JP5648578B2 - Multi-plate automatic centrifugal clutch device - Google Patents

Description

  The present invention relates to a multi-plate automatic centrifugal clutch device.

  Patent Document 1 discloses a multi-plate automatic centrifugal clutch device 200 as shown in FIG. 10 applied to an engine unit of a motorcycle. The clutch device 200 includes a clutch housing 201, a sleeve hub 202, a drive plate 203, a driven plate 204, and a centrifugal roller 205.

  The clutch housing 201 is spline-coupled to a driven shaft 206 serving as an input unit, and supports a plurality of drive plates 203 with an outer peripheral wall 207. The sleeve hub 202 is spline-coupled to a reduction gear 208 serving as an output portion, and supports a plurality of driven plates 204 with an outer cylinder portion 209. Each driven plate 204 is disposed between adjacent drive plates 203 so as to be alternately superposed. These drive plate 203 and driven plate 204 are accommodated inside the clutch housing 201.

  The centrifugal roller 205 is disposed in the clutch housing 201, and the drive plate 203 and the driven plate 204 are pressed and frictionally joined by the action of the centrifugal force generated by the rotation of the clutch housing 201, so that the clutch-in state (connected state) is established. . In this clutch-in state, the driving force from the driven shaft 206 is transmitted to the reduction gear 208 via the clutch housing 201, the drive plate 203, the driven plate 204, and the sleeve hub 202.

  When the rotational speed of the clutch housing 201 decreases and the centrifugal force acting on the centrifugal roller 205 decreases, the frictional connection between the drive plate 203 and the driven plate 204 is released, and the clutch device 200 is in the clutch-off state (disengaged state). ), And the transmission of the driving force of the driven shaft 206 to the reduction gear 208 is interrupted.

JP 2007-113653 A

  Incidentally, since the clutch housing 201 supports the drive plate 203 by the outer peripheral wall 207, the dimension of the outer peripheral wall 207 is determined by the outer diameter dimension of the drive plate 203. The maximum amount of movement of the centrifugal roller 205 disposed in the clutch housing 201 outward in the clutch radial direction by the action of centrifugal force is regulated by the inner peripheral surface 207A of the outer peripheral wall 207 of the clutch housing 201. Therefore, the maximum movement position of the centrifugal roller 205 outward in the clutch radial direction is limited by the outer diameter of the drive plate 203.

  For this reason, the centrifugal force generated in the centrifugal roller 205 cannot be increased, and accordingly, the pressing force with which the centrifugal roller 205 presses the drive plate 203 and the driven plate 204 cannot be increased by the action of the centrifugal force. As a result, the power transmission torque transmitted from the driven shaft 206 to the reduction gear 208 cannot be improved.

  In order to improve the power transmission torque of the clutch device 200, it is necessary to enlarge the outer diameters of the drive plate 203 and the driven plate 204 and further increase the number of the drive plate 203 and the driven plate 204. There is a problem that the size of the apparatus 200 increases and the cost increases.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a multi-plate automatic centrifugal clutch device capable of reducing the size and cost of the device in consideration of the above circumstances.

The present invention accommodates a plurality of drive plates that are integrally rotated on the input side, a plurality of driven plates that are integrally rotated on the output side, and these drive plates and driven plates that can be alternately stacked on the inside. A clutch housing, and a centrifugal roller that presses and frictionally joins the drive plate and the driven plate by the action of centrifugal force generated by the rotation of the input unit, and the friction between the drive plate and the driven plate In the multi-plate automatic centrifugal clutch device that transmits power from the input unit to the output unit by joining, a sleeve hub that is integrally rotated with the input unit is provided, and a clutch radial in the centrifugal roller is provided on the outer cylindrical portion of the sleeve hub. The sleeve hub inner cylinder is formed with a centrifugal roller restricting portion for restricting movement in the direction. In the drive plate is supported, also, the clutch housing is provided on the rotating integrally with the output section, the driven plate in the outer peripheral wall of the clutch housing is supported, the centrifugal rollers to move the clutch radial direction by the centrifugal force The maximum movement restriction position is set to the outside in the clutch radial direction with respect to the inner peripheral surface of the outer peripheral wall of the clutch housing.

  According to the present invention, the maximum movement restriction position of the centrifugal roller that moves in the clutch radial direction by the centrifugal force is set to the outside in the clutch radial direction from the inner surface of the outer peripheral wall of the clutch housing, and thus acts on the centrifugal roller. Centrifugal force can be increased. Therefore, since the pressing force for pressing the drive plate and the driven plate can be increased based on the centrifugal force, the power transmission torque by the clutch device can be improved. As a result, it is not necessary to increase the outer diameter of the drive plate and the driven plate and increase the number of these plates in order to improve the power transmission torque, so that the clutch device can be reduced in size and cost can be reduced.

1 is a right side view showing a motorcycle equipped with an engine unit to which an embodiment of a multi-plate automatic centrifugal clutch device according to the present invention is applied. Sectional drawing which shows the engine unit of FIG. Sectional drawing which shows the multi-plate type automatic centrifugal clutch apparatus provided in the engine unit of FIG. The perspective view which shows the sleeve hub of FIG. The perspective view which shows the clutch inner plate of FIG. FIG. 4 is a perspective view showing a drive plate on the spring support side of FIG. 3. FIG. 4 is a perspective view showing a drive plate on the spring receiving side of FIG. 3. The perspective view which shows the clutch housing of FIG. The perspective view which shows the driven plate of FIG. Sectional drawing which shows the conventional multi-plate type automatic centrifugal clutch apparatus.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the present invention is not limited to these embodiments. FIG. 1 is a right side view showing a motorcycle equipped with an engine unit to which an embodiment of a multi-plate automatic centrifugal clutch device according to the present invention is applied. In the present embodiment, front / rear, left / right, and upper / lower expressions are based on the driver when riding the motorcycle.

  The body frame 2 of the motorcycle 1 is an underbone type, and a main frame pipe 4 extends rearward and obliquely downward from a head pipe 3 located at the frontal region, and a pair of left and right rear frames is disposed from the vicinity of the rear end of the main frame pipe 4. The frame pipe 5 is configured to extend rearward and obliquely upward. Engine brackets 6 and 7 are provided in the vicinity of the connecting portion between the main frame pipe 4 and the rear frame pipe 5.

  A front fork 10 that supports the front wheel 9 is pivotally supported on the head pipe 3 together with a handle bar 11, a headlamp 12, a front fender 13, and the like so as to be rotatable left and right. On the other hand, a swing arm 17 that supports a rear wheel 16 is pivotally supported on a pivot shaft 15 installed on the engine bracket 7 so as to be rotatable up and down. A rear cushion unit 18 is connected between the rear portion of the swing arm 17 and the rear portion of the rear frame pipe 5.

  For example, an engine unit 20 having an air-cooled single-cylinder four-cycle engine 35 is suspended and mounted on the engine brackets 6 and 7, and the output is transmitted to the rear wheel 16 by a chain unit 21 provided on the left side of the rear wheel 16. Is done. The engine unit 20 is provided with a step 22, and the exhaust muffler 23 of the engine unit 20 is disposed on the right side of the rear wheel 16. The front portion of the vehicle body frame 2 is covered with a synthetic resin front cover 24 and a leg shield 25.

  A storage box 26 having a bottomed box shape made of synthetic resin and having an upper surface opened is fixed to an upper portion in the vicinity of a connecting portion between the main frame pipe 4 and the rear frame pipe 5. A fuel tank 28 is provided between the rear frame pipes 5 behind the storage box 26. The storage box 26 has a capacity capable of storing a helmet or the like.

  A seating seat 30 is provided so as to cover the upper part of the storage box 26 and the fuel tank 28. The front end portion of the seating seat 30 is pivotally supported by a seat hinge 31 provided at the front upper portion of the storage box 26. The seat 30 is opened and closed by lifting the rear end upward with the seat hinge 31 as an axis, and thereby, articles are taken into and out of the storage box 26 and fuel is supplied to the fuel tank 28.

  The lower side of the seating seat 30 and the left and right sides of the storage box 26 and the fuel tank 28 are covered with a pair of left and right synthetic resin frame covers 32. A synthetic resin rear fender 33 that covers the rear wheel 16 from above is provided behind the storage box 26 and below the fuel tank 28. Further, a tail lamp 34 is provided at the rear end of the frame cover 32.

  As shown in FIG. 2, the engine unit 20 includes an engine 35, a belt-type continuously variable transmission (CVT) 36, a multi-plate automatic centrifugal clutch device (hereinafter simply referred to as a clutch device) 37, and a deceleration transmission mechanism 38. And is configured.

  As shown in FIGS. 1 and 2, the engine 35 includes a cylinder 40 and a cylinder head 41 which are installed on the front surface of a crankcase 39 so as to be inclined forward to substantially horizontal. A piston 42 is slidably inserted into the engine 40, and one end of a connecting rod 43 is connected to the piston 42. The other end of the connecting rod 43 is connected to a crank pin 44 of a crankshaft 54 (described later). The connecting rod 43 converts the reciprocating motion of the piston 42 into the rotational motion of the crankshaft 54.

  A combustion chamber 45 is formed in the cylinder head 41, and an intake port and an exhaust port (not shown) are formed in communication with the combustion chamber 45. A spark plug 46 is inserted into the combustion chamber 45. An intake pipe 47 (FIG. 1) is connected to the intake port, and an exhaust pipe 48 is connected to the exhaust port. The exhaust pipe 48 extends rearward from the cylinder head 41 and is connected to the exhaust muffler 23.

  As shown in FIG. 2, a cam chain 50 is disposed in a cam chain chamber 49 formed in the cylinder 40 and the cylinder head 41. The cam chain 50 is wound around the cam drive sprocket 51 of the crankshaft 54 and the cam driven sprocket 53 of the camshaft 52. With this cam chain 50, the cam shaft 52 rotates according to the rotation of the crankshaft 54, and opens and closes an intake valve (not shown) for opening and closing the intake port and an exhaust valve (not shown) for opening and closing the exhaust port.

  The crankcase 39 is configured by joining a left crankcase 39A and a right crankcase 39B, and a crankshaft 54 is accommodated therein. The crankshaft 54 extends horizontally in the vehicle width direction and is disposed horizontally, and is rotatably supported by the left crankcase 39A via a bearing 55 and by the right crankcase 39B via a bearing 56, respectively.

  A generator case 58 that houses the generator 57 is attached to the left side of the front half of the left crankcase 39A. The left end portion of the crankshaft 54 extends through the left crankcase 39A into the generator case 58, and the rotor 59 of the generator 57 is attached to the left end portion. The stator 60 of the generator 57 is attached to the generator case 58 so as to face the rotor 59. The rotor 59 rotates around the stator 60 by the rotation of the crankshaft 54, thereby generating electric power.

  A transmission case 61 that houses the belt type continuously variable transmission 36 is attached to the right side of the right crankcase 39B. The transmission case 61 is configured to be separated from the crankcase 39, and is connected between the transmission inner case 61A joined to the right crankcase 39B and the transmission inner case 61A, and between the transmission inner case 61A. And a transmission outer case 61 </ b> B that forms the belt chamber 62. A belt type continuously variable transmission 36 is accommodated in the belt chamber 62.

  The right end portion of the crankshaft 54 passes through the right crankcase 39B and the transmission inner case 61A and extends into the belt chamber 62, and the drive pulley 63 of the belt type continuously variable transmission 36 is integrally rotated with the right end portion. Connected. A driven shaft 64 is disposed in the rear half of the crankcase 39 in parallel with the crankshaft 54. The driven shaft 64 is rotatably supported by a gear box cover 77 (described later) via a bearing 65 and by a transmission inner case 61A via a bearing 66. A right half of the driven shaft 64 is in the belt chamber 62, and a driven pulley 67 of the belt-type continuously variable transmission 36 is connected to the right half through a sleeve 68 so as to be integrally rotated.

  The belt type continuously variable transmission 36 is wound around the drive pulley 63, the driven pulley 67, and the drive pulley 63 and the driven pulley 67, so that the rotational force (driving force) of the drive pulley 63 is driven pulley 67. And a V-belt 69 that transmits to the head.

  In the drive pulley 63, a fixed face 63A and a movable face 63B are arranged to face each other, and the fixed face 63A is fixed to the crankshaft 54. In addition, the movable face 63B is attached to the crankshaft 54 so as to be integrally rotatable and slidable in the axial direction. A cam surface 70 is formed on the back surface of the movable face 63 </ b> B, and a weight roller 72 is disposed between the cam plate 71 fixed to the right end portion of the crankshaft 54 and the cam surface 70.

  The driven pulley 67 has a fixed face 67A and a movable face 67B arranged to face each other. The fixed face 67A is fixed to the outer periphery of the sleeve 68 fixed to the driven shaft 64. In addition, the movable face 67B is attached to the sleeve 68 so as to be integrally rotatable and slidable in the axial direction. A spring 74 is interposed between the movable face 67 </ b> B and a spring receiver 73 fixed to the sleeve 68. Due to the biasing force of the spring 74, the movable face 67B is constantly biased toward the fixed face 67A.

  A V-belt 69 is disposed between the fixed face 63A and the movable face 63B of the drive pulley 63 and between the fixed face 67A and the movable face 67B of the driven pulley 67. The belt winding diameter of the drive pulley 63 and the belt winding diameter of the driven pulley 67 are determined by the centrifugal force acting on the weight roller 72 that presses the movable face 63B of the drive pulley 63 toward the fixed face 63A, and the movable face of the driven pulley 67. It is determined by the magnitude relationship with the urging force of the spring 74 that urges 67B toward the fixed face 67A. Thereby, the reduction ratio of the belt type continuously variable transmission 36 is automatically determined.

  That is, when the rotation speed of the crankshaft 54 increases, the weight roller 72 moves outward in the radial direction of the drive pulley 63 by the action of centrifugal force. As a result, the movable face 63B of the drive pulley 63 moves in the axial direction of the crankshaft 54 and approaches the fixed face 63A, and the belt winding diameter of the drive pulley 63 increases. At this time, the driven pulley 67 moves on the sleeve 68 along the axial direction of the driven shaft 64 against the urging force of the spring 74 and moves away from the fixed face 67A. The hanging diameter is reduced. Thereby, the reduction ratio of the belt type continuously variable transmission 36 is reduced.

  Further, when the rotational speed of the crankshaft 54 decreases, the centrifugal force acting on the weight roller 72 is reduced, the weight roller 72 moves inward in the radial direction of the drive pulley 63, and the urging force of the spring 74 is driven by the driven pulley. 67 movable faces 67B are moved closer to the fixed face 67A side. As a result, the belt winding diameter of the drive pulley 63 is reduced, the belt winding diameter of the driven pulley 67 is increased, and the reduction ratio of the belt type continuously variable transmission 36 is increased. In this way, the belt-type continuously variable transmission 36 continuously changes the rotational speed of the crankshaft 54 to rotate the driven shaft 64.

  As will be described in detail later, the clutch device 37 is disposed between the driven shaft 64 and the deceleration mission mechanism 38. In the clutch-in state (connected state), the rotational force (driving force) of the driven shaft 64 is reduced. Is transmitted to the first reduction gear 75A, and in the clutch-off state (disengaged state), the transmission of the driving force is interrupted. The clutch-in state and clutch-off state of the clutch device 37 are automatically switched according to the rotational speed of the driven shaft 64. The clutch device 37 is a so-called wet multi-plate clutch, and a drive plate 90 and a driven plate 91 housed in a clutch housing 87 described later are in an atmosphere in which lubricating oil exists.

  The speed reduction transmission mechanism 38 is disposed between the clutch device 37 and the output shaft 76, and uses the rotational force of the driven shaft 64 as a gear train (first reduction gear 75A, second reduction gear 75B, third reduction gear 75C, 4 decelerating gear 75D) and transmitting to output shaft 76. The output shaft 76 is rotatably supported by the left crankcase 39A and a gear box cover 77 joined to the left crankcase 39 via bearings 78 and 79, respectively. An intermediate shaft 80 is also rotatably supported by the left crankcase 39A and the chia box cover 77 via bearings 81 and 82, respectively.

  As shown in FIG. 3, the first reduction gear 75A is rotatably supported at the left end of the driven shaft 64 via a bearing 83, and is splined to a clutch housing 87 (described later) of the clutch device 37. Yes. As shown in FIG. 2, the second reduction gear 75B is rotatably integrated with the intermediate shaft 80 and meshes with the first reduction gear 75A. The third reduction gear 75C is formed on the intermediate shaft 80. The fourth reduction gear 75D is rotatably integrated with the output shaft 76 and meshes with the third reduction gear 75C. The reduction transmission mechanism 38 reduces the rotational force (driving force) of the driven shaft 64 to a desired reduction ratio and transmits it to the output shaft 76.

  The left end portion of the output shaft 76 projects outward from the left crankcase 39A, and a drive sprocket 84 is fixed to the left end portion. The drive sprocket 84 is wound around a drive chain 85 for transmitting the driving force of the output shaft 76 to the rear wheel 16 (FIG. 1), thereby driving the rear wheel 16. The drive chain 85 is a component of the chain unit 21 shown in FIG.

  2 and 3, the clutch device 37 transmits the driving force of the driven shaft 64 to the first reduction gear 75A of the reduction transmission mechanism 38 in the clutch-in state, and the driving force in the clutch-off state. Transmission, and includes a sleeve hub 86, a clutch housing 87, a centrifugal roller 88, and a biasing spring 89 as a biasing member. A plurality of drive plates 90 and driven plates 91 serving as clutch plates are accommodated in the clutch housing 87.

  The sleeve hub 86 is formed in a substantially bottomed cylindrical shape as shown in FIGS. 3 and 4, and includes a boss portion 92, an inner cylindrical portion 93 as a cylindrical portion, and an outer cylindrical portion 94 in order from the inside to the outside. . Spline teeth 95 are formed on the inner surface of the boss portion 92. The sleeve hub 86 is spline-coupled to a driven shaft 64 as an input portion via the spline teeth 95, and is provided integrally with the driven shaft 64.

  The inner tube portion 93 of the sleeve hub 86 is partially cut off in the circumferential direction, and uneven teeth 96 are formed on the outer periphery. The uneven teeth 96 mesh with the uneven teeth 97 formed on the inner periphery of the drive plate 90A (FIG. 3), the drive plate 90B (FIGS. 3 and 6), and the drive plate 90C (FIGS. 3 and 7). Accordingly, the drive plate 90 (drive plates 90A, 90B, and 90C) is supported by the inner cylinder portion 93 of the sleeve hub 86 and is provided integrally with the sleeve hub 86 so as to rotate.

  Here, as shown in FIG. 3, the drive plate 90 </ b> B is located on the innermost side of the sleeve hub 86 (outermost side in the clutch housing 87), and is the drive plate 90 on the support side of the urging spring 89. The drive plate 90C is located on the outermost side of the sleeve hub 86 (innermost in the clutch housing 87), and is the drive plate 90 on the receiving side of the urging spring 89. A plurality of drive plates 90A are disposed between the drive plates 90B and 90C. These drive plates 90A, 90B and 90C are arranged side by side with a space in the axial direction of the sleeve hub 86 (that is, the axial direction of the driven shaft 64).

  A clutch inner plate 98 shown in FIG. 5 is installed inside the outer cylinder portion 94 of the sleeve hub 86. In this clutch inner plate 98, a plurality of positioning pieces 100 are integrally formed at equal circumferential positions of the base ring 99, and a centrifugal roller 88 is disposed between the positioning pieces 100. The base ring 99 is formed in a substantially triangular shape in cross section, and the inclined surface is formed as a cam surface 101 that guides the centrifugal roller 88.

  The clutch housing 87 is formed in a substantially bottomed cylindrical shape shown in FIGS. 3 and 8, and includes a boss portion 102 on the inner side and an outer peripheral wall 103 on the outer side. Spline teeth 104 are formed on the inner surface of the boss portion 102. The clutch housing 87 is spline-coupled to the first reduction gear 75A as an output portion via the spline teeth 104, and is provided integrally with the first reduction gear 75A. In FIG. 3, reference numeral 105 denotes a nut, and the clutch housing 87 is fastened to the first reduction gear 75 </ b> A via the washer 106 by the nut 105. The first reduction gear 75A is rotatably supported with respect to the driven shaft 64 via the bearing 83 as described above.

  Concave portions 107 are formed at equal intervals in the circumferential direction on the outer peripheral wall 103 of the clutch housing 87. A projection 108 protruding from the outer periphery of the driven plate 91 shown in FIGS. 3 and 9 is fitted into these recesses 107. Thus, the plurality of driven plates 91 are supported by the outer peripheral wall 103 of the clutch housing 87 and are provided integrally with the clutch housing 87 so as to rotate.

  Here, the plurality of driven plates 91 are arranged side by side with an interval in the axial direction of the clutch housing 87 (that is, the axial direction of the driven shaft 64). Further, the clutch housing 87 and the sleeve hub 86 are arranged so that their openings face each other, and the driven plate 91 supported by the clutch housing 87 is located between adjacent drive plates 90 supported by the sleeve hub 86. Be placed. Thereby, the drive plate 90 and the driven plate 91 are accommodated in the clutch housing 87 so as to be alternately superposed.

  As shown in FIG. 3, a plurality of the centrifugal rollers 88 are arranged in a space 109 surrounded by the inner cylindrical portion 93 and the outer cylindrical portion 94 of the sleeve hub 86 and the drive plate 90B. Each centrifugal roller 88 is positioned and positioned between positioning pieces 100 of a clutch inner plate 98 that is also installed in the space 109. These centrifugal rollers 88 move outward in the clutch radial direction by the action of centrifugal force generated by rotation of the driven shaft 64 (that is, rotation of the sleeve hub 86). At this time, the base ring 98 of the clutch inner plate 98 is moved. Rolling on the cam surface 101 and moving in the clutch thrust direction, pressing the drive plate 90B toward the drive plate 90C, and friction between the drive plate 90 (drive plates 90A, 90B and 90C) and the driven plate 91 Join.

  The biasing spring 89 generates a biasing force that resists the pressing force that presses the drive plate 90 and the driven plate 91 in the clutch thrust direction based on the centrifugal force acting on the centrifugal roller 88. A plurality of (three in this embodiment) are interposed in a sandwiched state between the drive plate 90C and the drive plate 90C. As shown in FIG. 6, support bars 110 are implanted in the drive plate 90 </ b> B at a plurality of locations in the circumferential direction (three locations in this embodiment), and the support bars 110 are inserted into the biasing springs 89. Then, the biasing spring 89 is supported.

  Further, as shown in FIG. 3, the urging spring 89 is disposed between the inner cylindrical portion 93 of the sleeve hub 86 and the driven plate 91 in the clutch radial direction. This position is a position where the centrifugal roller 88 and the urging spring 89 partially overlap in the clutch Asian direction when the centrifugal roller 88 moves inwardly with respect to the sleeve hub 86 in the clutch radial direction. (Refer to the upper half of FIG. 3).

  The clutch device 37 as described above switches between a clutch-in state (connected state) and a clutch-off state (disconnected state) depending on the magnitude relationship between the centrifugal force acting on the centrifugal roller 88 and the biasing force of the biasing spring 89. It is done.

  That is, when the rotational speed of the sleeve hub 86 becomes equal to or higher than the predetermined rotational speed due to the rotation of the driven shaft 64, the centrifugal roller 88 moves outward in the clutch radial direction by the action of centrifugal force, and on the cam surface 101 of the clutch inner plate 98. Roll. At this time, since the centrifugal force acting on the centrifugal roller 88 is greater than the urging force of the urging spring 89, the centrifugal roller 88 moves the drive plate 90B toward the drive plate 90C against the urging force of the urging spring 89. Press in the direction of the clutch thrust. As a result, the drive plate 90 and the driven plate 91 are frictionally joined to enter a clutch-in state, and the driving force of the driven shaft 64 passes through the sleeve hub 86, the drive plate 90, the driven plate 91, and the clutch housing 87, and the first reduction gear 75A. Is transmitted to. This clutch-in state is shown in the lower half of FIG.

  Further, when the rotational speed of the driven shaft 64 decreases and the rotational speed of the sleeve hub 86 becomes less than the predetermined rotational speed, the centrifugal force acting on the centrifugal roller 88 decreases, and the centrifugal roller 88 moves inward in the clutch radial direction. To do. At this time, since the urging force of the urging spring 89 becomes larger than the centrifugal force, the urging force of the urging spring 89 releases the frictional connection between the drive plate 90 and the driven plate 91 and the clutch is turned off. The driving force of the driven shaft 64 is not transmitted to the first reduction gear 75A. This clutch-off state is shown in the upper half of FIG.

  In the clutch device 37 described above, the outer cylinder portion 94 of the sleeve hub 86 functions as a centrifugal roller restricting portion that restricts the movement of the centrifugal roller 88 when the centrifugal roller 88 moves outward in the clutch radial direction. That is, the centrifugal roller 88 is in contact with the inner peripheral surface 94A of the outer cylinder portion 94 in the sleeve hub 86, thereby restricting the maximum movement in the clutch radial direction outward due to the centrifugal force. The inner peripheral surface 94A of the outer cylindrical portion 94 of the sleeve hub 86, which is the maximum movement restriction position of the centrifugal roller 88, is set to the outside in the clutch radial direction with respect to the inner peripheral surface 103A of the outer peripheral wall 103 of the clutch housing 87. . That is, the distance L from the axis O of the driven shaft 64 on the inner peripheral surface 94 A of the outer cylindrical portion 94 of the sleeve hub 86 is from the axis O of the driven shaft 64 on the inner peripheral surface 103 A of the outer peripheral wall 103 of the clutch housing 87. Is set to be larger than the distance M (L> M).

  With the configuration as described above, according to the present embodiment, the following effects (1) to (5) are obtained.

  (1) The maximum movement restriction position of the centrifugal roller 88 that moves outward in the clutch radial direction by centrifugal force is outside the sleeve hub 86 outside the inner peripheral surface 103A of the outer peripheral wall 103 of the clutch housing 87 in the clutch radial direction. Since the inner peripheral surface 94A of the cylindrical portion 94 is set, the centrifugal force acting on the centrifugal roller 88 can be increased. Accordingly, since the pressing force by which the centrifugal roller 88 presses the drive plate 90 and the driven plate 91 can be increased based on this centrifugal force, the power transmission torque by the clutch device 37 can be improved, and the clutch capacity of the clutch device 37 can be sufficiently secured. . As a result, it is not necessary to increase the outer diameter of the drive plate 90 and the driven plate 91 or increase the number of these plates 90 and 91 in order to improve the power transmission torque (ensure the clutch capacity). The size can be reduced and the cost can be reduced.

  (2) The drive plate 90 is supported by the inner cylindrical portion 93 of the sleeve hub 86 that is integrally rotated with the driven shaft 64, and the driven plate 91 is supported by the outer peripheral wall 103 of the clutch housing 87 that is integrally rotated with the first reduction gear 75A. Yes. For this reason, the driving force from the driven shaft 64 is transmitted to the first reduction gear 75A via the sleeve hub 86, the drive plate 90, the driven plate 91, and the clutch housing 87 by frictional joining between the drive plate 90 and the driven plate 91. Can do.

  (3) Since the outer peripheral wall 103 of the clutch housing 87 supports the driven plate 91, the dimension of the outer peripheral wall 103 is determined by the outer diameter of the driven plate 91. Therefore, if the centrifugal roller 88 is disposed in the clutch housing 87 and the maximum movement restricting member of the centrifugal roller 88 outward in the clutch radial direction is the inner peripheral surface 103A of the outer peripheral wall 103, the clutch radial of the centrifugal roller 88 is The maximum amount of movement outward in the direction is restricted by the outer diameter of the driven plate 91.

  On the other hand, in this embodiment, the centrifugal roller 88 is disposed in the space 109 surrounded by the inner cylindrical portion 93 and the outer cylindrical portion 94 of the sleeve hub 86 and the drive plate 90B. The maximum outward movement restricting member can be the inner peripheral surface 94 </ b> A of the outer cylindrical portion 94 of the sleeve hub 86. Since the outer cylindrical portion 94 of the sleeve hub 86 is not affected by the outer diameters of the drive plate 90 and the driven plate 91, the centrifugal roller 88 is made to move more than the inner peripheral surface 103 A of the outer peripheral wall 103 of the clutch housing 87 in the clutch radial direction. It can be moved outward. As a result, the centrifugal force acting on the centrifugal roller 88 can be increased, and the power transmission torque can be improved as described in the effect (1).

  (4) An urging spring 89 interposed between the drive plate 90B and the drive plate 90C is disposed between the inner cylindrical portion 93 of the sleeve hub 86 and the driven plate 91 in the clutch radial direction. When the clutch device 37 is in the clutch-off state (the upper half of FIG. 3), the urging spring 89 is in a position that partially overlaps the centrifugal roller 88 in the clutch radial direction. For this reason, further downsizing of the clutch device 37 in the clutch radial direction can be realized.

  (5) The clutch device 37 is a wet multi-plate clutch, and the drive plate 90 and the driven plate 91 housed in the clutch housing 87 are in an atmosphere in which lubricating oil exists. Therefore, particularly in the clutch-in state in which the drive plate 90 and the driven plate 91 are frictionally joined, the volume of the clutch device 37 can be reduced, and the cooling performance of the drive plate 90 and the driven plate 91 can be improved. Can do.

  As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this, A various deformation | transformation can be made in the range which does not deviate from the main point of this invention.

37 Clutch device (Multi-plate automatic centrifugal clutch device)
54 Crankshaft 64 Driven shaft (input unit)
75A 1st reduction gear (output unit)
86 Sleeve hub 87 Clutch housing 88 Centrifugal roller 89 Biasing spring 90 Drive plate 91 Driven plate 93 Inner cylinder part (cylindrical part) of sleeve hub
94 Outer cylinder portion 94A of sleeve hub Inner peripheral surface 103 of outer cylinder portion Outer peripheral wall 103A of clutch housing Inner peripheral surface 109 of outer peripheral wall Space L, M Distance

Claims (4)

A plurality of drive plates that rotate together on the input side,
A plurality of driven plates that are integrally rotated on the output side,
A clutch housing that accommodates these drive plates and driven plates on the inside in an alternating manner;
A centrifugal roller that presses the drive plate and the driven plate and frictionally joins with the action of centrifugal force generated by the rotation of the input unit;
In the multi-plate automatic centrifugal clutch device that transmits power from the input unit to the output unit by frictional bonding between the drive plate and the driven plate,
A sleeve hub that is rotatable and integrated with the input portion is provided, and a centrifugal roller restricting portion that restricts movement of the centrifugal roller in the clutch radial direction is formed on an outer cylindrical portion of the sleeve hub, and an inner cylindrical portion of the sleeve hub. The drive plate is supported by
Further, the clutch housing is provided integrally with the output portion, and the driven plate is supported by an outer peripheral wall of the clutch housing,
The multi-plate type automatic centrifuge characterized in that the maximum movement restriction position of the centrifugal roller that moves in the clutch radial direction by the centrifugal force is set to the outside in the clutch radial direction with respect to the inner peripheral surface of the outer peripheral wall of the clutch housing. Clutch device. The multi-plate automatic centrifugal clutch device according to claim 1 , wherein a centrifugal roller is disposed in a space surrounded by the sleeve hub and the drive plate. A biasing member generates a biasing force against a pressing force that presses the drive plate and the driven plate in the clutch thrust direction based on the centrifugal force acting on the centrifugal roller, and this biasing member is the driven member in the clutch radial direction. 2. The multi-plate automatic centrifugal clutch device according to claim 1 , wherein the multi-plate automatic centrifugal clutch device is disposed between the plate and the sleeve hub. The multi-plate automatic centrifugal clutch device according to claim 1, wherein the drive plate and the driven plate housed in the clutch housing are wet clutches in an atmosphere in which oil exists.

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