FR3081947A1 - REACTION ELEMENT FOR A MULTI-DISC CLUTCH - Google Patents

Abstract

The invention relates to a reaction element (16) for a multi-plate clutch comprising a multi-disc assembly, in which the reaction element (16) has an axis of rotation X and comprises: - an annular portion (17) for orientation radial; - A support area (18), the support area (18) being configured to serve as a support point for the multi-disc assembly of the multi-disc clutch; in which the bearing zone (18) is formed of a plurality of projecting portions each extending over an angular sector, the projecting portions being separated from each other by intermediate zones each forming, between two consecutive projecting portions, a path allowing an oil passage.

Description

The invention relates to the field of motor vehicle clutches, in particular wet clutches.

The invention relates more particularly to a reaction element of such a clutch.

Technological background

Document EP2909052 discloses a double clutch for a double clutch transmission comprising a driving shaft, a first friction clutch, a second friction clutch, a first driven shaft, and a second driven shaft. Each of the clutches of the double clutch is a so-called wet multi-disc clutch, which means that the clutch discs are immersed in oil.

Each multi-plate clutch has an input disc carrier integral in rotation with an input element, for example the engine crankshaft, an output disc carrier integral in rotation with an output element, for example for the first clutch the first driven shaft, and a multidisk assembly comprising a plurality of friction discs integral in rotation about the axis X of one of the input and output disc carriers, and a plurality of plates respectively arranged on the side and on the other side of each friction disc, integral in rotation about the X axis of the other of the inlet and outlet disc holders. Friction pads are arranged between the plates. The friction discs and the plates are axially movable so that they can move towards each other.

Each clutch also has an actuating member which includes a force transmitting member. The force transmission member is axially movable to transmit a clutch force on the multidisk assembly from a disengaged position to a engaged position. Each clutch further comprises a reaction element integral in rotation and in translation with the output disc holder. The reaction element is placed opposite the force transmission member with respect to the multidisk assembly so that when the force transmission member exerts an axial force on the multidisk assembly thus displacing the friction discs and the plates, these come up against the reaction element which in turn exerts a reaction force opposite to the axial force of the force transmitting member. Thus the plates are clamped against the friction discs and the friction linings so that there is a torque transmission between the input element and the output element thanks to the axial force of the force transmission member and the reaction force of the reaction element in the engaged position.

The reaction element is formed of an annular portion of radial orientation in which a bearing region is formed on one face of the annular portion and projecting from said face of the annular portion. In the engaged position, the support zone makes it possible to serve as a support point for the multidisk assembly of the multidisc clutch, in particular the plate closest to the reaction element, it is therefore the support zone which exerts the reaction effort on the multidisc assembly.

It is known to the applicant that the support zone of these reaction elements of the prior art is formed all around the axis X on the face of the reaction element so as to form a continuous support zone transmitting thus the reaction force to the multidisc assembly all around the X axis. In order to allow an oil circulation between the reaction element and the plate adjacent to the reaction element, the reaction element is struck at the location of the support area so as to form struck areas at a plurality of points all around the X axis where the projection of the support area is attenuated which allows the oil to evacuate through these struck areas.

However, striking the reaction element generates beads on the ends of the struck areas which adversely affects the planar support of the reaction element and therefore the effectiveness of the reaction element in generating a force of homogeneous reaction on the multidisk assembly all around the X axis.

summary

A basic idea of the invention is to improve the reaction element so that the oil is evacuated efficiently while avoiding damaging the plane support of the reaction element in such a way to guarantee a uniform reaction effort on the multi-disc assembly.

According to one embodiment, the invention provides a reaction element intended for a multidisk clutch comprising a multidisk assembly, in which the reaction element has an axis of rotation X and comprises:

- an annular portion of radial orientation;

- a support area, the support area being configured to serve as a support point for the multi-disc assembly of the multi-disc clutch;

wherein the bearing zone is formed of a plurality of projecting portions projecting from said annular portion and each extending over an angular sector, the projecting portions being separated from each other by intermediate zones each forming between two consecutive projecting portions, a path allowing an oil passage.

Thanks to these characteristics, the reaction element allows, thanks to its discontinuous support zone, to efficiently evacuate the oil located between the reaction element and an adjacent plate of the multi-disc clutch. In addition, the intermediate zone located between the projecting portions of the support zone makes it possible to maintain the plane support of the reaction element so as to guarantee a homogeneous reaction force all around the X axis on a multidisc assembly. of the clutch.

According to other advantageous embodiments, such a reaction element can have one or more of the following characteristics.

According to one embodiment, the intermediate zones are non-deformed zones.

According to one embodiment, the reaction element is formed in one piece with one of the input and output disc holders.

According to one embodiment, the intermediate zones extend in the plane of the annular portion.

According to one embodiment, the projecting portions are arcuate portions.

According to one embodiment, the intermediate zones each extend over an angular range between 2 and 15 °.

According to one embodiment, the projecting portions are formed by stamping or calibration of the annular portion.

According to one embodiment, the projecting portions have a crown which is hardened, the hardened crown having a thickness less than a thickness of a part of the annular portion radially on either side of said crown.

Thanks to these characteristics, the hardened zone makes it possible to increase the stiffness of the support zone so as to more precisely ensure the support function of the reaction element and to improve the flatness of the support zone. The thickness here represents the dimension in section in the direction along the X axis.

In a plane passing through the X axis and cutting the support portion, the support portion has a V-shaped section.

According to one embodiment, the invention provides a multi-plate clutch, in particular for a motor vehicle, comprising:

- an input disc holder,

- an output disc holder,

- A multi-disc assembly comprising at least one friction disc integral in rotation about the axis X of one of the input and output disc carriers, at least two plates respectively arranged on either side of the at least one friction disc, the two plates being integral in rotation about the axis X of the other of the inlet and outlet disc holders; and

- a reaction element as described above, the reaction element being integral, axially and in rotation about the X axis, with one of the input and output disc carriers, and being configured to exert on the multidisk assembly a reaction force when a clutch force is exerted on said multidisk assembly.

According to one embodiment, the reaction element is formed in one piece with one of the input and output disc holders.

According to one embodiment, the multi-plate clutch further comprises an actuating member comprising a force transmission member, the force transmission member being axially movable from a disengaged position to a clutched position for applying a force of clutch on the multi-disc assembly.

According to one embodiment, the force transmission member is arranged so as to sandwich the multidisc assembly with the reaction element and in which in the engaged position, said plates and at least one friction disc are pinched by the force transmission member and the reaction element with the clutch force and the reaction force so as to transmit a torque between the input disc holder and the output disc holder.

According to one embodiment, the reaction element is a support disc fixed to one of the entry and exit disc holders.

According to one embodiment, the reaction element is integral with the outlet disc holder.

According to one embodiment, one or each disc holder comprises a cylindrical skirt configured to cooperate with the plates and the friction discs of the multidisk assembly.

According to one embodiment, the cylindrical skirt comprises grooves cooperating with the grooves of the plates and friction discs of the multidisk assembly.

According to one embodiment, the invention provides a torque transmission device, in particular for a motor vehicle, comprising:

- a torque input element in rotation about an axis, capable of being coupled in rotation to a crankshaft of a heat engine,

- a first torque output element, capable of being coupled in rotation to a first input shaft of a gearbox,

- an intermediate element arranged between the torque input element and the torque output element, in the sense of the torque transmission,

a first clutch as described above, the first clutch being an input clutch, selectively and frictionally coupling the torque input element and the intermediate element,

- at least a second clutch as described above, the second clutch being a first output clutch, selectively and frictionally coupling the intermediate element and the first torque output element.

According to one embodiment, the torque transmission device comprises:

- a second torque output element, capable of being coupled in rotation to a second input shaft of a gearbox,

- a third clutch as described above, the third clutch being a second output clutch, selectively and frictionally coupling the intermediate element and the second torque output element.

According to one embodiment, the invention provides a method of manufacturing a reaction element intended for a multi-plate clutch comprising a multi-plate assembly in which the method comprises the following steps:

- provide a part comprising an annular portion;

- Form a support area on one side of the annular portion using a shaping tool so that the support area protrudes from said face of the annular portion, the support area being configured to act as a fulcrum for the multi-plate assembly of the multi-plate clutch, the shaping tool comprising a plurality of punches each extending over an angular sector, the punches being spaced from each other so that that the support zone is formed in a plurality of projecting portions each extending over an angular sector, the projecting portions being separated from each other by intermediate zones each forming, between two consecutive projecting portions, a path allowing passage oil

According to one embodiment, the shaping tool comprises as many punches as projecting portions to be produced.

According to one embodiment, the step of forming the support zone is carried out by stamping or calibration.

According to one embodiment, during the step of forming the support zone by calibration, a vertex of the protruding portions is hardened, the hardened vertex having a thickness less than a thickness of a part of the annular portion radially on either side of said vertex.

Brief description of the figures

The invention will be better understood, and other objects, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely by way of illustration and without limitation. , with reference to the accompanying drawings.

- Figure 1 shows a partial sectional view of a triple wet clutch for hybrid architecture according to a first embodiment of the invention.

- Figure 2 shows a rear perspective view of a disc holder provided with a reaction element according to an embodiment of the invention.

- Figure 3 shows a front perspective view of the disc holder of Figure 2.

- Figure 4 shows a partial perspective view of the disc carrier of Figures 2 and 3.

Detailed description of embodiments

In the description and the claims, the terms external and internal as well as the axial and radial orientations will be used to designate, according to the definitions given in the description, elements of the torque transmission device. By convention, the radial orientation is directed orthogonally to the axis X of rotation of the different clutches determining the axial orientation and, from the inside to the outside while moving away from said axis X, the circumferential orientation is directed orthogonally to the X axis and orthogonally to the radial direction. The terms external and internal are used to define the relative position of one element with respect to another, with reference to the X axis, an element close to the axis is thus qualified as internal as opposed to an external element located radially on the periphery. Furthermore, the terms rear AR and front AV are used to define the relative position of one element with respect to another in the axial direction, an element intended to be placed close to the heat engine being designated by front and an element intended to be placed close to the gearbox being designated by rear.

FIG. 1 represents a torque transmission device 1 comprising:

- a torque input element 2 capable of being coupled in rotation to a crankshaft of a heat engine (not shown),

- a first torque output element 3, capable of being coupled in rotation to a first input shaft of a gearbox (not shown),

- a second torque output element 4, capable of being coupled in rotation to a second input shaft of a gearbox (not shown) and

- an intermediate element 5 arranged between the torque input element 2 and the first 3 and second 4 torque output element, according to the torque transmission path.

In the embodiment shown in Figure 1, the first and second outlet elements 3, 4 comprise a web and a hub whose internal periphery is grooved and able to cooperate, respectively with a first and a second gearbox shaft. In the example considered, the first and second box shafts are coaxial.

The device 1 also includes an input clutch 10 which selectively and frictionally couples the input element 2 and the intermediate element 5.

The input clutch 10 includes:

- an input disc holder 11 integral in rotation with the input element 2,

- an output disc holder 12 integral in rotation with the intermediate element 5, and

- A multi-disc assembly 13 comprising several friction discs, here four, integral in rotation with the input disc holder 11, several plates respectively arranged on either side of each friction disc, integral in rotation with the disc holder outlet 12. The friction discs have friction linings attached to each side of their support disc. In a clutched position of the clutch 10, the plates pinch the friction linings so as to transmit a torque between the input disc holder 11 and the output disc holder 12.

Each disc holder 11, 12 synchronizes in rotation the set of plates and the set of friction discs. Each disc holder 11, 12 comprises a cylindrical skirt on which the plates or the friction discs are mounted.

The friction discs of the multidisk assembly 13 have grooves on their radially inner periphery which cooperate with grooves located on the radially outer periphery of the cylindrical skirt of the input disc holder 11. The friction discs are therefore radially the outside of the cylindrical skirt.

The plates of the multidisc assembly 13 have grooves on their radially outer periphery which cooperate with grooves located on the radially inner periphery of the cylindrical skirt of the output disc holder 12.

The input clutch also comprises a reaction element 16 having an annular portion 17 of radial orientation and a support area 18 projecting from one face of the annular portion 17. The support area 18 of the The purpose of the reaction element 16 is to serve as a support for the multidisc assembly and in particular for the plate adjacent to the reaction element 16 in the engaged position. The reaction element 16 is fixed in rotation about the axis X and axially along the axis X to the output disc holder 12.

In the embodiment shown in FIGS. 1 to 4, the reaction element 16 and the output disc holder 12 form one and the same element of the input clutch 10. In fact, the reaction element 16 is here formed on one of the ends of the outlet disc holder so as to be placed parallel to the plates and to the friction discs of the multidisc assembly 13.

The support zone 18 is formed of a plurality of projecting portions each extending over an angular sector, the projecting portions being arcuate and separated from each other by an intermediate zone. In another embodiment not shown, the projecting portions are linear.

The device also comprises a first output clutch 20 selectively and frictionally coupling the intermediate element 5 and the first output element 3 and a second output clutch 30, selectively and frictionally coupling the intermediate element 5 and the second element exit 4.

The first output clutch 20 includes:

- an input disc holder 21 integral in rotation with the intermediate element 5,

an output disc holder 22 integral in rotation with the first output element and,

- A multi-disc assembly 23 comprising several friction discs, here three, integral in rotation with the outlet disc holder 22, several plates respectively arranged on either side of each friction disc, integral in rotation with the disc holder entry 21. The friction discs have friction linings attached to each side of their support disc. In a clutched position of the clutch 20, the plates pinch the friction linings so as to transmit a torque between the input disc holder 21 and the output disc holder 22.

Each disc holder 21, 22 comprises a cylindrical skirt on which the plates or the friction discs are mounted.

The friction discs of the multidisk assembly 23 have grooves on their radially inner periphery which cooperate with grooves located on the radially outer periphery of the cylindrical skirt of the output disc holder 22.

The plates of the multidisc assembly 23 have grooves on their radially outer periphery which cooperate with grooves located on the radially inner periphery of the cylindrical skirt of the input disc holder 21.

The first output clutch 20 also comprises a reaction element 26 having an annular portion 27 of radial orientation and a bearing zone 28 located on one face of the annular portion 27 and projecting from said face of the annular portion 27. The support zone 28 of the reaction element 26 is intended to serve as a support point for the multi-disc assembly and in particular the plate adjacent to the reaction element 26 in the engaged position. The reaction element 26 is fixed in rotation about the X axis and axially along the X axis to the input disc holder 21.

In the embodiment shown in FIG. 1, the reaction element 26 and the input disc holder 21 are formed on two separate parts of the clutch 20.

The support area 28 is likely to have a structure similar to the support area 16 described above.

The second output clutch 30 is formed analogously to the first output clutch 20. The second output clutch 30 therefore similarly comprises an input disk carrier 31, an output disk carrier 32, a multi-disc assembly 33, a reaction element 36 provided with an annular portion 37 and a support zone 38.

In the embodiment shown in FIG. 1, the reaction element 36 and the input disc holder 31 are two separate elements from the second output clutch 30, fixed to each other. Indeed, the reaction element 36 is here a support disc fixed on one of the ends of the input disc holder 31 so as to be placed parallel to the plates and to the friction discs of the multidisc assembly 33. In one mode embodiment not shown, the reaction element 36 and the output disc holder are one and the same element.

Each disc holder 11, 12, 21, 22, 31, 32 can synchronize in rotation all of the plates or all of the friction discs associated therewith.

According to different embodiments, the plates are rotationally integral with the input disc carriers 11,21,31 and the friction discs are rotationally integral with the output disk carriers 12, 22, 32. As a variant, the plates are integral in rotation with the output disc holder 12, 22, 32 and the discs are integral in rotation with the input disc holder 11, 21, 31.

The clutches are of the wet type and comprise for example between two and seven friction discs, preferably three or four friction discs. Such multi-disc clutches make it possible to limit the radial height of the torque transmission device.

The first output clutch 20, the second output clutch 30 and the input clutch 10 are arranged radially one inside the other. In other words, there is a plane perpendicular to the axis of rotation which intersects both the output clutches 20, 30 and the input clutch 10.

Here, the input clutch 10 is arranged radially inside the second output clutch 30 which is arranged radially inside the first output clutch 20.

The device 1 comprises an actuating member 14 and a force transmitting member 15 associated with the input clutch 10. A holding member in the disengaged position can be provided to push the force transmitting member 15 from the input clutch 10.

The force transmitting member 15 is axially movable to transmit the clutch force from the actuating member 14 to the input clutch 10. The force transmitting member exerts an axial force on the multidisk assembly 13 for moving the platters towards the discs. The actuation is thus of the "pushed" type.

The force transmission member 15 has a curved outer radial end defining a support surface for exerting the axial force on the multidisc assembly, continuous or discontinuous.

The force transmission member 15 is placed at the front of the multi-disc assembly 13 while the reaction element 16 is placed at the rear of the multi-disc assembly 13.

Thus, in the engaged position of the input clutch 10, the force transmission member 15 is moved axially from front to rear so as to transmit a clutch force on the multidisk assembly 13 tending bringing the plates and friction discs closer to the reaction element 16. When the plate adjacent to the reaction element 16 comes into contact with the support zone 18, the reaction element 16 then exerts a reaction force on the multidisk assembly 13 opposite the clutch force, ie from the rear to the front. In this way, the plates and the friction discs of the multidisk assembly 13 are pinched between the reaction element 16 and the force transmission member 15 by means of the reaction force and the force. clutch which allows to transmit the torque between the plates and the friction discs and therefore between the input element 2 and the intermediate element 5.

The device 1 also comprises an actuating member 24 and a force transmitting member 25 associated with the first output clutch 20. The force transmitting member 25 is axially movable to transmit the clutch force from the member actuation 24 towards the friction discs and plates of the first output clutch 20.

The device 1 also comprises an actuating member 34 and a force transmitting member 35 associated with the second output clutch 30. The force transmitting member 35 is axially movable to transmit the clutch force from the member actuation 34 to the friction discs and plates of the second output clutch 30.

The force transmission members 25, 35 are placed at the rear of the multi-disc assemblies 23, 33 while the reaction elements 26, 36 are placed at the front of the multi-disc assemblies 23, 33.

In the engaged position of the output clutches 20, 30, the force transmission members 25, 35 and the reaction elements 26, 36 act similarly to those of the input clutch 10.

Holders in the disengaged position may be provided to push the force transmission members 25, 35 from the output clutches 20, 30.

The actuators 24, 34 of the output clutches 20, 30, in particular their actuation chamber are arranged radially one inside the other. The actuators 24, 34 of the output clutches 20, 30 are on one side, axially speaking, first and second output elements 3, 4 and the actuator 14 of the input clutch 10 is on the other side of the first and second output elements 3, 4.

The force transmission members 25, 35 of the output clutches 20, 30 each have a curved outer radial end defining a bearing surface for exerting the axial force on the multi-disc assemblies, 23, 33.

The intermediate element 5 is coupled to a connection piece 6 capable of being driven in rotation by a rotary electric machine via a pinion C around an axis parallel to the axis X. The connection piece 6 is here axially offset from the clutches 10, 20, 30. The connection piece 6 is capable of being driven directly by the pinion.

Figures 2 to 4 illustrate separately the output disc holder 12 and the reaction element 16 of the input clutch 10 in one embodiment.

The output disc holder 12 has a fluted peripheral skirt allowing the friction discs of the multidisc assembly to be coupled in rotation

13. In this embodiment as illustrated, the reaction element 16 and the outlet disc holder 12 are one and the same part where the reaction element 16 extends radially inwards from the end. rear of the peripheral skirt of the output disc holder 12. Thus, the reaction element 16 is parallel to the multidisk assembly 13 and is adjacent to one of the plates of the multidisk assembly 13.

The reaction element 16 is formed of an annular portion 17 of radial orientation where a bearing area 18 is formed on the front face of the annular portion 17 and projecting from said front face of the annular portion 17. The support zone 18 is formed discontinuously on the front face of the annular portion 17 of a plurality of projecting portions each extending over a different angular sector, the projecting portions being arched and separated from each other by a zone intermediate.

Thus, the support zone 18 is substantially discontinuous all around the axis X. In addition, the intermediate zone separating the various arcuate portions is planar or substantially planar thus allowing the oil to be evacuated through the space located between the plate adjacent to the reaction element 16 and the intermediate zone. Indeed, the intermediate zone is a zone which has not been deformed by the step of forming the support zone 18, it is therefore in the continuity of the annular portion 17. In order to optimize the evacuation oil, it may be preferable that each intermediate zone is sufficiently large to be sufficient for the evacuation of the oil flow. For example, the intermediate zones can each extend over an angular range of between 2 and 15 °.

The bearing zone 18 is formed by a calibration of the annular portion 17 of the reaction element 16. As visible in particular in FIG. 4, the calibration makes it possible to obtain a work hardening on a vertex 19 of the projection formed by the support zone 18. The hardened apex has a thickness that is less than a thickness of a part of the annular portion radially on either side of said apex. In section, the support zone thus has a V shape.

The hardened top 19 is obtained using a shape which is not complementary to the punch or upper die with the lower die. Indeed, so that the apex 19 is work hardened, the punch or the lower die must have at the apex to form a shape slightly greater than the necessary complementary shape so as to limit at this level the thickness of the reaction element 16, 26, 36.

This support zone structure 18, 28, 38 may be present in one or more of the clutches 10, 20, 30.

Although the invention has been described in connection with several particular embodiments, it is obvious that it is in no way limited thereto and that it includes all the technical equivalents of the means described as well as their combinations if these are within the scope of the invention.

The use of the verb "behave", "understand" or "include" and its conjugate forms do not exclude the presence of other elements or steps than those set out in a claim.

In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

Claims (13)

1. Reaction element (16, 36, 36) for a multi-plate clutch (10, 20, 30) comprising a multidisc assembly (13, 23, 33), in which the reaction element (16, 36, 36) has an axis of rotation X and includes: - an annular portion (17, 27, 37) of radial orientation; - a support area (18, 28, 38), the support area (18, 28, 38) being configured to serve as a support point for the multidisc assembly (13, 23, 33) of the multi-plate clutch (10, 20, 30); wherein the support zone (18, 28, 38) is formed of a plurality of projecting portions projecting from said annular portion (17, 27, 37) and each extending over an angular sector, the projecting portions being separated from each other by intermediate zones each forming, between two consecutive projecting portions, a path allowing an oil passage. 2. Reaction element (16, 36, 36) according to claim 1, in which the intermediate zones are planar. 3. Reaction element (16, 36, 36) according to claim 2, in which the intermediate zones extend in the plane of the annular portion (17, 27, 37). 4. Reaction element (16, 36, 36) according to one of claims 1 to 3, wherein the projecting portions are arcuate portions. 5. Reaction element (16, 36, 36) according to any one of the preceding claims, in which the intermediate zones each extend over an angular range between 2 and 15 °. 6. Reaction element (16, 36, 36) according to any one of the preceding claims, in which the projecting portions are formed by stamping or calibration of the annular portion (17, 27, 37). 7. Reaction element (16, 36, 36) according to any one of the preceding claims, in which the projecting portions have an apex (19) which is hardened, the hardened apex (19) having a thickness thinner than a thickness of part of the annular portion (17, 27, 37) radially on either side of said apex (19). 8. Multidisk clutch (10, 20, 30), in particular for a motor vehicle, comprising: - an input disc holder (11,21, 31), - an output disc holder (12, 22, 32), - a multi-disc assembly (13, 23, 33) comprising at least one friction disc integral in rotation about the axis X of one of the inlet (11, 21, 31) and outlet (12) disc holders , 22, 32), at least two plates respectively disposed on either side of the at least one friction disc, the two plates being integral in rotation about the axis X of the other of the disc carriers d 'inlet (11, 21, 31) and outlet (12, 22, 32); and - a reaction element (16, 36, 36) according to any one of claims 1 to 7, the reaction element (16, 36, 36) being integral, axially and in rotation about the X axis, one of the input (11, 21, 31) and output (12, 22, 32) disc carriers, and being configured to exert on the multidisc assembly (13, 23, 33) a reaction force when 'a clutch force is exerted on said multidisk assembly (13, 23, 33). 9. The clutch as claimed in claim 8, in which the reaction element (16, 36, 36) is formed integrally with one of the input (11, 21, 31) and output (12) disc carriers. , 22, 32). 10. A clutch according to claim 8 or claim 9, in which the reaction element (16, 36, 36) is integral with the output disc holder (12, 22, 32). 11. A method of manufacturing a reaction element (16, 36, 36) for a multi-plate clutch (10, 20, 30) comprising a multi-plate assembly (13, 23, 33), wherein the method comprises the following steps : - providing a part comprising an annular portion (17, 27, 37); - forming a support zone (18, 28, 38) on one face of the annular portion (17, 27, 37) using a shaping tool so that the support zone (18 , 28, 38) protrudes from said face of the annular portion (17, 27, 37), the support zone (18, 28, 38) being configured to serve as a support point for the multi-disc assembly (13 , 23, 33) of the multi-plate clutch (10, 20, 30), the shaping tool comprising a plurality of punches each extending over an angular sector, the punches being spaced from each other so that the support zone (18, 28, 38) is formed in a plurality of projecting portions each extending over an angular sector, the projecting portions being separated from each other by intermediate zones each forming, between two consecutive projecting portions, a path allowing an oil passage. 12. The manufacturing method according to claim 11, wherein 5 the step of forming the support zone (18, 28, 38) is carried out by stamping or calibration. 13. The manufacturing method according to claim 12, wherein during the step of forming the support zone (18, 28, 38) by calibration, a vertex (19) of the protruding portions is hardened, the vertex hardened ( 19) presenting a 10 thickness less than a thickness of part of the annular portion (17, 27, 37) radially on either side of said vertex (19).