write access [3]. One can conclude immediately from the analysis that the user system is naturally composed of two main groups. Furthermore, node 9 is most central to the yellow group, while node 13 is most central for the blue group. Finally, node 11 is a bridge node which is crucial for the flow of information between the two groups.
[0106] Suppose further that security for this small system is of interest. Then one can immediately identify nodes 9 , 13 , and 11 as most urgently needing protection from whatever threats the system faces. Nodes 9 and 13 are to be protected because they are centres of their regions: if they are infected, then there is a high probability that their entire region will also be infected.
[0107] Furthermore, one can give node 9 a higher priority for protection than node 13 , since its region is larger. Finally, node 11 merits extra protection, since if it can be rendered immune to the threats, then these threats have no ready channel for spreading from one region to another.
[0108] Note that the use of Rule 2 does not single out any border nodes for special protection—even though node 11 clearly plays an important role in connecting the two regions. However, Rule 2 will identify the link between 11 and 13 as a bridge link. The obvious consequence of this is that the nodes on each end of each bridge link deserve special protective measures.
[0109] This problem can be turned on its head, by giving the administrator the problem of spreading desired information over this same small network. The analysis then suggests an efficient strategy for doing so: one starts with the centres (nodes 9 and 13), and arranges for the desired information to be broadcast from there.
[0110] It is of course to be expected that the distance rule and the steepest-ascent rule will give conflicting results for some nodes. An important point to be gleaned from FIGS. 2 through 7 is that the general qualitative picture is rather insensitive to the choice of rule for defining regions. One can expect this to be the case for most graphs. The choice of centres is independent of which rule is used; and these centres in turn exist precisely because they lie in a region of the graph that has some ‘weight’—that is, some number of nodes which are better connected to one another than to their ‘surroundings’. In short, the distinct rules, which ostensibly define regions, actually differ principally according to where they place the boundaries between regions-while the regions are in themselves rather stable objects.
[0000] Summary of the Definitions of Roles and Regions in Networks.
[0111] The basic criterion for defining a region (and its centre) has been well-connectedness, as measured by the ‘smooth’ graph function, eigenvector centrality or EVC. In addition to defining natural clusters of a graph, our approach also assigns a unique role to each node in the graph.
[0112] The two rules defining regions give qualitatively similar pictures for the graph structure as a whole, but rather different pictures in terms of which roles for nodes are present in the analysis.
[0113] That is, Rule 1 —associating nodes with regions based purely on their distance, in shortest path hops, from centres—places a significant number of nodes in the border set. These nodes in turn can be placed in two distinct roles: bridge nodes, and danglers (see FIG. 2 ). Rule 2 holds more closely to the ‘topographic’ spirit of the approach as described within the present application, associating nodes with centres to which they are linked by a steepest-path ascent. This rule normally (in the absence of special symmetry) places no nodes in the border set-such that, with Rule 2, the two roles in the border set (bridge nodes and danglers) are essentially excluded, and all nodes are either centres of a region, or members of a region.
[0114] One can imagine other rules for defining regions. The principal aspect of the approach according to the present invention is to identify centres first, and then let regions ‘grow’ outwards from these centres. Both of the rules in accordance with the present invention fit this picture. The Girvan/Newman approach allows for a hierarchical decomposition of a graph, by breaking clusters into sub clusters, etc. A similar hierarchical decomposition could also be done according to the present invention, by eliminating border nodes and links, and applying the analysis according to the present invention to the resulting isolated regions. Further roles can be defined based on the present analysis methods. In a very simple example, one can assign the role of “Edge of the region” to those nodes which are connected to border elements (nodes or links). A different type of Edge role may be assigned to those nodes which are ‘farthest’ from the centre, but not linked to any border elements.
[0000] Applications.
[0115] In the following, there are given applications of the method and system according to the present invention. Clearly, both highly central nodes, and bridges (links or nodes) can be singled out as deserving extra attention and care in the preventing of the spread of damage. The highly central nodes are most likely to infect their regions; and the bridges in turn must be guarded so that the infection does not spread from one region to others. Hence it would be practical to immunize certain elements, and so ensure that any infection is isolated to a single region. For larger regions, it would also be practical to immunize the most central nodes in each region—prioritizing of course those regions with the greatest number of nodes. Some instances like very well-connected peer-to-peer systems, on the other hand, are hard to protect, because they are too well-connected. This means that there are many nodes in each region with roughly the same centrality, and that there are many bridges between regions (for those cases where there are more than one region).
[0116] The use of the system and method is applicable to many other types of graphs—in principle to any graph which is undirected. The method is easily modified—as described in the first embodiment—also to allow weights (other than 0 or 1) for the links between nodes. The method and system according to the present invention will prove to be useful in the analysis of social networks—which may (again) have a (positive) strength associated with each link.
[0117] When an innovation—a new product or service—is introduced into a population, the diffusion of the innovation follows a typical pattern. The innovation is usually discovered by a small group of early adopters, and after a while, depending on the early adopters' approval, the opinion leaders (or leading adopters) adopt the innovation. This is the critical point of the diffusion process, because the adoption of the innovation by the majority population usually depends on the acceptance of the opinion leaders [6]. In other words, adoption of an innovation takes off when the opinion leaders or social network hubs approve and adopt the innovation.
[0118] The method as disclosed by the embodiment and its accompanying examples of the present invention, uses a modified adjacency matrix, based on flow-data, to compute a centrality measure for each node in a social network. This centrality index allows the most central nodes of the social network that this adjacency matrix represents to be picked out. These nodes—the network hubs—are, in social network terms, opinion leaders. They are thus good targets for spreading of information etc., because they can potentially contribute to the acceleration of the diffusion of such information. An obvious application of the method is thus in the area of innovation diffusion.
[0119] In the introductory part references have been made to epidemiology, telecommunication, datacom, electric power systems etc. It can be added that the result of the analysis according to the present invention further has a wide range of applications. One example is planning of timetables within transport, or transmission and distribution systems. By analysing traffic flow in a network of roads or a railway system, the best timing for distribution could be found to avoid traffic congestion. Similarly, planning of traffic routing within telecom and datacom, as well as traffic planning on a more general basis, is an obvious application of the present invention, because the method easily can identify congestion points or good routes. Still further on a more microscopic level it can be used within design of computers, for analysing internal traffic and thereby optimising its components and its buses. The latter is particularly useful within the area of parallel processing, to reduce traffic between processors/computers.
[0120] Note that while in the foregoing, there has been provided a detailed description of the present invention, it is to be understood that equivalents are to be included within the scope of the invention as claimed. The detailed description has to a large extent dealt with the theory behind the present invention, however the use of these theories has a broad field of applications, provided the graphs are undirected.
[0121] Thus on a general basis the method according to the present invention is applicable within a wide area of fields and it can be applied for solving problems within these areas. Other advantageous embodiments of the present invention will be evident from the enclosed dependent claims.
ABBREVIATIONS AND REFERENCES
[0122] 1. G. D. BATISTA, P. EADES, R. TAMASSIA, AND I. G. TOLLIS, Graph Drawing: Algorithms for the Visualization of Graphs , Prentice Hall, Upper Saddle River, N.J., 1999.
[0123] 2. P. BONACICH, Factoring and weighting approaches to status scores and clique identification , Journal of Mathematical Sociology, 2 (1972), pp. 113-120.
[0124] 3. M. BURGESS, G. CANRIGHT, AND K. ENGØ, A graph theoretical model of computer security: from file access to social engineering , International Journal of Information Security, (2003). submitted for publication.
[0125] 4. G. CANRIGHT, K. ENGØ-MONSEN, AND Å. WELTZIEN, Multiplex structure of the communications network in a small working group , Social Networks—An International Journal of Structural Analysis, (2003). submitted for publication.
[0126] 5. M. GIRVAN AND M. NEWMAN, Community structure in social and biological networks , Proc. Natl. Acad. Sci. USA, 99 (2002), pp. 8271-8276.
[0127] 6. E. M. ROGERS, Diffusion of Innovations. Free Press, Fifth Edition, 2003.
[0128] 7. J. M. KLEINBERG, Authoritative sources in a hyperlinked environment , Journal of the ACM, 46 (1999), pp. 604-632.
[0129] 8. M. NEWMAN, The structure and function of complex networks , SIAM Review, 45 (2003), pp. 167-256.
[0130] 9. A. Y. NG, A. X. ZHENG, AND M. I. JORDAN, Stable algorithms for link analysis , in Proc. 24th Annual Intl. ACM SIGIR Conference, ACM, 2001.
[0131] 10. A. ORAM, ed., Peer - to - peer: Harnessing the Power of Disruptive Technologies , O'Reilly, Sebastopol, California, 2001.
[0132] 11. L. PAGE, S. BRIN, R. MOTWANI, AND T. WINOGRAD, The pagerank citation ranking: Bringing order to the web , tech. report, Stanford Digital Library Technologies Project, 1998.
[0133] 12. R. PASTOR-SATORRAS AND A. VESPIGNANI, Epidemic spreading in scale - free networks , Phys. Rev. Lett., 86 (2001), pp. 3200-3203.
[0134] 13. T. H. STANG, F. POURBAYAT, M. BURGESS, G. CANRIGHT, K. ENGØ, AND Å. WELTZIEN, Archipelago: A network security analysis tool , in Proceedings of The 17 th Annual Large Installation Systems Administration Conference (LISA 2003), San Diego, Calif., USA, October 2003.
[0135] 14. G. H. GOLUB AND C. H. VAN LOAN, Matrix Computations . The Johns Hopkins University Press, Second Edition, 1989. | A method is disclosed for determining the ability of a network to spread information or physical traffic. Said network includes a number of network nodes interconnected by links. The method comprises mapping the topology of a network, computing a value for link strength between the nodes, computing an Eigenvector Centrality index for all nodes, based on said link strength values identifying nodes which are local maxima of the Eigenvector Centrality index as centre nodes, grouping the nodes into regions surrounding each identified centre node, assigning a role to each node from its position in a region, as centre nodes, region member nodes, border nodes, bridge nodes, dangler nodes, and measuring the susceptibility of the network to spreading, based on the number of regions, their size, and how they are connected. | 7 |
RELATED ART
This application claims priority to U.S. Provisional Patent No. 60/520,886, which was filed on Nov. 18, 2003.
TECHNICAL FIELD OF INVENTION
The present invention relates to eyewear, and in particular, to a design for an auxiliary eyewear display mount. More specifically, the present invention discloses a display mount that allows auxiliary eyewear to be displayed along with the primary eyewear it is designed to combine with. The primary lens assembly can be supported in a conventional manner in an existing display rack. The auxiliary eyewear display mount is attachable to the bridge portion of the primary lens assembly with a hand-operated clamp. An arm extends from the clamp to an auxiliary cradle that supports the auxiliary lens assembly.
BACKGROUND OF THE INVENTION
The eyewear market provides numerous options for people who rely on eyewear in their daily lives. The multitude of different requirements that individuals have, has created a large market of auxiliary lens systems of eyewear. In these systems, a primary lens assembly is augmented by an auxiliary lens assembly. The combinations provide numerous options for satisfying individual requirements for visual assistance and protection.
An example of the utility of combining a primary lens assembly with an auxiliary lens assembly is when the primary lenses are corrective lenses and the auxiliary lenses are light transmission reducing lenses, for example, a polarizing, absorbing, refracting, photochromatic, or reflecting lenses, or any combination thereof (i.e., sunglasses). Another example is when the primary lenses are corrective lenses and the auxiliary lenses are impact resistant safety lenses.
The recent surge in popularity of these devices has created a need for a means to display the devices for retail selection and purchase. Presently, there are no devices available for conveniently displaying to the prospective buyer, both the primary and auxiliary lens assemblies, in a manner that allows the prospective buyer to see how the primary and auxiliary lens assemblies together, and that utilizes existing displays.
Presently, numerous display systems permit display and accessibility to a single lens assembly. For example, U.S. Pat. No. D478,227 S to Peyker discloses an ornamental design for a display case for eyewear. U.S. Pat. No. D426,998 to Kidd, discloses another ornamental design for a display case for eyewear. The principal disadvantage of these designs is that they only support a primary lens assembly, and are not capable of displaying an auxiliary lens assembly, or a primary and auxiliary lens assembly combination.
U.S. Pat. No. Des. 371,458 discloses an eyewear support for a display tray. While this support is limited to working in conjunction with tray display system, it also is limited to supporting a singular primary lens assembly.
Auxiliary eyewear systems such as those described above can only support a primary lens assembly to the exclusion of the auxiliary lens assembly. Most of the various prior art designs cannot support an auxiliary lens assembly in a portal for a primary lens assembly, because the auxiliary lens assemblies lack the pivotally attached legs for going over the ears of the wearer that are commonly used to attach the primary lens assembly in the display device. Another disadvantage of the various prior art designs is that they cannot display a primary and auxiliary lens assembly combination.
It can thus be seen that there is a need to develop a design for a device capable of displaying both primary lens assemblies and auxiliary lens assemblies, which allows close comparison of the matching features of the primary lens assemblies and auxiliary lens assemblies, and which can be used in combination with the existing display devices of retail eyewear outlets.
SUMMARY OF THE INVENTION
A primary advantage of the present invention is that it provides a device capable of displaying both primary lens assemblies and auxiliary lens assemblies. Another advantage of the present invention is that it provides a display device for auxiliary lens assemblies that can be used in combination with existing retail outlet display systems that otherwise support only primary lens assemblies. Another advantage of the present invention is that it is easy to use and allows immediate removal of both the auxiliary lens assembly or the primary lens assembly.
Another advantage of the present invention is that it is simple and aesthetically attractive. Other advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed. As referred to hereinabove, the “present invention” refers to one or more embodiments of the present invention which may or may not be claimed, and such references are not intended to limit the language of the claims, or to be used to construe the claims in a limiting manner.
The present invention discloses an eyewear display mount capable of attaching to a primary lens assembly and supporting an auxiliary lens assembly such that the complementary assemblies may be displayed in combination. A primary lens assembly is capable of retaining a pair of primary lenses. An auxiliary lens assembly is capable of retaining a pair of auxiliary lenses. The auxiliary lens assembly may be removably attached to the primary lens assembly. In this manner, the person wearing the eyewear system has two lenses combining to alter the transmission of light to each eye.
In accordance with one aspect of the invention, there is disclosed a unique auxiliary eyewear display mount which is removably attachable to the bridge portion of a primary lens assembly. The display mount comprises a bridge clamp that is removably attachable to the bridge portion of a primary lens assembly. An arm extends outward from the bridge clamp. A cradle is attached to the arm for supporting an auxiliary lens assembly.
In a more preferred embodiment, the bridge clamp has a base attached to the arm. A pivot pin is attached to the base, and a lever is pivotally attached to the base by the pivot pin. A spring member is located on the pivot pin to urge the lever against the base, and thus secure the display mount to the primary lens assembly. In another preferred embodiment, an extension is formed on the base to further secure the display mount to the bridge portion of a primary lens assembly.
In another preferred embodiment, the cradle has an inner flange, an outer flange, and a relief between the inner and outer flanges. In a still more preferred embodiment, the arm is integral to the base.
BRIEF DESCRIPTION OF THE DRAWINGS
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.
The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
FIG. 1 is a front isometric view of a preferred embodiment of the present invention, disclosing an eyewear display mount attached to the bridge portion of a primary lens assembly, with an auxiliary lens assembly supported in the cradle of the display mount.
FIG. 2 is an isometric view of a preferred embodiment of the present invention.
FIG. 3 is a side view of a preferred embodiment of the present invention disclosed in FIG. 2 .
FIG. 4 is a rear isometric view of a preferred embodiment of the present invention, shown attached to a primary lens assembly and supporting an auxiliary lens assembly.
FIG. 5 is a front view of a preferred embodiment of the present invention, shown attached to a primary lens assembly and supporting an auxiliary lens assembly.
FIG. 6 is a side view of a preferred embodiment of the present invention, shown attached to a primary lens assembly and supporting an auxiliary lens assembly.
FIG. 7 is a cross-sectional side view of a preferred embodiment of the present invention, shown attached to a primary lens assembly and supporting an auxiliary lens assembly, with the device and lens assemblies sectioned as indicated in FIG. 5 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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.
The terms “right” and “left” as used herein are referenced from the perspective of a person wearing the primary and auxiliary lens assemblies. The references are intended to aide in the description of the device, and are not intended to be limiting, since the preferred embodiments of the device are generally symmetric.
FIG. 1 is a front isometric view of a preferred embodiment of the present invention. In this view, an eyewear display mount 100 is attached to the bridge portion of a primary lens assembly 200 . An auxiliary lens assembly 300 is supported on display mount 100 .
FIG. 2 is an isometric view of a preferred embodiment of display mount 100 . In the embodiment shown in this view, display mount 100 has a bridge clamp 110 . Bridge clap 110 is attached to an arm 130 . Arm 130 is attached to a cradle 140 .
FIG. 3 is a side view of the same embodiment of display mount 100 shown if FIG. 2 . Referring to FIGS. 2 and 3 , bridge clamp 110 has a base 112 attached to arm 130 . In a preferred embodiment, base 112 has a first sidewall 114 and a substantially parallel second sidewall 116 . In a preferred embodiment, base 112 has an extension 118 extending between sidewall 114 and sidewall 116 , and outward from base 112 .
A pivot pin 120 is attached to base 112 between sidewall 114 and sidewall 116 . A lever 122 is pivotally attached to base 112 by pivot pin 120 . In a preferred embodiment, lever 122 has an upper portion 124 and a lower portion 126 . In a still more preferred embodiment, lever 122 has an offset 128 that provides a radial distance from pivot pin 120 about which upper portion 124 and lower portion 126 pivot. As best seen in FIG. 2 , a spring member 129 is located on pivot pin 120 to urge lever 122 against base 112 .
In a preferred embodiment, cradle 140 has an inner flange 142 and a substantially parallel outer flange 144 . A relief 146 is formed between inner flange 142 and outer flange 144 .
FIGS. 4 , 5 , and 6 , illustrate the bridge clamp 110 of display mount 100 attached to the bridge portion of a primary lens assembly 200 , and an auxiliary lens assembly 300 supported in cradle 140 of display mount 100 .
FIG. 7 is a cross-sectional side view of a preferred embodiment of display mount 100 , shown attached to a primary lens assembly 200 and supporting an auxiliary lens assembly 300 , with display device 100 and lens assemblies 200 and 300 sectioned as indicated in FIG. 5 .
OPERATION OF THE PREFERRED EMBODIMENTS
FIG. 1 is an isometric view of a preferred embodiment of the present invention. In this view, a typical primary lens assembly 200 and a typical auxiliary lens assembly 200 are illustrated as displayed together by use of display mount 100 . Bridge clamp 110 of display mount 100 can be securely clamped onto the middle bridge portion of a primary lens assembly 200 . Arm 130 extends from bridge clamp 110 . The opposite end of arm 130 is attached to cradle 140 . Auxiliary lens assembly 300 can be placed into cradle 140 .
Display mount 100 is attached to primary lens assembly 200 by applying sufficient finger pressure to upper portion 124 of lever 122 to overcome the compressive force of spring member 129 . This provides an opening between lower portion 126 of lever 122 , and base 112 of bridge clamp 110 . Opened bridge clamp 110 is placed over the middle bridge portion of primary lens assembly 200 and released. When released, spring member 129 closes bridge clamp 110 securely on the middle bridge portion of primary lens assembly 200 , as shown in FIGS. 1 , and 4 through 7 .
Auxiliary lens assembly 300 is located on display mount 100 by simply placing it in cradle 140 as also shown in FIGS. 1 , and 4 through 7 . In a preferred embodiment, inner flange 142 and outer flange 144 are spaced sufficiently apart to form a relief 146 . Relief 146 is capable of receiving auxiliary lens assembly 300 between the left and right lenses, or lens frames, and/or the middle bridge portion. The multiple receiving means allows display mount 100 to work with numerous auxiliary lens assemblies 300 of various designs and sizes. In another preferred embodiment, cradle 140 is made of a compressible material, such as a foam rubber. In this embodiment, the compressibility of the material provides additional compressive forces to further secure auxiliary lens assembly 300 in cradle 140 .
In this manner, auxiliary lens assembly 300 can be displayed in visible and comparable combination with primary lens assembly 200 . Primary lens assembly 200 may in turn be mounted in many of the existing eyewear display devices utilized for retail sales. Use of the present invention thus allows a potential purchaser to view the compatibility of primary lens assembly 200 with auxiliary lens assembly 300 , and to contemplate the advantages of the eyewear system. This also permits the potential purchaser to easily and quickly disassemble the display, without the need for instructions, assistance, or tools.
In a preferred embodiment best viewed in FIG. 2 and FIG. 4 , bridge clamp 110 is comprised of base 112 pivotally attached to lever 122 by pivot pin 120 . Spring member 129 urges lever 122 into contact with base 112 , providing the necessary clamping force to secure display mount 100 to primary lens assembly 200 .
In a preferred embodiment best viewed in FIG. 7 , lever 122 includes features to enhance the engagement of bridge clamp 110 with the bridge portion of primary lens assembly 200 . As shown, pivot 120 is attached to an offset 128 . In the preferred embodiment shown in FIG. 7 , offset 128 has a first side and a second side attached outside and adjacent to each of first and second sidewalls 114 and 116 respectively. This positioning allows spring member 129 to coil around pivot pin 120 . Use of offset 128 further improves the release feature of display device 100 by lifting lower portion 126 upwards relative to the bridge member of primary lens assembly 200 when finger pressure is applied to upper portion 124 of lever 122 .
The distance between offset 128 and lower portion 126 provides an allocation of space for the bridge member of primary lens assembly 200 . It further provides opposing and generally perpendicular surfaces to enhance engagement with the bridge member of primary lens assembly 200 . In another preferred embodiment, base 112 includes extension 118 , which provides an opposing and generally perpendicular surface to sidewalls 114 and 116 in a configuration that further secures display mount 100 on primary lens assembly 200 .
In an alternative embodiment not shown, lever 122 contains no offset, and the allocation of space for the bridge member of primary lens assembly 200 is provided by a comparable slot in base 112 . In another embodiment not shown, lever 122 contains no offset, and offset 128 is instead provided on base 112 . In another alternative embodiment, lever 122 and/or base 112 are made of a compressible material that eliminates the need for allocation of space for the bridge member of primary lens assembly 200 .
It 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. One skilled in the art will specifically recognize that alternative arrangements of the disclosed components can achieve an equivalent function and result without departing from the spirit and scope of the present invention. As an example, offset 128 and lower portion 126 can be integrally formed and curved, in a hook style appearance. | The present invention discloses a unique and novel display device for attaching an auxiliary lens assembly to a primary lens assembly. A display mount is disclosed that allows auxiliary eyewear to be displayed along with the primary eyewear to which it combines. The primary lens assembly can be supported in a conventional manner in an existing display rack. The auxiliary eyewear display mount is attachable to the bridge portion of the primary lens assembly with a hand-operated clamp. An arm extends from the clamp to an auxiliary cradle that supports the auxiliary lens assembly. | 8 |
FIELD OF THE INVENTION
This invention relates to insulated concrete wall systems, and more particularly to poured concrete wall systems in which a thermal insulation panel is joined to the concrete wall by an elongate retaining strip having edges engaging grooves formed in opposing vertical edges of the insulating panels.
BACKGROUND OF THE INVENTION
Poured concrete walls are formed by pouring or pumping uncured concrete between rigid planar forms generally made of wood, aluminum, steel or a combination of these materials. Two series of coplanar forms are typically held in spaced-apart, parallel relationship by retaining ties to create a cavity in which the poured concrete wall is formed.
Poured concrete walls can be constructed more quickly and at a lower cost than comparable alternative wall structures, while providing excellent durability, structural integrity, and other aesthetic and functional characteristics. However, poured concrete walls have relatively poor thermal insulating properties, and methods for incorporating insulative material in a poured concrete wall often have been difficult, requiring excessive time, labor and cost. Some of these methods require unconventional wall forms which are more costly to obtain and use than conventional wall forms.
U.S. Patent Application Publication No. U.S. 2001/0000844 A1 (incorporated in its entirety herein) describes an insulated concrete wall structure having embedded wall ties and a series of elongate retaining strips positioned between vertically spaced wall ties. Insulating panels are located between the horizontally spaced wall ties and are retained in position by the retaining strips. An advantage of this system is that an insulated poured concrete wall can be constructed using conventional wall forms in approximately the same amount of time as conventional uninsulated poured concrete walls. The resulting insulated poured wall system can be constructed at a lower cost than other known insulated poured concrete wall systems. Additionally, it is disclosed that the retaining strips allow building material such as drywall or paneling to be attached to the face of the insulating panels once the wall forms are removed and the wall is completed. However, this wall system is deficient in certain respects. First, the elongate retaining strips are not secured directly to the concrete wall, but instead are secured at opposite ends of the retaining strip to wall ties by notches formed in the wall ties. As a result, the elongate retainers are retained along their vertical edges between adjacent insulation panels and at their upper and lower edges between the notches in the vertically spaced-apart ties. This can allow some freedom of movement of the elongate retaining strips when building materials, especially heavy objects such as cabinets, are attached to the elongate retainers. In extreme cases, this can cause structures supported on the elongate retainers to pull away from the wall. Accordingly, there is a need for a more rigid insulation panel retainer that is capable of securely supporting heavier loads.
Another problem with the insulated concrete wall system disclosed by Patent Publication No. U.S. 2001/0000844 A1 is that it requires a plurality of elongate retaining strips between adjacent insulation panels. More specifically, one retaining strip is located between each set of vertically spaced-apart ties. The publication states that the height or length of the retaining strips is dependent upon the distance between adjacent ties, but is typically about one foot in length. Thus, for a typical poured concrete basement wall, eight retaining strips aligned vertically between adjacent insulation panels are needed. To reduce construction costs, it would be desirable to reduce the number of retainers that are required. Because the retainers are vertically spaced-apart, there are areas along the seam between adjacent insulation panels, in the vicinity of the ties, that are unavailable for engagement with a fastener to allow building materials to be attached. As a result, care must be taken to avoid locating fasteners in the area between vertically spaced-apart retaining strips when securing building materials such as drywall or paneling to the insulation panels.
Another disadvantage with the insulated concrete wall system described in United States Patent Application Publication U.S. 2001/0000844 A1 is that the flat surface of the elongate retaining strips can make it difficult to insert fasteners through the retaining strip. In particular, it can be difficult to initiate penetration of a drywall screw through the flat surface of the retaining strips.
SUMMARY OF THE INVENTION
The present invention provides an improved method of forming an insulated poured concrete wall, a system for forming an insulated poured concrete wall, and an insulated poured concrete wall. The invention allows insulated concrete walls to be formed more efficiently and at a lower cost by using fewer components. The invention also allows building materials such as drywall, siding, paneling, and the like, as well as heavier objects, such as cabinets, to be more stably and durably secured to the wall.
In accordance with one aspect of the invention, there is provided a system for forming an insulated poured concrete wall. The system includes spaced-apart wall forms forming opposing wall surfaces that define a cavity, a plurality of insulating panels arranged adjacent at least one of the opposing wall surfaces, and a plurality of elongate retaining strips between adjacent insulating panels, wherein each of the elongate retaining strips includes a portion that projects into the cavity.
In accordance with another aspect of this invention, a method of forming an insulated concrete wall is provided. The method includes arranging a plurality of wall forms in spaced relationship to form opposing wall surfaces defining a cavity, arranging insulating panels adjacent at least one of the opposing wall surfaces, arranging elongate retaining strips between adjacent insulating panels, wherein the elongate retaining strips engage edges of the insulating panels, and wherein a portion of each retaining strip projects into the cavity.
In accordance with another aspect of the invention, there is provided an insulated poured concrete wall comprising a concrete wall having opposing wall surfaces, a plurality of spaced-apart, elongate retaining strips, the elongate retaining strips having a portion embedded in the concrete wall with the length direction of the retaining strips extending vertically. A plurality of insulating panels is provided, with each panel being held between laterally spaced-apart retaining strips.
In accordance with another aspect of the invention, a system for forming an insulated poured concrete wall includes spaced-apart wall forms forming opposing wall surfaces that define a cavity, a plurality of vertically and horizontally spaced-apart wall ties extending between the opposing wall forms, a plurality of insulating panels arranged adjacent at least one of the opposing wall surfaces, and a plurality of elongate retaining strips between adjacent insulating panels, with each elongated retaining strip having at least one notch through which a wall tie passes.
In accordance with another aspect of the invention, there is provided a method of forming an insulated poured concrete wall using a plurality of elongate retaining strips, wherein each elongate retraining strip includes at least one notch that allows a wall tie to pass through.
Another aspect of the invention provides an insulated poured concrete wall comprising a concrete wall having opposing wall surfaces, a plurality of vertically and horizontally spaced wall ties contained within the concrete wall and extending between the opposing wall surfaces, a plurality of insulating panels arranged adjacent at least one of the opposing wall surfaces, and a plurality of elongate retaining strips between adjacent insulating panels, each elongate retaining strip having at least one notch through which a wall tie passes.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an insulated concrete wall system in accordance with the invention.
FIG. 2 is an elevational view of the wall system shown in FIG. 1 .
FIG. 3 is a front view of a retaining strip used in the wall system of this invention.
FIG. 4 is a side view of the retaining strip shown in FIG. 3 .
FIG. 5 is a cross-sectional of the retaining strip shown in FIGS. 3 and 4.
FIG. 6 is a horizontal cross-sectional view of a poured concrete wall in accordance with this invention.
FIG. 7 is a transverse cross-sectional view of an alternative-retaining strip in accordance with this invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In FIG. 1, there is shown a perspective view of a portion of a poured wall forming system 10 embodying the present invention. The system includes a plurality of wall forms 12 which are arranged to form two series of coplanar wall forms held in opposing spaced-apart, parallel relationship. Adjacent wall forms 12 are held in a coplanar relationship by connecting pins 14 , and the two series of coplanar wall forms are held in opposing spaced-apart parallel relationship by wall ties 16 . Wall forms 12 may be constructed of wood, aluminum, iron, steel, or various other materials or combinations thereof.
The forms 12 are typically from about 2 to 6 feet wide and from about 2 to about 10 feet high. Connecting pins 14 are well known in the art. Insulating panels 18 are positioned adjacent the interior surfaces of at least ones of the series of wall forms 12 . Grooves 20 are formed in opposing vertical edges of insulating panel 18 . A long edge 28 of a T-shaped retaining strip 22 is received in groove 20 . Insulating panels 18 are held in place at their edges between laterally spaced-apart retaining strips 22 . As shown in FIG. 2, rather than extending between vertically spaced-apart ties 16 , retainer 22 may extend the full height of the poured wall, e.g., such as 8 or 9 feet. This is achieved by providing a series of vertically spaced-apart notches 24 through which ties 16 pass. Thus, rather than extending between ties 16 , retaining strip 22 extends uninterrupted past wall ties 16 . Retaining strips 22 are temporarily held in place by engagement of notches 24 with notches in the edges of wall ties 16 until the concrete has been poured and cured. This reduces the number of retaining strips 22 which are needed, thus simplifying installation and reducing construction costs. While it is preferred that a single retaining strip 22 extend from floor to ceiling, i.e., the full height of a poured concrete wall, the benefits of the invention can be achieved using a plurality (e.g., two or three) of retaining strips 22 which together extend the full height of the poured concrete wall. In other words, notches 24 which allow ties 16 to pass through the retaining strip 22 facilitate a reduction in the number of retaining strips needed and thereby simplify and reduce the costs associated with installation of the insulated poured wall system.
In addition to reducing the number of retaining strips needed, the retaining strips 22 provide a continuous strip or stud that allows building materials such as drywall or paneling to be attached with fasteners such as screws or nails at any elevation, including an elevation at which a wall tie 16 is present.
A preferred embodiment of a retaining strip 22 in accordance with the invention is shown in further detail in FIGS. 3-5. As shown in FIG. 5, retaining strip 22 has a T-shaped cross-sectional profile, including a web portion 30 , an enlarged (e.g., flared or bulbous) anchor portion 32 at one end of web 30 , and a flange portion 34 at the other end of web 30 . Flange portion 34 is at a right angle with respect to web portion 30 and includes a left (with respect to the drawing shown in FIG. 5) side 36 and a right side 38 . The left side (or half) of flange 34 constitutes a continuous, uninterrupted, rectangular strip, whereas the right side (or half) of flange portion 34 includes spaced-apart notches 24 for accommodating wall ties 16 , i.e. for allowing wall tie 16 to pass through or around the retaining strip 22 .
As shown in FIG. 6, which is a vertical cross section of a finished wall after concrete 40 has been poured between wall forms 12 but before the forms 12 have been removed, anchor portion 32 of retaining strip 22 is embedded within the concrete wall 40 . The T-shaped profile provides improved rigidity and strength for hanging wall coverings such as drywall, paneling, siding (when the insulation is on the exterior side of the wall), etc. Improved rigidity and strength is also achieved by embedding a portion 32 of the retaining strip 22 in concrete wall 40 . The resulting structure shown in FIG. 6, in addition to accommodating wall coverings, can support relatively heavy loads such as large wooden cabinets and the like without warping, buckling, distorting or pulling away from the wall on account of the additional rigidity and strength provided by web 30 and by embedding the anchor portion 32 of retaining strip 22 in concrete wall 40 .
In order to facilitate easier insertion of fasteners into flange portion 34 of retaining strip 22 , flange portion 34 is provided with a serrated surface as shown in FIG. 5 . The serrations help guide a fastener into the flange portion 34 making it easier to initiate penetration of a threaded fastener through flange portion 34 .
The wall structure shown in FIG. 6 is constructed by first assembling the wall forms 12 with the connecting pins 14 and wall tie 16 as shown in FIG. 1 . Thereafter, a plurality of insulating panels 18 and retaining strips 22 are positioned inside the wall forms 12 and along one of the two parallel wall surfaces. The retaining strips 22 are temporarily held in place by the grooves 20 in insulation panels 18 .
Insulating panels 18 can be made of generally any relatively rigid insulating material, such as rigid polyurethane foam or rigid polystyrene foam. Panels 18 can be of generally any width, typically from about 2 feet to about 6 feet, and generally any height, typically from about 2 feet to about 10 feet, and can have any desired thickness, typically from about 2 to about 3 inches.
The retaining strips 22 can be made of any of various suitable materials such as wood, plastic or metal. The web portion 30 and flange portion 34 of retaining strips 22 are relatively thin, typically about ⅛ inch in thickness. The width of the web portion 30 and the flange portion 34 is typically from about 1-½ inches to about 4 inches. Preferably, the retaining strips 22 are made of a material to which conventional fasteners such as screws and nails can be secured.
To create the insulated poured concrete wall, uncured concrete is poured into the cavity formed between the two series of coplanar wall forms 12 . The expression “poured” includes any method or manner in which uncured concrete can be deposited into the cavity between wall forms 12 , whether by hand, from the concrete truck chute, from a pumping system, etc. Once the concrete has set (typically from about 12 to about 24 hours), the forms 12 are removed by releasing the connecting pins 14 from the holes of the walls ties 16 . The forms are then pulled away from the concrete wall. Once the pins and forms are removed, the concrete wall remains with the wall ties 16 embedded within the concrete wall, with insulating panels 18 secured to at least one side of the concrete wall. A portion of wall ties 16 that extends outwardly from the wall surface is typically broken or snapped off.
Although the wall structure shown in the drawings includes insulation panel 16 on only one side of concrete wall 40 , the method of this invention can be employed to provide insulation on both sides of concrete wall 40 . An insulating surface may be provided on only the exterior side of the poured concrete wall such as to facilitate use of flange 34 of retainer 22 to attach exterior siding to the wall. Insulating panels can be provided only on the interior side of the wall with flange portion 34 of retaining strip 22 used for attaching interior drywall, paneling, or the like. When the wall system and method of this invention is used for insulating both sides of a poured concrete wall, the retaining strips on the exterior side of the wall can be used for securing exterior siding to the wall, and the retaining strips on the interior side of the wall can be used for securing drywall or the like.
In FIG. 7, there is shown an alternative embodiment of the retaining strip 122 . Retaining strip 122 includes a segmented web portion including a web portion segment 130 A extending between an exterior flange 134 and a parallel interior flange 135 , and a second web portion segment 130 B extending from interior flange 152 to an enlarged anchor portion 132 . Depending on the dimensions of retaining strip 122 , and the dimensions of insulating panel 18 , insulating panel 18 may be retained between flanges 134 and 152 , or flanges 134 and 152 may engage parallel grooves in the edges of adjacent panels 18 . As another alternative one or the other of flanges 134 and 152 may be engaged in a groove formed in the edge of an insulating panel 18 , while the other flange engages one or the other side of panel 18 . The parallel flange arrangement of retaining strip 122 allows a fastener such as a screw or nail to penetrate two parallel structures (flanges 134 and 152 ), whereby improved strength, rigidity and stability are provided for supporting objects, especially heavy objects such as cabinets and the like.
Web 30 may be scalloped (e.g., have a width that varies along the length of web 30 ) to provide a control joint that limits cracking of concrete wall 40 in a limited area.
The above description is considered that of the preferred embodiments only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the doctrine of equivalents. | An improved method of forming an insulated poured concrete wall, a system for forming an insulated poured concrete wall, and an insulated poured concrete wall are provided. The system includes spaced-apart wall forms defining a cavity, a plurality of insulating panels adjacent at least one of the opposing wall surfaces, and a plurality of the elongate retaining strips between adjacent insulating panels, wherein each of the elongate retaining strips includes a portion that projects into the cavity and/or each of the elongate retaining strips has at least one notch through which a wall tie passes. The system allows building materials such as drywall, siding, paneling, and the like, as well as heavier objects, such as cabinets to be more stably and durably secured to an insulated poured concrete wall, and facilitates construction of an insulated concrete wall using fewer components and less labor. | 4 |
RELATED APPLICATIONS
The present application is related to and claims the priority benefit of each of the following United States Patent Applications: U.S. application Ser. No. 10/837,525, filed Apr. 29, 2004 (now U.S. Pat. No. 7,279,451), which in turn is a continuation in part of each of U.S. Application Ser. No. 10/694,273 (now U.S. Pat. No. 7,534,366) and Ser. No. 10/694,272 (now U.S. Pat. No. 7,230,146), each of which was filed Oct. 27, 2003, and each of which in turn is related to and claims the priority benefit of U.S. Provisional Applications 60/421,263 and 60/421,435, each of which was filed on Oct. 25, 2002. The disclosure of each of the patent applications and patents identified in the preceding sentence is incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to compositions having utility in numerous applications, including particularly refrigeration systems, and to methods and systems utilizing such compositions. In preferred aspects, the present invention is directed to refrigerant compositions comprising at least one multi-fluorinated olefin of the present invention.
BACKGROUND OF THE INVENTION
Fluorocarbon based fluids have found widespread use in many commercial and industrial applications. For example, fluorocarbon based fluids are frequently used as a working fluid in systems such as air conditioning, heat pump and refrigeration applications. The vapor compression cycle is one of the most commonly used type methods to accomplish cooling or heating in a refrigeration system. The vapor compression cycle usually involves the phase change of the refrigerant from the liquid to the vapor phase through heat absorption at a relatively low pressure and then from the vapor to the liquid phase through heat removal at a relatively low pressure and temperature, compressing the vapor to a relatively elevated pressure, condensing the vapor to the liquid phase through heat removal at this relatively elevated pressure and temperature, and then reducing the pressure to start the cycle over again.
While the primary purpose of refrigeration is to remove heat from an object or other fluid at a relatively low temperature, the primary purpose of a heat pump is to add heat at a higher temperature relative to the environment.
Certain fluorocarbons have been a preferred component in many heat exchange fluids, such as refrigerants, for many years in many applications. For, example, fluoroalkanes, such as chlorofluoromethane and chlorofluoroethane derivatives, have gained widespread use as refrigerants in applications including air conditioning and heat pump applications owing to their unique combination of chemical and physical properties. Many of the refrigerants commonly utilized in vapor compression systems are either single components fluids or azeotropic mixtures.
Concern has increased in recent years about potential damage to the earth's atmosphere and climate, and certain chlorine-based compounds have been identified as particularly problematic in this regard. The use of chlorine-containing compositions (such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and the like) as refrigerants in air-conditioning and refrigeration systems has become disfavored because of the ozone-depleting properties associated with many of such compounds. There has thus been an increasing need for new fluorocarbon and hydrofluorocarbon compounds and compositions that offer alternatives for refrigeration and heat pump applications. For example, it has become desirable to retrofit chlorine-containing refrigeration systems by replacing chlorine-containing refrigerants with non-chlorine-containing refrigerant compounds that will not deplete the ozone layer, such as hydrofluorocarbons (HFCs).
It is generally considered important, however, that any potential substitute refrigerant must also possess those properties present in many of the most widely used fluids, such as excellent heat transfer properties, chemical stability, low- or no-toxicity, non-flammability and lubricant compatibility, among others.
Applicants have come to appreciate that lubricant compatibility is of particular importance in many of applications. More particularly, it is highly desirably for refrigeration fluids to be compatible with the lubricant utilized in the compressor unit, used in most refrigeration systems. Unfortunately, many non-chlorine-containing refrigeration fluids, including HFCs, are relatively insoluble and/or immiscible in the types of lubricants used traditionally with CFC's and HFCs, including, for example, mineral oils, alkylbenzenes or poly(alpha-olefins). In order for a refrigeration fluid-lubricant combination to work at a desirable level of efficiently within a compression refrigeration, air-conditioning and/or heat pump system, the lubricant should be sufficiently soluble in the refrigeration liquid over a wide range of operating temperatures. Such solubility lowers the viscosity of the lubricant and allows it to flow more easily throughout the system. In the absence of such solubility, lubricants tend to become lodged in the coils of the evaporator of the refrigeration, air-conditioning or heat pump system, as well as other parts of the system, and thus reduce the system efficiency.
With regard to efficiency in use, it is important to note that a loss in refrigerant thermodynamic performance or energy efficiency may have secondary environmental impacts through increased fossil fuel usage arising from an increased demand for electrical energy.
Furthermore, it is generally considered desirably for CFC refrigerant substitutes to be effective without major engineering changes to conventional vapor compression technology currently used with CFC refrigerants.
Flammability is another important property for many applications. That is, it is considered either important or essential in many applications, including particularly in heat transfer applications, to use compositions, which are non-flammable. Thus, it is frequently beneficial to use in such compositions compounds, which are nonflammable. As used herein, the term “nonflammable” refers to compounds or compositions, which are determined to be nonflammable as determined in accordance with ASTM standard E-681, dated 2002, which is incorporated herein by reference. Unfortunately, many HFCs, which might otherwise be desirable for used in refrigerant compositions are not nonflammable. For example, the fluoroalkane difluoroethane (HFC-152a) and the fluoroalkene 1,1,1-trifluoropropene (HFO-1243zf) are each flammable and therefore not viable for use in many applications.
Higher fluoroalkenes, that is fluorine-substituted alkenes having at least five carbon atoms, have been suggested for use as refrigerants. U.S. Pat. No. 4,788,352—Smutny is directed to production of fluorinated C 5 to C 8 compounds having at least some degree of unsaturation. The Smutny patent identifies such higher olefins as being known to have utility as refrigerants, pesticides, dielectric fluids, heat transfer fluids, solvents, and intermediates in various chemical reactions. (See column 1, lines 11-22).
While the fluorinated olefins described in Smutny may have some level of effectiveness in heat transfer applications, it is believed that such compounds may also have certain disadvantages. For example, some of these compounds may tend to attack substrates, particularly general-purpose plastics such as acrylic resins and ABS resins. Furthermore, the higher olefinic compounds described in Smutny may also be undesirable in certain applications because of the potential level of toxicity of such compounds which may arise as a result of pesticide activity noted in Smutny. Also, such compounds may have a boiling point, which is too high to make them useful as a refrigerant in certain applications.
Bromofluoromethane and bromochlorofluoromethane derivatives, particularly bromotrifluoromethane (Halon 1301) and bromochlorodifluoromethane (Halon 1211) have gained widespread use as fire extinguishing agents in enclosed areas such as airplane cabins and computer rooms. However, the use of various halons is being phased out due to their high ozone depletion. Moreover, as halons are frequently used in areas where humans are present, suitable replacements must also be safe to humans at concentrations necessary to suppress or extinguish fire.
Applicants have thus come to appreciate a need for compositions, and particularly heat transfer compositions, fire extinguishing/suppression compositions, blowing agents, solvent compositions, and compatabilizing agents, that are potentially useful in numerous applications, including vapor compression heating and cooling systems and methods, while avoiding one or more of the disadvantages noted above.
SUMMARY
Applicants have found that the above-noted need, and other needs, can be satisfied by compositions comprising one or more C3 or C4 fluoroalkenes, preferably compounds having Formula I as follows:
XCF z R 3-z (I)
where X is a C 2 or a C 3 unsaturated, substituted or unsubstituted, alkyl radical, each R is independently Cl, F, Br, I or H, and z is 1 to 3. Highly preferred among the compounds of Formula I are the cis- and trans-isomers of 1,3,3,3-tetrafluoropropene (HFO-1234ze)
The present invention provides also methods and systems which utilize the compositions of the present invention, including methods and systems for heat transfer, foam blowing, solvating, flavor and fragrance extraction and/or delivery, and aerosol generation.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The Compositions
The present invention is directed to compositions comprising at least one fluoroalkene containing from 3 to 4 carbon atoms, preferably three carbon atoms, and at least one carbon-carbon double bond. The fluoroalkene compounds of the present invention are sometimes referred to herein for the purpose of convenience as hydrofluoro-olefins or “HFOs” if they contain at least one hydrogen. Although it is contemplated that the HFOs of the present invention may contain two carbon-carbon double bonds, such compounds at the present time are not considered to be preferred.
As mentioned above, the present compositions comprise one or more compounds in accordance with Formula I. In preferred embodiments, the compositions include compounds of Formula II below:
where each R is independently Cl, F, Br, I or H
R′ is (CR 2 ) n Y,
Y is CRF 2
and n is 0 or 1.
In highly preferred embodiments, Y is CF 3 , n is 0 and at least one of the remaining Rs is F.
Applicants believe that, in general, the compounds of the above identified Formulas I and II are generally effective and exhibit utility in refrigerant compositions, blowing agent compositions, compatibilizers, aerosols, propellants, fragrances, flavor formulations, and solvent compositions of the present invention. However, applicants have surprisingly and unexpectedly found that certain of the compounds having a structure in accordance with the formulas described above exhibit a highly desirable low level of toxicity compared to other of such compounds. As can be readily appreciated, this discovery is of potentially enormous advantage and benefit for the formulation of not only refrigerant compositions, but also any and all compositions, which would otherwise contain relatively toxic compounds satisfying the formulas described above. More particularly, applicants believe that a relatively low toxicity level is associated with compounds of Formula II, preferably wherein Y is CF 3 , wherein at least one R on the unsaturated terminal carbon is H, and at least one of the remaining Rs is F. Applicants believe also that all structural, geometric and stereoisomers of such compounds are effective and of beneficially low toxicity.
It is even more preferred that the compounds of the present invention are the tetrafluoropropene and pentafluorpropene compounds in which the unsaturated terminal carbon has not more than one F substituent, specifically: 1,3,3,3-tetrafluoropropene (HFO-1234ze); 2,3,3,3-tetrafluoropropene (HFO-1234yf); and 1,2,3,3,3-pentafluorpropene (HFO-1225ye), and any and all stereoisomers of each of these. Applicant has discovered that such compounds have a very low acute toxicity level, as measured by inhalation exposure to mice and rats.
In highly preferred embodiments, especially embodiments comprising the low toxicity compounds described above, n is zero. In certain highly preferred embodiments the compositions of the present invention comprise one or more tetrafluoropropenes. The term “HFO-1234” is used herein to refer to all tetrafluoropropenes. Among the tetrafluoropropenes, both cis- and trans-1,3,3,3-tetrafluoropropene (HFO-1234ze) are particularly preferred. The term HFO-1234ze is used herein generically to refer to 1,3,3,3-tetrafluoropropene, independent of whether it is the cis- or trans-form. The terms “cisHFO-1234ze” and “transHFO-1234ze” are used herein to describe the cis- and trans-forms of 1,3,3,3-tetrafluoropropene respectively. The term “HFO-1234ze” therefore includes within its scope cisHFO-1234ze, transHFO-1234ze, and all combinations and mixtures of these.
Although the properties of cisHFO-1234ze and transHFO-1234ze differ in at least some respects, it is contemplated that each of these compounds is adaptable for use, either alone or together with other compounds including its stereoisomer, in connection with each of the applications, methods and systems described herein. For example, while transHFO-1234ze may be preferred for use in certain refrigeration systems because of its relatively low boiling point (−19° C.), it is nevertheless contemplated that cisHFO-1234ze, with a boiling point of +9° C., also has utility in certain refrigeration systems of the present invention. Accordingly, it is to be understood that the terms “HFO-1234ze” and 1,3,3,3-tetrafluoropropene refer to both stereo isomers, and the use of this term is intended to indicate that each of the cis- and trans-forms applies and/or is useful for the stated purpose unless otherwise indicated.
HFO-1234 compounds are known materials and are listed in Chemical Abstracts databases. The production of fluoropropenes such as CF 3 CH═CH 2 by catalytic vapor phase fluorination of various saturated and unsaturated halogen-containing C 3 compounds is described in U.S. Pat. Nos. 2,889,379; 4,798,818 and 4,465,786, each of which is incorporated herein by reference. EP 974,571, also incorporated herein by reference, discloses the preparation of 1,1,1,3-tetrafluoropropene by contacting 1,1,1,3,3-pentafluoropropane (HFC-245fa) in the vapor phase with a chromium-based catalyst at elevated temperature, or in the liquid phase with an alcoholic solution of KOH, NaOH, Ca(OH) 2 or Mg(OH) 2 . In addition, methods for producing compounds in accordance with the present invention are described generally in connection with pending United States Patent Application entitled “Process for Producing Fluoropropenes”U.S. Application No. 13/226,019, now Pat. No. 8,247,624), which is also incorporated herein by reference.
The present compositions, particularly those comprising HFO-1234ze, are believed to possess properties that are advantageous for a number of important reasons. For example, applicants believe, based at least in part on mathematical modeling, that the fluoroolefins of the present invention will not have a substantial negative affect on atmospheric chemistry, being negligible contributors to ozone depletion in comparison to some other halogenated species. The preferred compositions of the present invention thus have the advantage of not contributing substantially to ozone depletion. The preferred compositions also do not contribute substantially to global warming compared to many of the hydrofluoroalkanes presently in use.
In certain preferred forms, compositions of the present invention have a Global Warming Potential (GWP) of not greater than about 1000, more preferably not greater than about 500, and even more preferably not greater than about 150. In certain embodiments, the GWP of the present compositions is not greater than about 100 and even more preferably not greater than about 75. As used herein, “GWP” is measured relative to that of carbon dioxide and over a 100-year time horizon, as defined in “The Scientific Assessment of Ozone Depletion, 2002, a report of the World Meteorological Association's Global Ozone Research and Monitoring Project,” which is incorporated herein by reference.
In certain preferred forms, the present compositions also preferably have an Ozone Depletion Potential (ODP) of not greater than 0.05, more preferably not greater than 0.02 and even more preferably about zero. As used herein, “ODP” is as defined in “The Scientific Assessment of Ozone Depletion, 2002, A report of the World Meteorological Association's Global Ozone Research and Monitoring Project,” which is incorporated herein by reference.
The amount of the Formula I compounds, particularly HFO-1234, contained in the present compositions can vary widely, depending the particular application, and compositions containing more than trace amounts and less than 100% of the compound are within broad the scope of the present invention. Moreover, the compositions of the present invention can be azeotropic, azeotrope-like or non-azeotropic. In preferred embodiments, the present compositions comprise HFO-1234, preferably HFO-1234ze, in amounts from about 5% by weight to about 99% by weight, and even more preferably from about 5% to about 95%. Many additional compounds may be included in the present compositions, and the presence of all such compounds is within the broad scope of the invention. In certain preferred embodiments, the present compositions include, in addition to HFO-1234ze, one or more of the following:
Difluoromethane (HFC-32)
Pentafluoroethane (HFC-125)
1,1,2,2-tetrafluoroethane (HFC-134)
1,1,1,2-Tetrafluoroethane (HFC-134a)
Difluoroethane (HFC-152a)
1,1,1,2,3,3,3-Heptafluoropropane (HFC-227ea)
1,1,1,3,3,3-hexafluoropropane (HFC-236fa)
1,1,1,3,3-pentafluoropropane (HFC-245fa)
1,1,1,3,3-pentafluorobutane (HFC-365mfc)
water
CO 2
The relative amount of any of the above noted components, as well as any additional components which may be included in present compositions, can vary widely within the general broad scope of the present invention according to the particular application for the composition, and all such relative amounts are considered to be within the scope hereof.
Heat Transfer Compositions
Although it is contemplated that the compositions of the present invention may include the compounds of the present invention in widely ranging amounts, it is generally preferred that refrigerant compositions of the present invention comprise compound(s) in accordance with Formula I, more preferably in accordance with Formula II, and even more preferably HFO-1234ze, in an amount that is at least about 50% by weight, and even more preferably at least about 70% by weight, of the composition. In many embodiments, it is preferred that the heat transfer compositions of the present invention comprise transHFO-1234ze. In certain preferred embodiments, the heat transfer compositions of the present invention comprise a combination of cisHFO-1234ze and transHFO1234ze in a cis:trans weight ratio of from about 1:99 to about 10:99, more preferably from about 1:99 to about 5:95, and even more preferably from about 1:99 to about 3:97.
The compositions of the present invention may include other components for the purpose of enhancing or providing certain functionality to the composition, or in some cases to reduce the cost of the composition. For example, refrigerant compositions according to the present invention, especially those used in vapor compression systems, include a lubricant, generally in amounts of from about 30 to about 50 percent by weight of the composition. Furthermore, the present compositions may also include a compatibilizer, such as propane, for the purpose of aiding compatibility and/or solubility of the lubricant. Such compatibilizers, including propane, butanes and pentanes, are preferably present in amounts of from about 0.5 to about 5 percent by weight of the composition. Combinations of surfactants and solubilizing agents may also be added to the present compositions to aid oil solubility, as disclosed by U.S. Pat. No. 6,516,837, the disclosure of which is incorporated by reference. Commonly used refrigeration lubricants such as Polyol Esters (POEs) and Poly Alkylene Glycols (PAGs), silicone oil, mineral oil, alkyl benzenes (ABs) and poly(alpha-olefin) (PAO) that are used in refrigeration machinery with hydrofluorocarbon (HFC) refrigerants may be used with the refrigerant compositions of the present invention.
Many existing refrigeration systems are currently adapted for use in connection with existing refrigerants, and the compositions of the present invention are believed to be adaptable for use in many of such systems, either with or without system modification. In many applications the compositions of the present invention may provide an advantage as a replacement in systems, which are currently based on refrigerants having a relatively high capacity. Furthermore, in embodiments where it is desired to use a lower capacity refrigerant composition of the present invention, for reasons of cost for example, to replace a refrigerant of higher capacity, such embodiments of the present compositions provide a potential advantage. Thus, It is preferred in certain embodiments to use compositions of the present invention, particularly compositions comprising a substantial proportion of, and in some embodiments consisting essentially of transHFO-1234ze, as a replacement for existing refrigerants, such as HFC-134a. In certain applications, the refrigerants of the present invention potentially permit the beneficial use of larger displacement compressors, thereby resulting in better energy efficiency than other refrigerants, such as HFC-134a. Therefore the refrigerant compositions of the present invention, particularly compositions comprising transHFP-1234ze, provide the possibility of achieving a competitive advantage on an energy basis for refrigerant replacement applications.
It is contemplated that the compositions of the present, including particularly those comprising HFO-1234ze, also have advantage (either in original systems or when used as a replacement for refrigerants such as R-12 and R-500), in chillers typically used in connection with commercial air conditioning systems. In certain of such embodiments it is preferred to including in the present HFO-1234ze compositions from about 0.5 to about 5% of a flammability suppressant, such as CF3I.
The present methods, systems and compositions are thus adaptable for use in connection with automotive air conditioning systems and devices, commercial refrigeration systems and devices, chillers, residential refrigerator and freezers, general air conditioning systems, heat pumps, and the like.
Blowing Agents, Foams and Foamable Compostions
Blowing agents may also comprise or constitute one or more of the present compositions. As mentioned above, the compositions of the present invention may include the compounds of the present invention in widely ranging amounts. It is generally preferred, however, that for preferred compositions for use as blowing agents in accordance with the present invention, compound(s) in accordance with Formula I, and even more preferably Formula II, are present in an amount that is at least about 5% by weight, and even more preferably at least about 15% by weight, of the composition. In certain preferred embodiments, the blowing agent compositions of the present invention and include, in addition to HFO-1234 (preferably HFO-1234ze) one or more of the following components as a co-blowing agent, filler, vapor pressure modifier, or for any other purpose:
Difluoromethane (HFC-32)
Pentafluoroethane (HFC-125)
1,1,2,2-tetrafluoroethane (HFC-134)
1,1,1,2-Tetrafluoroethane (HFC-134a)
Difluoroethane (HFC-152a)
1,1,1,2,3,3,3-Heptafluoropropane (HFC-227ea)
1,1,1,3,3,3-hexafluoropropane (HFC-236fa)
1,1,1,3,3-pentafluoropropane (HFC-245fa)
1,1,1,3,3-pentafluorobutane (HFC-365mfc)
water
CO 2
it is contemplated that the blowing agent compositions of the present invention may comprise cisHFO-1234ze, transHFO1234ze or combinations thereof. In certain preferred embodiments, the blowing agent composition of the present invention comprise his a combination of cisHFO-1234ze and transHFO1234ze in a cis:trans weight ratio of from about 1:99 to about 10:99, and even more preferably from about 1:99 to about 5:95.
In other embodiments, the invention provides foamable compositions, and preferably polyurethane, polyisocyanurate and extruded thermoplastic foam compositions, prepared using the compositions of the present invention. In such foam embodiments, one or more of the present compositions are included as or part of a blowing agent in a foamable composition, which composition preferably includes one or more additional components capable of reacting and/or foaming under the proper conditions to form a foam or cellular structure, as is well known in the art. The invention also relates to foam, and preferably closed cell foam, prepared from a polymer foam formulation containing a blowing agent comprising the compositions of the invention. In yet other embodiments, the invention provides foamable compositions comprising thermoplastic or polyolefin foams, such as polystyrene (PS), polyethylene (PE), polypropylene (PP) and polyethyleneterpthalate (PET) foams, preferably low-density foams.
In certain preferred embodiments, dispersing agents, cell stabilizers, surfactants and other additives may also be incorporated into the blowing agent compositions of the present invention. Surfactants are optionally but preferably added to serve as cell stabilizers. Some representative materials are sold under the names of DC-193, B-8404, and L-5340 which are, generally, polysiloxane polyoxyalkylene block co-polymers such as those disclosed in U.S. Pat. Nos. 2,834,748, 2,917,480, and 2,846,458, each of which is incorporated herein by reference. Other optional additives for the blowing agent mixture may include flame retardants such as tri(2-chloroethyl)phosphate, tri(2-chloropropyl)phosphate, tri(2,3-dibromopropyl)-phosphate, tri(1,3-dichloropropyl) phosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, aluminum trihydrate, polyvinyl chloride, and the like.
Propellant and Aerosol Compositions
In another aspect, the present invention provides propellant compositions comprising or consisting essentially of a composition of the present invention, such propellant composition preferably being a sprayable composition. The propellant compositions of the present invention preferably comprise a material to be sprayed and a propellant comprising, consisting essentially of, or consisting of a composition in accordance with the present invention. Inert ingredients, solvents, and other materials may also be present in the sprayable mixture. Preferably, the sprayable composition is an aerosol. Suitable materials to be sprayed include, without limitation, cosmetic materials such as deodorants, perfumes, hair sprays, cleansers, and polishing agents as well as medicinal materials such as anti-asthma components, anti-halitosis components and any other medication or the like, including preferably any other medicament or agent intended to be inhaled. The medicament or other therapeutic agent is preferably present in the composition in a therapeutic amount, with a substantial portion of the balance of the composition comprising a compound of Formula I of the present invention, preferably HFO-1234, and even more preferably HFO-1234ze.
Aerosol products for industrial, consumer or medical use typically contain one or more propellants along with one or more active ingredients, inert ingredients or solvents. The propellant provides the force that expels the product in aerosolized form. While some aerosol products are propelled with compressed gases like carbon dioxide, nitrogen, nitrous oxide and even air, most commercial aerosols use liquefied gas propellants. The most commonly used liquefied gas propellants are hydrocarbons such as butane, isobutane, and propane. Dimethyl ether and HFC-152a (1,1-difluoroethane) are also used, either alone or in blends with the hydrocarbon propellants. Unfortunately, all of these liquefied gas propellants are highly flammable and their incorporation into aerosol formulations will often result in flammable aerosol products.
Applicants have come to appreciate the continuing need for nonflammable, liquefied gas propellants with which to formulate aerosol products. The present invention provides compositions of the present invention, particularly and preferably compositions comprising HFO-1234, and even more preferably HFO-1234ze, for use in certain industrial aerosol products, including for example spray cleaners, lubricants, and the like, and in medicinal aerosols, including for example to deliver medications to the lungs or mucosal membranes. Examples of this includes metered dose inhalers (MDIs) for the treatment of asthma and other chronic obstructive pulmonary diseases and for delivery of medicaments to accessible mucous membranes or intranasally. The present invention thus includes methods for treating ailments, diseases and similar health related problems of an organism (such as a human or animal) comprising applying a composition of the present invention containing a medicament or other therapeutic component to the organism in need of treatment. In certain preferred embodiments, the step of applying the present composition comprises providing a MDI containing the composition of the present invention (for example, introducing the composition into the MDI) and then discharging the present composition from the MDI.
The compositions of the present invention, particularly compositions comprising or consisting essentially of HFO-1234ze, are capable of providing nonflammable, liquefied gas propellant and aerosols that do not contribute substantially to global warming. The present compositions can be used to formulate a variety of industrial aerosols or other sprayable compositions such as contact cleaners, dusters, lubricant sprays, and the like, and consumer aerosols such as personal care products, household products and automotive products. HFO-1234ze is particularly preferred for use as an important component of propellant compositions for in medicinal aerosols such as metered dose inhalers. The medicinal aerosol and/or propellant and/or sprayable compositions of the present invention in many applications include, in addition to compound of formula (I) or (II) (preferably HFO-1234ze), a medicament such as a beta-agonist, a corticosteroid or other medicament, and, optionally, other ingredients, such as surfactants, solvents, other propellants, flavorants and other excipients. The compositions of the present invention, unlike many compositions previously used in these applications, have good environmental properties and are not considered to be potential contributors to global warming. The present compositions therefore provide in certain preferred embodiments substantially nonflammable, liquefied gas propellants having very low Global Warming potentials.
Flavorants and Fragrances
The compositions of the present invention also provide advantage when used as part of, and in particular as a carrier for, flavor formulations and fragrance formulations. The suitability of the present compositions for this purpose is demonstrated by a test procedure in which 0.39 grams of Jasmone were put into a heavy walled glass tube. 1.73 grams of R-1234ze were added to the glass tube. The tube was then frozen and sealed. Upon thawing the tube, it was found that the mixture had one liquid phase. The solution contained 20 wt. % Jasome and 80 wt. % R-1234ze, thus establishing its favorable use as a carrier or part of delivery system for flavor formulations, in aerosol and other formulations. It also establishes its potential as an extractant of fragrances, including from plant matter.
Methods and Systems
The compositions of the present invention are useful in connection with numerous methods and systems, including as heat transfer fluids in methods and systems for transferring heat, such as refrigerants used in refrigeration, air conditioning and heat pump systems. The present compositions are also advantageous for in use in systems and methods of generating aerosols, preferably comprising or consisting of the aerosol propellant in such systems and methods. Methods of forming foams and methods of extinguishing and suppressing fire are also included in certain aspects of the present invention. The present invention also provides in certain aspects methods of removing residue from articles in which the present compositions are used as solvent compositions in such methods and systems.
Heat Transfer Methods
The preferred heat transfer methods generally comprise providing a composition of the present invention and causing heat to be transferred to or from the composition changing the phase of the composition. For example, the present methods provide cooling by absorbing heat from a fluid or article, preferably by evaporating the present refrigerant composition in the vicinity of the body or fluid to be cooled to produce vapor comprising the present composition. Preferably the methods include the further step of compressing the refrigerant vapor, usually with a compressor or similar equipment to produce vapor of the present composition at a relatively elevated pressure. Generally, the step of compressing the vapor results in the addition of heat to the vapor, thus causing an increase in the temperature of the relatively high-pressure vapor. Preferably, the present methods include removing from this relatively high temperature, high pressure vapor at least a portion of the heat added by the evaporation and compression steps. The heat removal step preferably includes condensing the high temperature, high-pressure vapor while the vapor is in a relatively high-pressure condition to produce a relatively high-pressure liquid comprising a composition of the present invention. This relatively high-pressure liquid preferably then undergoes a nominally isoenthalpic reduction in pressure to produce a relatively low temperature, low-pressure liquid. In such embodiments, it is this reduced temperature refrigerant liquid which is then vaporized by heat transferred from the body or fluid to be cooled.
In another process embodiment of the invention, the compositions of the invention may be used in a method for producing heating which comprises condensing a refrigerant comprising the compositions in the vicinity of a liquid or body to be heated. Such methods, as mentioned hereinbefore, frequently are reverse cycles to the refrigeration cycle described above.
Foam Blowing Methods
One embodiment of the present invention relates to methods of forming foams, and preferably polyurethane and polyisocyanurate foams. The methods generally comprise providing a blowing agent composition of the present inventions, adding (directly or indirectly) the blowing agent composition to a foamable composition, and reacting the foamable composition under the conditions effective to form a foam or cellular structure, as is well known in the art. Any of the methods well known in the art, such as those described in “Polyurethanes Chemistry and Technology,” Volumes I and II, Saunders and Frisch, 1962, John Wiley and Sons, New York, N.Y., which is incorporated herein by reference, may be used or adapted for use in accordance with the foam embodiments of the present invention. In general, such preferred methods comprise preparing polyurethane or polyisocyanurate foams by combining an isocyanate, a polyol or mixture of polyols, a blowing agent or mixture of blowing agents comprising one or more of the present compositions, and other materials such as catalysts, surfactants, and optionally, flame retardants, colorants, or other additives.
It is convenient in many applications to provide the components for polyurethane or polyisocyanurate foams in pre-blended formulations. Most typically, the foam formulation is pre-blended into two components. The isocyanate and optionally certain surfactants and blowing agents comprise the first component, commonly referred to as the “A” component. The polyol or polyol mixture, surfactant, catalysts, blowing agents, flame retardant, and other isocyanate reactive components comprise the second component, commonly referred to as the “B” component. Accordingly, polyurethane or polyisocyanurate foams are readily prepared by bringing together the A and B side components either by hand mix for small preparations and, preferably, machine mix techniques to form blocks, slabs, laminates, pour-in-place panels and other items, spray applied foams, froths, and the like. Optionally, other ingredients such as fire retardants, colorants, auxiliary blowing agents, and even other polyols can be added as a third stream to the mix head or reaction site. Most preferably, however, they are all incorporated into one B-component as described above.
It is also possible to produce thermoplastic foams using the compositions of the invention. For example, conventional polystyrene and polyethylene formulations may be combined with the compositions in a conventional manner to produce rigid foams.
Cleaning Methods
The present invention also provides methods of removing containments from a product, part, component, substrate, or any other article or portion thereof by applying to the article a composition of the present invention. For the purposes of convenience, the term “article” is used herein to refer to all such products, parts, components, substrates, and the like and is further intended to refer to any surface or portion thereof. Furthermore, the term “contaminant” is intended to refer to any unwanted material or substance present on the article, even if such substance is placed on the article intentionally. For example, in the manufacture of semiconductor devices it is common to deposit a photoresist material onto a substrate to form a mask for the etching operation and to subsequently remove the photoresist material from the substrate. The term “contaminant” as used herein is intended to cover and encompass such a photo resist material.
Preferred methods of the present invention comprise applying the present composition to the article. Although it is contemplated that numerous and varied cleaning techniques can employ the compositions of the present invention to good advantage, it is considered to be particularly advantageous to use the present compositions in connection with supercritical cleaning techniques. Supercritical cleaning is disclosed in U.S. Pat. No. 6,589,355, which is assigned to the assignee of the present invention and incorporated herein by reference. For supercritical cleaning applications, is preferred in certain embodiments to include in the present cleaning compositions, in addition to the HFO-1234 (preferably HFO-1234ze), one or more additional components, such as CO 2 and other additional components known for use in connection with supercritical cleaning applications. It may also be possible and desirable in certain embodiments to use the present cleaning compositions in connection with particular vapor degreasing and solvent cleaning methods.
Flammability Reduction Methods
According to certain other preferred embodiments, the present invention provides methods for reducing the flammability of fluids, said methods comprising adding a compound or composition of the present invention to said fluid. The flammability associated with any of a wide range of otherwise flammable fluids may be reduced according to the present invention. For example, the flammability associated with fluids such as ethylene oxide, flammable hydrofluorocarbons and hydrocarbons, including: HFC-152a, 1,1,1-trifluoroethane (HFC-143a), difluoromethane (HFC-32), propane, hexane, octane, and the like can be reduced according to the present invention. For the purposes of the present invention, a flammable fluid may be any fluid exhibiting flammability ranges in air as measured via any standard conventional test method, such as ASTM E-681, and the like.
Any suitable amounts of the present compounds or compositions may be added to reduce flammability of a fluid according to the present invention. As will be recognized by those of skill in the art, the amount added will depend, at least in part, on the degree to which the subject fluid is flammable and the degree to which it is desired to reduce the flammability thereof. In certain preferred embodiments, the amount of compound or composition added to the flammable fluid is effective to render the resulting fluid substantially non-flammable.
Flame Suppression Methods
The present invention further provides methods of suppressing a flame, said methods comprising contacting a flame with a fluid comprising a compound or composition of the present invention. Any suitable methods for contacting the flame with the present composition may be used. For example, a composition of the present invention may be sprayed, poured, and the like onto the flame, or at least a portion of the flame may be immersed in the composition. In light of the teachings herein, those of skill in the art will be readily able to adapt a variety of conventional apparatus and methods of flame suppression for use in the present invention.
Sterilization Methods
Many articles, devices and materials, particularly for use in the medical field, must be sterilized prior to use for the health and safety reasons, such as the health and safety of patients and hospital staff. The present invention provides methods of sterilizing comprising contacting the articles, devices or material to be sterilized with a compound or composition of the present invention comprising a compound of Formula I, preferably HFO-1234, and even more preferably HFO-1234ze, in combination with one or more sterilizing agents. While many sterilizing agents are known in the art and are considered to be adaptable for use in connection with the present invention, in certain preferred embodiments sterilizing agent comprises ethylene oxide, formaldehyde, hydrogen peroxide, chlorine dioxide, ozone and combinations of these. In certain embodiments, ethylene oxide is the preferred sterilizing agent. Those skilled in the art, in view of the teachings contained herein, will be able to readily determine the relative proportions of sterilizing agent and the present compound(s) to be used in connection with the present sterilizing compositions and methods, and all such ranges are within the broad scope hereof. As is known to those skilled in the art, certain sterilizing agents, such as ethylene oxide, are relatively flammable components, and the compound(s) in accordance with the present invention are included in the present compositions in amounts effective, together with other components present in the composition, to reduce the flammability of the sterilizing composition to acceptable levels.
The sterilization methods of the present invention may be either high or low-temperature sterilization of the present invention involves the use of a compound or composition of the present invention at a temperature of from about 250° F. to about 270° F., preferably in a substantially sealed chamber. The process can be completed usually in less than about 2 hours. However, some articles, such as plastic articles and electrical components, cannot withstand such high temperatures and require low-temperature sterilization. In low temperature sterilization methods, the article to be sterilized is exposed to a fluid comprising a composition of the present invention at a temperature of from about room temperature to about 200° F., more preferably at a temperature of from about room temperature to about 100° F.
The low-temperature sterilization of the present invention is preferably at least a two-step process performed in a substantially sealed, preferably air tight, chamber. In the first step (the sterilization step), the articles having been cleaned and wrapped in gas permeable bags are placed in the chamber. Air is then evacuated from the chamber by pulling a vacuum and perhaps by displacing the air with steam. In certain embodiments, it is preferable to inject steam into the chamber to achieve a relative humidity that ranges preferably from about 30% to about 70%. Such humidities may maximize the sterilizing effectiveness of the sterilant, which is introduced into the chamber after the desired relative humidity is achieved. After a period of time sufficient for the sterilant to permeate the wrapping and reach the interstices of the article, the sterilant and steam are evacuated from the chamber.
In the preferred second step of the process (the aeration step), the articles are aerated to remove sterilant residues. Removing such residues is particularly important in the case of toxic sterilants, although it is optional in those cases in which the substantially non-toxic compounds of the present invention are used. Typical aeration processes include air washes, continuous aeration, and a combination of the two. An air wash is a batch process and usually comprises evacuating the chamber for a relatively short period, for example, 12 minutes, and then introducing air at atmospheric pressure or higher into the chamber. This cycle is repeated any number of times until the desired removal of sterilant is achieved. Continuous aeration typically involves introducing air through an inlet at one side of the chamber and then drawing it out through an outlet on the other side of the chamber by applying a slight vacuum to the outlet. Frequently, the two approaches are combined. For example, a common approach involves performing air washes and then an aeration cycle.
EXAMPLES
The following examples are provided for the purpose of illustrating the present invention but without limiting the scope thereof.
Example 1
The coefficient of performance (COP) is a universally accepted measure of refrigerant performance, especially useful in representing the relative thermodynamic efficiency of a refrigerant in a specific heating or cooling cycle involving evaporation or condensation of the refrigerant. In refrigeration engineering, this term expresses the ratio of useful refrigeration to the energy applied by the compressor in compressing the vapor. The capacity of a refrigerant represents the amount of cooling or heating it provides and provides some measure of the capability of a compressor to pump quantities of heat for a given volumetric flow rate of refrigerant. In other words, given a specific compressor, a refrigerant with a higher capacity will deliver more cooling or heating power. One means for estimating COP of a refrigerant at specific operating conditions is from the thermodynamic properties of the refrigerant using standard refrigeration cycle analysis techniques (see for example, R. C. Downing, FLUOROCARBON REFRIGERANTS HANDBOOK, Chapter 3, Prentice-Hall, 1988).
A refrigeration/air conditioning cycle system is provided where the condenser temperature is about 150° F. and the evaporator temperature is about −35° F. under nominally isentropic compression with a compressor inlet temperature of about 50° F. COP is determined for several compositions of the present invention over a range of condenser and evaporator temperatures and reported in Table I below, based upon HFC-134a having a COP value of 1.00, a capacity value of 1.00 and a discharge temperature of 175° F.
TABLE I
DISCHARGE
REFRIGERANT
Relative
TEMPERATURE
COMPOSITION
Relative COP
CAPACITY
° F.
HFO 1225ye
1.02
0.76
158
HFO trans-1234ze
1.04
0.70
165
HFO cis-1234ze
1.13
0.36
155
HFO 1234yf
0.98
1.10
168
This example shows that certain of the preferred compounds for use with the present compositions each have a better energy efficiency than HFC-134a (1.02, 1.04 and 1.13 compared to 1.00) and the compressor using the present refrigerant compositions will produce discharge temperatures (158, 165 and 155 compared to 175), which is advantageous since such result will likely leading to reduced maintenance problems.
Example 2
The miscibility of HFO-1225ye and HFO-1234ze with various refrigeration lubricants is tested. The lubricants tested are mineral oil (C3), alkyl benzene (Zerol 150), ester oil (Mobil EAL 22 cc and Solest 120), polyalkylene glycol (PAG) oil (Goodwrench Refrigeration Oil for 134a systems), and a poly(alpha-olefin) oil (CP-6005-100). For each refrigerant/oil combination, three compositions are tested, namely 5, 20 and 50 weight percent of lubricant, with the balance of each being the compound of the present invention being tested
The lubricant compositions are placed in heavy-walled glass tubes. The tubes are evacuated, the refrigerant compound in accordance with the present invention is added, and the tubes are then sealed. The tubes are then put into an air bath environmental chamber, the temperature of which is varied from about −50° C. to 70° C. At roughly 10° C. intervals, visual observations of the tube contents are made for the existence of one or more liquid phases. In a case where more than one liquid phase is observed, the mixture is reported to be immiscible. In a case where there is only one liquid phase observed, the mixture is reported to be miscible. In those cases where two liquid phases were observed, but with one of the liquid phases occupying only a very small volume, the mixture is reported to be partially miscible.
The polyalkylene glycol and ester oil lubricants were judged to be miscible in all tested proportions over the entire temperature range, except that for the HFO-1225ye mixtures with polyalkylene glycol, the refrigerant mixture was found to be immiscible over the temperature range of −50° C. to −30° C. and to be partially miscible over from −20 to 50° C. At 50 weight percent concentration of the PAG in refrigerant and at 60°, the refrigerant/PAG mixture was miscible. At 70° C., it was miscible from 5 weight percent lubricant in refrigerant to 50 weight percent lubricant in refrigerant.
Example 3
The compatibility of the refrigerant compounds and compositions of the present invention with PAG lubricating oils while in contact with metals used in refrigeration and air conditioning systems is tested at 350° C., representing conditions much more severe than are found in many refrigeration and air conditioning applications.
Aluminum, copper and steel coupons are added to heavy walled glass tubes. Two grams of oil are added to the tubes. The tubes are then evacuated and one gram of refrigerant is added. The tubes are put into an oven at 350° F. for one week and visual observations are made. At the end of the exposure period, the tubes are removed.
This procedure was done for the following combinations of oil and the compound of the present invention:
a) HFO-1234ze and GM Goodwrench PAG oil b) HFO1243 zf and GM Goodwrench oil PAG oil c) HFO-1234ze and MOPAR-56 PAG oil d) HFO-1243 zf and MOPAR-56 PAG oil e) HFO-1225 ye and MOPAR-56 PAG oil.
In all cases, there is minimal change in the appearance of the contents of the tube. This indicates that the refrigerant compounds and compositions of the present invention are stable in contact with aluminum, steel and copper found in refrigeration and air conditioning systems, and the types of lubricating oils that are likely to be included in such compositions or used with such compositions in these types of systems.
Comparative Example
Aluminum, copper and steel coupons are added to a heavy walled glass tube with mineral oil and CFC-12 and heated for one week at 350° C., as in Example 3. At the end of the exposure period, the tube is removed and visual observations are made. The liquid contents are observed to turn black, indicating there is severe decomposition of the contents of the tube.
CFC-12 and mineral oil have heretofore been the combination of choice in many refrigerant systems and methods. Thus, the refrigerant compounds and compositions of the present invention possess significantly better stability with many commonly used lubricating oils than the widely used prior art refrigerant-lubricating oil combination.
Example 4
Polyol Foam
This example illustrates the use of blowing agent in accordance with one of the preferred embodiments of the present invention, namely the use of HFO-1234ze, and the production of polyol foams in accordance with the present invention. The components of a polyol foam formulation are prepared in accordance with the following table:
PBW Polyol Component* Voranol 490 50 Voranol 391 50 Water 0.5 B-8462 (surfactant) 2.0 Polycat 8 0.3 Polycat 41 3.0 HFO-1234ze 35 Total 140.8 Isocyanate M-20S 123.8 Index 1.10 *Voranol 490 is a sucrose-based polyol and Voranol 391 is a toluene diamine based polyol, and each are from Dow Chemical. B-8462 is a surfactant available from Degussa-Goldschmidt. Polycat catalysts are tertiary amine based and are available from Air Products. Isocyanate M-20S is a product of Bayer LLC.
The foam is prepared by first mixing the ingredients thereof, but without the addition of blowing agent. Two Fisher-Porter tubes are each filled with about 52.6 grams of the polyol mixture (without blowing agent) and sealed and placed in a refrigerator to cool and form a slight vacuum. Using gas burets, about 17.4 grams of HFO-1234ze are added to each tube, and the tubes are then placed in an ultrasound bath in warm water and allowed to sit for 30 minutes. The solution produced is hazy, a vapor pressure measurement at room temperature indicates a vapor pressure of about 70 psig, indicating that the blowing agent is not in solution. The tubes are then placed in a freezer at 27° F. for 2 hours. The vapor pressure was again measured and found to be 14-psig. The isocyanate mixture, about 87.9 grams, is placed into a metal container and placed in a refrigerator and allowed to cool to about 50° F. The polyol tubes were then opened and weighed into a metal mixing container (about 100 grams of polyol blend are used). The isocyanate from the cooled metal container is then immediately poured into the polyol and mixed with an air mixer with double propellers at 3000 RPM's for 10 seconds. The blend immediately begins to froth with the agitation and is then poured into an 8×8×4 inch box and allowed to foam. Because of the froth, a cream time cannot be measured. The foam has a 4-minute gel time and a 5-minute tack free time. The foam is then allowed to cure for two days at room temperature.
The foam is then cut to samples suitable for measuring physical properties and is found to have a density of 2.14 pcf. K-factors are measured and found to be as follows:
Temperature
K, BTU In/Ft 2 h ° F.
40° F.
.1464
75° F.
.1640
110°
.1808
Example 5
Polystyrene Foam
This example illustrates the use of blowing agent in accordance with two preferred embodiments of the present invention, namely the use of HFO-1234ze and HFO-1234-yf, and the production of polystyrene foam. A testing apparatus and protocol has been established as an aid to determining whether a specific blowing agent and polymer are capable of producing a foam and the quality of the foam. Ground polymer (Dow Polystyrene 685D) and blowing agent consisting essentially of HFO-1234ze are combined in a vessel. A sketch of the vessel is illustrated below. The vessel volume is 200 cm 3 and it is made from two pipe flanges and a section of 2-inch diameter schedule 40 stainless steel pipe 4 inches long (see Figure 1). The vessel is placed in an oven, with temperature set at from about 190° F. to about 285° F., preferably for polystyrene at 265° F., and remains there until temperature equilibrium is reached.
The pressure in the vessel is then released, quickly producing a foamed polymer. The blowing agent plasticizes the polymer as it dissolves into it. The resulting density of the two foams thus produced using this method are given in Table 1 and graphed in Figure 1 as the density of the foams produced using trans-HFO-1234ze and HFO-1234yf. The data show that foam polystyrene is obtainable in accordance with the present invention. The die temperature for R1234ze with polystyrene is about 250° F.
TABLE 1
Dow polystyrene 685D
Foam density (lb/ft 3 )
T ° F.
transHFO-1234ze
HFO-1234yf
275
55.15
260
22.14
14.27
250
7.28
24.17
240
16.93 | Disclosed are the use of fluorine substituted olefins, including tetra- and penta-fluoropropenes, in a variety of applications, including in methods of depositing catalyst on a solid support, methods of sterilizing articles, cleaning methods and compositions, methods of applying medicaments, fire extinguishing/suppression compositions and methods, flavor formulations, fragrance formulations and inflating agents. | 8 |
FIELD OF THE INVENTION
This application is a Divisional of U.S. application Ser. No. 09/262,064 filed on Mar. 4, 1999, now U.S. Pat. No. 6,665,361 hereby incorporated by reference as to its entirety. The present invention relates to a communication method and apparatus, and in particular a method and apparatus for mobile satellite communication which provides a short processing delay, a high coding gain and efficient use of bandwidth.
BACKGROUND OF THE INVENTION
Voice, fax and data communication capabilities are available through mobile satellite communication systems. For example, the Inmarsat-M™ and Inmarsat mini-M™ systems support a data rate of 2.4 kbit/s, while the Inmarsat-B™ system provides data rates of up to 16 kbit/s. However, in terrestrial communications data rates of 28.8 kbit/s are commonly used over a PSTN under the ITU V.34 standard, and data rates of 56 or 64 kbit/s per channel are available over ISDN. Many internet-based and conferencing applications require the data rates available over terrestrial networks. Such applications cannot be used satisfactorily on conventional mobile satellite terminals.
Mobile satellite communication channels are subject to many different sources of noise as well as fading, particularly when the mobile terminal is moving. However, bit error rates of 10 −6 or less are desirable if the service is to have performance comparable with terrestrial data communications, which limits the data rate operable on the satellite channel. The data can be encoded for error correction so as to reduce the bit error rate, but this also reduces the data rate.
Satellite communications typically involve much greater delay than terrestrial communications. As well as the propagation delay between an earth station and a satellite, delay is also incurred in formatting data into transmission frames and in encoding the data to provide error detection and correction. Complex coding and decoding algorithms can reduce the bit error rate of a satellite channel, but these algorithms generally involve buffering and intensive processing, which add to the delay. Excessive delay is inimical to real-time applications such as telephony and conferencing.
U.S. Pat. No. 5,568,483 describes a method for formatting data of different data rates for transmission over a transmission medium. European patent publication No. 0 676 875 A discloses a transmission method for wireless circuits such as satellite circuits, in which data is encoded at a variable rate depending on the priority of the data transmitted.
International patent publication No. WO 96/164492 discloses a wireless digital transmission technique in which pilot symbols are inserted periodically in a stream of data symbols.
According to one aspect of the present invention, there is provided a satellite communications technique in which a pilot symbol is transmitted after every 25 or 29 data symbols.
According to another aspect of the present invention, there is provided a method of transmitting both user data and in-band signaling information such that frames are transmitted containing either multiplexed user data and signalling information or multiplexed signaling information and dummy data, with the frame length being the same in either case.
According to another aspect of the present invention, there is provided a method of formatting user data, which is received in user data frames comprising four subframes each of equal length, into output frames each corresponding to an integral number of user data frames.
SUMMARY OF THE INVENTION
According to another aspect of the present invention, there is provided a satellite communications system in which data can be transmitted by any one of a plurality of different data rates, selected such that each of said data rates can be achieved by dividing a clock rate by only small prime numbers a small number of times.
It is one advantage of aspects of the present invention that low signalling overhead and wastage of bandwidth may be achieved. It is another advantage that a frame length is chosen to incur a low framing delay while having a sufficiently large frame to achieve a high error correction coding gain.
BRIEF DESCRIPTION OF THE DRAWINGS
Specific embodiments of the present invention will now be described with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a satellite communications system;
FIG. 2 a is a schematic diagram of a transmitter in the system of FIG. 1 ;
FIG. 2 b is a schematic diagram of a receiver in the system of FIG. 1 ;
FIG. 3 is a schematic diagram of a turbo encoder in the transmitter of FIG. 2 a;
FIG. 4 is a diagram of the modulation scheme implemented by the modulator in FIG. 2 a;
FIG. 5 is a diagram of the frame format used for communication between the earth stations in a first embodiment of the present invention;
FIGS. 6 a to 6 d are diagrams showing details of the frame format of FIG. 5 in a data transmission mode;
FIGS. 7 a to 7 c are diagrams showing details of the frame format of FIG. 5 in a signalling mode;
FIG. 8 is a diagram of the frame format used for communication between the earth stations in a second embodiment of the present invention;
FIGS. 9 a to 9 d are diagrams showing details of the frame format of FIG. 8 in a data transmission mode;
FIGS. 10 a to 10 c are diagrams showing details of the frame format of FIG. 8 in a signalling mode;
FIG. 11 is a diagram of the frame format used for communication between the earth stations in a third embodiment of the present invention;
FIGS. 12 a to 12 e are diagrams showing details of the frame format of FIG. 11 in a data transmission mode;
FIGS. 13 a to 13 c are diagrams showing details of the frame format of FIG. 11 in a signalling mode;
FIGS. 14 a to 14 c are diagrams showing the format of MIU frames in the first embodiment when applied to facsimile transmission;
FIGS. 15 a to 15 c are diagrams showing the format of MIU frames when applied to facsimile or multimedia transmission in the second embodiment;
FIG. 16 is a protocol level diagram showing the system of FIG. 1 in a multimedia mode; and
FIG. 17 shows a modification of the formats of the first to third embodiments.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1 , mobile terminal equipment 4 is connected to a mobile earth station (MES) 6 . The mobile terminal equipment 4 sends digital data to the MES 6 for RF modulation and transmission to a satellite 8 , and the MES 6 receives and demodulates digital data from the satellite 8 , the demodulated data then being sent to the mobile terminal equipment 4 .
The satellite 8 carries a multibeam antenna 9 which generates a plurality of spot beams SB 1 to SB 5 for transmission and reception of signals over a user link, together with a global beam GB which covers the coverage areas of all the spot beams SB. The satellite 8 also carries a feeder link antenna 11 which generates a feeder link beam FB directed towards a land earth station (LES) 10 , for transmission and reception of signals over a feeder link.
The satellite 8 carries transponders which receive modulated signals in each of the spot beams SB and the global beam GB, convert them to an intermediate frequency, amplify them and retransmit them at a different frequency from the received frequency in the feeder link beam FB. Likewise, signals transmitted by the LES 10 in the feeder link beam FB are retransmitted at a different frequency in one of the spot beams B or the global beam GB. The satellite 8 thereby links the MES 6 to the LES 10 , so that signals transmitted by the MES 6 are received by the LES 10 and vice versa, via the satellite 8 .
During call set-up, signals are transmitted and received by the MES 6 in the global beam GB, and channels are assigned in one of the spot beams SB in which the MES 6 is located. Transmission and reception of user data then takes place in the spot beam channels. Examples of such arrangements are the Inmarsat-3™ satellites which support the Inmarsat mini-M™ service.
The LES 10 is connected through a network 14 , in this case a PSTN, to fixed terminal equipment 18 , which comprises telephone, facsimile or data terminal equipment compatible with the mobile terminal equipment 4 , together with a suitable interface to the network 14 , such as a PSTN modem. The network 14 may alternatively be an ISDN (Integrated Services Digital Network).
FIG. 2 a shows the relevant functional sections of a transmitter section of the MES 6 and the LES 10 . The functions of the MES 6 and the LES 10 are distinct in other respects, but for convenience the same diagram and reference numerals are used for the relevant sections of each. Parallel data connections are shown by double diagonal lines.
An interface portion 20 comprises a port interface 20 a for connection to the network 14 or to the mobile terminal equipment 4 . The port interface 20 a comprises a physical connector appropriate to the connection, such as an RJ11 connector for two-wire analogue connection or an RS-232C connector for digital connection. If the connection is analogue, a demodulator is also included in the port interface 20 a . The interface portion 20 also includes a buffer 20 b to permit flow control and/or plesiochronous buffering. Data is output from the interface portion 20 to a modem interface unit (MIU) 22 which implements communications protocols compatible with those of the mobile terminal equipment 4 and the fixed terminal equipment 18 . For example, the MIU 22 may implement facsimile protocols compatible with ITU Recommendation T.30. If the network 14 is an ISDN, the MIU 22 may translate ISDN signalling messages to satellite signalling messages.
Data is output from the MIU 22 to a multiplexer 24 where the data is multiplexed with signalling information input from a signalling unit buffer 25 The output of the multiplexer 24 is scrambled by a scrambler 26 using a scrambling vector determined during call set-up and encoded by a encoder 28 . The encoder 28 implements a parallel concatenated convolutional code known as a ‘Turbo’ code, which provides a type of forward error correction particularly well suited to digital radio frequency transmission. The encoder is shown in more detail in FIG. 3 . The data and parity bits output by the encoder 28 are buffered by a transmit synchroniser 30 and output as sets of four bits to a 16QAM (16 state quadrature amplitude modulation) modulator 32 , which modulates each set of four bits as one 16QAM symbol. The transmit synchroniser also receives data sets which comprise a unique word (UW) of 40 symbols. The 16QAM symbols are transmitted to the satellite 8 , with the unique word being transmitted at the beginning of a data transmission in order to identify the channel to the receiver.
The timing of the transmitter is controlled by a clock 34 , which provides frame and symbol timing signals to the portions of the transmitter.
FIG. 2 b shows the relevant functional sections of a receiver section of the MES 6 and the LES 10 . The functions of the MES 6 and the LES 10 are distinct in other respects, but for convenience the same diagram and reference numerals are used for the relevant sections of each. The functions of the receiver portion are the inverse of corresponding functions of the transmitter portion shown in FIG. 2 a and the same reference numerals are therefore used, with a dash to denote the inverse, in FIG. 2 b.
Symbols received from the satellite 8 are demodulated by a 16QAM demodulator 32 ′ and output as four bits to a phase/unique word detector 30 ′ which acquires the phase and frame timing of the received signal, as well as detecting the unique word. The received data is decoded by a decoder 28 ′, which decodes the turbo encoded data using a MAP (maximum a priori) or SOVA (soft output Viterbi algorithm) decoder. The decoded data is descrambled by a descrambler 26 ′, using the inverse of a scrambling vector used by the scrambler 26 . The descrambled data is demultiplexed by a demultiplexer 24 ′ which demultiplexes user data from signalling information, the latter being stored in a signalling unit buffer 25 ′. The data is sent through a modem interface unit 22 ′ to an interface portion 20 ′ for connection to the network 14 or mobile terminal equipment 4 . The interface portion 20 ′ comprises a port interface 20 a ′ and a buffer 20 b′.
A clock 35 provides frame and symbol synchronisation signals to the different parts of the receiver.
An example of a Turbo encoder suitable for use in the encoder 28 is shown in FIG. 3 . Data bits d k are input to a first encoder ENC 1 , and to an interleaver 29 , the output of which is connected to a second encoder ENC 2 . Each encoder ENC 1 and ENC 2 is a recursive convolutional coder comprising four intermediate binary stores D 1 to D 4 , and binary adders or exclusive-OR gates. With each cycle, the contents of each of the binary stores D 1 to D 3 is shifted to binary stores D 2 to D 4 respectively, while the new contents of D 1 are derived from the previous contents of D 2 to D 4 . The output p k from the first encoder and the output q k from the second encoder are derived from the contents of the binary stores D 1 , D 2 and D 4 and from the input to the binary store D 1 .
The data bits d k , the non-interleaved parity bits p k and the interleaved parity bits q k are output to the transmit synchroniser 30 from which sets of bits (u 1 , u 2 , u 3 , u 4 ) are output in parallel in accordance with a puncturing format, in which only some of the parity bits are output. In some of the sets of bits, two data bits d k and two parity bits p k or q k are output, giving a half-rate code. In others of the sets three data bits d k and one parity bit p k or q k are output, giving a three-quarter rate code. The proportion of half and three-quarter rate coded sets is arranged to give a predetermined coding rate.
Each set of bits is modulated as one symbol by the 16QAM modulator 32 . Each symbol is formed from the four bits (u 1 , u 2 , u 3 , u 4 ) with the bits u 1 , u 2 modulating the I (amplitude) component and the bits u 3 , u 4 modulating the Q (phase) component such that:
A i =[u 1 , u 2 ]→I
B j =[u 3 , u 4 ]→Q
The modulation scheme, as shown in FIG. 4 , is square 16QAM, although a circular 16QAM scheme may be used. The data bits u 1 , u 3 are the most protected in the 16QAM symbol. The constellation mapping is summarised in Table 1 below, where D is the minimum distance between points.
TABLE 1
I1
I0
Q1
Q0
I
Q
0
1
0
1
−3D/2
−3D/2
0
1
0
0
−3D/2
−D/2
0
1
1
0
−3D/2
D/2
0
1
1
1
−3D/2
3D/2
0
0
0
1
−D/2
−3D/2
0
0
0
0
−D/2
−D/2
0
0
1
0
−D/2
D/2
0
0
1
1
−D/2
3D/2
1
0
0
1
D/2
−3D/2
1
0
0
0
D/2
−D/2
1
0
1
0
D/2
D/2
1
0
1
1
D/2
3D/2
1
1
0
1
3D/2
−3D/2
1
1
0
0
3D/2
−D/2
1
1
1
0
3D/2
D/2
1
1
1
1
3D/2
3D/2
In a first embodiment of the present invention, a user data rate of 14.4 kbit/s is supported in a single channel per carrier (SCPC) frame format as shown in FIG. 5 . Each frame F carries a header containing a unique word (UW), comprising a predetermined sequence of 40 symbols, to assist in acquiring the signal and determining the signal type. The unique word symbols comprise only two bits, mapped onto the most protected bits u 1 , u 3 of 16 QAM constellation.
The duration of each frame is 160 ms. The end of a sequence of frames is indicated by an end of data (EOD) signal. The format of the body of the frame differs depending on whether data or signalling is being transmitted.
FIG. 6 a shows the frame format input to the modulator 32 in a data mode, in which data is transmitted between the mobile terminal equipment 4 and the fixed terminal equipment 18 . The unique word comprises a data unique word UW D which indicates that the body of the frame F contains user data. The body of the frame comprises 47 sequences of 25 data symbols DS each followed by one pilot symbol PS, and a final sequence of the frame, which comprises 17 data symbols followed by one pilot symbol PS. The pilot symbols allow measurement of fading and noise variance, so as to assist in decoding of the turbo codes. Thus, each frame contains 1192 data symbols, 48 pilot symbols and 40 unique word symbols.
As shown in FIG. 6 b , the data symbols in each frame comprise two subframes SF 1 and SF 2 each comprising 596 symbols of encoded data generated by the encoder 28 . As shown in FIG. 6 c , each subframe SF is generated by the encoder 28 from a corresponding multiplexed frame MF 1 , MF 2 output from the multiplexer 24 through the scrambler 26 , comprising 1184 data bits D and 48 signalling unit bits SU. As shown in FIG. 6 d , each set of data bits D in each multiplexed frame MF comprises two MIU frames M 1 , M 2 output by the MIU 22 , each comprising 592 bits. Hence, 2368 data bits are transmitted every 160 ms, giving a user data rate of 14.8 kbit/s.
The size of the interleaver 29 of the encoder 28 is equal to that of each of the multiplexed frames MF 1 and MF 2 . In one example, the interleaver 29 is a random interleaver in which an entire multiplexed frame MF is loaded into the interleaver 29 and the contents are then output in a pseudo-random order to the second encoder ENC 2 to generate the interleaved parity bits q for the encoded subframe SF. The encoders ENC 1 and ENC 2 are reset for each new multiplexed frame MF.
FIG. 7 a shows the format of the frame of FIG. 5 in an in-band signalling mode. The format is similar to that shown in FIG. 6 a , except that the unique word comprises a signalling unique word UW S different from the data unique word UW D , to indicate that the body of the frame contains signalling information only. FIG. 7 b shows that the frame F comprises two sub-frames SF 1 and SF 2 , as in FIG. 6 b . However, the multiplexed frames MF 1 , MF 2 shown in FIG. 7 c differ from those of FIG. 6 c in that the data bits D comprise 1040 dummy bits generated by the multiplexer 24 and not carrying any user data. The multiplexed frame MF carries two signalling unit slots SU 1 and SU 2 each comprising 96 bits of signalling information. Each signalling unit slot SU is used in the in-band signalling mode to transmit signalling messages during call set-up and clearing.
In a second embodiment of the present invention, a user data rate of 28.8 kbit/s is supported. Similar formats to those of the first embodiment are indicated by the same references. The frame structure is shown in FIG. 8 , which is similar to that of FIG. 5 except that the frame duration is 80 ms instead of 160 ms.
FIGS. 9 a to 9 c show formats for a data transmission mode similar to those of FIGS. 6 a to 6 c , except that the durations of the subframes SF and multiplexed frames MF are halved, although the number of bits therein remains the same. However, the format shown in FIG. 9 d differs from that shown in FIG. 6 d , in that the data bits D of each multiplexed frame comprise only one MIU frame M of 1184 bits. Hence, 2368 bits of user data are transmitted every 80 ms, giving a data rate of 29.6 kbit/s, sufficient to support a user data rate of 28.8 kbit/s.
FIGS. 10 a and 10 b show formats for an in-band signalling mode similar to those of FIGS. 7 a and 7 b , except that the durations of the frames F and subframes SF are halved. However, the format of FIG. 10 c differs from that of FIG. 7 c in that each multiplexed frame MF comprises 1136 dummy data bits D and one signalling unit slot SU of 96 bits. This gives the same signalling rate as the first embodiment in in-band signalling mode.
In a third embodiment of the present invention, a user rate of 56 or 64 kbit/s is supported, which is compatible with a single ISDN channel. FIG. 11 shows the frame structure, which is similar to that shown in FIG. 8 .
FIG. 12 a shows the frame format in a data transmission mode. The format differs from that of FIG. 10 a in that 2688 symbols are transmitted in each frame F. The data unique word UW D occupies the first 40 symbols, while the remainder of the frame comprises 88 sets of 29 symbols each followed by a pilot symbol PS, followed by the last set which comprises only 8 symbols and no pilot symbol. As shown in FIG. 12 b , the subframes SF each comprise 5120 bits which are modulated as 1280 symbols. As shown in FIG. 12 c , each multiplexed frame MF comprises 2560 data bits D and 48 signalling unit bits SU. As shown in FIG. 12 d , the data bits D are input as one frame M from the network 14 or mobile terminal equipment 4 .
In this embodiment, 5120 bits are transmitted every 80 ms, giving a user data rate of 64 kbit/s. Where the network 14 or mobile terminal 4 transmits at 56 kbit/s, every eighth data bit D is unused, as shown in FIG. 12 e.
FIG. 13 a shows the frame format in an in-band signalling mode of the third embodiment. The symbol format is the same as that shown in FIG. 12 a , except that the signalling unique word UW S is transmitted instead of the data unique word UW D . As shown in FIG. 13 b , the frame F is divided into two sub-frames SF 1 and SF 2 , in the same way as shown in FIG. 12 b . As shown in FIG. 13 c , each multiplexed frame MF comprises a data slot D of 2512 dummy bits and a signalling unit slot SU of 96 bits.
The features of the formats of the embodiments are summarised in Table 2 below.
TABLE 2
Embodiment
1
2
3
Supported Data Rate (kbit/s)
14.4
28.8
56/64
Modulation Scheme
16QAM
16QAM
16QAM
Data Rate (kbit/s)
14.8
29.6
64
Signalling Rate (kbit/s)
0.6
1.2
1.2
Total bit rate (kbit/s)
15.4
30.8
65.2
MIU frame length (ms)
40
40
40
MIU frame size (bits)
592
1184
5120
Subframe SF length (ms)
80
40
40
Data bits per subframe SF
1184
1184
2560
Signalling bits per subframe
48
48
96
SF
Input bits per subframe SF
1232
1232
2608
Coding rate
0.516778
0.516778
0.509375
Output bits per subframe SF
2384
2384
5120
Output symbols per subframe
596
596
1280
SF
Frame F length (ms)
160
80
80
Data symbols per frame F
1192
1192
2560
Pilot symbol Insertion Ratio
1/26*
1/26*
1/30 †
Pilot symbols per frame F
48
48
88
Unique Word length
40
40
40
(symbols)
Frame size (symbols)
1280
1280
2688
Symbol Rate (ksymbols/s)
8
16
33.6
*1 pilot symbol after every 25 data symbols
† 1 pilot symbol after every 29 data symbols
The transmitter and receiver portions of the MES 6 and of the LES 10 are preferably operable in any one of a plurality of different modes corresponding to ones of the embodiments described above. For example, the transmitter and receiver portions may support rates of both 14.4 kbit/s and 28.8 kbit/s over the satellite link, the rate being selected during call set-up.
The symbol rates of 8, 16 and 33.6 ksymbols/s have been selected so that the transmitter clock 34 and receiver clock 35 can be designed with an internal clock rate which can easily be divided to produce synchronizing clock pulses at 8, 16 and 33.6 kHz. The lowest common multiple of these clock rates is 336 kHz, and if this is set as the internal clock rate, division by 42, 21 and 10 respectively is required. Suitable dividers can easily be implemented in hardware by means of a small number of divisions by prime numbers up to 7.
The input data rates of 14.4, 28.8, 56 and 64 kbit/s have a lowest common multiple of 4032 kbit/s. If the symbol rates were proportional to the input data rates, the internal clock rate of the transmitter clock 34 and of the receiver clock 35 would have to be divided by 280, 140, 72 and 63 respectively.
Thus, by varying the coding rate for different input data rates and by appropriate selection of frame formats, the design requirements of the transmitter and receiver clocks are simplified.
Facsimile Application
Applications of the above embodiments to facsimile communications will now be described with reference to FIGS. 14 a to 14 c and 15 a to 15 c . In this case, the mobile terminal equipment 4 and the fixed terminal equipment 18 comprise a facsimile terminal or a computer implementing facsimile protocols such as ITU Recommendation T.30.
FIG. 14 a shows the MIU frames M as shown in FIG. 6 d , each comprising 592 bits. As shown in FIG. 14 b , each MIU frame is subdivided into four blocks each comprising a control field C 1 to C 4 of 16 bits and a data block B 1 to B 4 of 144 bits.
FIG. 15 a shows the MIU frames M as shown in FIG. 9 d , each comprising 1184 bits. As shown in FIG. 15 b , each MIU frame is subdivided into four blocks each comprising a control field C 1 to C 4 of 32 bits and a data block B 1 to B 4 of 288 bits. As shown in FIG. 15 c , each control field C is subdivided into a 16 bit spare field and a 16 bit control field.
The numbering of the bits used in each data block B for different end-to-end facsimile data rates are given below in Table 3. The other bits are not used.
TABLE 3 Fax Data Rate (kbit/s) Embodiment 1 Embodiment 2 0.3 6k + n; k = 0 to 23; n = 1* 12k + n; k = 0 to 23; n = 1* 2.4 6k + n; k = 0 to 23; n = 1 12k + n; k = 0 to 23; n = 1 4.8 3k + n; k = 0 to 47; n = 1 6k + n; k = 0 to 47; n = 1 7.2 2k + n; k = 0 to 71; n = 1 4k + n; k = 0 to 71; n = 1 9.6 3k + n; k = 0 to 47; n = 1 3k + n; k = 0 to 95; n = 1 to 2 12 6k + n; k = 0 to 23; n = 1 12k + n; k = 0 to 23; n = 1 to to 5 5 14.4 all slots 2k + n; k = 0 to 143; n = 1 16.8 N/A 12k + n; k = 0 to 23; n = 1 to 7 19.2 N/A 3k + n; k = 0 to 95; n = 1 to 2 21.6 N/A 4k + n; k = 0 to 71; n = 1 to 3 24 N/A 6k + n; k = 0 to 47; n = 1 to 5 26.4 N/A 12k + n; k = 0 to 23; n = 1 to 11 28.8 N/A all slots *Each bit is repeated 8 times
Multimedia Application
FIG. 16 is a protocol diagram showing an example of multimedia protocols implemented by the fixed terminal equipment 18 , the network 14 , the LES 10 , the MES 6 and the mobile terminal equipment 4 in the system of FIG. 1 .
In this example, the fixed terminal equipment 18 comprises a personal computer (PC) 18 a running multimedia teleconferencing software and complying with ITU Recommendations H.324, which defines standards for low bit-rate teleconferencing over a PSTN. Framing of the multimedia data is implemented according to ITU Recommendation H.223. The personal computer is connected to a PSTN modem 18 b via an RS232 physical connection and communicates therewith using the ITU V.80 protocol and timing.
The PSTN modem 18 b terminates the V.80 protocol and communicates over the network 14 , which is a PSTN in this case, with the LES 10 by means of a synchronous V.34 protocol, using H.223 framing. The LES 10 communicates with the MES 6 using the 28.8 kbit/s mode described above with reference to the second embodiment.
The MES 6 communicates with the mobile terminal 4 using the V.80 protocol and an RS232 physical connection. The mobile terminal 4 implements the H.223 and H.324 protocols transparently end-to-end with the fixed user terminal 18 . The mobile user terminal 4 is in this case a portable personal computer PC running multimedia teleconferencing software compatible with that running on the fixed user terminal PC.
The channel format used for multimedia communications is the same as that used for facsimile services in the second embodiment, as shown in FIG. 15 , with the same rate adaptation format described above with reference to Table 3 in relation to the second embodiment.
A further feature which may be applied to the frame formats of any of the first, second and third embodiments will now be described with reference to FIG. 17 of the drawings. This arrangement differs from that of FIG. 5 in that a short preamble P is transmitted at the beginning of a burst of frames F, after a period of silence on the SCPC channel. Reference is made to co-pending application number [Agent's Ref: J.40112GB], the contents of which are incorporated by reference in so far as they relate to a data carrier activation technique for a 64 kbit/s satellite channel similar to that of the third embodiment of the present application. The carrier word comprises a repeated sequence of the following 16QAM symbol, in the same modulation scheme as that shown in FIG. 4 :
TABLE 4
Preamble
I 1
0
I o
1
Q 1
0
Q o
0
The number of carrier word symbols transmitted in the carrier word varies for each embodiment, as follows:
TABLE 5
Symbol
Embodiment
Number of Symbols
Rate/kSymbols/s
1
4
8
2
8
16
3
16
33.6
The preamble symbol has a power level corresponding to the average power level of the 16 QAM constellation, and the preamble P constitutes a constant power level signal of approximately 500 μs duration. The transmission of the preamble P assists in automatic level control using a feedback loop in a high power amplifier (HPA) in the 16 QAM modulator 32 , so that the transmit power can be ramped up to the required level in 500 μs or less. If the preamble P were not transmitted at the beginning of each burst, the transmission would begin with a unique word UW which does not have a constant power level, and the automatic level control would not reach a stable level for a period considerably exceeding 500 μs.
The embodiments have been described above in terms of functional blocks. However, functions of more than one of these blocks may be performed by a single unit; conversely, the function of one of these blocks may be performed by several discrete units.
The frame formats described above may be applied to other types of service. The formats themselves may be modified while still achieving the advantageous effects thereof. These and other modifications may nevertheless fall within the scope of the present invention as defined by the attached claims. | A set of formats and protocols is proposed for a satellite communications system. In these formats, a pilot signal (PS) is inserted after every 25 or 29 data symbols. The formats consist of SCPC frames (F) which may contain either data (D) and in-band signaling information (SU), or only signaling information (SU). In either case, the contents of each frame (F) are error-correction coded before transmission with the same coding rate. Each data frame (F) carries the data content of an integral number of input user data frames (M), each of which comprises four subframes. Different symbol transmission rates are used for different input data rates, the symbol transmission rates being selected so that their different synchronizing clock rates can easily be obtained from a common clock. Data bursts may be preceded by a constant power level preamble (P). The formats and protocols satisfy the requirements of a high data rate satellite communications system. | 7 |
STATEMENT OF PRIORITY
[0001] This patent application claims priority to U.S. Provisional Patent Application No. 60/183,206, filed on Feb. 17, 2000.
TECHNICAL FIELD OF THE INVENTION
[0002] The invention relates to directional boring machines, and more particularly to a directional boring attachment for boring through the earth in order to lay utility lines, such as gas lines, electrical conduit, communications conduit, sewer lines, and water lines.
BACKGROUND OF THE INVENTION
[0003] Utility lines for water, electricity, gas, telephone and cable television are often run underground for reasons of safety and aesthetics. In many situations, the underground utility pipes, cables, and lines (collectively, “utility lines”) can be buried in an open trench. After the utility lines are buried, the trench is then back-filled to bring it up to grade. Although useful in areas of new construction, the burial of utility lines in an open trench in already developed areas has certain disadvantages. In previously, partially, or fully developed areas, the digging and existence of a trench can cause serious disturbance to structures or roadways. Further, digging a trench in previously developed areas creates a high risk of damaging previously buried utility lines. Another problem with digging an open trench is that structures or roadways disturbed by such digging are rarely restored to their original condition. Furthermore, a trench poses a danger of injury caused by workers or other persons inadvertently falling into the trench, or the collapse of the trench upon people working in the trench.
[0004] The general technique of boring a horizontal underground tunnel in which utility lines are placed has recently been developed in order to overcome the disadvantages described above, as well as others associated with conventional trenching techniques. Conventional directional boring machines typically include an elongated boom having a drill head that moves longitudinally forward and rearward over the length of the boom. The boom is angled relative to the surface (usually the ground) to be drilled at an angle ranging from 5° to 25°. The drill head includes a rotating spindle, generally driven by a hydraulic motor, to which one or more elongated drill stems (also referred to as “casings”) are detachably connected.
[0005] Conventional directional boring machines operate by connecting the proximal end of a first drill stem to the rotating spindle of the drill head and connecting a drill bit to the opposite or outer (distal) end. With the drill head in a retracted position on the boom, spindle rotation begins and the drill head is advanced axially and distally down the boom resulting in the drilling of a bore. When the drill head reaches the outer (distal) boom end, the proximal end of the drill stem is detached from the drill head spindle and the drill head is retracted to its original position. The proximal end of a second drill stem is then mounted to the spindle with the distal end of the drill stem being connected to the proximal end of the existing first drill stem. The drilling process then continues until the drill head again reaches the distal end of the boom, and the process is repeated.
[0006] The drill stems are typically cylindrical in configuration with hollow interiors to permit the flow therethrough of a drilling lubricant that is discharged through the drill bit at the point of drilling. The drill stems are also relatively rigid, and the bore that is being drilled initially extends linearly at an inclined angle that corresponds to the angle of the boom. The angle of attack of the drilling may be altered so that when a desired depth is reached, the drilling operation is changed to progress generally horizontal, or otherwise parallel with the surface of the ground. When the underground bore has reached its desired length, the drill bit can be directed to be angled upwardly until the drill bit re-emerges at the ground surface. This point of emergence then forms the opposite end of the drilled bore hole or tunnel.
[0007] Many conventional directional boring machines include an electronic transmitter in the drill bit that aids in tracking both the depth and the ground-relative position of the drill bit. After the drill bit re-emerges at the ground surface, a reamer is typically attached to the drill bit which is retracted axially backwardly through the borehole, thus reaming out the borehole to achieve a larger diameter borehole. A utility line is commonly attached to the reamer prior to pulling the drill stem and drill bit back through the borehole so that the utility line or conduit is retracted back through the borehole along with the reamer.
[0008] Due in part to the minimal impact that directional boring machines have on the surrounding environment, directional boring machines have largely replaced other industrial trenching machines (such as back-hoes and power shovels) for laying utility lines, and have reduced the need for such industrial trenching machines. Despite the reduced need for these other trenching machines, many contractors already have amassed a sizable fleet of such equipment. Due to the current preference for new directional boring machines, these open trench-type trenching machines sit idle for a significant percentage of time, thus being significantly under-utilized. Moreover, despite these old style trench-type trenching machines sitting idle for a significant percentage of time, contractors are unable to completely remove them from their fleets, because they are still useful for performing other types of operations, such as excavating basements of houses and other buildings. Accordingly, there is a need for a method and apparatus that enables contractors to better utilize their fleet of industrial machines.
[0009] Directional boring machines currently available in the marketplace typically include treads or wheels that are driven by an on-board engine, thus enabling the directional boring machine to be moved and maneuvered under its own power. Furthermore, these directional boring machines typically include on-board power supplies such as hydraulic pumps or alternators that are driven by the on-board engine. The conventional direction boring machines utilize the on-board power supply both to rotate, tilt and axially move the drill stem and drill bit. Unfortunately, the on-board engine, power supplies, and powered treads or wheels cause conventional directional boring machines to be relatively expensive to acquire or lease. Accordingly, many small contractors simply cannot afford to maintain a fleet of conventional directional boring machines, despite the advantages of directional boring techniques over trench digging techniques.
[0010] Therefore, a need exists for a directional boring apparatus that is less expensive than conventional directional boring machines.
SUMMARY OF THE INVENTION
[0011] In accordance with the present invention, a directional boring device is provided for attachment to a carrier having a power source for providing a first power supply to the boring device for moving the device and a second power supply for operating the device. The boring device comprises an attachment frame, and a selectively attachable first coupler for coupling the attachment frame to the first power supply to permit movement of the device. A drill tool assembly is provided that includes a drill head, a drill stem attachable to the drill head, a drill bit attachable to the drill stem and a drill assembly power transmission. The drill assembly power transmission imparts rotational and axial movement to the drill tool assembly whereby the drill assembly transmission is capable of moving the drill head and drill stem in a path generally parallel to the plane on which the carrier rests. A selectively attachable second coupler is provided for coupling the second power supply to the drill assembly power transmission for permitting the carrier power source to supply power to the drill assembly power transmission to operate the drill tool assembly.
[0012] The present invention addresses the above-identified needs, as well as others, with a directional boring apparatus suitable for being used as an attachment with various new or existing types of carrier bodies such as hydraulic excavators, track-type tractors/dozers, standard wheel loaders, articulating wheel loaders, skid loaders, backhoe loaders, agricultural-type tractors, powered industrial trucks, forklifts, trenching machines, trucks, road graders, and roller compactors. Typical carrier bodies include power units such as steering mechanisms, track assemblies, wheel assemblies, internal combustion engines, transmissions, hydraulic systems, hydraulic pumps, electrical systems, batteries, and alternators.
[0013] By configuring the directional boring apparatus as an attachment that utilizes power supplied by separate powered carrier bodies, the directional boring attachment of the present invention eliminates a large percentage of the components contained in existing self-contained directional boring apparatus and thereby eliminates a large percentage of the cost associated with implementing directional boring technology. Due to the lower cost of implementation, the directional boring attachment of the present invention provides many contractors with access to directional boring technology that would otherwise be too expensive for such contractors to afford. Further, by implementing the directional boring apparatus as an attachment, the present invention provides contractors with a mechanism by which they can better utilize equipment such as open trench-type trenching machines that would otherwise go idle.
[0014] One feature of the present invention is that it has the capability of providing a new method and apparatus for drilling underground bores, which reduces the capital investment required, when compared to known, self-contoured direction boring equipment.
[0015] Additionally, the present invention has the advantage of enabling existing carrier bodies to achieve directional boring capabilities.
[0016] The above and other objects, features, and advantages of the present invention will become apparent to those skilled in the art from the following description and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] [0017]FIG. 1 is a side view of a ground rest-able directional boring attachment that incorporates various features of the present invention;
[0018] [0018]FIG. 2 is a side view of the boring attachment of FIG. 1, absent the axle and wheel assembly of FIG. 1;
[0019] [0019]FIG. 3 is a top view of the ground rest-able directional boring attachment of FIG. 1;
[0020] [0020]FIGS. 4 a and 4 b are side views of a carrier-mounted directional boring attachment embodiment of the present invention;
[0021] [0021]FIG. 5 is a side view of a carrier-mounted embodiment of the present invention;
[0022] [0022]FIG. 5 a is a side view of carrier-mounted supporting frame of the directional boring attachment of the present invention;
[0023] [0023]FIG. 6 is a side view of the ground rest-able embodiment of the present invention, as mounted to an excavator or power shovel;
[0024] [0024]FIG. 7 is a side view of a ground rest-able directional boring attachment of the present invention using an alternate carrier engagement mechanism different than the one shown in FIG. 6;
[0025] [0025]FIG. 8—is a side view of the ground rest-able directional boring attachment of FIG. 7, wherein the boom of the power shovel is in a partially retracted position;
[0026] [0026]FIG. 9 is a side view of a ground rest-able embodiment of the present invention, shown being mounted to a bull dozer-type carrier;
[0027] [0027]FIG. 10 is a side view of a ground rest-able embodiment of the directional boring attachment of the present invention utilizing an alternate coupling mechanism for being coupled to a power shovel;
[0028] [0028]FIG. 11 is a side view of the ground rest-able embodiment of the directional boring attachment of the present invention mounted to a power shovel, with a coupling mechanism slightly different than that shown in FIG. 10, with the wheel and axle assembly attached to the directional boring attachment;
[0029] [0029]FIG. 12 is a side view of the ground rest-able embodiment of the directional boring attachment being illustriously coupled to a track-type dozer;
[0030] [0030]FIG. 13 is a side view of the ground rest-able embodiment of the directional boring attachment of the present invention coupled to a track-type dozer wherein the directional boring attachment has its wheel and axle assembly removed;
[0031] [0031]FIG. 14 is a side view of a track-type dozer and ground rest-able directional boring device of the present invention, showing an alternate, rear-mounted mounting scheme;
[0032] [0032]FIGS. 15 a, 15 b, and 16 are side views of the ground rest-able embodiment of the directional boring attachment of the present invention, that illustrate various mounting schemes for mounting the boring attachment to a wheel loader with FIGS. 15 a and 15 b showing front-mounted mounting schemes; and
[0033] [0033]FIG. 16 illustrating a rear-mounted mounting arrangement.
[0034] [0034]FIGS. 17 and 18 are side view of the ground rest-able embodiment of the directional boring attachment of the present invention being mounted to a Bobcat® brand skid loader showing alternate mounting configurations, wherein FIG. 17 shows a lift-arm mounted mounting configuration, and
[0035] [0035]FIG. 18 shows a “trailer hitch”-type mounting configuration;
[0036] [0036]FIG. 18 a is a side view of another ground rest-able embodiment of the directional boring attachment, wherein the embodiment is shown in a lift arm mounted side positioned embodiment of the directional boring attachment of the present invention coupled to a Bobcat® brand skid loader;
[0037] [0037]FIG. 18 b is a front view of the ground rest-able embodiment of FIG. 18 a, illustrating a front, transversely positioned, ground rest-able mounting arrangement therefor;
[0038] [0038]FIG. 18 c is a side view of the embodiment shown in FIG. 18 b.
[0039] [0039]FIGS. 19 and 20 are side views of the ground rest-able embodiment of the directional boring attachment of the present invention, showing various front (FIG. 19) and rear (FIG. 20) mounting arrangements for mounting the boring attachment to a back hoe-type carrier;
[0040] [0040]FIG. 21 is a side view of the ground rest-able version of the directional boring attachment of the present invention shown as being coupled to an agricultural-type tractor;
[0041] [0041]FIG. 22 is a side view of the ground rest-able embodiment directional boring attachment of the present invention being coupled to a powered industrial truck or fork lift;
[0042] [0042]FIG. 23 is a side view of the ground rest-able version of the directional boring attachment of the present invention coupled to a trench-type carrier;
[0043] [0043]FIGS. 24 a and 24 b illustrate side views of the ground rest-able directional boring attachment of the present invention being mounted to the bed of a lift-bed containing on-road vehicle, such as a truck;
[0044] [0044]FIG. 25 is a side view of the ground rest-able boring attachment of the present invention, being coupled to low grader; and
[0045] [0045]FIG. 26 is a side view of the ground rest-able version of the directional boring attachment being coupled to a roller compactor.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0046] While the invention is susceptible to various modifications and alternative forms, exemplary embodiments thereof have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that there is no intent to limit the invention to the particular forms disclosed. Rather, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
[0047] Referring now to FIGS. 1 - 3 , an exemplary directional boring attachment 20 is illustrated that incorporates various features of the present invention therein. Those of ordinary skill in the art should appreciate that the directional boring attachment 20 is merely exemplary and that the present invention may be advantageously implemented in a wide variety of manners that result in directional boring attachments having components and configurations that differ from those depicted in FIGS. 1 - 3 . For example, the directional boring attachment 20 may be implemented to utilize features of existing directional boring tools such as those described in U.S. Pat. No. 5,944,121 to Bischel et al., U.S. Pat. No. 5,941,320 to Austin et al., U.S. Pat. No. 5,803,189 to Geldner, U.S. Pat. No. 5,778,991 to Runquist et al., and U.S. Pat. No. 4,953,638 to Dunn, the disclosures of which are hereby incorporated by reference.
[0048] As depicted in FIGS. 1 - 3 , the directional boring attachment 20 generally includes a directional boring tool 21 and an attachment frame 22 for holding the various components (discussed below) of the directional boring tool. The attachment frame 22 includes a supporting frame 19 for supporting the attachment frame 22 . The supporting frame 19 is generally used to attach the directional boring tool 21 to various carrier bodies such as such as hydraulic excavators, track-type tractors/dozers, standard wheel loaders, articulating wheel loaders, skid loaders, backhoe loaders, agricultural type tractors, powered industrial trucks, forklifts, trenching machines, trucks, road graders, and roller compactors.
[0049] The attachment frame 22 in an exemplary embodiment comprises a partially open-sided box-like structure comprised of steel tubes that generally define the elongated cuboidal-rectangular shape and structure of the attachment frame 22 . The attachment frame 22 may be further defined or alternatively defined by steel channels, steel beams, and/or equivalent strength materials sized to accommodate the various components of the directional boring tool 21 , attachment yoke 30 , and attachment mechanisms used to attach the directional boring attachment 20 to a particular carrier body. The attachment frame 22 of the embodiment of FIG. 1 includes both longitudinally extending frame members, (e.g. 23 ), vertically extending frame members (e.g. 25 ) and laterally extending frame members (e.g. 35 ).
[0050] When fully assembled, the longitudinally extending 23 , vertically extending 25 and laterally extending 35 frame members create an elongated, rectangular cuboidal box-like attachment frame 22 having a hollow interior for holding a plurality of generally cylindrical drill stems 38 , along with many other of the boring tools 21 components.
[0051] The attachment frame 22 is pivotably coupled at pivot member 17 to a generally horizontally disposed supporting frame 19 , that can also be constructed by a rectangular box array of square or rectangular cross-sectioned tubes. The supporting frame 19 is designed to be strong enough to support the weight of the attachment frame 22 when the support frame is serving as a “trailer” for the attachment frame 22 and associated boring/drill equipment tools 21 , thereon, and also strong enough to withstand the longitudinal and lateral forces exerted on attachment frame 22 when the boring attachment 20 is performing its horizontal drilling.
[0052] The attachment frame 22 generally includes an attachment yoke 30 that includes a pair of upwardly extending reinforced plate members 39 that are attached to the frame members 23 , 25 , 35 of the attachment frame 22 . The plate members 39 each include a large aperture 46 which is aligned with the corresponding aperture of the other plate member 39 .
[0053] The attachment yolk 30 provides a vehicle through which the device 20 can be moved, such as being lifted. In one embodiment, a large pivot pin member (not shown) can be inserted through the aligned apertures 46 , and also through an aperture (not shown) of a carrier body to pivotably connect the attachment yoke 30 (and hence the device 20 ) to the carrier. Alternately, the pin that extends through the aperture can be engaged to a chain whose other end is attached to a movable carrier member (such as the boom of a power shovel) to permit the boom of the carrier to lift the device 20 , otherwise move its geographic position. As another alternative, a chain attached to the carrier body (e.g. power shovel) can be coupled to each of the aligned apertures 46 , to permit the boom of the carrier to lift the device 20 , or otherwise move its geographic position.
[0054] In addition to the large pin (not shown) described above, the attachment yoke 30 can include various other attachment mechanisms 30 such as pins, couplings, hitches, and pivot points that enable the attachment frame 22 and the directional boring attachment device 20 to be attached to the main undercarriage, framework, or other physical attributes of a carrier body.
[0055] As depicted, the attachment frame 22 includes an extendable/retractable coupler 33 that is attached to the supporting frame 19 . The coupler 33 may be designed to be telescoping, as a tube within a tube; or alternately as an angle on an angle. Further, extendable/retractable coupler 33 can be implemented in a rectangular configuration for directly attaching to the undercarriage of a carrier body, or in a triangular configuration when used as a trailer hitch attachment. Preferably the coupler 33 includes an attachment member, such as a female receiver member of a ball hitch, at its distal end 55 for permitting the coupler 33 to be coupled and de-coupled easily to and from an existing trailer mounting member of the carrier. An example of such a trailer mounting member is a common male hitch ball of the type found on many trucks, SUVs, and other vehicles, or a three point hitch member found on agricultural tractors.
[0056] The directional boring tool 21 is carried by the attachment frame 22 which is pivotally coupled to the supporting frame at pivot member 17 . The location of the pivot member 17 (and hence the pivot point and pivot axis) depends upon the size of the attachment frame 22 and directional boring tool 21 and whether an existing hydraulic cylinder (see, e.g. cylinder 70 on FIG. 7) of a carrier body is to be mounted toward the front or the rear of the supporting frame 19 . As will be illustrated, for example, in FIG. 7 an existing cylinder 70 of a carrier body 60 is generally mounted to the attachment frame 22 in order to provide a mechanism for adjusting the angle of attack of the directional boring tool 21 .
[0057] As best shown in FIG. 3, the directional boring tool 21 includes a displacement pump 28 and a hydraulic cylinder or hydraulic motor 29 . The displacement pump 28 generally drives the hydraulic cylinder 29 which applies an axially directed force to a drill head 36 in a forward and reverse axial direction, which in turn provides an axially directed force to a drill stem 38 coupled thereto. The displacement pump 28 provides varying levels of controlled force when thrusting the drill stem 38 into the ground to create a bore and when refractively extracting the drill stem 38 from the bore during a back reaming operation.
[0058] The directional boring tool 21 also includes a rotation pump 30 and a rotation motor 31 . The rotation pump 37 generally drives the rotation motor 31 which provides varying levels of controlled rotation to the drill stem 38 and the drill bit 40 as the drill stem 38 and drill bit 40 are thrust axially forwardly into a bore when operating the directional boring tool 21 in a drilling mode of operation, and for rotating the drill stem 38 and the drill bit 40 when extracting the drill stem 38 and drill bit 40 axially backwardly through the bore when operating the directional boring tool 21 in a back reaming mode. The directional boring tool 21 also includes a coupling drive 41 for advancing and threading individual drill stems 38 together.
[0059] The directional boring tool 21 further includes a control panel or control interface, such as a control panel 32 , that includes a number of manually actuatable switches e.g. 42 , knobs, and levers, e.g. 44 , for manually controlling the displacement pump 28 , rotation motor 31 , motors, and other components that are incorporated as part of the directional boring attachment 20 . The control panel 32 also includes a display including display elements such as gauges 34 , LED's, LCD screens, etc. on which various configuration and operating parameters are displayable to an operator of the directional boring apparatus 20 .
[0060] A wheel assembly 24 can also mounted to the attachment frame 22 , and in particular the supporting frame 19 in order to provide a mechanism for facilitating the transport of the directional boring attachment 20 . In an exemplary embodiment, the wheel assembly 24 is pivotly mounted to the supporting frame 19 in order to allow the wheel assembly 24 to be retracted upwardly and extended downwardly, in a direction indicated generally by arrow A, as needed by a hydraulic cylinder retraction mechanism (not shown). For example, in cases where the weight carrying capacity of a carrier body is limited, the wheel assembly 24 may be extended downward and locked into its ground-engaging position to bear a significant percentage of the device's 20 weight, thereby relieving the carrier body of total vertical support and weight and force bearing responsibilities. In an exemplary embodiment, the wheel assembly 24 is placed just forwardly of the center of gravity toward the front 27 of the directional boring tool 20 to support the directional boring attachment 20 relatively nearer to the front 27 of the supporting frame 19 . However, the physical parameters and location of wheel assembly 24 are dependent upon the size, weight, length, and supported angles of attack of the directional boring device 20 .
[0061] As best shown in FIG. 2, the wheel assembly 24 (FIG. 1) can be designed to be removable. As will be shown in reference to other figures below, certain circumstances exist when the attachment of the wheel assembly 24 to the supporting frame 19 is valuable, but others exist (such as when the device 20 is used in connection with a Bobcat® brand skid loader-type carrier shown in FIGS. 18 b and 18 c ) where the device performs better if placed directly on the ground, with the wheel assembly 24 removed, or fully retracted to a position where the bottom surface of the tires is above the lower, ground-engaging surface of the supporting frame 19 .
[0062] A first stabilizer assembly 26 (FIG. 1) is mounted toward the rear of the attachment frame 22 . The illustrated first stabilizer assembly 26 includes a pair of spaced, adjustable support legs that are locked into a ground-engaging vertical position after positioning the directional boring attachment 20 at a desired drilling site. The first stabilizer assembly 26 helps to stabilize the directional boring attachment 20 during a drilling and reaming operation.
[0063] A second stabilizer assembly 27 (FIGS. 1 and 3) in an exemplary embodiment is mounted toward the front of the rear (distal) end 55 of the supporting frame 19 . The second stabilizer assembly 27 in the exemplary embodiment includes a ground engaging, horizontally disposed plate 43 to which a vertically extending guide pole 45 is attached. The guide pole 45 is generally cylindrical for receiving a vertically extending aperture of a collar 47 which is vertically movable along the guide pole. A rotationally driveable stake driver 49 , is configured for rotatably driving an auger-type stake 51 into and out of engagement with the ground. The engagement of the stake 51 with the ground helps to fixedly position the device 20 , to keep it from moving backwardly or forewardly in response to the axial faces exerted by the drill stem 38 and drill bit 40 as they move, respectively, axially forwardly to drill a bore, and axially backwardly during the reaming of the bore hole.
[0064] Referring now to FIGS. 4 - 11 , several examples of coupling mechanisms are illustrated for coupling the direction boring attachment 20 to an excavator 60 . It is important to note that the directional boring attachment embodiment 54 employs an attachment frame wherein the ground engaging supporting frame, (e.g. 19 ) is replaced with a carrier mountable supporting frame 56 , which is best shown in FIG. 5. In general, the directional boring attachment 20 in FIGS. 4 - 11 is powered, operated and moved by the excavator 60 . In an exemplary embodiment, the directional boring attachment 54 is powered by the hydraulic system of the excavator 60 . Depending upon the requirements of the directional boring attachment 54 and the capacity of the hydraulic system of the excavator 60 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the excavator 60 and the attached directional boring attachment 54 . As is typical of most excavators, the hydraulic lines of the excavator 60 include installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the excavator 60 to the hydraulically driven pumps, motors, and/or cylinders of the directional boring attachment 54 .
[0065] Besides being powered by the hydraulic system of the excavator 60 , the directional boring attachment 54 may alternately be powered by either a power take-off (P.T.O.) of the excavator 60 or be engine shaft driven and located underneath, behind, or in front of the excavator 60 . The directional boring attachment 54 may also be powered by batteries, generators, and/or alternators of the existing electrical system of the excavator 60 . Depending upon the requirements of the directional boring attachment 54 and the capacity of the existing electrical system, one may need to upgrade the electrical system of the excavator 60 with larger batteries, additional batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the excavator 60 and the directional boring attachment 54 .
[0066] In an exemplary embodiment, the directional boring tool 21 and the other controllable features of the directional boring attachment 54 are operated by the control panel similar to control panel 32 that can be mounted inside the existing cab of the excavator 60 and operatively coupled to the directional boring attachment 54 via a wired and/or wireless communications link. Alternatively, the control panel 32 may be mounted upon the directional boring attachment 54 or incorporated into a portable remote unit that is operatively coupled to the directional boring attachment 54 via a wired and/or wireless communications link.
[0067] Examples of a directional boring attachment 20 attached to an excavator 60 are shown in FIGS. 4, 4 a and 5 . In these embodiments, the entire boom assembly 62 of the excavator 60 is unpinned and removed prior to installation of the boring attachment 54 . The attachment frame 56 of the directional boring attachment 54 is then installed and pivotably coupled into place at a pivot point 61 , so that the boring attachment is placed in the same place where the boom assembly was removed from the excavator's 60 main body frame. As best shown in FIG. 5 a, pivot point 51 comprises a laterally extending aperture 61 formed to extend through a vertically disposed main mast mounting bracket 59 that is formed as a part of, and extends downwardly from, the attachment frame 56 .
[0068] As excavators generally do not have standardized parts, the attachment frame 56 of the directional boring attachment 54 will likely need to be custom fitted to each type of excavator that the directional boring attachment is to be coupled to in this manner. More specifically, the dimensional parameters of the attachment frame 56 such as pin placement and pin size depend upon (1) the excavator's dimensions, (2) the size, dimensions, and weight of the directional boring attachment 54 , (3) clearance requirements of the excavator 60 and the directional boring tool 21 , and (4) the angles of attack supported by the directional boring tool 21 .
[0069] Instead of being pivotably coupled to the pivot point 61 of the excavator 60 , the attachment frame 56 may be bolted and/or welded to the carrier frame of the excavator 60 . In an exemplary embodiment, the boom engaging hydraulic cylinders 64 are pivotably pinned to one of the series of apertures 57 of a vertically disposed mounting bracket 58 that is formed as a part of the attachment frame 56 in order to provide a mechanism for controlling the angle of attack for the directional boring tool 21 .
[0070] It should also be noted that the excavator 60 shown in FIG. 5 uses an auger-type 51 ground engaging system, similar to the device 20 shown in FIG. 1. However, the excavation 60 shown in FIGS. 4 a and 4 b employs a ground engaging weighted foot 63 for engaging the front end 43 of the directional boring attachment device 54 to the ground.
[0071] Additional examples of attaching the directional boring attachment 20 to an excavator 60 are illustrated in FIGS. 6 - 7 . In FIGS. 6 and 7, a ground rest-able directional boring attachment 20 , that is generally similar to the attachment 20 shown in FIGS. 1 - 3 , is mounted to the distal end 62 of the boom 66 of the excavator 60 . In the device of FIGS. 6 - 7 , the bucket (not shown) that is normally attached to the distal end 62 of the boom 66 of the excavator 60 is unpinned (de-coupled) and removed. A vertically extending, aperture containing mounting bracket 65 is formed as a part of the attachment frame. The mounting bracket 65 of the attachment frame 22 of the directional boring attachment 20 is then installed and pivotably pinned into place at a pivot point 68 where the bucket (not shown) was removed. As stated above, excavators generally do not have standardized parts. Accordingly, the attachment frame 22 of the directional boring attachment 20 likely needs to be custom fitted and/or fabricated to each type of excavator that the directional boring attachment 20 is to be coupled to in this manner. Again, instead of being pinned to the pivot point 68 of the excavator 60 , the frame 22 may be bolted and/or welded to the pivot point 68 .
[0072] In an exemplary embodiment, the hydraulic cylinders 70 of the boom 66 are pivotably pinned to either the rear mounting bracket 65 (FIG. 6) or the attachment yoke bracket 30 (FIG. 7) of the attachment frame 22 in order to provide a mechanism by which to control the angle of attack for the directional boring tool 21 . The specific size of mounting brackets, sleeves, and locations will vary according to the size of the excavator, the size of the direction boring attachment, and the angle of attack required for the direction boring attachment 20 . Furthermore, the first stabilizer assembly 26 is locked into its ground engaging position to provide further support for the directional boring attachment 20 during operation.
[0073] A further example of attaching the direction boring attachment to the excavator 60 is illustrated in FIG. 8. As illustrated, the directional boring attachment 20 is attached to the excavator's undercarriage framework by the extendable/retractable coupler 33 which may include pins, couplings, and other attachment mechanisms. The bucket (not shown) of the jointed boom assembly 66 is removed from the distal arm 67 , the boom 66 thus creating a pivot point 76 to which the attachment yoke 30 of the direction boring attachment 20 may be pivotably attached.
[0074] In an exemplary embodiment, the distal hydraulic cylinders 70 of distal arm 67 is pivotably coupled to the attachment frame 22 in order to provide a mechanism for controlling the angle of attack of the directional boring tool 21 . Again, the specific size of attachment plates, sleeves, and locations will vary according to the size of the excavator 60 , the size of the direction boring attachment, and the angles of attack supported by the directional boring tool 21 . Further, as depicted in FIG. 8, the first stabilizer assembly 26 may be locked into its ground engaging position to provide further support for the directional boring attachment 20 during operation.
[0075] [0075]FIGS. 10 and 11 illustrate yet further examples of attaching the directional boring attachment 20 to an excavator 60 . As depicted in FIGS. 10 and 11, the rear end 55 of the supporting frame 19 of the attachment frame 22 is attached to the excavator's main undercarriage by the extendable/retractable coupler 33 . The bucket 74 that is pivotably coupled to the distal end of the distal arm 67 is left in place on the boom 66 and used to lift the directional boring attachment 20 via a chain-type sling 69 coupled between a hook (or eye) 71 on the back (non-working) surface of the bucket 74 and an aperture 46 of the attachment yoke 30 of the attachment frame 22 . Further, the bucket 74 may be positioned such that the bucket 74 rests on the attachment yoke 30 of attachment frame 22 for additional weight and stability during the operation of the directional boring tool 21 .
[0076] In an exemplary embodiment, one or more existing hydraulic cylinders (not shown) that are disposed under the excavator 60 are pivotably coupled to the attachment frame 22 in order to provide a mechanism for controlling the angle of attack of the directional boring tool 21 . Again, the specific size of attachment plates, sleeves, and locations will vary according to the size of the excavator 60 , the size of the direction boring attachment, and the angles of attack supported by the directional boring tool 21 . Furthermore, as depicted in FIG. 11, the first stabilizer assembly 26 may be locked into place and the wheel assembly 24 lowered to provide further support for the directional boring attachment 20 during operation. Note also that FIG. 11 illustrates a two chain 69 , 73 sling arrangement, rather than the single chain 69 arrangement shown in FIG. 10. Referring now to FIGS. 10 and 11, it should be noted that FIG. 10 depicts the auger in its raised, or ground-disengaged portion, whereas FIG. 11 depicts the auger 51 in its lowered, ground-engaging and penetrating position
[0077] [0077]FIGS. 9 and 12- 14 illustrate several examples of coupling the exemplary ground rest-able direction boring attachment 20 to a track type tractor/dozer carrier body 100 . In general, the directional boring attachment 20 in FIGS. 9 and 12- 14 is powered, operated and moved by the tractor/dozer 100 . In an exemplary embodiment, the directional boring attachment 20 is powered by the hydraulic system of the tractor/dozer 100 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the tractor/dozer 100 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the tractor/dozer 100 and the attached directional boring attachment 20 . As is typical of most tractor/dozers, the hydraulic lines of the tractor/dozer 100 , power (hydraulic) fluid coupling devices, fluid lines and fluid control devices such as installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the tractor/dozer 100 to the hydraulically driven pumps, motors, and/or cylinders of the direction boring attachment 20 .
[0078] Besides being powered by the hydraulic system of the tractor/dozer 100 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the tractor/dozer 100 and/or engine shaft located underneath, behind, or in front of the tractor/dozer 100 . The directional boring attachment 20 may also be powered by batteries, generators, and/or alternators of the existing electrical system of the tractor/dozer 100 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the existing electrical system of the tractor/dozer 100 , the electrical system may need to be upgraded with larger batteries, additional batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the tractor/dozer 100 and directional boring attachment 20 .
[0079] In an exemplary embodiment, the directional boring tool 21 and the other controllable components of the directional boring attachment 20 are operated by the control panel (see control panel 32 of FIG. 1) that can be mounted in the existing cab 99 (such as on the dashboard) of the tractor/dozer 100 and operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link. Alternately, the control panel 32 may be mounted upon the directional boring attachment 20 (such as shown in FIG. 1) or incorporated into a portable remote unit that is operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0080] In the embodiment shown in FIGS. 12 and 13, the tractor loader bucket or the dozer blade (see 102 at FIG. 14) of the tracker/dozer 100 is unpinned and removed at a pivot point 104 . The directional boring attachment 20 is pivotably attached, by a pivot pin at pivot point 104 to the extendable/retractable coupler 33 which may include pins, couplings, ball-hitches and other attachment mechanisms. As tracker/dozers generally do not have standardized parts, the attachment frame 22 of the directional boring attachment 20 may need custom fabrication or fitting for different types of tracker/dozer that the directional boring attachment 20 is to be coupled to in this manner. More specifically, the dimensional parameters of the attachment frame 22 , such as pin placement and pin size, depend upon: (1) the tracker/dozer's dimensions; (2) the size, dimensions, and weight of the directional boring tool 21 ; (3) clearance requirements of the tracker/dozer 100 and the directional boring tool 21 ; and (4) the angles of attach supported by the directional boring tool 21 .
[0081] Instead of being pivotably coupled by a pivot pin arrangement to the tracker/dozer 100 , the attachment frame 22 may be bolted and/or welded to the pivot point 104 . In the exemplary embodiment shown in FIGS. 9 and 13, the hydraulic cylinders 106 that are normally used for moving the bucket/or blade 102 are pivotably coupled to the attachment frame 22 in order to provide a mechanism by which to control the angle of attack for the directional boring tool 21 . Furthermore, as depicted in FIG. 12, the first stabilizer assembly 26 may be locked into its ground-engaging position and the wheel assembly 24 extended downward to provide further support for the directional boring attachment 20 during operation, thus relieving the tracker/dozer 100 of supporting the entire weight and lateral stresses of the device 20 .
[0082] [0082]FIG. 14 illustrates another example of attaching the directional boring attachment 20 to a track-type tractor/dozer 100 . As illustrated, the back end-placed coupler 33 of the attachment frame 22 is attached to the rear end of the dozer 100 by attachment to the main undercarriage of the tractor/dozer 100 .
[0083] In an exemplary embodiment, existing hydraulic or pneumatic cylinders (not shown) under the tractor/dozer 100 are pivotably coupled to the attachment frame 22 in order to provide a mechanism by which to control the angle of attack of the directional boring tool 21 , by permitting the attachment frame 22 to pivot relative to the supporting frame 19 about the pivot axis formed by pivot 17 . Again, the specific size of attachment plates, sleeves, and locations will vary according to the size and design of the tractor/dozer 100 , the size of the direction boring attachment, and the angles of attack supported by the directional boring tool 21 . Furthermore, as depicted in FIG. 14, the first stabilizer assembly 26 may be locked into its ground-engaging position, and the wheel assembly 24 lowered to provide further support for the directional boring attachment 20 during operation.
[0084] [0084]FIGS. 15 a, 15 b and 16 illustrate embodiments wherein the direction boring attachment 20 is coupled to a standard or articulating wheel loader 150 . In general, the directional boring attachment 20 in FIGS. 15 a, 15 b and 16 is powered, operated and moved by the wheel loader 150 . In an exemplary embodiment, the directional boring attachment 20 is powered by the hydraulic system of the wheel loader 150 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the wheel loader 150 of the wheel loader 150 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the wheel loader 150 and the attached directional boring attachment 20 . As is typical, the hydraulic lines of the wheel loader 150 include hydraulic system components for couveying power (hydraulic) fluid, for controlling the flow of fluid, and for connecting various components together, such as installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the wheel loader 150 to the hydraulic system of the directional boring attachment 20 .
[0085] Besides being powered by the hydraulic system of the wheel loader 150 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the wheel loader 150 and/or engine shaft located underneath, behind, or in front of the wheel loader 150 . The directional boring attachment 20 may also be powered by batteries, generators, and/or alternators of the existing electrical system of the wheel loader 150 and regulated as needed. Depending upon the requirements of the directional boring attachment 20 and the capacity of the existing electrical system of the wheel loader 150 , the electrical system may need to be upgraded with larger batteries, additional batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the wheel loader 150 and directional boring attachment 20 .
[0086] In an exemplary embodiment, the directional boring tool 21 and the other controllable components of the directional boring attachment 20 are operated by a control panel, such as control panel 32 (FIG. 1) that is mounted within the existing cab 152 of the wheel loader 150 and operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link. Alternatively, the control panel 32 may be mounted upon the directional boring attachment 20 in a manner similar to that shown in FIG. 1, or incorporated into a portable remote unit, any of which are operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0087] As illustrated by the example of FIG. 15 b, the bucket or blade 152 (FIG. 15 a ) of the wheel loader 150 is de-coupled by unpinning, and removed at a pivot point 154 prior to the attachment of the directional boring device 20 . The directional boring attachment 20 is attached to the pivot point 154 by the extendable/retractable coupler 33 . As wheel loaders generally do not have standardized parts, the attachment frame 22 of the directional boring attachment 20 may need custom fitting or fabrication for each type of wheel loader that the directional boring attachment 20 is to be coupled to in this manner. More specifically, the dimensional parameters of the attachment frame 22 such as pin placement and pin size depend upon: (1) the dimensions of the wheel loader 150 ; (2) the size, dimensions, and weight of the directional boring tool 21 ; (3) clearance requirements of the wheel loader 150 and the directional boring tool 21 ; and (4) the angles of attack supported by the directional boring tool 21 .
[0088] [0088]FIG. 15 a illustrates a somewhat modified coupling scheme wherein the front end bucket 152 is allowed to remain attached to the loader. The coupler 33 is then coupled to a coupling member, such as a yoke, eye, ball hitch, etc. that is placed on or in the interior of the bucket 152 by the existing bucket 152 mount system of the loader 150 can effect appropriate movement of the boring device 20 . Such movement can either be geographic, to move it along the ground into its desired geographic position, or pivotal movement of the device to establish or change the angle of attachment of the drill tool 21 .
[0089] Returning back to FIG. 15 b, it will be noted that a linkage mechanism is pivotably coupled to extend between a rear mounted mounting bracket 155 that is fixedly coupled to the attachment frame 22 of the boring device 20 , and a hydraulic cylinder attachment point 153 of the loader 150 . The hydraulic cylinders 156 of the bucket/or blade 152 of the dozer are operatively coupled to the attachment frame 22 in order to provide a mechanism for permitting the hydraulic cylinders 156 of the loader 150 to control the angle of attack for the directional boring tool 21 . Furthermore, as depicted in FIG. 15, the first stabilizer assembly 26 may be locked into its ground engaging position and the wheel assembly 24 extended downward and locked into its ground-engaging position to provide further support for the directional boring attachment 20 during operation, thus relieving the wheel loader 150 of total weight and stress support responsibilities.
[0090] [0090]FIG. 16 illustrates another example of attaching the directional boring attachment 20 to a wheel loader 150 . As illustrated, the back end of the supporting arm 19 is attached to a hitch member 157 of the main undercarriage of the wheel loader 150 by the extendable/retractable coupler 33 , in much the same way that a boat trailer is attached to a pick-up truck. In an exemplary embodiment, existing hydraulic cylinders (not shown) under the wheel loader 150 are pivotably coupled to the attachment frame 22 , such as via a connection to a rear-mounted mounting bracket (not shown) in order to provide a mechanism for controlling the angle of attack of the directional boring tool 21 . Again, the specific size of attachment plates, sleeves, and locations will vary according to the size and configuration of the wheel loader 150 , the size of the direction boring attachment, and the angles of attack supported by the directional boring tool 21 . Furthermore, as depicted in FIG. 16, the first stabilizer assembly 26 may be locked into its ground-engaging position and the wheel assembly 24 lowered to provide further support for the directional boring attachment 20 during operation.
[0091] FIGS. 17 - 18 c illustrate examples of coupling the exemplary direction boring attachment 20 to a skid loader 200 . The directional boring attachments 20 , 220 in FIGS. 17 - 18 c are primarily powered, operated and moved by the skid loader 200 . In the exemplary embodiments, the directional boring attachments 20 , 220 are powered by the hydraulic system of the skid loader 200 . Depending upon the requirements of the directional boring attachments 20 , 220 and the capacity of the hydraulic system of the skid loader 200 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the skid loader 200 and the attached directional boring attachments 20 (FIGS. 17 and 18), 220 (FIGS. 18 a - 18 c ). As is typical of most skid loaders, the hydraulic lines of the skid loader 200 , include installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the skid loader 200 to the directional boring attachments 20 , 220 .
[0092] Besides being powered by the hydraulic system of the skid loader 200 , the directional boring attachments 20 , 220 may alternatively be powered by a power take-off (P.T.O.) of the skid loader 200 and/or engine shaft located underneath, behind, or in front of the skid loader 200 . The directional boring attachments 20 , 220 may also be powered by batteries, generators, and/or alternators of the existing electrical system of the skid loader 200 and regulated as needed. Depending upon the requirements of the directional boring attachments 20 , 220 and the capacity of the existing electrical system of the skid loader 200 , the electrical system may need to be upgraded with larger batteries, additional batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the skid loader 200 and directional boring attachments 20 , 220 .
[0093] In an exemplary embodiment, the skid loader includes a partially enclosed cab 205 and a lift arm assembly 206 for lifting and controlling the operation of an attachment such as a bucket 202 (FIG. 18) for excavating and lifting dirt. The lift arm assembly 206 includes a lift arm 207 , a link arm 211 pivotably coupled to each of the lift arm 207 and the skid loader housing 213 , and/or the skid loader's internal components and/or frame (not shown); and also a hydraulically or pneumatically activated cylinder 209 that is pivotably coupled to each of the lift arm 207 and housing 211 , and is provided for moving the lift arm 207 and otherwise controlling its operation.
[0094] In an exemplary embodiment, the directional boring tool 21 and the other controllable components of the directional boring attachments 20 , 220 are operated by a control panel (similar to control panel 32 in FIG. 1) that is mounted at the existing cab of the skid loader 200 and operatively coupled to the directional boring attachments 20 , 220 via a wired and/or wireless communications link. Alternatively, as shown in FIG. 18 a, control panel 232 may be mounted upon the directional boring attachment 220 or incorporated into a portable remote unit that are operatively coupled to the directional boring attachments 20 , 220 via a wired and/or wireless communications link
[0095] As illustrated by the example of FIG. 17, the bucket or blade 202 of the skid loader 200 is unpinned and removed at a pivot point 204 . The directional boring attachment 20 (which is generally similar to the boring attachment 20 of FIG. 1) is pivotably attached to the pivot point 204 by the extendable/retractable coupler 33 . As all skid loaders generally do not have the same standardized parts, the attachment frame 22 of the directional boring attachment 20 may need custom fitting and/or fabrication for each type of skid loader that the directional boring attachment 20 is to be coupled to in this manner. More specifically, the dimensional and design parameters of the attachment frame 22 such as pin placement and pin size depend upon: (1) the dimensions of the skid loader 200 ; (2) the size, dimensions, and weight of the directional boring tool 21 ; (3) clearance requirements of the skid loader 200 and the directional boring tool 21 ; and (4) the angles of attack supported by the directional boring tool 21 .
[0096] Instead of being pivotably coupled by a pivot pin to the pivot point 204 of the skid loader 200 , the attachment frame 22 and/or supporting frame 19 may be bolted and/or welded to the pivot point 204 . In the embodiment of FIG. 17, the hydraulic cylinders (not shown) for the bucket/or blade 202 move the attachment frame 22 by virtue of the connection of lift arm 207 to supporting frame 19 in order to provide a mechanism by which to control the angle of attack for the directional boring tool 21 . In the embodiment of FIGS. 17 and 18, the supporting frame 19 and attachment frame 22 can be fixedly coupled together to move together, as opposed to being movable with respect to each other to change the drill tool attack angle, as in the description of FIG. 1. Alternately, a separate moving member, such as a separately operable hydraulic cylinder (not shown) can be coupled between the skid loader 200 and a mounting bracket, such as attachment yoke 30 , for making the attachment frame 22 movable with respect to the supporting frame 19 about pivot member (and pivot axis) 17 . Furthermore, the first stabilizer assembly 26 may be locked into place, such as is shown in FIG. 1, and the wheel assembly 24 extended downward (also shown in FIG. 1) to provide further support for the directional boring attachment 20 during operation, thus relieving the skid loader 200 of total support and stress responsibilities for the device.
[0097] [0097]FIG. 18 illustrates another example of attaching the directional boring attachment 20 to a skid loader 200 . As illustrated, the back end of the attachment frame 22 is attached to the main undercarriage of the skid loader 200 by the extendable/retractable coupler 33 at the rear of the skid loader. In an exemplary embodiment, existing hydraulic cylinders (not shown) under the skid loader 200 are pivotably coupled to the attachment frame 22 in order to provide a mechanism by which to control and change the angle of attack of the directional boring tool 21 . Again, the specific size of attachment plates, sleeves, and locations will vary according to the size of the skid loader 200 , the size of the direction boring attachment, and the angles of attack supported by the directional boring tool 21 . Furthermore, as depicted, the first stabilizer assembly 26 may be locked into its ground-engaging and the wheel assembly 24 lowered to provide further support for the directional boring attachment 20 during operation.
[0098] Turning now to FIGS. 18 a, 18 b and 18 c, another embodiment 220 of the directional boring attachment is shown. Directional boring attachment 220 is, in most respects, similar to boring attachment 20 , shown in FIG. 1. However, the primary difference between the two different embodiments is that the directional boring attachment 220 of FIGS. 18 a, 18 b and 18 c does not include a separate supporting frame (e.g. 19 ) that is pivotably attachable to the primary support attachment frame (e.g. 22 ). Additionally, the directional boring attachment 20 of FIGS. 18 a - 18 c contains a different support mechanism.
[0099] From an operational and functional standpoint, the directional boring attachment 20 includes generally fewer parts, and is lighter than the directional boring attachment 20 shown in FIG. 1. This lightness can be especially valuable when the directional boring attachment 220 is used with a skid loader, such as skid loader 200 , as the largest number of skid loaders 200 that are manufactured today are relatively small, compact devices that are significantly smaller than traditional power shovel excavators (FIG. 1), bull dozers 100 , power shovels 150 , and other heavy duty earth-working equipment. As these Bobcat® type skid loaders are smaller, they generally have a smaller load capacity than the larger pieces of equipment, thus making the relatively lighter weight directional boring attachment 220 shown in FIGS. 18 a - 18 c especially while suited to these smaller skid loaders.
[0100] Turning now to FIGS. 18 a - 18 c, three different mounting arrangements are shown for mounting the directional boring attachment 220 to the skid loader 200 . It will be appreciated that the skid loader 220 is generally similar to its fellow embodiments, as it is powered, operated and moved by a totally separate, and separable carrier, here, skid loader 200 . The skid loader 220 is preferably powered by the hydraulic system of the separate carrier, such as skid loader 200 , and moved by the hydraulic cylinders and transmission systems of the skid loader 200 . Depending on the requirements of the directional boring attachment 220 and the capacity of the hydraulic system of the skid loader 200 , the hydraulic system of the skid loader (or electrical system if electrically powered) may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, additional regulating equipment, additional batteries, electrical generating equipment (if electrically powered), and additional electrical or hydraulic motive parts, such as electric motors, gear reduction motors (for an electrically operated boring attachments), or hydraulic cylinders (for hydraulically operated directional boring equipment). As is typical of most skid loaders 200 , the hydraulic components of the skid loader 200 include installed tees, valves, quick couplers and additional links of hydraulic lines that facilitate coupling the hydraulic system of the skid loader 200 to the directional boring equipment 220 . Further, the transmission components include an engine, clutch, transmission, drive axles and wheels or tracks.
[0101] In addition to being powered by the hydraulic system of the skid loader 200 , the directional boring attachment 220 may alternatively be powered by a power take off unit of the skid loader, or engine shaft of the skid loader 200 , if such is provided as part of the skid loader 200 .
[0102] The directional boring attachment 220 shown in FIGS. 18 a - 18 c includes a directional boring attachment frame 222 , that includes an integral, and fixedly attached supporting frame 219 for its bottom. The supporting frame portion 219 of the attachment frame 222 is the primary weight-supporting unit, for supporting the weight of the drill tools 221 , including the drill stems 38 . Other members of the boring attachment frame 222 , such as vertically extending members 223 , and laterally extending members 224 provide additional rigidity and strength to the boring attachment frame 222 , and help to position the drill stems 236 on the attachment frame 222 .
[0103] The boring attachment frame 222 also includes a control panel 232 disposed near the forward end of the device. As shown in FIG. 18 a, the control panel 232 includes a plurality of levers 228 for operating the device. Additionally, a plurality of gauges (not shown) or other instrument read-outs (not shown) can be provided.
[0104] As best shown in FIG. 18 a, the supporting structure for supporting the support frame 219 and attachment frame 222 at a proper angle relative to the ground comprises a pair of relatively rearwardly disposed telescoping support legs 226 that are pivotably mounted to the supporting frame 219 at pivot point 230 . Similar to leg 226 of the embodiment shown in FIG. 1, the support leg 230 is movable between a ground-engaging position, as shown in FIG. 18, and a storage position wherein the leg 226 is positioned generally parallel to supporting frame 219 . It will be noted that support leg 226 is a two-piece leg having a lower portion that is sized and configured to be received interiorly, and moved telescopically within the upper portion of the leg 226 .
[0105] A plurality of apertures, e.g. 234 , are formed in the lower leg portion, that are alignable with an aperture 235 of the upper leg portion, and through which a pin or detent means can be inserted to lockingly engage the relative axial positions of the bottom and top portion of the leg 226 . Through this mechanism, the length of leg 226 can be adjusted, so that the attack angle of the boring attachment 220 can be adjusted properly by the user.
[0106] A generally triangular (in cross-section) frontal support frame 227 is disposed under the relatively forward portion of the supporting frame 219 , for supporting the front portion of the attachment frame 222 in a desired spatial and angular relationship to the ground. The triangular support frame 227 includes a ground-engaging leg 231 that is designed to rest on the ground or other surface, an upstanding, vertically disposed leg 229 , and a hypotenuse leg 233 , that extends generally under, and parallel to the supporting frame 219 . If desired, vertical leg 229 can have an adjustable length, to enable the attack angle of the boring attachment 220 to be varied by the user.
[0107] Additionally, one of the structural members of the attachment frame 222 can be fixedly or pivotably coupled to the link arm 211 of the skid loader 200 . This attachment between the link arm 211 and the boring attachment frame 222 will permit the user to adjust the angle of the attack of the drill tool 221 , to a desired attack angle. Additionally, by raising the link arm 211 , the attachment between the link arm 211 and the attachment frame 222 would enable the user to lift the boring tool attachment 220 out upwardly, and out of engagement with the ground to better facilitate the movement of the boring attachment 220 from one location to another.
[0108] Turning now to FIG. 18 b, it will be noted that the boring attachment 222 is shown being coupled to a skid loader 200 , in an arrangement wherein the boring tool attachment 220 is generally disposed in front of, and transversely to the skid loader 200 . In this arrangement, the attachment frame 222 can be fixedly or pivotably coupled to one or both of the lift arms 207 to be permit the user to move the boring attachment 220 upwardly, and out of engagement with the ground, and downwardly, to engage the ground, thereby facilitating movement of the device.
[0109] [0109]FIG. 18 c represents a side view of the embodiment shown in FIG. 18 b. It should be noted that the auger assembly 51 for securing the boring attachment 220 to the ground comprises a pair of spaced augers 51 . Due to the view from which the other drawings are taken, the existence of these two augers may not be clearly represented in the other drawings, and their description. However, the dual auger arrangement shown in FIG. 18 c is a preferred arrangement for all of the auger containing boring attachments of the present invention. As also illustrated in FIG. 18 c, a side mounted mounting bracket 237 is provided for attaching the attachment frame 222 to the lift arm 207 of the skid loader 200 , for facilitating the lifting and movement of the boring attachment 220 by the skid loader 200 .
[0110] FIGS. 19 - 20 illustrate examples of coupling the exemplary ground rest-able directional boring attachment 20 to a backhoe loader 250 . The directional boring attachment 20 in FIGS. 19 - 20 is identical generally to the one shown in FIG. 1, and is primarily powered, operated and moved by the backhoe loader 250 , and is preferably powered by the hydraulic system of the backhoe loader 250 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the backhoe loader 250 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the backhoe loader 250 and the attached directional boring attachment 20 . As is typical of most backhoe loaders, the hydraulic lines of the backhoe loader 250 include installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the backhoe loader 250 to the directional boring attachment 20 .
[0111] Besides being powered by the hydraulic system of the backhoe loader 250 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the backhoe loader 250 and/or engine shaft located underneath, behind, or in front of the backhoe loader 250 . The directional boring attachment 20 may also be powered by batteries, generators, and/or alternators of the existing electrical system of the backhoe loader 250 and regulated as needed. Depending upon the requirements of the directional boring attachment 20 and the capacity of the existing electrical system of the backhoe loader 250 , the electrical system may need to be upgraded with larger batteries, additional batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the backhoe loader 250 and directional boring attachment 20 .
[0112] In an exemplary embodiment, the directional boring tool 21 and the other controllable components of the directional boring attachment 20 are operated by a control panel 32 (similar to FIG. 1 or FIG. 18 a ) mounted in the existing cab 260 of the backhoe loader 250 and operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link. Alternatively, the control panel 32 may be mounted on the directional boring attachment 20 similarly to that shown in FIGS. 1 and 18 a, or incorporated into a portable remote unit that is operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0113] In the embodiment shown in FIG. 19, the bucket or blade 252 of the backhoe loader 250 is unpinned and removed at a pivot point 254 . The directional boring attachment 20 is pivotably attached by a pivot pin to the pivot point 254 by the extendable/retractable coupler 33 , that includes a pivot bracket 255 attached thereto. As backhoe loaders generally do not have standardized parts, the attachment frame 22 and for supporting frame 19 of the directional boring attachment 20 may need custom fitting and/or fabrication for each type of backhoe loader that the directional boring attachment 20 is to be coupled to in this manner. More specifically, the dimensional parameters of the attachment frame 22 such as pin placement and pin size depend upon: (1) the dimensions of the backhoe loader 250 ; (2) the size, dimensions, and weight of the directional boring tool 21 ; (3) clearance requirements of the backhoe loader 250 and the directional boring tool 21 ; and (4) the angles of attack supported by the directional boring tool 21 .
[0114] Instead of being pivotably coupled by a pivot pin to the pivot point 254 of the backhoe loader 250 , the attachment frame 22 may be bolted and/or welded to the pivot point 254 . In an exemplary embodiment, the hydraulic cylinders 256 for the bucket/or blade 252 are pivotably coupled to a mounting bracket 257 of the attachment frame 22 in order to provide a mechanism by which to control the angle of attack for the directional boring tool 21 . Furthermore, as depicted in FIG. 20, the first stabilizer assembly 26 may be locked into its ground engaging position and the wheel assembly 24 extended downward to provide further support for the directional boring attachment 20 during operation, thus relieving the backhoe loader 250 of total support responsibilities.
[0115] [0115]FIG. 20 illustrates another mechanism for attaching the directional boring attachment 20 to a backhoe loader 250 . As illustrated, the extendable/retractable coupler 33 at the back end of the attachment frame 22 is attached to a hitch member 259 , that is coupled to the main undercarriage of the backhoe loader 250 . In an exemplary embodiment, existing hydraulic cylinders (not shown) under the backhoe loader 250 are pivotably coupled to the attachment frame 22 in order to provide a mechanism for controlling the angle of attack of the directional boring tool 21 . Again, the specific size of attachment plates, sleeves, and locations will vary according to the size of the backhoe loader 250 , the size and configuration of the direction boring attachment, and the angles of attack supported by the directional boring tool 21 . Furthermore, as depicted, the first stabilizer assembly 26 may be locked into its ground-engaging position and the wheel assembly 24 lowered to provide further support for the directional boring attachment 20 during operation.
[0116] [0116]FIG. 21 illustrates an example of coupling the exemplary direction boring attachment 20 to an agricultural tractor 300 . The directional boring attachment 20 in FIG. 300 is generally similar to the boring attachment 20 of FIG. 1, and is primarily powered, operated and moved by the agricultural tractor 300 , and, in particular, by the hydraulic system of the agricultural tractor 300 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the agricultural tractor 300 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the agricultural tractor 300 and the attached directional boring attachment 20 . The hydraulic lines of the agricultural tractor 100 (as is typical of most agricultural tractors) include installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the agricultural tractor 300 to the directional boring attachment 20 .
[0117] Besides being powered by the hydraulic system of the agricultural tractor 300 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the agricultural tractor 300 and/or engine shaft located underneath, behind, or in front of the agricultural tractor 300 . The directional boring attachment 20 may also be powered by batteries, generators, and/or alternators of the existing electrical system of the agricultural tractor 300 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the existing electrical system of the agricultural tractor 300 , the electrical system may need to be upgraded with additional batteries, larger batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the agricultural tractor 300 and the directional boring attachment 20 .
[0118] In an exemplary embodiment, the directional boring tool 21 and the other controllable components of the directional boring attachment 20 are operated by a control panel (not shown) which may be similar to control panel 32 of FIG. 1, or control panel 232 of FIG. 18 a, and that can be mounted to the existing cab of the agricultural tractor 300 and operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link. Alternatively, the control panel 32 may be mounted upon the directional boring attachment 20 or incorporated into a portable remote unit that are operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0119] In FIG. 21, the back end of the attachment frame 22 is attached to the main undercarriage of the agricultural tractor 300 by a hitch member 307 that is disposed at the end of the extendable/retractable coupler 33 ; and existing hydraulic cylinders (not shown) under the agricultural tractor 300 are pivotably coupled to the attachment frame 22 in order to provide a mechanism by which to control the angle of attack of the directional boring tool 21 . Again, the specific size of attachment plates, sleeves, and locations will vary according to the size of the agricultural tractor 300 , the size of the direction boring attachment, and the angles of attack supported by the directional boring tool 21 . Furthermore, as depicted, the first stabilizer assembly 26 may be locked into its ground engaging position, and the wheel assembly 24 lowered to provide further support for the directional boring attachment 20 during operation.
[0120] [0120]FIG. 22 illustrates an embodiment wherein the exemplary direction boring attachment 20 is coupled to a powered industrial truck/forklift 350 . In general, the directional boring attachment 20 in FIGS. 22 is powered, operated and moved by the power industrial truck/forklift 350 , and in particular, by the hydraulic and/or pneumatic system of the power industrial tuck/forklift 350 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the power industrial truck/forklift 350 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the power industrial truck/forklift 350 and the attached directional boring attachment 20 . As is typical of most power industrial truck/forklifts, the hydraulic lines of the power industrial truck/forklift 350 , include installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the power industrial truck/forklift 350 to the directional boring attachment 20 .
[0121] Besides being powered by the hydraulic system of the power industrial truck/forklift 350 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the power industrial truck/forklift 350 and/or engine shaft located underneath, behind, or in front of the power industrial truck/forklift 350 . The directional boring attachment 20 may also be powered by the batteries, generators, and/or alternators of the existing electrical system of the power industrial truck/forklift 350 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the existing electrical system of the power industrial truck/forklift 350 , the electrical system may need to be upgraded with additional batteries, larger batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the power industrial truck/forklift 350 and the directional boring attachment 20 .
[0122] In an exemplary embodiment, the directional boring tool 21 and the other controllable components of the directional boring attachment 20 are operated by the control panel 332 , similar to control panels 232 or 32 , that is mounted in the existing cab of the power industrial truck/forklift 350 and operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link. Alternatively, the control panel 32 may be mounted upon the directional boring attachment 20 or incorporated into a portable remote unit that are operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0123] As illustrated in FIG. 22, the attachment frame 22 includes insertion slots 355 that slidably receive and engage the forks 352 of the powered industrial truck/forklift 350 , to thereby couple the fork lift 350 to the attachment frame 22 . By engaging the supporting frame 19 of the attachment frame 22 with the forks 352 , the powered industrial truck/forklift 350 is operable to pick up and lift the entire directional boring attachment 20 in the same way that it normally lifts a pallet. In an exemplary embodiment, the supporting frame is pinned through the forks 352 , and the attachment frame 22 may be chained to the body of the powered industrial truck/forklift 350 . Alternately, the fork 352 of the forklift can be chained to a rearwardly mounted mounting bracket (not shown). Again, the specific size of attachment plates, sleeves, and locations will vary according to the size of the powered industrial truck/forklift 350 , the size of the directional boring attachment 20 , and the angles of attack supported by the directional boring tool 21 . Furthermore, as depicted, the first stabilizer assembly 26 may be locked into its ground-engaging position and the wheel assembly 24 lowered to provide further support for the directional boring attachment 20 during operation
[0124] [0124]FIG. 23 illustrates the direction boring attachment 20 being coupled to, and primarily powered by a trencher 400 . In an exemplary embodiment, the directional boring attachment 20 is powered by the hydraulic system of the trencher 400 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the trencher 400 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the trencher 400 and the attached directional boring attachment 20 . As is typical of most trenchers, the hydraulic lines of the trencher 400 , include installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the trencher 400 to the directional boring attachment 20 .
[0125] Besides being powered by the hydraulic system of the trencher 400 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the trencher 400 and/or engine shaft located underneath, behind, or in front of the trencher 400 . The directional boring attachment 20 may also be powered by batteries, generators, and/or alternators of the existing electrical system of the trencher 400 and regulated as needed. Depending upon the requirements of the directional boring attachment 20 and the capacity of the existing electrical system of the trencher 400 , the electrical system may need to be upgraded with larger batteries, additional batteries, additional alternators, larger alternators, and/or regulated to operate existing equipment of the trencher 400 and directional boring attachment 20 .
[0126] In the embodiment shown, directional boring tool 21 and the other controllable components of the directional boring attachment 20 are operated by the control panel (not shown) that can be mounted in the existing cab of the trencher 400 and operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link. Alternatively, the control panel may be mounted upon the directional boring attachment 20 or incorporated into a portable remote unit that are operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0127] In one embodiment, the trenching tool 402 or backfill blade (not shown) that is attached to powered arm 404 of the trencher 400 is unpinned from coupling point 405 and removed. The directional boring attachment 20 is then pivotably coupled via the extendable/retractable coupler 33 to the undercarriage of the trencher 400 or to the point at which either the trenching tool 402 or backfill blade 404 is removed. As trenchers generally do not have standardized parts, the attachment frame 22 of the directional boring attachment 20 may need custom fitting and/or fabrication for each type of trencher that the directional boring attachment 20 is to be coupled to in this manner. More specifically, the dimensional parameters of the attachment frame 22 such as pin placement and pin size depend upon: (1) the dimensions of the trencher 400 ; (2) the size, dimensions, and weight of the directional boring tool 21 ; (3) clearance requirements of the trencher 400 and the directional boring tool 21 ; and (4) the angles of attack supported by the directional boring tool 21 .
[0128] Instead of being pivotably coupled to the trencher 400 , the attachment frame 22 may be bolted and/or welded to the trencher 400 . In one embodiment, the hydraulic cylinders (not shown) for the trenching tool 402 or the backfill blade 404 are pivotably coupled to the attachment frame 22 in order to provide a mechanism by which to control the angle of attack for the directional boring tool 21 . Furthermore, as depicted in FIG. 23, the first stabilizer assembly 26 may be locked into its ground-engaging position and the wheel assembly 24 extended downward to provide further support for the directional boring attachment 20 during operation, thus relieving the trencher 400 of total support responsibilities.
[0129] [0129]FIGS. 24 a and 24 b illustrate the direction boring attachment 420 being coupled to a vehicle such as a truck 450 . The directional boring attachment in FIGS. 24 a and 24 b is generally similar to directional boring attachment 20 , except that the supporting frame 419 is either fixedly coupled to the truck bed and/or bed frame; or else the supporting frame 419 is a part of the truckbed and/or frame. The boring attachment 420 is powered, operated and moved by the power system of the truck 450 , and in particular, is powered by the hydraulic and/or pneumatic system of the truck 450 .
[0130] Depending upon the requirements of the directional boring attachment 420 and the capacity of the hydraulic system of the truck 450 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the truck 450 and the attached directional boring attachment 420 . As is typical of most trucks, the hydraulic lines of the truck 450 include various hydraulic components such as installed tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the truck 450 to the directional boring attachment 420 .
[0131] In lieu of being powered by the hydraulic system of the vehicle/truck 450 , the directional boring attachment 420 may be powered by a power take-off (P.T.O.) of the truck 450 and/or the vehicle's engine shaft. The directional boring attachment 420 may also be powered by batteries, alternators, and/or generators of the existing electrical system of the truck 450 . Depending upon the requirements of the directional boring attachment 420 and the capacity of the existing electrical system of the truck 450 , the electrical system may need to be upgraded with additional batteries, larger batteries, additional alternators, larger alternators, and/or regulated to operate the existing equipment of the vehicle/truck 450 and the directional boring attachment 420 .
[0132] In an exemplary embodiment, the directional boring tool 421 and the other controllable components of the directional boring attachment 420 are operated by a control panel (not shown) mounted in the existing cab of the truck 450 and operatively coupled to the directional boring attachment 420 via a wired and/or wireless communications link. Alternatively, the control panel (not shown) may be mounted upon the attachment frame 422 of the directional boring attachment 420 or incorporated into a portable remote unit that is operatively coupled to the directional boring attachment 420 via a wired and/or wireless communications link.
[0133] One way in which the directional boring attachment 420 may be attached to the truck 450 is to fixedly couple the attachment frame 422 to the main frame of the truck 450 via the extendable/retractable coupler 33 , and other points of the supporting frame 419 . The attachment frame 422 of the directional boring attachment 420 may need custom fitting for each type of truck 450 that the directional boring attachment 420 is to be coupled to in this manner. More specifically, the dimensional parameters of the attachment frame 422 such as pin placement and pin size depend upon: (1) the dimensions of the truck 450 ; (2) the size, dimensions, and weight of the directional boring tool 421 ; (3) clearance requirements of the truck 450 and the directional boring tool 421 ; and (4) the angles of attack supported by the directional boring tool 421 . Additionally, the rear portion of a lower longitudinal member should be pivotably coupled to the supporting frame 419 to enable the device to pivotably tilt, in a manner similar to a dump-type bed.
[0134] In an exemplary embodiment, the hydraulic lift cylinders 452 of the vehicle/truck 450 are pivotably coupled to the attachment frame 422 in order to provide a mechanism for controlling the angle of attack for the directional boring tool 421 . Furthermore, the first stabilizer assembly 26 may be locked into its ground-engaging position, and the wheel assembly 24 extended downward to provide further support for the directional boring attachment 420 during operation, thus relieving the backhoe loader 250 of total support responsibilities.
[0135] A second way for attaching the directional boring attachment to the truck 450 is to pin the attachment frame 22 to the tilt bed of the truck 450 . Instead of being pinned to the tilt bed of the truck 450 , the attachment frame 422 may be bolted and/or welded to the tilt bed of the truck 450 . The tilt bed provides a mechanism for controlling the angle of attack for the directional boring tool 21 .
[0136] A third means for attaching the directional boring attachment to the truck 450 is to fixedly couple the attachment frame 422 to an isolated center section (not shown) of a flat bed that tilts. Again, instead of pinning the attachment frame 422 to the center section of the flat bed, the attachment frame 422 may be bolted and/or welded to the center section of the flat bed In an exemplary embodiment, the surrounding section of flat bed remains immovable as the center section tilts to afford some angle of attack for the directional boring tool 421 , thus providing a flat working surface for the operator of the directional boring tool 421 . The center section may further include guardrails (not shown) around the direction boring tool 421 and the perimeter of the flat bed to protect the operator of the directional boring tool 421 from injury. The specific size of attachment plates, sleeves, and locations will vary according to the size of the truck 450 , the size of the directional boring tool 421 , and the supported angles of attack. A hydraulic cylinder under the directional boring tool 421 would generally be attached to the secondary attachment frame to perform angle of attack adjustments. In some cases, additional screw type jack supports may be added between the truck's main frame and the frame of the tilt bed to maintain stability and rigidity.
[0137] [0137]FIG. 25 illustrates an example of the directional boring attachment 20 (similar or identical to the boring attachment 20 of FIG. 1) being coupled to a road grader 500 . The directional boring attachment 20 in FIG. 25 is powered, operated and moved primarily by the road grader 500 , and in particular by the hydraulic and/or pneumatic system of the road grader 500 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the road grader 500 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the road grader 500 and the attached directional boring attachment 20 . The hydraulic lines of the road grader 500 include installed hydraulic fluid carriers and fluid flow controllers such as tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the road grader 500 to the directional boring attachment 20 .
[0138] Besides being powered by the hydraulic system of the road grader 500 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the road grader 500 and/or engine shaft. The directional boring attachment 20 may also be powered by batteries, alternators, and/or generators of the existing or supplemental electrical system of the road grader 500 .
[0139] In an exemplary embodiment, the directional boring tool 21 and the controllable components of the directional boring attachment 20 are operated by a control panel mounted either in the existing cab of the road grader 500 or upon the directional boring attachment 20 , or incorporated into a portable remote unit that is operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0140] As illustrated in FIG. 25, the road grader's 500 front blade is unpinned and removed from blade connection member 507 . The attachment frame 22 is then pivotably coupled to connection member 507 . As road graders generally do not have standardized parts, the attachment frame 22 may need to be custom fitted and/or fabricated for each type of road grader that the directional boring attachment 20 is to be coupled to in this manner. More specifically, the dimensional parameters of the attachment frame 22 such as pin placement and pin size depend upon: (1) the dimensions of the road grader 500 ; (2) the size, dimensions, and weight of the directional boring tool 21 ; (3) clearance requirements of the road grader 500 and the directional boring tool 21 ; and (4) the angles of attack supported by the directional boring tool 21 .
[0141] Instead of being pivotably coupled to the road grader 500 , the attachment frame 22 may be bolted and/or welded to the road grader 500 . In an exemplary embodiment, the hydraulic cylinders (not shown) for the front blade are pinned to the attachment frame 22 in order to provide a mechanism by which the angle of attack may be adjusted. Furthermore, the first stabilizer assembly 26 may be locked into its ground-engaging position and the wheel assembly 24 extended downward to provide further support for the directional boring attachment 20 during operation, thus relieving the road grader 500 of total support and stress absorbing responsibilities.
[0142] [0142]FIG. 26 illustrates the exemplary direction boring attachment 20 being coupled to a roller compactor 550 . The directional boring attachment 20 in FIG. 26 is primarily powered, operated and moved by the roller compactor 550 , and specifically by the hydraulic system of the roller compactor 550 . Depending upon the requirements of the directional boring attachment 20 and the capacity of the hydraulic system of the roller compactor 550 , the hydraulic system may need to be upgraded with larger hydraulic pumps, additional hydraulic pumps, and/or regulated to operate the existing equipment of the roller compactor 550 and the attached directional boring attachment 20 . The hydraulic lines of the roller compactor 550 include installed hydraulic system fluid carriers, connectors and fluid flow controllers, such as tees, valves, quick couplers, and additional lengths of hydraulic lines that facilitate coupling the hydraulic system of the roller compactor 550 to the directional boring attachment 20 .
[0143] Besides being powered by the hydraulic system of the roller compactor 550 , the directional boring attachment 20 may alternatively be powered by a power take-off (P.T.O.) of the roller compactor 550 and/or engine shaft located underneath, behind, or in front of the roller compactor 550 . The directional boring attachment 20 may also be powered by batteries, alternators, and/or generators of the existing or supplemental electrical system of the roller compactor 550 .
[0144] In an exemplary embodiment, the directional boring tool 21 and the other controllable components of the directional boring attachment 20 are operated by a control panel (not shown) that is either mounted at the existing cab of the roller compactor 550 ; mounted upon the directional boring attachment 20 ; or else is incorporated into a portable remote unit that is operatively coupled to the directional boring attachment 20 via a wired and/or wireless communications link.
[0145] To attach the directional boring attachment 20 to the roller compactor 550 , the front dozer blade 552 of the roller compactor 550 is first unpinned and removed from attachment point 557 . The attachment frame 22 is then pivotably coupled to attachment point 557 , where the dozer blade was removed. As roller compactors generally do not have standardized parts, the attachment frame 22 may need to be custom fitted and/or fabricated for each type of road grader that the directional boring attachment 20 is to be coupled to in this manner. stead of being pivotably coupled to the roller compactor 550 , the attachment frame 22 may be bolted and/or welded to the roller compactor 550 . In an exemplary embodiment, the hydraulic cylinders (not shown) for the front blade 552 are pivotably coupled to the attachment frame 22 such as at attachment yoke 30 or else to a rear-positioned mounting bracket (not shown) in order to provide a mechanism by which the angle of attack may be adjusted.
[0146] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only exemplary embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. | A directional boring device is provided for attachment to a carrier having a power source for providing a first power supply to the boring device for moving the device and a second power supply for operating the device. The boring device includes an attachment frame, and a selectively attachable first coupler for coupling the attachment frame to the first power supply to permit movement of the device. A drill tool assembly is provided that includes a drill head, a drill stem attachable to the drill head, a drill bit attachable to the drill stem and a drill assembly power transmission. The drill assembly power transmission imparts rotational and axial movement to the drill tool assembly whereby the drill assembly transmission is capable of moving the drill head and drill stem in a path generally parallel to the plane on which the carrier rests. A selectively attachable second coupler is provided for coupling the second power supply to the drill assembly power transmission for permitting the carrier power source to supply power to the drill assembly power transmission to operate the drill tool assembly. | 4 |
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional application Ser. No. 60/294,845 filed May 31, 2001, the disclosure of which is incorporated in its entirety herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to compositions useful for and methods of treating ocular hypertension. More particularly, the invention relates to such compositions and methods which effectively treat ocular hypertension, for example, reduce or at least maintain intraocular pressure and preferably provide enhanced benefits and/or have reduced side effects relative to other compositions and methods.
[0003] Ocular hypotensive agents are useful in the treatment of a number of various ocular hypertensive conditions, such as post-surgical and post-laser trabeculectomy ocular hypertensive episodes, glaucoma, and as presurgical adjuncts.
[0004] Glaucoma is a disease of the eye characterized by increased intraocular pressure. On the basis of its etiology, glaucoma has been classified as primary or secondary. For example, primary glaucoma in adults (congenital glaucoma) may be either open-angle or acute or chronic angle-closure. Secondary glaucoma results from pre-existing ocular diseases such as uveitis, intraocular tumor or an enlarged cataract.
[0005] The underlying causes of primary glaucoma are not yet known. The increased intraocular tension is due to the obstruction of aqueous humor outflow. In chronic open-angle glaucoma, the anterior chamber and its anatomic structures appear normal, but drainage of the aqueous humor is impeded. In acute or chronic angle closure glaucoma, the anterior chamber is shallow, the filtration angle is narrowed, and the iris may obstruct the trabecular meshwork at the entrance of the canal of Schlemm. Dilation of the pupil may push the root of the iris forward against the angle, and may produce pupillary block and thus precipitate an acute attack. Eyes with narrow anterior chamber angles are predisposed to acute angle-closure glaucoma attacks of various degrees of severity.
[0006] Secondary glaucoma is caused by any interference with the flow of aqueous humor from the posterior chamber into the anterior chamber and subsequently, into the canal of Schlemm. Inflammatory disease of the anterior segment may prevent aqueous escape by causing complete posterior synechia in iris bombe and may plug the drainage channel with exudates. Other common causes are intraocular tumors, enlarged cataracts, central retinal vein occlusion, trauma to the eye, operative procedures and intraocular hemorrhage.
[0007] Considering all types together, glaucoma occurs in about 2% of all persons over the age of 40 and may be asymptotic for years before progressing to rapid loss of vision, in cases where surgery is not indicated, topical b-adrenoreceptor antagonists have traditionally been the drugs of choice for treating glaucoma.
[0008] Prostaglandins were earlier regarded as potent ocular hypertensives; however, evidence accumulated in the last two decades shows that some prostaglandins are highly effective ocular hypotensive agents and are ideally suited for the long-term medical management of glaucoma. (See, for example, Starr, M. S. Exp. Eye Res. 1971, 11, pp. 170-177; Bito, L. Z. Biological Protection with Prostaglandins Cohen, M. M., ed., Boca Raton. Fla., CRC Press Inc., 1985, pp. 231-252; and Bito, L. Z., Applied Pharmacology in the Medical Treatment of Glaucomas Drance, S. M. and Neufeld, A. H. eds., New York, Grune & Stratton, 1984, pp. 477-505). Such prostaglandins include PGF 2a , PGF 1a , PGE 2 , and certain lipid-soluble esters, such as C 1 to C 5 alkyl esters, e.g. 1-isopropyl ester, of such compounds.
[0009] In the U.S. Pat. No. 4,599,353 certain prostaglandins, in particular PGE 2 and PGF 2a and the C 1 to C 5 alkyl esters of the latter compound, were reported to possess ocular hypotensive activity and were recommended for use in glaucoma management.
[0010] Although the precise mechanism is not yet known, recent experimental results indicate that the prostaglandin-induced reduction in intraocular pressure results from increased uveoscleral outflow [Nilsson et al., Invest. Ophthalmol. Vis. Sci. 28 (suppl), 284 (1987)].
[0011] The isopropyl ester of PGF 2a has been shown to have significantly greater hypotensive potency than the parent compound, which was attributed to its more effective penetration through the cornea. In 1987 this compound was described as “the most potent ocular hypotensive agent ever reported.” [see, for example, Bito, L. Z., Arch. Opthalmol. 105, 1036 (1987), and Siebold et al., Prodrug 5, 3 (1989)].
[0012] Whereas prostaglandins appear to be devoid of significant intraocular side effects, ocular surface (conjunctival) hyperemia and foreign-body sensation have been consistently associated with the topical ocular use of such compounds, in particular PGF 2a and its prodrugs, e.g. its 1-isopropyl ester, in humans. The clinical potential of prostaglandins in the management of conditions associated with increased ocular pressure, e.g. glaucoma, is greatly limited by these side effects.
[0013] Certain phenyl and phenoxy mono, tri and tetra nor prostaglandins and their 1-esters are disclosed in European Patent Application 0,364,417 as useful in the treatment of glaucoma or ocular hypertension.
[0014] In a series of United States patent applications assigned to Allergan, Inc. prostaglandin esters with increased ocular hypotensive activity accompanied with no or substantially reduced side-effects are disclosed. U.S. Patent Application Ser. No. 386,835 (filed 27 Jul. 1989), relates to certain 11-acyl-prostaglandins, such as 11-pivaloyl, 11-acetyl, 11-isobutyryl, 11-valeryl, and 11-isovaleryl PGF 2a . Intraocular pressure reducing 15-acyl prostaglandins are disclosed in 3 U.S. Ser. No. 357,394 (filed 25 May 1989). Similarly, 11,15- 9,15- and 9,11-diesters of prostaglandins, for example 11,15-dipivaloyl PGF 2a are known to have ocular hypotensive activity. See U.S. Ser. No. 385,645 filed 27 Jul. 1990, now U.S. Pat. No. 4,494,274; 584,370 which is a continuation of U.S. Ser. No. 386,312, and U.S. Ser. No. 585,284, now U.S. Pat. No. 5,034,413 which is a continuation of U.S. Ser. No. 386,834, where the parent applications were filed on 27 Jul. 1989. The disclosures of these patent applications are hereby expressly incorporated by reference.
[0015] Woodward et al U.S. Pat. No. 5,688,819 discloses certain cyclopentane heptanoic acid, 2-cycloalkyl or arylalkyl compounds as ocular hypotensives. These compounds, which can properly be characterized as hypotensive lipids, are effective in treating ocular hypertension. The disclosure of this U.S. Patent is hereby expressly incorporated by reference.
[0016] Timolol maleate ophthalmic solution, for example, sold under the trademark TIMOPTIC® by Merck, is a non-selective beta-adrenergic receptor blocking agent which is indicated in the treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.
[0017] The hypotensive lipids and timolol maleate, when used alone, are effective in treating ocular hypertension. Timolol maleate, when used to control ocular hypertension, may produce one or more disadvantageous side effects, such as headache, fatigue and chest pain, and can have disadvantageous effects on the cardiovascular, digestive, immunologic and nervous systems.
[0018] It would be advantageous to provide for effective, preferably enhanced, treatment of ocular hypertension, preferably with reduced side effects from the treatment employed.
SUMMARY OF THE INVENTION
[0019] New compositions for and methods of treating ocular hypertension have been discovered. The present invention provides for effective treatment of ocular hypertension often using compositions including reduced concentrations of active components. Such compositions and methods have advantageously been found to be surprisingly effective in treating ocular hypertension and/or to reduce the number and/or frequency and/or severity of unwanted side effects caused by timolol components, e.g., timolol maleate, relative to prior art compositions and methods. The present compositions and methods are relatively straightforward, can be easily produced, for example, using conventional manufacturing techniques, and can be easily and conveniently practiced, for example, using application or administration techniques or methodologies which are substantially similar to those employed with prior compositions used to treat ocular hypertension.
[0020] The present methods of treating ocular hypertension comprise applying to an eye an amount sufficient to treat ocular hypertension of a composition comprising a timolol component and a hypotensive lipid component. Each of the timolol component and the hypotensive lipid component is present in the composition in an amount effective to reduce ocular hypertension when applied to a hypertensive eye, that is an eye which has ocular hypertension. The present applying step is effective to treat ocular hypertension, for example, to substantially maintain intraocular pressure or to provide a reduction in intraocular pressure. The present methods preferably provide enhanced treatment of ocular hypertension, for example, enhanced reduction in intraocular pressure, relative to applying a similar composition including either the timolol component or the hypotensive lipid component, but not both, at twice the concentration as in the compositions used in present methods. The present applying step preferably is effective to provide at least one reduced side effect relative to applying a similar composition including the timolol component, but not the hypotensive lipid component, to provide the same treatment of ocular hypertension, e.g., the same reduction in intraocular pressure.
[0021] Without wishing to limit the invention to any particular theory or mode of operation, it is believed that the present compositions and methods take advantage of the different modes of action of the timolol component and the hypotensive lipid component. For example, the timolol component alone is effective, when administered to the eye, to decrease the rate of aqueous humor production. On the other hand, the hypotensive lipid component alone is effective, when administered to the eye, to increase the out flow of aqueous humor from the eye. The combination of a timolol component and a hypotensive lipid component is believed to provide both a decreased rate of aqueous humor production and an increased aqueous humor outflow. This combination of active materials is particularly effective in treating ocular hypotension in one or more specific groups of patients, for example, patients with ocular hypotension which effectively responds to both a reduced rate of aqueous humor production and an increase in aqueous humor outflow.
[0022] The present timolol component/hypotensive lipid component-containing compositions advantageously provide the same or better reduction in intraocular pressure with reduced concentrations of each of these active materials relative to similar compositions including only the timolol component or the hypotensive component. The reduced concentrations of the active materials in the present compositions also reduce the number and/or severity of side effects, in particular side effects caused by the timolol component.
[0023] The timolol component preferably comprises an acid salt of timolol, more preferably comprises timolol maleate. The timolol component is present in the present compositions in an amount effective to reduce intraocular pressure when the composition is applied to a hypertensive eye. The preferred amount of timolol component employed is in a range of about 0.001% to about 1.0% (w/v), more preferably about 0.01% to about 0.2% or about 0.25% or about 0.5% (w/v).
[0024] In one embodiment, the hypotensive lipid component has the following formula (I)
[0000]
[0000] wherein the dashed bonds represent a single or double bond which can be in the cis or trans configuration, A is an alkylene or alkenylene radical having from two to six carbon atoms, which radical may be interrupted by one or more oxide radicals and substituted with one or more hydroxy, oxo, alkyloxy or akylcarboxy groups wherein said alkyl radical comprises from one co six carbon acorns; B is a cycloalkyl radical having from three to seven carbon atoms, or an aryl radical, selected from the group consisting of hydrocarbyl aryl and heteroaryl radicals having from four to ten carbon atoms wherein the heteroatom is selected from the group consisting of nitrogen, oxygen and sulfur atoms; X is a radical selected from the group consisting of —OR 4 and —N(R 4 ) 2 wherein R 4 is selected from the group consisting of hydrogen, a lower alkyl radical having from one to six carbon atoms,
[0000]
[0000] wherein R 5 is a lower alkyl radical having from one to six carbon atoms; Z is ═O or represents 2 hydrogen radicals; one of R 1 and R 2 is ═O, —OH or a —O(CO)R 6 group, and the other one is —OH or —O(CO)R 6 , or R 1 is ═O and R 2 is H, wherein R 6 is a saturated or unsaturated acyclic hydrocarbon group having from 1 to about 20 carbon atoms, or —(CH 2 )mR 7 wherein m is 0 or an integer of from 1 to 10, and R 7 is cycloalkyl radical, having from three to seven carbon atoms, or a hydrocarbyl aryl or heteroaryl radical, as defined above, or a pharmaceutically-acceptable salt thereof, provided, however, that when B is not substituted with a pendant heteroatom-containing radical, and Z is ═O, then X is not —OR 4 . (That is, the cycloalkyl or hydrocarbyl aryl or heteroaryl radical is not substituted with a pendant radical having an atom other than carbon or hydrogen.)
[0025] More preferably the hypotensive lipid component has the following formula II
[0000]
[0000] wherein y is 0 or 1, x is 0 or 1 and x and y are not both 1, Y is a radical selected from the group consisting of alkyl, halo, e.g. fluoro, chloro, etc., nitro, amino, thiol, hydroxy, alkyloxy, alkylcarboxy, halo substituted alkyl wherein said alkyl radical comprises from one to six carbon atoms, etc. and n is 0 or an integer of from 1 to about 3 and R 3 is ═O, —OH or —O(CO)R 6 wherein R 6 is as defined above. Preferably, n is 1 or 2.
[0026] Preferably the hypotensive lipid component has the following formula (III).
[0000]
[0000] wherein hatched lines indicate a configuration, solid triangles are used to indicate β configuration.
[0027] In one embodiment, the hypotensive lipid component has the following formula (IV)
[0000]
[0000] wherein Y 1 is Cl or trifluoromethyl and the other symbols and substituents are as defined above, in combination with a pharmaceutical carrier.
[0028] In a useful embodiment, the hypotensive lipid component has the following Formula (V)
[0000]
[0000] and the 9-and/or 11- and/or 15 esters thereof.
[0029] The hypotensive lipid component is present in the present compositions in an amount effective to reduce intraocular pressure when the composition is applied to a hypertensive eye. The preferred amount of hypotensive lipid component employed is in a range of about 0.00001% to about 0.1% (w/v), more preferably about 0.0001% to about 0.01% (w/v).
[0030] In a further aspect, the present invention relates to pharmaceutical compositions comprising a therapeutically effective amount of a timolol component, and a therapeutically effective amount of a hypotensive lipid component of formulae (X), (II), (III), (IV) or (V) wherein the symbols have the above meanings, or a pharmaceutically acceptable salt thereof, in admixture with a non-toxic, pharmaceutically acceptable liquid vehicle.
[0031] Each and every feature described herein, and each and every combination of two or more of such features, is included within the scope of the present invention provided that the features included in such a combination are not mutually inconsistent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 is a graphical representation of certain effects of a hypotensive lipid/timolol maleate combination on intraocular pressure of laser Induced ocular hypertensive cynomolgus monkeys.
[0033] FIG. 2 is a graphical representation of certain other effects of a hypotensive lipid/timolol maleate combination on intraocular pressure of laser induced ocular hypertensive cynomolgus monkeys.
DETAILED DESCRIPTION OF THE INVENTION
[0034] The present invention relates to the use of combinations of timolol components and lipid hypotensive components as ocular hypotensives in the treatment of ocular hypertension.
[0035] The timolol component is classified as a non-selective beta-adrenergic receptor blocking agent. The chemical name of timolol maleate, a highly preferred timolol component in the present invention, is (-)-1-tert-butylamino)-3-[(4-morpholino-1,2,5-thiodiazol-3 yl) oxy]-2-propanol maleate (1:1) (salt). Other pharmacologically acceptable acid salts may be employed alone or in combination with or without timolol maleate. However, because of its ready availability and its past, known usefulness as an ocular hypotensive, timolol maleate is preferred for use in the present invention. Timolol maleate possesses an asymmetric carbon atom in its structure and preferably is provided as the levo-isomer.
[0036] The preferred amount of timolol component employed is in the range of about 0.001% to about 1.0% (w/v), more preferably about 0.0005% or about 0.01% to about 0.2% or about 0.25% or about 0.5% (w/v), based on the amount of timolol present. To illustrate, each mL of a solution containing 0.25% (w/v) contains 2.5 mg of timolol (3.4 mg of timolol maleate).
[0037] Currently, Merck sells ophthalmic solutions of timolol maleate (under trademark TIMOPTIC® in concentrations of 0.25% (w/v) and 0.5% (w/v). The present compositions and methods preferably employ concentrations of timolol component which are reduced relative to these commercially available materials. It has been surprisingly found that fully acceptable levels of ocular hypertension treatment are achieved with these reduced concentrations of timolol component in combination with the presently useful hypotensive lipid components, also preferably present at relatively reduced concentrations. The reduced amounts of both timolol component and hypotensive lipid component have surprisingly been found to provide enhanced reduction in intraocular pressure when applied to a hypertensive eye relative to applying a similar composition containing twice as much of one, but not both, of the timolol component and the hypotensive lipid component to the hypertensive eye. The relatively reduced amounts of timolol component and hypertensive lipid component advantageously provide at least one reduced side effect when applied to an eye relative to applying a similar composition including one, but not both, of the timolol component and the hypotensive lipid component to an eye to get the same degree of ocular hypotension treatment, for example, the same degree of reduction of intraocular pressure.
[0038] The hypotensive lipid components useful in the present invention are cyclopentane heptanoic acid, 2-cycloalkyl or arylalkyl compounds. These hypotensive lipid components are represented by compounds having the formula I,
[0000]
[0000] as defined above. The preferred nonacidic hypotensive lipid components used in accordance with the present invention have the following formula (II)
[0000]
[0000] wherein the substituents and symbols are as hereinabove defined. More preferably the hypotensive lipid components have the following formula (III)
[0000]
[0000] wherein the substituents and symbols are as defined above. More preferably, the hypotensive lipid components utilized in the present invention have the following formula (IV)
[0000]
[0000] wherein the substituents and the symbols are as defined above.
[0039] Still more preferably the present invention utilizes the hypotensive lipid compounds having the following formula (V)
[0000]
[0000] and their 9- and/or 11- and/or 15-esters.
[0040] In all of the above formulae (I) to (V) for the hypotensive lipid components, as well as in those provided hereinafter, the dotted lines on bonds between carbons 5 and 6 (C-5), between carbons 13 and 14 (C-13), between carbons 8 and 12 (C-8), and between carbons 10 and 11 (C-10) indicate a single or a double bond which can be in the cis or trans configuration. If two solid lines are used that indicates a specific configuration for that double bond. Hatched lines at positions C-9, C-11 and C-15 indicate the a configuration. If one were to draw the p configuration, a solid triangular line would be used.
[0041] In the hypotensive lipid components used in accordance with the present invention, compounds having the C-9 or C-11 or C-15 substituents in the α or β configuration are contemplated. As hereinabove mentioned, in all formulas provided herein broken line attachments to the cyclopentane ring indicate substituents in the a configuration. Thickened solid line attachments to the cyclopentane ring indicate substituents in the β configuration. Also, the broken line attachment of the hydroxyl group or other substituent to the C-11 and C-15 carbon atoms signifies the a configuration.
[0042] For the purpose of this invention, unless further limited, the term “alkyl” refers to alkyl groups having from one to about ten carbon atoms, the term “cycloalkyl”refers to cycloalkyl groups having from three to about seven carbon atoms, the term “aryl” refers to aryl groups having from four to about ten carbon atoms. The term “saturated or unsaturated acyclic hydrocarbon group” is used to refer to straight or branched chain, saturated or unsaturated hydrocarbon groups having from one to about 6, preferably one to about 4 carbon atoms. Such groups include alkyl, alkenyl and alkynyl groups of appropriate lengths, and preferably are alkyl, e.g. methyl, ethyl, propyl, butyl, pentyl, or hexyl, or an isomeric form thereof.
[0043] The definition of RS may include a cyclic component, —(CH 2 ) m R 7 , wherein m is 0 or an integer of from 1 to 10, R 7 is an aliphatic ring from about 3 to about 7 carbon atoms, or an aromatic or heteroaromatic ring. The “aliphatic ring” may be saturated or unsaturated, and preferably is a saturated ring having 3-7 carbon atoms, inclusive. As an aromatic ring, R 7 preferably is phenyl, and, the heteroaromatic rings have oxygen, nitrogen or sulfur as a heteroatom, i.e. R 7 maybe thienyl, furanyl, pyridyl, etc. Preferably m is 0 or an integer of from 1 to 4.
[0044] Z is ═O or represents two hydrogen atoms.
[0045] X may be selected from the group consisting of —OR 4 and —N(R 4 ) 2 wherein R 4 is selected from the group consisting of hydrogen, a lower alkyl radical having from one to six carbon atoms,
[0000]
[0000] wherein R 5 is a lower alkyl radical having from one to six carbon atoms.
[0046] Preferred representatives of the hypotensive lipid components within the scope of the present invention are the compounds of formula V wherein X is —OH, i.e. cyclopentane heptenoic acid, 5-cis-2-(3-αhydroxy-4-m-chlorophenoxy-1-trans-butenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α] and cyclopentane methylheptenoate-5-cis-2 (3-α hydroxy-4-m-chlorophenoxy-1-trans-butenyl)-3,5 dihydroxy, [1α, 2β, 3α, 5α] and the 9- and/or 11- and/or 15-esters of this compound. (The numbered designations in brackets refer to the positions on the cyclopentane ring.)
[0047] The following hypotensive lipid components may be used in the pharmaceutical compositions and the methods of the present invention.
[0048] (1) cyclopentane heptenol-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, (1α, 2β, 3α, 5α)
[0049] (2) cyclopentane heptenamide-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0050] (3) cyclopentane N,N-dimethylheptenamide-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, [1αa, 2β, 3α, 5α]
[0051] ( 4 ) cyclopentane heptenyl methoxide-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0052] (5) cyclopentane heptenyl ethoxide-5-cis-2-(3α-hydroxy-4-meta-chlorophenoxy-1-trans-pentenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0053] (6) cyclopentane heptenylamide-5-cis-2-(3α-hydroxy-4-meta-chlorophenoxy-1-trans-pentenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0054] (7) cyclopentane heptenylamide-5-cis-2-(3α-hydroxy-4-trifluoromethylphenoxy-1-trans-pentenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0055] (8) cyclopentane N-isopropyl heptenamide-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0056] (9) cyclopentane N-ethyl heptenamide-5-cis-2- (3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5 dihydroxy, [1α, 2β, 3α, 5α]
[0057] (10) cyclopentane N-methyl heptenamide-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0058] (11) cyclopentane heptenol-5-cis-2-(3α-hydroxy-4-meta-chlorophenoxy-1-trans-butenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0059] (12) cyclopentane heptenamide-5-cis-2-(3α-hydroxy-4-meta-chlorophenoxy-1-trans-butenyl)-3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0060] (13) cyclopentane heptenol-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)3,5-dihydroxy, [1α, 2β, 3α, 5α]
[0061] A pharmaceutically acceptable salt is any salt which retains the activity of the parent compound and does not impart any deleterious or undesirable effect on the subject to whom it is administered and in the context in which it is administered. With regard to the hypotensive lipid components, such salts are those formed with pharmaceutically acceptable cations, e.g., alkali metals, alkali earth metals, etc.
[0062] The hypotensive lipid components are present in the present compositions in amounts effective to reduce the intraocular pressure of a hypertensive eye to which the composition is applied. Because of the presence of the active timolol component, the amount of hypotensive lipid component employed preferably is relatively reduced, for example, relative to a composition in which the hypotensive lipid component is the only ocular hypotensive with the same intraocular pressure reduction being achieved. Such reduced amounts of hypotensive lipid components utilized in accordance with the present invention preferably provide a reduction in at least one side effect caused by the presence of the hypotensive lipid component. The preferred amount hypotensive lipid component employed is in the range of about 0.00005% to about 1.0% (w/v), more preferably about 0.0001% to about 0.01% or about 0.1% or about 0.5% (w/v).
[0063] Pharmaceutical compositions may be prepared by combining an effective amount of each of a timolol component and a hypotensive lipid component, as active ingredients, with conventional ophthalmically acceptable pharmaceutical excipients, and by preparation of unit dosage forms suitable for topical ocular use.
[0064] For ophthalmic application, preferably solutions are prepared using a physiological saline solution as a major vehicle. The pH of such ophthalmic solutions preferably is maintained between about 4.5 and about 8.0 with an appropriate buffer system, a substantially neutral pH being more preferred but not essential. The formulations may also contain conventional, pharmaceutically acceptable preservatives, stabilizers, surfactants and one or more other conventionally used components.
[0065] Preferred preservatives that may be used in the pharmaceutical compositions of the present invention include, but are not limited to, benzalkonium chloride, chlorobutanol, thimerosal, phenylmercuric acetate phenylmercuric nitrate, chlorite components, such as stabilized chlorine dioxide, and the like and mixture thereof. A preferred surfactant is, for example, Tween 80. Likewise, various preferred vehicles may be used in the ophthalmic preparations of the present invention. These vehicles include, but are not limited to, polyvinyl alcohol, povidone (polyvinyl pyrrolidone), hydroxypropyl methyl cellulose, poloxamers, carboxymethyl cellulose, hydroxyethyl cellulose, cyclodextrin and purified water and combinations or mixtures thereof.
[0066] Tonicity adjusters may be added as needed or convenient. They include, but are not limited to, salts, particularly sodium chloride, potassium chloride, mannitol and glycerin, or any other suitable ophthalmically acceptable tonicity adjustor.
[0067] Various buffers and means for adjusting pH may be used so long as the resulting preparation is ophthalmically acceptable. Accordingly, buffers include acetate buffers, citrate buffers, phosphate buffers, borate buffers and the like and mixtures thereof. Acids or bases may be used to adjust the pH of these formulations as needed.
[0068] In a similar vein, an ophthalmically acceptable antioxidant component may be included in the present composition. Such antioxidant components include, but are not limited to, sodium metabisulfite, sodium thiosulfate, acetylcysteine, butylated hydroxyanisole, butylated hydroxytoluene, and the like and mixtures thereof.
[0069] Other excipient components which may be included in the ophthalmic preparations include, without limitation, chelating agents. The preferred chelating agent is EDTA disodium, although other chelating agents may be used in place of or in conjunction with it.
[0070] The ingredients are usually in the following amounts:
[0000]
Ingredients
Amount (w/%)
Timolol Component
about 0.001-1
Hypotensive Lipid Component
about 0.00005-1
Preservative
0-0.10
Vehicle
0-40
Tonicity adjustor
0-10
Buffer
0.01-10
pH adjustor
q.s. pH 4.5-7.5
antioxidant
as needed
surfactant
as needed
purified water
as needed to make 100%
[0071] The actual doses of the timolol component and hypotensive lipid component used depends on the specific compounds, being employed on the specific condition resulting in the ocular hypertension being treated, on the severity and duration of the ocular hypertension being treated, and the like factors. In general, the selection of the appropriate doses is well within the knowledge of the skilled artisan.
[0072] The ophthalmic formulations of the present invention are conveniently packaged in forms suitable for metered application, such as in containers equipped with a dropper, to facilitate application to the eye. Containers suitable for dropwise application are usually made of suitable inert, non-toxic plastic material, and generally contain between about 0.5 and about 15 ml solution. One package may contain one or more unit doses.
[0073] Especially preservative-free solutions are often formulated in non-resealable containers containing up to about ten, preferably up to about five units doses, where a typical unit dose is in the range of one to about 8 drops, preferably one to about 3 drops. The volume of one drop usually is about 20-35 ul (microliters).
[0074] The invention is further illustrated by the following non-limiting Examples.
EXAMPLES
[0075] Intraocular pressure studies were performed in conscious cynomolgus monkeys, trained to accept pneumatonometry. The animals were restrained for pneumatonometry in custom-designed chairs and given fruit during the experiment.
[0076] A series of four (4) compositions were prepared, by blending the ingredients together. These compositions were as follows:
[0000]
Compositions (A)
Ingredient
1
2
3
4
Hypotensive lipid (B)
0.001%
(w/v)
—
0.001%
(w/v)
—
Timolol Maleate
—
0.05%
w/v
0.005%
(w/v)
—
Polysorbate 80
0.01
(w/v)
0.1%
(w/v)
0.1%
(w/v)
0.1%
(w/v)
Tris Hcl
10
mM
10
mM
10
mM
10
mM
(A) Each composition had a pH of about 7.4 and was an aqueous solution including 0.9% (w/v) of sodium chloride.
(B) The hypotensive lipid was: cyclopentane N-ethyl heptenamide-5-cis-2-(3α-hydroxy-5-phenyl-1-trans-pentenyl)-3,5-dihydroxy, [1α,2β,3α,4α].
[0077] The treatments, coded to the experimenter, were applied topically to the glaucomatous eye as a single 25 μl volume drop, and the normotensive fellow eye received 25 μl of normal saline. The solutions were administered at time 0. Proparacaine (0.1%) was used to provide corneal anesthesia for the intraocular pressure measurements that were performed at one hour before dosing, just before dosing, and then 1, 2, 4 and 6 hours thereafter.
[0078] The mean intraocular pressure (IOP) values for the glaucomatous eyes at time 0 were 40.5 mm Hg for the Composition 1 group, 38.8 mm Hg for the Composition 2 group, 40.6 mm Hg for the Composition 3 group and 39.5 mm Hg for the Composition 4 group.
[0079] IOP mean differences from baseline (DFB) for treated eyes (test DFB) and fellow eyes (fellow DFB) are depicted in FIG. 1 . Test DFB values were statistically significant for the following groups (Student's t-test for paired samples):
[0000]
Compositions
Range (mmHg), p < 0.05
1
−2.0 to −10.3
2
+2.1 to −13.4
3
+2.0 to −19.0
4
+1.0 to −2.3
[0080] The effects of combination treatment with the hypotensive lipid and the timolol component (Composition 3) on IOP of glaucomatous monkeys were compared to each of the other treatments alone (Student's C-test for unpaired samples, p<0.05). The delta-delta values (test DFB—fellow DFB) for the combination treatment (Composition 3) group were significantly lower than those for the hypotensive lipid alone (composition 1) (time=2, 2, 4, 6 hr). The delta-delta values are depicted in FIG. 2 .
[0081] The combination treatment (Composition 3) using relatively low doses of hypotensive lipid and timolol maleate was surprisingly found to be more efficacious in reducing IOP than treatments with either only one of these materials (Compositions 1 and 2) or none of these materials (Composition 4).
[0082] While this invention has been described with respect to various specific examples and embodiments, it is to be understood that the invention is not limited thereto and that it can be variously practiced within the scope of the following claims. | New compositions for and methods of treating ocular hypertension provide for effective treatment of ocular hypertension often using reduced concentrations of active components. Such compositions include a timolol component and a hypotensive lipid component. The present compositions and methods are relatively straightforward, can be easily produced, for example, using conventional manufacturing techniques, and can be easily and conveniently practiced, for example, using application or administration techniques or methodologies which are substantially similar to those employed with prior compositions used to treat ocular hypertension. | 0 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to fasteners, particularly to male fastener components for hook and loop fasteners, to methods of manufacturing them, and to their use in securing a mesh material to a window frame to provide a temporary insect screen.
[0002] It is common, particularly in the United States, to provide windows with permanent screens to allow the windows to be opened without admitting insects. However, such screens are not always provided, and in fact are relatively uncommon in homes in Europe. To meet the need for screening in these situations, temporary screens have been developed. These screens are generally installed when insects are present and removed when insects are not present, by removably attaching a sheet of mesh material to an attachment strip that is adhered to the window frame. Generally these temporary screens are mounted on the inside of the window.
[0003] Attachments strips have been formed of, among other things, the male component of a hook and loop type fastener. To secure the screen, the male fastener elements are inserted through the openings of the mesh material and engage the sides of the mesh openings. It is desirable that the engagement between the male fastener elements and the mesh openings provide good peel strength, so that the screen is not detached by wind, and that the attachment strip be inexpensive and relatively attractive.
[0004] There is also a general need for male fastener components for hook and loop fasteners that provide good multidirectional peel and shear strength properties and that are relatively inexpensive to manufacture.
SUMMARY OF THE INVENTION
[0005] In one aspect, the present invention features a method of forming a fastener. The method includes: (a) forming, from a thermoformable material, a preform product having a sheet-form base and an array of preform stems integrally molded with and extending from the base to corresponding terminal ends; (b) heating the terminal ends of the stems to a predetermined softening temperature, while maintaining the sheet-form base and a lower portion of each stem at a temperature lower than the softening temperature; and (c) contacting the terminal ends with a contact surface that is at a predetermined forming temperature, to deform the terminal ends to form heads therefrom that overhang the sheet-form base.
[0006] Preferred methods include one or more of the following features. The forming temperature is sufficiently low that the thermoformable material does not adhere to the contact surface. The forming temperature is lower than the softening temperature. The contact surface comprises the cylindrical surface of a roll. The contact surface is cooled to maintain the forming temperature during step (c). In step (c), the heads that are formed are substantially disc-shaped or mushroom-shaped. The thickness of each disc-shaped head is from about 5 to 15% of the equivalent diameter of the disc. The head has a substantially dome-shaped surface overhanging the base. Step (a) includes molding the stems in molding cavities in a mold roll. In step (b), the region extends from the terminal end towards the base a distance equal to from about 15 to 25% of the total distance from the terminal end to the base. The contact surface has a surface finish selected from the group consisting of dimpled, smooth, textured, and combinations thereof. The surface finish comprises dimples and the contact surface includes a density of dimples per unit area of the contact surface that is greater than or equal to the density of stems per unit area of the base. During step (c), the dimples are in at least partial registration with the stems.
[0007] In another aspect, the invention relates to a method of forming a fastener, including: (a) forming a plurality of stems, extending from a common base to a terminal end, from a thermoformable material; (b) heating a region of the stems adjacent the terminal ends to a predetermined softening temperature, to soften the material in the region, while maintaining the remaining portion of the stems at a temperature lower than the softening temperature; and (c) contacting the terminal ends with a contact surface to form heads at the terminal end of the stems, at least a portion of the contact surface having a sufficiently rough texture to impart a loop-engaging surface roughness to at least a portion of the heads.
[0008] Preferred methods include one or more of the following features. The contact surface comprises the cylindrical surface of a roll. The contact surface has a sandpaper-like texture. The contact surface has a surface roughness (rugosity) of about 10 to 200 microns. The contact surface defines a plurality of dimples. The contact surface includes a density of dimples per unit area of the contact surface that is greater than or equal to the density of stems per unit area of the base. The surface roughness imparted to the heads is sufficient to increase the peel strength of the fastener by from about 10 to 100%.
[0009] In yet another aspect, the invention features a fastener element including an elongated stem extending and molded integrally with a substantially planar base, and a head disposed at a terminal end of the stem, at least a portion of the head having a rough surface having a sandpaper-like surface texture.
[0010] Preferred fastener elements include one or more of the following features. The rough surface has a surface roughness (rugosity) of from about 10 to 200 microns. The rough surface has sufficient surface roughness to increase the peel strength of the fastener by from 10 to 100%. The head is substantially disc-shaped or mushroom-shaped.
[0011] The invention also features an attachment strip for attaching a mesh screen to a surface. The attachment strip includes (a) a substantially planar base; (b) a plurality of elongated stems extending from the base; and (c) a plurality of heads, each head being disposed at a terminal end of one of the stems. According to one aspect of the invention, at least a portion of the heads have a rough surface having a sandpaper-like surface texture.
[0012] The term “disc-shaped”, as used herein, refers to a shape having top and bottom surfaces, at least a portion of the top surface being substantially parallel to a corresponding portion of the bottom surface, and having a thickness that is substantially less than its equivalent diameter. “Equivalent diameter” means (a) for a circular disc, the actual diameter, and (b) for a disc having a noncircular shape, the diameter of a circular disc having the same thickness and surface area as the non-circular disc. When viewed from above, the disc-shape may be substantially circular, irregular in shape but approximately circular, or non-circular, e.g., square or cross-shaped. The disc-shape may be flat, or may have other shapes such as domed, wavy, or pyramidal.
[0013] The term “mushroom-shaped”, as used herein, refers to any shape having a domed portion, with the exception of a complete sphere.
[0014] The phrase “loop-engaging surface roughness”, as used herein, means a degree of surface roughness that is sufficient to “catch” on a loop fastener element and provide partial, momentary engagement therewith.
[0015] The term “sandpaper-like”, as used herein, means a surface roughness akin to the surface texture of sandpaper.
[0016] The fastener elements of the invention have a head geometry that advantageously provides a strong attachment to a female fastener component. The fastener elements are particularly well adapted for use in fastener tapes for attaching an insect screen to a window frame, as the head geometry provides a strong engagement with the mesh of the insect screen. Insect screen fastener tapes of the invention exhibit good peel strength and thus good resistance to detachment due to wind. The methods of the invention allow the fastener elements to be manufactured using a relatively simple and economical process.
[0017] Other features and advantages will become apparent from the following Description of the Preferred Embodiments, the drawings and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] [0018]FIG. 1 is a side view of a fastener including a fastener element according to one embodiment of the invention.
[0019] [0019]FIG. 1A is a top view of the fastener element, with the stem portion shown in phantom lines.
[0020] [0020]FIGS. 1B, 1C and 1 D are top views of fastener elements according to alternate embodiments of the invention; these fastener elements have the same profile, when seen from the side, as that shown in FIG. 1.
[0021] [0021]FIG. 2 is a side cross-sectional view of a fastener element according to an alternate embodiment of the invention.
[0022] [0022]FIGS. 2A and 2B are top views of fastener elements according to alternate embodiments of the invention; these fastener elements have the same cross-sectional shape as that shown in FIG. 2.
[0023] [0023]FIGS. 3 and 3A are side cross-sectional views of fastener elements according to other alternate embodiments of the invention.
[0024] [0024]FIGS. 3B and 3C are perspective views of fastener elements according to other alternate embodiments of the invention.
[0025] [0025]FIG. 4 is a front view showing a fastener element of FIG. 1 or FIG. 2 engaged with the mesh opening of an insect screen.
[0026] [0026]FIG. 5 is a schematic side view of a machine for manufacturing a fastener element.
[0027] [0027]FIG. 6 is an enlarged view of a portion of the machine shown in FIG. 5.
[0028] [0028]FIG. 7 is an enlarged side detail view of area A in FIG. 6, showing a portion of the stem-carrying base prior to conformation.
[0029] [0029]FIG. 7A is a highly enlarged view of one of the stems shown in FIG. 7.
[0030] [0030]FIG. 7B is a top view of the portion of the base shown in FIG. 7A.
[0031] FIGS. 8 - 8 D are side views showing various suitable conformation roll surfaces for forming fastener elements of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] Referring to FIG. 1, fastener 10 includes a base 12 and a fastener element 14 extending from the base. (Fastener 10 generally includes an array of fastener elements; a single fastener element is shown for clarity.) Fastener element 14 includes a stem 16 and, at the terminal end of stem 16 , a head 18 . Head 18 is shaped for engagement with another fastener component, for example a female fastener component having a plurality of loops, a mesh such as an insect screen, or another fastener component similar to fastener 10 .
[0033] As shown in FIG. 1, head 18 is substantially disc shaped, including a substantially planar top surface 20 , and a substantially planar bottom surface 22 that faces and overhangs base 12 . It is desirable that the disc be relatively thin, allowing a cooperating fastener element, e.g., a loop or the wire mesh of a window screen, to penetrate into the disc by flexing the disc material. Preferably, the thickness of the disc is from about 5 to 15% of the equivalent diameter of the disc. If the disc is thinner, it will tend to have reduced cycle life (i.e., durability during repeated engagement and disengagement of the fastener), whereas if the disc is thicker the fastener may exhibit reduced peel strength. As shown in FIG. 1A, head 18 is substantially circular when viewed from above, and stem 16 is substantially square in radial cross-section. (In other embodiments, head 18 can be irregular in shape (FIG. 1B), square (FIG. 1C) or cross-shaped (FIG. 1D) when viewed from above.) The disc shape is particularly advantageous for engagement with a mesh screen 23 (FIG. 4) because the sides 25 of the mesh opening can penetrate into the thin disc. As a result, as shown in FIG. 4, secure engagement can be provided even though the disc is smaller than the mesh opening and only engages one or two sides 25 of the mesh opening. The head 18 is also suitable for engagement with loops or with other similarly shaped heads.
[0034] In an alternate embodiment, shown in FIG. 2, head 18 includes a domed portion 24 , and a correspondingly dome-shaped lower surface 23 , a major portion of which is substantially parallel to domed portion 24 . Surface 23 faces and overhangs base 12 , providing a surface for engagement with a female fastener element or mesh. Head 18 can have various shapes. For example, head 18 can be a disc that is square or rectangular when viewed from the top (FIG. 2A), with two opposed edges of the disc being bent down to form a U-shaped domed portion. Alternatively, head 18 can be a circular disc that is bent down around its periphery to form a mushroom-like domed portion. These head shapes are particularly advantageous for engagement with a mesh screen (FIG. 4) because the domed portion allows smooth penetration into the mesh openings 27 and the thin disc shape allows sides 25 of the mesh opening to be embedded into surface 23 . Head 18 can also be used to engage the loops of a female fastener component, or to self-engage with another fastener having similarly shaped heads.
[0035] In alternate embodiments, shown in FIGS. 3 and 3A, the disc-shaped heads are “wavy”. The head 18 may be S-shaped in cross-section, as shown in FIG. 3, or may be W-shaped, as shown in FIG. 3A. The head shapes shown in these figures may be provided with a rough surface, as described below with reference to FIG. 3B.
[0036] In another alternate embodiment, shown in FIG. 3B, head 18 includes a rough, sandpaper-like surface 30 . Preferably, the texture of surface 30 resembles that of 320 grain sandpaper (used for sanding metals). The sandpaper-like surface includes protrusions that tend to catch on the fastener component with which the head 18 is engaged (not shown), making it more difficult to inadvertently disengage the mated fastener components. As a result, the strength of engagement is generally increased, relative to the strength obtained from a similar fastener element having a smooth surface. In particular, in preferred embodiments the peel strength, as measured by ASTM D 5170-91 (“T” method), is increased by about 10 to 100%. It is preferred that the surface 30 have a surface roughness (rugosity) of at least 10 microns, more preferably from about 10 to 200 microns.
[0037] In another embodiment, shown in FIG. 3C, the head 18 pyramidal in shape. Preferably, the surface of the head that overhangs the base has the same contour as the upper surface of the head, so that a major portion of the surfaces is substantially parallel.
[0038] In all of the embodiments shown in FIGS. 1 - 3 C, the head overhangs the base to a significant extent. Preferably, the surface area A1 of the surface overhanging the base is equal to at least 20% greater than the surface area A2 of the radial cross-section of the stem 16 taken along line A-A, i.e., where the stem intersects the head. The surface area A1 may be up to 600% greater than the surface area A2. For example, for a fastener element in which surface area A2 is 0.03 mm 2 , surface area A1 is preferably about 0.05 mm 2 . It is also generally preferred that the amount of overhang be substantially uniform around the perimeter of the stem, to provide a multi-directional engagement. However, for ease of manufacture it will in some cases be preferred that the amount of overhang be non-uniform, as will be discussed below with reference to FIG. 5.
[0039] A machine 100 for forming the fastener elements described above is shown in FIG. 5. A supply roll 102 introduces a continuous supply of a stem-carrying base 12 (shown in FIGS. 7 - 7 B) into the machine 100 . Stem-carrying base 12 is formed of a thermoformable polymer. In a previous manufacturing step, roll 102 was wound up as the take-up roll at a molding station (not shown) at which stems 104 (FIGS. 7 - 7 B) were integrally molded onto base 12 . The molding station may include a mold roll having a plurality of mold cavities provided by aligned plates, e.g., as described, for example, by U.S. Pat. No. 4,794,028, the disclosure of which is incorporated herein by reference, or may utilize any desired stem-molding technique. As shown in FIG. 7B, the stems may be square in radial cross-section, if a square head is desired, or may be oval, round, cross-shaped, or any other desired shape, for forming similarly shaped heads (see FIGS. 1 A- 1 D).
[0040] The supply roll 102 is unwound by drive mechanism 106 , which conveys stem-carrying base 12 into optional preheating area 108 which raises the temperature of the stem-carrying base 12 to a pre-heat temperature that is above room temperature but much lower than the Vicat temperature of the polymer. This pre-heating allows the tips of the stems to be heated to a predetermined softening temperature more quickly during the next step of the process.
[0041] Next, the base 12 moves to heating device 110 , which heats a portion of the stems. As indicated in FIG. 7A, only a portion P of the stems 104 , adjacent their tips 109 , is heated by heating device 110 , leaving the remainder of the stem relatively cool and thus relatively rigid. Preferably, the length L of portion P is less than 30% of the total length L1 of the stem, more preferably from about 15% to 25% of L1. Portion P is heated to a softening temperature at which portion P can be formed into a desired head shape, typically a temperature that is greater than or equal to the Vicat temperature of the thermoformable polymer. The remainder of the stem is not heated, and remains at a temperature that is less than the softening temperature S, preferably at least 10% less.
[0042] To ensure that only portion P is heated to the softening temperature, it is preferred that heating device 110 include a non-contact heat source 111 (FIG. 6) that is capable of quickly elevating the temperature of material that is very close to the heat source, without raising the temperature of material that is relatively further away from the heat source. Suitable non-contact heat sources include flame heaters, electrically heated nichrome wire, and radiant heater blocks. To heat portion P to the softening temperature without contact, the heat source typically must be at a relatively high temperature. For example, if the softening temperature is from about 100 to 140° C., the temperature of the heat source will generally be from about 300 to 1000° C. and the heat source will be positioned from about 0.1 to 30 mm from the tips of the stems.
[0043] After portion P of the stems has been heated, the base 12 moves to conformation head 112 , at which base 12 passes between conformation roll 114 and drive roll 116 . Conformation roll 114 forms the portion P of the stems into a desired head shape, as will be described in further detail below, while drive roll 116 advances base 12 and flattens it against roll 114 to enhance head uniformity. It is preferred that the temperature of conformation roll 114 (the forming temperature) be lower than the softening temperature. Maintaining the conformation roll 114 at this relatively low temperature has been found to allow the conformation roll to flatten the spherical (“ball-shaped”) heads that are generally formed during the previous heating step into a desired head shape. Spherical heads are generally undesirable, as such heads tend not to provide secure engagement with a mating fastener. A low forming temperature also prevents adhesion of the thermoformable polymer to the conformation roll. Generally, to obtain the desired forming temperature it is necessary to chill the conformation roll, e.g., by running cold water through a channel 115 in the center of the roll, to counteract heating of the conformation roll by the heat from portion P of the stems. If further cooling is needed to obtain the desired forming temperature, the drive roll may be chilled in a similar manner.
[0044] The surface texture of conformation roll 114 will determine the shape of the heads that are formed. If disc-shaped heads having a smooth surface are desired, the surface texture will be smooth and flat. If a sandpaper-like surface is desired, the surface texture of the conformation roll will be sandpaper-like (FIG. 8). If mushroom-shaped (domed) heads are desired, the conformation roll will include a plurality of substantially hemispherical indentations (“dimples”) to form the dome portion of the heads (FIG. 8A). Disc-shaped heads having a “wavy” shape, e.g., as shown in FIGS. 3 and 3A, can be formed using the conformation roll surfaces shown in FIGS. 8B and 8C. The diamond-lattice conformation roll surface shown in FIG. 8D will give the head a pyramidal shape, e.g., as shown in FIG. 3C. The conformation roll may also have a soft surface (not shown), e.g., rubber, to provide a mushroom-shaped head.
[0045] Preferably, when the surface texture includes dimples, the density of the dimples is substantially uniform over the roll surface, and is greater than or equal to the density of stems on the base 12 . To allow for improper registration between the stems and the dimples, it is preferred that the density of the dimples be substantially greater than the density of the stems (if the density is equal, improper registration may result in none of the stems being contacted by dimples).
[0046] As discussed above, while the uniformly overhanging, domed head shape shown in FIG. 2 is generally preferred, obtaining this shape may unduly complicate manufacturing, due to the need to maintain substantially complete registration between the dimples and stems. As a result, for ease of manufacturing it may in some cases be desirable to form less uniform head shapes by allowing the dimples and stems to be in partial registration, rather than full registration. In these cases, the conformation roll should have a density of dimples that is significantly higher than the density of stems, to increase the probability of contact between the dimples and stems. In this manner, some of the heads are likely to have the shape shown in FIG. 2, while other heads will have different head shapes resulting from contact of a stem with a portion of a dimple.
[0047] The spacing of the conformation roll 114 from the drive roll 116 is selected to deform portion P of the stems to form the desired head shape, without excessive damage to the unheated portion of the stems. It is also preferred that the spacing be sufficiently small so that the drive roll flattens base 12 and provides substantially uniform contact pressure of stem tips 109 against the conformation roll. Preferably, the spacing is approximately equal to the total height of the stem (L1, FIG. 7A) less the length of the heated portion P (L, FIG. 7A).
[0048] Next, the base 12 moves to a cooling station 118 . Cooling station 118 cools the formed heads, e.g., by cool air, preventing further deformation of the heads. Preferably, the heads are cooled to approximately room temperature. The cooled base is then moved through driving station 120 and wound onto take-up roll 122 by winding element 124 .
[0049] Alternate supply and take-up rolls 126 , 128 are provided so that when supply roll 102 is depleted and/or when take-up roll 124 is filled, the appropriate roll can be easily replaced without disrupting the process.
[0050] Suitable materials for use in forming the fastener are thermoplastic polymers that provide the mechanical properties that are desired for a particularly application. Preferred polymers include polypropylenes, such as those available from Montell under the tradename MOPLEN, polyethylenes, ABS, polyamides, and polyesters (e.g., PET).
[0051] Other embodiments are within the claims.
[0052] For example, while disc-shaped heads have been shown and discussed above, the head may have any desired shape that provides a surface overhanging the base to an extent sufficient to provide a multi-directional engagement having desired strength characteristics.
[0053] Moreover, while the process described includes only a single heating of the stem tips and a single pass through a conformation head, these steps may be repeated one or more times to provide other head shapes. Subsequent conformation heads may have the same surface as the first conformation head, or may have different surfaces.
[0054] In addition, if desired the stem tips may be cooled after the heating step and immediately before the conformation head, to form a spherical head that is then forced down against the stem, embedding the upper portion of the stem in the head to form a mushroom-shaped head.
[0055] Further, in some cases it is not necessary to cool the conformation roll. If the desired head shape can be obtained and resin sticking can be avoided, the conformation roll may be used without either heating or cooling, or may be heated. | A method of forming a fastener is provided, including (a) forming, from a thermoformable material, a preform product having a sheet-form base and an array of preform stems integrally molded with and extending from the base to corresponding terminal ends; (b) heating the terminal ends of the stems to a predetermined softening temperature, while maintaining the sheet-form base and a lower portion of each stem at a temperature lower than the softening temperature; and (c) contacting the terminal ends with a contact surface that is at a predetermined forming temperature, lower than the softening temperature, to deform the terminal ends to form heads therefrom that overhang the sheet-form base. Fasteners and other methods of forming them are also provided. | 8 |
REFERENCE TO RELATED APPLICATIONS
This application is a national stage application under 35 USC 371 of International Application No. PCT/GB2005/001564, filed Apr. 25, 2005, which claims the priority of United Kingdom Application No. 0410699.3, filed May 13, 2004, the contents of both of which prior applications are incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a tool for a surface treating appliance, such as a vacuum cleaner.
BACKGROUND OF THE INVENTION
Vacuum cleaners are typically of the upright or cylinder type. Cylinder cleaners consist of a main body containing a motor and fan unit for drawing an airflow into the main body and separating apparatus for extracting dirt and dust from the airflow and retaining it for disposal. The separating apparatus can be a cyclonic arrangement, bags, filters or a combination of these. A hose and wand assembly is connected to the inlet of the main body. A floor tool having a suction opening is attached to the end of the wand remote from the main body so that the suction opening can be manoeuvred across the surface to be cleaned by the user. Upright cleaners commonly have a cleaner head permanently attached to the main body of the vacuum cleaner which is manoeuvred, together with the main body, across the surface to be cleaned. However, many upright cleaners can also be operated in the manner of a cylinder machine by having a removable or releasable hose and wand assembly provided to which an accessory such as a floor tool can be attached.
Conventional floor tools typically comprise a housing which defines a downward-facing suction opening and in which is arranged a driven agitator in the form of a brush bar or beater, for example. Dirt and dust is dislodged from the carpet or other floor covering by the rotating brush bar or beater and the dirt and dust is drawn into the cleaner head by virtue of the suction produced by the downstream fan. Dirt laden air is then passed to the separation apparatus before clean air is expelled to the atmosphere.
A problem which may be encountered with such floor tools is that they may become blocked by small objects drawn by suction from the floor surface. Threads, fibres and hairs can also become entangled around the agitator, thereby jamming it. A user of the appliance needs to be able to access the interior of the tool to remove the blockage.
SUMMARY OF THE INVENTION
The invention provides a tool for a surface treating appliance comprising a housing, an agitator in the housing and a suction opening, in which the agitator is removable through the suction opening.
The provision of an agitator that is releasable through the suction opening greatly simplifies removal of the agitator for the purposes of clearing the floor tool of blockages or for replacement of the agitator.
Preferably, a catch is provided for releasing the agitator from its usual position in the housing. The catch may be activated by means of a lever, which also assists the user by producing a pivoting movement to remove the agitator from its position in the housing.
Advantageously, a flange is provided, in which the agitator is movably located. The lever may be arranged to act on the flange for removing the agitator. The flange may be an end cap in which the agitator is movably arranged. Part of the flange may form a pivot point with a region of the housing, such as a sole plate, for easy pivoting release of the agitator.
In accordance with another embodiment of the invention, a portion of the housing is removable so that a user can access the interior of the tool to remove blockages, especially those occurring in the neck of the tool. Preferably, this portion is releasable from the remainder of the housing against the force of resilient means.
At least a portion of the housing is transparent so that the user can see any blockages within the tool.
The agitator may comprise a brush bar or beater, which may be rotatably driven by means of a turbine.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, by way of example, with reference to the accompanying drawings, in which:—
FIG. 1 is a perspective view of a tool constructed according to the invention;
FIGS. 2 a and 2 b are perspective views from underneath of the tool of FIG. 1 , showing removal of the agitator;
FIG. 3 is a perspective view from underneath of the tool of FIGS. 1 , 2 a and 2 b , showing removal of a portion of the housing; and
FIG. 4 is a perspective view from underneath of the tool of FIGS. 1 , 2 a , 2 b and 3 with the agitator and a portion of the housing removed.
Like reference numerals refer to like parts throughout the specification.
DETAILED DESCRIPTION OF THE INVENTION
The drawings show a floor tool for a vacuum cleaner, indicated generally by the reference numeral 1 . The floor tool 1 has a head 2 formed by a housing 3 which has a suction opening 4 formed in the lower surface thereof. Part of the housing is transparent so that the user can view blockages in the tool 1 . The floor tool 1 also includes a neck 5 , which has a forward portion 6 and a rearward portion 7 . The forward portion 6 carries two wheels 8 and is connected to the head 2 via a rotatable coupling 9 . The rearward portion 7 has a collar 10 for receiving a wand or hose attached to the main body of the vacuum cleaner with which the floor tool 1 is to be used. A catch 11 may be provided on the rearward portion 7 for the purpose of retaining the hose or wand on the collar 10 .
Referring to FIGS. 2 a and 2 b , a sole plate 12 is provided for engaging with the floor surface. The sole plate 12 may be fixed with respect to the housing 3 or may be pivotable to ensure that the sole plate keeps in intimate contact with irregular floor surfaces.
An agitator in the form of a brush bar 13 is rotatably supported in the housing 3 immediately above the suction opening 4 . The brush bar 13 is located such that bristles or beaters carried by the brush bar project through the suction opening 4 as the brush bar rotates and agitate the surface to be cleaned. The brush bar 13 is shown in these drawings without bristles for the purposes of clarity. Ordinarily, a plurality of clusters of bristles are mounted onto a cylindrical core. The clusters of bristles are typically mounted in a helical formation at regular intervals around the entire circumference of the core and along its entire length or the majority thereof. The brush bar 13 is rotatably driven by means of a turbine 14 , through which air is drawn by the motor of the vacuum cleaner, and a drive belt (not shown).
In accordance with the invention, the brush bar 13 is removable through the suction opening 4 . Thus, a user can readily clear blockages in the floor tool 1 , remove material that is tangled up in the bristles or else easily replace a worn brush bar.
A lever arm 15 is provided in order to facilitate removal of the brush bar 13 . In this embodiment, the lever arm 15 forms part of one of the sides 16 of the sole plate and is integral with an end cap 17 . The end cap 17 comprises one of a pair of end caps 17 , 18 in which the end portions of the brush bar 13 are located in the housing 3 . The other end cap 18 locating an end portion of the brush bar 13 is fixed to, or an integral part of, the housing 3 of the tool.
In use, the user applies a turning moment to the free end of the lever arm 15 . The arm 15 is made from a resilient material, such as plastic. Thus, the force applied to the lever arm 15 causes it to flex slightly, thereby releasing a catch (part 19 of which is visible in these drawings) holding the end cap 17 in place in the housing 3 . The end cap 17 is freed from its location in the housing 3 . The user can continue to apply a turning moment to the lever arm 15 in the direction of the arrow. A notch 20 is provided in the end cap 17 , which notch co-operates with a region 21 of the front of the sole plate to provide a suitable point about which to pivot the end cap. Thus, the end cap 17 is released from the housing 3 through the suction opening 4 . The user then simply slides the other end portion of the brush bar 13 out of its respective end cap 18 in the housing 3 through the suction opening 4 . Thus, the brush bar arrangement comprising the brush bar 13 itself, the end cap 17 and the lever arm 15 is released from the tool 1 entirely through the suction opening 4 . The brush bar 13 is easily removed from the end cap 17 , if required.
In order to replace the brush bar arrangement, the user simply reverses this operation. One end portion of the brush bar 13 is placed in the end cap 18 that forms part of the housing 3 . The other end portion of the brush bar 13 slots into the removed end cap 17 , which is introduced to the housing 3 by engaging the notch 20 in the region 21 of the sole plate 12 and pivotably moving the end cap towards the housing accordingly. The member comprising the end cap 17 and lever arm 15 is arranged to fit into the housing 3 in a snap fit manner, so that the user can simply push the brush bar arrangement back into position. Alternatively, the arm 15 or the end cap 17 may have a spring clip or other fastener for holding the brush bar 13 in the housing 3 in normal use.
Additionally, the user may need to gain access to a narrow opening 22 in the neck 5 of the floor tool. The cross-sectional area of the opening 22 in the neck 5 is less than that of the suction opening 4 . Therefore, large particles of debris and other objects can become blocked in this opening 22 . In accordance with an alternative embodiment of the invention, a portion 23 of the housing is removable from the floor tool 1 , as shown in FIG. 3 .
In this embodiment, the removable portion 23 of the tool 1 comprises the front lower portion, which portion includes a transparent region and the sole plate 12 of the tool. The lower portion 23 of the tool includes an end face 24 which is normally behind one side wall 25 of the upper portion 26 of the tool. The end face 24 of the removable portion 23 has a collar 27 which is located in an aperture 28 on the side wall 25 . The collar 27 may be arranged to hold the lower portion 23 in a fixed relationship with respect to the upper portion 26 , or may provide a predetermined amount of relative pivoting movement to keep the sole plate 12 in intimate contact with irregular floor surfaces in use.
Both the upper 26 and lower 23 portions of the floor tool 1 are of plastics materials having a certain degree of flexibility. Thus, in order to release the lower portion 23 , the user urges the portions of the tool 1 to flex apart with respect to each other. The most straightforward manner of achieving this with the illustrated embodiment is to depress the collar 27 located in the aperture 28 on the side wall 25 so that it pops out of the aperture. Thus, the lower portion 23 including the transparent region and the sole plate 12 can be pulled out of the housing 3 . The removable portion 23 locates in the housing 3 by means of a simple snap fit for easy replacement.
FIG. 4 shows the floor tool 1 without the removable portion. The opening 22 in the neck 5 of the tool is easily accessible by the user so that any blockages in the tool can be removed.
The invention permits the user easily to clean and maintain the floor tool himself, thereby saving the user the extra cost and the inconvenience of arranging for the tool to go into a repair shop. The removal of the brush bar arrangement through the suction opening greatly simplifies replacement of the brush bar.
Further variations will be apparent to the person skilled in the art. For example, other agitators in the form of brushes or beaters may be employed instead of the brush bar. The lever need not communicate with an end cap for locating the brush bar, as some other flange arrangement may be substituted. For example, the flange may locate a central region of the agitator in the housing. Furthermore, the lever may communicate directly with the agitator, so that a flange or end cap arrangement is not required. The agitator need not be rotatably mounted in the housing, but could instead be made, for example, to oscillate. The brush bar may be mounted in a cradle, which, in turn, is moveable with respect to the housing. The cradle permits the suction opening to float over the surface being treated. The removable portion of the housing may comprise this cradle. Furthermore, the tool need not include a turbine for driving the brush bar. | A tool for a surface treating appliance, such as a vacuum cleaner, includes a housing having a suction opening. An agitator, such as a brush bar, is rotatably located in the suction opening of the housing. The interior of such a tool can get blocked due to large objects being drawn in through the suction opening, or else by threads and fibers becoming tangled in the brush bar. The brush bar may be removed through the suction opening for replacement or repair. A portion of the housing may also be removable to clear the way for the user to access a narrow opening in the neck of the tool which may be prone to blockage. | 0 |
REFERENCE TO RELATED APPLICATION
This is a divisional application of U.S. patent application Ser. No. 08/064,437, filed on May 21, 1993 now U.S. Pat. No. 5,311,708.
FIELD OF THE INVENTION
The present invention relates generally to buildings and related structures, and more specifically to a system providing for the complete security and anchoring of all of the components of a completed family dwelling type structure or the like having a sloped roof, against high winds and related storm damage.
BACKGROUND OF THE INVENTION
In most areas of the nation, buildings and structures are subject to at least occasional high winds and severe storms. Hurricanes and tropical storms are relatively frequent occurrences with respect to the average life span of the typical building or dwelling, in the southeast and eastern parts of the country and occasionally hit the California coast and Hawaii as well. Tornados have been reported in every state in the union, including Alaska. Aside from such severe weather as mentioned above, severe thunderstorms can create localized gusts exceeding 100 miles per hour on occasion, and severe frontal systems can also cause extensive winds.
Accordingly, most areas of the country have developed building codes requiring minimum strength to provide at least some resistance to such severe conditions when they occur. While these requirements vary somewhat depending upon the specific area, they all are directed to new construction and do not address the need to anchor and secure a preexisting, completed structure. Of those devices and systems known, they primarily relate to means to anchor and retain temporary structures (e.g., mobile homes, sheds, haystacks and the like) and/or provide specialized components for use in the construction of new structures, which components are not readily adaptable for use in anchoring and securing portions of an already existing building.
The need arises for a system of anchoring and securing a preexisting, completed structure against high winds and storm conditions. The system must provide for the securing of shingles or like roof cover, securing the roof to the remaining structure, and securing the entire structure to the ground or foundation. Moreover, the system must be readily installable to the exterior of the structure without requiring any disassembly of the structure, and must be relatively inexpensive and easy to install.
DESCRIPTION OF THE PRIOR ART
U.S. Pat. No. 129,805 issued to Henry W. Forman on Jul. 23, 1872 discloses an Improvement In Portable Houses, comprising various specialized fittings for the assembly of the portable frame. These specialized fittings are used for the primary assembly of the structure, and thus the structure could not be assembled without them. The present invention comprises various fittings and the like which may be secured to a completed structure, which may stand alone without them.
U.S. Pat. No. 181,518 issued to Samuel M. Bollman on Aug. 29, 1876 discloses a Hay or Grain Cap comprising a multiple section, rigid pitched roof for temporary installation over a haystack or the like. Stakes tied to each corner may be driven into the ground to secure the device. No means of securing any shingles to the roof, securing the roof to an underlying building structure, or securing a building structure to its foundation is disclosed.
U.S. Pat. No. 194,455 issued to Robert Montgomery on Aug. 21, 1877 discloses Section-Roofs For Sheltering Grain, Etc. The device is similar to the Bollman patent discussed above, but depends primarily on weights suspended along the eaves for security. Additional security is provided by a stake driven into the hay or grain, and tied to the roof. A support structure for the roof is also disclosed, but no means of securing the roof to the support structure is shown.
U.S. Pat. No. 797,474 issued to James A. Walker on Aug. 15, 1905 discloses a Portable House utilizing specialized fittings to secure the structural members together temporarily. The fittings are integral with the balance of the structure, and cannot be removed while still leaving the structure standing. In other words, they cannot be applied to an existing, completed structure, as is the field of the present invention.
U.S. Pat. No. 822,143 issued to Alexander Mann on May 29, 1906 discloses a Stack Cover formed of a plurality of interlocked corrugated metal sheets, secured by a plurality of weights suspended from the eaves. No other securing means is disclosed.
U.S. Pat. No. 960,207 issued to Dwight C. Slater on May 31, 1910 discloses a Portable House along the lines of the Forman and Walker temporary structures discussed above. Again, the connecting members are integral with the remaining structure, and cannot be removed while still allowing the structure to stand, as in the case of the present invention.
U.S. Pat. No. 1,007,871 issued to James D. Horton on Nov. 7, 1911 discloses a Portable House along the lines of the Forman, Walker, and Slater patents discussed above. All of the structural connecting elements must be assembled with the structure, and cannot be added after the completion of the structure, as in the case of the present invention.
U.S. Pat. No. 1,864,403 issued to Charles B. Bradley on Jun. 21, 1932 discloses a House Anchor comprising two oppositely spaced cables extending over the roof and through sleeves installed through the roof at each corner of the house. No intermediate tiedowns are shown, nor is any means disclosed for securing shingles on the roof. Moreover, no structural ties between the roof structure and the wall structure are provided.
U.S. Pat. No. 1,932,555 issued to Philip L. McKee on Oct. 31, 1933 discloses a Greenhouse Eave (sic) Support And Drain Member comprising a vertical post having a specialized fitting thereatop to which the rafters and eaves are secured. The glass sidewalls extend between the eaves and foundation, and the glass roof is supported by the rafters. Thus, the structure is permanent, and the fittings must be assembled before the completion of the structure, as in the cases of the Forman, Walker, Slater, and Horton patents discussed above.
U.S. Pat. No. 2,372,827 issued to William A. Halicki et al. on Apr. 3, 1945 discloses a Roof Structure for permanent or semi-permanent structures, in which the connecting member is permanently secured between the eaves and the proximate sidewall during construction. As the member is captured beneath a part of the eaves structure as the building is assembled, it cannot be later installed after completion of the building, as in the case of the present invention.
U.S. Pat. No. 3,293,808 issued to Joseph R. Duncan on Dec. 27, 1966 discloses a Prefabricated Cornice For Roof Construction essentially comprising a soffit support to which a soffit and other trim can be secured. The soffit support is secured to the overlying rafter end and provides no more security to attach the roof to the underlying top plates, than the conventional technique of nailing the roof structure to the underlying top plates. The soffit support and accompanying structure must be assembled to the structure at the time of construction, as in the case of many of the devices described above.
U.S. Pat. No. 3,309,822 issued to William H. Dunkin on Mar. 21, 1967 discloses an Exterior Anchoring Apparatus For Surface Sheet. The apparatus comprises a series of cables and fasteners extending from the ridge of a gabled roof downward to each of the eaves, rather than laterally across one gable panel as in the present invention. No means is disclosed for securing shingles on a shingled roof, nor is any means disclosed for securing the roof structure to the remainder of the building.
U.S. Pat. No. 3,335,531 issued to Nardie F. Grimelli et al. on Aug. 15, 1967 discloses a Tie-Down For House Trailers Or The Like. The apparatus comprises a series of specialized brackets providing for the securing of a rope(s) or cable(s) across the flat roof of a mobile structure, and ground anchoring means. No similarity is seen to the present invention, as the apparatus is not readily adaptable to a fixed, permanently constructed and located structure having a sloped roof.
U.S. Pat. No. 3,415,019 issued to Melvin A. Andersen on Dec. 10, 1968 discloses an Integral Soffit And Fascia Unit Of Synthetic Plastic. The title is descriptive of the limitations in comparison to the present invention, in that the device is integral with the construction (one edge of the soffit is secured under the lower row of shingles) and formed of a non-structural material.
U.S. Pat. No. 3,449,874 issued to Jean L. Beaupre on Jun. 17, 1969 discloses a House Anchorage comprising a plurality of brackets secured to a house with cables tying the brackets to ground anchoring points. While some of the brackets are secured to the underside of the rafters at the eaves, the outward extension of the cables therefrom would result in significant obstruction of the walls of the house when working near such walls was required. Moreover, no shingle securing means or means of securing the upper wall structure to the roof structure is disclosed.
U.S. Pat. No. 3,949,527 issued to Paul B. Double et al. on Apr. 13, 1976 discloses a Material Supported Cover And Method For Securing Said Cover To The Ground. The patent is primarily directed to a specialized anchor plate which is installable in the ground. In the embodiment directed to securing a structure to the ground, no means of securing shingles or one portion of the structure to another of a permanently installed structure is disclosed; the only structure disclosed is a mobile home.
U.S. Pat. No. 4,257,570 issued to Carl M. Rasmussen on Mar. 24, 1981 discloses a Tie Down Assembly for use in securing a camper shell to a pickup truck or the like. No means of securing building structural components together or to ground anchors is disclosed.
U.S. Pat. No. 4,288,951 issued to Denny L. Carlson et al. on Sep. 15, 1981 discloses an Auxiliary Insulated Roof System for mobile homes, in which a bracket providing for the securing of the insulation to the upper wall structure is disclosed. No shingle securing means, means for securing rafters to the wall structure, or securing any of the structure to the ground or foundation is disclosed.
U.S. Pat. No. 4,365,453 issued to Colin F. Lowe on Dec. 28, 1982 discloses a Frameless Metal Building And Building Components comprising various sheet metal panels and attachment fittings. While the resulting building is permanent or at least semi-permanent, the fittings must be installed at the time of construction and serve as the primary securing means for the structure; they cannot be installed or removed after construction, as in the case of the present invention.
U.S. Pat. No. 4,587,789 issued to Garry Tomason on May 13, 1986 discloses an Anchoring Means For A Prefabricated Roof Or Siding Panel. The patent is directed to a means of securing specially formed, prefabricated roof or exterior panels from within, and does not lend itself to securing previously completed structures using standard construction methods and materials from the exterior after completion. Moreover, no means of securing the structure to a foundation or to the ground is disclosed.
U.S. Pat. No. 4,697,393 issued to Herbert R. Madray on Oct. 6, 1987 discloses a Metal Building Construction along the lines of the fittings of the Forman, Walker, Slater, and Horton patents discussed above. The fittings must be installed during construction, and are inherent in the strength of the completed structure. They cannot be ether installed or removed after construction, as in the case of the present invention.
U.S. Pat. No. 4,796,403 issued to David A. Fulton et al. on Jan. 10, 1989 discloses an Articulating Roofing Panel Clip for securing standing seam sheet panels together. The clip(s) cannot be installed over an existing, completed roof structure and do not lend themselves to installation on shingled roofs or to secure any other structural components to one another or to the ground.
Finally, U.S. Pat. No. 5,109,641 issued to Peter Halan on May 5, 1992 discloses Roof Transition Flashing for installation at the juncture of a sloped roof and vertical siding. The flashing fails to anchor any of the structure to any other part of the structure, and must be installed during construction.
None of the above noted patents, taken either singly or in combination, are seen to disclose the specific arrangement of concepts disclosed by the present invention.
SUMMARY OF THE INVENTION
By the present invention, an improved anchor system for completed structures is disclosed.
Accordingly, one of the objects of the present invention is to provide an improved anchor system which is adaptable to secure or anchor the components of a completed building structure to the earth or foundation of the structure.
Another of the objects of the present invention is to provide an improved anchor system which is particularly adaptable to residential structures having sloped roofs, e.g., single family residences, townhouses, and associated structures, such as garages and sheds.
Yet another of the objects of the present invention is to provide an improved anchor system which provides external means for securing the shingles of a shingled roof against wind damage.
Still another of the objects of the present invention is to provide an improved anchor system which provides means for externally securing the roof structure of a building to the upper wall structure of the building.
A further object of the present invention is to provide an improved anchor system which also provides external means for securing the roof structure of a building directly to the ground or to the foundation of the structure, thus also securing the walls between the roof and the around or foundation.
An additional object of the present invention is to provide an improved anchor system which makes use of readily available materials and components.
Another object of the present invention is to provide an improved anchor system which utilizes threaded fasteners exclusively wherever fasteners are required.
A final object of the present invention is to provide an improved anchor system for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purpose.
With these and other objects in view which will more readily appear as the nature of the invention is better understood, the invention consists in the novel combination and arrangement of parts hereinafter more fully described, illustrated and claimed with reference being made to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a broken away perspective view of a sloped, shingled roof, showing the details of the shingle anchoring system of the present invention.
FIG. 2 is an elevation view in section of the upper wall and roof truss area of a structure, showing details of the wall to roof securing means of the present invention.
FIG. 3 is a perspective view of one side of a building structure, showing the means used to secure the roof structure directly to the foundation and/or around.
Similar reference characters denote corresponding features consistently throughout the several figures of the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, the present invention will be seen to relate to a system providing for the securing of various components of a building structure together, and for the securing of a building structure to an underlying foundation or to the around.
FIG. 1 of the drawings discloses a means of securing shingles on a sloped, shingled roof according to the present invention. It is well known that shingles are very susceptible to damage from storms with high winds, if the wind lifts the shingles and tears them away from the underlying roof sheathing. The problem lies in the securing of the lower edge of each of the rows of shingles on such a roof, as the upper edge of each row is secured beneath the adjacent overlying row up to the roof ridge. Accordingly, the present invention provides a means to secure the lower edge of each row of shingles by means of a plurality of transverse shingle securing lines or cables 10 which are installed laterally across the shingles S. Lines 10 are preferably installed a distance D approximately 1-1/2 inches up slope from the lower edge E of each row A of the shingles S, in order to preclude the lifting of any of the lower edges E of the shingles S. Lines 10 are secured at each end rafter ER (one of which is shown in FIG. 1; the opposite end of the roof of FIG. 1 will be seen to be essentially a mirror image of the end shown) by an eye bolt 12. Eye bolts 12 are provided with threaded lag screw ends and screwed through the shingles S, roof sheathing thereunder, and into the end rafter ER, with each end of each line 10 drawn taut across a respective row A of shingles S and secured around a respective eye bolt 12 by a braided eye 14. Preferably, each line 10 is formed of a braided polyester material having an open core in its relaxed condition, thereby providing for ease of formation of the braided eyes 14 at each end. The braided polyester material has been found to be relatively durable and resistant to sunlight and other potential causes of deterioration, and at the same time relatively economical. Other materials may be used if desired, such as stainless steel cable, and preferably stainless steel anchors such as eye bolts 14 are used in order to provide corrosion resistance and long life.
Each of the lines 10 is further secured to each of the other intermediate rafters R between the two end rafters ER, by a plurality of overlying straps 16 which tie each line 10 down at each rafter R. Each strap or clamp 16 is secured on either side of its respective line 10 preferably by a stainless steel spiral threaded roofing nail 18, with a third like nail 18 driven through the center of the strap 16 and through the line 10 thereunder to provide additional security. Straps or clamps 16 are preferably copper for corrosion resistance; however, other materials (e.g., stainless steel) may be used as desired. Thus, every shingle S on the roof is secured, as each row A of shingles S will have an overlying line 10 extending transversely thereacross approximately 1-1/2 inches up from the lower edge E. The lower edges E of the shingles are therefore prevented from lifting due to high winds or other causes, and yet the placement of the lines 10 a short distance D upward from the lower edges E of each row A of shingles S, serves to prevent the shingles S from curling back under the lines 10 to lift above the lines 10. The above discussed element of the structural security system of the present invention will be seen to be applicable to a completed structure, with no dismantling of any of the structure required for its installation on the structure. Moreover, one of the key elements of the present invention will be seen to be its use of threaded fasteners to secure each element or component; the use of standard, non threaded nails or the like is avoided. The threaded fasteners used throughout the system of the present invention provide a substantial increase in security between components thus secured.
While the above element of the system serves to prevent shingle damage or loss in high wind or storm conditions, and thereby prevent water damage to the interior of the structure and its contents, it does nothing to secure major structural components together to prevent major structural damage or destruction of the structure. One of the major causes of structural damage in extremely high wind conditions (hurricanes, severe thunderstorms and tornados, etc.) is the lifting and removal of the entire roof from the remainder of the structure. Considering that conventional frame structures rely primarily upon the weight of the roof to keep the roof in place, with the structure being secured only by a relatively few standard nails, it is not surprising that high winds can often remove a roof from a structure.
FIG. 2 of the drawings discloses a means for securing the roof of a structure to the adjacent upper walls. FIG. 2 discloses a section of a conventional framed structure, having substantially vertical wall studs W topped by a top plate P, with a ceiling joist J immediately adjacent and thereabove. A sloped rafter R is installed atop the joist J, in the conventional manner as shown in FIG. 1. However, rather than merely allowing the joist J and remaining roof structure to rest upon the upper plate P, an additional tie 20 is installed at the juncture of each of the wall studs W and ceiling joists J. These wall stud to ceiling joist ties 20 are installed externally to a previously completed structure, as in the case of the shingle securing system discussed above. Each tie 20 is preferably formed of a strap of stainless steel some 1-1/2 inches wide, or equal in width to the standard 1-1/2 inch thick "two by fours" generally used for wall stud construction. A right angle bend is formed in the strap or tie 20, enabling the tie 20 to be secured to both the upper portion of the wall stud W and also to the ceiling joist J and rafter R thereabove. By providing a strap or tie of some eight inches in length, the majority (preferably some five inches) may be secured to the vertical wall stud W, with the remaining length secured to the adjacent joist J, or through the adjacent joist J and into the rafter R thereabove. Threaded screws or bolts of sufficient length to penetrate substantially the majority of the depth of the secured members are provided, such as the lag bolts 22 shown in FIG. 2. Bolts 22 are again preferably formed of stainless steel for corrosion resistance and long life; however, other materials may be used if so desired. It will be noted that the lag bolts 22 penetrating the wall studs W are somewhat shorter than the lag bolts 22 penetrating the ceiling joist J and rafter R, due to the greater depth of material provided by the ceiling joist J and rafter R. By providing bolts 22 of proper length, it will be seen that all three of the major structural elements shown in FIG. 2-- the wall stud W, the ceiling joist J, and the rafter R-- may be tied together with a single tie 20. This provision of a single tie 20 to secure together all of the above elements, provides for additional security for a structure so secured. Further security may be provided by securing an additional bolt (not shown) into the upper plate P, immediately beneath the ceiling joist J. While the thickness of the soffit immediately beneath the eaves may not allow sufficient depth along the exterior wall for such an additional bolt, in many cases a double upper or top plate is installed and the three inch thickness thereby provided, serves to provide sufficient depth for an additional lag bolt into the lower one of the double top plate members.
For even greater security, the tie 20 may be provided in a longer length, having an extension 20a which may be bent to an angle complementary to the slope of the rafter R and secured directly thereto with additional bolts 22. The bolts 22 secured directly into the end of the rafter R and through tie extension 20a, serve to provide additional security over the portion of tie 20 which is held by bolts 22 which are secured indirectly to the rafter R through the joist J. In any case, the provision of means to secure each of the above structural components together by means of threaded fasteners 22, provides for a major strengthening of the upper portion of the structure.
While the above two elements of the present invention serve to secure the shingles to the roof of a structure, and to secure the roof of the structure to the upper walls, even further security is required in some cases. The present invention further provides for the securing of the roof structure directly to the foundation F or to ground anchors 24, as shown in FIG. 3. FIG. 3 discloses a plurality of eye bolts 12 which are screwed into the rafters R from the bottom, preferably on the order of four inches outward from the exterior surface of the wall. In order to preclude blockage of doorways, windows or other areas as desired, no eye bolts 12 are provided in those rafters R directly in front of such areas.
A like plurality of anchor points is provided in the foundation F or in the ground adjacent the foundation F, as desired and as appropriate for the conditions. In FIG. 3, a plurality of ground anchors 24, comprising large masses of concrete or other suitable anchor means (e.g., buried steel anchors or columns), with tiedown eyes 26 extending therefrom, is shown to the right side of the drawing, while additional eye bolts 12 are secured into the foundation F by means of lag shields or other suitable anchor means. Preferably, the underlying structural anchor means provided by ground anchors 24 are installed no more than six inches outward from the perimeter of the structure, in order to keep all tiedown lines or cables 28 close to the structure and substantially parallel to the walls, thus avoiding entanglement with such lines 28 by a person working near the exterior walls of the structure (e.g., gardening, etc.) The precise distance out from the walls for the installation of the eye bolts 12 into the rafters R, and the placement of the ground anchors 24 and foundation eye bolts 12, may be adjusted in order to ensure that the tiedown lines or cables 28 are substantially parallel to the walls and relatively close to the structure when installed.
A plurality of tiedown lines or cables 28 equal to the number of eye bolts 12 installed in the rafters R along the eaves of the structure, is then installed, drawn taut in the manner of the shingle securing lines 10, and secured at opposite ends to a respective rafter eye bolt 12 and ground anchor tiedown eye 26 or foundation eye bolt 12, as appropriate, by means of a braided loop or eye 14, as shown in FIG. 1. Roof or rafter tiedown lines 28 are preferably formed of the same material as the lines or cables 10 used to secure the edges of the shingles S, as shown in FIG. 1. It will be seen that the securing of the rafters R directly to any underlying structure comprising the foundation F or ground anchors 24, results in tile remainder of the roof structure, the wall structure, and any other interposed structure, being captured between the roof rafters R and the foundation F or ground anchors 24. Moreover, while each individual tiedown line or cable 28 may not provide sufficient strength to secure a large structure in a high wind, the plurality of cables or lines 28 provided by the present invention will be seen to provide sufficient strength and security to secure an average frame structure under most conditions of wind and storm which might be anticipated in most areas.
Accordingly, it will be seen that the present invention provides for the complete securing of a one or two story frame structure having a sloped, shingled roof, to the ground or to its own foundation to preclude shingle or roof damage, removal of the roof from the rest of the structure, or displacement of the structure from the foundation due to severe storms and high winds. The present invention lends itself well to single family homes and similar or related structures which have already been completed and which have been permanently and immovably constructed on a building site. The use of only external anchor and tiedown means, as well as the exclusive use of threaded fasteners and anchors throughout the present invention, results in a system which is both simple to install and which is also extremely durable and secure.
It is to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims. | A system for securing a building structure, and various components of a building structure, to one another and/or to the building foundation or ground, is provided. The system includes apparatus for securing shingles against wind damage on a sloped, shingled roof; apparatus for securing the roof structure of a building to the adjacent upper wall structure; and apparatus for securing the roof structure directly to the foundation of the building or to the ground. The system is particularly adaptable to single and two story residential dwellings, such as single family homes and townhouses, and their related structures, such as garages and sheds, having sloped, shingled roofs. Installation of the complete system of the present invention provides substantial additional security for a structure against storm damage, particularly due to high winds. | 4 |
This is a continuation of application Ser. No. 08/071,091, filed Jun. 4, 1993 and now abandoned.
FIELD OF THE INVENTION
The field of the invention relates to communication systems.
BACKGROUND OF THE INVENTION
Time assigned speech interpolation (TASI) and digital speech interpolation (DSI) techniques are often used within public switched telephone networks (PSTNs) where speech signals must be exchanged between two or more points (switching centers) over a limited number of grouped physical channels (e.g., over T1 lines). Where high capacity T1 span lines are used the number of lines needed is determined by dividing an estimate of the total number of traffic channels needed at a switching center by the number (N) traffic channel provided per T1 line.
In some PSTNs each traffic channel of the N traffic channels per T1 line is allocated to a call for the duration of the call. While such a technique may produce reliable telephone service of good quality, such technique is wasteful. The technique is wasteful because normal speech is often punctuated by pauses between sentences or between words within a sentence. Such pauses causes the traffic channel to remain idle during the pause instead of transmitting voice information.
To reduce the waste associated with idle traffic channels, a TASI or DSI (TASI/DSI) system limits allocation of traffic channels to periods between pauses (where information is available for transmission). Where a pause occurs during speech, the channel is released for use by another user. When speech resumes the next available channel is allocated in support of the conversation.
Key to the successful operation of a TASI/DSI system is determination, during set-up of the system, of an accurate estimate of an average voice activity factor (VAF) of a set of grouped physical channels. A VAF is an estimate of the ratio of speech time to the sum of speech plus pauses. VAFs are typically estimated by system designers because of the difficulty of measuring individual voice channels and of obtaining an average of a channel group.
The VAF is used by the TASI/DSI system as a measure of the additional users that may be granted access over the number of physical channels available (e.g., if the VAF=50% then 2 users may be granted access for each physical channel present). Where a VAF is estimated high, communication resources are again wasted because traffic channels again remain idle. Where the VAF is estimated low, voice information may be lost because too many users may be allowed access to the communication system. Where too many users are allowed access to the system, a traffic channel may not be available following a pause, resulting in speech loss (clipping). The speech clipped, in such a case, is that fraction (cutout fraction) of the speech presented to the system before a traffic channel becomes available.
Speech has been determined by Weinstein (Fractional Speech Loss and Talker Activity Model for TASI and for Packet-Switched Speech, C. J. Weinstein, IEEE Transactions, August 1978) to be acceptable if the cutout fraction does not exceed 0.5%. The cutout fraction, in accordance with Weinstein, can be determined by solving the equation: ##EQU1## where φ is the cutout fraction, n is the number of users, c is the number of traffic channels, and p is the estimated VAF.
While TASI/DSI systems often work well, the success of such systems depends on the accurate estimate of the VAF. Where the VAF is incorrectly estimated, or the VAF changes, then the system must be modified to correct for inefficient use or poor speech quality. In addition, where the character of the information on the traffic channels changes during certain periods of the day (e.g., an increase in facsimile messages during the afternoon) the quality of performance of the TASI/DSI system may suffer. Because of the importance of reliable communication a need exists for a method of applying TASI/DSI to cellular communication systems and of adapting TASI/DSI operating characteristics to the changing information content of the traffic channel.
SUMMARY OF THE INVENTION
In a resource limited communication system having at least one physical channel shared by a plurality of time divided users, a method is provided of dynamically adjusting a maximum number of users allowed access to the at least one physical channel. The method includes the steps of calculating a voice activity factor for each user of the plurality of time divided users and adjusting the maximum number of users based upon the calculated voice activity factors. An apparatus is provided for implementing the described method.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a cellular base site in accordance with one embodiment of the invention.
FIG. 2 is a flow chart illustrating a method for determining a maximum number of users in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The solution to the problem of clipping and inefficiency within a resource limited TASI/DSI cellular communication system under a varying VAF lies in determining an average VAF for users within the system over a time interval based upon vocoder activity at a cellular base site and adjusting a maximum number of users based upon the determined average VAF. Such adjustment allows for maximum voice quality and efficiency by dynamically adjusting the maximum number of users within the system to the VAF of the users of the system.
FIG. 1 is a block diagram of a base site, generally, 10 in accordance with one embodiment of the invention. Included within the base site 10 is a number of vocoders 15-16 and a lesser number of transceivers 12-14 capable of being interconnected with vocoders 15-16 through a switch 17. Transceivers 12-14 provide a primary means for interfacing with subscribers units 21-22 over an air interface 20. The vocoders 15-16 may be any digital signal processor (DSP) (e.g., a DSP68000 available from Motorola, Inc.) capable of voice coding and of determining a VAF based upon the number of frames of voice information coded per time period.
Upon receipt of an access request from a subscriber 21 by a transceiver 12-14 the request is forwarded to a base site controller 11 for validation of an ID of the subscriber 21 contained within the access request and a determination of channel availability. Also contained within the access request is an ID number of a communication target located within a service coverage area of the same or another base site 10 or within the public switched telephone network (PSTN)
Upon validation of the ID of the subscriber 21 and determination of channel availability, the controller 11 may transmit a call request through a PSTN interconnect (for a PSTN target) requesting access to the target. The controller 11 causes an access grant to be transmitted to the subscriber 21 through a transceiver (e.g., 12) identifying an allocated channel for use during the communication transaction. The controller 11 also allocates a vocoder (e.g., 15) and a signal path within the switch 17 between transceiver 12 and vocoder 15. Upon receipt of the access grant by the subscriber 21, the subscriber 21 and transceiver 12 tune to the allocated channel and the communication transaction between subscriber 21 and target (within the PSTN) may begin on the trunked physical channel comprising the allocated radio channel 20, transceiver 12, switch 17, and vocoder 15.
Under one embodiment of the invention, allocation of resources within the base site 10 is limited to periods when information is available for exchange between the subscriber 21 and target. Limitation of the allocation of resources to periods when information is available for exchange allows a portion (or all) of a trunked physical channel to be re-assigned to other users. During speech pauses some communication resources (e.g., transceivers) of the physical channel may be used by other time divided users of that part of the physical channel while other parts of the physical channel remain dedicated to the prior user.
Key to the successful re-allocation of communication resources at the base site 10 is a determination of a VAF of each user and the use of the VAF in setting a maximum number of users of communication resources within the base site 10. Where an average VAF of users within a system is low and the number of users large, the statistical probability of clipping as a result of additional users, in excess of the number of physical channels available, is low.
As a means of describing the invention, operation of a base site 10 constructed with a lesser number of transceivers 12-14 than vocoders 15-16 will be described with further reference to FIG. 2. During pauses, transceivers 13-14 are released to other users. Other communication resources (e.g., vocoders 15-16) remain dedicated to a particular user. The reader is reminded, on the other hand, that the invention may be extended to any communication resource or combination of communication resources (e.g., vocoders, radio channels, etc.) available through the base site 10.
In the above described communication transaction, following call set-up, the controller constantly determines a VAF for each subscriber 21 granted access through the base site 10. The VAF may be determined by setting a counter within the vocoder to record the number of frames of information per time period coded for a particular user (Step 105).
An average VAF is then determined for all users of the base site 10 for use in setting a maximum number of users allowed access through the base site 10 (Step 110). The maximum number of users at the base site is then determined by evaluating the cutout fraction for a various number of users (n), and determining the largest n that has and acceptable cutout fraction (Step 115).
In one embodiment of the invention the maximum number of users is determined based on the Weinstein equation (above). For the case where a base station has 30 voice circuits and an average VAF of 0.50, a maximum number of allowable users, while still maintaining a clipping level of less than 0.5%, is 50 users.
Upon determination of a maximum number of users, the controller 11 continues to grant communication access up to the maximum calculated. When the number of users reaches the maximum calculated number the controller 11 refuses new requests. Where the maximum number of users decreases because of a change in average VAF then the controller either drops calls or reduces the number of users by attrition (Step 120).
Setting a maximum number of users within a cellular communication system by calculating an average VAF allows for maximum utilization of cellular equipment while optimizing voice quality. Such a procedure allows for a changing composition of users within the cellular system without compromising efficiency or performance.
In another embodiment of the invention a base site 10 is constructed with an equal number of vocoders and transceivers. Under such an embodiment, both vocoders, transceivers, and radio channels are released to other users. When speech is to begin from a subscriber 21, the subscriber unit transmits an access request on a control channel identifying the appropriate on-going communication transaction. The controller 11 upon receipt of the request allocates a transceiver, vocoder, and radio channel in support of the transmission. Upon completion of the transmission the resources are again released. Upon receipt of information from a PSTN subscriber the controller 11 causes a transceiver to transmit notification to the subscriber 21, notifying the subscriber of the need to tune to a newly allocated channel for receipt of the information.
As above a VAF is calculated for each user operating through the base site 10. A maximum number of users is determined based upon the number of resources and the VAF, using the Weinstein equation.
The many features and advantages of this invention are apparent from the detailed specification and thus it is intended by the appended claims to cover all such features and advantages of the system which fall within the true spirit and scope of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art (such as application of the invention to T1 lines), it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
It is, of course, to be understood that the present invention is, by no means, limited to the specific showing in the drawing, but also comprises any modification within the scope of the appended claims. | In a resource limited communication system having at least one physical channel shared by a plurality of time divided users, a method is provided of dynamically adjusting a maximum number of users allowed access to the at least one physical channel. The method includes the steps of calculating a voice activity factor for each user of the plurality of time divided users and adjusting the maximum number of users based upon the calculated voice activity factors. An apparatus is provided for implementing the described method. | 7 |
RELATED APPLICATIONS
There are no current co-pending applications.
FIELD OF THE INVENTION
The presently disclosed subject matter is directed toward security devices. More particularly, the present invention relates to security devices for preventing personal items such as purses, clothing, luggage, or the like from being stolen or moved while sitting unattended.
BACKGROUND OF THE INVENTION
Very few leisure time activities rival that of spending warm summer days at the beach. Some enjoy being around a pool with all the comforts of home, while others spend time outside tanning. Whatever the reason, all of these events share common items such as beach towels, beach bags, clothing, or the like. However, when a person wishes to go into the water or otherwise walk away for a few short moments, one runs the risk of having their personal items stolen.
Even if they are not stolen, they can be picked up by someone else and moved to another location where they cannot be easily found. Similar difficulties appear when traveling and personal items such as coats, jackets, luggage, or the like must be left alone for short periods of time.
Accordingly, there exists a need for a means by which easily movable or stolen items can be easily secured against theft or unauthorized movement.
SUMMARY OF THE INVENTION
The principles of the present invention provide for a securable locking clip that can grasp items such as towels, clothing, purses, luggage, or the like in its clasping jaws/or by using a flexible secure cable. The securable locking clip can then be attached to a stationary object to prevent a person from taking or moving the items.
The securable clip is a lock suitable for preventing the theft, loss, or misplacing of beach towels, luggage, purses, or other personal items. One (1) end of the securable clip is hinged and receives a flexible wire cable, while the opposite end has interlocking jaws that can grip a towel or similar item. The securable clip has a movable hasp which squeezes the jaws together and prevents their opening. The hasp is held in place by a conventional padlock which can be secured to a stationary object such as a beach chair, post, table, or similar item using the flexible wire cable. In addition, various items such as purses, luggage, briefcases and the like can be secured in place by passing the flexible steel cable through the handle of the item and then securing it to a stationary object. Additionally, the securable clip can have a label for providing information such as owner's name, room number, and telephone number.
A securable clip in accord with the present invention includes a “C”-shaped clip having a hinge at one (1) end, an upper jaw extending from the hinge and a lower jaw extending the hinge. The upper and lower jaws are biased open by the hinge and they both include a tapered section located adjacent the hinge. The upper jaw and lower jaws also include clamping teeth. Force applied to the tapered section can force the upper jaw and lower jaw closed. The upper jaw also includes latching teeth on an outer surface. The securable clip also includes an adjustable band that is dimensioned to fit over the hinge and to apply a force that closes the jaws when the adjustable band is moved along the tapered section. The adjustable band including an integral hasp having an actuator tab and a locking tip. When the locking tip engages a latching tooth it secures the upper jaw and lower jaw closed.
Beneficially the clip is a molded plastic structure, the adjustable band is hollow and forms a rectangular inner opening, and the upper jaw and lower jaw include aligned padlock apertures. Also beneficially the actuator tab can pivot the locking tip out of contact with the latching tooth. A padlock for passing through the aligned apertures may also be included. A cable may also be included, preferably plastic coated and having an eyelet. An identification label may be attached, preferably on the upper jaw.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
FIG. 1 is an environmental view of a securable clip assembly 10 that is in accord with a preferred embodiment of the present invention when in-use;
FIG. 2 is another environmental view of the securable clip assembly 10 shown in FIG. 1 when secured to a structure 110 ;
FIG. 3 is a close-up view of an assembled securable clip assembly 10 as shown in FIGS. 1 and 2 ;
FIG. 4 is a section view of the securable clip assembly 10 taken along section line A-A of FIG. 3 ; and,
FIG. 5 is an exploded view of the securable clip assembly 10 shown in FIGS. 1 through 4 .
DESCRIPTIVE KEY
10 securable clip assembly
20 clip
22 hinging end portion
24 upper jaw
26 lower jaw
28 clamping tooth
30 padlock aperture
32 latching tooth
34 identification label
50 adjustable band
52 band
54 band aperture
60 clasp
62 actuator tab
64 locking tip
80 cable
82 eyelet fixture
86 padlock
87 padlock clasp
100 towel
102 personal item
110 structure
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within FIGS. 1 through 5 . However, the invention is not limited to the described embodiment, and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one (1) of the referenced items.
Referring principle to FIG. 1 , the preferred embodiment of the present invention is a securable clip assembly 10 that helps prevent theft of fabric-based items such as, but not limited to, beach towels 100 , blankets, clothing items. The securable clip assembly 10 is also useful for securing personal items 102 such as purses, luggage, and the like to a stationary structure. The securable clip assembly 10 is especially useful in a vacation/beach environment.
Refer now to FIGS. 1 and 2 , environmental views of the securable clip assembly 10 when in-use, and to FIG. 3 , a close-up view of the securable clip assembly 10 . The securable clip assembly 10 includes a clamping clip 20 , an adjustable band 50 , and a length of cable 80 which is secured to the clip 20 using a conventional padlock 86 . The securable clip assembly 10 provides mechanical clamping forces to secure various items such as towels 100 , robes, jackets, purses, suitcases, and the like to a stationary structure 110 . This reduces the possibility of tampering, theft, or misplacement which increases the peace of mind of a user.
Refer now to FIGS. 3 , 4 , and 5 , close-up, sectional, and exploded views of the securable clip assembly 10 . The securable clip assembly 10 uses a generally “C”-shaped clip 20 which is approximately two-and-one-half inches (2½ in.) long and approximately one-and-one-half (1½ in.) inches wide. However, it should be understood that the actual dimensions of the securable clip assembly 10 may vary based upon a user's preference and particular applications. The clip 20 is beneficially a one-piece molded plastic structure that is envisioned as being made using an injection-molding process and as being available in a variety of colors and patterns.
The clip 20 has a molded hinge 22 at one end and a set of tapered jaws at the other. The tapered jaws includes a forward extending upper jaw 24 and a forward extending lower jaw 26 that are biased open by the hinge 22 . The clip 20 is configured to have a downward tapered cross-section around the hinge 22 . The upper jaw 24 and lower jaw 26 also include a plurality of clamping teeth 28 that interlock when the jaws 24 , 26 are forced closed as described below. When not forced closed the upper jaw 24 and the lower jaw 26 are biased open about one inch (1 in.) by the hinge 22 . This allows a user to slide a towel 100 or similar item between the open jaws 24 , 26 .
After the towel 100 or other item is placed between the upper jaw 24 and the lower jaw 26 those jaws 24 , 26 are forced closed by sliding the adjustable band 50 forward along the tapered surfaces of the clip 20 near the hinge 22 . To that end the adjustable band 50 has a hollow rectangular band section 52 that forms a rectangular inner opening that encompasses the tapered surfaces of the clip 20 near the hinge 22 . As the adjustable band 50 slides forward along the clip 20 the jaws 24 , 26 are forced together, thus clamping the towel 100 . The adjustable band 50 is retained in a clamping position by an integral hasp 60 having a user accessible actuator tab 62 at one (1) end and a locking tip 64 at the other. The locking tip 64 engages one (1) of a plurality of latching teeth 32 that are molded into the upper jaw 24 . Engagement of the locking tip 64 into one of the latching teeth 32 secures the hasp 60 in position, which secures the closing of the jaws 24 , 26 .
The jaws 24 , 26 can be easily opened by a user depressing the actuator tab 62 . This pivots the locking tip 64 out of contact with the latching teeth 32 . The hasp 60 can then be rocked back and forth to slide it down the clip 20 taper. This enables the bias force of the hinge 22 to open the jaws 24 , 26 , releasing the item(s) placed between them.
Once the towel 100 or other item is secured within the clip 20 that clip 20 can be secured to a structure 110 (see FIG. 2 ) using the conventional padlock 86 . To that end the clip 20 includes a pair of padlock apertures 30 that are formed through the jaws 24 , 26 behind where the adjustable band 50 locks the jaws 24 , 26 closed. The padlock apertures 30 are aligned and allow the padlock 86 clasp to pass through. The cable 80 , preferably one (1) with a plastic-coating, has a pair of eyelets 82 . The cable 80 is wrapped around or otherwise secured to the structure 110 , the eyelets 82 are secured by the padlock clasp 87 , the padlock clasp 87 is passed though the padlock apertures 30 , and then the padlock 86 is locked.
Additionally, the clip 20 includes an identification label 34 that is affixed to a top surface of the clip 20 . This enables convenient display of information such as owner's name, room number, telephone number, or the like to be applied.
It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and while only one particular configuration is shown and described that is for purposes of clarity and disclosure and not by way of limitation of scope.
The preferred embodiment of the present invention can be used by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the securable clip assembly 10 it would be installed as indicated in FIGS. 1 and 2 .
The method of using the securable clip assembly 10 may be achieved by performing the following steps: procuring the securable clip assembly 10 ; removing the padlock 86 and adjustable band 50 , if previously installed; inserting a towel 100 or similar item between the upper 24 and lower 26 jaws; sliding the adjustable band 52 over the hinge 22 ; sliding the adjustable band 52 along the tapered surfaces of the clip 20 to force the jaws 24 , 26 ; securing the adjustable band 50 in position by allowing the locking tip 64 of the clasp 60 to engage a corresponding latching tooth 32 of the upper jaw 24 ; using the identification label 34 to note information such as an owner's name, room number, telephone number, or the like; wrapping or otherwise securing the cable 80 to a structure 110 , securing the cable 80 to the padlock using the eyelets 82 ; locking the padlock 86 ; and then benefiting from the secure attachment of one's towel 100 or other personal property 102 to the stationary structure 110 .
The cable 80 may be routed through and around suitable personal items 102 and through a stationary structure 110 such as a beach chair, and the padlock claps 87 inserted through the eyelets 82 of the cable 80 , and through the padlock apertures 30 of the clip 20 , thereby providing a means to securely anchor the securable clip assembly 10 and personal items 102 .
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. | A security device to prevent the theft of personal items comprises a plastic clip with an adjustable movable hasp on a first end and interlocking gripping teeth on an opposing second end. The movable hasp squeezes the jaws together and prevents their opening. The hasp is in turn held in place by a padlock which can secure the device to a stationary object such as a beach chair, post, table, or similar item using a flexible cable. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application Nos. 60/866,081 filed Nov. 16, 2006 and 60/806,633 filed Jul. 6, 2006.
BACKGROUND OF THE INVENTION
[0002] This invention is directed toward a rechargeable hearing device and charging receptacle. Rechargeable hearing devices are known in the art. These devices are not aesthetically appealing nor are they easy to use and recharge. Thus, there is a need for a hearing device and charger that address these deficiencies.
[0003] Thus, a principal object of the present invention is to provide an improved method of recharging a hearing device that facilitates use.
[0004] These and other objects, features, or advantages of the present invention will become apparent from the specification and claims.
BRIEF SUMMARY OF THE INVENTION
[0005] An improved method for recharging a hearing device. The steps include providing a hearing device that has a main body with an earphone thereon and a first charging element. The next step involves providing a charging device that has a receptacle therein that has a second charging element. The method is completed by inserting the hearing device into the receptacle of the charging device such that the first and second charging elements interact with one another to recharge the hearing device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a perspective view of a hearing device within a charging device;
[0007] FIG. 2 is a perspective view of a charging device;
[0008] FIG. 3 is a perspective view of a charging device;
[0009] FIG. 4 is a front plan view of a hearing device;
[0010] FIG. 5 is a side plan view of a hearing device;
[0011] FIG. 6 is a back plan view of a hearing device; and
[0012] FIG. 7 is an elevation view of a hearing device in combination with a charging device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] The hearing device 10 has a main body 12 having a front and back panels 14 and 16 . Preferably, the main body 12 has a tear-drop shape. Mounted on the front panel 14 is an on/off switch 18 , a power indicator LED 20 , and an MIC 22 (microphone). The power indicator LED 20 has a plurality of colors to indicate different operating states. For example, green could mean normal, red could mean low power, and yellow could mean charging.
[0014] Mounted on the back panel 16 is an earphone 24 and a hook holder 26 . The earphone 24 is formed to receive an ear cushion and is positioned to fit within the ear canal. The hook holder 26 is formed to receive a hook 28 that fits over the ear.
[0015] Mounted at one end of the main body 12 and between the front and the back panel is a rotatable volume dial 30 . Mounted to the sides of the main body 12 are a pair of charge plates and/or ports 32 .
[0016] The hearing device 10 is formed to be matingly received within a charging device 34 . The charging device 34 has a receptacle 36 formed therein with a pair of charge plates and/or prongs 38 that align with the charge plates 32 on the hearing device when the hearing device is inserted within the charging receptacle 36 . Mounted on the exterior of the charging device 34 is an indicator LED 40 that indicates the operational state of that charging device 34 . For example, when the indicator LED 40 is yellow, this would indicate a charging state and when the indicator LED 40 is green this would indicate the power is on.
[0017] The charging device 34 has a storage chamber 42 that is enclosed by a door 44 that is hingedly connected to the charging device 34 . A release button 46 is mounted on the charging device 34 such that when engaged the door 44 is released allowing access to the storage chamber 42 . The storage chamber 42 is for holding hearing device equipment such as ear cushions, a cleaning broom, and the like. In one embodiment the door 44 has sub-chambers 48 formed to receive the hearing device equipment. The charging device 34 has a power cord 50 that connects with a power supply.
[0018] In an alternative embodiment the earphone 24 is detachable from the main body 12 of the hearing device 10 . Specifically, the earphone 24 comprises a positive battery contact plate 52 at its base that contacts a similar negative battery contact plate 54 within the main body 12 of the hearing device 10 when the two separate pieces are attached together. Upon contact of the positive and negative battery contact plates 52 and 54 the earphone 24 can be recharged. Thus, an individual using the hearing device has the choice of placing the entire hearing device 10 including the main body 10 with the hook 28 and earphone 24 attached therein into their ear or they may remove the earphone piece from the main body 12 and place only the earphone 24 within their ear. In this embodiment the charging device is designed to accommodate the two-piece hearing device.
[0019] It will be appreciated by those skilled in the art that other various modifications could be made to the device without the parting from the spirit in scope of this invention. All such modifications and changes fall within the scope of the claims and are intended to be covered thereby. | A method and apparatus for recharging a hearing device. The method includes providing a hearing device and a charging device wherein each has a charging element. The method then involves inserting the hearing device into the charging device such that the first and second charging elements interact to recharge the hearing device. | 7 |
TECHNICAL FIELD
The present disclosure relates generally to a metrology model, and more particularly, to a method and system for implementing virtual metrology in semiconductor fabrication.
BACKGROUND
Semiconductor integrated circuits are produced by a plurality of processes in a wafer fabrication facility (fab). These processes, and associated fabrication tools, may include thermal oxidation, diffusion, ion implantation, RTP (rapid thermal processing), CVD (chemical vapor deposition), PVD (physical vapor deposition), epitaxy, etch, and photolithography. During the fabrication stages, semiconductor wafers are monitored for quality assurance and yield using various metrology tools.
Virtual metrology is a technique that forecasts results of a semiconductor process based on modeling and previously collected data (also referred to as training data). As semiconductor fabrication progresses to advanced technology node processes (e.g., 90 nm to 65 nm to 45 nm to 32 nm and beyond), practical implementation of virtual metrology becomes more constrained by online production needs, such as recipe changes, different process targets, and limited amount of available training data. Existing virtual metrology methods and systems typically focus on accuracy of the virtual metrology forecast results, rather than the practicality of the implementation of virtual metrology in semiconductor fabrication facilities.
Thus, while existing virtual metrology methods and systems are generally adequate for their intended purposes, they are not satisfactory in every aspect.
SUMMARY
One of the broader forms of an embodiment of the present disclosure involves a method of fabricating a semiconductor device. The method includes, collecting a plurality of manufacturing data sets from a plurality of semiconductor processes, respectively; normalizing each of the manufacturing data sets in a manner so that statistical differences among the manufacturing data sets are reduced; establishing a database that includes the normalized manufacturing data sets; normalizing the database in a manner so that the manufacturing data sets in the normalized database are statistically compatible with a selected one of the manufacturing data sets; predicting performance of a selected one of the semiconductor processes by using the normalized database, the selected semiconductor process corresponding to the selected manufacturing data set; and controlling a semiconductor processing machine in response to the predicted performance.
Another one of the broader forms of an embodiment of the present disclosure involves a method of fabricating a semiconductor device. The method includes, providing first manufacturing data that corresponds to a first semiconductor process; transforming the first manufacturing data in a manner so that the first manufacturing data is statistically compatible with second manufacturing data that corresponds to a second semiconductor process, the second semiconductor process being different from the first semiconductor process; predicting performance of the second semiconductor process using the transformed manufacturing data; and controlling a semiconductor fabrication tool based on the predicted performance.
Yet another one of the broader forms of an embodiment of the present disclosure involves a system for wafer result prediction. The system includes: a data collector that collects a plurality of manufacturing data sets from a plurality of semiconductor processes, respectively; and a virtual metrology module that includes: a first data normalization module that normalizes each of the manufacturing data sets in a manner so that statistical differences among the manufacturing data sets are reduced, the normalized manufacturing data sets forming a database; and a second data normalization module that normalizes the database in a manner so that the manufacturing data sets in the normalized database are statistically compatible with a selected one of the manufacturing data sets; wherein the virtual metrology module: predicts performance of a selected one of the semiconductor processes that corresponds to the selected manufacturing data set; and controls a semiconductor processing machine in response to the predicted performance.
BRIEF DESCRIPTION OF THE DRAWINGS
Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
FIG. 1 illustrates a flowchart of a method of modeling a semiconductor process according to various aspects of the present disclosure;
FIG. 2-4 illustrates diagrammatic views of data sets of two different semiconductor processes at various stages of data transformation;
FIG. 5 is a flowchart illustrating a method of carrying out an effect-canceling process of FIG. 1 ;
FIG. 6 illustrates a workflow diagram as an example of prioritizing data sharing and removal; and
FIG. 7 illustrates a block diagram of a fabrication tool, a metrology tool, and a virtual metrology system (VM system) for performing the method of FIG. 1 .
DETAILED DESCRIPTION
It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of the invention. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
FIG. 1 is a flowchart of a method 11 for using virtual metrology in semiconductor fabrication according to an embodiment of the present disclosure. The method begins with block 13 in which a semiconductor fabrication process is performed. The semiconductor fabrication process is associated with one or more fabrication tools, and may include processes such as etching, thermal oxidation, diffusion, ion implantation, RTP (rapid thermal processing), CVD (chemical vapor deposition), PVD (physical vapor deposition), epitaxy, and photolithography. Each fabrication process includes one or more fabrication input process parameters that control one or more fabrication output process parameters. The fabrication input process parameters are associated with fabrication tool settings and may serve as inputs to a fabrication tool. The fabrication output process parameters include observable outcomes or results of the fabrication process. As an example, for an etching process, fabrication input process parameters include etching time and/or etching rate. Fabrication output process parameters of the etching process include etching depth. The etching depth of the etching process can be controlled by adjusting the etching rate or etching time, which may be done by changing settings on the etching tool. It is understood that for any given fabrication process, there may be multiple fabrication input process parameters as well as multiple fabrication output process parameters. In addition, the fabrication input process parameters may also include advanced process control (APC) data, fault detection and classification (FDC) data, and quality control (QC) data.
Mathematically, the relationship between the fabrication output process parameter and the fabrication input process parameter can be expressed as Y=f(X), where the Y variable represents the fabrication output process parameter (e.g. etching depth), and the X variable represents the fabrication input process parameter (e.g. etching rate or etching time). In other words, a fabrication output process parameter is a function of one or more of fabrication input process parameters.
The fabrication output process parameter (i.e., the Y variable) is measured in block 15 of the method 11 with a metrology tool (not illustrated). The measured values of the fabrication output process parameter are then outputted to a block 17 of the method 11 . The fabrication input process parameter (i.e., the X variable) is also outputted by block 13 to block 17 . In block 17 , an effect-canceling process is performed on either the fabrication output process parameter, or the fabrication input process parameter, or both. The effect-canceling process carries out data transformation or data normalization of the fabrication output process parameter or the fabrication input process parameter. In an embodiment, the data transformation includes a mean-shifting process that will be discussed in more detail below.
After the effect-canceling process is performed in block 17 , the method 11 proceeds to block 19 in which more fabrication data is accumulated. The method 11 continues with block 21 in which an effect-retrieving process is performed on the accumulated data. In an embodiment, the effect-retrieving process carries out data transformations on the accumulated data in a manner so that the effect-canceling process is undone or negated. The effect-retrieving process will be discussed in more detail below.
The method 11 continues with block 23 in which a determination is made as to whether enough data had been accumulated. If not enough data has been accumulated, the method 11 proceeds back to block 19 . If enough data has been accumulated, the method 11 proceeds to block 25 , in which a forecast or prediction of the performance of the semiconductor process of block 13 is made using virtual metrology.
FIGS. 2-4 are diagrammatic views of data sets of two different semiconductor processes at various stages of data transformations that are associated with the effect-canceling process and the effect retrieving process of FIG. 1 . Referring to FIG. 2 , a data set 1 includes a plurality of data points that appear as ovals, and a data set 2 includes a plurality of data points that appear as triangles. Each data point in data set 1 corresponds to a measured etching depth of a wafer that is processed in a first processing chamber. Each data point in data set 2 corresponds to a measured etching depth of a wafer that is processed in a second processing chamber. Hence, both data sets 1 and 2 are examples of fabrication output process parameters. It is understood that etching depth is used here merely for purposes of facilitating ensuing discussions, and that data sets 1 and 2 may alternatively represent other process parameters. For example, data set 1 may alternatively represent measured etching depths of wafers that are processed using one etching recipe, and data set 2 may alternatively represent measured etching depths of wafers that are processed using a different etching recipe. In addition, though two data sets are shown here for the sake of simplicity, it is understood that multiple data sets may be used instead.
A mean (or average) of all the data points of data set 1 is illustrated as a broken line and designated at 50 in FIG. 2 . A mean of all the data points of data set 2 is illustrated as a broken line and designated at 55 in FIG. 2 . A reference (or a baseline) is illustrated as a broken line and designated at 60 in FIG. 2 . In an embodiment, the reference 60 is the performance target (desired etching depth target) for both of the data sets 1 and 2 . In another embodiment, the reference 60 may be a global or overall mean value of all of the data points of the data sets 1 and 2 .
An offset 70 exists between the mean 50 and the reference 60 , and an offset 75 exists between the mean 55 and the reference 60 . The offsets 70 and 75 may also be referred to as “effects”. These effects 70 and 75 are caused by the fact that the data sets 50 and 55 come from (or are associated with) different processing chambers. In alternative embodiments, the effects may be caused by different processing recipes, different layers, or different products. The existence of these effects puts a constraint on the amount of available training data for each virtual metrology model. In more detail, a virtual metrology model allows a prediction to be made as to the future performance of a particular semiconductor fabrication process based on previously collected data. In other words, using the previously collected data (training data) from relevant processing tools, one can forecast the electrical and physical parameters of wafers, without actually needing to make those measurements. In this manner, virtual metrology allows for the reduction and even elimination of the direct measurements.
However, accurate virtual metrology models often require large amounts of training data. Each fabrication process has its own associated training data. For example, wafers being processed in different chambers may require separate virtual metrology models, even if the product, the layer, and the processing recipes are the same. As another example, wafers that are of the same product, the same layer, and that are being processed in the same processing chamber may also require separate virtual metrology models if the processing recipes are different. As such, based on the number of permutations with respect to different products, different layers, different processing recipes, and different processing chambers, a large number of virtual metrology models may need to be established to accurately forecast the performance of all the fabrication processes. This is because each fabrication needs its own virtual metrology model for the fabrication process performance to be accurately forecast. To establish an accurate virtual metrology model, a large amount of training data needs to be provided.
However, a forecast on the performance of a fabrication process typically needs to be made with a smaller quantity of available training data. Further, the calculations for the forecast need to be made quickly, which cannot happen if data collection is still underway. As such, existing virtual metrology techniques are constrained by the lack of available training data and the time that is needed for calculations to be made (since collecting large amounts of data takes a long time). In comparison, the embodiments disclosed herein resolve issues outlined above by enabling the sharing of data between similar data sets, as discussed in detail below.
Referring now to FIG. 3 , an effect-canceling process is performed to transform each data point of the data sets 1 and 2 . The effect-canceling process shifts the data set 1 “downward” until its mean 50 ( FIG. 2 ) is aligned with the reference 60 , and the effect-canceling process shifts the data set 2 “upward” until its mean 55 ( FIG. 2 ) is also aligned with the reference 60 . The shifting of data sets 1 and 2 in effect transforms or normalizes each of the data points of the data sets 1 and 2 in a manner so that the effects are canceled. Thus, the data sets 1 and 2 are now statistically compatible with each other and may be shared with each other for purposes of establishing a single virtual metrology model. Stated differently, the transformed (or normalized) data sets 1 and 2 form a larger data set that contains more statistically compatible training data than either data sets 1 or 2 . This larger data set can also be referred to as a data base. As discussed above, FIGS. 2 and 3 only show two data sets 1 and 2 for the sake of simplicity, and that multiple data sets may be data transformed or normalized in a similar fashion. As more data sets are integrated into the overall database, the available training data can be accumulated more quickly.
Referring now to FIG. 4 , an effect-retrieving process is performed on all the data points in the overall database formed by data sets 1 and 2 . The effect-retrieving process shifts all the data points “upward” until the global mean of the database is aligned with the mean 50 ( FIG. 2 ) of data set 1 . At this time, the virtual metrology model associated with data set 1 has the data points from data set 2 as available training data, in addition to the data points from data set 1 . In other words, after the effect-retrieving process is performed, the shifted data set 2 becomes sufficiently statistically compatible with data set 1 . Hence, a virtual metrology forecast can be made more quickly. For example, suppose a virtual metrology model for the fabrication process associated with data set 1 requires 60 wafers of data as sufficient training data. Data sets 1 and 2 each contain 30 wafers of data. Using traditional virtual metrology techniques, the fabrication process associated with data set 1 would have to accumulate more data before an accurate virtual metrology forecast can be made.
Here, since the 30 wafers of data of data set 2 can also be used as valid training data for the fabrication process associated with data set 1 , the training data now contains 60 wafers of data, and as such is sufficiently large for an accurate virtual metrology forecast to be made regarding the future performance of the fabrication process associated with data set 1 . It is understood that as more data sets are shared, a virtual metrology forecast can be made more quickly. For example, in an embodiment where 10 different data sets are shared into the same database, then only 6 wafers of data for each data set would result in 60 wafers of total available training data, and that a virtual metrology forecast can be made for any of the 10 fabrication processes associated with the 10 data sets. It is also understood that although the effect-retrieving process in FIG. 4 shows shifting the database “upwards” to align the reference 60 with the mean 50 of data set 1 , the effect-retrieving process may shift all the data points “downward” until the reference of the database is aligned with the mean 55 ( FIG. 2 ) of data set 2 , if a virtual metrology forecast needs to be made regarding the future performance of the fabrication process associated with data set 2 .
FIG. 5 is a flowchart illustrating an example method 110 of carrying out the effect-canceling process of FIG. 1 with respect to a fabrication input process parameter. For the sake of facilitating ensuing discussions, etching processes using advanced process control (APC) are discussed below. The method 110 begins with block 120 in which an average etching rate is estimated. In etching processes, etching time can be used in the APC process to tune the etching depth. Here, a plurality of etching processes are performed, and they may have varying targets of etching depths and etching rates. Etching rate in general is defined as etching depth per unit etching time. For the plurality of etching processes, the average etching rate is expressed using the following equation:
ER _ = ∑ i = 1 n ( depth i - depth _ ) ( APC i - APC _ ) n
where ER represents etching rate, and depth represents etching depth, APC represents etching time, and n represents the number of etching processes.
The method 110 continues with block 125 in which an APC modification term for target migration is calculated. The APC modification term is expressed as ΔAPC i and is calculated using the following equation:
Δ APC i = depth Newlot Target - depth i Target ER _
In other words, a new wafer lot associated with a new etching process has a target etching depth. The APC modification term is calculated by taking the difference between the target etching depth of the new wafer lot and the target etching depth of existing wafer lots, and then dividing the difference by the average etching rate. The APC modification term represents an amount of etching time that needs to be adjusted so that the new wafer lot will reach the target etching depth.
The method 110 continues with block 130 in which the APC process is adjusted based on the calculations performed in block 125 . The equation for calculating the adjusted APC term is as follows:
APC i adjusted =APC i +ΔAPC i
The adjusted APC term represents the amount of etching time now needed to ensure that the etching depth of the new wafer lot will reach the new target depth. It is understood that the etching time is not actually adjusted in fabrication processing. Rather, the method 110 derives an estimated value that the etching time would have to be adjusted, so that fabrication process parameters like etching time and etching depth from different wafer lots would be become statistically compatible enough to be shared.
In situations where shared data sets come from multiple sources—for example, different chambers and different recipes—the present embodiment also offers a method to prioritize which data sets should be shared first and how the shared data needs to be removed once enough data has been accumulated. FIG. 6 illustrates an example embodiment of such method as a workflow diagram 140 . The workflow diagram includes rows 150 - 154 and columns 157 - 159 . The rows 150 - 154 denote different stages of data sharing, which are initialization, propagation, removal stage I, removal stage II, and normal, respectively. The Columns 157 - 159 denote three different processing chambers, which are chamber 1 , chamber 2 , and chamber 3 , respectively.
The rows 150 - 154 and columns 157 - 159 form cells 160 - 174 . Within each cell, “IMKT” represents data associated with one recipe, and “IMST” represents data associated with a different recipe. A number following IMKT indicates the number of wafers on which fabrication data associated with the IMKT recipe have been collected. Two numbers follow IMST. The first number indicates the number of wafers on which fabrication data associated with the IMST recipe have been collected. The second number (italicized) also indicates the number of wafers on which fabrication data associated with the IMST recipe have been collected, though that fabrication data comes from a different chamber. To illustrate, at the initialization stage 150 , in cell 160 , IMKT=20, and IMST=0+0. This means that for chamber 1 , there are 20 wafers of data available for the IMKT recipe, but no data (actual data or shared data) is available for the IMST recipe. Nevertheless, a virtual metrology forecast can still be made for the IMST recipe by using the IMKT recipe as baseline (or initialization) data. Alternatively stated, since no concrete data is available for the IMST process, the 20 wafers of IMKT data can be used as substitute for the IMST data since they are similar. It is understood that the IMKT data has already been effect-canceled and effect-retrieved at this point.
After the initialization stage 150 is the propagation stage 151 . In the first line of cell 163 , IMKT=20, which means the 20 wafers of IMKT data is still shared. IMST=1+0, which means one wafer of IMST data has actually been collected on the wafer in chamber 1 , but there is no shared IMST data that comes from chambers 2 and 3 . Meanwhile, the IMST data collected by the wafer in chamber 1 is shared to cells 161 and 162 . As such, the first lines of cells 164 and 165 both show IMST=0+1, where the 1 indicates one wafer of IMST data that is associated with chamber 1 and shared to cells 164 and 165 .
The second line of cell 164 shows IMST=1+1, meaning that a wafer of IMST data associated with the chamber 2 has been collected. This data is then shared to cells 163 and 165 , as reflected by the second line of cell 163 showing IMST=1+1, and the second line of cell 165 showing IMST=0+2. Although not shown, IMST data is next collected for chamber 3 , which will then be shared to cells 163 and 164 . The process discussed above continues until the last line of cells 163 - 165 , at which point cell 163 contains 20 wafers of shared IMKT data, 14 wafers of actual IMST data associated with chamber 1 , and 26 wafers of shared IMST data associated with chambers 2 and 3 . Cell 164 contains 20 wafers of shared IMKT data, 13 wafers of actual IMST data associated with chamber 2 , and 27 wafers of shared IMST data associated with chambers 1 and 3 . Cell 165 contains 20 wafers of shared IMKT data, 13 wafers of actual IMST data associated with chamber 3 , and 27 wafers of shared IMST data associated with chambers 2 and 3 .
At this time, a relatively accurate virtual metrology forecast can be made for the particular fabrication process associated with each cell, since each cell now has a total of 60 wafers of data. For example, a virtual metrology model can be established for wafers that are processed in chamber 1 and using the IMST recipe, even though only 14 wafers of such type of data have actually been collected. 20 out of the 60 wafers of data come from IMKT data, which are shared into cell 163 and serve as data that is statistically compatible with IMST data. 26 out of the 60 wafers of data are IMST data but come from other processing chambers 2 and 3 . Thus, as discussed above, it can be seen that the data sharing approach enables one to make virtual metrology forecasts more quickly than traditionally possible. Further, for the sharing of the IMKT data and the IMST data associated with other chambers to occur, the effect-canceling and effect-retrieving processes discussed above with reference to FIGS. 1-4 are performed first, since the effect-canceling and effect-retrieving processes make the shared data become statistically compatible with the actual data.
Following the propagation stage 151 is the removal stage I 152 . In removal stage I 152 , the shared IMKT data are gradually purged or removed, as more IMST data is collected. The reason for the removal of IMKT data is that, between shared IMKT data and shared IMST data associated with a different chamber, the IMKT data is less statistically relevant to the actual IMST data on which a virtual metrology forecast is to be made. Alternatively stated, the IMST data associated with chambers 2 and 3 will more accurately represent IMST data associated with chamber 1 , compared to the IMKT data. Thus, as seen in cell 166 , IMKT=19, meaning that 1 wafer of IMKT data is removed. At the same time, IMST=15+26, meaning that 1 more wafer of IMST data associated with chamber 1 has been collected. The total number of wafers of data is still 60, and the virtual metrology model established using this batch of 60 wafers of data will make a more accurate virtual metrology forecast than the model established using the 60 wafers of data in cell 163 . The purging of the IMKT data continues until the end of the removal stage I 152 , at which point there are no more shared IMKT data.
The removal stage II 153 follows the removal stage I 152 . In this stage, the shared IMST data associated with other chambers are removed. As an example, in cell 169 , IMKT=0 (indicating no shared IMKT data), and IMST=35+25. Compare this to the last line of cell 166 , in which IMST=34+26, it can be seen that the first number following IMST has been incremented, while the second number following IMST has been decremented. This means that as 1 more wafer of IMST data associated with chamber 1 is collected, 1 wafer of data associated with chambers 2 or 3 is removed from cell 169 . The removal of IMST data associated with other chambers continues until stage normal 154 , where the only data left in each cell 172 - 174 is the IMST data associated with its respective chamber. At this stage, since enough actual data exists for each virtual metrology model, there is no need to have data sharing, though in other embodiments data sharing can still be done if desired.
It is understood that the workflow diagram 140 is not limited to the sharing and purging of data with respect to different processing chambers and different recipes and may alternatively be used to share and purge data with respect to different products or different layers of the same product.
FIG. 7 is a high level block diagram showing a fabrication tool, a metrology tool, and a virtual metrology system (VM system) for performing the method of FIG. 1 . A VM system 200 includes a virtual metrology module (VM module) 201 that is operable to perform actions including manipulating information, receiving information, storing information, and transferring information. The information may include, for example, commands, process parameters such as those parameters used in process recipes, manufacturing data, advanced process control parameters, and fabrication tool status. The VM module 201 includes an effect-canceller module 202 and an effect-retriever module 203 . The effect-canceller module 202 performs data transformations necessary to carry out the effect-canceling process discussed above with reference to FIGS. 1-3 . For example, the effect-canceller module may be operable to perform a mean-shifting process on its input data. The effect-retriever module 203 performs data transformations necessary to carry out the effect-retrieving process discussed above with reference to FIGS. 1 and 4 . The effect-retriever module may also be operable to perform a mean-shifting process on its input data. The VM system 200 further includes a data collector module 204 and a communication interface module 210 .
A metrology tool 212 and a fabrication tool 214 are coupled to the VM system 200 . The metrology tool 212 may include electrical, optical, and/or analytical tools, such as microscopes, micro-analytical tools, line-width measurement tools, mask and reticle defects tools, particle distribution tools, surface analysis tools, stress analysis tools, resistivity and contact resistance measurement tools, mobility and carrier concentration measurement tools, depth measurement tools, film thickness measurement tools, gates oxide integrity test tools, C-V measurement tools, focused ion beam, and other test and measurement tools.
The fabrication tool 214 may include, etching tools, chemical vapor deposition (CVD) tools, physical vapor deposition (PVD) tools, atomic layer deposition (ALD) tools, thermal oxidation tools, ion implantation tools, chemical mechanical polishing (CMP) tools, rapid thermal annealing (RTA) tools, photolithography tools, or other proper semiconductor fabrication tools.
The metrology tool 212 and the fabrication tool 214 respectively output wafer data and tool data to the data collector module 204 , which then sends the wafer data and tool data to the VM module 201 for analysis and modeling. The wafer data and the tool data may be collectively referred to as manufacturing data. The wafer data includes the fabrication output process parameters (i.e., the Y variable) discussed above with reference to FIG. 1 . The fabrication output process parameters may be wafer parameters such as trench depth, sheet resistance, reflectivity, stress, particle density, critical dimension, leakage current, and threshold voltage, to name a few. The wafer data may further include other data such as wafer ID and product type.
The tool data includes the fabrication input process parameters (i.e., the X variable) discussed above with reference to FIG. 1 . The fabrication input process parameters may include the setting values of process parameters, which may be changed by adjusting the settings of the fabrication tool 214 . In a CMP process, for example, the fabrication input process parameters may include polishing pressure, platen rotational speed, slurry distribution rate, slurry temperature, and wafer temperature. In PVD, as another example, the fabrication input process parameters may include heater temperature, wafer temperature, radio frequency (RF) bias reflected power, RF side reflected power, RF top reflected power, chamber pressure, gas partial pressures, and chuck voltage. The fabrication input process parameters may also include other parameters not included in a process recipe such as sputtering target thickness and spacing between the target and the wafer for the PVD tool. The tool data may further include other data such as tool ID, tool maintenance history, and material specification (such as slurry composition in CMP and sputtering target in PVD).
A semiconductor wafer, either individually or in batch, is processed through various fabrication process steps. One process step may be performed in the fabrication tool 214 . Other process steps may be performed in other fabrication tools. The fabrication tool 214 may be programmed, set, and configured according to a process recipe when the wafer is processed therein, for example by adjusting the fabrication input process parameters for the fabrication tool. The process recipe may define a plurality of sub-steps. For example, a PVD tool recipe may define the following sub-processes: gas, ramp, stabilization, deposition, and pump-down. Each sub-process may be defined with a certain time duration and may set various hardware parameters to certain levels. After the wafer completes the process step in the fabrication tool 214 according to the process recipe, one or more of the metrology tools 212 may be utilized to test and measure the wafer to get wafer data or results. The wafer data and tool data are then collected by the data collector 204 from the metrology tool 212 and the fabrication tool 214 , respectively, and stored in memory in the VM system 200 . The data stored in memory may later be retrieved by the VM metrology module 201 and be processed by the effect-canceller module 202 and the effect-retriever module 203 .
Performance of a semiconductor process is predicted using the VM module 201 . For example, the wafers may be processed by the fabrication tool 214 and the process parameters have been set in accordance with the specified process recipe. Additionally, current tool data and wafer can be collected in real-time and routed to pertinent modules of the VM system 200 for analysis. The VM module 201 makes a prediction on a process result (or wafer result) of the semiconductor process based on the current data in conjunction with the previous data that is stored in memory.
The predicted wafer result may be sent out to pertinent engineers or customers of the fab. Further, the predicted wafer result may be fed forward to control subsequent semiconductor processes or may be fed backward to tune the current semiconductor process. Additionally, the predicted wafer result may be used to adjust the process recipe for subsequent wafers. Accordingly, the VM system 200 may be used to substitute for the physical metrology operations that are performed by an engineer using metrology tools (e.g., metrology tool 212 ) in order to measure actual wafer results. Thus, the VM system 200 can be implemented in Computer Integrated Manufacturing (CIM) applications so that the predicted results may used to determine whether the wafers are within design specifications for virtual wafer acceptance testing (WAT).
For example, the communication interface 210 may communicate the predicted wafer result within the semiconductor fabrication environment. For example, the predicted wafer result may be sent to engineers 216 for evaluation, production monitor, and/or process improvement. The engineers 216 may communicate with the VM system 200 through the communication interface 210 . The communication interface 210 may even provide an alarm to the engineers 216 when the predicted wafer results are out of a predefined range, has apparent shifting, or has other serious changes. The predicted wafer result may be sent to a data control center such as a manufacturing execution system (MES) system wherein the predicted wafer result may be further processed, organized, and distributed for data monitoring, evaluation, analysis, and/or control such as statistical process control (SPC). The predicted wafer result may be sent to a fabrication tool at a next semiconductor process, wherein the process recipe and process parameters may be adjusted to compensate for any drifting and/or shifting from the current semiconductor process for optimized wafer quality, performance, and yield.
The VM system 200 of FIG. 2 serves as an example to the present disclosure. Each module thereof may include software and/or hardware to implement its functions. For example, the VM module 201 may include hardware such as computer and memory for operation and storage. The VM module 201 may also include software for providing an operating environment. The VM system 200 may further include a database that stores all process parameters, manufacturing data, pool of functional transformations, and optimization algorithms. Each module may be well configured, connected to other modules and other components of the semiconductor fabrication environment. The VM system 200 may be configured and organized in different ways such as with less or more modules without departure from the spirit of the present disclosure.
The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure. | The present disclosure provides a method of fabricating a semiconductor device. The method includes collecting a plurality of manufacturing data sets from a plurality of semiconductor processes, respectively. The method includes normalizing each of the manufacturing data sets in a manner so that statistical differences among the manufacturing data sets are reduced. The method includes establishing a database that includes the normalized manufacturing data sets. The method includes normalizing the database in a manner so that the manufacturing data sets in the normalized database are statistically compatible with a selected one of the manufacturing data sets. The method includes predicting performance of a selected one of the semiconductor processes by using the normalized database. The selected semiconductor process corresponds to the selected manufacturing data set. The method includes controlling a semiconductor processing machine in response to the predicted performance. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to a coated cutting tool for chipforming machining. The coating includes at least one alumina (Al 2 O 3 ) layer characterized by fine, equiaxed grains.
DESCRIPTION OF THE RELATED ART
[0002] In the description of the background of the present invention that follows reference is made to certain structures and methods, however, such references should not necessarily be construed as an admission that these structures and methods qualify as prior art under the applicable statutory provisions. Applicants reserve the right to demonstrate that any of the referenced subject matter does not constitute prior art with regard to the present invention.
[0003] Cemented carbide cutting tools can be coated with various types of Al 2 O 3 layers by using Chemical Vapour Deposition (CVD), e.g., pure κ-Al 2 O 3 , mixtures of κ- and α-Al 2 O 3 , coarse grained α-Al 2 O 3 , and fine grained textured α-Al 2 O 3 have been commercially available for years generally in multilayer combinations with other metal carbide and/or nitride layers, the metal being selected from transition metals of the IVB, VB and VIB groups of the Periodic Table.
[0004] Al 2 O 3 crystallizes in several different phases: α, κ, γ, δ, θ etc. The two most frequently occurring phases of CVD-produced wear resistant Al 2 O 3 layers are the thermodynamically stable α-phase and the metastable κ-phase, or a mixture thereof. Generally, the κ-phase exhibits a grainsize in the range 0.5-3.0 μm and the grains predominately grow through the whole coating forming a columnar type coating morphology. Furthermore, the κ-Al 2 O 3 layers are free from crystallographic defects and also free from micropores and voids.
[0005] Coarse-grained (3-6 μm) α-Al 2 O 3 often possesses porosity and crystallographic defects, while fine-grained textured α-Al 2 O 3 are free of defects with very pronounced columnar-shaped grains.
[0006] In U.S. Pat. No. 5,674,564 is disclosed a method of growing a fine-grained κ-alumina layer by employing a low deposition temperature and a high concentration of a sulphur dopant.
[0007] In U.S. Pat. No. 5,487,625 a method is disclosed for obtaining a fine grained, (012)-textured α-Al 2 O 3 layer consisting of columnar grains with a small cross section (about 1 μm).
[0008] In U.S. Pat. No. 5,766,782 a method is disclosed for obtaining a fine-grained (104)-textured α-Al 2 O 3 layer.
[0009] As mentioned above, all Al 2 O 3 layers produced by the CVD technique possess a more or less columnar-like grainstructure. An Al 2 O 3 layer with an equiaxed grainstructure is, however, expected to show some favorable mechanical properties, e.g.—resistance to crack propagation, as compared to a layer with a columnar grainstructure. One well-known and possible technique to avoid columnar grain growth is to deposit a so-called multilayer structure in which the columnar growth of Al 2 O 3 is periodically interrupted by the growth of a thin, 0.1-1 μm second layer such as disclosed in U.S. Pat. No. 4,984,940. The second layer should preferably have a different crystal structure or at least different lattice spacings in order to be able to initiate renucleation of the first layer. One example of such a technique is when the Al 2 O 3 growth periodically is interrupted by a short TiN deposition process resulting in a (Al 2 O 3 +TiN)xn multilayer structure with a thickness of the individual TiN layers of about 0.1-1 μm (see, e.g.—Proceedings of the 12th European CVD Conference, page pr.8-349). However such multilayer structures very often suffer from a low adherence between the two different types of layers.
SUMMARY OF THE INVENTION
[0010] It is the object of the present invention to provide onto a hard substrate, or preferably onto a hard substrate coated with a TiC x N y O z layer, at least one single phase α-Al 2 O 3 layer with a microstructure which is different from the prior art columnar α- or κ-Al 2 O 3 CVD layers mentioned above. It is also the object of the present invention to provide a high performance tool coating comprising the invented Al 2 O 3 layer.
[0011] It is a further object of the invention to provide an alumina coated cutting tool insert with improved cutting performance in steel, stainless steel, cast iron and in particular nodular cast iron.
[0012] According to one aspect, the present invention provides a cutting tool comprising a body of sintered cemented carbide, cermet, or ceramic superhard material, the body comprising a surface, and a hard and wear resistant coating on at least a portion of the surface, said coating comprising: one or more refractory layers of which at least one layer essentially consists of α-Al 2 O 3 , said α-Al 2 O 3 layer having equiaxed grains with an average grainsize of <1 μm and further containing striated zones containing >5 at % titanium, but no nitrogen or carbon.
[0013] According to another aspect, the present invention provides a method of coating a body with an α-alumina layer comprising: (i) bringing the body into contact with a hydrogen carrier gas containing one or more halides of aluminum and a hydrolyzing and/or oxidizing agent while the body is at a temperature of 950-1000° C.; (ii) maintaining the oxidation potential of the CVD-reactor atmosphere prior to the nucleation of Al 2 O 3 at a low level, using a total predetermined concentration of oxidizing species; (iii) starting Al 2 O 3 growth by introducing the following gases into the reaction chamber: AlCl 3 , HCl and CO 2 ; (iv) adding a sulphur dopant after 20-60 min; (v) repeatedly stopping the CO 2 , AlCl 3 , HCl and the sulphur dopant for intervals of 10-50 min during which TiCl 4 is allowed to enter the reactor for 1-10 min in a concentration of 1-10%; and (vi) then reintroducing AlCl 3 , HCl, CO 2 and the sulphur dopant, in that order.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0014] [0014]FIG. 1 a is a Scanning Electron Microscope (SEM) micrograph of an Al 2 O 3 layer according to the present invention.
[0015] [0015]FIG. 1 b is a SEM micrograph at high magnification of a polished cross-section of an Al 2 O 3 layer according to the present invention.
[0016] [0016]FIG. 2 a is a SEM micrograph prior art Al 2 O 3 layer.
[0017] [0017]FIG. 2 b is a SEM micrograph at high magnification of a polished cross-section of an Al 2 O 3 layer according to the prior art.
[0018] [0018]FIG. 3 a is a SEM micrograph of a prior art multilayer Al 2 O 3 /TiN coating.
[0019] [0019]FIG. 3 b is a SEM micrograph at high magnification of a polished cross-section of an Al 2 O 3 /TiN multilayer according to the prior art.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Surprisingly it has been found that a non-columnar α-Al 2 O 3 layer can be deposited by interrupting the Al 2 O 3 growth process by obstructing the flow of the CO 2 , AlCl 3 , HCl and H 2 S gases to the reactor chamber and then immediately introducing TiCl 4 (H 2 is already present in the reactor) for a short period of time. When the reactant gases AlCl 3 , HCl, CO 2 and H 2 S are allowed to reenter the reactor again in that mentioned order, renucleation of Al 2 O 3 will take place. The duration of the TiCl 4 treatment as well as the TiCl 4 concentration are important parameters which must be optimized in order to obtain the desired result. If the TiCl 4 concentration is too low and/or treatment time is too short, the renucleation of the Al 2 O 3 layer will not be sufficiently dense to cover a sufficient portion of the whole coating surface. If, on the other hand, the TiCl 4 concentration is too high and/or the treatment time is too long, the cohesion between the Al 2 O 3 grains will be too weak resulting in a low quality coating.
[0021] The method of the present invention thus relates to the coating of a body with an α-alumina layer during which the body is brought in contact with a hydrogen carrier gas containing one or more halides of aluminum and a hydrolyzing and/or oxidizing agent at temperature of the body between 950 and 1000° C. The oxidation potential of the CVD-reactor atmosphere prior to the nucleation of Al 2 O 3 is kept at a low level keeping the total concentration of H 2 O, water vapor, or other oxidizing species, preferably less than 5 ppm. The Al 2 O 3 growth is started by sequencing the following gases AlCl 3 , HCl and CO 2 (H 2 is already present in the reactor) into the reaction chamber in that mentioned order or by using the start-up procedures described in any of the prior art patents, U.S. Pat. No. 5,487,625 and U.S. Pat. No. 5,766,782, in order to achieve different textures of the Al 2 O 3 layer. After 10-60 minutes a sulphur dopant, preferably H 2 S is added to the gas mixture. The flow of the CO 2 , AlCl 3 , HCl gases and the sulphur dopant are periodically interrupted at intervals of 10-50 minutes and 1-10 % (of the hydrogen flow) TiCl 4 is allowed to enter the reactor for a period of 1-10 minutes and then again replaced by AlCl 3 , HCl, CO 2 and the sulphur dopant in that mentioned order. This procedure is repeatedly carried out in order to obtain a striated, bimodal α-Al 2 O 3 layer structure with the desired grainsize and texture.
[0022] In contrast to the columnar grains of prior art Al 2 O 3 layers, the grains of the Al 2 O 3 layers according to the present invention are essentially equiaxed with a bimodal structure which is a mixture of small and large grains. The obtained grainsize and the distribution of the same are dependent on the number of TiCl 4 treatments carried out. The more frequently the Al 2 O 3 process is interrupted and the Al 2 O 3 surface is treated with TiCl 4 , the smaller the Al 2 O 3 grains will be. The large Al 2 O 3 grains have an average grain size d c <1 μm and the small Al 2 O 3 grains, 0.1<D f <⅓d c .
[0023] The grainsize in the α-Al 2 O 3 layer can be determined from a SEM top-view micrograph at about 4000X magnification. Such a micrograph of an Al 2 O 3 layer surface according to the present invention is shown in FIG 1 a . In FIG. 2 a and 3 a , the micrographs of prior art Al 2 O 3 layers are shown. The size and the shape of the grains can easily be observed. Furthermore, the striated zones in the α-Al 2 O 3 layer which contain titanium and oxygen are visible in a polished cross section at 4000-6000 X magnification. These striated zones which do not contain any carbon or nitrogen may also contain some aluminum. The striated zones are preferably <0.2 μm thick and the number of striated zones per μm Al 2 O 3 layer should be 1-10. The zones may be closely linked together but in some cases almost resembling a multilayer structure. The presence of these striated zones in the Al 2 O 3 structure evidently limits the Al 2 O 3 graingrowth and makes renucleation possible without the negative effect of fully intermediate or intervening layers.
[0024] By selecting appropriate conditions for the initial growth of the Al 2 O 3 layer, e.g.—according to the procedures in patents U.S. Pat. No. 5,487,625 and U.S. Pat. No. 5,766,782, Al 2 O 3 layers textured in the (012)-, (024)- or (104)-directions with a texture coefficient TC>1.3 can be deposited.
[0025] The texture Coefficient, TC, is defined as:
TC ( hkl ) = I ( hkl ) I o ( hkl ) { 1 n ∑ I ( hkl ) I o ( hkl ) } - 1
[0026] where
[0027] I(hkl)=measured intensity of the (hkl) reflection
[0028] I o (hkl)=standard intensity of the ASTM standard powder
[0029] pattern diffraction data
[0030] n=number of reflections used in the calculation, (hkl)
[0031] reflections used are: (012), (104), (110), (113), (024), (116)
[0032] The coated body may comprise a cutting tool with a substrate of cemented carbide, cermet or a ceramic superhard material and a coating consisting of a hard wear resistant material and in said coating at least one layer is a single phase α-Al 2 O 3 layer according to the present invention, and said single phase (α-Al 2 O 3 layer having a thickness in the range 0.5-25 μm. The other layers in the coating structure may be TiC or related carbide, nitride, carbonitride, oxycarbide and oxycarbonitride of a metal selected from the Groups IVB, VB, and VIB of the Periodic Table, the elements B, Al and Si and/or mixtures thereof. Such other layers may be deposited by CVD, PACVD (Plasma CVD), PVD (Physical Vapour Deposition) or MT-CVD (Moderate Temperature CVD). At least one of such other layers is in contact with the substrate. The total thickness of the coating of the cutting tool can vary between 1 and 30 μm.
Example
[0033] A) Cemented carbide cutting inserts in style CNMG 120412-KM with the composition 6 weight-% Co and balance WC were coated with a 5 μm thick layer of TI(C,N) using the MTCVD-technique with TiCl 4 , H 2 , N 2 and CH 3 CN as process gases. In subsequent process steps during the same coating cycle, a 0.5 μm TiC x N y O z layer with an approximate composition corresponding to x=0.5, y=0.3 and z=0.2 was deposited followed by a 6 μm thick layer of α-Al 2 O 3 deposited according to the invented coating process. Prior to the nucleation of the Al 2 O 3 the oxidation potential of the carrier gas H 2 (only gas present in the reactor) i.e. the water vapor concentration, was explicitly set to a low level, i.e.—less than 5 ppm.
[0034] Then the first Al 2 O 3 layer step I was started up. The process conditions during the Al 2 O 3 deposition were as below:
Step 1 2 3 4 CO2: 4% 4% 0% 4% AlCl3: 4% 4% 0% 4% H2S — 0.2% 0% 0.2% HCl 1.5% 5% 0% 5% H2: balance balance balance balance TiCl4 — — 5% Pressure: 60 mbar 60 mbar 60 mbar 60 mbar Temperature: 1000° C. 1000° C. 1000° C. 1000° C. Duration: 30 min 20 min 5 min 20 min
[0035] The Al 2 O 3 layer was deposited by proceeding through step 1 , 2 and 3 and then looping between step 3 and step 2 nine times and finishing the process by step 4 . Hence, the Al 2 O 3 -process was interrupted and treated with TiCl 4 /H 2 altogether ten times.
[0036] XRD-analysis of the deposited α-Al 2 O 3 showed a strongly textured structure with a texture coefficient TC(012) of 1.7 of the (012) planes and TC(024) of 1.5 of the (024) planes.
[0037] From the SEM-micrographs taken from the top surface, similar to Fig 1 a , the grainsize was determined. The coarse grains had an average grainsize of 0.9 μm and the fine grains had an average grainsize of 0.3 μm.
[0038] B) The cemented carbide substrate of A) was coated with Ti(C,N) (5 μm), a 0.5 μm TiC x N y O z layer and Al 2 O 3 (6 μm) as set forth in A) except for that the Al 2 O 3 process was carried out according to prior art technique, i.e.—the same process as described under A.) except for that the TiCl 4 /H 2 -treatments were excluded and an Al 2 O 3 process time of 290 min. This resulted in an Al 2 O 3 layer consisting essentially of the κ-Al 2 O 3 phase with an average grainsize of about 2 μm, FIG. 2 a.
[0039] C) The cemented carbide substrate of A) was coated with Ti(C,N) (5 μm), a 0.5 μm TiC x N y O z layer and a 6 μm of multilayered Al 2 O 3 coating on top as set forth in A) except for that step 3 was substituted by a prior art TiN-process step. The process parameters for this TiN-step were as follow: 2% TiCl 4 , 40% N 2 , 58% H 2 and a process time of 3 min. This resulted in a multilayer coating consisting of 11 layers of Al 2 O 3 and 10 thin layers of TiN. The Al 2 O 3 layer was determined to consist of the κ-phase.
[0040] Coated tool inserts from A), B) and C) were all wet blasted with 150 mesh Al 2 O 3 powder in order to smooth the coating surfaces.
[0041] The cutting inserts were then tested with respect to edge line and rake face flaking in a facing operation in nodular cast iron. The shape of the machined work piece was such that the cutting edge is intermitted twice during each revolution.
[0042] Cutting data:
[0043] Speed=170 m/min,
[0044] Cutting depth=2.0 mm and
[0045] Feed=0.1 mm/rev.
[0046] The inserts were run one cut over the face of the work piece. This test is very decisive and demanding when cutting nodular cast iron. The percentage of the edge line in cut that obtained flaking into the carbide substrate was recorded for each insert tested as well as to what extent flaking occurred on the rake phase of the cutting insert.
[0047] The results are expressed in the table below as an average value of the four inserts.
Flaking Edge line Rake face A) α-Al 2 O 3 0% only spot-wise single phase/striated flaking of the (acc. to invention) Al 2 O 3 layer B) κ-Al 2 O 3 90% severe Al 2 O 3 - (prior art) Flaking C) multilayer Al 2 O 3 /TiN 70% Flaking between (prior art) TiN and Al 2 O 3 layers
[0048] While the present invention has been described by reference to the above-mentioned embodiments, certain modifications and variations will be evident to those of ordinary skill in the art. Therefore, the present invention is to limited only by the scope and spirit of the appended claims. | According to the present invention there is provided a body at least partially coated with one or more refractory layers of which at least one layer essentially consist of αAl 2 O 3 . Said αAl 2 O 3 layer consists of essentially equiaxed grains with an average grain size of <1 μm and with a bimodal grain size distribution with coarser grains with an average grainsize in the interval 0.5-1 μm and finer grains with an average grainsize of <0.5 μm. The Al 2 O 3 layer further contains striated zones containing titanium (>5 at %) but no nitrogen or carbon. This particular microstructure is obtained by temporarily stopping the gases needed for the growth of the Al 2 O 3 layer and introducing TiCl 4 . | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improvement of a noncontact type tonometer which is designed to measure intraocular pressure of a subject's eye by optically detecting transfiguration of the eye caused by discharging a fluid toward the eye without bringing the tonometer into contact with the eye.
2. Description of the Prior Art
This kind of noncontact type tonometer, for example, as shown in Japanese Patent Application Early Laid-open Publication No. Sho 56-6772, comprises a gas discharging device for transfiguring the eye by discharging gas toward the eye, a light source for illuminating the eye with detecting light, and a corneel transfiguration detecting means for receiving reflected light from the eye to detect the corneel transfiguration of the eye.
If the discharge pressure of the gas gradually increases, a surface of the cornea is transfigured, so that the quantity of the reflected light from the cornea temporarily increases and reaches its peak when the cornea is transfigured into an applenation state (a flat state). If the discharge pressure further increases, the surface of the cornea becomes concave and then the reflected light quantity decreases.
In a conventional noncontact type tonometer, at the time when the quantity of the reflected light from the cornea exceeds a predetermined reference level, namely before the cornea reaches an applanation state, the operation of the gas discharging device is stopped. After the operation of a piston of the gas discharging device is stopped, the discharge pressure increases for a while by inertia of the piston and then decreases. In a case where the intraocular pressure of the eye is normal, since the cornea is transfigured into the applanation state and the peak of reflected light quantity is detected when the pressure within the gas discharging device is increasing because of the inertia, the intraocular pressure can be calculated from the air pressure obtained when the peak is detected.
However, in the conventional tonometer, so to speak, with the expectation that the cornea is transfigured into the applanation state during the rise in pressure caused by the inertia of the piston, the operation of the gas discharging device is stopped. Accordingly, if the intraocular pressure of the eye is much higher than normal and an increase in quantity of the discharge pressure needed for the reflected light quantity to exceed the reference level and reach the applanation state is also larger than normal, the air pressure within the gas discharging device decreases before the cornea is transfigured into the applanation state in spite of the rise in pressure caused by the inertia. For this reason, unfavorably, the peak of the reflected light quantity cannot be detected and the measurement of the intraocular pressure cannot be carried out accurately.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a noncontact type tonometer capable of accurately measuring the intraocular pressure of a subject's eye even if the intraocular pressure is much higher than normal.
To achieve the object, the noncontact type tonometer according to one aspect of the present invention comprises a fluid discharging means for discharging fluid toward a cornea of the eye, a pressure detecting means for detecting discharge pressure of the fluid, a corneal transfiguration detecting means for detecting the transfiguration of the cornea, and a discharge stopping means for determining the precise moment for stopping the operation of the fluid discharging means according to the discharge pressure detected by the pressure detecting means.
The noncontact type tonometer according to another aspect of the present invention comprises a fluid discharging means for discharging fluid toward the cornea of the eye, a corneal transfiguration detecting means for detecting the transfiguration of the cornea, a timer for counting elapsed time, and a discharge stopping means for determining the precise moment for stopping the operation of the fluid discharging means according to the elapsed time counted by the timer.
According to the present invention, the stopping of the operation of the fluid discharging means can be changed according to the intraocular pressure of the eye and therefore measurement proper to the intraocular pressure can be carried out.
That is, according to the present invention, it is avoidable that the measurement of the intraocular pressure cannot be carried out when the intraocular pressure is high and, to the contrary, fluid is discharged by unnecessary high pressure when the intraocular pressure is low. In the two cases, the intraocular pressure measurement can be carried out such that the fluid is discharged by proper pressure corresponding to the intraocular pressure of the eye.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing a first embodiment of a noncontact type tonometer according to the present invention.
FIG. 2 is a graph showing a measurement result of the instrument shown in FIG. 1.
FIG. 3(a) is a graph showing a measurement result of the tonometer of the first embodiment obtained when intraocular pressure is low.
FIG. 3(b) is a graph showing a measurement result of the tonometer of the first embodiment obtained when intraocular pressure is normal.
FIG. 3(c) is a graph showing a measurement result of the tonometer of the first embodiment obtained when intraocular pressure is high.
FIG. 4 is a graph showing a measurement result obtained when delay time Ta in FIG. 3(a) is applied to a subject's eye in FIG. 3(c).
FIG. 5 is a block diagram showing a second embodiment of the noncontact type tonometer according to the present invention.
FIG. 6 is a graph showing a measurement result of the instrument shown in FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a block diagram showing a measuring portion and a gas discharging device of a noncontact type tonometer according to a first embodiment of the present invention.
The instrument in FIG. 1 comprises a light source 1 for illuminating a subject's eye E with detecting light, a corneal transfiguration detecting portion 2 for receiving reflected light from the eye E to detect a transfiguration state of a cornea C in terms of a change of light in quantity, and a fluid discharging device 10 for discharging fluid (air in this embodiment) toward the eye E to transfigure the cornea C of the eye E.
The fluid discharging device 10 comprises a cylinder 11, a nozzle 12 mounted in the cylinder 11 and facing the eye E, a piston 13 for pushing out air within the cylinder 11 from the nozzle 12, a rotary solenoid 14 as a driving means for driving the piston 13, and a pressure sensor 15 mounted in the cylinder 11 for measuring pressure therein.
A corneal transfiguration signal output by the corneal transfiguration detecting portion 2 is compared with a reference signal output by a reference level generating circuit 4 by means of a comparator 3 and is input into a central processing unit (hereinafter simply referred to as "CPU") 20. When the level of the corneal transfiguration signal coincides with that of the reference signal, the comparator 3 outputs a coincidence signal to a stopping delay circuit 5. The level of the reference signal is equal to that of the corneal transfiguration signal obtained when the cornea C is transfigured into a predetermined state before an applanation state (a flat state), in other words, the coincidence signal is output when the cornea C reaches the predetermined state before the applanation state.
On the other hand, a pressure detecting signal output by an air pressure detecting portion 6 which receives a signal from the pressure sensor 15 is input to the stopping delay circuit 5 and the CPU 20. The stopping delay circuit 5 functions as a fluid discharging stopping means for stopping discharging fluid. That is, the stopping delay circuit 5, based on a level P of a pressure detecting signal obtained when a coincidence signal from the comparator 3 is input thereinto, determines delay time T according to the formula T=P×constant (F) and outputs a stopping signal to a solenoid driver 16 when the delay time T elapses from a point of time when the coincidence signal is input.
The higher the intraocular pressure of the cornea C of the eye E, the higher the level of the pressure detecting signal obtained when the coincidence signal is generated. Further, since the discharge pressure increases with time, the length of the delay time corresponds to an increased quantity of the discharge pressure obtained after the coincidence signal is generated. Accordingly, by determining the delay time in proportion to the discharge pressure obtained when the coincidence signal is generated, the maximum of the discharge pressure can be made high when the intraocular pressure is high and can be made low when the intraocular pressure is low. That is, the proper maximum of the discharge pressure corresponding to the intraocular pressure can be determined.
After alignment of the instrument shown in FIG. 1 with respect to the eye E is completed or the CPU 20 receives a measurement starting signal from a measuring switch (not shown), the CPU 20 outputs a driving signal to the solenoid driver 16 to apply an electric current to the rotary solenoid 14, so that air within the cylinder 11 is compressed by the piston 13 and is discharged from the nozzle 12 toward the eye E.
When the compressed air is discharged toward the eye E, the cornea C of the eye E is transfigured. As shown in FIG. 2, as the discharge pressure increases and the cornea approaches the applanation state, the corneal transfiguration signal output by the corneal transfiguration detecting portion 2 also gradually increases.
When the corneal transfiguration reaches the predetermined state before the applanation state and the corneal transfiguration signal exceeds a predetermined level B, the coincidence signal is output by the comparator 3 at the time point t1. The stopping delay circuit 5 determines the delay time T based on pressure P0 obtained when the coincidence signal is input and then the circuit 5 outputs a stopping signal to the solenoid driver 16 at the time point t2 at which the delay time T elapses. The solenoid driver 16 cuts the electric current sent to the rotary solenoid 14 when the stopping signal is input thereinto. Still, the discharge pressure continuously increases by inertia of the piston for a given period of time and then decreases.
Based on a pressure detecting signal P1 obtained when the corneal transfiguration signal reaches its peak, the CPU 20 calculates the intraocular pressure of the eye E by a predetermined conversion formula.
FIGS. 3(a) to 3(c) show examples of pressure signals and corneal transfiguration signals obtained when different intraocular pressures of the subject's eye are measured by the instrument of the above embodiment. FIG. 3(a) shows a case where the intraocular pressure is low, FIG. 3(b) shows a case where the intraocular pressure is normal, and FIG. 3(c) shows a case where the intraocular pressure is high.
The higher the intraocular pressure, the slower will be the change of the corneal transfiguration signal. Therefore the, time points ta, tb, tc at which a coincidence signal is each generated become gradually later, and in addition, respective values of pressure signals Pa, Pb, Pc corresponding to the time points become higher, and further, a period of time during which the cornea C is completely transfigured into an applanation state (a flat state) becomes longer. Accordingly, the delay time of each example, proportional to the values of the pressure signals Pa, Pb, Pc, is Ta<Tb<Tc.
FIG. 4 is a graph showing a case where the delay time Ta in FIG. 3(a) is applied, for comparison, to the eye E in FIG. 3(c). In this case, since the discharge pressure cannot rise to a high enough value to measure the intraocular pressure and decreases before the corneal transfiguration signal reaches its peak, the intraocular pressure measurement cannot be carried out.
FIG. 5 is a block diagram showing a second embodiment of the noncontact type tonometer according to the present invention. The instrument shown in FIG. 5 includes the constitution shown in FIG. 1 and, in addition, includes a time counting circuit 17 for counting elapsed time after an electric current begins to be applied to the rotary solenoid 14. However, an output from the pressure detecting portion 6 is input to the CPU 20 only and is not input to the stopping delay circuit 5.
Since the elapsed time has a linear relationship to the rise in pressure, the intraocular pressure of the eye E also corresponds to the elapsed time. Based on the elapsed time, the instrument of the second embodiment determines delay time ranging from a point of time when the cornea C is transfigured into a predetermined state to a point of time when the fluid discharging device 10 is stopped. That is, as shown in FIG. 6, on the supposition that TO is an elapsed time from the output of an coincidence signal, delay time T can be calculated by the formula T=TO×constant(F). The stopping delay circuit 5 outputs a stopping signal at the time point t2 at which the delay time T is over. The starting point of the delay time T is t1 at which an coincidence signal is output.
In the above embodiments, reference levels set in the reference level generating circuit 4 may be changed according to, for example, a first measurement result. Further, preferably, the constant(F) for calculating the delay time is changed. Further, these reference levels and constant(F) may be automatically changed by the CPU 20. | A noncontact type tonometer capable of accurately measuring intraocular pressure of a subject's eye even if the intraocular pressure is much higher than normal. The noncontact type tonometer comprises a fluid discharging device for discharging fluid toward a cornea of the eye, a corneal transfiguration detecting portion for detecting the corneal transfiguration, a pressure detecting portion for detecting discharge pressure of the fluid, and a delay circuit for determining the precise moment for stopping the operation of the fluid discharging means according to the discharge pressure detected by the pressure detecting means. | 0 |
This application is a continuation-in-part of application Ser. No. 08/718,925, filed Sep. 25, 1996.
FIELD OF THE INVENTION
The present invention relates to controlling the ride of a work vehicle such as a wheeled loader or tractor including a backhoe, bucket or implement. In particular, the present invention relates to controlling the action of the backhoe, bucket or other implement to improve the ride of the associated off-road or construction vehicle.
BACKGROUND OF THE INVENTION
Various types of off-road or construction vehicles are used to perform excavation functions such as leveling, digging, material handling, trenching, plowing, etc. These operations are typically accomplished with the use of a hydraulically operated bucket, backhoe or other implement. These implements include a plurality of linkages translationally supported and rotationally supported, and are moved relative to the supports by hydraulic cylinders or motors. As a result of the type of work excavators are used to perform (i.e. job site excavation) these excavators are often required to travel on roads between job sites. Accordingly, it is important that the vehicle travel at reasonably high speeds. However, due to the suspension, or lack thereof, and implements supported on the vehicle, vehicle bouncing, pitching or oscillation occurs at speeds satisfactory for road travel.
In an attempt to improve roadability, various systems have been developed for interacting with the implements and their associated linkages and hydraulics to control bouncing and oscillation of excavation vehicles while operating at road speeds. One such system includes circuitry for lifting and tilting an implement combined with a shock absorbing mechanism. This system permits relative movement between the implement and the vehicle to reduce pitching of the vehicle during road travel. To inhibit inadvertent vertical displacement of the implement, the shock absorbing mechanism is responsive to lifting action of the implement. The shock absorbing mechanism is responsive to hydraulic conditions indicative of imminent tilting movement of the implement thereby eliminating inadvertent vertical displacement of the implement.
Other systems for improving the performance of excavators have included accumulators which are connected and disconnected to the hydraulic system depending upon the speed of the vehicle. More specifically, the accumulators are connected to the hydraulic system when the excavator is at speeds indicative of a driving speed and disconnected at speeds indicative of a loading or dumping speed.
These systems may have provided improvements in roadability, but it would be desirable to provide an improved system for using the implements of excavation vehicles to improve roadability. Accordingly, the present invention provides a control system which controls the pressure in the lift cylinders of the implement(s) associated with an excavation vehicle based upon the acceleration of the vehicle.
SUMMARY OF THE INVENTION
An embodiment of the present invention provides a control system for an excavator of the type including an implement moveable relative to the excavator. The system includes a hydraulic fluid source, a hydraulic actuator, and an electronic valve coupled to the source and the actuator to control the flow of hydraulic fluid applied to the actuator by the source. A pressure transducer is provided to generate a pressure signal related to the pressure in the actuator. The system also includes an electronic controller coupled to the electronic valve and the pressure transducer. The controller determines the acceleration of the excavator based upon the pressure signal, and applies control signals to the electronic valve to cause the electronic valve to control the flow of hydraulic fluid applied to the actuator to maintain the pressure signal substantially constant.
An alternative embodiment of the control system includes an accelerometer instead of the pressure transducer. The accelerometer is coupled to the excavator to generate an acceleration signal representative of the acceleration of the excavator. The controller determines the acceleration of the excavator based upon the acceleration signal, and applies control signals to the electronic valve to cause the electronic valve to control the flow of hydraulic fluid applied to the actuator to maintain the acceleration signal substantially constant at a value of zero.
The present invention also relates to an excavator including a wheeled vehicle, an implement movably supported by the vehicle, a hydraulic fluid source supported by the vehicle, and a hydraulic actuator coupled between the implement and vehicle to move the implement relative to the vehicle. An electronic valve is coupled to the source and the actuator to control the flow of hydraulic fluid applied to the actuator by the source. The excavator also includes means for generating an acceleration signal representative of the acceleration of the vehicle, and an electronic controller coupled to the electronic valve and the accelerometer. The controller determines the acceleration of the excavator based upon the acceleration signal, and applies control signals to the electronic valve to cause the electronic valve to control the flow of hydraulic fluid applied to the actuator to maintain the pressure signal substantially constant based upon the acceleration signal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic side elevation view of a wheel loader equipped with a bucket or other suitable implement shown in various elevational and tilted positions.
FIG. 2 is a diagrammatic view of a hydraulic actuator system used with the wheel loader illustrated in FIG. 1 and including an electronic controller according to the present invention.
FIG. 3 is a schematic block diagram of the ride control system forming part of the present invention.
FIG. 4 is a schematic block diagram of the electronic controller forming part of the present invention.
FIG. 5 is a diagrammatic view of a control system used with the wheel loader illustrated in FIG. 1 and including an accelerometer in a second embodiment of the present invention.
FIG. 6 is a schematic block diagram of a second embodiment of the ride control system forming part of the present invention.
FIG. 7 is a schematic block diagram of a second embodiment of the electronic controller forming part of the present invention.
FIG. 8 is a block diagram of a proportional integral (PI) control unit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, a wheel loader 10, which is illustrative of the type of off-road construction vehicle in which the present control system can be employed, is shown. Wheel loader 10 includes a frame 12; air filled tires 14 and 16; an operator cab 18; a payload bucket 20 or other suitable implement; a pair of lift arms 22; a pair of hydraulic actuators 24; hydraulic actuator columns 23; and hydraulic actuator cylinders 25.
Frame 12 of wheel loader 10 rides atop tires 14 and 16. Frame 12 carries the operator cab 18 atop the frame. A pair of lift arms 22 are connected to frame 12 via a pair of arm pivots 26. The lift arms are also connected to the frame by hydraulic actuators 24 which are made up of actuator columns 23 which translate relative to actuator cylinders 25. Payload bucket 20 is pivotally connected to the end of lift arms 22.
Wheel loader 10 includes a hydraulic system 50 coupled to actuators 24 to raise, lower, or hold bucket 20 relative to frame 12 to carry out construction tasks such as moving and unloading the contents thereof. More specifically, hydraulic actuators 24 control movement of the lift arms 22 for moving bucket 20 relative to frame 12. (Bucket 20 may be rotated by a hydraulic actuator which could be controlled by system 50.) Actuator columns 23 extend relative to actuator cylinders 25 forcing lift arms 22 to pivot about arm pivots 26 causing bucket 20 to be raised or lowered, as shown by phantom lines in FIG. 1.
Referring to FIG. 2, the hydraulic system 50 also includes a hydraulic fluid source 30; a hydraulic return line 32; a hydraulic supply conduit 34; a hydraulic pump 36; hydraulic lines 38, 42, and 44; an electronic valve 40; and a pressure transducer 46. Hydraulic system 50 also includes a position sensor 48; an analog-to-digital converter (ADC) 52; a position signal data bus 54; a pressure signal data bus 56; an electronic controller 58; a control signal data bus 60; a digital to analog converter 62; and an analog control signal conductor 64. By way of example, valve 40 may be a Danfoss electrohydraulic valve with spool position feedback.
Hydraulic fluid source 30 is connected to pump 36 via hydraulic supply conduit 34, pump 36 is connected to electronic valve 40 via line 38, electronic valve 40 is connected to hydraulic actuator 24 via lines 42 and 44, and pressure sensor 46 is also in fluid communication with line 42. Hydraulic actuator 24 is also connected to electronic valve 40 via line 44. Electronic valve 40 is further connected to hydraulic source 30 via hydraulic return line 32 thereby completing the hydraulic circuit of hydraulic system 50. Pressure transducer 46 and position sensor 48 are connected to ADC 52. Electronic controller 58 is connected to ADC 52 via position signal data bus 54 and pressure signal data bus 56, connected to DAC 62 via control signal data bus 60, which is connected to valve 40 via analog control signal bus 64.
Electronic controller 58 operates to keep the pressure in hydraulic actuators 24 relatively constant thereby dampening vertical motions of the vehicle. In operation, pressure transducer 46, which is in fluid communication with the hydraulic fluid, measures the pressure in hydraulic line 42 which is substantially the same as that in hydraulic actuator 24. A signal from pressure transducer 46 is communicated to ADC 52 where the analog sensor signal is converted to a digital signal. Position sensor 48 measures the angular position of the lift arms 22. The analog position sensor signal is also sent to the ADC where it is converted to a digital signal. The sampled position signal and the sampled pressure signal are communicated to electronic controller 58 over data buses 54 and 56 respectively. Using the sampled sensor information electronic controller 58 calculates a digital control signal. The digital control signal is passed over data bus 60 to DAC 62 where the digital signal is converted to an analog control signal that is transmitted over connection 64 to electronic valve 40.
By way of example, controller 58 could be a digital processing circuit such as an Intel 87C196CA coupled to a 12 bit ADC. Furthermore, DAC 62 typically would include appropriate amplification and isolation circuits to protect the associated DAC and control valve 40. Alternatively, DAC 62 could be eliminated by programming controller 58 to generate a pulse-width-modulated (PWM) signal. Valve 40 would in turn be a PWM valve controllable with a PWM signal.
Electronic valve 40 controls the flow of hydraulic fluid into and out of hydraulic actuator 24 thereby causing actuator column 23 to move in or out of actuator cylinder 25. Hydraulic fluid is supplied to electronic valve 40. The fluid originates from hydraulic fluid source 30, through supply conduit 34, to pump 36 which forces the hydraulic fluid through line 38 and into electronic valve 40. Electronic valve 40 controls the ingress and egress of hydraulic fluid to hydraulic actuator 24. Electronic valve 40 controls both the path of flow for the hydraulic fluid and the volumetric flow of hydraulic fluid. Electronic valve 40 directs hydraulic fluid either into line 42 and out of line 44 or into line 44 and out of line 42 depending on the intended direction of travel of actuator 24. The analog control signal received from bus 64 commands electronic valve 40 to control both the direction of hydraulic fluid flow and the volumetric flow of the fluid. By way of example, both the fluid direction signal and the flow volume signal can be generated by DAC 62. However, the flow direction signal may be generated at a digital I/O 65 of controller 58, and if a PWM valve is used, the PWM signal applied to the valve can also be generated at a digital I/O. Excess hydraulic fluid is directed by electronic valve 40 through return line 32 and back to hydraulic fluid source 30.
Referring to FIG. 3, electronic controller 58 includes a setpoint calculator 70; a pressure regulator 74; a nonlinear converter 78; a pressure set point signal bus 72; and an ideal pressure control signal bus 76.
The input side of electronic controller 58 is connected to data buses 54 and 56. Data buses 54 and 56 are connected to set point calculator 70. Pressure regulator 74 is connected to data bus 56 and set point calculator 70 via pressure set point signal connection 72. Ideal pressure control signal connection 76 connects pressure regulator 74 to nonlinear converter 78. Nonlinear converter 78 connects the output side of electronic controller 58 to data bus 60.
Setpoint calculator 70 calculates the pressure setpoint used by electronic controller 58 to maintain the hydraulic fluid pressure in actuator 24 relatively constant. To calculate the proper pressure setpoint, information from both pressure transducer 46 and position sensor 48 is communicated to pressure setpoint calculator over data bus 56 and 54 respectively. The output of setpoint calculator 70 is a pressure setpoint signal passed over bus 72 to pressure regulator 74. Pressure regulator 74 uses information from pressure set point calculator 70 and from pressure transducer 46 passed over data bus 56 to calculate an ideal pressure control signal. The ideal pressure control signal is passed over bus 76 to nonlinear converter 78. Nonlinear converter 78 outputs a sampled control signal over data bus 60.
Referring to FIG. 4, setpoint calculator 70 includes amplifiers 80, 92, and 94; a voltage to displacement converter 82; a position setpoint memory 86; a differencing junction 88; a deadzone nonlinearity circuit 90; a single pole low-pass filter 98; a summing junction 102; a position error signal bus 89; and signal buses 84, 93, 96, and 100. Pressure regulator 74 includes a differencing junction 104; a state estimation circuit 108; a derivative gain circuit 112; a proportional gain circuit 116; a summing junction 120; an error signal bus 106; a time rate of change of pressure error signal connection 110; and signal connections 114 and 118. Nonlinear converter 78 includes a pressure signal bias memory 122; a summing junction 124; a coulombic friction circuit 128; a saturation circuit 132; an amplifier 136; and signal buses 126, 130, and 134.
Data bus 54 and 56 are connected to the input side of setpoint calculator 70. Data bus 54 is connected to gain 80. The output of amplifier 80 is connected to converter 82. The output of converter 82 and memory 86 are connected to differencing junction 88.
Setpoint calculator 70 receives a signal from position signal data bus 54. This signal is amplified by amplifier 80 to generate a signal applied to converter 82 which seals the signal to correspond (e.g. proportional to) to displacement of lift arms 22. The sealed signal is compared with position setpoint selected with memory 86 at differencing junction 88 to generate an error signal. The error signal is communicated to deadzone nonlinearity 90 which provides a zero output when the position of the lift arms 22 are within a predetermined range of the setpoint (e.g. two degrees). Thus, deadzone nonlinearity 90 ensures that the position control does not interfere with small motions created by the pressure control. The signal output by deadzone nonlinearity circuit 90 is amplified by amplifier 92, set at 0.02 in the present embodiment. Amplifier 92 modifies the signal to correspond to actuator pressure when applied to summing junction 102 as discussed in further detail below.
Setpoint calculator 70 also receives a sampled pressure signal from data bus 56. The sampled pressure signal is multiplied by amplifier 94. This signal is communicated via bus 96 to single pole low-pass filter 98 which has a cut-off frequency at 0.1 Hz in the present embodiment. The signals from low-pass filter 98 and amplifier 92 are passed via buses 100 and 93, respectively, to summing junction 102 where they are added to produce a pressure setpoint signal and are applied to pressure regulator 74.
Pressure signal data bus 54 and pressure setpoint signal bus 72 are connected to the input side of pressure regulator 74. Buses 54 and 72 are connected to summing junction 104. The output connection 106 of summing junction 104 is split, and coupled with state estimator 108 and proportional gain-circuit 116. Bus 110 of state estimation circuit 108 is connected to derivative gain amplifier 112. Bus 114 of amplifier 112 and bus 118 of proportional gain amplifier 116 are connected to summing junction 120 which is connected to ideal pressure control signal bus 76.
Pressure regulator 74 receives the sampled pressure signal over data bus 56 and the calculated pressure setpoint signal over bus 72. The two signals are compared using differencing junction 104 which produces a pressure error signal that is applied to proportional gain amplifier 116 and state estimation circuit 108. State estimator 108 calculates an estimate of the time rate of change of the pressure error signal. This signal is applied to derivative gain amplifier 112 (e.g. amplification of 5 to 1), which multiplies the signal and applies it to summing junction 120. Proportional gain amplifier 116 (e.g. amplification of 40 to 1) multiplies the signal and applies the multiplied signal to summing junction 120. The signals communicated over buses 118 and 114 to junction 120 are both added by summing junction 120 to yield the ideal pressure control signal which is applied to nonlinear converter 78 via bus 76.
Pressure control signal bus 76 is connected to the input side of nonlinear conversion circuit 78. Bus 76 and offset memory 122 are both connected to summing junction 124. Output bus 126 of summing junction 124 is connected to coulombic friction element 128, and coulombic friction element 128 is connected to saturation element 132. Output connection 134 couples saturation element 132 to amplifier 136 which is connected to control signal data bus 60.
The purpose of nonlinear conversion circuit 78 is to transform the ideal pressure control signal to a valve command signal which takes into account nonlinear effects of valve 40 including frictional losses and saturation in which the valve has some maximum hydraulic fluid flow rate. Circuit 78 adds the ideal pressure control signal to the value set by circuit 122 at summing junction 124. The purpose of the bias is to make a no-flow command correspond to the center position of the valve. Summing junction 124 communicates a signal over bus 126 to coulombic friction circuit 128. Coulombic friction circuit 128 compensates for the deadband of electronic valve 40, and modifies the signal based upon the deadband. Circuit 128 adds a positive offset to positive signals and adds a negative offset to negative signals. Coulombic friction circuit 128 communicates a signal over connection 130 to saturation element 132. Saturation element 132 models the maximum and minimum flow limitations of electronic valve 40 and clips the signal if it corresponds to flow values outside of the maximum or minimum flow values of the valve. Saturation element 134 communicates a signal over connection 136 to amplifier 136 which generates the sampled valve command which is communicated over control signal data bus 60. In the preferred embodiment circuits 70, 74 and 78 are implemented with a programmed digital processor. Thus, prior to amplification by amplifier 136, the flow control signal would be applied to DAC 62.
Low-pass filter 98 is not limited to a filter with cut-off frequency of 0.1 Hz but only requires a filter with cut-off frequency that is substantially below the natural resonant frequency of the vehicle/tire system. The low-pass filter 98 is also not limited to being a single pole filter, but may be a filter having multiple poles. The gain values and offset constants are not limited to the values described above but may be set to any values that will achieve the goal of keeping the hydraulic actuator pressure substantially constant while keeping the implement in a generally fixed position. The ride control system is further not limited to having both a position sensor 48 as well as a pressure transducer 46, but may function without the position sensor. The position sensor aids in limiting the implement to relatively small displacements. If the ride control system is to include position sensor 48, it may be but is not limited to be a rotary potentiometer, which measures angular position of the lift arms, or a linear voltage displacement transducer (LVDT), which measures the extension or distension of actuator shaft 23.
The sensor used to generate the acceleration signal is not limited to the pressure transducer 46 but an accelerometer or other sensor for directly sensing acceleration may be used. In an alternate embodiment, as illustrated in FIG. 5, the pressure signal generated by transducer 46 can be replaced or supplemented with an acceleration signal generated by an accelerometer 138. Referring to FIG. 5, the hydraulic system 50 includes a hydraulic fluid source 30; a hydraulic return line 32; a hydraulic supply conduit 34; a hydraulic pump 36; hydraulic lines 38, 42, and 44; and an electronic valve 40.
The control system also includes an accelerometer 138; a position sensor 48; an analog-to-digital converter (ADC) 52; a position signal data bus 54; an acceleration signal data bus 140; an electronic controller 58; a control signal data bus 60; a digital to analog converter 62; conductor 141; amplifier 142; and an analog control signal conductor 64. Preferably, accelerometer 138 is configured to generate a signal representative of acceleration in a vertical direction, i.e., in a direction substantially perpendicular to the surface upon which the work vehicle rests. In this embodiment, the control system is configured to maintain acceleration substantially constant at zero.
Accelerometer 138 and position sensor 48 are connected to ADC 52. Electronic controller 58 is connected to ADC 52 via position signal data bus 54 and acceleration signal data bus 140, is connected to DAC 62 via control signal data bus 60. DAC 62 is connected to electronic valve 40 via conductor 141, amplifier 142, and analog control signal conductor 64.
Electronic controller 58 operates to keep the pressure in hydraulic actuators 24 relatively constant thereby dampening vertical motions of the vehicle. In operation, accelerometer 138, which may be located in the vehicle cab, measures the vertical acceleration of the vehicle. A signal from accelerometer 138 is communicated to ADC 52 where the analog acceleration signal is converted to a digital acceleration signal. Position sensor 48 measures the angular position of the lift arms 22. The analog position sensor signal is also sent to the ADC 52 where it is converted to a digital position signal. The sampled position signal and the sampled acceleration signal are communicated to electronic controller 58 over data buses 54 and 140 respectively. Using the sampled sensor information, electronic controller 58 calculates a digital control signal. The digital control signal is passed over data bus 60 to DAC 62 where the digital signal is converted to an analog control signal that is amplified by amplifier 142. The amplified control signal is transmitted over conductor 64 to electronic valve 40.
Electronic valve 40 controls the flow of hydraulic fluid into and out of hydraulic actuator 24 thereby causing actuator column 23 to move in or out of actuator cylinder 25. The analog control signal received from bus 64 commands electronic valve 40 to control both the direction of hydraulic fluid flow and the volumetric flow of the fluid. By way of example, both the fluid direction signal and the flow volume signal can be generated by DAC 62. Excess hydraulic fluid is directed by electronic valve 40 through return line 32 and back to hydraulic fluid source 30.
A second embodiment of the electronic controller is illustrated in FIG. 6. Referring to FIG. 6, electronic controller 58 includes signal buses 144 and 146; an acceleration controller 148; a position controller 150; and a nonlinear converter 152.
The input side of electronic controller 58 is connected to data buses 54 and 140. The acceleration controller 148 is connected via acceleration control signal bus 144 to the nonlinear converter 152. The position controller 150 is connected via position control signal bus 146 to the nonlinear converter 152. The output of the nonlinear converter is connected to data bus 60.
Referring to FIG. 7, acceleration controller 148 calculates the acceleration control signal used by electronic controller 58 to maintain the hydraulic fluid pressure in actuator 24 relatively constant. More specifically, acceleration controller 148 includes a filter 154, an integrator 156; a velocity setpoint memory 158; a differencing junction 160; and an acceleration PI (proportional-integral) control unit 162. The output of the acceleration controller 148 is a signal passed over the acceleration control signal bus 144 to the nonlinear converter 152.
To calculate the proper acceleration control signal, information from the accelerometer 138 is communicated to the acceleration controller 148 over data bus 140. The signal on bus 140 is amplified by amplifier 164 to generate a signal applied to the filter 154. The filter 154 is a median filter designed to remove spike noise from the acceleration signal. The output of the filter 154 is fed to an integrator 156, which generates a velocity signal representative of vertical velocity. The velocity signal is compared with a velocity setpoint selected from memory 158 at the differencing junction 160 to generate an error signal on bus 166. Preferably, the velocity setpoint, representative of desired vertical velocity, is set to zero. The error signal is communicated to the acceleration control PI unit 162. The acceleration control PI unit 162 computes an acceleration control signal by applying a proportional integral control algorithm to the error signal. The acceleration control signal is communicated over the acceleration control signal bus 144 to the nonlinear converter 152.
A PI unit is shown in more detail in FIG. 8. Essentially, an input signal is directed along two paths. In one path, the input signal is amplified by a gain circuit 208 to produce a signal on bus 210. In the other path, the input signal is integrated with respect to time by circuit 212, and amplified by a gain circuit 214 to produce a signal on bus 216. A summing junction 218 adds the signals on buses 210 and 216 to produce the output control signal on bus 220.
The position controller 150 also calculates a position control signal used by the nonlinear converter 152. The position controller 150 essentially acts to eliminate any slow upward or downward movement of the implement over time. The position controller 150 is placed in parallel to the acceleration controller 148. The position controller 150 includes a voltage to displacement converter 168; a position setpoint memory 170; a differencing junction 172; a deadzone nonlinearity circuit 174; a position PI (proportional integral) control unit 176; a low pass filter 178; and signal buses 180, 182, 184, 186, 188. The output of the position controller 150 is a signal passed over the position control signal bus 146 to the nonlinear converter 152.
More specifically, information from the position sensor 48 is communicated to the position controller 150 over data bus 54. The signal on bus 54 is amplified by an amplifier 190 to generate a signal applied to the converter 168. The converter 168 scales the signal to correspond to the displacement of lift arms 22. The scaled signal is compared with position setpoint selected with memory 170 at differencing junction 172 to generate an error signal on bus 184. The error signal is communicated to deadzone nonlinearity circuit 174 which provides a zero output when the position of the lift arms 22 are within a predetermined range of the setpoint (e.g. two degrees). Thus, deadzone nonlinearity circuit 174 ensures that the position control does not interfere with small motions created by the acceleration control. The signal output of deadzone nonlinearity circuit 174 is sent to position PI control unit 176. The position PI control unit 176 computes a control signal by applying a proportional integral control algorithm to its input signal as illustrated in FIG. 8. The output signal from the control unit is sent to the low pass filter 178. The output signal of the filter 178 is sent via signal bus 146 to the nonlinear converter 152.
As mentioned, the acceleration control signal bus 144 is connected to the input side of nonlinear converter 152, as is the position control signal bus 146. Nonlinear converter 152 includes a summing junction 194; a coulombic friction circuit 196; a saturation circuit 198; and signal buses 204 and 206. The output bus 204 of summing junction 194 is connected to the coulombic friction circuit 196. The output of the coulombic friction circuit 196 is connected to the saturation circuit 198 via bus 206. The output of the saturation circuit 198 is a signal on control signal data bus 60.
The purpose of the nonlinear converter 152 is to transform the valve control signal on bus 204 to a signal which takes into account nonlinear effects of valve 40 including frictional losses and saturation in which the valve has some maximum hydraulic fluid flow rate. The acceleration control signal and the position control signal are added together at summing junction 194. Summing junction 194 communicates a signal to the coulombic friction circuit 196. Coulombic friction circuit 196 compensates for the deadband of electronic valve 40, and modifies the signal based upon the deadband. Circuit 196 adds a positive offset to positive signals and adds a negative offset to negative signals. Coulombic friction circuit 196 communicates a signal over connection 206 to saturation circuit 198. Saturation circuit 198 models the maximum and minimum flow limitations of electronic valve 40 and clips the signal if it corresponds to flow values outside of the maximum or minimum flow values of the valve. Saturation circuit 198 communicates a signal over data bus 60. In the preferred embodiment, controllers 148 and 150, and nonlinear converter 152 are implemented with a programmed digital processor. Thus, prior to amplification by amplifier 142, the flow control signal would be applied to DAC 62, as is illustrated in FIG. 5.
The control system as described in FIGS. 6 and 7 does not require both the acceleration controller 148 and position controller 150, but is operable using the acceleration controller by itself.
The type of work vehicles and excavators to which the described ride control can be applied includes, but is not limited to, backhoes, snowplows, cranes, skid-steer loaders, tractors including implements such as plows for earth working, wheel loaders (see FIG. 1), and other construction or utility vehicles having an implement, arm, or boom moveable relative to the vehicle frame. The ride control system is not limited to vehicles with a pair of lift arms 22 such as the wheel loader 10, but may also be applied to vehicles with a multiplicity of lift arms or a single lift arm such as on a backhoe or a crane.
The actuation devices, used to move the implements, are used to dampen bouncing and pitching of the vehicle by appropriately moving the implement relative to the vehicle frame. The ride control system may be applied to vehicles using various types of hydraulic actuation systems including hydraulic actuators 24 and hydraulic motors.
The electronic controller 58 shown in FIGS. 2 and 5 are programmed microprocessors but can also be other electronic circuitry, including analog circuitry, that provides the proper control signal to the electronic valve 40 to keep the pressure in the hydraulic actuator 24 substantially constant. The programming of the microprocessors is not limited to the methods described above. An appropriate control scheme can be used such that the goal is to keep the hydraulic cylinder pressure constant. Such control techniques include but are not limited to classical control, optimal control, fuzzy logic control, state feedback control, trained neural network control, adaptive control, robust control, stochastic control, proportional-derivative (PD) control, and proportional-integral-derivative control (PID).
From the foregoing, it will be observed that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present control system. It will be appreciated that the present disclosure is intended as an exemplification of the control system, and is not intended to limit the control system to the specific embodiment illustrated. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims. | A control system for improving the roadability of a wheeled excavator is disclosed herein. The excavator is the type including an implement such as a bucket or backhoe which is moved relative to the excavator by hydraulic actuators. Hydraulic fluid is applied to the actuators via electronic valves which are controlled by an electronic controller. Based upon acceleration of the vehicle, the electronic controller controls the electronic valve to maintain fluid pressure in the actuator or the acceleration substantially constant. Additionally, the controller can be configured to maintain the average position of the implement generally constant. By controlling the pressure in the hydraulic actuator, the undesirable bouncing or pitching of the excavator can be reduced when the vehicle is traveling at road or loading speeds. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to devices for teaching hairstyling and the like, and more particularly to a mannequin head having hair thereon and which is marked with various indicia to guide a student in learning hairstyling.
2. Description of the Prior Art
In beauty schools in which hairstyling and cutting is taught, it is common for the instructor to demonstrate on mannequin heads or on human models, and thereafter to require the students to attempt to duplicate the demonstrated techniques. It is also common to utilize two dimensional charts and photographs as well as written descriptions to guide the student in learning specific hairdressing skills. However, the effectiveness of these prior art techniques is limited requiring much trial and error on the part of the student to become proficient.
It is clear that some form of three dimensional teaching aid or devices would be more efficient and would minimize individual attention of the instructor. A step in this direction has been made by Trowbridge in U.S. Pat. No. 3,458,943 which teaches a model head covered with Velcro R material over the area normally covered by hair. Swatches of wig material made of or simulating human hair are provided that can be worked individually on a particular area of the head. While of some help in defining specific areas of the head, no help in direction or rolling, combing or cutting are indicated and fall short of an ideal teaching aid. U.S. Pat. No. 2,975,534 to Lutz comprises an inflatable balloon-like device which ca be blown up and attached to a base. The device may have certain instructional patterns for hairstyling indicated as if the device were a head. While perhaps superior to a flat or two dimensional chart, the device does not allow actual manipulation of the hair but only provides reference patterns.
SUMMARY OF THE INVENTION
My invention contemplates a mannequin head form having a natural size with artificial or human hair attached to the scalp portions and of proper length for practice of hairstyling. The device may take many forms: for example, a hollow head form may be used formed from plastic or the like. The hair is then stitched through the surface of the form in the manner that wigs and hairpieces are made. Prior to attaching of the hair, the scalp portion is marked off to define various areas and shapes, each of which is to indicate the portion of the head for a particular hairdressing technique. The marked off areas may also include additional markings indicating the direction to which the hair is to be combed or curled. Each of the marked off areas may be identified by numbers, letters, or other indicia. In using my teaching aid, the instructor would first demonstrate the particular hair treatment applicable to one of the marked off areas indicating how the markings indicate the direction of various operations, and thereafter, each student would reproduce the demonstrated work on his or her model head. With appropriate notes, or written instructions, a student may practice alone with my novel training mannequin head and will, of course, by guided by the markings and indicia which may be seen by combing out the hair attached to the particular areas.
In addition to indicating areas for specific treatment, other indicia may be applied; for example, locations of individual curls may be shown by dashed or solid line geometrical forms in the appropriate places on the head. Where finger waves or other hair treatments requiring the use of the fingers or implements, arrows may be placed appropriately to indicate the direction of working or of applying the fingers or implements. It is to be understood that a mannequin head will be designed and marked for a particular type of styling and that a number of such heads will be used to cover various styles. To reduce the cost of the teaching aid of my invention and to encourage keeping up to date with changing hairstyles, a version may be constructed using relatively thin rubber in the form of a cap which may then be installed on a permanent head form made from plastic, or similar materials.
It is therefore a principal object of the invention to provide a teaching aid in the form of a three dimensional model head with markings and indicia on the scalp portion thereof to provide a three dimensional instructional device for use by hairstyling instructors and students.
It is another object of the invention to provide a teaching aid for an instructor which is used to demonstrate hairstyling and hairdressing techniques to a student with referencce to various markings and indicia on the device.
It is yet another object of my invention to provide a mannequin head having hair attached thereto in which the scalp portion is marked off into appropriate areas in which a different hairdressing or styling technique may be applied to different areas.
It is still another object of my invention to provide a mannequin head for students learning the hairstyling and hairdressing art to be guided during practice by various markings and indicia on the scalp area of the model head.
It is a further object of my invention to provide a model head having hair attached to the scalp area thereof in which the scalp area is marked with arrows, patterns, and the like which may indicate the direction of applying the fingers or tools and the positions of curls or other decorative hair forms.
These and other objects and advantages will become apparent from the detailed description and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a typical head form of the invention showing the manner of attachment of hair thereto;
FIG. 2 is a view of a mannequin head form of the invention before attaching hair thereto and indicating typical pattern markings thereon;
FIG. 3 is a mannequin head form of the invention showing markings which may be used to indicate locations of standup curls and of arc curls;
FIG. 4 is a mannequin head form of the invention showing arrow markings which may indicate finger placement positions for producing finger wave-type styling;
FIG. 5 is a diagrammatic representation of a mannequin head form of the invention with the majority of the hair omitted showing a dot pattern array forming both horizontal and vertical line patterns useful for teaching steps for cutting, parting, bleaching and coloring of hair; and
FIG. 6 is an alternative form of the invention using a partial head form.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a cross-sectional view through a typical mannequin head form suitable for the invention is shown. A head form 10 may be formed from plastic or similar material having a wall thickness sufficient to provide a rigid form suitable for use by students in learning the hairdressing art. It is to be understood that the form 10 is shown for exemplary purposes only and many variations are equally well suited to my invention. Form 10 has a hollow neck portion 11 which may be mounted on a permanent stand or a weighted base when in use. Either human or artificial hair 12 is inserted through the walls of head form 10 and sewn or otherwise fastened to the interior surface. A few strands of hair 12 are shown attached to illustrate the attachment of hair; however, it is to be understood that the entire normal hair growing area of a female head is covered with hair as indicated by the dashed line 13.
Prior to attaching hair to a head form 10, in accordance with my invention, the scalp area may be marked off for various purposes. Turning to FIG. 2, a head form 10 is shown prior to attachment of hair thereto with markings appropriate for teaching of permanent waving. To this end, the scalp area is marked off in blocks 16 by bold lines 12 with each separate block identified by a number or other indicia. In this example, blocks 1 through 9 may be seen although a greater or lesser number of blocks may be utilized depending upon the types of hair styles to be taught. Although a few strands of hair 18 are shown for illustrative purposes, the remainder of the hair has been omitted to better show the blocking markings and indicia. Each block includes additional markings 14 which indicate certain directions of handling of the hair strands in such areas. Other types of markings are shown at 19 which shows a crescent marking indicating the direction of forming certain curls and a dashed line 21 indicating finger or implement placing directions. After attachment of the hair to head form 10, the markings and indicia are easily visible to the user as the hair is worked.
A mannequin head form 10, as in FIG. 2, is utilized by a hairdressing instructor to first demonstrate to a group of students how to block or section the hair for permanent waving. For example, the hair in block number 7 would be picked up with the fingers and clipped together in some manner to maintain it separate from the hair in an adjacent section such as block 8. The hair in each block is sectioned out and clipped. Thus, the student is shown how to separate the various areas of the hair by reference to markings 12 to isolate those areas for individual treatment. After blocking of the hair, the instructor may then illustrate the proper manner of applying the curling rods to the hair in each block. For example, in block 7, the rods would be applied to thin layers of hair along the dashed lines. Similarly, in block 6, rods would be applied to the thin layers of hair in the direction of dashed lines 14 so as to form a V pattern. As may be understood, each block includes dashed lines 14 indicating directions for application of rods but are omitted in FIG. 2 for clarity. Where curls are formed as indicated by marking 19, the fingers are placed along dashed line 21 to form the desired curl in the proper orientation.
After demonstrations by the instructor, the student may then easily repeat the action of the teacher by simply following the blocking lines 12 for each of the blocks 16 on his or her mannequin head form. The head form 10 thus provides a three dimensional guide and eliminates guess work and judgment as to proper blocking of the hair during the early stages of the students training. As may be recognized, the three dimensional form eliminates the necessity for a number of two dimensional drawings or illustrations which are often confusing to the new student.
Many other types of markings may be used as well as the blocking marks 12 discussed above. In FIG. 3, for example, mannequin head form 10 is shown with several special curl forming markings. It is to be understood that this illustration is not of an actual head form but is merely presented to illustrate such special markings which are commonly used with various hair styles. Thus, the types of markings shown may be used in appropriate areas in conjunction with other basic markings. A set of curl setting patterns is shown by the dashed line markings 20 for a series of straight curls 22. As may be noted, the size of a marking 20 will indicate the approximate length and thickness of the curl 22. Another type of curl which has a conical form is shown at 26 with the dashed line markings 24 indicating the approximate shape ad size of each curl and the location on the head form for such curls. Marking 25 indicates an S-shaped pattern for producing parallel curls 27. Dashed lines 29 indicate the direction for placing of the fingers in forming such curls.
Markings to indicate finger waving are shown in FIG. 4 on form 10. A number of curved arrows 30 are marked on the head form which show both the directions for placement of the fingers during curling and the direction of the crests of the curls 28.
Another useful mannequin head form marking is indicated in FIG. 5 which consists of an array of dots covering the hair area of form 10. As may be understood, except for strands of hair 35 and 36, the hair has been omitted in FIG. 5 for illustrative purposes. The head form of FIG. 5 is useful in training students in hair cutting procedures and parting techniques since the dots are arranged to form both vertical and horizonal rows. During cutting and parting of the hair, it is desirable to pick up between the fingers thin layers of hair strands in either a horizontal or a vertical orientation. For example, as shown generally at 33, hair strands 36 have been picked up in a horizontal pattern. As shown generally at 37, hair strands 35 have been picked up in a vertical pattern. Although it is unlikely that the head form of FIG. 5 would be used for actual cutting practice, it is beneficial for teaching of the techniques of isolating portions of the hair to be cut. This type of head form is also very useful in teaching parting patterns and in practicing the handling of hair strands in a uniform and controlled manner as is necessary for bleaching and coloring of hair.
Although the invention has been described above in terms of a head form 10, an alternative embodiment may utilize a skull cap type form. In FIG. 6, a skull cap 50, formed from thin rubber, plastic or the like is shown. Skull cap 50 may be installed onto a plain, smooth surface head form such as commonly available for wig stands, as millinery heads, and the like. The outer surface of cap 50 is marked off with any of the markings 54 as previously described and hair strands 52 are sewn or cemented into the cap 50 as shown at 52 and 53. While this alternative embodiment is illustrated as a skull cap 50, a full head and face type form of thin rubber which could be slipped over a solid head form is also practical.
It is contemplated that the teaching aid type head form of the invention would be produced in sets of forms with each form marked with markings adapted to teach a particular style, skill, or technique, and to provide means for self-teaching when an instructor is not available. While certain specific implementations of my invention have been disclosed herein, it will be obvious to those of skill in the art to make numerous changes or modifications thereof without departing from the spirit and scope of my invention. | A mannequin head form having human or artificial hair in which the hair bearing surfaces are marked to permit demonstration of hairdressing techniques by an instructor and to guide a student in learning and practicing such techniques. Respective ones of a group of head forms may have markings and indicia to show: areas for blocking for permanent waving; shapes and loctions of curls; direction of finger and tool placement for waving and the like; directions for partitioning the hair for cutting, parting, bleaching, and coloring; and other general or specialized instructional markings. The markings and indicia are visible to the user as the hair is manipulated. | 6 |
FIELD OF INVENTION
[0001] The present invention belongs to veterinary field and refers to development of drug sustained-release pharmaceutical excipients and forms, and more particularly is related to a composition which increases bioavailability and long-action sustained release (FOLA) of antibacterial drugs, analgesics, mucolytics, anticoccidial drugs, vitamins, minerals and other drugs in commercial poultry and pigs.
BACKGROUND OF INVENTION
[0002] In spite of poultry farming high technology level, the use of antimicrobials in the main countries in our continent is far from being the best suitable, and several mistakes in pharmaceutical design of antibiotics, anticoccidial drugs and other drugs for application in poultry have been documented. That above is in fact a significant problem for public health when considering that an unsuitable use of antimicrobials in birds is a potential cause of bacterial resistance leading to a clinical response decrease both in animals and humans by pathogens such as Escherichia coli, Salmonella sp and Campylobacter sp. (Pigan & Kolter, 2002, Lenski, 1998).
[0003] Serum profiles of an antimicrobial or antimicrobial activity profile of a drug and its metabolites during a certain time define the way in which an antimicrobial optimally acts in what is called pharmacokinetics/pharmacodynamics ratio or rationality (PK/PD) in antibacterial activity. For example: there is little or null rationality between “antibacterial destination in the organism” and its action mechanism (PK/PD ratio) when polymyxin B or E or neomycin are orally administered for a respiratory condition if they are NOT absorbed. On the other hand, injection of an antibacterial requiring a long permanence in organism (treatments of at least 5 days and where 60% of dosage interval is over CMI every day) to have an optimal antibacterial effect is questionable. Ceftiofur is an example of this suboptimal use which is added to Marek vaccine and is only applied once when an optimal use would be at least 3 days.
[0004] Gentamicin is perhaps the antibacterial with faster destruction of bacteria, but in order to note this effect, the rationale should not be in terms of the time that plasma concentration is above of minimum inhibiting concentration (CMI) but instead in terms of achieving 8 to 10 times the CMI value to optimal bactericidal concentration (COB), unfortunately it is not orally absorbed and it has to be necessarily injected, which is impractical in birds and pigs. On the contrary, there are antibacterial drugs which once that they stop bacterial growth with concentrations equivalent to CMI value or from 2 to 4 times CMI value, they do not achieve a faster effect when concentration is increased, in addition to not to achieve it feasibly at reasonable doses in the organism. It is important in these cases that a sufficient concentration is “always” achieved so as to inhibit growth. Thus, the effects of antibacterial concentrations in terms of CMI and COB (optimal bactericidal concentration) provide a description of the antibacterial activity-time and antibacterial activity-concentration relationship of a given antibiotic family, respectively. Depending on these profiles and their clinical efficacy, two antimicrobial action models have been described, those which are concentration-dependent (CD) and those described as with higher efficacy related with its permanence in the organism or time-dependent (TD).
Time-Dependent Antibacterial Drugs.
[0005] The clinical effect is achieved at its optimal expression when the medicament is administered in such way and through a suitable route as to achieve an almost continuous contact between bacteria and antibacterial. Time-dependent (TD) antibacterial drugs are considered β-lactams, macrolides, tetracyclines, sulfonamides, phenicols, phosphomycin, lincomycin and clindamycin. Optimal destruction rate occurs at certain serum and tissue concentration equivalent or preferably above CMI value but during a maximum time between dosage intervals (ID) (T≧CMI at least 75% ID and preferably during the whole ID). Then, it is not better to provide large doses but separate them in several intakes or instead, having a medicament which achieves a sustained release since at larger concentrations (>Cmax) microorganisms are not destroyed neither faster nor extensively. For β-lactams, for example, clinical efficacy is directly related to T≧CMI, when time above or equivalent to CMI is higher than 40 to 50% of dosage interval it may reach up to 60% of clinical and bacteriological efficacy and when T>CMI is from 60 to 70% of dosage interval, it may provide from 80 to 90% of bacteriological and clinical efficacy. If T>CMI is 100 in ID, then a preparation expressing the highest antibacterial potential has been achieved.
[0006] Above discussion is applicable to several medicaments in addition to antimicrobials. Clinical efficacy is not added by achieving high concentrations for any drug or vitamin or mixture of microelements if they are DT; what is required is a constant supply for optimal effect and for not to cause toxicity.
Concentration-Dependent Antibacterial Drugs (CD)
[0007] There are antibacterial drugs which efficacy depends more directly on the drug reached concentration in the site of action. Values which shall be reached in plasma and tissues shall be the maximum possible and therefore, bolus doses shall be always delivered (all dose in the least possible time), which is actually a problem in case of birds and pigs. Moreover, high-bioavailability proven quality preparations must be used. It is clearly identified that at higher antibacterial concentration, there is a higher bacterial destruction rate and lower mutant selection. The result is that clinical efficacy will be clearly and rapidly manifested. Thus, the pharmacokinetic variables would be Cmax/CMI of at least: 8 to 10 times for aminoglycosides and >10-12 for fluoroquinolones in case of Gram-positive bacteria and of >10 times for aminoglycosides and >12 for fluoroquinolones for Gram-negative bacteria.
[0008] It is also known that they depend on the area under curve rate (AUC) (bioavailability measure) over microorganism CMI being in treatment. This is especially relevant for drugs with long half-life such as fluoroquinolones. Thus, AUC/CMI ratio will be >30-50 for Gram-positive bacteria and >100-125 for Gram-negative bacteria.
[0009] It has been found that with AUC/CMI<100 a 42% clinical and 26% microbiological efficiency may be obtained, and when ratio AUC/CMI is >125 response is usually 80% and 82% as to microbiological. Moreover, this may be increased by increasing the ratio, provided that toxicity is not caused.
[0010] Based on that above, it is apparent that pharmaceutical compositions are necessary to be generated allowing a rational use of antimicrobial drugs in commercial poultry and in pigs; that is, congruent with their PK/PD, for example, through suitable pharmaceutical designs for each antibacterial considering food and water consumption habits of commercial poultry and pigs. For example, it is known that enrofloxacin requires a strategic dosage for commercial poultry with a proper handling of water lines to promote an oral bolus dose in birds and thus provide key pharmacokinetic values for this antimicrobial drug considered as CD, reaching a maximum plasma concentration (Cmax) higher than 12 and a value of area under curve/minimum inhibiting concentration (AUC/CMI) higher than 125. When subject variables are not achieved, a lower clinical response is generated and resistant strain generation is promoted (Lenski, 1998). Management of water lines (Sumano et al., 2000; Dorrestein, 1991) and use of absorption promotings (Sumano & Gutiérrez 2003: Sumano et al., 2004) are actions which are congruent from PK/PD point of view for CD antibacterial drugs and optimize clinical response and productivity in a flock. Enrofloxacin and other fluoroquinolones shall not be administered by a single maneuver of adding to food since they do not achieve suitable Cmax values. This is even more critical in pigs and they must be individually injected thus involving management and cost. It has been noticed in pigs that oral route does not achieve a suitable F and therefore the proper Cmax is not reached, aside from a sick pig drastically reducing its feed and water intake when being sick.
[0011] The situation is critical for time-dependent (TD) antimicrobials as they are applied in feed and generally have short elimination half-lives (T½β) and often suitable therapeutic concentrations are not achieved by night, e.g., tylosin (Gutierrez et al., 2008). In spite of that, there are many DT antimicrobials used in poultry farming; for example: lincomycin and clindamycin, some tetracyclines, florphenicol and tianphenicol, tiamulin, phosphomycin and mixtures of sulfonamides with trimethoprim.
[0012] On the other hand, the precise pharmacokinetics of macrolides such as azithromycin, clarithromycin and roxithromycin is unknown in commercial poultry, which T½β is quite more extended in human beings (McConnell et al., 2006; Nightingale., 1997; Craig, 1997) and which may reach more favorable AUC/CMI variables, as well as 4 times MIC in all ID. However, that results less probable since drug excretion in birds is faster and bioavailability (F) is more reduced both by metabolic rate since almost one half of portal flow directly irrigates kidney (porta-renal) and this produces a remarkable effect of “first step” (Wages, 1997; Puyt, 1997). Furthermore, those macrolides should be assessed for use in poultry farming whether by cost and by being reserved in human medicine.
[0013] But above remarks are not only applicable to macrolides. It is not risky to say that most of poultry farming medicaments are bad designed; even poultry therapeutics icons such as oxytetracycline and chlortetracycline having a quite low bioavailability (F) (20%) and which have performed as antimicrobials with minor success given their potential.
[0014] There are antimicrobials, anticoccidial drugs, analgesics, mucolytics, vitamins, minerals and other medicaments with poorly suitable PK/PD designs within the state of the art; for example:
[0000] In commercial poultry:
Oxytetracycline with F of 20% which leads to dose use up to 1000 ppm. Tylosin (phosphate or tartrate) in water or food with almost zero plasma concentrations by night and low F (<40%). Phosphomycin in water which does not achieve high concentrations in usual doses (10-40 mg/kg/day) and which is removed from plasma and tissues in less than 6-8 hours. Fluoroquinolones which even when not recommended for food medication, they are used in field with extremely low, frequently useless, Cmax results. Its F is 60% in drinking water in experimental models but a 180% F may be reached with this subject invention. Erithromycin with a very low F (18%) and permanence in the organism which does not covers full day and much less by night.
In pigs:
Mixtures of sulfonamides with trimethoprim do not have a synergic effect as in humans since trimethoprim is removed very fast (elimination half-life of 1 hr) and a minimum sulfonamide-trimethoprim 16:1 ratio is respectively required to meet synergy. Lincomycin having a life of 20% or little more, thus limiting its clinical efficacy Spectinomycin only has a 7% F and still synergistic with lincomycin for treatment of some diseases. Tetracyclines require 800 ppm or higher doses to reach 40 mg/kg/day doses as their F is below 40%. Serum concentrations are not reached by night and in breeding sows doses should be 3000 ppm as they only eat an average of 2 kg with a weight of 300 kg. This is obviously not performed as they would reject food. Tylosin and tiamulin are often underdosed due to costs. This fact limits efficacy, especially because they have a low F (not more than 50-60%) and given their fast elimination they show null concentrations by night. The use of fluoroquinolones is currently NOT recommended in feed since high Cmax concentrations are not achieved (at least 12 times CMI) and/or AUC/CMI 125. FOLA system achieves that easily even better than if that would have been injected. Provision of phosphomycin in food is not useful since its F is below 20% and is eliminated in a few hours. Associated to FOLA system the results allow a single dose in the morning with food reaching F close to 100% and during 24 hours.
[0027] In the light of above, the drawbacks shown by prior art prosthetic systems have been intended to be suppressed by developing a new composition of pharmaceutical excipients and forms allowing a remarkable increase in drug bioavailability in poultry, commercial poultry, as well as in pigs in every productive stage, optimizing its dosage and reducing antibacterial waste to the maximum, and further generating bacteria-resistant strains by optimizing drug pharmacokinetics/pharmacodynamics (PK/PD) ratio.
OBJECTS OF INVENTION
[0028] Having in mind the deficiencies of prior art, it is an object of present invention to provide a composition of pharmaceutical forms and excipients to achieve an optimal bioavailability and long action sustained release (FOLA) of any drug in commercial poultry and pigs.
[0029] It is another object of present invention, to provide a composition of pharmaceutical forms and excipients to allow bioavailability (F) to be remarkably increased in antibacterial drugs, analgesics, mucolytics, anticoccidial drugs, vitamins and minerals
[0030] It is an additional object of present invention, to provide a composition of pharmaceutical forms and excipients allowing achievement of maximum response of drugs or added active substances, as they are more time available for absorption in gastrointestinal duct (GI), at a suitable rate to reach F maximum value while extending its permanence in the organism.
[0031] An additional object of present invention is to provide a composition of pharmaceutical forms and excipients administrable to broiler chicken, egg laying birds, egg breeding birds for production of broilers and “grandmothers” (parent breeding birds), ducks, turkeys, geese, quails, ostriches and other commercial poultry, as well as pigs in all productive stages, piglets, breeding stock, fatten, and others.
[0032] It is a further object of present invention, to provide a composition of pharmaceutical forms and excipients which optimizes dosage and reduces drug waste at maximum.
[0033] It is a further object of present invention, to provide a composition of pharmaceutical forms and excipients minimizing the generation of bacteria-resistant strains by optimization of pharmacokinetics/pharmacodynamics (PK/PD) ratio of antibacterial drugs and other drugs, such as NSAIDs, mucolytics, anticoccidial drugs, etc.
[0034] Still another further object of present invention is to provide a composition of pharmaceutical forms and excipients presented in several colors and shapes for identification and differentiation.
[0035] It is another object of present invention to provide a composition of pharmaceutical forms and excipients wherein the form which presents the composition allows birds to select pharmaceutical forms based on their instinct.
[0036] Still another further object of present invention is to provide a composition of pharmaceutical forms and excipients which masks flavor and odor.
BRIEF DESCRIPTION OF FIGURES
[0037] Novel features which characterize present invention will be set forth in attached claims. However, the invention itself will be better understood, both in structural organization and in other objects and advantages thereof, by the following detailed description of certain preferred embodiments when reading together with the attached drawings wherein:
[0038] FIG. 1 shows a chart representing Enrofloxacin administered alone in food or included in FOLA system, in commercial poultry of 750 g±8.4 g, with ad-libitum food and estimating a dose of 8-12 mg/kg/day for food consumption. Note a generation of several enrofloxacin peaks with FOLA system, which makes suitable its PK/PD ratio.
[0039] FIG. 2 shows a chart representing disodium phosphomycin administered alone in food or included in FOLA system, en commercial poultry de 750 g±10.2, with ad-libitum food and estimating a dose of 20 mg/kg/day for food consumption. Note a generation of two phosphomycin peaks with a higher AUC for the second peak with FOLA system, which makes suitable its PK/PD ratio.
[0040] FIG. 3 shows a chart representing Phosphomycin administered alone in food or included in FOLA system, in commercial poultry of 750 g±8.2, with ad-libitum food and estimating for food consumption a 40 mg/kg/day dose. Note a generation of two phosphomycin peaks with a larger AUC for the second peak with FOLA system, which makes suitable its PK/PD ratio.
[0041] FIG. 4 a shows a chart representing tylosin tartrate administered just in food or included in FOLA system, in commercial poultry of 1.9 kg±0.5, with ad-libitum food. Note generation of concentrations quite higher than traditional system (Cmax, MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system.
[0042] FIG. 4 b shows a chart representing tylosin tartrate administered just in food or included in FOLA system, in commercial poultry of 1.9 kg±0.5, with ad-libitum food. Note generation of concentrations quite higher than traditional system, exceeding 1.5 μg/mL (Cmax, MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system.
[0043] FIG. 5 shows a chart representing serum concentrations of tiamulin fumarate along a day, administered just in food or included in FOLA system, in commercial poultry of 2.1 kg±0.6, with ad-libitum food. Note generation of concentrations quite higher than traditional system (Cmax, MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system.
[0044] FIG. 6 shows a chart representing tiamulin fumarate administered just in food or included in FOLA system during 6 days, in commercial poultry of 2.0 kg±0.6, with ad-libitum food. Note generation of concentrations quite higher than traditional system (Cmax, MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system.
[0045] FIG. 7 shows a chart representing serum concentrations of florphenicol along a day, administered just in food or included in FOLA system, in commercial poultry of 500 g±8, with ad-libitum food at 10 mg/kg. Note generation of concentrations higher than traditional system (MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system. It is remarked that Cmax is not pharmacologically significant for florphenicol.
[0046] FIG. 8 a shows a chart representing serum concentrations of florphenicol along three days administered just in food or included in FOLA system, in commercial poultry of 450 g±9, with ad-libitum food at 20 mg/kg. Note generation of concentrations higher than traditional system (Cmax, MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system.
[0047] FIG. 8 b shows a chart representing serum concentrations of florphenicol along three days administered just in food or included in FOLA system, in commercial poultry of 450 g±9, with ad-libitum food at 20 mg/kg. Note a generation of concentrations lower than 3 μg/mL, making suitable its PK/PD ratio when included in FOLA system.
[0048] FIG. 9 shows a chart representing serum concentrations of trimethoprim and sulfachloropyridazine sodium administered as premixture (5:1) (25 mg/kg of sulfonamide and 5 mg/kg of trimethoprim, in both cases) as conventionally in food or including active substances in FOLA system. Commercial poultry of 450 g±6, with ad-libitum food was used. Note generation of concentrations higher than traditional system (MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system. It is worth to remark that Cmax is not pharmacologically significant for this mixture, and a noteworthy feature of FOLA system is allowing a continued synergy during the whole dosage range and not only during the first 5 hours.
[0049] FIG. 10 a shows a chart representing serum concentrations of oxytetracycline administered as premixture as conventionally in food or included in FOLA system. Commercial poultry of 700 g±6, with ad-libitum food was used and dosed at a 600 ppm rate. Note generation of concentrations higher than traditional system (Cmax, MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system. Note a significant improvement in bioavailability.
[0050] FIG. 10 b shows a chart representing serum concentrations of oxytetracycline administered as premixture as conventionally in food or included in FOLA system related to any day hour. Commercial poultry of 700 g±6, with ad-libitum food was used and dosed at a 600 ppm rate. Note generation of concentrations higher than traditional system (Cmax, MRT and AUC), which makes suitable its PK/PD ratio when included in FOLA system. Note a significant improvement in bioavailability.
[0051] FIG. 11 shows a chart representing serum concentrations of 3 days of tilmicosin administered alone in food or included in FOLA system, in commercial poultry of 750 g±8, with ad-libitum food at a rate of 400 ppm. Note generation of concentrations higher than traditional system (Cmax, MRT and AUC) and a much more remarkable cumulative trend with FOLA system, which makes suitable its PK/PD ratio.
DETAILED DESCRIPTION OF INVENTION
[0052] The present invention discloses compositions within a large variety of antimicrobials, anticoccidial drugs, analgesics, vitamins, mucolytics, minerals and other drugs by manipulation of the pharmaceutical form and excipients used for notoriously increasing their bioavailability (F), frequently their Cmax and to extend their duration or permanence in bird and pig organisms, with an optimal pharmacokinetics (drug destination in bird's organism) with pharmacodynamics (mechanism whereby they exert their effect at cell or tissue level) ratio (PK/PD) and which results in better clinical efficacy in each medicament.
[0053] Compositions subject of present invention comprise the form, composition, size and color of solid shapes which contribute for selection and consumption by birds and pigs, since the medicament is usually mixed with food. For example, in poultry such as hens, they tend to select those foods with shapes equivalent to cereal grains, worms and other organic forms and specific colors. As to pigs, flavor is masked thus leading to a better acceptance and a remarkable increase of F in antibacterial drugs, analgesics, mucolytics, anticoccidial drugs, beta-adrenergic agonists such as ractopamin, vitamins and minerals.
[0054] The compositions subject of present invention comprise:
about 10 to 70% of one or more pharmaceutically active agents, selected from the group comprising: antimicrobials, anticoccidial drugs, analgesics, vitamins, mucolytics, minerals, and others; about 0.5 to 20% of one or more bioavailability promoting agents, selected from the group consisting of capsaicin and derivatives, grapefruit and its extracts, cyclodextrines, labrasol, sodium caproate (0.25%) sodium desoxycholate (1.0%), hexadecyldimethylbenzylammonium chloride, hexylsalicylic acid, polyacrylic acid cysteine/glutathione reduced of chitosan-4-thio-butylamide (chitosan-TBA)/reduced glutathione, EDTA and TRIS. about 20 to 80% of one or more polymers for drug sustained release selected from the group consisting of poloxamer, carbopol, methocel, β-cyclodextrin, poli (D, L lactide) (PDLA), poli (L-lactide) (PLLA), tragacanth gum (high concentration), guar gum, karaya gum (high concentration), sodium alginate, gelatin, chitosan; cellulose derivatives such as methylcellulose (low molecular weight), sodium carboxymethylcellulose (low, medium and high molecular weight), hydroxyethyl-cellulose, hydroxypropylcellulose, poliethyleneglycols (high molecular weight), polyvinyl alcohol, carbopol, acrylic and methacrylic acid polymers and copolymers, polyalkylcyanoacrylates, polycarbophil, polyacrylic acid, sodium alginate and hydroxypropylmethylcellulose, carbopol 934 and EX55, carragenate, guar gum, methylcellulose 10 cPs, polyacrylamide, polycarbophil, tragacanth, polyacrylic acid crosslinked with sucrose, polymethacrylic acid, carbopol base with petroleum jelly/hydrophilic paraffin, katara gum, acacia, alginic acid, agar-agar, pectin and amilopectin, calcium carboxymethylcellulose, polyhydroxyethylmethacrylate (PHEMA), methylcellulose, higher than 100 cPs, polyvinylpyrrolidone, degraded carragenate, dextrans and other polymers; about 0.01 to 1% of one or more food grade or animal consumption colorants; and about 0.1 to 5% of natural or artificial flavorants.
[0060] This composition is mixed and extruded to provide shape and appearance allowing a better acceptance by any bird or pig.
[0061] The compositions subject of present invention are also characterized by comprising drugs preferably selected from the group of time-dependent antimicrobials but also some concentration-dependent drugs such as: tylosin, tiamulin, tilmicosin, enrofloxacin and other fluoroquinolones, phosphomycin, florphenicol, oxytetracycline, doxycycline, erithromycin and other macrolides, clortetracycline, sulfonamides with trimethoprim, and others.
[0062] The compositions subject of present invention, preferably comprise those colorants corresponding to red, yellow, green and orange hues, as well as their combinations. Shapes which the compositions subject of present invention are extruded into are varied, including spheres, cylinders, flat or cylindrical worms, straight or curved, coiled, irregular flat or filled shapes, etc.
[0063] The compositions of excipients and pharmaceutical forms with sustained release and increase in drug bioavailability are prepared by following the procedure described below:
[0064] Drug or active substance is dry mixed with the bioavailability promoting agent(s), one or more agents destined to achieve sustained release or long action are then added. These ingredients are mixed until homogenizing the mixture, and adding colorants or flavorants as required. Once a homogeneous mixture is achieved, from 10 to 60% by weight of the water total mixture is added, mixing until obtaining a mass of dry to semi-dry and soft consistency.
[0065] The soft and dried mass is poured into extrusion equipment, its nozzle being adapted with the physical shape of the above mentioned selected pharmaceutical shape. Extruded fragments are dried at room temperature, protected from light and air.
[0066] Obtained product is the composition of pharmaceutical forms and excipients with sustained release and increase in drug bioavailability for poultry and pigs which optimizes drug dosage and reduces waste thereof; minimizes generation of bacteria-resistant strains by optimizing pharmacokinetics/pharmacodynamics ratio in drugs and further masking drug flavor and odor.
[0067] Compositions of pharmaceutical excipients and forms were prepared by above procedure, which were tested in birds and pigs, according to the examples described below. The present invention will be better understood from the following examples which are only provided for illustrative purposes allowing a full understanding of the preferred embodiments of present invention, not excluding that there are other non-illustrated embodiments which may be practiced based on above disclosed detailed description.
[0068] Examples below are described illustratively but not limiting the scope of the invention.
Examples
Tests in Commercial Poultry
Example 1
Enrofloxacin
[0069] As to enrofloxacin, a fluoroquinolone which according to worldwide standards SHALL NOT be administered in food and nevertheless, an exceptional pharmacokinetics is achieved with FOLA-enrofloxacin, better than any known fluoroquinolone at this date. Data are revealing a unique therapeutic potential as shown below.
[0070] 10 grams of enrofloxacin
[0071] 20 grams of methocel
[0072] 30 grams of wheat flour
[0073] 1 mg of a food grade green colorant, following the previously described procedure.
[0074] Pharmaceutical form was obtained in the form of a little stone as irregular spheres:
[0075] Single doses of 10 mg/kg were administered in food ad libitum* or in drinking water **, obtaining the results which are illustrated in FIG. 2 , chart 1, comparing with the results obtained by administering commercially available enrofloxacin.
[0000]
Dose in
AUC/CMI
Cmax/CMI
food* or
AUC
Cmax
(w/o
(w/o
Fr
Drug
in water**
(μg/mL/h)
(μg/mL)
units)
units)
(%)
Enrofloxacin
10 mg/kg*
156.3
10.23
2605
170.5
1766
in FOLA
Enrofloxacin
10 mg/kg**
8.85
4.2
147
70
100
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case E. coli (0.06 μg/mL).
Cmax/CMI = valuw which must be 10-12 or above if possible in fluoroquinolones.
Fr = Relative bioavailability achieved with formula
AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to bird age
Example 2
Phosphomycin
[0076] Following is detailed a manufacturing procedure of FOLA-disodium phosphomycin as disodium phosphomycin is a very common antibacterial drug in Latin America, and data from two assays are presented wherein a huge difference is apparent between a F achieved with commercially obtained disodium phosphomycin reference premixture and that achieved with FOLA system, in these cases using a dose of 20 and 40 mg/kg/day in food ad libitum with both preparations.
[0077] A composition was prepared by mixing 3 grams of phosphomycin, about 0.5 grams of Methocel, about 6.5 grams of wheat flour and 5 mg of food grade green colorant, extruding this mixture in spherical forms.
[0078] Variables disclosed below are pharmacokinetically obtained for disodium phosphomycin in FOLA and a commercially available reference preparation. Charts 2A and 2B illustrate the obtained results.
[0000]
Single dose of 20 mg/kg in food ad libitum*
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/mL/h)
(μg/mL)
(w/o units)
(%)
Disodium
10 mg/kg
714.04
11.36
7140.4
phosphomycin
en FOLA
Disodium
10 mg/kg
42.17
11.15
421.7
phosphomycin
commercially
available
[0000] Single dose of 40 mg/kg in food ad libitum* Dose in AUC Cmax AUC/CMI Drug food* (μg/mL/h) (μg/mL) (w/o units) Disodium 10 mg/kg 1422.12 23.58 14221.2 phosphomycin en FOLA Disodium 10 mg/kg 83.26 21.36 832.6 phosphomycin commercially available AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference). Cmax = maximum serum or plasma concentration AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Haemophilus gallinarum (0.1-0.4 μg/mL). Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100. *Estimating a daily food consumption according to bird age
Examples with Other Antibacterial Drugs in Birds and Pigs
[0079] Compositions of excipients and pharmaceutical forms with sustained release and increase in bioavailability were similarly prepared with oxytetracycline, florphenicol, tilmicosin, tylosin, tiamulin, and sulfachloropyridazine sodium with trimethoprim to be administered in birds; compositions were prepared for administration to pigs by using about 30% by weight of drug; about 5% of one or more bioavailability promoting agents, selected from the group consisting of capsaicin, grapefruit extracts, cyclodextrins, labrasol, sodium caprate (SC, 0.25% w/v, sodium desoxycholate (SD, 1.0% w/v), hexadecyldimethylbenzylammonium chloride, hexylsalicylic acid, polyacrylic acid cysteine/glutathione reduced of chitosan-4-thio-butylamide (chitosan-TBA)/reduced glutathione, EDTA and TRIS; about 65% of one or more drug sustained-release polymers selected from the group consisting of poloxamer, carbopol, methocel, β-cyclodextrin, poly (D, L lactide) (PDLA), poly (L lactide) (PLLA), tragacanth gum (high concentration), guar gum, karaya gum (high concentration), sodium alginate, gelatin, chitosan; cellulose derivatives such as methylcellulose (low molecular weight), sodium carboxymethylcellulose (high molecular weight), hydroxyethyl cellulose, hydroxypropylcellulose, polyethylene glycols (high molecular weight), polyvinyl alcohol, carbopol, acrylic and methacrylic acid polymers and copolymers, polyalkylcyanoacrylates, polycarbophil, chitosan, polyacrylic acid, Sodium alginate, Carbopol and hydroxypropylmethylcellulose, Carbopol 934 and EX55, Sodium carboxymethylcellulose, Carragenate, Guar gum, Hydroxyethyl cellulose, Methyl cellulose 10 cPs, Polyacrylamide, Polycarbophil, Tragacanth, Sucrose-crosslinked polyacrylic acid, polymethacrylic acid, Carbopol base with petroleum jelly/hydrophilic paraffin, katara gum, Hydroxypropyl cellulose, Acacia, alginic acid, Agar-agar, Amilopectin, Calcium carboxymethylcellulose, Polyhydroxyethylmethacrylate (PHEMA), Methylcellulose, higher than 100 cPs, Pectin, Polyethylene glycol, Polyvinylpyrrolidone, degraded Carragenate, and Dextrans; and about 0.5% of a colorant selected from the group which tones are red, orange, Green and yellow; extruded in shapes of cylinders, spheres, irregular spheres, worms, screws, and others.
[0000] Obtained results are shown below:
Example 3
Tylosin
[0080] For Tylosin in commercial poultry, very high concentrations are achieved when FOLA system is used and which remain with therapeutic effect along night as shown in charts of FIGS. 4 a and 4 b . Variables disclosed below are pharmacokinetically obtained for tylosin in FOLA and a commercially available reference preparation:
[0000]
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food
(μg/mL/h)
(μg/mL)
(w/o units)
(%)
Tylosin
200 ppm
18.4
1.13
184
868
tartrate
in FOLA
Tylosin
200 ppm
2.12
0.2
2.0
100
tartrate
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Mycoplasma spp (0.1 μg/mL).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100
Example 4
Tiamulin
[0081] The following representative results are shown for tiamulin, as illustrated in the chart of FIG. 5 . Variables disclosed below are pharmacokinetically obtained for tiamulin in FOLA and a commercially available reference preparation:
[0000]
Dose of 50 mg/kg/day per 6 days, ad libitum*.
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/mL/h)
(μg/mL)
(w/o units)
(%)
Tiamulin
50 mg/kg
93.75
6.25
937.5
535.71
en FOLA
Tiamulin
50 mg/kg
17.50
3.81
175.0
100
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Mycoplasma spp (0.6-1.5 μg/mL for sensitive microorganisms and de 1.5 a 2.6 μg/mL).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to bird age
[0082] When the study is extended by 6 days, the medication provides the results shown in the chart of FIG. 6 . Variables disclosed below are pharmacokinetically obtained for tiamulin en FOLA and a commercially available reference preparation:
[0000]
Single dose of 50 mg/kg in food ad libitum*
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/mL/h)
(μg/mL)
(w/o units)
(%)
Tiamulin
50 mg/kg
104.2
6.82
69.46
268.4
in FOLA
Tiamulin
50 mg/kg
52.9
3.84
35.26
100
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Mycoplasma spp (0.6-1.5 μg/mL for sensitive microorganisms and de 1.5 a 2.6 μg/mL)
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100
*Estimating a daily food consumption according to bird age
Example 5
Florphenicol
[0083] Multiple assays were conducted for florphenicol using doses of 10 mg/kg in food, with estimated daily food consumption according to bird age. Results are shown in the chart of FIG. 7 . Variables disclosed below are pharmacokinetically obtained for florphenicol in FOLA and a commercially available reference preparation:
[0000]
Single dose of 10 mg/kg in food ad libitum*
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/mL/h)
(μg/mL)
(w/o units)
(%)
Florphenicol
10 mg/kg
38.15
3.8
381.5
244.55
in FOLA
Florphenicol
10 mg/kg
15.6
4.5
156.0
100
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Haemophilus gallinarum (0.1-0.4 μg/mL).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to bird age
Example 6
Sulfachloropyridazine Na Con Trimethoprim
[0084] It is worth to remark that a synergy as that expected in vivo is not achieved under normal conditions for a mixture of sulfachloropyridazine Na with trimethoprim. This is due to a fast elimination of trimethoprim in birds (T½β=1 hour vs. T½β in humans=10 hours). A true synergy is achieved with FOLA system while keeping concentrations of at least 16-20 parts of sulfonamide per 1 of trimethoprim during the whole dosage range, this ratio being necessary to keep synergy.
[0085] The chart in FIG. 9 presents the constant in sulfachloropyridazine+trimethoprim concentrations in (5:1) ratio and dosed together at a rate of 25 mg/kg of sulfonamide and 5 mg/kg of trimethoprim in food and using a commercial preparation as reference. Assessment of sulfonamide and trimethoprim concentrations was made by high resolution liquid chromatography. Obtained results are shown below in quadruplicate.
[0086] Variables disclosed below are pharmacokinetically obtained for sulfachloropyridazine Na and trimethoprim in FOLA and with a commercially available reference preparation:
[0087] Single dose of 25 mg/kg de sulfachloropyridazine Na and 5 mg/kg de trimethoprim in food, ad libitum*
[0000]
SULFACHLOROPYRIDAZINE - Na
Dose
AUC/CMI
SCP-
in
AUC
Cmax
(w/o
Fr
Na/TMP
Drug
food*
(μg/mL/h)
(μg/mL)
units)
(%)
Ratio
Sulfachloropyridazine
20 mg/kg
241.4
16.8
60.35
226
5.5/1
Na
de
in FOLA
SCP-Na
and 4 mg/kg
de TMP
Sulfachloropyridazine
20 mg/kg
107.5
17.3
26.75
100
4.8/1
Na,
de
commercially
SCP-Na
available
and 4 mg/kg
preparation
de TMP
[0000]
TRIMETHOPRIM
Dose in
AUC
Cmax
Fr
Drug
food*
(μg/mL/h)
(μg/mL)
(%)
Trimethoprim
4 mg/kg
54.35
2.9
610.7
in FOLA
de SCP-Na
and 4 mg/kg
de TMP
Trimethoprim
4 mg/kg
8.9
3.6
100
of a commercially
de SCP-Na
available
and 4 mg/kg
preparation
de TMP
SCP-Na = sulfachloropyridazine Na
TMP = trimethoprim
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case E. coli (4-10 μg/mL para SCP-Na and de 1-2 para TMP and de 0.4-1 para la acción conjunta de SCP-Na con TMP).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to bird age
Example 7
Oxytetracycline
[0088] Oxytetracycline has been and still remains as the most successful antibacterial drug ever sold in the history of animal production (birds and pigs), administered as premixture; however, oxytetracycline base bioavailability in chickens and commercial poultry fluctuates around 20%. In such a way that high concentrations in food must be used for a minimum effect and somehow questionable concentrations when considering that CMI for E. coli is 2.5 μg/mL. As noticed, unprecedented serum concentrations with FOLA system at a 600 ppm dose are achieved, and thus PK/PD congruence for an antibacterial drug having been irrationally used for more than half a century. Obtained results are shown in charts from FIGS. 10 a and 10 b.
[0089] Variables disclosed below are pharmacokinetically obtained for oxytetracycline in FOLA and a commercially available reference preparation:
[0000]
Dose of 600 ppm in food ad libitum*
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/Ml/h)
(μg/mL)
(w/o units)
(%)
Oxytetracycline
600 ppm
659.45
0.6
6594.5
705.89
in FOLA
Oxytetracycline
600 ppm
93.42
3.6
934.2
100
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Haemophilus gallinarum (0.1-0.4 μg/mL).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to bird age
Tests in Birds and Pigs
Example 8
Oxytetracycline
[0090] Chart 8 shows obtained results. Variables disclosed below are pharmacokinetically obtained for oxytetracycline in FOLA and a commercially available reference preparation administered during 3 days:
[0000]
Single dose of 1200 ppm in food ad libitum*
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/Ml/h)
(μg/mL)
(w/o units)
(%)
Oxytetracycline
1200
168.9
3.84
232.8
in FOLA
ppm
Oxytetracycline
1200
72.6
1.62
100.00
commercially
ppm
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Haemophilus suis (0.1-0.4 μg/mL).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to pig age
Tests in Commercial Poultry
Example 9
Florphenicol
[0091] Chart in FIG. 8 b shows obtained results. Variables disclosed below are pharmacokinetically obtained for florphenicol in FOLA and a commercially available reference preparation administered during 3 days:
[0000]
Single dose of 20 mg/kg in food ad libitum*
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/Ml/h)
(μg/mL)
(w/o units)
(%)
Florphenicol
20 mg/kg
130.1
2.76
220
FOLA
Florphenicol
20 mg/kg
59.15
1.31
100
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Haemophilus suis (0.1-0.4 μg/mL).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to pig age
Example 10
Tilmicosin
[0092] Chart in FIG. 11 shows obtained results. Variables disclosed below are pharmacokinetically obtained for Tilmicosin in FOLA and a commercially available reference preparation administered during 3 days:
[0000]
Multiple dose of Tilmicosin 400 ppm in food ad libitum*
Dose in
AUC
Cmax
AUC/CMI
Fr
Drug
food*
(μg/Ml/h)
(μg/mL)
(w/o units)
(%)
Tilmicosin
20 mg/kg
89.3
1.92
311.7
FOLA
Tilmicosin
20 mg/kg
28.65
100
commercially
available
AUC = area under curve of drug concentration vs time with FOLA system or with the commercially available preparation (reference).
Cmax = maximum serum or plasma concentration
AUC/CMI = ratio between AUC value divided by minimum inhibitory concentration of a pathogen, in this case Haemophilus suis (0.1-0.4 μg/mL).
Fr = Relative bioavailability achieved with formula AUC FOLA /AUC reference × 100.
*Estimating a daily food consumption according to pig age
[0093] Even though certain embodiments of the invention have been illustrated and described, it should be noted that a number of modifications thereof are possible, but such modifications do not represent a distance from the true scope of the invention. Therefore, the present invention shall not be considered restricted except by the provisions in the state of the art, as well as the scope of the attached claims.
REFERENCES
[0000]
1. Craig W A. Antimicrobial resistance issues of the future. Diagn Microbial Infect Dis. 1996; 25:213-217.
2. Dorrestein, G. M. and A. S J. P A. M. Van Miert. Pharmacotherapeutic aspects of medication of birds. J Vet Pharmacol Ther 1988. 11:33-44.
3. Dorrestein, G. M. The pharmacokinetics of avian therapeutics. Vet Clin North Am Small Anim Pract 1991. 21:1241-1261.
4. Pigan, D. and R, Kolter. 2002. Why are bacteria refractory to antimicrobials. Curr. Opin. Micro. 5:472-477.
5. Lenski, R. E. (1998). The cost of antibiotic resistance—from the perspective of a bacterium. Ciba Found Symp 207, 131-140.
6. McConell J, 2006, New Orraly active carbapanem trial results announced. Lancet Infect Dis. 6: 265-266
7. Nightingale C. H., Pharmacokinetics and pharmacodynamics of newer macrolides. Pediatr. Infect. Dis. J. 16 (1997), pp. 438-443.
8. Puyt J. D., Antibiotic therapy in poultry production. Bulletin des Groupments Techniques Vétérinaires 5 (1995), pp. 17-110
9. Sumano L. H, & Gutierrez O. L. (2003) Strategic administration of enrofloxacin in poultry to achieve higher maximal serum concentrations. The Veterinary Journal. 165, 143-148.
10. Sumano L. H, Gutierrez O. L & Ocampo C. L. (2006) Bioequivalence comparison of seventeen commercial oral enrofloxacins against the original preparation in broilers. Journal of Poultry Science. 43, 23-28.
11. Sumano L. H. & Gutierrez, O. L. (2000). Problemática del use de la enrofloxacin en la avicultura en México. Veterinaria México , 31, 137-145.
12. Sumano L. H., Gutierrez O. L. & Zamora Q. M. A. (2000). Bioequivalence of six trademarks of enrofloxacin in poultry. Journal of Veterinary Pharmacology and Therapeutics. 24, 1-5.
13. Sumano L. H., Gutierrez O. L., Aguilera R., Rosiles, M. R., Bernad B. M. J. & Gracia M. J. (2004). Influence of hard water on the bioavailability of enrofloxacin in broilers. Poultry Science. 83, 726-781.
14. Wages, D. P. (1997). Proper medication procedures. Poultry Digest. 56 | The invention relates to a composition of excipients and pharmaceutical forms of sustained release and increased drug bioavailability for poultry and pigs and to a method of producing the same, said composition comprises: pharmaceutically active agents, bioavailability promoting agents, polymers for prolonged release of the drug, colouring agents, and flavouring agents. The composition of excipients and pharmaceutical forms of the invention optimizes the dosing of the drug dosage and generates resistant strains of bacteria by optimizing the ratio between pharmacokinetics/pharmacodynamics of drugs. The composition has different forms and colours that allow the product to be identified and accepted more easily by the bird or pig. | 0 |
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