FR3115081A1 - “ELASTIC RETURN DEVICE FOR CLUTCH SYSTEM” - Google Patents

Abstract

ELASTIC RETURN DEVICE FOR CLUTCH SYSTEM The invention relates to an elastic return device (50) for a clutch system, of axis X of revolution, comprising: – a common support plate (30), – a first support plate (10), and at least two first groups (11) of springs (100) positioned between the common support plate (30) and the first support plate (10), – a second support plate (20), and at least a second group (21) of springs (200) positioned between the common support plate (30) and the second support plate (20). Figure for abstract: FIGURE 2

Description

“ELASTIC RETURN DEVICE FOR CLUTCH SYSTEM”

The present invention relates to an elastic return device for a clutch system, as used for a vehicle transmission. The invention also relates to a clutch system, such as for example a double or a triple wet clutch, comprising such an elastic return device.

There are known clutch systems comprising for example a first and a second wet clutch as well as a first and a second actuator generating a force to respectively configure the first and the second clutch in an engaged or disengaged configuration. The force generated by each actuator is transmitted to the corresponding clutch via a force transmission member which, in turn, moves first friction elements relative to second friction elements of the clutch , to configure the clutch in one or other of the configurations mentioned.

In known manner, if an actuator is implemented in order to push the force transmission member, the retrograde movement of the actuator is exerted by an elastic washer generating a sufficient force to restore the actuator and the corresponding clutch in their initial configuration says disengaged. This elastic washer, generally made of the Belleville washer type, is inserted between a clutch plate carrier and the power transmission member. It is possible to replace the elastic washer by elastic return means made in the form of helical compression springs.

This elastic return device is known for an application on a simple clutch, comprising first and second annular support plates, and helical springs arranged circumferentially and regularly between the first and second support plates. As part of a double wet clutch system, it is known from document DE102015222191 A1 to have two elastic return devices of the aforementioned type, between a disc carrier and the two force transmission members of the corresponding clutches. In order to reduce the axial size of the double clutch system, the two elastic return devices can be assembled one inside the other concentrically. These two devices, one inside the other, can for example be offset or come into interference.

But this architecture is not entirely satisfactory and has drawbacks, in particular a complex and cumbersome assembly, geometrical defects of alignment and centering of the plates supporting the springs. Complex shapes are necessary for the force transmission members in order to mount them on their elastic return device.

The object of the invention is to respond, at least in large part, to the above problems and also to lead to other advantages. The object of the invention is in particular to provide a simple, effective and economical solution to this problem.

For this purpose, the invention proposes, according to a first aspect, an elastic return device for a clutch system, of axis X of revolution, comprising:
– a common support plate,
– a first support plate, and at least two first groups of springs positioned between the common support plate and the first support plate,
- a second support plate, and at least a second group of springs positioned between the common support plate and the second support plate.

According to these characteristics, the space lost between the springs is reduced, by grouping them together in the form of first and second (s) groups of springs, unlike a circumferential and regular distribution of springs known in the prior art. The bulk of the springs and support plates is reduced in the radial and circumferential direction. The dimensions of the support plates as well as those of the common support plate for the springs are also reduced.

Such an elastic return device has the advantage of being arranged in a greatly reduced space radially, within the clutch system, to elastically return two force transmission members.

Moreover, the elastic return can be concentrated at the level of the first groups of springs. The first bearing plate and the first groups of springs therefore compactly form the first elastic return intended to support a first force transmission member. The second support plate and the first group(s) of springs also compactly form a second elastic return intended to support a second force transmission member. The use of a common support plate for the springs eliminates the risk of the support plates interfering with each other.

By "clusters" of springs is meant a distinction in the distribution of the springs around the X axis, including a concentration of springs in certain appropriate areas of the backing plate. A group of springs includes at least two springs having one or more common characteristics (height, installation diameter, etc.). Two groups of springs must be spaced and distant from each other, and in an optimized way.

• « avant » ou « arrière » selon la direction par rapport à une orientation axiale déterminée par l’axe principal de rotation du porte-disques, « l’arrière » désignant la partie située à droite des figures, du côté de la transmission, et « l’avant » désignant la partie gauche des figures, du côté du moteur ; et
• « intérieur / interne » ou « extérieur / externe » par rapport à l’axe de rotation et suivant une orientation radiale, orthogonale à ladite orientation axiale, « l’intérieur » désignant une partie proximale de l’axe de rotation et « l’extérieur » désignant une partie distale de l’axe de rotation.

In the remainder of the description, the terms will be used, without limitation and in order to facilitate understanding thereof:

• "front" or "rear" depending on the direction with respect to an axial orientation determined by the main axis of rotation of the disc carrier, "the rear" designating the part situated to the right of the figures, on the side of the transmission, and “the front” designating the left part of the figures, on the engine side; And
• "inside/internal" or "outside/external" with respect to the axis of rotation and following a radial orientation, orthogonal to the said axial orientation, the "inside" designating a proximal part of the axis of rotation and "the exterior” designating a distal part of the axis of rotation.

The elastic return device, in accordance with the first aspect of the invention, advantageously comprises one or more improvements described below, these technical characteristics forming these improvements being able to be taken alone or in combination:

– The number of springs of a first group of springs can be between three and thirty-five springs, in particular between fifteen and twenty-five springs per group. The first groups of springs can be identical, for example with the same number of springs. Alternatively, at least two first groups may comprise a different number of springs;

– The number of springs of a second group of springs can be between three and thirty-five springs, preferably between fifteen and twenty-five springs per group. The second groups of springs can be identical, for example with the same number of springs. Alternatively, at least two second groups may comprise a different number of springs;

- The number of first groups of springs can be between two and fifteen first groups, for example between three and ten "first" groups. The total number of first groups of springs may be even, or alternatively, odd;

– The first groups of springs can be nested in the second support plate;

– The at least one second group of springs can be nested in the first bearing plate;

– Advantageously, at least part of a second group of springs is arranged between two first groups of immediately adjacent springs. In other words, at least one of the springs of said at least one second group of springs can be arranged between two immediately adjacent first groups of springs, in order to further reduce the bulk between the springs;

– Advantageously, the elastic return device may comprise a plurality of second groups of springs;

- In particular, the number of second (s) group (s) of springs can be between one and fifteen second group (s), for example between two and ten "second" groups. The total number of second groups of springs can be odd or even.

– In such a situation, the first and second groups of springs can be distributed alternately around the X axis. For example, the first and second groups of springs can be staggered, in other words, alternately on two circles or diameters for installing springs, for example one by one, or even two by two;

– Advantageously, the first groups of springs can be arranged along an implantation diameter different from that of the springs of the second group(s), the advantage being to avoid angular misalignment of the springs and to simplify the arrangement of the corresponding force transmission components;

– Alternatively, the first and second groups of springs can be arranged on a similar installation diameter. Consequently, the force transmission components are arranged and nested at the level of the same diameter of installation of the springs, reducing their size;

– The springs of the first and second group(s) are of identical shapes, such as for example springs of the same stiffness, of the same diameter and/or of the same height. The assembly of the various springs is thus simplified and standardized.

– For example, the same height of springs can advantageously allow the two support plates to be arranged coplanar, one facing the other;

– Alternatively, the springs of the first groups are of different shapes from those of the second group(s). By way of example, the springs of a first group can have different stiffnesses, heights or diameters from those of a second group, to form different elastic returns between the two force transmission members, as required.

– Advantageously, the first bearing plate and the second bearing plate can be arranged axially on the same side of the common bearing plate;

– For example, the first backing plate can surround the second backing plate. As a variant, the second support plate can surround the first support plate, in order to limit the axial size of the elastic return device;

– In another example, the first support plate can be arranged axially between the second support plate and the common support plate, so as to further limit the radial size of the elastic return device;

– Advantageously, the common support plate may comprise bosses adapted to receive at least one spring from a first group and/or from a second group of springs. In particular, bosses can receive an entire first group and/or an entire second group of springs;

– Advantageously, the first bearing plate may be of complementary shape to that of the second bearing plate;

– Advantageously, a radial elongation of the first bearing plate can extend variably around the X axis. In particular, the radial elongation of the first bearing plate can extend a distance variable around the axis;

– Alternately or additionally, a radial elongation of the second bearing plate can extend variably around the X axis.

– In particular, the radial elongation of the second bearing plate can extend to a variable distance around the axis;

– Preferably, the radial elongation of the first backing plate may range between 55% and 100% of a common backing plate radial elongation, for example, between 65% and 95% of the radial elongation of the common backing plate;

– Preferably, the radial elongation of the second backing plate can range between 55% and 100% of a common backing plate radial elongation, for example, between 65% and 95% of the radial elongation of the common backing plate.
The advantage of such dimensions of the support plate(s) makes it possible to optimize the arrangement and the space of each support plate on the common support plate, to reduce the bulk within the elastic return device ;

– Advantageously, cutouts can be formed on the radially inner or radially outer periphery of the first bearing plate, the springs of the at least one second group passing through said cutouts;

– Alternately or additionally, cutouts may be formed on the radially inner or radially outer periphery of the second support plate, the springs of a first group passing through said cutouts. By “cutting out” of a plate is meant an opening made for the passage of one or a plurality of springs of a group of springs;

– In particular, the cutouts can be open or closed shapes. For example, each cutout may have an open-type contour, on the radially internal or radially external periphery of said bearing plate;

– In another example, each cutout may have a closed-type outline, arranged on the radially inner or radially outer periphery of said bearing plate, or even in the center of said bearing plate;

– Preferably, a cutout can receive a first or second entire group of springs. In this way, the number of cutouts is limited and they are sized according to a number of springs per group;

– Advantageously, the cutouts of a support plate can be identical to each other, in order to evenly distribute the groups of springs and/or to have an identical number of springs pass through each cutout. Advantageously, the shape of the cutouts of the first support plate can be identical to that of the cutouts of the second support plate;

– The cutouts of the first plate and/or of the second support plate can be distributed angularly around the X axis. The cutouts can be distributed over the radially inner or radially outer perimeter of a support plate;

– Support portions of the first support plate can support the springs of the first groups, said support portions of the first support plate being of complementary shape to that of the cutouts of the second support plate.

– Alternately or additionally, bearing portions of the second bearing plate can support the springs of said at least one second group, said bearing portions of the second bearing plate being of complementary shape to that of the cutouts of the first bearing plate. “Support portion” means the part of the support plate supporting the springs and delimited between two adjacent cutouts made on this same plate;

– Advantageously, the cutouts of the first support plate and the second support plate can be distributed alternately around the X axis, for example staggered.

– The support portions of the first support plate and of the second support plate can be distributed alternately around the X axis, for example arranged in staggered rows, for example one by one;

– In particular, a support portion of a plate supports an entire group of springs, the advantage being to define the dimensions of a solid portion according to the total number of springs of a first group of springs that it supports ;

– The total number of solid portions, respectively of a first and/or a second plate, is defined according to the number of groups of springs, respectively that of the first and/or second groups of springs;

– The support portions of a support plate can be distributed over the radially inner or radially outer periphery of said support plate. The support portions of a support plate can be distributed angularly around the X axis;

– The remaining support portions of the first support plate and/or the second support plate may be identical;

– Preferably, each cutout, respectively each support portion, of the first support plate may have a shape complementary to that of the support portion, respectively of the cutout, of the second support plate. The advantage is to guarantee an interweaving of shapes between the support plates reducing the size of said elastic return device;

– The first bearing plate may have on its radially inner periphery, respectively on its radially outer periphery, an alternation of cutouts and bearing portions;

– The second support plate may have on its radially outer periphery, respectively on its radially inner periphery, an alternation of support portions and cutouts;

The invention also relates, according to a second aspect, to a wet clutch system intended to be integrated into a transmission chain, comprising
– at least a first clutch and a second clutch respectively of the multi-disc type, controlled to selectively couple a driving shaft to a first driven shaft and to a second driven shaft,
– a torque input disc carrier supporting the first and second clutches,
– at least a first member and a second force transmission member arranged to respectively control the first clutch (E1) and second clutch,
characterized in that it comprises a common elastic return device of the first and second force transmission members according to any one of the preceding characteristics, said elastic return device resting on the input disc carrier.

According to these characteristics, such a clutch system is of the compact type. The arrangement of the groups of springs makes it possible to reduce the overall dimensions of the components. This creates a free space inside the system, in particular for arranging other components within the clutch system. The number of parts required is also reduced, the elastic return device being common to the first and second force transmission members.

The elastic return device forms a unitary sub-assembly which facilitates handling by the operator. The input disc carrier and the two force transmission members can thus be of reduced dimensions.

Preferably, the common support plate can rest on the input disc carrier.

• un porte-disque extérieur du premier embrayage,
• un porte-disque intérieur du deuxième embrayage,
• une platine s’étendant radialement par rapport à l’axe X et supportant conjointement les porte-disques extérieur et intérieur, sur laquelle ledit dispositif de rappel élastique est en appui.

L’avantage d’une telle platine est d’assurer une imbrication dudit dispositif de rappel élastique radialement au sein de l’enfoncement, afin de réduire les défauts de positionnement des plaques du dispositif de rappel élastique.Advantageously, the entry disc carrier can include:

• an outer disc carrier of the first clutch,
• an inner disc carrier of the second clutch,
• a plate extending radially with respect to the axis X and jointly supporting the outer and inner disc carriers, on which said elastic return device bears.

The advantage of such a plate is to ensure an interlocking of said elastic return device radially within the depression, in order to reduce the positioning faults of the plates of the elastic return device.

Preferably, the plate of the input disc carrier comprises a ring-shaped recess located radially below the inner disc carrier. Such sinking of the plate is reduced and optimized thanks to the arrangement of the first and second groups of springs, as well as the support plates. Specifically, the common support plate rests on the plate of the input disc carrier, in particular, on the depression of the plate.

The invention will be better understood on reading the following description, given solely by way of example and made with reference to the appended drawings in which:
- There is an axial section of a clutch system according to a first embodiment of the invention;
- There is a perspective view of the elastic return device according to the first embodiment of [Fig. 1];
- There is a perspective view of the elastic return device according to a second embodiment of the invention;
- There is a perspective view of the elastic return device according to a third embodiment of the invention;
- There is a perspective view of the elastic return device according to a fourth embodiment of the invention;

In the remainder of the description and the claims, the terms “front” or “rear” will be used, without limitation and in order to facilitate understanding, depending on the direction with respect to an axial orientation determined by the main axis X of rotation of the transmission of the motor vehicle and the terms "inner/inner" or "outer/outer" with respect to the X axis and in a radial orientation, orthogonal to said axial orientation. Unless otherwise indicated, the verbs "include", "present" or "understand" must be interpreted broadly, that is to say not limiting.

The term "vehicle" means motor vehicles, including not only passenger vehicles, but also industrial vehicles, in particular heavy goods vehicles, public transport vehicles or agricultural vehicles, but also any transport vehicle allowing the passage from one point to another a living being and/or an object.

Unless otherwise specified, “axially” means “parallel to the axis X of rotation of the elastic return device or of the clutch system”; "radially" means "along a transverse axis intersecting the axis of rotation of the clutch system"; “Angularly” or “circumferentially” means “around the X axis of rotation of the clutch system”. The thickness is here measured along the X axis of rotation.

There is shown in FIGURES 1 to 2 a first embodiment of a wet clutch system 1 for torque transmission, within a torque transmission chain of a motor vehicle, via a casing gearbox fitted with two driven torque output shafts A1, A2.

The clutch system 1 is here a double wet clutch, of the multi-disc type, and it has a main axis of rotation X. As a variant not shown, the clutch system 1 can be a triple clutch or hybrid clutch, intended to equip automatic, robotic, hybrid and/or electric transmissions of a motor vehicle.

The clutch system 1 thus comprises a first clutch E1 and a second clutch E2, which are respectively of the multi-disc type, respectively of the multi-disc type, controlled to selectively couple a motor, for example a heat engine and a rotating electric machine M, to a first driven shaft A1 and a second driven shaft A2. In the example illustrated, the first and second clutches E1, E2 are arranged radially one above the other along the axis X. This arrangement of the clutches E1, E2 can of course be reversed.

The clutch system 1 is controlled to selectively couple said driving shaft to a first driven shaft A1 and to a second driven shaft A2 connected to a gearbox fitted to the motor vehicle. The torque from the combustion engine and the electric motor can then be transmitted to the coaxial shafts A1, A2 of the gearbox depending on the closing of one or the other of the first clutch E1 or of the second clutch E2. 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. 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.

The clutch system 1 comprises a control system 90 arranged to engage or disengage said first and second clutches E1, E2. Control system 90 is preferably attached to transmission housing 150.

The clutch system 1 also comprises around the axis X at least one torque input element 2 which is connected in rotation to a drive shaft (not shown). The input element 2 is located at the rear rear of the clutch system 1. In the example illustrated, the input element 2 generally having an "L" shape, comprises an annular portion of orientation radial formed by an inlet veil 3 and an axial orientation part formed by a hub 4.

The torque input veil 3 and the torque input hub 4 are integral and welded together, for example by laser welding by transparency. The input veil 3 comprises, at its outer radial end of axial orientation, teeth 9 which extend radially outwards and which rest on a torque input disk carrier 40.

The input hub 4 is arranged radially inside with respect to the input veil 3. The input hub 4 is for example linked in rotation via the splines 5 to the output of a damping device (such as a double damped flywheel, etc.) whose input is linked, by the intermediary in particular of a flywheel, to the drive shaft formed by a crankshaft which is driven in rotation by an engine fitted to the motor vehicle.

The clutch system 1 is hydraulically controlled by means of a pressurized fluid, generally oil. The 90 control system includes:
- a first actuating piston 110, arranged to configure the first clutch E1 in a configuration between the engaged configuration and the disengaged configuration;
- a second actuating piston 210, arranged to configure the second clutch E2 in a configuration between the engaged configuration and the disengaged configuration;
– a casing 130 in which are housed at least (in part) the first or the second actuating piston 110, 210.

The first and second clutches E1, E2 bear against the control system 90 via force transmission members 60, 70. For example, the actuation system 1 can comprise an axial extension bearing 140 integrated in the casing 130 and extending axially in the direction of the input element 2. The axial extension bearing surface 140 is arranged to support the clutches E1, E2.

The input disk carrier 40, common to the clutches E1, E2, is made up of an outer torque input disk carrier 41, an inner disk carrier 42 and a central plate 45 integrally linked together. in rotation. The axial extension of the outer disc carrier 41 supports the multi-disc assembly of the first clutch E2. The axial extension of the inner disc carrier 42 supports the multi-disc assembly of the second clutch E2.

In the context of the invention, the first and second clutches E1, E2 are arranged so as not to be simultaneously in the same clutched configuration. On the other hand, the first clutch E1 and the second clutch E2 can simultaneously be configured in their disengaged position. The multi-disc assembly of the first clutch E1 comprises an alternation of friction discs, such as for example flanges 7 linked in rotation by meshing with the outer disc carrier 41, and on the other hand friction lining discs 8 linked in rotation to a first torque output 43 disc carrier.

Similarly, the multi-disc assembly of the second clutch E2 comprises alternating flanges 7', connected in rotation to the inner disk carrier 48, and friction lining disks 8', connected in rotation to a second output disk carrier 44 torque. The axial force generated by the force transmission members makes it possible to push the flanges 7, 7' axially against the discs 8, 8' of the friction linings of the corresponding clutch, in order to couple them in rotation.

The plate 45 comprises on its internal periphery a shoulder of annular shape. The shoulder of the plate 45 is a cylindrical support portion and forms an internal volume capable of receiving a guide bearing 80. The guide bearing 80 is arranged between the axial extension bearing surface 140 and the disc holder 40 d 'entrance. The guide bearing 80 is common to the first and second clutches E1 and E2. The guide bearing 80 is of the ball bearing type and guides the first and second clutches E1, E2 in rotation relative to the control system 90.

The guide bearing 80 is in axial support on the disc carrier 40 input. On its inner periphery, the input disc carrier 40 comprises a cylindrical bearing portion 46 of the plate 45, into which is inserted the outer race of the guide bearing 80. The integration of the guide bearing within the carrier -discs 40 input allows a recovery of axial forces without altering the axial size of the clutch system 1.

In FIGURE 1, the guide bearing 80 is an angular contact ball bearing.

The first member and the second force transmission member 60, 70 respectively comprise a first and a second elastic return elements 61, 62, in order to generate a sufficient force to restore the force transmission member and the corresponding clutch in their initial configurations called disengaged.

In the examples illustrated, the first elastic return element 61 of the first force transmission member 60 is formed by a first support plate 10 of radial elongation L1 and a plurality of first groups 11 of 100 helical springs. The second elastic return element 71 of the second force transmission member 70 is formed by a second support plate 20 of radial elongation L2 and at least one second group 21 of 200 helical springs.

In the first embodiment, the first elastic return element 60 is arranged radially beyond the second elastic return element 70. Therefore, the first support plate 10 surrounds the second support plate 20.

By way of example in FIGURES 2 to 5, the two support plates 10, 20 have an identical thickness Ep.

These elastic return elements 61, 62 together form an elastic return device 50 for the two force transmission members 60, 70, so as to reduce bulk. The elastic return device 50 also comprises a common support plate 30, here of annular shape with axis X and radial elongation L0, which supports all of the first and second (s) groups of helical springs 61, 71 , in order to avoid any interference between the support plates and the coil spring groups. In general, each of the radial elongations L1, L2, L0 is delimited between the radially inner and outer edges of the corresponding bearing plate 10, 20, 30. The radially internal periphery defines the internal diameter D0 of a corresponding bearing plate 10, 20, 30. The radially outer circumference defines the outer diameter of a corresponding support plate 10, 20, 30, as illustrated in FIGURES 2 to 5.

Preferably, the elastic return device 50 is supported on the input disc carrier 40 and in particular housed in a depression 47 of the plate 45, at the level of its common bearing plate 30. The depression 47 formed in the entry disc carrier 40 is arranged on a diameter located beyond the bearing surface of the cylindrical support portion 46.

In a variant not shown, the elastic return device 50 can rest on the clutch housing or on a central hub supporting said clutches.

In another variant not shown, means for anti-rotation of the elastic return device 30 relative to the input disc carrier 40 can also be formed on the outer periphery of the common support plate 30, for example a interlocking connection during assembly.

By forming different groups 11, 21 of springs intended to bring them closer together, the loss of angular space between these springs is limited, called the free space when they are arranged around the axis X. This free space is defined by example between the first groups 11 of springs 100 spaced from each other around the X axis, or even in special cases, between the second groups 21 of springs 200 spaced from each other around the X axis.

The greater the number of springs forming a group 12, 21 of springs, the greater the free space between the groups of springs, and the more the size of said device is reduced, and vice versa.

Also, the more the number of groups of springs is limited, the greater the free space between the groups of springs, the greater the free space between groups of springs, and vice versa.

The first groups 11 of springs are arranged around the axis X along a first implantation diameter D1. In the examples illustrated, each first group 11 of springs 100 is positioned between the common support plate 30 and the first support plate 10. The first groups 11 of coil springs 100 are distributed angularly around the axis X to come bearing on a first force transmission member 60. The first force transmission member 60 is for example interposed axially between the first clutch E1 and the first actuating piston 110.

The springs 200 of the second group(s) 21 are arranged along a second implantation diameter D2. Each second group 21 of springs 200 is positioned between the common support plate 30 and the second support plate 20. The second groups 21 of helical springs 200 are distributed angularly around the axis X to bear on a second member force transmission 70. The second force transmission member 70 is interposed axially between the second clutch E2 and the second actuating piston 210.

In order to reduce the axial size of the clutch system 1, the two clutches E1, E2, the elastic return device 60, 70 and the guide bearing 80 are concentric and are nested radially within the disc carrier 40 of entrance.

Preferably, the first and second support plates 10, 20 are arranged along the axis X on the same side of the common support plate 30. In the examples illustrated, the installation diameters D1, D2 of the springs 100, 200 are different but they remain substantially close to each other to reduce the radial size.

In other words, the second implantation diameter D2 of the springs 200 is formed partly on the first bearing plate 10. In a complementary manner, the first implantation diameter D1 of the springs 100 is formed partly on the second bearing plate 20, as illustrated for example in FIGURES 1 to 3.

In the examples illustrated, the elastic return device 50 comprises four first groups of springs arranged angularly around the axis X. Preferably, the springs 100 constituting a first group 11 of springs 100 are close to each other and have a identical shape and height. In FIGURES 2 to 5, the first groups 11 are identical, in other words, each first group 11 is formed with the same number of springs 100 and following a similar arrangement, here five springs 100 brought together to form a first group 11.

In particular in FIGURES 2 to 4, the elastic return device 50 comprises a plurality of second groups 21 of springs, ie a number comprised between four and eight groups 21 of springs.

In the first mode and the second embodiment, the elastic return device 50 comprises four second groups 21 of springs 200 arranged angularly around the axis X, with an identical number of springs 200, of the same height. The first and second groups of springs are angularly offset from each other, along the axis X. In FIGURES 1 to 5, the springs of the first and second groups 11, 21 are of identical shapes, that is to say of the same stiffness and height. As a variant not shown, the springs 100 and 200 can have different heights and stiffnesses.

In order to reduce the radial bulk, the first and second groups 11, 21 of springs are moved closer to each other, so as to be interleaved, for example. For example, at least one of the springs 200 from a second group 21 of springs is arranged between two first groups 11 of immediately adjacent springs.

In this way, the free space accommodates in an optimized manner at least in part the springs 200 of another group 21 arranged along a different implantation diameter.

By way of example in FIGURES 4 to 5, three springs of a second group 21 are arranged in the space between two groups 11 of immediately adjacent springs. In general, the springs 200 of the second group(s) 21 are distributed relative to the first groups 11 of springs 100, further reducing the radial bulk.

Advantageously, the springs of the first groups 11 and of the second groups 21 are distributed alternately around the axis X, for example alternately according to a staggered arrangement, as illustrated in FIGURES 2 to 4, this is ie alternately one by one, on two different implantation diameters D1, D2.

In the first and second embodiments, the radial elongation L1 of the first bearing plate 10 extends variably around the axis X, more precisely, continuously in a circumferential direction and radially between the diameters interior and exterior of the first bearing plate. Similarly, the radial elongation L2 extends variably around the axis X, more precisely, continuously in a circumferential direction and radially between the inner and outer diameters of the second bearing plate 20.

The radial elongation L1 extends according to the arrangement of the first groups 11 that the support plate 10 supports. The radial elongation L1 is maximum at the level of a first group 11 of springs which it supports, and it extends for example between 55% and 95% of the radial elongation L0 of the common bearing plate 30. The radial elongation L1 is minimal when it does not support any spring 100, in other words, at the level of the free space between the groups 11 of springs.

Similarly, the radial elongation L1 extends according to the arrangement of the second group(s) 21 that the bearing plate 20 supports. The radial elongation L2 is maximum at the level of a second group 21 of springs which it supports, and it extends for example between 55% and 95% of the radial elongation L0 of the common bearing plate 30. The radial elongation L2 is minimal when it does not support any spring 100, in other words, at the level of the free space between the groups 21 of springs

By way of example, the maximum dimensions of the radial elongations L1, L2 are identical and they correspond to approximately 75% of the radial elongation L0 in FIGURES 2 to 3. Similarly, the minimum dimensions of the radial elongations L1, L2 are identical and they correspond to approximately 13% of the radial elongation L0 in FIGURES 2 to 3.

In particular, the radial elongation L1 of the first bearing plate extends to a variable distance ΔD around the axis X. Furthermore, the radial elongation L2 of the second bearing plate extends to a fixed distance around the X axis.

In particular, the second group or groups 21 of springs are nested in the first support plate 10 through cutouts 15 of the first support plate 10, called “first cutouts 15”. In the examples illustrated, the springs 200 of the second group(s) 21 pass through the first support plate 10. Each first cutout 15 passes through at least two springs 200. Preferably, each first cutout 15 passes through a whole second group 21 of springs.

In the first and second embodiments, the springs 100 of the first groups 11 pass through the second support plate 10. The first groups 11 of springs are nested in the second support plate 20 through cutouts 25 of the second plate support 20, called "second cutouts 25". Each second cutout 25 lets through at least two springs 100. Preferably, each second cutout 25 lets through a whole first group 11 of springs.

In FIGURES 1 to 3, the first cutouts 15 each comprise an open shape, that is to say delimited by an open-type contour.

In FIGURES 1 to 3, the second cutouts 25 each comprise an open shape, that is to say delimited by an open-type contour.

Consequently, in the first and second embodiments, the first bearing plate 10 has a shape complementary to that of the second bearing plate 20. The two bearing plates 10, 20 are therefore close together and nested one in the other. By “nesting”, we mean that the first support plate 10 can slide axially through the second support plate 20, and vice versa, without interfering with each other. The advantage here is to optimize the size of the two support plates, by interlocking shapes using a reduced quantity of material.

More precisely, the cutouts 25 of the second support plate 20 partly receive the first support plate 10. The second cutouts 25 are formed on the radially outer periphery of the second support plate 20. In a similar manner , the cutouts 15 of the first support plate 10 partly receive the second support plate 20. The first cutouts 15 are formed on the radially inner periphery of the first support plate 10.

In particular within the same support plate 10 or 20, the cutouts 15 or 25 are spaced from each other.

In FIGURES 2 to 3, each support plate 10, 20 comprises four cutouts 15 and four cutouts 25 distributed angularly around the axis X, in a regular manner. Preferably, the first cutouts 15 of the first support plate 10 are angularly offset from the second cutouts 25 of the second support plate 20, preferably alternately, here one by one.

The remaining parts advantageously delimited between the cutouts 15, 25 of the same support plate form support portions 16, 26.

In this way, the support portions 16 of the first support plate 10 cooperate with the first force transmission member 60, in order to return it elastically to its initial position called disengaged.

Similarly, the support portions 26 of the second support plate 20 cooperate with the second force transmission member 70, in order to return it elastically to its initial position called disengaged.

Two immediately adjacent cutouts 15 delimit between them a support portion 16. Each support portion 16 of the first support plate supports at least two springs 100, more precisely a first group 11 of springs.

Similarly, two immediately adjacent cutouts 25 delimit between them a support portion 26. Each support portion 16 of the second support plate supports at least two springs 200, more precisely a second group 21 of springs.

In FIGURES 2 to 3, each of the four bearing portions 16 support a first group 11. The bearing portions 16 extend radially inward from the first bearing plate 10. The bearing portions 16 are identical and angularly regularly spaced around the X axis.

In FIGURES 2 to 3, each of the four bearing portions 26 support a second group 21. The bearing portions 26 extend radially outward from the second bearing plate 20. The bearing portions 26 are identical and angularly regularly spaced around the X axis.

Advantageously, a support portion 16 of the first support plate 10 is of complementary shape to that of a cutout 25 of the second support plate 20, with which it fits, and vice versa. In FIGURES 2 to 3, the second cutouts 25 are thus intended to receive the support portions 16 of the first support plate 10.

During actuation and elastic return of the first force transmission member 60, each support portion 16 can then advantageously slide axially through one of the cutouts 25, without interfering with each other.

Similarly, a support portion 26 of the second support plate 20 has a shape complementary to that of a cutout 15 of the first support plate 10, with which it fits, and vice versa. In FIGURES 2 to 3, the first cutouts 15 are thus intended to receive the support portions 26 of the second support plate 20.

During actuation and elastic return of the second force transmission member 70, each support portion 26 can then advantageously slide axially through one of the cutouts 15, without interfering with each other.

Preferably, each support portion 16, 26 is a solid male-shaped portion. Each cutout 15, 25 is a female shaped opening. A support portion 16, 26 is for example, in a plane orthogonal to the axis X, a projection, of rounded convex type or tooth-shaped. A support portion can be of polygonal shape, for example, of the triangular, rectangular, or trapezoidal type. A cutout 15, 25 can be, for example, in a plane orthogonal to the axis X, a cavity or a recess of circular or rounded shape.

Advantageously, each cutout 15, 25 is formed with a certain minimum play J between the two support plates in order to avoid any risk of snagging between the support plates or the groups of springs.

So as to reduce the axial compactness, the first force transmission member 60 passes through orifices 76 provided in the second force transmission member 70 to press on the first support plate 10. The first force transmission member force 65 includes bearing tabs 66 formed on its inner periphery. The support tabs 66 are distributed angularly around the axis X and thus pass through through the holes 76 of the second force transmission member. In particular in FIGURE 1, the support tabs 66 form an insert on a cylindrical support portion 65 of the first force transmission member 60.

A lubrication ring 55 is also disposed radially between the axial extension bearing 140 and the disc carrier 40 input. Lubrication ring 55 bears axially on guide bearing 80. Lubrication ring 55 is retained axially by a split ring fitted into a groove provided on axial extension surface 140 of housing 130.

Advantageously, the lubricating ring 55 comprises lubricating pipes 51 passing radially right through the ring and opening onto the outer periphery. The lubrication lines 51 are oriented radially in the direction of the clutches E1 and E2. The housing 130 of the control system 90 also includes cooling fluid supply lines 131 which communicate directly with the lubrication lines 51. The lubrication ring 55 thus channels the cooling fluid coming from the actuation system in the direction of the first and second clutches E1, E2 and promotes their lubrication.

Advantageously, bosses 35, 36 are formed on the common support plate 30, on which are arranged springs 100, 200 respectively of a first group 11 and/or of a second group 21. Preferably, these bosses 35, 36 are by stamping and/or drilling the common support plate 30.

Certain bosses 36 form guide studs, adapted to receive a single spring 100 or 200.

Other bosses 35, in the form of borders or cords, each receive a plurality of springs 100 or 200, preferably a first group 11 or a second group 21 of springs.

Therefore, the springs 100, 200 resting on said bosses 35, 36 are raised and arranged so as to be axially closer to their corresponding transmission member 60, 70. In FIGURES 1 to 2, the second support plate 20 is arranged axially beyond the first support plate 10. In a variant not shown, the common support plate 30 may comprise at least one ring-shaped boss , i.e. extending continuously around the X axis.

There is shown in FIGURE 3, a second embodiment of a clutch system 1 similar to the first embodiment, except that the first and second bearing plates 10, 20 are of coplanar type. In other words, the two support plates 10, 20 are spaced from the common support plate 30 along the same axial distance.

In this second mode, the two support plates 10, 20 face each other, in particular thanks to identical heights of springs 100, 200. In a variant not shown, the two support plates 10, 20 can be positioned coplanar, with springs 100 and 200 of different shapes. In such a situation, the difference in heights between the springs 100, 200 would be filled by bosses 35, 36, for example of different dimensions, formed on the common support plate 30. By way of example, the gap between the springs 100 and 200 along the X axis, could define the height or axial dimension of said bosses supporting the smaller springs 100 or 200.

There is shown in FIGURE 4, a third embodiment of a clutch system 1 substantially similar to the first embodiment, except that the first bearing plate 10 is disposed axially between the common bearing plate 30 and the second bearing plate 20.

Therefore, only the springs 200 of the second group or groups 21 are nested in the support plate 10, thanks to the cutouts 15 of the first support plate receiving said springs 200. In FIGURE 4, the cutouts 15 are arranged substantially in the center of the first support plate 10. Each cutout 15 is of closed shape, delimited by a closed contour, preferably of circular or oval shape. In particular, each cutout 15 receives a single spring 200.

In a variant not shown, a cutout 15 can receive a plurality of springs 200, to reduce the number of cutouts during the manufacturing process.

In particular in this third mode, the cutouts 15 are grouped together, so as to follow the distribution of the second groups 21 of springs 200. Certain cutouts 15 are for example arranged as close as possible to the first groups 21 of springs 200. Similarly, the implantation diameters D1, D2 of the springs 100, 200 are substantially close to each other to reduce the radial size. Other cutouts 15 are arranged between the first groups 11, at the level of the free spaces provided between said groups 11 of springs 100.

Such a configuration thus makes it possible to further reduce the radial bulk, and in particular to reduce the radial elongation L1, L2, L0 of the support plates 10, 20, 30 of the elastic return device 50.

Similarly, bosses 35, 36 of the common support plate 30 are arranged opposite the cutouts 15, so as to receive the springs 200, in particular to arrange the two support plates 10, 20 in a coplanar manner.

Similarly, the radial elongation L0 of the common bearing plate and the radial elongation L1 of the first bearing plate are of identical dimensions in FIGURE 4. Note that the radial elongation L2 of the second plate d support 20 is reduced compared to that of the first plate 10, by way of example, half the radial elongation L1 of the first support plate 10. The radial elongation L2 of the second support plate 20 is here sized according to the diameter of the springs 200.

There is shown in FIGURE 5 a fourth embodiment of a clutch system 1 substantially similar to the first embodiment except that the elastic return device 50 comprises a single second group 21 of springs 200. Therefore, the springs 200 are angularly distributed regularly around the axis X.

Such a configuration makes it possible to further reduce the radial bulk, and in particular to reduce the radial elongation L1, L2, L0 of the support plates 10, 20, 30 of the elastic return device 50. For example, certain springs 200 are arranged as close as possible to the first groups 11 of springs 100. Therefore, the installation diameters D1, D2 of the springs 100, 200 are different and substantially close to each other, to reduce the radial size. Other springs 200 are on the contrary arranged between the first groups 11 of springs, at the level of the free spaces provided between said groups 10.

In particular in FIGURE 5, the cutouts 15 of the first support plate 10 are regularly distributed angularly around the axis X. Bosses 35, 36 of the common support plate 30 are also arranged opposite the cutouts 15 , so as to receive the springs 200. Similarly, the radial elongations L0 and L1 are of identical dimensions.

Analogously to the third mode, the first support plate 10 is arranged axially between the common support plate 30 and the second support plate 20. Therefore, only the springs 200 of the second group or groups 21 are nested in the support plate 10, via the cutouts 15. Similarly, the cutouts 15 are arranged substantially in the center of the first support plate 10. Each cutout 15 is of closed shape, delimited by a closed contour, of preferably circular or oval in shape. In particular, each cutout 15 receives a single spring 200. In a variant that is not shown, a cutout 15 can receive a plurality of springs 200, to reduce the number of cutouts during the manufacturing process.

Of course, the present invention is not limited to the embodiments described and represented, provided by way of illustrative and non-limiting example.

Claims (10)

Elastic return device (50) for a clutch system, of axis X of revolution, comprising:
– a common support plate (30),
– a first support plate (10) and at least two first groups (11) of springs (100) positioned between the common support plate (30) and the first support plate (10),
– a second support plate (20), and at least a second group (21) of springs (200) positioned between the common support plate (30) and the second support plate (20). Elastic return device (50) according to claim 1, comprising a number of first groups (11) of springs (100) comprised between two and fifteen first groups (11) of springs (100) distributed around the axis X of revolution , wherein at least one of the springs (200) of said at least a second group (21) of springs is arranged between two first groups (11) of immediately adjacent springs (100). Elastic return device (50) according to Claim 1 or 2, in which a radial elongation (L1) of the first bearing plate (10) extends at a variable distance (ΔD) around the axis (X) , in particular said radial elongation (L1) of the first bearing plate (10) extends between 55% and 100% of a radial elongation (L0) of the common bearing plate (30). Elastic return device (50) according to any one of the preceding claims, in which the first groups (11) of springs (100) are nested in the second bearing plate (10). Elastic return device (50) according to any one of the preceding claims, in which the at least one second group (21) of springs (200) is embedded in the first bearing plate (10). A spring return device (50) according to any preceding claim, wherein the first backing plate (10) is complementary in shape to the second backing plate (20). Elastic return device (50) according to any one of the preceding claims, in which cutouts (15) are formed in the first bearing plate (10), the springs (200) of the at least one second group ( 21) passing through said cutouts (15), in particular said cutouts (15) are of open or closed shapes. Elastic return device (50) according to the preceding claim, in which bearing portions (26) of the second bearing plate (20) support the springs (200) of said at least one second group (21), said portions support (26) of the second support plate (20) being of complementary shape to that of the cutouts (15) of the first support plate (10). Elastic return device (50) according to any one of the preceding claims, in which the common bearing plate (30) comprises bosses (35, 36) adapted to receive at least one spring (100, 200) of a first group (11) and/or a second group (21) of springs. Clutch system (1) intended to be integrated into a transmission chain, comprising:
– at least a first clutch (E1) and a second clutch (E2) respectively of the multi-disc type, controlled to selectively couple a driving shaft to a first driven shaft (A1) and to a second driven shaft (A2),
– a torque input disc carrier (40) supporting the first and second clutches (E1, E2),
– at least a first member and a second force transmission member (60, 70) arranged to respectively control the first clutch (E1) and second clutch (E2),
characterized in that it comprises an elastic return device (50) common to the first and second force transmission members (60, 70) according to any one of the preceding claims, said elastic return device (50) being in abutment on the input disc carrier (40).