FR2886996A1 - Motor vehicle multiple clutch mechanism has one friction disc with hub in two coaxial sections for quicker assembly - Google Patents

Abstract

The multiple, and at least double, clutch mechanism (200), comprising at least one thrust plate (20) centered on a bearing, and at least two pressure plates (21, 22) to press friction discs (11, 212) against the thrust plate so it rotates a driven shaft (4, 5), has at least one of the friction discs (212) made with a hub in two coaxial sections - outer (241) and inner (242) - the inner one being movable along the lengthwise axis (X) of the clutch relative to the outer one. The two coaxial sections of the friction disc connect with one another through splined peripheral surfaces.

Description

The invention relates to a multiple clutch mechanism, in particular

  a dual clutch mechanism for a motor vehicle.

  The document FR 1,300,975 describes, for a connection between an internal combustion engine and a gearbox, a double clutch mechanism comprising a central support plate on either side of which is mounted a clutch mechanism whose pressure plate squeezes a friction disk against said central support plate. The latter is mounted centered on the end of the outer shaft driven with a ball bearing. The latter is trapped between the two friction discs. This has the disadvantage of requiring to mount the double clutch mechanism on the driven shafts, therefore on the gearbox element by element of said mechanism, which increases the online assembly time and the risk of error, and by therefore the production costs.

  An object of the invention is to provide a mechanism of multiple clutches having a structure for a simple and fast mounting on a gearbox.

  For this purpose, it is provided, according to the invention, a multiple clutch mechanism for a motor vehicle comprising at least one support plate centered on a bearing, at least two pressure plates, each able to clamp against the plate of a friction disc that can drive a driven shaft, one of the friction discs further comprising a hub in two parts, internal and external, coaxial and removable relative to each other.

  Thus, the clutch mechanism is provided completely pre-assembled in the form of a module and the internal part can be put in place later, leaving free access to the elements that it is likely to imprison, once in place, as the bearing of the support plate which it is then possible to ensure the implementation of assembly.

  Advantageously but optionally, the clutch device 10 has at least one of the following features.

  the mechanism comprising an axis of rotation X, the inner portion is adapted to perform a translational movement along the X axis relative to the outer portion, the inner portion has longitudinal grooves along the X axis on a radially outer periphery apt to cooperate with complementary grooves of a radially inner periphery of the outer part, the outer part has a shoulder at a radially inner periphery, the shoulder is formed of a sheet bonded to the outer part, the sheet comprises friction linings at a radially outer periphery, the sheet is in the form of a ring and is connected to the external part at the radially inner periphery of the outer part, the mechanism comprises means for holding the part internal to the outer part, the mechanism comprises a torsion damper, and the mechanism comprises a flexible sheet.

  It is also provided, according to the invention, a method of mounting a double clutch mechanism having at least one of the above features on driven shafts comprising steps of: - engagement of a module on one of the driven shafts, the module comprising at least the support plate and the centering bearing, the pressure plates, the outer part of one of the friction discs, the other friction discs, - installation of a means for holding the centering bearing through an inside of the outer part, engaging the inner part with the outer part and the other one of the driven shafts, and - setting up a means for holding the inner part by compared to the external part.

  Other features and advantages of the invention will appear in the description below of a preferred embodiment and variants. In the accompanying drawings.

  Figure 1 is a half sectional view of a first embodiment of a double clutch mechanism; Figure 2 is a half sectional view of a second embodiment of a dual clutch mechanism; Figure 3 is a half sectional view of a first embodiment according to the invention; Figure 4 is a half sectional view of a variant of the first embodiment of Figure 3; and FIG. 5 is a partially exploded half-sectional view illustrating a manner of assembling the embodiment of FIG. 4.

  It is understood by hub, the radially inner part of a part or a set of parts able to rotate about an axis.

  Referring to Figure 1, we will describe a first embodiment of a double clutch mechanism. A multiple clutch mechanism 1 is, here, a double clutch comprising three plates 20, 21 and 22. The whole of this mechanism has an axis of rotation X. On the one hand, the double clutch mechanism 1 is linked to a driving shaft 3, such as for example the end of a crankshaft of a combustion engine of a motor vehicle. In the embodiment of FIG. 1, this connection is made by screwing a flexible sheet metal 37 using a series of fastening means 38 (here bolts) distributed substantially around a circumference about the axis. rotation X at an inner periphery of the flexible sheet.

  On the other hand, the double clutch mechanism 1 is connected to two driven shafts 4, 5, such as the input shafts of a gearbox. The two driven shafts 4, 5 are here coaxial, one of the shafts then being called the outer shaft 5 and the other, the inner shaft 4. Each of these driven shafts 4, 5 have, at one end located on the mechanism side double clutch 1, longitudinal grooves adapted to receive, in a translation movement along the axis X, a hub 41, 42 respectively, of friction disk 12, 11 respectively, which has a bore having complementary longitudinal grooves .

  The friction discs 11, 12 comprise, at a radially outer periphery, friction linings mounted on either side of a gland of the friction disc. At their lining, each friction disk 11, 12 is adapted to be clamped against a support plate 20 by a pressure plate 22, 21 respectively. The pressure plates 21, 22 are movable in translation along the X axis of the double clutch mechanism. The support plate 20 is located between the two friction discs 11, 12 and is fixed in translation along the axis X. It is mounted on the end of the outer shaft 5 with a bearing 44 (here, a bearing ball) retained, once mounted on the outer shaft 5, by a shoulder opposite side of said end, on the one hand, and, secondly, by a circlip 47 on the other side.

  In addition, a radially inner portion of the support plate has a series of openings 43 uniformly distributed over a circumference about the axis X. These openings 43 can improve the cooling of the support plate by creating a forced ventilation of the latter when the double clutch mechanism is in operation.

  On a radially outer periphery, the support plate 20 has extensions extending radially outwards at which a cover 2, 36 can be fixed, for example by screwing with bolts 46. Here, the cover is two parts 2, 36, mounted on either side of the support plate 20. Each of the parts 2, 36 covers a clutch, and is sheet metal.

  Part 2 of the cover carries the pressure plate 22 of the clutch located on the side of the driven shafts 4, 5. The connection between the two is effected by means of a series of elastically deformable tongues 70, one end of which is connected to the part 2 of the lid (by riveting, for example) and the other end is connected to the pressure plate 22 (by riveting, for example). In the absence of a clutch force greater than an elastic return force of these tongues, the latter allow to bring and maintain the pressure plate 22 in a disengaged position, the friction disc 11 is then tighter between the pressure plate 22 and the support plate 20.

  Conversely, in the engaged position, the tongues 70 are then elastically deformed and the pressure plate 22 clamps the friction disk 11 against the support plate 20 under the effect of a clutch force provided by a stop 8 and transmitted with a lever arm to the pressure plate 22 by a diaphragm 9 linked hinged to the portion 2 of the cover by a hinge 60. The actuation of the stop 8 is known per se: it can be mechanical or hydraulic or pneumatic.

  The portion 36 of the cover carries the pressure plate 21 of the clutch located on the side of the driving shaft 3. The connection between the pressure plate 21 and the portion 36 of the cover, as before, using deformable tongues resiliently 71, one end is connected to the portion 36 of the cover (by riveting, for example) and the other end is connected to the pressure plate 21 (by riveting, for example). Similar to the preceding tabs 70, from an elastically deformed state to an undistorted state of rest, the tongues 71 make it possible to bring and maintain the pressure plate 21 in a disengaged position, the friction disk 12 'then being tighter between the pressure plates 21 and support 20.

  Conversely, in the engaged position, the pressure plate 21 squeezes the friction disk 12 against the support plate 20 under the effect of a clutch force, the tongues 71 being in an elastically deformed state. The clutch force is provided by the stop 7 and is transmitted with a lever arm to the pressure plate 21 by a diaphragm 10 hinged to the lid 36 by a hinge 61.

  The actuation of the abutment 7 is achieved by a rod 6 coaxially traversing the inner shaft 4 which is then hollow. Unrepresented actuating means of this rod 6 may be mechanical or hydraulic or pneumatic and are known per se.

  The portion 36 of the cover extends radially towards the axis of rotation to form a radially inner periphery. This radially inner periphery is adapted to receive a series of connecting means 72 distributed over a circumference having a value of radius R. This value is substantially equal to or greater than about half (+/- 20%) of a radius value. 2R a radially outer periphery of the dual clutch mechanism 1. The radially inner periphery of the portion 36 of the cover has a radius value substantially less than the value R. This difference in value can be of the order of 5 to 20 % about. In general, the value R is greater than a value of a radius of the distribution circumference of the fastening means 38 (here, bolts).

  The connecting means 72 make it possible to bind the cover 2, 36 to a web 35 of a torsion damper 30. The web 35 has a radially inner periphery having a radius value equal to about the value R. The subassembly comprising by the web 35, on the one hand, and the cover 2, 36, on the other hand, forms a mass, called secondary mass, for the torsion damper 30.

  Another mass, called the primary mass of the torsion damper, is formed by two guide washers 31, 32, as well as a starter ring 45. The two guide washers 31, 32 are mounted on both sides. other of the web 35 in an axial direction of axis X. The guide ring 32, located on the side of the driven shafts 4,5, has a radially inner periphery whose radius value is greater than the value R. Thus, the means 72 are radially inside the guide washer 32.

  In addition, the web 35 is capable of effecting a relative rotational movement about the axis X with respect to these two guide washers 31, 32. This relative rotational movement is effected against elastic means 34 capable of to store energy during deformation. Here, the elastic means 34 are compression springs. During the relative rotational movement of the guide washers relative to the web, the springs 34 are more or less compressed depending on the torque to be transmitted between the guide rings and the web. This operation of the torsion damper is known per se. The compression springs 34 are located at a radially outer periphery of the torsion damper.

  This arrangement makes it possible, on the one hand, to have greater angular deflections between the sail and the guide washers, and, on the other hand, to make it possible not to occupy a volume at the hub of the shock absorber. torsion. Thus, with such a structure, the torsion damper 30 has a partially recessed hub. This allows, during operation of the double clutch mechanism, a greater possible stroke for the stop 7 and, therefore, the end of the fingers of the diaphragm 10. The latter can then be configured to have an arm ratio of bigger lever. On the other hand, it should be noted that large angular deflections allow operation of the optimized torsion damper ensuring better filtration of vibrations. The two guide washers are connected to one another at their radially outer periphery, here by welding.

  The torsion damper 30 comprises centering pins 39, for axially centering along the axis X, the web 35 between the two guide rings 31, 32. The pins 39 are uniformly distributed over a circumference in pairs, each counter of the pair being fixed on the guide ring 31, 32 respectively, facing one another.

  The torsion damper 30 further comprises circular seals 40 capable of forming a seal between the web 35 and the guide rings 31, 32. Thus, grease may be provided at the compression springs 34 in order to improve their operation when the whole of the double clutch mechanism 1 rotates. Here, the seals 40 are held in place by means of the fastening means 72.

  In addition, the torsion damper comprises a so-called sliding friction system 50. This friction system is located between the guide washer 31 and the web 35 and allows energy to be dissipated when the web rotates relative to the web. guide washer. For some applications, this friction system can be removed.

  At a radially outer periphery, the flexible sheet 37 is rigidly connected to one of the guide rings 31 of the torsion damper 30.

  A role of the flexible sheet 37 is to absorb the misalignments between the driving shaft 3 and driven shafts 5,4. Misalignments can be angular, axial or radial.

  A role of the bearing 44 is to allow the recovery of the clutch forces of the two clutches, as well as the centering of the support plates assembly 20 and 21,22, cover 2,36 and sail 35.

  We will now describe a method of assembling the embodiment of a dual clutch mechanism that has just been described in the context of use between an internal combustion engine and a gearbox. In general, a first part of the double clutch mechanism 1 is mounted on the combustion engine, a second part being mounted on the gearbox. The two parts are then assembled during a motor-explosion / gearbox assembly.

  The torsion damper 30 and the clutch mechanism on the engine side (cover 36, pressure plate 21, diaphragm 10, stop 7, tongues 71) are screwed onto the crankshaft (driving shaft 3) via the sheet metal. flexible 37, as previously described.

  Side gear box, a subset formed of the box-side mechanism (cover 2, pressure plate 22, diaphragm 9, tabs 70), the associated friction disc 11 and the support plate 20 is mounted on the gearbox the grooves of the hub 42 of the friction disc 11 engage those of the outer shaft 5, the bearing 44 of the support plate 20 is fitted on the outer shaft to the shoulder, the circlip 47 is mounted, now axially bearing 44 against the shoulder.

  The second friction disc 12 is then engaged on the inner shaft 4 similarly to the first friction disc 11.

  When the combustion engine and the gearbox are approached from one another, unrepresented pins and fixed on the support plate 20 allow the centering portion of the engine side up to explosion side compared to that mounted side gearbox. The two parts are then screwed to one another with nuts not shown and fixed on the cover 36 for this purpose (by welding for example).

  Referring to Figure 2, we will describe a second embodiment of a dual clutch mechanism. Only the differences with the first embodiment previously described are discussed.

  The support plate 120 located between the two clutches of the double clutch mechanism 100 comprises a hub 121 in sheet on which the support plate 120 itself is connected in itself. The connection is made here by means of rivets 122. This sheet forming the hub 121 may have flexibilities. The latter allow the swiveling of the support plate 120 (and therefore the swiveling of the secondary mass of the torsion damper 130 described below which the support plate 120 is part) to absorb angular misalignments between the driving shaft 3 and the driven shafts 4, 5. In addition, the plate forming the hub 121 is mounted on the outer shaft 5 via a bearing 144, which may be a needle bearing or a smooth bearing. Here, the end of the outer shaft 5 is fitted around the hub 121.

  The torsion damper 130 is structurally very close to the torsion damper 30 of the embodiment of FIG. 1. The two guide rings 131, 132 frame the web 135 while being able to perform a relative rotational movement through report to said sail 135, and this against the elastic means 34. The latter are able to store energy during deformation. In addition, axial bearings 139 are placed between the web 135 and each of the guide washers 131, 132. These bearings 139 allow a recovery of clutch forces of the two clutches. The bearings 139 may be plain bearings or needle bearings. Seals 140 are provided for the same reasons as seals 40 of the previous embodiment.

  In addition, the guide washer 131 is directly connected to the driving shaft 3, here by screwing with bolts 38 forming the fastening means.

  Concerning the mounting of the double clutch mechanism 100 for use between an internal combustion engine and a gearbox, the double clutch mechanism is mounted completely on the engine and then guided on the gear shafts.

  In a first case, the double clutch mechanism 100 is a single module. The fixing bolts 38 are retained in place, before mounting on the driving shaft 3. The various components of the mechanism 100, in particular the diaphragms, the friction disk hubs, the hub of the support plate 120, are arranged so as to allow the passage of a tool for screwing bolts 38 on the drive shaft 3. Such an arrangement may be unrepresented openings.

  In a second case, the double clutch mechanism 100 is formed of 3 subassemblies: - 1: the torsion damper and the clutch mechanism on the engine side - 2: the friction disc 12 associated with the mechanism of clutch on the engine side - 3: the support plate 120, the second friction disk and the clutch mechanism on the gearbox side.

  The guide washer 131 is screwed into the drive shaft by means of the bolts 38 (positioning of the subassembly 1). Then the first friction disk (subassembly 2) is positioned on the pressure plate of the clutch mechanism on the engine side (a centering tool of the friction disk can be used). Then, the subassembly 3 is screwed onto the cover of the clutch mechanism on the engine side in a manner similar to the assembly of the two parts of the previous embodiment of FIG.

  Finally, during the assembly of the gearbox and the internal combustion engine, the grooves of the hub of the first friction disc 12 are engaged on those of the inner shaft 4. The bearing 144 is engaged in the outer shaft 5 the splines of the hub of the second friction disc 11 on those of the outer shaft 5.

  Referring to Figure 3, we will describe a first embodiment of the invention illustrated by a double clutch mechanism 200. Again, only the differences with the two previous embodiments of a dual clutch mechanism will be discussed .

  The torsion damper 230 is structurally almost identical to the torsion damper 30 of FIG. 1, except the ring 239 situated between the web 35 and the second guide washer 32. This ring 239 has a similar role to that of the pins 39 of the first embodiment of a double clutch mechanism.

  The first friction disc 212 is formed of three main parts: - a trim ring 213 carrying the pair of friction liners - a first portion 241 of radially outer hub on which is attached the trim ring 213 (here by riveting a second portion 242 of radially inner hub.

  The gland 213 is extended radially towards the axis X along a face of the first part 241 of the hub to protrude from a radially inner periphery of the first part 241 of the hub to form an axial shoulder of 'stop.

  In FIGS. 4 and 5, a variant of the embodiment of FIG. 3 is illustrated. Here, the trim carrier 313 of the first friction disc 312 does not extend along one face of the first portion 341 of the hub. to come form a shoulder as previously described. This axial shoulder is formed by a sheet metal ring 344 connected to the first part 341 of the hub, here by riveting, and protruding from the radially inner periphery of said first part 341.

  On the other hand, in this variant embodiment 300, the stop actuating the clutch mechanism on the driving shaft side 3 is in two parts: a cup 307 able to be actuated by the actuating rod 6, and bearing means 308 adapted to be mounted on the radially inner free ends of the fingers of the diaphragm 310. During an assembly, the bearing means 308 are clipped onto the cup 307. The assembly then forms a clispable stop whose operating mechanism is known in itself.

  Such a structure of the first friction disc 212, 312 will allow to mount the assembly of the double clutch mechanism 200, 300 on the driven shafts 4, 5, in particular on the gearbox in the context of use between a engine and a gearbox. Only the flexible sheet is mounted on the driving shaft 3 before assembling the gearbox to the combustion engine.

  The double clutch mechanism 200, 300 without the cup 7, 307 and the second portion 242 of the hub of the first friction disc 212, 312 is mounted in the form of a single module on the gearbox: - the splines of the hub of the second friction disk on the gearbox side are engaged with those of the outer shaft 5, the bearing 44 is engaged on the end of the outer shaft 5 until it stops on the shoulder, the circlip 47 is set up and axially maintains the bearing 44 - the second portion 242 of the hub is engaged both on the inner shaft and on the first part 241, 341 of the hub, the two engagement being effected by fluting, until to come into abutment on the shoulder 213, 344, - a circlip 243, 343 is put in place to axially maintain the second part of the hub on the first part of the hub, - the cup 7, 307 is put in place The assembly final engine / gearbox is made by screwing the flexible sheet onto the guide washer on the engine side at its radially outer periphery as shown in FIG.

  As we have seen, the embodiments that have been previously described comprise a torsion damper 30, 130, 230 having a structure allowing to leave a large volume at the hub.

  This free volume allows the abutment 7, 307, 308 to achieve large amplitudes of movement in translation along the X axis, on the one hand, and, on the other hand, to use a diaphragm having long fingers extending radially towards said axis X. Thus, the force of the abutment 7, 307, 308 is transmitted to the pressure plate via the diaphragm with a large lever ratio. This large lever makes it possible to have a relatively low abutment force for a clamping force of the friction disk by the given pressure plate allowing the passage of a predetermined torque. Consequently, the effort that the actuator must provide to the abutment is reduced. The latter is then more economical to achieve (because of reduced size) and more economical in use (because of reduced power).

  Another advantage of such a structure is that there is always sufficient abutment travel when the friction linings wear out and therefore reduce in thickness, thereby increasing the travel of the pressure plate during tightening. friction disc.

  The clutches of the dual clutch mechanism 1, 100, 200, 300 may both be normally open, or both normally closed, or one normally open and the other normally closed.

  Of course, it is possible to bring to the invention many modifications without departing from the scope thereof.

Claims (11)

  1. Multiple clutch mechanism (200; 300) for a motor vehicle comprising at least one bearing plate (20) centered on a bearing (44), at least two pressure plates (21, 22), each capable of tightening against the support plate a friction disc (11,212; 312) which can drive a driven shaft (4,5), characterized in that one (212; 312) of the friction discs has a hub in two parts (241,242 341), internal and external, coaxial with each other.   2. Mechanism according to claim 1, characterized in that, the mechanism having an axis of rotation X, the inner portion is adapted to perform a translational movement along the axis X relative to the outer portion.   3. Mechanism according to claim 2, characterized in that the inner portion (242) comprises longitudinal grooves along the X axis on a radially outer periphery adapted to cooperate with complementary splines of a radially inner periphery of the outer portion ( 241; 341).   4. Mechanism according to one of the preceding claims, characterized in that the outer portion has a shoulder at a radially inner periphery.   5. Mechanism according to claim 4 characterized in that the shoulder is formed of a sheet (213; 344) connected to the outer part.   6. Mechanism according to claim 5, characterized in that the plate (213) has friction linings (212) at a radially outer periphery.   7. Mechanism according to claim 6, characterized in that the plate (344) is ring-shaped and is connected to the outer part at the radially inner periphery of the outer part.   8. Mechanism according to one of claims 1 to 7, characterized in that it comprises holding means (243, 343) of the inner portion relative to the outer portion.   9. Mechanism according to one of claims 1 to 8, characterized in that it comprises a torsion damper (230).   10. Mechanism according to one of claims 1 to   9, characterized in that it comprises a flexible sheet (37).   11. A method of mounting a double clutch mechanism according to one of claims 1 to 10 on 15 driven shafts (4,5) comprising steps of: engaging a module on one (5) trees carried out, the module comprising at least the support plate and the centering bearing, the pressure plates, the outer part of one of the friction discs, the other friction discs, setting up a means of maintaining (47) the centering bearing through an interior of the outer portion, engaging the inner portion with the outer portion and the other (4) of the driven shafts, and providing a holding means (243 343) of the inner part with respect to the outer part.