WO2020157255A1

WO2020157255A1 - Wet dual clutch and elastic return device for such a wet dual clutch

Info

Publication number: WO2020157255A1
Application number: PCT/EP2020/052389
Authority: WO
Inventors: Arnaud DOLE; Vincent CORNET
Original assignee: Valeo Embrayages
Priority date: 2019-01-31
Filing date: 2020-01-31
Publication date: 2020-08-06
Also published as: CN113366235A; FR3092373A1; CN113366235B; FR3092373B1

Abstract

Wet dual clutch (1) for a motor vehicle, comprising - a first (E1) and a second (E2) multi-disc clutch which rotate about an axis (X) and are controlled to selectively engage a drive shaft with a first output shaft (A1) and with a second output shaft (A2) by means of a shared torque input disc carrier (10), the first clutch (E1) being arranged radially beyond the second clutch (E2), - a first and a second force-transmission member (65, 75) which are designed to control the first and second clutches (E1, E2), and - an elastic return device (60) for the first and the second force-transmission member (65, 75), which elastic return device is supported on the input disc carrier (10), the elastic return device (60) being common to the first and the second force-transmission member (65, 75), the elastic return device (60) and the input disc carrier (10) being rotationally coupled by anti-rotation means (81, 82), the anti-rotation means (81, 82) forming an interlocking connection.

Description

Title of the invention: DOUBLE WET CLUTCH AND ELASTIC RETURN DEVICE FOR SUCH A DOUBLE WET CLUTCH

[1] [The present invention relates to a wet double clutch, as used in the automotive field. The invention also relates to an elastic return device for such a wet double clutch.

[2] Wet double clutches are known comprising a first and a second clutches as well as a first and a second actuator making it possible to generate a force to respectively configure the first and the second clutches in an engaged or disengaged configuration. The force generated at each actuator is transmitted to the clutch

corresponding through a force transmitting member of the form of revolution about an X axis of rotation of the wet double clutch. Thus, the movement of the actuator is transmitted to the corresponding force transmitting member which, in turn, moves first friction elements, for example friction discs, relative to second friction elements of the corresponding clutch, for example flanges, in order to configure it in one or other of the cited configurations.

[3] In a known manner, if the actuator is implemented in order to push the force transmission member, the retrograde movement of said actuator is generated by a resilient washer making it possible to generate a sufficient force to restore the actuator and the 'corresponding clutch in their initial configurations. This spring washer is generally made in the form of a Belleville washer, interposed between a clutch disc carrier and the force transmission member. This type of solution is axially bulky.

[4] It is possible to replace this elastic washer by elastic return means produced in the form of helical compression springs. This elastic return device is known from document US20050017422 A1 for application to a simple wet clutch. [5] This elastic return device comprises a first and second annular support plates as well as helical springs arranged

circumferentially and assembled between the first and second backing plates.

[6] In the context of a wet double clutch, it is known to have two separate elastic return devices of the aforementioned type between the disc carrier and the force transmission members of the first and second clutches. The two devices are assembled into each other in a concentric fashion.

[7] Due to geometric defects in alignment and centering of

components of the wet double clutch, the two devices can offset each other along the X axis of rotation, and interfere with each other.

[8] Elastic return devices can also be subjected to

Undesirable phenomena of rotation or sliding of the backing plates relative to the disc carrier, causing component wear.

[9] Document EP2913554 B1 discloses a solution for maintaining the elastic return device in position by means of a tight fitting of one of the annular support plates on an actuating piston.

[10] Deformable tabs formed on the periphery of the backing plate

allow a tight fitting of the elastic return device preventing its rotation. However, the assembly of such a device has drawbacks. When fitting the device into the piston

actuation, it is necessary to deform the tabs and press one of the annular backing plates against the bottom of the piston. However, the compression of the coil springs creates a rebound phenomenon preventing the backing plate from being correctly adjusted to the bottom of the piston. There is a risk of bad

positioning of the elastic return device. This solution entails a complex assembly operation and additional control. In addition, this solution is incompatible with elastic return devices assembled one inside the other in a concentric manner. [1 1] The object of the present invention is to respond at least to a large extent to the above problems and also to lead to other advantages.

[12] The aim of the invention is in particular to provide a simple, effective and economical solution to this problem.

[13] To this end, the invention provides, according to a first of its aspects, a wet double clutch for a motor vehicle, comprising:

a first clutch and a second clutch respectively of the multi-disc type rotating about an X axis, controlled to selectively couple a shaft leading to a first driven shaft and to a second driven shaft by means of a disc carrier d 'common torque input, the first clutch being disposed radially beyond the second clutch,

- A first member and a second force transmission member arranged to control the first and second clutches, and

- an elastic return device of the first member and of the second force transmission member resting on the input disc holder

characterized in that said elastic return device is common to the first member and to the second force transmission member,

said elastic return device and the input disc holder being rotatably coupled by anti-rotation means, said anti-rotation means forming an interlocking connection.

[14] This wet double clutch, according to the invention, has the advantage of

facilitate assembly and reduce the number of components, since the elastic return device is common to the first and second force transmission members. The assembly is facilitated by the interlocking of the anti-rotation means of the elastic return device and of the input disk holder without the need to deform them. The elastic return device can be mounted manually on the input disc holder without special tools. The interlocking connection ensures indexing and angular positioning of the elastic return device relative to the disc holder, which prevents any rotation of the device during its operation on the vehicle. Wear phenomena are thus avoided. [15] Preferably, the elastic return device can comprise:

- a first series and a second series of helical springs, each being angularly distributed around the X axis;

- a first support plate supporting the first series of coil springs and pressing on the first force transmission member;

- a second support plate supporting the second series of coil springs and pressing on the second force transmission member; and;

- a support plate common to the first and second series of springs, of annular shape, on which anti-rotation means of the elastic return device are formed on the outer periphery of the ring.

[16] This elastic return device, according to the invention, has the advantage of reducing the number of components and improving the centering accuracy of each set of coil springs. The use of a common backing plate eliminates the risk of interference of the first and second backing plates with each other.

[17] The positioning of the anti-rotation means on the outer periphery of the ring improves centering accuracy and limits the residual angular play between the device and the input disc holder.

[18] The outer periphery thus performs the functions of centering and anti

rotation of the device on an area of the input disc holder located radially under the multi-disc clutches. This area of the input disc holder is generally untapped.

[19] Preferably, the input disc holder (10) may include:

- an outer disc holder of the first clutch;

- an internal disc carrier of the second clutch;

- a plate made of sheet steel extending radially with respect to the X axis jointly supporting the outer and inner disc holder, on which anti-rotation means of the input disc holder are formed by stamping . a bearing plate common to the first and second series of springs, of annular shape, on which anti-rotation means of the elastic return device are formed on the outer periphery of the ring.

[20] The input disc carrier has the advantage of making anti-rotation means economically. From a stamped steel sheet, an input disc holder is formed and in particular a plate ensuring a large number of functions, such as: the transmission of the engine torque, the joint support of the outer and inner disc holders , the support of the forces within the first and second clutches E1, E2, as well as part of the anti-rotation means. In addition, the stamping of the sheet allows the realization of anti-rotation means having complex shapes, without machining.

[21] The shape of the anti-rotation means of the elastic return device and the shape of the anti-rotation means of the input disc holder are

complementary and realize a connection by interlocking. This cooperation of complementary shapes ensures the indexing and angular positioning of the elastic return device.

[22] The invention may exhibit one or the other of the characteristics described below combined with each other or taken independently of one another:

[23] - The second support plate may surround the first support plate;

[24] - The anti-rotation means of the input disc holder can be formed radially on the inside diameter of the plate of the input disc holder;

[25] - The anti-rotation means of the input disc holder can be formed radially below the inner disc holder;

[26] - The plate may include a shoulder on its internal periphery, said shoulder forming an internal volume suitable for receiving a guide bearing;

[27] - The anti-rotation means of the input disc carrier can be formed radially beyond the shoulder, without altering the axial size of the wet double clutch; [28] - The anti-rotation means of the common support plate can be stamped and arranged to adapt to the shape of the stampings of the input disc holder;

[29] - The common support plate of the elastic return device can rest on the plate of the input disc holder at an annular-shaped depression located radially below the inner disc holder. In this way, the support plates are nested radially within

the sinking of the plate, which reduces the positioning errors of the elastic return device.

[30] - The depression of the input disc holder plate can be located

radially above the guide bearing;

[31] - Said depression of the plate can be continuous, in order to form a uniform flat support with the common support plate;

[32] - The common support plate of the elastic return device can be

disposed axially opposite the first and second bearing plates, said second bearing plate being able to be disposed radially beyond the first bearing plate;

[33] - The common backing plate can support the first set and the second set of coil springs with different implant diameters. In this way, the different implantation diameters avoid angular misalignment of the coil springs;

[34] - The stampings of the input disc holder plate may be concave or convex and extend axially from said depression of the input disc holder plate;

[35] - The stampings of concave or convex shapes on the plate of the input disc holder may be bosses made on the surface of the plate;

[36] - The stampings of concave or convex shapes of the plate of the input disc holder can form stiffeners, the stiffeners formed also serving as anti-rotation means of the input disc holder; [37] - The stampings of concave or convex shapes of the plate of the input disc holder can be protruding radially and axially;

[38] - The stampings of concave or convex shapes of the input disc holder can be angularly distributed around the X axis;

[39] - For example, the input disc holder deck may have three

stamped with concave or convex shapes distributed at 120 degrees from each other. In another example, the platen of the input disc holder may include four concave or convex stampings distributed at 90 degrees to each other;

[40] - The elastic return device may include rounded openings formed jointly between the first and second support plates, said rounded openings being arranged for the passage of assembly tools;

[41] - The rounded openings are distributed angularly around the X axis, each opening being jointly formed by first and second recesses respectively of the first and second bearing plates.

[42] - The first and second recesses can be formed respectively on the outer periphery of the first support plate and on the inner periphery of the second support plate.

[43] - Advantageously, the elastic return device may include a first axial stop coming from the first support plate and a second axial stop coming from the common support plate, the first and second stops being arranged to limit the crushing of springs;

[44] - The first axial stop may be formed by a folded inner annular flange of the first support plate;

[45] - The second axial stop may be formed by a folded inner annular flange of the common support plate;

[46] - According to a first variant, the anti-rotation means of the elastic return device may be protuberances of convex shapes which fit into the stampings of concave shapes made in the plate of the input disc holders; In this way, the complementary concave - convex shapes are easy to achieve and ensure a better connection by

interlocking between parts. The protuberances provide a greater centering surface of the device with the input disc holder platen.

[47] - The protuberances can be angularly distributed around the X axis;

[48] - For example, the common backing plate may have three

growths distributed at 120 degrees from each other. In another example, the common backing plate may include four protuberances distributed at 90 degrees from each other;

[49] - The protuberances of the common backing plate can be of male shapes complementary to the stampings of the plate of the entry disc holder of female shapes, which reduces interlocking faults between parts;

[50] - The protuberances of the common bearing plate may be rounded in shape;

[51] - The protuberances of the common backing plate may be lugs projecting radially outward.

[52] - The protuberances of the common backing plate can be polygonal in shape. For example, the protuberances can be of the triangular, rectangular, or trapezoidal type;

[53] - The concave shaped stampings of the input disc holder may be grooves;

[54] - Preferably, the concave shaped stampings may have a cross section

substantially rectangular or hollow half-cylinder;

[55] - The concave shaped stampings of the stage may extend radially in the form of bosses extending outwardly of the input disc holder;

[56] - The concave shaped stampings can extend axially over the entire depression of the plate. In other words, the concave shaped stampings can extend axially to the edge of the recess, the rest of the plate of which supports the outer and inner disc holders; [57] - According to a second distinct variant of the first variant, the anti-rotation means of the input disc holder (10) are stampings of convex shapes which fit together in concave shapes made in the plate d common support. In this way, the complementary concave-convex shapes are simple to produce and provide a better connection by interlocking between the parts.

[58] - The convex shaped stampings of the plate may extend radially in the form of bosses made from the outside of the input disc holder and extending towards the X axis;

[59] - For example, the stampings of convex shape can be lugs or teeth;

[60] - Preferably, the stampings of convex shape can be of cross section

substantially in the shape of a hemisphere;

[61] - The convex shaped stampings can extend axially to the position of the second force transmission member, to reduce

the axial size and avoid any interference with the pistons, by defining a maximum safe height of the stampings;

[62] - The concave shapes of the common bearing plate can be

openings, cavities or recesses, of circular or rounded shape;

[63] - For example, the concave shapes of the common backing plate may be openings in the shape of a semi-circle or a half-moon. These simple shapes have the advantage of being easy to produce, which ensures good reproducibility without additional material costs.

[64] - Advantageously, the concave shapes of the common support plate can be produced simply by cutting the outer periphery of the ring, during the same operation of cutting the ring, with the same tools and at no additional cost. manufacturing.

[65] Another subject of the invention, according to a second aspect, is an elastic return device for a wet double clutch, comprising: a first series and a second series of helical springs, each being angularly distributed around an axis X of the device;

- a support plate common to the first and second series of springs, annular in shape, on which anti-rotation means of the elastic return device are formed on the outer periphery of the ring,

wherein anti-rotation means of the elastic return device with respect to the wet double clutch are formed on the outer periphery of the common support plate, said anti-rotation means being arranged to be assembled by interlocking in part of the wet double clutch when the elastic return device is mounted on the wet double clutch.

[66] This elastic return device, according to the invention, has the advantage of reducing the number of components and improving the centering precision of each set of coil springs. The use of a common backing plate eliminates the risk of interference of the first and second backing plates with each other.

[67] The positioning of the anti-rotation means on the outer periphery of the ring improves centering accuracy and limits the residual angular play between the device and the input disc holder. The outer periphery thus performs the functions of centering and anti-rotation of the device on the wet double clutch.

[68] This second aspect of the invention can have either of the

characteristics described below in combination or sockets

independently of each other:

[69] - The second support plate can surround the first support plate; [70] - The second support plate can be disposed radially beyond the first support plate;

[71] - The anti-rotation means of the common support plate can be

stamped and arranged to fit on the part of the wet double clutch;

[72] - The common support plate can be arranged axially opposite the first and second support plates;

[73] - The common backing plate can support the first set and the second set of coil springs with different implant diameters. In this way, the different implantation diameters avoid angular misalignment of the coil springs;

[74] - The elastic return device may include rounded openings formed jointly between the first and second support plates, said rounded openings being arranged for the passage of assembly tools;

[75] - The rounded openings are angularly distributed around the X axis, each opening being jointly formed by first and second recesses respectively of the first and second bearing plates.

[76] - The first and second recesses can be formed respectively on the outer periphery of the first support plate and on the inner periphery of the second support plate.

[77] - Advantageously, the elastic return device can comprise a first axial stop coming from the inner periphery of the first support plate and a second axial stop coming from the inner periphery of the common support plate, the first and the second axial stop. second stops being arranged to limit the crushing of the helical springs;

[78] - The first axial stop may be formed by a folded inner annular flange of the first support plate;

[79] - The second axial stop may be formed by a folded inner annular flange of the common support plate; [80] The invention will be better understood on reading the description which follows, given solely by way of example and made with reference to the appended drawings in which:

[81] [Fig. 1] is an axial sectional view of a wet double clutch according to a first embodiment of the invention;

[82] [Fig. 2] is an exploded perspective view of the input disc holder and the elastic return device for wet double clutch according to the first embodiment of the invention of [Fig. 1];

[83] [Fig. 3] is a front view of the input disc holder and the elastic return device for wet double clutch according to the first embodiment of the invention of [Fig. 1];

[84] [Fig. 4] is a perspective view of the elastic return device alone according to the first embodiment of the invention of [Fig. 1];

[85] [Fig. 5] is a front view of the input disc holder alone according to the first embodiment of the invention of [Fig. 1];

[86] [Fig. 6] is a front view of the input disc holder and the elastic return device for wet double clutch according to a second embodiment of the invention;

[87] [Fig. 7] is a front view of the input disc holder alone according to a

second embodiment of the invention of [Fig. 6];

[88] In the remainder of the description and of the claims, the terms “front” or “rear” will be used without limitation and in order to facilitate understanding thereof in the direction relative to an axial orientation determined by the main axis X of rotation of the transmission of the motor vehicle and the terms “inside / inside” or “outside / outside” with respect to the X axis and in a radial orientation, orthogonal to said axial orientation.

[89] It has been shown in [FIG. 1] a first mode of implementation of a

double wet clutch 1 for torque transmission system. The wet double clutch is of the multi-disc type and has a main axis of rotation X. [90] The wet double clutch 1 comprises around the axis O at least one input element 2 which is connected in rotation to a drive shaft (not shown). The input element 2 is located at the rear of the wet double clutch 1.

[91] In the first embodiment, the input element 2 having an overall shape of an "L", comprises an annular portion of radial orientation formed by an inlet web 3 and an orientation portion axial formed by a hub 4. The input web 3 and the input hub 4 are integral and welded together by laser welding by transparency. The hub 4 is arranged radially on the inside with respect to the inlet web 3.

[92] The input hub 4 is for example linked in rotation by means of the splines 5 at the outlet of a damping device (such as a double damping flywheel, etc.) whose inlet is linked , in particular by means of an engine flywheel, to the driving shaft formed by a crankshaft which is driven in rotation by an engine fitted to the motor vehicle.

[93] The inlet web 3 has, at its radially externally oriented outer end, teeth 9 which extend radially outwardly and which rest on a torque input disc holder 10.

[94] The wet double clutch 1 is controlled to selectively couple said shaft leading to a first driven shaft A1 and to a second driven shaft A2 connected to a gearbox fitted to the motor vehicle.

[95] Preferably, the first driven shaft A1 and the second driven shaft A2 are coaxial. The first driven shaft A1 is driven in rotation when said first clutch E1 is closed and the second driven shaft A2 is driven in rotation when said second clutch E2 is closed.

[96] The wet double clutch 1 comprises a first clutch E1 and a second clutch E2, which are respectively of the multidisc type, as well as a control system 100 arranged to engage or disengage said first and second clutches E1, E2. The control system 100 is attached to a transmission case 150.

[97] As illustrated in Figure 1, the first clutch E1 is arranged

radially above the second clutch E2. [98] The wet double clutch 1 is controlled hydraulically by means of a pressurized fluid, generally oil. The control system 100 comprising:

- A first actuating piston 110 axially movable and arranged to configure the first clutch E1 in a configuration between the engaged configuration and the disengaged configuration;

- a second actuating piston 120 axially movable and arranged to configure the second clutch E2 in a configuration between the engaged configuration and the disengaged configuration;

- A housing 130 in which are housed at least (in part) the first or second actuating piston 1 10, 120;

[99] The first and second clutches E1, E2 are supported on the control system 100 via force transmission members 65, 75.

For example, the actuation system 100 may include an axial extension surface 140 integrated in the housing 130 and extending axially towards the input element 2. The axial extension surface 140 is arranged to support the first and second clutches E1, E2.

[100] In order to reduce the axial compactness, the first force transmission member 65 passes through orifices 19 formed in the input disc holder 10. In addition, the second force transmission member 75 passes through through orifices 20 formed in the input disc holder 10. The orifices 20 formed are disposed radially below the orifices 19 formed.

[101] A guide bearing 80 is disposed between the axial extension surface 140 and the input disc holder 10. More specifically, the guide bearing 80 comprises an outer ring disposed on the inner periphery of the disc holder d 'Input 10. The guide bearing 80 is thus axially resting on the input disk holder 10. The integration of the guide bearing within the input disk carrier 10 allows axial forces to be taken up without altering the 'axial size of the wet double clutch. The guide bearing 80 is thus common to the first and second clutches E1 and E2. For example, the guide bearing 80 is an angular contact ball bearing. The guide bearing 80 is of type ball bearing and rotational guide the first and second clutches E1, E2 relative to the control system 100.

[102] In Figure 1, the first force transmission member 65 is interposed axially between the first clutch E1 and the first actuating piston 110. The second force transmission member 75 is interposed axially between the first clutch E1 and the first actuating piston 120. The first and second force transmission member 65, 75 are movable in translation along the X axis and arranged to selectively control the first and second clutches E1, E2. The elastic return of these actuators is generated by an elastic return device 60.

[103] In the first embodiment of the invention, the wet double clutch 1 comprises an elastic return device 60 making it possible to generate a sufficient axial force by compression to restore the actuating pistons 110, 120 and their clutch. corresponding in their initial so-called disconnected configuration.

[104] The elastic return device 60 comprises a first series of helical compression springs 61, distributed angularly around the X axis and arranged to bear on the first force transmission member 65 by means of a first annular support plate 62. The first support plate 62 of the elastic return device 60 thus supports the first series of helical springs 61 and thus bears on the first force transmission member 65.

[105] The elastic return device 60 also comprises a second series of helical compression springs 71, distributed angularly around the X axis and arranged to bear on the second force transmission member via a second annular support plate 72. The second support plate 72 of the elastic return device 60 supports the second series of helical springs 71 and thus presses on the second force transmission member 75. [106] The second support plate 72 is disposed radially beyond the first support plate 62. More precisely, the second support plate 72 surrounds the first support plate 62.

[107] In particular, the first and second series of helical springs 61, 71 are distinct.

[108] with respect to the first and second support plates 62, 72. As

illustrated in Figure 1, the elastic return device 60 is common to the first actuating piston 110 and the second actuating piston 120.

[109] More specifically, the elastic return device 60 is common to the first force transmission member 65 and to the second force transmission member 75, with which it bears.

[1 10] The first and second series of helical springs 61, 71 are

supported together by a common part, here a ring, so that the series of coil springs 61, 71 as well as the first and second annular backing plates 62, 72 do not overlap or interfere with each other.

[1 1 1] This common part is a common support plate 17 of the form

annular, which connect the first and second series of helical springs 61, 71 to each other, as illustrated in particular in Figures 2 to 4.

[1 12] The common support plate 17 is arranged axially facing the

first and second backing plates 62, 72. The common backing plate 17 supports the first set and the second set of coil springs 61, 71 at different implant diameters. In this way, the different implantation diameters avoid angular misalignment of the coil springs 61, 71.

[1 13] In the first embodiment of the invention, the elastic return device 60 is supported on the torque input disc holder 10.

[1 14] The torque input disc holder 10 is common to the first and the

second clutch E1 and E2. The input disc holder 10 comprises an outer disc holder 14 of the first clutch E1 and an inner disc holder 24 of the. second clutch E2. Advantageously, the inner disc holder 24 of the second clutch E2 is welded or riveted to the input disc holder 10.

[1 15] In particular, the elastic return device 60 is fitted inside the input disc holder 10, so as to couple the two parts in rotation.

[1 16] The input disc holder 10 further comprises a plate 34 made of sheet steel. The platen 34 of the input disc holder 10 extends radially from the X axis and jointly supports the outer and inner disc holders.

[1 17] The plate 34 of the input disc holder 10 comprises on its inner periphery a shoulder 16 of annular shape. The shoulder 16 of the plate 34 is a cylindrical bearing portion and forms an internal volume suitable for receiving the guide bearing 80, and more precisely the outer ring of the guide bearing 80.

[1 18] The plate 34 of the input disc holder 10 also includes on its

internal periphery a depression 15 of annular shape. The recess 15 of the plate 34 which is located radially below the inner disc holder 24. The recess 15 of the plate 34 is located radially above the guide bearing 80, as illustrated in Figure 1. In other words , the indentation 15 formed in the input disc holder 10 is arranged over a diameter located beyond the shoulder 16 of the plate 34. The indentation 15 of the plate 34 of the input disc holder 10 is continuous, in order to form a uniform flat support with the common support plate 17.

[1 19] The elastic return device 60 is in particular housed in this recess 15 of the plate 34. More specifically, the common support plate 17 bears on the plate 34 of the input disc holder 10 at the level of this

recess 15. The support plates 62, 72 are nested radially within the recess 15 of the plate 34, in order to reduce the defects of

positioning of the elastic return device 60.

[120] In the first embodiment of the invention, the elastic return device 60 and the input disk holder 10 are thus fitted together and coupled in rotation, by means of anti-rotation means. 81, 82. [121] As illustrated in Figures 1 to 5, these anti-rotation means 81, 82 are formed respectively on the elastic return device 60 and on the input disc holder 10. The assembly of the means of anti-rotation 81, 82 forms a connection by interlocking between the elastic return device 60 and the input disc holder 10. The interlocking connection ensures the indexing and angular positioning of the elastic return device 60 relative to the door -disks 10, which prevents any rotation of the elastic return device 60 during its operation on the vehicle. The interlocking assembly of the anti-rotation means 81, 82 can be carried out manually, without any deformation and without any special tools.

[122] In the first embodiment of the invention, the elastic return device 60 thus comprises anti-rotation means 81. The anti-rotation means 81 of the elastic return device 60 are formed on the outer periphery 18 of the common annular bearing plate 17.

[123] In our example illustrated in particular in Figures 2 to 4, the anti-rotation means 81 of the elastic return device 60 are concave shapes 91 of the common support plate 17. Advantageously, the concave shapes 91 of the common support plate 17 are openings, cavities or recesses, of circular or rounded shapes.

[124] In particular in Figure 4, the concave shapes 91 of the common support plate 17 are openings in the shape of a semi-circle or a half-moon. These simple shapes 91 have the advantage of being easy to produce, which ensures good reproducibility, without additional material costs.

[125] Advantageously, the concave shapes 91 of the common support plate 17 are made simply by cutting out its outer periphery 18, during the same ring cutting operation, with the same tools and without additional manufacturing costs. In a variant not shown, the anti-rotation means 81 of the common backing plate may be stamped and arranged to adapt to the shape of the stampings of the input disc holder.

[126] In the first embodiment of the invention, the disc holder

annular inlet 10 thus comprises anti-rotation means 81. The means anti-rotation 82 of the input disc holder 10 are formed by stamping sheet steel from the platen of the input disc holder 10.

[127] In particular, the anti-rotation means 82 of the input disc holder 10 are formed radially below the inner disc holder 24. The anti-rotation means 82 of the plate 34 of the disc holder d 'inlet 10 are formed radially beyond the shoulder 16, without altering the axial size of the wet double clutch. In a variant not shown, the anti-rotation means 82 of the input disc holder may be formed radially on the internal diameter of the plate of the input disc holder.

[128] In the first embodiment of the invention, the stampings of the plate 34 of the input disc holder 10 are the stamps of convex shapes 94. The stamps of convex shapes 94 thus fit into concave shapes 91 produced in the common support plate 17 of the elastic return device 60. In this way, the complementary concave-convex shapes are simple to produce and provide better interlocking connection between the parts.

[129] The stampings of convex shapes 94 of the plate 34 of the record holder

input 10 are angularly distributed around the X axis. In the example illustrated in particular in FIGS. 2 to 5, the plate 34 of the input disc holder 10 comprises four convex stampings 94 distributed at 90 degrees to each other. others. In another example not shown, the plate 34 of the input disc holder may include three stampings of concave or convex shapes distributed at 120 degrees from each other.

[130] The convex shaped stampings 94 extend axially from said recess 15 of the plate 34 of the input disc holder 10. The convex shaped stampings 94 of the plate 34 of the input disc holder 10 of. entrance are prominent radially and axially.

[131] As illustrated in particular in Figures 2, 3 and 5, the stampings of convex shapes 94 of the plate 34 of the input disc holder 10 are bosses made on the surface of the plate 34. More specifically, the stamped convex shapes 94 of the plate 34 extend radially in the form of bosses made from outside the input disc holder 10 and extending towards the X axis.

[132] Advantageously, the convex shaped stampings 94 are here lugs or teeth. Preferably, the convex-shaped stampings 94 are of section substantially in the shape of a hemisphere.

[133] In particular, the convex shaped stampings 94 of the plate 34 of the input disc holder 10 form stiffeners, the formed stiffeners also serving as anti-rotation means 82 of the input disc holder 10.

[134] A lubricating ring 50 is also disposed radially between the axial extension surface 140 and the input disc holder 10. The lubricating ring 50 bears axially on the guide bearing 80.

[135] The lubrication ring 50 includes lubrication ducts 51

crossing radially right through the ring and opening onto the outer periphery. The lubrication ducts 51 are oriented radially in the direction of the clutches E1 and E2. Advantageously, the lubrication conduits 51 are at least partially open laterally. In this case, the ducts 51 are then delimited jointly by the clutch support and another component part of the wet double clutch, such as here for example the guide bearing.

[136] In Figure 1, the lubricating ring 50 is retained axially by a threaded portion capable of being screwed onto a complementary threaded portion of the support 140 of the wet double clutch, more precisely on the free end of the support. In this way, in an assembled state, the wet double clutch and the actuation system are fixed integrally by means of a threaded connection in which the lubricating ring 50 is screwed directly onto the axial extension surface. 140 of the housing 130.

[137] In a variant not shown, the lubricating ring 50 can also be

retained axially by a split ring fitted in a groove provided on the axial extension surface of the housing.

[138] The casing 130 of the control system 100 comprises ducts

coolant supply 131 which communicate directly with the lubrication conduits 51. The lubrication ring 50 thus channels the cooling fluid from the actuation system 100 towards the first and second clutches E1, E2 and promotes their

lubrication.

[139] As illustrated in Figure 1, the multi-disc assembly of the first clutch E1 comprises flanges 11 connected in rotation to the input disc holder 10 and friction discs 12 connected in rotation to a first output disc holder 30 of torque. The friction discs 12 are, individually, axially interposed between two successive flanges January 1.

[140] The torque output disc holder 30 of the first clutch E1 is rotatably linked by meshing with the friction discs 12 and by a splined connection with said first driven shaft A1. The output disc holder 30 includes an output hub 31 connected to the driven shaft A1.

[141] The multi-disc assembly of the second clutch E2 includes flanges 21 rotatably linked to the input disc holder 10 and friction discs 22 rotatably linked to a second torque output disc holder 40.

[142] The torque output disk holder 40 of the second clutch E2 is rotatably linked by meshing with the friction discs 22 and by a splined connection with said second driven shaft A2. The output disc holder 40 includes an output hub 41 connected to the driven shaft A2.

[143] The outer disc holder 14 of the first clutch E1 in particular comprises an axial extension arranged to receive the multi-disc assembly of the first clutch. The axial extension forms an internal groove receiving the flanges 11 of the multidisc assembly of the first clutch E1.

[144] The inner disc holder 24 of the second clutch E2 comprises a

axial extension arranged to receive the multi-disc assembly of the second clutch. The axial extension forms an internal groove receiving the flanges 21 of the multidisc assembly of the second clutch E2.

[145] In order to reduce the axial size of the wet double clutch 1, the first and second clutches E1, E2, the elastic return device 60 and the Guide bearing 80 are concentric and are nested radially within the input disc holder 10.

[146] In order to reduce axial compactness, the first force transmission member 65 passes through orifices 76 formed in the second force transmission member 75 to press on the first elastic return device. The first force transmitting member 65 includes support legs 66 formed on its inner periphery. The support legs 66 are angularly distributed around the axis O and thus pass through through the orifices 76 of the second force transmission member.

[147] In the first embodiment, the elastic return device 60 further comprises openings 70 rounded and formed jointly between the first and second support plates 62, 72.

[148] As illustrated in particular in Figures 2 and 4, the openings 70

rounded are distributed angularly around the X axis. The rounded openings 70 are arranged for the passage of an assembly tool of the elastic return device 60 on the input disc holder 10.

Advantageously, each rounded opening 70 is jointly formed by first and second recesses 63, 73 respectively of the first and second support plates 62, 72.

[149] Preferably, the first recesses 63 are formed on the periphery

outside of the first backing plate 62. Preferably, the second recesses 73 are formed on the inner periphery 18 of the second backing plate 72.

[150] Finally, the elastic return device 60 comprises a first axial stop 64 which comes from the inner periphery of the first support plate 62. The elastic return device 60 also comprises a second axial stop 74 which comes from the inner periphery of the common support plate 17. Advantageously, the first and second stops 64, 74 are arranged to limit the crushing of the helical springs 61.

[151] As illustrated in particular in Figures 2 and 4, the first axial stop 64 is formed by a folded inner annular flange of the first support plate 62. Preferably, the second axial stop 74 is formed by a folded inner annular rim of the common support plate 17.

[152] In a variant not shown, the first and second annular plates 62, 72 can be retained axially on the common support plate by latching means. The snap-fit means may include folded tabs formed on the common backing plate. These folded legs can be inserted into complementary housings formed on the first and second support plates.

[153] There has been described in Figures 6 to 7, a second embodiment of the invention substantially similar to the first embodiment, except for the fact that the anti-rotation means 81 of the elastic return device 60 are protuberances 90 of convex shapes, and that the anti-rotation means 82 of the input disc holder 10 are stampings of concave shapes 93.

[154] Advantageously, the protuberances 90 fit into the stampings of concave shapes 93 made in the plate 34 of the input disc holder 10. In this way, the protuberances 90 provide a greater centering surface for the return device. elastic 60 with the plate 34 of the input disk holder 10. In particular for this second embodiment, the protuberances 90 of the common support plate 17 are of male shapes complementary to the stampings 93 of female shapes of the plate 34 of the input disc holder 10, which reduces interlocking faults between parts.

[155] In this second embodiment of the invention, the protuberances 90 of the elastic return device 60 are angularly distributed around the axis X. In the example illustrated in particular in Figures 2 to 5, the common support plate 17 of the elastic return device 60 comprises four protuberances 90 distributed at 90 degrees from each other. In another example, not shown, the common support plate may include three protuberances distributed at 120 degrees from each other.

[156] The protuberances 90 of the common support plate 17 are of rounded shapes. Preferably, the protuberances 90 of the common bearing plate 17 are lugs projecting radially outwards from the elastic return device 60.

[157] Advantageously, the protuberances 90 of the common support plate 17 are of polygonal shapes. For example, the protuberances 90 are of the rectangular type. In a variant not shown, the protuberances 90 may be of the triangular or trapezoidal type.

[158] In this second embodiment of the invention, the stampings of concave shapes 93 of the plate 34 of the input disc holder 10 are distributed angularly around the axis X. In our example illustrated in particular in Figures 6 to 7, the plate 34 of the input disc holder 10 comprises four concave stampings 93 distributed at 90 degrees from each other. The concave shaped stampings 93 of the plate 34 of the input disc holder 10 are bosses made on the surface of the plate 34.

[159] The stampings of concave shapes 93 of the plate 34 of the record holder

inlet 10 are radially and axially prominent.

[160] The concave shaped stampings 93 extend axially from said

depression 15 of the plate 34 of the input disc holder 10. As illustrated in particular in FIG. 7, the concave shaped stampings 93 of the plate 34 extend radially in the form of bosses extending outwardly of the holder - input disks.

[161] The concave shaped stampings 93 of the input disc holder 10 extend axially over the entire recess 15 of the plate 34. In other words, the concave shaped stampings 93 extend axially up to edge

the recess 15 of which the rest of the plate 34 supports the outer 14 and inner 24 disc holders.

[162] Advantageously, the concave shaped stampings 93 of the disc holder

entry 10 are grooves. Preferably, the concave shaped stampings 93 are of substantially rectangular section or of hollow half-cylinder.

[163] In particular, the embossed concave shapes 93 of the plate 34 of the input disc holder 10 form stiffeners, the stiffeners formed also serving as anti-rotation means 82 of the input disc holder 10. [164] Of course, the present invention is not limited to the embodiments described and shown, provided by way of illustrative and non-limiting example.

Claims

[Claim 1] Wet double clutch (1) for a motor vehicle, comprising:

- a first clutch (E1) and a second clutch (E2)

respectively of multidisc type rotating around an axis (X), controlled to selectively couple a shaft leading to a first driven shaft (A1) and to a second driven shaft (A2) by means of a disc carrier d 'common torque input (10), the first clutch (E1) being disposed radially beyond the second clutch (E2),

- a first member and a second force transmission member (65, 75) arranged to control the first and second clutches (E1, E2), and

- an elastic return device (60) of the first member and of the

second force transmission member (65, 75) resting on the input disc holder (10),

characterized in that said elastic return device (60) is common to the first member and to the second force transmission member (65, 75),

said elastic return device (60) and said input disk holder (10) being coupled in rotation by anti-rotation means (81, 82), said anti-rotation means (81, 82) forming a connection by interlocking.

[Claim 2] A wet double clutch (1) according to claim 1, wherein the elastic return device (60) comprises:

- a first series and a second series of helical springs (61, 71), each being angularly distributed around the X axis);

- a first support plate (62) supporting the first series of

coil springs (61) and pressing on the first force transmitting member (65);

- a second support plate (72) supporting the second series of helical springs (71) and pressing on the second force transmission member (75); and, - a common support plate (17) to the first and second series of springs (61, 71), of annular shape, on which anti-rotation means (81) of the elastic return device (60) are formed on the outer periphery (14) of the ring.

[Claim 3] Wet double clutch (1) according to the preceding claim, in which the common bearing plate (17) of the elastic return device (60) is disposed axially opposite the first and second bearing plates (62, 72).

[Claim 4] A wet double clutch (1) according to any one of claims 2 to 3, wherein the common backing plate (17) supports the first set and the second set of coil springs (61, 71) on different implantation diameters, said second support plate (72) being disposed radially beyond the first support plate (62).

[Claim 5] A wet dual clutch (1) according to any preceding claim, wherein the input disc carrier (10) comprises:

- an outer disc holder (14) of the first clutch (E1);

- an internal disc holder (24) of the second clutch (E2);

- a plate made of sheet steel extending radially with respect to the X axis jointly supporting the outer (14) and inner (24) disc holder, on which anti-rotation means (82) of the holder - input discs (10) are formed by stamping.

[Claim 6] Wet double clutch (1) according to the preceding claim, wherein the anti-rotation means (81) of the elastic return device (60) are protuberances (90) of convex shape which

fit into concave shaped stampings (93) made in the platen (34) of the input disc holder (10).

[Claim 7] A wet double clutch (1) according to claim 5, wherein the anti-rotation means of the input disc carrier (10) are convex shaped stampings (94) which interlock into shapes. concaves (91) made in the common support plate (17).

[Claim 8] A wet double clutch (1) according to claim 5, wherein the common backing plate (17) of the spring return device (60) rests on the plate (34) of the input disc holder (10) at the level of an annular-shaped recess (15) located radially below the inner disc holder (24).

[Claim 9] A wet double clutch (1) according to claim 6, wherein the concave shaped stampings (93) of the input disc carrier (10) are angularly distributed around the X axis.

[Claim 10] A wet double clutch (1) according to claim 7, wherein the convex shaped stampings (94) of the input disc carrier (10) are angularly distributed around the X axis.

[Claim 1 1] Double wet clutch (1) according to any one of the preceding claims 2 to 10, in which the elastic return device (60) comprises a first axial stop (64) coming from the inner periphery of the first plate support (62) and a second axial stop (74) issuing from the inner periphery of the common support plate (72), the first and second stops (64, 74) being arranged to limit

the crushing of the coil springs (61).

[Claim 12] An elastic return device for a wet double clutch, comprising:

- a first support plate (62) supporting the first series of

coil springs (61) and pressing on the first force transmitting member (65);

- a second support plate (72) supporting the second series of helical springs (71) and pressing on the second force transmission member (75); and,

- a common support plate (17) to the first and second series of springs (61, 71), of annular shape, on which anti-rotation means (81) of the elastic return device (60) are formed on the outer periphery (14) of the ring,

in which anti-rotation means of the elastic return device with respect to the wet double clutch are formed on the outer periphery of the common bearing plate, said anti-rotation means being arranged to be assembled by interlocking in a part of the wet double clutch when the elastic return device is mounted on the wet double clutch.