FR3058195B1 - FILTERING MECHANISM BETWEEN TWO ROTATING BODIES AND CLUTCHES EQUIPPED WITH SUCH A MECHANISM - Google Patents

Abstract

The invention relates, on the one hand; a filtering mechanism (X) for motor torque fluctuations around an axis of revolution (100) for a motor vehicle clutch (Y) comprising at least two members, respectively, a primary member (1) and a secondary member ( 2), rotating about the axis of revolution being able to oscillate angularly with respect to each other, an elastic potential energy accumulator (R1, R2) mounted between said members and means for locking said bodies temporarily blocking their relative angular oscillation, characterized in that said locking means comprise an actuator (A) capable of exerting axial forces (F1, F2) transmitted to at least one intermediate member (3) integral in rotation with the one of the primary (1) or secondary (2) bodies and carrying a stop element (33) engaging, under the action of said forces, with the other member to ensure their mutual blocking and, secondly; clutches equipped with said filtering mechanism; and a method of locking a filtering mechanism.

Description

FILTERING MECHANISM BETWEEN TWO ROTATING BODIES AND CLUTCHES EQUIPPED WITH SUCH A MECHANISM

The invention relates to an improved filtering mechanism, to clutches equipped with such a mechanism and to a locking method of a filtering mechanism.

More specifically, the invention relates to a filter mechanism equipped with locking means of the double damping flywheel.

STATE OF THE PRIOR ART

To mitigate the torque fluctuations between a heat engine and a gearbox, it is known to equip the clutches with a filter mechanism with a double damping flywheel. This double-steering wheel generally comprises a primary flywheel of torque entry, rotating about an axis of revolution, and a secondary flywheel of torque output, able to oscillate angularly with respect to the primary member in directions, respectively, direct and retrograde oscillation, between two end positions and between which is interposed at least one potential elastic compression energy accumulator.

However, these filtering mechanisms have a resonant frequency, in particular in the starting and revving phases of the engine or below the idle speed before stopping the vehicle. However, these phases cause significant shocks, when the range of resonant frequencies is crossed.

In these conditions, it has been important to block the damper of the filter mechanism when the engine speed passes through these phases to avoid relative angular displacement between the primary flywheel and the secondary flywheel.

A locking solution of the double-steering wheel is described, in particular, in FR 2,822,210. In this solution, the locking of the secondary flywheel is ensured by the movement of the assembly consisting of the secondary flywheel and the clutch. . The mass of these components being high, their displacement requires a complex guidance system and a return system capable of producing a significant effort.

In addition, the engagement of the locking system requires a high thrust force capable of compensating the return force and quickly move the mass of the secondary flywheel and the clutch. This type of system therefore requires resorting to complex, heavy and expensive means.

However, the technical solutions envisaged so far required the use of complex external means to temporarily secure the primary and secondary flywheels between them.

STATEMENT OF THE INVENTION

The invention aims to overcome the drawbacks of the state of the art by seeking to eliminate or at least significantly reduce the resonance phenomena to avoid shocks and resulting noise and without resulting in disturbances in the behavior of the filtering mechanism outside the critical phases.

For this purpose, the invention proposes an improvement of the filtering mechanisms of motor torque fluctuations around an axis of revolution for a motor vehicle clutch, comprising at least two members, respectively, a primary member and a secondary member. , rotating around the axis of revolution being able to oscillate angularly with respect to each other, locking means of said members ensuring the temporary blocking of their relative angular oscillation and an elastic potential energy accumulator mounted between said members, characterized in that said locking means comprise an actuator adapted to exert axial forces of traction or thrust transmitted to at least one intermediate member integral in rotation with one of the primary or secondary members and carrying a stop element engaging, under the action of said forces, with the other organ to ensure their mutual blocking el.

According to an advantageous characteristic, the locking means are arranged to move the abutment member of an unlocked position in which the primary and secondary members can rotate relative to each other with respect to the axis of rotation, to a locked position in which the primary and secondary members are integral in rotation.

According to an advantageous characteristic of the invention, the actuator is provided with a transverse bearing face coming, under the action of the forces, in contact with the intermediate member and an actuating face of the clutch.

Preferably, this transverse bearing face is carried by a cup coming into contact with a peripheral flange carried by the intermediate member.

According to an advantageous characteristic, the stop element and the flange have respective ends provided with flexible tongues snapped into corresponding orifices formed, respectively, in the secondary member and in a washer carrying the friction discs of the clutch.

According to another characteristic, the mechanism comprises at least one elastic return element opposing the axial forces exerted by the actuator and acting on the intermediate member.

According to a preferred variant, the actuator consists of a clutch control.

According to yet another characteristic, the stop element is connected to the intermediate member via a shoulder extending substantially axially.

According to another advantageous characteristic, the mechanism comprises, in addition, two elastically deformable washers, one of which is disposed between the secondary member and the abutment element and the other between said abutment element and the shoulder and intended to facilitate, by the return of their potential energy, respectively, the unlocking and locking of the two bodies.

According to a first specific variant, the intermediate member is mounted on the secondary member and the abutment member is formed in the form of a striker intended to engage axially in an orifice formed opposite in the primary member to move from an unlocked position to a locked position.

According to an advantageous characteristic, a guide ramp formed in the primary member or in the secondary member is arranged to cooperate with a counter-ramp of said striker so as to axially remove the striker from the orifice to pass through. a locked position to an unlocked position.

In this case, the intermediate member is connected, on the one hand, to said striker and, on the other hand, to the actuator via spacers washers receiving pivoting intermediate elements.

According to other specific variants, the intermediate member is mounted on the primary member and the stop member consists of an inner face of the shoulder of the intermediate member which comes into frictional contact with a side of the secondary organ.

In this particular case, the inner face of the shoulder forming the abutment member has a conical profile complementary to the end edge of the secondary member.

According to another specific variant, the shoulder of the intermediate member is extended externally by a cover whose radially inner edge is in contact with the actuator.

In a preferred configuration, the inner edge of said lid is subjected to axial thrust forces exerted by the actuator.

In these latter variants, it is possible to provide that the stop element is carried by the elastic return element.

According to the most general embodiment of the invention, the primary member is the engine torque input member while the secondary member corresponds to the torque output to the input shaft of the invention. the gearbox.

Another object of the invention is a clutch for motor vehicles characterized in that it is normally open and equipped with a lockable filtering mechanism having the characteristics defined above.

Still another object of the invention is a clutch for motor vehicles characterized in that it is normally closed and equipped with a lockable filter mechanism having the characteristics defined above.

The invention also relates to a locking method of a filtering mechanism as referred to above.

The invention finds more particularly its application in the filtering mechanisms to at least two rotating members and, preferably, to those comprising a primary member and a secondary member as described in FR 2,822,210.

With the improvement of the invention, it becomes possible to avoid the harmful phenomena related to the crossing of the resonance range of the damper double-flywheel, in particular during the phases of declutching or slowing the engine.

BRIEF DESCRIPTION OF THE FIGURES Other features and advantages of the invention will emerge on reading the description which follows, with reference to the appended figures and detailed below. FIGS. 1A, 1B and 1C show sectional views of a clutch equipped with a first embodiment of the mechanism of the invention in position, respectively; engaged, disengaged and disengaged-locked, Figures 2A, 2B and 2C show sectional views of a clutch equipped with a second embodiment of the mechanism of the invention in position, respectively; engaged, disengaged and disengaged-locked, Figs. 3A, 3B and 3C show sectional views of a clutch equipped with a third embodiment of the mechanism of the invention in position, respectively; engaged, disengaged and disengaged-locked, Figures 4A, 4B and 4C show sectional views of a clutch equipped with a fourth embodiment of the mechanism of the invention in position, respectively; engaged, disengaged and disengaged-locked,

FIG. 5 shows a sectional view of an alternative embodiment of the mechanism of the invention of FIGS. 1A-1C in the engaged position, FIGS. 6A, 6B, 6C (in partial view) and FIG. 6D, sectional views. a clutch equipped with another variant of the embodiment of the mechanism of the invention of Figures IA to IC in position, respectively; engaged, disengaged, disengaged, disengaged and disengaged,

FIG. 7 represents a partial exploded perspective view of the variant of FIGS. 6A to 6D,

Figure 8 shows a partial exploded perspective view of another variant of the invention.

For the sake of clarity, identical or similar elements are marked with identical reference signs throughout the figures.

DETAILED DESCRIPTION OF EMBODIMENTS

Of course, the embodiments illustrated by the figures presented above are given by way of non-limiting examples. It is explicitly provided that these different modes and variants can be combined with one another to propose others.

The invention relates to a filter mechanism integrated in a transmission chain between a crankshaft (for example of internal combustion engine, not shown) and an input shaft of a gearbox (not shown). This mechanism filters the speed and torque fluctuations between the crankshaft and the clutch and comprises, as shown in the figures, a primary rotating member 1, a secondary rotating member 2 and at least one bidirectional elastic potential energy accumulator .

In the embodiments shown in the figures, the primary member 1 constitutes the inlet of the filter mechanism, that is to say that it is arranged to receive the torque transmitted by the engine and the secondary member 2 is the output of the filter mechanism, that is to say, it is arranged to transmit to the gearbox, the torque from the filter mechanism.

Alternatively and without departing from the scope of the invention, the secondary member may however be the input of the filter mechanism while the primary member may be the output of the filter mechanism.

As illustrated here by the sectional views of assemblies consisting of clutches (reference Y on the right side of the figures) and associated filtering mechanisms (reference X on the left side of the figures), the primary member 1 d The torque inlet essentially comprises two guide washers 11, 12 fixed to each other and to the crankshaft of the engine (not shown). A web 15 mounted on a central centering ring 13 is integral with the secondary member 2 which forms the output of the filter mechanism X and provides the connection with the clutch Y. In general, the clutch Y comprises at least one friction disc G (and in FIG IA, two discs) engaging the secondary member 2 in the engaged position and driving a hub 14 in rotation about the axis of revolution 100 and engaged with the shaft of gearbox input (not shown). The invention is equally applicable to a double clutch comprising two hubs.

The guide washers 11, 12 are provided with curved recesses for an elastic potential energy accumulator formed of helical springs R1, R2 in series. Each spring is supported by one end against a rim of the housing of the guide rings of the primary member 1.

It follows from this arrangement that the web 15 of the secondary member 2 rotates angularly oscillating relative to the guide washers 11, 12 of the primary 1 about the axis of revolution 100 between two end positions.

A so-called phasing washer 16 provides the connection between the two springs R1, R2 in series. The forces exerted by the springs RI and R2 on this washer oppose and balance.

The filtering mechanism further comprises means for locking the two members 1, 2 and ensuring the temporary blocking of their relative angular oscillation.

According to the invention, these locking means comprise, in particular, an actuator A capable of exerting axial thrust forces transmitted to at least one intermediate member 3 mounted coaxially with the axis of revolution 100 and rotatably integral with it. of one of the primary member 1 or secondary 2 by means of at least one elastic return element 4 opposing the axial forces exerted by the actuator A. This actuator is arranged to move axially the intermediate member 3.

This intermediate member 3 carries a stop member 33 adapted and intended to come into engagement, under the action of these forces, with the other member to ensure the locking in relative rotation of the primary and secondary members and their mutual locking .

In all the embodiments shown in the accompanying figures, the kinematic transmission of forces between the actuator A and the stop element 33 is shown by a path in solid lines.

The actuator A is mounted on the axis 100 near the hub 14. This actuator is here a hydraulic cylinder provided with a peripheral piston P surrounding the box input shaft.

However, it would be possible, according to other variants of the invention not shown in the present figures, to use other types of actuators chosen for an association with the locking filter mechanism of the invention and for example, actuators with electric motor.

The actuator A used in the various variants shown of the invention will be the control cylinder of the clutch (called "Concentric Slave Cylinder") whose main function is to ensure the displacement of the diaphragm D. This actuator being necessary for the clutch to ensure the function mentioned above, the allocation of this second function makes it possible not to clutter the filtering mechanism and to preserve the original compactness.

The actuator A is provided with a transverse bearing face Al coming, in the disengaged position (FIGS. 1B and 1C), under the action of the forces generated by the piston P, in bearing contact with the intermediate member 3 by compressing the return elements 4. On the other hand, in the engaged position, (FIG. 1A), the piston P is retracted and the face Al is then at a distance from the intermediate member 3.

For this purpose, the transverse support face Al is carried by a cup A2 which comes into contact with a peripheral flange 31 of the intermediate element 3, via pivoting, sliding or sliding intermediate elements B, such as ball bearings or thrust bearings. The cup A2 has a contact face with the flange 31 and a contact face for actuating the clutch Y.

The stop member 33 is, in turn, connected to the intermediate member 3 by a shoulder 32 extending substantially axially.

The abutment element 33 and the shoulder 32 to which it is connected, are not necessarily made around the entire periphery of the intermediate element 3. Indeed, to ensure a reliable and stable locking of the primary members 1 and secondary 2, it is sufficient that the shoulder 32 is made locally on at least two appropriate angular regions of the circumference of the intermediate element 3 and, preferably, on two diametrically opposite zones or more than two zones distributed uniformly on the periphery. of the intermediate element 3.

The intermediate member 3 is mounted on one of the primary member 1 or secondary 2 by means of at least one elastic return member 4 opposing the axial forces exerted by the actuator A.

The invention will now be described with reference to the embodiment of Figures IA to IC which corresponds to a clutch said "normally closed". The intermediate member 3 is mounted on the secondary member 2 and the stop element 33 is designed as a striker 331 for locking the primary member 1 with the secondary member 2.

The intermediate member 3 is connected, on the one hand, to the striker 331 and, on the other hand, to the actuator A via spacer washers E receiving pivoting or sliding intermediate elements B providing an interface dynamic with low coefficient of friction.

Indeed, the abutment element 33 is integral in rotation with the secondary member 2 because the striker 331 is engaged in a slot 20 formed in the plane of the secondary member 2. In contrast, the shoulder 32 is integral in rotation with the friction disc G of the clutch Y. In FIG IA, the flange 31 is also integral in rotation friction discs G.

FIG. 1A corresponds to the engaged position of the filtering mechanism in which the primary 1 and secondary 2 members are free to oscillate relative to each other in a limited angular range so as to damp, in cooperation with the springs RI, R2, the vibrations of the motor. In this position, the transverse bearing face Al of the cup A2 of the actuator A is not in contact with the flange 31 of the intermediate element 3.

The intermediate member 3 cooperates, moreover, with resilient return elements 4 made here in the form of a washer 41 connected to the hub 14 and providing the support of the discs G. The washer 41 is provided with flexible tabs 41a . The intermediate member 3 passes through the washer 41 and therefore the clutch Y in the axial direction between the actuator A and the secondary member 2 and here around the hub 14. According to a variant, not shown, in which the hub would have a large diameter, it would be possible to provide that the intermediate member 3 through the hub.

Figure IB corresponds to the disengaged position of the mechanism. In this state, under the action of the thrust forces El exerted by the piston P, the transverse face Al of the cup A2 of the actuator A comes into bearing contact against the flange 31 of the intermediate element 3 by deforming progressively the flexible tabs 41a of the washer 41. When the actuator A is constituted by the clutch control cylinder, the latter then jointly ensures the movement of the diaphragm to separate the friction discs G flywheel. In this state of the mechanism, the primary organs 1 and secondary 2 still retain their freedom of movement oscillating relative to each other.

Figure IC always corresponds to the disengaged position but after the intervention of the locking means of the invention. In this position, the striker 331 has been displaced, under the action of the thrust force F1 of the actuator A, parallel to the axis 100, in the direction of the primary member 1 to be introduced into the orifice 10 made through the member 1 and located opposite the orifice 2 when no torque is transmitted to the damper. In this state, the two members 1, 2 are locked in relative rotation and therefore without freedom of movement oscillating relative to each other which avoids the risk of resonance.

At the next clutch phase, at the moment of withdrawal of the piston P of the actuator A and thanks to the relaxation of the tabs 41a of the spring washer 41, the intermediate member 3 and the striker 331 will automatically return to the position of Figure IA.

Figures 5 and 6A to 6D correspond to variants of the embodiment of Figures IA to IC in which the intermediate member 3 frees the spacers washers E of the pivoting or sliding elements (bearings B). The intermediate member 3 rests directly on the shoulder 32 carrying the abutment element 33, which is again produced here in the form of a striker 331. The respective rotational speeds of the abutment element 33 and of the shoulder 32 are different which leads to a relative rotary contact which will be optimized to limit the friction between these parts.

The elastic return elements 4 are offset between the shoulder 32 and the secondary member 2 and are here formed as at least one elastic washer 44 and, preferably, two spring washers 44a, 44b, which replaces the flanges 41a of the washer 41. The flange 31 on which are exerted the thrust forces Fl of the piston P of the actuator A, consists of the radially inner edge of the intermediate member 3. A rigid complementary ring 45 receives the support of the end edge of the flange 31.

In the variant of Figures 6A to 6D and 7, the striker 331 and the peripheral edge of the intermediate member 3 are each provided with flexible tongues 330 which project radially outwards and which are snapped, when the assembly, respectively, in the orifice 20 of the secondary member 2 and in an orifice 410 formed in the washer 41 carrying the friction discs G. The tongues 330 are retained axially in the holes in the manner of a harpoon , their free end abutting against the walls of the orifices 20, 410. This mode of elastic restraint is intended to counteract the return action of the washers 44a, 44b.

Figures 6A to 6D illustrate an energy storage lock, the intermediate phase of Figure 6C corresponding to a loading prior to the relaxation of the energy washers 44a, 44b. These spring washers, commonly known as "Belleville" washers, have a frustoconical profile in the free state and are elastically deformed under stress, in particular during assembly of the intermediate member 3 on the clutch and the secondary member 2 by snapping in force. Tongues 330. The support on the flange 31 deforms the washers 44a, 44b and the latter, by shape memory, will restore their potential energy to move the striker, when the striker 331 will be opposite the orifice 10 of the primary organ 1.

The washer 44a disposed between the secondary member 2 and the stop member 33 has the function of facilitating the release to the clutch by pushing on the striker to extract it from the orifice 10 of the primary member 1.

The washer 44b disposed between the abutment element 33 and the washer 45 receiving the support of the flange 31 has the function of facilitating locking after disengagement, releasing the striker 331 when the latter comes opposite the orifice 10 of the primary member 1, as shown in FIG. 6C.

In another embodiment shown in Figure 8, the primary member 1 comprises a ramp 17 arranged to cooperate with a counter ramp of the striker 331. For this purpose, each striker consists of a tooth and the counter-ramp is formed by a cut-off end edge 331a of said tooth. This tooth is intended to be introduced into a cavity 18 defining on the primary member 1 a recessed area inclined edge forming the guide ramp 17 for the cut sections 331a of the tooth.

For reasons, in particular, sealing, the cavity 18 could be made in a non-emergent manner unlike what is shown in Figure 8.

Thus, when the actuator A is in a position allowing unlocking of the locking means and when a torque applied to the primary member 1 reaches a predetermined threshold value, the ramp 17 exerts on the strike 331 a force adapted to move it from a locked position to an unlocked position. It is then possible to dispense with an elastic return means for the return to the unlocked position of the striker.

In another alternative embodiment not shown, the strike comprises a counter-ramp cooperating with a ramp arranged on the secondary member in the locked position and during the passage of the latch from the locked position to the unlocked position.

Nevertheless, the passage of the lock from the locked position to the unlocked position can be assisted by an elastic return means such as a spring washer.

Figures 2A to 2C correspond to a second embodiment of the invention. In this other mode and contrary to the embodiment previously described, the intermediate member 3 is here mounted on the primary member 1 via resilient return elements 4 formed of flexible tongues 42 (visible in Figures 2B and 2C ). This variant corresponds to a so-called "normally open" clutch in which there is no diaphragm and which is used, for example, in automated clutch control boxes.

The stop element 33 consists of an inner face 332 of the shoulder 32 of the intermediate member 3 which cooperates with the end edge 23 of the secondary member 2.

More specifically, the inner face 332 forming the abutment member 33 integral with the primary member 1 has a conical profile complementary to the end edge 23 of the secondary member 2 so that the surfaces facing each other. , respectively, of the face 332 and the edge 23 can establish mutual contact with a sufficient level of friction to prohibit an oscillatory movement between the first member 1 and the second member 2 and ensure their locking, as shown in Figure 2C in position disengaged from the mechanism.

In this embodiment, the shoulder 32 of the intermediate member 3 is extended externally by a cover 34 integral with the shoulder 32 and whose radially inner edge delimits the flange 31 which is here in contact. permanent with the bearing surface Al of the actuator A. The radially inner edge of the cover 34 is disposed outside the cup A2 of the actuator A. In this variant the effort to ensure the locking is provided by a return spring (not shown) which pushes the pressure plate T of the clutch Y relative to the secondary member 2. This return force makes it possible to have a clutch normally open and is greater than the sum rappelling efforts of the tabs 42 and the actuator A.

FIGS. 3A to 3C correspond to a third embodiment of the invention in which the flange 31 of the intermediate element 3 formed of the radially inner edge of the cover 34 is disposed inside the cup A2 of the invention. Actuator A. This other mode still corresponds to a so-called "normally open" clutch.

In this case, in the engaged position of the mechanism (FIG. 3A), the bearing surface A1 on which the thrust forces F2 of the piston P of the actuator A is exerted, holds the flange 31 in its retracted position. where the stop element 33 is kept at a distance from the end edge 23 of the secondary member 2.

The transition to the disengaged position (3B) is effected by displacement of the piston P in the direction F2. The intermediate member 3 with its abutment member 33 is then moved axially by the detent of the tongues 42 resilient return ensuring its connection with the primary member 1 until the inner face 332 of the shoulder 32 comes into contact friction with the edge 23 thus ensuring the locking of the primary and secondary members (Figure 3C).

FIGS. 4A to 4C show a fourth embodiment of the invention always corresponding to a so-called "normally open" clutch and in which the stop element 33 is carried by the elastic return element 4 ensuring the connection of the intermediate member 3 with the secondary member 1. This is the secondary member 2 which consists of the assembly of the guide rings 21, 22.

The elastic return element 4 is formed of a flexible blade 43 whose inner end is riveted to the primary member 1 and its outer end is connected to the shoulder 32 of the intermediate member 3. L outer end of the blade 43 defines, with the shoulder 32, an inner face 334 here constituting the abutment element 33 of the locking means.

When disengaging (Figure 4B), due to the withdrawal in the direction F2 of the piston P of the actuator A and under the effect of the relaxation of the blade 43, the face 334 is closer to the end edge the guide washer 21 to come into contact with its contact to ensure the locking of the primary members 1 and 2 (Figure 4C).

During these last phases, the combined thrust forces of the return element 4 and the clutch Y are much greater than the resistance of the piston P so as to ensure that the blade 43 is abutted and the locking both organs 1, 2.

Claims (20)

A filtering mechanism (X) for motor torque fluctuations around an axis of revolution (100) for a motor vehicle clutch (Y) comprising at least two members, respectively, a primary member (1) and a secondary member ( 2], rotating about the axis of revolution being able to oscillate angularly relative to each other, an elastic potential energy accumulator (RI, R2) mounted between said members and means for locking said bodies temporarily blocking their relative angular oscillation, characterized in that said locking means comprise an actuator (A) capable of exerting axial forces (F1, F2) transmitted to at least one intermediate member (3) integral in rotation with the one of the primary (1) or secondary (2) bodies and carrying a stop element (33) engaging, under the action of said forces, with the other member to ensure their mutual blocking, said actuator (A) being constit ué of a clutch control. 2. Filtering mechanism according to claim 1, characterized in that said actuator (A) is provided with a transverse bearing face (Al) coming, under the action of said forces, in contact with said intermediate member (3). and an actuating face of the clutch (Y). 3. Filtering mechanism according to the preceding claim, characterized in that said transverse bearing face (Al) of the actuator is carried by a cup (A2) coming into contact with a peripheral flange (31) carried by the organ. intermediate (3). 4. Filtering mechanism according to the preceding claim, characterized in that the stop element (33) has ends provided with flexible tongues (330) snapped into orifices (20) formed in the secondary member (2). 5. Filtering mechanism according to one of the preceding claims, characterized in that the flange (31) has ends provided with flexible tongues (330) latched in orifices (410) formed in a washer (41) clutch ( Y) carrying friction discs (G). 6. Filtering mechanism according to one of the preceding claims, characterized in that it comprises at least one elastic return element (4) opposing the axial forces (F1, F2) exerted by the actuator (A) and acting on said intermediate member (3). 7. Filtering mechanism according to one of the preceding claims, characterized in that said stop element (33) is connected to the intermediate member (3) via a shoulder (32) extending substantially axially. 8. Filtering mechanism according to the preceding claim, characterized in that it further comprises two elastically deformable washers (44a, 44b) one of which (44a) is disposed between the secondary member (2) and the stop element (33) and the other (44b), between said abutment element and the shoulder (32) and intended to facilitate, by the restoration of their potential energy, respectively, the unlocking and locking of the two members ( 1, 2). 9. Filtering mechanism according to one of the preceding claims, characterized in that the intermediate member (3) is mounted on the secondary member (2) and the stop member (33) is formed as a strike (331) intended to engage axially in an orifice (10) formed opposite in the primary member (1) to move from an unlocked position to a locked position. 10. Filtering mechanism according to the preceding claim, characterized in that a guide ramp (17) formed in the primary member (1) or in the secondary member (2) is arranged to cooperate with a counter-ramp of said striker (331) so as to axially remove the striker from the orifice (10) to move from a locked position to an unlocked position. 11. Filtering mechanism according to the preceding claim, characterized in that said intermediate member (3) is connected, on the one hand, to said striker (331) and, on the other hand, to the actuator (A) via spacer washers (E) receiving pivotal insert elements (B). Filtering mechanism according to claim 7, characterized in that the intermediate member (3) is mounted on the primary member (1) and the stop member (33) consists of an inner face (332). the shoulder (32) of said intermediate member (3) which comes into frictional contact with a face of the secondary member (2). 13. Filtering mechanism according to the preceding claim, characterized in that said inner face (332) of the shoulder (32) forming the abutment element (33) has a conical profile complementary to the end edge (23) of the secondary organ (2). 14. Filtering mechanism according to claim 12 or 13, characterized in that the shoulder (32) of said intermediate member (3) is extended externally by a cover (34) whose radially inner edge (31) is in contact with the actuator (A). 15. Filtering mechanism according to claim 14, characterized in that the radially inner edge (31) of said cover (34) is subjected to the thrust forces (F1) exerted by the actuator. 16. Filtering mechanism according to claims 5 and 14, characterized in that said stop element (33) is carried by the elastic return element (4). 17. Filtering mechanism according to one of the preceding claims, characterized in that said primary member (1) is the engine torque input member while the secondary member (2) corresponds to the output of the torque to the engine. 'input shaft of the gearbox. Clutch for motor vehicles characterized in that it is normally open and equipped with a lockable filter mechanism according to one of the preceding claims. Clutch for motor vehicles characterized in that it is normally closed and equipped with a lockable filter mechanism according to one of claims 1 to 17. 20. A method of locking a filtering mechanism (X) according to one of claims 1 to 17, characterized in that it makes the locking in relative rotation of the primary organs (1) and secondary (2) by means of an actuator (A) for controlling the clutch (Y).