FR3034482A1 - DOUBLE FLYWHEEL TORQUE TRANSMISSION DAMPER, IN PARTICULAR FOR A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a double damping flywheel comprising a primary flywheel (2) and a secondary flywheel (3), the secondary flywheel (3) being able to pivot about an axis X relative to at the primary flywheel (2), torsion damping means (10, 16a, 16b) being mounted between the primary (2) and secondary (3) flywheels, the double damping flywheel (1) comprising an annular hub (28) of axis X, intended to be coupled to a gearbox shaft, and a connecting member (23) belonging to the secondary flywheel (3) and coupled in rotation along the X axis with the hub (28), characterized in that Y and Z axes are defined so that the X, Y and Z axes form an orthonormal coordinate system, the connecting member (23) and the hub (28) being coupled via a link permitting a rotation along at least one of the Y and Z axes, the double damping flywheel having means for biasing elastics able to maintain the connecting member (23) bearing on the hub (28).

Description

The present invention relates to a double damping flywheel, especially for a motor vehicle.

A double damping flywheel (DVA) conventionally comprises a primary flywheel intended to be coupled to a driving shaft, such as for example a crankshaft of an internal combustion engine of a motor vehicle, a secondary flywheel intended to be coupled to a driven shaft, such as an input shaft of a gearbox. Torsion damping means are mounted between the primary flywheel and the secondary flywheel, said damping means having elastically deformable means and friction means for absorbing and damping vibrations and rotational acyclisms.

The patent application FR 2 969 730, in the name of the applicant discloses such a dual damping flywheel. The damping means comprise first damping means comprising three curved elastic members distributed circumferentially around the axis of the primary and secondary flywheels, and second damping means comprising six right elastic members distributed circumferentially around the aforementioned axis . These two damping means are coupled in series via an annular web and can filter noise and vibration at different engine speeds.

The first damping means are mounted between a primary mass of inertia and a primary cover, on the one hand, and the annular web, on the other hand. The second damping means are mounted between the annular web, on the one hand, and two guide washers, on the other hand, said guide washers being coupled in rotation to a secondary mass of inertia. A splined hub, intended to be coupled to the input shaft 3034482 2 of the gearbox, is fixed on the secondary mass of inertia and / or on at least one of the guide washers. The second damping means consist of two groups of elastic members, arranged in series by means of support members belonging to a phasing member, so that the elastic members of the two groups deform in phase with each other and the elastic forces generated by the second damping means are distributed circumferentially and homogeneously.

The phasing member comprises two annular plates fixed to each other and spaced apart axially so as to form between them a space for accommodating the elastic members, the support members being fixed axially between the two sheets. The rigid attachment of the hub to the secondary mass of inertia or to the guide washers can have a detrimental effect on the filtration performance and the wear of such a double damping flywheel. The invention aims in particular to provide a simple, effective and economical solution to this problem. For this purpose, it proposes a double damping flywheel 20 comprising a primary flywheel and a secondary flywheel, the secondary flywheel being able to pivot about an axis X with respect to the primary flywheel torsion damping means being mounted between the primary and secondary flywheels, the dual damping flywheel having an annular X-axis hub for coupling to a gearbox shaft, and a link belonging to the secondary flywheel and coupled in rotation along the axis X with the hub, characterized in that Y and Z axes are defined so that the X, Y and Z axes form an orthonormal coordinate system, the connecting member and the hub being coupled via a connection allowing a rotation along at least one of the Y and Z axes, the double damping flywheel 3034482 3 comprising elastic return means able to maintain the liaison body resting on the hub. In this way, the hub can pivot relative to the link member along the Y axis and / or the Y axis. Said link preferably prevents one or more of the following degrees of freedom: the following translation the X axis, the translation along the Y axis, the translation along the Z axis and the rotation along the X axis. Such a connection makes it possible in particular to compensate for any misalignment of the input shaft of the box. and hub relative to the connecting member, to improve filtration and reduce wear of the dual damping flywheel. The elastic return means may be able to hold the connecting member in abutment or in direct contact with the hub. According to one characteristic of the invention, said link may allow rotation along at least one of the Y and Z axes over an angular range of the order of 5 °, preferably of the order of 3 °. This value can be adjusted according to the clearance between the hub and the connecting member. In addition, the hub, or respectively the connecting member 20 comprises at least one recess, preferably at least three recesses, in which is engaged at least one connecting lug of the connecting member, respectively the hub, said connecting lug being adapted to be moved in said recess so as to allow a rotation along at least one of the Y and Z axes, said connecting lug being able to couple in rotation along the X axis the hub and the liaison body. In this case, each recess may have, in the YZ plane, a general V-shape and may comprise two oblique bearing surfaces with respect to the radial direction, the two bearing surfaces of the same recess departing from each other. one of the other radially outwardly, the corresponding connecting lug being able to bear on said bearing surfaces of the recess.

It will be noted that the terms "radial" and "axial" are defined with respect to the axis X. Moreover, each connecting lug may comprise a free end having a rounded surface or two oblique surfaces 5 with respect to the direction radial, the two oblique surfaces of the same connecting lug deviating from one another radially outwardly, said free end being engaged in the corresponding recess. The hub, or respectively the connecting member, may comprise a radial surface extending in the plane YZ, the tab of the connecting member, or respectively the hub, bearing on said radial surface. Said radial surface may be formed in at least one recess. In addition, said radial surface may be flat or curved so as to form a convex zone facing towards the connecting lug. The use of a convex zone makes it possible to facilitate the pivoting of the hub with respect to the connecting member, along the Y axis and / or along the Z axis. The elastic return means may be able to maintain the connecting lug resting on the radial surface. In particular, the elastic return means may comprise at least one spring washer capable of exerting a force along the axis X. The connecting member may be formed by a mass of secondary inertia 25, the connecting lugs may be formed of material with said secondary mass of inertia. The double damping flywheel may further comprise one or more of the following features: said link allows the rotation of each of the Y and Z axes of the hub relative to the connecting member; the relative rotation along the axis X of the hub relative to the connecting member is less than 0.5 °, such a rotation thus having a very low clearance, that is to say negligible, this rotation being due to the existence mounting clearance between the hub and the annular web, 5 - each bearing surface of the recess is inclined at an angle of between 10 and 45 ° relative to the radial direction, - each oblique surface of the leg of The connection is inclined at an angle of between 10 ° and 45 ° to the radial direction, the radial surface of the hub, or respectively of the connecting member, is provided in each recess, the radially inner periphery of the elastic washer comes to bear on a end of the hub, in particular on a frustoconical surface formed at said end of the hub, the double damping flywheel comprises a primary flywheel and a secondary flywheel, the secondary flywheel being able to pivot about the X axis relative to the primary flywheel, torsion damping means being located between the primary and secondary flywheels, the connecting member belonging to the secondary flywheel, the flywheel secondary inertia comprising an annular hub having an axis X, intended to be coupled to a gearbox shaft, a connecting member coupled in rotation along the axis X with the hub, Y and Z axes being defined in a manner the X, Y and Z axes form an orthonormal coordinate system, the connecting member and the hub being coupled via a connection permitting rotation along at least one of the Y and Z axes; the flywheel s the eccentric element comprises a secondary annular mass of inertia, said mass being fixed to the connecting member or integral with said connecting member, the radially outer periphery of the elastic washer is fixed, for example by riveting, at the radially inner periphery of the secondary mass of inertia, the primary flywheel comprises a primary mass of inertia and a primary cover, coupled in rotation with respect to one another and delimiting a volume internal housing for accommodating the torsion damping means, the torsion damping means comprise an annular web, at least one first circumferentially acting resilient member being circumferentially mounted between the primary mass of inertia and the annular web, the first elastic member is a helical compression spring, for example a curved spring, the torsion damping means comprise two rounds guide lobes coupled in rotation with respect to each other; - the guide washers are rotatably coupled, for example fixed by riveting, to the connecting member, the torsion damping means comprise less a second and a third elastic members with circumferential action, connected in series via a phasing member, the second and third elastic members are mounted in series, circumferentially between the annular web and the secondary flywheel, 20 particular between the annular web and the guide washers, - the second and third resilient members are helical compression springs, for example straight springs, - the second and third elastic members are located radially inside the first elastic member, The double damping flywheel comprises means for limiting the angular displacement, along the X axis, of the connecting member by means of with the annular web, the connecting member is located radially inside the annular web, the radially inner periphery of the annular web comprises at least one stop zone capable of cooperating with a complementary stop zone 3034482 7 at the radially outer periphery of the connecting member, so as to limit the angular displacement, along the axis X, of the connecting member with respect to the annular web, the phasing member comprises two plates fixed to one another; to the other 5 and located axially on either side of the annular web, - the phasing member comprises support members mounted axially between the two sheets, the second and third elastic members being able to bear on said bearing members, - the guide washers are situated axially on each side of the annular web and / or the phasing member, - the primary inertia mass and the primary cover are situated axially on the opposite side; Other than the annular web, the phasing member and / or the guide washers, the double damping flywheel comprises at least one sealing plate extending from one of the guide washers to the primary flywheel. , in particular from one of the guide washers to the primary inertia mass or to the primary cover, the double damping flywheel comprises a first sealing plate extending from one of the guide washers to the ground. of primary inertia, and a second sealing plate extending from the other guide ring to the primary cover, - the sealing plate, in particular the first sealing plate, is made of material with the return washer elastic. The invention will be better understood and other details, features and advantages of the invention will become apparent on reading the following description given by way of non-limiting example with reference to the accompanying drawings in which: FIGS. 1 to 6 FIG. 1 is an axial sectional view of the double damping flywheel, FIG. 2 is a perspective view, on the side of the gearbox, the double damping flywheel, - Figure 3 is an exploded view, in perspective, of a portion of the double damping flywheel, 5 - Figure 4 is a partially exploded view in perspective, of a portion of the double damping flywheel, - FIG. 5 is a perspective view of the hub, FIG. 6 is a perspective view of the spring return washer, FIGS. 7 and 8 show a second embodiment of the invention, in particular, FIG. figur 7 is an exploded perspective view of a portion of the double damping flywheel; FIG. 8 is a rear perspective view of the mass of inertia of the secondary flywheel; FIGS. FIG. 9 is an exploded view, in perspective, of a portion of the double damping flywheel; FIG. 10 is a perspective view from the front, of a part of the double damping flywheel, - Figure 11 is an axial sectional view of a subassembly of the double damping flywheel, - Figures 12 to 15 show a fourth embodiment of the invention, in FIG. 12 is a perspective view of the hub, FIG. 13 is a view in axial section of a portion of the double damping flywheel, FIG. 14 is a view in axial section of the hub, FIG. 15 is a detail view of part A of FIG. 13, FIG. 16 is a view in the neck. axial pe of a double damping flywheel according to a fifth embodiment of the invention. Figures 1 to 6 show a double damping flywheel (D.V.A.) for a motor vehicle 1 according to a first embodiment of the invention. It comprises a primary flywheel 2 intended to be coupled to a drive shaft, such as for example a crankshaft of an internal combustion engine of a motor vehicle, a secondary flywheel 3 intended to be coupled to a driven shaft, such as an input shaft of a gearbox. First and second torsion damping means are mounted between the primary flywheel 2 and the secondary flywheel 3. The primary flywheel 2 and the secondary flywheel 3 have general shapes of revolution and are substantially coaxial, X. Y and Z are defined as axes such that the X, Y and Z axes form an orthonormal coordinate system. The primary flywheel 2 is a flexible flywheel, comprising stacked sheet metal discs 4, and a primary mass mass of inertia 5, generally of revolution, surrounding the sheet metal disks 4. The disk assembly 4 of the primary flywheel 2 carries an inner hub 6 for attachment to the crankshaft. The primary flywheel 2 further comprises a primary cover 7 fixed, for example by welding, to the primary mass of inertia 5. The plates 4, the primary mass of inertia 5 and the cover 7 define an internal volume 8 housing the first and second damping means. The secondary flywheel 3 comprises in particular a mass 25 of secondary inertia 9. The primary flywheels 2 and secondary 3 are connected to one another via the first and second damping means, circumferential effect, connected in series and intended to absorb and dampen vibrations from the engine of the motor vehicle.

The first damping means comprise curved elastic members 10, preferably three curved elastic members 10 distributed circumferentially around the axis X. These curved elastic members 10 are intended to elastically couple the primary flywheel 2 with In particular, the elastic members 10 are mounted circumferentially between seats formed in the primary mass of inertia 5 and in the primary cover 7, and tabs 12 (FIGS. 3 and 4) extending radially towards the main body. from the outer periphery of the annular web 11. The second damping means comprise first and second guide rings 13, 14, secured in rotation with the secondary mass of inertia 9 by means of rivets 15, for example . The second damping means also comprise straight elastic members 16a, 16b, preferably three groups each comprising two straight elastic members 16a, 16b arranged in series. These three groups 16a, 16b are distributed circumferentially around the axis X.

Each group of two straight elastic members 16a, 16b in series extends circumferentially between two bearing seats 17 (FIG. 3) of the annular web 11. The straight elastic members 16a, 16b are intended to elastically couple the annular web 11 with the guiding washers 13, 14. For this purpose, the guide washers 13, 14 comprise arcuate slots 18 whose ends 19 form support seats for the straight elastic members 16a, 16b. So that the straight elastic members 16a, 16b of each group are arranged in series without friction, the second damping means comprise an annular phasing member 20, distinct 25 of the annular web. The phasing member 20 comprises two annular plates 21 located on either side of the annular web, and support members 22 fixed between said plates 21. Each support member 22 is circumferentially interposed between the two straight elastic members 16a, 16b consecutive of the same group, so that these two straight elastic members 16a, 16b consecutive are arranged in series.

The secondary flywheel 3 further comprises an annular connecting member 23, the radially outer periphery of which comprises abutment studs 24 extending radially outwards, engaged in notches 25 (FIG. 3) provided at the radially inner periphery. The abutment studs 24 are intended to bear against the circumferential ends of the notches 25, so as to limit the angular displacement between the connecting member 23 and the annular web 11. The angular movement thus authorized is for example between 10 and 20 °.

Legs 26, here eight in number, extend radially inwardly at the inner periphery of the connecting member 23, each tab 26 has a free end having two surfaces 27 oblique to the radial direction, the two oblique surfaces 27 of the same connecting lug 26 spacing from one another radially outwardly.

Each oblique surface 27 of the tab 26 is inclined at an angle of between 20 and 60 degrees to the radial direction. The connecting member 23 is fixed to the secondary mass of inertia 9 and the guide washers 13, 14 by means of the rivets 15. The secondary flywheel 3 further comprises a splined hub 28, 20 intended to be coupled to the input shaft of the gearbox. The hub 28 may be made of sintered steel and has at its radially outer periphery, recesses 29, here eight recesses 29, in which are engaged the ends of the tabs 26 of the connecting member 23. Each recess 29 has, in the YZ plane, a generally V-shaped or trapezoidal shape and comprises two oblique bearing surfaces 30 with respect to the radial direction, connected at their inner periphery by a plane surface 31 or in cylinder portion, the two bearing surfaces 30 of the same recess 29 deviating from one another radially outwardly. Each recess 29 thus opens radially outwards and radially towards the primary flywheel 2.

Each bearing surface 30 of the recess 29 is inclined at an angle of between 20 and 600 with respect to the radial direction. The oblique surfaces 27 of the corresponding connecting lug are able to bear against the oblique bearing surfaces 30 of the recess 29. Each recess 29 further comprises a planar radial surface 32 (see in particular FIG. 5). extending in the plane YZ and generally V-shaped or trapezoidal, the corresponding connecting lug 26 being able to bear on said radial surface 32.

The recesses 29 of the hub 28 and the tabs 26 of the connecting member 23 are dimensioned to allow rotation of the hub 28 relative to the connecting member 23 along the Y axis and the Z axis, while blocking, within the limits of the mounting gaps, the following degrees of freedom: translation along the X axis, translation along the Y axis, translation along the Z axis and rotation along the X axis The displacements of the hub 28 with respect to the connecting member 23 may be between 0 and 3 °, for the rotation along the Y axis, and between 0 and 3 °, for the rotation along the Z axis. In this way, the hub 28 can pivot relative to the connecting member 23 along the Y axis and / or along the Y axis. Such a connection makes it possible in particular to compensate for any misalignment of the input shaft. the gearbox and the hub 28 relative to the connecting member 23, in order to improve the filtration and to reduce the wear of the double flywheel mortiser 1.

The double damping flywheel 1 also comprises an elastic washer 33 able to exert a force along the X axis, the radially inner periphery of which bears on one end of the hub 28 which is turned away from the connecting member. 23, in particular on a frustoconical surface 34 (Figure 5) formed at said end 30 of the hub 28. This end may also include recesses 35 evenly distributed over the entire periphery. Such recesses make it possible in particular to reduce the weight of the hub 28, in particular when it is a sintered hub. The elastic washer 33 is fixed, at its radially external periphery, to the secondary inertia mass 9, to the connecting member 23 and to the guide washers 13, 14, via the rivets 15. The spring washer 33 thus maintains the legs 26 of the connecting member 23 bearing on the radial surfaces 32 of the hub 28, while allowing the hub 28 to pivot relative to the connecting member 23 along the Y and Z axes.

The double damping flywheel 1 further comprises a first and a second annular sealing plate 36, 37 (FIG. 1), fixed to the secondary flywheel 3 by means of the rivets 15. The first sealing plate 36 extends between the inner periphery of the guide washer 14 and the primary inertia mass 5 and / or the laminations 4. The second sealing plate 37 extends between the inner periphery of the guide washer 13 and the primary cover 7. According to a variant not shown, the sealing plate 37 and the spring washer 33 form a single piece. In operation, the torque is transmitted by the crankshaft 20 to the primary flywheel 2 which compresses the curved elastic members 10. The latter, bearing on the tabs 12, drive the web 11 and compress a first stage of straight elastic members 16a, 16b , then, via the phasing member 20, compress a second stage of straight elastic members 16b, 16a. This second stage in turn drives the secondary flywheel 3, in particular the hub 28 via the connecting member 23. It will be noted that, in this embodiment, the presence of the secondary mass of inertia 9 is optional. Its mass can also be reduced. This mass being low or zero, it is not necessary to balance the secondary flywheel 3.

FIGS. 7 and 8 show a second embodiment, which differs from that previously described with reference to FIGS. 1 to 6 in that the connecting member 23 and the secondary inertia mass 9 form a single piece. . The connecting lugs 26 5 are formed directly in the secondary mass of inertia 9. The operation of this double damping flywheel is identical to that described above. Figures 9 to 11 show a third embodiment, which differs from that described above with reference to Figures 1 to 6 in that the secondary mass of inertia 9 has a large mass. A subassembly 38 composed of, for example, the connecting member 23, the hub 28, the elastic washer 33, the mass 9 and the rivets 15 is then mounted, this subassembly 38 being illustrated. FIG. 11. This subassembly 38 can then be balanced in order to reduce its unbalance, before being mounted on another subassembly 39 comprising for example in particular the annular web 11, the guide washers 13, 14, the elastic members 16a, 16b and the phasing member 20.

In this embodiment, the two subassemblies can be assembled at the end of the assembly line whereas, in the case of the embodiment of FIGS. 1 to 6, the abovementioned elements of the double damping flywheel are assembled at the same time. time. FIGS. 12 to 15 show a fourth embodiment, which differs from that previously described with reference to FIGS. 1 to 6 in that the radial surfaces 32 of the hub 28 are not flat but curved so as to form convex zones turned to the corresponding connecting lugs 26. The vertices of the convex zones 32 may be situated on a circumference located radially outside the surfaces 31 and radially inside the radially outer periphery of the hub 28.

The use of a convex zone 32 facilitates the pivoting of the hub 28 with respect to the connecting member 23 along the Y axis and / or along the Z axis. FIG. 16 represents a fifth form. embodiment of the invention, which differs from that described with reference to Figures 1 to 6 in that the second damping means, comprising the straight elastic members 16a, 16b, the guide washers 13, 14 and the organ phasing 13, are replaced by pendular damping means. More particularly, the connecting member 23 is in the form of an annular support on which pendulum masses 40 are movably mounted by means of spacers 41 and rollers 42. Such pendular masses are known. of the prior art and will not be described in more detail. The connecting member 23 has tabs (similar to the tabs 12) extending radially at its outer periphery 15, serving as a support for the corresponding ends of the elastic members 10. The pivoting of the connecting member 23 around the X-axis causes the pendulum masses 40 to move relative to said connecting member 23. These masses 40 make it possible to improve the filtration of vibrations and rotational acyclisms.

Claims (11)

REVENDICATIONS1. Double damping flywheel comprising a primary flywheel (2) and a secondary flywheel (3), the secondary flywheel (3) being able to pivot about an axis X with respect to the flywheel primary (2), torsion damping means (10, 16a, 16b) being mounted between the primary (2) and secondary (3) flywheels, the double damping flywheel (1) having an annular hub (28). ) X-axis, to be coupled to a gear shaft, and a connecting member (23) belonging to the secondary flywheel (3) and coupled in rotation along the X axis with the hub (28). ), characterized in that Y and Z axes are defined so that the X, Y and Z axes form an orthonormal coordinate system, the connecting member (23) and the hub (28) being coupled via a link allowing a rotation along at least one of the Y and Z axes, the double damping flywheel having resilient return means capable of maintaining the connecting member (23) bears on the hub (28). 2. Dual damping flywheel (1) according to claim 1, characterized in that said connection allows a rotation along at least one of the Y and Z axes, over an angular range of about 5 °, preferably from order of 3 °. 3. Dual damping flywheel (1) according to claim 1 or 2, characterized in that the hub (28), or respectively the connecting member (23), comprises at least one recess (29), preferably at least three recesses (29), in which is engaged at least one connecting lug (26) of the connecting member (23), respectively of the hub (28), said connecting lug (26) being able to be moved in said recess (29) so as to allow a rotation along at least one of the Y and Z axes, said connecting lug (26) being able to couple in rotation along the X axis the hub (28) and the connecting member (23). 3034482 17 4. Dual damping flywheel (1) according to claim 3, characterized in that each recess (29) has, in the YZ plane, a generally V-shaped or trapezoidal shape and comprises two bearing surfaces (30) oblique to each other in the radial direction, the two bearing surfaces 5 (30) of the same recess (29) spacing radially outwardly from one another, the corresponding connecting lug (26) being adapted to abut on said bearing surfaces (30) of the recess (29). 5. Double damping flywheel (1) according to claim 3 or 4, characterized in that each connecting lug (26) has a free end 10 having a rounded surface or two surfaces (27) oblique to the radial direction, the two oblique surfaces (27) of the same connecting lug (26) deviating from one another radially outwards, said free end being engaged in the corresponding recess (29). 6. Double damping flywheel (1) according to one of claims 3 to 5, characterized in that the hub (28), or respectively the connecting member (23), has a radial surface (32) extending in the plane YZ, the lug (26) of the connecting member (23), or respectively of the hub (28) bearing on said radial surface (32). 7. Double damping flywheel (1) according to claim 6, characterized in that said radial surface (32) is formed in at least one recess (29). 8. Double damping flywheel (1) according to claim 6 or 7, characterized in that said radial surface (32) is flat or curved so as to form a convex zone facing the connecting lug (26). 25 9. Double damping flywheel (1) according to claim 3 and according to one of claims 6 to 8, characterized in that the elastic return means (33) are adapted to maintain the connecting lug (26) bearing on the radial surface (32). 10. Double damping flywheel (1) according to claim 9, characterized in that the elastic return means comprise at least one spring washer (33) adapted to exert a force along the X axis. 3034482 18 11. Double damping flywheel (1) according to one of claims 1 to 10, characterized in that the connecting member is formed by a secondary mass of inertia (9), the connecting lugs (26) being formed of material with said secondary mass of inertia (9). 5