FR3122232A1 - Disc carrier assembly and wet clutch including this disc carrier assembly - Google Patents

Abstract

Disc carrier assembly and triple wet clutch including this disc carrier assembly Assembled disc carrier (30) for wet clutch comprising: - a splined hub (31a, 31b, 31c, 31d, 31e, 31f, 31g) with axis of rotation X fitted with an internal torque transmission spline, - a disc support (32a, 32b, 32c, 32d, 32e, 32f, 32g) in the form of revolution around the X axis equipped with an external spline arranged to cooperate with a multi-disc assembly, the disc support (32a , 32b, 32c, 32d, 32e, 32f, 32g) resting axially on the splined hub (31a, 31b, 31c, 31d, 31e, 31f, 31g), - an oil retention cavity (33) concentric with the axis (X), formed at least by the combination of surfaces from the splined hub and the disc support, the splined hub forming an oil supply line (34) opening into the oil retention cavity (33) closed by the internal surface of the disc support. Figure for abstract: Figure 2

Description

Disc carrier assembly and wet clutch including this disc carrier assembly

The present invention relates to an assembled disc carrier and a wet clutch comprising this assembled disc carrier. The invention also relates to a double wet clutch and a triple wet clutch comprising this assembled disc carrier.

The present invention relates to the field of torque transmission chains for motor vehicles, in particular arranged between a combustion engine and a gearbox.

The invention relates more specifically to a triple wet clutch for a motor vehicle of the hybrid type in which a rotating electrical machine is arranged in the torque transmission chain.

In the state of the art, motor vehicles of the hybrid type are known comprising a double wet clutch arranged between an internal combustion engine and a gearbox, a rotating electrical machine as well as a torque cut-off clutch otherwise called "K0 clutch" and an actuating member of this torque cut-off clutch making it possible to couple or uncouple in rotation a crankshaft of the internal combustion engine to a rotor of the rotating electrical machine. Thus, it is possible to cut the internal combustion engine each time the vehicle stops and to restart it thanks to the rotating electrical machine. The rotating electrical machine can also act as an electric brake or provide a surplus of energy to the internal combustion engine to assist it or prevent it from stalling. When the internal combustion engine is running, the electrical machine can act as an alternator. The rotating electrical machine can also drive the vehicle independently of the internal combustion engine.

Such a rotating electric machine can be in line with the double wet clutch, that is to say that the axis of rotation of the rotor of the rotating electric machine coincides with the axis of rotation of the clutches as described in the document EP2517915. As a variant, the rotating electric machine can be offset with respect to the double wet clutch, i.e. the axis of rotation of the rotor of the rotating electric machine is offset from the axis of rotation of the double wet clutch.

In the current developments of hybridization (“hybridization” in English) of motor vehicles, it is required to have a torque transmission chain integrating a source of electrical energy without however this impacting the axial compactness of said transmission chain. transmission. As a result, it was necessary to design a triple wet clutch with radial architecture to supply cooling fluid and pressurized fluid to the various clutches without modifying the size of the torque transmission chain. This search for axial compactness is the basis of the invention.

The radial architecture of this triple wet clutch sometimes makes it difficult to supply cooling fluid, for example oil, to the multi-disc assemblies of the various wet clutches. The oil supply channels are complex to manufacture and do not always guarantee a good distribution of the cooling oil within the clutches. A lack of lubrication and cooling can lead to overheating of the friction discs and subsequently alter the correct transmission of torque.

The invention aims to improve the existing design by benefiting from a triple wet clutch making it possible to reconcile the requirements of axial compactness while guaranteeing a good supply of cooling oil to the clutches.

For this purpose, the invention proposes, according to one of its aspects, an assembled disc carrier for a wet clutch comprising:
- a splined hub with axis of rotation X provided with an internal torque transmission spline,
- a sheet metal disc support in the shape of a revolution around the X axis, provided with an external spline arranged to cooperate with a multi-disc assembly, the disc support resting axially on the splined hub,
- at least one oil supply line,
- an oil retention cavity, annular and concentric with the X axis, formed at least by the combination of surfaces from the splined hub and the disc support,
the splined hub partially or totally forming the at least one oil supply line opening into the oil retention cavity closed by the internal surface of the disk support.

Thanks to this assembled disc carrier architecture, the cooling oil necessary for the proper functioning of the wet clutch first enters the splined hub using the oil supply line, then enters the oil retention cavity before being evacuated within the wet clutch multi-plate assembly. Thus, the flow of cooling oil is efficiently directed within the wet clutch multi-plate assembly.

The oil retention cavity is formed at least from the “splined hub” and “disc support” components, in particular from an external surface of the splined hub and an internal surface of the disc support. The internal and external surfaces can be raw, unmachined surfaces, the combination of shapes of which creates a cavity. The use of components with simple forms of revolution makes it possible to reduce manufacturing costs. The assembled disc carrier then performs the various functions of torque transmission, friction disc support and cooling oil routing in a reduced axial space.

Preferably, the disc support may comprise orifices formed on the external spline and arranged to evacuate the oil contained in the oil retention cavity. The holes can be distributed circumferentially around the X axis and formed on the tops of the outer spline teeth. Thanks to this assembled disc carrier architecture, the flow of cooling oil collected within the oil retention cavity is evenly distributed throughout the wet clutch multi-disc assembly. Thus, the oil retention cavity does not include a space where the cooling oil remains blocked.

Advantageously, the disc support can be fixed to the splined hub by riveting, crimping, welding or force fitting.

Preferably, the oil supply line may form a bend with an axially extending line portion and a radially extending line portion. The radial orientation of the line allows the flow of cooling oil to be directed efficiently through the wet clutch multi-plate assembly.

According to one embodiment, the assembled disc carrier may comprise an annular deflector attached to the splined hub and comprising external toothing cooperating with the profile of the internal surface of the disc carrier, the oil retention cavity being formed by the combination of surfaces from the splined hub, the disc support and the deflector. Advantageously, the oil retention cavity is formed at least from the "splined hub", "deflector" and "disc support" components, in particular from an outer surface of the splined hub, from a flank of the deflector and of an internal surface of the disc carrier. The internal and external surfaces can be raw, unmachined surfaces, the combination of shapes of which creates a cavity.

According to one embodiment, the oil supply line may form a bend with an axially extending line portion formed by combining the surfaces of the splined hub and the baffle and a radially extending line portion formed by surfaces of the splined hub and of the deflector, for example a groove formed in the splined hub cooperating with a side of the deflector.

According to another embodiment, the oil supply pipe may form a bend with an axially extending pipe part formed only by the splined hub and a radially extending pipe part formed by mating the surfaces of the hub splined and the deflector, for example a groove formed in the splined hub cooperating with a side of the deflector.

Advantageously, the deflector can be produced by stamping sheet metal or by plastic injection of synthetic material, for example polyamide plastic of the PA66 type or polyetheretherketone of the PEEK type. These plastics have a high dimensional stability and are resistant to high temperatures.

The invention may have one or other of the characteristics described below combined with each other or taken independently of each other:
- the oil retention cavity may be formed in part by a circumferential groove made on the outer periphery of the splined hub;
- the radially extending pipe part can be formed by combining the surfaces of the splined hub and the disc carrier and the axially extending pipe part is formed only by the disc carrier, for example by using a hole passing through the disk carrier;
- the radially extending pipe part can be formed by drilling the splined hub and the axially extending pipe part can be formed directly in the splined hub by casting or forging;
- the driving parts extending radially and axially can be formed by combining the surfaces of the splined hub and the disc carrier;
- the radially extending pipe part can be formed by combining the surfaces of the splined hub and the deflector;
- the splined hub may comprise a first machined axial bearing surface;
- the splined hub may comprise a second axial bearing surface machined and arranged axially opposite the first axial bearing surface;
- the disc support can press directly on the splined hub;
- the deflector can press directly on the splined hub;
- the splined hub may comprise oil supply lines distributed angularly around the axis X and emerging into the oil retention cavity;
- the splined hub may have a general shape of revolution with a cylindrical base.

Such an assembled disc carrier, according to one or other of the characteristics described above combined together or taken independently of each other, has the advantage, thanks to the use of inserts of annular parts, of reducing costs. Manufacturing. These annular inserts make it possible to form an oil retention cavity at a lower cost and can also fulfill other functions within a wet clutch such as supporting and centering axial bearings.

The invention also relates, according to one of its aspects, to a wet clutch for a torque transmission system comprising:
- A torque input disc carrier arranged to be connected in rotation with a drive shaft along an axis of rotation X;
- A multi-disc assembly comprising friction discs and pressure plates stacked axially and driven in rotation by the torque input disc holder;
- an assembled disc carrier incorporating all or part of the characteristics mentioned above arranged radially inside the multi-disc assembly and arranged to be connected in rotation to a driven shaft.

Preferably, the wet clutch can comprise a central hub with an axis of rotation X, said central hub comprising:
- a cylindrical portion,
- a flange extending radially from the cylindrical portion fixedly connected to the torque input disc holder, and
- at least one cooling oil supply channel formed in the central hub passing through at least the cylindrical portion and emerging axially opposite the oil supply pipe of the assembled disc carrier so that the oil in coming from the central hub can be transferred into the splined hub of the assembled disc carrier and lead into the multi-disc assembly.

Thanks to this wet clutch architecture, the cooling oil supplied by the vehicle is transferred from the central hub to the assembled disc carrier in a simplified manner. Oil from the central hub is directed axially using the oil supply channel before being transferred to the oil supply line of the assembled disc holder, then enters the retention cavity of oil before being evacuated within the wet clutch multi-plate assembly. Thus, the flow of cooling oil is efficiently directed within the wet clutch multi-plate assembly.

Preferably, the central hub may include several cooling oil supply channels and the assembled disc carrier may include several oil supply lines distributed angularly around the axis X, the outlets of the supply channels cooling oil being arranged over a diameter substantially equal to the diameter of implantation of the inlets of the oil supply lines.

The invention also relates, according to another of its aspects, to a double wet clutch for a torque transmission system comprising:
- A first clutch; And
- a second clutch of the wet clutch type incorporating all or some of the characteristics mentioned above, arranged radially inside the first clutch, the first and second clutches being controlled to selectively couple a shaft leading to a first driven shaft and to a second shaft driven, for example first and second gearbox shafts, and the central hub of the second clutch being common with the first clutch.

Advantageously, the central hub may comprise:
- a flange extending radially beyond the second clutch,
- a first annular cavity arranged on the side of the flange and arranged to receive an actuation piston of the first clutch, and
- a second annular cavity arranged on the same side of the flange as the first annular cavity and arranged to receive an actuation piston of the second clutch,
- at least one oil channel formed in the central hub passing through the flange and opening into one of the annular cavities, said oil channel being separate from the cooling oil supply channel of the multi-disc assembly of the second clutch.

The invention also relates, according to another of its aspects, to a triple wet clutch for a torque transmission system comprising a torque cut-off clutch of the multi-plate type, controlled to selectively couple a shaft driving an electric machine, and a double wet clutch incorporating all or part of the characteristics mentioned above, the torque cut-off clutch being arranged radially beyond the double wet clutch.

Advantageously, the triple wet clutch can comprise the central hub of the double wet clutch which is also common to the torque cut-off clutch, said central hub comprising a third annular cavity disposed radially beyond the other two annular cavities and arranged to receive a piston for actuating the torque cut-off clutch, said central hub comprising an attached drive cover and arranged to be driven in rotation by an electric machine, the drive cover partly forming the third annular cavity.

Preferably, the three annular cavities can be oriented in the same axial direction, in particular in the direction of the driving shaft.

Advantageously, the drive cover can surround the outer periphery of the flange. It is thus possible to arrange the annular cavities associated with the three clutches radially in the same plane.

Preferably, the oil pipes supplying the annular cavities can open out onto the outer periphery of the flange and can be closed by the drive cover. The oil pipes can be distributed angularly around the cylindrical portion of the central hub. In this way, it is possible to seal part of the oil lines without using other expensive components.

Advantageously, the annular cavities of the cut-off clutch, of the first clutch and of the second clutch can follow one another radially in approach to the axis X.

Thanks to this triple wet clutch architecture, the clutches are concentric and arranged radially in the same plane. The axial bulk of such a triple wet clutch within a torque transmission system or a torque transmission chain is thus reduced.

Preferably, the first clutch can be actuated using a first actuating piston, axially movable relative to the first annular cavity of the central hub between an engaged position and a disengaged position of the first clutch, the first piston actuation being controlled in movement by means of a control chamber delimited in part by the flange. In this way, the control chamber of the first clutch is included in the first cavity, the supply of pressurized oil thus taking place as close as possible to the central hub, thus reducing leaks within the triple wet clutch.

Preferably, the second clutch can be actuated using a second actuating piston, axially movable relative to the second annular cavity of the central hub between an engaged position and a disengaged position of the second clutch, the second piston actuation being controlled in movement by means of a control chamber delimited in part by the flange. In this way, the control chamber of the second clutch is included in the second cavity, the supply of pressurized oil thus taking place as close as possible to the central hub, thus reducing leaks within the triple wet clutch.

According to one embodiment, the oil pipe can be produced by drilling successive pipes within the central hub, said pipes being open into each other and arranged to supply pressurized fluid to the clutch control chamber.

According to one embodiment, the drive cover comprises an electrical connection zone capable of being connected in rotation with an electrical machine rotating around an axis parallel to the axis of rotation X. The electrical connection zone can be offset axially of the cut-off clutch and/or of the first and second clutches. The electric machine is then said to be “off-line”.

Preferably, the drive cover may comprise a spline arranged to receive the multi-disc assembly of the cut-off clutch, said spline being made in one piece with the drive cover or attached to the drive cover.

Advantageously, the drive cover may comprise a toothed ring adapted to be connected in rotation with an electrical machine rotating around an axis parallel to the axis of rotation X.

This arrangement makes it possible to position the electric machine according to the space available in the torque transmission chain of the vehicle. This arrangement makes it possible in particular not to have to arrange the electric machine axially following the clutches, which would be negative for the axial compactness. This arrangement makes it possible in particular not to have to arrange the electric machine radially beyond the clutches, which would be negative for the radial compactness.

Alternatively, a chain or a belt can be used to connect the rotating electrical machine to the electrical connection area.

The invention will be better understood, and other aims, details, characteristics and advantages thereof will appear more clearly during the following description of a particular embodiment of the invention, given solely by way of illustration and not limiting, with reference to the appended figures.

- there shows an axial sectional view of a triple wet clutch comprising the assembled disc carrier according to a first embodiment of the invention.

- there shows an isometric view of the assembled disc carrier according to the first embodiment of the invention of the .

- there shows an isometric view of an assembled disc carrier according to a second embodiment of the invention of the invention.

- there shows an isometric view of an assembled disk carrier according to a third embodiment of the invention of the invention.

- there shows an isometric view of an assembled disc carrier according to a fourth embodiment of the invention of the invention.

- there shows an isometric view of an assembled disc carrier according to a fifth embodiment of the invention of the invention.

- there shows an isometric view of the splined hub of the disc carrier assembled according to the fifth embodiment of the invention of the invention.

- there shows an isometric view of an assembled disc carrier according to a sixth embodiment of the invention of the invention.

In the remainder of the description and the claims, the terms "front" or "rear" will be used, without limitation and in order to facilitate understanding, depending on the direction with respect to an axial orientation determined by the main axis X of rotation of the transmission of the motor vehicle and the terms "inner/inner" or "outer/outer" with respect to the X axis and in a radial orientation, orthogonal to said axial orientation.

There is shown in Figures 1 and 2 a first embodiment of an assembled disc carrier 30 for triple wet clutch 1. The triple wet clutch 1 is represented within a motor vehicle torque transmission chain by the through a 100 gearbox housing equipped with two driven torque output shafts A1, A2.

On the , there is a triple wet clutch 1 comprising:
- a multi-disc type K0 torque cut-off clutch, controlled to selectively couple a shaft leading to an electric machine,
- a first torque output clutch E1 and a second torque output clutch E2 respectively of the multi-disc type, controlled to selectively couple the electric machine and/or the driving shaft to a first driven shaft and to a second driven shaft, the first and second clutches E1, E2 being arranged radially one above the other, and
- A central hub 50 supplying oil to the control chambers of the torque cut-off clutch K0, of the first clutch E1 and of the second clutch E2.

The second wet clutch E2 comprises the assembled disc carrier 30 according to the first embodiment of the invention.

The central hub 50 comprises in particular:
- a cylindrical portion 52,
- a flange 53 extending radially from the cylindrical portion 52,
- a first annular cavity 56 disposed on the side of the flange and arranged to receive an actuating piston 15 of the first clutch E1,
- a second annular cavity 55 arranged on the same side of the flange as the first annular cavity and arranged to receive an actuating piston 25 of the second clutch E2,
- a third annular cavity 57 arranged radially beyond the other two annular cavities and arranged to receive an actuating piston 5 of the torque cut-off clutch K0, and
- Oil pipes 54a, 54b and 54c formed in the central hub 50 passing through the cylindrical portion 52 and the flange 53, and emerging separately into the annular cavities.

The annular cavities 57, 56, 55 of the torque cut-off clutch K0, of the first clutch E1 and of the second clutch E2 are oriented in the same direction, for example in the direction of the drive shaft, i.e. say in the direction of the heat engine of the torque transmission chain.

The triple wet clutch 1 comprises around its axis of rotation X at least one torque input element 2 which is connected in rotation to a drive shaft (not shown). Input element 2 is located in front of triple wet clutch 1.

In the first embodiment, the input element 2 generally having an "L" shape, comprises a radially oriented part formed by a torque input veil 3 and an axially oriented part formed by a torque input hub 4. The torque input element 2 is guided in rotation inside a box 101 fixed with respect to the torque transmission chain.

The torque input input element 2 is for example linked in rotation by means of splines formed at the output of a damping device (such as a double damped flywheel, etc.) whose input is linked, in particular by means of a flywheel, to the drive shaft formed by a crankshaft which is driven in rotation by a heat engine fitted to the motor vehicle.

The torque input veil 3 comprises, at its outer radial end, a spline arranged to receive the multi-disc assembly of the torque cut-off clutch K0.

In the example considered, the triple wet clutch 1 further comprises a torque cut-off clutch K0 coupling selectively and by friction the torque input disc 3 and an intermediate disc carrier 81 of the torque cut-off clutch K0 integral in rotation with the splined oil supply hub assembled 50.

The K0 torque cut-off clutch comprises a multi-disc assembly comprising several friction discs 7, equipped with friction linings, integral in rotation with the torque input web 3, several plates 6 respectively arranged on either side of each friction disc 7, integral in rotation with the intermediate disc carrier 81. The torque cut-off clutch K0 is actuated by an actuating piston 5 which is axially movable, here from the rear to the front, between a disengaged position and an engaged position which correspond respectively to the open and closed states of the torque cut-off clutch K0. The actuating piston 5 pinches the friction linings so as to transmit a torque between the torque input web 3 and the intermediate disc carrier 81.

The plates 6 of the multi-disc assembly of the torque cut-off clutch K0 are connected in rotation to the central hub 50 via a spline and the friction disks 7 connected in rotation to the input element 2 .

The central hub 50 comprises a drive cover 80 attached to the outer periphery of the flange 53. The function of the central hub 50 is to transmit the torque within the triple wet clutch 1. For this, the drive cover 80 is integral in rotation with the intermediate disc carrier 81, in this case via a welded connection.

The drive cover 80 includes an electrical connection zone 82 able to be connected in rotation with a rotating electrical machine. In the present case, the electric machine rotates around an axis parallel to the axis of rotation X. The electric machine is said to be "off-line" because it is not concentric with the transmission shaft but aligned according to a parallel shaft. The electrical connection zone 82 is capable of cooperating directly with a pinion of the rotary electrical machine.

The electrical connection zone 82 can be made in the form of a crown capable of being meshed directly by a pinion or indirectly (belt, chain, etc.) of the rotating electrical machine (not visible). The crown may have helical toothing of a shape complementary to the pinion of the rotary electric machine.

The central hub 50 is able to transmit the torque coming from two separate sources, thermal and electrical. When the torque cut-off clutch K0 is closed, the torque from the thermal engine can then be transmitted to the coaxial shafts A1, A2 of the gearbox depending on the closing of one or the other of the first clutch E1 or the second clutch E2.

The first driven shaft A1 is driven in rotation when said first clutch E1 is closed and the second driven shaft A2 is driven in rotation when said second clutch E2 is closed.

The multi-disc assembly of the first clutch E1 comprises plates 11 linked in rotation to a torque input disc holder 10 attached to the central hub 50 and friction discs 12 linked in rotation to an output disc holder 13. The friction discs 12 are individually axially interposed between two successive plates 11.

The 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 A1. The inner radial end of the output disc carrier 13 is secured to a splined output hub.

The multi-disc assembly of the second clutch E2 comprises plates 21 connected in rotation to the torque input disk carrier 10 attached to the central hub 50 and friction disks 22 connected in rotation to an assembled disk carrier 30 made according to the first embodiment of the invention. The assembled disc carrier 30 comprises a splined hub 31a of cylindrical shape with an axis of rotation X provided with an internal spline 310 for transmitting torque and a disc support 32a of the shape of revolution around the axis X. In this first embodiment, the disc support 32a is provided with an external spline 320 arranged to cooperate with a multi-disc assembly and with an internal skirt 321. The internal skirt 321 bears axially on the splined hub 31a. As illustrated on the , the disc support 32a is made from a stamped steel sheet. The disk support 32a is in particular fixed to the splined hub 31a by welding at the level of the internal skirt 321. The welding is in this example continuous over 360°.

As a variant, not shown, the disc support 32a can be fixed to the splined hub 31a by riveting, crimping or force fitting.
The assembled disc carrier 30 of the second clutch E2 is linked in rotation by meshing of the external spline 320 with the friction discs 22 and by the internal spline 310 with said second driven shaft A2. The assembled disc carrier 30 is arranged axially between the output disc carrier 13 of the first clutch E1 and the cylindrical portion 52 of the central hub 50. The assembled disc carrier 30 is interposed axially between two axial bearings. For this, the splined hub 31a comprises a first bearing surface 301 of machined axial bearing and a second bearing surface 302 of machined axial bearing in which the axial bearings are housed. The second bearing surface 302 of the axial bearing is arranged axially opposite the first bearing surface 301 of the axial bearing.

As illustrated on the , the torque input disc carrier 10 comprises an external spline which meshes with the multi-disc assembly of the first clutch E1 and an internal spline which meshes with the multi-disc assembly of the second clutch E2. The torque input disc carrier 10 is securely attached to the central hub 50 via a weld.

In a variant not shown, the internal and external splines meshing with the multi-disc assemblies of the clutches E1 and E2 can be distributed over two separate torque input disc carriers and attached to the central hub.

The triple wet clutch 1 is hydraulically controlled by means of a pressurized fluid, generally oil.

To selectively control the change of state of the torque cut-off clutch K0, of the first clutch E1 and of the second clutch E2, a triple wet clutch control device manages the pressurized oil supply within control chambers separated. The control device is generally integrated into the gearbox housing 100. The control device is connected to the central hub 50 which comprises oil pipes 54a, 54b and 54c under pressure, for example three in number as represented on there . The oil pipes 54a, 54b and 54c are distributed angularly around the cylindrical portion 52 of the central hub 50.

Each of the oil pipes 54a, 54b and 54c consist of substantially radial and axial bores directed in the direction of the control chambers of the torque cut-off clutch K0, of the first and second clutches E1, E2.

For example, the oil pipe 54a whose inlet is located axially close to the flange 53 is associated with the control chamber of the second clutch E2. The oil pipe 54a is produced by drilling successive axial and radial pipes within the central hub 50. The pipes emerge into each other and are arranged to supply pressurized fluid to the control chamber of the second clutch E2. The oil pipe 54a opens into the second annular cavity 55 formed partly by the cylindrical portion 52 of the central hub 50 and partly by an annular insert. In the present case, the annular part attached to the flange of the central hub 50 is part of the torque input disc holder 10 of the second clutch E2. The torque input disc carrier 10 and the second cavity annular insert 55 form one and the same piece.

The second clutch E2 comprises an actuating piston 25 which 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 second clutch E2. The multi-disc assembly of the second clutch E2 is actuated directly by the second actuating piston 25 made from stamped sheet metal. The actuating piston 25 is axially movable relative to the second annular cavity 55 of the central hub 50. The actuating piston 25 is controlled in movement by means of a control chamber delimited in part by the annular insert 10.

The oil pipe 54b machined in the central hub 50 is associated with the control chamber of the first clutch E1. The oil pipe 54b is produced by drilling successive axial and radial pipes within the central hub 50. The pipes emerge into each other and are arranged to supply pressurized fluid to the control chamber of the first clutch E1. The oil pipe 54b opens into the first annular cavity 56.

The first clutch E1 comprises an actuating piston 15 which 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.

In the first embodiment, the oil pipes 54a, 54b and 54c open onto the outer periphery of the flange 53 and are closed by the drive cover 80.

As is known in the operation of a wet clutch, a balancing chamber is associated with each control chamber. The balancing chambers are supplied with fluid, for example cooling fluid. Coolant enters channels separate from oil lines 54a, 54b and 54c. These separate channels are also formed in the central hub 50.

Coolant is also directed through the wet clutch multi-plate assemblies. For this, a cooling oil supply channel 54d is formed in the central hub 50. This channel 54d passes through the cylindrical portion 52 and emerges axially facing an oil supply pipe 34 arranged in the door. -assembled disc 30 so that the cooling oil from the central hub 50 can be transferred into the splined hub 31a of the assembled disc carrier 30 and emerge in the multi-disc assembly of the second clutch E2.

The cooling oil supply channel 54d supplies oil to the assembled disc carrier 30 as well as the balancing chambers of the triple wet clutch 1. The cooling oil supply channel 54d is made by drilling pipes successive axial and radial lines within the central hub 50. The pipes emerge into each other and arranged to supply the balancing chambers with cooling fluid.

For greater efficiency, the central hub 50 has several cooling oil supply channels 54d which communicate with several oil supply lines 34 distributed angularly around the axis X on the splined hub 31a. In the example of the first embodiment, the splined hub 31a comprises eight oil supply lines 34 distributed angularly at 45°.

Each of the oil supply lines 34 forms a bend with an axially extending line portion 36 and a radially extending line portion 35. The radial orientation of the line directs the flow of oil from efficient cooling within the multi-plate assembly of the second clutch E2. The cooling oil supply channels 54d are disposed over a diameter substantially equal to the diameter of the implantation of the axially extending pipe portions 36.

In order to improve the efficiency of the diffusion of the cooling fluid within the second clutch E2, the assembled disc carrier 30 also comprises an oil retention cavity 33, annular and concentric with the axis X, formed by the combination of surfaces from the splined hub 31a and the disc support 32a. The oil retention cavity 33 is in particular formed in part by a circumferential groove made on the outer periphery of the splined hub 31a. Each of the oil supply lines 34 opens into the oil retention cavity 33 closed by the internal surface 38 of the disc carrier 32a.

The disc support 32a comprises orifices 39 formed on the external groove 320 and arranged to evacuate the oil contained in the oil retention cavity 33. The orifices 39 are distributed circumferentially around the axis X and formed on the vertices of teeth of the external spline 320. Thanks to this architecture of the assembled disc carrier, the flow of cooling oil collected within the oil retention cavity is evenly distributed in the multi-disc assembly of the wet clutch.

As illustrated on the , the radially extending pipe part 35 is formed by drilling the splined hub 31a and the axially extending pipe part 36 is formed directly in the splined hub by casting or forging according to the process for obtaining the splined hub 31a.

We will now present other embodiments of the assembled disc carrier 30. All of these assembled disc carriers 30 fulfill the same functions of transmitting torque, supporting the friction discs and conveying the cooling oil to the within a wet clutch.

There presents an assembled disc carrier 30 according to a second embodiment of the invention similar to the first embodiment at least in its general operation.

This second embodiment differs from that exposed with reference to FIGS. 1 and 2 in that the disc support 32b is provided with an external groove 320 arranged to cooperate with a multi-disc assembly and an internal skirt 321 welded discontinuously on the splined hub 31b.

The inner skirt 321 has a central bore 322 which partly forms the oil supply lines 34. As before, each of the oil supply lines 34 forms a bend with an axially extending pipe portion 36 and a radially extending conduit portion 35. In this second embodiment, the radially 35 and axially extending conduit portions 36 are formed by joining the surfaces of the splined hub 31b and the disk carrier 32b.

The disc support 32b rests axially on bosses 313 provided on the splined hub 31b, the discontinuous weld beads being formed at these bosses 313. The bosses 313 are distributed around the cylindrical base of the splined hub 31b. The entry of each of the oil supply lines 34 is between each boss 313.

An oil retention cavity 33, annular and concentric with the X axis, is formed by the combination of surfaces coming from the splined hub 31b and from the disc support 32b. Each of the oil supply lines 34 opens into the oil retention cavity 33 closed by the internal surface 38 of the disc carrier 32b.

This second embodiment has the advantage of mainly using raw surfaces of the splined hub and of the disc support, that is to say not machined, to form the oil supply lines. The manufacturing cost of such an assembled disc carrier is reduced.

There presents an assembled disc carrier 30 according to a third embodiment of the invention similar to the second embodiment at least in its general operation.

This third embodiment differs from that described with reference to the in that the radially extending duct portion 35 is formed by combining the surfaces of the splined hub 31c and the disc carrier 32c, while the axially extending duct portion 36 is formed solely by the disc carrier. The inner skirt 321 of the disc support 32c has a central bore 322 which surrounds the cylindrical base of the splined hub 31c.

Orifices 36 of oblong or circular shapes pass right through the internal skirt 321 and form the axially extending pipe parts 36. In this third embodiment, the disc carrier 32c is welded continuously to the splined hub 31c.

There presents an assembled disc carrier 30 according to a fourth embodiment of the invention similar to the first embodiment at least in its general operation.

This fourth embodiment differs from that described with reference to FIGS. 1 and 2 in that the assembled disc carrier 30 comprises an additional component called a deflector 37 of annular shape and attached to the splined hub 31d. This deflector 37 comprises an external toothing 373 cooperating with the profile of the internal surface 38 of the disc support 32d.

As illustrated on the , the assembled disc carrier 30 comprises an oil retention cavity 33 formed by the combination of surfaces originating from the splined hub 31d, from the disc support 32d and from the deflector 37. Advantageously, the oil retention cavity 33 is formed from an outer surface of the splined hub 31d, a sidewall of the deflector 37 and an inner surface 38 of the disc carrier 32d.

The oil retention cavity 33 is supplied with cooling fluid by a plurality of oil supply pipes 34 distributed angularly around the axis X. Each of the oil supply pipes 34 forms an elbow with a axially extending conduit portion 36 formed only by the splined hub 31d and a radially extending conduit portion 35 formed solely by the splined hub 31d. The pipe parts extending radially 35 are in particular produced by drilling.

The deflector 37 is produced by stamping a sheet of steel. The deflector 37 can be held on the splined hub 31d by fitting or by welding. As a variant, the deflector 37 can be produced by plastic injection of synthetic material, for example polyamide plastic of the PA66 type or polyetheretherketone of the PEEK type.

Figures 6 and 6a show an assembled disc carrier 30 according to a fifth embodiment of the invention similar to the fourth embodiment at least in its general operation.

This fifth embodiment differs from that described with reference to the in that the deflector 37 bears directly against one of the sides of the splined hub 31e so that the oil supply pipe 34 can be formed by combining the surfaces of the splined hub 31e and the deflector 37.

The deflector 37 comprises an external toothing 373 cooperating with the profile of the internal surface 38 of the disc support 32e and an internal bore 370 partly forming the oil supply pipe 34.

As illustrated on the , the assembled disc carrier 30 comprises an oil retention cavity 33 formed by the combination of surfaces originating from the splined hub 31e, from the disc support 32e and from the deflector 37. Advantageously, the oil retention cavity 33 is formed from an outer surface of the splined hub 31e, a sidewall of the deflector 37 and an inner surface 38 of the disc support 32e.

The oil retention cavity 33 is supplied with cooling fluid by a plurality of oil supply pipes 34 distributed angularly around the axis X. Each of the oil supply pipes 34 forms an elbow with a Axially extending pipe portion 36 formed only by the splined hub 31e and a radially extending pipe portion 35 formed by combining the surfaces of the splined hub 31e and the deflector 37.

There illustrates the geometry of the splined hub 31e obtained by casting or forging according to the fifth embodiment of the invention. The splined hub 31e comprises in particular bosses 314 distributed angularly around the axis X having the function of holding and centering the deflector 37. The bosses 314 also make it possible to center the axial bearing. In this embodiment, the assembled disk carrier 30 includes six oil supply lines 34 formed substantially by rough surfaces of the splined hub 31e. Orifices 36 of oblong or circular shapes pass right through the splined hub 31e and form the axially extending conduit portions 36. The orifices 36 open into radially extending grooves 351 which partially form the conduit portions extending radially.

This fifth embodiment has the advantage of mainly using raw surfaces of the splined hub and of the deflector, that is to say not machined, to form the oil supply lines. The deflector 37 is simply supported on the splined hub 31e and held axially in position thanks to the support of the axial bearings distributed on either side of the assembled disc carrier when the latter is assembled in the wet clutch. The manufacturing cost of such an assembled disc carrier is reduced.

There presents an assembled disc carrier 30 according to a sixth embodiment of the invention similar to the fifth embodiment at least in its general operation.

This sixth embodiment differs from that described with reference to FIGS. 6 and 6a in that the deflector 37 is attached to the side of the splined hub 31f oriented towards the side of the central hub 50 of the second wet clutch E2. The deflector 37 is provided with an internal skirt 371 attached to bosses 313 arranged on the splined hub 31f. The inner skirt 371 has a central bore 372 which partly forms the oil supply lines 34.

As before, the assembled disc holder 30 comprises an oil retention cavity 33 formed by the combination of surfaces coming from the splined hub 31f, from the disc support 32f and from the deflector 37. Advantageously, the retention cavity Oil 33 is formed from an outer surface of splined hub 31f, a sidewall of baffle 37, and an inner surface 38 of disc carrier 32f.

The oil retention cavity 33 is supplied with cooling fluid by a plurality of oil supply pipes 34 distributed angularly around the axis X. Each of the oil supply pipes 34 forms an elbow with a axially extending conduit portion 36 and a radially extending conduit portion 35. In this sixth embodiment, the radially 35 and axially extending conduit portions 36 are formed by combining the surfaces of the splined hub 31f and the deflector 37.

The disc support 32f is welded to the splined hub 31f while the deflector 37 rests axially on the bosses 313 provided on the splined hub 31f. The bosses 313 are distributed around the cylindrical base of the splined hub 31f. The entry of each of the oil supply lines 34 is between each boss 313.

It is understood on reading the foregoing that the present invention proposes a triple wet clutch in which the clutches are concentric and arranged radially in the same plane. The axial size of such a triple wet clutch within a torque transmission chain is reduced. This triple wet clutch features an assembled disc carrier in which the oil supply line network is simpler to design and takes less time to manufacture.

The invention cannot however be limited to the means and configurations described and illustrated here, and it also extends to any equivalent means or configuration and to any technical combination operating such means. In particular, the shape of the assembled disc holder can be modified without harming the invention, insofar as these components, ultimately, fulfill the same functions as those described in this document.

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

Claims (16)

Assembled disc carrier (30) for wet clutch comprising:
- a splined hub (31a, 31b, 31c, 31d, 31e, 31f, 31g) of axis of rotation (X) provided with an internal spline (310) for transmitting torque,
- a disc support (32a, 32b, 32c, 32d, 32e, 32f, 32g) in sheet metal with the shape of revolution around the axis (X), provided with an external groove (320) arranged to cooperate with a set multi-disc, the disk support (32a, 32b, 32c, 32d, 32e, 32f, 32g) resting axially on the splined hub (31a, 31b, 31c, 31d, 31e, 31f, 31g),
- at least one oil supply line (34),
- an oil retention cavity (33), annular and concentric with the axis (X), formed at least by the combination of surfaces coming from the splined hub and from the disc support, the splined hub partially or totally forming the 'at least one oil supply line (34) opening into the oil retention cavity (33) closed by the internal surface (38) of the disc carrier. Assembled disk carrier (30) according to claim 1 in which the disk carrier (32a, 32b, 32c, 32d, 32e, 32f, 32g) comprises orifices (39) formed on the external spline (320) and arranged to evacuate the oil contained in the oil retention cavity (33), the orifices (39) being distributed circumferentially around the axis (X) and formed on the tips of the teeth of the external spline (320). A disc carrier assembly (30) as claimed in claim 1 or 2, wherein the oil supply line (34) forms an elbow with an axially extending line portion (36) and an axially extending line portion radially (35). A disc carrier assembly (30) according to claim 3, wherein the radially extending conduit portion (35) is formed by drilling the splined hub (31a, 31d) and the axially extending conduit portion (36) is obtained directly from shape in the splined hub (31a, 31d) by casting or forging. Disc carrier assembly (30) according to the preceding claim, in which the oil retention cavity (33) is formed in part by a circumferential groove made on the outer periphery of the splined hub (31a). A disc carrier assembly (30) according to claim 3, wherein the radially (35) and axially (36) extending conduit portions are formed by mating the surfaces of the splined hub (31b) and the disc carrier (32b) . A disc carrier assembly (30) according to claim 3, wherein the radially extending duct portion (35) is formed by joining the surfaces of the splined hub (31c) and disc carrier (32c) and the duct portion axially extending (36) is formed only by the disk carrier (32c), for example by means of a hole passing through the disk carrier. Assembled disc carrier (30) according to claim 1 or 2 comprising an annular deflector (37) attached to the splined hub (31d, 31e, 31f) and comprising external toothing (373) cooperating with the profile of the internal surface (38) of the disc support (32d, 32e, 32f), the oil retention cavity (33) being formed by the combination of surfaces coming from the splined hub (31d, 31e, 31f), the disc support ( 32d, 32e, 32f) and the deflector (37). A disc carrier assembly (30) according to claim 8, wherein the oil supply line (34) forms a bend with an axially extending line portion (36) formed only by the splined hub (31e) and a radially extending duct part (35) formed by joining the surfaces of the splined hub (31e) and the deflector (37), for example a groove (351) formed in the splined hub (31e) cooperating with a side of the deflector (37). A disc carrier assembly (30) according to claim 8, wherein the oil supply line (34) forms a bend with an axially extending line portion (36) formed by mating surfaces of the splined hub (31f ) and the deflector (37) and a radially extending conduit part (35) formed by joining the surfaces of the splined hub (31f) and the deflector (37), for example a groove (351) formed in the splined hub ( 31f) cooperating with a side of the deflector (37). Wet clutch (E2) for torque transmission system comprising:
- a torque input disc carrier (10) arranged to be connected in rotation with a drive shaft along an axis of rotation (X);
- a multi-disc assembly comprising friction discs (12, 22) and pressure plates (11, 21) stacked axially and driven in rotation by the torque input disc holder (10);
- an assembled disc carrier (30) according to any one of the preceding claims arranged radially inside the multi-disc assembly and arranged to be connected in rotation to a driven shaft. Wet clutch (E2) according to the preceding claim comprising a central hub (50) with an axis of rotation (X), said central hub (50) comprising:
a cylindrical portion (52),
a flange (53) extending radially from the cylindrical portion (52) fixedly connected to the torque input disc holder (10),
and at least one cooling oil supply channel (54d) formed in the central hub (50) passing through at least the cylindrical portion (52) and emerging axially facing the oil supply pipe (34) of the assembled disc carrier (30) so that oil from the central hub can be transferred into the splined hub of the assembled disc carrier (30) and emerge in the multi-disc assembly. Wet clutch (E2) according to the preceding claim, in which the central hub (50) comprises several cooling oil supply channels (54d) and the assembled disc carrier (30) comprises several oil supply lines (34) distributed angularly around the axis (X), the outlets of the cooling oil supply channels (54d) being arranged over a diameter substantially equal to the implantation diameter of the inlets of the supply lines of oil (34). Double wet clutch (E1, E2) for torque transmission system including:
- a first clutch (E1); And
- a second clutch (E2) of the wet clutch type according to claim 12 or 13, arranged radially inside the first clutch (E1), the first and second clutches (E1, E2) being controlled to selectively couple a shaft leading to a first driven shaft and to a second driven shaft, for example first and second gearbox shafts (A1, A2), and the central hub (50) of the second clutch (E2) being common with the first clutch (E1) . Double wet clutch (E1, E2) according to the preceding claim, in which the central hub (50) comprises:
- a flange (53) extending radially beyond the second clutch (E2),
- a first annular cavity (56) arranged on the side of the flange and arranged to receive an actuating piston (15) of the first clutch (E1), and
- a second annular cavity (55) arranged on the same side of the flange as the first annular cavity (56) and arranged to receive an actuating piston (25) of the second clutch (E2),
- at least one oil pipe (54a, 54b, 54c) formed in the central hub (50) passing through the cylindrical portion (52) and opening into one of the annular cavities (55, 56), said oil pipe (54a, 54b, 54c) being separate from the cooling oil supply channel (54d) of the multi-disc assembly of the second clutch (E2). Triple wet clutch for a torque transmission system comprising a torque cut-off clutch (K0) of the multi-plate type, controlled to selectively couple a shaft driving an electric machine, and a double wet clutch (E1, E2) according to claim 14 or 15, the torque cut-off clutch (K0) being arranged radially beyond the double wet clutch (E1, E2).