WO2016110646A1

WO2016110646A1 - Torque transmission device with elastic blade equipped with a centrifugal-mass torsion damper

Info

Publication number: WO2016110646A1
Application number: PCT/FR2016/050016
Authority: WO
Inventors: Jérôme BOULET; Daniel Fenioux
Original assignee: Valeo Embrayages
Priority date: 2015-01-07
Filing date: 2016-01-06
Publication date: 2016-07-14
Also published as: FR3031367B1; FR3031367A1

Abstract

The invention relates to a torque transmission device (1) for a motor vehicle drive train, comprising: - a torque input element (2) and a torque output element (3) which are capable of rotating one with respect to the other about an axis of rotation X; - elastic damping means comprising at least one elastic blade (14, 15) coupling the input element (2) and the output element (3) in such a way as to allow a transmission of torque with damping of vibrations between the input element (2) and the output element (3); and - a centrifugal-mass torsion damper (35) comprising at least one inertial mass (21) mounted to oscillate in rotation on a support (13) that rotates as one with either the input or output element (2, 3).

Description

ELASTIC BLADE TORQUE TRANSMISSION DEVICE EQUIPPED WITH CENTRIFUGAL MASS TORSION DAMPER

Technical area

The invention relates to the field of transmissions for a motor vehicle and relates more particularly to a torque transmission device, such as a double damping flywheel, capable of filtering motor acyclisms.

Technological background

An explosion engine has, because of successive explosions in the cylinders of the engine, acyclisms whose frequency varies in particular according to the number of cylinders and the speed of rotation of the engine.

In order to filter the vibrations generated by the acyclisms upstream of the gearbox, it is known to equip the vehicle transmissions with a torque transmission device comprising means for damping vibrations, such as a double steering wheel. damper (DVA). Otherwise, vibrations entering the gearbox would cause in operation shocks, noises or noise particularly undesirable.

The double damping flywheels comprise a primary flywheel and a coaxial secondary flywheel, mobile in rotation relative to each other. The primary flywheel is intended to be attached to the crankshaft of a combustion engine. The secondary flywheel forms a reaction plate for cooperating with a clutch disc. The primary and secondary flywheels are coupled in rotation by resilient deformable members for transmitting torque and damping rotational acyclisms. The resilient deformable members are generally helical springs circumferentially disposed in an annular chamber which is formed in the primary flywheel. The coil springs are, on the one hand, in abutment against bearing zones carried by the primary flywheel, and, on the other hand, in support against radial tabs of an annular web which is fixed by rivets to the steering wheel. secondary. Thus, any rotation of one of said flywheels relative to the other causes compression of the springs which exerts a restoring force adapted to return said flywheels to a relative angular position of rest. Such a double damping flywheel is for example described in document FR2936290. In order to reduce the fuel consumption of combustion engines, the number of cylinders of the engines tends to decrease. However, the decrease in the number of cylinders is accompanied by an increase in the amplitude of the acyclisms.

Moreover, in order to improve driving comfort, in particular by avoiding noise or noise particularly undesirable, it is constantly sought to increase the filtration performance of vibration dampers.

Therefore, in view of the aforementioned developments, damping dual flywheels of the prior art are not fully satisfactory.

summary

The invention aims to remedy these problems by proposing a torque transmission device for effectively filtering vibrations.

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

- a torque input member and a torque output member movable in rotation relative to each other about an axis of rotation X;

resilient damping means coupling the input element and the output element so as to allow torque transmission with damping of the vibrations between the input element and the output element, this transmission of torque with damping being accompanied by a relative rotation between the input member and the output member; the elastic damping means comprising at least one resilient blade integral in rotation with one of the input and output elements and cooperating with a support element carried by the other of said input and output elements; the elastic blade being arranged such that, in a relative angular position between the input element and the output element different from a relative rest position, the support element exerts a bending force on the an elastic blade producing an opposite reaction force of the elastic blade on the support element, this reaction force having a circumferential component able to return said input and output elements towards said relative position of rest; and

a centrifugal mass torsion damper comprising at least one mass inertia device rotatably mounted in rotation on a support integral in rotation with one of the input and output elements.

Thus, such a torque transmission device combines resilient elastic blade damping means with a centrifugal mass torsion damper which provides filtration performance particularly advantageous acyclisms.

According to other advantageous embodiments, such a torque transmission device may have one or more of the following characteristics:

the or each mass of inertia is able to oscillate relative to the support of the centrifugal mass torsion damper in a plane orthogonal to the axis of rotation X in response to the irregularities of rotation of said support.

the resilient blade has a cam surface and the support member has a cam follower arranged to cooperate with the cam surface.

- The cam follower is a roller rotatably mounted on said input or output element, for example by means of a rolling bearing. the support element is arranged radially outside the elastic blade. Such an arrangement makes it possible to retain the elastic blade radially when it is subjected to centrifugal force.

the elastic blade is arranged to deform in a plane perpendicular to the axis of rotation X.

the cam surface extends over an angular opening greater than 30 °, in particular greater than 45 ° or 60 °, for example greater than 90 °.

the cam surface has, when observed along the axis of rotation X, a substantially concave shape, this concavity being on the side of the axis of rotation.

the support of the centrifugal mass torsion damper is rotatably connected to the output element. Thus, the centrifugal mass torsion damper is all the more effective if it is disposed at the outlet of one or more damping stages, and as a result, it is subjected to a level of torsional excitations less important, which prevents it from saturating. the elastic damping means comprise an attachment portion which is connected to the elastic blade and which is fixed on said input or output member so as to rotate said resilient blade to said input or output element.

the fixing part is fixed to the input or output element by means of fasteners, for example rivets.

the fixing part and the elastic blade of the elastic damping means can be formed in one piece.

the fixing part of the elastic damping means is advantageously fixed on the output element.

according to one embodiment, the attachment portion of the elastic damping means further forms the support on which said at least one mass of inertia is mounted oscillatingly. Thus, the function of elastic coupling between the input and output elements and the support function of the mass (s) of inertia of the centrifugal mass torsion damper are made by the same element.

according to one embodiment, the resilient damping means comprise a plurality of resilient blades each cooperating with a support member and the fixing portion is an annular body connected to the plurality of resilient blades.

the annular body may be integral and the annular body and the elastic blades formed integrally.

according to another embodiment, the elastic damping means comprise a plurality of resilient blades which each cooperate with a support element and the fixing part comprises a plurality of separate fastening elements which are each connected to an elastic blade respective and independently attached to said input or output element. When the fixing portion has a plurality of separate fastening elements and the centrifugal mass torsion damper has a plurality of inertia masses, it is possible to distribute the masses of inertia on the fastening elements of such so that each of the fasteners form a support for at least one of said mass of inertia. when the elastic damping means comprise an even number of resilient blades, two for example, the blades of each pair are symmetrical with respect to the axis of rotation X which contributes to the balance of the torque transmission device.

in a particular embodiment, the elastic blade may comprise an inner strand, an outer strand and a bent portion connecting the inner strand and the outer strand.

according to one embodiment, the or each mass of inertia comprises two flanks extending axially on either side of the attachment portion of the elastic damping means, the two flanks being connected to one another via connecting struts which pass through an opening in said fastening portion.

According to one embodiment, each connecting strut passes through an associated opening formed in the fixing portion. However, in another embodiment, it is also possible to provide for two or more connecting struts to pass through the same opening in the fastening portion.

advantageously, the input or output element to which is secured in rotation the fixing portion of the resilient damping means comprises a plurality of attachment zones through which pass the fasteners, the fixing part being plated axially against said attachment areas of said attachment portion, said fixing areas projecting axially towards the other of said input or output elements so that two circumferentially consecutive attachment areas are separated by a recess in which is housed at least partially one of the two flanks. Such an arrangement makes it possible to further limit the size.

according to one embodiment, the attachment portion of the elastic damping means has an axial recess accommodating at least partially a sidewall of at least one mass of inertia. In other words, the fastening portion has a smaller axial dimension at the deflection region of the or each mass of inertia so as to allow a reduction in axial size. according to a first type of torque transmission device, the centrifugal mass torsion damper is a pendulum damper comprising a plurality of masses of inertia evenly distributed over the fastening portion of the elastic damping means.

- In the case of a pendular damper, the device comprises means for guiding the masses of inertia which comprise, for each mass of inertia, two rolling members which each cooperate with a first raceway carried by said mass of inertia and with a second runway carried by the fixing portion of the elastic damping means.

each first rolling track is formed on one of the connecting struts and each second running track is formed by an outer edge of one of the passage openings of a connecting strut formed in the fixing part of the means. damping elastics.

according to a second type of torque transmission device, the centrifugal mass torsion damper is an inertial drummer and the mass of inertia is rotatably coupled to the attachment portion of the elastic damping means via a plurality of elastic return members adapted to generate a force for returning the mass of inertia relative to the fixing portion in a relative position of equilibrium.

By way of example, the moment of inertia of the centrifugal mass and the stiffness of all the elastic members are such that the centrifugal mass has a resonance frequency of between 12 Hz and 60 Hz, and preferably of 6 nm. at 9n Hz for an engine having n cylinders. Such a resonance frequency can in particular be used to filter the vibrations that appear around 1000 revolutions / min.

according to one embodiment, the elastic return members comprise a plurality of lamellae which are each formed in the fastening portion, inside one of the passage openings of a connecting spacer, and each cooperate with said connecting strut. The elastic strips can in particular be formed in one piece with the fixing portion. In this case, the elastic strips are obtained during the cutting of the passage openings of the connecting struts in the fixing part. the torque transmission device may further comprise a friction assembly arranged to exert a friction resisting torque between the input element and the output element during a relative rotation between the input element and the output element.

according to an advantageous embodiment, the friction assembly extends radially outside the at least one mass of inertia of the torsion damper with centrifugal mass, which makes it possible to limit the axial space requirement of the combination of the friction assembly and the centrifugal mass torsion damper.

- The friction assembly comprises a friction washer and a spring washer adapted to exert a force in an axial direction towards the input member so as to press the first friction washer against the input element. The attachment portion of the elastic damping means is fixed to the output member and has a lug housed in a groove of the friction washer so as to rotate said friction washer relative to the input member. during a relative rotation between the input element and the output element.

the tab of the fixing portion extends radially outwards.

the torque transmission device is for example a double damping flywheel. In other words, the input element is a primary flywheel intended to be fixed at the end of a crankshaft and the output element is a secondary flywheel which is intended to form a reaction plate for a clutch device. the centrifugal mass torsion damper is housed axially between the primary flywheel and the secondary flywheel of the double damping flywheel.

- The elastic damping means are housed axially between the input element and between the output element, that is to say between the primary flywheel and the secondary flywheel when the torque transmission device is a double damper steering wheel.

According to one embodiment, the invention also provides a motor vehicle comprising a torque transmission device mentioned above.

Brief description of the figures The invention will be better understood, and other objects, details, characteristics and advantages thereof will appear more clearly in the course of the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes. with reference to the accompanying drawings.

FIG. 1 is a partial view of a double damping flywheel according to a first embodiment, in which the secondary flywheel is not shown in order to allow visualization of the elastic damping means with elastic blades and the damper. pendulum.

- Figure 2 is a sectional view of the double damping flywheel of Figure 1 according to the plane ll-ll.

FIG. 3 is a detailed perspective view of the elastic damping means with elastic blades and of the swinging damper of the double damping flywheel of FIG. 1.

- Figure 4 is a partial front view of a double damping flywheel according to a second embodiment in which the primary flywheel is not shown.

- Figure 5 is a partial exploded view of the double damping flywheel of Figure 4 partially illustrating the resilient damping means and the pendulum damper.

- Figure 6 is a sectional view of a double damping flywheel according to a third embodiment comprising elastic damping means with elastic blades and an inertial drummer.

- Figure 7 is a partial view of the double damping flywheel of Figure 6 illustrating in detail the fixing portion of the elastic damping means with elastic blades forming a support for the mass of inertia of the inertial drummer.

- Figure 8 is a sectional view along a radial plane of the attachment portion of the resilient elastic damping means and the inertial drummer of Figure 7.

- Figure 9 is a sectional view along the plane IX-IX of elastic damping means with elastic blades and the inertial drummer of Figure 8. FIG. 10 is a graph illustrating the amplitude of the accelerations representative of the acyclisms at the input of the gearbox as a function of the engine speed, for transmission chains equipped with different damping double flywheels.

Detailed description of embodiments

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

In relation to FIG. 2, a double damping flywheel 1 comprising a primary flywheel 2 intended to be fixed at the end of a crankshaft of an internal combustion engine, not shown, and a steering wheel secondary inertia 3 which is centered and guided on the primary flywheel 2 by means of a bearing 4, such as a rolling bearing ball. The secondary flywheel 3 is intended to form the reaction plate of a clutch, not shown, connected to the input shaft of a gearbox. The primary and secondary flywheels 3 are intended to be mounted movably about an axis of rotation X and are, moreover, rotatable relative to each other about said axis X.

The primary flywheel 2 comprises a radially inner hub 5 supporting the bearing 4, an annular portion 6 extending radially from the hub 5 and a cylindrical portion 7 extending axially rearwardly from the periphery external of the annular portion 6. The primary flywheel 2 is provided with orifices for the passage of fastening screws 8, for fixing the primary flywheel 2 on the crankshaft of the engine. The primary flywheel 2 carries, on its outer periphery, a ring gear 9 for driving in rotation of the primary flywheel 2, using a starter.

The secondary flywheel 3 comprises a flat annular surface 10, turned towards the rear, intended to form a bearing surface for a friction lining of a clutch disk, not shown. In other words, the secondary flywheel 3 is intended to form a reaction plate of a clutch device. The secondary flywheel 3 has, near its outer edge, studs 1 1 and orifices, not shown, for mounting a cover of the clutch device. The secondary flywheel 3 further comprises orifices 12, arranged vis-à-vis the orifices formed in the primary flywheel 2, and for the passage of the fastening screws 8, when mounting the double damping flywheel 1 on the crankshaft.

In relation with FIG. 1, resilient damping means are observed coupling the primary flywheel 2 and the secondary flywheel 3 so as to allow transmission of the vibration damping torque between the primary and secondary flywheels 3. damping elastics comprise an attachment portion which is here formed of a central body 13 and two elastic blades 14, 15 curved around the X axis and developing from the central body 13. The central body 13 is integral and of annular form. The central body 13 and the resilient blades 14, 15 are integrally formed. The two resilient blades 14, 15 are symmetrical to each other with respect to the axis of rotation X.

As shown in the lower part of FIG. 2, the central body 13 is fixed on the secondary flywheel 3. To do this, the central body 13 is provided with a plurality of circumferentially distributed orifices 16 allowing the passage of rivets 17 passing through. in addition through orifices of the secondary flywheel 3. The central body 13 of the elastic damping means has an annular shape and is thus fitted on a skirt 18 of axial orientation 18 of the secondary flywheel 3 so as to ensure a centering of the elastic damping means relative to the secondary flywheel 3. The central body 13 is sandwiched axially between a head of the rivet 17 and an attachment zone 19 of the secondary flywheel 3. The attachment zones 19 protrude axially towards the primary flywheel 2. Thus, between two circumferentially consecutive fastening zones 19 , a recess 20 is formed in the secondary flywheel 3. This recess 20 illustrated on the upper part of Figure 2, can partially accommodate a mass of inertia 21 of a torsion damper centrifugal mass 35 which will be described so detailed thereafter.

Returning to FIG. 1, it can be seen that each elastic blade 14, 15 has a cam surface which is arranged to cooperate with a support element formed by a cam follower 22 carried by the primary flywheel 2. The cam followers 22 are here rollers 23 mounted rotatably on the primary flywheel 2. The cam followers 22 are held in abutment against their respective cam surface and are arranged to roll against said cam surface during a relative movement between the flywheels In addition, the cam followers 22 are radially disposed outside their respective cam surfaces so as to radially maintain the resilient blades 14, 15 when subjected to centrifugal force.

Each cam surface is arranged such that, for a relative rotation between the primary flywheel 2 and the secondary flywheel 3 in one direction or the other, relative to a relative angular position of rest, the cam follower 22 is moves on the cam surface and, in doing so, exerts a bending force on the resilient blade 14, 15. By reaction, the elastic blade 14, 15 exerts on the cam follower 22 a restoring force having a circumferential component which tends to return the primary flywheels 2 and secondary 3 to their relative angular position of rest. Thus, the resilient blades 14, 15 are capable of transmitting a driving torque from the primary flywheel 2 to the secondary flywheel 3 (forward direction) and a resistant torque of the secondary flywheel 3 to the primary flywheel 2 (retro direction). Moreover, the torsional vibrations and the irregularities of torque which are produced by the motor and transmitted by the crankshaft to the primary flywheel 2 are damped by the flexion of the elastic blades 14, 15.

In order to reduce the parasitic friction that may affect the damping function, the rollers 23 are advantageously rotatably mounted on the primary flywheel 2 by means of rolling elements 24, such as balls, rollers or rods. needles. In the embodiment shown on the 2, the rollers 23 are each carried by a cylindrical rod 25 extending parallel to the axis of rotation X and one end of which is fixed inside a bore 26 formed in the primary flywheel 2. Moreover, the cylindrical rod 25 is received inside a through-orifice formed in a sleeve 27. The cylindrical rod 25 comprises forwardly a head 28 which rests against a countersink formed in the rear face of the sleeve 27.

The roller 23 is rotatably mounted around the sleeve 27. To do this, the rolling members 24 cooperate, on the one hand, with a rolling track formed on the outer periphery of the sleeve 27 and, on the other hand, with a running track formed on the inner periphery of the roller 23. The rolling members are retained axially and protected, forwards, by a protective washer 29 fitted on the sleeve 27 and, aft, by a shoulder 30 formed at the rear end of the sleeve 27.

The sleeve 27 also carries a seat ring 31 which is mounted tightly around the sleeve 27. The seat ring 31 is axially bearing against the primary flywheel 2. In addition, the seat ring 31 cooperates with a surface of external retaining formed in the cylindrical portion 7 of the primary flywheel 2. The radial forces supported by the cam followers 22 are thus taken up by the primary flywheel 2 on a large axial dimension which limits the risk of deformation of the cylindrical rod 25.

The double damping flywheel is also equipped with a friction assembly, represented in FIG. 2, arranged to exert a friction-resistant torque during the relative rotation between the primary and secondary flywheels 3. The friction assembly is thus suitable. to dissipate the energy accumulated in the resilient blades 14, 15. The friction assembly comprises a friction washer 32 and a spring washer 33 of Belleville type which is wedged axially backwards by a circlip 34. The spring washer 33 exerts an axial force directed forward on the friction washer 32 so as to press against the primary flywheel 2. The circlip 34 is retained in a fixing groove formed on the inner periphery of the cylindrical portion 7 of the primary flywheel 2 The friction assembly is disposed radially outside the centrifugal mass torsion damper 35 which makes it possible to limit the axial space requirement of the double flight shock absorber 1. As shown in Figure 1, the central body 13 is provided with two diametrically opposed lugs 36 which are directed radially outwardly and slightly bent forwardly. Each of the tabs 36 is housed in a groove 37 formed in the inner periphery of the friction washer 32. Thus, the friction washer 37 can be rotated by the tabs 36 so that during a relative rotation between the primary flywheel 2 and secondary 3, the friction washer 37 moves relative to the primary flywheel 2 and thus exerts a friction torque opposing the relative rotation of the primary flywheels 2 and secondary 3.

Moreover, with reference to FIGS. 2 and 3, it can be seen that the double damping flywheel 1 is also equipped with a centrifugal mass torsion damper 35 of the pendulum damping type. The pendulum damper comprises a plurality of masses of inertia 21, also called pendulum weights, circumferentially distributed on a support. The support is here directly formed by the central body 13 of the elastic damping means. The pendulum weights 21 are able to oscillate with respect to the central body 13 in a plane orthogonal to the axis of rotation X, in response to the irregularities of rotation.

The pendulum weights 21 have a general shape of an arc of a circle. Each pendulum weight 21 comprises two sidewalls 38, 39 which are arranged on either side of the central body 13 and are connected axially to one another by means of two connecting struts 40. To this end, each flank 38, 39 has two cuts for mounting by force-fitting connecting struts 40. Furthermore, each connecting strut 40 axially passes through an opening in the central body 13.

Oscillations pendulum 21 are guided by guide means. The guide means comprise, for each counterweight 21, two rolling elements 41 which each cooperate with a first rolling track carried by the pendulum 21 and with a second rolling track, carried by the central body 13. For each element 41, the first and second raceways are arranged radially facing each other.

In relation to the upper part of FIG. 2, it is observed that the first raceways are carried by the connecting spacer 40 connecting the flanks 38, 39 of each counterweight 21 and that the second race tracks are formed by the outer edge of the passage openings of the connecting struts 40. The rolling element 41 is, for example, formed by a cylindrical roller section circular. The first and second race tracks have a generally epicyclic or circular shape. The shapes of the rolling tracks are arranged in such a way that the pendulum weights 21 are tuned to an order taking a value close to the rank of the predominant harmonic vibrations generated by the engine. A motor operating with 2n cylinders generating primarily harmonic rank n the pendulum damper must be granted to an order taking a value close to n to dampen the main vibrations.

The pendulum weights 21 and / or the central body 13 may comprise abutment elements of elastomeric material for damping shocks, when the pendulum weights 21 arrive at the end of stroke or during engine stop. According to one embodiment, the heads of the rivets 17 may be covered with elastomeric material so as to form end stops.

In relation with FIG. 1, it can be seen that each pendulum weight 21 is disposed circumferentially between two orifices 16 formed in the central body 13 and allowing the fastening rivets 17 of the central body 13 to pass over the secondary flywheel 3. Thus, as shown in the upper part of Figure 2, the rear flank 38 of each counterweight 21 is housed in a recess 20 of the secondary flywheel 3 separating two circumferentially consecutive fastening zones 19. Such an arrangement makes it possible to limit the axial size of the double damping flywheel 1 thus produced.

FIG. 10 illustrates the angular acceleration (in ordinate, expressed in rad / s ² ) of the input shaft of a gearbox representative of rotation acyclisms, as a function of the engine speed (in abscissa, expressed in revolutions / mn) for motor vehicle transmissions which are respectively equipped:

- A double damping flywheel whose elastic damping means are helical springs (Curve A);

- A double damping flywheel whose elastic damping means are elastic blades (Curve B); and

- A double damping flywheel 1 whose elastic damping means are elastic blades 14, 15 and further comprising a pendulum damper (Curve C).

It is thus found that a double damping flywheel as described above associating elastic damping means with resilient blades and a pendulum damping makes it possible to obtain vibration filtering performances that are much greater than those of the other damping double flywheels.

Figures 4 and 5 partially illustrate a double damping flywheel 101 according to a second embodiment. Elements identical or similar to the elements of Figures 1 to 3, that is to say, performing the same function, have the same reference number increased by 100.

In this embodiment, each elastic blade 1 14, 1 15 has an internal strand 142, an outer strand 144 and a bent portion 143 connecting the inner strand 142 and the outer strand 143. The bent portion 143 has an angle of about 180 ° so that a portion of the inner strand 142 is located radially between a portion of the outer strand 144 and the X axis. In other words, the elastic blade 1 14, 1 15 has two radially offset regions one on the other and separated by a radial space. Such a shape of the elastic blades 1 14, 1 15 allows them to develop over longer lengths which allows to provide a cam surface having a large circumferential length. Thus, the angular stiffness of the elastic damping means can be reduced, which leads to a significant increase in filtration performance.

Given the particular shape of the resilient blades 14, 15, the attachment portion 13 is here formed of two separate fasteners 145 of arcuate shape which are respectively formed integrally with the one and the Another of the two resilient blades 11, 1, 15. Each fastener 145 is attached to the secondary flywheel 103 independently through a plurality of rivets 11, three in the illustrated embodiment. Furthermore, each of the fastening elements 145 forms a support on which is mounted oscillating a counterweight 121.

In connection with FIG. 5, it is also observed that the fixing part

1 13 may have a recess 151, that is to say a smaller axial dimension at the deflection zone of each counterweight 201 which makes it possible to reduce the axial size of each pendulum balance 121.

In connection with Figures 6 to 9, we will now describe a double damping flywheel 201 according to a third embodiment. Elements identical or similar to the elements of Figures 1 to 3, that is to say fulfilling the same function, have the same reference number increased by 200.

The general structure of the double damping flywheel 201 is identical to the structure of that described in relation to FIGS. 1 to 3 and differs from it only in that the centrifugal force torsion damper is here an inertial drummer and not a pendulum damper. An inertial drummer selectively filters the vibrations for a specific frequency range.

It can be observed in FIGS. 7 and 8 that the inertial drummer comprises a single mass of inertia 221 which is mounted oscillating on the central body 213 of the elastic damping means. The mass of inertia 221 comprises two flanks 238, 239 which extend on either side of the central body 213 and which are connected to one another by means of a plurality of connecting struts. 240 passing through openings 246 formed in the central body 213. The connecting struts 240 are received inside cutouts 247 formed in the flanks 238, 239 and for securing the connecting struts 240 to said flanks 238, 239 , by press fitting, for example.

The front flank 239 has an annular shape. The rear flank 238 is itself composed of a plurality of arcuate elements 248 which are separated from one another at the attachment zones 219 of the central body 213 on the secondary flywheel 203. Each arcuate element 248 is connected to the sidewall. before 239 via a connecting strut 240.

As shown in the upper part of Figure 6, each arcuate element 248 of the trailing edge is housed in a recess 220 of the secondary flywheel 203 separating two fastening zones 217 of the central body 213 on the secondary flywheel 203 circumferentially consecutive. Furthermore, as shown in the lower part of FIG. 6, the front flank 239 has rivets 217 at the head for fastening the central body 213 to the secondary flywheel 213, a recess 249 in which at least part of the recess is housed. head of a rivet 217. Such an arrangement makes it possible to optimize the inertia of the mass with respect to its axial size.

Moreover, the mass of inertia 221 of the inertial beater is rotatably coupled to the central body 213 via a plurality of elastic members, illustrated in FIG. 9. The elastic members generate a restoring force which opposes the rotation of the mass of inertia 221 with respect to its equilibrium position.

The moment of inertia of the mass of inertia 221 as well as the stiffness of the set of elastic members are adjusted so that the resonant frequency of the inertial drummer corresponds to the frequency of the vibrations to be filtered. For example, the inertial drummer may have a resonance frequency between 12 Hz and 60 Hz, and preferably from 6n to 9n Hz for a motor having n cylinders.

Such a resonance frequency can in particular be used to filter the vibrations that appear around 1000 revolutions / min.

In the embodiment shown in FIG. 9, the resilient members are elastic strips 250 which are formed in the central body 213 and extend inside the openings 246 for the passage of the connecting struts 240. The elastic strips 250 are integral with the central body 213. Each opening 246 is equipped with two elastic strips 250 which are disposed on either side of the connecting spacer 240 passing through said opening 246. Thus, one of the elastic lamellae 250 makes it possible to return the mass of inertia 221 towards a position of equilibrium during a relative rotation of the mass of inertia 213 with respect to the central body 213 in a first direction of rotation while the other of the lamellae Elastics 250 makes it possible to return the mass of inertia 221 towards its position of equilibrium during a relative rotation of the mass of inertia 221 with respect to the central body 213 in a second direction of rotation.

Note, however, that other types of elastic members may be used. Thus, in another embodiment not shown, the elastic members are helical springs arranged in a circumferential orientation and having ends bearing against the mass of inertia 221 and against the central body 213. The curve D of FIG. 10 shows the angular acceleration of the input shaft of a gearbox representative of rotation acyclisms, as a function of the engine speed for a motor vehicle transmission equipped with a double damper flywheel 201 whose elastic damping means are elastic blades 214, 215 and further comprising an inertial drummer.

It can thus be seen that a double damping flywheel 201 as described above combining elastic damping means with elastic blades and an inertial beater also makes it possible to obtain excellent vibration filtration performance.

Although the invention has been described in connection with several particular embodiments, it is obvious that it is not limited thereto and that it comprises all the technical equivalents of the means described and their combinations if they are within the scope of the invention.

The use of the verb "to include", "to understand" or "to include" and its conjugated forms does not exclude the presence of other elements or steps other than those set out in a claim. The use of the indefinite article "a" or "an" for an element or a step does not exclude, unless otherwise stated, the presence of a plurality of such elements or steps.

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

Claims

1. Torque transmission device (1, 101, 201) for a motor vehicle transmission chain comprising:

- a torque input member (2, 102, 202) and a torque output member (3, 103, 203) rotatable relative to each other about an axis of rotation

X;

resilient damping means coupling the input element (2, 102, 202) and the output element (3, 103, 203) so as to allow a torque transmission with vibration damping between the element (2, 102, 202) and the output element (3, 103, 203), this torque transmission with damping being accompanied by a relative rotation between the input element (2, 102, 202). ) and the output element (3, 103, 203); the elastic damping means comprising at least one elastic blade (14, 15, 14, 15, 214, 215) integral in rotation with one of the input and output elements (2, 3, 102, 103 202, 203) and cooperating with a support element (22) carried by the other of said input and output elements (2, 3, 102, 103, 202, 203); the resilient blade (14, 15, 14, 15, 214, 215) being arranged such that in a relative angular position between the input member (2, 102, 202) and the output member (3, 103, 203) different from a relative position of rest, the support element (22) exerts a bending force on the elastic blade (14, 15, 1 14, 1 15, 214, 215) producing a counteracting force of the elastic blade (14, 15, 14, 15, 214, 215) on the bearing element (22), this reaction force having a circumferential component able to recall said elements of input and output (2, 3, 102, 103, 202, 203) to said relative rest position; and

- A centrifugal mass torsion damper (35, 135, 235) comprising at least one mass of inertia (21, 121, 221) rotatably mounted in rotation on a support (13, 1 13, 213) integral in rotation one of the input and output elements (2, 3, 102, 103, 202, 203).

2. A torque transmission device according to claim 1, wherein the support (13, 13, 213) is integral in rotation with the output element (3, 103, 203).

3. Torque transmission device according to claim 1 or 2, wherein the elastic damping means comprise a portion of fastener (13, 13, 213) which is connected to the resilient blade (14, 15, 14, 15, 214, 215) and which is attached to said input or output member (2, 3, 102) , 103, 202, 203) in such a way as to rotate said elastic blade (14, 15, 14, 1, 15, 214, 215) to said input or output element (2, 3, 102, 103, 202, 203) and wherein the fixing portion (13, 13, 213) further forms the support on which said at least one inertia mass (21, 121, 221) is oscillatingly mounted.

A torque transmission device according to claim 3, wherein the resilient damping means comprises a plurality of resilient blades (14, 15, 214, 215) which each cooperate with a support member (22) and wherein the fixing portion (13, 213) is a one-piece annular body connected to the plurality of resilient blades (14, 15, 214, 215).

A torque transmitting device according to claim 3, wherein the resilient damping means comprises a plurality of resilient blades (1, 14, 1, 15) which each cooperate with a bearing member (22) and wherein the portion fastening means (13) comprises a plurality of separate fastening elements (145) which are each connected to a respective resilient leaf (11, 15) and independently secured to said input or output member (2, 3, 102, 103, 202, 203).

Torque transmission device according to any one of claims 3 to 5, wherein the or each mass of inertia (21, 121, 221) has two flanks (38, 39, 138, 139, 238, 239). extending axially on either side of the fastening portion (13, 13, 213) of the elastic damping means, the two flanks (38, 39, 138, 139, 238, 239) being connected to each other; to one another via connecting struts (40, 140, 240) which pass through an opening in the fastening portion (13, 13, 213).

Torque transmission device according to claim 6, in which the input or output element (2, 3, 102, 103, 202, 203) to which the fixing part (13, 13) is secured in rotation. , 213) resilient damping means comprises a plurality of fastening zones (19, 1 19, 219) through which fastening members (17, 17, 217) of said fastening portion (13, 13) pass. 213), the fastening portion (13, 13, 213) being axially pressed against said attachment regions (19, 19, 219), said attachment regions (19, 19, 219) projecting axially towards the other of said input or output elements of such that two circumferentially consecutive fastening regions (19, 19, 219) are separated by a recess (20, 120, 220) in which at least one of the two flanks (38, 138, 238) is housed.

Torque transmission device according to claim 6 or 7, wherein the fastening portion (1 13) has an axial recess (151) at least partially accommodating a sidewall of at least one mass of inertia.

A torque transmission device according to any of claims 3 to 8, wherein the centrifugal mass torsion damper (35, 135) is a pendulum damper having a plurality of inertia masses (21, 121). regularly distributed on the fixing portion (13, 13).

10. A torque transmission device according to claim 9, comprising means for guiding the masses of inertia which comprise, for each mass of inertia (21, 121), two rolling members (141) which each cooperate with a first track. rolling carried by said mass of inertia (21, 121) and with a second raceway carried by the fixing portion (13, 13).

1 1. A torque transmission device according to claims 9 and 10, when claim 9 is dependent on one of claims 6 to 8, wherein each first raceway is provided on one of the connecting struts (40, 140) and wherein each second raceway is formed by an outer edge of one of the passageways of a connecting strut (40, 140) formed in the attachment portion (13, 13).

A torque transmission device according to any one of claims 3 to 8, wherein the centrifugal mass torsion damper (235) is an inertial drummer and wherein the mass of inertia (221) is rotatably coupled. to the fixing portion (213) via a plurality of resilient return members (250) adapted to generate a force for biasing the inertial mass (221) relative to the attachment portion (213) in a relative position of equilibrium.

Torque transmission device according to claim 12 when dependent on one of claims 6 to 8, wherein the spring return members comprise a plurality of lamellae (250) which are each formed in the attachment portion ( 213), inside one of the openings (246) for passing a connecting strut (240) and each cooperating with said connecting struts (240).

14. Torque transmission device according to any one of claims 1 to 13, further comprising a friction assembly arranged to exert a friction resisting torque between the input member (2, 102, 202) and the output member (3,103,203) in relative rotation between the input member and the output member.

15. A torque transmission device according to claim 14, wherein the friction assembly extends radially outside the at least one mass of inertia (21, 121, 221) of the torsion damper. with centrifugal mass (35, 135, 235).

16. A torque transmission device according to claim 15, wherein the friction assembly comprises a friction washer (32, 132, 232) and a spring washer (33, 133, 233) adapted to exert a force in one direction. axial direction to the input member (2, 102, 202) so as to press the first friction washer (32, 132, 232) against the input member and wherein the attachment portion (13, 1 13, 213) resilient damping means is attached to the output member (3, 103, 203) and includes a tab (36, 136, 236) housed in a groove (37) of the friction washer ( 32, 132, 232) for rotating said friction washer (32, 132, 232) relative to the input member (2, 102, 202) in a relative rotation between the element input (2, 102, 202) and the output element (3, 103, 203).

17. Torque transmission device according to any one of claims 1 to 16, wherein the input element is a primary flywheel (2, 102, 202) of a double damping flywheel (1, 101, 201). intended to be fixed at the end of a crankshaft and the output element is a secondary flywheel (3, 103, 203) of the double damping flywheel which is intended to form a reaction plate for a clutch device.

Motor vehicle comprising a torque transmission device (1, 101, 201) according to any one of claims 1 to

17.