FR3008151A1 - VIBRATION ABSORPTION DEVICE - Google Patents

Abstract

The present invention relates to a vibration absorption device for a motor vehicle transmission, said device having an axis X of rotation and comprising a support (10), two adjacent flyweights (39) and a synchronizer (40) associated with said weights, the flyweights and the synchronizer being freely movable on the support, and being able to be arranged according to a set of positions, called "external radial stop positions", in which the flyweights and the synchronizer can no longer be moved to the outside following a radial direction, the synchronizer being interposed between the flyweights so as to prevent any contact between said flyweights, and so as to be in linear and / or point contact with said flyweights regardless of the radial stop position considered external.

Description

TECHNICAL FIELD The present invention relates to a vibration absorbing device for the transmission of a motor vehicle. STATE OF THE ART In a motor vehicle transmission, in order to filter the vibrations due to the acyclisms caused by the explosions in the engine cylinders, a damping device is conventionally used, associated with a clutch that selectively connects the engine to the gearbox. speeds. This clutch can be a friction clutch for a motor vehicle with a manual transmission, or be arranged in a hydrokinetic coupling device for an automatic transmission vehicle, as a locking clutch. With this damping device, generally in the form of a one-piece flywheel, a flexible flywheel, or a vibration absorption device, the effect of the engine vibrations which would otherwise be transmitted through the gearbox and cause shocks, noises or noise particularly undesirable for the occupants of the motor vehicle. The search for obtaining an ever more efficient filtration led to integrate a pendulum oscillator vibration absorption devices.

In particular, oscillating oscillators are known in the prior art, including flyweights able to oscillate freely in a plane orthogonal to the transmission axis. The pendulum oscillators of the prior art conventionally consist of a complicated assembly of parts of complex shapes, difficult to machine. The costs to manufacture or mount such oscillators are high.

In addition, a trend in the automotive market is to reduce the number of cylinders of the engine while increasing the power developed by the engine. The power developed by each cylinder is thus increased, which amplifies the motor acyclisms and generates a vibratory spectrum that the aforementioned damping devices filter with difficulty.

This results in additional nuisances, including noise, particularly undesirable. FR 2 858 671 discloses a vibration absorption device comprising cylindrical weights.

JP 7-280037 discloses a vibration absorbing device comprising a chain of cylindrical weights interconnected by synchronizers. In this device, the synchronizers have curved lateral surfaces corresponding to the surfaces of the weights with which they are in close contact. However, for optimum efficiency of the device of JP 7-280037, the weights must be machined with low manufacturing tolerances, in particular to ensure close contact between weights and synchronizers. The manufacture and assembly of such a device is therefore expensive. There is a need for a vibration absorbing device consisting of pieces of simple geometry, easy assembly and having a limited manufacturing cost. The object of the invention is to meet this need. SUMMARY OF THE INVENTION The object of the invention is achieved by means of a vibration absorption device intended for a motor vehicle transmission, said device having an axis X of rotation and comprising a support, two adjacent flyweights and a synchronizer associated with said weights, the flyweights and the synchronizer being freely movable on the support, and can be arranged according to a set of positions, called "external radial stop positions", in which the flyweights and the synchronizer can no longer be moved outward in a radial direction. According to a first main aspect of the invention, the synchronizer is interposed between the flyweights so as to prevent any contact between said flyweights, and so as to be in linear and / or point contact with said flyweights regardless of the stop position outer radial considered. During a rotation of the device according to the invention, the movements of the flyweights 30 can be coordinated by the action of the synchronizer which can roll on said flyweights. The inventors have thus been able to observe that the overall movement of the weights and the synchronizer effectively damps the vibrations of the motor transmitted to the device. In addition, the contact between the weights and the synchronizer being linear and / or punctual, the weights and / or the synchronizer can be easily manufactured in simple geometric shapes. A device according to the invention allows high manufacturing tolerances and is advantageously less expensive to manufacture and simplified assembly. Preferably, a vibration absorption device according to the invention comprises a crown of X-axis flyweights, a ring of synchronizers, of X axis, the flyweights and synchronizers being freely movable on the support and being able to be arranged in positions, called "external radial stop positions", in which the flyweights and the synchronizers can no longer be displaced outwards in the radial direction, each pair of two adjacent flyweights being associated with a synchronizer interposed between said two flyweights adjacent to prevent contact between said two adjacent flyweights and to be linear and / or point contact with said two adjacent flyweights, regardless of the outer radial stop position considered. Advantageously, during the absorption of the vibrations, the oscillations of the crown of flyweights and the ring of synchronizers are coordinated, each synchronizer of the ring of synchronizers can in particular roll on a pair of adjacent flyweights of the crown of flyweights. These coordinated oscillations result in efficient filtration and absorption of vibrations. A vibration absorption device according to the invention may also comprise one or more of the following optional features, according to all the possible combinations: the synchronizer (s) are radially internal (s) with respect to the associated adjacent flyweights. - The synchronizer (s) and / or at least one of the flyweights are in the form of a ball or roll in the form of a cylinder or barrel, one or more of the lateral faces of the roll being optionally curved. The ratio of the diameter of at least one of the two adjacent flyweights, preferably the two adjacent flyweights, to the diameter of the associated synchronizer is greater than 1 and / or less than 5, the diameters being measured in a median plane orthogonal to the X axis. - The device comprises a bearing surface guiding the displacement of said flyweights between said outer radial abutment positions, and / or a bearing surface guiding the displacement of said synchronizer (s) between a set of positions of internal radial stop in which the synchronizer (s) can no longer be moved inward in a radial direction. Such bearing surfaces make it possible to limit the radial and / or orthoradial deflection of the flyweights and / or the synchronizers at the low speeds of rotation of the vibration absorption device (less than 200 revolutions / minute) and to obtain a filtration of the effective vibration when the absorption device subsequently undergoes acceleration. - One or more of said bearing surfaces is (are) defined by a bearing surface of the support oriented radially outwardly and / or radially inwardly. - At least one of said bearing surfaces is defined by a surface of a support ring cooperating preferably with a peripheral surface of the weights and / or synchronizer (s), or by a buttonhole. This buttonhole may in particular cooperate with a feeder pin and / or a synchronizer pin. - Said bearing surface has a corrugated profile. - The device comprises a separator rigidly secured to the support, interposed between two adjacent weights, and / or between two adjacent synchronizers, so as to limit the orthoradial and / or radial displacements of said weights and / or said synchronizers. According to other main aspects of the invention, the synchronizer and / or the flyweights respectively have a cylindrical shape, the lateral faces of the synchronizer and / or the flyweights being curved, and / or the synchronizer and / or the flyweights have shapes which are not of revolution, and / or - the device comprises a separator integral with the support and interposed between the two adjacent flyweights, and / or two adjacent synchronizers respectively, and being shaped to limit radial displacements to the outside and inwards flyweights and / or synchronizers respectively. the device comprises a bearing surface defined by a buttonhole and guiding the displacement of said weights between said outer radial abutment positions and / or a bearing surface defined by a buttonhole and guiding the movement of the synchronizer between a set of positions of internal radial stop in which the synchronizer can no longer be moved inward in a radial direction. The invention also relates to a transmission of a motor vehicle, in particular selected from a friction clutch and a hydrokinetic converter, said transmission comprising a vibration absorption device according to the invention. The invention finally relates to a motor vehicle equipped with a transmission according to the invention. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood on reading the following detailed description and on examining the appended drawing, in which: FIG. 1 represents, in axial view, a device for absorbing vibrations according to a first embodiment of the invention, in which a flange has been removed, - Figure 2 shows in a section along the plane (II), a part of the device according to the first embodiment shown in Figure 1, - FIG. 3 represents a partial and enlarged view of the absorption device of FIG. 1; FIGS. 4 and 5 show a vibration absorption device according to a second embodiment of the invention; FIG. a particular arrangement of the flywheel and synchronizer crowns; FIG. 7 shows the flywheel and synchronizer crowns of FIG. 6 mounted in the support of a vibratory absorption device; According to a third embodiment, FIG. 8, FIG. 9, respectively, shows in section along an axial median plane, a vibration absorption device according to a fourth, a fifth, respectively, embodiment, FIGS. 14 to 14 show in section along the plane (JJ) a device according to the invention, having alternative embodiments, and - Figure 15 shows in axial view a vibration absorbing device according to a variant of the second embodiment. In the different figures, identical or similar members have been identified with the same reference.

Definitions By convention, a "radial" orientation is directed orthogonally to an axis and passes through this axis. The axis defines the "axial" orientation. The "orthoradial" orientation is orthogonal to both the axis and the radial orientation. Unless otherwise indicated, the axis is the X axis of rotation of the vibration absorbing device holder.

By plane or section "axial" or "radial" means a plane or section of which a normal vector is collinear with an axis or a radial orientation. By plane or "longitudinal" section, is meant a plane or a section containing the axis. Unless otherwise indicated, this axis is the X axis of rotation. The terms "radially inner" and "radially outer" define positions relative to the X axis: a radially inner object is closer to the X axis than a radially outer object. "Inward" and "outward" orientations correspond to orientations of a surface towards the X axis or opposite to the X axis. The normal to this surface is not necessarily radial.

The term "external or internal radial abutment position" means any position in which an object, for example a flyweight or a synchronizer, can no longer be moved radially outwards or inwards, respectively in a radial direction. A radial abutment position is not necessarily a locking position, certain radial abutment positions permitting displacement in an axial or orthoradial direction, or more generally in a direction which comprises at least one component which is not radial. Unless otherwise indicated, a thickness is the largest dimension measured along the X axis.

A moving object that is not mechanically driven by another object, for example by a motor, is conventionally called "freely mobile". "With one (or two)" or "comprising one (or two)" means "having at least one (or at least two, respectively)", unless otherwise indicated. "Defining one" means "defining at least one", unless otherwise indicated.

Detailed Description The examples illustrated by the drawing are preferred embodiments and are provided for illustrative purposes only. The invention is therefore not limited to these embodiments. The vibration absorbing device 5 of Figure 1 comprises a support 10 consisting of an outer ring 13, an inner ring 16 and first and second flanges, referenced 191 and 192, respectively. The flanges (see FIGS. 3 and 5) each extend in an axial plane, and sandwich the outer and inner rings 13 and 13. A ring of weights 35, of axis X, and a ring of synchronizers 38, X axis, are disposed between an inner bearing surface 28 of the inner ring 16, and an outer bearing surface 31 of the outer ring 13. The inner bearing surfaces 28 and outer 31 extend parallel to the axis X. The flywheels 35 and synchronizers 38 are constituted by a plurality of weights 39 and synchronizers 40, respectively, which are freely movable between the inner bearing surfaces 28 and outer 31. Support The outer rings 13 and inside 16 of the support 10 are concentric and coaxial with the axis X. Preferably, they each have a substantially constant thickness, preferably less than 20 mm, or even less than 10 mm and / or greater than 2 mm, or even greater less than 3 mm. Preferably, the outer 13 and inner 16 rings have the same thickness "Ea".

Preferably, the outer ring 13 and inner ring 16 each define first axial faces 141 and 14'i respectively, preferably coplanar, and second axial faces 142 and 14'2, respectively, preferably coplanar. The inner ring 16 has a central recess 41, of axis X, in which a transmission shaft can be engaged along the axis X. Preferably, the inner bearing surface 28 and / or the bearing surface outer 31 presents (s) a corrugated profile, adapted to the vibrations to absorb. The corrugations are preferably regular, that is to say have a constant waving period. Preferably, the number of corrugations of the inner bearing surface 28 is equal to the number of corrugations of the outer bearing surface 31. Preferably, the number of corrugations corresponds to the number of weights, corresponding itself to the number of synchronizers. Preferably, the peaks of the corrugations of the inner bearing surface 28 coincide radially with the peaks of the corrugations of the outer bearing surface 31.

In other words, a concavity, respectively a convexity, of the inner bearing surface 28 is superimposed radially with a concavity, respectively a convexity of the outer bearing surface 31. The elements constituting the support 10, in particular the outer ring 13 and the inner ring 16 can be obtained by molding or machined in a block. The profile, particularly corrugated, of the inner bearing surface 28 and / or outer 31 may result from molding, or may be obtained by cutting, milling, or any other suitable machining means. As illustrated in FIGS. 1 to 3, the outer and inner bearing surfaces 31 define paths on which the peripheral surfaces of the flyweights and synchronizers, respectively, can bear during at least part of their displacements. They limit the radial movements of the flyweights outwards and synchronizers inward and thus define their outer and inner radial abutment positions, respectively. In longitudinal section of the support in a plane containing the X axis, the bearing surfaces may for example have a flat profile (for example for the support of a cylindrical roller), or crenellated, or W-shaped , from "U" (see Figure 12), from "V".

As illustrated in FIG. 1, the flanges 191 and 192 may each have the shape of an annular disk of axis X having a central recess and may each be fixed on the first and second axial faces of the outer rings 13 and inner 16, by For example, by means of rivets 22. The central recesses of the flanges can each be superposed on the recess 41 of the inner ring 16. The flanges are preferably shaped to limit the axial displacements of the weights and synchronizers. They thus overlap, at least partially, preferably completely, with the weights 39 and the synchronizers 40. Preferably, the axial displacement of a flyweight 39 and / or a synchronizer 40 is greater than 0.1 mm, or even greater at 0.5 mm, and / or less than 3 mm, or even less than 1 mm. Preferably, the two axial faces of flanges are substantially parallel, at least in the part where they are superimposed on the inner and outer rings. Preferably, the flanges may further comprise, as illustrated in the embodiment of Figure 5, buttonholes 80. They can also, as illustrated in Figure 14 have a boss 20, which is obtained for example by stamping. Preferably, the thickness "Ef" of a flange is less than the thickness "Ea" of the outer ring 13 and / or inner 16 in the portion where said flange is superimposed on said rings. Preferably, the thickness "Ef" is less than 0.5 * "Ea", or even less than 0.2 * "Ea", or even less than 0.1 * "Ea".

Preferably, the thickness of a flange is less than 8 mm, preferably less than 5 mm, preferably less than 3 mm. The overall thickness "Es" of the support, measured along the X axis of rotation of the device, preferably at least in the regions in which the outer 13 and inner 16 rings are sandwiched between the flanges 191 and 192, is preferably less than 25 mm, or even less than 20 mm and / or greater than 5 mm, or even greater than 10 mm. The support 10 can define a cage for the flyweights and / or the synchronizers 38, that is to say have a shape ensuring that the flyweights and synchronizers remain contained in the support during their movements. The cage can be closed, in particular to prevent the intrusion of harmful elements, for example dust, which can in particular be housed in the contact zone between a feeder and a synchronizer and alter the quality of vibration absorption. Alternatively, this cage may be partially open. The support 10, especially the outer rings 13 and inner 16 and the flanges, and / or the weights 39 and / or the synchronizers 40 may in particular be made of metal alloy, preferably an aluminum alloy or steel, in particular steel treated, for example 16MnCr5 carbonitrided. The support may comprise bores for fixing, for example by means of rivets, the support to other parts of the vibration absorption device, for example to a support web of a double damping flywheel. These bores may in particular be arranged at equal distance from the axis X. Weights and synchronizers As shown in Figure 1, each synchronizer 40 of the synchronizer ring 38 is interposed between two adjacent weights. The synchronizer prevents any contact between said weights, in particular in the outer radial abutment positions shown, resulting from a positioning of the synchronizers and flyweights under the effect of the centrifugal force. The weights 39 and the synchronizers 40 are preferably arranged all around the axis X, thus constituting the rings of flyweights 35 and synchronizers 38, of axis X. Preferably, the weights 39 and the synchronizers 40 are distributed substantially equiangularly. around the X axis. As illustrated in FIG. 1, the synchronizers 40 are preferably arranged radially inside the flyweights 39 of the flywheel crown 35. The flyweights and the synchronizers have shaped peripheral contact surfaces to ensure that the contacts between any flyweight and an associated synchronizer are exclusively linear and / or punctual. Preferably, the flyweights and the bearing surface of the support limiting their radial displacement (that is to say determining their outer radial abutment positions, namely, in FIG. 1, the external bearing surface 31), have contact surfaces shaped to ensure that the contacts between any flyweight and said bearing surface are exclusively linear and / or point, which limits friction and noise, allows a high manufacturing tolerance and facilitates assembly. Linear contact is particularly possible when, in a sectional plane passing through the instantaneous axis of rotation and a point of contact, as shown in FIGS. 10 to 13, the profiles of the contact surfaces of the weight and the synchronizer, or fractions of these profiles, are complementary. The contact can be continuous or discontinuous. All linear fractions of a discontinuous contact may be aligned, in particular parallel to the X axis, or non-aligned, for example for a crenellated contact surface profile, depending on whether contact is made only on the vertices or the bases of the crenellations, or is carried out at the same time on the summits and the bases of the crenellations, respectively. A line of contact may be rectilinear or not. It can in particular be broken, for example in the form of "W" or "V". The contact can be punctual, especially when the profiles of the peripheral surfaces of the flyweight and the synchronizer (or a fraction of these profiles) are not complementary. For example, a first of the profiles of the flyweight and the synchronizer may be convex and cooperate with a second profile of the synchronizer and the convex, flat, or even concave flyweight, provided that the curvature of this concavity is locally lower than the curvature of the the convexity of said first profile. A point contact advantageously limits the friction. In one embodiment, the contact may be punctual and partly linear. A form of ball for the synchronizer and / or the flyweight makes it easy to establish a point contact. A flyweight and / or a synchronizer preferably has a shape of revolution around a Y or Z axis, respectively, substantially parallel to the axis X, preferably in the form of a cylindrical roller, a barrel, a a ball, or a diabolo. Preferably, a flyweight and / or a synchronizer has a cylindrical shape. In longitudinal median section (section passing through the axis of revolution), a flyweight or a synchronizer may in particular have, along its contact surface, a flat profile (for example for a cylindrical roller), or crenellated, or shaped "W" (see the flyweight of Figure 11), "U" (see the synchronizer of Figures 11 and 12), or "V" (see Figure 10). The lateral faces of a feeder or a synchronizer, preferably axial, may in particular be planar. They can be curved, as for example illustrated in FIG. 2, FIG. 12 and FIG. 14. Thus, in the case where the flyweight or the synchronizer is in axial abutment, for example against an axial face of the flange, the friction is limit.

As illustrated in FIG. 14, bosses 20 of the first and second flanges may in particular cooperate with the lateral faces, for example curved, or with pins of a flyweight and / or a synchronizer. Thus the guides of the flyweights and the synchronizer are improved, their radial movements being limited. This results in improved vibration filtration, especially for low engine speeds of less than 200 revolutions per minute. The bosses 20 may form a circular chute extending preferably all around the X axis, thus allowing a 360 ° guidance, unlike a buttonhole. In addition, the bosses 20 can be obtained by simply stamping the flanges. As illustrated in FIG. 13, a flyweight may also have a groove and / or a radially extending annular bead adapted to cooperate with an annular bead and / or respectively a groove formed in an adjacent synchronizer and / or in the surface. 31. The flyweights and synchronizers may have shapes that are not revolutionary. In this case in particular, as represented in FIGS. 8 and 9, their shapes can be adapted as a function of the positioning of the desired masses in the inner and outer radial abutment positions, and in particular the positioning of the centers of inertia in these positions. . For example, the embodiment of FIG. 9 makes it possible to increase the mass of the flyweights at the periphery, and thus to effectively damp the vibrations with a minimum space requirement.

Said contact surfaces are preferably determined to ensure, during displacement between two radial outer abutment positions, bearings of the flyweights on the synchronizers and / or on the support surface of the support limiting their radial displacement. Sliding movements are possible, however. Preferably, the synchronizers and the bearing surface of the support limiting their radial displacement towards the X axis (that is to say determining their internal radial abutment positions, namely, in FIG. internal support 28), have contact surfaces shaped to ensure that the contacts between any synchronizer and said bearing surface are exclusively linear and / or point. Said contact surfaces are preferably determined to ensure, during displacement between two radial inner abutment positions, synchronizer bearings on said bearing surface limiting their radial displacement. Sliding movements are possible, however. The profiles of contact surfaces can also be determined to limit the axial movements of the flyweights and / or synchronizers. Preferably, a synchronizer 40 has a shape identical to that of a feeder 39. Their respective dimensions may, however, be different, as shown in Figure 3. The synchronizers 40 advantageously participate, like the weights 39, filtration. It is therefore preferable that the synchronizers have a diameter greater than 0.5 times that of the flyweights, preferably greater than 0.6 times, greater than 0.7 times, greater than 0.8 times, greater than 0.9 times, same or greater than the diameter of the weights. The largest dimension of a flyweight, measured perpendicularly to the X axis, is preferably less than 60 mm and / or greater than 10 mm. The largest dimension of a synchronizer, measured perpendicular to the X axis, is preferably less than 50 mm and / or greater than 5 mm. Preferably, when a flyweight and / or a synchronizer is a ball and / or a roller, the ratio of the diameter of a flyweight to the diameter of a synchronizer is preferably greater than or equal to 1 and / or less than 5. said diameters being measured in an axial center plane of said flyweight and said synchronizer. Particularly preferably, the ratio of the diameter of a flyweight to the diameter of a synchronizer is 1. It may then be possible to use the same type of ball or roll for the synchronizer and the flyweight. The manufacturing costs of the absorption device are thus limited. Preferably, regardless of the angular position about the X axis, the radial distance 30 between the outer bearing surface 31 and the inner bearing surface 28 is less than the sum of the diameter of a synchronizer and the diameter of any of the two adjacent flyweights associated with the synchronizer so that, during the oscillation movement, the synchronizer necessarily remains interposed between said flyweights. The synchronizers are, however, shaped to prevent contact between the two weights which are each adjacent to them. In the embodiment shown in FIG. 1, the flyweights and / or the synchronizers are housed between the flanges 191 and 192. In a variant, as illustrated in FIG. 5, the flyweights and / or the synchronizers can enter one or both of them. flanges 191 and 192, or the (s) cross. Preferably, the thickness of the weights "E" and / or synchronizers "Ee" is less than 2.0 * Ea, preferably less than 1.5 * Ea, preferably 1.1 * E ', or even less than 1.0 * Ea, or less than 0.95 * E, (see Figure 2). Preferably, the thickness Ee and / or En is greater than 5 mm, preferably greater than 8 mm and / or less than 20 mm, preferably less than 15 mm. In particular, the thickness of a flyweight and / or a synchronizer can be adapted to the torque developed by the motor, at the output of which the device according to the invention can be arranged. It is thus possible to expand a roller and / or a flyweight for motors developing high torques. Operation Preferably, after mounting the vibration absorbing device on a transmission of a vehicle, the X axis is substantially orthogonal to the direction of Earth's gravity. In the absence of rotation of the support, the weights located in the lower part of the device rest on the outer ring 13 and the synchronizers are based on the weights. Preferably, the device is configured so that, in the upper part of the device, the weights rest on at least one synchronizer, without being in contact with the outer bearing surface 31 while the synchronizers rest on the inner bearing surface 28. When rotating the support around the X axis, the weights 39 and the synchronizers 40 undergo the effect of the centrifugal acceleration. Preferably, the device is configured so that the synchronizers 40 are detached from the inner ring under the effect of this acceleration. The weights 39 are then compressed between the synchronizers 40 and the support 10. Each pair of adjacent flyweights being separated by a synchronizer 40, the flywheel ring 35 is compressed by the ring of synchronizers 38 against the outer bearing surface 31. outer bearing surface 31 thus defines outer radial abutment positions for the flyweights. Under the effect of variations in rotational speed of the motor, the flyweights and synchronizers interposed between said weights oscillate relative to the support, in an axial plane, substantially all the positions occupied during the oscillations being outer radial abutment positions. The flyweights and synchronizers are guided in a radial and orthoradial path by rolling the flyweights along the outer bearing surface 31. The flanges limit the axial movement of the flyweights and synchronizers. A flyweight 39 can oscillate between two successive peaks 32 of the outer bearing surface 31, or, in one embodiment, move beyond one of these peaks 32, or even beyond each of these vertices. During sudden variations in the speed of rotation of the support around the X axis, the flyweights turn on themselves in a direction of rotation opposite that of the support, and each synchronizer rotates in a direction opposite to that of the weights with which he is in contact. During a sharp deceleration of the rotation of the support, two consecutive synchronizers of the ring of synchronizers can come into contact with each other. This contact brakes said two synchronizers. The speed of rotation of the weights 39 with which these synchronizers are in contact is then abruptly reduced. Other Embodiments FIGS. 4 and 5 illustrate a second embodiment of the invention which differs from the first embodiment in that each weight 39 and each synchronizer 40 comprise a pin 92, 95 respectively, preferably two pins which protrude laterally, preferably along the axis of revolution of the weight and the synchronizer. The presence of two pins improves the accuracy of the guidance by these pins, especially during sudden changes in speed of rotation of the absorption device, for example due to an impact or a stop engine.

The feeder pins 92 and / or synchronizer 95 cooperate punctually or permanently with the edges 97 of the buttonholes 80 defined in the support, in particular in the flanges. These buttonholes define orthorodial stops 98 and 99 for the flyweights and synchronizers, preferably in both directions, preferably so that the displacement of a flyweight is limited between two successive peaks 32. In the embodiment illustrated in FIG. 5, a buttonhole cooperating with a flyweight, with a synchronizer, respectively, defines an internal, external radial abutment position, respectively, for the flyweight, for the synchronizer respectively.

As illustrated in FIG. 15, the buttonhole with which a synchronizer cooperates, a flyweight respectively, can be arranged so that no contact can be established between the synchronizer pin, the feeder pin respectively, and the edge directed towards the inside, the outwardly facing edge respectively, of said buttonhole. In another embodiment not shown, the buttonhole of a flyweight can define at least one, or all, of the outer radial abutment positions for the weight, by pressing at least one pin of the weight on an edge 97 of said buttonhole. The buttonhole of a synchronizer may also define all or part of the internal radial abutment positions by pressing at least one pin of the synchronizer. The vibration absorbing device shown in FIGS. 6 and 7 is a variant which comprises flyweight separators 120 arranged in a ring around the X axis, and synchronizer separators 123, also arranged in a ring, all around. The separators of weights and synchronizers are each arranged between two weights 39 and between two successive synchronizers 40, respectively, so as to limit the orthoradial displacement of said weights and said synchronizers, respectively, and to prevent any contact between said successive weights and said successive separators, respectively. Preferably, the separators are sandwiched between cheeks 1261 and 1262 and are attached thereto. They preferably extend substantially radially. Preferably, the cheeks are in the form of disks, preferably X-axis coaxial, preferably each having a recess in which the inner ring 16 is inscribed. The separators of weights and synchronizers are preferably shaped to limit the radial outward and inward movements of the flyweights and synchronizers, respectively. In cooperation with the cheeks, they can thus constitute a cage adapted to retain the weights and synchronizers housed therein, forming with said cheeks, said weights and said synchronizers an autonomous assembly, or "barrel", easy to handle and mount, for example between two inner and outer rings of a support as described above.

The barrel can be fixed by any means on the support. Of course, the invention is not limited to the embodiments described and shown. In particular, synchronizer and / or feeder buttonholes can limit the movement towards the X axis or outwardly of synchronizers and / or flyweights. The presence of the inner ring 16 and / or the outer ring 13 is then optional.

In addition, the cheeks could be formed by the flanges. The separators could also be formed by extensions of the rings 13 and 16, as shown in FIGS. 8 and 9. In general, all the synchronizers are preferably identical and cooperate in a similar way with the support and the weights.

In general, all the weights are preferably identical and cooperate in a similar manner with the synchronizers and the weights. All possible combinations of the characteristics relating to the different characteristics, and in particular to the different main aspects of the invention are envisaged.

Claims (15)

REVENDICATIONS1. Vibration absorbing device for a motor vehicle transmission, said device having an axis X of rotation and comprising a support (10), two adjacent weights (39) and a synchronizer (40) associated with said weights, the flyweights and the synchronizer being freely movable on the support, and being able to be arranged according to a set of positions, called "external radial stop positions", in which the flyweights and the synchronizer can no longer be displaced outwards in a radial direction, the synchronizer being interposed between the weights so as to prevent any contact between said weights, and so as to be in linear contact and / or punctual with said weights regardless of the outer radial abutment position considered. 2. Device according to the preceding claim comprising a crown of X-axis flyweights (35) and an X axis synchronizer ring (38), the flyweights and synchronizers being freely movable on the support and being able to be arranged in positions said "outer radial stop positions" in which the flyweights and synchronizers can no longer be displaced outwardly in a radial direction, each pair of two adjacent flyweights being associated with a synchronizer interposed between said two adjacent flyweights so as to prevent any contact between said two adjacent flyweights and be in linear and / or point contact with said two adjacent flyweights regardless of the outer radial stop position considered. 3. Device according to any one of the preceding claims, the synchronizer (s) being radially inner (s) relative to the adjacent adjacent weights. 4. Device according to any one of the preceding claims, the synchronizer (s) and / or at least one of the weights having the shape of a ball or a cylinder-shaped or barrel-shaped roll, one or more of lateral faces of the roll being optionally curved. 5. Device according to the preceding claim, the ratio of the diameter of two of said adjacent flyweights on the diameter of the associated synchronizer being greater than 1 and less than 5, the diameters being measured in a median plane orthogonal to the X axis. 6. Device according to any one of the preceding claims, comprising a bearing surface guiding the displacement of said weights between said outer radial abutment positions, and / or having a bearing surface guiding the movement of the synchronizer (s). between a set of inner radial abutment positions in which the synchronizer (s) can no longer be moved inward in a radial direction, at least one of said bearing surfaces being defined by a surface (31; 28) a ring (13; 16) of the support or an edge (97) of a buttonhole (80) of the support. 7. Device according to the preceding claim, said bearing surface having a corrugated profile. 8. Device according to any one of the preceding claims, comprising a separator (120; 123) secured to the support and interposed between the two adjacent weights, and / or two adjacent synchronizers, so as to limit the orthoradial and / or radial displacements of said weights and / or said synchronizers. 9. Transmission of a motor vehicle selected from a friction clutch and a hydrokinetic converter, said transmission comprising a vibration absorbing device according to any one of the preceding claims. 10. Motor vehicle equipped with a transmission according to the preceding claim. 11. A vibration absorption device for a motor vehicle transmission, said device having an axis X of rotation and comprising a support (10), two adjacent flyweights (39) and a synchronizer (40) associated with said flyweights, the weights and the synchronizer being freely movable on the support, and being able to be arranged according to a set of positions, called "external butéeradiale positions", in which the flyweights and the synchronizer can no longer be displaced outwards in a radial direction, the synchronizer being interposed between the weights so as to prevent any contact between said weights, the synchronizer and / or the weights respectively having a cylindrical shape, the lateral faces of the synchronizer and / or the weights being curved. 12. Vibration absorbing device for a motor vehicle transmission, said device having an axis X of rotation and comprising a support (10), two adjacent flyweights (39) and a synchronizer (40) associated with said flyweights, the the flyweights and the synchronizer being freely movable on the support, and being able to be arranged according to a set of positions, called "external radial stop positions", in which the flyweights and the synchronizer can no longer be displaced outwards in a radial direction , the synchronizer being interposed between the weights so as to prevent any contact between said weights, the synchronizer and / or the weights having non-revolution shapes. 13. Vibration absorbing device for a motor vehicle transmission, said device having an axis X of rotation and comprising a support (10), two adjacent weights (39), a synchronizer (40) associated with said weights and a separator (120; 123), the flyweights and the synchronizer being freely movable on the support, and being able to be arranged according to a set of positions, called "external radial stop positions", in which the flyweights and the synchronizer can no longer be moved outwardly in a radial direction, the synchronizer being interposed between the weights so as to prevent any contact between said weights, the separator being integral with the support and interposed between the two adjacent weights, and / or two adjacent synchronizers respectively, and being shaped to limit radial outward and inward movements of the flyweights and / o u synchronizers respectively. 14. Device according to the preceding claim, comprising cheeks (1261; 1262) extending radially and taking the sandwich separator, said separator cooperating with said cheeks to form a cage adapted to retain the weights and / or synchronizers therein housed. 15. A vibration absorption device for a motor vehicle transmission, said device having an axis X of rotation and comprising a support (10), two adjacent flyweights (39), a synchronizer (40) associated with said flyweights, the the flyweights and the synchronizer being freely movable on the support, and being able to be arranged according to a set of positions, called "external radial stop positions", in which the flyweights and the synchronizer can no longer be displaced outwards in a radial direction , the synchronizer being interposed between the weights so as to prevent any contact between said weights, the device comprising a bearing surface defined by a buttonhole and guiding the displacement of said weights between said outer radial abutment positions and / or a surface of support defined by a buttonhole and guiding the movement of the synchronizer between a set internal radial abutment positions in which the synchronizer can no longer be moved inwardly in a radial direction.