CA2264091A1

CA2264091A1 - Tubing joints and methods for attachment of tubing to valves and extrusions

Info

Publication number: CA2264091A1
Application number: CA002264091A
Authority: CA
Inventors: Joseph L. Asta; Christos Vassiliou
Original assignee: Individual
Current assignee: Harper Wyman Co
Priority date: 1997-04-15
Filing date: 1998-03-31
Publication date: 1998-10-22
Also published as: BR9815488A; WO1998046924A1

Abstract

A method and apparatus for attachment of tubing to gas valves and similar gas extrusions (104) and tubing joints (100, 100A, 100B) are provided. A gas extrusion body portion (106) is provided with a bore (108) for receiving a small diameter, thin wall tube (102). A groove (110, 110A, 110B, 140, 150, 152, 154, 156) is formed around the exterior of the body portion. The tube (102) having an outside diameter less than an inside diameter of the bore (108) and a flanged eyelet (160), is inserted in the bore. Force is applied to the body portion (106) for deforming an area of the body portion near the groove together with the tube (102) to achieve a mechanical bond, providing a gas tight seal.

Description

?WO 98/46924101520CA 02264091 1999-02-24PCT/US98/06291-1-TUBING JOINTS AND METHODS FOR ATTACHMENT OF TUBING TOVALVES AND EXTRUSION8Field of the InventionThe present invention relates to an improved methodfor attachment of tubing to valves and extrusions andtubing joints for domestic gas appliances.Description of the Prior ArtVarious methods are known for connecting tubingwith small diameter to various types of connectingfittings and extrusions used with domestic gasappliances. In the environment of domestic gasappliances, such as a gas stove, tubing attachments toan outlet or inlet portion of a gas valve or otherextrusions need to reliably provide and maintain fluidtight seals. A problem with one known arrangement isthat when rotational force is applied to the tube, thetube may be caused to rotate so that the gas tight sealis compromised. Typically extremely soft tube materialis used so that handling problems can occur duringshipping and installation of the tubing. Also acompression fitting often is used for connection of thetubing to a gas valve, adding to the total cost of thesystem in both material and labor expense.?WO 98/46924101520253035CA 02264091 1999-02-24PCT/US98/06291-2-For example, U.S. patent 3,711,132 discloses ametal tube end fitting including axially spacedcircumferential grooves within the bore of an endfitting to which a metal tube is attached by radialexpansion are provided with a special contour. Thegroup of grooves nearest the exterior of the fitting isprovided with inclined sidewalls, while the inneradjacent group is provided with perpendicular sidewalls.In the process of assembly, the perpendicular sidewallgrooves are substantially filled by the metal of thetubing while the inclined sidewall grooves are onlypartially filled.U.S. patent 3,977,710 discloses a tube fittingassembly including a fitting having a first bore througha portion of the fitting and a second bore larger thanthe first bore and concentric with and through a portionof the first bore. A tubing having a diametersubstantially equal to the first bore engages an insidesurface of the fitting defined by the end of the firstbore. A sleeve having an outwardly extending projectionreceives the tubing with the projection located withinthe second bore. Relative movement between the fittingand the tubing radially expands the tubing wall toengage the first and second bores and deforms the sleeveprojection outwardly from the tubing to engage thesecond bore by action of the radial expansion of thetubing wall.U.S. patent 4,200,314 discloses a tube fittingassembly including a fitting having a first bore througha portion of the fitting and a second bore larger thanthe first bore and concentric with and through a portionof the first bore. A tubing having a diametersubstantially equal to the first bore engages an insidesurface of the fitting defined by the end of the firstbore. Relative movement between the fitting and the?WO 98/46924101520253035CA 02264091 1999-02-24PCT/US98/06291-3-tube deforms the tubing wall to engage the first andsecond bores and to form an annular bead of the tubingwall outside of the fitting assembly. The bead isswaged into engagement with an outside surface of thefitting surrounding the second bore.U.S. patent 5,492,376 discloses a connecting andfitting method provided for metallic pipes with a smalldiameter. The method includes providing a pipingcomponent having a tube wall extending therefrom anddefining an expanded chamber. The method furtherincludes providing a pipe member and forming at leastone circumferential discontinuity in the pipe membernear one end. The end of the pipe member is theninserted through an annular sealing component and intothe expanded chamber defined by the tube wall. Adiameter reducing area is then formed on the tube wallat a location substantially registered with thecircumferential discontinuity in the pipe member tosqueeze and tightly seal the sealing component intoconnecting engagement with the circumferentialdiscontinuity on the pipe member.U.S. patent 5,573,285 discloses a tubeâfittingassembly including a formed tube, first and secondthreaded fitting member, and a scaling member. The tubehas a first annular bead near an end of the tube and asecond annular bead outboard of the first annular head.The first threaded fitting member surrounds the tube andhas a radially inwardly extending first shoulder inboardof the first and second annular beads. The secondthreaded fitting member has an annular second shoulderat an acute angle to a longitudinal axis of the tube.The second fitting member surrounds the end of the tubeand is in threaded engagement with the second threadedmember such that the second should engages an outboardside of the second bead to establish a first seal?WO 98/469241015202530CA 02264091 1999-02-24PCT/US98/06291-4-between the tube and the second fitting member againstleakage of fluid pressure. The sealing member is awasher or O-ring which surrounds the tube and engagesthe tube and at least one of the first and secondthreaded fitting members to establish a second sealagainst leakage of fluid pressure at temperatures whichmay relax the second fitting member and break the firstseal. In a preferred embodiment the sealing member ismade of silicone to maintain the second seal at therelatively high temperatures.A need exists for an improved method for attachmentof tubing to valves and extrusions. It is desirable toprovide more flexibility in the selection of tubingmaterials used to form the tubing joints. It isdesirable to provide an improved method for attachmentof tubing to valves and extrusions and resulting tubingjoints that provide effective and reliable operation.summary of the InventionA principal object of the present invention is toprovide an improved method for attachment of tubing tovalves and extrusions. other objects are to provide anew and improved method and tubing joints that provideeffective and reliable operation; and to provide suchmethod and tubing joints that overcome many of thedisadvantages of prior art arrangements.In brief, a method and apparatus for attachment oftubing to valves and extrusions and tubing joints areprovided. An extrusion body portion is provided with abore for receiving a tube. A groove is formed aroundthe exterior of the body portion. The tube having anoutside diameter less than an inside diameter of thebore, is inserted in the bore. Force is applied to thebody portion for deforming an area of the body portion?WO 9814692410152025CA 02264091 1999-02-24PCT/US98/0629]-5-near the groove together with the tube to achieve amechanical bond.In accordance with features of the invention,multiple spaced apart grooves can be formed around theexterior of the body portion to provide multiple seals.One or more of the grooves can be generally cylindricaland/or generally elliptical.Brief Description of the DrawingsThe present invention together with the above andother objects and advantages may best be understood fromthe following detailed description of the preferredembodiments of the invention illustrated in thedrawings, wherein:FIG. 1 is a perspective view illustrating a tubingjoint resulting from the method for attachment of tubingto valve body or extrusion of the preferred embodiment:FIG. 2 is a sectional view taken along line 2-2 ofFIG. 17FIGS. 3 and 4 are sectional views illustratingsuccessive steps in the method for attachment of tubingto valves and extrusions and illustrating how the sealbetween the tubing and valve body of FIGS. 1 and 2 isformed:FIG. 5 is a sectional view similar to FIG. 3illustrating an alternate valve body extrusion portionof the preferred embodiment:FIGS. 6, 7 and 8 are enlarged sectional views ofalternately configured grooves of the valve bodyextrusion portion of the preferred embodiment;?WO 98/469241015202530CA 02264091 1999-02-24PCT/US98/06291-6-FIG. 9 is a sectional view similar to FIG. 2illustrating an alternative elliptical groove of thevalve body extrusion portion used in the method forattachment of tubing to valves and extrusions of thepreferred embodiment:FIG. 10 is a sectional view illustrating analternative tubing joint and the resulting seal betweenthe tubing and the alternative elliptical groove of thevalve body extrusion portion of FIG. 9;FIG. 11 is a sectional View similar to FIG. 2illustrating another alternative arrangement withmultiple cylindrical grooves of the valve body extrusionportion of the preferred embodiment;FIG. 12 is a sectional View similar to FIG. 2illustrating another alternative arrangement with onecylindrical groove and one elliptical groove of thevalve body extrusion portion of the preferredembodiment;FIG. 13 is an exploded perspective viewillustrating an alternative arrangement for attachmentof tubing to valve body or extrusion including a flangedeyelet of the preferred embodiment:FIGS. 14 and 15 are sectional views illustratingsuccessive steps in the method for attachment of tubingto valves and extrusions and illustrating how the sealsbetween the tubing and valve body of FIG. 13 is formed;FIG. 16 is an exploded perspective viewillustrating another alternative arrangement forattachment of tubing to valve body or extrusionincluding a flanged eyelet of the preferred embodiment;?WO 98/469241015202530CA 02264091 1999-02-24PCT/US98/06291-7-FIGS. 17 and 18 are sectional views illustratingsuccessive steps in the method for attachment of tubingto valves and extrusions and illustrating how the sealsbetween the tubing and valve body of FIG. 16 is formed:FIG. 19 is a perspective view illustrating anotheralternative of the valve body extrusion portion used inthe method for attachment of tubing to valve body orextrusion also including a flanged eyelet of thepreferred embodiment:FIGS. 20 and 21 are sectional views illustratingsuccessive steps in the method for attachment of tubingto valves and extrusions and illustrating how the sealsbetween the tubing and valve body of FIG. 19 is formed.Detailed Description of the Preferred EmbodimentsHaving reference to the drawings, FIGS. 1-4illustrate a tubing joint generally designated by thereference character 100 of the invention. Attachment ofa small diameter tube or tubing 102 to a valve body 104or other extrusion is provided with a valve body portion106 receiving the tubing 102. The valve body portion106 has a bore 108 receiving the tubing 102 and havingan inner diameter approximately equal to an outerdiameter of tubing 102. Referring to FIG. 3, a groove110 initially is formed by drilling or machining aroundthe exterior of valve body portion 106. Groove 110 isgenerally cylindrical extending around the exterior ofthe valve body portion 106. FIGS. 3 and 4 illustratesuccessive steps of the attachment method of theinvention, illustrating how the sealed tubing joint 100between the tubing 102 and valve body portion 106 isformed. In FIG. 3, a force is applied to the valve bodyportion 106 via a swage or die member 112 longitudinallyalong the tube 102 as indicated by arrows labeled F as?WO 98/46924101520253035CA 02264091 1999-02-24PCT/US98/06291-8-shown in FIGS. 3 and 4. An applied impact force causesthe initial groove 110 to collapse causing an area 114of valve body portion 106 near the initial groove 110 todeform together with a tubing portion 116 to achieve amechanical bond forming the tubing joint 100, shown inFIG. 4. Sealing portions 114 and 116 form a mechanicalbond defining the tubing joint 100. FIGS. 1 and 2 alsoillustrates the completed tubing joint 100.Alternatively, the tubing joint 100 can be formed bycrimping or rolling techniques. The initial groove 110can be crimped or rolled, to deform together the valvebody portion 114 and the tubing portion 116 to form thetubing joint 100.In accordance with features of the attachment-method of the invention, all of the required machiningto form the initial groove 110 is done external to theattachment area 114, 116 of tubing joint 100. As aresult, flexibility is provided as to the time or stageof the valve making process, this machining operation isperformed. Further conventional drilling and millingtechniques can be used to form the initial groove 110.Extrusion body portion 106 advantageously is formedof a conventional material uses for gas valves andsimilar extrusions, such as an aluminum, grade or type6262T6. Tubing 102 advantageously is formed ofaluminum, such as aluminum, grade or type 6061-T6 or3003-0. Tubing is a small diameter tube, having a wallthickness of 0.028 inch or 0.035 inch and an outerdiameter (0. D.), for example, of 0.250 inch, 0.281inch, 0.291 inch or 0.375 inch. The bore 108 has aninside diameter (I. D.) of 0.251 inch, 0.282 inch, 0.292inch or 0.376 inch determined by the O.D. of the tubing102. The valve body portion 106 has an 0. D., forexample, of 0.375 inch, 0.402 inch, 0.412 inch or 0.500inch. The machined groove 110 in the valve body portion?WO 98/469241015202530CA 02264091 1999-02-24PCT/US98/06291-9-106 has an I. D., for example, of 0.315 inch, 0.342inch, 0.352 inch, or 0.440 inch.FIG. 5 illustrates an alternate valve bodyextrusion portion generally designated by 106A inaccordance with the present invention. Valve bodyportion 106A includes a conical or tapered wall portion130 for seating engagement with an end 132 of the tubing102. The conical wall portion 130 engages the tubingend 132 to keep the tubing 102 from collapsing.FIG. 6 illustrates a preferred radius grooveFIGS. 7 and 8illustrate alternately configured Vâshaped and squaregrooves 110A and 110B of the valve body extrusionportion 106.configuration for the groove 110.Referring to FIGS. 9 and 10, an alternativegenerally elliptical or inclined groove 140 is machinedin the exterior of the body portion 106. Thealternative inclined groove 140 creates an alternativetubing joint 100A.groove 140 to collapse causing a ramped valve body area142 near the groove 140 to deform together with a tubingarea 144 to achieve a mechanical bond forming the tubingjoint 100A, shown in FIG. 10.An applied force causes the initialReferring to FIGS. 11 and 12, first and secondalternative arrangements of multiple grooves 150 and 152and multiple grooves 154 and 156 are shown. As shown inFIG. 11, grooves 150 and 152 are generally cylindricalformed around the exterior of body portion 106. In FIG.12, a generally elliptical groove 154 is formed at aninclined angle around the exterior of body portion 106.Groove 156 is generally cylindrical formed around theexterior of body portion 106.?WO 98/46924101520253035CA 02264091 1999-02-24PCT/US98/06291-10-Referring to FIGS. 13, 14 and 15, there is shown analternative arrangement for attachment of tubing 102 tothe extrusion body portion 106 including a flangedeyelet 160. The flanged eyelet 160 includes a tubularbody 162 received within tubing 102 and a flanged end164. As best seen in FIG. 14, the O. D. of the tubularbody 162 is approximately equal to the I. D. of tubing102. The flanged end 164 of eyelet 160 is seatedagainst the tubing end 132. The extrusion body portion106 includes a pair of cylindrical grooves 150 and 152defining a tubing joint generally designated by 100B, asshown in FIG. 15. The tubing joint 100B is formed asdescribed above, by applying a force to the grooves 150and 152 with an impact force, crimping or rolling toform deformed areas 174 and 176 of the extrusion bodyportion 106. Deformed areas 174 and 176 of theextrusion body portion 106 form a pair of mechanicalseals at tubing areas 178, 179 to define the tubingjoint 100B. The flanged eyelet 160 provides rigidityfor the tubing joint 100B supporting the tubing 102.with the flanged eyelet 160, tubing 102 can be formed ofa softer aluminum, such as aluminum, grade or typel235F.The flanged eyelet 160 advantageously is formed ofbrass when used with an extrusion body portion 106having a single groove 110 or with multiple grooves,such as grooves 150 and 152 or grooves 154 and 156.Alternatively, the flanged eyelet 160 can be formed ofsteel when used with an extrusion body portion 106including multiple grooves, such as grooves 150 and 152or grooves 154 and 156. An advantage of using steel toform the flanged eyelet 160 is that the eyelet caneasily be detected during processing to determine thatit is properly seated at the tubing end 132.Referring now to FIGS. 16-18, there is shown an?WO 98/46924101520253035CA 02264091 1999-02-24PCT/US98/06291-.11-alternative of the valve body extrusion portion 106 usedin the method for attachment of tubing 102 alsoincluding the flanged eyelet 160. The valve bodyextrusion portion 106 includes an alternative taperedend portion generally designated 180 and a cylindricalgroove 182. Extrusion end portion 180 has a reducedwall thickness. A tubing joint 100C is formed asdescribed above by applying a force to the tapered endportion 180 and the groove 182 with an impact force,crimping or rolling to form deformed areas 184 and 186of the extrusion body portion 106. Deformed areas 184and 186 of the extrusion body portion 106 form a pair ofmechanical seals at tubing areas 188, 189 to define thetubing joint 100C.Referring now to FIGS. 19-21, there is shownanother alternative of the valve body extrusion portion106 used in the method for attachment of tubing 102 alsoincluding the flanged eyelet 160. The valve bodyextrusion portion 106 includes another alternative endportion generally designated 190 and a cylindricalgroove 192. Extrusion end portion 190 includes a cutoutA tubing joint 100D is formed as describedabove by applying a force to the notched end portion 190and the groove 192 with an impact force, crimping orrolling to form deformed areas 194 and 196 of theextrusion body portion 106.portion 193.Deformed areas 194 and 196of the extrusion body portion 106 form a pair ofmechanical seals at tubing areas 198, 199 to define thetubing joint 100D. The notched or square cutout portion193 of the extrusion end portion 190 forming deformedarea 194 closes against the tubing area 198 to preventrotation of the tubing 102.While the present invention has been described withreference to the details of the embodiments of theinvention shown in the drawing, these details are not?CA 02264091 1999-02-24WO 98/46924 PCT/US98/06291-12-intended to limit the scope of the invention as claimedin the appended claims.

Claims

1. A method for attachment of thin wall, small diameter metal tubing to gas valves and other similar gas extrusions having a body, said method comprising the steps of:
providing a body portion having a bore for receiving a small diameter, thin wall metal tube;
forming a groove around the exterior of said body portion;
providing a flanged eyelet having a tubular body and a flanged end, said eyelet tubular body received within said thin wall metal tube with said flanged end seated against an end of said tube; said eyelet tubular body having an outside diameter approximately equal to an inside diameter of said thin wall tube;
inserting said tube and said flanged eyelet in said bore, said tube having an outside diameter less than an inside diameter of said bore: and applying force on said body portion for deforming an area of said body portion near said groove together with said metal tube to achieve a mechanical bond, said mechanical bond providing a gas tight seal.

2. A method for attachment of thin wall, small diameter tubing to gas valves and other similar gas extrusions as recited in claim 1 wherein the step of forming said groove around the exterior of said body portion includes the step of forming a cylindrical groove around the exterior of said body portion; wherein said outside diameter of said body portion is less than about 0.625 inch or about 16 millimeters and wherein each said groove has a depth of about 0.060 inch or about 1.5 millimeters: wherein said outside diameter of said small diameter, thin wall metal tube is less than about 0.5 inch or about 13 millimeters and said small diameter, thin wall metal tube having a set wall thickness of about 0.028 inch or about 0.7 millimeters.

3. A method for attachment of thin wall, small diameter tubing to gas valves and other similar gas extrusions as recited in claim 1 wherein the step of wherein the step of forming said groove around the exterior of said body portion includes the step of forming multiple grooves around the exterior of said body portion includes the step of forming said groove utilizing a selected machining, milling or drilling technique; and wherein said small diameter, thin wall metal tube has a set wall thickness of about about 0.035 inch or about 0.9 millimeters.

4. A method for attachment of thin wall, small diameter tubing to gas valves and other similar gas extrusions as recited in claim 1 wherein the step of applying force on said body portion for deforming said area of said body portion together with said metal tube to achieve said mechanical bond includes the step of applying force longitudinally along the metal tube to a swage member engaging said body portion.

5. A method for attachment of thin wall, small diameter tubing to gas valves and other similar gas extrusions as recited in claim 1 wherein the step of applying force on said body portion for deforming said area of said body portion together with said tube to achieve said mechanical bond includes the step of crimping or rolling said body portion for deforming said area of said body portion together with said metal tube to achieve said mechanical bond.

6. A method for attachment of thin wall, small diameter tubing to gas valves and other similar gas extrusions as recited in claim 1 includes the step of forming said body portion and said metal tube of an aluminum material; and wherein said flanged eyelet is formed of one of steel or brass.

7. A tubing joint for a gas valve or similar gas device comprising:
an extrusion body portion having a bore for receiving a small diameter, thin wall metal tube and an initial groove formed around the exterior of said body portion;
a flanged eyelet having a tubular body and a flanged end, said eyelet tubular body received within said thin wall metal tube with said flanged end seated against an end of said metal tube; said flanged eyelet having an outer diameter approximately equal to an inner diameter of said metal tube;
said small diameter, thin wall metal tube and said flanged eyelet inserted within said bore; and said body portion having at least one deformed area formed near said initial groove to achieve a mechanical bond to said metal tube, said mechanical bond providing a gas tight seal.

8. A tubing joint for a gas valve or similar gas device as recited in claim 15 wherein said extrusion body portion is formed of an aluminum material; and wherein said metal tube is formed of an aluminum material.

9. A tubing joint for a gas valve or similar gas device as recited in claim 7 wherein said extrusion body portion further including a tapered end portion arranged for deforming against said tube.

10. A tubing joint for a gas valve or similar gas device as recited in claim 15 wherein said flanged eyelet is formed of one of brass or steel.