Clutch device

Abstract

To effectively reduce pressing force generated due to the action of an assist cam surface.SOLUTION: A clutch device 10 includes: a clutch center 40; a pressure plate 70 provided to be capable of approaching / separating to / from the clutch center 40 and being relatively rotatable; and a disc spring 120 held by the clutch center 40. The disc spring 120 is disposed so as to come into contact with an output side rotary plate 22 held by the clutch center 40, arranged between the output side rotary plate 22 adjacent in a direction D in which the plate is held by the clutch center 40, and positioned closer to a second direction D2 than a center CL in the direction D from a first output side rotary plate 22A positioned most close to a first direction D1 among the plurality of output side rotary plates 22 held by the clutch center 40 to a second output side rotary plate 22B positioned most close to the second direction D2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a clutch device. [Background technology]

[0002] Saddle-type vehicles such as motorcycles are equipped with a clutch device that can transmit and cut off the rotational driving force of a power source such as an engine to a driving wheel.For example, Patent Document 1 discloses a power transmission device (hereinafter referred to as a clutch device) that has an input member (hereinafter referred to as an input shaft) connected to the engine side, an output member (hereinafter referred to as an output shaft) connected to the driving wheel side, a clutch member (hereinafter referred to as a clutch center) connected to the output shaft, and a pressure member (hereinafter referred to as a pressure plate) that can move toward or away from the clutch center.

[0003] Moreover, the clutch center and pressure plate of Patent Document 1 each have an assist cam surface that generates a force in a direction that moves the pressure plate closer to the clutch center when the rotational driving force of the engine is in a state where it can be transmitted to the output shaft, thereby increasing the pressing force (pressing force) between the input side rotating plate and the output side rotating plate. Furthermore, the clutch device of Patent Document 1 has a disc spring that attenuates the pressing force in order to suppress a sudden increase in the assist torque due to the pressing force. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-137039 A Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the disc spring is held at the clutch center and disposed at the position farthest from the pressure plate in the direction of movement of the pressure plate. Therefore, in a clutch device set with a relatively large pressing force or a clutch device with a relatively large number of output side rotating plates and input side rotating plates, a problem may occur in that the pressing force cannot be effectively attenuated.

[0006] The present invention has been made in consideration of these points, and its purpose is to provide a clutch device that can suppress a sudden increase in assist torque by effectively attenuating the pressing force generated by the action of the assist cam surface. [Means for solving the problem]

[0007] The clutch device according to the present invention is a clutch device for transmitting or interrupting the rotational driving force of an input shaft to an output shaft, and includes a clutch center that is accommodated in a clutch housing that holds a plurality of input side rotating plates that are rotationally driven by the rotational drive of the input shaft, holds a plurality of output side rotating plates arranged alternately with the input side rotating plates, and is rotationally driven together with the output shaft, a pressure plate that is provided so as to be able to approach or move away from the clutch center and to be rotatable relative to the clutch center, and is able to press the input side rotating plates and the output side rotating plates, and a disc spring held by the clutch center, wherein the clutch center includes a center side cam portion having a center side assist cam surface that generates a force in a direction that causes the pressure plate to approach the clutch center in order to increase the pressing force between the input side rotating plate and the output side rotating plate when the clutch center rotates relative to the pressure plate, and the pressure plate is configured to rotate in a direction that causes the pressure plate to approach the clutch center in order to increase the pressing force between the input side rotating plate and the output side rotating .... the pressure plate is provided with a pressure side cam portion having a pressure side assist cam surface that generates a force in a direction that brings the pressure plate closer to the clutch center in order to increase the pressing force between the input side rotating plate and the output side rotating plate when the pressure plate rotates relative to the clutch center, and when the direction in which the pressure plate moves is defined as the moving direction, the direction in which the pressure plate approaches the clutch center is defined as a first direction, and the direction in which the pressure plate moves away from the clutch center is defined as a second direction, the disc spring is provided so as to be able to come into contact with the output side rotating plate held by the clutch center, is disposed between the output side rotating plates held by the clutch center that are adjacent to each other in the moving direction, and is positioned in the second direction relative to the center of the moving direction from a first output side rotating plate that is furthest in the first direction to a second output side rotating plate that is furthest in the second direction among the multiple output side rotating plates held by the clutch center.

[0008] According to the clutch device of the present invention, the disc spring held by the clutch center is provided so as to be able to come into contact with the output side rotating plate held by the clutch center, is disposed between the output side rotating plates adjacent in the moving direction held by the clutch center, and is located in the second direction from the center of the moving direction from the first output side rotating plate to the second output side rotating plate. According to the above aspect, the disc spring is disposed in a position closer to the pressure plate that generates the pressing force, so that the pressing force can be effectively attenuated. This makes it possible to suppress a sudden increase in the assist torque, and suppress the sudden engagement of the clutch and the occurrence of vibration.

[0009] Another clutch device according to the present invention is a clutch device for transmitting or interrupting the rotational driving force of an input shaft to an output shaft, comprising: a clutch center accommodated in a clutch housing holding a plurality of input side rotating plates which are rotationally driven by the rotational driving of the input shaft and which is rotationally driven together with the output shaft; a pressure plate which is provided so as to be able to approach or move away from the clutch center and to be rotatable relative to the clutch center, holds at least some of a plurality of output side rotating plates which are arranged alternately with the input side rotating plates, and is capable of pressing the input side rotating plates and the output side rotating plates; and a disc spring held by the pressure plate, and when the clutch center rotates relative to the pressure plate, the input side rotating plates and the output side rotating plates are pressed against each other by the pressure plate. the pressure plate is provided with a center side cam portion having a center side assist cam surface that generates a force in a direction that brings the pressure plate closer to the clutch center in order to increase the pressing force between the input side rotating plate and the output side rotating plate when the pressure plate rotates relative to the clutch center, and the pressure plate is provided with a pressure side cam portion having a pressure side assist cam surface that generates a force in a direction that brings the pressure plate closer to the clutch center in order to increase the pressing force between the input side rotating plate and the output side rotating plate, and when the direction in which the pressure plate moves is defined as the moving direction, the disc spring is aligned in the moving direction with the output side rotating plate held by the pressure plate and is arranged to be able to come into contact with the output side rotating plate held by the pressure plate.

[0010] According to the clutch device of the present invention, the disc spring held by the pressure plate is aligned with the output side rotating plate held by the pressure plate in the moving direction and is arranged to be able to come into contact with the output side rotating plate held by the pressure plate. According to the above aspect, since the disc spring is arranged on the pressure plate which generates the pressing force, the pressing force can be effectively attenuated. This makes it possible to suppress a sudden increase in the assist torque, and to suppress the sudden engagement of the clutch and the occurrence of vibration. Effect of the Invention

[0011] According to the present invention, it is possible to provide a clutch device capable of suppressing a sudden increase in assist torque by effectively attenuating the pressing force generated by the action of the assist cam surface. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view of a clutch device according to one embodiment. [Diagram 2] FIG. 2 is a perspective view of the clutch center according to one embodiment. [Diagram 3] FIG. 3 is a plan view of the clutch center according to one embodiment. [Figure 4] FIG. 4 is a perspective view of a pressure plate according to one embodiment. [Diagram 5] FIG. 5 is a plan view of a pressure plate according to one embodiment. [Figure 6] FIG. 6 is a perspective view of a pressure plate according to one embodiment. [Figure 7] FIG. 7 is a plan view of a pressure plate according to one embodiment. [Figure 8A] FIG. 8A is a schematic diagram for explaining the action of the center side assist cam surface and the pressure side assist cam surface. [Figure 8B] FIG. 8B is a schematic diagram for explaining the action of the center-side slipper cam surface and the pressure-side slipper cam surface. [Figure 9]FIG. 9 is a cross-sectional view of a clutch device according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of a clutch device according to the present invention will be described with reference to the drawings. Note that the embodiment described here is not intended to limit the present invention in any particular way. In addition, the same reference numerals are used for members and parts that perform the same functions, and duplicated descriptions will be omitted or simplified as appropriate.

[0014] First Embodiment 1 is a cross-sectional view of a clutch device 10 according to this embodiment. The clutch device 10 is provided on a saddle-type vehicle such as a motorcycle. The clutch device 10 is a device that transmits or cuts off the rotational driving force of an input shaft (crankshaft) of an engine, which is a power source of the motorcycle, to an output shaft 15. The clutch device 10 is a device that transmits or cuts off the rotational driving force of the input shaft to a driving wheel (rear wheel) via the output shaft 15. The clutch device 10 is disposed between the engine and the transmission.

[0015] In the following description, the direction in which the pressure plate 70 of the clutch device 10 approaches and moves away from the clutch center 40 (i.e., the direction in which the pressure plate 70 moves) is referred to as direction D, the direction in which the pressure plate 70 approaches the clutch center 40 is referred to as a first direction D1, and the direction in which the pressure plate 70 moves away from the clutch center 40 is referred to as a second direction D2. Direction D is an example of a moving direction. The circumferential direction (i.e., the rotation direction) of the clutch center 40 and the pressure plate 70 is defined as the circumferential direction S, the direction from one center side cam portion 60 to the other center side cam portion 60 (the direction from one pressure side cam portion 90 to the other pressure side cam portion 90) in relation to the circumferential direction S is defined as the first circumferential direction S1 (see FIG. 2), and the direction from the other center side cam portion 60 to one center side cam portion 60 (the direction from the other pressure side cam portion 90 to one pressure side cam portion 90) is defined as the second circumferential direction S2 (see FIG. 2). In this embodiment, the axial direction of the output shaft 15 is the same as the direction D. The pressure plate 70 and the clutch center 40 rotate in the first circumferential direction S1 (i.e., the direction from the center side assist cam surface 60A of one center side cam portion 60 to the center side slipper cam surface 60S). However, the above directions are merely defined for the convenience of explanation, and do not limit the installation mode of the clutch device 10 or the present invention in any way.

[0016] As shown in FIG. 1, the clutch device 10 includes an output shaft 15, a plurality of input side rotating plates 20, a plurality of output side rotating plates 22, a clutch housing 30, a clutch center 40, a pressure plate 70, a stopper plate 100, and a disc spring 120.

[0017] As shown in Fig. 1, the output shaft 15 is a shaft body formed into a hollow shape. One end of the output shaft 15 rotatably supports an input gear 35 and a clutch housing 30 (described later) via a needle bearing 15A. The output shaft 15 fixedly supports a clutch center 40 via a nut 15B. That is, the output shaft 15 rotates integrally with the clutch center 40. The other end of the output shaft 15 is connected to, for example, a transmission (not shown) of a motorcycle.

[0018] As shown in FIG. 1, the output shaft 15 includes a push rod 16A in its hollow portion 15H and a push member 16B provided adjacent to the push rod 16A. The hollow portion 15H functions as a flow passage for clutch oil. The clutch oil flows inside the output shaft 15, i.e., inside the hollow portion 15H. The push rod 16A and the push member 16B are provided slidably inside the hollow portion 15H of the output shaft 15. One end (the end on the left side in the figure) of the push rod 16A is connected to a clutch operation mechanism (e.g., a clutch operation lever) of the motorcycle (not shown), and the push rod 16A slides inside the hollow portion 15H by operating the clutch operation mechanism to press the push member 16B in the second direction D2. A part of the push member 16B protrudes outward from the output shaft 15 (here, in the second direction D2) and is connected to a release bearing 18 provided on the pressure plate 70. The push rod 16A and the push member 16B are formed to have a smaller inner diameter than the inner diameter of the hollow portion 15H, ensuring the flow of clutch oil within the hollow portion 15H.

[0019] The clutch housing 30 is made of an aluminum alloy. The clutch housing 30 is formed in a cylindrical shape with a bottom. As shown in FIG. 1, the clutch housing 30 has a bottom wall 31 formed in a substantially circular shape and a side wall 33 extending in a second direction D2 from an edge of the bottom wall 31. The clutch housing 30 holds a plurality of input side rotating plates 20. The clutch housing 30 holds the input side rotating plates 20 so that they can move relatively in the direction D but cannot move relatively in the circumferential direction S.

[0020] As shown in Fig. 1, an input gear 35 is provided on a bottom wall 31 of the clutch housing 30. The input gear 35 is fixed to the bottom wall 31 by a rivet 35B via a torque damper 35A. The input gear 35 meshes with a drive gear (not shown) that rotates by the rotational drive of the input shaft of the engine. The input gear 35 is rotated integrally with the clutch housing 30 independently of the output shaft 15.

[0021] The input side rotating plate 20 is rotationally driven by the rotational drive of the input shaft. As shown in Fig. 1, the input side rotating plate 20 is held on the inner circumferential surface of a side wall 33 of the clutch housing 30. The input side rotating plate 20 is held in the clutch housing 30 by spline fitting. The input side rotating plate 20 is provided so as to be displaceable along the axial direction of the clutch housing 30 (i.e., direction D). The input side rotating plate 20 is provided so as to be rotatable integrally with the clutch housing 30.

[0022] The input side rotating plate 20 is a member that is pressed against the output side rotating plate 22. The input side rotating plate 20 is formed in an annular shape. The input side rotating plate 20 is formed by aluminum die casting. Friction material (not shown) made of multiple pieces of paper is attached to the front and back surfaces of the input side rotating plate 20. Grooves several hundred μm deep are formed between the friction materials to hold clutch oil.

[0023] As shown in FIG. 1, the clutch center 40 is accommodated in the clutch housing 30. The clutch center 40 is arranged concentrically with the clutch housing 30. The clutch center 40 is made of an aluminum alloy. The clutch center 40 has a cylindrical main body 42 and a flange 68 extending radially outward from the outer periphery of the main body 42. The clutch center 40 holds the input side rotating plate 20 and a plurality of output side rotating plates 22 arranged alternately in the direction D. The clutch center 40 holds the output side rotating plates 22 so as to be relatively movable in the direction D and relatively immovable in the circumferential direction S. The clutch center 40 holds the input side rotating plate 20 so as to be relatively movable in the direction D and relatively movable in the circumferential direction S. The clutch center 40 rotates together with the output shaft 15.

[0024] As shown in FIG. 2, the main body 42 includes an annular base wall 43, an outer peripheral wall 45 located radially outward of the base wall 43 and extending toward the second direction D2, an output shaft holding portion 50 provided in the center of the base wall 43, a plurality of center side cam portions 60 connected to the base wall 43 and the outer peripheral wall 45, and a center side fitting portion 58.

[0025] The output shaft holding portion 50 is formed in a cylindrical shape. An insertion hole 51 into which the output shaft 15 is inserted and spline-fitted is formed in the output shaft holding portion 50. The insertion hole 51 is formed penetrating the base wall 43. An inner circumferential surface 50A of the output shaft holding portion 50 that forms the insertion hole 51 has a plurality of spline grooves formed along the axial direction. The output shaft 15 is connected to the output shaft holding portion 50.

[0026] As shown in FIG. 2, the outer peripheral wall 45 of the clutch center 40 is disposed radially outward of the output shaft holding portion 50. A spline fitting portion 46 is provided on an outer peripheral surface 45A of the outer peripheral wall 45. The spline fitting portion 46 has a plurality of center side fitting teeth 47 extending in the axial direction of the clutch center 40 along the outer peripheral surface 45A of the outer peripheral wall 45, a plurality of spline grooves 48 formed between adjacent center side fitting teeth 47 and extending in the axial direction of the clutch center 40, and an oil discharge hole 49. The center side fitting teeth 47 hold the output side rotating plate 22. The center side fitting teeth 47 hold the output side rotating plate 22 so that it can move relatively in the direction D and cannot move relatively in the circumferential direction S. The center side fitting teeth 47 are arranged in the circumferential direction S. The center side fitting teeth 47 are formed at equal intervals in the circumferential direction S. The center side fitting teeth 47 are formed in the same shape. The center side fitting teeth 47 protrude radially outward from the outer peripheral surface 45A of the outer peripheral wall 45. The oil discharge holes 49 are formed by penetrating the outer peripheral wall 45 in the radial direction. The oil discharge holes 49 are formed between the adjacent center side fitting teeth 47. That is, the oil discharge holes 49 are formed in the spline grooves 48. The oil discharge holes 49 are formed on the side of the center side cam portion 60. The oil discharge holes 49 are formed on the side of the center side slipper cam surface 60S of the center side cam portion 60. The oil discharge holes 49 are formed on the first circumferential direction S1 side of the center side slipper cam surface 60S. The oil discharge holes 49 are formed on the second circumferential direction S2 side of the boss portion 54 described later. In this embodiment, the oil discharge holes 49 are formed in threes at three locations in the circumferential direction S of the outer peripheral wall 45. The oil drain holes 49 are arranged at positions spaced at equal intervals in the circumferential direction S. The oil drain holes 49 communicate the inside and outside of the clutch center 40. The oil drain holes 49 are holes that drain the clutch oil that has flowed out from the output shaft 15 into the clutch center 40 to the outside of the clutch center 40. Here, the oil drain holes 49 drain the clutch oil flowing on the inner circumferential surface 45B side of the outer circumferential wall 45 to the outside of the clutch center 40. At least a portion of the oil drain holes 49 is provided in a position facing a pressure side fitting portion 88 described later.

[0027] The output side rotating plate 22 is held by the spline fitting portion 46 of the clutch center 40 and the pressure plate 70. A part of the output side rotating plate 22 is held by the clutch center 40. More specifically, a part of the output side rotating plate 22 is held by the center side fitting teeth 47 and the spline grooves 48 of the clutch center 40 by spline fitting. Another part of the output side rotating plate 22 is held by the pressure plate 70. More specifically, the other part of the output side rotating plate 22 is held by pressure side fitting teeth 77 (see FIG. 4 ) of the pressure plate 70, which will be described later. The output side rotating plate 22 is provided so as to be displaceable along the axial direction of the clutch center 40 (i.e., direction D). The output side rotating plate 22 is provided so as to be rotatable integrally with the clutch center 40.

[0028] The output side rotating plate 22 is a member pressed against the input side rotating plate 20. The output side rotating plate 22 is a flat plate formed in an annular shape. The output side rotating plate 22 is formed by punching a thin plate material made of SPCC material into an annular shape. The friction material provided on the input side rotating plate 20 may be provided on the output side rotating plate 22 instead of the input side rotating plate 20, or may be provided on both the input side rotating plate 20 and the output side rotating plate 22.

[0029] The center cam portion 60 is formed in a platform shape having a cam surface made of an inclined surface constituting an Assist & Slipper (registered trademark) mechanism that generates an assist torque, which is a force that increases the pressing force (pressure contact force) between the input side rotating plate 20 and the output side rotating plate 22, or a slipper torque, which is a force that causes the input side rotating plate 20 and the output side rotating plate 22 to separate early and transition to a half-clutch state. The center cam portion 60 is formed so as to protrude from the base wall 43 in the second direction D2. As shown in FIG. 3, the center cam portions 60 are disposed at equal intervals in the circumferential direction S of the clutch center 40. In this embodiment, the clutch center 40 has three center cam portions 60, but the number of center cam portions 60 is not limited to three.

[0030] As shown in FIG. 3, the center-side cam portion 60 is located radially outside the output shaft holding portion 50. The center-side cam portion 60 has a center-side assist cam surface 60A and a center-side slipper cam surface 60S. The center-side assist cam surface 60A is configured to generate a force in a direction that moves the pressure plate 70 closer to the clutch center 40 in order to increase the pressing force (pressing force) between the input side rotating plate 20 and the output side rotating plate 22 when the center-side assist cam surface 60A rotates relative to the pressure plate 70. In this embodiment, when the above force is generated, the position of the pressure plate 70 relative to the clutch center 40 does not change, and the pressure plate 70 does not need to physically approach the clutch center 40. Note that the pressure plate 70 may be physically displaced relative to the clutch center 40. The center-side slipper cam surface 60S is configured to move the pressure plate 70 away from the clutch center 40 in order to reduce the pressing force (pressure contact force) between the input-side rotating plate 20 and the output-side rotating plate 22 when rotating relative to the pressure plate 70. In the center-side cam portions 60 adjacent to each other in the circumferential direction S, the center-side assist cam surface 60A of one center-side cam portion 60L and the center-side slipper cam surface 60S of the other center-side cam portion 60M are disposed opposite each other in the circumferential direction S.

[0031] As shown in FIG. 2, the clutch center 40 has a plurality of boss portions 54 (three in this embodiment). The boss portions 54 are members that indirectly support the pressure plate 70. The boss portions 54 hold the pressure plate 70 via a stopper plate 100 (see FIG. 1) and a pressure spring 25 (see FIG. 1) described later. The plurality of boss portions 54 are disposed at equal intervals in the circumferential direction S. The boss portions 54 are formed in a cylindrical shape. The boss portions 54 are located radially outward from the output shaft holding portion 50. The boss portions 54 extend toward the pressure plate 70 (i.e., toward the second direction D2). The boss portions 54 are provided on the base wall 43. The boss portions 54 have a screw hole 54H formed therein, into which the bolts 28 (see FIG. 1) are inserted. The screw hole 54H extends in the axial direction of the clutch center 40.

[0032] 2 and 3, the clutch center 40 has a center-side cam hole 43H penetrating a portion of the base wall 43. The center-side cam hole 43H penetrates the base wall 43 in direction D. The center-side cam hole 43H extends from the side of the output shaft holding portion 50 to the outer peripheral wall 45. The center-side cam hole 43H is formed between the center-side assist cam surface 60A of the center-side cam portion 60 and the boss portion 54. When viewed from the axial direction of the clutch center 40, the center-side assist cam surface 60A and a portion of the center-side cam hole 43H overlap with each other.

[0033] As shown in FIG. 2, the center-side fitting portion 58 is located radially outward from the output shaft holding portion 50. The center-side fitting portion 58 is located radially outward from the center-side cam portion 60. The center-side fitting portion 58 is located in the second direction D2 from the center-side cam portion 60. The center-side fitting portion 58 is formed on the inner peripheral surface 45B of the outer peripheral wall 45. The center-side fitting portion 58 is configured to be slidably fitted to a pressure-side fitting portion 88 (see FIG. 4) described later. The inner diameter of the center-side fitting portion 58 is formed with a fitting tolerance that allows the clutch oil flowing out from the tip portion 15T (see FIG. 1) of the output shaft 15 to flow with respect to the pressure-side fitting portion 88. That is, a gap is formed between the center-side fitting portion 58 and the pressure-side fitting portion 88 described later.

[0034] As shown in FIG. 1, the pressure plate 70 is provided so as to be able to approach or separate from the clutch center 40 and to rotate relative thereto. The pressure plate 70 is configured so as to be able to press the input side rotating plate 20 and the output side rotating plate 22. The pressure plate 70 is arranged concentrically with the clutch center 40 and the clutch housing 30. The pressure plate 70 is formed of an aluminum alloy. The pressure plate 70 has a main body 72 and a flange 98 that is connected to the outer circumferential edge of the main body 72 in the second direction D2 and extends radially outward. The main body 72 protrudes in the first direction D1 beyond the flange 98. The pressure plate 70 holds a plurality of output side rotating plates 22 that are arranged alternately with the input side rotating plate 20. The pressure plate 70 holds the output side rotating plate 22 so as to be able to move relatively in the direction D and to be immovable relatively in the circumferential direction S. The pressure plate 70 holds the input side rotating plate 20 so as to be relatively movable in the direction D and in the circumferential direction S.

[0035] As shown in FIG. 4, the main body 72 includes a cylindrical portion 80, a plurality of pressure-side cam portions 90, a pressure-side fitting portion 88, and a spring accommodating portion 84 (see also FIG. 6).

[0036] As shown in Fig. 4, the flange 98 extends radially outward from the outer circumferential edge of the main body 72. Here, the flange 98 extends radially outward from the outer circumferential edge of the pressure-side fitting portion 88. The flange 98 has a pressing surface 98A that applies a pressing force to the input side rotating plate 20 and the output side rotating plate 22. The pressing surface 98A is a surface that directly or indirectly contacts the input side rotating plate 20 and the output side rotating plate 22. The pressing surface 98A sandwiches the input side rotating plate 20 and the output side rotating plate 22 between itself and the flange 68 of the clutch center 40.

[0037] The cylindrical portion 80 is formed in a cylindrical shape. The cylindrical portion 80 is formed integrally with the pressure side cam portion 90. The cylindrical portion 80 accommodates the tip portion 15T (see FIG. 1) of the output shaft 15. The cylindrical portion 80 accommodates the release bearing 18 (see FIG. 1). The cylindrical portion 80 is a portion that receives a pressing force from the push member 16B. The cylindrical portion 80 is a portion that receives the clutch oil that flows out from the tip portion 15T of the output shaft 15.

[0038] The pressure-side cam portion 90 is formed in a platform shape having a cam surface made of an inclined surface constituting an Assist & Slipper (registered trademark) mechanism that slides on the center-side cam portion 60 to generate an assist torque or a slipper torque. The pressure-side cam portion 90 is formed so as to protrude in a first direction D1 beyond the flange 98. As shown in FIG. 5, the pressure-side cam portions 90 are disposed at equal intervals in the circumferential direction S of the pressure plate 70. In this embodiment, the pressure plate 70 has three pressure-side cam portions 90, but the number of pressure-side cam portions 90 is not limited to three.

[0039] As shown in FIG. 5, the pressure-side cam portion 90 is located radially outside the cylindrical portion 80. The pressure-side cam portion 90 has a pressure-side assist cam surface 90A (see also FIG. 7) and a pressure-side slipper cam surface 90S. The pressure-side assist cam surface 90A is configured to be able to come into contact with the center-side assist cam surface 60A. The pressure-side assist cam surface 90A is configured to generate a force in a direction that moves the pressure plate 70 closer to the clutch center 40 in order to increase the pressing force (pressing force) between the input-side rotating plate 20 and the output-side rotating plate 22 when rotating relative to the clutch center 40. The pressure-side slipper cam surface 90S is configured to be able to come into contact with the center-side slipper cam surface 60S. The pressure-side slipper cam surface 90S is configured to move the pressure plate 70 away from the clutch center 40 in order to reduce the pressing force (pressure contact force) between the input side rotating plate 20 and the output side rotating plate 22 when rotating relative to the clutch center 40. In the pressure-side cam portions 90 adjacent to each other in the circumferential direction S, the pressure-side assist cam surface 90A of one pressure-side cam portion 90L and the pressure-side slipper cam surface 90S of the other pressure-side cam portion 90M are disposed opposite each other in the circumferential direction S.

[0040] Here, the action of the center side cam portion 60 and the pressure side cam portion 90 will be described. When the engine speed increases and the rotational driving force input to the input gear 35 and the clutch housing 30 can be transmitted to the output shaft 15 via the clutch center 40, a rotational force in the first circumferential direction S1 is applied to the pressure plate 70 as shown in Fig. 8A. Therefore, a force in the first direction D1 is generated on the pressure plate 70 due to the action of the center side assist cam surface 60A and the pressure side assist cam surface 90A. This increases the pressing force (pressing force) between the input side rotating plate 20 and the output side rotating plate 22.

[0041] On the other hand, when the rotation speed of the output shaft 15 exceeds the rotation speed of the input gear 35 and the clutch housing 30 and back torque is generated, a rotational force in the first circumferential direction S1 is applied to the clutch center 40 as shown in Fig. 8B. Therefore, the action of the center side slipper cam surface 60S and the pressure side slipper cam surface 90S moves the pressure plate 70 in the second direction D2 to release the pressing force (pressing force) between the input side rotating plate 20 and the output side rotating plate 22. This makes it possible to avoid malfunctions of the engine and the transmission due to back torque.

[0042] As shown in FIG. 4 and FIG. 5, the pressure plate 70 has a pressure side cam hole 73H penetrating a part of the main body 72 and the flange 98. The pressure side cam hole 73H is located radially outward from the cylindrical portion 80. The pressure side cam hole 73H extends from the side of the cylindrical portion 80 to a radially outward position from the pressure side fitting portion 88. The pressure side cam hole 73H is formed penetrating between the adjacent pressure side cam portions 90. The pressure side cam hole 73H is formed penetrating between the pressure side assist cam surface 90A and the pressure side slipper cam surface 90S of the adjacent pressure side cam portions 90. As shown in FIG. 5 and FIG. 7, when viewed from the axial direction of the pressure plate 70, the pressure side assist cam surface 90A and a part of the pressure side cam hole 73H overlap.

[0043] As shown in Figs. 6 and 7, the spring accommodating portion 84 is formed in the pressure-side cam portion 90. The spring accommodating portion 84 is formed so as to be recessed from the second direction D2 to the first direction D1. The spring accommodating portion 84 is formed in an elliptical shape. The spring accommodating portion 84 accommodates the pressure spring 25 (see Fig. 1). An insertion hole 84H into which the boss portion 54 (see Fig. 2) is inserted is formed through the spring accommodating portion 84. That is, the insertion hole 84H is formed through the pressure-side cam portion 90. The insertion hole 84H is formed in an elliptical shape.

[0044] 1, the pressure spring 25 is accommodated in the spring accommodating portion 84. The pressure spring 25 is held by the boss portion 54 inserted into the insertion hole 84H of the spring accommodating portion 84. The pressure spring 25 biases the pressure plate 70 toward the clutch center 40 (i.e., toward the first direction D1). The pressure spring 25 is, for example, a coil spring formed by winding spring steel in a spiral shape.

[0045] As shown in Fig. 4, the pressure side fitting portion 88 is provided on the main body 72. The pressure side fitting portion 88 is located radially outward from the pressure side cam portion 90. The pressure side fitting portion 88 is located in the second direction D2 from the pressure side cam portion 90. The pressure side fitting portion 88 is configured to be slidably fitted into the center side fitting portion 58 (see Fig. 2).

[0046] As shown in FIG. 4, the pressure plate 70 has a plurality of pressure side fitting teeth 77 formed on the flange 98. The pressure side fitting teeth 77 hold the output side rotating plate 22. The pressure side fitting teeth 77 hold the output side rotating plate 22 so that it can move relatively in the direction D and cannot move relatively in the circumferential direction S. The pressure side fitting teeth 77 hold the input side rotating plate 20. The pressure side fitting teeth 77 hold the input side rotating plate 20 so that it can move relatively in the direction D and can move relatively in the circumferential direction S. The pressure side fitting teeth 77 are located radially outward from the cylindrical portion 80. The pressure side fitting teeth 77 are located radially outward from the pressure side cam portion 90. The pressure side fitting teeth 77 are located radially outward from the pressure side fitting portion 88. The plurality of pressure side fitting teeth 77 are arranged in the circumferential direction S. The pressure side fitting teeth 77 are disposed at equal intervals in the circumferential direction S. In this embodiment, some of the pressure side fitting teeth 77 are removed, so the intervals in those portions are wider, but the other adjacent pressure side fitting teeth 77 are disposed at equal intervals.

[0047] As shown in Fig. 1, the stopper plate 100 is provided so as to be able to come into contact with the pressure plate 70. The stopper plate 100 is a member that prevents the pressure plate 70 from moving away from the clutch center 40 in the second direction D2 by more than a predetermined distance. The stopper plate 100 is fixed to the boss portion 54 of the clutch center 40 by the bolt 28. The pressure plate 70 is fixed by tightening the bolt 28 to the boss portion 54 via the stopper plate 100 in a state in which the boss portion 54 of the clutch center 40 and the pressure spring 25 are arranged in the spring accommodating portion 84. The stopper plate 100 is formed in a substantially triangular shape in a plan view.

[0048] As shown in FIG. 1, the disc spring 120 is held by the clutch center 40. The disc spring 120 is held by the center side fitting teeth 47 while abutting against the outer peripheral surface of the center side fitting teeth 47. The disc spring 120 is held by the center side fitting teeth 47 so as to be movable relative to the center side fitting teeth 47 in the direction D and in the circumferential direction S. The disc spring 120 is made of, for example, carbon steel. The disc spring 120 is aligned in the direction D with the output side rotating plate 22 held by the clutch center 40. The disc spring 120 is provided so as to be able to come into contact with the output side rotating plate 22 held by the clutch center 40. The disc spring 120 attenuates the pressing force in the direction from the pressure plate 70 toward the clutch center 40 (i.e., the first direction D1). The disc spring 120 is disposed between the output side rotating plates 22 adjacent to each other in the direction D held by the clutch center 40. The disc spring 120 is located in the second direction D2 from the center CL in the direction D from the first output side rotating plate 22A located furthest in the first direction D1 to the second output side rotating plate 22B located furthest in the second direction D2 among the multiple output side rotating plates 22 held by the clutch center 40. In this embodiment, the disc spring 120 is located between the third output side rotating plate 22C, which is located in the first direction D1 from the second output side rotating plate 22B among the multiple output side rotating plates 22 held by the clutch center 40 and adjacent to the second output side rotating plate 22B, and the second output side rotating plate 22B. The disc spring 120 is in contact with the second output side rotating plate 22B and the third output side rotating plate 22C. The input side rotating plate 20 is arranged radially outside the disc spring 120. The outer diameter of the disc spring 120 is smaller than the outer diameter of the output side rotating plate 22. In addition, since the disc springs 120 are disposed between the output side rotating plates 22, it is not necessary to dispose an iron sheet material between the disc springs 120 and the output side rotating plates 22.

[0049] A predetermined amount of clutch oil is filled inside the clutch device 10. The clutch oil flows through the hollow portion 15H of the output shaft 15 into the clutch center 40 and the pressure plate 70, and is then supplied to the input side rotating plate 20 and the output side rotating plate 22 through the gap between the center side fitting portion 58 and the pressure side fitting portion 88 and the oil discharge hole 49. The clutch oil absorbs heat and suppresses wear of the friction material. The clutch device 10 of this embodiment is a so-called wet-type multi-plate friction clutch device.

[0050] As described above, according to the clutch device 10 of this embodiment, the disc spring 120 held by the clutch center 40 is provided so as to be able to come into contact with the output side rotating plate 22 held by the clutch center 40, and is disposed between the output side rotating plates 22 adjacent to each other in the direction D held by the clutch center 40, and is located in the second direction D2 from the center CL of the direction D from the first output side rotating plate 22A to the second output side rotating plate 22B. According to the above aspect, the disc spring 120 is disposed at a position closer to the pressure plate 70 that generates the pressing force, and therefore the pressing force can be effectively attenuated. This makes it possible to suppress a sudden increase in the assist torque, and to suppress the sudden engagement of the clutch and the occurrence of vibration.

[0051] In the clutch device 10 of this embodiment, the disc spring 120 is located between the second output side rotating plate 22B and the third output side rotating plate 22C, which is located in the first direction D1 further than the second output side rotating plate 22B among the multiple output side rotating plates 22 held by the clutch center 40 and adjacent to the second output side rotating plate 22B. According to the above aspect, the disc spring 120 is disposed in a position closer to the pressure plate 70 that generates the pressing force, so that the pressing force can be attenuated more effectively.

[0052] In the clutch device 10 of the present embodiment, the disc spring 120 and the output side rotating plate 22 are held by the center side fitting teeth 47. According to the above-described aspect, the disc spring 120 and the output side rotating plate 22 are prevented from falling off the clutch center 40.

[0053] <Second embodiment> 9 is a cross-sectional view of a clutch device 210 according to the second embodiment. The clutch device 210 has a similar configuration to the clutch device 10, except that the disc spring 120 is disposed in a different position.

[0054] In the clutch device 210, the disc spring 120 is held by the pressure plate 70. The disc spring 120 is held by the pressure side fitting teeth 77 while abutting against the outer peripheral surface of the pressure side fitting teeth 77. The disc spring 120 is held by the pressure side fitting teeth 77 so as to be movable relative to the pressure side fitting teeth 77 in the direction D and in the circumferential direction S. The disc spring 120 is aligned in the direction D with the output side rotating plate 22 held by the pressure plate 70. The disc spring 120 is provided so as to be able to come into contact with the output side rotating plate 22 held by the pressure plate 70. In this embodiment, the disc spring 120 is disposed between the outermost output side rotating plate 22E located furthest in the second direction D2 among the output side rotating plates 22 held by the pressure plate 70 and the flange 98. More specifically, the disc spring 120 is disposed between the outermost output side rotating plate 22E and the pressing surface 98A of the flange 98. An iron sheet material 122 is disposed between the disc spring 120 and the flange 98. This prevents the disc spring 120 from coming into direct contact with the flange 98, thereby suppressing wear of the flange 98. The input side rotating plate 20 is disposed radially outward of the disc spring 120.

[0055] As described above, according to the clutch device 210 of this embodiment, the disc spring 120 held by the pressure plate 70 is arranged in the direction D with the output side rotating plate 22 held by the pressure plate 70, and is arranged so as to be able to come into contact with the output side rotating plate 22 held by the pressure plate 70. According to the above aspect, since the disc spring 120 is arranged on the pressure plate 70 which generates a pressing force, the pressing force can be effectively attenuated. This makes it possible to suppress a sudden increase in the assist torque, and suppress the occurrence of sudden engagement of the clutch and vibration.

[0056] In the clutch device 210 of this embodiment, the disc spring 120 is located between the flange 98 and the outermost output side rotating plate 22E, which is located furthest in the second direction D2 among the output side rotating plates 22 held by the pressure plate 70. According to the above aspect, since the disc spring 120 is located furthest in the second direction D2, the pressing force can be attenuated more effectively.

[0057] In the clutch device 210 of the present embodiment, the disc spring 120 and the output side rotating plate 22 are held by the pressure side fitting teeth 77. According to the above-described aspect, the disc spring 120 and the output side rotating plate 22 are prevented from falling off the pressure plate 70.

[0058] In the clutch device 210 of this embodiment, the clutch center 40 holds a part of the output side rotating plate 22, and the pressure plate 70 holds another part of the output side rotating plate 22. According to the above aspect, it is possible to adjust the force that is generated when the center side assist cam surface 60A and the pressure side assist cam surface 90A come into contact with each other, in a direction that moves the pressure plate 70 closer to the clutch center 40. For example, the force can be increased by increasing the number of output side rotating plates 22 held by the pressure plate 70.

[0059] Although the preferred embodiments of the present invention have been described above, the above-described embodiments are merely examples, and the present invention can be embodied in various other forms.

[0060] In each of the above-described embodiments, the clutch center 40 holds a part of the output side rotating plate 22, and the pressure plate 70 holds another part of the output side rotating plate 22, but this is not limited to the above. For example, the clutch center 40 may be configured to hold all of the output side rotating plates 22, or the pressure plate 70 may be configured to hold all of the output side rotating plates 22.

[0061] In the above-described second embodiment, the disc spring 120 is disposed between the flange 98 and the output side rotating plate 22, but this is not limited thereto. For example, in a case where the pressure plate 70 holds a plurality of output side rotating plates 22, the disc spring 120 may be disposed between adjacent output side rotating plates 22 held by the pressure plate 70. [Explanation of symbols]

[0062] 10 Clutch device 15 Output shaft 20 Input side rotating plate 22 Output side rotating plate 30 Clutch housing 40 Clutch center 45 Outer wall 47 Center side mating teeth 50 Output shaft holder 60 Center side cam part 60A Center side assist cam surface 60S Center side slipper cam surface 70 Pressure Plate 72 Main Body 77 Pressure side mating teeth 90 Pressure side cam part 90A Pressure side assist cam surface 90S Pressure side slipper cam surface 98 Flange 120 Disc spring

Claims

1. A clutch device that transmits or cuts off the rotational driving force of an input shaft to an output shaft, a clutch center that is accommodated in a clutch housing that holds a plurality of input side rotating plates that are rotationally driven by the rotational drive of the input shaft, holds a plurality of output side rotating plates that are arranged alternately with the input side rotating plates, and is rotationally driven together with the output shaft; a pressure plate that is provided so as to be capable of approaching or separating from the clutch center and rotatable relative to the clutch center and that is capable of pressing the input side rotating plate and the output side rotating plate; A disc spring held by the clutch center, The clutch center is a center-side cam portion having a center-side assist cam surface that generates a force in a direction that moves the pressure plate closer to the clutch center in order to increase a pressing force between the input side rotating plate and the output side rotating plate when the center-side cam portion rotates relative to the pressure plate, The pressure plate is a pressure-side cam portion having a pressure-side assist cam surface that generates a force in a direction that brings the pressure plate closer to the clutch center in order to increase a pressing force between the input side rotating plate and the output side rotating plate when the pressure plate rotates relative to the clutch center, When the direction in which the pressure plate moves is defined as a moving direction, the direction in which the pressure plate approaches the clutch center is defined as a first direction, and the direction in which the pressure plate moves away from the clutch center is defined as a second direction, A clutch device, wherein the disc spring is arranged so as to be able to come into contact with the output side rotating plate held by the clutch center, and is disposed between adjacent output side rotating plates held by the clutch center in the moving direction, and is positioned in the second direction further than the center of the moving direction from a first output side rotating plate that is located furthest in the first direction to a second output side rotating plate that is located furthest in the second direction among the multiple output side rotating plates held by the clutch center.

2. 2. The clutch device as described in claim 1, wherein the disc spring is positioned between a third output side rotating plate among the multiple output side rotating plates held by the clutch center, the third output side rotating plate being positioned in the first direction further than the second output side rotating plate and adjacent to the second output side rotating plate, and the second output side rotating plate.

3. The clutch center is an output shaft holding portion to which the output shaft is connected; an outer circumferential wall located radially outward of the output shaft holding portion; a plurality of center side fitting teeth arranged in a circumferential direction and formed so as to protrude radially outward from an outer circumferential surface of the outer circumferential wall; a plurality of spline grooves formed between adjacent center side fitting teeth, 3. The clutch device according to claim 1, wherein the disc spring and the output side rotary plate are held by the center side mating teeth.

4. A clutch device that transmits or cuts off the rotational driving force of an input shaft to an output shaft, a clutch center that is accommodated in a clutch housing that holds a plurality of input side rotary plates that are rotationally driven by the rotational drive of the input shaft, and that is rotationally driven together with the output shaft; a pressure plate that is provided so as to be capable of approaching or separating from the clutch center and rotatable relative to the clutch center, that holds at least a portion of a plurality of output side rotating plates that are arranged alternately with the input side rotating plate, and that can press the input side rotating plate and the output side rotating plate; a disc spring held by the pressure plate; The clutch center is a center-side cam portion having a center-side assist cam surface that generates a force in a direction that moves the pressure plate closer to the clutch center in order to increase a pressing force between the input side rotating plate and the output side rotating plate when the center-side cam portion rotates relative to the pressure plate, The pressure plate is a pressure-side cam portion having a pressure-side assist cam surface that generates a force in a direction that brings the pressure plate closer to the clutch center in order to increase a pressing force between the input side rotating plate and the output side rotating plate when the pressure plate rotates relative to the clutch center, When the direction in which the pressure plate moves is defined as the moving direction, A clutch device, wherein the disc spring is aligned with the output side rotating plate held by the pressure plate in the movement direction and is arranged to be able to come into contact with the output side rotating plate held by the pressure plate.

5. The pressure plate is The main body, a flange extending radially outward from an outer periphery of the body; When a direction in which the pressure plate approaches the clutch center is defined as a first direction, and a direction in which the pressure plate moves away from the clutch center is defined as a second direction, 5. The clutch device according to claim 4, wherein the disc spring is positioned between the flange and an outermost output side rotating plate that is positioned furthest in the second direction among the output side rotating plates held by the pressure plate.

6. The pressure plate includes a plurality of pressure-side fitting teeth arranged in a circumferential direction, 6. The clutch device according to claim 4, wherein the disc spring and the output side rotary plate are held by the pressure side fitting teeth.

7. The clutch center holds a portion of the output side rotating plate, 6. The clutch device according to claim 4, wherein the pressure plate holds another part of the output side rotary plate.

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