Clutch device

Abstract

To provide a clutch device which achieves weight saving of a clutch housing and in which circulation of a clutch oil can be performed more smoothly.SOLUTION: A clutch device 10 includes a clutch housing 30 which rotates integrally with an input gear 35, and which holds a plurality of input side rotary plates 20. The clutch housing 30 includes: a first groove part 36 provided at a side wall 33, and for holding the plurality of input side rotary plates 20; a second groove part 37 provided at the side wall 33, adjacent to the first groove part 36 regarding a circumferential direction S, and for holding an outermost input side rotary plate 20X which is positioned furthest on the first direction D1 side out of the plurality of input side rotary plates 20; and a third groove part 38 dented from an end part 37D2 in the second direction D2 of the second groove part 37 to the second direction D2, and for not holding the input side rotary plate 20 or the outermost input side rotary plate 20X.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Straddle-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 drive wheel. For example, Patent Document 1 discloses a wet multi-plate clutch (hereinafter referred to as a clutch device) that has an input gear that meshes with the drive gear of the engine, a clutch outer (hereinafter referred to as a clutch housing) that rotates integrally with the input gear, a clutch inner (hereinafter referred to as a clutch center) connected to an output shaft, and a pressure plate (hereinafter referred to as a pressure plate) that can move toward or away from the clutch center.

[0003] The clutch housing of Patent Document 1 has multiple main spline grooves that hold the driving friction plates (hereinafter referred to as input side rotating plates) and multiple auxiliary spline grooves that hold the input side rotating plate (hereinafter referred to as the outermost input side rotating plate) that is located on the outermost side of the input side rotating plates, formed alternately in the circumferential direction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4648237 Summary of the Invention [Problem to be solved by the invention]

[0005] In the clutch housing of Patent Document 1, the tips of the many fins are connected together with an annular connecting portion to increase rigidity, and the auxiliary spline grooves that hold the outermost input-side rotating plate are formed by removing part of the fins. This can make the clutch housing relatively heavy. Furthermore, because clutch oil circulates inside the clutch housing, it is preferable for the clutch oil to circulate more smoothly between the inside and outside of the clutch housing.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to provide a clutch device that realizes a reduction in the weight of the clutch housing and allows clutch oil to circulate more smoothly. [Means for solving the problem]

[0007] The clutch device according to the present invention is a clutch device that transmits or cuts off the rotational drive force of an input shaft to an output shaft, and includes: a gear that is rotationally driven by the rotational drive of the input shaft; a clutch housing that rotates integrally with the gear and holds a plurality of input side rotating plates; a clutch center that is accommodated in the clutch housing and rotationally driven together with the output shaft; and 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 that can press the input side rotating plate and a plurality of output side rotating plates that are arranged alternately with the input side rotating plate. The clutch housing has a ring-shaped bottom wall to which the gear is attached, and a pressure plate that is configured such that a direction from one side to the other in the axial direction of the output shaft is defined as a first direction and a direction from the other side to the one side is defined as a second direction. and a first groove portion provided on the side wall, recessed from the end of the side wall in the first direction in the second direction, at least a portion of which penetrates radially, and holding the plurality of input side rotating plates; a second groove portion provided on the side wall, adjacent to the first groove portion in the circumferential direction, recessed from the end of the side wall in the first direction in the second direction, and holding at least an outermost input side rotating plate which is located furthest to the first direction among the plurality of input side rotating plates; and a third groove portion provided on the side wall, recessed from the end of the second groove portion in the second direction in the second direction, at least a portion of which penetrates radially, and not holding the input side rotating plate or the outermost input side rotating plate.

[0008] In the clutch device according to the present invention, the first groove portion that holds the multiple input rotating plates is recessed in a second direction from the end of the side wall in the first direction and at least partially penetrates in the radial direction. The second groove portion that holds the outermost input rotating plate is recessed in the second direction from the end of the side wall in the first direction. The third groove portion that does not hold the input rotating plate or the outermost input rotating plate is recessed in the second direction from the end of the second groove portion in the second direction and at least partially penetrates in the radial direction. According to the above aspect, the first, second, and third groove portions are provided in the side wall, thereby achieving a lightweight clutch housing. Furthermore, since the third groove portion also penetrates in the radial direction in addition to the first groove portion, clutch oil circulates more smoothly between the inside and outside of the clutch housing. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a clutch device that realizes a reduction in the weight of the clutch housing and allows clutch oil to circulate more smoothly. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of a clutch device according to one embodiment. [Figure 2] FIG. 2 is a plan view of an input side rotating plate according to one embodiment. [Figure 3] FIG. 3 is a perspective view of a clutch housing according to one embodiment. [Figure 4] FIG. 4 is a plan view of a clutch housing according to one embodiment. [Figure 5] FIG. 5 is a view taken along the arrow V in FIG. [Figure 6] FIG. 6 is a view taken along the arrow VI in FIG. [Figure 7] FIG. 7 is a perspective view of a clutch center according to one embodiment. [Figure 8] FIG. 8 is a perspective view of a clutch center according to one embodiment. [Figure 9]FIG. 9 is a perspective view of a pressure plate according to one embodiment. [Figure 10A] FIG. 10A is a schematic diagram illustrating the action of the center-side assist cam surface and the pressure-side assist cam surface. [Figure 10B] FIG. 10B is a schematic diagram illustrating the action of the center-side slipper cam surface and the pressure-side slipper cam surface. [Figure 11] FIG. 11 is a perspective view of a clutch housing according to another embodiment. [Figure 12] FIG. 12 is a plan view of a clutch housing according to another embodiment. [Figure 13] FIG. 13 is a view taken along the arrow XIII in FIG. [Figure 14] FIG. 14 is a view taken along the arrow XIV in FIG. [Figure 15] FIG. 15 is a view taken along the arrow XV in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of a clutch device according to the present invention will be described with reference to the drawings. It should be noted that the embodiment described here is not intended to limit the present invention in any particular way. Furthermore, the same reference numerals are used to designate members and parts that perform the same functions, and redundant descriptions will be omitted or simplified as appropriate.

[0012] First Embodiment FIG. 1 is a cross-sectional view of a clutch device 10 according to a first embodiment. The clutch device 10 is provided on a 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 of the motorcycle to an output shaft 15, for example. The clutch device 10 is a device that transmits or cuts off the rotational driving force of the input shaft to driving wheels (rear wheels) via the output shaft 15. The clutch device 10 is disposed between the engine and a transmission. The clutch device 10 includes an input gear 35, a clutch housing 30, a clutch center 40, a pressure plate 70, and a lifter plate 100.

[0013] In the following description, the axial direction of the output shaft 15 is referred to as direction D, the direction from one side to the other with respect to direction D is referred to as first direction D1, and the direction from the other side to the one side with respect to direction D is referred to as second direction D2. The circumferential direction of the clutch center 40 and the pressure plate 70 is referred to as circumferential direction S, the direction from one side to the other with respect to circumferential direction S is referred to as first circumferential direction S1 (see FIG. 3), and the direction from the other side to the one side with respect to circumferential direction S is referred to as second circumferential direction S2 (see FIG. 3). In this embodiment, the axial direction of the clutch housing 30, the axial direction of the clutch center 40, and the axial direction of the pressure plate 70 are the same as direction D. The pressure plate 70 and the clutch center 40 rotate in the first circumferential direction S1. 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.

[0014] As shown in Fig. 1, the output shaft 15 is a hollow shaft body. The end of the output shaft 15 on the first direction D1 side rotatably supports the input gear 35 and the clutch housing 30 via a bearing 15A. The output shaft 15 fixedly supports the clutch center 40 via a collar 15C and a nut 15N. That is, the output shaft 15 rotates integrally with the clutch center 40. The end of the output shaft 15 on the second direction D2 side is connected to, for example, a transmission (not shown) of a motorcycle.

[0015] 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. 3, the clutch housing 30 has a ring-shaped bottom wall 31 and a side wall 33 extending from the outer periphery of the bottom wall 31 in a first direction D1. The clutch housing 30 holds a plurality of input side rotating plates 20 (see FIG. 2). A detailed description of the clutch housing 30 will be given later.

[0016] As shown in FIG. 1, an input gear 35 is attached to the 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 when the input shaft of the engine is rotated. The input gear 35 is rotated when the input shaft is rotated. The input gear 35 rotates integrally with the clutch housing 30, independent of the output shaft 15. The input gear 35 is an example of a gear.

[0017] As shown in FIG. 1, the input side rotating plate 20 is held by the clutch housing 30. 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 rotationally driven by the rotational drive of the input shaft. The input side rotating plate 20 is provided so as to be rotatable integrally with the clutch housing 30.

[0018] The input side rotating plate 20 is a member that is pressed against the output side rotating plate 22. As shown in FIG. 2, the input side rotating plate 20 has a ring-shaped main body 20A and a plurality of claws 20B that extend radially outward from the outer periphery of the main body 20A. The input side rotating plate 20 is formed by aluminum die-casting. The input side rotating plate 20 has a plurality of friction materials 20C provided on the front and back surfaces of the main body 20A. The friction materials 20C are made of paper pieces. The plurality of friction materials 20C are arranged at equal intervals in the circumferential direction S. The input side rotating plate 20 has a plurality of oil grooves 20D formed between adjacent friction materials 20C. The oil grooves 20D are grooves for retaining clutch oil. The depth of the oil grooves 20D is several tens to several hundreds of μm.

[0019] As shown in FIGS. 3 and 4 , the clutch housing 30 has a first groove 36. The first groove 36 is provided in the side wall 33. The first groove 36 is recessed in the second direction D2 from an end 33D1 of the side wall 33 in the first direction D1. The first groove 36 penetrates in the radial direction. The first groove 36 penetrates the side wall 33 in the radial direction. The multiple first grooves 36 are provided at equal intervals in the circumferential direction S. The first groove 36 holds multiple input side rotating plates 20. The claw portions 20B of the input side rotating plate 20 engage with the first groove 36. As shown in FIG. 1 , in this embodiment, the first groove 36 holds three input side rotating plates 20, but the number is not limited to three.

[0020] As shown in FIGS. 3 and 4 , the clutch housing 30 includes second grooves 37. The second grooves 37 are provided in the sidewall 33. The second grooves 37 are adjacent to the first grooves 36 in the circumferential direction S. The second grooves 37 are provided alternately with the first grooves 36 in the circumferential direction S. The second grooves 37 are recessed in the second direction D2 from an end 33D1 of the sidewall 33 in the first direction D1. The second grooves 37 penetrate radially. The second grooves 37 penetrate the sidewall 33 radially. The multiple second grooves 37 are provided at equal intervals in the circumferential direction S. As shown in FIG. 1 , the second grooves 37 hold the outermost input rotating plate 20X, which is located furthest in the first direction D1, among the multiple input rotating plates 20. The second grooves 37 hold only the outermost input rotating plate 20X among the multiple input rotating plates 20. The claw portions 20B of the outermost input side rotating plate 20X are engaged with the second groove portions 37. The outermost input side rotating plate 20X is not engaged with the first groove portions .

[0021] As shown in FIGS. 3 and 4 , the clutch housing 30 has a third groove portion 38. The third groove portion 38 is provided in the side wall 33. The third groove portion 38 is adjacent to the first groove portion 36 in the circumferential direction S. The third groove portion 38 is recessed in the second direction D2 from the end of the second groove portion 37 in the second direction D2. The third groove portion 38 is continuous with the second groove portion 37. The third groove portion 38 penetrates in the radial direction. The third groove portion 38 penetrates the side wall 33 in the radial direction. The multiple third groove portions 38 are provided at equal intervals in the circumferential direction S. As shown in FIG. 1 , the multiple input side rotating plates 20 and the outermost input side rotating plate 20X are not held by the third groove portion 38. The claw portions 20B of the input side rotating plate 20 do not engage with the third groove portion 38.

[0022] As shown in Figures 3 and 4, the clutch housing 30 has a fourth groove portion 39. The fourth groove portion 39 is provided in the side wall 33. The fourth groove portion 39 is adjacent to the first groove portion 36 in the circumferential direction S. At least a portion of the fourth groove portion 39 is recessed in the second direction D2 from an end of the third groove portion 38 in the second direction D2. In this embodiment, a portion of the fourth groove portion 39 is located to the side of the third groove portion 38 in the circumferential direction S. The fourth groove portion 39 is continuous with the third groove portion 38. The fourth groove portion 39 is recessed in the radial direction. The fourth groove portion 39 is recessed from the radially inner side of the side wall 33 to the radially outer side. The fourth groove portion 39 does not penetrate the side wall 33. The multiple fourth groove portions 39 are provided at equal intervals in the circumferential direction S. 1, the fourth groove 39 does not hold the input side rotating plates 20 and the outermost input side rotating plate 20X. The fourth groove 39 does not engage with the claws 20B of the input side rotating plate 20.

[0023] 3, the clutch housing 30 has a step portion 34 provided between the second groove portion 37 and the third groove portion 38. The step portion 34 is provided so as to be able to come into contact with a part of the outermost input side rotating plate 20X.

[0024] As shown in FIGS. 5 and 6 , the length P2 in the circumferential direction S of the second groove portion 37 is shorter than the length P1 in the circumferential direction S of the first groove portion 36. The length P3 in the circumferential direction S of the third groove portion 38 is shorter than the length P1 in the circumferential direction S of the first groove portion 36. The length P3 in the circumferential direction S of the third groove portion 38 is shorter than the length P2 in the circumferential direction S of the second groove portion 37. The length P3 in the circumferential direction S of the third groove portion 38 is shorter than the length P4 in the circumferential direction S of the fourth groove portion 39. The length P4 in the circumferential direction S of the fourth groove portion 39 is shorter than the length P1 in the circumferential direction S of the first groove portion 36. The length P4 in the circumferential direction S of the fourth groove portion 39 is shorter than the length P2 in the circumferential direction S of the second groove portion 37. Note that the length P2 may be shorter than or the same as the length P3. The length P4 may be shorter than or the same as the length P3. In this embodiment, the length P1 and the length P2 are longer than a length P5 (see FIG. 2) in the circumferential direction S of the claw portion 20B of the input side rotating plate 20. The length P3 is shorter than the length P5.

[0025] As shown in Figures 5 and 6, when the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 36D2 of the first groove portion 36 in the second direction D2 is L1, the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 37D2 of the second groove portion 37 in the second direction D2 is L2, the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 38D2 of the third groove portion 38 in the second direction D2 is L3, and the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 39D2 of the fourth groove portion 39 in the second direction D2 is L4, the relationship L1>L4>L3>L2 is satisfied. The length L2 is shorter than the length L5 from the end 37D2 of the second groove 37 in the second direction D2 to the end 38D2 of the third groove 38 in the second direction D2 (ie, the length of the third groove 38 in the direction D).

[0026] As shown in FIG. 1, the clutch center 40 is accommodated in the clutch housing 30. The clutch center 40 is disposed concentrically with the clutch housing 30. The clutch center 40 has a cylindrical main body 42 and a flange 68 extending radially outward from the outer peripheral edge of the main body 42. The main body 42 protrudes in the second direction D2 beyond the flange 68. 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 is driven to rotate together with the output shaft 15.

[0027] As shown in Figure 7, the main body 42 includes an output shaft holding portion 50 provided in the center of the main body 42, an outer peripheral wall 45 located radially outward from the output shaft holding portion 50, and a plurality of center-side cam portions 60 connected to the output shaft holding portion 50 and the outer peripheral wall 45.

[0028] As shown in FIG. 7 , the output shaft holding portion 50 is formed in a cylindrical shape. The output shaft holding portion 50 extends in the second direction D2. The end of the output shaft holding portion 50 on the second direction D2 side is located closer to the second direction D2 than the center-side cam portion 60. An insertion hole 51 is formed through the output shaft holding portion 50, into which the output shaft 15 is inserted and spline-fitted. 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.

[0029] As shown in FIG. 7 , a spline fitting portion 46 is provided on the 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, and 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. The center-side fitting teeth 47 hold the output-side rotating plate 22. The center-side fitting teeth 47 are aligned 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 to have the same shape. The center-side fitting teeth 47 protrude radially outward from the outer peripheral surface 45A of the outer peripheral wall 45.

[0030] The output side rotating plate 22 is held by a spline fitting portion 46 of the clutch center 40 and a spline fitting portion 76 of the pressure plate 70, which will be described later. A portion of the output side rotating plate 22 is held by spline fitting to center side fitting teeth 47 and spline grooves 48 of the clutch center 40. Another portion of the output side rotating plate 22 is held by spline fitting to pressure side fitting teeth 77 (see FIG. 9) and spline grooves 78 (see FIG. 9), which will be described later, of the pressure plate 70. The output side rotating plate 22 is provided so as to be displaceable along the axial direction of the clutch center 40. The output side rotating plate 22 is provided so as to be rotatable integrally with the clutch center 40.

[0031] The output side rotating plate 22 is a member that is pressed against the input side rotating plate 20. The output side rotating plate 22 is formed in a ring shape. The output side rotating plate 22 is formed by punching out a thin plate material made of SPCC material into a ring shape. Note that the friction material 20C (see FIG. 2) 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.

[0032] The center-side cam portion 60 is formed in a platform shape having a cam surface made of an inclined surface that constitutes 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 quickly separates the input-side rotating plate 20 and the output-side rotating plate 22, causing the clutch to transition to a half-clutch state. The center-side cam portion 60 is formed on the main body 42. An end of the center-side cam portion 60 on the second direction D2 side is located closer to the second direction D2 than the outer peripheral wall 45. The center-side cam portions 60 are arranged at equal intervals in the circumferential direction S of the clutch center 40. In this embodiment, the clutch center 40 has three center-side cam portions 60, but the number of center-side cam portions 60 is not limited to three.

[0033] As shown in FIG. 7 , the center-side cam portion 60 is located radially outward of 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 from the pressure plate 70 toward the clutch center 40 in order to increase the pressing force (pressure contact force) between the input-side rotating plate 20 and the output-side rotating plate 22 when the clutch center 40 rotates relative to the pressure plate 70. In this embodiment, when the 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 the clutch center 40 rotates 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 arranged opposite each other in the circumferential direction S.

[0034] As shown in FIG. 8, the clutch center 40 has a spring accommodating portion 54. The spring accommodating portion 54 is formed in the main body 42. More specifically, the spring accommodating portion 54 is formed in the center-side cam portion 60. The spring accommodating portion 54 accommodates the pressure spring 25 (see FIG. 1). In this embodiment, the clutch center 40 has three spring accommodating portions 54. The three spring accommodating portions 54 are arranged at equal intervals in the circumferential direction S of the clutch center 40. The number of spring accommodating portions 54 is not limited to three. The spring accommodating portion 54 is located on the second circumferential direction S2 side of the center-side slipper cam surface 60S. The spring accommodating portion 54 is located on the first circumferential direction S1 side of the center-side assist cam surface 60A.

[0035] As shown in FIG. 1, the pressure spring 25 is accommodated in the spring accommodating portion 54. An end 25D1 of the pressure spring 25 in the first direction D1 contacts the lifter plate 100. An end 25D2 of the pressure spring 25 in the second direction D2 contacts the clutch center 40. The pressure spring 25 biases the pressure plate 70 in a direction toward the clutch center 40 with respect to the direction D (i.e., the first direction D1). The pressure spring 25 is, for example, a coil spring formed by spirally winding spring steel.

[0036] As shown in Figures 7 and 8, the clutch center 40 has a center-side cam hole 43H that penetrates a portion of the main body 42. The center-side cam hole 43H penetrates the main body 42 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 and the center-side slipper cam surface 60S of the adjacent center-side cam portion 60. A boss portion 84 (see Figure 9), described later, of the pressure plate 70 is inserted into the center-side cam hole 43H. When viewed in 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.

[0037] As shown in FIG. 1 , the pressure plate 70 is housed in the clutch housing 30. The pressure plate 70 is located between the clutch housing 30 and the clutch center 40. The pressure plate 70 is provided to be movable in direction D. The pressure plate 70 is provided to be able to move toward or away from the clutch center 40 and to be able to rotate relative to the clutch center 40. The pressure plate 70 is configured 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 has a main body 72 and a flange 98 that connects to the outer peripheral edge of the main body 72 on the second direction D2 side 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 plates 20.

[0038] As shown in Figure 9, the main body 72 includes an annular base wall 73, a fitting hole 80 provided in the center of the base wall 73, an outer peripheral wall 75 located radially outside the base wall 73 and extending toward the first direction D1, and a plurality of pressure side cam portions 90 connected to the base wall 73 and the outer peripheral wall 75.

[0039] 9, the flange 98 extends radially outward from the outer circumferential edge of the main body 72. The flange 98, together with the flange 68 of the clutch center 40, sandwiches the input side rotating plate 20 and the output side rotating plate 22. The flange 98 is a member that applies a pressing force to the input side rotating plate 20 and the output side rotating plate 22.

[0040] 9, the fitting hole 80 is formed in the center of the main body 72. The fitting hole 80 penetrates the base wall 73 in direction D. The output shaft holding portion 50 of the clutch center 40 is inserted into the fitting hole 80.

[0041] As shown in FIG. 9 , a spline fitting portion 76 is provided on the outer peripheral surface 75A of the outer peripheral wall 75. The spline fitting portion 76 has a plurality of pressure-side fitting teeth 77 extending in the axial direction of the pressure plate 70 along the outer peripheral surface 75A of the outer peripheral wall 75, and a plurality of spline grooves 78 formed between adjacent pressure-side fitting teeth 77 and extending in the axial direction of the pressure plate 70. The pressure-side fitting teeth 77 hold the output-side rotating plate 22. The plurality of pressure-side fitting teeth 77 are aligned in the circumferential direction S. The plurality of pressure-side fitting teeth 77 are formed to have the same shape. The pressure-side fitting teeth 77 protrude radially outward from the outer peripheral surface 75A of the outer peripheral wall 75.

[0042] The pressure-side cam portion 90 is formed in a platform shape having a cam surface made up of an inclined surface that constitutes an Assist & Slipper (registered trademark) mechanism that slides on the center-side cam portion 60 to generate assist torque or slipper torque. The pressure-side cam portion 90 is formed so as to protrude in the first direction D1 beyond the flange 98. As shown in FIG. 9 , the pressure-side cam portions 90 are arranged 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.

[0043] As shown in FIG. 9 , the pressure-side cam portion 90 is located radially outward of the fitting hole 80. The pressure-side cam portion 90 has a pressure-side assist cam surface 90A 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 from the pressure plate 70 toward the clutch center 40 in order to increase the pressing force (pressure contact force) between the input-side rotating plate 20 and the output-side rotating plate 22 when the pressure plate 70 rotates 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 the pressure plate 70 rotates 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 arranged opposite each other in the circumferential direction S.

[0044] 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. 10A. Therefore, due to the action of the center-side assist cam surface 60A and the pressure-side assist cam surface 90A, a force in the first direction D1 is generated on the pressure plate 70. This increases the pressing force between the input-side rotating plate 20 and the output-side rotating plate 22.

[0045] 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. 10B. As a result, 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, releasing the pressure contact force between the input-side rotating plate 20 and the output-side rotating plate 22. This makes it possible to avoid problems with the engine and transmission due to back torque.

[0046] As shown in FIG. 9 , the pressure plate 70 has a pressure-side cam hole 73H penetrating a portion of the base wall 73. The pressure-side cam hole 73H penetrates the base wall 73 in direction D. The pressure-side cam hole 73H is located radially outward of the fitting hole 80. The pressure-side cam hole 73H extends from the side of the fitting hole 80 to the outer peripheral wall 75. The pressure-side cam hole 73H is formed to penetrate between adjacent pressure-side cam portions 90. The pressure-side cam hole 73H is formed to penetrate between the pressure-side assist cam surface 90A and the pressure-side slipper cam surface 90S of adjacent pressure-side cam portions 90. When viewed in the axial direction of the pressure plate 70, the pressure-side assist cam surface 90A and a portion of the pressure-side cam hole 73H overlap.

[0047] As shown in FIG. 9 , the pressure plate 70 has a plurality of boss portions 84 (three in this embodiment). The plurality of boss portions 84 are arranged at equal intervals in the circumferential direction S. The boss portions 84 are formed in a cylindrical shape. The boss portions 84 are located radially outward from the fitting hole 80. The boss portions 84 extend from the base wall 73 in the first direction D1. The boss portions 84 are provided on the pressure-side cam portion 90. The boss portions 84 are located between the pressure-side assist cam surface 90A and the pressure-side slipper cam surface 90S in the circumferential direction S. The boss portions 84 are inserted into the center-side cam hole 43H (see FIG. 1 ). A threaded hole 84H is formed in the boss portion 84, and the bolt 28 (see FIG. 1 ) is inserted into the boss portion 84. The threaded hole 84H extends in the axial direction of the pressure plate 70.

[0048] As shown in FIG. 1 , the lifter plate 100 is a member for displacing the pressure plate 70 in direction D. The lifter plate 100 is fixed to the pressure plate 70 by bolts 28. The lifter plate 100 rotates integrally with the pressure plate 70. The lifter plate 100 moves integrally with the pressure plate 70 in direction D. The lifter plate 100 moves in direction D relative to the clutch center 40 and rotates relative to the clutch center 40. The lifter plate 100 is operated by a clutch release mechanism (not shown). Here, the clutch release mechanism is a mechanical device that is operated by the driver's operation of a clutch operating lever (not shown) in a vehicle such as a motorcycle on which the clutch device 10 is mounted.

[0049] As described above, in the clutch device 10 of this embodiment, the first grooves 36 that hold the multiple input rotating plates 20 are recessed in the second direction D2 from the end 33D1 of the sidewall 33 in the first direction D1 and penetrate radially. The second grooves 37 that hold the outermost input rotating plates 20X are recessed in the second direction D2 from the end 33D1 of the sidewall 33 in the first direction D1. The third grooves 38 that do not hold the input rotating plates 20 or the outermost input rotating plates 20X are recessed in the second direction D2 from the end 37D2 of the second grooves 37 in the second direction D2 and penetrate radially. According to the above aspect, the first grooves 36, the second grooves 37, and the third grooves 38 are provided in the sidewall 33, thereby achieving a reduction in the weight of the clutch housing 30. Furthermore, in addition to the first groove portion 36, the third groove portion 38 also penetrates in the radial direction, so that the clutch oil circulates more smoothly between the inside and outside of the clutch housing 30.

[0050] In the clutch device 10 of this embodiment, the clutch housing 30 includes a fourth groove portion 39 that is provided in the side wall 33 and that is at least partially recessed in the second direction D2 and radially from an end portion 38D2 in the second direction D2 of the third groove portion 38. According to the above aspect, the fourth groove portion 39 is provided in the side wall 33, thereby achieving further weight reduction of the clutch housing 30. Note that the fourth groove portion 39 does not penetrate in the radial direction, and therefore the rigidity of the side wall 33 can be ensured.

[0051] In the clutch device 10 of this embodiment, the length P3 in the circumferential direction S of the third groove portion 38 is shorter than the length P2 in the circumferential direction S of the second groove portion 37. According to the above aspect, the rigidity of the side wall 33 can be increased.

[0052] In the clutch device 10 of this embodiment, the length P3 of the third groove portion 38 in the circumferential direction S is shorter than the length P4 of the fourth groove portion 39 in the circumferential direction S. According to the above aspect, the rigidity of the side wall 33 can be increased.

[0053] In the clutch device 10 of this embodiment, the length P2 in the circumferential direction S of the second groove portion 37, the length P3 in the circumferential direction S of the third groove portion 38, and the length P4 in the circumferential direction S of the fourth groove portion 39 are shorter than the length P1 in the circumferential direction S of the first groove portion 36. According to the above aspect, it is possible to ensure the rigidity of the side wall 33 while ensuring favorable circulation of clutch oil.

[0054] In the clutch device 10 of this embodiment, the fourth groove portion 39 is recessed from the radially inner side toward the radially outer side. According to the above aspect, the clutch oil inside the clutch housing 30 can be collected in the fourth groove portion 39 and then discharged to the outside of the clutch housing 30, so that a larger amount of clutch oil can be discharged to the outside of the clutch housing 30 via the fourth groove portion 39.

[0055] In the clutch device 10 of this embodiment, when the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 36D2 of the first groove 36 in the second direction D2 is L1, the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 37D2 of the second groove 37 in the second direction D2 is L2, the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 38D2 of the third groove 38 in the second direction D2 is L3, and the length from the end 33D1 of the side wall 33 in the first direction D1 to the end 39D2 of the fourth groove 39 in the second direction D2 is L4, the relationship L1 > L4 > L3 > L2 is satisfied. According to the above aspect, it is possible to achieve a reduction in the weight of the clutch housing 30 while holding a plurality of input side rotating plates 20 in the clutch housing 30.

[0056] In the clutch device 10 of this embodiment, the clutch housing 30 is provided with a step portion 34 that is provided between the second groove portion 37 and the third groove portion 38 and that is able to come into contact with a part of the outermost input side rotating plate 20X. According to the above aspect, the outermost input side rotating plate 20X can be more reliably held in the second groove portion 37.

[0057] In the clutch device 10 of this embodiment, at least a portion of the second groove portion 37 (here, the entire second groove portion 37) penetrates in the radial direction. According to the above aspect, a further weight reduction of the clutch housing 30 is achieved. Furthermore, because the second groove portion 37 also penetrates in the radial direction, clutch oil circulates more smoothly between the inside and outside of the clutch housing 30.

[0058] Second Embodiment 11 is a perspective view of a clutch housing 130 according to the second embodiment. The clutch device 10 according to the second embodiment is similar to the clutch device 10 according to the first embodiment except that the clutch housing 130 is provided instead of the clutch housing 30.

[0059] The clutch housing 130 is made of an aluminum alloy. The clutch housing 130 is formed in a cylindrical shape with a bottom. As shown in FIG. 11, the clutch housing 130 has a ring-shaped bottom wall 131, a side wall 133 extending in a first direction D1 from the outer periphery of the bottom wall 131, and an annular wall 140. The clutch housing 130 holds a plurality of input side rotating plates 20 (see FIG. 2).

[0060] As shown in FIGS. 11 and 12 , the annular wall 140 is provided on the outer side of the side wall 133 in the radial direction of the output shaft 15. The annular wall 140 is continuous over the entire circumferential direction S. The outer peripheral surface of the annular wall 140 is located on the same circle centered on the axis of the output shaft 15 and is formed as a smooth surface over the entire circumferential direction S. At least a portion of the annular wall 140 is located radially outward of an end 133D1 of the side wall 133 in the first direction D1. The annular wall 140 is provided from a portion of a second groove portion 137 to a portion of a third groove portion 138, which will be described later. As shown in FIG. 14 , the annular wall 140 overlaps a portion of the second groove portion 137 and a portion of the third groove portion 138, as viewed in the radial direction. The ... step portion 134, which will be described later, as viewed in the radial direction.

[0061] As shown in FIGS. 11 and 12, the clutch housing 130 has a first groove 136. The first groove 136 is provided in the side wall 133. As shown in FIG. 13, the first groove 136 is recessed in the second direction D2 from an end 133D1 of the side wall 133 in the first direction D1. A portion of the first groove 136 penetrates the side wall 133 in the radial direction. In this embodiment, a portion of the first groove 136 that is closer to the second direction D2 than the annular wall 140 penetrates the side wall 133 in the radial direction. The multiple first grooves 136 are provided at equal intervals in the circumferential direction S. The first grooves 136 hold multiple input side rotating plates 20. The claws 20B (see FIG. 2) of the input side rotating plate 20 engage with the first grooves 136.

[0062] As shown in FIGS. 11 and 12 , the clutch housing 130 has second groove portions 137. The second groove portions 137 are provided in the side wall 133. The second groove portions 137 are adjacent to the first groove portions 136 in the circumferential direction S. As shown in FIG. 14 , the second groove portions 137 are provided alternately with the first groove portions 136 in the circumferential direction S. The second groove portions 137 are recessed in the second direction D2 from an end portion 133D1 of the side wall 133 in the first direction D1. A portion of the second groove portion 137 penetrates the side wall 133 in the radial direction. In this embodiment, a portion of the second groove portion 137 closer to the first direction D1 than the annular wall 140 penetrates in the radial direction. The plurality of second groove portions 137 are provided at equal intervals in the circumferential direction S. The second groove portion 137 holds the outermost input side rotating plate 20X (see FIG. 1) that is located furthest in the first direction D1 among the multiple input side rotating plates 20. The second groove portion 137 holds only the outermost input side rotating plate 20X among the multiple input side rotating plates 20. The claw portion 20B of the outermost input side rotating plate 20X engages with the second groove portion 137. Note that the outermost input side rotating plate 20X does not engage with the first groove portion 136.

[0063] As shown in FIGS. 11 and 12 , the clutch housing 130 includes a third groove portion 138. The third groove portion 138 is provided in the side wall 133. The third groove portion 138 is adjacent to the first groove portion 136 in the circumferential direction S. As shown in FIG. 14 , the third groove portion 138 is recessed in the second direction D2 from the end of the second groove portion 137 in the second direction D2. The third groove portion 138 is continuous with the second groove portion 137. A portion of the third groove portion 138 penetrates the side wall 133 in the radial direction. In this embodiment, a portion of the third groove portion 138 that is closer to the second direction D2 than the annular wall 140 penetrates the radial direction. The multiple third groove portions 138 are provided at equal intervals in the circumferential direction S. The multiple input side rotating plates 20 and the outermost input side rotating plate 20X are not held by the third groove portion 138. The claw portion 20B of the input side rotating plate 20 does not engage with the third groove portion 138.

[0064] 14, the clutch housing 130 has a step portion 134 provided between the second groove portion 137 and the third groove portion 138. The step portion 134 is provided so as to be able to come into contact with a part of the outermost input side rotating plate 20X.

[0065] As shown in Figures 11 and 12, the clutch housing 130 has a cutout portion 145. The cutout portion 145 is provided in the annular wall 140. As shown in Figure 15, the cutout portion 145 is recessed in the second direction from an end portion 140D1 of the annular wall 140 in the first direction D1. At least a portion of the cutout portion 145 penetrates the side wall 133 in the radial direction. The cutout portion 145 is located between adjacent first groove portions 136 in the circumferential direction S. The cutout portion 145 is located radially outward of the second groove portion 137. The cutout portion 145 overlaps a portion of the second groove portion 137 when viewed radially. The cutout portion 145 communicates with the second groove portion 137. The length H1 in the direction D of the portion of the annular wall 140 where the cutout portion 145 is formed is equal to or less than half the length H2 in the direction D of the annular wall 140. As shown in Fig. 14 , the length H2 in the direction D of the annular wall 140 is longer than the length H3 from the end 133D1 in the first direction D1 of the side wall 133 to the end 137D2 in the second direction D2 of the second groove portion 137.

[0066] As shown in FIGS. 13 and 14 , the length K1 in the circumferential direction S of the first groove portion 136 is longer than the length K2 in the circumferential direction S of the second groove portion 137. The length K2 in the circumferential direction S of the second groove portion 137 is longer than the length K3 in the circumferential direction S of the third groove portion 138. The length M in the circumferential direction S of the cutout portion 145 is longer than the length K2 in the circumferential direction S of the second groove portion 137. The length M in the circumferential direction S of the cutout portion 145 is longer than the length K1 in the circumferential direction S of the first groove portion 136. In this embodiment, the lengths K1 and K2 are longer than the length P5 in the circumferential direction S of the claw portion 20B of the input-side rotating plate 20 (see FIG. 2 ). The length K3 is shorter than the length P5. As a result, the claw portion 20B can fit into the first groove portion 136 and the second groove portion 137, but cannot fit into the third groove portion 138.

[0067] In the clutch device 10 of this embodiment, the clutch housing 130 includes an annular wall 140 that is provided radially outward of the side wall 133 and that is continuous over the entire circumferential direction S. According to the above aspect, the rigidity of the clutch housing 130 can be increased.

[0068] In the clutch device 10 of this embodiment, the annular wall 140 is provided from a part of the second groove portion 137 to a part of the third groove portion 138. According to the above aspect, even when the third groove portion 138 is provided, the rigidity of the side wall 133 can be increased.

[0069] 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.

[0070] In the above-described embodiments, the clutch center 40 and the pressure plate 70 are each configured to hold the output side rotating plate 22, but this is not limiting. For example, only the clutch center 40 may be configured to hold the output side rotating plate 22, or only the pressure plate 70 may be configured to hold the output side rotating plate 22.

[0071] In each of the above-described embodiments, the center side cam portion 60 has a center side assist cam surface 60A and a center side slipper cam surface 60S, but it may have only one of them or neither.

[0072] In each of the above-described embodiments, the pressure side cam portion 90 has a pressure side assist cam surface 90A and a pressure side slipper cam surface 90S, but it may have only one of them or neither.

[0073] In the above-described embodiments, the second groove 37 and the second groove 137 are configured to hold only the outermost input side rotating plate 20X among the multiple input side rotating plates 20, but this is not limiting. The second groove 37 and the second groove 137 may be configured to hold at least one more input side rotating plate 20 in addition to the outermost input side rotating plate 20X. In this case, the step portion 34 and the step portion 134 are provided so that they can come into contact with a portion of the input side rotating plate 20.

[0074] In the second embodiment described above, the cutout portions 145 are located between adjacent first groove portions 136 in the circumferential direction S and radially outward from the second groove portions 137. However, this is not limiting. The cutout portions 145 may be located between adjacent second groove portions 137 in the circumferential direction S and radially outward from the first groove portions 136. The cutout portions 145 may overlap with portions of the first groove portions 136 when viewed from the radial direction. The cutout portions 145 may be in communication with the first groove portions 136. In this case, the length M of the cutout portions 145 in the circumferential direction S is longer than the length K1 of the first groove portions 136 in the circumferential direction. The second groove portions 137 do not have to penetrate the side wall 133 in the radial direction. The cutout portions 145 may be located radially inward from the first groove portions 136 or the second groove portions 137.

[0075] In the second embodiment described above, the annular wall 140 is provided across a portion of the second groove portion 137 and a portion of the third groove portion 138, and is configured to overlap a portion of the second groove portion 137 and a portion of the third groove portion 138 when viewed from the radial direction, but this is not limiting. The annular wall 140 may be configured to overlap only with at least a portion of the second groove portion 137 when viewed from the radial direction, or may be configured to overlap only with at least a portion of the third groove portion 138 when viewed from the radial direction.

[0076] The technology disclosed herein can be applied to various types of clutch devices. In the above-described embodiment, a so-called external disengagement type clutch device in which the pressure plate 70 is located between the clutch center 40 and the clutch housing 30 in the axial direction of the output shaft 15 has been described as an example, but the present invention is not limited to this. For example, the technology disclosed herein can be similarly applied to a so-called internal disengagement type clutch device in which the pressure plate 70 is located on the opposite side of the clutch center 40 from the clutch housing 30 in the axial direction of the output shaft 15. [Explanation of symbols]

[0077] 10 Clutch device 15 Output shaft 20 Input side rotating plate 20X Outermost input side rotating plate 22 Output side rotating plate 30 Clutch housing 31 Bottom wall 33 Side wall 33D1 End in the first direction D1 34 Step 35 input gear 36 First groove 37 Second groove 38 Third groove 39 Fourth groove 40 Clutch center 70 Pressure Plate 100 lifter plate

Claims

1. A clutch device that transmits or cuts off the rotational driving force of an input shaft to an output shaft, a gear that is rotationally driven by the rotational drive of the input shaft; a clutch housing that rotates integrally with the gear and holds a plurality of input side rotary plates; a clutch center accommodated in the clutch housing and rotatably 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 able to rotate relatively thereto, and that is able to press the input side rotating plate and a plurality of output side rotating plates that are arranged alternately with the input side rotating plate, The clutch housing is a ring-shaped bottom wall to which the gear is attached; a side wall extending from an outer peripheral edge of the bottom wall in a first direction, where a direction from one side to the other side in an axial direction of the output shaft is defined as a first direction and a direction from the other side to the one side is defined as a second direction; a first groove portion provided on the side wall, recessed in the second direction from an end of the side wall in the first direction, at least a portion of which penetrates in a radial direction, and which holds the plurality of input side rotating plates; a second groove portion provided in the side wall, adjacent to the first groove portion in the circumferential direction, recessed in the second direction from an end of the side wall in the first direction, and configured to hold at least an outermost input side rotating plate located furthest to the first direction side among the plurality of input side rotating plates; a third groove portion provided on the side wall, recessed in the second direction from the second direction end of the second groove portion, at least a portion of which penetrates in the radial direction, and which does not hold the input side rotating plate or the outermost input side rotating plate.

2. 2. The clutch device according to claim 1, wherein the clutch housing has a fourth groove portion provided on the side wall and at least a portion of which is recessed in the second direction and the radial direction from the end of the third groove portion in the second direction.

3. The clutch device according to claim 2 , wherein the length of the third groove portion in the circumferential direction is shorter than the length of the second groove portion in the circumferential direction.

4. The clutch device according to claim 3 , wherein the third groove portion has a length in the circumferential direction that is shorter than the length in the circumferential direction of the fourth groove portion.

5. 3. The clutch device according to claim 2, wherein the circumferential length of the second groove portion, the circumferential length of the third groove portion, and the circumferential length of the fourth groove portion are shorter than the circumferential length of the first groove portion.

6. The clutch device according to claim 2 , wherein the fourth groove portion is recessed from the radially inner side toward the radially outer side.

7. 3. The clutch device according to claim 2, wherein the relationship L1 > L4 > L3 > L2 is satisfied, where L1 is the length from the end of the side wall in the first direction to the end of the first groove portion in the second direction, L2 is the length from the end of the side wall in the first direction to the end of the second groove portion in the second direction, L3 is the length from the end of the side wall in the first direction to the end of the third groove portion in the second direction, and L4 is the length from the end of the side wall in the first direction to the end of the fourth groove portion in the second direction.

8. 4. The clutch device according to claim 3, wherein the clutch housing is provided between the second groove portion and the third groove portion and has a stepped portion with which a part of the outermost input side rotating plate can come into contact.

9. 2. The clutch device according to claim 1, wherein the clutch housing includes an annular wall that is provided radially outward of the side wall and that is continuous over the entire circumferential direction.

10. The clutch device according to claim 9, wherein the annular wall is provided across from a portion of the second groove portion to a portion of the third groove portion.

11. The clutch device according to claim 10, wherein the length of the third groove portion in the circumferential direction is shorter than the length of the second groove portion in the circumferential direction.

12. The clutch device according to claim 1 , wherein at least a portion of the second groove portion penetrates in the radial direction.

Images