CA2385717C - Speed-difference-dependent hydraulic clutch with control valves - Google Patents
Speed-difference-dependent hydraulic clutch with control valves Download PDFInfo
- Publication number
- CA2385717C CA2385717C CA002385717A CA2385717A CA2385717C CA 2385717 C CA2385717 C CA 2385717C CA 002385717 A CA002385717 A CA 002385717A CA 2385717 A CA2385717 A CA 2385717A CA 2385717 C CA2385717 C CA 2385717C
- Authority
- CA
- Canada
- Prior art keywords
- speed
- difference
- clutch
- opening
- control valve
- Prior art date
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- Expired - Fee Related
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- 230000001419 dependent effect Effects 0.000 title claims abstract description 12
- 238000006073 displacement reaction Methods 0.000 claims abstract description 28
- 230000002706 hydrostatic effect Effects 0.000 claims abstract description 8
- 230000009471 action Effects 0.000 claims abstract description 7
- 239000012530 fluid Substances 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 3
- 230000006978 adaptation Effects 0.000 abstract 1
- 230000004044 response Effects 0.000 description 3
- MWRBNPKJOOWZPW-GPADLTIESA-N 1,2-di-[(9E)-octadecenoyl]-sn-glycero-3-phosphoethanolamine Chemical compound CCCCCCCC\C=C\CCCCCCCC(=O)OC[C@H](COP(O)(=O)OCCN)OC(=O)CCCCCCC\C=C\CCCCCCCC MWRBNPKJOOWZPW-GPADLTIESA-N 0.000 description 1
- 102000004726 Connectin Human genes 0.000 description 1
- 108010002947 Connectin Proteins 0.000 description 1
- 241000155250 Iole Species 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000009365 direct transmission Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D25/00—Fluid-actuated clutches
- F16D25/06—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch
- F16D25/062—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch the clutch having friction surfaces
- F16D25/063—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch the clutch having friction surfaces with clutch members exclusively moving axially
- F16D25/0635—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch the clutch having friction surfaces with clutch members exclusively moving axially with flat friction surfaces, e.g. discs
- F16D25/0638—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch the clutch having friction surfaces with clutch members exclusively moving axially with flat friction surfaces, e.g. discs with more than two discs, e.g. multiple lamellae
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D43/00—Automatic clutches
- F16D43/28—Automatic clutches actuated by fluid pressure
- F16D43/284—Automatic clutches actuated by fluid pressure controlled by angular speed
Abstract
A speed-difference-dependent hydraulic clutch comprises a drive housing (27), which rotates in a housing (25) that is fixed in space and forms a reservoir, a hydrostatic displacement machine (35), an output shaft (30), a friction clutch (36) and a piston (5) for acting on the friction clutch (36), a pressure being produced in a pressure chamber (4) when a difference occurs between the speed of the drive housing (27) and that of the output shaft (30), this pressure giving rise to action upon the friction clutch (36).
To achieve rapid control and adaptation of the characteristic, the first and the second opening (9, 10) are each connected to the reservoir (8), via a first and second rotary input (13, 14) and a first and second controllable control valve (15, 16) respectively, said valves being fixed to the housing, the first and second control valve (15, 16) being designed as controllable throttles, with the result that a control action takes place both at the respective supply side and at the discharge side of the displacement machine, irrespective of the direction of the differential speed.
To achieve rapid control and adaptation of the characteristic, the first and the second opening (9, 10) are each connected to the reservoir (8), via a first and second rotary input (13, 14) and a first and second controllable control valve (15, 16) respectively, said valves being fixed to the housing, the first and second control valve (15, 16) being designed as controllable throttles, with the result that a control action takes place both at the respective supply side and at the discharge side of the displacement machine, irrespective of the direction of the differential speed.
Description
SPEI D D![ FERENC'E. DEPE.NI)EN"1 HYDRAULIC CLUTCH WIT1i CONTROL.
VALVES
The invention relates to a speed-difference-dependent hydraulic clutch, comprising a drive housing, which rotates in a housing that is fixed in space and fon-ns a i-eservoir for a working fluid, a hydrostatic displacement machine, wliich is accommodated in said drive housing, a drive shaft, a friction clt-tch for connecting the drive shaft to the drive housing and a piston for actin- on the friction clutch, a pt-essure being produced in a pressui-e space when a difference occurs between the speed of the drive housing and that of the drive shaft, this pressure giving rise to action upon the fi-iction clutch, and the hydt-ostatic displacement machine havin~.; a first and a second opening for the supply and discharge of working medium and a third and fourtlz opening for connection to the pressure chamber.
Clutches of tliis kinci are uscd in various configLn-ations in the drive train of motor vehicles foi- direct transmission of a torque or locking a linked differential for the puIpose of driving the wheels on one axle ot- distributing the drive torque between two axles. The hydrostatic displacement machine comprises an inner rotor and an outer rotor, foi- example, but it is equally possible 10 use liydi-ostatic displacement machines of some othet- kind. In eitller case, two parts (c.t;. the drive housing and the otitput shaft) perform a i-clative motion when there is a speed diffei-ence and thus produce a pressure that acts on thc piston of the li-iction clutch.
A clutcll ot thls klnd is ktlown, for exatnple, fi-oni US-A 5,536,215. ]n this, a valve formed by a bII1lCtallic Iral'is provided between the pt-essure space and a space at low pressure, tlie clutch space, tllis v~ilvc hcin,~:,N intended to compensate for temperature-deheildcnt changes in tlle viscositv of tllc working fluid. Therc are no tiirther control 111cn1I)Crs.
- ~ -US 4,727,960 has disclosccl another clutch of'this kind in a sonlewhat different arrangcnlcnt. Here, outilow opcnin~s with restrictions ai-c p--ovided between the thirci and lourtll Opening and the pressLIre space, allowing clifferent response pressures for the two possible directions ol'thc speed diffe--ence, i.e. a distinction between driving and overrun nlode anci forward and reverse travel.
In one enlbodinlent (fig. 7), cont--ol nlenlbe--s have furthel-more already been provided, nanlely ftu-ther outflow valves, the response pressure of wllich can be controlled.
The actuating signal for these valves is deternlined by a conti-oller from a variety of ope--ating va--iables. The control nlenlbers are accommodated in the rotating part and the actl-atino signals, which are hydraulic in this case, must therefore be supplied to them via a 1-otary input. No means of influencin" tlle pressure on the intake side of the displacement nlachine is provided. All tllis and, in addition, the action of the centriftigal force on the control members renders sensitive, accurate and rapid control inlpossible.
DE 198 54 867 A llas disclosed another clutch of tllis kind in yet another arrangement, In whlcll it ls not the dlsplacenient machine but the pressure chamber itself that is connected by a rotary input to a control valve, the latter being fixed to the housing, for pressure nlodulation on the delive--y side. This allows only inlperfect control. To tow the vellicle away, fo-- instance, the displacement maclline must be completely depressurized, and this requires a valve on the intake side as well. Moreover, the valve arrangement requires the entire clutch unit to be constrtlcted in a way that has many other disadvantages.
It is therefore the ohject of'the invention to develop a clutch of the generic type in such a way that sensitive, accurate and rapid cont--ol and aclaptation of the characteristic iS aSSLlred wlth tlle nllnlnlunl oUtllty. ACCordlilg to tlle lllvelltlOn, this is achieved by virtue of the fact that the first and the seconcl opening al-e eacil connected in ternls of flow to the rese--voi--, via a tirst anci scco-ut rotarV Illpllt and a li--st and sccond valve respectively, said valves heinI.; fixccl to the Ilousin", and that the first and second valve are designed as - ~ -controllable ttlr-ottle \,alvcs, witli tlic r-csult that a control action takes place botll at the supply side and at the dischargc side of the displacement nlachine, irrespective of the (lirection of tlle differcnlial sheccl.
Conh-ol valves are tllus Ilrovidcd on the deliver-y and on the intake side on the sllortest path to anci fr-onl the displacement machine, allowing the clutch to be acted upon directly witll ver-y little dclay in all conceivable di-iving states. Since these are contr-ollable tlu-ottle valves, wllich are therefor-e arranged in the nlain flow, control can be exercised sensitively and accurately over the entire actuating range.
In addition, there arc all the advantages of control valves that are arranged fixed to a liousing: sinlplicity of connection to tlle control unit, no 3d verse e f f. ec t s due ta centrifugal force, no linlitation in over-all size and ease of access. It also allows the working mediunl to be supplied and discharged on one side of the displacenlent nlachine, allowin(I
small-diaineter i-otary ioints to he provided in a relatively simple manner.
The additional outlay for the rotar-y leadthrough is balanced by the elimination of the nonreturn valves tliat Would be r-equired in the sanle Iine \\ ithout the two contr-ol valves.
In a preferred embodinlent, the first and the second valve form a conimon control valve (claim 2). Apart fi-om the consequent reduction in cost, tllis also ensures enllanced reliability without any loss of functionality in dr-iving operation.
Here, the first and second valve can be proportional valves (clainl 3) or be activated by a stepping moto--(clainl 4).
As a development o1'the iilvention, a double-acting nonreturn valve is provided between the third and fourth openin`, and the pr-essw-e chanlber- (claim 5).
Since with tllis valve onc side is always ollen, the llressure space can be depressurized very rapidly via this valve and the control valve, tllis bein, advantageous pa--ticularly in the case of brakin(I
(ABS, ESP). Moreover, the val\ c can be aCConllllodated in a particularly space-savlng nlanner in the wall bctwecn tli< displacement nlaclllrle and the pressure space. Owin~ to thc fact that it is onlv a sin,lc valve \\.ith a switching clcnlcnt (icleally witll a ball), a satis(actory transition I'roni one niodc of operation to the otllel- is assured.
If a coolint, passagc Ieads into the clutch space (i-onl the displacenlcnt nlachine via a throttle valve (claim b), this cnsures adequate Iubrication anci cooling of the clutch, promoting a rapid and crisp response fi-onl the latter.
An advantal"eous detail of'the invention comprises the common control valve being fonnecl by an actuating piston that can be displaceci in a bushing, the bushing being connected in tenns of flow to the 1-ese--voil- at both ends and having a first and a second latel-al control opening, one of which is connected to the displacenlent nlachine by the first opening and the otller is connecteci to the displacement machine by the second opening (delivery side and intake side respectively), and the actuating piston closing the first and tlle second control opening, respectively, in its two end positions and ctosing the two contl-ol openings reciprocally to ag1-eater ol- lesser extent in the intennediate positions.
(claim 7). As a result, the degrec to which the two valves open and close is interdependent, this being achieved with the minimum outlay in tenls of construction. Economy of space and accessibility are ful-ther inlproved if the bushing of the control valve is arranged in a plane transverse to the axis of rotation of the clutch, in the re,"ion of the rotary inputs.
(clainl 8).
Another advantageous detail of the invention compt-ises the double-acting nonreturn valve between the displacement machine and the pressure cllamber comprising a tangential hole in a plane tl-ansverse to the axis of 1-otation of the clutch and a closing body guided in said llole, the two ends of the tangential hole being connected to the tllird and iourth opening of the displacement 111aclline alld tllelr center belllg collnected to the pressure space. (claini 9). 'flle valve is thus unimpaired by centrifugal force, while taking uh thc minimum of spMcc.
l-he invention is described and explained below \vith 1-elerence to figures, of ~~ liicli:
Fig. I sllcl\\ s a first scllenlatic d4ai;ralll Of a ClltlCll ilccorcfing to the invention, FiIt'. 2 shows a seconcl scllenlatic dia~l-am ofa variant cnibodinlent of the clutch acco--ding to thc invcntion, Fig. 3 shows a l(lll!!Illldlllal sectl011 through a preferred embodinlent of the Illvelltloll, Fig. 4 sllows a vie\v from the front, partially b--oken away, and Fig. 5 shows a fi-ont vicw of'tlle intel-mediate plate 45 (fig. 3), partially broken away.
Fig. I is only a scllematic diagranl, in wllich the ]lydrostatic displacenlent machine is denoted by 1 and its totu- openings are denoted by 9, 10, 11 and 12, being combined to some extent for the sake of simplicity. From these there is a connection via the obligatory nonl-etunl valves 2, 3 to a pressw-e cllamber 4, which compresses a multi-plate clutch (not illustrated at this stage) by nleans of a piston 5. The connection to a I-eservoil- 8 is establisllecl N ia a tllrottle valve 7 and, if appl-opriate, via a filter 6. The openings 9, 10 are connected by a fil-st and seconci rotary input 13, 14 to a first and second control valve 15, 16.
The variant in fio. 2 cliffel-s fi-onl the above only in that a conlmon control valve 20 is pl-ovided instead of the two control valves and a conlnlon double nonreturn valve 22 is provided insteacl of the two nonreturn valves. The comnlon control valve 20 is controlled by a stepping nlotor 21.
In fig. 3, the housin", whicll sinlultaneously fornls the reservoir 8 for the wol-king fluid, is denoted by 25 and a connecting flange by 26. Within this, there is a drive housing 27, wlllch cllds 111 it drivc shaft 29 that is guided rotatably in the housing 25 by nleans of a bearin- 28. On tlle siclc renlote fronl the drive shaft 29, an output shaft 30 flro jects into the dl-ivc llousing, 27. It is supported in the housing 25 by nleans of a hcaring 31 . There are furthcrnlclre m o nccdle hcarings 32, 11 tilr nlutual support between the clrivc IlOusing 27 and the output sllalt M.
- (1 -Wltllln thc drive h(1Uslng 27 therc is a Iiydi-ostatic displacement machine, dcnotcd in general tei-ms by 35, ,ind a friction clutcl> ;6, wliich is a multi-plate clutch of a type known per se. Hcrc, thc hydrostatic displacement macliine 35 compi-ises an innei- rotor 17, which is connected rotationaily to the output shaft 30, and an outer rotor 38, which is fi-cely rotatable in an eccenti-ic manner in the di-ive housing. The two rotors 37, 38 have Cllf ferent nWllbers of -nternleshing tooth-like sti-uctures.
On the side i-emote from the fi-iction clutch 36, tlic clrive housing 27 contains a Ftrst and a second opening 9, 10 and, on the side adjacent to the fi-iction clutch 36, contains thii-d and foLu-th openings 11, 12. A first connecting (iole (or a plurality of successive holes) 39 leads from the first opening 9 to a fii-st i-otary input 13 between the drive housing 27 and housing 25. A second connecting hole 41 leads fi'om the second opening 10 to a second i-otary input 14, whicli is arranged axially offset relative to the first rotary input.
A first branch passage 43 and a secon(i brancli passage 44 lead from the two rotary inputs 13, 14 to the comnion control valve 20 (not shown), which is arranged in the connecting tlange 26 of the housing 25, i.e. In the Ilonrolating part. The tllird and fourth openings 11, 12 are in an intei-mediate plate 45, which is part of the drive housing 27 and which is adjoined directly by the hydi-ostatic displacement machine 35. Also located in the intei-mediate plate 45 is the common nonreturn valve 22 and the throttle valve 7.
On the opposite side of the intei-mediate plate 45 from the liydrostatic displacement machine tliere is first of all the pressin-e chamber 4 and then the piston 5, which presses the clutch plates 46, 47 together when the pressure chamber 4 is subjected to hressure. "i'he clutch plates 46 are connected in a rotationally fixed but axially displaceable niannei- to the di-ive housing 27, and the clutcli plates 47 ai-e connected in a rotationally fized but axially displaccable mauiner to the output shafi 30.
Fig. 4 shows, in pNIrticular, the contmon control valve 20, which is accommodated in a valve liore 50 in the connecting Ilan-c 20. It comprises a bushing 51, Ilich is inscrted and screwcd ii7to Ihr valve bore 50 and has a cylindi-ical bore 52 in which an actuatin~; piston 53 can be ~icljustcd by nlcans ol'thc sleppin~ motor 21.
The connectin~.
Ilange 26 llas a depression 54, by nicans ol'which the contlection to the working fluid in the t-cservoir is establishcd on onc side via a lirst inlet opening 56, possibly via a filter. At the othcr end OI tllt', bUSlllng 51, the workin- flnid Iias li-ce access to the cylindei- bore 52 via a second inlet openin, 57. The approximate oil level is indicated and denoted by 55.
Between the two inlct openings 56, 57, the bushing 51 llas two lateral conti-ol openings. The fii-st controi opening 58 is connected to the first branch passage 43, wllile the second conti-ol opening 59 is connected to the second branch passage 44 (see fig. 3).
Tlle conti-ol openings 5b, 59 do not necessai-ily have to be cylindrical; they can be adapted to nloi-e refined control rcduirenlcnts by nlo(tifyint., their shape. Also provided is a spring 70, wliich nioves the piston 53) autonlMically into the position shown on the extrenle left in special situations.
The operation of thc valve 22 will now be explained with reference to the tllree indicated positions of the actuatin~~ piston 53. In position 53 (solid ]ine), the first control opening 58 is conlpletelv closed and the second control opening 59 is conlpletely open. In position 53' (broken Iines), the fii-st conti-ol opening 58 is conlpletely open and the second contt-ol opening 59 is completely closed. In position 53" (broken lines), both control openings 58, 59 ai-e partially open. The effect of these valve positions depends on the direction of the speed (iifference in the hydrostatic displacement machine and thus on the driving state:
A) Forward drivin- nlodc: tllc adjusting piston is in the center position 53".
The second control opening 59 is opcn (to a greater or Iessei- extent) and acts as an intake opening, anci the tirst control opening 58 is likewise partially open, acting as a delivery ollening, and the actuating {liston is in position 53". In this position, the characteristic of tilc clutch is "entle, c.". lur n1ancuvrrin11 zllld corllerlnty on the i-oad.
If the clutch is supposed to be stiff for lli"her traction, i.e. to tr,lnsnllt a high torqtie, e.g. when off=road oi-when the wheels are spinning, the actuating piston is moved into position 53, in which the first control opening 58 is closed.
B) Forward overrun mode: during overrun braking, the first control opening 58 is open (this being now delivery side) and the second control opening 59 is largely closed, while the actuating piston is in position 53'. If anti-lock braking occurs, the second control opening 59 is opened quickly, this being assisted by the spring, and the actuating piston is then in position 53.
C) Reverse driving mode: the second control opening 59 is closed, the first control opening 58 is open and the actuating piston is between positions 53' and 53" in the control mode.
D) Reverse overrun mode: both openings 58, 59 are partially open, corresponding to position 53" of the actuating piston.
E) Forward tow-away: the first control opening must be open and the second control opening 59 (corresponding to the intake side) must be largely closed to avoid the occurrence of drag resistance when being towed away.
Fig. 5 shows two further valves, the throttle valve 7 and the common double-acting nonreturn valve 22. Both are accommodated in the intermediate plate 45 (see also Fig. 3). From the pressure space 4, pressure medium passes through the connecting hole 60 into the throttle-valve bore 64, into which a throttling pin 62 is screwed in an adjustable manner. Together with the throttle-valve bore 64, this pin forms a restriction 63, adjoining which on the inside is a cooling passage 48 that leads into the clutch space 61 (Fig. 3).
The common nonretum valve comprises a tangential hole 65, which is closed pressure-tightly at one end by a plug 69, and a closing body 71, which can move therein. The third and fourth openings 11, 12 of the hydrostatic displacement machine 35 open into the tangential hole 65. On one side, between these openings 11, 12, there is a stop shoulder 67 and, on the other side, there is a screwed-on stop ring 68. The closing body 71, in this case a ball, can move backward and forward between these two stops 67, 68.
Approximately in the ccntci- between thc two eixl positions of thc closing bocly 7 1 tllere is a through-opcning 00, which establishes the connection witli the pressure chanlher 4. Dependin, in which ol tllc tw0 openings I l, 12 the preSSUre lS
I11fJllct", thc ball 7 1 assumes a positioil in which one ol_thc two opcnings 11, 12 is connected to the inlet opening 66. This provides tlle cloublc-actin0 nonreturn valve 22.
VALVES
The invention relates to a speed-difference-dependent hydraulic clutch, comprising a drive housing, which rotates in a housing that is fixed in space and fon-ns a i-eservoir for a working fluid, a hydrostatic displacement machine, wliich is accommodated in said drive housing, a drive shaft, a friction clt-tch for connecting the drive shaft to the drive housing and a piston for actin- on the friction clutch, a pt-essure being produced in a pressui-e space when a difference occurs between the speed of the drive housing and that of the drive shaft, this pressure giving rise to action upon the fi-iction clutch, and the hydt-ostatic displacement machine havin~.; a first and a second opening for the supply and discharge of working medium and a third and fourtlz opening for connection to the pressure chamber.
Clutches of tliis kinci are uscd in various configLn-ations in the drive train of motor vehicles foi- direct transmission of a torque or locking a linked differential for the puIpose of driving the wheels on one axle ot- distributing the drive torque between two axles. The hydrostatic displacement machine comprises an inner rotor and an outer rotor, foi- example, but it is equally possible 10 use liydi-ostatic displacement machines of some othet- kind. In eitller case, two parts (c.t;. the drive housing and the otitput shaft) perform a i-clative motion when there is a speed diffei-ence and thus produce a pressure that acts on thc piston of the li-iction clutch.
A clutcll ot thls klnd is ktlown, for exatnple, fi-oni US-A 5,536,215. ]n this, a valve formed by a bII1lCtallic Iral'is provided between the pt-essure space and a space at low pressure, tlie clutch space, tllis v~ilvc hcin,~:,N intended to compensate for temperature-deheildcnt changes in tlle viscositv of tllc working fluid. Therc are no tiirther control 111cn1I)Crs.
- ~ -US 4,727,960 has disclosccl another clutch of'this kind in a sonlewhat different arrangcnlcnt. Here, outilow opcnin~s with restrictions ai-c p--ovided between the thirci and lourtll Opening and the pressLIre space, allowing clifferent response pressures for the two possible directions ol'thc speed diffe--ence, i.e. a distinction between driving and overrun nlode anci forward and reverse travel.
In one enlbodinlent (fig. 7), cont--ol nlenlbe--s have furthel-more already been provided, nanlely ftu-ther outflow valves, the response pressure of wllich can be controlled.
The actuating signal for these valves is deternlined by a conti-oller from a variety of ope--ating va--iables. The control nlenlbers are accommodated in the rotating part and the actl-atino signals, which are hydraulic in this case, must therefore be supplied to them via a 1-otary input. No means of influencin" tlle pressure on the intake side of the displacement nlachine is provided. All tllis and, in addition, the action of the centriftigal force on the control members renders sensitive, accurate and rapid control inlpossible.
DE 198 54 867 A llas disclosed another clutch of tllis kind in yet another arrangement, In whlcll it ls not the dlsplacenient machine but the pressure chamber itself that is connected by a rotary input to a control valve, the latter being fixed to the housing, for pressure nlodulation on the delive--y side. This allows only inlperfect control. To tow the vellicle away, fo-- instance, the displacement maclline must be completely depressurized, and this requires a valve on the intake side as well. Moreover, the valve arrangement requires the entire clutch unit to be constrtlcted in a way that has many other disadvantages.
It is therefore the ohject of'the invention to develop a clutch of the generic type in such a way that sensitive, accurate and rapid cont--ol and aclaptation of the characteristic iS aSSLlred wlth tlle nllnlnlunl oUtllty. ACCordlilg to tlle lllvelltlOn, this is achieved by virtue of the fact that the first and the seconcl opening al-e eacil connected in ternls of flow to the rese--voi--, via a tirst anci scco-ut rotarV Illpllt and a li--st and sccond valve respectively, said valves heinI.; fixccl to the Ilousin", and that the first and second valve are designed as - ~ -controllable ttlr-ottle \,alvcs, witli tlic r-csult that a control action takes place botll at the supply side and at the dischargc side of the displacement nlachine, irrespective of the (lirection of tlle differcnlial sheccl.
Conh-ol valves are tllus Ilrovidcd on the deliver-y and on the intake side on the sllortest path to anci fr-onl the displacement machine, allowing the clutch to be acted upon directly witll ver-y little dclay in all conceivable di-iving states. Since these are contr-ollable tlu-ottle valves, wllich are therefor-e arranged in the nlain flow, control can be exercised sensitively and accurately over the entire actuating range.
In addition, there arc all the advantages of control valves that are arranged fixed to a liousing: sinlplicity of connection to tlle control unit, no 3d verse e f f. ec t s due ta centrifugal force, no linlitation in over-all size and ease of access. It also allows the working mediunl to be supplied and discharged on one side of the displacenlent nlachine, allowin(I
small-diaineter i-otary ioints to he provided in a relatively simple manner.
The additional outlay for the rotar-y leadthrough is balanced by the elimination of the nonreturn valves tliat Would be r-equired in the sanle Iine \\ ithout the two contr-ol valves.
In a preferred embodinlent, the first and the second valve form a conimon control valve (claim 2). Apart fi-om the consequent reduction in cost, tllis also ensures enllanced reliability without any loss of functionality in dr-iving operation.
Here, the first and second valve can be proportional valves (clainl 3) or be activated by a stepping moto--(clainl 4).
As a development o1'the iilvention, a double-acting nonreturn valve is provided between the third and fourth openin`, and the pr-essw-e chanlber- (claim 5).
Since with tllis valve onc side is always ollen, the llressure space can be depressurized very rapidly via this valve and the control valve, tllis bein, advantageous pa--ticularly in the case of brakin(I
(ABS, ESP). Moreover, the val\ c can be aCConllllodated in a particularly space-savlng nlanner in the wall bctwecn tli< displacement nlaclllrle and the pressure space. Owin~ to thc fact that it is onlv a sin,lc valve \\.ith a switching clcnlcnt (icleally witll a ball), a satis(actory transition I'roni one niodc of operation to the otllel- is assured.
If a coolint, passagc Ieads into the clutch space (i-onl the displacenlcnt nlachine via a throttle valve (claim b), this cnsures adequate Iubrication anci cooling of the clutch, promoting a rapid and crisp response fi-onl the latter.
An advantal"eous detail of'the invention comprises the common control valve being fonnecl by an actuating piston that can be displaceci in a bushing, the bushing being connected in tenns of flow to the 1-ese--voil- at both ends and having a first and a second latel-al control opening, one of which is connected to the displacenlent nlachine by the first opening and the otller is connecteci to the displacement machine by the second opening (delivery side and intake side respectively), and the actuating piston closing the first and tlle second control opening, respectively, in its two end positions and ctosing the two contl-ol openings reciprocally to ag1-eater ol- lesser extent in the intennediate positions.
(claim 7). As a result, the degrec to which the two valves open and close is interdependent, this being achieved with the minimum outlay in tenls of construction. Economy of space and accessibility are ful-ther inlproved if the bushing of the control valve is arranged in a plane transverse to the axis of rotation of the clutch, in the re,"ion of the rotary inputs.
(clainl 8).
Another advantageous detail of the invention compt-ises the double-acting nonreturn valve between the displacement machine and the pressure cllamber comprising a tangential hole in a plane tl-ansverse to the axis of 1-otation of the clutch and a closing body guided in said llole, the two ends of the tangential hole being connected to the tllird and iourth opening of the displacement 111aclline alld tllelr center belllg collnected to the pressure space. (claini 9). 'flle valve is thus unimpaired by centrifugal force, while taking uh thc minimum of spMcc.
l-he invention is described and explained below \vith 1-elerence to figures, of ~~ liicli:
Fig. I sllcl\\ s a first scllenlatic d4ai;ralll Of a ClltlCll ilccorcfing to the invention, FiIt'. 2 shows a seconcl scllenlatic dia~l-am ofa variant cnibodinlent of the clutch acco--ding to thc invcntion, Fig. 3 shows a l(lll!!Illldlllal sectl011 through a preferred embodinlent of the Illvelltloll, Fig. 4 sllows a vie\v from the front, partially b--oken away, and Fig. 5 shows a fi-ont vicw of'tlle intel-mediate plate 45 (fig. 3), partially broken away.
Fig. I is only a scllematic diagranl, in wllich the ]lydrostatic displacenlent machine is denoted by 1 and its totu- openings are denoted by 9, 10, 11 and 12, being combined to some extent for the sake of simplicity. From these there is a connection via the obligatory nonl-etunl valves 2, 3 to a pressw-e cllamber 4, which compresses a multi-plate clutch (not illustrated at this stage) by nleans of a piston 5. The connection to a I-eservoil- 8 is establisllecl N ia a tllrottle valve 7 and, if appl-opriate, via a filter 6. The openings 9, 10 are connected by a fil-st and seconci rotary input 13, 14 to a first and second control valve 15, 16.
The variant in fio. 2 cliffel-s fi-onl the above only in that a conlmon control valve 20 is pl-ovided instead of the two control valves and a conlnlon double nonreturn valve 22 is provided insteacl of the two nonreturn valves. The comnlon control valve 20 is controlled by a stepping nlotor 21.
In fig. 3, the housin", whicll sinlultaneously fornls the reservoir 8 for the wol-king fluid, is denoted by 25 and a connecting flange by 26. Within this, there is a drive housing 27, wlllch cllds 111 it drivc shaft 29 that is guided rotatably in the housing 25 by nleans of a bearin- 28. On tlle siclc renlote fronl the drive shaft 29, an output shaft 30 flro jects into the dl-ivc llousing, 27. It is supported in the housing 25 by nleans of a hcaring 31 . There are furthcrnlclre m o nccdle hcarings 32, 11 tilr nlutual support between the clrivc IlOusing 27 and the output sllalt M.
- (1 -Wltllln thc drive h(1Uslng 27 therc is a Iiydi-ostatic displacement machine, dcnotcd in general tei-ms by 35, ,ind a friction clutcl> ;6, wliich is a multi-plate clutch of a type known per se. Hcrc, thc hydrostatic displacement macliine 35 compi-ises an innei- rotor 17, which is connected rotationaily to the output shaft 30, and an outer rotor 38, which is fi-cely rotatable in an eccenti-ic manner in the di-ive housing. The two rotors 37, 38 have Cllf ferent nWllbers of -nternleshing tooth-like sti-uctures.
On the side i-emote from the fi-iction clutch 36, tlic clrive housing 27 contains a Ftrst and a second opening 9, 10 and, on the side adjacent to the fi-iction clutch 36, contains thii-d and foLu-th openings 11, 12. A first connecting (iole (or a plurality of successive holes) 39 leads from the first opening 9 to a fii-st i-otary input 13 between the drive housing 27 and housing 25. A second connecting hole 41 leads fi'om the second opening 10 to a second i-otary input 14, whicli is arranged axially offset relative to the first rotary input.
A first branch passage 43 and a secon(i brancli passage 44 lead from the two rotary inputs 13, 14 to the comnion control valve 20 (not shown), which is arranged in the connecting tlange 26 of the housing 25, i.e. In the Ilonrolating part. The tllird and fourth openings 11, 12 are in an intei-mediate plate 45, which is part of the drive housing 27 and which is adjoined directly by the hydi-ostatic displacement machine 35. Also located in the intei-mediate plate 45 is the common nonreturn valve 22 and the throttle valve 7.
On the opposite side of the intei-mediate plate 45 from the liydrostatic displacement machine tliere is first of all the pressin-e chamber 4 and then the piston 5, which presses the clutch plates 46, 47 together when the pressure chamber 4 is subjected to hressure. "i'he clutch plates 46 are connected in a rotationally fixed but axially displaceable niannei- to the di-ive housing 27, and the clutcli plates 47 ai-e connected in a rotationally fized but axially displaccable mauiner to the output shafi 30.
Fig. 4 shows, in pNIrticular, the contmon control valve 20, which is accommodated in a valve liore 50 in the connecting Ilan-c 20. It comprises a bushing 51, Ilich is inscrted and screwcd ii7to Ihr valve bore 50 and has a cylindi-ical bore 52 in which an actuatin~; piston 53 can be ~icljustcd by nlcans ol'thc sleppin~ motor 21.
The connectin~.
Ilange 26 llas a depression 54, by nicans ol'which the contlection to the working fluid in the t-cservoir is establishcd on onc side via a lirst inlet opening 56, possibly via a filter. At the othcr end OI tllt', bUSlllng 51, the workin- flnid Iias li-ce access to the cylindei- bore 52 via a second inlet openin, 57. The approximate oil level is indicated and denoted by 55.
Between the two inlct openings 56, 57, the bushing 51 llas two lateral conti-ol openings. The fii-st controi opening 58 is connected to the first branch passage 43, wllile the second conti-ol opening 59 is connected to the second branch passage 44 (see fig. 3).
Tlle conti-ol openings 5b, 59 do not necessai-ily have to be cylindrical; they can be adapted to nloi-e refined control rcduirenlcnts by nlo(tifyint., their shape. Also provided is a spring 70, wliich nioves the piston 53) autonlMically into the position shown on the extrenle left in special situations.
The operation of thc valve 22 will now be explained with reference to the tllree indicated positions of the actuatin~~ piston 53. In position 53 (solid ]ine), the first control opening 58 is conlpletelv closed and the second control opening 59 is conlpletely open. In position 53' (broken Iines), the fii-st conti-ol opening 58 is conlpletely open and the second contt-ol opening 59 is completely closed. In position 53" (broken lines), both control openings 58, 59 ai-e partially open. The effect of these valve positions depends on the direction of the speed (iifference in the hydrostatic displacement machine and thus on the driving state:
A) Forward drivin- nlodc: tllc adjusting piston is in the center position 53".
The second control opening 59 is opcn (to a greater or Iessei- extent) and acts as an intake opening, anci the tirst control opening 58 is likewise partially open, acting as a delivery ollening, and the actuating {liston is in position 53". In this position, the characteristic of tilc clutch is "entle, c.". lur n1ancuvrrin11 zllld corllerlnty on the i-oad.
If the clutch is supposed to be stiff for lli"her traction, i.e. to tr,lnsnllt a high torqtie, e.g. when off=road oi-when the wheels are spinning, the actuating piston is moved into position 53, in which the first control opening 58 is closed.
B) Forward overrun mode: during overrun braking, the first control opening 58 is open (this being now delivery side) and the second control opening 59 is largely closed, while the actuating piston is in position 53'. If anti-lock braking occurs, the second control opening 59 is opened quickly, this being assisted by the spring, and the actuating piston is then in position 53.
C) Reverse driving mode: the second control opening 59 is closed, the first control opening 58 is open and the actuating piston is between positions 53' and 53" in the control mode.
D) Reverse overrun mode: both openings 58, 59 are partially open, corresponding to position 53" of the actuating piston.
E) Forward tow-away: the first control opening must be open and the second control opening 59 (corresponding to the intake side) must be largely closed to avoid the occurrence of drag resistance when being towed away.
Fig. 5 shows two further valves, the throttle valve 7 and the common double-acting nonreturn valve 22. Both are accommodated in the intermediate plate 45 (see also Fig. 3). From the pressure space 4, pressure medium passes through the connecting hole 60 into the throttle-valve bore 64, into which a throttling pin 62 is screwed in an adjustable manner. Together with the throttle-valve bore 64, this pin forms a restriction 63, adjoining which on the inside is a cooling passage 48 that leads into the clutch space 61 (Fig. 3).
The common nonretum valve comprises a tangential hole 65, which is closed pressure-tightly at one end by a plug 69, and a closing body 71, which can move therein. The third and fourth openings 11, 12 of the hydrostatic displacement machine 35 open into the tangential hole 65. On one side, between these openings 11, 12, there is a stop shoulder 67 and, on the other side, there is a screwed-on stop ring 68. The closing body 71, in this case a ball, can move backward and forward between these two stops 67, 68.
Approximately in the ccntci- between thc two eixl positions of thc closing bocly 7 1 tllere is a through-opcning 00, which establishes the connection witli the pressure chanlher 4. Dependin, in which ol tllc tw0 openings I l, 12 the preSSUre lS
I11fJllct", thc ball 7 1 assumes a positioil in which one ol_thc two opcnings 11, 12 is connected to the inlet opening 66. This provides tlle cloublc-actin0 nonreturn valve 22.
Claims (9)
1. A speed-difference-dependent hydraulic clutch, comprising a drive housing (27), which rotates in a housing (25) that is fixed in space and forms a reservoir for a working fluid, a hydrostatic displacement machine (35), which is accommodated in said drive housing, an output shaft (30), a friction clutch (36) for connecting the output shaft (30) to the drive housing (27) and a piston (5) for acting on the friction clutch (36), a pressure being produced in a pressure chamber (4) when a difference occurs between the speed of the drive housing (27) and that of the output shaft (30), this pressure giving rise to action upon the friction clutch (36), and the hydrostatic displacement machine (35) having a first (9) and a second (10) opening (9, 10) for the supply and discharge of working medium and a third (11) and forth (12) opening (11, 12) for connection to the pressure chamber (4), wherein the first and the second opening (9, 10) are each connected in terms of flow to the reservoir (8), via a first and second rotary input (13, 14) and a first and second control valve (15, 16) respectively, said valves being fixed to the housing, the first and second control valve (15, 16) being designed as controllable throttle valves, with the result that a control action takes place both at the respective supply side and at the discharge side of the displacement machine, irrespective of the direction of the differential speed.
2. The speed-difference-dependent hydraulic clutch as claimed in claim 1, wherein the first and the second control valve (15, 16) form a common control valve (20).
3. The speed difference-dependent hydraulic clutch as claimed in claim 1, wherein the first and the second control valve (15, 16) are proportional valves.
4. The speed-difference-dependent hydraulic clutch as claimed in claim 1, wherein the first and the second control valve (15, 16; 20) are activated by a stepping motor (21).
5. The speed-difference-dependent hydraulic clutch as claimed in claim 1, wherein a double-acting nonreturn valve (22) is provided between the third and fourth opening (11, 12) and the pressure chamber (4).
6. The speed-difference-dependent hydraulic clutch as claimed in claim 5, wherein a cooling passage (48) leads into the clutch space (61) from the displacement machine (35) via a throttle valve (7).
7. The speed-difference-dependent hydraulic clutch as claimed in claim 2, wherein the common control valve (20) is formed by an actuating piston (53) that can be displaced in a bushing (51), the bushing having inlet openings (56, 57) to the reservoir (8) at both ends and having a first (59) and a second (58) lateral control opening (58, 59), one (59) of which is connected to the displacement machine (35) by the second inlet opening (57) and the other (58) is connected to the displacement machine (35) by the first inlet opening (56) (delivery side and intake side respectively), and the actuating piston (53) closing the first (58) and the second (59) control opening, respectively, in its two end positions (53, 5 3") and closing the two control openings (58, 59) reciprocally to a greater or lesser extent in the intermediate positions (53').
8. The speed-difference-dependent hydraulic clutch as claimed in claim 7, wherein the bushing (51) of the control valve (20) is arranged in a plane transverse to the axis of rotation Of the clutch, in the region of the rotary inputs (13, 14).
9. The speed-difference-dependent hydraulic clutch as claimed in claim 5, wherein the double-acting nonreturn valve (22) between the displacement machine (35) and the pressure chamber (4) comprises a tangential hole (65) in a plane transverse to the axis of rotation of the clutch and a closing body (71) guided in said hole, the two ends of the tangential hole (65) being connected to the third and fourth opening (11, 12) of the displacement machine (35) and their center being connected to the pressure chamber (4).
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT0070399U AT3832U1 (en) | 1999-10-12 | 1999-10-12 | SPEED DIFFERENTIAL-RELATED HYDRAULIC CLUTCH WITH CONTROL VALVES |
| ATGM703/99 | 1999-10-12 | ||
| PCT/AT2000/000264 WO2001027487A1 (en) | 1999-10-12 | 2000-10-12 | Rotational speed differential hydraulic clutch having control valves |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2385717A1 CA2385717A1 (en) | 2001-04-19 |
| CA2385717C true CA2385717C (en) | 2009-11-24 |
Family
ID=3497594
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002385717A Expired - Fee Related CA2385717C (en) | 1999-10-12 | 2000-10-12 | Speed-difference-dependent hydraulic clutch with control valves |
Country Status (6)
| Country | Link |
|---|---|
| US (2) | US6484856B1 (en) |
| EP (1) | EP1224405B1 (en) |
| AT (2) | AT3832U1 (en) |
| CA (1) | CA2385717C (en) |
| DE (1) | DE50009376D1 (en) |
| WO (1) | WO2001027487A1 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT3832U1 (en) * | 1999-10-12 | 2000-08-25 | Steyr Daimler Puch Ag | SPEED DIFFERENTIAL-RELATED HYDRAULIC CLUTCH WITH CONTROL VALVES |
| AT4837U1 (en) | 2000-09-27 | 2001-12-27 | Steyr Powertrain Ag & Co Kg | DRIVE SYSTEM FOR AN ALL-WHEEL DRIVE MOTOR VEHICLE |
| US6938221B2 (en) * | 2001-11-30 | 2005-08-30 | Microsoft Corporation | User interface for stylus-based user input |
| US20040097323A1 (en) * | 2002-11-15 | 2004-05-20 | Duan Xiaohong N. | Torque biasing assembly and method |
| AT6574U1 (en) | 2002-11-29 | 2003-12-29 | Magna Steyr Powertrain Ag & Co | SPEED DIFFERENTIAL COUPLING WITH MAGNETORHEOLOGICAL WORKING FLUID |
| WO2004097241A2 (en) | 2003-04-28 | 2004-11-11 | Magna Steyr Powertrain Ag & Co Kg | Rotation speed dependent hydraulic clutch provided with a control valve |
| DE102004048085A1 (en) * | 2004-09-30 | 2006-04-06 | Zf Friedrichshafen Ag | Switchable stabilizer for a motor vehicle |
| DE102006037991A1 (en) * | 2006-08-14 | 2008-02-21 | Magna Powertrain Ag & Co Kg | Clutch unit for drive train of motor vehicle, has outlet channel and drainage borehole with progression aligned radially outwards or parallel to rotational axis in central area with respect to flow direction of fluid |
| JP6410854B2 (en) | 2017-01-24 | 2018-10-24 | 本田技研工業株式会社 | Hydraulic clutch device |
| WO2018145690A1 (en) * | 2017-02-10 | 2018-08-16 | Schaeffler Technologies AG & Co. KG | Actuation device for a clutch, and production method |
Family Cites Families (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3800930A (en) * | 1972-09-22 | 1974-04-02 | Sommer Co | Variable speed drive |
| US3894446A (en) * | 1974-06-03 | 1975-07-15 | Twin Disc Inc | Power transmission having friction clutch bias differential with automatic clutch release |
| US4719998A (en) * | 1984-05-29 | 1988-01-19 | Mitsubishi Jidosha Kogyo Kabushiki Kaisha | Power transmission system for vehicle |
| US4727966A (en) * | 1984-05-30 | 1988-03-01 | Mitsubishi Jidosha Kogyo Kabushiki Kaisha | Differential with differential motion limiting mechanism |
| US4581895A (en) * | 1984-06-18 | 1986-04-15 | Deere & Company | Hydrostatic transaxle assembly |
| FR2623581B1 (en) * | 1987-11-25 | 1991-09-27 | Valeo | SYSTEM FOR AUTOMATICALLY CONTROLLING A COUPLING CLUTCH OF TWO ROTATING SHAFTS |
| JPH04151029A (en) * | 1990-10-11 | 1992-05-25 | Toyoda Mach Works Ltd | Driving power transmission device |
| US5536215A (en) | 1993-02-10 | 1996-07-16 | Asha Corporation | Hydraulic coupling for vehicle drivetrain |
| US5611746A (en) * | 1995-06-28 | 1997-03-18 | Asha Corporation | Vehicle drivetrain coupling |
| US5827145A (en) * | 1997-03-17 | 1998-10-27 | Asha Corporation | Hydraulic coupling having supplemental actuation |
| US6041903A (en) * | 1997-12-17 | 2000-03-28 | New Venture Gear, Inc. | Hydraulic coupling for vehicular power transfer systems |
| AT405967B (en) * | 1997-12-23 | 2000-01-25 | Steyr Daimler Puch Ag | SPEED DIFFERENTIAL-RELATED HYDRAULIC CLUTCH |
| US5964126A (en) * | 1998-09-02 | 1999-10-12 | Mclaren Automotive Group, Inc. | Hydraulic coupling for auxiliary drive axle of a vehicle drivetrain |
| AT2964U1 (en) * | 1998-09-25 | 1999-07-26 | Steyr Daimler Puch Ag | POWER TRANSMISSION UNIT WITH SPEED-RELATED HYDRAULIC CLUTCH |
| AT3020U1 (en) * | 1998-10-29 | 1999-08-25 | Steyr Daimler Puch Ag | SPEED DIFFERENTIAL-RELATED HYDRAULIC CLUTCH WITH TORQUE LIMIT |
| US6120408A (en) * | 1999-03-08 | 2000-09-19 | Mclaren Automotive Group, Inc. | Limited slip differential with temperature compensating valve |
| AT3832U1 (en) * | 1999-10-12 | 2000-08-25 | Steyr Daimler Puch Ag | SPEED DIFFERENTIAL-RELATED HYDRAULIC CLUTCH WITH CONTROL VALVES |
-
1999
- 1999-10-12 AT AT0070399U patent/AT3832U1/en not_active IP Right Cessation
- 1999-10-12 AT AT00967416T patent/ATE288037T1/en not_active IP Right Cessation
-
2000
- 2000-10-12 WO PCT/AT2000/000264 patent/WO2001027487A1/en active IP Right Grant
- 2000-10-12 CA CA002385717A patent/CA2385717C/en not_active Expired - Fee Related
- 2000-10-12 US US09/689,198 patent/US6484856B1/en not_active Expired - Lifetime
- 2000-10-12 DE DE50009376T patent/DE50009376D1/en not_active Expired - Lifetime
- 2000-10-12 US US10/110,352 patent/US6684991B1/en not_active Expired - Fee Related
- 2000-10-12 EP EP00967416A patent/EP1224405B1/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| ATE288037T1 (en) | 2005-02-15 |
| EP1224405B1 (en) | 2005-01-26 |
| US6484856B1 (en) | 2002-11-26 |
| US6684991B1 (en) | 2004-02-03 |
| CA2385717A1 (en) | 2001-04-19 |
| DE50009376D1 (en) | 2005-03-03 |
| EP1224405A1 (en) | 2002-07-24 |
| WO2001027487A1 (en) | 2001-04-19 |
| AT3832U1 (en) | 2000-08-25 |
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