Continuously variable transmission, and, saddle riding type vehicle having continuously variable transmission

Abstract

To improve the manufacturability of supporting structure and the assemblability of the supporting structure, in a continuously variable transmission and a saddle riding type vehicle having a continuously variable transmission.SOLUTION: A continuously variable transmission 15 of a saddle riding type vehicle 1 comprises a primary pulley 41, a secondary pulley 42, a belt 43, a case 48, and a supporting structure 100. The supporting structure 100 is provided between at least one of the case 48 and the primary pulley 41, and the secondary pulley 42. The supporting structure 100 has a shaft member 46, a diametrically enlarged member 101, a first bearing 95, and an impregnated bush. The diametrically enlarged member 101 is disposed on the outer peripheral surface of a distal end portion 46b of the shaft member 46. The first bearing 95 is mounted to the case 48. The first bearing 95 is disposed at position away from the diametrically enlarged member 101 at an interval between the first bearing 95 and the diametrically enlarged member 101 in a radial direction. The impregnated bush 102 is disposed between the diametrically enlarged member 101 and the first bearing 95 in the radial direction.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a continuously variable transmission and a straddle-type vehicle having a continuously variable transmission. [Background technology]

[0002] Patent Document 1 discloses a support structure for a continuously variable transmission. This support structure supports a shaft with a bearing. In this support structure, an annular member is disposed on the outer peripheral surface of the tip of the shaft. The bearing is disposed on the outer peripheral surface of the annular member. A grease groove is formed on the outer peripheral surface of the annular member. Grease is disposed in the grease groove. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-68693 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional support structures, grease grooves are formed on the outer peripheral surface of the annular member to reduce sliding resistance between the bearing and the annular member. In this case, the outer peripheral surface of the annular member must be machined, which may reduce the manufacturability of the support structure. In addition, grease must be placed in the grease groove when assembling the support structure, which may reduce the ease of assembly of the support structure.

[0005] An object of the present invention is to provide a continuously variable transmission and a saddle-type vehicle having a continuously variable transmission that can improve the manufacturability and assembly efficiency of the support structure. [Means for solving the problem]

[0006] A continuously variable transmission according to one aspect of the present invention transmits driving force from an engine to wheels. The continuously variable transmission includes a primary pulley, a secondary pulley, a belt, a case, and a support structure. The primary pulley is connected to the engine. The secondary pulley is connected to the wheels. The belt is wound around the primary and secondary pulleys. The case covers the primary pulley, the secondary pulley, and the belt.

[0007] The support structure is provided between at least one of the primary pulley and the secondary pulley and the case. The support structure has a shaft member, a diameter expansion member, a first bearing, and an impregnated bushing. The shaft member includes a central rotation axis. The diameter expansion member is disposed on the outer peripheral surface of the tip end of the shaft member. The first bearing is attached to the case. The first bearing is disposed at a distance from the diameter expansion member in the radial direction relative to the central rotation axis. The impregnated bushing is disposed between the diameter expansion member and the first bearing in the radial direction.

[0008] In this continuously variable transmission, the tip end of the shaft member is supported by the first bearing via the diameter expansion member. That is, the shaft diameter of the tip end of the shaft member can be increased by the diameter expansion member. Therefore, in this continuously variable transmission, the surface pressure resistance of the supported surface supported by the first bearing can be improved compared to when the first bearing directly supports the tip end of the shaft member.

[0009] Furthermore, in this continuously variable transmission, an impregnated bushing is disposed between the diameter expansion member and the first bearing. This configuration reduces the sliding resistance between the first bearing and the diameter expansion member without machining the diameter expansion member. In other words, in this continuously variable transmission, the manufacturability and assembly of the support structure can be improved.

[0010] The continuously variable transmission may be configured as follows: The diameter expansion member is attached to the outer peripheral surface of the tip end of the shaft member. With this configuration, the tip end of the shaft member can be supported by the first bearing via the diameter expansion member and the impregnated bushing.

[0011] The continuously variable transmission may be configured as follows: The impregnated bushing is attached to the inner circumferential surface of the first bearing. With this configuration, the impregnated bushing can be easily disposed between the first bearing and the diameter expansion member.

[0012] The continuously variable transmission may be configured as follows: the shaft member has a shaft body and a tip end portion extending from the shaft body in an axial direction relative to the central axis of rotation; the outer diameter of the tip end portion of the shaft member is smaller than the outer diameter of the shaft body of the shaft member; this configuration makes it easy to position the diameter expansion member at the tip end portion of the shaft member.

[0013] The continuously variable transmission may further include a second bearing disposed on an outer peripheral surface of a tip end portion of the shaft member. The diameter expansion member is disposed on an outer peripheral surface on the tip end side of the tip end portion of the shaft member. The second bearing is disposed on an outer peripheral surface on the base end side of the tip end portion of the shaft member. The inner diameter of the first bearing is larger than the inner diameter of the second bearing.

[0014] In this case, the diameter expansion member is positioned further distally than the second bearing. Specifically, the impregnated bushing is positioned radially outward from the diameter expansion member, and the first bearing is positioned radially outward from the diameter expansion member, so the first bearing, the impregnated bushing, and the diameter expansion member are positioned further distally than the second bearing. In this state, the inner diameter of the first bearing is larger than the inner diameter of the second bearing. With this configuration, the distal end of the shaft member can be stably supported by the first bearing.

[0015] The continuously variable transmission may be configured as follows: The distal end portion of the shaft member has a first distal end portion that forms the outer peripheral surface of the distal end side, and a second distal end portion that forms the outer peripheral surface of the proximal end side, and the outer diameter of the first distal end portion is smaller than the outer diameter of the second distal end portion.

[0016] In this case, the first bearing is disposed at the first tip portion via the diameter expansion member and the impregnated bushing. The second bearing is disposed at the second tip portion. In this state, the outer diameter of the first tip portion is smaller than the outer diameter of the second tip portion. With this configuration, after disposing the second bearing at the second tip portion, the diameter expansion member, the impregnated bushing, and the first bearing can be easily disposed at the first tip portion.

[0017] The continuously variable transmission may be configured as follows: The inner diameter of the impregnated bushing is larger than the inner diameter of the second bearing. This configuration makes it possible to suitably reduce the sliding resistance between the first bearing and the diameter expansion member.

[0018] The continuously variable transmission may be configured as follows: A positioning member for positioning the diameter expansion member relative to the second bearing is disposed between the diameter expansion member and the second bearing in the axial direction relative to the central rotation axis. With this configuration, the position of the diameter expansion member relative to the second bearing can be stably maintained by the positioning member.

[0019] A saddle-type vehicle according to one aspect of the present invention includes an engine, wheels, and a continuously variable transmission. The engine includes a crankshaft. The continuously variable transmission transmits driving force from the engine to the wheels.

[0020] The continuously variable transmission has a primary pulley, a secondary pulley, a belt, a case, and a support structure. The primary pulley is connected to a crankshaft. The secondary pulley is connected to a wheel, and a belt is wound around the primary and secondary pulleys. The case covers the primary and secondary pulleys and the belt. The support structure is provided between the case and at least one of the primary and secondary pulleys.

[0021] The support structure includes a shaft member, a diameter expansion member, a first bearing, and an impregnated bushing. The shaft member includes a central rotation axis. The diameter expansion member is disposed on the outer peripheral surface of the tip end of the shaft member. The first bearing is attached to the case. The first bearing is disposed at a distance from the diameter expansion member in the radial direction relative to the central rotation axis. The impregnated bushing is disposed between the diameter expansion member and the first bearing in the radial direction.

[0022] In this saddle-ride type vehicle, in the support structure for the continuously variable transmission, an impregnated bushing is disposed between the diameter expansion member and the first bearing. This configuration makes it possible to reduce sliding resistance between the first bearing and the diameter expansion member without machining the diameter expansion member. In other words, in this saddle-ride type vehicle, the manufacturability and assembly of the support structure can be improved. [Effects of the Invention]

[0023] According to the present invention, it is possible to improve the manufacturability and assembly efficiency of a support structure in a continuously variable transmission and a saddle-ride type vehicle having a continuously variable transmission. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 2 is a left side view of the saddle-ride type vehicle. [Figure 2] FIG. 2 is a cross-sectional top view of the engine unit. [Figure 3] FIG. 2 is an enlarged view showing a primary pulley and a sheave drive mechanism. [Figure 4] FIG. 2 is an enlarged view showing a primary pulley and a sheave drive mechanism. [Figure 5] FIG. 2 is an enlarged view showing a secondary pulley and a centrifugal clutch. [Figure 6] FIG. 2 is an enlarged view showing a secondary pulley and a centrifugal clutch. [Figure 7] FIG. [Figure 8] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0025] A saddle-riding vehicle according to an embodiment will now be described with reference to the drawings. Fig. 1 is a left side view of a saddle-riding vehicle 1 according to an embodiment. The saddle-riding vehicle 1 according to this embodiment is a scooter. As shown in Fig. 1, the saddle-riding vehicle 1 includes a body frame 2, a body cover 3, a front wheel 4 and a rear wheel 5, a steering device 6, a seat 7, and an engine unit 8. In this embodiment, the front-rear and left-right directions correspond to the front-rear and left-right directions as seen from a rider seated on the seat 7.

[0026] The body cover 3 covers the body frame 2. The front wheel 4 is attached to a front fork 11. The rear wheel 5 is attached to an engine unit 8. The steering device 6 is supported by the body frame 2 so as to be rotatable left and right. The steering device 6 includes the front fork 11, a steering shaft 12, and a handle member 13.

[0027] The front fork 11 rotatably supports the front wheel 4. The steering shaft 12 is connected to the front fork 11. The steering shaft 12 is supported by the body frame 2 so as to be rotatable left and right. The handle member 13 is connected to the steering shaft 12. The seat 7 is disposed behind the handle member 13.

[0028] The engine unit 8 is disposed below the seat 7. The engine unit 8 is supported by the body frame 2 so as to be able to swing up and down. The rear wheel 5 is rotatably supported by the engine unit 8. The engine unit 8 includes an engine 14 and a continuously variable transmission 15 (an example of a continuously variable transmission). The continuously variable transmission 15 is disposed to the side of the engine 14. The continuously variable transmission 15 transmits driving force from the engine 14 to the rear wheel 5 (an example of a wheel).

[0029] 2 is a cross-sectional top view of the engine unit 8. As shown in FIG. 2, the engine 14 includes a crankcase 21, a crankshaft 22, a cylinder body 23, a cylinder head 24, a piston 25, a connecting rod 26, and a valve train 27.

[0030] The crankshaft 22 is housed in the crankcase 21. The crankshaft 22 is rotatably supported in the crankcase 21 via bearings 28 and 29. The crankshaft 22 includes a first shaft end 22A and a second shaft end 22B. The continuously variable transmission 15 is connected to the first shaft end 22A. The generator 31 is connected to the second shaft end 22B.

[0031] The cylinder body 23 is connected to the crankcase 21. The cylinder head 24 is connected to the cylinder body 23. A connecting rod 26 and a piston 25 are disposed in the cylinder body 23. The piston 25 is connected to the crankshaft 22 via the connecting rod 26. An ignition device 32 is attached to the cylinder head 24.

[0032] The valve mechanism 27 includes a camshaft 33. A cam chain 34 is wound around the camshaft 33 and the crankshaft 22. The rotation of the crankshaft 22 is transmitted to the camshaft 33 via the cam chain 34, causing the camshaft 33 to rotate. As a result, the intake valves and exhaust valves (not shown) of the engine 14 are driven by the valve mechanism 27.

[0033] 2 is an electronically controlled transmission, that is, continuously variable transmission 15 is electrically controlled to change the gear ratio in response to a command signal from a controller (not shown).

[0034] As shown in FIG. 2, the continuously variable transmission 15 has a primary pulley 41, a secondary pulley 42, a belt 43, a sheave drive mechanism 44, a centrifugal clutch 45, an output shaft 46 (an example of a shaft member), a reducer 47, and a transmission case 48 (an example of a case).

[0035] The primary pulley 41 is connected to the engine 14. Specifically, the primary pulley 41 is connected to the crankshaft 22. The primary pulley 41 includes a V-shaped first groove 41A. The secondary pulley 42 is connected to the rear wheel 5 via the axle 49. Specifically, the secondary pulley 42 is connected to the rear wheel 5 via the output shaft 46, the reducer 47, and the axle 49. The secondary pulley 42 includes a V-shaped second groove 42A.

[0036] The belt 43 is wound around the primary pulley 41 and the secondary pulley 42. The belt 43 has a trapezoidal cross section corresponding to the shapes of the first groove 41A and the second groove 42A. The secondary pulley 42 is connected to an output shaft 46 via a centrifugal clutch 45.

[0037] The output shaft 46 is rotatably supported by the reducer case 51 via bearings 53 and 54. The output shaft 46 is connected to an axle 49 via a reducer 47. The axle 49 is rotatably supported by the reducer case 51 via bearings 55 and 56.

[0038] The reducer 47 includes a reducer case 51 and a gear 52. The reducer case 51 houses the gear 52. The gear 52 transmits the rotation of the output shaft 46 to the axle 49. Note that in FIG. 2, only the gear 52 out of the multiple gears of the reducer 47 is shown, and the other gears are omitted.

[0039] The transmission case 48 covers the primary pulley 41, secondary pulley 42, belt 43, centrifugal clutch 45, and output shaft 46 from the outside in the axial direction. The transmission case 48 is attached to the reducer case 51 and crankcase 21. <Is it okay to attach the transmission case 48 to the reducer case 51? Thank you for your confirmation.> Fig. 3 is an enlarged view showing the primary pulley 41 and the sheave drive mechanism 44. As shown in Fig. 3, the primary pulley 41 includes a first movable sheave 57 and a first fixed sheave 58. The first movable sheave 57 is supported on the crankshaft 22 so as to be movable in the axial direction of the crankshaft 22. The first movable sheave 57 is disposed axially inward (on the left side in Fig. 3) of the first fixed sheave 58.

[0040] The first movable sheave 57 is supported on the crankshaft 22 so as to be unrotatable in the circumferential direction of the crankshaft 22. The first movable sheave 57 is fixed to the crankshaft 22 so as to rotate integrally with the crankshaft 22.

[0041] The first movable sheave 57 includes a first sheave portion 59 and a first boss portion 60. The first sheave portion 59 is disposed opposite the first fixed sheave 58 in the axial direction of the crankshaft 22. A first groove 41A is provided between the first sheave portion 59 and the first fixed sheave 58.

[0042] The first boss portion 60 extends from the first sheave portion 59 in the axial direction of the crankshaft 22. The first boss portion 60 includes a first boss hole 61. The first boss hole 61 extends so as to penetrate the first boss portion 60 in the axial direction of the crankshaft 22. The crankshaft 22 is inserted into the first boss hole 61.

[0043] The crankshaft 22 includes an outer shaft 62. The outer shaft 62 is attached to the outer peripheral surface of the first shaft end 22A of the crankshaft 22. The first movable sheave 57 described above is fixed to the outer shaft 62 by spline engagement. The outer shaft 62 is disposed in the first boss hole 61.

[0044] A first bushing 63 and a second bushing 64 are press-fitted into the first boss hole 61. The first bushing 63 and the second bushing 64 are disposed between the first boss hole 61 and the outer peripheral surface of the outer shaft 62. The first bushing 63 and the second bushing 64 are formed from a sliding material.

[0045] As the first movable sheave 57 moves in the axial direction of the crankshaft 22, the first bushing 63 and the second bushing 64 slide in the axial direction relative to the outer shaft 62. A lubricant such as grease is filled in the first boss hole 61. The gap between the first boss portion 60 and the outer shaft 62 is sealed by oil seals 65, 66.

[0046] The first fixed sheave 58 is fixed to the crankshaft 22. The first fixed sheave 58 is fixed to the crankshaft 22 by a nut 40. The first fixed sheave 58 is fixed to the crankshaft 22 so as to be immovable in the axial direction. The first fixed sheave 58 is fixed to the crankshaft 22 so as to rotate integrally with the crankshaft 22.

[0047] The sheave drive mechanism 44 axially moves the first movable sheave 57. As shown in Figure 2, the sheave drive mechanism 44 includes an electric actuator 67, a first drive member 68, and a second drive member 69.

[0048] The electric actuator 67 is, for example, an electric motor. The electric actuator 67 may be an actuator other than an electric motor. The electric actuator 67 includes a rotating shaft 70. The rotating shaft 70 is connected to a first driving member 68 via a gear 71. The rotation of the rotating shaft 70 is transmitted to the first driving member 68 via the gear 71.

[0049] 3 and 4, the first drive member 68 includes a first hole 72. The first hole 72 extends through the first drive member 68 in the axial direction of the crankshaft 22. The crankshaft 22 is inserted through the first hole 72. The first drive member 68 is rotatably supported on the crankshaft 22 via a bearing 50. The first drive member 68 is supported so as to be immovable relative to the crankshaft 22 in the axial direction of the crankshaft 22.

[0050] The first driving member 68 includes a gear portion 73 and a feed screw portion 74. The gear portion 73 extends from the feed screw portion 74 in the radial direction of the crankshaft 22. The gear portion 73 meshes with the gear 71. The rotation of the rotating shaft 70 of the electric actuator 67 is transmitted to the gear portion 73 via the gear 71. This causes the first driving member 68 to rotate. The feed screw portion 74 extends from the gear portion 73 in the axial direction of the crankshaft 22. A first screw 75 is provided on the outer peripheral surface of the feed screw portion 74.

[0051] A crankcase cover 76 is attached to the crankcase 21. The crankcase cover 76 includes an opening 76A. The opening 76A opens to the primary pulley 41 side. The second driving member 69 is inserted through the opening 76A of the crankcase 21. An oil seal 77 seals the gap between the second driving member 69 and the crankcase cover 76.

[0052] The second driving member 69 includes a second hole 78. The second hole 78 extends so as to penetrate the second driving member 69 in the axial direction of the crankshaft 22. The crankshaft 22 and the first boss portion 60 are inserted through the second hole 78.

[0053] The second drive member 69 is rotatably supported by the first boss portion 60. The second drive member 69 is supported by the first boss portion 60 via a bearing 79. The second drive member 69 is supported by the first boss portion 60 so as to be immovable in the axial direction. The second drive member 69 moves in the axial direction integrally with the first movable sheave 57. The gap between the second drive member 69 and the first boss portion 60 is sealed by an oil seal 80.

[0054] A second screw 81 is provided on the inner peripheral surface of the second driving member 69. The second screw 81 meshes with the first screw 75 of the first driving member 68. When the first driving member 68 rotates, the second driving member 69 moves in the axial direction, as shown in FIG. 4. This causes the first movable sheave 57 to move in the axial direction.

[0055] 5 and 6 are enlarged views showing the secondary pulley 42 and the centrifugal clutch 45. As shown in Fig. 5 and 6, the secondary pulley 42 includes a second fixed sheave 82 and a second movable sheave 83. The second fixed sheave 82 is supported rotatably on the output shaft 46. The second fixed sheave 82 is supported immovably in the axial direction on the output shaft 46.

[0056] The second fixed sheave 82 is disposed opposite the second movable sheave 83 in the axial direction of the output shaft 46. The second fixed sheave 82 includes a second sheave portion 84 and a second boss portion 85. A second groove 42A is provided between the second sheave portion 84 and the second movable sheave 83.

[0057] The second boss portion 85 extends from the second sheave portion 84 in the axial direction of the output shaft 46. The second boss portion 85 includes a second boss hole 86. The second boss hole 86 extends so as to penetrate the second boss portion 85 in the axial direction of the output shaft 46. The output shaft 46 is inserted into the second boss hole 86.

[0058] As shown in Figures 5 and 6, the output shaft 46 is rotatably supported relative to the transmission case 48 via a bearing 95. A bushing 91 is press-fitted into the second boss hole 86. The bushing 91 is made of a sliding material. The bushing 91 is disposed between the second boss hole 86 and the outer peripheral surface of the output shaft 46. The output shaft 46 and the bearing 95 constitute a support structure 100, which will be described later.

[0059] A bearing 92 (an example of a second bearing) is disposed in the second boss hole 86. The bearing 92 is disposed on the outer peripheral surface of the tip portion of the output shaft 46. In detail, the bearing 92 is disposed on the outer peripheral surface of the base end side of the tip portion of the output shaft 46.

[0060] The second boss portion 85 is rotatably supported on the output shaft 46 by a bushing 91 and a bearing 92. The bushing 91 and the bearing 92 support the second fixed sheave 82. The bushing 91 and the bearing 92 support the second movable sheave 83 via the second boss portion 85. The second boss hole 86 is filled with a lubricant such as grease. An oil seal 93 seals the gap between the second boss portion 85 and the output shaft 46.

[0061] 5 and 6, the second movable sheave 83 is disposed axially opposite the second fixed sheave 82. The second movable sheave 83 is disposed axially outward (to the right in FIGS. 5 and 6) from the second fixed sheave 82.

[0062] The second movable sheave 83 is configured to rotate around the central rotation axis C. In detail, the second movable sheave 83 is supported non-rotatably with respect to the second boss portion 85. The second movable sheave 83 rotates integrally with the second sheave portion 84 via the second boss portion 85. In other words, the second movable sheave 83 rotates integrally with the second fixed sheave 82.

[0063] The second movable sheave 83 is configured to move in the axial direction relative to the second fixed sheave 82. Specifically, the second movable sheave 83 is configured to move in the axial direction relative to the second sheave portion 84. More specifically, the second movable sheave 83 is supported by the second boss portion 85 so as to be movable in the axial direction.

[0064] In this embodiment, the second movable sheave 83 is fixed to the second boss portion 85 by spline engagement. A spring 87 is disposed between the second movable sheave 83 and the centrifugal clutch 45. The spring 87 biases the second movable sheave 83 toward the second fixed sheave 82.

[0065] As shown in Fig. 5, when the vehicle speed is lower than a predetermined coupling speed, the centrifugal clutch 45 is in a disengaged state that disconnects the continuously variable transmission 15 from the rear wheels 5. As shown in Fig. 6, when the vehicle speed is equal to or higher than the coupling speed, the centrifugal clutch 45 is in an engaged state that connects the continuously variable transmission 15 to the rear wheels 5.

[0066] 5 and 6, the centrifugal clutch 45 includes a drive plate 88, a clutch shoe 89, and a clutch outer 90. The drive plate 88 is fixed to the second boss portion 85. The drive plate 88 rotates integrally with the second boss portion 85.

[0067] The clutch shoe 89 is connected to the drive plate 88. The clutch shoe 89 rotates integrally with the drive plate 88. The clutch shoe 89 is supported so as to be movable in the radial direction relative to the drive plate 88. The clutch shoe 89 is biased radially inward by a clutch spring (not shown).

[0068] The clutch outer 90 radially covers the clutch shoes 89. The clutch outer 90 is attached to the output shaft 46 so as to rotate integrally with the output shaft 46. The clutch outer 90 is positioned on the output shaft 46 by a nut 94.

[0069] When the vehicle speed is slower than a predetermined connection speed, the clutch shoe 89 moves radially inward due to the biasing force of the clutch spring, and separates from the clutch outer 90. In this state, the centrifugal clutch 45 is in a disengaged state, and the rotation of the secondary pulley 42 is not transmitted to the output shaft 46.

[0070] When the vehicle speed is equal to or higher than the engagement speed, the clutch shoes 89 move radially outward due to centrifugal force against the biasing force of the clutch spring. As a result, the clutch shoes 89 come into contact with the clutch outer 90. In this state, the centrifugal clutch 45 is engaged, and the rotation of the secondary pulley 42 is transmitted to the output shaft 46 via the drive plate 88, the clutch shoes 89, and the clutch outer 90.

[0071] 2, 5, and 6, the continuously variable transmission 15 further includes a support structure 100. The support structure 100 is provided between the transmission case 48 and at least one of the primary pulley 41 and the secondary pulley 42.

[0072] 5 and 6, in this embodiment, the support structure 100 is provided between the secondary pulley 42 and the transmission case 48. In the case where the tip end of the crankshaft 22 is supported by a case member, the support structure 100 may be provided between the primary pulley 41 and the case member.

[0073] 7 and 8, the support structure 100 includes the output shaft 46 described above, a diameter expansion member 101, the bearing 95 described above (an example of a first bearing), and an impregnated bushing 102. In the following description, the axial direction of the output shaft 46 will be referred to as the "axial direction," and the radial direction of the output shaft 46 will be referred to as the "radial direction." The output shaft 46 includes a central rotation axis C. The axial direction is the direction in which the central rotation axis C extends. The radial direction is the direction perpendicular to the central rotation axis C and away from the central rotation axis C.

[0074] 7 and 8, the output shaft 46 extends in the axial direction. The output shaft 46 is formed in a shaft shape. As shown in Fig. 7 and 8, the output shaft 46 has a shaft body 46a and a tip end portion 46b.

[0075] 2, shaft body 46a is rotatably supported by reducer case 51 via bearings 53 and 54. As shown in FIGS. 5, 6, and 7, tip end portion 46b is rotatably supported by transmission case 48 via bearing 95.

[0076] 7 and 8, the tip end portion 46b extends axially from the shaft body 46a. The outer diameter of the tip end portion 46b is smaller than the outer diameter of the shaft body 46a. As shown in FIG. 7, the tip end portion 46b is inserted into a hole 90a in a clutch outer 90.

[0077] 7 and 8, the tip portion 46b has a first tip portion 46b1 and a second tip portion 46b2. The first tip portion 46b1 forms the outer peripheral surface on the tip side. The outer diameter of the first tip portion 46b1 is smaller than the outer diameter of the shaft body 46a. The outer diameter of the first tip portion 46b1 is smaller than the outer diameter of the second tip portion 46b2.

[0078] Second tip portion 46b2 forms the outer peripheral surface on the base end side. Second tip portion 46b2 is disposed axially between shaft body 46a and first tip portion 46b1. The outer diameter of second tip portion 46b2 is smaller than the outer diameter of the shaft body. The outer diameter of second tip portion 46b2 is larger than the outer diameter of first tip portion 46b1.

[0079] As shown in Fig. 7, a bearing 92 is disposed on the outer peripheral surface of the second tip portion 46b2. The bearing 92 rotatably supports the second boss portion 85 with respect to the output shaft 46. In detail, as shown in Figs. 7 and 8, the bearing 92 has an inner ring 92a, an outer ring 92b disposed radially outward of the inner ring 92a, and a plurality of rolling elements 92c disposed between the inner ring 92a and the outer ring 92b.

[0080] 7, an inner ring 92a of the bearing 92 is attached to the outer peripheral surface of the second tip portion 46b2. An outer ring 92b of the bearing 92 contacts the second boss hole 86 of the second boss portion 85 so as to rotate integrally with the second boss portion 85. The inner ring 92a of the bearing 92 abuts against a step 46c formed between the shaft body 46a and the second tip portion 46b2. This restricts axial movement of the bearing 92 toward the engine 14.

[0081] The diameter expansion member 101 is used to expand the outer diameter of the output shaft 46. As shown in FIG. 8, the diameter expansion member 101 is formed in a cylindrical shape. The diameter expansion member 101 may be formed in a cylindrical shape with a C-shaped cross section. As shown in FIG. 7, the diameter expansion member 101 is disposed on the outer peripheral surface of the tip end portion 46b of the output shaft 46. In detail, the diameter expansion member 101 is disposed on the outer peripheral surface on the tip side of the tip end portion 46b.

[0082] In this embodiment, the diameter expansion member 101 is attached to the outer peripheral surface of the first tip portion 46b1. In this state, the outer diameter of the diameter expansion member 101 is larger than the outer diameter of the shaft body 46a. The outer diameter of the diameter expansion member 101 is larger than the outer diameter of a positioning member 103, which will be described later. The diameter expansion member 101 abuts against the outer surface of the clutch outer 90 in the axial direction.

[0083] As shown in Fig. 7, a positioning member 103 is disposed axially between the diameter expansion member 101 and the bearing 92. The positioning member 103 axially positions the diameter expansion member 101 relative to the bearing 92. As shown in Fig. 8, the positioning member 103 is formed in a cylindrical shape.

[0084] 7, the positioning member 103 is disposed on the outer peripheral surface of the tip portion 46b. Specifically, the positioning member 103 is disposed on the outer peripheral surface of the second tip portion 46b2. In this embodiment, the positioning member 103 engages with the second tip portion 46b2 by spline engagement. This allows the positioning member 103 to rotate integrally with the output shaft 46.

[0085] The positioning member 103 is inserted into the hole 90a of the clutch outer 90 while abutting against the inner surface of the clutch outer 90 in the axial direction. The positioning member 103 is disposed radially between the hole 90a of the clutch outer 90 and the outer peripheral surface of the tip end portion 46b. In this embodiment, the positioning member 103 is disposed radially between the hole 90a of the clutch outer 90 and the second tip end portion 46b2.

[0086] The positioning member 103 and the diameter expansion member 101 hold the clutch outer 90 in the axial direction. In detail, the bearing 92, the positioning member 103, the clutch outer 90, and the diameter expansion member 101 are held in the axial direction by the step 46c and the nut 94. The bearing 92, the positioning member 103, and the nut 94 may be considered as components included in the support structure 100.

[0087] 7, the bearing 95 rotatably supports the output shaft 46 with respect to the transmission case 48. The bearing 95 is attached to the transmission case 48. More specifically, the bearing 95 is attached to a bulging portion 48a of the transmission case 48.

[0088] More specifically, the outer ring 95b of the bearing 95 is attached to the bulging portion 48a of the transmission case 48. The outer ring 95b of the bearing 95 is sandwiched between the bulging portion 48a and the retaining member 104. In this embodiment, as shown in FIG. 8 , the retaining member 104 is a C-ring. The retaining member 104 may also be considered as a component included in the support structure 100.

[0089] 7, the bearing 95 is disposed radially outward of the diameter expansion member 101. The bearing 95 is disposed radially at a distance from the diameter expansion member 101. In detail, the bearing 95 has an inner ring 95a, an outer ring 95b disposed radially outward of the inner ring 95a, and a plurality of rolling elements 95c disposed between the inner ring 95a and the outer ring 95b.

[0090] The inner peripheral surface of the inner ring 95a of the bearing 95 is disposed at a distance from the outer peripheral surface of the diameter expansion member 101 in the radial direction. The inner diameter of the inner ring 95a of the bearing 95 is larger than the inner diameter of the inner ring 95a of the bearing 92. The inner diameter of the inner ring 95a of the bearing 95 is larger than the outer diameter of the outer ring 95b of the bearing 92.

[0091] As shown in Fig. 8, the impregnated bushing 102 is formed in an annular shape. As shown in Fig. 7, the impregnated bushing 102 is attached to the inner circumferential surface of the inner ring 95a of the bearing 95. The impregnated bushing 102 is disposed radially between the inner circumferential surface of the inner ring 95a of the bearing 95 and the outer circumferential surface of the diameter expansion member 101. The inner diameter of the impregnated bushing 102 is larger than the inner diameter of the bearing 92.

[0092] In the continuously variable transmission 15 described above, when the vehicle speed is equal to or higher than the coupling speed, the centrifugal clutch 45 is in the engaged state shown in Fig. 6. As a result, the rotation of the crankshaft 22 is transmitted to the rear wheel 5 via the primary pulley 41, the belt 43, the secondary pulley 42, the centrifugal clutch 45, the output shaft 46, the reducer 47, and the axle 49. This allows the saddle-type vehicle 1 to travel.

[0093] Furthermore, the gear ratio of the continuously variable transmission 15 is electrically controlled by moving the first movable sheave 57 with the sheave drive mechanism 44. The gear ratio of the continuously variable transmission 15 means the ratio of the rotational speed of the crankshaft 22 to the rotational speed of the output shaft 46.

[0094] More specifically, when the first driving member 68 is rotated in a certain direction by the electric actuator 67, the second driving member 69 moves outward in the axial direction, as shown in Fig. 4. This causes the first moving sheave 57 to move outward in the axial direction together with the second driving member 69. When the first moving sheave 57 moves outward in the axial direction, the width of the first groove 41A between the first moving sheave 57 and the first fixed sheave 58 becomes smaller.

[0095] As a result, the diameter of the portion of the belt 43 wound around the primary pulley 41 (hereinafter referred to as the first winding diameter) increases. When the first winding diameter increases, the diameter of the portion of the belt 43 wound around the secondary pulley 42 (hereinafter referred to as the second winding diameter) decreases. This reduces the gear ratio. In this case, as shown in FIG. 6, the second movable sheave 83 moves axially outward against the biasing force of the spring 87, and the width of the second groove 42A increases.

[0096] When the electric actuator 67 rotates the first drive member 68 in the reverse direction, the second drive member 69 moves axially inward, as shown in FIG. 3. As a result, the first movable sheave 57 moves axially inward together with the second drive member 69. When the first movable sheave 57 moves axially inward, the width of the first groove 41A between the first movable sheave 57 and the first fixed sheave 58 increases. This reduces the first winding diameter. When the first winding diameter decreases, the second winding diameter increases. This increases the gear ratio. In this case, as shown in FIG. 5, the second movable sheave 83 moves axially inward due to the biasing force of the spring 87, and the width of the second groove 42A decreases.

[0097] In the saddle-type vehicle 1 having the above-described configuration, in the continuously variable transmission 15, the tip end 46b of the output shaft 46 is supported by the bearing 95 via the diameter expansion member 101. That is, the shaft diameter of the tip end 46b of the output shaft 46 can be increased by the diameter expansion member 101. Therefore, in the continuously variable transmission 15, the surface pressure resistance of the supported surface supported by the bearing 95 can be improved compared to when the bearing 95 directly supports the tip end 46b of the output shaft 46.

[0098] Furthermore, in the continuously variable transmission 15, the impregnated bushing 102 is disposed between the diameter expansion member 101 and the bearing 95. This configuration makes it possible to reduce the sliding resistance between the bearing 95 and the diameter expansion member 101 without processing the diameter expansion member 101. That is, in the continuously variable transmission 15, it is possible to improve the manufacturability of the support structure 100 and the assembly of the support structure.

[0099] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention.

[0100] The straddle-type vehicle 1 is not limited to a scooter, but may be other types of vehicles such as a street type, an off-road type, or a moped. The configuration of the continuously variable transmission 15 is not limited to that of the above embodiment and may be modified. The process for controlling the gear ratio of the continuously variable transmission 15 is not limited to that of the above embodiment and may be modified. [Industrial Applicability]

[0101] According to the present invention, it is possible to improve the manufacturability and assembly efficiency of a support structure in a continuously variable transmission and a saddle-ride type vehicle having a continuously variable transmission. [Explanation of symbols]

[0102] 5: rear wheel, 14: engine, 15: continuously variable transmission, 22: crankshaft, 41: primary pulley, 42: secondary pulley, 43: belt, 46: output shaft, 46a: shaft body of output shaft, 46b: tip portion of output shaft, 46b1: first tip portion of output shaft, 46b2: second tip portion of output shaft, 48: transmission case, 92: bearing, 95: bearing, 100: support structure, 101: diameter expansion member, 102: impregnated bushing, 103: positioning member, C: rotation center axis

Claims

1. A continuously variable transmission that transmits driving force from an engine to wheels, a primary pulley connected to the engine; a secondary pulley connected to the wheel; a belt wound around the primary pulley and the secondary pulley; a case that covers the primary pulley, the secondary pulley, and the belt; a support structure provided between at least one of the primary pulley and the secondary pulley and the case; Equipped with The support structure includes: a shaft member including a central axis of rotation; an expanding member disposed on an outer peripheral surface of a tip end portion of the shaft member; a first bearing attached to the case and disposed at a distance from the diameter expansion member in a radial direction relative to the rotation center axis; an impregnated bushing disposed between the expansion member and the first bearing in the radial direction, Continuously variable transmission.

2. The diameter expanding member is attached to the outer peripheral surface of the tip end portion of the shaft member.

2. The continuously variable transmission according to claim 1.

3. The impregnated bushing is attached to the inner peripheral surface of the first bearing.

2. The continuously variable transmission according to claim 1.

4. the shaft member includes a shaft body and the tip portion extending from the shaft body in an axial direction relative to the central rotation axis, The outer diameter of the tip portion is formed to be smaller than the outer diameter of the shaft body.

2. The continuously variable transmission according to claim 1.

5. a second bearing disposed on the outer circumferential surface of the tip end portion of the shaft member; Furthermore, the diameter expansion member is disposed on an outer peripheral surface of the distal end side of the distal end portion of the shaft member, the second bearing is disposed on an outer peripheral surface of the distal end portion of the shaft member on a proximal end side, The inner diameter of the first bearing is larger than the inner diameter of the second bearing.

2. The continuously variable transmission according to claim 1.

6. the distal end portion has a first distal end portion that forms the outer peripheral surface on the distal end side and a second distal end portion that forms the outer peripheral surface on the base end side, The outer diameter of the first tip portion is smaller than the outer diameter of the second tip portion.

6. The continuously variable transmission according to claim 5.

7. The inner diameter of the impregnated bushing is larger than the inner diameter of the second bearing.

6. The continuously variable transmission according to claim 5.

8. a positioning member for positioning the diameter expansion member with respect to the second bearing, the positioning member being disposed between the diameter expansion member and the second bearing in an axial direction relative to the rotation central axis; 6. The continuously variable transmission according to claim 5.

9. an engine including a crankshaft; Wheels and a continuously variable transmission that transmits driving force from the engine to the wheels; Equipped with the continuously variable transmission includes a primary pulley connected to the crankshaft, a secondary pulley connected to the wheel, a belt wound around the primary pulley and the secondary pulley, a case covering the primary pulley, the secondary pulley, and the belt, and a support structure provided between at least one of the primary pulley and the secondary pulley and the case, The support structure includes: a shaft member including a central axis of rotation; an expanding member disposed on an outer peripheral surface of a tip end portion of the shaft member; a first bearing attached to the case and disposed at a distance from the diameter expansion member in a radial direction relative to the rotation center axis; an impregnated bushing disposed between the expansion member and the first bearing in the radial direction, Saddle-type vehicle.

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