Clutch device

Abstract

To supply a clutch oil circulating in an insertion hole, to a member positioned at a radial outer side with respect to an output shaft holding portion to which an output shaft is connected.SOLUTION: A clutch device includes: a clutch center 40 rotated and driven with an output shaft 15; and a pressure plate 70 disposed so as to be able to approach or separate from the clutch center 40 and relatively rotate thereto. The clutch center 40 includes an output shaft holding portion 42 to which the output shaft 15 is connected, and the output shaft holding portion 42 includes an insertion hole 45 to which the output shaft 15 is inserted. On an end face 42D1 in a first direction D1 of the output shaft holding portion 42, an oil groove 42P is formed which is communicated with the insertion hole 45 and extending to an outer edge 42DO in a radial direction of the output shaft 15 and in a radial direction of the end face 42D1 in the first direction D1 from the insertion hole 45, so as to allow clutch oil flowing out of the output shaft 15 to flow therein.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] A straddle-type vehicle such as a motorcycle is provided with a clutch device capable of transmitting and interrupting the rotational driving force of a power source such as an engine to a driving wheel. For example, Patent Document 1 discloses a clutch device having an input member (hereinafter referred to as input shaft) connected to the engine side, an output member (hereinafter referred to as output shaft) connected to the driving wheel side, a clutch member (hereinafter referred to as clutch center) connected to the output shaft, and a pressure member (hereinafter referred to as pressure plate) capable of approaching or separating from the clutch center. Here, the clutch center is fixed to the output shaft in order to transmit the rotational driving force input from the input shaft to the output shaft. The clutch center has an output shaft holding portion to which the output shaft is connected, and an insertion hole into which the output shaft is inserted is formed in the output shaft holding portion. In addition, clutch oil flows inside the output shaft, and the clutch oil flows to the outside from a predetermined portion of the output shaft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-030211 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, a member such as a washer or an auxiliary clutch plate may be disposed on the end face of the output shaft holding portion of the clutch center opposite the side on which the pressure plate is disposed. For this reason, this end face is often machined to be flat. However, because the flattened end face and a member such as a washer come into close contact with each other, there is a problem in that the clutch oil circulating inside the output shaft cannot be sufficiently supplied to the member located radially outward of the output shaft holding portion.

[0005] The present invention has been made in consideration of these points, and its object is to provide a clutch device that can supply clutch oil circulating within the output shaft to a member located radially outward from the output shaft holding portion. [Means for solving the problem]

[0006] 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 housed 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, and a pressure plate that is arranged 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, The clutch oil flowing out from the output shaft flows through an oil groove formed on an end face of the output shaft holding portion in the first direction, the oil groove communicating with the insertion hole and extending in the radial direction of the output shaft and from the insertion hole to the radial outer edge of the end face in the first direction, 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.

[0007] In the clutch device according to the present invention, the oil groove formed on the end face in the first direction of the output shaft holding part communicates with the insertion hole and extends in the radial direction of the output shaft and from the insertion hole to the radial outer edge of the end face in the first direction. Therefore, even if a member such as a washer is arranged on the end face in the first direction of the output shaft holding part, the clutch oil that flows out from the output shaft via the oil groove can be supplied to the outside (for example, the input side rotating plate or the output side rotating plate) from the radial outer edge of the end face in the first direction of the output shaft holding part. Effect of the Invention

[0008] According to the present invention, it is possible to provide a clutch device that can supply clutch oil circulating inside the output shaft to a member located radially outward from the output shaft holding portion. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of a clutch device according to one embodiment. [Diagram 2] FIG. 2 is an enlarged cross-sectional view of a portion of the clutch device according to one embodiment. [Diagram 3] FIG. 3 is a perspective view of the first clutch center according to one embodiment. [Figure 4] FIG. 4 is a perspective view of the first clutch center according to one embodiment. [Diagram 5] FIG. 5 is a plan view of the first clutch center according to one embodiment. [Figure 6] FIG. 6 is a bottom view of the first clutch center according to one embodiment. [Figure 7] FIG. 7 is a perspective view of the second clutch center according to one embodiment. [Figure 8] FIG. 8 is a plan view of the second clutch center according to one embodiment. [Figure 9] FIG. 9 is a perspective view of a pressure plate according to one embodiment. [Figure 10] FIG. 10 is a plan view of a pressure plate according to one embodiment. [Figure 11] FIG. 11 is a cross-sectional view of a centrifugal clutch mechanism according to one embodiment. [Figure 12] FIG. 12 is a partially cutaway perspective view of a centrifugal clutch mechanism according to one embodiment. [Figure 13] FIG. 13 is a perspective view of an auxiliary clutch plate according to one embodiment. [Figure 14] FIG. 14 is a perspective view of an auxiliary clutch plate according to one embodiment. [Figure 15A]FIG. 15A is a schematic diagram for explaining the action of the center side assist cam surface and the pressure side assist cam surface. [Figure 15B] FIG. 15B is a schematic diagram for explaining the action of the center-side slipper cam surface and the pressure-side slipper cam surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] 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.

[0011] 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.

[0012] 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 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. The circumferential direction of the clutch center 40 and the pressure plate 70 is referred to as a circumferential direction S, the direction from one pressure side cam portion 90 to the other pressure side cam portion 90 in relation to the circumferential direction S (the direction from one center side cam portion 60 to the other center side cam portion 60) is referred to as a first circumferential direction S1 (see FIG. 3), and the direction from the other pressure side cam portion 90 to one pressure side cam portion 90 (the direction from the other center side cam portion 60 to one center side cam portion 60) is referred to as a second circumferential direction S2 (see FIG. 3). 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 a 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 direction is merely a direction defined for the convenience of explanation, and does not limit the installation mode of the clutch device 10 or the present invention in any way.

[0013] 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, a centrifugal clutch mechanism 120, and an auxiliary clutch plate 150.

[0014] As shown in Fig. 1, the output shaft 15 is a shaft body formed in 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 28A. The output shaft 15 fixedly supports a clutch center 40 via a nut 28B. 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.

[0015] As shown in FIG. 1, the output shaft 15 includes a main body 15A extending in the direction D and a communication hole 15B formed in the main body 15A. The main body 15A has an oil passage 15H through which clutch oil flows. The oil passage 15H is formed between the main body 15A and a sleeve 16C fitted onto a push rod 16A (described later). The clutch oil flows through the output shaft 15, i.e., through the oil passage 15H of the main body 15A. The communication hole 15B extends in the radial direction of the output shaft 15 (hereinafter, referred to as the radial direction. The radial direction is a direction perpendicular to the direction D). The communication hole 15B communicates with the oil passage 15H. A part of the clutch oil flowing through the oil passage 15H flows into the communication hole 15B. For example, one or two communication holes 15B are formed in the main body 15A. As shown in FIG. 2, at least a portion of the communicating hole 15B is located, with respect to the axial direction (i.e., direction D) of the output shaft 15, between an end face 42D1 in the first direction D1 of the output shaft holding portion 42 described later and an end face 47D1 in the first direction D1 of the mating tooth 47 described later.

[0016] As shown in FIG. 1, the oil passage 15H of the output shaft 15 is provided with a push rod 16A and a push member 16B provided adjacent to the push rod 16A. The push rod 16A and the push member 16B are provided slidably in a sleeve 16C. One end (the end on the left side in the figure) of the push rod 16A is connected to a clutch operation lever (not shown) of the motorcycle, and the push rod 16A slides in the sleeve 16C and presses the push member 16B in the second direction D2 by operating the clutch operation lever. A part of the push member 16B protrudes outward from the output shaft 15 (in this case, the second direction D2) and is connected to a release bearing 18 provided on the pressure plate 70. The sleeve 16C and the push member 16B are formed to be narrower than the inner diameter of the main body 15A, and the flow of clutch oil is ensured in the oil passage 15H.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] The input side rotating plate 20 is a member pressed against the output side rotating plate 22. The input side rotating plate 20 is a flat plate formed in an annular shape. The input side rotating plate 20 is formed by casting an aluminum alloy. Friction materials (not shown) made of multiple pieces of paper are attached to the front and back surfaces of the input side rotating plate 20. Grooves several μm to several tens of μm deep are formed between the friction materials to hold clutch oil.

[0021] 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 holds an 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. The clutch center 40 includes a first clutch center 41 and a second clutch center 51. The first clutch center 41 and the second clutch center 51 are assembled to each other. The second clutch center 51 is located radially outside the first clutch center 41. The second clutch center 51 is fitted onto the first clutch center 41.

[0022] As shown in FIG. 3, the first clutch center 41 includes an output shaft holding portion 42, an annular base wall 43 located radially outward of the output shaft holding portion 42, and a plurality of center side cam portions 60.

[0023] As shown in FIG. 1, the output shaft 15 is connected to the output shaft holding portion 42. As shown in FIG. 3, the output shaft holding portion 42 is formed in a cylindrical shape. The output shaft holding portion 42 is formed with an insertion hole 45 into which the output shaft 15 is inserted and spline-fitted. The insertion hole 45 is formed penetrating the output shaft holding portion 42. An inner wall 45A of the output shaft holding portion 42 that defines the insertion hole 45 is formed with a plurality of fitting teeth 47 extending in the axial direction of the output shaft 15 (i.e., direction D). The fitting teeth 47 fit with the output shaft 15.

[0024] As shown in FIG. 4, an oil groove 42P through which clutch oil flows is formed on an end face 42D1 of the output shaft holding portion 42 in the first direction D1. The oil groove 42P extends in the radial direction of the output shaft 15. The oil groove 42P communicates with the insertion hole 45. The oil groove 42P extends from the insertion hole 45 to the radial outer edge 42DO of the end face 42D1 in the first direction D1. The oil groove 42P is recessed from the end face 42D1 in the second direction D2. Here, two oil grooves 42P are formed on the end face 42D1, but the number of oil grooves 42P is not limited to two. The two oil grooves 42P are provided at positions facing each other. As shown in FIG. 2, the oil groove 42P is located on the radial outer side of the communication hole 15B of the output shaft 15.

[0025] As shown in FIG. 4, at least a part of an end face 42D1 in the first direction D1 of the output shaft holding portion 42 is located closer to the first direction D1 than an end face 47D1 in the first direction D1 of the fitting tooth 47. Here, the entire end face 42D1 is located closer to the first direction D1 than the end face 47D1. A step portion 48 is formed between the end face 42D1 in the first direction D1 of the output shaft holding portion 42 and the end face 47D1 in the first direction D1 of the fitting tooth 47. In this embodiment, the step portion 48 is formed around the entire circumference of the output shaft holding portion 42 (around the entire circumference of the insertion hole 45). Clutch oil is temporarily held in the step portion 48. As shown in Figure 6, when viewed from the axial direction of the output shaft 15, the diameter R1 of the portion of the insertion hole 45 defined by the inner edge 42I of the end face 42D1 of the output shaft holding portion 42 in the first direction D1 is larger than the diameter R2 of the portion of the insertion hole 45 defined by the radially inner edge portion 47I of the mating tooth 47 (a virtual circle passing through the edge portion 47I).

[0026] 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 (pressing force) between the input side rotating plate 20 and the output side rotating plate 22, or a slipper torque, which is a force that reduces the pressing force (pressing force) between the input side rotating plate 20 and the output side rotating plate 22 and shifts to a half-clutch state. As shown in FIG. 3, the center cam portion 60 is formed so as to protrude in the second direction D2 from a surface 43D2 on the second direction D2 side of the base wall 43. As shown in FIG. 5, the center cam portions 60 are disposed at equal intervals in the circumferential direction S of the first clutch center 41. In this embodiment, the first clutch center 41 has three center cam portions 60, but the number of center cam portions 60 is not limited to three.

[0027] As shown in FIG. 3, the center-side cam portion 60 is located radially outward of the output shaft holding portion 42. The center-side cam portion 60 has a center-side assist cam surface 60A (see also FIG. 6) 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 rotating 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.

[0028] As shown in FIG. 3, the first clutch center 41 has a plurality of boss portions 62 (three in this embodiment). The boss portions 62 are members for fixing the pressure plate 70. The plurality of boss portions 62 are disposed at equal intervals in the circumferential direction S. The boss portions 62 are formed in a cylindrical shape. The boss portions 62 are positioned radially outward from the output shaft holding portion 42. The boss portions 62 extend toward the pressure plate 70 (i.e., toward the second direction D2). The boss portions 62 are provided on the center-side cam portion 60. The boss portions 62 are provided between the center-side assist cam surface 60A and the center-side slipper cam surface 60S with respect to the circumferential direction S. The boss portions 62 are formed with a screw hole 62H into which the bolt 28 (see FIG. 1) is inserted. The screw hole 62H extends in the axial direction of the clutch center 40 (i.e., in the direction D).

[0029] As shown in Fig. 5, the first clutch center 41 has a center-side cam hole 43H that penetrates 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 is located between adjacent center-side cam portions 60 in the circumferential direction S. As shown in Fig. 6, 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.

[0030] 3, the first clutch center 41 has a plurality of engagement grooves 49. The engagement grooves 49 are formed in the outer circumferential surface of the base wall 43. The engagement grooves 49 are recessed from the outer circumferential surface of the base wall 43 toward the inside in the radial direction.

[0031] 7, the second clutch center 51 includes an annular outer peripheral wall 52, a flange 68 extending radially outward from the outer peripheral wall 52, and a center-side fitting portion 54. The second clutch center 51 holds an input side rotating plate 20 and a plurality of output side rotating plates 22 arranged alternately in direction D.

[0032] As shown in FIG. 7, a spline fitting portion 56 is provided on the outer peripheral surface of the outer peripheral wall 52. The spline fitting portion 56 has a plurality of center side fitting teeth 57 extending in the axial direction of the second clutch center 51 (i.e., direction D) along the outer peripheral surface of the outer peripheral wall 52, a plurality of spline grooves 58 formed between adjacent center side fitting teeth 57 and extending in the axial direction of the second clutch center 51 (i.e., direction D), and an oil discharge hole 59. The center side fitting teeth 57 hold the output side rotating plate 22. The center side fitting teeth 57 are arranged in the circumferential direction S. The center side fitting teeth 57 are formed at equal intervals in the circumferential direction S. The center side fitting teeth 57 are formed in the same shape. The center side fitting teeth 57 protrude radially outward from the outer peripheral surface of the outer peripheral wall 52. The oil discharge hole 59 is formed penetrating the outer peripheral wall 52 in the radial direction. The oil discharge hole 59 is formed between adjacent center side fitting teeth 57. That is, the oil discharge hole 59 is formed in the spline groove 58. The oil discharge hole 59 is formed in the center side fitting portion 54. The oil discharge hole 59 communicates between the inside and the outside of the second clutch center 51. The oil discharge hole 59 is a hole that discharges clutch oil and the like that has flowed out from the output shaft 15 into the clutch center 40 to the outside of the clutch center 40. The clutch oil discharged from the oil discharge hole 59 is supplied to the input side rotating plate 20 and the output side rotating plate 22 that are located radially outside the oil discharge hole 59.

[0033] The output side rotating plate 22 is held by the spline fitting portion 56 of the second clutch center 51 and the pressure plate 70. A part of the output side rotating plate 22 is held by the center side fitting teeth 57 and the spline grooves 58 of the second clutch center 51 through spline fitting. Another part of the output side rotating plate 22 is held by pressure side fitting teeth 77 (see FIG. 9 ) 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.

[0034] 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 casting an aluminum alloy. 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.

[0035] As shown in Fig. 7, the center-side fitting portion 54 is formed on the inner peripheral surface of the outer peripheral wall 52. The center-side fitting portion 54 is configured to be slidably fitted onto a pressure-side fitting portion 88 (see Fig. 9) described later. The inner diameter of the center-side fitting portion 54 is formed with a fitting tolerance that allows the flow of clutch oil flowing out from the tip end 15T (see Fig. 1) of the output shaft 15 relative to the pressure-side fitting portion 88. That is, a gap is formed between the center-side fitting portion 54 and the pressure-side fitting portion 88.

[0036] 7 and 8, the second clutch center 51 has a plurality of engagement protrusions 55. The engagement protrusions 55 engage with the engagement grooves 49 (see FIG. 3) of the first clutch center 41. The engagement protrusions 55 are formed on the inner circumferential surface of the outer circumferential wall 52. The engagement protrusions 55 protrude radially inward from the inner circumferential surface of the outer circumferential wall 52. The engagement protrusions 55 are located on the first direction D1 side with respect to the oil discharge hole 59.

[0037] As shown in FIG. 1, the pressure plate 70 is provided so as to be capable of approaching or separating from the clutch center 40 and rotatable relative thereto. The pressure plate 70 is configured so as to be capable of pressing 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. As shown in FIG. 9, 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 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 flange 98 is located radially outward beyond a cylindrical portion 80 described later. 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 flange 98 is configured so as to be capable of pressing the input side rotating plate 20 and the output side rotating plate 22.

[0038] As shown in FIG. 9, 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 FIG. 1).

[0039] As shown in Fig. 9, the tubular portion 80 is formed in a cylindrical shape. The tubular portion 80 is formed integrally with the pressure-side cam portion 90. The tubular portion 80 accommodates the tip portion 15T (see Fig. 1) of the output shaft 15. The tubular portion 80 accommodates the release bearing 18 (see Fig. 1). The tubular portion 80 is a portion that receives a pressing force from the push member 16B (see Fig. 1) via the release bearing 18. The tubular portion 80 is a portion that receives the clutch oil that flows out from the tip portion 15T of the output shaft 15.

[0040] 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. As shown in FIG. 9, 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. 10, 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.

[0041] As shown in FIG. 10, 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. 9) 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.

[0042] 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. 15A. 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 between the input side rotating plate 20 and the output side rotating plate 22.

[0043] 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. 15B. 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 pressure contact 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 transmission due to back torque.

[0044] 10, 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 on the second direction D2 side 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 54 (see FIG. 7).

[0045] As shown in FIG. 9 and FIG. 10, 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 between the pressure side assist cam surface 90A and the pressure side slipper cam surface 90S of the adjacent pressure side cam portion 90. As shown in FIG. 10, 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. The boss portion 62 (see FIG. 3) of the first clutch center 41 is inserted into the pressure side cam hole 73H.

[0046] As shown in FIG. 9, the pressure plate 70 has a plurality of pressure-side fitting teeth 77 arranged on a flange 98. The pressure-side fitting teeth 77 hold the output-side rotating plate 22. The pressure-side fitting teeth 77 protrude from the flange 98 in a first direction D1. 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 pressure-side fitting teeth 77 are aligned in the circumferential direction S. The pressure-side fitting teeth 77 are arranged at equal intervals in the circumferential direction S. In this embodiment, some of the pressure-side fitting teeth 77 are removed, so the intervals between the removed portions are wider, but the remaining adjacent pressure-side fitting teeth 77 are arranged at equal intervals.

[0047] As shown in Fig. 1, 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 (see also Fig. 15A). The spring accommodating portion 84 is formed in a circular shape. The spring accommodating portion 84 accommodates the pressure spring 25.

[0048] 1, the pressure spring 25 is accommodated in 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 in which spring steel is wound in a spiral shape.

[0049] As shown in FIG. 1, the centrifugal clutch mechanism 120 is provided in the clutch housing 30. The centrifugal clutch mechanism 120 is provided on the first direction D1 side of the clutch center 40. The centrifugal clutch mechanism 120 is located radially outside the oil groove 42P. The centrifugal clutch mechanism 120 is located on an extension line 42PL (see also FIG. 2) of the oil groove 42P. The centrifugal clutch mechanism 120 is held by the clutch housing 30. The centrifugal clutch mechanism 120 is provided so as to be rotatable integrally with the clutch housing 30. As shown in FIG. 11 and FIG. 12, the centrifugal clutch mechanism 120 has a weight member 122, a holding member 124, a pressing member 126, a support member 128, a first spherical member 131, a second spherical member 132, and a biasing member 135 (see FIG. 1). When the weight member 122 is located at the radially outer position, the centrifugal clutch mechanism 120 presses the input side rotating plate 20 and the output side rotating plate 22 together to enable transmission of the rotational driving force of the input shaft to the output shaft 15. When the weight member 122 is located at the radially inner position, the centrifugal clutch mechanism 120 releases the pressing force between the input side rotating plate 20 and the output side rotating plate 22 to enable interruption of transmission of the rotational driving force of the input shaft to the output shaft 15. The centrifugal clutch mechanism 120 is configured to be able to press a disk portion 154 (see FIG. 13), described later, of the auxiliary clutch plate 150 (see FIG. 13).

[0050] The weight member 122 is configured to be movable from a radially inner position to a radially outer position by centrifugal force accompanying rotation of the clutch housing 30. As shown in Fig. 11, the weight member 122 is accommodated in an accommodating portion 124A (described later) of the holding member 124. The weight member 122 is held at a radially inner position when no centrifugal force is applied. When centrifugal force is applied, the weight member 122 moves radially outward against the biasing force of a biasing member 135 (see Fig. 1) and moves to a radially outer position.

[0051] As shown in FIG. 11, the holding member 124 holds the weight member 122 movably between a radially inner position and a radially outer position. The holding member 124 is formed in an annular shape. The holding member 124 has a plurality of accommodating portions 124A formed in the circumferential direction, a gradient groove 124B formed in the accommodating portion 124A, and a pressing surface 124C. The accommodating portion 124A accommodates the weight member 122. The accommodating portion 124A is formed in a concave shape that matches the shape and movement range of the weight member 122. An outer peripheral wall surface 124AA of the accommodating portion 124A is configured so that one end of the biasing member 135 (see FIG. 1) can abut against it.

[0052] As shown in FIG. 11 and FIG. 12, the pressing member 126 is configured to be able to press the input side rotating plate 20 and the output side rotating plate 22 by moving in the second direction D2 as the weight member 122 moves from a radially inner position to an outer position. The pressing member 126 is formed in an annular shape. The pressing member 126 has a plurality of gradient grooves 126A formed in the circumferential direction, grooves 126B formed at the positions where the gradient grooves 126A are formed, and a pressing surface 126C. The gradient grooves 126A are formed at positions corresponding to the weight members 122. The gradient grooves 126A are inclined so as to face the first direction D1 from the radially inner side toward the radially outer side. When the clutch housing 30 is stopped, the weight member 122 is held radially inner by the biasing force of the biasing member 135 (see FIG. 1). When the clutch housing 30 rotates and centrifugal force is applied to the weight member 122, the weight member 122 moves along the inclined groove 126A, and the pressing member 126 moves in a direction away from the holding member 124 (i.e., the second direction D2). As a result, the pressing surface 126C of the pressing member 126 presses the flange 68 (see FIG. 1) of the second clutch center 51 in the second direction D2. The holding member 124 and the pressing member 126 have a plurality of protrusions 127 formed in the circumferential direction. The holding member 124 and the pressing member 126 are held by the inner circumferential surface of the side wall 33 of the clutch housing 30 via the protrusions 127, similar to the input side rotating plate 20. The holding member 124 and the pressing member 126 are held by fitting into the clutch housing 30. The holding member 124 and the pressing member 126 are provided so as to be displaceable along the axial direction (that is, direction D) of the clutch housing 30. The holding member 124 and the pressing member 126 are provided so as to be rotatable integrally with the clutch housing 30.

[0053] As shown in Fig. 11 and Fig. 12, the support member 128 is attached to the holding member 124. The support member 128 is fixed to a surface of the holding member 124 on the second direction D2 side. The support member 128 holds the weight member 122 so that the weight member 122 is movable in the radial direction. As shown in Fig. 2, a friction material 175 is provided between the support member 128 and the clutch center 40 (here, the first clutch center 41). The friction material 175 is an example of another friction material.

[0054] As shown in Figs. 11 and 12, the first spherical member 131 is attached to the weight member 122. The first spherical member 131 is, for example, a steel ball. The first spherical member 131 protrudes partially from one opening of a through hole formed in the weight member 122 and contacts the gradient groove 126A of the pressure contact member 126. The second spherical member 132 is attached to the weight member 122. The second spherical member 132 is, for example, a steel ball. The second spherical member 132 protrudes partially from the other opening of a through hole formed in the weight member 122 and contacts the gradient groove 124B of the holding member 124.

[0055] 1, the biasing member 135 is disposed radially outward of the weight member 122. The biasing member 135 biases the weight member 122 radially inward. The biasing member 135 is, for example, a coil spring.

[0056] In such a centrifugal clutch mechanism 120, when centrifugal force is not applied to the weight member 122, the weight member 122 is held at a radially inner position, and the pressing force of the input side rotating plate 20 and the output side rotating plate 22 is released. On the other hand, when centrifugal force is applied to the weight member 122, the weight member 122 moves from the radially inner position to the radially outer position. As a result, the pressing surface 126C formed on the pressing member 126 presses the input side rotating plate 20 and the output side rotating plate 22 via the flange 68 of the second clutch center 51 to bring them into a pressed state, and the rotational driving force of the input shaft is capable of being transmitted to the output shaft 15. At this time, the holding member 124 moves in the first direction D1, and the pressing surface 124C formed on the holding member 124 presses the auxiliary clutch plate 150.

[0057] As shown in FIG. 1, the auxiliary clutch plate 150 is provided in the clutch housing 30. The auxiliary clutch plate 150 is fixed to the output shaft 15. The auxiliary clutch plate 150 is disposed on the first direction D1 side of a part of the centrifugal clutch mechanism 120. As shown in FIG. 2, the auxiliary clutch plate 150 is adjacent to an end face 42D1 in the first direction D1 of the output shaft holding part 42 of the first clutch center 41. At least a part of the auxiliary clutch plate 150 and at least a part of the end face 42D1 in the first direction D1 of the output shaft holding part 42 are in surface contact. Note that a member such as a washer may be provided between the auxiliary clutch plate 150 and the end face 42D1.

[0058] The auxiliary clutch plate 150 is configured to be pressed by the centrifugal clutch mechanism 120 (here, the pressing surface 124C of the holding member 124) when the input side rotating plate 20 and the output side rotating plate 22 are pressed against each other (i.e., when the weight member 122 of the centrifugal clutch mechanism 120 is located at the radially outer position) to enable transmission of the rotational driving force of the input shaft to the output shaft 15. The auxiliary clutch plate 150 is configured to be released from the pressing force of the centrifugal clutch mechanism 120 (here, the pressing surface 124C of the holding member 124) when the pressing force between the input side rotating plate 20 and the output side rotating plate 22 is released (i.e., when the weight member 122 is located at the radially inner position) to interrupt transmission of the rotational driving force of the input shaft to the output shaft 15. As shown in FIG. 13, the auxiliary clutch plate 150 has a fitting portion 152 and a disk portion 154. The fitting portion 152 and the disk portion 154 are integrally formed.

[0059] As shown in Fig. 1, the fitting portion 152 fits onto the output shaft 15. The fitting portion 152 is formed with an insertion hole 152H (see also Fig. 13) into which the output shaft 15 is inserted and spline-fitted. The insertion hole 152H is formed penetrating the fitting portion 152. A length L1 of the fitting portion 152 in direction D (i.e., the axial direction of the output shaft 15) is longer than a length L2 of the disk portion 154 in direction D.

[0060] As shown in FIG. 1, the disk portion 154 is located radially outward from the fitting portion 152. The disk portion 154 has an abutment surface 154F which is an end face on the second direction D2 side and is pressed against the centrifugal clutch mechanism 120. As shown in FIG. 2, the abutment surface 154F is pressed against a pressing surface 124C of the holding member 124 of the centrifugal clutch mechanism 120. A friction material 170 (see also FIG. 14) is provided between the abutment surface 154F and the centrifugal clutch mechanism 120. That is, the abutment surface 154F is indirectly pressed against the pressing surface 124C via the friction material 170. The disk portion 154 is located on the second direction D2 side from a center 152C of the fitting portion 152 in the direction D.

[0061] 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 62 of the first clutch center 41 by the bolt 28. The pressure plate 70 is attached by tightening the bolt 28 to the boss portion 62 via the stopper plate 100 with the pressure spring 25 disposed in the spring accommodating portion 84. The stopper plate 100 is formed in a substantially triangular shape in a plan view.

[0062] A predetermined amount of clutch oil is supplied into the clutch device 10. 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. The clutch oil flows through the oil flow path 15H of the output shaft 15 into the clutch center 40 and the pressure plate 70, and is supplied to the input side rotating plate 20 and the output side rotating plate 22. The clutch oil flowing through the oil flow path 15H flows toward the oil groove 42P through the communication hole 15B, as shown by the arrow FL in FIG. 2. Here, a step portion 48 (see also FIG. 4) is formed around the entire circumference of the output shaft holding portion 42 at the end of the output shaft holding portion 42 on the first direction D1 side. Therefore, the clutch oil flows more reliably through the step portion 48 into the oil groove 42P. Furthermore, an end face 42D1 of the output shaft holding portion 42 in the first direction D1 and the auxiliary clutch plate 150 are in surface contact, but since an oil groove 42P is formed in the end face 42D1, the clutch oil flowing out from the communication hole 15B flows through the oil groove 42P to the radial outside of the first clutch center 41. The clutch oil flowing to the radial outside of the first clutch center 41 is supplied to, for example, a friction material 170 provided between the contact surface 154F of the auxiliary clutch plate 150 and the centrifugal clutch mechanism 120, a friction material 175 provided between the support member 128 and the first clutch center 41, the weight member 122 of the centrifugal clutch mechanism 120, the input side rotating plate 20, and the output side rotating plate 22.

[0063] As described above, according to the clutch device 10 of this embodiment, the oil groove 42P formed in the end face 42D1 of the output shaft holding portion 42 in the first direction D1 communicates with the insertion hole 45 and extends in the radial direction of the output shaft 15 from the insertion hole 45 to the radial outer edge 42DO of the end face 42D1 in the first direction D1. For this reason, even if a member such as a washer is disposed on the end face 42D1 of the output shaft holding portion 42 in the first direction D1, the clutch oil flowing out from the output shaft 15 via the oil groove 42P can be supplied to the outside (for example, the input side rotating plate 20 or the output side rotating plate 22) from the radial outer edge 42DO of the end face 42D1 of the output shaft holding portion 42 in the first direction D1.

[0064] The clutch device 10 of this embodiment includes a weight member 122 configured to be movable from a radially inner position to an outer position by the centrifugal force accompanying the rotation of the clutch housing 30, and a centrifugal clutch mechanism 120 that presses the input side rotating plate 20 and the output side rotating plate 22 together when the weight member 122 is in the outer position to transmit the rotational driving force of the input shaft to the output shaft 15, and that releases the pressing force between the input side rotating plate 20 and the output side rotating plate 22 when the weight member 122 is in the inner position to interrupt the transmission of the rotational driving force of the input shaft to the output shaft 15, and the centrifugal clutch mechanism 120 is located radially outside the oil groove 42P and on the extension line 42PL of the oil groove 42P. According to the above embodiment, the centrifugal clutch mechanism 120 can be supplied with clutch oil flowing out from the output shaft 15 through the oil groove 42P.

[0065] The clutch device 10 of this embodiment is equipped with an auxiliary clutch plate 150 which is configured to be pressed by the centrifugal clutch mechanism 120 when the input side rotating plate 20 and the output side rotating plate 22 are pressed together, thereby enabling the rotational driving force of the input shaft to be transmitted to the output shaft 15, and which is released from the pressure by the centrifugal clutch mechanism 120 when the pressing force between the input side rotating plate 20 and the output side rotating plate 22 is released, thereby blocking the transmission of the rotational driving force of the input shaft to the output shaft 15. The auxiliary clutch plate 150 is fixed to the output shaft 15 and is adjacent to the end face 42D1 in the first direction D1 of the output shaft holding portion 42, and at least a portion of the auxiliary clutch plate 150 is in surface contact with at least a portion of the end face 42D1 in the first direction D1 of the output shaft holding portion 42. According to the above embodiment, the auxiliary clutch plate 150 is adjacent to the end face 42D1 of the output shaft holding portion 42 in the first direction D1, and at least a portion of the auxiliary clutch plate 150 is in surface contact with at least a portion of the end face 42D1 of the output shaft holding portion 42 in the first direction D1, but the clutch oil flowing out from the output shaft 15 through the oil groove 42P can be supplied to the outside from the radial outer edge of the end face 42D1 of the output shaft holding portion 42 in the first direction D1.

[0066] In the clutch device 10 of this embodiment, the auxiliary clutch plate 150 has a fitting portion 152 that fits onto the output shaft 15, and a disk portion 154 that is located radially outward of the fitting portion 152, and the length L1 in the direction D1 of the fitting portion 152 is longer than the length L2 in the direction D1 of the disk portion 154. According to the above aspect, the auxiliary clutch plate 150 is reliably fitted onto the output shaft 15, and the auxiliary clutch plate 150 can be arranged compactly.

[0067] In the clutch device 10 of this embodiment, the centrifugal clutch mechanism 120 is configured to be able to press the disk portion 154, and the disk portion 154 is located on the second direction D2 side with respect to the axial center 152C of the fitting portion 152. According to the above aspect, the centrifugal clutch mechanism 120 can be made compact.

[0068] In the clutch device 10 of this embodiment, the disk portion 154 has an abutment surface 154F which is an end face on the second direction D2 side and is pressed against the centrifugal clutch mechanism 120. According to the above-described aspect, the centrifugal clutch mechanism 120 can press the entire auxiliary clutch plate 150 by pressing the abutment surface 154F.

[0069] The clutch device 10 of this embodiment includes a friction material 170 provided between the contact surface 154F and the centrifugal clutch mechanism 120. According to the above aspect, the rotational driving force is reliably transmitted by the friction material 170 to the auxiliary clutch plate 150 via the centrifugal clutch mechanism 120. In addition, since the clutch oil flowing out from the output shaft 15 can be supplied to the friction material 170, wear of the friction material 170 can be suppressed.

[0070] In the clutch device 10 of this embodiment, a plurality of fitting teeth 47 that extend in the axial direction of the output shaft 15 and fit with the output shaft 15 are formed on the inner wall 45A that defines the insertion hole 45 of the output shaft holding portion 42, and at least a part of the end face 42D1 in the first direction D1 of the output shaft holding portion 42 is located closer to the first direction D1 than the end face 47D1 in the first direction D1 of the fitting teeth 47, and a step portion 48 is formed between the end face 42D1 in the first direction D1 of the output shaft holding portion 42 and the end face 47D1 in the first direction D1 of the fitting teeth 47. According to the above aspect, the clutch oil that flows out from the output shaft 15 is once held in the step portion 48 and then flows into the oil groove 42P, so that more clutch oil can flow from the oil groove 42P to the outside.

[0071] In the clutch device 10 of the present embodiment, the step portion 48 is formed around the entire circumference of the output shaft holding portion 42. According to the above aspect, even if the communication hole 15B of the output shaft 15 and the oil groove 42P are misaligned in the circumferential direction (phase), the clutch oil flowing through the oil flow passage 15H of the output shaft 15 can be reliably supplied to the oil groove 42P.

[0072] In the clutch device 10 of this embodiment, the centrifugal clutch mechanism 120 has a support member 128 that holds the weight member 122 so as to be movable in the radial direction, and is provided with a friction material 175 provided between the support member 128 and the clutch center 40. According to the above-mentioned aspect, it is possible to supply clutch oil to the friction material 175, and seizure of the friction material 175 can be suppressed.

[0073] In the clutch device 10 of this embodiment, the auxiliary clutch plate 150 is fixed to the output shaft 15 and is adjacent to the end face 42D1 in the first direction D1 of the output shaft holding part 42. According to the above aspect, the auxiliary clutch plate 150 is adjacent to the end face 42D1 in the first direction D1 of the output shaft holding part 42, and the clutch oil that flows out from the output shaft 15 via the oil groove 42P can be supplied to the outside from the radial outer edge 42DO of the end face 42D1 of the output shaft holding part 42 in the first direction D1.

[0074] In the clutch device 10 of this embodiment, the entire end face 42D1 in the first direction D1 of the output shaft holding portion 42 is located on the first direction side D1 with respect to the end face 47D1 in the first direction D1 of the fitting tooth 47. According to the above-described aspect, the step portion 48 is formed around the entire circumference of the insertion hole 45, so that a larger amount of clutch oil can be held in the step portion 48.

[0075] In the clutch device 10 of this embodiment, when viewed from the axial direction of the output shaft 15, a diameter R1 of a portion of the insertion hole 45 defined by an inner edge 42I of an end face 42D1 of the output shaft holding portion 42 in the first direction D1 is larger than a diameter R2 of a portion of the insertion hole 45 defined by a radially inner edge 47I of the fitting tooth 47. According to the above aspect, a sufficient radial length of the stepped portion 48 can be ensured, so that the stepped portion 48 can hold a larger amount of clutch oil.

[0076] In the clutch device 10 of this embodiment, the output shaft 15 includes a main body 15A that extends in the direction D and forms an oil flow passage 15H through which the clutch oil flows, and a communication hole 15B that is formed in the main body 15A, extends in the radial direction, and communicates with the oil flow passage 15H. According to the above aspect, the clutch oil flowing through the oil flow passage 15H of the main body 15A flows into the oil groove 42P via the communication hole 15B.

[0077] In the clutch device 10 of the present embodiment, at least a portion of the communication hole 15B is located, with respect to the direction D (i.e., the axial direction of the output shaft 15), between the end face 42D1 in the first direction D1 of the output shaft holding portion 42 and the end face 47D1 in the first direction D1 of the fitting tooth 47. According to the above aspect, it is possible to allow more clutch oil flowing through the oil flow passage 15H of the main body portion 15A to flow to the step portion 48.

[0078] 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.

[0079] In the above-described embodiment, the clutch center 40 includes a first clutch center 41 and a second clutch center 51, and the first clutch center 41 and the second clutch center 51 are assembled together for use, but the first clutch center 41 and the second clutch center 51 may be integrated.

[0080] In the embodiment described above, the clutch oil does not flow through the insertion hole 45 in the axial direction of the output shaft 15, but it may flow therethrough.

[0081] In the above-described embodiment, the clutch center 40 includes the center-side assist cam surface 60A and the center-side slipper cam surface 60S, but the clutch center 40 does not have to include the center-side assist cam surface 60A and the center-side slipper cam surface 60S. Also, the pressure plate 70 includes the pressure-side assist cam surface 90A and the pressure-side slipper cam surface 90S, but the pressure plate 70 does not have to include the pressure-side assist cam surface 90A and the pressure-side slipper cam surface 90S.

[0082] In the above-described embodiment, an engine is used as the power source, but the power source is not limited to an engine and may be, for example, an electric motor.

[0083] The saddle-type vehicle in this embodiment is a vehicle on which a driver straddles and rides. The saddle-type vehicle is not limited to a motorcycle such as a scooter. The saddle-type vehicle may be, for example, a three-wheeled motor vehicle, an ATV (All Terrain vehicle), a snowmobile, or the like. [Explanation of symbols]

[0084] 10 Clutch device 15 Output shaft 15A Main unit 15B Communication hole 15H Oil flow path 20 Input side rotating plate 22 Output side rotating plate 30 Clutch housing 40 Clutch center 41 First clutch center 42 Output shaft holder 42D1 End face in the first direction 42P Oil groove 42PL extension line 42DO Outer edge 42I Inner border 45 Insertion hole 45A Inner wall 47 Interdigitating teeth 47D1 End face in the first direction 47I Inner diameter edge 48 Step 70 Pressure Plate 120 Centrifugal clutch mechanism 122 Weight material 128 Support member 150 Auxiliary clutch plate 152 Fitting part 154 Disc Section 154F Contact surface 170 Friction material 175 Friction materials (other friction materials)

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 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 part of a plurality of output side rotating plates that are arranged alternately with the input side rotating plate, and that is capable of pressing the input side rotating plate and the output side rotating plate, The clutch center includes an output shaft holding portion to which the output shaft is connected, the output shaft holding portion includes an insertion hole into which the output shaft is inserted, a clutch device in which, 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, an oil groove is formed on the end face in the first direction of the output shaft holding portion, the oil groove communicating with the insertion hole and extending radially of the output shaft and from the insertion hole to the radial outer edge of the end face in the first direction, and through which clutch oil flowing out from the output shaft flows.

2. a centrifugal clutch mechanism having a weight member configured to be movable from an inner position in the radial direction to an outer position by centrifugal force accompanying rotation of the clutch housing, and which presses the input side rotating plate and the output side rotating plate together when the weight member is at the outer position in the radial direction, thereby enabling the rotational driving force of the input shaft to be transmitted to the output shaft, and which releases the pressing force between the input side rotating plate and the output side rotating plate when the weight member is at the inner position, thereby interrupting the transmission of the rotational driving force of the input shaft to the output shaft, 2. The clutch device according to claim 1, wherein the centrifugal clutch mechanism is located radially outside the oil groove and on an extension of the oil groove.

3. an auxiliary clutch plate configured to be pressed by the centrifugal clutch mechanism when the input side rotating plate and the output side rotating plate are in pressure contact with each other, thereby enabling the rotational driving force of the input shaft to be transmitted to the output shaft, and to be released from the pressure of the centrifugal clutch mechanism when the pressure contact force between the input side rotating plate and the output side rotating plate is released, thereby blocking the transmission of the rotational driving force of the input shaft to the output shaft; the auxiliary clutch plate is fixed to the output shaft and is adjacent to an end surface of the output shaft holding portion in the first direction, 3. The clutch device according to claim 2, wherein at least a portion of the auxiliary clutch plate and at least a portion of an end face of the output shaft holding portion in the first direction are in surface contact with each other.

4. The auxiliary clutch plate is a fitting portion that fits onto the output shaft; a disk portion located radially outward of the fitting portion, 4. The clutch device according to claim 3, wherein a length of the fitting portion in the axial direction of the output shaft is longer than a length of the disk portion in the axial direction.

5. The centrifugal clutch mechanism is configured to be able to press the disk portion, The clutch device according to claim 4 , wherein the disk portion is located on the second direction side relative to a center of the fitting portion in the axial direction.

6. 6. The clutch device according to claim 5, wherein the disk portion has an abutment surface which is an end surface on the second direction side and is pressed against the centrifugal clutch mechanism.

7. 7. The clutch device of claim 6, further comprising a friction material disposed between said abutment surface and said centrifugal clutch mechanism.

8. an inner wall of the output shaft holding portion that defines the insertion hole is formed with a plurality of fitting teeth that extend in the axial direction of the output shaft and fit with the output shaft; At least a part of an end surface of the output shaft holding portion in the first direction is located on the first direction side of an end surface of the engagement tooth in the first direction, 3. The clutch device according to claim 2, wherein a step is formed between an end face of the output shaft holding portion in the first direction and an end face of the engaging teeth in the first direction.

9. The clutch device according to claim 8 , wherein the step portion is formed around the entire circumference of the output shaft holding portion.

10. The centrifugal clutch mechanism has a support member that holds the weight member so as to be movable in the radial direction, 3. The clutch device according to claim 2, further comprising another friction material provided between said support member and said clutch center.

11. an auxiliary clutch plate configured to be pressed by a centrifugal clutch mechanism when the input side rotating plate and the output side rotating plate are in pressure contact with each other, thereby enabling the rotational driving force of the input shaft to be transmitted to the output shaft, and to be released from the pressure of the centrifugal clutch mechanism when the pressure contact force between the input side rotating plate and the output side rotating plate is released, thereby blocking the transmission of the rotational driving force of the input shaft to the output shaft; 2. The clutch device according to claim 1, wherein the auxiliary clutch plate is fixed to the output shaft and is adjacent to an end surface of the output shaft holding portion in the first direction.

12. an inner wall of the output shaft holding portion that defines the insertion hole is formed with a plurality of fitting teeth that extend in the axial direction of the output shaft and fit with the output shaft; At least a part of an end surface of the output shaft holding portion in the first direction is located on the first direction side of an end surface of the engagement tooth in the first direction, 2. The clutch device according to claim 1, wherein a step is formed between an end face of the output shaft holding portion in the first direction and an end face of the engaging teeth in the first direction.

13. The clutch device according to claim 12 , wherein an entire end face of the output shaft holding portion in the first direction is located on the first direction side of an end face of the mating teeth in the first direction.

14. 14. The clutch device according to claim 12 or 13, wherein, when viewed from the axial direction of the output shaft, a diameter of a portion of the insertion hole defined by an inner edge of an end face of the output shaft holding portion in the first direction is larger than a diameter of a portion of the insertion hole defined by an inner edge of the mating teeth in the radial direction.

15. The clutch device according to claim 12 or 13, wherein the step portion is formed over the entire circumference of the output shaft holding portion.

16. The output shaft is provided. The output shaft is a main body portion extending in the axial direction and forming an oil flow path through which clutch oil flows; 14. The clutch device according to claim 12, further comprising: a communication hole formed in the main body portion, extending in the radial direction, and communicating with the oil flow path.

17. 17. The clutch device according to claim 16, wherein at least a portion of the communication hole is located between an end face of the output shaft holding portion in the first direction and an end face of the mating teeth in the first direction with respect to the axial direction of the output shaft.

Images