CA2016894A1 - Constant velocity universal joint - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A constant velocity universal joint for transmitting driving torque between rotative members such universal joint including a hub fixed to one of the rotative members and an outer joint member attached to the hub, an inner joint member attached to another one of the rotative members and a ball containing cage positioned between the outer joint member and the inner joint member. The balls are engaged in ball races positioned in the outer joint member and in the inner joint member. The ball races are sloped so as to provide maximum material at the location of highest stress the major ball races being of the undercut free design.

Description

CONSTANT VELQC.ITY UNIVERSAL JOINT
~AÇKGROUNL) OF THE INVENTION ,~
1. Field Qf the Inven _~n The pre~ent invention relates to a constant veloclty universal Joint for use in any applit~atirn requiring tor~ue transmission through a varying angle. More partioularly, the invention involves a universal joint that utili~es a plurality Oe balls to transmit a torque from an inner joint men~her to an outer joint member. The interior of the outer joint member oontains a series of grooves that are in radial alignment with a :
complemelltary series of grouves that are positioned on the exterior of the inner ~olnt memher. A ~flge is positioned between the outer joint member and the inner joint memher to guide the halls as they traverse the grooves during artioulation uf the ulliversal ~oint.

2. Lles~ri~tion of the Prior Art 1~ The prior art revenls a wide variety of deviçes that permit the trnnsmission of a rotntional torque from one shaft that is nngularly dlsplaQed with respeot to another shn~t coupled thereto. In general, most of the prlor art devlc~es require extenslve machilling of the individual parts to assure satiqfac~tory nssemhly and operation of the devic.e. Then, too, the 2C~ overall strellgth of the prior art devioes WAS oompromised by the required maohlning of the indlviduAl palts.
The present invention differs from the underQut-free c.onstant velooity joint that is shown an-l descrihed in U.S. Patent No. 3l3q~,~6C, entitled "Constant Velooity~Joint" issned~April 2~ 75, to Nans-HeinriQh 2s ~ ~ Welsohof et al. The ~onstant veloolty ~jolnt descri~ed in the ~; ` above-referenoed patent ehows nn outer jolnt memher in whlQh the~lndividuAl ;~ ~ ball grooves are divergent with respect to the ~entral axis of the universal ~ joint, wllell viewed from the open end of the outer joint member. The ball :
grooves that are poeltione~ in the inner Joint mqmher are oonvergent wlth respect to the oentral axiY of the un~versal joint. The balls are maintained in a spaQed apart planar relationship with one another hy means ` : : : : : ~ . 1 :

of a cage that is posltiQned hetween the outer joint memher and the inner JQint memher. The Quter join-t memher dQes nQt lend itself to press forging teçhnl~ueY since the opening therein is of Ymaller diameter than the diameter of the interior cavity there.ln. Also, the lip of the outer joint member is thin ber.~ause oE the diver~ent nature of the ball grooves. The thin areAs of the outer joint member occur at one of the areas of maximum stress in the universal Joint, particularly ~hen large angles of articulation are employed.
; : : Thus, the:present invention differs from the a~ove-descrihed : IQ univsrsal Joint in that tbs divergence and convergence of the ball groQVes in the outer Joint mem~er and the inner ~oint meml~er are in reverse order.
Then, too, the Eree end of the outer joint mqmher is of lnc.rease(l thickness in the prese11t inventlon.
In U.S. Pate1lt No. 4,1~ Q3, entitled "~onstant VY100itY
lB Unlversal ~101nt`' issued Fehruary 19, 1.9~0, to Nohuynki Otsuka et al, there i8 shown a universal jOi11t that emp:loys an input and an output shatt. The output stlaft has a cavity contai1ling hub into which is fitted the end of the i11pUt shat. The input YhAt oontai11s an inner member attaohed there~o.
Thq lnside o~ the hub and the outsids of the ioner memher contain ball gruoves. A ball oage is posltioned l~etween the huh and the inner~meml~er.
The hall cage is unique in that itY lnside and outside surfaces contain : ~ : spherioal surfaces that are eccentric instead o the usual concentric sphsrical surfacss. The;ball~cnge is~supportsd on spherical surfaces that are also ecGentric.~
` : 25 ~ The present invention utilizes only concentric ~pherical surEaces whlch~are:easler to for=. ~urther, the~present invention does not have any undercuts that must be made in the huh area as does the ahove reference.
: The hall cage qf~the pre~Pnt invention is quite simple with concentric :: : ~::
: spherical surfaoes bsing s=ployed.:~:Also, the 11Uh and inner torque memhers :; 30 ~utillzs Goncsntrio sphsrlcal surfaces.;

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~ 2 A~ tller example of th& prior art l~ shown in ~.S. Patent No.
4,~10,G4.~, entitled "RQtary Çonstant Veloc~ity Unlversnl Joint" issued Septemher 9, 1'~8~, to Werller Krude. The universal jolnt shown in the patent 4,G10,~43 has nn outer joint member in whiçh the ball groove.~ are convergent : 5 as viewed from the opçn end of the outer joint member ancl the groove~ in the inner joint memher are divergent. This arrangement or slope of the grooves is Just the oppo~ite to that seen in the previously discussed patent ~,~7~,~fiO. The outer joint member is separate frQm the axle-hub combination with which it coacts. A cylindrical ~leeve unites the duter joint member to lQ thç hub hy welding and crimping techniques. A hall çage suppQrting elementis us&d to retain:tbe hall~ in the grooves to engage the hall~ on one sid&.
The hall cag& Yupporting element dQes not contact the spheriGal surfaces of the outer ~oint member or the innYr joint member, but instead, the ball cage contacts a spherical surface 30 in the interior of the Joint near the central hub as stlown in ~igurç 1, In the ahove-clescribed patent, the ball cnge contains a serle~ of ringers that are intercnlated with respect to the balls. This universal Joint requires &xt&nsive machining to fahricflte tlle ~oint as well as oomplicnted toQls for fnhriGntlng the varions details.
The present invention is nn improvement over tlle universnl joint ~0 shown and descrihed in the patent 4,~10,~4.~, ln that fewer p~rt~ nre : utllized and there is less:friotional contact with the ~all cage.
Additionnlly, the prt-se.nt invention provicles a ~all Gage with apertures therein that compIetely circumscrihe~ each ball. Purther, by pro~viding a universAI Joint with an outer ~olnt membe~r having a thick struGtural seGtion ~; 25 ~ near~lt= open end, the~area of highest load contentration upon artit~ulatlon, : ~ th&~oint 1~ more reliahle and:durahle. ~The nuter joint member fahricatiQn is simplified and the Gost~ of fahri~ation is signifiGantly reduced.
SllMMARY OF THE PRESENT INVENTION~ ~
The present invention:is a Gonstant~velocity universal joint for : ~0 use in transmitting a:driving torque from a first axial direGtion to another axial direGtion,~angularly r.lisyr)sed wllh respect to the i`ir~t direction.

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The present invention relates to a torsiGnally elastic shaft coupling consisting of two coupling elements, namely a hub element with means to provide a rigid connection to one of two shafts that are to be joined together so as to prevent independent rotation, and a driver element that for its part comprises essentially two carrier plates that incorporate means to provide a connection to the second of the two shafts that are to be connected to each other and which enclose between themselves at least one cage in which, in each lo instance, between at least one driver or a stop of each of the two coupling elements there is at least one rubber shock-absorbing element. ~

Known couplings of this type incorporate stop elements that engage one behind the other in the direction of rotation of the two coupling elements, with rubber buffers interposed between these elements in order to produce the required torsional elasticity. 'rhese rubber buffers are solid rubber blocks with dimensions that are relatively small in comparison to the dimenslons of the couplings, so that they can be loaded by the stops of the coupling elements, which ,'jl~
can he twisted against eich other, exclusively in compression and/or tension, at least~;essentially.
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The working range of these couplings is characterized by extremely small angles of rotation. In addition, as a rule, couplings such as these~are extremely noisy, i.e., sound waves pass practically ushindered from one to the other of the two shafts that are ~o be connected with each other when they are in contact. ,~ ~
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It is an object of the present invention to so improve a torsionally elastic shaft coupling of the type described in the introduction hereto,il~such that large angles of rotation are used with soft characteristic curvesj and at the same time the input shaft and;,-the output sha~t can be accoustically decoupled.~

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~RIE~ D~S~.RIPTION 0~ THE ~RAWIN~S
Fig~lre lA is a part sec~tiQnal view of A prior art undercut-free outer Jolnt member and a graphical representation of the prior art under-cut free collstant velocity Joint forces experienced in the hall track as the hending angle increases Figure 1 is a part ~eçtioned side vlew that shows the UlliVerS
~olnt of the present inventlon, Figure 2 i9 a part seGtioned side view that shows the universal jolnt in an angular drive attitude:
lQ Figllre 3 is a part sectioned side elevational view of the integral huh and output shaft;
Figure 4 i8 an end vlew of the hub and output shaft as viewed along lines 4-4 of Figure ~;
Figure 5 iY an elevational end view of the outer joint memher that 1~ shQws the pairs of grooves positiQned on the interior surface thereof;
Figure 6 is a seotioned vlew takell along seotlQn lines 6-6 of Figure fi wllioh shows the qurvilinear surPnoes for the halls and the oage;
~'igure 7 is an end view of the inner JQint member that shows the pairs of grooves positione-.l on the exterior surface of the inner ~oint member; and Figure 8 is a seçtiolled vlew taken along sectioll lines 8-8 of Fleure 7 that shows tbe ourvilinenr surfaces for the balls nnd the cage.
It is to;be understood that~the~present invention ls not limited to the details of c.onstruçtion and arrangement of parts lllustrated in the acobmpanylng drawings, since the invention is capable of other embodiments and of being practiced or çarried out~in various ways within the sçope of the Glaims. Also, it is to be understQod that the phraseology and ter~ln~logy employed herein ls for:the~purpose of description and not of llmitation.
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DETAILE~ PTION OF THE PREFERRED EMBODIM~NT
Keferring to the rIrnwings and more partioularIy to Figure lA, there i9 illu~trated a prior art underçut-free çonstant veloçity univers~l ~Oillt in part seçtion view that hflS app1icatIon for mnny uses such as the 6 çoupling of drive shaft.s and other appliçations. The graph illustrated therei-l represents the forçes experienced in the outer JoInt member as the hendlng angIe inçreases. The hendlng is the angle of artiçulation between the çelltra1 axis of the out~r ~oint member and the çentral axis of the inner : ~oint memher. The graph o1early shows that the greatest forçes nreexperienoed at mnximum ~ending angle and in the area neal the opel~ en~l uf the outer ~oint memher. ~ :
Figllre 1 is a part seçtioned side elevational view that shows the universa~l ~oint of the present lnven-tion. The overall apparatus is identified by the llumeral 10 as shown.` For purposes:of illustration it will he nssumed that n rotational forçe or torqne is npplled to nn input shaft 12 WhiCIl iY sllcwn nt the rlght-llalld side of Figure 1. An output shnft 14 is pQsitiQnecl at the left-llnlld side of the overall apparatus:10. Of oourse, tlle flow o.~ torque ~ould he in a direotion oppos1te;to that nhove stated.
The output sha~t 14 i3 ooup1ed to a huh:16 that çan ~e, as shoan, an integral part of the output shaft 14.: Tlle huh 16 and the output:shaft 14 ; : are ooaxial along an output axls 20. An input~axls 18 1s shown çolnoldental : wltil the output axls 20. The~hub~l6~hss a cylisdrlçnl sxternal surfsoe 2a thnt nhuts a radinlly inwar~ lip 24. ~The~lip 24 i;s plannr and is psrpsndlcular to ths output ssls~20.~ The hub 16 hss a~ooncsvity tbat is as~ formed by an arouate seGtion~26, a:frus~toooniça1~ssQtlon 26, and a sphe.riçal seoti~on 30. The blend:ine together~oÇ~tlle~above~three ssotions produçes a çoncavlty~thst can~he~resdlly for~ed~by prsss snd forge~teohniq-les~.
` An ~uter joint me~her ~2 has~an exterior~surface 34 that is dylindriçal~about~ths~output~ axis~:20.~Ths left-hanû:end of the:outer ~oint 30: member~32, as~vie~ed in P'igur~e~ ;1las~an~ terna1~oy1Indr~ica1 surfnoe 36 of shorter radius than the exterior~surfsçe 34. ~The internal çyllndriçal :
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~urfaoe 36 of the outer joint member 32 ooaots with the cylindrical external surface 22 of the hub 1~ ln or-.ter to çquple the hllh 16 and the outer ~oint memher 32 ln n manner to he more ~ully desçribed hereinafter. The outer joint memher 32 hax nn interior ~pherical surfaçe 38. The lnterior spherical surface .~ i9 defined hy a radius that hns its locus situated on the input AXi~ 18 a~ a point L. The left-hand end 40 of the o~lter ~oint member 32 i9 planar In configuration and has a radIal extent xpanning the distanGe between the internal cylindricnl .qurfaoe 3~ and the lnterior spllerlcnl surfaoe 3$~. The junctllre between the end 40 and the interior spherical surface ~8 can he heveled as identified hy the numher 42. The right-hand end 44 of the outer joint memher 32 hax a planar configuration ` and has a radial extent that extend~ hetween the exterior surfaçe 34 and the interior splIerical surface ~8~ The ~uncture between the end 44 and the interior spheriqAl surfaçe 3~ ix heveled at approximately 45 as will he oommented on elYewhere. ThUY, lt is evident that a laree cavity paxsex through the cqntral axial region of the outqr ~oint meml~er 32 A plura.llty of axially exteo~ g nrouate ball races or grooves 4~
is cut into and tllrougll the interior spberiçal ~urfaoe a8 of the outer joint member ~2. The mid line or the most radially outward extent of each ball rnce has a cir-ular Yeçtion 48 that i8 çoupled to an essentlally linear : section 50~ The oircular seotlo!I 48 haY a radiux with a loçuY that iY
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posItlonFd on the output~axix 20 to the left nf the:~polnt L. The ball raçes 46 are positione~ diametrically wlth rexpeot~to~:enoh other as is shown ln Figure 5. Each pair of diametrically oppQ~ed hall raoes~4~has their mid ~: 25~ ;llnes 1ying in a plans that also~contains:ths;~output axis æo. ~ ~
An inner~oint:msmhsr~62 is posi~tioned witbin the open cavity that : passes through tbe OUtRr joint~member~92.~ The lnner ~olnt member 52 i9 po~itioned xymmetrioally ahout the input:axis 18.: The inner ~oint memher 62 as an internal oylindrical~hore 54 tlIat 19 equippe~ with axi~lly extending : :~ 30 :~ splines 56. The Innsr ~oint -ember~;52~has~r~adia~11y sxtending left and right-hand eYsentially planar~ends 5~and 60. ;The most radial exterior : 7 ~: :
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surfnce fi2 uf the inrler ~Oillt ~ember 52 is spherical in cullfiguration with the sphericnl extent ternllnating at thç ~uncture with the planar en-ls 58 and .
The inner ~oint memher 52 contains a plurality oE axinlly extending arcuate bnll races or grooves ~4 that are çut into and through the exterior spherical sur~ace ~2 The mid line or the must radial inward extent of each hall race fi4 has a circular section fi~ that is oonnect.ed to an essentially linear section 68. The circular section ~e llas a radius with a locus that is positioned on the inpu-t axls 18 to the rlght of the point L.
1n The distance o~ the locus of the circular section 6~ ~rom the point L should ~e essentially equal to the distnnce of the locus of the circular ~ection 48 of tlle outer ~oint member from the poin-t L
A hall cage 70 is positiuned within the cnvity of the outer joint memher 32 nnd i~ ~paced éxteriorly of the inner Joint meml~er 52 in 1~ tele~ooped arrallgement. The hall qage 70 has çxterior and interior spllerlcal surfaue~ 72 antl 74 thal are toorlcentrio wlth une another. The exterior ~pherioal sur~ace 72 is ternlinated at lts left-han-l end a~ viewed in Figure 1 by a radlally lnwardly extending end 76 The most radially ~ inward portion of -the end 7ff lntersects an axlally extending cylindrical ; 20 l~ore 78. ThR cylindrioal hore terminntes at its right-hand end with nn interseQtiQn aith the interior spherioal surface 74. The exterior spherical surface 72 of the hnll cage 7n~terminate~ at its right-hand end by a radially in~ardly~extending end 8Q. ~The most radially inwnrd portion of the end 80 lnterseQts all axially extending oylindrical bore 82. The cylindrical 25~ bore 82 terminntes at its le~ft~-hand end wlth an intersectioll with the interlor~sphericnl surface~q4.~
The exterior~spherical ~urface~q2 of the ball cage q~ is in rotn~ionai contnot with the interior sphericnl surfnce 38 of the outer ~oint member 32. In a similar mnnner~ the interior spherioal surface 74 of the ball cag~ q0 i~ in rotational contact with the exteriQr spherical surface 62 of the~inner Joint member S2.~

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A plurality of radially qxtenr.1ing l~ores or win~10ws 84 is positioned in the wall creat.ed,hy the exterior and interior spherical surîaees 72 and 74 of tlle hall cage 70. The axes of the bores ~4 pass through the point L on the input shaft 12. Each axls B4 is colnoident with the mid llne of the l~all races 4~ and 64. In other words, the axis of each hore ~4 lies in a plane that. çontains the mid lines of eaçh pair of mid lines a~sQcisted with the ball races 46 and &4.
: A sphericnl:hall ~6 is~ posl~tioned within the confinement of eac,h hore ~4 90 that it can translate ~slmultaneousIy along the mid lines of the ~ball races~ ~6 and 64.
The input shaft 12 has externally protrudil1g splines ~8 that mesh with the splines 5& that extend axially alQng the cylindrioal hore 54 of the inner joint melnl~er 52.
The aylindr.taal Lore 54 of the inner ~oint member ~2 contains a lo reentrant groove sn for the oontninment of a fingerloak retaining ring ~2.
pll~rallty of cantilevere~ resllient fingers ~4 snap over a radially disposed ledge ~q thnt qlrollmsarihes the input shaft 12. Thus, the fingerlock retainlng ring ~12 prevents axial movement of -the input shaft ~12 with respect to the inner ~olnt member 62.
Figure 2 is a part sectioned side view of the overall apparatus 10 that shows the~ u1llversal Joint in an sngul~sr drive attltude. For~purposes of discussion, the output shaft 14,:the attached hub 16~:and the oute,r~joint memhsr 32 rem~ in ~Ixed relstlonshlp~to~one ~no~ther :and~da not ~move, other thàn~;rotstlvsly. As dsp~cted~ ln~FIgurs~ 2, ~ths 1nput ~sha~t 12 hss sssumed a `25~ ;positlon sa:thst its: input~aK;ls i~ is sngularly~dlsposed~wlth respeot to the output axls 20 of the autput shaf~t~; 14~ As;~ the input shaft 12 moves to a new: anguiar positian, the~inner;jo~int memher~2 also movss~through the sam~
angle:since it is flxed with rsspect~ to the inp~1t shsft 12. As the inFut shsft~12 moves through a:given;sngls~, the spherical halls 86 t~Anslate alcng 30 ~ ~the most ;vertioally orl~ente~d~spherlosl~ball ~6 moves the furthest to the right while the lowest: diametrioal~ly pasltioned spherical hall ~& moves `: ~ ` :

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çorrespolldillgly to thç left along anrther pair of ball racçs 46 and 64. The renlnining spherlral halls ~ move corresponrlingly along the ball races 4B
and ~4 C)f ~ourse, if a pair of spherlccll halls ~ lies on the input axis l~, there would he no translatloll along the hall races 4~ and ~4 The ahove discussion assumes that there i9 110 rotation of the input and output sll~ts 12 anrl 14 As the inFot shart 12 and the inner Joint member 52 articulate through a given angle, the ball cage 70 rotate~ a lesser amount as ran be seerl in Figure 2 It is important that the ball cage 70 always articulate~
so that the nxls ~ of the hores ~4 remains posltloned so that the pQlnt 1 lies thereon, In thls nlanner, a nonstant velocity will be achieved through the overall appAratus 10.
Arl examination of the lower sphericnl hall ~6 in Figure 2 shows that lt has moved to the let until it is in close proximlty to the arçuate sectirn 2~ Or the hub 1~ Alsu, the lowermost purtion of the hall cage 7Q
has moved to the left untll lt ocr.uples part of the ravity defined by the frustoconloal seotion 2~ The hnll c~ge 70 hns contact Wit}l only the spherioal halls ~6, the interior spherlcal surEAce .~ of the outer ~olnt memher 32, and the exterior spherioal surfar.~e 72 of the inner joint member The angulAr movement r~f~the input shart 12 is terminated when the input shat 12 rcontarts a rustQr~onical heveled~surfare 100 of the outer Jolnt nlember 32.
Figure 3 is a part ser~tloned side elevational view of the integral ~25 huh l~ and the output shart 14 The output~hart 14 can he divided in-to cyllndrical axial extents;102 and~104, each containing an arcuate array of longltudinally aligned splines~106.~ The hub 16, whlch is an extension ~f the output shaft 14, has An lnternal cavity defined by the arcuate section 26, the Erustooonical section~2~,;nnd the spherical seçticn .~0. Since ther~
~0 is no undercutting required in the for~ation of the internal ~avity of the : ~ :
hub 1~, lt can be formed hy pres~ or forging techniQues.
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Figurq 4 is an end view of the huh cavity as viewed along lines 4-4 of ~igure 3. The lip 24 is shown in its planar view along with the lines of intersectioll be~ween the prevlously mentione-.i surfaces of the cavity within thq huh 16.
Figllre 5 i9 an elevatiollal end vlew of the outer joint memher 32 that shows the dinmetriçally opposed pairs of grooves positione-l on the irlterior spherical surface 38 of the outer Joint member ~2. As can be seen, : the hall races 46 are not undercut; thus, they can he formed by pre~s or forge teohniques. If sinterlng teclmi~ques are employe~ in the fabrication of the outer ~oint memher 32 tùen metfll removal teohniques need not be employed to form the spllerical lnterior surface 38. The cross-seotlonal configurntlon of the I~all race 4fi~is shown as oircular with tangential pnr.nllel extensiolls 10~ coupled theretcI. Whlle the extenslons 108 are shown as parallel, they may, iE desired, diverge slightly toward -the inpu~ axis 18. Al80, the arcuate c~ross-sectional portiolI of the ball raoe 4fi cnn he ~lightly non-r~ircular, provid.lng for line çontact with the spherical bnlls tlla~t translate theretlIro~lgll. ~
Flg~Ire fi 19 a ~ectional view taken along sectlon lines fi-6 of Flgure ~ ttlat shows the curvillnear surfaoe of the ciroular and linear 2Q sections 48 and 6Q. The inlerior spherlQal surface 38 is also shown.
~ Figure 7 i9 an ~nd view of the inner joint memher ~2 that shows : :: tlIe pairs of cilametrically:cppc)sed ball races ~4::positioned on the exterior spherical sur~façe~fi2~o~ the Inner jolnt~member 52. The nMmber of ball raoes ; fi4 Rquals~the number of ball:races 48 as previously~shown in Figure 5. The 25: ~ oyllndrlcal bore 54 contnlns~t~he~s~plines 5fi:whloh are~ln~axial allgnment :with the~input axis 18.
: Flgure 8 Is a secti~lnal view;;taken~along~sectlon liDes ;2-8~of Fig~Ire 7~that shows the curvll~lnear mid~llne of the~:bail raoe~fi4 and~the exterior:spherical surface 62 of the:inrler~oin:t member:52. The planar left ; 30 ~and right ends~58 and BO~pelmlt~the~èmployment of sasg~fabrlratlon tscl~lniques as prsvlously oo-mented on.~

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ASSEMRLY AN~ OP~RATI~.)N
The assembly uf lhe overall apparatus 10 cf the present invention is very straightfr)rward. Also, the geometry rf the components of the overall apparatu~ 10 permit automated a~sembly. The lnner ~oint member .52 .5 is positioned 90 that Its left-hand edge, as viewed in ~ig~1re l, is facing up. Next, the hall r,age 7n ls lowered conce11tri~ally, and in axial alignment, arqund the lnner joint memher 62 until the bores a4 are opposite the c.lrc.ular sectio~ of the ball race ~4. The spherir,al balls a6 are : then in~erted into each of the boies 84.: As the spherir,ll balls 86 move radlally inwarll, they will contact the circular sec.tlon ~6 of the ball race 64 and remain stntionary. The outer joint memher ~2 is then telesooped over the hall onge 70. The ball oage 70 is then moved into final axial alignment. The spherioal halls a~ are now held against rarlially outward disengagemel1t L1y the hall races 46. The cylindrical external surfac.e 22 of 16 the hub 16 i9 then m-ve-.1 lnto engngen~ent with the internal r.yllnrlrical surfaoe 3~ Or the outer Jolnt member 32 and the11 imlnobili~ed therewit}lln.
The immohillzatlon teohl1lque onn involv~ a press fit, welrling, or a snap ring placeme11t ns depioted nt 10an in Flgure 2. At this tlme or subsequent thereto, the input shaft 12 can he inserted into the oylindrical bore 54 so that the splines 56 and aa slide into sngagemsnt. Upon full insertlon of : ~ the input shaft l2, the resilient fingers:~4 oE the previously inserted retalning ring ~2 engage with the ledge 96:on the input shaft 12, looking it into~its final positlon.
During operation o~ the overall:~apparatus 10, a torque is applied 2~ : to the input sha~:~ 12, causing it ànd th~spIine coupled inner joint mem~er 52~to rotate.: The torque~is then transmittqd from the inner joint mem~er 52 to the spheri~al balls a~ by oontaçt~wl~th the hall races ~4. The spherical : : halls ~6 then transmit the torque to the outer joint n~ember 32 via the ball races 46. ~5ince the outer joint member i~s non-rotatlvely at-tached to thç
~`` 30 : lip 24 of the hub 16, the hub 16:rotstes along with the integrally attac}1ed : output shaft 14.
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Whell the input and output axis 1~ and 20, respectively, are in alignmellt wlth one another, the spheriçal balls ~fi will remain at one location along the i~all races 46 and ~4 during rota~ion of the overall apparatus 1~ Sinçe the spheriçal balls are centrally positioned ~1ithin the hall raçes 46 and 64, the stresses are fairly well distrihuted through the outer joint memher ~2 an-l thq inner jolnt member .~2 As the input shaft 12 anrl its accompanying input axis 1~ assume an angular position or bendillg angle, such as 45a, with reapec-t to the output shaft l4 nnd its output axis 20, the spherical halls 86 no longer traçk in a In single cirçular pati- ahout the lnput axis 1~ Doring one complete revolution of the overall apparatus 10, the spheriQal halls ~6 will traverse nearly -the entire length of the ball raçes 46 and 64 Since the spheriçnl halls ~6 are fixed against laternl movement with respeçt to tbe hall oage 70, tbe hall cage 70 not only rotate~ on its exterlor and interior spherical l~ surfaoes 72 ~nd 74 h~t, also, the hall oage must rotate when thR input axis 1~ shlfts pQsltion from lert to right nbout an axis that passes through the pOillt L The rotntional axis for the hall oage 70 i~ perpendiçular to the inpul~ axis 1~ ollly whell ~he input and output axes 1~ and 20 are in alignment The amount and frequenoy of the rotation of the hall oage 70 al~out it~ axis depends on the frequenoy and magnitude~of the rhange in -the angle as identified in Figure 2 hy referençe numeral 110 When the overall apparatus 10 i9 operating~at a maxlmum~bending angle, a maximum load oçours against the inslde surfaçe of the çlrçular ieotion 48 adjaçent to the end 44 of~the outer ~oint member 32.~ This~point~of maximum load iY identified by 25~ numeral lI2 In Figure 2 Since the~design of the outer ~o~int memher ~2 isthiokest~at the end 94, it çan~withstalld~`~the high loads indnced at the maximum load p~int 112 Then,~ too,~the~inçreased ovqrall çross-seçtiQn of the outer jOillt~ member 32 nt the end~44;reduces the~amoorlt of deteçtion of the end 44 in a cirçumferential or hoop~direçtion The reduoed cironmfersntlal elongation results~ln longsr lifs and increased durahility of the overall apparatus ~ 13 ::

While the illustrcltive emhodimellt of the invention has been descrihed in oonsiderable letail for the purpsse of setting fqrth a practical operative strllcture wherehy the 1nventioll may he pr~sticed, it is tn he understqo-l that the partic.ular apparatus descrlbed is intende~ to be illostrative only, and that the various novel characteristic~ of the invention may be IncorporAted in sther s-tructur~l ~orms withollt departing fr-.m the spirlt and scope of the invention defined in the appended claims.
~ ~ hat is F~a~ed i8- ~

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Claims (30)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A constant velocity universal joint for use between two shafts for transmission of power from a driving shaft to a driven shaft comprising:
an inner join member having an exterior spherical surface, an axis of symmetry and an aperture located about said axis of symmetry;
drive means positioned within said aperture to facilitate rotation of said inner joint member;
a first plurality of axially aligned ball races formed in said exterior spherical surface of said inner join member;
an outer joint member having one end, an interior spherical surface, and a centrally positioned aperture therethrough, said outer joint member being positioned in telescoped concentric relationship with respect to said inner joint member, said outer joint member further having a centrally positioned axis therethrough;
a second plurality of ball races formed in said interior spherical surface of said inner joint member;
a plurality of spherical balls interposed said inner joint member and outer joint member;
containment means interposed between said inner joint member and said outer joint member for the containment of said plurality of spherical balls, each ball of said plurality of spherical balls being in contact with said first and second plurality of ball races;
a hub attached to said one end of said outer joint member, said hub having a centrally positioned cavity therein; and an output shaft formed as an integral part of said hub, said output shaft having an axis coincident with said centrally positioned axis of said outer joint member,

2. The constant velocity universal joint of Claim 1 wherein said drive means comprises an input shaft, said input shaft comprising a plurality of splines on one end thereof.

3. The constant velocity universal joint of Claim 2 wherein said drive means further comprises a plurality of splines positioned within said aperture of said inner joint member.

4. The constant velocity universal joint of Claim 1 wherein said containment means interposed between said inner joint member and said outer joint member is an apertured ball cage.

5. The constant velocity universal joint of Claim 1 wherein said containment means comprises an annular cage member having an outer surface, an inner surface spaced from said outer surface, a centrally positioned aperture having a central axis, and a plurality of circumferentially spaced radially aligned apertures interposed said inner and outer surfaces for the containment of said spherical balls.

6. The constant velocity universal joint of Claim 5 wherein said plurality of circumferentially spaced radially aligned apertures are of an even number.

7. The constant velocity universal joint of Claim 6 wherein said plurality of circumferentially spaced radially aligned apertures are arranged in diametrically opposite pairs perpendicular to said central axis of said centrally positioned aperture.

8. The constant velocity universal joint of Claim 7 wherein each of said apertures of said plurality of circumferentially spaced radially aligned apertures contains one of said spherical ball.

9. The constant velocity universal joint of Claim 8 wherein said outer surface of said annular cage member is an exterior spherical surface and further wherein said inner surface of said annular cage member is an interior spherical surface, said interior and exterior spherical surfaces being concentric with one another.

10. The constant velocity universal joint of Claim 1 wherein said first plurality of ball races in said inner joint member have a minimum radial distance from said axis of said inner joint member adjacent to said hub.

11. The constant velocity universal joint of Claim 10 wherein each of said first plurality of ball races are comprised of a curved section and a linear section.

12. The constant velocity universal joint of Claim 1 wherein said second plurality of ball races in said outer joint member have a maximum radial distance from said axis of said outer joint member adjacent to said hub.

13. The constant velocity universal joint of Claim 12 wherein each of said second plurality of ball races are comprised of a curved section and a linear section.

14. The constant velocity universal joint of Claim 1 wherein said exterior spherical surface of said inner joint member is of greater radial extent from said axis of said inner joint member than said first plurality of ball races contained therein, and said interior spherical surface of said outer joint member is of lesser radial extent from said axis of said outer joint member than said first plurality of ball races contained therein.

15. The constant velocity universal joint of Claim 14 wherein said exterior spherical surface and said interior spherical surface are concentric with one another.

16. A constant velocity universal joint for use between two shafts for transmission of power from a driving shaft to a driven shaft comprising:
an inner joint member having an axis of symmetry, an exterior spherical surface, a central splined aperture located about said axis, and a first plurality of axially aligned ball races formed in said exterior spherical surface; said exterior spherical surface being of greater radial extent from said axis than said plurality of axially aligned ball races;
an input shaft, said input shaft having a plurality of splines positioned within said central splined aperture of said inner joint member, said plurality of splines being oriented parallel to an axis of said input shaft;
an outer joint member, said outer joint member having one end, an interior spherical surface, and a centrally positioned aperture therethrough, said outer joint member being positioned in telescoped concentric relationship with respect to said inner joint member, said outer joint member further having a second plurality of ball races formed in said interior spherical surface and a central axis therethrough, said interior spherical surface being of lesser radial extent from said central axis than said plurality of ball races;
an annular ball cage member interposed between said inner joint member and said outer joint member for the containment of a plurality of spherical balls, said annular ball cage member having an outer surface, an inner surface spaced from said outer surface, a centrally positioned aperture, and a plurality of circumferentially spaced radially aligned apertures between said inner and outer surfaces for receiving one each of said spherical balls, said plurality of spherical balls each being in contact with said first and second plurality of ball races;
a hub attached to one end of said outer joint member, said hub having a centrally positioned cavity therein; and an output shaft formed as an integral part of said hub, said output shaft having an axis coincident with said axis of said outer joint member.

17. The constant velocity universal joint of Claim 16 wherein said plurality of circumferentially spaced apertures in said annular ball cage member are of an even number.

18. The constant velocity universal joint of Claim 17 wherein said plurality of circumferentially spaced apertures are arranged in diametrically opposite pairs perpendicular to said axis of said centrally positioned aperture.

19. The constant velocity universal joint of Claim 16 wherein said annular ball cage member has interior and exterior spherical surfaces that are concentric with one another.

20. The constant velocity universal joint of Claim 16 wherein said first plurality of ball races in said inner joint member have a minimum radial distance from said axis of said inner joint member and further wherein said first plurality of ball races are comprised of a curved section and a linear section.

21. The constant velocity universal joint of Claim 16 wherein said second plurality of ball races in said outer joint member have a maximum radial distance from said central axis of said outer joint member and further wherein said second plurality of ball races are comprised of a curved section and a linear section.

22. The constant velocity universal joint of Claim 16 wherein said exterior spherical surface of said inner joint member and said interior spherical surface of said outer joint member are concentric with each other.

23. The constant velocity universal joint of Claim 16 wherein said hub and said outer joint member are united by a snap ring.

24. The constant velocity universal joint of Claim 16 wherein said outer joint member has a greater wall thickness on an opposite end most remote from said hub.

25. The constant velocity universal joint of Claim 16 wherein a retaining ring is interposed between said inner joint member and said input shaft.

26. A constant velocity universal joint for use between two shafts for transmission of power from a driving shaft to a driven shaft comprising:
an inner joint member, an exterior spherical surface having an axis of symmetry, a central splined aperture located about said axis, and a first plurality of axially aligned ball races formed in said exterior spherical surface, said first plurality of ball races having a minimum radial distance from said axis of symmetry, said first plurality of ball races being comprised of curved and linear sections, said exterior spherical surface of said inner joint member being of greater radial extent from said axis than said first plurality of ball races;

an input shaft, said input shaft having a plurality of splines positioned within said central splined aperture of said inner joint member, said plurality of splines being oriented parallel to an axis of said input shaft;
an outer joint member having one end, an interior spherical surface and a centrally positioned aperture therethrough, said outer joint member being positioned in telescoped concentric relationship with respect to said inner joint member, said outer joint member further having a centrally positioned axis, a second plurality of ball races formed in said interior spherical surface, said second plurality of ball races having a maximum radial distance from said central axis, said second plurality of ball races being comprised of curved and linear sections, said outer joint member further having a greater wall thickness on an opposite end, said interior spherical surface being of lesser radial extent from said central axis than said second plurality of ball races;
an annular ball cage member interposed between said inner joint member and said outer joint member for the containment of a plurality of spherical balls, said annular ball cage member comprising an outer surface, an inner surface spaced from said outer surface, a centrally positioned aperture, and a plurality of circumferentially spaced radially aligned apertures of even number arranged in diametrically opposite pairs perpendicular to said central axis, said plurality of circumferentially spaced apertures each containing a spherical ball, each said spherical ball being in contact with said first and second plurality of ball races of said inner joint member and said outer joint member, respectively, said outer surface and said inner surface of said annular ball cage member being spherical surfaces that are concentric with one another;
a hub attached to said one end of said outer joint member, said hub having a centrally positioned cavity therein; and an output shaft formed as an integral part of said hub, said output shaft having an axis coincident with said axis of said outer joint member.

27. The constant velocity universal joint of Claim 26 wherein said exterior spherical surface of said inner joint member and said interior spherical surface of said outer joint member are concentric with each other.

28. The constant velocity universal joint of Claim 26 wherein said hub and said outer joint member are united by a snap ring.

29. The constant velocity universal joint of Claim 26 further comprising a retaining ring interposed between said inner joint member and said input shaft for mounting said inner joint member to said input shaft.

30. The constant velocity universal joint of Claim 26 wherein said output shaft has a plurality of spline sets on one end thereof, each spline set having splines circumferentially spaced apart and in axial alignment with said axis of said output shaft.