JP2005195099A - Clutch cover assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain thermal deformation of a pressure plate even though friction between a pressure face of the pressure plate and a friction connecting section of a clutch disk is generated in a clutch cover assembly. <P>SOLUTION: The clutch cover assembly 4 comprises a clutch cover 41, the pressure plate 42, and a diaphragm spring (pressure member) 43. The clutch cover 41 is fixed on a flywheel 2 at a friction face 21 side of the flywheel 2. The pressure plate 42 is mounted on the clutch cover 41 in a relatively irrotatable state. A pressure face 44 pushing the friction connecting section 32 is arranged on one face of the pressure plate 42, and a groove 45 extending to a radial direction is formed on the pressure face 44. The diaphragm spring 43 is supported by the clutch cover 41. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a clutch cover assembly, and more particularly to a clutch cover assembly for engaging a clutch by pressing a friction coupling portion of a clutch disk against a friction surface of a flywheel.

  BACKGROUND ART A vehicle clutch device is a device that is connected to an engine crankshaft and a transmission main drive shaft, and transmits and shuts off torque from the engine to the transmission. The clutch device is attached to, for example, a flywheel fixed to the tip of a crankshaft, a clutch disk assembly having a clutch disk including a friction coupling portion disposed in proximity to a friction surface of the flywheel, and the flywheel. A clutch cover assembly that presses the friction coupling portion of the clutch disk against the friction surface of the flywheel, and a clutch operation mechanism that applies an operation load to the clutch cover assembly to perform clutch operation are provided. The clutch operation mechanism is composed of, for example, a hydraulic cylinder, and is composed of an annular housing fixed to the wall surface of the transmission housing, and a piston disposed so as to be movable in the axial direction therein. The piston can apply an operation load to a part of the clutch cover assembly, and moves in the axial direction when hydraulic pressure is supplied from the outside to the oil chamber in the annular housing.

In general, a clutch cover assembly is used for clutch engagement by pressing a friction coupling portion of a clutch disk against a friction surface of a flywheel, and includes a clutch cover, a pressure plate, and a diaphragm spring (pressing member). (Patent Document 1). The clutch cover is fixed to the flywheel on the friction surface side of the flywheel. The pressure plate is for pressing the friction coupling portion of the clutch disc against the friction surface of the flywheel. The pressure plate is attached to the clutch cover so as not to rotate relative to the clutch cover, and is disposed in the vicinity of the friction coupling portion of the clutch disk. The pressure plate is formed with a pressing surface capable of pressing the friction coupling portion of the clutch disk. The pressing surface abuts on the friction coupling portion of the clutch disk to press the friction coupling portion, whereby the friction coupling portion of the clutch disk is pressed against the friction surface of the flywheel. The diaphragm spring is for pressing the pressure plate toward the friction surface of the flywheel, and is supported by the clutch cover. Here, an operation load of the clutch operation mechanism is applied to the diaphragm spring.
JP-A-9-250560

  In the conventional clutch cover assembly, in order to press the friction coupling portion of the clutch disc against the friction surface of the flywheel, the pressing surface of the pressure plate comes into contact with the friction coupling portion of the clutch disc and presses the friction coupling portion. ing. When the pressing surface of the pressure plate comes into contact with the friction coupling portion of the clutch disk, a very large friction is generated between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk, so that the pressure plate expands due to frictional heat. It becomes easy to heat deform. In addition, when the pressure plate pressing surface presses the friction coupling portion of the clutch disk, even if a transient fluctuation acts between the pressure plate pressing surface and the clutch disk friction coupling portion, the pressure plate A very large friction is generated between the pressing surface and the frictional connection portion of the clutch disk, and the pressure plate is easily expanded by frictional heat and easily deforms. When the pressure plate expands due to frictional heat and is thermally deformed, the contact state between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk becomes non-uniform, and the pressure plate and the clutch disk may slip. In particular, when excessive frictional heat acts on the pressure plate, the pressure plate may partially yield and become plastic. Once a certain portion of the pressure plate is plasticized, residual deformation occurs in the pressure plate even if the frictional heat of the pressure plate cools down. Then, regardless of whether the pressure plate is thermally deformed by frictional heat, the contact state between the pressure plate pressing surface and the clutch disk friction coupling portion becomes unstable, and the pressure plate and the clutch disk may slip. There is.

  It is an object of the present invention to suppress thermal deformation of a pressure plate in a clutch cover assembly even if friction is generated between a pressing surface of a pressure plate and a friction coupling portion of a clutch disk. It is in.

  The clutch cover assembly according to the first aspect is for engaging the clutch by pressing the friction coupling portion of the clutch disk against the friction surface of the flywheel. The clutch cover assembly includes a clutch cover, a pressure plate, and a pressing member. The clutch cover is fixed to the flywheel on the friction surface side of the flywheel. The pressure plate is for pressing the friction coupling portion of the clutch disc against the friction surface of the flywheel, and is attached to the clutch cover so as not to be relatively rotatable. A pressure surface that presses the friction coupling portion is provided on one surface of the pressure plate, and a groove portion is formed on the pressure surface. The pressing member is for pressing the pressure plate against the friction surface side of the flywheel, and is supported by the clutch cover.

  In this clutch cover assembly, the clutch cover is fixed to the flywheel on the friction surface side of the flywheel. Then, in a state where the pressing member is supported by the clutch cover, the pressure plate mounted on the clutch cover so as not to be relatively rotatable is pressed against the friction surface side of the flywheel. At this time, the pressure plate presses the friction coupling portion of the clutch disk on the pressing surface where the groove portion extending in the radial direction is formed. The friction coupling portion of the clutch disk pressed against the pressing surface is pressed against the friction surface of the flywheel.

  Here, in order to press the friction coupling portion of the clutch disk against the friction surface of the flywheel, the pressing surface of the pressure plate presses the friction coupling portion of the clutch disk. At this time, since the groove portion is formed on the pressing surface of the pressure plate, even if friction occurs between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk, the groove portion restricts the thermal expansion of the pressure plate. Can be relaxed. That is, the thermal deformation of the pressure plate can be suppressed by the groove formed on the pressing surface of the pressure plate. As described above, if the groove portion can suppress the thermal deformation of the pressure plate, the pressure plate is hardly plasticized, and the pressure plate is less likely to be deformed.

  According to a second aspect of the present invention, in the clutch cover assembly according to the first aspect, the pressure plate is formed in an annular shape. The groove portion is formed to extend in the radial direction at least at a part from the inner peripheral end to the outer peripheral end of the pressing surface of the pressure plate, and a plurality of the groove portions are arranged at intervals in the circumferential direction. In this case, a plurality of groove portions are arranged at intervals in the circumferential direction in at least a part from the inner peripheral end to the outer peripheral end of the pressing surface. Thereby, even if friction arises between the pressing surface of a pressure plate and the frictional connection part of a clutch disc, the restriction | limiting with respect to the thermal expansion of a pressure plate can be relieve | moderated by a groove part. That is, the groove portion can suppress thermal deformation of the pressure plate. Further, the frictional heat of the pressure plate can be radiated in the groove portion. At this time, if the groove is formed only at a position where the thermal expansion in the circumferential direction of the pressure plate is large and the groove is not formed at a position where the thermal expansion in the circumferential direction of the pressure plate is small, the pressure surface of the pressure plate It is possible to suppress a decrease in the strength and rigidity of the pressure plate due to the formation of the groove portion. Further, the abrasion powder that may be generated between the pressure plate pressing surface and the clutch disk frictional connection is retained in the groove when the clutch is engaged, and from the groove when the clutch is released. It can be discharged to the outside. Here, for example, if the groove formed in the pressure plate is formed to the outer peripheral end side, even if the clutch is not disengaged, the abrasion powder is removed from the groove in the radial direction by centrifugal force during rotation of the pressure plate. Can be discharged outward. As described above, if the wear powder is allowed to stay in the groove portion so that the wear powder can be discharged from the groove portion, the wear powder is interposed between the pressure plate pressing surface and the clutch disk friction coupling portion. This makes it difficult to maintain a stable contact state between the pressure plate pressing surface and the frictional connecting portion of the clutch disc.

  The pressure plate includes, for example, a protrusion used when the pressing member presses the pressure plate against the friction surface of the flywheel and a strap plate that urges the pressure plate in a direction away from the flywheel. A protrusion or the like for mounting may be formed. In consideration of the influence of these protrusions, the grooves extending in the radial direction on the pressing surface are formed at equal or unequal intervals, thereby suppressing thermal deformation of the pressure plate, radiating the frictional heat of the pressure plate, pressure plate In some cases, it is possible to improve the effects of suppressing the decrease in strength and rigidity, and discharging wear powder from the groove.

  According to a third aspect of the present invention, in the clutch cover assembly according to the second aspect, the groove portion includes a first radial groove portion formed between the inner peripheral end and the outer peripheral end to the outer peripheral end on the pressing surface. ing. In this case, even if friction is generated between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk, the first radial groove portion is not restrained by the outer peripheral end, and the restraint against the thermal expansion of the pressure plate is the first. It can relieve with a radial groove part and can suppress the thermal deformation of a pressure plate. If the first radial groove is formed from the inner peripheral end to the outer peripheral end to the outer peripheral end, the wear powder is retained in the first radial groove due to the centrifugal force when the pressure plate rotates. It can be discharged radially outward from the radial groove. As described above, if the wear powder is allowed to stay in the first radial groove portion so that the wear powder can be discharged from the first radial groove portion, the pressure plate between the pressure plate pressing surface and the frictional connection portion of the clutch disk is provided. Wear powder is less likely to intervene, and the contact state between the pressure plate pressing surface and the clutch disk friction coupling portion can be stably maintained.

  According to a fourth aspect of the present invention, in the clutch cover assembly of the second or third aspect, the groove has a second radial groove formed on the pressing surface from the inner peripheral end to the outer peripheral end. In this case, even if friction is generated between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk, the second radial groove portion is not restrained by the inner peripheral end and the outer peripheral end, and the thermal expansion of the pressure plate is performed. Can be relaxed by the groove, and thermal deformation of the pressure plate can be suppressed. Further, if the second radial groove is formed from the inner peripheral end to the outer peripheral end, an air flow radially outward is formed in the second radial groove due to the centrifugal force when the pressure plate rotates. Therefore, the frictional heat of the pressure plate can be radiated from the second radial groove. And the abrasion powder which may be generated between the pressing surface of a pressure plate and the frictional connection part of a clutch disk can be made to stay in a 2nd radial groove part, and can be discharged | emitted radially outward from a groove part. As described above, if the wear powder is allowed to stay in the second radial groove portion and can be discharged from the second radial groove portion, the pressure plate between the pressure plate and the frictional connection portion of the clutch disk is provided. Wear powder is less likely to intervene, and the contact state between the pressure plate pressing surface and the clutch disk friction coupling portion can be stably maintained.

  In the clutch cover assembly according to a fifth aspect, in the clutch cover assembly according to any one of the second to fourth aspects, the groove portion extends linearly in the radial direction. In this case, the constraint on the thermal expansion of the pressure plate can be relaxed by the plurality of groove portions, and the groove portions can be easily formed on the pressing surface of the pressure plate. In addition, the wear powder can be retained in the groove portion extending linearly in the radial direction on the pressing surface, and the wear powder can be discharged from the groove portion. For example, when the groove extending linearly in the radial direction on the pressing surface is formed up to the outer peripheral end side, the abrasion powder stays in the groove due to the centrifugal force during the rotation of the pressure plate and moves radially outward from the groove. Can be discharged. On the other hand, for example, in the case where a groove extending linearly in the radial direction on the pressing surface is formed to penetrate from the inner peripheral end to the outer peripheral end of the pressing surface, the groove is outside in the radial direction according to the rotation of the pressure plate. Since the air flow toward the direction is formed, the frictional heat of the pressure plate can be radiated from the groove when the pressure plate rotates. And the abrasion powder which may arise between the pressing surface of a pressure plate and the frictional connection part of a clutch disk can be made to stay in a groove part, and can be discharged | emitted from a groove part to radial direction outward effectively.

  In the clutch cover assembly according to a sixth aspect, in the clutch cover assembly according to any one of the second to fourth aspects, the groove portion extends linearly at a predetermined angle with respect to the radial direction. In this case, the constraint on the thermal expansion of the pressure plate can be relaxed by the plurality of groove portions, and the groove portions can be easily formed on the pressing surface of the pressure plate. Further, the wear powder can be retained in the groove portion inclined at a predetermined angle with respect to the radial direction on the pressing surface, and the wear powder can be discharged from the groove portion. For example, when a groove portion inclined at a predetermined angle with respect to the radial direction on the pressing surface is formed up to the outer peripheral end side, the abrasion powder is retained in the groove portion by the centrifugal force when the pressure plate rotates, and the groove portion radially extends from the groove portion. Can be discharged outward. On the other hand, for example, when a groove portion inclined at a predetermined angle with respect to the radial direction on the pressing surface is formed from the inner peripheral end to the outer peripheral end of the pressing surface, the groove portion has a radial direction in accordance with the rotation of the pressure plate. Since the outward air flow is likely to be formed, the effect of dissipating the frictional heat of the pressure plate from the groove and the wear powder that may be generated between the pressure plate pressing surface and the frictional connection of the clutch disk from the groove. The effect of discharging outward in the radial direction can be improved.

  In the clutch cover assembly according to a seventh aspect, in the clutch cover assembly according to any one of the second to fourth aspects, the groove portion extends in the radial direction with a curvature. In this case, the constraint on the thermal expansion of the pressure plate can be relaxed by the plurality of grooves. Further, the wear powder can be retained in the groove portion having a curvature on the pressing surface, and the wear powder can be discharged from the groove portion. For example, when the groove portion having a curvature on the pressing surface is formed up to the outer peripheral end side, the abrasion powder can be retained in the groove portion and discharged radially outward from the groove portion by centrifugal force when the pressure plate rotates. it can. On the other hand, for example, when a groove having a curvature on the pressing surface is formed from the inner peripheral end to the outer peripheral end of the pressing surface, the air flow toward the radially outward direction in response to the rotation of the pressure plate Since the frictional heat of the pressure plate is dissipated from the groove during rotation of the pressure plate, the wear powder that can be generated between the pressure plate pressing surface and the frictional connection of the clutch disk has a radius from the groove. The effect of discharging outward in the direction can be improved.

  According to an eighth aspect of the present invention, in the clutch cover assembly according to the first aspect, the pressure plate is formed in an annular shape. The groove portion has a curved groove portion formed in an arc shape or a concentric circle shape so as to extend in the circumferential direction between the inner peripheral end and the outer peripheral end of the pressing surface of the pressure plate. In this case, even if friction is generated between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk, the constraint on the thermal expansion of the pressure plate can be relaxed by the curved groove portion. Further, the frictional heat of the pressure plate can be radiated in the curved groove. At this time, if the curved groove is formed only at a position where the thermal expansion in the radial direction of the pressure plate is large and the curved groove is not formed at a position where the thermal expansion in the radial direction of the pressure plate is small, the pressure surface of the pressure plate It is possible to suppress a decrease in strength and rigidity of the pressure plate due to the formation of the curved groove. Further, wear powder that may be generated between the pressure plate pressing surface and the frictional connection of the clutch disk is retained in the curved groove when the clutch is engaged, and is curved when the clutch is released. It can be discharged to the outside from the groove. In this way, if the wear powder is allowed to stay in the curved groove portion so that the wear powder can be discharged from the curved groove portion, the wear powder is formed between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk. It becomes difficult to intervene, and the contact state between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk can be maintained stably.

  According to a ninth aspect of the present invention, in the clutch cover assembly of the first aspect, the pressure plate is formed in an annular shape. The groove portion is formed in a lattice shape at least at a part from the inner peripheral end to the outer peripheral end of the pressing surface of the pressure plate. In this case, even if friction occurs between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk, the restriction on the thermal expansion in the circumferential direction and the radial direction of the pressure plate can be relaxed by the groove portion. Further, the frictional heat of the pressure plate can be radiated in the groove portion. At this time, for example, if the pressure plate is formed so that the groove interval is close at a position where the thermal expansion is large, and the pressure plate is formed so that the groove portion is coarse at a position where the thermal expansion is small, the pressure plate It is possible to suppress a decrease in strength and rigidity of the pressure plate due to the formation of the groove on the pressing surface. Further, the abrasion powder that may be generated between the pressure plate pressing surface and the clutch disk frictional connection is retained in the groove when the clutch is engaged, and from the groove when the clutch is released. It can be discharged to the outside. Here, for example, if the groove formed in the pressure plate is formed to the outer peripheral end side, even if the clutch is not disengaged, the abrasion powder is removed from the groove in the radial direction by centrifugal force during rotation of the pressure plate. Can be discharged outward. As described above, if the wear powder is allowed to stay in the groove portion so that the wear powder can be discharged from the groove portion, the wear powder is interposed between the pressure plate pressing surface and the clutch disk friction coupling portion. This makes it difficult to maintain a stable contact state between the pressure plate pressing surface and the frictional connecting portion of the clutch disc.

  A clutch cover assembly according to a tenth aspect of the present invention is the clutch cover assembly according to any one of the first to ninth aspects, wherein a chamfered portion is formed at an end of the groove portion. In this case, by forming the chamfered portion at the end of the groove, stress concentration at the end of the groove due to the formation of the groove on the pressing surface of the pressure plate can be avoided.

  In the clutch cover assembly according to an eleventh aspect, in the clutch cover assembly according to any one of the first to tenth aspects, a chamfered portion is formed at a bottom portion of the groove portion. In this case, by forming the chamfered portion at the bottom of the groove portion, stress concentration due to the groove portion being formed on the pressing surface of the pressure plate can be avoided.

  In the clutch cover assembly according to a twelfth aspect, in the clutch cover assembly according to any one of the first to eleventh aspects, a chamfered portion is formed at a corner portion on the pressing surface side of the groove portion. In this case, by forming the chamfered portion at the pressing surface side corner portion of the groove portion, the end corner portion on the pressing surface side of the groove portion can be prevented from damaging the friction coupling portion of the clutch disk.

  In the clutch cover assembly according to a thirteenth aspect, in the clutch cover assembly according to any one of the first to twelfth aspects, the cross-sectional shape of the groove is changed according to the position of the groove extending in the radial direction. In this case, at the position where the thermal expansion of the pressure plate in the circumferential direction is large, the groove portion can effectively restrain the circumferential expansion of the pressure plate by increasing or decreasing the width or depth of the groove portion. Can be relaxed. In addition, at a position where the thermal expansion in the circumferential direction of the pressure plate is small, the strength and pressure of the pressure plate due to the formation of the groove on the pressing surface of the pressure plate can be reduced by reducing the width and depth of the groove. And the fall of rigidity can be suppressed.

  According to the present invention, the pressing surface of the pressure plate presses the friction coupling portion of the clutch disk in order to press the friction coupling portion of the clutch disk against the friction surface of the flywheel. At this time, since the groove portion is formed on the pressing surface of the pressure plate, even if friction occurs between the pressing surface of the pressure plate and the friction coupling portion of the clutch disk, the groove portion restricts the thermal expansion of the pressure plate. Can be relaxed. That is, the thermal deformation of the pressure plate can be suppressed by the groove formed on the pressing surface of the pressure plate. As described above, if the groove portion can suppress the thermal deformation of the pressure plate, the pressure plate is hardly plasticized, and the pressure plate is less likely to be deformed.

[First Embodiment]
[Configuration of clutch device and clutch cover assembly]
The clutch device 1 is mainly connected to an engine crankshaft (not shown) and a transmission main drive shaft (not shown), and is a device for transmitting and interrupting torque from the engine to the transmission. As shown in FIG. 1, the clutch device 1 mainly includes a flywheel 2, a clutch disk assembly 3, and a clutch cover assembly 4. The flywheel 2 is fixed to the tip of the crankshaft. The clutch disk assembly 3 has a clutch disk 31. The clutch disk 31 includes a friction coupling portion 32 that is disposed close to the friction surface 21 of the flywheel 2.

  The clutch cover assembly 4 according to the first embodiment of the present invention is a push-type clutch cover assembly 4 as shown in FIG. In the clutch cover assembly 4, the friction coupling portion 32 of the clutch disc 31 is pressed against the friction surface 21 of the flywheel 2 to couple the clutch, or the friction coupling portion 32 of the clutch disc 31 is brought into contact with the friction surface 21 of the flywheel 2. It is a device for releasing the pressed state and disconnecting the clutch. As shown in FIGS. 1 and 2, the clutch cover assembly 4 mainly includes a clutch cover 41, a pressure plate 42, and a diaphragm spring (pressing member) 43. The clutch cover 41 is a substantially dish-shaped plate member, and an outer peripheral portion thereof is fixed to the flywheel 2 by bolts, for example. A central hole 41a for allowing the main drive shaft to pass therethrough is formed at the center of the clutch cover 41.

  The pressure plate 42 is for pressing the friction coupling portion 32 of the clutch disc 31 against the friction surface 21 of the flywheel 2. The pressure plate 42 is an annular member as shown in FIGS. 1 and 3. The pressure plate 42 is formed with an annular protrusion 42b that protrudes outward from a surface opposite to the pressing surface 44 described later. Further, the pressure plate 42 is formed with a plurality of protruding portions 42c that protrude outward in the radial direction from the outer periphery at a predetermined interval in the outer peripheral direction. One end of the strap plate 6 is fixed to the plurality of protrusions 42 c by rivets 7. In this state, the other end side of the strap plate 6 extends in the outer peripheral tangential direction of the pressure plate 42, and the other end of the strap plate 6 is fixed to the clutch cover 41. In this way, the pressure plate 42 is attached to the clutch cover 41 via the strap plate 6 so as not to rotate relative to the clutch cover 41 and to be movable in the axial direction. At this time, the pressure plate 42 is biased in the axial direction away from the flywheel 2 by the strap plate 6.

  In the pressure plate 42, a surface facing the friction surface 21 of the flywheel 2 is a pressing surface 44 that can press the friction coupling portion 32 of the clutch disk 31. Between the pressing surface 44 of the pressure plate 42 and the friction surface 21 of the flywheel 2, the friction coupling portion 32 of the clutch disk 31 is disposed. A groove portion (an example of a first radial groove portion) 45 extending in the radial direction is formed on the pressing surface 44 of the pressure plate 42. The depth H of the groove 45 is set, for example, within a range of 2.5 mm to 20.0 mm. FIG. 4 shows the relationship between the residual deformation amount δ in the circumferential direction of the pressure plate and the depth H of the groove 45. FIG. 4 shows that the residual deformation amount δ of the pressure plate 42 decreases as the depth H of the groove 45 increases. In particular, when the depth H of the groove 45 is 2.5 mm or more, the residual deformation δ of the pressure plate 42 is reduced to almost half or less as compared with the case where the depth H of the groove 45 is 0.0 mm (no groove). doing. Accordingly, it can be seen that if the depth H of the groove 45 is set to 2.5 mm or more, the effect of forming the groove 45 on the pressing surface 44 of the pressure plate 42 can be sufficiently exhibited. The upper limit value 20.0 mm of the depth H of the groove 45 is set as a value that can sufficiently secure the strength and rigidity of the pressure plate.

  A plurality of the groove portions 45 are arranged at predetermined intervals in the circumferential direction between the inner peripheral end and the outer peripheral end of the pressing surface 44. Here, as shown in FIG. 3, the groove portions 45 are formed at four positions with a predetermined interval in the circumferential direction, and each groove portion 45 extends from a substantially central portion in the radial direction of the pressing surface 44 to the outer peripheral end. It is formed in a straight line. As described above, if the groove 45 is formed on the pressing surface 44 of the pressure plate 42, friction is generated in the circumferential direction between the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disk 31. In addition, the constraint on the thermal expansion of the pressure plate 42 in the circumferential direction can be evenly relaxed in the circumferential direction by the plurality of grooves 45. Moreover, the cross-sectional shape of each groove part 45 is uniformly formed in the rectangular shape from the inner end 45a of the groove part 45 to the outer end 45b. Further, the ratio (r / R) of the length R from the inner peripheral end to the outer peripheral end of the pressing surface 44 in the radial direction and the length r from the inner end 45 a to the outer end 45 b of the groove 45 is given to the pressing surface 44. Depending on the magnitude of the thermal expansion that occurs, it is variously set, for example, within a range of 0.05 to 0.98. At this time, the groove portion 45 is formed at a position where the thermal expansion in the circumferential direction of the pressure plate 42 increases, and the groove portion 45 is not formed at a position where the thermal expansion in the circumferential direction of the pressure plate 42 is relatively small. By doing so, it is possible to suppress a decrease in strength and rigidity of the pressure plate 42 due to the formation of the groove 45 in the pressing surface 44 of the pressure plate 42.

  At both end portions (inner end 45a and outer end 45b) of the groove portion 45, the bottom corner portion 45c and both side corner portions 45d of the groove portion 45 are formed in an arc shape. At this time, the arc radius of the bottom corner 45c of the groove 45 is set within a range of 1 mm or more and 20 mm or less, for example. And the arc radius of the both-sides corner part 45d of the groove part 45 is set within the range of 1 mm or more and 40 mm or less, for example. Thus, if the bottom corner 45c and both side corners 45d of the groove 45 are formed in an arc shape at both ends 45a and 45b of the groove 45, the bottom corner 45c and both sides of the groove 45 are formed. Stress concentration that may occur in the corner portion 45d can be avoided.

  Between the both end portions 45a and 45b of the groove portion 45, the pressing surface side corner portion 45e of the groove portion 45 is formed in an arc shape. At this time, the arc radius of the pressing surface side corner portion 45e of the groove 45 is set within a range of, for example, 1 mm or more and 20 mm or less. As described above, when the pressing surface side corner 45e of the groove 45 is formed in an arc shape between the both ends 45a and 45b of the groove 45, the pressing surface 44 of the pressure plate 42 is connected to the friction coupling portion 32 of the clutch disk 31. It is possible to prevent the pressing surface side corner portion 45e of the groove portion 45 from damaging the friction coupling portion 32 of the clutch disc 31 when being brought into contact with. In addition, the bottom 45f of the groove 45 is formed in an arc shape between both end portions 45a and 45b of the groove 45. At this time, the arc radius of the bottom 45f of the groove 45 is set within a range of 1 mm to 20 mm, for example. Thus, if the bottom 45f of the groove 45 is formed in an arc shape between the both ends 45a, 45b of the groove 45, stress concentration due to the groove formed on the pressing surface of the pressure plate can be avoided.

  The diaphragm spring 43 is for pressing the pressure plate 42 against the friction surface 21 side of the flywheel 2. The diaphragm spring 43 is disposed between the pressure plate 42 and the bottom of the clutch cover 41 as shown in FIG. As shown in FIGS. 1 and 2, the diaphragm spring 43 is a disk-shaped member, and includes an annular elastic portion 43a and a plurality of lever portions 43b extending radially inward from the inner peripheral end of the annular elastic portion 43a. It consists of and. The outer peripheral portion of the annular elastic portion 43 a is in contact with the annular protrusion 42 b of the pressure plate 42. An inner peripheral portion of the annular elastic portion 43 a is supported on the clutch cover 41 by a claw portion 41 b formed on the clutch cover 41. In this state, the annular elastic portion 43a biases the pressure plate 42 toward the flywheel 2 side. Here, when the tip portions of the plurality of lever portions 43b are pressed toward the flywheel 2 by a clutch operating mechanism (not shown), the pressure plate 42 is urged toward the flywheel 2 by the annular elastic portion 43a. The state is released, and the pressure plate 42 is urged by the strap plate 6 in a direction away from the flywheel 2.

[Operation of clutch cover assembly]
The operation of the clutch cover assembly 4 when torque from the engine is input to the clutch cover assembly 4 via the flywheel 2 will be described.

  Torque from the engine is input to the clutch cover assembly 4 via the flywheel 2 fixed to the tip of the crankshaft by the rotational force of the crankshaft of the engine. Then, the clutch cover 41 fixed to the flywheel 2 rotates together with the flywheel 2. At the same time, a diaphragm spring 43 supported on the clutch cover 41 via the claw portion 41 b and a pressure plate 42 attached to the clutch cover 41 via the strap plate 6 so as not to be relatively rotatable and axially movable together with the clutch cover 41. Rotate. In this state, when the pressure plate 42 is urged toward the flywheel 2 by the annular elastic portion 43 a of the diaphragm spring 43, the pressing surface 44 of the pressure plate 42 abuts on the friction coupling portion 32 of the clutch disc 31 and the clutch disc The friction connecting portion 32 of 31 is pressed against the friction surface 21 of the flywheel 2. Then, the rotational force of the clutch cover assembly 4 is transmitted to the clutch disk assembly 3 via the frictional connection portion 32 of the clutch disk 31. On the other hand, when the pressure plate 42 is biased in a direction away from the flywheel 2 side via the plurality of lever portions 43b of the diaphragm spring 43 and the strap plate 6 by a clutch operating mechanism (not shown), the pressure plate 42 The state where the pressing surface 44 presses the friction coupling portion 32 of the clutch disc 31 against the friction surface 21 of the flywheel 2 is released. Then, the rotational force transmitted from the clutch cover assembly 4 to the clutch disk assembly 3 via the frictional connection portion 32 of the clutch disk 31 is not transmitted. In this way, the pressing surface 44 of the pressure plate 42 presses the friction coupling portion 32 of the clutch disc 31 against the friction surface 21 of the flywheel 2, or the friction coupling portion 32 of the clutch disc 31 against the friction surface 21 of the flywheel 2. By releasing the pressed state, the clutch cover assembly 4 can transmit or shut off the torque from the engine to the clutch disk assembly 3.

  In the conventional clutch cover assembly 4, when the pressing surface 44 of the pressure plate 42 abuts on the friction coupling portion 32 of the clutch disk 31, the pressure plate 42 is interposed between the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disk 31. Since very large friction occurs in the circumferential direction, the pressure plate 42 is easily expanded due to frictional heat and thermally deformed. Further, when the pressing surface 44 of the pressure plate 42 presses the friction coupling portion 32 of the clutch disk 31, there is a transient fluctuation between the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disk 31. Even if it acts, a very large friction is generated in the circumferential direction between the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disk 31, and the pressure plate 42 expands due to frictional heat and heats up. It was easy to deform. When the pressure plate 42 is thermally deformed, the contact state between the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disk 31 becomes uneven, and the pressure plate 42 and the clutch disk 31 slip. There was a fear. In particular, when excessive frictional heat acts on the pressure plate, the pressure plate 42 partially yields and plasticizes, and even if the frictional heat of the pressure plate cools down, the pressure plate 42 becomes plasticized. Will leave residual deformation. Then, regardless of whether the pressure plate 42 is thermally deformed by frictional heat, the contact state between the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disk 31 becomes unstable, and the pressure plate 42 and the clutch disk 31 may slip.

  In the clutch cover assembly 4 of the first embodiment, on the pressing surface 44 of the pressure plate 42, the groove portions 45 are formed at four locations at predetermined intervals in the circumferential direction, and each groove portion 45 is formed on the pressing surface 44. Are formed in a straight line from the substantially central portion in the radial direction to the outer peripheral end. As a result, even if friction occurs in the circumferential direction between the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disc 31, the restraint against the thermal expansion in the circumferential direction of the pressure plate 42 is restricted in the radial direction. It can be relaxed by the extended groove 45. Further, the frictional heat of the pressure plate 42 can be radiated in the groove 45. From these things, the thermal deformation of the pressure plate 42 can be suppressed by the groove 45 formed on the pressing surface 44 of the pressure plate 42. As described above, if the groove portion 45 can relax the constraint on the thermal expansion of the pressure plate 42, the pressure plate 42 becomes difficult to plasticize, and the pressure plate 42 is also less likely to be deformed. For this reason, the slip between the pressure plate 42 and the clutch disk 31 can be suppressed. Further, by allowing the outer end 45 b of the groove 45 to penetrate to the outer peripheral end of the pressing surface 44, the centrifugal force generated when the pressure plate 42 rotates causes the pressing surface 44 of the pressure plate 42 and the friction coupling portion 32 of the clutch disk 31 to move. It is also possible to expect an effect of discharging wear powder that may be generated between the grooves 45 outward in the radial direction.

[Second Embodiment]
[Outline of clutch device and configuration of clutch cover assembly]
The clutch device 101 is mainly connected to an engine crankshaft (not shown) and a transmission main drive shaft (not shown), and is a device for transmitting and interrupting torque from the engine to the transmission. As shown in FIG. 5, the clutch device 101 mainly includes a flywheel 102, a clutch disk assembly 103, and a clutch cover assembly 104. The flywheel 102 is fixed to the tip of the crankshaft. The clutch disk assembly 103 has a clutch disk 131. The clutch disk 131 includes a friction coupling portion 132 disposed close to the friction surface 121 of the flywheel 102.

  The clutch cover assembly 104 according to the second embodiment of the present invention is a push type clutch cover assembly 104 as shown in FIG. The clutch cover assembly 104 is a device for pressing the friction connecting portion 132 of the clutch disk 131 against the flywheel 102 to connect the clutch, or releasing the pressing to disconnect the clutch. As shown in FIG. 5, the clutch cover assembly 104 mainly includes a clutch cover 141, a pressure plate 142, and a diaphragm spring (pressing member) 143. In the second embodiment, since the configuration excluding the groove portion 145 of the pressure plate 142 is the same as the configuration of the first embodiment, the description of the configuration of the same portion is omitted, and only the description of the groove portion 145 of the pressure plate 142 is given. Shall.

  As shown in FIG. 6, the pressure plate 142 has a pressing surface 144 capable of pressing the friction coupling portion 132 of the clutch disk 131 on the surface facing the friction surface 121 of the flywheel 102. Between the pressing surface 144 of the pressure plate 142 and the friction surface 121 of the flywheel 102, a friction coupling portion 132 of the clutch disk 131 is disposed. A groove portion (an example of a second radial groove portion) 145 extending in the radial direction is formed on the pressing surface 144 of the pressure plate 142. The depth H of the groove 145 is set within a range of, for example, 2.5 mm or more and 20.0 mm or less. From the results shown in FIG. 4, if the depth H of the groove 145 is set to 2.5 mm or more, the effect obtained by forming the groove 145 on the pressing surface 144 of the pressure plate 42 can be sufficiently exhibited. .

  A plurality of the groove portions 145 are arranged at predetermined intervals in the circumferential direction between the inner peripheral end and the outer peripheral end of the pressing surface 144. Here, as shown in FIG. 6, the groove portions 145 are formed at four positions with a predetermined interval in the circumferential direction, and each groove portion 145 is formed to linearly penetrate in the radial direction on the pressing surface 144. Has been. The groove portion 145 is inclined at a predetermined angle θ1 with respect to the radial direction so that the outer end 145b of the groove portion 145 is located in a direction opposite to the rotation direction θ of the pressure plate 142 with the inner end 145a of the groove portion 145 as a base end. It is formed in a straight line. The angle θ1 of the groove 145 is set, for example, within a range of 1 degree to 45 degrees with respect to the radial direction. Moreover, the cross-sectional shape of each groove part 45 is uniformly formed in the rectangular shape from the inner end 45a of the groove part 45 to the outer end 45b. Since such groove portions 145 may be formed so as to penetrate linearly in the radial direction on the pressing surface 144, each groove portion 145 can be easily formed on the pressing surface 144 of the pressure plate 142.

  At both ends (the inner end 145a and the outer end 145b) of the groove portion 145, the bottom corner portion 145c and both side corner portions 145d of the groove portion 145 are formed in an arc shape. At this time, the arc radius of the bottom corner portion 145c of the groove portion 145 is set within a range of 1 mm or more and 20 mm or less, for example. And the arc radius of the both-sides corner part 145d of the groove part 145 is set within the range of 1 mm or more and 40 mm or less, for example. In this way, when the bottom corner 145c and both side corners 145d of the groove 145 are formed in an arc shape at both ends 145a and 145b of the groove 145, the bottom corner 145c and both sides of the groove 145 are formed. Stress concentration that can occur in the corner portion 145d can be avoided. In addition, a pressing surface side corner portion 145e of the groove portion 145 is formed in an arc shape between both end portions 145a and 145b of the groove portion 145. At this time, the arc radius of the pressing surface side corner portion 145e of the groove portion 145 is set within a range of, for example, 1 mm or more and 20 mm or less. Thus, if the pressing surface side corner portion 145e of the groove portion 145 is formed in an arc shape between the both end portions 145a and 145b of the groove portion 145, the pressing surface 144 of the pressure plate 142 becomes the friction coupling portion 132 of the clutch disk 131. It is possible to prevent the pressing surface side corner portion 145e of the groove portion 145 from damaging the frictional coupling portion 132 of the clutch disk 131 when it is brought into contact with. Further, a bottom portion 145f of the groove portion 145 is formed in an arc shape between both end portions 145a and 145b of the groove portion 145. At this time, the arc radius of the bottom portion 145f of the groove portion 145 is set within a range of, for example, 1 mm or more and 20 mm or less. Thus, if the bottom portion 145f of the groove portion 145 is formed in an arc shape between both end portions 145a and 145b of the groove portion 145, stress concentration due to the groove portion being formed on the pressing surface of the pressure plate can be avoided.

  In the clutch cover assembly 104 of the second embodiment, the outer end 145b of the groove 145 is opposite to the rotation direction θ of the pressure plate 142 with the inner end 145a of the groove 145 as the base end on the pressing surface 144 of the pressure plate 142. The groove portion 145 is formed in a straight line so as to be inclined at a predetermined angle θ1 with respect to the radial direction so as to be positioned in the direction. As described above, if the groove portion 145 is formed on the pressing surface 144 of the pressure plate 142, it is assumed that friction has occurred in the circumferential direction between the pressing surface 144 of the pressure plate 142 and the friction coupling portion 132 of the clutch disk 131. In addition, the groove portion 145 is not restricted by the inner peripheral end and the outer peripheral end, and the restriction on the thermal expansion of the pressure plate 142 in the circumferential direction can be evenly relaxed in the circumferential direction by the plurality of groove portions 145. That is, thermal deformation of the pressure plate 142 can be suppressed by the groove portion 145 formed on the pressing surface 144 of the pressure plate 142. As described above, if the groove portion 145 can suppress the thermal deformation of the pressure plate 142, the pressure plate 142 is less likely to be plasticized, and the pressure plate 142 is also less likely to undergo residual deformation. Further, since the groove portion 145 is penetrated from the inner peripheral end to the outer peripheral end, an air flow radially outward is formed in the groove portion 145 due to the centrifugal force when the pressure plate 142 rotates, and the friction of the pressure plate 142 Heat can be effectively radiated from the groove 145. That is, the heat dissipation effect in the groove 145 of the pressure plate 142 can be improved, and thermal deformation can be effectively suppressed. When a flow of air outward in the radial direction is formed in the groove portion 145, wear powder that may be generated between the pressing surface 144 of the pressure plate 142 and the frictional connection portion 132 of the clutch disk 131 is generated from the groove portion 145 in the radial direction. It can be effectively discharged outward.

[Other Embodiments]
(A) In the first and second embodiments, the example in which the groove portions 45 and 145 are linearly formed in the radial direction on the pressing surfaces 44 and 144 has been shown. However, the method for forming the groove portions 45 and 145 is described above. The present invention is not limited to the first and second embodiments, and the grooves 45 and 145 may be formed in the radial direction of the pressing surfaces 44 and 144 by giving the grooves 45 and 145 curvature. For example, as shown in FIG. 7, on the pressing surface 244 of the pressure plate 242, the outer end 245b of the groove 245 is positioned in a direction opposite to the rotational direction θ of the pressure plate 242 with the inner end 245a of the groove 245 as a base end. The groove 245 may be formed in the radial direction of the pressing surface 244 by giving the groove 245 a curvature. In this case, the same effects as those of the first and second embodiments can be obtained, and an air flow radially outward in the groove portion 245 according to the rotation of the pressure plate 242 causes the second embodiment. Therefore, it can be generated between the effect of dissipating the frictional heat of the pressure plate 242 from the groove 245 when the pressure plate 242 is rotated, and the pressing surface 244 of the pressure plate 242 and the friction coupling portion of the clutch disk. The effect of discharging the wear powder from the groove portion 245 in the radial direction can be further improved.

  (B) In the first embodiment, an example in which each groove portion 45 is linearly formed from a substantially central portion in the radial direction of the pressing surface 44 to the outer peripheral end is shown. However, as in the second embodiment. The groove portion 45 is inclined at a predetermined angle with respect to the radial direction so that the outer end 45b of the groove portion 45 is located in the direction opposite to the rotation direction of the pressure plate 42 with the inner end 45a of the groove portion 45 as a base end. You may form in. In this case, the effects shown in the first embodiment can be obtained, and the centrifugal force generated when the pressure plate 42 rotates causes the pressure plate 44 between the pressure plate 42 and the friction coupling portion 32 of the clutch disc 31. The wear powder that can be discharged can be effectively discharged radially outward from the groove 45.

  (C) In the second embodiment, an example in which the groove portion 145 is formed in a straight line by being inclined at a predetermined angle θ1 with respect to the radial direction has been shown. However, as in the first embodiment, the groove portion 145 is The pressing surface 144 may be linearly formed in the radial direction (θ1 = 0 degree). In this case, when the pressure plate 142 rotates, the frictional heat of the pressure plate 142 is radiated from the groove portion 145, and wear powder that may be generated between the pressing surface 144 of the pressure plate 142 and the friction coupling portion 132 of the clutch disk 131 is removed from the groove portion 145. Although the effect of discharging outward in the radial direction slightly decreases, the effect shown in the second embodiment can be sufficiently ensured.

  (D) In the first and second embodiments, an example in which the cross-sectional shape of the groove portions 45 and 145 extending in the radial direction is formed in a certain rectangular shape has been shown, but the cross-sectional shape of the groove portions 45 and 145 is It is not limited to the said embodiment, You may change according to the position of the groove parts 45 and 145 extended in a radial direction. For example, as shown in FIG. 8, at a position where the thermal expansion of the pressure plate 342 in the circumferential direction can be increased, if the depth H of the groove 345 is increased (H = H1), the pressure plate 342 is increased. The restriction on the thermal expansion in the circumferential direction can be effectively relaxed by the groove portion 345. Further, at a position where the thermal expansion of the pressure plate 342 is difficult to increase in the circumferential direction, if the depth H of the groove 345 is made shallow (H = H2), the groove 345 is formed on the pressing surface 344 of the pressure plate 342. It is possible to suppress a decrease in strength and rigidity of the pressure plate 342 due to the formation of. Here, the restraint on the thermal expansion in the circumferential direction of the pressure plate 342 is eased by adjusting the depth H of the groove 345, but it can also be eased by adjusting the width of the groove 345. is there.

  (F) In the first and second embodiments and other embodiments, the groove portions 45, 145, 245 are formed at four locations at intervals in the circumferential direction on the pressing surfaces 44, 144, 244. Although an example was shown, the number of locations of the groove portions 45, 145, 245 is not limited to the above-described embodiment, and may be any way. For example, the grooves 45, 145, and 245 may be formed on the pressing surfaces 44, 144, and 244 with the number of places less than 4 or 5 or more (see FIG. 9).

  (G) In the first and second embodiments and other embodiments, an example in which the groove portions 45, 145, 245 are formed at equal intervals in the circumferential direction on the pressing surfaces 44, 144, 244 has been shown. However, the intervals in the circumferential direction of the groove portions 45, 145, and 245 are not necessarily formed at equal intervals. For example, as shown in FIG. 9, the groove portions 345 may be formed at unequal intervals in the circumferential direction on the pressing surface 344. Thus, even if the groove 345 is formed on the pressing surface 344, the same effect as in the above embodiment can be obtained.

  (H) In the first and second embodiments and other embodiments, the grooves 45, 145, 245, 345 are formed so as to extend in the radial direction of the pressing surfaces 44, 144, 244, 344. For example, as shown in FIG. 10, for example, not only the grooves 45, 145, 245, and 345 (445a in FIG. 10) shown in the first and second embodiments and other embodiments, but also the circumference A groove portion 445 b (an example of a curved groove portion) extending in the direction may also be formed on the pressing surface 444. Thus, even if the groove portions 445a and 445b are formed on the pressing surface 444, the same effect as in the above embodiment can be obtained. Further, in this case, even if friction is generated between the pressing surface 444 of the pressure plate 442 and the friction coupling portion (not shown) of the clutch disk, the groove portion 445b restricts the thermal expansion of the pressure plate 442 in the radial direction. Can be relaxed.

  (I) In the first and second embodiments and other embodiments, the groove portions 45, 145, 245, 345, 445a, 445b are arranged in the radial direction or circumferential direction of the pressing surfaces 44, 144, 244, 344, 444. However, the grooves 545 may be formed in a lattice shape on the pressing surface 544 as shown in FIG. 11, for example. Thus, even if the groove portion 545 is formed on the pressing surface 544, the same effect as in the above embodiment can be obtained. Further, in this case, even if friction is generated between the pressing surface 544 of the pressure plate 542 and the friction coupling portion of the clutch disc, the restriction on the thermal expansion in the radial direction of the pressure plate 542 can be relaxed by the groove portion. .

  (J) In the said 1st Embodiment, although the groove part 45 showed the example in the case of being linearly formed from the approximate center part of the radial direction of the press surface 44 to the outer periphery end, as shown, for example in FIG. Not only the groove 45 (645a in FIG. 12) shown in the first embodiment but also the groove 145 (645b in FIG. 12) shown in the second embodiment may be formed on the pressing surface 644. Thus, even if the groove portions 645a and 645b are formed on the pressing surface 644, the same effect as in the above embodiment can be obtained. The groove portion 645b corresponding to the second embodiment is linearly formed with a predetermined angle with respect to the radial direction. However, the groove portion 645b is formed linearly in the radial direction on the pressing surface 144. May be.

  (K) In the second embodiment and the other embodiments, an example in which the groove portions 145, 245, and 645 are formed at a predetermined angle in the direction opposite to the rotation direction θ with respect to the radial direction is shown. The direction in which the groove portions 145, 245, and 645 are inclined is not limited to the above embodiment, and the groove portions 145, 245, and 645 may be inclined in the same direction as the rotation direction θ with respect to the radial direction. Also in other embodiment (b), the groove 45 is inclined in the direction opposite to the rotational direction θ with respect to the radial direction, but the groove 45 is inclined in the same direction as the rotational direction θ with respect to the radial direction. You may do it. Even if it does in this way, the effect similar to the said embodiment can be anticipated.

The longitudinal cross-sectional schematic of the clutch apparatus and clutch cover assembly as 1st this embodiment (II-II cross section shown in FIG. 2). The partial top view which removed a part of clutch cover assembly. FIG. 2 is a plan view of a pressure plate of the clutch cover assembly (viewed from the II side shown in FIG. 1) and an enlarged view of a groove. The figure which showed the relationship between the residual deformation amount of a pressure plate, and the depth of a groove part. The longitudinal cross-sectional schematic of the clutch apparatus and clutch cover assembly as 2nd Embodiment. The figure in the second embodiment corresponding to FIG. 3 of the first embodiment (viewed from the III-III side shown in FIG. 5). The figure equivalent to FIG. 6 of the said 1st and 2nd embodiment in other embodiment. The figure showing the cross-sectional shape which changes according to the position of the groove part in other embodiment. The figure equivalent to FIG. 6 of the said 1st and 2nd embodiment in other embodiment. The figure equivalent to FIG. 6 of the said 1st and 2nd embodiment in other embodiment. The figure equivalent to FIG. 6 of the said 1st and 2nd embodiment in other embodiment. The figure equivalent to FIG. 6 of the said 1st and 2nd embodiment in other embodiment.

Explanation of symbols

2,102 Flywheel 4,104 Clutch cover assembly 31,131 Clutch disk 32,132 Friction connecting portion 21,121 Friction surface 41,141 Clutch cover 42,142,242,342 Pressure plate 43,143 Diaphragm spring (pressing member) )
44, 144, 244, 344, 444, 544, 644 Press surface 45, 145, 245, 345, 445a, 445b, 545, 645a, 645b Groove 45a, 145a, 245a Groove inner end 45b, 145b, 245b Outside groove End H Groove depth δ Residual deformation

Claims (13)

A clutch cover assembly for engaging the clutch by pressing the friction coupling portion of the clutch disk against the friction surface of the flywheel,
A clutch cover fixed to the flywheel on the friction surface side of the flywheel;
A pressure plate that is mounted on the clutch cover so as not to rotate relative to the clutch cover, and that presses the friction coupling portion of the clutch disc against the friction surface of the flywheel;
A pressing member supported by the clutch cover, for pressing the pressure plate toward the friction surface of the flywheel;
With
A pressure surface that presses the friction coupling portion is provided on one surface of the pressure plate, and a groove portion is formed on the pressure surface.
Clutch cover assembly. The pressure plate is formed in an annular shape,
The groove portion is formed so as to extend in a radial direction at least at a part from an inner peripheral end to an outer peripheral end of the pressing surface, and a plurality of the groove portions are arranged at intervals in the circumferential direction. Clutch cover assembly.   3. The clutch cover assembly according to claim 2, wherein the groove portion includes a first radial groove portion formed between an inner peripheral end and an outer peripheral end to an outer peripheral end on the pressing surface.   4. The clutch cover assembly according to claim 2, wherein the groove has a second radial groove formed on the pressing surface from an inner peripheral end to an outer peripheral end. 5.   The clutch cover assembly according to any one of claims 2 to 4, wherein the groove portion extends linearly in the radial direction.   The clutch cover assembly according to any one of claims 2 to 4, wherein the groove portion extends linearly at a predetermined angle with respect to the radial direction.   The clutch cover assembly according to any one of claims 2 to 4, wherein the groove portion extends in the radial direction with a curvature. The pressure plate is formed in an annular shape,
The said groove part has the curved groove part formed in the circular arc shape or the concentric form so that it might extend in the circumferential direction between the inner peripheral end of the said press surface, and an outer peripheral end. A clutch cover assembly according to claim 1. The pressure plate is formed in an annular shape,
2. The clutch cover assembly according to claim 1, wherein the groove is formed in a lattice shape at least at a part between an inner peripheral end and an outer peripheral end of the pressing surface.   The clutch cover assembly according to any one of claims 1 to 9, wherein a chamfered portion is formed at an end of the groove portion.   The clutch cover assembly according to any one of claims 1 to 10, wherein a chamfered portion is formed at a bottom portion of the groove portion.   The clutch cover assembly according to any one of claims 1 to 11, wherein a chamfered portion is formed at a corner portion on the pressing surface side of the groove portion. The clutch cover assembly according to any one of claims 1 to 12, wherein a cross-sectional shape of the groove portion changes according to a position of the groove portion extending in the radial direction.

Images