FR3060683A1 - WEAR RETRACTING MEMBER FOR A CLUTCH MECHANISM, IN PARTICULAR FOR A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a wear compensating member (16) for a clutch mechanism (1), particularly for a motor vehicle, characterized in that it comprises: a first annular element (17) of axis X whose an axial end (19) comprises at least one ramp (20) inclined with respect to the radial plane, intended to cooperate with a counter-ramp (20a) of the clutch mechanism (1), - a second element (22) comprising a annular radially inner portion (23) and a toothed portion (24) connected to the inner annular portion (23), the second member (21) being attached to the first member (17).

Description

060 683

62705 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number:

(to be used only for reproduction orders) (© National registration number

COURBEVOIE © IntCI ⁸ : F16 D 13/75 (2017.01)

PATENT INVENTION APPLICATION

A1

©) Date of filing: 19.12.16. © Applicant (s): VALEO EMBRAYAGES Company by (30) Priority: simplified actions - FR. @ Inventor (s): BRAILLY JULIEN, DELIENCOURT NICOLAS and MARECHAL OLIVIER. (43) Date of public availability of the request: 22.06.18 Bulletin 18/25. ©) List of documents cited in the report preliminary research: Refer to end of present booklet (© References to other national documents ® Holder (s): VALEO EMBRAYAGES Company by related: simplified actions. ©) Extension request (s): ©) Agent (s): VALEO EMBRAYAGES Company by simplified actions.

(04) WEAR SEALING MEMBER FOR A CLUTCH MECHANISM, ESPECIALLY FOR A MOTOR VEHICLE.

FR 3 060 683 - A1 _ The invention relates to a wear take-up member (16) for a clutch mechanism (1), in particular for a motor vehicle, characterized in that it comprises:

- A first annular element (17) of axis X, one axial end (19) of which comprises at least one ramp (20) inclined relative to the radial plane, intended to cooperate with a counter-ramp (20a) of the clutch mechanism (1),

- a second element (22) comprising a radially internal annular part (23) and a toothed part (24) connected to the internal annular part (23), the second element (21) being fixed to the first element (17).

Wear take-up member for a clutch mechanism, in particular for a motor vehicle

The present invention relates to a wear take-up member for a clutch mechanism, in particular for a motor vehicle.

A clutch mechanism belongs, more generally, to a clutch device.

A clutch device conventionally comprises a reaction plate, a clutch mechanism comprising a movable pressure plate, and a friction disc mounted between said reaction and pressure plates. The movement of the pressure plate is controlled by a diaphragm, itself controlled by a clutch stop.

The clutch bearing can be of the actuated actuator, hydraulic control or cable control type, in order to exert a predetermined force on the diaphragm and to move it into a disengaged position.

The pressure plate is thus movable between a clutch position in which the friction disc is clamped between said pressure and reaction plates, and a declutch position in which the friction disc is released.

The use of the clutch device causes wear of the friction disc linings as well as the counter-materials of the associated pressure and reaction plates. This results in a variation of the position of the pressure plate with respect to the associated diaphragm and / or with respect to the reaction plate, generating a variation in the tightening force of the friction disc and a modification of the licking point and the stroke of the clutch bearing. Remember that the licking point is the position from which a torque can be transmitted through the clutch device.

A wear take-up clutch device is known from document FR 2 847 626 in the name of the Applicant. This document discloses a wear take-up clutch device for a motor vehicle, comprising a pressure plate intended to come to bear on a friction disc of the clutch device, a diaphragm serving to actuate the pressure plate between a fully engaged position in which said pressure plate is pushed against the friction disc, and a fully disengaged position in which said pressure plate is moved away from the friction disc by means of return means of the pressure plate.

The pressure plate, the friction disc and the diaphragm are housed in a cover which is fixed relative to the reaction plate.

The device further comprises a member for taking up the wear of the friction disc, interposed between the diaphragm and the pressure plate, and movable in rotation about an axis within a determined range, said take-up member comprising a cooperating ramp with a counter ramp on the side of the pressure plate, so as to adjust the distance between the diaphragm and the pressure plate and compensate for the wear of the friction disc as a function of the position of the ramp relative to the counter ramp .

The clutch device further comprises displacement means comprising a ratchet wheel capable of pivoting around an axis mounted on a cassette. The displacement means also comprise a pawl comprising a body fixed on the cover and an actuating tab cooperating with the ratchet wheel so as to actuate the pivoting of the ratchet wheel in the event of wear. The ratchet wheel is coupled in rotation to an endless screw mounted around the aforementioned axis and meshing with a toothing of the take-up member. Thus, the rotation of said ratchet wheel causes the take-up member to move so as to compensate for wear.

The wear take-up member more particularly comprises:

a first annular element, one axial end of which has ramps inclined relative to the radial plane, intended to cooperate with counter-ramps of the pressure plate,

- a second element comprising a toothed part, fixed by riveting to the first element,

- a third element forming a balancing element, fixed by riveting to the first element and situated diametrically opposite with respect to the second element.

Such a take-up member is complex to produce and has a high cost.

The second element is engaged axially between lugs and a radial wall of the cassette, so as to hold it axially in position opposite the axis of the worm. This ensures an effective mesh between the toothed part and the worm.

The second element is capable of being elastically deformed so as to allow the axial movement of the first element in order to adapt to the axial movement of lifting or lowering of the pressure plate during the clutch or disengage phases.

The invention aims to provide an economical and easy to make alternative.

To this end, it offers a wear take-up member for a clutch mechanism, in particular for a motor vehicle, characterized in that it comprises:

a first annular element of axis X, one axial end of which comprises at least one ramp inclined relative to the radial plane, intended to cooperate with a counter-ramp of the clutch mechanism,

- A second element comprising a radially internal, annular part and a toothed part connected to the internal annular part, the second element being fixed to the first element.

The radially internal part of the second element makes it possible to ensure the centering of the take-up member, for example by cooperation with studs of a pressure plate of the clutch mechanism.

The studs may have come in one piece with the pressure plate. Alternatively, the studs can be added.

The toothed part is able to mesh with an endless screw actuated in the event of wear of a friction disc, so as to pivot the ramp relative to the corresponding counter-ramp.

The second element may include a balancing part diametrically opposite the toothed part relative to the axis X, connected to the internal annular part.

The balancing part makes it possible to limit or avoid unbalances so as to reduce vibrations in operation, when the wear take-up member is rotated with the rest of the clutch mechanism, around its axis.

The toothed part can be elastically deformable in the axial direction or displaceable axially relative to the first element.

In this way, it is possible to maintain the toothed part axially opposite the axis of the corresponding worm, said worm being axially fixed, while allowing axial movement of the first element carrying the ramps, so as to adapt to the axial movement of lifting or lowering the pressure plate during the clutch or disengage phases. Such an axial movement of the first element is for example between 1 and 5 mm.

The toothed part may include a median portion in the form of an arc of a circle of axis X, the radially outer edge of which comprises teeth, said median portion being connected, at its circumferential ends, to the annular internal part of the second element. , via radially extending connecting portions.

In other words, the toothed part is separated from the internal annular part of the second element by an opening or slot in the shape of an arc of a circle, of axis X. The circumferential ends of said opening or of said slot are delimited by the connecting portions extending radially.

Such a structure offers good axial elasticity to the toothed part, while being relatively simple.

The teeth can be oriented radially outwards.

The balancing part may comprise a middle portion in the form of an arc of a circle of axis X, said middle portion being connected, at its circumferential ends, to the annular internal part of the second element, by means of portions. radially extending link.

In other words, the balancing part is separated from the internal annular part of the second element by at least one opening or at least one slot in the form of an arc of a circle, of axis X. The circumferential ends of said opening or of said slot are delimited by the connecting portions extending radially. Alternatively, the balancing part can be separated from the internal annular part of the second element by a plurality of openings or a plurality of slots.

The internal annular part, the toothed part and / or the balancing part can extend in the same radial plane.

The assembly can therefore be easily produced during a step of cutting a metal sheet for example.

The toothed part can extend in a plane parallel to the plane formed by the internal annular part and the balancing part of the second element.

The first element may include notches opening at an axial end of the first element, the connecting portions of the toothed part and / or of the balancing part being engaged in the notches.

The notches can open out at the axial end of the first element comprising the ramps.

In this case, the connecting portions can be fixed in the notches by welding or by deformation of material at the circumferential ends of the notches, or by riveting at least one tab extending from at least one notch.

The wear take-up member may comprise, in section, in a plane passing through the axis X and cutting the wear take-up member at a notch, a T-shape, the first element and the second element being perpendicular to each other.

The T-shape brings radial stiffness to the wear take-up member and thus limits its ovalization.

The second element is thus fixed to the first element in a simple and inexpensive manner. In the case where the fixing is ensured by material deformation, this deformation can be obtained by crimping, at the corresponding ends of the notches, or by riveting a tab extending from the notch. Said tab can be engaged in a hole in the corresponding connecting part, the free end of the tab being deformed in the manner of riveting.

The first element can be produced from a strip resulting from the cutting of a metal sheet for example, said strip being bent or rolled so as to obtain a cylindrical ring of axis X, the ends of the strip then being welded l to one another. The weld bead can then be machined so as to obtain a surface finish in accordance with the specifications. Such a process, called rolled-welded process, is easy to implement and inexpensive.

The second element can be produced by cutting out a flat metal sheet.

The first element is for example made of mild steel, for example DC04 according to standard EN 10139.

The second element is for example made of pretreated steel such as a cold rolled spring steel, for example C60S according to the standard

NF EN 10132-4.

The invention also relates to a clutch mechanism, in particular for a motor vehicle, comprising

- a fixed cover,

- a pressure plate movable axially relative to the cover,

- a movable diaphragm between a engaged position and a disengaged position, capable of actuating the movement of the pressure plate,

wear take-up means comprising at least one wear take-up member of the aforementioned type, axially interposed between the diaphragm and the pressure plate, the ramp of said member cooperating with a counter-ramp of the mechanism, so that that the rotation of the ramp relative to the counter-ramp modifies the axial distance between the diaphragm and the pressure plate, and means for driving in rotation the wear take-up member, said drive means in rotation comprising at least one endless screw meshing with the toothed part of the wear take-up member.

The invention also relates to a device comprising a clutch mechanism of the aforementioned type, characterized in that it comprises a reaction plate, a friction disc interposed axially between the pressure plate and the reaction plate so as to be able to be clamped between the pressure plate and the reaction plate in the engaged position and so that it can be released in the disengaged position, the cover being fixed relative to the reaction plate.

The invention will be better understood and other details, characteristics and advantages of the invention will appear on reading the following description given by way of nonlimiting example with reference to the appended drawings in which:

FIG. 1 is an exploded perspective view of a clutch mechanism according to the invention,

FIG. 2 is a perspective view of the mechanism,

FIG. 3 is a perspective view, partially broken away, of the mechanism,

FIG. 4 is a view in axial section of the device,

FIG. 5 is a perspective view, from above, of a wear take-up member according to a first embodiment of the invention,

FIG. 6 is a sectional view along the plane P of the take-up member in FIG. 5,

FIG. 7 is a perspective view, from below, of the wear take-up member in FIG. 5,

FIGS. 8 and 9 are detailed views of the member of FIGS. 5 and 7, illustrating two stages of the crimping process of the connecting parts of the second element inside the notches of the first element,

FIG. 10 is a perspective view, from below, of a wear take-up member according to a second embodiment of the invention,

- Figures 11 to 13 are detailed views of the member of Figure 9, illustrating three stages of the riveting process of the connecting parts of the second element inside the notches of the first element.

Figures 1 to 9 show a clutch mechanism 1 with wear compensation according to a first embodiment of the invention. This comprises an annular fixed cover 2 of axis X, intended to be fixed on a reaction plate, an annular pressure plate 3 and movable along the axis X relative to the reaction plate 4 (FIG. 4) and to the lid

2. A friction disc 5 is intended to be interposed axially between the pressure plate 3 and the reaction plate 4.

The cover 2 has a generally hollow or bell shape. More particularly, the cover 2 comprises an annular part extending generally radially and a generally cylindrical part 7 extending from the radially external periphery of the radial part 6. The free end of the cylindrical part is fixed to the reaction plate 4 , for example by riveting or screwing at the level of radial flanges 8 of the cover 2.

The pressure plate 3 is housed in the internal volume of the cover 2.

A diaphragm 9 is mounted in the internal volume, said diaphragm comprising a deformable annular part 10, in the manner of a Belleville washer, from which actuating fingers 11 extend radially inwards. The radially inner periphery of the fingers 11 is able to cooperate with a clutch stop, as is known per se. The diaphragm 9 is mounted in abutment on the cover 2, at the support zones 12, and is held in abutment on said zones by means of hooks 13 which are fixed to the cover 2 by means of rivets 14.

The diaphragm 9 is used to actuate the pressure plate 3 between a fully engaged position in which said pressure plate 3 is pushed towards the reaction plate 4, so as to enclose the friction disc 5 between said plates 3, 4, and a disengaged position in which said pressure plate 3 is spaced from the reaction plate 4 so as to release the friction disc 5. For this purpose, elastic tongues 15 able to exert an axial force connect the cover 2 and the plate pressure 3. The tongues 15 are arranged so as to resiliently return the pressure plate 3 to its disengaged position.

Wear take-up means are interposed axially between the pressure plate 3 and the diaphragm 9. More particularly, the diaphragm 9 comes to cooperate with said wear take-up means in a zone located radially outside the zones of support 12 of said diaphragm 9 on cover 2.

These means comprise a movable wear take-up member 16 comprising a first annular element 17 of generally cylindrical shape, of axis X, comprising an axial end 18 against which the diaphragm 9 is capable of coming to bear, and an axial end 19 comprising ramps 20 oblique to the radial plane and extending circumferentially, cooperating with an associated counter-ramp 20a (FIG. 1), formed directly on the pressure plate 3.

By way of example, the angle of each ramp 20 of the take-up member and of the associated counter-ramp 20a of the pressure plate 3 is between 2 and 12 °.

The first element 17 has notches 21 opening out at the axial end 19 of the first element 17.

The take-up member 16 further comprises a second element 22 extending in a radial plane, comprising a radially internal annular part 23, a toothed part 24 connected to the internal annular part 23 and a balancing part 25 diametrically opposite to the toothed part 24 relative to the axis X, connected to the internal annular part 23.

The toothed part 24 has a middle portion in the form of an arc of a circle of axis X, extending angularly over an angular range of between 90 and 150 °, the radially outer edge of which has a toothed sector whose teeth 26 are oriented radially outward. Said middle portion is connected, at its circumferential ends, to the annular internal part 23 of the second element 22, by means of connection portions 27 extending radially. The toothed portion 24 is elastically deformable in the axial direction.

In other words, the toothed part 24 is separated from the internal annular part of the second element 22 by an opening or a slot 28 in the form of an arc of a circle, of axis X. The circumferential ends of said opening or of said slot 28 are delimited by the connecting portions 27 extending radially.

The balancing part 25 comprises a middle portion in the form of an arc of a circle of axis X, extending angularly over an angular range between 80 and 150 °. Said middle portion is connected, at its circumferential ends, to the annular internal part 23 of the second element 22, by means of connecting portions 27 extending radially, here three in number.

In other words, the balancing part 25 is separated from the internal annular part 23 of the second element 22 by at least one opening or at least one slot 28 in the form of an arc of a circle, of axis X.

The internal directory part 23, the toothed part 24 and / or the balancing part 25 extend in the same radial plane.

As a variant, the toothed part 24 extends in a plane parallel to the plane formed by the internal annular part 23 and the balancing part 25 of the second element 22. The two planes are offset axially.

The internal annular part 23 ensures centering of the take-up member 16, by cooperation with studs 29 of a pressure plate 3 (FIG. 4).

The connecting portions 27 of the toothed part 24 and of the balancing part 25 are engaged in the notches 21 of the first element 17.

As can be seen in FIG. 6, in a plane P passing through the axis X and cutting the wear take-up member 16 at a notch 21, the take-up member has, in section, a T-shape , the first element 17 and the second element 22 being perpendicular to each other.

The T-shape brings radial stiffness to the wear take-up member 16 and thus limits its ovalization.

In the embodiment of Figures 1 to 9, the connecting portions 27 are fixed in the notches 21 by material deformation 30 at the circumferential ends 31 of the notches 21. Such material deformation is obtained by crimping the first element 17 , at the corresponding ends of the notches, and makes it possible to fix the second element 22 on the first element 17. FIG. 7 illustrates a notch 21 and the corresponding connecting portion 27 before deformation of material, while FIG. 8 illustrates said notch 21 and said connecting portion 27 after deformation of material 30.

The second element 22 is thus fixed to the first element 17 in a simple and inexpensive manner.

The first element 17 is produced from a strip coming from the cutting of a metal sheet for example, said strip being bent or rolled so as to obtain a cylindrical ring of axis X, the ends of the strip then being welded l to one another. The weld bead can then be partially machined, for example by abrasion, so as to obtain a generally smooth surface. Such a process, called rolled-welded process, is easy to implement and inexpensive. The second element 22 can be produced by cutting out a flat metal sheet.

The first element 17 is for example made of mild steel, for example DC04 according to standard EN 10139.

The second element 22 is for example made of pretreated steel such as a cold rolled spring steel, for example C60S according to standard NF EN 10132-4. Such a material allows an axial deformation of the toothed part 24, in particular.

The toothed sector of the toothed part 24 forms a rack extending circumferentially, capable of cooperating with displacement means so as to be driven in rotation about the axis X, in the event of wear of the friction disc 5. The toothed sector is formed in a plane.

The displacement means comprise an endless screw 32 held in mesh with the rack of the toothed part 24. The endless screw 32 is coupled in rotation to a ratchet wheel 33 cooperating with a pawl 34 comprising an actuating lug 35 of which the free end engages the ratchet wheel 33 and the actuation of the free end of which is caused by wear of the friction disc 5.

The position of the ratchet wheel 33 relative to said free end of the tab 35 of the pawl 34 varies as a function of the wear of the friction disc and of the position of the pressure plate 3, so that the pawl 34 either capable of driving the ratchet wheel 33, in the event of wear of the friction disc 5, by displacement of the pressure plate 3 between its engaged and disengaged positions, as is known per se. The rotation of the ratchet wheel 33 thus results in the rotational movement of the take-up member 16 and therefore a modification of the axial distance between the bearing area and the pressure plate 3, due to the presence of the ramp 20 and the counter ramp 20a. This variation in distance compensates for the wear of the friction disc 5 if necessary.

The ratchet wheel 33 and the worm screw 32 are pivotally mounted about an axis 33a, the assembly being housed in a cassette 36. The cassette 36 is itself housed in a hollow zone 37 formed in the cylindrical part 7 cover 2.

The toothed part 24 is axially interposed between a radial base 38 of the cassette 36 and positioning lugs 39 of the cassette 36, so as to axially maintain in position the toothed part 24 facing the axis of the worm 32 , so as to guarantee an optimal meshing.

In operation, the pressure plate 3 is moved axially between its engaged and disengaged positions, causing with it the axial displacement of the first element 17 in particular of the take-up member 16. The toothed part 24, held axially, is therefore brought to be elastically deformed during the axial displacement of the pressure plate 3. It will be noted that the annular part 23 of the second element 22 is displaced axially with the first element 17.

The axial displacement of the pressure plate 3 between its engaged and disengaged positions is for example between 0.5 and 3 mm.

Figures 10 to 13 show a second embodiment, which differs from that explained with reference to Figures 1 to 8, in that the radial connecting portions 27 are fixed in the notches 21 by riveting. More particularly, each notch 21 has a lug 40 extending axially in the direction of the end 19 of the first element 17, each lug 40 passing through an opening 41 formed in the corresponding radial portion 27 of the second element 22, before being deformed or crimped at its end 42 in the manner of a riveting, to secure said connecting portion 27 in the notch 21.

According to another embodiment not shown, each connecting portion 27 of the second element 22 is welded in the notch 21.

Claims (13)

1. Wear take-up member (16) for a clutch mechanism (1), in particular for a motor vehicle, characterized in that it comprises: - A first annular element (17) of axis X, one axial end (19) of which comprises at least one ramp (20) inclined relative to the radial plane, intended to cooperate with a counter-ramp (20a) of the clutch mechanism (1), - a second element (22) comprising a radially internal annular part (23) and a toothed part (24) connected to the internal annular part (23), the second element (22) being fixed to the first element (17). 2. Wear take-up member (16) according to claim 1, in which the second element (22) comprises a balancing part (25) diametrically opposite the toothed part (24) relative to the axis X, connected to the internal annular part (23). 3. Wear take-up member (16) according to claim 1 or 2, in which the toothed part (24) is elastically deformable in the axial direction or displaceable axially relative to the first element (17). 4. Wear take-up member (16) according to claim 1 to 3, in which the toothed part (24) comprises a median portion in the form of an arc of a circle of axis X, the radially outer edge of which comprises teeth (26), said median portion being connected, at its circumferential ends , to the annular internal part (23) of the second element (22), by means of connecting portions (27) extending radially. 5. Wear take-up member (16) according to claim 4, in which the teeth (26) are oriented radially outwards. 6. Wear take-up member (16) according to one of claims 2 to 4, in which the balancing part (25) comprises a middle portion in the form of an arc of a circle with an X axis, said middle portion being connected, at its circumferential ends, to the annular internal part (23) of the second element (22), by means of connection portions (27) extending radially. 7. Wear take-up member (16) according to one of claims 1 to 5, in which the internal directory part (23), the toothed part (24) and / or the balancing part (25) s' extend in the same radial plane. 8. Wear take-up member (16) according to one of claims 1 to 5, in which the toothed part (24) extends in a plane parallel to the plane formed by the internal annular part (23) and the part balancing (25) of the second element (22). 9. Wear take-up member (16) according to one of claims 4 to 6, in which the first element (17) has notches (21) opening out at an axial end (19) of the first element (17), the connecting portions (27) of the toothed part (24) or of the balancing part (25) being engaged in the notches (21). 10. Wear take-up member (16) according to claim 9, in which the connecting portions (27) are fixed in the notches (21) by welding or by deformation of material at the circumferential ends (30) of the notches. (21), or by riveting at least one tab (40) extending from at least one notch (21). 11. Wear take-up member (16) according to claim 9 or 10, in which it comprises, in section, in a plane (P) passing through the axis (X) and cutting the wear take-up member. (16) at a notch (21), a T-shape, the first element (17) and the second element (22) being perpendicular to each other. 12. Clutch mechanism (1), in particular for a motor vehicle, comprising - a fixed cover (2), - a pressure plate (3) movable axially relative to the cover (2), - a diaphragm (9) movable between a engaged position and a disengaged position, capable of actuating the movement of the pressure plate 5 (3), - wear take-up means comprising at least one wear take-up member (16) according to one of claims 1 to 11, inserted axially between the diaphragm (9) and the pressure plate (3), the ramp (20) of said member (16) cooperating with a counter-ramp (20a) of the 10 mechanism (1), so that the rotation of the ramp (20) relative to the counter-ramp (20a) changes the axial distance between the diaphragm (9) and the pressure plate (3), and means for driving in rotation the wear take-up member (16), said means for driving in rotation comprising at least one worm (32) meshing with the part 15 tooth (24) of the wear take-up member (16). 13. Clutch device comprising a clutch mechanism (1) according to claim 12, characterized in that it comprises a reaction plate (4), a friction disc (5) interposed axially between the pressure plate ( 3) and the reaction plate (4) so that 20 able to be clamped between the pressure plate (3) and the reaction plate (4) in the engaged position and so as to be able to be released in the disengaged position, the cover (2) being fixed relative to the reaction plate (4) . 1/9