TWI687608B - CVT and bicycle - Google Patents

Abstract

The continuously variable transmission has a plurality of planetary rollers arranged around the main shaft. Both ends of the rotation shaft of the planetary roller are maintained to be displaceable in the radial direction relative to the main shaft. Each planetary roller has a first inclined surface in contact with the input rotating body and a second inclined surface in contact with the output rotating body. The inclination angle of the planetary roller will change according to the position of the movable ring in the axial direction. As a result, the contact position of the first inclined face to the input rotating body and the contact position of the second inclined face to the output rotating body are changed respectively. With this, the speed ratio between the input rotating body and the output rotating body can be switched. In addition, the first inclined surface of the planetary roller is spherical. Therefore, regardless of the inclination angle of the planetary roller, the direction and magnitude of the pressure generated by the contact point between the first inclined surface and the input rotating body are difficult to change.

Description

CVT and bicycle

Field of invention The invention relates to a continuously variable transmission and a bicycle.

Background of the invention In the past, bicycles with shifting mechanisms have been known. A general speed change mechanism of a bicycle is configured to convert a roller chain between a plurality of sprockets with different diameters. When the user of the bicycle operates the shift lever of the handle portion, the roller chain changes to the sprocket designated by the shift lever. As a result, the rear wheels rotate at a gear ratio that corresponds to the diameter of the sprocket. However, in such a general transmission mechanism, the transmission ratio can only be switched by the number of stages corresponding to the number of sprockets.

In this regard, Japanese Patent Laid-Open No. 2016-70393 describes a bicycle transmission that can continuously change the transmission ratio. The transmission of this publication changes the ratio of the rotation speed of the first rotating body and the second rotating body by tilting the support pins of the planetary rollers arranged around the main shaft.

However, in the transmission of Japanese Patent Laid-Open No. 2016-70393, the rotation surface of the input side of the planetary roller becomes a conical surface. Therefore, the angle of the rotating surface on the input side also changes according to the tilt angle of the planetary roller. As a result, the direction and magnitude of the pressure applied to the rotating surface on the input side will greatly change. If the pressure applied to the rotating surface on the input side is too large, the resistance will increase and the efficiency of power transmission will be easily reduced. In addition, if the pressure applied to the rotating surface on the input side is too small, it is easy to cause the planetary roller to slip.

Summary of the invention An object of the present invention is to provide a continuously variable transmission in which a gear ratio is switched by changing the inclination angle of a planetary roller, so that the direction and magnitude of the pressure generated by the contact point between the planetary roller and the input rotating body are not easy Changed structure.

The exemplary first invention of the present case is a continuously variable transmission including: an input rotating body centered on a main shaft and rotating at a rotation speed before shifting; an output rotating body centering on the aforementioned main shaft and rotating at a rotation speed after shifting A plurality of planetary rollers, which are arranged around the main shaft and can rotate around the rotation shaft; guide members limit the positions of the two ends of the rotation shaft; and an annular movable ring can use the main shaft The center roller rotates and is movable in the axial direction. The planetary roller has a spherical first inclined surface in contact with the input rotating body; a conical second inclined surface in contact with the output rotating body; and a ring shape The concave portion or the ring-shaped convex portion is engaged with the movable ring, the guide member holds both ends of the rotation shaft at different positions in the circumferential direction, and both ends of the rotation shaft are held by the guide Component, and can be displaced in the radial direction with respect to the aforementioned main shaft.

According to the exemplified first invention of the present case, the inclination angle of the rotation axis of the planetary roller in the cross section including the main shaft changes according to the position of the movable ring in the axial direction. As a result, the contact position of the first inclined face to the input rotating body and the contact position of the second inclined face to the output rotating body are changed respectively. With this, the speed ratio between the input rotating body and the output rotating body can be switched.

Furthermore, according to the exemplary first invention of the present case, the first inclined surface of the planetary roller is spherical. Therefore, regardless of the inclination angle of the planetary roller, the direction and magnitude of the pressure generated by the contact point between the first inclined surface and the input rotating body are difficult to change.

Forms for carrying out the invention Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. Furthermore, in this case, the direction parallel to the main shaft of the continuously variable transmission is called "axial direction", and the direction orthogonal to the main shaft is called "radial direction". The direction is called "circumferential direction". However, the above “parallel direction” also includes a substantially parallel direction. In addition, the above-mentioned "orthogonal direction" also includes a substantially orthogonal direction. In this case, the end of the member near the sprocket is called "one end", and the end away from the sprocket is called "the other end".

＜1. About bicycle＞ FIG. 1 is a schematic diagram of a bicycle 100 using a continuously variable transmission 1 according to an embodiment of the present invention. As shown in FIG. 1, the bicycle 100 includes a front wheel 110, a rear wheel 120, a foot pedal 130, a roller chain 140, and a continuously variable transmission 1. The continuously variable transmission 1 is a hub built in the center of the wheel 121 provided on the rear wheel 120. When the user pedals the foot pedal 130 in the forward direction, the rotation motion of the foot pedal 130 is transmitted to the continuously variable transmission 1 through the roller chain 140. In addition, the continuously variable transmission 1 shifts the rotational motion received from the roller chain 140 and then transmits it to the rear wheel 120. The rear wheel 120 rotates at the rotation speed shifted by the continuously variable transmission 1. Furthermore, the bicycle 100 may also have a motor for assisting the rotational movement of the foot pedal 130.

＜2. Composition of continuously variable transmission＞ 2 to 4 are longitudinal cross-sectional views of the continuously variable transmission 1. The continuously variable transmission 1 is a mechanism that outputs the rotational motion obtained from the roller chain 140 to the rear wheels 120 at a constant speed, or decelerates or accelerates. FIG. 2 is a cross section showing the continuously variable transmission 1 at constant speed. FIG. 3 is a cross section showing the continuously variable transmission 1 during deceleration. FIG. 4 is a cross section showing the continuously variable transmission 1 during acceleration. As shown in FIGS. 2 to 4, the continuously variable transmission 1 of the present embodiment includes a hollow shaft 10, an input rotating body 20, a plurality of planetary rollers 30, a guide member 40, a movable ring 50, an operation unit 60, and Output rotating body 70.

The hollow shaft 10 is a cylindrical member extending along the main shaft 9. The material of the hollow shaft 10 is metal such as stainless steel. The input rotating body 20, the movable ring 50, and the output rotating body 70 described below are supported by the hollow shaft 10 via bearings. When the continuously variable transmission 1 is mounted on the bicycle 100, the continuously variable transmission 1 is arranged so that the central axis of the hollow shaft 10, that is, the main shaft 9 and the central axis of the rear wheel 120 coincide.

The input rotor 20 rotates around the main shaft 9 as the roller chain 140 rotates. As shown in FIGS. 2 to 4, the input rotating body 20 of this embodiment includes a sprocket 21, a relay member 22, and a pressure regulating cam 23.

The relay member 22 has a cylindrical portion 221 and a flange portion 222. The cylindrical portion 221 extends around the hollow shaft 10 in a cylindrical shape in the axial direction. The flange portion 222 extends from the end of the cylindrical portion 221 in the axial direction toward the outside in the radial direction. The flange portion 222 is located inside the housing 72 described later. Between the relay member 22 and the hollow shaft 10, a pair of first bearings 24 are provided. For the first bearing 24, for example, a ball bearing is used. The relay member 22 is supported rotatably with respect to the hollow shaft 10 via the first bearing 24.

The sprocket 21 is fixed to the outer peripheral surface of the cylindrical portion 221. The roller chain 140 of the bicycle 100 is engaged with a plurality of gear teeth provided on the outer peripheral surface of the sprocket 21. When the bicycle 100 travels, as the roller chain 140 rotates, the sprocket 21 and the relay member 22 rotate around the main shaft 9 and rotate at the rotation speed before shifting. Hereinafter, the rotation speeds of the sprocket 21 and the relay member 22 are referred to as "first rotation speed".

The pressure-regulating cam 23 is a mechanism that generates a thrust in the axial direction on the planetary roller 30 in response to the load in the rotation direction. The pressure regulating cam 23 has a first cam member 231 and a second cam member 232 arranged in the axial direction, and a plurality of rotating bodies 233. The first cam member 231 and the second cam member 232 are annular members centered on the main shaft 9. The first cam member 231 and the flange portion 222 of the relay member 22 are fixed to each other by screwing, for example. The plural rotating bodies 233 are spherical members interposed between the first cam member 231 and the second cam member 232.

5 and 6 are side views of the pressure regulating cam 23. As shown in FIGS. 5 and 6, the first cam member 231 and the second cam member 232 each have a plurality of first cam surfaces 23 a and a plurality of second cam surfaces 23 b. The rotating body 233 is a space accommodated between the first cam surface 23a and the second cam surface 23b of the first cam member 231 and the first cam surface 23a and the second cam surface 23b of the second cam member 232.

The angle of the first cam surface 23a with respect to the circumferential direction is smaller than the angle of the second cam surface 23b with respect to the circumferential direction. The angle of the first cam surface 23a with respect to the circumferential direction may be, for example, 3° or more and 35° or less. The angle of the second cam surface 23b with respect to the circumferential direction may be, for example, 70° or more and less than 90°.

When the user of the bicycle 100 pedals on the foot pedal 130, the input rotor 20 rotates in the forward direction. At this time, as shown in FIG. 5, each rotating body 233 moves along the first cam surface 23 a while contacting the first cam surface 23 a of the first cam member 231 and the first cam surface 23 a of the second cam member 232. Displacement in ascending direction. In this way, the rotating body 233 moves the second cam member 232 in the separation direction based on the first cam member 231 as a reference. Therefore, the contact pressure between the second cam member 232 and the planetary roller 30, which will be described later, increases.

On the other hand, if the user of the bicycle 100 rotates the foot pedal 130 in the reverse direction, or rotates at a speed lower than that of the rear wheel 120, the input rotor 20 will also rotate in the reverse direction. At this time, as shown in FIG. 6, each rotating body 233 is in contact with the second cam surface 23 b of the first cam member 231 and the second cam surface 23 b of the second cam member 232. As a result, the rotating body 233 does not change the positional relationship between the second cam surface 23b of the first cam member 231 and the second cam surface 23b of the second cam member 232 in the circumferential direction and the axial direction without changing the positional relationship The first cam member 231 and the second cam member 232 rotate integrally. Therefore, the contact pressure between the second cam member 232 and the planetary roller 30 described later will be weakened. Thereby, the input rotating body 20 and the output rotating body 70 are idling. In other words, the pressure regulating cam 23 allows the continuously variable transmission 1 to function as a one-way clutch.

In addition, a thrust bearing 25 is provided between the first cam member 231 of the pressure regulating cam 23 and the housing 72 described later. For the thrust bearing 25, for example, a needle bearing is used. The first cam member 231 and the housing 72 can rotate relative to each other via the thrust bearing 25. Thereby, the input rotating body 20 and the output rotating body 70 can be rotated at different rotation speeds.

Plural planet rollers 30 are arranged around the main shaft 9. The planetary rollers 30 are supported so as to be rotatable about a swingable rotation axis 300. As shown in FIGS. 2 to 4, the surface of each planetary roller 30 has a first inclined surface 301, a second inclined surface 302, and an annular concave portion 303. The first inclined surface 301 is a hemispherical (spherical) surface and gradually expands in diameter as it moves away from one end of the rotation shaft 300, and is centered around the center of the rotation shaft 300. The first inclined surface 301 is in contact with the second cam member 232. The second inclined surface 302 is a conical surface, and gradually expands in diameter as it moves away from the other end of the rotation shaft 300. The second inclined surface 302 is in contact with the contact member 71 of the output rotor 70 described later.

The annular concave portion 303 is an annular groove with the rotation axis 300 as the center. The annular concave portion 303 is located between the first inclined surface 301 and the second inclined surface 302. As shown in FIGS. 2 to 4, the shape of the annular concave portion 303 is substantially arc-shaped in a cross section including the main shaft 9. The annular concave portion 303 is in contact with the annular convex portion 51 of the movable ring 50 described later.

In this way, the planetary roller 30 contacts the input rotor 20, the output rotor 70, and the movable ring 50, and is supported by the three contact points.

FIG. 7 is an exploded cross-sectional view of the planetary roller 30. As shown in FIG. 7, the planetary roller 30 of the present embodiment is formed by combining the first planetary member 31 and the second planetary member 32 in the axial direction. The first planetary member 31 is a hemispherical member having a first inclined surface 301. The second planetary member 32 is a conical member having a second inclined surface 302 and an annular recess 303. When the first planetary member 31 and the second planetary member 32 are combined, for example, the cylindrical protrusion 304 provided in the second planetary member 32 is pressed into the first planetary member 31. However, the method of fixing the first planetary member 31 and the second planetary member 32 may be other methods such as welding.

In order to reduce the weight of the planetary roller 30, it is preferable to have a cavity 33 inside. As in the present embodiment, as long as the first planetary member 31 and the second planetary member 32 are combined, it is possible to easily form the planetary roller 30 having the cavity 33 therein.

In this embodiment, the entire annular recess 303 belongs to the second planetary member 32. That is, the annular concave portion 303 is not divided into two members. In this way, it is possible to suppress the generation of minute steps on the surface of the annular recess 303. That is, the dimensional accuracy of the annular recess 303 can be improved. In addition, the rigidity of the annular recess 303 can also be increased. Therefore, the annular convex portion 51 of the movable ring 50 described later can be accurately contacted with the annular concave portion 303. In addition, the annular recess 303 may also belong to the first planetary member 31.

The guide member 40 includes a first guide plate 41 and a second guide plate 42. The first guide plate 41 and the second guide plate 42 are disk-shaped members fixed to the hollow shaft 10. The first guide plate 41 and the second guide plate 42 cannot rotate relative to the hollow shaft 10. As shown in FIGS. 2 to 4, the first guide plate 41 and the second guide plate 42 are located on both sides of the planetary roller 30 in the axial direction. In addition, the first guide plate 41 and the second guide plate 42 each extend radially outward with respect to the main shaft 9.

The first guide plate 41 is provided with a plurality of first notches 410 at equal intervals in the circumferential direction. Each first notch 410 is recessed radially inward from the outer peripheral portion of the first guide plate 41. The second guide plate 42 is provided with a plurality of second notches 420 at equal intervals in the circumferential direction. Each second notch 420 is recessed radially inward from the outer peripheral portion of the second guide plate 42. One end of the rotation axis 300 of the planetary roller 30 is fitted into the first notch 410. The other end of the rotation axis 300 of the planetary roller 30 is fitted into the second notch 420. With this, the positions of both ends of the rotation shaft 300 of the planetary roller 30 in the circumferential direction are restricted.

One end of the rotation shaft 300 can be displaced in the radial direction along the first notch 410. In addition, the other end of the rotation shaft 300 can be displaced in the radial direction along the second notch 420. As will be described later, both ends of the rotation shaft 300 are displaced in the radial direction according to the position of the movable ring 50 in the axial direction. Thereby, the inclination angle of the rotation shaft 300 in the section including the main shaft 9 is changed. In this way, the position at which the both ends of the rotation shaft 300 are displaced in the radial direction to tilt the rotation shaft 300 of the planetary roller 30 relative to the main shaft 9 is hereinafter referred to as "tilt in the radial direction".

The movable ring 50 is an annular member located radially outside of the hollow shaft 10 and radially inside of the planetary roller 30. The movable ring 50 has an annular convex portion 51 protruding outward in the radial direction. As shown in FIGS. 2 to 4, the shape of the annular convex portion 51 is substantially arc-shaped in a cross section including the main shaft 9. The annular convex portion 51 is an annular concave portion 303 fitted into the planetary roller 30. Thereby, the movable ring 50 and the planetary roller 30 will be engaged.

The movable ring 50 is supported by the hollow shaft 10 via the engagement member 81 and the second bearing 82. The second bearing 82 is, for example, a ball bearing. The movable ring 50 is an outer ring fixed to the second bearing 82. Therefore, the movable ring 50 can rotate relatively with respect to the hollow shaft 10 and the engaging member 81 with the main shaft 9 as the center.

In addition, as shown in FIGS. 2 to 4, the hollow shaft 10 has a slit 11 extending in the axial direction. The engaging member 81 is an inner wheel fixed to the second bearing 82, and is engaged with the slit 11 so as to be slidable in the axial direction. Therefore, the engaging member 81, the second bearing 82, and the movable ring 50 as a whole are movable along the slit 11 in the axial direction.

The operation portion 60 is a mechanism for switching the position of the movable ring 50 in the axial direction. As shown in FIGS. 2 to 4, the operation unit 60 has a lever 61 and a thread mechanism 62. The rod 61 is a cylindrical member inserted inside the hollow shaft 10. The rod 61 extends in the axial direction along the main shaft 9. The thread mechanism 62 is connected to one end of the rod 61. The engaging member 81 is fixed to the other end of the rod 61. The user of the bicycle 100 can change the position of the lever 61 in the axial direction by operating the wire mechanism 62. When the rod 61 moves in the axial direction, the engaging member 81, the second bearing 82, and the movable ring 50 also move in the axial direction along the slit 11. In addition, as the movable ring 50 moves in the axial direction, the engagement position of the annular convex portion 51 and the annular concave portion 303 also changes in the axial direction. As a result, the inclination angle of the planetary roller 30 in the radial direction is changed.

However, the operation portion 60 can also be realized by other mechanisms such as screws that can be positioned in the axial direction.

The output rotating body 70 is centered on the main shaft 9 and rotates at a rotation speed after shifting. Hereinafter, the rotation speed after shifting is referred to as "second rotation speed". As shown in FIGS. 2 to 4, the output rotating body 70 of this embodiment includes a contact member 71 and a housing 72. The contact member 71 is an annular member centered on the main shaft 9. The contact member 71 is in contact with the second inclined surface 302 of the planetary roller 30. The housing 72 is an annular frame that houses the pressure regulating cam 23, the plurality of planetary rollers 30, the guide member 40, and the movable ring 50 inside. The housing 72 is supported by the hollow shaft 10 via the third bearing 73. In addition, the housing 72 is supported by the relay member 22 via the fourth bearing 74.

The contact member 71 and the housing 72 are fixed so as not to rotate relative to each other. Therefore, when the contact member 71 rotates with the rotation of the planetary roller 30, the housing 72 also rotates at the second rotation speed with the contact member 71 centering on the main shaft 9 as the center. In addition, the housing 72 is a hub fixed to the center of the wheel 121 of the rear wheel 120 of the bicycle 100. Therefore, as the housing 72 rotates, the rear wheel 120 of the bicycle 100 also rotates at the second rotation speed.

＜3. About shifting motion＞ Next, the shifting operation of the continuously variable transmission 1 described above will be described.

If the input rotor 20 rotates at the first rotation speed by the power obtained from the roller chain 140, the second cam member 232 of the pressure regulating cam 23 also contacts the first inclined surface 301 of the planetary roller 30 while Rotate at 1st speed. As a result, the planetary roller 30 rotates about the rotation axis 300 by the frictional force between the second cam member 232 and the first inclined surface 301. In addition, the output rotating body 70 rotates at the second rotation speed due to the friction between the second inclined surface 302 and the contact member 71.

Here, as described above, in this embodiment, the tilting angle of the planetary roller 30 in the radial direction can be changed by the user of the bicycle 100 operating the operation portion 60.

For example, as shown in FIG. 3, when the planetary roller 30 is inclined in the radial direction and one end of the rotation shaft 300 is close to the main shaft 9, the point where the first inclined surface 301 contacts the input rotor 20 is away from the rotation shaft 300 The distance will become larger. In addition, the distance from the rotation axis 300 where the second inclined surface 302 contacts the output rotating body 70 becomes smaller. Therefore, the second rotation speed of the rotation speed of the output rotating body 70 becomes smaller than the first rotation speed of the input rotation body 20. That is, the rotational motion of the input rotating body 20 is decelerated and output from the output rotating body 70 toward the rear wheel 120.

On the other hand, as shown in FIG. 4, when the planetary roller 30 is inclined in the radial direction and one end of the rotation shaft 300 is away from the main shaft 9, the point where the first inclined surface 301 contacts the input rotor 20 is away from rotation The distance of the axis 300 will become smaller. In addition, the distance from the rotation axis 300 where the second inclined surface 302 contacts the output rotating body 70 becomes larger. Therefore, the second rotation speed, which is the rotation speed of the output rotating body 70, becomes larger than the first rotation speed, which is the rotation speed of the input rotating body 20. That is, the rotational motion of the input rotating body 20 is accelerated and output from the output rotating body 70 toward the rear wheel 120.

In this way, in the continuously variable transmission 1 of the present embodiment, the inclination angle of the rotation shaft 300 of the planetary roller 30 in the cross section including the main shaft 9 changes depending on the position of the movable ring 50 in the axial direction. In this way, the contact position of the first inclined surface 301 to the input rotating body 20 and the contact position of the second inclined surface 302 to the output rotating body 70 are changed respectively. With this, the speed ratio between the input rotating body 20 and the output rotating body 70 can be switched.

8 to 10 are diagrams showing the pressure F1 generated by the contact point between the second cam member 232 and the first inclined surface 301 and the pressure F2 generated by the contact point between the contact member 71 and the second inclined surface 302. FIG. 8 shows the state at constant speed, FIG. 9 shows the state at deceleration, and FIG. 10 shows the state at acceleration.

The first inclined surface 301 is spherical. Therefore, regardless of the inclination angle of the planetary roller 30 in the radial direction, the inclination angle of the first inclined surface 301 at the contact point between the second cam member 232 and the first inclined surface 301 is fixed. Therefore, regardless of the tilt angle of the planetary roller 30 in the radial direction, the direction of the pressure F1 generated by the contact point is also fixed. Therefore, if the torque input to the input rotating body 20 is fixed, as shown in FIGS. 8 to 10, the pressure F1 generated at the contact point under any of the conditions of constant speed, deceleration, and acceleration The size will not change.

If the pressure F1 is too small, slippage between the second cam member 232 and the first inclined surface 301 is likely to occur. Moreover, if the pressure F1 is too large, rolling resistance more than necessary is generated between the second cam member 232 and the first inclined surface 301, and it becomes easy to reduce the power transmission efficiency. In addition, if the pressure F1 is too large, damage to the second cam member 232 or the first inclined surface 301 may easily occur. As described in this embodiment, regardless of the angle of inclination of the planetary roller 30 in the radial direction, as long as the pressure F1 is fixed, these problems can be solved.

Furthermore, the shape of the first inclined surface 301 may not be strictly along the shape of a sphere. That is, the "spherical shape" in the present invention also includes a substantially spherical shape. In addition, the direction and magnitude of the pressure F1 generated at the contact point between the second cam member 232 and the first inclined surface 301 may not be completely fixed. As long as the first inclined surface 301 is "spherical", it is sufficient to suppress the change in the direction and magnitude of the pressure F1 generated at the contact point.

On the other hand, the second inclined surface 302 is conical. Therefore, as shown in FIGS. 8 to 10, the inclination angle of the second inclined surface 302 at the contact point between the contact member 71 and the second inclined surface 302 changes according to the inclination angle of the planetary roller 30 in the radial direction. Therefore, the direction of the pressure F2 generated by the contact point also changes according to the tilt angle of the planetary roller 30 in the radial direction. Therefore, as shown in FIG. 9, the pressure F2 during deceleration becomes larger than the pressure F2 during constant speed. Also, as shown in FIG. 10, the pressure F2 during acceleration becomes smaller than the pressure F2 at constant speed.

In this way, the pressure F2 according to the gear ratio can be generated at the contact point between the contact member 71 and the second inclined surface 302.

As shown in FIGS. 8 to 10, the closer the conical second inclined surface 302 is to the position of its vertex, the greater the pressure will be. Therefore, in this embodiment, as shown in FIG. 7, the conical second planetary member 32 is thickened toward the apex. That is, the thickness of the second planetary member 32 in the axial direction or the radial direction increases toward the apex. In this way, the deformation of the second planet member 32 due to the load during use can be suppressed. On the other hand, the spherical first inclined surface 301 receives a fixed pressure regardless of its contact position. Therefore, in the present embodiment, as shown in FIG. 7, the thickness of the hemispherical first planetary member 31 in the axial direction or the radial direction is set to a fixed thinness.

<4. Modifications>

Although the exemplary embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments.

<4-1. First modification>

FIG. 11 is a diagram showing the planetary roller 30A and the movable ring 50A of the first modification. In the example of FIG. 11, the axial width d1 of the annular concave portion 303A of the planetary roller 30A is greater than the axial width d2 of the annular convex portion 51A provided on the outer peripheral portion of the movable ring 50A. Further, in a cross section including the main axis, the radius of curvature of the annular concave portion 303A is larger than the radius of curvature of the annular convex portion 51A. As a result, the contact between the planetary roller 30A and the movable ring 50A becomes a single-point contact, which reduces the rolling resistance. In addition, the corners at both ends of the annular recess 303A in the axial direction do not come into contact with the movable ring 50A. Therefore, the contact resistance between the planetary roller 30A and the movable ring 50A can be reduced.

<4-2. Second modification> 12 is a longitudinal cross-sectional view of a continuously variable transmission 1B according to a second modification. In the example of FIG. 12, the coil spring 90B is provided inside the hollow shaft 10B. The coil spring 90B is an elastic member that can expand and contract in the axial direction. One end of the coil spring 90B in the axial direction, that is, the free end is in contact with the engaging member 81B. In addition, a positioning member 12B is arranged inside the hollow shaft 10B. The other end of the coil spring 90B in the axial direction, that is, the fixed end is in contact with the positioning member 12B. In this way, the coil spring 90B is arranged between the positioning member 12B and the engaging member 81B in a state where it is compressed compared to the natural length. Therefore, the coil spring 90B always presses the engaging member 81B, the second bearing 82B, and the movable ring 50B in a direction away from the positioning member 12B in the axial direction. That is, the coil spring 90B always applies a biasing force toward the one end side in the axial direction to the engaging member 81B, the second bearing 82B, and the movable ring 50B.

13 is a plan view of the first guide plate 41B and the second guide plate 42B of the second modification viewed from one side of the main shaft 9B. FIG. 14 is a view of the planetary roller 30B of the second modification from the outside in the radial direction. In this modification, the first guide plate 41B also has a plurality of first notches 410B. In addition, the second guide plate 42B also has a plurality of second notches 420B. However, as shown in FIGS. 13 and 14, in this modification, the position of the first notch 410B in the circumferential direction with respect to the main shaft 9B is slightly different from the position of the second notch 420B in the circumferential direction with respect to the main shaft 9B . Therefore, as shown in FIG. 14, both ends of the rotation shaft 300B are held at different positions in the circumferential direction by the first guide plate 41B and the second guide plate 42B. In this way, a state in which the positions of both ends of the rotation shaft 300B in the circumferential direction are different is hereinafter referred to as a “state inclined in the circumferential direction”. The planetary roller 30B is supported in a state of always being inclined in the circumferential direction.

If the input rotor 20B rotates at the first rotation speed by the power obtained from the roller chain, the second cam member 232B of the pressure regulating cam 23B also contacts the first inclined surface 301B of the planetary roller 30B while 1 rotation speed. As a result, the planetary roller 30B rotates about the rotation axis 300B due to the friction between the second cam member 232B and the first inclined surface 301B. In addition, the output rotating body 70B rotates at the second rotation speed due to the friction between the second inclined surface 302B and the contact member 71B. At this time, as indicated by the arrow in FIG. 14, the second inclined surface 302B of the planetary roller 30B applies a force Fo in the tangential direction proportional to the torque to the contact member 71B.

Here, as described above, the planetary roller 30B is supported in a state of being inclined in the circumferential direction. Therefore, due to the force Fo, a component force Fa in the circumferential direction centering on the rotation axis 300B and a component force Fb in the direction parallel to the rotation axis 300B are generated. If the inclination angle of the planetary roller 30B in the circumferential direction is θ, the relationship between the component force Fa and the component force Fb will satisfy Fb=Fa‧tan θ. When the component force Fb in the direction parallel to the rotation axis 300B is applied to the contact member 71B, the planetary roller 30B receives the reaction force Fc of the same magnitude as the component force Fb from the contact member 71B. This reaction force Fc becomes a force to tilt the rotation axis 300B in the radial direction, and causes the end of the rotation axis 300B (the end on the input rotor 20B side) of the planetary roller 30B to approach the main shaft 9B.

On the other hand, the coil spring 90B presses the engaging member 81B, the second bearing 82B, and the movable ring 50B in a direction away from the positioning member 12B in the axial direction. Therefore, as shown in FIG. 12, the planetary roller 30B receives the axial force Fd from the movable ring 50B. This force Fd becomes a force to tilt the rotation shaft 300B in the radial direction, and moves one end of the planetary roller 30B away from the main shaft 9B. In addition, as the end of the rotation axis 300B of the planetary roller 30B inclines closer to the main shaft 9B, the force Fd becomes larger as the coil spring 90B is compressed.

In this way, in a state where a load has been applied to the input rotating body 20B, two forces Fc and Fd that are to tilt the rotation shaft 300B in directions opposite to each other in the radial direction are applied to the planetary roller 30B. The rotation shaft 300B will be stationary at an inclination angle where these forces Fc and Fd are balanced. In addition, the planetary roller 30B rotates about the rotation axis 300B of its tilt angle.

For example, when the load is large (when the force Fo is strong), the component Fb of the force Fo also becomes large. Therefore, the reaction force Fc of the component force Fb also becomes larger. Therefore, the planetary roller 30B is inclined in the radial direction, and one end of the rotation shaft 300B approaches the main shaft 9B. In this case, the rotational motion of the input rotating body 20B is decelerated and output from the output rotating body 70B toward the rear wheel. On the other hand, when the load is small (when the force Fo is weak), the component Fb of the force Fo also becomes small. Therefore, the reaction force Fc of the component force Fb also becomes smaller. Therefore, the planetary roller 30B is inclined in the radial direction, and one end of the rotation shaft 300B is away from the main shaft 9B. In this case, the rotational motion of the input rotating body 20B is accelerated and output from the output rotating body 70B toward the rear wheel.

In this way, in the continuously variable transmission 1B of FIG. 12, the inclination angle of the rotation axis 300B of the planetary roller 30B in the radial direction changes according to the load applied to the planetary roller 30B. Therefore, the speed ratio between the input rotating body 20B and the output rotating body 70B can be automatically switched according to the load.

Furthermore, in the example of FIG. 12, the positioning member 12B is fixed to the other end of the rod 61B. Therefore, the user of the bicycle can adjust the positions of the lever 61B and the positioning member 12B in the axial direction by operating the operation portion 60B. When the position of the positioning member 12B in the axial direction changes, the position of the fixed end of the coil spring 90B also changes. In this way, the pressure applied from the coil spring 90B to the engaging member 81B, the second bearing 82B, and the movable ring 50B is changed. That is, the above Fd will be changed. Therefore, the relationship between the load and the gear ratio can be adjusted.

For example, if the position of the positioning member 12B in the axial direction is changed in a direction close to the input rotating body 20B, the above-mentioned force Fd becomes larger. Therefore, it becomes easy to accelerate the rotational motion of the input rotating body 20B. On the other hand, if the position of the positioning member 12B in the axial direction is changed away from the input rotor 20B, the force Fd becomes smaller. Therefore, it becomes easy to decelerate the rotational motion of the input rotating body 20B.

<4-3. Third modification>

15 is a longitudinal cross-sectional view of a continuously variable transmission 1C according to a third modification. The continuously variable transmission 1C of FIG. 15 has a solid input shaft 10C instead of the hollow shaft 10 in the above embodiment. In addition, the first cam member 231C of the pressure regulating cam 23C is fixed to the input shaft 10C without interposing the relay member. Further, the second cam member 232C of the pressure regulating cam 23C is radially inward of the rotation shaft 300C, and is in contact with the first inclined surface 301C of the planetary roller 30C.

In the example of FIG. 15, the output rotating body 70C has a contact member 71C and an output shaft 73C. The contact member 71C is more radially inward than the rotation axis 300C and is in contact with the second inclined surface 302C of the planetary roller 30C. The output shaft 73C extends along the main shaft 9C. The contact member 71C and the output shaft 73C are fixed so as not to rotate relative to each other.

In addition, in the example of FIG. 15, the movable ring 50C and the operating portion 60C are located radially outward of the planetary roller 30C. The movable ring 50C has an annular convex portion 51C protruding radially inward. The annular convex portion 51C is an annular concave portion 303C fitted into the planetary roller 30C. As a result, the movable ring 50C and the planetary roller 30C are engaged. In addition, the movable ring 50C is supported by the engaging member 81C so as to be slidable in the circumferential direction. In addition, the movable ring 50C and the engaging member 81C can move in the axial direction along the guide portion (not shown). The user can switch the position of the movable ring 50C in the axial direction by operating the operation portion 60C connected to the engaging member 81C.

<4-4. Other modifications> In the above-described embodiment, of the input rotating body and the output rotating body, only the input rotating body is provided with a pressure regulating cam. However, a pressure regulating cam may be provided in the output rotating body.

Furthermore, in the above embodiment, the planetary roller has an annular recess, and the movable ring has an annular convex portion that will fit into the annular recess. However, the planetary roller may have an annular convex portion, and the movable ring may have an annular concave portion. In addition, a configuration may be adopted in which the annular convex portion of the planetary roller is fitted into the annular concave portion of the movable ring. In this case, if the planetary roller is formed by two members, the entire annular convex portion preferably belongs to any one of the two members.

Furthermore, in the above-mentioned embodiment, the stepless transmission for bicycles has been described. However, a continuously variable transmission having an equivalent structure can also be used for applications other than bicycles. For example, a continuously variable transmission having the same structure may be mounted on a tricycle, wheelchair, trolley, unmanned transport vehicle, robot, or the like.

In addition, the detailed shape of the continuously variable transmission and the bicycle may be different from the shape shown in the drawings in this case. In addition, each element appearing in the above-mentioned embodiment or modification may be appropriately combined within a range where no shield is generated.

The present invention can be applied to, for example, a continuously variable transmission and a bicycle.

1. 1B, 1C ‧‧‧ Stepless speed changer 9, 9B, 9C‧‧‧spindle 10、10B‧‧‧Hollow shaft 10C‧‧‧ input shaft 11‧‧‧ slit 12B‧‧‧Positioning member 20, 20B‧‧‧ input rotating body 21‧‧‧Sprocket 22‧‧‧Relay components 23, 23B, 23C ‧‧‧ pressure regulating cam 23a‧‧‧The first cam surface 23b‧‧‧Second cam surface 24‧‧‧First bearing 25‧‧‧thrust bearing 30, 30A, 30B, 30C ‧‧‧ planetary roller 31‧‧‧The first planetary component 32‧‧‧The second planetary component 33‧‧‧Empty 40‧‧‧Guiding member 41、41B‧‧‧First guide plate 42、42B‧‧‧Second guide plate 50, 50A, 50B, 50C ‧‧‧ movable ring 51, 51A, 51C 60、60B、60C‧‧‧Operation Department 61, 61B‧‧‧ 62‧‧‧ Line organization 70, 70B, 70C‧‧‧ output rotating body 71, 71B, 71C 72‧‧‧Shell 73‧‧‧3rd bearing 73C‧‧‧ output shaft 74‧‧‧ 4th bearing 81, 81B, 81C 82, 82B ‧‧‧ 2nd bearing 90B‧‧‧coil spring 100‧‧‧Bike 110‧‧‧Front wheel 120‧‧‧rear wheel 121‧‧‧wheel 130‧‧‧ foot pedal 140‧‧‧Roller chain 221‧‧‧Cylinder 222‧‧‧Flange 231, 231C‧‧‧The first cam member 232, 232B, 232C ‧‧‧ second cam member 233‧‧‧Rotating body 300, 300B, 300C 301, 301B, 301C 302, 302B, 302C ‧‧‧ second inclined surface 303, 303A, 303C 304‧‧‧protrusion 410、410B‧‧‧The first gap 420、420B‧‧‧The second gap F1, F2‧‧‧ pressure Fa, Fb‧‧‧component Fc‧‧‧Reaction Fd, Fo‧‧‧force d1, d2‧‧‧Width θ‧‧‧Tilt angle

FIG. 1 is a schematic diagram of a bicycle. 2 is a longitudinal sectional view of a continuously variable transmission. 3 is a longitudinal sectional view of a continuously variable transmission. 4 is a longitudinal sectional view of a continuously variable transmission. Fig. 5 is a side view of the pressure regulating cam. Fig. 6 is a side view of the pressure regulating cam. 7 is an exploded cross-sectional view of a planetary roller. FIG. 8 is a diagram showing the pressure generated by the contact point between the second cam member and the first inclined surface and the contact point between the contact member and the second inclined surface. 9 is a diagram showing the pressure generated by the contact point between the second cam member and the first inclined surface and the contact point between the contact member and the second inclined surface. 10 is a diagram showing the pressure generated by the contact point between the second cam member and the first inclined surface and the contact point between the contact member and the second inclined surface. 11 is a diagram showing a planetary roller and a movable ring of a first modification. 12 is a longitudinal sectional view of a continuously variable transmission according to a second modification. 13 is a plan view of the first guide plate and the second guide plate of the second modification viewed from one side of the main shaft. FIG. 14 is a diagram of the planetary roller of the second modification viewed from the outside in the radial direction. 15 is a longitudinal sectional view of a continuously variable transmission according to a third modification.

1‧‧‧CVT

9‧‧‧spindle

10‧‧‧Hollow shaft

11‧‧‧ slit

20‧‧‧input rotating body

21‧‧‧Sprocket

22‧‧‧Relay components

23‧‧‧pressure regulating cam

24‧‧‧First bearing

25‧‧‧thrust bearing

30‧‧‧Planetary roller

40‧‧‧Guiding member

41‧‧‧First guide plate

42‧‧‧Second guide plate

50‧‧‧movable ring

51‧‧‧Annular convex part

60‧‧‧Operation Department

61‧‧‧

62‧‧‧ Line organization

70‧‧‧ output rotating body

71‧‧‧Contact member

72‧‧‧Shell

73‧‧‧3rd bearing

74‧‧‧ 4th bearing

81‧‧‧snap member

82‧‧‧2nd bearing

221‧‧‧Cylinder

222‧‧‧Flange

231‧‧‧The first cam member

232‧‧‧Second cam member

233‧‧‧Rotating body

300‧‧‧spindle

301‧‧‧1st inclined surface

302‧‧‧The second inclined surface

303‧‧‧Annular recess

410‧‧‧The first gap

420‧‧‧The second gap

Claims (19)

A continuously variable transmission with: Enter the rotating body, take the main shaft as the center, and rotate at the speed before the speed change; Output rotating body, centering on the aforementioned main shaft, and rotating at the speed after speed change; A plurality of planetary rollers are arranged around the aforementioned main shaft and can rotate around the rotation axis; A guide member to limit the positions of the two ends of the aforementioned rotation shaft; and The ring-shaped movable ring can rotate around the aforementioned main shaft and can move in the axial direction. The characteristics of the aforementioned continuously variable transmission are: The aforementioned planetary roller has: The spherical first inclined surface is in contact with the input rotating body; A conical second inclined surface in contact with the aforementioned output rotating body; and The ring-shaped concave portion or ring-shaped convex portion is engaged with the movable ring, Both ends of the rotation shaft are held by the guide member and can be displaced in the radial direction relative to the main shaft. If the continuously variable transmission of claim 1, it is further equipped with: The operation portion switches the position of the movable ring in the axial direction. If the continuously variable transmission of claim 1, it is further equipped with: The elastic member applies a force in the axial direction to the aforementioned movable ring, The guide member holds the two ends of the rotation shaft at different positions in the circumferential direction. The continuously variable transmission according to any one of claims 1 to 3, wherein the movable ring is located radially inward of the planetary roller. The continuously variable transmission according to any one of claims 1 to 3, wherein the movable ring is located radially outward of the planetary roller. If the continuously variable transmission according to any one of claims 1 to 3 is further provided with: The shaft body extends along the aforementioned main axis, The input rotating body, the output rotating body, and the movable ring are supported by the shaft body through bearings, respectively. The continuously variable transmission according to claim 6, wherein the aforementioned guide member has: The first guide plate is fixed to the shaft body and has a first gap into which one end of the rotation shaft of the planetary roller is fitted; and The second guide plate is fixed to the shaft body, and has a second notch into which the other end of the rotation shaft of the planetary roller is fitted. The continuously variable transmission according to any one of claims 1 to 3, wherein the annular concave portion or the annular convex portion is located between the first inclined surface and the second inclined surface. The continuously variable transmission according to any one of claims 1 to 3, wherein the planetary roller has the annular recess, and the outer peripheral portion of the movable ring is in contact with a surface of the planetary roller that constitutes the annular recess. The continuously variable transmission according to claim 9, wherein the radius of curvature of the annular recess is larger than the radius of curvature of the outer periphery of the movable ring in the section including the main shaft. The continuously variable transmission according to any one of claims 1 to 3, wherein the input rotating body includes a pressure-regulating cam that generates an axial pushing force on the planetary roller in response to a load in the direction of rotation. The continuously variable transmission according to claim 11, wherein the aforementioned pressure regulating cam has: A pair of circular cam members arranged in the axial direction; and The rotating body, between a pair of the aforementioned cam members, A pair of the aforementioned cam members each have: The first cam surface is in contact with the rotating body when the input rotating body rotates in one direction; and The second cam surface contacts the rotating body when the input rotating body rotates in the other direction, The angle of the first cam surface with respect to the circumferential direction is smaller than the angle of the second cam surface with respect to the circumferential direction. The continuously variable transmission according to claim 12, wherein the angle of the first cam surface relative to the circumferential direction is 3° or more and 35° or less, and the angle of the second cam surface relative to the circumferential direction is 70° or more and less than 90 °. The continuously variable transmission according to any one of claims 1 to 3, wherein the aforementioned planetary roller has a cavity inside. The continuously variable transmission according to claim 14, wherein the aforementioned planetary roller has: A first planet member having the aforementioned first inclined surface; and The second planetary member has the aforementioned second inclined surface. The continuously variable transmission according to claim 15, wherein the thickness of the first planetary member in the axial or radial direction is fixed, and the thickness of the second planetary member in the axial or radial direction will increase toward the second planetary The apex of the component is increased. The continuously variable transmission according to claim 15, wherein the annular concave portion or the entire annular convex portion belongs to any one of the first planetary member and the second planetary member. The continuously variable transmission according to any one of claims 1 to 3 is used for bicycles. A bicycle using a continuously variable transmission as in claim 18.

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