Continuously variable transmission and saddle riding type vehicle with continuously variable transmission

Abstract

To improve the load resistant power of a movable sheave in an electronically controlled type continuously variable transmission.SOLUTION: A continuously variable transmission 15 is of an electronically controlled type. The continuously variable transmission 15 comprises a rotation shaft 22, a pair of bushings 63, 64, and a movable sheave 60. The pair of bushings 63, 64 are disposed to be slidable relative to the rotation shaft 22 in the axial direction of the rotation shaft 22. The movable sheave 60 includes a boss portion 60b disposed on the outer peripheral surface of each of the pair of bushings 63, 64, and is moved in the axial direction according to sliding of the pair of bushings 63, 64 in the axial direction. The pair of bushings 63, 64 are disposed on both ends of the inner peripheral surface of the boss portion 60b.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, continuously variable transmissions in which a belt is wound around a pair of pulleys have been known. The continuously variable transmission in Patent Document 1 is a centrifugal type, and the movable sheave is arranged so as to be non-rotatable relative to the rotating shaft but slidable in the axial direction. The movable sheave moves in the axial direction as the bush slides axially relative to the rotating shaft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-152884 Summary of the Invention [Problem to be solved by the invention]

[0004] In the continuously variable transmission of Patent Document 1, the offset load from the belt that the movable sheave receives is supported by a weight. In contrast, in an electronically controlled continuously variable transmission, the weight for supporting the offset load from the belt is omitted. For this reason, there is a demand for improving the load-bearing performance of the movable sheave in electronically controlled continuously variable transmissions.

[0005] An object of the present invention is to improve the load-bearing performance of a movable sheave in an electronically controlled continuously variable transmission. [Means for solving the problem]

[0006] A continuously variable transmission according to one aspect of the present invention is an electronically controlled continuously variable transmission. The continuously variable transmission includes a rotating shaft, a pair of bushings, and a movable sheave. The pair of bushings are arranged to be slidable in the axial direction of the rotating shaft relative to the rotating shaft. The movable sheave includes boss portions arranged on outer peripheral surfaces of the pair of bushings, and moves in the axial direction in response to the sliding of the pair of bushings in the axial direction. The pair of bushings are arranged on both ends of the inner peripheral surface of the boss portion.

[0007] In the continuously variable transmission of this embodiment, a pair of bushings arranged at both ends of the inner surface of the boss portion of the movable sheave can absorb the unbalanced load received from the belt of the continuously variable transmission, thereby improving the load-bearing capacity of the movable sheave.

[0008] The movable sheave may include a spline groove disposed on the inner peripheral surface of the boss portion. The rotating shaft may include spline teeth that are spline-fitted into the spline groove. The spline groove may have an axial dimension that is larger than the axial dimension of the spline teeth. In this case, the spline groove can be made to wrap in the radial direction of the rotating shaft within the range in which the pair of bushings slide on the rotating shaft, thereby preventing the axial dimension of the rotating shaft from becoming larger.

[0009] The spline teeth of the rotary shaft may be formed integrally with the rotary shaft, in which case the spline engagement between the spline teeth and the spline grooves is stable and the number of parts can be reduced.

[0010] A lubricant may be enclosed between the pair of bushings, which can improve the wear resistance of the pair of bushings, the rotating shaft, and the movable sheave.

[0011] The continuously variable transmission may further include a lubricant reservoir filled with lubricant. The rotating shaft may include a first shaft portion and a second shaft portion disposed on the outer peripheral surface of the first shaft portion. The lubricant reservoir may include a first reservoir portion disposed between the outer peripheral surface of the first shaft portion and the inner peripheral surface of the second shaft portion, a second reservoir portion disposed between the outer peripheral surface of the second shaft portion and the inner peripheral surface of the boss portion, and a connecting hole extending radially of the rotating shaft and connecting the first reservoir portion and the second reservoir portion. In this case, the range in which the lubricant is filled can be increased, and the lubricant can be more easily guided from the second reservoir portion to the first reservoir portion via the connecting hole during rotation of the rotating shaft, thereby further improving the wear resistance of the pair of bushings, the rotating shaft, and the movable sheave.

[0012] The second shaft portion may include spline teeth that are spline-fitted to the inner peripheral surface of the boss portion. The connection hole of the lubricant reservoir may be arranged side by side with the spline teeth in the circumferential direction of the rotating shaft. In this case, it is possible to prevent the axial dimension of the rotating shaft from increasing.

[0013] The boss portion of the movable sheave may include a spline groove that fits into the spline teeth. The spline groove may have an axial dimension that is larger than the axial dimension of the spline teeth. In this case, the axial dimension of the rotating shaft can be further prevented from increasing.

[0014] A saddle-ride type vehicle according to another aspect of the present invention includes the continuously variable transmission described above. In the saddle-ride type vehicle according to this aspect, the load-bearing capacity of the movable sheave can be improved. [Effects of the Invention]

[0015] According to the present invention, it is possible to improve the load-bearing performance of the movable sheave in an electronically controlled continuously variable transmission. [Brief explanation of the drawings]

[0016] [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. 4 is a partially enlarged view of FIG. [Figure 6] 4 is a cross-sectional view of the second shaft portion taken along line AA in FIG. 3. [Figure 7] FIG. 4 is an enlarged view showing a secondary pulley and a centrifugal clutch. [Figure 8] FIG. 4 is an enlarged view showing a secondary pulley and a centrifugal clutch. DETAILED DESCRIPTION OF THE INVENTION

[0017] 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, 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 refer to the front-rear and left-right directions as seen from a rider seated on the seat 7.

[0018] The body cover 3 covers the body frame 2. The steering device 6 is supported by the body frame 2 so as to be rotatable left and right. The steering device 6 includes a front fork 11, a steering shaft 12, and a handle member 13.

[0019] 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.

[0020] The seat 7 is disposed behind the handle member 13. 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 engine unit 8 rotatably supports the rear wheel 5. The engine unit 8 includes an engine 14 and a continuously variable transmission 15. 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.

[0021] Fig. 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 (an example of a rotating shaft), a cylinder body 23, a cylinder head 24, a piston 25, a connecting rod 26, and a valve train 27.

[0022] The crankshaft 22 is housed in the crankcase 21. The crankshaft 22 is rotatably supported by the crankcase 21 via bearings 28 and 29. The crankshaft 22 includes a first shaft end 22A and a second shaft end 22B. A continuously variable transmission 15 (an example of a continuously variable transmission) is connected to the first shaft end 22A. A generator 31 is connected to the second shaft end 22B.

[0023] 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 within 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. The valve train 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, intake valves and exhaust valves (not shown) of the engine 14 are driven by the valve train 27.

[0024] The continuously variable transmission 15 is an electronically controlled transmission, that is, the continuously variable transmission 15 is electrically controlled to change the gear ratio in response to a command signal from a controller (not shown).

[0025] As shown in FIG. 2, the continuously variable transmission 15 includes a crankshaft 22, a primary pulley 41, a secondary pulley 42, a belt 43, a sheave drive mechanism 44, a centrifugal clutch 45, an output shaft 46, a reducer 47, and a transmission case 48.

[0026] Primary pulley 41 is connected to crankshaft 22. Primary pulley 41 includes a V-shaped first groove 41A. Secondary pulley 42 is connected to rear wheel 5 via axle 49. Secondary pulley 42 includes a V-shaped second groove 42A.

[0027] 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. The output shaft 46 is connected to an axle 49 via a reducer 47. The output shaft 46 is rotatably supported by a reducer case 51 (described later) via bearings 53 and 54. The axle 49 is rotatably supported by the reducer case 51 via bearings 55 and 56.

[0028] 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.

[0029] The transmission case 48 axially covers the primary pulley 41, the secondary pulley 42, the belt 43, the centrifugal clutch 45, and the output shaft 46.

[0030] 3 and 4 are enlarged views showing the primary pulley 41 and the sheave drive mechanism 44. Fig. 5 is a partial enlarged view of Fig. 3. As shown in Figs. 3 and 4, the primary pulley 41 includes a first movable sheave 57 (an example of a movable sheave) and a first fixed sheave 58.

[0031] The first movable sheave 57 is supported so as to be movable in the axial direction of the crankshaft 22 (hereinafter simply referred to as 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.

[0032] The first moving sheave 57 is supported by the crankshaft 22 so as to be unable to rotate in the circumferential direction of the crankshaft 22. The first moving sheave 57 is fixed to the crankshaft 22 by a spline. The first moving sheave 57 rotates integrally with the crankshaft 22.

[0033] 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. The first sheave portion 59 is fixed to the outer peripheral surface of the first boss portion 60. A first groove 41A is provided between the first sheave portion 59 and the first fixed sheave 58. The first boss portion 60 extends in the axial direction from the first sheave portion 59. As shown in FIG. 5 , the first boss portion 60 includes a first boss hole 60a and a spline groove 60b. The first boss hole 60a extends in the axial direction. The crankshaft 22 extends through the first boss hole 60a. The spline groove 60b is disposed on the inner peripheral surface of the first boss portion 60. The spline groove 60b is formed in the first boss hole 60a. The spline groove 60b extends in the axial direction along the first boss hole 60a.

[0034] The crankshaft 22 includes a first shaft portion 22a, a second shaft portion 22b, and spline teeth 22c. The first shaft portion 22a is rotatably supported by the crankcase 21 via bearings 28 and 29.

[0035] Figure 6 is a cross-sectional view of the second shaft portion 22b taken along line AA in Figure 3. The second shaft portion 22b is formed in a cylindrical shape. The second shaft portion 22b is disposed on the outer peripheral surface of the first shaft portion 22a at the first shaft end 22A. The second shaft portion 22b extends through the first boss hole 60a.

[0036] The spline teeth 22c are spline-fitted into the spline grooves 60b. The spline teeth 22c extend in the axial direction. The spline teeth 22c are arranged on the outer peripheral surface of the second shaft portion 22b. As shown in FIG. 6, the spline teeth 22c protrude radially outward from the outer peripheral surface of the second shaft portion 22b. As shown in FIG. 5, the axial dimension of the spline teeth 22c is smaller than the axial dimension of the spline grooves 60b. That is, the axial dimension of the spline grooves 60b is larger than the axial dimension of the spline teeth 22c. The spline teeth 22c are formed integrally with the crankshaft 22. In this embodiment, the spline teeth 22c are formed integrally with the second shaft portion 22b. The spline teeth 22c and the spline grooves 60b are arranged between a pair of bushings 63, 64, which will be described later.

[0037] 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 be imrotatable relative to the crankshaft 22. The first fixed sheave 58 rotates integrally with the crankshaft 22.

[0038] The primary pulley 41 includes a pair of bushings 63, 64. The pair of bushings 63, 64 are arranged on both ends of the inner circumferential surface of the first boss portion 60. The pair of bushings 63, 64 are press-fitted into the first boss portion 60. The pair of bushings 63, 64 are formed of a sliding material. The inner circumferential surfaces of the pair of bushings 63, 64 are each coated with DLC. The pair of bushings 63, 64 are arranged between the inner circumferential surface of the first boss hole 60a and the outer circumferential surface of the second shaft portion 22b. As the first movable sheave 57 moves in the axial direction, the pair of bushings 63, 64 slide in the axial direction relative to the second shaft portion 22b. A lubricant such as grease is sealed between the pair of bushings 63, 64. The gap between the first boss portion 60 and the second shaft portion 22b is sealed by oil seals 65, 66.

[0039] 5, a lubricant reservoir 61 filled with a lubricant is provided within the first boss hole 60a. The lubricant reservoir 61 is disposed between a pair of bushings 63, 64. The lubricant reservoir 61 includes a first reservoir portion 61a, a second reservoir portion 61b, and a plurality of connection holes 61c.

[0040] The first reservoir 61a is disposed between the outer peripheral surface of the first shaft portion 22a and the inner peripheral surface of the second shaft portion 22b. The first reservoir 61a extends in the axial direction. As shown in FIGS. 3 to 5, the first reservoir 61a overlaps with the pair of bushings 63, 64 when viewed in the radial direction of the crankshaft 22. Specifically, the first reservoir 61a overlaps with the area of ​​the second shaft portion 22b in which the pair of bushings 63, 64 slide in the radial direction of the crankshaft 22.

[0041] The second reservoir 61b is disposed between the outer peripheral surface of the second shaft portion 22b and the inner peripheral surface of the first boss portion 60. The second reservoir 61b extends in the axial direction. The axial dimension of the second reservoir 61b is greater than the axial dimension of the spline teeth 22c. The second reservoir 61b overlaps with the first reservoir 61a when viewed in the radial direction of the crankshaft 22. The second reservoir 61b communicates with the first reservoir 61a via a plurality of connecting holes 61c.

[0042] As shown in Fig. 6, the multiple connection holes 61c extend in the radial direction of the crankshaft 22 and connect the first reservoir portion 61a and the second reservoir portion 61b. The multiple connection holes 61c are arranged between the pair of bushings 63, 64. The multiple connection holes 61c are arranged at intervals from one another in the circumferential direction of the crankshaft 22. The multiple connection holes 61c are arranged side by side with the spline teeth 22c in the circumferential direction of the crankshaft 22. The multiple connection holes 61c are arranged adjacent to the spline teeth 22c in the circumferential direction of the crankshaft 22.

[0043] The sheave drive mechanism 44 axially moves the first movable sheave 57. As shown in FIG.

[0044] 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.

[0045] 3 and 4, the first drive member 68 includes a first bore 72. The first bore 72 extends axially through the first drive member 68. The crankshaft 22 passes through the first bore 72. The first drive member 68 is supported on the crankshaft 22 via a bearing 50. The first drive member 68 is supported rotatably relative to the crankshaft 22. The first drive member 68 is supported so as to be immovable in the axial direction relative to the crankshaft 22.

[0046] 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 a gear 71. The rotation of the rotary 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 in the axial direction from the gear portion 73. A first screw 75 is provided on the outer circumferential surface of the feed screw portion 74.

[0047] A crankcase cover 76 is attached to the crankcase 21. The crankcase cover 76 includes an opening 76A. The opening 76A is disposed facing the primary pulley 41. The second driving member 69 extends 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.

[0048] The second drive member 69 includes a second bore 78. The second bore 78 extends axially through the second drive member 69. The crankshaft 22 and the first boss portion 60 extend through the second bore 78.

[0049] The second drive member 69 is supported by the first boss portion 60 via a bearing 79. 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 so as to be immovable in the axial direction. The second drive member 69 moves axially together with the first movable sheave 57. An oil seal 80 seals the gap between the second drive member 69 and the first boss portion 60. A second screw 81 is provided on the inner peripheral surface of the second drive member 69. The second screw 81 meshes with the first screw 75. When the first drive member 68 rotates, the second drive member 69 moves axially as shown in FIG. 4. This causes the first movable sheave 57 to move axially.

[0050] 7 and 8 are enlarged views showing the secondary pulley 42 and the centrifugal clutch 45. 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.

[0051] The second fixed sheave 82 includes a second sheave portion 84 and a second boss portion 85. The second sheave portion 84 is disposed opposite the second movable sheave 83. A second groove 42A is provided between the second sheave portion 84 and the second movable sheave 83. The second boss portion 85 extends in the axial direction from the second sheave portion 84. The second boss portion 85 includes a second boss hole 86. The second boss hole 86 extends in the axial direction through the second boss portion 85.

[0052] The output shaft 46 is rotatably supported by the transmission case 48 via a bearing 95. The output shaft 46 extends through the second boss hole 86. 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 inner peripheral surface of the second boss hole 86 and the outer peripheral surface of the output shaft 46.

[0053] The second boss portion 85 is rotatably supported on the output shaft 46 by a bushing 91 and a bearing 92. A lubricant such as grease is filled inside the second boss hole 86. An oil seal 93 seals the gap between the second boss portion 85 and the output shaft 46.

[0054] The second movable sheave 83 is disposed axially outward (to the right in FIG. 5) relative to the second fixed sheave 82. The second movable sheave 83 is supported non-rotatably relative to the second boss portion 85. The second movable sheave 83 rotates integrally with the second fixed sheave 82. The second movable sheave 83 is supported axially movably relative to the second boss portion 85. For example, the second movable sheave 83 is fixed to the second boss portion 85 by a spline. 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.

[0055] As shown in Fig. 7, 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. 8, 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.

[0056] 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.

[0057] 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).

[0058] The clutch outer 90 is fixed to the output shaft 46 by a nut 94. The clutch outer 90 rotates integrally with the output shaft 46. The clutch outer 90 covers the clutch shoes 89 in the radial direction.

[0059] When the vehicle speed is slower than a predetermined engagement speed, the clutch shoe 89 is separated from the clutch outer 90 by the biasing force of the clutch spring. Therefore, 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. When the vehicle speed is equal to or higher than the engagement speed, the clutch shoe 89 moves radially outward due to centrifugal force against the biasing force of the clutch spring. As a result, the clutch shoe 89 comes into contact with the clutch outer 90, and the centrifugal clutch 45 enters an engaged state. When the centrifugal clutch 45 is in an engaged state, the rotation of the secondary pulley 42 is transmitted to the output shaft 46 via the drive plate 88, the clutch shoe 89, and the clutch outer 90.

[0060] 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 engaged. 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. As a result, the saddle-type vehicle 1 travels.

[0061] 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.

[0062] Specifically, when the electric actuator 67 rotates the first driving member 68 in a certain direction, the second driving member 69 moves axially outward, as shown in FIG. 4. This causes the first movable sheave 57 to move axially outward together with the second driving member 69. When the first movable sheave 57 moves axially outward, the width of the first groove 41A between the first movable sheave 57 and the first fixed sheave 58 decreases. This increases the diameter of the portion of the belt 43 wound around the primary pulley 41 (hereinafter referred to as the "first winding diameter"). 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"). This decreases the gear ratio. In this case, as shown in FIG. 8, 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.

[0063] When the electric actuator 67 rotates the first driving member 68 in the reverse direction, the second driving member 69 moves axially inward, as shown in FIG. 4. As a result, the first moving sheave 57 moves axially inward together with the second driving member 69. When the first moving sheave 57 moves axially inward, the width of the first groove 41A between the first moving 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. 7, the second moving sheave 83 moves axially inward due to the biasing force of the spring 87, and the width of the second groove 42A decreases.

[0064] In the saddle-type vehicle 1 having the above-described configuration, in the continuously variable transmission 15, The pair of bushings 63, 64 disposed on both ends of the inner circumferential surface of the first boss portion 60 of the first movable sheave 57 can support the unbalanced load from the belt 43 of the continuously variable transmission 15, thereby improving the load-bearing capacity of the first movable sheave 57. Furthermore, a spline groove 60b is provided on the inner circumferential surface of the first boss portion 60, and spline teeth 22c are provided on the outer circumferential surface of the second shaft portion 22b, with the spline groove 60b having an axial dimension greater than the axial dimension of the spline teeth 22c. Therefore, the spline groove 60b can be wrapped around the crankshaft 22 in the radial direction within the range in which the pair of bushings 63, 64 slide on the second shaft portion 22b. This prevents the axial dimension of the crankshaft 22 from increasing.

[0065] 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.

[0066] 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. [Explanation of symbols]

[0067] 1: saddle-ride type vehicle, 15: continuously variable transmission, 22: crankshaft, 22c: spline teeth, 63, 64: pair of bushings, 57: first movable sheave, 60: first boss portion, 60b: spline groove, 61: lubricant reservoir, 61a: first reservoir portion, 61b: second reservoir portion, 61c: connection hole

Claims

1. An electronically controlled continuously variable transmission, A rotation axis; a pair of bushings arranged slidably in the axial direction of the rotary shaft relative to the rotary shaft; a movable sheave including boss portions disposed on outer peripheral surfaces of the pair of bushings, the movable sheave moving in the axial direction in response to sliding of the pair of bushings in the axial direction; Equipped with The pair of bushes are arranged on both ends of the inner circumferential surface of the boss portion. Continuously variable transmission.

2. the movable sheave includes a spline groove disposed on an inner peripheral surface of the boss portion, the rotating shaft includes spline teeth that are spline-fitted into the spline grooves, the spline grooves have an axial dimension greater than an axial dimension of the spline teeth; 2. The continuously variable transmission according to claim 1.

3. The spline teeth of the rotary shaft are formed integrally with the rotary shaft.

3. The continuously variable transmission according to claim 2.

4. A lubricant is sealed between the pair of bushes.

2. The continuously variable transmission according to claim 1.

5. Further provided is a lubricant reservoir in which the lubricant is sealed, the rotating shaft includes a first shaft portion and a second shaft portion disposed on an outer circumferential surface of the first shaft portion, The lubricant reservoir comprises: a first reservoir portion disposed between an outer peripheral surface of the first shaft portion and an inner peripheral surface of the second shaft portion; a second reservoir portion disposed between an outer peripheral surface of the second shaft portion and an inner peripheral surface of the boss portion; a connection hole extending in a radial direction of the rotary shaft and connecting the first reservoir portion and the second reservoir portion; Including, 5. The continuously variable transmission according to claim 4.

6. the second shaft portion includes spline teeth that are spline-fitted to an inner circumferential surface of the boss portion, the connecting hole of the lubricant reservoir is arranged side by side with the spline teeth in the circumferential direction of the rotary shaft, 6. The continuously variable transmission according to claim 5.

7. the boss portion of the movable sheave includes a spline groove that fits onto the spline teeth, the spline grooves have an axial dimension greater than an axial dimension of the spline teeth; 7. The continuously variable transmission according to claim 6.

8. A straddle-type vehicle comprising the continuously variable transmission according to any one of claims 1 to 6.

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