TORQUE VIBRATION DAMPER

Description

[0001] The invention relates to the field of torque transmission in motorized devices and concerns a torsional damping device for a vehicle transmission chain.

[0002] Motor vehicles generally incorporate torsional damping devices that can be integrated into various components of the drivetrain. For example, a dual-mass flywheel, a clutch disc, or a torque limiter may include a torsional damping device to filter out engine irregularities and other torsional oscillations. This filtering is typically achieved by one or more torsional dampers, which are spring-damper assemblies operating in torsion. During torque transmission, these dampers allow for a relative rotational movement between a first rotating torque transmission element, coupled upstream in the drivetrain, and a second rotating torque transmission element, coupled downstream in the drivetrain. This relative rotation can be achieved using springs arranged in series.During torque transfer, and particularly when the travel is close to 0°, there is a transfer of lift from these springs, allowing their compression, between the first and second rotating torque transmission elements. This transfer causes relative movements and, therefore, under the effect of centrifugal forces, radial friction that can damage the springs and significantly degrade the damping system's performance. Furthermore, these lift transfers are a source of noise.

[0003] US documents 5567845 A and US 4279132 A disclose a torsion damping device for a vehicle drive chain, respectively.

[0004] The invention aims to improve prior art torsional damping devices by proposing such a device insensitive to centrifugal forces.

[0005] To this end, the invention relates to a torsional damping device for a vehicle transmission chain, comprising: a first rotating element for transmitting a torque having a first housing, the first housing having a first support zone and a second opposing support zone, a second rotating element for transmitting the torque, an elastic device interposed between the first rotating element and the second rotating element, and allowing, when it deforms, a relative rotation about an axis of rotation between the first and second rotating elements, the elastic device comprising at least a first spring mounted in the first housing, the first spring comprising a first end and a second opposing end, the first rotating element being movable between a rest position, in which no spring of the elastic device is compressed, and an active position in which at least one spring of the elastic device is compressed,a first flange comprising a first compression tab arranged circumferentially between the first end of the first spring and the first rotating element, a second flange comprising a first compression tab arranged circumferentially between the second end of the first spring and the first rotating element, in which the first rotating element moves the first end of the first spring towards the second end of the first spring, via the first compression lug of the first flange, when said first rotating element is mobile in rotation in the forward direction from the rest position, and in which the first rotating element moves the second end of the first spring towards the first end of the first spring, via the first compression lug of the second flange, when said first rotating element is mobile in rotation in the reverse direction from the rest position, the first compression lug of the first flange being in contact with the first bearing area of ​​the first housing in the rest position.

[0006] Thus, eliminating load transfer during torque transmission reduces wear on the spring, or on parts in contact with it, and reduces noise during device operation. Eliminating load transfer also reduces, or even eliminates, radial friction for optimal damping performance. The presence of a first and second flange guiding the spring allows the first and second rotating elements to transmit only the torque without retaining the spring, or any intermediate element between the first rotating element and at least one other spring. This allows for standardization of the first rotating element and also increases its strength.

[0007] Furthermore, the first and second flanges do not react to the transmission of torque. Therefore, the dimensioning of these flanges is simpler and they are less expensive to manufacture.

[0008] The direct direction is the trigonometric direct direction, also called counterclockwise. The indirect direction is the trigonometric indirect direction, also called clockwise. The direct direction is the opposite of the indirect direction.

[0009] The torsional damping device may include the following additional features, alone or in combination.

[0010] The first compression lug of the first flange includes at least one retaining element adapted to radially hold the first spring. The retaining element is adapted to radially hold the spring when it is subjected to centrifugal forces. The retaining element prevents the spring from being lost. The retaining element facilitates the movement of the first end of the first spring through the first flange when the first rotating element is free to move in the forward direction from its rest position. The retaining element is a stud extending radially from the first compression lug towards the first spring between an end fixed to said first compression lug and a free end. The retaining element is an outer edge extending radially from an upper end of the first compression lug between an end fixed to said first compression lug and a free end.The retaining element is a nipple and an outer edge.

[0011] The elastic device further includes a second spring mounted in the first housing, the second spring comprising a first end and a second opposite end, the first compression lug of the second flange is arranged circumferentially between the second end of the second spring and the first rotating element, and the first rotating element moves the second end of the second spring towards the first end of the second spring, via the first compression lug of the second flange, when said first rotating element is mobile in rotation in the reverse direction from the rest position.

[0012] Thus, increasing the number of springs in the elastic device allows for increased damping performance while maintaining the advantages mentioned previously.

[0013] The first spring and the second spring are arranged in series by means of a phasing element connecting the second end of the first spring and the first end of the second spring.

[0014] The first rotating element is provided with a second housing; the elastic device further comprises a third spring, radially opposed to the first spring; the third spring being mounted in the second housing and comprising a first end and a second opposite end; the first flange and the second flange each comprise a second compression tab arranged circumferentially between the first rotating element and, respectively, the first end of the third spring or the second end of the third spring; the first rotating element moves the first end of the third spring towards the second end of the third spring, via the second compression tab of the first flange, when said first rotating element is free to rotate in the forward direction from the rest position, and it moves the second end of the third spring towards the first end of the third spring.via the second compression lug of the second flange, when said first rotating element is free to rotate in the reverse direction from its rest position.

[0015] Thus, the springs are diametrically opposed in pairs. In other words, the springs are radially aligned in pairs, or they are opposed in pairs with respect to the axis of rotation. Each flange is therefore connected to one end of two diametrically opposed springs.

[0016] This device configuration allows, under the effect of rotational speed, for the first and second compression tabs of the same flange to be subjected to two centrifugal forces from the mass of the springs. These two centrifugal forces are of equal magnitude but opposite in direction. Thus, the deformations related to these two centrifugal forces cancel each other out, and there is no longer any radial force acting on the first rotating element and / or the second rotating element, even when the rotation of the first rotating element changes from clockwise to counterclockwise or vice versa. Therefore, the balancing of centrifugal forces within the device eliminates friction, and thus the degradation of filtration performance associated with it. The device becomes insensitive to the negative effects of centrifugal forces.

[0017] The first rotating element is equipped with a second housing, the second housing having a first support zone and a second opposing support zone, The elastic device further comprises a third spring, radially opposed to the first spring, and a fourth spring, radially opposed to the second spring, the third and fourth springs being mounted in the second housing and each comprising a first end and a second opposite end, the first flange and the second flange each comprising a second compression tab arranged circumferentially between the first rotating element and, respectively, the first end of the third spring or the second end of the fourth spring, the first rotating element moves the first end of the third spring towards the second end of the third spring, via the second compression tab of the first flange, when said first rotating element is free to rotate in the forward direction from the rest position, and moves the second end of the fourth spring towards the first end of the fourth spring,via the second compression lug of the second flange, when said first rotating element is mobile in rotation in the indirect direction from the rest position, the second compression lug of the first flange being in contact with the first bearing area of ​​the second housing in the rest position.

[0018] Thus, the springs are diametrically opposed in pairs. Each of the flanges is thus connected to one end of two diametrically opposed springs, for example the first and third springs for the first flange and the second and fourth springs for the second flange.

[0019] This device configuration allows, under the effect of rotational speed, the first and second compression tabs of the same flange to be subjected to two centrifugal forces from the mass of the springs. These two centrifugal forces are of equal magnitude but opposite in direction. Thus, the deformations related to these two centrifugal forces cancel each other out, and there is no longer any radial force acting on the first rotating element and / or the second rotating element, even when the rotation of the first rotating element changes from the clockwise to the counterclockwise direction or reverse. Therefore, the balancing of centrifugal forces within the device eliminates friction, and thus the degradation of filtration performance associated with it. The device becomes insensitive to the negative effects of centrifugal forces.

[0020] The first flange moves in the clockwise direction between a predetermined initial position, in which the first flange does not compress the first spring, and an end-of-stroke position, in which the first flange compresses the first spring. This displacement is the predetermined stroke of the first flange. The second flange moves in the counterclockwise direction between a predetermined initial position, in which the second flange does not compress the second spring, and an end-of-stroke position, in which the second flange compresses the second spring. This displacement is the predetermined stroke of the second flange.

[0021] The second rotating element includes a circumferential stop, or the first compression lug of the first flange and the second compression lug of the second flange each include a stop, said stop(s) being respectively adapted to prohibit movement of the first flange in the indirect direction beyond a predetermined initial position and to prohibit movement of the second flange in the direct direction beyond a predetermined initial position.

[0022] Thus, when the second rotating element includes the stop, the stop prevents both the first and second flanges from exceeding their predetermined travel, namely between their predetermined initial position and their end-of-travel position, by stopping them. The stop is a limit switch element.

[0023] The stop is located circumferentially between the first compression lug of the first flange and the second compression lug of the second flange.

[0024] The second rotating element includes two stops. The first stop is designed to prevent the first compression tab of the first flange from traveling beyond its predetermined stroke and the second compression tab of the second flange from traveling beyond its predetermined stroke. The second stop is designed to prevent the second compression tab of the first flange and the first compression tab of the second flange from traveling beyond its predetermined stroke. This improves the control of the first and second flanges' travel.

[0025] The stop is a stamped part made in the second rotating element. Thus, the stop is of simple design, inexpensive, and compact.

[0026] When the first compression lug of the first flange and the second compression lug of the second flange each include a stop, the stop on the first compression lug of the first flange prevents the first flange from moving beyond its predetermined stroke, namely between its predetermined initial position and its end-of-stroke position, by stopping the movement of said first flange in the indirect direction, and the stop on the first compression lug of the second flange prevents the second flange from moving beyond its predetermined stroke, namely between its predetermined initial position and its end-of-stroke position, by stopping the movement of said second flange in the direct direction. The stops are end-of-stroke elements.

[0027] The second compression tab of both the first and second flanges includes a stop. The stops on the first and second compression tabs of the first flange are designed to prevent the first flange from moving beyond its predetermined stroke. The stops on the first and second compression tabs of the second flange are designed to prevent the first flange from moving beyond its predetermined stroke. This improves control of the first and second flanges' stroke.

[0028] The stops are each a shoulder cut respectively on the first leg of the first bridle and the second bridle. Thus, the stops are simple in design, inexpensive, and compact.

[0029] The first and / or second flange comprises a single, one-piece balancing disc that rotates around the axis of rotation and forms the first compression lug. Thus, the first and / or second flange is made from a single piece, reducing manufacturing costs and simplifying device assembly.

[0030] The first compression leg has an inclined U-shape. This shape is also called a suitcase wedge. The shape comprises a main wall and two radial side walls. The inclined U-shape of the first compression leg is created by stamping. This inclined U-shape ensures a good interface with the springs.

[0031] The second compression tab has the same shape as the first compression tab.

[0032] The first and / or second flange comprises a single balancing disc that rotates around the axis of rotation, and an end piece attached to this single balancing disc, forming the first compression lug. The single balancing disc is made of metal. The end piece is made of plastic and is overmolded onto the single balancing disc. Thus, the first and / or second flange is manufactured with a limited number of parts, which helps to keep costs down and allows the different parts to be adapted to their function.

[0033] The first flange and / or the second flange includes a second end piece attached to the single balancing disc and forming the second compression lug.

[0034] The first and second flanges are positioned axially on either side of the first rotating element. In other words, the first rotating element is axially interposed between the first and second flanges. This optimizes the axial footprint of the device.

[0035] The first flange and / or the second flange includes a first balancing disc, a second balancing disc, rotationally fixed to the first balancing disc, and an end piece forming the first compression lug.

[0036] The first balancing disc is riveted to the second balancing disc. This provides a robust and easily implemented means of joining the two balancing discs.

[0037] The first balancing disc and the second balancing disc are mobile in rotation around the axis of rotation.

[0038] The first and second balancing discs are exactly the same. Therefore, only one part number is needed, which reduces manufacturing costs.

[0039] The first balancing disc and / or the second balancing disc is a stamped sheet metal.

[0040] The first and / or second flange includes a second stamped part forming the second compression tab. This second stamped part is identical to the first. Therefore, only one part number is required, which reduces manufacturing costs.

[0041] The first balancing disc of the first flange and the first balancing disc of the second flange are located axially on one side of the first rotating element, and the second balancing disc of the first flange and the second balancing disc of the second flange are located axially on the other side of the first rotating element. Thus, the flanges exhibit excellent mechanical strength.

[0042] One of the first rotating element and the second rotating element is coupled in rotation to a hub, the first flange and / or the second flange being guided in rotation by said hub.

[0043] The device further includes a friction system comprising a friction washer, arranged to rub directly or indirectly against the first or second rotating element, and driven in rotation by the first or second flange.

[0044] Thus, the friction system allows for differentiation between the direct and indirect directions.

[0045] The friction washer is arranged to rub directly or indirectly against the second rotating element and the friction system further includes an actuating washer having an axial finger cooperating with a notch in the friction washer to ensure the drive of the friction washer by the actuating washer when the second flange is movable in rotation.

[0046] Since friction is particularly significant in the reverse direction, especially during start-up in hybrid vehicles, the friction system is especially effective in this direction. The friction system has fewer parts and is more robust.

[0047] The friction system further includes an axial support fixed in rotation to the second rotating element and an elastic washer arranged between the axial support and the friction washer so as to exert an axial force on the friction washer in the direction of the second rotating element.

[0048] The invention also relates, according to another aspect, to a vehicle powertrain comprising: a thermal engine and / or an electric motor for vehicle propulsion, and a torsional damping device according to the invention.

[0049] In the description and claims, the terms "compressed" or "compression", on the one hand, and "pre-stressed" or "pre-stressed", on the other hand, when referring to springs, are used as follows: The preload of a spring refers to the fact that this spring is mounted in a housing which is smaller than the initial length of the spring, the latter therefore exerting, by its elasticity, a force against at least one of the walls of the housing; the compression of a spring refers to the fact that this spring is compressed by bringing two moving parts closer together.

[0050] The preload of a spring is therefore effective even when the torsional damping device is at rest, without any torque being transmitted. The compression of a spring, however, only occurs during torque transmission; moving parts relative to each other modify the configuration of the spring housing and compress it.

[0051] By "vehicle" we mean motor vehicles, which include not only passenger vehicles but also industrial vehicles, which notably includes heavy goods vehicles, public transport vehicles or agricultural vehicles, but also any transport device enabling the movement of a living being and / or an object from one point to another.

[0052] A preferred embodiment of the invention will now be described with reference to the accompanying drawings in which: [ Fig. 1 ] is an exploded view of a torsional damping device according to the invention; [ Fig. 2 ] is a partial perspective view of the torsional damping device, with the first flange and the second flange in their predetermined initial position; [ Fig. 3 ] is a partial perspective view of the torsional damping device, with the first flange in the end-of-stroke position; [ Fig. 4 ] is a partial perspective view of the torsional damping device, with the second flange in the end-of-stroke position; [ Fig. 5 ] is a partial cross-sectional view of the torsional damping device, including a friction system; [ Fig. 6 ] is a partial perspective view of the torsional damping device, including a stop; [ Fig. 7 ] is a perspective view of an initial variant of a flange design; [ Fig. 8 ] is a perspective view of a second variant of a flange design; [ Fig. 9 ] is a partial perspective view of the torsional damping device, including a flange according to a third embodiment variant;

[0053] In the description and claims, the terms "external" and "internal," as well as the orientations "axial" and "radial," will be used to designate, according to the definitions given in the description, elements of the damping device. The axis of rotation X determines the "axial" orientation. The "radial" orientation is directed orthogonally to the axis of rotation X. The "circumferential" orientation is directed orthogonally to the axis of rotation X and orthogonally to the radial direction. The terms "external" and "internal" are used to define the relative position of one component with respect to another, with reference to the axis of rotation X; a component close to this axis is thus described as internal, as opposed to an external component located radially at the periphery. Furthermore, the angles and angular sectors expressed are defined in relation to the axis of rotation X.

[0054] There figure 1 represents a torsional damping device 1.

[0055] The damping device 1 may include a peripheral torque transmission element and a central torque transmission element consisting here of a hub 5.

[0056] The peripheral torque transmission element can, for example, be a friction disc of a torque limiter (not shown) intended, in normal operation, to transmit a torque by rotating around an axis of rotation X and to limit this transmission when this torque exceeds a certain value.

[0057] The peripheral torque transmission element can be fixed, for example by a first set of rivets, to a first rotating torque transmission element which is here constituted by a disc called a "sail" 7. The sail 7 can be included by the device 1.

[0058] The hub 5 can be fixed by a second set of rivets 2 to a second rotating torque transmission element which here consists of a pair of discs called "guide washers" 9, 10. The guide washers 9, 10 can form a cover for the device 1. A first guide washer 9 is fixed against one side of the hub 5 while a second guide washer 10 is fixed against an opposite side of the hub 5. The guide washers 9, 10 can be included by the device 1.

[0059] The roles of the web and the guide washers can be reversed, with the web becoming the second rotating element and the guide washers becoming the first rotating element.

[0060] The damping device 1 includes an elastic damping device 11 interposed between the web 7 and the guide washers 9, 10. The elastic device 11 is adapted so that the web 7 on the one hand, and the guide washers 9, 10 on the other hand, can rotate relative to each other by compressing the elastic device 11.

[0061] The damping device 1 is designed to be mounted in a torque transmission chain, for example, between an engine and the wheels of a vehicle. The peripheral torque transmission element can be pressed against a support disc, which is attached to a flywheel, by means of an elastically loaded pressure disc. The hub 5 can be connected to a drive shaft. The drive element rotates the peripheral torque transmission element and thus the disc 7 attached to it. The disc 7 compresses the elastic device 11, via one of a first flange 30 and a second flange 40, which transmits the torque to the guide washers 9, 10 and thus to the hub 5 attached to it, via the other of the first flange 30 and the second flange 40.By transmitting the torque between the veil 7 and the guide washers 9, 10, the elastic device 11, by its elastic properties, filters out acyclic movements and other undesirable torsional movements.

[0062] Device 1 can operate dry or in an environment containing grease or oil.

[0063] The damping device 1 further includes a first end stop and a second complementary end stop allowing the torque to be directly transmitted from the peripheral torque transmission element to the hub 5, short-circuiting the elastic device 11 beyond a predetermined angle of relative rotation between the web 7 and the guide washers 9, 10.

[0064] The first end stop is here made up of external teeth arranged around the perimeter of the hub 5 and the second complementary end stop is here made up of internal teeth 4 in the center of the web 7.

[0065] The elastic damping device 11 includes a first spring 13. The first spring 13 may be straight. Alternatively, the first spring 13 may be curved.

[0066] The elastic damping device 11 may further include a third spring 15. The third spring 15 may be straight. Alternatively, the third spring 15 may be curved. The first spring 13 may be diametrically opposite, with respect to the axis of rotation X, to the third spring 15.

[0067] The first spring 13 extends between a first end 131 and a second end 132. The third spring 15 extends between a first end 151 and a second end 152.

[0068] The veil 7 includes a first opening defining a first housing 17. The first spring 13 can be mounted in the first housing 17. The veil 7 may further include a second opening defining a second housing 18. The third spring 15 can be mounted in the second housing 18.

[0069] Each of the housings 17, 18 of the veil 7 presents a first support zone 19 and a second opposing support zone 20.

[0070] The veil 7 comprises two diametrically opposed arms 6. Each of the arms 6 can form a separation between the first housing 17 and the second housing 18. The springs 13, 15 are mounted between the arms 6.

[0071] The guide washers 9, 10 each have openings 12 to allow the mounting of the springs 13, 15. The edges of said openings are at a distance from the springs 13, 15.

[0072] The functions of the elastic device 11 can be ensured by a single spring or by any number of springs, possibly in series or in parallel.

[0073] The veil 7 can be mobile in rotation between a rest position, in which no spring 13, 15 of the elastic device 11 is compressed, and an active position in which the springs 13, 15 of the elastic device 11 are compressed.

[0074] Device 1 further includes the first flange 30 and the second flange 40.

[0075] The first flange 30 and the second flange 40 can be free to rotate about the axis of rotation X. The first flange 30 and the second flange 40 can be guided by the hub 5. The first flange 30 and the second flange 40 can be mounted axially on either side of the web 7.

[0076] The first flange 30 can be radially centered directly on the guide washers 9, 10 or the web 7. Alternatively, the first flange 30 can be radially centered indirectly on the guide washers 9, 10 or the web 7.

[0077] The second flange 40 can be radially centered directly on the guide washers 9, 10 or the web 7. Alternatively, the second flange 40 can be radially centered indirectly on the guide washers 9, 10 or the web 7.

[0078] The first flange 30 includes at least one balancing disc 31, a first compression lug 32 and a second compression lug 33.

[0079] The balancing disc 31 can be a stamped sheet metal.

[0080] The first compression lug 32 and the second compression lug 33 may each include a bearing surface 34 adapted to receive one end of one of the springs 13, 15. The first compression lug 32 and the second compression lug 33 may further each include a pin 35 extending radially from the bearing surface 34 between an end fixed to said bearing surface and a free end. The pin 35 may be a retaining element adapted to radially retain one of the springs. The pin 35 may be adapted to radially retain one of the springs when the latter is subjected to centrifugal forces. The pin 35 may also be adapted to axially retain one of the springs 13, 15.The first compression lug 32 and the second compression lug 33 may each further comprise an external edge 36 extending radially from the upper end of the bearing face 34 between an end fixed to said bearing face and a free end. The edge 36 may be a retaining element adapted to radially hold one of the springs. The edge 36 may be adapted to radially hold one of the springs when the latter is subjected to centrifugal forces.

[0081] The first compression tab 32 of the first flange 30 can be arranged circumferentially between the first end 131 of the first spring 13 and the web 7. More specifically, the first compression tab 32 of the first flange 30 can bear against the first bearing area 19 of the first housing 17 of the web 7 when the device 1 is in a rest state. This rest state of the device 1 is a state in which the web 7 is in a rest position. The rest position of the web 7 is a position in which the web 7 is at a distance from the springs 13, 15. That is to say, the web 7 is not compressing either of the springs 13, 15. This rest state of the device 1 is a state in which the first flange 30 is in the predetermined initial position. The bearing face 34 of the first compression leg 32 of the first flange 30 can bear against the first end 131 of the first spring 13.

[0082] The second compression tab 33 of the first flange 30 can be arranged circumferentially between the first end 151 of the third spring 15 and the web 7. More specifically, the second compression tab 33 of the first flange 30 can bear against the first bearing area 19 of the second housing 18 of the web 7 when the device 1 is in its rest state. In this rest state of the device 1, the first flange 30 is in its predetermined initial position and the web 7 is in its rest position. The bearing face 34 of the second compression tab 33 of the first flange 30 can bear against the first end 151 of the third spring 15.

[0083] The balancing disc 31, which rotates about the axis of rotation X, may be a single unit. The balancing disc 31 may be a single piece. The balancing disc 31 may form the first compression lug 32 and the second compression lug 33. The first compression lug 32 and the second compression lug 33 may have an inclined U-shape. This shape is also called a suitcase wedge. The shape comprises a main wall and two lateral walls radial to the main wall. One of the lateral walls may form the edge 36. The inclined U-shape of the first compression lug is formed by stamping.

[0084] The second flange 40 includes at least one balancing disc 41, a first compression lug 42 and a second compression lug 43.

[0085] The balancing disc 41 can be a stamped sheet metal.

[0086] The first compression lug 42 and the second compression lug 43 may each include a bearing surface 44 adapted to receive one end of one of the springs 13, 15. The first compression lug 42 and the second compression lug 43 may further each include a pin 45 extending radially from the bearing surface 44 between an end fixed to said bearing surface and a free end. The pin 45 may be a retaining element adapted to radially retain one of the springs. The pin 45 may be adapted to radially retain one of the springs when the latter is subjected to centrifugal forces. The pin 45 may also be adapted to axially retain one of the springs 13, 15.The first compression lug 42 and the second compression lug 43 may each further comprise an external edge 46 extending radially from the upper end of the bearing face 44 between an end fixed to said bearing face and a free end. The edge 46 may be a retaining element adapted to radially hold one of the springs. The edge 46 may be adapted to radially hold one of the springs when the latter is subjected to centrifugal forces.

[0087] The first compression tab 42 of the second flange 40 can be arranged circumferentially between the second end 132 of the first spring 13 and the web 7. More specifically, the first compression tab 42 of the second flange 40 can bear against the second bearing area 20 of the first housing 17 of the web 7 when the device 1 is in its rest state. In this rest state of the device 1, the second flange 40 is in its predetermined initial position and the web 7 is in its rest position. The bearing face 44 of the first compression tab 42 of the second flange 40 can bear against the second end 132 of the first spring 14.

[0088] The second compression tab 43 of the second flange 40 can be arranged circumferentially between the second end 152 of the third spring 15 and the web 7. More specifically, the second compression tab 43 of the second flange 40 can bear against the second bearing area 20 of the second housing 18 of the web 7 when the device 1 is in its rest state. In this rest state of the device 1, the second flange 40 is in its predetermined initial position and the web 7 is in its rest position. The bearing face 44 of the second compression tab 43 of the second flange 40 can bear against the second end 122 of the third spring 15.

[0089] The angle of attack of at least one of the springs 13, 14, 15, 16 by one of the compression lugs has a value between 0 and 20° (degrees).

[0090] The balancing disc 41, which rotates about the axis of rotation X, may be a single unit. The balancing disc 41 may be a single piece. The balancing disc 41 may form the first compression lug 42 and the second compression lug 43. The first compression lug 42 and the second compression lug 43 may have an inclined U-shape. This shape is also called a wedge shape. The shape comprises a main wall and two lateral walls radial to the main wall. One of the lateral walls may form the edge 46. The inclined U-shape of the first compression lug is formed by stamping.

[0091] In the axial direction, we find the first flange 30, the veil 7 then the second flange 40.

[0092] The elastic damping device 11 may further include a second spring 14 and a fourth spring 16. The springs 13, 14, 15, and 16 may be arranged circumferentially. The springs 13, 14, 15, and 16 may be arranged in series. The springs 14 and 16 may be straight. Alternatively, the springs 14 and 16 may be curved. The second spring 14 may be diametrically opposite, with respect to the axis of rotation X, the fourth spring 16.

[0093] The second spring 14 extends between a first end 141 and a second end 142. The fourth spring 16 extends between a first end 161 and a second end 162.

[0094] The first spring 13 and the second spring 14 can be mounted in the first housing 17 of the sail 7. The third spring 15 and the fourth spring 16 can be mounted in the second housing 18 of the sail 7. The springs 13, 14, 15, 16 are mounted between the arms 6 of the sail 7.

[0095] The openings 12 of the guide washers 9, 10 allow the mounting of the springs 13, 14, 15, 16. The edges of said openings are at a distance from the springs 13, 14, 15, 16.

[0096] The elastic damping device 11 further includes a phasing element 50 for the springs 13, 14, 15, 16. The phasing element 50 comprises two spacers 51 mounted, diametrically opposite, axially between two phasing disks 52. The first spacer 51 can be mounted circumferentially between the first spring 13 and the second spring 14. The second spacer 51 can be mounted circumferentially between the third spring 15 and the fourth spring 16.

[0097] Each spacer 51 may include two end pieces 53. The two end pieces may be identical. The two end pieces may form a single piece. Each end piece 53 may be made of sintered steel. Each end piece 53 may include a bearing face 54 adapted to receive one end of a spring. Each end piece 53 may further include a stud 55 extending radially from the bearing face 54 between an end fixed to said bearing face and a free end. The stud 55 may be a retaining element adapted to radially retain one of the springs. The stud 55 may be adapted to radially retain one of the springs when the latter is subjected to centrifugal forces. The stud 55 may also be adapted to axially retain one of the springs 13, 14, 15, 16.Each of the end pieces 53 may further include an external edge 56 extending radially from the upper end of the bearing face 54 between an end fixed to said bearing face and a free end. The edge 56 may be a retaining element adapted to radially hold one of the springs 13, 14, 15, 16. The stud 56 may be adapted to radially hold one of the springs 13, 14, 15, 16 when the latter is subjected to centrifugal forces.

[0098] The first end 53 of the first spacer 51 can be in contact with the second end 132 of the first spring 13 and the second end 53 of the first spacer can be in contact with the first end 141 of the second spring 14. The first end 53 of the second spacer 51 can be in contact with the second end 152 of the third spring 15 and the second end 53 of the second spacer can be in contact with the first end 161 of the fourth spring 16.

[0099] The phasing discs 52 and each of the end pieces 53 can be fixed together by rivets 57.

[0100] The bearing faces 34 of the first compression lug 32 and the second compression lug 33 can each be adapted to receive one of the ends of one of the springs 13, 14, 15, 16. The nipple 35 can be adapted to axially retain one of the springs 13, 14, 15, 16. The edge 36 can be adapted to radially retain one of the springs 13, 14, 15, 16.

[0101] The bearing faces 44 of the first compression lug 42 and the second compression lug 43 can each be adapted to receive one of the ends of one of the springs 13, 14, 15, 16. The pin 45 can be adapted to axially retain one of the springs 13, 14, 15, 16. The edge 46 can be adapted to radially retain one of the springs 13, 14, 15, 16.

[0102] When the elastic device 11 comprises the four springs 13, 14, 15, 16, the first compression tab 42 of the second flange 40 can be arranged circumferentially between the second end 142 of the second spring 14 and the web 7. More specifically, the first compression tab 42 of the second flange 40 can bear against the second bearing area 20 of the first housing 17 of the web 7 when the device 1 is in its rest state. In this rest state of the device 1, the second flange 40 is in its predetermined initial position and the web 7 is in its rest position. The bearing face 44 of the first compression tab 42 of the second flange 40 can bear against the second end 142 of the second spring 14.

[0103] The second compression tab 43 of the second flange 40 can be arranged circumferentially between the second end 162 of the fourth spring 16 and the web 7. More specifically, the second compression tab 43 of the second flange 40 can bear against the second bearing area 20 of the second housing 18 of the web 7 when the device 1 is in its rest state. In this rest state of the device 1, the second flange 40 is in its predetermined initial position and the web 7 is in its rest position. The bearing face 44 of the second compression tab 43 of the second flange 40 can bear against the second end 162 of the fourth spring 16.

[0104] The second embodiment of the first flange 30' differs from the first embodiment of the first flange 30 in that:

[0105] The first flange 30' may further include two end pieces 37'. The two end pieces 37' are integral with the single balancing disc 31'. The first end piece 37' may form the first compression lug 32. The second end piece 37' may form the second compression lug 33. The single balancing disc 31' may be made of metal. Each of the end pieces 37' may be made of plastic and is overmolded onto an arm of the single balancing disc 31'.

[0106] The characteristics of this second variant are also valid for the second flange.

[0107] The third embodiment of the first 30" flange differs from the first embodiment of the first 30" flange in that:

[0108] The first 30" flange can include two 31" balancing discs and two 37" end pieces. The first balancing disc can be rotationally fixed to the second balancing disc. The first 31" balancing disc and the second 31" balancing disc are identical. The two 37" end pieces are fixed to the single 31" balancing disc. The first 37" end piece can form the first compression lug 32. The second 37" end piece can form the second compression lug 33. The second end piece is identical to the first 37" end piece. The two 31" balancing discs can be made of stamped sheet metal. Each of the 37" end pieces can be made of sintered steel. The first balancing disc is riveted to the second balancing disc. The 37" end pieces can be riveted to both 31" balancing discs.

[0109] The characteristics of this third variant are also valid for the second 40" flange.

[0110] The first 31" balancing disc of the first 30" flange and the first 41" balancing disc of the second 40" flange are located axially on one side of the web 7, and the second 31" balancing disc of the first 30" flange and the second 41" balancing disc of the second 40" flange are located axially on the other side of the web 7.

[0111] The damping device 1 may further include a friction system 60 designed to dissipate the energy of the springs 13, 14, 15, 16 and to prevent oscillations. The friction system 60 comprises an axial support 61 fixed against the second guide washer 10 by a third set of rivets 62. Between the axial support 61 and the second guide washer 10 are arranged: a friction washer 63, an intermediate washer 64, and a spring washer 65, the latter applying a load to the friction washer 63 via the intermediate washer 64.

[0112] The axial support 61 can also be made in one piece with the guide washer 10.

[0113] Furthermore, the second flange 40 is provided on the opposite side of the second guide washer 10. The second flange 40 may also include at least one toothed section. The toothed section is adapted to actuate an additional friction washer comprising one axial finger 49, and preferably four axial fingers 49. The additional friction washer may be made of plastic. The additional friction washer may be mounted so that the four axial fingers 49 pass through four corresponding grooves 8 formed in the second guide washer 10. Each of the four axial fingers 49 is inserted into a notch 69 in the friction washer 63. The second flange 40 is thus rotationally coupled to the friction washer 69.

[0114] At least one of the guide washers 9, 10 may include a stop 21. The stop 21 is adapted to prevent the first flange 30 from moving in the indirect direction beyond its predetermined initial position and to prevent the second flange 40 from moving in the direct direction beyond its predetermined initial position. The stop 21 may be located circumferentially between the first compression lug 32 of the first flange 30 and the second compression lug 43 of the second flange 40.

[0115] The stop 21 can be a stamping made in at least one of the guide washers 9, 10.

[0116] At least one of the guide washers 9, 10 may include two stops 21.

[0117] Alternatively, the compression tabs 32, 33, 42, 43 of the first and second flanges may each include a stop 23. The stops 23 are adapted to prevent the first flange 30 from moving in the indirect direction beyond its predetermined initial position and to prevent the second flange 40 from moving in the direct direction beyond its predetermined initial position. More specifically, the stops 23 located on the first flange 30 are adapted to prevent the first flange 30 from moving in the indirect direction beyond its predetermined initial position. The stops 23 located on the second flange 40 are adapted to prevent the second flange 40 from moving in the direct direction beyond its predetermined initial position.

[0118] The stops 23 can each be a shoulder made respectively on the compression tabs of the flanges.

[0119] The assembly of device 1 is shown in the view of the figure 2 . This figure 2 shows device 1 in the rest state, that is to say when it does not transmit any torque, springs 13, 14, 15, 16 not being stressed. Each spring 13, 14, 15, 16 is mounted, at one of its ends, in a compression tab 32, 33, 42, 43 and, at the other of its ends, against one of the spacers 51. Each compression tab 32, 33, 42, 43 is supported only on the web 7. Thus, the first pair of springs 13, 14 is mounted between the first compression tab 32 of the first flange 30, which supports for example only on the first bearing area 19 of the first housing 17 of the web 7, and the first compression tab 42 of the second flange 40, which supports for example only on the second bearing area 20 of the first housing 17 of the web 7.In addition, the second pair of springs 15, 16 is mounted between the second compression lug 33 of the first flange 30, which rests for example only on the first bearing area 19 of the second housing 18 of the web 7, and the second compression lug 43 of the second flange 40, which rests for example only on the second bearing area 20 of the second housing 18 of the web 7.

[0120] The springs 13, 14, 15, 16 are thus, in pairs, prestressed between the first support zones 19 and the second support zones 20. Between the springs 13, 14, 15, 16 of each pair, the spacer 51, movable in rotation around the X axis thanks to the phasing discs 52, ensures the series connection of the springs 13, 14, 15, 16 of a pair, as well as the phasing, that is to say the angular coordination, of one pair with the other.

[0121] The angular rest position is the initial position from which the following are characterized: a first polarity of torque defined by the fact that the veil 7 is in an angular position, relative to the guide washers 9, 10, which is located in an angular sector between the predetermined initial position, also called the angular rest position, in which the veil 7 is in the rest position, and an end-of-stroke position where the veil 7 is in the active position, i.e. turned to the maximum in the direct direction, until the teeth 3, 6 come to a stop;a second polarity of torque defined by the fact that the veil 7 is in an angular position, relative to the guide washers 9, 10, which is located in an angular sector between the predetermined initial position, also called the angular rest position, in which the veil 7 is in the rest position, and an end-of-stroke position where the veil 7 is in the active position, i.e. turned to the maximum in the indirect direction, until the teeth 3, 6 come to a stop. ;

[0122] These two torque polarities correspond to two operating modes of the torsional damping device 1: a mode where the torque is transmitted from the central torque transmission element to the peripheral torque transmission element, corresponding for example, in a vehicle, to a transmission of torque from the wheels to the engine (engine braking phases, for example) commonly called "reverse mode", this corresponds to the second torque polarity; a mode where the torque is transmitted from the peripheral torque transmission element to the central torque transmission element, corresponding for example, in a vehicle to a transmission of torque from the engine to the wheels (acceleration phases, for example) commonly called "direct mode", this corresponds to the first torque polarity.

[0123] There figure 3 is relative to disk 1 in the first torque polarity. With respect to the angular rest position of the figure 2 , the veil 7 has rotated in the forward direction until it reaches its end-of-stroke position (arrow D). In this position, the springs 13, 14, 15, 16 are compressed between the first support zones 19 of the veil 7 and the compression tabs 42, 43 of the second flange 40.

[0124] There figure 4 is relative to disk 1 in the second torque polarity. With respect to the angular rest position of the figure 7 The veil 7 has now rotated in the reverse direction to its end-of-stroke position (arrow I). In this position, the springs 13, 14, 15, 16 are compressed between the second support zones 20 of the veil 7 and the compression tabs 32, 33 of the first flange 30.

[0125] Depending on whether the torsional damping device 1 works according to one or the other of these torque polarities, the operation of the friction system 60 is different.

[0126] When the torsional damping device 1 is subjected to the first torque polarity, this is equivalent, on the figure 3 The movement of the web 7 along arrow D occurs while the guide washer 10 remains fixed. The web 7 then drives, via the first bearing areas 19, the compression tabs 32 and 33 of the first flange 30 and compresses the first spring 13 and the third spring 15 respectively against one of the spacers 51. These spacers 51, in turn, compress the second and fourth springs respectively against the first and second compression tabs of the second flange 40. The second bearing areas 20 of the web 7 then move away from the compression tabs 42 and 43 of the second flange 40. The friction system 60 is not in operation. As nothing is exerting stress on the second flange 40, it does not move.

[0127] Conversely, when the torsional damping device 1 is subjected to the second torque polarity, this equates to a movement of the web 7 along arrow I, with the guide washer 10 remaining fixed. The web 7 then drives, via the second bearing zones 20, the compression tabs 42, 43 of the second flange 40 and compresses the second spring 14 and the fourth spring 16 respectively against one of the spacers 51. These spacers 51, in turn, compress the first and third springs respectively against the first and second compression tabs of the first flange 30. The first bearing zones 19 of the web 7 then move away from the compression tabs 32, 33 of the first flange 30. The friction system 60 is in operation since the movement of the second flange 40 causes the friction washer 63 to move, which therefore rubs against the guide washer 10 and the spacer washer 64.

[0128] According to the first torque polarity, the friction system 60 is thus deactivated, while it is activated according to the second torque polarity.

[0129] Other embodiments of the torsional damping device 1 can be implemented. For example, the system in which the torsional damping device is mounted can be any system within a torque transmission chain that requires torsional damping, such as a clutch disc.

Claims

1. Torsion damping device (1) for a vehicle transmission chain, comprising: - a first rotating element (7) for transmitting a torque provided with a first housing (17), the first housing (17) having a first bearing zone (19) and an opposing second bearing zone (20), - a second rotating element (9, 10) for transmitting the torque, - an elastic device (11) interposed between the first rotating element (7) and the second rotating element (9, 10), and allowing, when it deforms, a relative rotation around a rotation axis (X) between the first (7) and second (9, 10) rotating elements, the elastic device (11) comprising at least one first spring (13) mounted in the first housing (17), the first spring (13) comprising a first end (131) and an opposing second end (132), the first rotating element (7) being movable between a rest position, in which no spring of the elastic device is compressed, and an active position in which the at least one spring of the elastic device is compressed, - a first flange (30; 30'; 30") comprising a first compression tab (32) arranged circumferentially between the first end (131) of the first spring (13) and the first rotating element (7), - a second flange (40; 40') comprising a first compression tab (42) arranged circumferentially between the second end (132) of the first spring (13) and the first rotating element (7), wherein the first rotating element (7) moves the first end (131) of the first spring (13) toward the second end of the first spring, via the first compression tab of the first flange (30; 30'; 30"), when said first rotating element (7) is rotatably movable in the forward direction from the rest position, and wherein the first rotating element (7) moves the second end (132) of the first spring (13) toward the first end of the first spring, via the first compression tab of the second flange (40; 40'), when said first rotating element (7) is rotatably movable in the reverse direction from the rest position, the first compression tab (32) of the first flange (30) being in abutment against the first bearing zone (19) of the first housing (17) in the rest position.

2. Device (1) according to the preceding claim, characterized in that the first compression tab (32) of the first flange (30; 30'; 30") comprises at least one retaining element (35, 55, 36, 56) adapted to radially retain the first spring (13).

3. Device (1) according to Claim 1 or Claim 2, characterized in that the elastic device (11) further comprises a second spring (14) mounted in the first housing (17), the second spring (14) comprising a first end (141) and an opposing second end (142), in that the first compression tab (42) of the second flange (40; 40") is arranged circumferentially between the second end (142) of the second spring (14) and the first rotating element (7), and in that the first rotating element (7) moves the second end (142) of the second spring (14) toward the first end of the second spring, via the first compression tab of the second flange (40; 40"), when said first rotating element (7) is rotatably movable in the reverse direction from the rest position.

4. Device (1) according to the preceding claim, characterized in that the first spring (13) and the second spring (14) are arranged in series by means of a phasing element (50) connecting the second end of the first spring (13) and the first end of the second spring (14).

5. Device (1) according to Claim 3 or Claim 4, characterized in that the first rotating element (7) is provided with a second housing (18), the second housing (18) having a first bearing zone (19) and an opposing second bearing zone (20), in that the elastic device (11) further comprises a third spring (15), radially opposite the first spring (13), and a fourth spring (16), radially opposite the second spring (14), the third and fourth springs being mounted in the second housing (18) and each comprising a first end (151, 161) and an opposing second end (152, 162), in that the first flange (30; 30'; 30') and the second flange (40; 40") each comprise a second compression tab (33, 43) arranged circumferentially between the first rotating element (7) and, respectively, the first end (151) of the third spring (15) or the second end of the fourth spring (16), and in that the first rotating element (7) moves the first end (151) of the third spring (15) toward the second end of the third spring, via the second compression tab of the first flange (30; 30'; 30"), when said first rotating element (7) is rotatably movable in the forward direction from the rest position, and moves the second end (162) of the fourth spring (16) toward the first end of the fourth spring, via the second compression tab of the second flange (40; 40"), when said first rotating element (7) is rotatably movable in the reverse direction from the rest position, the second compression tab (33) of the first flange (30) being in abutment against the first bearing zone (19) of the second housing (18) in the rest position.

6. Device (1) according to the preceding claim, characterized in that the second rotating element (9, 10) comprises a circumferential stop (21), or in that the first compression tab (32) of the first flange (30; 30'; 30") and the second compression tab (43) of the second flange (40; 40") each comprise a stop (23), said stop or stops being respectively adapted to prevent the movement of the first flange (30; 30'; 30") in the reverse direction beyond a predetermined initial position and to prevent the movement of the second flange (40; 40') in the forward direction beyond a predetermined initial position.

7. Device (1) according to any one of the preceding claims, characterized in that the first flange (30; 30') and / or the second flange (40) comprises a single one-piece balancing disc (31, 41) rotatably movable about the rotation axis (X) and forming the first compression tab, or comprises a single balancing disc (31') rotatably movable about the rotation axis (X) and a tip (37'), integral with said single balancing disc (31'), forming the first compression tab (32, 42).

8. Device (1) according to any one of the preceding claims, characterized in that the first flange (30; 30'; 30") and the second flange (40; 40') are located axially on either side of the first rotating element (7).

9. Device (1) according to any one of Claims 1 to 6, characterized in that the first flange (30") and / or the second flange (40") comprises a first balancing disc, a second balancing disc (31", 41"), rotationally integral with the first balancing disc, and a tip (37") forming the first compression tab (32, 42).

10. Device (1) according to the preceding claim, characterized in that the first balancing disc of the first flange (30") and the first balancing disc of the second flange (40") are located axially on one side of the first rotating element (7), and in that the second balancing disc of the first flange (30") and the second balancing disc of the second flange (40") are located axially on the other side of the first rotating element (7).

11. Device (1) according to any one of the preceding claims, characterized in that one of the first rotating element (7) and the second rotating element (9, 10) is rotationally coupled to a hub (5), the first flange and / or the second flange being rotationally guided by said hub.

12. Device (1) according to any one of the preceding claims, characterized in that the device further comprises a friction system (60) comprising a friction washer (63), arranged to rub directly or indirectly against the first or second rotating element, and driven in rotation by the first or second flange.