CN110541908A

CN110541908A - Torque transmission device for a motor vehicle

Info

Publication number: CN110541908A
Application number: CN201910449981.0A
Authority: CN
Inventors: G.勒巴斯; E.康迈因; T.拉福热; M.索伊兰特
Original assignee: Valeo Embrayages SAS
Current assignee: Valeo Embrayages SAS
Priority date: 2018-05-28
Filing date: 2019-05-28
Publication date: 2019-12-06
Also published as: FR3081527A1; JP2019207029A; FR3081527B1

Abstract

The invention relates to a torque transmission device (11) for a motor vehicle, comprising: a first element (24) and a second element (20) which are movable in rotation about an axis (X), are coaxial and are able to transmit a torque; at least one elastic member mounted between the first element (24) and the second element (20) and resisting rotation of the first element (24) and the second element (20) relative to each other; the first element comprising a guide washer (24), the second element comprising a hub (20), the elastic member being at least partially housed in a volume delimited by the guide washer (24); characterized in that said first element comprises at least one inertia member (33) fixed to at least one of said guide washers (24).

Description

Torque transmission device for a motor vehicle

Technical Field

The present invention relates to a torque transmitting device for a motor vehicle.

Background

In such applications, the torque transmitting devices may include a friction clutch that is capable of selectively connecting the heat engine to the transmission to filter vibrations due to the non-periodicity (aperiodicity) of the engine.

the torque transmission device may in particular be equipped with a motor vehicle of the hybrid type, in which an electric machine is arranged in the drive train between the engine and the gearbox. Of course, the invention is not limited to hybrid vehicles.

fig. 1 shows a transmission assembly for a hybrid vehicle according to the prior art. Such an assembly is known in particular from document EP 3121482. The assembly comprises a heat engine 1, which heat engine 1 comprises a crankshaft 2, which crankshaft 2 can be coupled to an input shaft 3 of a gearbox 4 via a first friction clutch 5, a torsional damping device 6 and a second friction clutch 7. The damping device 6 generally comprises two elements which are rotationally coupled by an elastic member which resists the rotation of one element with respect to the other.

The transmission assembly further comprises an electric machine 8, the electric machine 8 comprising a stator 9 and a rotor 10. The rotor 10 can be coupled to the input shaft 3 of the gearbox 4 via a second friction clutch 7. The rotor 10 is also coupled to the torsional damping device 6.

The different elements of the first clutch 5, which are rotationally coupled to the crankshaft 2 when the first clutch 5 is disengaged, form a so-called upstream assembly. The different elements of the torsional damping device 6, which are coupled here to the rotor 10 of the electric machine 8 when the first clutch 5 is disengaged, and of the first clutch 5 form what is known as a downstream assembly.

In operation, in the case of such a hybrid vehicle, the heat engine 1 of the vehicle may be stopped during a driving phase of the vehicle. In such an operating phase, the rotational speed of the rotor 10 of the electric machine 8 is correlated with the rotational speed of the wheels and the first clutch is disengaged.

In case of restarting the heat engine 1, it is important to synchronize the rotational speed of the heat engine and the rotational speed of the rotor 10 before engaging the first clutch 5. It should be noted that the lower the inertia of the upstream components, the faster the rotational speed of the crankshaft 2 of the heat engine 1 can be synchronized with the rotational speed of the rotor 10.

furthermore, in order to obtain sufficient vibration damping, in particular after synchronizing and engaging the first clutch 5, a strong inertia must be maintained upstream of the torsional damping device 6.

Disclosure of Invention

The present invention is intended to respond to these various technical limitations.

To this end, the invention relates to a torsional damping device for a motor vehicle, comprising:

A first element and a second element, rotationally movable about an axis, coaxial and capable of transmitting torque,

At least one elastic member mounted between the first and second elements and resisting rotation of the first and second elements relative to each other,

The first element comprises a guide washer and the second element comprises a hub, the elastic member being at least partially housed in a volume delimited by the guide washer,

characterized in that the first element comprises at least one inertia member fixed to at least one of the guide washers.

The transmission may form a torsional damping device, which may or may not be integrated into an assembly comprising a friction clutch.

in all cases, the addition of a separate inertia member on the guide washer makes it possible to purposefully and precisely increase the inertia in the portion located upstream of the elastic member of the device.

In the case of such a transmission located downstream of the friction clutch, it is then possible to reduce the inertia of the components upstream of the clutch, in particular of the pressure plate and/or reaction plate of the clutch, while maintaining a large inertia between the elastic members of the clutch and of the transmission.

The inertial member may be an annular washer.

As a variant, the device may comprise a plurality of inertial members distributed over the periphery, each inertial member extending circumferentially over an angular sector.

The inertia member may thus form a sectorized inertia washer, for example consisting of three angular sectors.

Each inertia member may include a circumferentially extending radially outer peripheral zone from which at least one securing lug extends radially inwardly.

This structure makes it possible to increase the inertia generated by the mass of the inertia member.

The first element may comprise a friction disc coupled with the guide washer, the friction disc comprising a support on which the friction lining is mounted, the support being fixed to the guide washer directly or via an inertia member.

The radially inner periphery of the support may be fixed to said lugs of the inertia member at first fixing regions of the fixing lugs, the fixing lugs of the inertia member being fixed to at least one of the guide washers at second fixing regions of said lugs.

The first fixing region may be located radially outward of the second fixing region.

In particular, the second fixing region may be located radially inside the region of the guide washer for containing a grease which allows in particular lubricating the elastic member.

The apparatus may include a sway damping device comprising a support member and a sway counterweight movably mounted on the support member.

This characteristic makes it possible to further improve the filtration quality.

The support of the oscillation damping means is for example fixed to one of the guide washers. As a variant, the support of the oscillation damping means may be fixed to the phasing member.

The device may include a pressure plate and a reaction plate movable between an engaged position and a disengaged position, the friction disk temporarily rotationally coupling the reaction plate and the pressure plate at the engaged position of the pressure plate.

The inertia of the inertia member may be in the range of 0.005 to 0.2kg.m 2.

The inertia member may be fixed to the at least one guide washer by a rivet. The support of the friction disc may be fixed to the inertia member by rivets. The inertia member and the support of the friction disc may be fixed to at least one of the guide washers by the same rivet.

As a variant, the inertia element can be fixed by joining (clinchage), that is to say by pressing the material and crimping, by welding or soldering, by gluing or by screwing.

The second element may include a hub for coupling to an input shaft of the gearbox, and an annular web coupled to the hub. The annular web may be integral with the hub or formed from a separate component. The elastic member can be supported on a web or a guide washer.

The device may comprise a rotationally movable phasing member through which a set of resilient members are arranged in series.

The damping device then has an LTD (Long stroke Damper: acronym of Long Travel Damper) type structure which allows a large angular stroke between the first element and the second element in order to obtain an effective filtering which is not periodic with respect to vibrations and rotations.

One of the guide washers may be pivotably mounted about the hub by a bearing.

The bearing may be a plain bearing formed by a ring.

The bearing may comprise a tapered portion mounted and guided for rotation about the tapered portion of the hub.

Such a conical bearing allows absorbing possible misalignment defects between the input shaft of the gearbox and the crankshaft of the engine.

drawings

The invention will be better understood and other details, features and advantages thereof will be apparent from a reading of the following description, given by way of non-limiting example with reference to the accompanying drawings, in which:

FIG. 1 is a schematic illustration of a prior art transmission assembly;

FIG. 2 is an exploded perspective view of the torque transmitting device in accordance with the first embodiment of the present invention;

FIG. 3 is a half view in axial cross-section of the device of FIG. 2;

FIG. 4 is a perspective view of the device of FIG. 2;

FIG. 5 is a view of a second embodiment of the invention corresponding to FIG. 4;

Fig. 6 is a view of a third embodiment of the invention corresponding to fig. 4.

Detailed Description

In the description and claims, the terms "outer" and "inner" and the orientations "axial" and "radial" will be used to refer to elements of the torque transmitting device, according to the definitions given in the description. Conventionally, the axis of rotation X of the torque-transmitting devices defines an "axial" orientation, a "radial" orientation meaning an orientation orthogonal to the axis of rotation X of the torque-transmitting devices directed from the inside towards the outside by pointing away from said axis, the terms "outer (outside)" and "inner (inside)" being used to define the relative position of one element with respect to the other with reference to the axis X. The elements close to the axis are said to be internal (inboard) with respect to the outer elements positioned radially at the periphery.

A torque transmitting device 11 for a motor vehicle according to a first embodiment of the present invention is shown in fig. 1 to 3. The torque-transmitting device 11 comprises an annular reaction plate 12 having an axis X, the radially outer periphery of which is connected to the radially outer periphery of a bell-shaped cover 13, the bell-shaped cover 13 being intended to be coupled in rotation to the crankshaft 2 of the heat engine 1.

the cover 13 comprises, from rear to front, an annular radial portion 14, a cylindrical portion 15 and a radially outwardly extending flange 16. The flange 16 is fixed to the reaction plate 12.

The torque transmitting device 11 further includes an annular pressure plate (not shown) and a friction disc 17 mounted axially between the reaction plate 12 and the pressure plate.

The pressure plate is translationally movable relative to the reaction plate 12 between an engaged position and a disengaged position in which the pressure plate clamps the friction disc 17 against the reaction plate 12 or releases the friction disc 17, respectively.

The pressure plate is rotationally coupled to the reaction plate 12 by means of a resilient tongue, not shown, which exerts a return force tending to return the pressure plate to the disengaged position.

As is known per se, the displacement of the pressure plate is actuated by the membrane. The control of the clutch is generally achieved by means of an engagement stop (une butte e d' embrayage) of the actuator, which cooperates with the radially inner periphery of the diaphragm. The diaphragm forms a rod that transfers the force applied by the engagement stop to the platen.

The clutch is normally open. The rest position of the diaphragm therefore corresponds to the disengaged state of the clutch. As a variant, the clutch may be of the normally closed type.

the friction disc 17 comprises an annular support 18. Friction linings 19 are fixed on both sides of the radially outer periphery of the support 18.

The damping device is mounted between the support 18 and the central hub 20. The central hub 20 comprises internal splines 21, the internal splines 21 cooperating with external splines of a shaft connected to or forming the input of the gearbox 4 of the vehicle.

The damping device includes an annular web 22 (fig. 3) which is formed integrally with the hub 20 and extends radially outwardly from the hub 20.

The damping device further comprises two guide washers 23,24 on either side of the annular web 22. The two guide washers 23,24 are fixed to each other at their radially outer peripheries. The radially inner periphery of the front guide washer 24 is pivotally mounted about the hub 20 by means of a slide bearing. The bearing is in the form of a ring 25 rotationally coupled to the radially inner periphery of the front guide washer 24, said ring 25 comprising a frustoconical inner annular surface 26 which cooperates by shape complementation with a frustoconical portion 27 of the hub 20.

Friction means, for example formed by one or more spring washers 28, are mounted between the radially inner periphery of the rear guide washer 23 and an annular support member 29 mounted around the hub 20. Thus, the friction device 28 is capable of dissipating energy through friction.

The elastic member 30 is mounted between the guide washers 23,24 and the annular web 22 by means of a phasing member 29 and is able to resist the rotation of the guide washers 23,24 with respect to the annular web 22. The elastic member 30 is, for example, a helical compression spring.

The damping device also comprises an annular support 31, the radially inner periphery of which is fixed, for example by rivets, to the phasing member or to the rear guide washer 23. The radially outer periphery of the support 31 supports the oscillating mass 32. In this embodiment, the support 31 is formed by two annular portions 31a, 31b assembled to each other. Of course, the support 31 may be formed as a single piece.

As is known per se, the oscillating mass 32 is mounted movably on the support 31, for example by means of a link (entretoise) and a roller.

The inertia member 33 is fixed to the front guide washer 24. The inertia member 33, in particular in the form of a washer, comprises an outer peripheral zone 34 from which lugs 35 extend radially inwards, in this case three lugs 35. Each lug 35 comprises a radially central zone 36, the dimension of which in the circumferential direction is reduced with respect to a base 37 and with respect to a radially inner free end 38, the base 37 being connected to the outer peripheral zone 34.

The inner end 38 of each lug 35 is fixed at the radially inner periphery of the front guide washer 24 by two rivets 39, offset from each other in the circumferential direction, passing through holes 40 of said inner end 38. Of course, as noted above, other securing means may be used.

Furthermore, the radially inner periphery of the support 18 for the friction lining 19 is fixed at the base 37 of each lug 35 by two rivets 41 circumferentially offset from each other and passing through holes 42 of the base 37 of the lug 35.

Fig. 5 shows a second embodiment which differs from the one previously described with reference to fig. 2 to 4 in that the inertia member 33 is formed by a plurality of identical elements 33a, 33b, 33c, here three, distributed over the periphery. In other words, the inertia washer 33 is here divided into a plurality of angular sectors 33a, 33b, 33 c.

Thus, each element 33a, 33b, 33c comprises an outer peripheral portion 34 extending circumferentially over an angular sector and two lug portions 35a, 35b extending from the circumferential ends of said sector 33a, 33b, 33 c.

Each lug portion 35a, 35b has the shape of half of one of the lugs 35 described above. Thus, the free end 38 of each lug portion 35a, 35b is fixed to the radially inner periphery of the front guide washer 24 by means of a rivet 39, and the support 18 is fixed to the base 37 of each lug portion 5a, 35b by means of a rivet 41.

in the embodiment of fig. 2 to 5, the radially inner end 38 of the lug 35 or lug portion 35a, 35b is located radially inside the peripheral region of the guide washer 23,24 for accommodating the grease used for lubrication of the resilient member 30. This therefore prevents grease or lubricating fluid from leaking through the hole of the guide washer for the passage of the corresponding rivet 39.

Fig. 6 shows a third embodiment in which the inertia member 33 is in the form of an inertia washer, comprising an annular peripheral portion 34 from which an anchoring zone 43 with small dimensions extends radially inwards. Each fixing region 43 has an overall triangular shape and is fixed to the radially outer periphery of the front guide washer 24 by two rivets (only the through-holes 44 for the rivets are shown in fig. 6) circumferentially offset from each other. As previously mentioned, according to a variant not shown, such inertia member 33 may be scalloped.

In this third embodiment, the radially inner periphery of the support 18 is fixed to the front guide washer 24 by means of the same fixing rivet. In other words, the rivet serves both to fix the inertia member 33 and to fix the support 18 to the front guide washer 24.

in each of these embodiments, the inertia of the inertia member 33 is in the range of 0.005 to 0.2kg.m2, for example about 0.01kg.m 2.

Claims

1. A torque transmitting device (11) for a motor vehicle, comprising:

a first element (23,24) and a second element (20,22) which are movable in rotation about an axis (X), are coaxial and are capable of transmitting torque,

At least one elastic member (30) mounted between the first and second elements (23,24, 20,22) and resisting rotation of the first and second elements (23,24, 20,22) relative to each other,

The first element comprising a guide washer (23,24), the second element comprising a hub (20), the elastic member (30) being at least partially housed in a volume delimited by the guide washer (23,24),

Characterized in that said first element comprises at least one inertia member (33) fixed to at least one of said guide washers (23, 24).

2. The device (11) according to claim 1, wherein said inertial member is an annular washer (33).

3. Device (11) according to claim 1, characterized in that it comprises a plurality of inertia members (33a, 33b) distributed over the circumference and each extending circumferentially over an angular sector.

4. Device (11) according to any one of claims 1 to 3, characterized in that each inertia member (33) comprises a radially outer peripheral zone (34) extending circumferentially, from which at least one securing lug (35,43) extends radially inwards.

5. device (11) according to any one of claims 1 to 4, characterized in that said first element comprises a friction disc (17) coupled with said guide washers (23,24), said friction disc comprising a support (18) on which a friction lining (19) is mounted, said support (18) being fixed to said guide washers (23,24) directly or through said inertia member (33).

6. Device (11) according to claims 4 and 5, characterized in that the radially inner periphery of said support (18) is fixed to said fixing lug (35) of said inertia member at a first fixing region (37) of said lug (35), the fixing lug (35) of said inertia member (33) being fixed to at least one of said guide washers (23,24) at a second fixing region (38) of said lug (35).

7. Device (11) according to claim 6, characterized in that said first fixing area (37) is located radially outside said second fixing area (38).

8. The device (11) according to any one of claims 1 to 7, characterized in that it comprises oscillation damping means comprising a support (31) and an oscillating weight (32) movably mounted on said support (31).

9. the device (11) according to any one of claims 1 to 8 and claim 5, characterized in that it comprises a pressure plate and a reaction plate (12) movable between an engaged position and a disengaged position, in the engaged position of which the friction disc (17) can temporarily rotationally couple the reaction plate (12) with the pressure plate.

10. The device (11) according to any one of claims 1 to 9, wherein the inertia of the inertia member (33) is in the range of 0.005 to 0.2kg.m 2.