FR3105324A1 - SUB-ASSEMBLY FOR WET CLUTCH MECHANISM AND WET CLUTCH MECHANISM COMPRISING SUCH SUB-ASSEMBLY - Google Patents

Abstract

SUBASSEMBLY FOR WET CLUTCH MECHANISM AND WET CLUTCH MECHANISM INCLUDING SUCH SUBASSEMBLY The invention relates to a sub-assembly (10) for a clutch mechanism (1) (E1, E2) of the multi-disc type, comprising: - a veil (3) of entry of couple, - a torque input disc carrier (14, 24), of axis X of revolution, comprising a splined axial extension (25) arranged to support the multi-disc assembly of a wet clutch (E1, E2), a the ends (27) of the axial extension (25) being integral in rotation with the web (3), and - a stiffening element (90) fixed axially relative to the input disc holder (24), said stiffening element (0) radially covering the other free end of the input disc holder (14, 24) according to an annular overlap zone (R), wherein the sub-assembly (10) comprises means for retaining (55) in centrifugation of the free end (26) of the input disc holder (14, 24), the retaining means (55) being disposed on the overlap zone (R). Figure for abstract: FIGURE 1

Description

“WET CLUTCH MECHANISM SUB-ASSEMBLY AND WET CLUTCH MECHANISM INCLUDING SUCH SUB-ASSEMBLY”

The context of the present invention is that of wet clutch mechanisms, in particular for motor vehicle transmissions, the latter being for example a heavy goods vehicle, a public transport vehicle, or an agricultural vehicle. The invention relates to a subassembly for a wet clutch mechanism. The invention also relates to a wet clutch mechanism comprising such a sub-assembly, as well as a double wet clutch mechanism comprising such a sub-assembly.

In the state of the art, wet clutch mechanisms are known, each comprising a torque input means intended to be coupled to a crankshaft, a torque output shaft, a wet clutch of the multi-disc type, as well as at least one actuator making it possible to generate a force to configure the corresponding clutch in an engaged or disengaged configuration. In the case where the actuator is integrated into the wet clutch mechanism, the actuator comprises an axially movable piston which is controlled in displacement by means of a control chamber with which is associated a balancing chamber delimited at least by a balancing cover.

Each multi-disc clutch comprises flanges connected in rotation to an input disk carrier forming the torque input means and friction disks connected in rotation to output disk carriers. In known manner, the input disc carrier further comprises a splined axial extension integral with the torque input means and arranged to receive the flanges of the wet clutch, for example on its outer diameter. To reduce the bulk and lighten the overall weight of the clutch mechanism, there is a need to reduce the dimensions of the input disc carrier, in particular by reducing the quantity of material and/or the thickness of its axial extension.

When operating on a vehicle, the clutch mechanism is subjected to high rotational speeds, which causes deformation of the input disc carrier by centrifugation. The free end of the axial extension of the disc carrier tends by deformation to expand, in particular if the latter is of thinner thickness, thus opening radially on the outside of the mechanism and on the flanges that he supports. Such deformation changes spline geometry, clearance and cooperation between parts, which is problematic for axial displacement of the flanges and seriously affects the overall operation of the multi-plate clutch between its engaged and disengaged positions.

In addition, the heating of the multi-disc assembly requires the routing of a cooling fluid. It is known, to lubricate a wet double clutch mechanism, to introduce a cooling fluid in the center of the double clutch mechanism, by bringing the oil from a hydraulic pump to the multi-disc assemblies, to maintain constant their mechanical properties and thermal. But the circulation of the cooling fluid is complex, undergoing pressure drops before arriving at the multi-disc assemblies by centrifugation, as well as fluid leaks, for example at the ends of the inner disc carrier. This affects the lubrication and overall operation of the dual clutch mechanism.

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.

Indeed, according to a first aspect, the invention proposes a subassembly for a clutch mechanism of the multi-disc type, comprising:
– a couple entrance veil,
– a torque input disc carrier, with axis X of revolution, comprising a splined axial extension arranged to support the multi-disc assembly of a wet clutch, one of the ends of the axial extension being integral in rotation with the veil, and
– a stiffening element fixed axially with respect to the input disc carrier, said stiffening element radially covering the other free end of the input disc carrier according to an annular overlap zone,
in which the sub-assembly comprises means for retaining the free end of the input disk carrier in centrifugation, the retaining means being arranged on the overlap zone.

The subassembly for the clutch mechanism according to the invention has the advantage, during operation of the clutch mechanism, of retaining the free end of the centrifugal input disc carrier by means of a stiffening element, being given that the stiffening element radially covers the free end of the input disc carrier, at the level of its annular overlap zone.

Thanks to the centrifugation retaining means of the subassembly, the free end of said disc carrier subjected to a centrifugal force is held rigidly in the annular overlap zone. The connection between the two parts then forms a centrifugation retaining means for the free end of said disc carrier, at the level of the overlap zone. The retaining means allows radial and angular retention of the free end of the disc carrier relative to the axially fixed stiffening element.

The deformation of the splined axial extension of the input disc carrier is limited, regardless of the dimensions of said input disc carrier. The variation in diameter at the free end of the inlet disc carrier is limited when the sub-assembly is subjected to high rotational speeds, during operation of the clutch mechanism on the vehicle. It is also possible to reduce the quantity of material or thickness of the axial extension, to reduce the weight and the overall cost of the entry disc carrier. By "centrifugation retaining means", we mean any type of retaining means (welding, cooperation of shapes, etc.) formed jointly between two parts to prevent centrifugation of one of them.

Such an annular overlap zone has the advantage of optimizing the arrangement of the parts of the sub-assembly, to form said retaining means with a small quantity of material, of parts and/or to reduce the size of the sub-assembly.

• « 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 and in the claims, 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 subassembly in accordance with the first aspect of the invention advantageously comprises one or more improvements described below, the technical characteristics forming these improvements being able to be taken alone or in combination:

– The retaining means can be produced by cooperation of shapes between the disc carrier and the stiffening element. This cooperation of shapes has the advantage, for the stiffening element and the free end of the disc carrier, of forming together a centrifugation retaining means for retaining the free end of the disc carrier subjected to a centrifugal force. Preferably, the end of the disc carrier and the stiffening element can be mounted by interference fit, that is to say with a precise fit, for example without radial play. In this way, the cooperation of shapes forming the retaining means makes it possible to radially and rigidly hold the free end inside the overlap zone;

– The stiffening element may include an annular crown at the level of the annular overlap zone, which guarantees better rigidity in centrifugation to retain the free end of the disc holder. Preferably, the stiffening element can be of the annular type, that is to say extending circumferentially around the axis X;

– Advantageously, retaining fingers can extend axially from the free end of the axial extension of said disc carrier, said fingers of the disc carrier being inserted into the stiffening element and partly forming said retaining means. Preferably, the retaining fingers can be formed in the extension of the axial extension of said disc carrier. The retaining finger can come from the bottom of the groove of the free end. As a variant, the retaining finger can come from a tooth of the spline of the free end;

– Preferably, the fingers of the free end of said disc carrier can be formed by stamping and cutting, for example from a sheet intended to form said input disc carrier. Two adjacent spaced fingers of the free end of the disc holder can be connected to each other by a notch;

– In a particular case, the retaining finger may for example be of a fluted shape, to facilitate their interlocking and promote better indexing in the stiffening element, during the tight assembly of the parts. Alternatively, the retaining finger can form, for example, a pre-centering lug;

– The retaining fingers of the input disc carrier can be distributed angularly evenly around the X axis. Alternatively, the retaining fingers can be distributed angularly irregularly;

– The input disc carrier may include an even number of retaining fingers. Alternatively, the input disc carrier may include an odd number of retaining fingers. In general, the number of retaining fingers can be between three and forty fingers, preferably this number is included - in a first example - between four and ten retaining fingers, or - in another example - between ten and thirty-five restraining fingers. This number, forming in part said centrifugation retaining means, is advantageously chosen according to the size of the fingers or the centrifugal force (maximum speed of rotation) applied to the sub-assembly;

– In a first example, the free end of the disc holder can be nested radially in the stiffening element, said disc holder passing through openings made in the annular ring of the stiffening element. The advantage of such interlocking of the inner disc carrier and the stiffening part is to be axially compact, which optimizes the arrangement of said parts. Nested shapes use less material and also reduce axial space. This preserves the edge or the circular contour of the annular crown, which has the advantage of better rigidity in centrifugation.

– More precisely, the openings can be made in the radially outer end of the stiffening element. Therefore, the free end of the inner disc carrier can be nested radially in the radially outer end of the stiffening element;

– In such a situation, the openings can be located opposite the retaining fingers of the disc carrier, in other words said retaining fingers can pass through openings made in the stiffening element. Preferably, the openings and/or the fingers can be of identical size. Alternatively, the apertures and retaining fingers may be of different sizes.

– The openings can present an open or closed outline, see present a combination of openings with an open outline and openings with a closed outline. In general, the openings may have the same area;

– In a second example, the stiffening element may comprise a flange arranged radially outside the free end of the input disc carrier, the flange forming part of said retaining means. In other words, the rim can be formed on the outer periphery of the stiffening element. Therefore, the rim can partially surround the free end of the disc carrier axially, in order to form said means for retaining the free end in centrifugation;

– Preferably, the internal diameter of the flange of the stiffening element is slightly smaller than the external diameter of the free end of the inlet disc holder. Therefore, the end of the flange can be radially in contact on the free end of the disc carrier, to form part of the retaining means.;

– The annular flange can form a rigid hook, extending circumferentially continuously around the X axis, in order to solidly link the stiffening element to the disc carrier;

– Said rim can be of the annular type. Said rim may take the form of a continuous flange. The advantage of such an annular flange and/or of such a continuous flange is to reduce the loss of material, while being arranged to center and retain the end of the inlet disc holder during centrifugation. In this way, a free space is delimited over 360 degrees around the X axis forming a fluid conduit capable of conveying the lubricating oil to the right of the multi-disc assembly of the clutch, crossing said disc carrier. Such a flange therefore makes it possible to minimize any risk of fluid leakage at the free end of the inlet disc holder, guaranteeing better sealing of the sub-assembly;

– Preferably, the rim and/or the flange can be formed by stamping and/or bending the stiffening element, for example by stamping a single sheet. Material removal operations, for example cutting or drilling, are replaced by a stamping and/or bending operation. The manufacturing steps are simplified for the stiffening element;

– In a third example, the retaining means can be made by welding the inlet disc carrier to the stiffening element. Welding advantageously allows a certain clearance between parts before final assembly. In this way, the solder partly forms the means for retaining the free end in centrifugation. In general, such a weld has the advantage of creating a permanent and unremovable connection forming the retaining means, to radially and rigidly hold the free end of the disc carrier, inside the overlap zone. The stiffening element can therefore be integrally linked to the entry disc carrier;

– Preferably, the free end of the disc holder can be fixed by welding to a flat bearing face of the stiffening element. Therefore, the overlap zone has the advantage of reducing the geometric defects of the assembly by welding;

– More specifically, the weld can be made in the axial direction, between the radial edge of the free end of the disc holder and a radial bearing face of the stiffening element. In this situation, the weld can extend circumferentially continuously or discontinuously around the X axis, for example in the form of a weld bead extending angularly at an angle between 25° and 360°;

– Alternatively, the weld can be made in the radial direction, between an axial bearing face of the stiffening element and the spline of the free end of the entry disc holder. In particular, the solder may comprise a plurality of solder elements, for example solder points that can be placed at the bottom of each tooth of the free end of said disc carrier;

– The retaining means can be a spot or resistance weld, which ensures better metallic continuity and tightness of the retaining means, without deformations of the welded parts. Alternatively, the retaining means may be a weld with added material. As a variant, the retaining means can be a weld by capacitor discharge, in particular for a bump weld, without harming the initial geometry of the parts. Circularity defects are also reduced;

– As a variant, the retaining means may be laser welding by transparency, the free end of the disc carrier and the stiffening element being welded together by a bead of laser welding by transparency placed in the overlap zone. During the welding operation, the stiffening element is then interposed axially between the beam of the laser source and the free end of the disc carrier, without damaging the neighboring parts, for example the multi-disc assembly;

– Advantageously, the entry disc carrier, the entry veil and the stiffening element can form a so-called unitary subassembly, which can be assembled beforehand, without interfering with the assembly of the other components of the mechanism. wet clutch. Such a sub-assembly can thus simplify their handling, their transport and their mounting, of the clutch, and allow for example the step of mounting the multi-disc assembly on the axial extension of the input disc carrier;

– The stiffening element may comprise a continuous outer contour of circular shape. Therefore, said weld can extend angularly continuously around the X axis;

– Alternatively, the stiffening element may include a serrated or fluted outer contour. That is to say, it includes tooth or groove reliefs on its radially outer part. The teeth or splines of the stiffening element can be arranged opposite those of the splined free end. The serrated or splined outer contour of the stiffening element can therefore be dimensioned identically to the spline of the free end of the inlet disc carrier, in order to allow the discs to pass. Such a serrated outer contour thus allows the discs of the multi-disc assembly to be mounted on the axial extension of the disc carrier, without blocking or interfering with the geometric constraints of the stiffening element;

– The weld can be discontinuous and distributed angularly around the X axis, according to a regular distribution. In such a situation, the weld comprises a plurality of weld elements, each positioned on the top of the spline of the free end, in other words substantially close to the outer diameter of the splined input disc carrier;

– The sub-assembly may also comprise a central hub with an X axis of rotation. The stiffening element can be integrally linked to the central hub, so as to fix it axially. For example, the stiffening element can be riveted or welded to said central hub;

– Advantageously, the stiffening element can be integrally linked to the entry veil, so as to axially fix the said stiffening element. For example, the stiffening element can be riveted to the entrance wall. From then on, the rivet can act as a spacer to leave room for the cooling fluid to pass. In other words, the rivet can form a flange to create a sufficient free axial space, and thus guarantee a certain level of flow and passage of the cooling fluid;

– Alternatively, the stiffening element can rest on the entry wall, so as to make said stiffening element axially fixed. As a variant, the stiffening element may be able to bear or to be pressed against a third part of the clutch mechanism, for example against an elastic return device for a piston of said clutch.
In these two situations, the advantage of this axial holding by support is to eliminate any risk of additional stresses, in the event of defects in the concentricity of the parts (resulting from the stages of manufacture or assembly of the parts);

– The stiffening element may comprise bosses capable of bearing against a neighboring part of the clutch mechanism, for example capable of bearing against the inlet veil. The advantage of these bosses made on the stiffening element is to be kept axially away from the inlet veil, so as to form the free axial space for the fluid.

– Advantageously, the stiffening element may comprise an annular skirt capable of partially forming the balancing chamber of the wet clutch. In such a situation, the stiffening element can be a balancing cover;

– More specifically, the annular skirt may comprise on its cylindrical surface a seal arranged to rub on the cylindrical portion of the first piston. The cylindrical surface of the annular skirt can be formed on its inner or outer periphery;

– The seal can be molded onto the annular skirt of the cover. As a variant, the seal may for example be of the lip seal type;

– Bosses can be made on the inside diameter or on the radially inside end of the stiffening element. More precisely, the bosses can be provided on the annular skirt of the balancing cover. Preferably, the series of bosses can be regularly distributed angularly around the axis X, the bosses participating in the formation of the fluidic channel, through the free space which extends continuously over 360 degrees around the X-axis;

– Alternatively, the bosses of the stiffening element can rest on a support plate or a central plate of an elastic return device, comprising for example springs;

– Advantageously, the axial retention of the stiffening element can be achieved by welding the stiffening element to the torque input web, in particular by spot welding the bosses of the stiffening element;

– The sub-assembly may comprise a cooling fluid passage channel, said fluid passage channel being formed by cooperation of shapes between the retaining means, the stiffening element and the internal wall of the inlet veil. In this way, the sub-assembly releases a direct space which is provided in the center of the double clutch and in particular in line with the multi-disc assemblies, that is to say radially below the axial extension. The advantage of such a sub-assembly is to define a direct and rectilinear fluid circulation up to the axial extension of the disc carrier, in order to promote the best possible flow of the fluid, without loss of flow, for example at the right the multi-plate clutch assembly;

– More precisely, part of the fluid passage channel can be delimited axially between, on the one hand, the internal wall of the inlet veil and, on the other hand, the external wall of the stiffening element and the means of retained in centrifugation of the free end;

– More specifically, another part of the fluid passage channel can be delimited axially between the internal wall of the stiffening element and the internal wall of the inlet veil;

– The input disc carrier may comprise an annular portion extending radially outwards from the axial extension along a plane perpendicular to the axis X. In a particular case, such a portion has the advantage of offsetting fixing, for example by moving away from the X axis the weld between the input disc carrier and the input veil;

– Alternatively, the input disc carrier may comprise an annular portion extending radially inwards from the axial extension along a plane perpendicular to the X axis;

The invention also relates, according to a second aspect, to a clutch mechanism of the multi-disc type comprising at least:
– a sub-assembly repeating all or part of the characteristics mentioned previously in the first aspect, comprising said torque input disc carrier;
– a torque output disc holder,
– a clutch comprising a multi-disc assembly interposed radially between the torque input and output disc carriers, arranged to selectively couple a driving shaft to at least one driven shaft.

The clutch mechanism in accordance with the second aspect of the invention advantageously comprises at least one of the improvements below, the technical characteristics forming these improvements being able to be taken alone or in combination:

– According to a first embodiment, the clutch mechanism according to the second aspect of the invention is of the type of a simple clutch. For example, the clutch mechanism may be of the multi-disc type K0 cut-off clutch, controlled to selectively couple a driving shaft to a driven shaft;

– According to a second embodiment, the clutch mechanism according to the second aspect of the invention is of the type of a double wet clutch. That is, the wet double-clutch mechanism includes:
– a first clutch and a second clutch respectively of the multi-disc type, in rotation around an X axis of rotation, controlled to selectively couple a driving shaft to a first driven shaft and to a second driven shaft,
– a first torque input disc carrier supporting the multi-disc assembly of the first wet clutch and integrally connected to the torque input disc,
– a second torque input disc carrier supporting the multi-disc assembly of the second wet clutch and integrally connected to the torque input disc, said first and second disc carriers being integral in rotation relative to each other other,
wherein the double wet clutch mechanism comprises at least one subassembly taking all or part of the characteristics mentioned above in the first aspect.

- For any of the embodiments described above, the first and second clutches - according to a first version - are arranged in an axial configuration, the first clutch being located next to the second clutch. Consequently, the two clutches can comprise a first and a second sub-assembly taking up all or part of the characteristics mentioned previously in the first aspect. The two clutches of the multi-disc type are thus located at the same radial distance relative to the axis X of rotation.
In such a situation, the first and second torque input disc carriers may each be a torque input disc carrier of two subassemblies. The first input disk carrier of the first clutch and/or the second input disk carrier of the second clutch can form said input disk carrier of a first and/or of a second sub-assembly, taking up all or part of the characteristics mentioned above in the first aspect.
More explicitly, the first input disc carrier of the first clutch can form an input disc carrier of a first subassembly incorporating all or part of the characteristics mentioned previously in the first aspect.
Alternatively or in addition, the second input disc carrier of the second clutch can form an input disc carrier of a second subassembly incorporating all or part of the characteristics mentioned above in the first aspect.

– According to a second version compatible with any of the variant embodiments described above, the clutch mechanism comprises two clutches of the multi-disc type configured according to a radial configuration, a first clutch being located radially outside of a second clutch . In such a situation, the first input disc carrier of the first clutch may be an outer torque input disc carrier. The second inner torque entry carrier may be an inner torque entry carrier.
More precisely, the second input disk carrier, called the inner torque input disk carrier, can form the said input disk carrier of the subassembly, taking up all or part of the characteristics mentioned previously in the first aspect;

Depending on the first or second version, the clutch mechanism is a wet double clutch mechanism;

– Advantageously, the clutch mechanism is a triple-clutch mechanism or hybrid clutches, intended more particularly to equip vehicles with robotised gearboxes;

Various embodiments of the invention are provided, integrating according to all of their possible combinations the various optional characteristics set out here.

Other characteristics and advantages of the invention will become apparent through the description which follows on the one hand, and several embodiments given by way of indication and not limiting with reference to the appended diagrammatic drawings on the other hand, on which :
- There describes an axial sectional view of a wet clutch mechanism according to a first embodiment of the invention;
- There describes a perspective view in axial section of the wet clutch mechanism with the subassembly according to the first embodiment of Figure 1;
- There describes an exploded perspective view of the wet clutch mechanism with the subassembly according to the first embodiment of Figure 1;
- There describes a detailed perspective view of the input disc carrier of the subassembly according to the first embodiment of Figure 1;
- There describes a perspective view in axial section of the wet clutch mechanism with the sub-assembly according to a second embodiment of the invention close to FIG. 1;
- There describes an exploded perspective view of the wet clutch mechanism with the subassembly according to the second embodiment of Figure 5;
- There describes a perspective view in axial section of the wet clutch mechanism with the subassembly according to a third embodiment of the invention close to FIG. 1;
- There describes an exploded perspective view of the wet clutch mechanism with the subassembly according to the third embodiment of Figure 7;

Of course, the characteristics, the variants and the different embodiments of the invention can be associated with each other, according to various combinations, insofar as they are not incompatible or exclusive of each other.

In particular, variants of the invention may be imagined comprising only a selection of characteristics described below in isolation from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention from to the state of the prior art. In particular, all the variants and all the embodiments described can be combined with each other if nothing prevents this combination from a technical point of view.

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

Unless otherwise indicated, the verbs "include", "present" or "understand" must be interpreted broadly, that is to say not limiting. The thickness is measured along the X axis of rotation. In the figures, the elements common to several figures retain the same reference.

In the remainder of the description which follows and in the claims, the terms will be used, without limitation and in order to facilitate understanding thereof:
- "front" or "rear" in a direction defined with respect to an axial orientation determined by an axis of rotation X of the sub-assembly or of the clutch mechanism, the "rear" designating the part located to the right of the figures, on the side of a gearbox for example, and “the front” designating the left part of the figures, on the side of an internal combustion engine for example; And;
- "inside/internal" or "outside/external" with respect to the axis of rotation X and following a radial orientation, orthogonal to the axial orientation, the "inside" designating a proximal part of the axis of rotation X and "outside" designating a distal portion of said axis of rotation X.

FIG. 1 shows a first embodiment of a wet-type double-clutch mechanism 1, in accordance with the first aspect of the invention. The wet double-clutch mechanism 1 is of the multi-disc type and has a main axis of rotation X. The double-clutch mechanism 1 is integrated on a transmission chain comprising a transmission coupled in rotation to said double-clutch mechanism.

In the example illustrated in FIGURE 1, the clutch mechanism 1 for the torque transmission system comprises two clutches E1, E2 configured according to a "radial configuration", the first clutch E1 being located radially outside or inside. above a second E2 clutch.

In a variant not shown, the two clutches E1, E2 can be configured in an "axial configuration", that is to say arranged axially one beside the other along the X axis; The first clutch E1 is then located in front of the second clutch E2, the two clutches E1, E2 being located at the same radial distance relative to the axis of rotation X.

The clutch mechanism 1 is here a double wet clutch mechanism 1, controlled to selectively couple said shaft leading to a first transmission shaft A1 and to a second transmission shaft A2 driven via the first clutch E1 or the second clutch E2. Such a double-clutch mechanism 1 comprises around the axis X at least one input element 2, said torque input element configured to be coupled in rotation to a drive shaft, here the motor shaft (not shown) . The input element 2 is located in front of the wet double clutch mechanism 1.

Preferably, the first and second driven transmission shafts A1, A2 are coaxial and intended to be coupled in rotation to the transmission, such as for example a gearbox of the type fitted to motor vehicles.

In the examples illustrated, the inlet element 2 generally having an "L" shape, comprises an annular elongation 1 of radial orientation and also an axially oriented part formed by an inlet hub 4. The elongation ring 1 and the inlet hub 4 are integral, connected here by a plug 9. In a variant not shown, the annular elongation 1 and the inlet hub 4 form one and the same part, for example of the forged type, or fixed together by welding such as laser welding by transparency and/or riveting.

The input element 2 further comprises a torque input veil 3, intended in particular to couple in rotation the two clutches E1, E2 to the transmission. More precisely, the first clutch E1 and the second clutch E2 are arranged to alternately transmit a so-called input power – a torque and a rotational speed – from the input shaft, to one of the two output shafts. transmission A1, A2, depending on the respective configuration of each clutch E1 and E2 and via an input veil 3. The first clutch E1 and the second clutch 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.

In the context of the invention, the first driven shaft is driven in rotation when said first clutch E1 is closed and the second driven shaft is driven in rotation when said second clutch E2 is closed. Thus, the clutch mechanism 1 is arranged to be able to selectively couple in rotation the motor shaft to a first or to a second transmission shaft A1, A2 via one of the two clutches E1, E2.

Preferably, the first clutch E1 and the second clutch E2 are in the open state, also called "normally open", and are actuated selectively in operation by a control device (not shown) of the wet clutch mechanism to pass from the open state to the closed state.

The first clutch E1 and the second clutch E2 are respectively controlled by a first actuation system 30 and a second actuation system 40, which will be described later. Each actuation system 30, 40 is arranged to be able to configure their corresponding clutch E1, E2 in any configuration between the engaged configuration and the disengaged configuration. The first and second actuation systems 30, 40 respectively of the first clutch E1 and of the second clutch E2 thus make it possible to selectively control each clutch E1, E2 between its engaged configuration and its disengaged configuration.

The input hub 4 is, for example, connected in rotation via splines to the output of a damping device (such as a double damped flywheel) whose input is connected, in particular via from a flywheel, to the input drive shaft formed by a crankshaft which is driven in rotation by a motor, for example a heat engine fitted to the motor vehicle. The annular elongation 1 and the veil 3 of entry are two parts added one on the other. Alternatively, the annular elongation 1 and the inlet veil 3 can be a one-piece piece. In the examples illustrated, the annular elongation 1 comprises, at its outer radial end of axial orientation, teeth 6 which extend radially outwards and which rest on the web 3 of torque input. The input hub 4 meanwhile located radially inside relative to the veil 3 input. A circlip 5 is used to lock the assembly axially.

In the examples illustrated, the input veil 3 is common to the first and second clutches E1, E2, and it is integrally connected to a first input disc carrier of the first clutch E1, called the external input disc carrier 14 , and also to a second input disc carrier of the second clutch E2, said internal disc carrier 24 input.

In the examples considered, the outer disc carrier 14 comprises a main body of axis X of revolution, called the splined axial extension 15, which supports the multi-disc assembly of the first wet clutch E1. In particular in FIGURE 1, the outer disc carrier 14 is made in one piece with the inlet veil 3, so as to form a single piece of one-piece type, in order to reduce the assembly steps.

In the examples illustrated, the inner disc carrier 24 of entry comprises a main body of axis X of revolution, called the splined axial extension 25, which supports the multi-disc assembly of the second wet clutch E2. The annular axial extension 25 extends axially between a first free end 26 and a second fixed end 27.

The free end 26 of the splined axial extension 25 comprises a radially inner bore or edge 251, the inner periphery of which defines a first inner diameter D1 along the axis X. The splined axial extension 25 comprises a radially outer edge 252, of which the outer periphery defines the outer diameter D2 along the X axis. The free end 26, and subsequently the axial extension 25, extends radially between the radially inner 251 and outer 252 edges, the diameter D1 is smaller than the diameter D2 .

The multi-disc assembly of the first clutch E1 comprises a plurality of first friction elements, such as for example flanges 11, integrally connected in rotation to the input web 3 as well as to the motor shaft, and on the other hand friction discs 12, such as discs 12 comprising friction linings, integrally connected in rotation to a disc support 13, also called a torque output disc carrier 13, as well as to the transmission shaft A1. The friction discs 12 are individually axially interposed between two successive flanges 11. It is specified here that no disk 11, 12 can be supported by the free end 26 of the axial extension 25, in order to guarantee its retention and the correct operation of the clutch E2.

Similarly, the multi-disc assembly of the second clutch E2 also comprises flanges linked in rotation to the input disc 3 and friction discs linked in rotation to a disc support 23, also called output disc carrier 23.

The clutches E1, E2 each comprise between two and seven friction discs, preferably four friction discs. The output disc carrier 23 of the second clutch E2 is connected in rotation by meshing with the friction discs and by a splined connection with said second driven shaft. The output disc carrier 23, in the shape of a revolution around the X axis, also comprises an axial extension arranged to receive the multi-disc assembly of the wet clutch E2 and an annular portion extending radially inwards from the axial extension along a plane perpendicular to the X axis.

In the examples considered, the second fixed end 27 of said inner disc carrier 24 is splined and it is integral in rotation with the veil 3. In particular, the second fixed end 27 forms a radially outer annular portion, which extends circumferentially from continuously around the axis X. Therefore, said fixed end 27 extends radially from the axial extension 24 towards the inside of the mechanism 1, according to a plane perpendicular to the axis X.

Alternatively, the fixed end 27 of the inner disc carrier 24 may be formed by a radially internal annular portion, extending radially from the axial extension 24 towards the inside of the mechanism, along a plane perpendicular to the axis X. In a variant not shown, the end 27 can extend circumferentially in a discontinuous manner, and then comprises a series of lugs forming a discontinuous axial extension range.

The inlet veil 3 and the fixed end 27 of the inner disc carrier 24 are fixed together by welding. In a variant not shown, the splined fixed end 27 of the inner disc carrier 24 and the inlet veil 3 can be inserted one into the other, by cooperation of complementary splines, so as to bind integrally in rotation and without weld the splined axial extension 25 with the veil 3.

The first transmission shaft A1 is rotationally coupled to the input shaft. The first transmission shaft is driven by the input shaft in rotation when the first clutch E1 is configured in a so-called engaged position for which the plurality of flanges 11 is coupled in rotation to the plurality of friction discs 12. Alternatively, the first transmission shaft A1 is decoupled in rotation from the input shaft when the first clutch E1 is configured in a so-called disengaged position for which the plurality of flanges 11 is decoupled in rotation from the plurality of friction discs 12. The second transmission shaft A2 is coupled analogously to the input shaft via the second clutch E2.

The torque output disc carrier 13 of the first clutch E1 is connected in rotation by meshing with the friction discs 12 and by a splined connection with said first driven shaft. The torque output disc carrier 13 of the form of revolution around the axis X comprises an axial extension arranged to receive the multi-disc assembly of the wet clutch E1, an annular portion extending radially inwards from the axial extension along a plane perpendicular to the axis X. The output disc carrier 13 generally has an "L" shape, the inner radial end of which is secured to a first output hub 120, preferably by laser welding by transparency, friction or capacitor discharge. The first output hub 120 comprises radially inside axial splines arranged to cooperate with complementary splines located on the first transmission shaft A1, so as to achieve a rotational coupling.

The output disc carrier 23 generally has an "L" shape, the inner radial end of which is preferably secured by laser welding by transparency, friction or capacitor discharge to a second output hub 220. The second output hub 220 comprises radially inside axial splines arranged to cooperate with complementary splines located on the second transmission shaft, so as to achieve a rotational coupling.

Preferably, each actuation system 30, 40 comprises:
- A pressure chamber 31, 41 arranged to receive a pressurized hydraulic fluid from a high pressure hydraulic circuit. Each pressure chamber 31, 41 makes it possible to generate the axial force which makes it possible to configure the corresponding clutch E1, E2 in its engaged configuration;
– a force transmission member 32, 42 movable axially or in translation along the X axis, partly extending radially outside the pressure chamber 31, 41, so as to transmit the axial force of the pressure chamber 31, 41;
– an actuating piston 34, 44, axially movable inside the pressure chamber 31, 41 and connected to the force transmission member 32, 42, said actuating piston 34, 44 being arranged at the inside the pressure chamber 31, 41 and intended for the actuation of the clutch mechanism 1 to configure the clutch E1; And
– a balancing chamber 33, 43 located opposite the pressure chamber 31, 41 with respect to the actuating piston 34, 44. Each balancing chamber 33, 43 makes it possible to generate the axial force which allows configure the corresponding clutch E1, E2 in its engaged configuration.

In order to also limit the axial size of the clutch mechanism 1, the actuation systems 30, 40 are linked to their respective clutch E1, E2 via their corresponding force transmission member 32, 42. Each force transmission member 32, 42 comprises:
- A first part 32a, 42a extending radially outside the corresponding pressure chamber 31, 41 in order to engage or disengage the corresponding clutch E1, E2;
- A second part 32b, 42b located radially inside the first part 32a, 42a and collaborating with the pressure chamber 31, 41 and the balancing chamber 33, 43 corresponding;
- A third part 32c, 42c connecting the first part 32a, 42a and the corresponding second parts 32b, 42b;

In particular, the second part 32b, 42b of the member 32, 42 consists of a radial extension surface. The third part 32c, 42c of the member 32, 42 comprises at least one axial extension bearing. Said first, second and third parts of each force transmission member 32, 42 are made in a single piece, for example by sheet metal stamping. In general, the first force transmission member 32 is arranged to transmit a first axial force, exerted parallel to the longitudinal axis X, to the first clutch E1 via its first part 32a collaborating with the friction elements ( flanges 11 and friction discs 12) of said first clutch E1, and of its second part 32b collaborating with a force generator to configure the first clutch E1 in one of the configurations detailed above.

At its first part 32a, the first force transmission member 32 comprises external supports 32d, in other words actuating fingers 32d, which extend axially forward AV in order to be able to press the flange 11 at the end of the multi-disc assembly of the first clutch E1 against a friction disc 12 on the one hand, and against an external reaction means 18 formed directly in the input web 3 on the other hand. In the example illustrated in FIGURE 1, the external supports 32d are discontinuous. The external supports 32d extend parallel to the longitudinal axis X towards the front AV and through openings provided through the entrance veil 3, in particular through the external disc carrier 14 of the first clutch E1.

In a manner analogous to the operation of the first piston described above, the second force transmission member 42 is arranged to transmit a second axial force, exerted parallel to the longitudinal axis X, to the first second clutch E2 via its first part 42a working with the friction elements (flanges and friction discs) of said second clutch E2, and its second part 42b working with a force generator to configure the second clutch E2 in one of the configurations detailed above. At its first part 42a, the second force transmission member 42 comprises external supports 42d, in other words actuating fingers 42d, which extend axially towards the rear AR. The supports 42d bear against the end flange of the multi-disc assembly of the second clutch E2. In FIGURE 1, the supports 42d form a continuous crown.

In the examples illustrated, the external supports 42d extend axially (towards the rear AR) in order to be able to press the multi-disc assembly of the second clutch E2 against an external reaction means 28, formed here directly in the inlet veil 3.

The elastic return of these actuators is generated by elastic return devices 60, 70. Each actuation system 30, 40 thus comprises an elastic return device 60, 70, arranged to generate an axial force opposing the movement of the actuator. force transmission member 32, 42 corresponding to engage the clutch E1, E2 corresponding. This makes it possible to push back or automatically return the force transmission member 32, 42 to the disengaged position, corresponding to an open state of the clutch. In this position, each actuating piston 34, 44 axially releases the corresponding multi-disc assembly which then no longer transmits torque in the direction of the first or second driven shaft A1, A2.

In the examples illustrated, the double-clutch mechanism 1 comprises two elastic return devices 60, 70, of axis of revolution X, respectively for the first clutch E1 and the second clutch E2, which make it possible to generate a sufficient axial force by compression. to restore the corresponding actuating piston 34, 44 and their corresponding clutch to their initial so-called disengaged configuration. Each elastic return device 60, 70 comprises a series of helical compression springs 63, 73, distributed angularly around the axis X and arranged to bear respectively on the first or the second force transmission member 32, 42 by via a first annular bearing plate 61, 71, as shown in FIGURE 1.

Thus, the first support plate 61, 71 of the elastic return device respectively supports the series of coil springs 63, 73 and presses on the first force transmission member 32, 42. The series of coil springs 61, 71 is supported by a second annular bearing plate 62, 72 also of annular shape. The second support plate 62, 72 of the elastic return device 60 thus supports the series of helical springs 63 and thus presses respectively on the cover 80, 90.

In the example illustrated in FIGURE 1, the first actuating piston 34 of the first clutch E1 and the actuating piston 44 of the second clutch E2 of said dual-clutch mechanism 1 move axially in opposite directions to pass for example from the disengaged position to engaged position. Indeed, the pressure chambers 31, 41 of the present invention exert axially opposite actuating forces on said actuating pistons 34, 44. In particular, the actuating force of the first force transmission member 32 is directed axially forward AV while the actuating force of the second force transmission member 42 is directed axially rearward AR.

In FIGURE 1, the first actuating piston 34 of the first clutch E1 is axially movable, here from rear to front between a disengaged position and an engaged position which correspond respectively to the open and closed states of the first clutch E1. The first actuating piston 34 is arranged axially between the pressure chamber 31, located axially at the rear rear and the balancing chamber 33 located axially at the front AV. The first piston 32 takes the form of a corrugated sheet and is curved axially rearward AR at its outer radial end.

Similarly, the second actuating piston 44 is axially movable, here from front to rear between a disengaged position and an engaged position which correspond respectively to the open and closed states of the second clutch E2. The second actuating piston 44 is arranged axially between the pressure chamber 41, located axially at the front front and the balancing chamber 43 located axially at the rear rear.

In particular in FIGURE 1, the internal part of each force transmission member 32, 42 is located radially in the corresponding pressure chamber 31, 41, thereby forming the actuating piston 34, 44. In other words, each force transmission member 32, 42 and its corresponding actuating piston 34, 44 form one and the same piece.

In particular in FIGURE 1, the outer diameter of the pressure chamber 31 of the first clutch E1 is smaller than the outer diameter of the pressure chamber 41 of the second clutch E2. In addition, the inside diameter of the pressure chamber 31 of the first clutch E1 is equal to the inside diameter of the pressure chamber 41 of the second clutch E2. The inside diameter of the balancing chamber 33 of the first clutch E1 is equal to the inside diameter of the balancing chamber 43 of the second clutch E2.

During its operation on a vehicle, the mechanism 1 is subjected to high speeds of rotation. To avoid any expansion or deformation of material, the free end 26 of the centrifuged inner disc holder 24 is retained radially by means of a stiffening element 90. More specifically, the stiffening element 90 is radially supported on the free end 26. Therefore, the free end 26 is fixed axially with respect to the stiffening element 90. More particularly, the stiffening element 90 is fixed axially with respect to the inner disc carrier 24 and it radially covers the first free end 26 of the inner disc carrier 24, along an annular overlap zone R.

Consequently, the stiffening element 90 radially retains the free end 26 of the inner disc carrier, at the level of the overlap zone R. The inlet veil 3, the inner disc carrier 24 and the stiffening element 90 thus form a sub-assembly 10 for retaining the centrifuged free end 26 of the inner disc holder.

The stiffening element 90 is a one-piece part, called cover 90, that is to say of annular shape around the axis X and which is extremely rigid with respect to the free end 26 of the inner disc carrier 24 The stiffening element 90 comprises at least one rigid annular portion 91 capable of coming to rest radially on the free end 26.

The rigid portion 91 is located in the overlap zone R, and it extends in the radial direction between an outer periphery, called the rigid outer contour 901, and an inner periphery, called the inner contour 902. The outer contour 901 defines a third diameter D3 along the X axis.

In the first embodiment, the outer diameter of the rigid portion 91, third diameter D3 of the stiffening element 90 is slightly greater than the outer diameter D2 of the free end 16 of the inner disc carrier 24. In addition, the stiffening element 90 is interposed axially between the inlet web 3 and the free end 26 of the inner disc carrier. For example, the rigid portion 91 extends at least partly along a plane perpendicular to the X axis.

Alternatively, the rigid portion 91 of the stiffening element 90 can be inclined angularly in the radial direction with respect to the axial extension 25.

Advantageously, the stiffening element 90 further comprises a continuous annular portion 93, here of cylindrical shape called annular skirt 93. The annular skirt 93 extends from said rigid annular portion 91, over 360 degrees around the axis X, so as to tightly delimit a free space.

Advantageously, the annular skirt 93 partly forms a balancing chamber 43 of the second clutch E2. In the examples illustrated, the stiffening element 90 thus forms a so-called balancing cover of the balancing chamber 43. Each balancing cover 80, 90 of the elastic return device 60, 70 partly forms or delimits the corresponding balancing chamber 33, 43, more precisely by delimiting the closure between the balancing chamber 33, 43 with the inlet veil 3 and/or with the force transmission member 32, 42.

In particular in FIGURE 1, the balancing covers 83 and 93 of the first and second elastic return devices 60, 70 are different. More specifically, the covers 80, 90 of the first and second elastic return devices 60, 70 are different.

Alternatively, the covers 80, 90 can be identical, in particular in the case of an architecture of two clutches in axial configuration.

In a variant not shown, the stiffening element 90 can be another third part of the clutch mechanism 1, for example a support plate of one of the return devices of the first and/or the second piston 32, 42.

In the examples illustrated, the balancing chamber 33 of the actuation system 30 of the clutch E1 is thus advantageously delimited:
– axially rearward AR, by the first actuating piston 34;
– axially forward AV, by the veil 3 and/or by the central hub 7;
– radially inwards, by a cylindrical bearing surface of the central hub 7;
– radially outwards, by a closure zone between the cylindrical bearing surface 82 of the balancing cover 80 and the first actuating piston 34.

Similarly, the balancing chamber 43 of the actuation system 40 of the clutch E2 is thus advantageously delimited:
– axially forward AV, by the second actuating piston 44;
– axially towards the rear AR, by the stiffening element 90;
– radially inwards, by a cylindrical bearing surface of the central hub 7;
– radially outwards, by a closure zone between the annular skirt 93 of the stiffening element 90 and the first actuating piston 44.

By way of non-limiting example, the stiffening element 90 is made in part by stamping a sheet.

In the examples considered, the annular overlap zone R is delimited radially between the rigid outer 901 and inner 902 contours of the stiffening element 90. Preferably, it is delimited radially between the rigid outer contour 901 and the inner wall of the skirt ring finger 93.

Advantageously, the overlap zone R is delimited radially between the first inside diameter D1 of the outer disc carrier 14 and the third diameter D3 of the stiffening element 90 along the axis X. Advantageously, the overlap zone R can be delimited radially by the rigid annular portion 91.

The sub-assembly 10 further comprises a means 55 for retaining the free end 26 of the inner disc holder 24 in centrifugation, which is arranged in the annular overlap zone R. In other words, the stiffening element 90 and the free end 26 of the inner disc carrier 24 are linked, covered and/or matched thanks to said retaining means 55.

Advantageously, said rigid annular portion 91 comprises an annular crown 910 of the stiffening element, which extends circumferentially around the axis X, which guarantees better rigidity of the retaining means 55 in centrifugation.

In particular, the force transmission members 32, 42 here each comprise an annular and continuous recess, in order to form a uniform flat surface. For the force transmission member 32, the third part 32c is an axial recess (towards the front) inside which is, at least partly, housed the elastic return device 60. More specifically, the recess 32c of the force transmission member 32 houses in particular the first support plate 61 and the coil springs 63 of the elastic return device 60.

Similarly, the third part 42c is an axial recess (towards the rear) of the force transmission member 42, inside which is, at least partly, housed the inner disc carrier 24 and a part of an annular skirt 93 of the stiffening element 90.

The sub-assembly 10 further comprises a central hub 7, in other words support hub 7 for one or more clutches, with an axis of rotation X. The inlet web 3 is solidly fixed by welding to the central hub 7. Thus, the central hub 7 supports the first and second clutches E1, E2 via the veil 3 of common input. The central hub 7 is therefore coupled in rotation to the input hub 4 of the double-clutch mechanism 1. When the input hub 4 is coupled to a motor shaft driven in rotation by the crankshaft of an engine, as described previously , then the central hub 7 is driven by a rotational movement similar to that of the motor shaft.

To selectively control the change of state of the first clutch E1 and of the second clutch E2 of the double-clutch mechanism 1, the control device manages the supply of fluid, for example oil, for each actuation system 30, 40 The control device is connected to the central hub 7 which has channels 99 partly visible on the sectional planes of FIGURE 2. To do this, a hydraulic pump is connected to the central hub 7 on its fluidic channels 99. The mechanism 1 thus comprises a hydraulic cooling circuit 9, called the first low-pressure hydraulic circuit, which is formed of fluidic channels 99 and a fluidic channel 50, in order to ensure the cooling and the lubrication of the clutches E1, E2 during their operation. functioning. On the other hand, the mechanism 1 also comprises a second hydraulic circuit (not visible in the figures), called high pressure, in order to supply hydraulic fluid to the actuation systems 30, 40 to control each clutch E1, E2, plus precisely in order to supply one of the pressure chambers 31, 41 making it possible to generate an axial force on one of the clutches E1, E2.

The sub-assembly 10 further comprises a free axial space, which is provided at the center of the double clutch to circulate the cooling fluid in line with the multi-disc assemblies of the two clutches E1, E2, i.e. radially below the axial extension 25 .

Advantageously, the sub-assembly 10 further comprises a channel 50 for the passage of cooling fluid, direct and rectilinear, formed by said free space. Said channel 50 is formed by cooperation of shapes between the retaining means 55, the stiffening element 90 and the radially internal wall of the inlet veil 3. This fluid circulation of the channel 50, up to the axial extension of the door -discs, favors a better flow of the cooling fluid.

In the examples illustrated, a part of the channel 50, close to the axial extension 25, is delimited axially between, on the one hand, the internal wall of the inlet veil 3 and, on the other hand, the external wall of the skirt annular 93, the free end 26 and said retaining means 55. In particular, another part of the channel 50, remote from the axial extension 25, is delimited axially between the internal wall of the annular skirt 93 and the internal wall of the veil 3 input.

In the examples illustrated, the stiffening element 90 further comprises an annular radial bearing 97, defining said internal wall of the annular skirt 93, and the internal periphery of which defines the internal contour 902 of the stiffening element 90. In particular , said annular radial bearing surface 97 is not by default fixed solidly to a neighboring part, but it is free and maintained axially by pressing or by support, in order to eliminate any risk of additional stresses in the event of concentricity defects of the parts ( resulting from the manufacturing or assembly stages of the parts). To fix the stiffening element 90 axially, the annular radial bearing 97 is pressed axially against the second bearing plate 72 of the elastic return device 70. In other words, the radial bearing 97 supports the second bearing plate 72 of the device spring return 70.

By centrifugation effect, the cooling oil is evacuated to the outside of the wet clutch mechanism 1, in particular by passing through the two multi-disc assemblies. In order to evacuate the fluid outside the mechanism 1, orifices 240, 140 for fluidic evacuation are also arranged in line with the multi-disc assemblies respectively on the inner 24 and outer 14 disc holders. The openings are formed in the grooves and grooves of the disc carriers, and are regularly distributed angularly around the X axis.

Similarly, the cover 80 illustrated in FIGURE 1 comprises a radial bearing 87 which supports the second support plate 62 of the elastic return device 60. Preferably, the radial bearing 87, 97 of the cover 80, 90 is continuous on 360 degrees around the X axis.

For each clutch E1, E2, the helical springs 63, 73 (previously compressed or crimped between the two support plates within the device) press the second support plate 62, 72 onto the radial bearing surface 87, 97. Consecutively , the second support plate 72 presses the stiffening element 90 axially against the free end 26 of the inner disc carrier 24. In this way, the stiffening element 90 is centered in centrifugation on the disc carrier interior 24 and the production of the retaining means 55 is thus guaranteed. The stiffening element 90 is thus retained with the first support plate 71. Similarly, the cover 80 is retained with the first support plate 61. In this way, each first bearing plate 61, 71 is held axially with respect to the corresponding second bearing plate 62, 72.

In a variant not shown, retaining means can be formed on the cover 80, 90 and on the first support plate 61, 71. This is another way of fixing the stiffening element 90 axially with respect to the device. elastic return device 60, 70. For each elastic return device 60, 70, these retaining means can cooperate jointly, thanks to a form cooperation between the first support plate 61, 71 and the cover 80, 90, for example in support or in abutment or by snap-fastening.

For example, the radial bearing 87, 97 may comprise a plurality of connecting arms 84, spaced apart circumferentially and angularly distributed around the axis X. The attachment means may be any possible type of shape cooperation, for example a combination of connecting arms 84, hooks, notches, holes, recesses of material, or any type of cooperation between male and female parts.

In such a situation, the first support plate 61, 71 can be hooked onto the stiffening element 90. For each clutch E1, E2, the first support plate 61, 71 and the cover 80, 90 are thus held together axially, the elastic return device 60, 70 forms a unitary subassembly, in other words, an elastic return device that can be preassembled or mounted beforehand.

In an example illustrated in FIGURE 1, the elastic return device 60 is arranged axially between the input web 3 and the force transmission member 32 of the first clutch E1. The cover 80 of the elastic return device 60 is thus in axial support on the input disc carrier 8. More specifically, the radial bearing surface 81 of the cover 80 is in axial plane support on the input disc carrier 8 of the clutch E1. As a result, the cover 80 of the elastic return device 60 is free to move radially with respect to the input disc carrier 8 of the clutch E1.

The elastic return device 70 is arranged axially between the support hub 7 common to the clutches E1, E2 and the force transmission member 42 of the first clutch E2. In a variant not shown, the stiffening element 90 can rest on the support hub 7. Alternatively, the radially inner end of the stiffening element 90, called radial bearing 97, can be fixed axially by welding or riveted on the support hub 7.

In another variant not shown, the radial bearing 97 of the stiffening element 90 can be integrally linked to the inlet veil 3, for example by rivet, which makes it possible to define a free space between the two riveted parts, for the channel 50 fluidic.

Alternatively, said radial bearing surface 97 of the stiffening element can rest on the inlet web, so as to make said stiffening element axially fixed. In such a situation, the radial bearing surface 97 may include bosses capable of coming to rest on the inlet veil 3. Said bosses provided on the stiffening element 90 make it possible to keep the radial bearing surface 97 and the internal wall of the inlet veil 3 axially separated, in order to create the free axial space to provide part of the fluidic channel 50. Preferably, the bosses are regularly distributed angularly around the X axis, so as to form a part of the fluidic channel 50 extending continuously over 360 degrees around the X axis.

In the first and second embodiments, the retaining means 55 is produced by cooperation of shapes between the inner inlet disc carrier 24 and the stiffening element 90. More specifically, the free end 26 and the portion 93 annular form together by cooperation of shapes said retaining means 55 in centrifugation, in order to radially and rigidly maintain the free end 26 of the disc carrier (subjected to a centrifugal force). In the examples illustrated in FIGURES 1 to 6, the free end 26 of the disc carrier and the stiffening element 90 are mounted by interference fit, that is to say with a precise fit, for example without radial play, so as to increase the rigidity of the retaining means 55.

In the first embodiment, the free end 26 of the inner disc carrier 24 is radially nested in the stiffening element 90. More specifically, the stiffening element 90 comprises a plurality of retaining openings 56, which are formed in the overlap zone R, and through which passes the free end 26 of the axial extension 25. The openings 56 are formed in the radially outer end of the stiffening element 90, in other words they are formed on the rigid portion 91, preferably through the annular ring 910. The advantage of such interlocking of the inner disc carrier and the stiffening part is to be axially compact, which optimizes the arrangement of the retaining means 55 , and reduces the amount of material needed for this retainer.

Consequently, the openings 56 of the stiffening element 90 partly form the retaining means 55. Preferably, each opening 56 has a closed contour, preferably of identical shape and dimensions, that is to say having the same area. The openings 56 preferably have rounded corners, in order to limit the concentrations of mechanical stresses. This preserves the edge or the rigid circular contour of said annular ring 910, to guarantee better rigidity of the retaining means 55 in centrifugation.

In the example of FIGURES 1 to 4, the stiffening element 90 comprises an even number of openings 56, here a total of twenty-eight openings 56 made from the annular ring 910 and which are regularly distributed angularly, at an angle about twelve degrees. Alternatively, the stiffening element 90 may comprise an odd number of openings 56, for example three openings 56 arranged at an angle of 120 degrees.

In general, the number of openings 56 can comprise at least two openings 56, preferably angularly regularly distributed. Advantageously, the number of openings 56 can be between two and forty openings 56, preferably between four and thirty retaining openings 56 forming the retaining means 55.

In the first embodiment, the inner disc carrier 24 comprises a plurality of retaining fingers 260 extending axially from the free end 26 of the axial extension 25. The retaining fingers 260 are formed in the extension of the axial extension 25. Consequently, the fingers 260 of the inner disc carrier are inserted into the stiffening element 90, more precisely through said openings 56. Consequently, the fingers 260 of the free end 26 form part of the retaining means 55.

In FIGURES 1 to 4, the inner disc carrier 24 comprises an even number of fingers 260, here a total of twenty-eight fingers 260 provided from the axial extension 25 and angularly distributed regularly at an angle of approximately twelve degrees. The fingers 260 are arranged through the openings 56 of the axially movable cover 90, preferably one finger 260 for a corresponding opening 56. In other words, a finger 260 is placed inside an opening 56 of the cover 90 and it is dimensioned according to the corresponding opening. The fingers 260 are opposite the openings 56 and they are therefore here angularly regularly distributed around the axis X of rotation.

In FIGURES 3 to 4, two adjacent fingers 260 of the free end 26 are interconnected by a connecting spoke or a notch 261. resting on the annular ring 910. A notch 261 is defined by at least one spline tooth of the free end 26. The free end 26 comprises an alternation of notches 241 and retaining fingers 260.

Generally, the fingers 260 are formed by cutting the free end 26, during the formation of the inner disc carrier 24. The free end 26 and the axial extension 25 are formed by stamping and cutting, for example from a sheet intended to form said inner disc carrier 24. The retaining finger 260 is made from material and it is formed from the bottom of the groove of the free end 26, that is to say in the extension of the diameter interior D1 of the axial extension 25.

In a variant not shown, the finger 260 can come from a tooth of the spline of the free end 26, in other words, in the extension of the outer diameter D2 of the axial extension 25.

In an example illustrated in FIGURE 1, the elastic return device 60 of the clutch E1 is thus located outside the balancing chamber 33 of the actuation system 30. In other words, the coil springs 63 are outside of the balancing chamber 33 of the actuation system 30. The externalization of the elastic return device thus allows the force transmission member 32 of the first clutch to receive during its actuation a force opposite to that of the actuation whose origin of its vector is located radially close to the radius of contact between the force transmission member 32 and all of the clutch discs of the clutch 1. This makes it possible to help the piston to remain as perpendicular to the axis as possible during actuation, reducing chattering.

Alternatively, the elastic return device 70 of the clutch E2 is located inside the balancing chamber 43 of the actuation system 40, that is to say integrated into the balancing chamber 43. Otherwise said, the coil springs 73 are in the balancing chamber 43.

In the first embodiment, the sub-assembly 10 guarantees the correct operation of the corresponding actuation system 30, 40, given that sealing of the balancing chamber 33, 43 of the corresponding actuation system is guaranteed by the presence of two seals, including:
– a seal 83, 93, said first seal, located on the force transmission member 32, 42, more particularly, at the limit or at the level of the third part or recess 32c, 42c of the organ. The seal 83, 93 of the transmission member 32, 42 rubs on the annular skirt 83, 93, as described previously; And ;
– a second seal 74, 94 located between the inner radial end of the force transmission member 32, 42, more precisely the second part 32b, 42b of the force transmission member 32, 42, and the cylindrical bearing surface of the input torque support hub 7, as described previously.

In the first embodiment, the seal 83, 93 rubs against the internal bore of the cylindrical bearing surface 82, 92 of the corresponding cover 80, 90. In other words, the seal 83, 93 is arranged radially inside the cylindrical surface 82, 92 of the cover 80, 90. Advantageously, in order to allow sealing despite a differential speed of rotation between the member transmission 32, 42 and the corresponding cover 80, 90, the first seal 83, 93 is of the type of a dynamic seal, such as for example a lip seal. In a variant not shown, the seal 83, 93 can be molded onto the force transmission member 32, 42.

Similarly, the sub-assembly 10 guarantees the correct operation of the corresponding actuation system 30, 40, since sealing of the pressure chamber 31, 41 of said actuation system is guaranteed by the presence of two seals. sealing, including:
- A third seal 36, 46 located between a closing part 39, 49 and the transmission member 32, 42, more particularly, at the level of the recess 32b, 42b of the transmission member 32, 42;
– a fourth seal 37, 47 located between the transmission member 32, 42 and the cylindrical bearing surface of the support hub 7.

Advantageously, in order to allow sealing despite a differential speed of rotation between the transmission member 32, 42 and the support hub 7, the third seal 36, 46 is of the type of a dynamic seal, such as for example a lip seal.

Advantageously, in order to allow sealing despite a differential speed of rotation between the transmission member 32, 42 and the closure part 39, 49, the fourth seal 37, 47 is of the type of a dynamic seal , such as for example a lip seal.

Thus, during operation of the transmission system to control the corresponding clutch E1, E2, an inner radial end slides axially along a radially outer face of the cylindrical bearing surface of the support hub 7. The second seal 74, 94 guarantees the preservation of the seal during this sliding. More particularly, when the hydraulic fluid pressure increases in the pressure chamber 31, 41 – by supply via the high pressure hydraulic circuit – the transmission member 32, 42 slides in the direction of the axis of symmetry Y, i.e. front AV for the clutch E1, or towards the rear AR the clutch E2, thus compressing the flanges of the clutch E1, E2 against its friction discs. Conversely, when the hydraulic fluid pressure decreases and/or when a force exerted by the elastic return device 60, 70 in the balancing chamber 33, 43 is greater than that of the pressure chamber 31, 41, the transmission member 32, 42 slides in the corresponding opposite direction, thus separating the flanges of the clutch E1, E2 from its friction discs.

In order to guarantee optimal operation, the mechanism 1 with double clutch 1 also comprises three bearings 10, 95, 96:
– a first axial bearing 95 interposed axially between the output disc carrier 13 of the clutch E1 and the output disc carrier 23 of the clutch E2, in order to be able to transmit an axial load between the two output disc carriers 13, 23 which can rotate at different speeds when the first and second clutches E1, E2 are configured in a different configuration;
- A second axial bearing 96 interposed between the output disc carrier 13 of the clutch E2 and the central hub 7;
- a radial bearing 10 interposed in an axially intermediate position between an axial front end AV of the input hub 4 and the first output hub 120 solidly connected to the output disc carrier 13, in order to withstand the radial forces of the hub of input 4 and/or of the input veil 3 despite the different speeds of rotation at which the input shaft and the first transmission shaft A1 can respectively rotate.

Advantageously, the bearing 10 is a ball bearing member and the bearings 95, 96 are rolling bearings with a first and second disk between which a plurality of rolling bodies are arranged. In a variant not shown, the radial bearing 10 can be located in an axially intermediate position between an intermediate bearing surface of the input hub 4 and one of the transmission shafts A1, A2.

In a variant not shown, the wet clutch mechanism 1 can be of the single-clutch or triple-clutch mechanism type or else the clutch mechanism is a cut-off clutch for hybrid transmissions, intended more particularly to equip vehicles with a gearbox robotic gears.

There has been described in FIGURES 5 to 6, a second embodiment of the invention substantially similar to the first embodiment, with the exception of the fact that the stiffening element 90 comprises a flange 920 which is disposed radially to the exterior of the free end 16 of the inner disc carrier 24. This cooperation of shapes between the flange 920 and the free end 16 forms said retaining means 55. More specifically, the flange 920 is made from material and is extends from said rigid portion 91. Rim 920 is located in said overlap zone R.

Therefore, said flange 920 forms the radially outer periphery of the stiffening element 90. In this way, the flange 920 radially surrounds the free end 16 and also partly axially the free end 16. This makes it possible to center and to retain the free end 16 in centrifugation. Said flange 920 partly forms said retaining means 55 in centrifugation of the free end 16 of the inner disc holder 24.

In the second mode, the inner periphery of the rim 920 forms the outer contour 901. Preferably, the outer diameter of the rim 920 defines the third outer diameter D3 along the X axis. In addition, the inner periphery of the rim 920 forms an edge connection or a cavity with the rigid portion 91.

Preferably, the outer diameter of the rim 920 defines a fourth inner diameter D4 along the axis X. Therefore, the end of the rim 920 is radially in contact on the free end 26 of the said inner disc carrier 24, to form part the retaining means 55. The end of the flange 920 is delimited between the third and fourth diameters D3, D4. Diameter D4 is smaller than diameter D3.

In a variant not shown, said rim 920 may be of the circumferentially discontinuous type around the axis X, and therefore comprises a plurality of retaining fingers formed from the rigid portion 91 or formed from the annular crown 910 of the stiffening element 90. Said retaining fingers forming the flange 920 are preferably distributed angularly regularly around the axis X.

In such a situation, the internal diameter of the flange 920, called fourth diameter D4 of the stiffening element 90 can be less than the external diameter D2 of the free end 16 of the internal disc carrier 24. In this example, the fingers of retainer of the stiffening element 90 can be, for example, centered or in radial support in the bottom or hollow part of the spline of the free end 26.

In the second mode, said rim 920 is of the circumferentially continuous or annular type, in the form of a continuous collar around the axis X. In this way, a support is defined over the entire surface of the free end 26 and a space is delimited. free closed over 360 degrees around the axis X, to form a fluidic channel 50 conveying the lubricating fluid to the right of the multi-disc assemblies of the two clutches E1, E2. Such a flange thus makes it possible to minimize any risk of fluid leakage at the free end 26 of the inner disc carrier 24, which guarantees better sealing of the subassembly 10 and in particular of the channel 50.

In such a situation, the inside diameter of the flange 920, called the fourth diameter D4 of the stiffening element 90, is slightly smaller than the outside diameter D2 of the free end 16 of the inner disc carrier 24. In this example, the collar of the flange 920 is centered or in radial support on the top of the groove of the free end 26.

Advantageously, the rim 920 of the stiffening element 90 forms a rigid hook, which extends circumferentially in a continuous manner around the axis X, in order to solidly link the stiffening element 90 to said inner disc holder 24. Similarly , the collar or rim 920 is formed by stamping and/or bending the stiffening element 90.

There has been described in FIGURES 7 to 8, a third embodiment of the invention substantially similar to the first embodiment, except that the retaining means 55 is produced by welding 100 of the inner disc carrier 24 on the stiffening element 90. Therefore, the stiffening element 90 is integrally connected to the inner disc carrier 24.

More precisely, the weld 100 fixedly connects the rigid portion 91 to the free end 16, at the level of a circumferentially continuous planar bearing surface of the rigid portion 91. Consequently, the annular overlap zone R makes it possible to reduce geometric assembly defects by welding 100.

In this way, the weld 100 partly forms the retaining means 55 in centrifugation of the free end 16, and is carried out by advantageously allowing a certain play between parts before the final assembly. In general, such a weld 100 has the advantage of creating a permanent and unremovable connection forming the retaining means 55, to radially and rigidly hold the free end 16 inside the overlap zone R.

In the third mode, the rigid portion 91 of the stiffening element 90 comprises a serrated or fluted outer contour 930. That is to say, it comprises reliefs 930 of tooth or groove 931 on its rigid portion 91 The teeth or splines 931 of the stiffening element 90 are arranged facing the spline of the splined free end 16 .

Advantageously, the top of a relief 931 forms the outer contour 901. Preferably, the outer diameter of the relief 931 defines the third outer diameter D3 along the axis X. The hollow of a relief 931, called the hollow of the contour external serrated or splined 930, defines the fourth internal diameter D4 along the axis X. The diameter D4 is less than the diameter D3.

In such a situation, the serrated or splined outer contour 930 is delimited between the third and fourth diameters D3, D4. The serrated or splined outer contour 930 is radially in contact on the free end 26 of said inner disc carrier 24, to form part of the retaining means 55.

In this third mode, the fourth diameter D4 of the stiffening element 90 is substantially equal to the outer diameter D2 of the free end 16 of the inner disc carrier 24. Similarly the third diameter D3 of the stiffening element 90 is substantially equal to the inner diameter D1 of the free end 16 of the inner disc carrier 24.

Consequently, the serrated or grooved outer contour 930 of the stiffening element 90 is dimensioned identically to the groove of the free end 16, in order to allow the discs to pass when they are mounted on the axial extension 25. A such a serrated outer contour 930 allows the disks 21, 22 to be mounted on the axial extension 25, without blocking or interfering with the geometric constraints of the stiffening element 90. Consequently, the weld 100 is circumferentially discontinuous around the axis X, according to an even distribution.

In such a situation, the weld 100 comprises a plurality of welding elements, positioned on the top of the groove of the free end 16, in other words substantially close to the outer diameter D2 of the inner disc holder 24 grooved. Preferably, the weld 100 is made in the axial direction, between the radial edge of the free end 16 and a radial bearing face of the rigid annular portion 91 of the stiffening element 90. Alternatively, the weld 100 can be made in the radial direction, between an axial bearing face of the stiffening element and the spline of the free end of the entry disc carrier.

In FIGURES 7 to 8, the weld 100 extends circumferentially in a discontinuous manner around the axis X, for example in the form of a weld bead. In other words, the weld 100 comprises a plurality of welding elements, for example welding points that can be placed at the bottom of each tooth of the free end of said disc carrier.

Advantageously, the retaining means 55 is formed in part by a spot weld 100 with addition of material. Alternatively, the retaining means may be a resistance weld, which ensures better metallic continuity and tightness of the retaining means, without deformation of the welded parts. In a variant not shown, the retaining means 55 can be welded by capacitor discharge, in particular for welded bumps, without harming the initial geometry of the parts. Circularity defects are also reduced.

Advantageously, the entry disc carrier, the entry veil and the stiffening element form a so-called unitary welded sub-assembly 10, which can be assembled beforehand, without interfering with the assembly of the other components of the mechanism. wet clutch. Such a sub-assembly 10 simplifies their handling, their transport and their assembly, clutch, and allow for example the step of mounting the multi-disc assembly on the axial extension 25 of the input disc carrier.

In a variant not shown, the stiffening element 90 may comprise a continuous outer contour of circular shape. Therefore, said weld 100 can extend angularly continuously around the axis X.

Of course, the present invention is not limited to the embodiments described and represented, provided by way of illustrative and non-limiting example. The torque transmission device according to the invention may comprise a cut-off clutch, of the K0 type, used in hybrid transmissions to couple the heat engine to the electric motor after the vehicle start-up phase. In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

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 fall within the scope of the invention.

Claims (14)

Sub-assembly (10) for clutch mechanism (1) (E1, E2) of the multi-disc type, comprising:
– a torque entry veil (3),
– a torque input disc carrier (14, 24), of axis X of revolution, comprising a splined axial extension (25) arranged to support the multi-disc assembly of a wet clutch (E1, E2), a ends (27) of the axial extension (25) being integral in rotation with the veil (3), and
– a stiffening element (90) fixed axially with respect to the input disc carrier (14, 24), said stiffening element (90) radially covering the other free end of the disc carrier (14, 24) entry according to an annular overlap zone (R),
wherein the sub-assembly (10) includes means for retaining (55) the free end (26) of the input disc carrier (14, 24) in centrifugation, the retaining means (55) being disposed on the overlap zone (R). Sub-assembly (10) according to claim 1, in which the retaining means (55) is produced by co-operation of shapes between the disc carrier (14, 24) and the stiffening element (90). A subassembly (10) according to claim 2, wherein retaining fingers (260) extend axially from the free end (26) of the axial extension (25), said carrier fingers (260) (14, 24) being inserted into the stiffening element (90) and partly forming said retaining means (55). Subassembly (10) according to Claims 2 to 3, in which the free end (26) of the disc carrier (14, 24) is radially imbricated in the stiffening element (90), said disc carrier (14 , 24) passing through openings (56) formed in the stiffening element (90). Subassembly (10) according to Claim 2, in which the stiffening element (90) comprises a flange (920) disposed radially outside the free end (26) of the disk carrier (14, 24) entrance, the flange (920) forming in part said retaining means (55). Subassembly (10) according to claim 1, in which the retaining means (55) is produced by welding (100) the input disc carrier (14, 24) to the stiffening element (90). A subassembly (10) according to claim 6, wherein the weld (100) is formed from the edge of the splines of the free end (26) of the input disk carrier (14, 24) and extends circumferentially continuously or discontinuously around the X axis, for example in the form of a weld bead extending angularly at an angle of between 25° and 360°. A subassembly (10) according to any one of claims 6 to 7, wherein in the stiffening member (90) includes a serrated or splined outer contour (930). Sub-assembly (10) according to one of the preceding claims, in which the stiffening element (90) comprises an annular skirt (93) capable of partially forming the balancing chamber (43) of the wet clutch. A subassembly (10) according to claim 9, wherein the subassembly (10) comprises a coolant passage channel (50), said fluid passage channel (50) being formed by form cooperation between the retaining means (55), the stiffening element (90) and the internal wall of the inlet veil (3). Sub-assembly (10) according to one of Claims 9 to 10, in which the stiffening element (90) comprises bosses capable of coming to bear against a neighboring part of the clutch mechanism (1), for example capable to come to bear on the entrance veil (3). Double wet clutch mechanism (1) comprising:
– a first clutch (E1) and a second clutch (E2) respectively of the multi-disc type, in rotation around an X axis of rotation, controlled to selectively couple a driving shaft to a first driven shaft (A1) and to a second shaft led (A2),
– a first torque input disc carrier (14) supporting the multi-disc assembly of the first wet clutch (E1) and integrally connected to the torque input disc (3),
– a second torque input disc carrier (24) supporting the multidisc assembly of the second wet clutch (E2) and integrally connected to the torque input disc (3), said first and second disc carriers (14, 24) being integral in rotation relative to each other,
wherein the dual clutch mechanism (1) comprises at least one subassembly (10) according to any preceding claim. Double wet clutch mechanism (1) according to claim 12, wherein the clutch mechanism comprises two clutches (E1, E2) of the multi-plate type, configured in an axial configuration, the first clutch (E1) being located axially next to 'a second clutch (E2), the two clutches (E1, E2) of the multi-disc type comprising a first and a second subassembly (10). A double wet clutch mechanism (1) according to claim 12, in which comprises two clutches (E1, E2) of the multi-plate type configured in a radial configuration, a first clutch (E1) being located radially outside of a second clutch (E2), the first input carrier (14) of the first clutch (E1) being an outer torque input carrier, the second inner torque input carrier (24) being a inner torque input discs, and wherein the second inner torque input disc carrier (24) forms said subassembly input disc carrier (10).