FR2862730A1 - Vibration damper for motor vehicles torque transmission device, has two flywheels, and springs including leaves integrated at their one end to one flywheel and linked at their other end to another flywheel by links - Google Patents

Abstract

The damper has two flywheels (12, 22) mounted to rotate with respect to each other, and springs (42) mounted on the flywheel (22). The springs cooperate, due to elastic deformation, with links (40) mounted on the flywheel (12), to absorb and damp angular displacement between the flywheels. The springs have leaves integrated at their one end to the flywheel (22) and linked at their other end to the flywheel (12) by the links.

Description

between the input and output elements causes bending of

  blades that oppose this relative rotation, the maximum flexion of the blades being limited by stops fixed on either side of the blades on the corresponding input or output element.

  A disadvantage of this known device is the small angular clearance allowed between the input and output elements.

  Document EP-A-1 256 736 also discloses a torsion damper in which a friction disk is connected to a hub integral in rotation with a driven shaft by three groups of connecting means each comprising two elements. hinged together on the one hand and on the friction disk and on the hub respectively, on the other hand, and a circumferentially arranged straight spring mounted in windows of the guide washers of the torsion damper and acting on the articulated element on the friction disc. This structure is relatively complex and the maximum angular deflection is limited to relatively very low values. In addition, the springs of this damper are circumferentially disposed and are subjected to centrifugal forces in operation.

  The purpose of the invention is in particular to eliminate these disadvantages in a torsion damper.

  It relates to a torsion damper of the aforementioned type, comprising elastically deformable members not very sensitive to centrifugal forces and whose input and output elements can have a significant relative angular displacement, for example of the order of 40 to 60 degrees on either side of a median position.

  The invention also relates to a torsion damper of this type, which is simple, reliable and inexpensive.

  The invention also relates to a torsion damper of the aforementioned type, which solves the problem of resonance in a double damping flywheel at a certain rotational speed of the engine without the need for installation of a torque limiter.

  It proposes for this purpose a torsion damper for torque transmission device, in particular for a motor vehicle, comprising two coaxial input and output elements rotatably mounted relative to each other, and elastically deformable members carried by one of the input and output elements and cooperating by elastic deformation with pivoting members mounted on the other of the input and output elements for absorbing and damping the angular deflections between the input and output elements. output, characterized in that the elastically deformable members are integral flexion blades at their first ends of an input or output member and are connected at their second ends by links to the other input element or exit.

  A first advantage of the use of rods for connecting the bending blades to one of the input and output elements is a particularly large increase in the maximum possible angular displacement between the input and output elements, since the pivoting links are added to the flexion flexion flexion to determine the maximum angular deflection.

  It is thus possible to obtain a maximum angular displacement between the input and output elements which is for example about 40 to about 50 degrees on either side of a median position when the torsion damper comprises six sets of flexion blades, the blades being superimposed on each other in each set.

  According to another characteristic of the invention, this damper comprises means for limiting the elastic deformation and the stress of the bending blades, these limiting means including in particular for each set of bending blades, a convex curved surface carried by the bending blades. input member and extending from the attachment means of the first end of the set of bending blades in a direction oblique to a circumference centered on the axis of rotation of the input and output elements .

  This convex curved surface limits not only the elastic deformation and stress of the flexion blades but also the angular displacement between the input and output elements, in both directions of rotation.

  Advantageously, at the maximum value of the angular displacement in a direction of rotation, the rods are substantially in the extension of the flexion blades.

  As a result, in the vicinity of this maximum angular displacement, the stiffness of the elastic connection between the two input and output elements is very high and constitutes in itself an obstacle to increasing the angular displacement between the two elements. input and output elements in this direction of rotation.

  Thanks to this characteristic, the damper according to the invention replaces a torque limiter in a direction of rotation and effectively opposes the resonance phenomenon which otherwise occurred when passing through a speed of rotation less than the idle speed, in the case of a double damping flywheel.

  Advantageously, the aforementioned means of limitation also comprise, for each set of flexion blades, a bearing surface carried by the input element and extending along the set of flexion blades in its position. resting, radially outside this set of blades, to prevent or at least reduce its deformation by centrifugation.

  These limiting means may be either formed integrally with the input member or may be attached thereto and secured by means of screws, rivets, or the like.

  In a preferred embodiment of the invention, each rod is connected to a set of bending blades by a yoke attached to the second end of the set of bending blades and carrying a hinge axis of the link.

  Preferably, each set of bending blades is formed of a group of bending blades which are superimposed and fixed together at their first ends on the input element, at least one radially outer blade of this group being connected by its second end to the corresponding link.

  In this embodiment, the connecting yoke between a link and a set of bending blades is attached by one or more rivets to the second end of the radially outer flexion blade of the flexion blade assembly and at least one Another flexion blade located inside the radially outer comprises at its second end a light or a notch for receiving the head of the aforementioned rivets.

  In general, the damper according to the invention is of simple structure, it is particularly reliable and is also less expensive than the corresponding devices of the prior art.

  The invention will be better understood and other characteristics, details and advantages thereof will appear more clearly on reading the description which follows, given by way of example with reference to the accompanying drawings, in which: FIG. schematic view in axial section of a double damping flywheel according to the invention and an associated clutch; Figure 2 is a schematic elevational view of the dual damping flywheel according to the invention; Figures 3 and 4 are schematic half elevational views of this double damping flywheel, in positions of maximum angular movement; FIG. 5 is a graph showing the variation of the elastic force developed by the set of flexion blades as a function of the angular displacement between the input and output elements; Figure 6 is a schematic axial sectional view of an alternative embodiment; - Figures 7 and 8 are schematic perspective views of two embodiments of the rods; - Figures 9 and 10 are partial schematic views in axial section and elevation of another embodiment of the invention; - Figures 11 to 16 are partial schematic views in axial section and elevation of other embodiments of the invention.

  In the exemplary embodiment shown in FIG. 1, the torsion damper 10 according to the invention is part of a double damping flywheel which ensures a transmission of torque between a drive shaft (not shown) which is the crankshaft of a internal combustion engine of a motor vehicle, and a driven shaft which is for example the input shaft of a gearbox connected to the double damping flywheel by a clutch E. This double damping flywheel comprises a primary flywheel 12 , fixed in the vicinity of its radially inner periphery on the end of the drive shaft by screws 14 and carrying at its radially outer periphery a starter ring 16.

  The radially inner periphery of the primary flywheel 12 comprises a cylindrical appendage 18 for supporting a bearing 20 such as a ball bearing for centering and guiding in rotation a secondary flywheel 22 which is coaxial with the primary flywheel 12 and which forms the reaction plate of the coupling clutch E to the driven shaft.

  The clutch E comprises, in a conventional manner, a pressure plate 24 axially displaceable with respect to the secondary flywheel 22 and biased towards the latter in axial translation by an annular diaphragm 26 which bears on a clutch cover 28 fixed at its periphery radially external to the radially outer periphery of the secondary flywheel 22 by screws 30.

  The radial face of the secondary flywheel 22 turned away from the primary flywheel 12 forms a friction surface cooperating with the friction linings of a clutch disc 32 which is connected to the driven shaft by a cylindrical hub 36 in which is engaged the end of the driven shaft and whose inner surface has splines cooperating with corresponding splines of this end of the driven shaft for driving in rotation of this shaft about an axis 38 which is the axis common drive shaft, flywheels 12 and 22, the clutch E and the driven shaft.

  The structure and operation of the clutch E are well known to those skilled in the art and will not be described here in more detail.

  According to the invention, the two flywheels 12 and 22 are connected in rotation by a torsion damper which comprises, as best seen in FIG. 2, a set of rods 40 and groups of flexion blades 42, some of which are worn. by one of the flywheels 12, 22 and the others by the other flywheels 12, 22, the rods and groups or sets of bending blades being six in the example shown.

  In this embodiment, the links 40 are carried by the secondary flywheel 22 which is the output member of the torsion damper and the sets of flexion blades 42 by the primary flywheel 12, which forms the element of the damper, but this arrangement could be reversed, the rods being carried by the input member and the sets of bending blades by the output member of the torsion damper.

  In FIGS. 1 and 2, the links 40 are mounted articulated about axes 44 parallel to the axis of rotation 38 on the secondary flywheel 22 by their radially inner ends, their opposite ends being articulated on axes 46 parallel to the axis of rotation and carried by yokes 48 which are fixed by screws, rivets or the like 50 on the second ends of the sets of flexion blades 42 whose first ends are fixed by rivets 52 on parts 54 of deformation limitation which are themselves fixed by screws, rivets 56 or the like on the primary flywheel 12.

  The parts 54 have a convexly shaped annular surface 58 which extends radially inside the bending blade assemblies 42 in an oblique direction oriented radially inwardly with respect to a circumference centered on the axis of rotation. and passing close to the attachment points 52 of the sets of flexion blades 42. This annular surface 58 of each piece 54 limits the elastic deformation in bending and the stresses of each set of blades 42 in both directions of rotation between the two wheels inertia.

  The links 40 and the sets of flexion blades 42 are shown in rest positions in FIG. 2 and in positions of maximum angular deflection in FIGS. 3 and 4, for example in the forward direction in FIG. 3 and in the direction of FIG. opposite rotation (retro direction) in figure 4.

  In the rest position shown in FIG. 2, the rods 40 are substantially radial and the sets of flexion blades 42 occupy the position of a cord on a circumference centered on the axis of rotation and passing through their attachment points 52 on the annular piece 54 and their attachment points 50 on the yokes at the end of the rods.

  In the position of maximum angular displacement in the direct direction shown in Figure 3, each rod 40 forms an acute angle with the set of corresponding bending blades which is flexed bearing on the annular part 54 associated.

  The angular displacement between the rest position and that shown in Figure 3 is of the order of 50 to 55 degrees for example.

  In the position of maximum angular displacement in the retro direction shown in FIG. 4, the sets of flexion blades are bent in abutment on the annular pieces 54 and the links 40 are substantially in the extension of the sets of flexion blades 42.

  The maximum angular deflection in the retro direction from the rest position of the rods 40 is of the order of 40 degrees for example.

  The stiffness of the elastic connection formed by the links 40 and the sets of flexion blades 42 between the flywheels increases progressively with the angular deflection and is different in the two directions of rotation, as schematically represented in FIG. 5, which is a graph representing the variation of the elastic force F between the flywheels according to the angular displacement alpha between these flywheels.

  In general, the stiffness of this elastic connection varies with the deformation of the flexion blades, their support on the means of limiting deformation, and the direction of application of the force by the rod.

  In the direct direction corresponding to the IF part of the curve, the stiffness which is represented by the slope of the curve increases progressively between the rest position corresponding to the point O and the maximum angular displacement corresponding to the point D1.

  In the opposite direction, the stiffness corresponding to the slope of the part F2 of the curve increases progressively as a function of the angular deflection, faster than for the part FI of the curve and reaches a high value at the point D2 of maximum angular deflection.

  This is due to the fact that in the vicinity of the maximum angular deflection point in the retro direction, the force to be exerted on the set of flexion blades 42 to flex it further becomes higher and higher for a unitary increase in angular deflection.

  This elastic force effectively opposes the development of a resonance phenomenon in the double damping flywheel, which avoids providing a torque limiter in this torsion damper or at the level of the secondary flywheel 22.

  In a variant embodiment, a tension or compression spring is associated with each link assembly / set of bending blades, this spring being mounted between one of the flywheels and the link assembly / set of bending blades, as can be seen in FIG. will see it in detail in the following.

  In the embodiment shown in FIGS. 1 to 4, means are provided for limiting the elastic deformation of the sets of flexion blades 42 by centrifugation, these means comprising a bearing surface 60 which is radially outside each set of flexion blades 42 and which is fixed on the primary flywheel 12. This fixation is performed by welding points in the example shown.

  Each bearing surface 60 extends substantially between the attachment points 50 and 52 of the flexion blade assembly 42 on a yoke 48 and an annular piece 54, respectively.

  It will also be noted that the stiffness of the elastic connection between the flywheels increases as a function of the speed of rotation, because of the centrifugation effect of the mass of the link, means of attachment between link and set of flexion blades and of the set of flexion blades.

  Alternatively, the bearing surfaces 58 and 60 of the flexion blade assemblies 42 could be carried by one and the same part for each set of flexion blades 42. In another variant, it is possible to provide on the element of 12 a radial abutment 61 for each set of flexion blades 42, as shown in Figure 2.

  In the example shown, each set of flexion blades 42 is formed by the superposition of several bending blades 62 which are substantially identical, these bending blades 62 being fastened together by a rivet 52 on the aforementioned annular piece 54 and only the 62 radially outer blade being fixed by one or more rivets 50 on the yoke 48. This yoke can also be made in one piece with the radially outer blade 62.

  The other bending blades which are radially inward relative to that fixed to the yoke 48, terminate near the rivet or rivets 50, so as not to interfere with these rivets in the maximum bending position shown in FIGS. Figures 3 and 4.

  The length and thickness of the other blades may vary depending on the desired elastic characteristics of the assembly. Some or all of the bending blades may be of composite material, of the mineral or organic fiber matrix type and plastic or rubber binder.

  The contacting surfaces of the bending blades 62 may be treated or coated with any material suitable for reducing wear in operation. The friction between the superimposed blades during the bending of the blade assembly 42 contributes to the damping of the angular deflections between the flywheels.

  It can also be provided that an end stop is formed at the maximum angular displacement by contact between each rod and a set of adjacent bending blades (Figure 3). This stop may be elastic for example because of the nature of the end of the set of bending blades or by mounting an elastic element on this end.

  One or more intermediate blades of a material to control friction and wear can be placed between the flexion blades.

  In more detail in the embodiment of FIG. 2, the bending blades 62 are of generally elongated rectangular shape and have, for example, a useful bending length of 80 millimeters for a width of 11.5 millimeters and a thickness of 1 millimeter. In this example, they are made of spring steel.

  In the variant embodiment of FIG. 6, the double damping flywheel is of the same type as that of FIGS. 1 to 4, but the steering and centering bearing of the secondary flywheel 22 on the primary flywheel 12 is replaced by a sliding bearing 64 for example radially outwardly open U-shaped section which receives the inner peripheral portion of the secondary flywheel 22. The bearing 64 is carried by two rings 66, 68 fixed on the primary flywheel and on the drive shaft by the screws 14 and by rivets 70, these rings 66, 68 having radially outer annular peripheral rims 72, 74 which extend in planes perpendicular to the axis 38 and between which is housed the sliding bearing 64.

  In FIGS. 7 and 8, the link between the link 40 and a flexion blade 62 is made by hooking a T-end 76 of the link on two curved tabs 78 of the flexion blade 62.

  In Figure 7, the end 76 of the rod is directly in contact with the curved tabs 78 of the flexion blade.

  In FIG. 8, the end 76 of the rod forms two axes parallel to the axis 38 and on which are rotatably mounted two rings 80 of low friction material, which are received in the curved portions of the legs 78 of the flexion blade.

  In the variant embodiment of FIGS. 9 and 10, which represent a double damping flywheel, the damper is of the same type as that of FIGS. 1 to 4, but the steering and centering bearing of the secondary flywheel 22 on the primary flywheel 12 is replaced by a plain bearing for example with two diameters of the stamped hub type, which comprises a radial face 82 applied on the primary flywheel 12 and two cylindrical faces 84, 86 radially and axially offset, supporting two corresponding cylindrical surfaces of the secondary flywheel 22, and an outer radial rim 88 of axial retention of the secondary flywheel 22. The cylindrical faces 84, 86 of the bearing are supported by an annular spacer 90 and a washer 92, respectively, which are fixed with the radial face 82 of the bearing on the bearing. input element 12 by the screws 14.

  In this embodiment, the rods comprise a first portion 94 formed by a rod articulated on the secondary flywheel 22, and a second portion 96 extending in the extension of the rod 94 between the latter and the blade assembly. corresponding bending 42, this second portion 96 being formed of two parallel sheet plates, fixed by rivets 98 on two opposite faces of the rod 94 of the rod, and articulated at their radially outer ends by a bearing bearing 100 on the second end of the bending blades 62. The bearing 100 is fixed on one end of a radially outer bending blade 62 of the bending blade assembly 42, in order to avoid any additional bending stress at the end of the blade.

  More specifically, the support bearing 100 comprises a cylindrical body 102 fixed by a rivet 104 on the end of the outer flexion blade 62, and an axis 106 housed in the body 102, this axis 106 joining the two plates. of sheet metal of the second portion 96 at their radially outer end.

  In the variant embodiment of FIGS. 11 and 12, which also represent a double damping flywheel, compression springs 108 are associated with the bending blades and links and are mounted substantially radially between the second ends of the flexion blades 62 and seats 110 of support formed by an annular element 112 of the primary flywheel 12, the springs 108 still remaining oriented substantially radially, regardless of the angular deflections between the flywheels 12, 22. In this embodiment, the rods are each formed of two parallel arms 114 which are connected at their ends and between which the springs 108 extend, so that the rods can be oriented obliquely with respect to the springs 108 depending on the angular deflections between the wheels 12, 22.

  The radially outer ends of the springs 108 bear on caps 116 interposed between these springs 108 and the second ends of the bending blades 62, these caps 116 having circumferential arms 118 which extend on either side of the springs 108. and which come into elastic support, at the end of angular deflection, on abutments 120 formed on the annular element 112 secured to the primary flywheel 12.

  The seats 110 bearing the radially inner ends of the springs 108 and the abutments 120 are formed by cut edges of the annular element 112 which is housed between the flywheels 12, 22 and fixed, for example by rivets 122 at the steering wheel. primary 12, the rivets having a spacer substantially in their middle and disposed between the flywheel 12 and the annular element 112, the spacer for axially positioning the annular element 112 relative to the flywheel 12.

  In the position of maximum angular displacement between the flywheels, the circumferential arms 118 of the caps 116 which cap the springs 108, apply to the stops 120 of the annular element 112 and oppose by elastic deformation at the end of the angular deflection . This avoids a torque limiter in the double damping flywheel.

  Moreover, the bending blades 62 are folded over themselves in their middle and their superposed free ends are fixed by rivets on the annular element 112, while their bent part surrounds an axis 115 of articulation of the radially outer ends of the connecting rods 114.

  The variant embodiment of FIGS. 13 and 14 concerns a torsion damper whose input element is a clutch friction disc 124 and whose output element is a hub 126 integral in rotation with a driven shaft 128 , which is the input shaft of a gearbox.

  The disc 124 is fixed to an annular piece 130 supported and guided in rotation on the hub 128, by means of rivets 132 which connect the annular piece 130 to a washer 134 arranged at the end of the hub 126 opposite the flywheel. inertia 12 driven by the motor shaft. The washer 134 is, at its inner periphery, associated by friction means 136 to a washer 138 fixed on the aforementioned end of the hub 126.

  The radially outer portion of the washer 134 has a cylindrical rim 140 which surrounds bending blades 62 fixed at one end by rivets to a cylindrical rim 142 of the annular piece 130. The other end of the blades 62 is articulated around an axis 144 on the radially outer end of a rod whose radially inner end is articulated about an axis 146 on the hub 126.

  Each link is formed of two parallel sheet metal plates 148 applied on the ends of the hub 126. The bending blades 62 are in this embodiment, bent in a U-shape, their free ends being superposed and riveted on the flange 142 of the annular piece 130 while that their bent part surrounds the axis 144.

  Straight springs 150 are mounted radially between cap members 152 located under the axes 144 and plane seats formed by the annular piece 130.

  In operation, during angular deflections between the flywheel 12 and the hub 126, the right springs 150 are compressed and remain oriented radially. The bending blades 62 are bent towards the axis of rotation 38, their bent ends on the axes 144 are drawn towards the axis of rotation 38 by the rods 148 which are then obliquely oriented as shown in dashed lines in FIG. 13 .

  The cylindrical rim 142 of the annular piece 130 has curved portions towards the axis 38, which limit the bending of the blades 62. The cylindrical rim 140 of the washer 134, which surrounds the blades 62, limits the radial outward movement by centrifugation, bent parts of the blades 62 and caps 152. For the rest, conventionally, the wheel 12 forms the tray of

  reaction of the clutch, on which the friction lining of the disk 124 are supported by a pressure plate 154 itself biased by an annular diaphragm 156 mounted on a cover 158 integral with the flywheel 12.

  The variant embodiment of FIGS. 15 and 16 relates to a double damping flywheel and differs from those of FIGS. 11 and 12 firstly in that the springs 108 mounted radially between the caps 116 and the seats 110 are three in number per cap. and by seat and are parallel and juxtaposed in the circumferential direction. This makes it possible to increase the stiffness of the force developed by these springs without increasing the axial size of the torsion damper, as can be seen in FIGS. 15 and 16.

  In addition, the torsion damper comprises circumferential springs 160 which are conventionally mounted in windows of two guide washers 162 secured to the primary flywheel 12, and in windows of an annular web 164 which is associated by means friction piece forming a torque limiter to a washer 166 integral with the secondary flywheel 22. As shown in FIG. 16, the washer 166 is fixed to the secondary flywheel 22 by the hinge pins of the rods 114. These are formed of two plates of sheet metal which extend on either side of the springs 108 to be able to orient obliquely with respect to the springs 108 during the angular movements of the two wheels relative to each other.

  In the example shown, the torsion damper comprises two circumferential springs 160 (or two groups of circumferential springs) diametrically opposed, the rods and the radial springs 108 being arranged between these springs or groups of diametrically opposed springs.

  Many variants can be made to the means described and shown which are used for the attachment of the links on the flexion blades, and for the attachment of the flexion blades on these means and on the input element of the damper, without departing from the scope of the invention defined by the following claims.

Claims (1)

17 CLAIMS   1. Torsional damper for a torque transmission device, in particular for a motor vehicle, comprising two coaxial input and output elements (12, 22) rotatably mounted relative to one another, members (42) ) elastically deformable carried by one of the input and output elements (12, 22) and cooperating by elastic deformation with pivoting members mounted on the other input and output elements (12, 22) to absorb and damping the angular deflections between the input and output elements (12, 22), characterized in that the elastically deformable members (42) comprise bending blades (62) integral at their first ends with an element of input or output (12, 22) and connected at their second ends by links (40) to the other input or output element (12, 22).   Shock absorber according to Claim 1, characterized in that the bending blades (62) occupy at rest the position of a rope on a circumference centered on the axis of rotation (38) of the input and output elements ( 12, 22).   3. Shock absorber according to claim 1 or 2, characterized in that the links (40) extend in the rest position in a substantially radial direction relative to the axis of rotation (38) of the input and output elements. (12, 22).   Shock absorber according to one of the preceding claims, characterized in that the connecting rods (40) are articulated on the output element (22) and on the second ends of the flexion blades (62) about axes (44, 46) which are parallel to the axis of rotation (38) of the two input and output elements (12, 22).   5. Shock absorber according to one of claims 1 to 4, characterized in that the rods (40) are hooked on the second ends of the flexion blades (62).   6. Shock absorber according to one of the preceding claims, characterized in that it comprises means (54, 60) for limiting the elastic deformation of the flexion blades (62).   Shock absorber according to Claim 6, characterized in that the limiting means comprise convex curved surfaces (58) carried by the input element (12) and extending from the means (52) of fixing the first ends of the bending blades (62) in a direction oblique to a circumference centered on the axis of rotation (38).   Shock absorber according to claim 7, characterized in that said convex curved surfaces (58) also limit the angular displacement between the input and output elements (12, 22) in both directions of rotation.   9. Damper according to claim 8, characterized in that, at the maximum value of the angular displacement in a direction of rotation, the rods (40) are substantially in the extension of the bending blades (62), and at the maximum value of angular deflection in the other direction of rotation, the links (40) are at an acute angle with the flexion blades (62).   Damper according to one of Claims 6 to 9, characterized in that the maximum angular deflection values between the input and output elements (12, 22) are in one and the other direction. of rotation between the input and output elements (12, 22) are about 40 to 50 on either side of a median position.   Shock absorber according to one of Claims 6 to 9, characterized in that the maximum angular deflection values between the input and output elements (12, 22) are substantially different in the one and the other direction. rotation between the input and output elements (12, 22) and are about 50 to 55 in the forward direction and about 40 in the retro direction with respect to a middle position.   Damper according to one of claims 6 to 11, characterized in that said limiting means comprise a bearing surface (60) carried by the input element (12) and extending along the blades of bending (62) radially outwardly of said bending blades (62) to reduce their elastic deformation by centrifugation, said limiting means being fixed to the input member (12) by screws, rivets (56); ), soldering points, or the like.   13. Shock absorber according to one of claims 1 to 4 and 6 to 12, characterized in that each rod (40) is connected to at least one flexion plate (42) by a yoke (48) fixed on the second end of bending blades (62) and carrying an axis (46) for articulating the rod (40), at least one radially outer of the flexion blades being connected by its second end to a link (40), the second end the radially outer bending blade is fixed by at least one rivet (50) to the yoke (48) and the bending blades (62) located radially inside the bending blade (62) ending at a distance from the rivet (50).   14. Damper according to claim 13, characterized in that at least one of the bending blades (62) is made of composite material.   15. Damper according to claim 13 or 14, characterized in that at least one intermediate blade, in material for controlling friction and wear, is inserted between two bending blades (62).   16. Damper according to one of the preceding claims, characterized in that in a position of maximum angular deflection, the second ends of the bending blades (62) abut on adjacent rods (40) via elastic means .   17. Shock absorber according to one of the preceding claims, characterized in that each link (40) comprises at least one portion (96) connected to a set of corresponding bending blades (42) and formed of two parallel plate plates, articulated at their radially outer ends by a bearing (100) bearing on the second end of the flexion blades (62).   Shock absorber according to one of the preceding claims, characterized in that compression springs (108, 150) are associated with the bending blades and are mounted substantially radially between the second ends of the bending blades (62) and the seats. support (110) integral with the input element (12), said springs (108, 150) remaining oriented substantially radially regardless of the angular deflections between the input and output elements (12, 22).   Shock absorber according to Claim 18, characterized in that the rods can orient obliquely with respect to the springs (108, 150) as a function of the angular deflections between the input and output elements (12, 22) and comprise two parallel arms (114, 148) connected at their ends and between which the springs (108, 150) extend.   20. Shock absorber according to claim 18 or 19, characterized in that the radially outer ends of the springs (108, 150) bear on caps (116) interposed between these springs (108, 150) and the joints of the flexion blades. (62) on the rods, these caps (116) having circumferential arms (118) which extend on either side of the springs (108) and which bear elastically, at the end of angular deflection, on stops (120) integral with the input member (12).   Shock absorber according to one of Claims 18 to 20, characterized in that the bearing seats (110) of the radially inner ends of the springs (108) are formed by an annular piece (112) arranged between the input elements. and outlet (12, 22) and fixed, for example by rivets, to the input element (12).   22. Shock absorber according to claim 20 or claim 21, characterized in that said annular piece (112) also bears the bearing stops (120) for the end of travel of the circumferential arms (118) of the caps (116).   23. Shock absorber according to one of claims 18 to 22, characterized in that it also comprises circumferentially disposed springs (160) mounted in windows of two guide washers (162) integral with the input element. (12) and an annular web (164) connected to the output member (22).   Shock absorber according to Claim 23, characterized in that the radial springs (108) extend between the circumferential springs (160).   25. Damper according to claim 23 or 24, characterized in that it comprises two springs or two groups of springs (160) circumferential diametrically opposed.   26. Shock absorber according to one of the preceding claims, characterized in that it connects in rotation the two flywheels (12, 22) of a double damping flywheel.   27. Shock absorber according to one of the preceding claims, characterized in that it connects a disc (124) of clutch friction to a shaft (128) input of the transmission.