JP7207320B2 - continuously variable transmission and bicycle - Google Patents

Description

The present invention relates to continuously variable transmissions and bicycles.

Conventionally, a bicycle having a transmission mechanism is known. A general transmission mechanism for a bicycle has a structure in which a roller chain is exchanged between a plurality of sprockets with different diameters. When the user of the bicycle operates the shift lever on the handle, the roller chain is replaced with the sprocket designated by the shift lever. As a result, the rear wheel rotates at a gear ratio corresponding to the diameter of the sprocket. However, in such a general transmission mechanism, the gear ratio can only be switched by the number of steps corresponding to the number of sprockets.

On the other hand, Japanese Patent Application Laid-Open No. 2016-70393 describes a transmission for a bicycle that can continuously change the gear ratio. The transmission disclosed in this publication changes the rotation speed ratio between the first rolling element and the second rolling element by inclining the supporting pins of the planetary rollers arranged around the main shaft.
JP 2016-70393 A

However, in the transmission disclosed in Japanese Patent Application Laid-Open No. 2016-70393, the input-side rolling surfaces of the planetary rollers are conical surfaces. Therefore, the angle of the rolling surface on the input side also changes depending on the inclination angle of the planetary roller. As a result, the direction and magnitude of the pressure applied to the rolling surface on the input side are greatly changed. If the pressure applied to the rolling surface on the input side becomes excessive, the resistance increases and power transmission efficiency tends to decrease. Further, when the pressure applied to the rolling surface on the input side becomes too small, the planetary rollers are likely to slip.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a continuously variable transmission that changes the gear ratio by changing the inclination angle of the planetary rollers so that the direction and magnitude of the pressure generated at the contact point between the planetary rollers and the input rotor are less likely to change. intended to provide

An exemplary first invention of the present application is a continuously variable transmission, comprising: an input rotor that rotates about a main shaft at a pre-speed rotation speed; and an input rotor that rotates about the main shaft at a post-speed speed rotation speed. an output rotating body, a plurality of planetary rollers arranged around the main shaft and capable of rotating about the rotation axis, guide members for limiting the positions of both ends of the rotation shaft, and being rotatable about the main axis. and an annular movable ring that is axially movable, wherein the planetary roller has a spherical first inclined surface that contacts the input rotor and a conical surface that contacts the output rotor. and an annular concave portion or annular convex portion that engages with the movable ring, and the guide member holds both ends of the rotation shaft at different positions in the circumferential direction, Both ends of the shaft are held by the guide member so as to be radially displaceable with respect to the main shaft.

According to the exemplary first invention of the present application, the inclination angle in the cross section including the main axis of the rotation shaft of the planetary roller changes according to the axial position of the movable ring. Then, the contact position of the first slanted surface with respect to the input rotator and the contact position of the second slanted surface with respect to the output rotator change respectively. Thereby, the gear ratio between the input rotor and the output rotor can be switched.

Further, according to the exemplary first invention of the present application, the first inclined surface of the planetary roller is spherical. Therefore, regardless of the inclination angle of the planetary rollers, the direction and magnitude of the pressure generated at the contact point between the first inclined surface and the input rotor are less likely to change.

FIG. 1 is a schematic diagram of a bicycle. FIG. 2 is a longitudinal sectional view of the continuously variable transmission. FIG. 3 is a longitudinal sectional view of the continuously variable transmission. FIG. 4 is a longitudinal sectional view of the 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. FIG. 7 is an exploded sectional view of the planetary roller. FIG. 8 is a diagram showing the pressure generated at 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. FIG. 9 is a diagram showing the pressure generated at 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. FIG. 10 is a diagram showing the pressure generated at 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. FIG. 11 is a diagram showing planetary rollers and a movable ring according to a first modified example. FIG. 12 is a longitudinal sectional view of a continuously variable transmission according to a second modified example. FIG. 13 is a plan view of a first guide plate and a second guide plate according to a second modification, viewed from one side of the main shaft. FIG. 14 is a diagram of a planetary roller according to a second modified example viewed from the outside in the radial direction. FIG. 15 is a longitudinal sectional view of a continuously variable transmission according to a third modified example.

Exemplary embodiments of the invention are described below with reference to the drawings. In the present application, the direction parallel to the main shaft of the continuously variable transmission is referred to as "axial direction", the direction orthogonal to the main shaft is referred to as "radial direction", and the direction along the arc centered on the main shaft is referred to as "circumferential direction". . However, the above-mentioned "parallel direction" also includes substantially parallel directions. Moreover, the above-mentioned "perpendicular direction" also includes substantially perpendicular directions. Further, in the present application, of the axial ends of the member, the end near the sprocket is referred to as "one end", and the end far from the sprocket is referred to as "the other end".

<1. About bicycle>
FIG. 1 is a schematic diagram of a bicycle 100 using a continuously variable transmission 1 according to one embodiment of the invention. As shown in FIG. 1 , this bicycle 100 has front wheels 110 , rear wheels 120 , pedals 130 , roller chains 140 and continuously variable transmission 1 . The continuously variable transmission 1 is mounted inside a hub provided at the center of the wheel 121 of the rear wheel 120 . When the user pedals the pedals 130 in the forward direction, the rotational motion of the pedals 130 is transmitted to the continuously variable transmission 1 via the roller chains 140 . Continuously variable transmission 1 also changes the speed of the rotational motion received from roller chain 140 and transmits it to rear wheel 120 . Rear wheel 120 rotates at a rotation speed changed by continuously variable transmission 1 . Bicycle 100 may have an electric motor for assisting the rotational motion of pedals 130 .

<2. Configuration of Continuously Variable Transmission>
2 to 4 are longitudinal sectional views of the continuously variable transmission 1. FIG. This continuously variable transmission 1 is a mechanism for outputting rotary motion obtained from a roller chain 140 to a rear wheel 120 at a constant speed or by reducing or increasing the speed. FIG. 2 shows a cross section of the continuously variable transmission 1 at constant speed. FIG. 3 shows a cross section of the continuously variable transmission 1 during deceleration. FIG. 4 shows a cross section of the continuously variable transmission 1 during acceleration. As shown in FIGS. 2 to 4, the continuously variable transmission 1 of this 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 operating portion 60, and an output It has a rotating body 70 .

Hollow shaft 10 is a cylindrical member extending along main axis 9 . Metal such as stainless steel is used for the material of the hollow shaft 10, for example. An input rotor 20, a movable ring 50, and an output rotor 70, which will be described later, are supported by the hollow shaft 10 via bearings. When the continuously variable transmission 1 is attached to the bicycle 100, the continuously variable transmission 1 is arranged so that the main shaft 9, which is the central axis of the hollow shaft 10, and the central axis of the rear wheel 120 are aligned.

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

The relay member 22 has a cylindrical portion 221 and a flange portion 222 . The cylindrical portion 221 extends cylindrically in the axial direction around the hollow shaft 10 . The flange portion 222 extends radially outward from the axial end portion of the cylindrical portion 221 . The flange portion 222 is located inside a housing 72 which will be described later. A pair of first bearings 24 are provided between the relay member 22 and the hollow shaft 10 . A ball bearing, for example, is used for the first bearing 24 . The relay member 22 is rotatably supported 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 engages with multiple teeth provided on the outer peripheral surface of the sprocket 21 . When the bicycle 100 is running, as the roller chain 140 rotates, the sprocket 21 and the relay member 22 rotate about the main shaft 9 at the pre-shift speed. Below, the rotation speed of the sprocket 21 and the relay member 22 is called "1st rotation speed."

The pressure regulating cam 23 is a mechanism that generates an axial pressing force against the planetary roller 30 according to the load in the rotational 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 rolling elements 233 . The first cam member 231 and the second cam member 232 are annular members around the main shaft 9 . The first cam member 231 and the flange portion 222 of the relay member 22 are fixed to each other, for example, by screwing. The multiple rolling elements 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. FIG. 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 23a and a plurality of second cam surfaces 23b. The rolling element 233 is accommodated in the space 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 bicycle 100 pedals 130, input rotor 20 rotates in the forward direction. At this time, each rolling element 233 contacts the first cam surface 23a of the first cam member 231 and the first cam surface 23a of the second cam member 232 as shown in FIG. It is displaced in the direction of riding along. Then, the rolling element 233 moves the second cam member 232 away from the first cam member 231 . Therefore, the contact pressure between the second cam member 232 and the later-described first inclined surface 301 of the planetary roller 30 increases.

On the other hand, when the user of the bicycle 100 rotates the pedals 130 in the opposite direction or at a lower speed than the rear wheel 120, the input rotor 20 also rotates in the opposite direction. At this time, each rolling element 233 contacts the second cam surface 23b of the first cam member 231 and the second cam surface 23b of the second cam member 232, as shown in FIG. As a result, the rolling element 233 moves the first cam member 231 without changing 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 and axial directions. and the second cam member 232 rotate integrally. Therefore, the contact pressure between the second cam member 232 and the later-described first inclined surface 301 of the planetary roller 30 is weakened. As a result, the input rotor 20 and the output rotor 70 idle. In other words, the pressure regulating cam 23 can cause the continuously variable transmission 1 to function as a one-way clutch.

A thrust bearing 25 is provided between the first cam member 231 of the pressure adjusting cam 23 and a housing 72 which will be described later. A needle bearing, for example, is used for the thrust bearing 25 . The first cam member 231 and the housing 72 are rotatable relative to each other via the thrust bearing 25 . Thereby, the input rotor 20 and the output rotor 70 can be rotated at different rotation speeds.

A plurality of planetary rollers 30 are arranged around the main shaft 9 . Each planetary roller 30 is rotatably supported around a swingable rotation shaft 300 . As shown in FIGS. 2-4, the surface of each planetary roller 30 has a first inclined surface 301, a second inclined surface 302, and an annular recess 303. As shown in FIGS. The first inclined surface 301 is a hemispherical (spherical) surface whose diameter gradually expands as it moves away from one end of the rotation axis 300 and whose center is near the center of the rotation axis 300 . The first inclined surface 301 contacts the second cam member 232 . The second inclined surface 302 is a conical surface that gradually expands in diameter as it separates from the other end of the rotation axis 300 . The second inclined surface 302 contacts the contact member 71 of the output rotor 70, which will be described later.

The annular recessed portion 303 is an annular groove centered on the rotation axis 300 . The annular recess 303 is positioned between the first slanted surface 301 and the second slanted surface 302 . As shown in FIGS. 2 to 4, the shape of the annular recess 303 is substantially arcuate in a cross section including the main shaft 9. As shown in FIGS. An annular projection 51 of the movable ring 50 , which will be described later, contacts the annular recess 303 .

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

7 is an exploded sectional view of the planetary roller 30. FIG. As shown in FIG. 7, the planetary roller 30 of this 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 recessed portion 303 . When combining the first planetary member 31 and the second planetary member 32 , for example, the cylindrical protrusion 304 provided on the second planetary member 32 is press-fitted into the first planetary member 31 . However, the method of fixing the first planetary member 31 and the second planetary member 32 may be another method such as welding.

Planetary rollers 30 preferably have cavities 33 inside for weight reduction. By combining the first planetary member 31 and the second planetary member 32 as in this embodiment, the planetary roller 30 having the cavity 33 inside can be easily formed.

Further, 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. By doing so, it is possible to suppress the occurrence of minute steps on the surface of the annular recess 303 . That is, the dimensional accuracy of the annular recess 303 can be improved. Also, the rigidity of the annular concave portion 303 can be increased. Therefore, the annular convex portion 51 of the movable ring 50, which will be described later, can be brought into contact with the annular concave portion 303 with high accuracy. Note that the annular recess 303 may belong to the first planetary member 31 .

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 are non-rotatable 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 positioned on both sides of the planetary roller 30 in the axial direction. Also, the first guide plate 41 and the second guide plate 42 expand radially outward with respect to the main shaft 9 .

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

One end of the rotation shaft 300 is radially displaceable along the first notch 410 . Also, the other end of the rotation shaft 300 is radially displaceable along the second notch 420 . As will be described later, both ends of the rotation shaft 300 are radially displaced according to the axial position of the movable ring 50 . As a result, the inclination angle of the rotation axis 300 within the cross section including the main axis 9 changes. Inclination of the rotation shaft 300 of the planetary roller 30 with respect to the main shaft 9 due to the position of both ends of the rotation shaft 300 being displaced in the radial direction is hereinafter referred to as “radial inclination”. .

The movable ring 50 is an annular member positioned radially outside the hollow shaft 10 and radially inside the planetary rollers 30 . The movable ring 50 has an annular protrusion 51 protruding radially outward. As shown in FIGS. 2 to 4, the annular projection 51 has a substantially arcuate shape in a cross section including the main shaft 9. As shown in FIGS. The annular projection 51 fits into the annular recess 303 of the planetary roller 30 . Thereby, the movable ring 50 and the planetary roller 30 are engaged.

Movable ring 50 is supported by hollow shaft 10 via engaging member 81 and second bearing 82 . A ball bearing, for example, is used for the second bearing 82 . The movable ring 50 is fixed to the outer ring of the second bearing 82 . Therefore, the movable ring 50 can rotate relative to the hollow shaft 10 and the engaging member 81 around the main shaft 9 .

Further, 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 fixed to the inner ring of the second bearing 82 and axially slidably engages with the slit 11 . Therefore, the engaging member 81, the second bearing 82, and the movable ring 50 can move axially along the slit 11 as a unit.

The operation part 60 is a mechanism for switching the axial position of the movable ring 50 . As shown in FIGS. 2 to 4, the operating section 60 has a rod 61 and a wire mechanism 62. As shown in FIGS. The rod 61 is a cylindrical member inserted inside the hollow shaft 10 . Rod 61 extends axially along main axis 9 . A wire 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 . A user of the bicycle 100 can change the axial position of the rod 61 by operating the wire mechanism 62 . When the rod 61 moves axially, the engaging member 81 , the second bearing 82 and the movable ring 50 also move axially along the slit 11 . As the movable ring 50 moves in the axial direction, the engagement position between the annular projection 51 and the annular recess 303 also changes in the axial direction. As a result, the radial inclination angle of the planetary rollers 30 changes.

However, the operating portion 60 may be implemented by other mechanisms such as screws that are axially positionable.

The output rotor 70 rotates around the main shaft 9 at the post-speed rotation speed. Below, the rotation speed after shifting is called "2nd rotation speed." As shown in FIGS. 2-4, the output rotor 70 of this embodiment has 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 contacts the second inclined surface 302 of the planetary roller 30 . The housing 72 is an annular housing that accommodates the pressure regulating cam 23 , the plurality of planetary rollers 30 , the guide member 40 and the movable ring 50 inside. Housing 72 is supported by hollow shaft 10 via third bearing 73 . Also, the housing 72 is supported by the relay member 22 via a 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 as the planetary roller 30 rotates, the contact member 71 and the housing 72 also rotate about the main shaft 9 at the second rotation speed. Also, the housing 72 is fixed to a hub provided in 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. Regarding shifting operation>
Next, the speed change operation of the above-described continuously variable transmission 1 will be described.

When the power obtained from the roller chain 140 rotates the input rotating body 20 at the first rotational speed, the second cam member 232 of the pressure adjusting cam 23 also contacts the first inclined surface 301 of the planetary roller 30 and rotates at the first rotational speed. Rotate at rpm. Then, the planetary roller 30 rotates around the rotation axis 300 due to the frictional force between the second cam member 232 and the first inclined surface 301 . Also, the frictional force between the second inclined surface 302 and the contact member 71 causes the output rotor 70 to rotate at the second rotation speed.

Here, as described above, in this embodiment, the user of the bicycle 100 can change the radial inclination angle of the planetary rollers 30 by operating the operation unit 60 .

For example, as shown in FIG. 3 , when the planetary rollers 30 are radially inclined so that one end of the rotation shaft 300 approaches the main shaft 9 , the portion of the first inclined surface 301 that contacts the input rotor 20 does not rotate. The distance from axis 300 increases. Then, the distance from the rotation axis 300 to the portion of the second inclined surface 302 that contacts the output rotor 70 is reduced. Therefore, the second rotation speed, which is the rotation speed of the output rotor 70 , is smaller than the first rotation speed, which is the rotation speed of the input rotor 20 . That is, the rotational motion of the input rotor 20 is decelerated and output from the output rotor 70 to the rear wheels 120 .

On the other hand, as shown in FIG. 4, when the planetary rollers 30 are radially inclined so that one end of the rotation shaft 300 moves away from the main shaft 9, the portion of the first inclined surface 301 that contacts the input rotor 20 is The distance from axis 300 becomes smaller. Then, the distance from the rotation axis 300 to the portion of the second inclined surface 302 that contacts the output rotor 70 increases. Therefore, the second rotation speed, which is the rotation speed of the output rotation member 70 , is greater than the first rotation speed, which is the rotation speed of the input rotation member 20 . That is, the rotational motion of the input rotor 20 is accelerated and output from the output rotor 70 to the rear wheels 120 .

As described above, 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 axis 9 changes according to the axial position of the movable ring 50 . Then, the contact position of the first inclined surface 301 with respect to the input rotating body 20 and the contact position of the second inclined surface 302 with respect to the output rotating body 70 respectively change. Thereby, the gear ratio between the input rotor 20 and the output rotor 70 can be switched.

8 to 10 show the pressure F1 generated at the contact point between the second cam member 232 and the first inclined surface 301 and the pressure F2 generated at the contact point between the contact member 71 and the second inclined surface 302. is. 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, the inclination angle of the first inclined surface 301 at the point of contact between the second cam member 232 and the first inclined surface 301 is constant regardless of the radial inclination angle of the planetary rollers 30 . Therefore, the direction of the pressure F1 generated at the contact point is also constant regardless of the inclination angle of the planetary roller 30 in the radial direction. Therefore, if the torque input to the input rotor 20 is constant, as shown in FIGS. 8 to 10, the pressure generated at the contact point is The size of F1 does not change.

If the pressure F1 becomes too small, slippage is likely to occur between the second cam member 232 and the first inclined surface 301 . Further, when the pressure F1 becomes excessive, excessive rolling resistance is generated between the second cam member 232 and the first inclined surface 301, and power transmission efficiency tends to decrease. Also, if the pressure F1 becomes excessive, the second cam member 232 or the first inclined surface 301 is likely to be damaged. These problems can be solved by making the pressure F1 constant regardless of the radial inclination angle of the planetary rollers 30 as in the present embodiment.

It should be noted that the shape of the first inclined surface 301 does not have to be strictly a spherical shape. That is, the "spherical shape" in the present invention also includes a substantially spherical shape. Also, 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 constant. It suffices if the first inclined surface 301 is "spherical" so as to suppress changes 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 point of contact between the contact member 71 and the second inclined surface 302 changes according to the radial inclination angle of the planetary rollers 30. . Therefore, the direction of the pressure F2 generated at the contact point also changes according to the inclination angle of the planetary roller 30 in the radial direction. Therefore, as shown in FIG. 9, the pressure F2 during deceleration is greater than the pressure F2 during constant velocity. Further, as shown in FIG. 10, the pressure F2 during acceleration is smaller than the pressure F2 during constant speed.

Thus, the pressure F2 corresponding 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 conical second inclined surface 302 receives greater pressure closer to its apex. For this reason, in this embodiment, as shown in FIG. 7, the conical second planetary member 32 is made thicker toward the apex. That is, the axial or radial thickness of the second planetary member 32 increases toward the apex. In this way, deformation of the second planetary member 32 due to load during use can be suppressed. On the other hand, the spherical first inclined surface 301 receives constant pressure regardless of the contact position. For this reason, in this embodiment, as shown in FIG. 7, the thickness of the hemispherical first planetary member 31 in the axial direction or the radial direction is made constant thin.

<4. Variation>
Although exemplary embodiments of the invention have been described above, the invention is not limited to the above embodiments.

<4-1. First modification>
FIG. 11 is a diagram showing a planetary roller 30A and a movable ring 50A according to a first modified example. In the example of FIG. 11 , the axial width d1 of the annular concave portion 303A of the planetary roller 30A is larger than the axial width d2 of the annular convex portion 51A provided on the outer peripheral portion of the movable ring 50 . 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. By doing so, the contact between the planetary roller 30A and the movable ring 50A is one point, and the rolling resistance is reduced. In addition, corners located at both ends in the axial direction of the annular recess 303A do not contact the movable ring 50A. Therefore, contact resistance between the planetary roller 30A and the movable ring 50A can be reduced.

<4-2. Second modification>
FIG. 12 is a longitudinal sectional view of a continuously variable transmission 1B according to a second modification. In the example of FIG. 12, a 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. A free end, which is one axial end of the coil spring 90B, contacts the engaging member 81B. A positioning member 12B is arranged inside the hollow shaft 10B. A fixed end, which is the other axial end of the coil spring 90B, contacts the positioning member 12B. In this manner, the coil spring 90B is arranged between the positioning member 12B and the engaging member 81B in a state compressed to a length greater than its 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 axial end side to the engaging member 81B, the second bearing 82B, and the movable ring 50B.

FIG. 13 is a plan view of the first guide plate 41B and the second guide plate 42B according to the second modification, viewed from one side of the main shaft 9B. FIG. 14 is a view of the planetary roller 30B according to the second modification as seen from the radially outer side. Also in this modification, the first guide plate 41B has a plurality of first notches 410B. Also, the second guide plate 42B 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 and the position of the second notch 420B in the circumferential direction with respect to the main shaft 9B are slightly different. differ. Therefore, as shown in FIG. 14, both ends of the rotating shaft 300B are held at different positions in the circumferential direction by the first guide plate 41B and the second guide plate 42B. Such a state in which both ends of the rotation shaft 300B have different positions in the circumferential direction is hereinafter referred to as a "circumferentially inclined state". The planetary rollers 30B are always supported in a circumferentially inclined state.

When the power obtained from the roller chain rotates the input rotor 20B at the first rotation speed, the second cam member 232B of the pressure regulating cam 23B also contacts the first inclined surface 301B of the planetary roller 30B to perform the first rotation. Rotate by number. Then, the planetary roller 30B rotates around the rotation axis 300B due to the frictional force between the second cam member 232B and the first inclined surface 301B. Also, the frictional force between the second inclined surface 302B and the contact member 71B causes the output rotor 70B to rotate at the second rotation speed. At this time, as indicated by an arrow in FIG. 14, the second inclined surface 302B of the planetary roller 30B applies a tangential force Fo proportional to the torque to the contact member 71B.

Here, the planetary rollers 30B are supported while being inclined in the circumferential direction as described above. Therefore, the force Fo generates a force component Fa in the circumferential direction around the rotation axis 300B and a force component Fb in a direction parallel to the rotation axis 300B. Assuming that 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 satisfies 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 from the contact member 71 a reaction force Fc having the same magnitude as the component force Fb. This reaction force Fc acts to radially incline the rotation shaft 300B of the planetary roller 30B so that one end of the rotation shaft 300B (the end on the input rotor 20B side) approaches 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 the axial direction away from the positioning member 12B. Therefore, as shown in FIG. 12, the planetary roller 30B receives an axial force Fd from the movable ring 50B. This force Fd acts to radially incline the rotation shaft 300B so that one end of the planetary roller 30B is separated from the main shaft 9B. In addition, as one end of the rotation shaft 300B of the planetary roller 30B inclines closer to the main shaft 9B, the coil spring 90B is compressed and the force Fd increases.

In this way, when a load is applied to the input rotor 20B, two forces Fc and Fd are applied to the planetary roller 30B to tilt the rotation shaft 300B in opposite radial directions. The rotation axis 300B stops at an inclination angle that balances these forces Fc and Fd. Then, the planetary roller 30B rotates around the rotation axis 300B of the inclination angle.

For example, when the load is large (when the force Fo is strong), the force component Fb of the force Fo also increases. Therefore, the reaction force Fc of the force component Fb also increases. Therefore, the planetary rollers 30B are radially inclined so that one end of the rotation shaft 300B approaches the main shaft 9B. In that case, the rotational motion of the input rotor 20B is decelerated and output from the output rotor 70B to the rear wheels. On the other hand, when the load is small (when the force Fo is weak), the force component Fb of the force Fo is also small. Therefore, the reaction force Fc of the force component Fb is also reduced. Therefore, the planetary rollers 30B are radially inclined such that one end of the rotation shaft 300B moves away from the main shaft 9B. In this case, the rotational motion of the input rotor 20B is accelerated and output from the output rotor 70B to the rear wheels.

Thus, in the continuously variable transmission 1B of FIG. 12, the radial inclination angle of the rotation shaft 300B of the planetary roller 30B changes according to the load applied to the planetary roller 30B. Therefore, the gear ratio between the input rotor 20B and the output rotor 70B can be automatically switched according to the load.

In addition, 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 axial positions of the rod 61 and the positioning member 12B by operating the operating 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. Then, the pressure applied from the coil spring 90B to the engaging member 81B, the second bearing 82B, and the movable ring 50B changes. That is, Fd mentioned above changes. Therefore, the relationship between the load and the gear ratio can be adjusted.

For example, when the position of the positioning member 12B in the axial direction is changed in the direction of approaching the input rotor 20B, the force Fd described above increases. Therefore, it becomes easier to accelerate the rotational motion of the input rotor 20B. On the other hand, when the axial position of the positioning member 12B is changed in the direction away from the input rotor 20B, the aforementioned force Fd becomes smaller. Therefore, it becomes easier to decelerate the rotational motion of the input rotor 20B.

<4-3. Third modification>
FIG. 15 is a longitudinal sectional view of a continuously variable transmission 1C according to a third modified example. A continuously variable transmission 1C of FIG. 15 has a solid input shaft 10C instead of the hollow shaft 10 of the above embodiment. A first cam member 231C of the pressure regulating cam 23C is fixed to the input shaft 10C without interposing a relay member. Also, the second cam member 232C of the pressure adjusting cam 23C contacts the first inclined surface 301C of the planetary roller 30C radially inside the rotation shaft 300C.

Further, in the example of FIG. 15, the output rotor 70C has a contact member 71C and an output shaft 73C. The contact member 71C contacts the second inclined surface 302C of the planetary roller 30C radially inside the rotation shaft 300C. The output shaft 73C extends along the main axis 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 positioned radially outward of the planetary rollers 30C. The movable ring 50C has an annular protrusion 51C protruding radially inward. The annular projection 51C fits into the annular recess 303C of the planetary roller 30C. Thereby, the movable ring 50C and the planetary roller 30C are engaged. Also, the movable ring 50C is slidably supported in the circumferential direction by an engaging member 81C. Also, the movable ring 50C and the engaging member 81C can move in the axial direction along a guide portion (not shown). The user can switch the axial position of the movable ring 50C by operating the operating portion 60C connected to the engaging member 81C.

<4-4. Other Modifications>
In the above-described embodiment, of the input rotor and the output rotor, only the input rotor is provided with the pressure regulating cam. However, the output rotor may also be provided with a pressure regulating cam.

Further, in the above embodiment, the planetary roller has an annular recess, and the movable ring has an annular protrusion that fits into the annular recess. However, the planetary rollers may have annular projections and the movable ring may have annular recesses. Further, a structure 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 that case, if the planetary roller is formed of two members, it is preferable that the entire annular projection belongs to one of the two members.

Also, in the above embodiment, a continuously variable transmission for a bicycle has been described. However, continuously variable transmissions having equivalent structures may be used for applications other than bicycles. For example, a continuously variable transmission having an equivalent structure may be mounted on a tricycle, wheelchair, trolley, automated guided vehicle, robot, or the like.

Also, the shape of the details of the continuously variable transmission and the bicycle may be different from the shapes shown in the drawings of the present application. Also, the elements appearing in the above embodiments and modifications may be appropriately combined as long as there is no contradiction.

This application claims priority based on Japanese Patent Application No. 2017-210368 filed on October 31, 2017, and incorporates all the descriptions described in the Japanese application.

INDUSTRIAL APPLICABILITY The present invention can be used for continuously variable transmissions and bicycles.

Reference Signs List 1, 1B, 1C continuously variable transmission 9, 9B, 9C main shaft 10, 10B hollow shaft 20, 20B input rotor 21 sprocket 22 relay member 23, 23B, 23C pressure adjusting cam 23a first cam surface 23b second cam surface 30 , 30A, 30B, 30C planetary roller 31 first planetary member 32 second planetary member 33 cavity 40 guide member 41, 41B first guide plate 42, 42B second guide plate 50, 50A, 50B, 50C movable ring 51, 51A, 51C annular protrusion 60, 60B, 60C operating portion 70, 70B, 70C output rotor 71, 71B, 71C contact member 72 housing 81, 81B, 81C engagement member 90B coil spring 100 bicycle 110 front wheel 120 rear wheel 121 wheel 130 pedal 140 Roller chain 231, 231C First cam member 232, 232B, 232C Second cam member 233 Rolling element 300, 300B, 300C Rotation shaft 301, 301B, 301C First inclined surface 302, 302B, 302C Second inclined surface 303, 303A , 303C Annular concave portion 410, 410B First notch 420, 420B Second notch

Claims (19)

A continuously variable transmission,
an input rotating body that rotates around the main shaft at the pre-shift speed;
an output rotor that rotates around the main shaft at a post-speed rotation speed;
a plurality of planetary rollers arranged around the main shaft and capable of rotating about the rotation axis;
a guide member that limits the positions of both ends of the rotation shaft;
an annular movable ring rotatable about the main shaft and axially movable;
with
The planetary roller is
a spherical first inclined surface that contacts the input rotating body;
a conical second inclined surface that contacts the output rotor;
an annular concave portion or an annular convex portion that engages with the movable ring;
has
A continuously variable transmission in which both end portions of the rotation shaft are held by the guide member so as to be displaceable in a radial direction with respect to the main shaft. A continuously variable transmission according to claim 1,
A continuously variable transmission, further comprising an operation unit for switching the axial position of the movable ring. A continuously variable transmission according to claim 1,
further comprising an elastic member that exerts an axial biasing force on the movable ring;
A continuously variable transmission in which the guide member holds opposite ends of the rotation shaft at different positions in the circumferential direction. A continuously variable transmission according to any one of claims 1 to 3,
The movable ring is a continuously variable transmission located radially inside the planetary rollers. A continuously variable transmission according to any one of claims 1 to 3,
The movable ring is a continuously variable transmission positioned radially outward of the planetary rollers. A continuously variable transmission according to any one of claims 1 to 5,
further comprising a shaft extending along the main axis;
A continuously variable transmission in which the input rotor, the output rotor, and the movable ring are each supported by the shaft via bearings. A continuously variable transmission according to claim 6,
The guide member is
a first guide plate fixed to the shaft and having a first notch into which one end of the rotation shaft of the planetary roller is fitted;
a second guide plate fixed to the shaft and having a second notch into which the other end of the rotation shaft of the planetary roller is fitted;
continuously variable transmission. A continuously variable transmission according to any one of claims 1 to 7,
The continuously variable transmission, wherein the annular concave portion or the annular convex portion is positioned between the first inclined surface and the second inclined surface. The continuously variable transmission according to any one of claims 1 to 8,
The planetary roller has the annular recess,
A continuously variable transmission in which an outer peripheral portion of the movable ring contacts a surface forming the annular recess of the planetary roller. A continuously variable transmission according to claim 9,
A continuously variable transmission in which, in a cross section including the main shaft, the radius of curvature of the annular concave portion is larger than the radius of curvature of the outer peripheral portion of the movable ring. A continuously variable transmission according to any one of claims 1 to 10,
The input rotor is
A continuously variable transmission including a pressure regulating cam that generates an axial pressing force on the planetary rollers according to a rotational load. A continuously variable transmission according to claim 11,
The pressure regulating cam is
a pair of annular cam members arranged in the axial direction;
a rolling element interposed between the pair of cam members;
has
Each of the pair of cam members is
a first cam surface that contacts the rolling element when the input rotating element rotates in one direction;
a second cam surface that contacts the rolling element when the input rotating body rotates in the other direction;
has
A continuously variable transmission in which 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. A continuously variable transmission according to claim 12,
The angle of the first cam surface with respect to the circumferential direction is 3° or more and 35° or less,
A continuously variable transmission, wherein the angle of the second cam surface with respect to the circumferential direction is 70° or more and less than 90°. A continuously variable transmission according to any one of claims 1 to 13,
The planetary roller is a continuously variable transmission having a cavity inside. A continuously variable transmission according to claim 14,
The planetary roller is
a first planetary member having the first inclined surface;
a second planetary member having the second inclined surface;
continuously variable transmission. A continuously variable transmission according to claim 15,
The first planetary member has a constant thickness in the axial direction or the radial direction,
The second planetary member is a continuously variable transmission in which the thickness in the axial direction or the radial direction increases toward the vertex of the second planetary member. A continuously variable transmission according to claim 15 or 16,
A continuously variable transmission in which the entirety of the annular concave portion or the annular convex portion belongs to either one of the first planetary member and the second planetary member. A continuously variable transmission according to any one of claims 1 to 17,
A continuously variable transmission used in bicycles. A bicycle using the continuously variable transmission according to claim 18.

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