JPH06263080A - Transmission for bicycle - Google Patents

Abstract

PURPOSE:To smoothly rotate the gears and the sprocket of a transmission for bicycle, enable speed change of multiple steps, and improve durability of one-way clutches. CONSTITUTION:A carrier 15 is fixed to a crankshaft 10 penetrating a gear case 4 provided on the hanger part of a bicycle frame. A planetary gear type speed increasing gear is provided between the carrier 15 and the gear case 4. A plurality of stepped planet gears 24 are rotatably fitted on the same circumferece of the annular sun gear 18 of the planetary gear type speed increasing gear. A driven rotor 7 is provided inside the planet gear 24, the sun gear 9 of the driven rotor 7 is engaged with one of the planet gear 24, and a plurality of internal gears 28, 29, 30, 31 engaged with the planet gear are rotatably provided side by side outside the stepped planet gear 24. One-way clutches 32 are provided between these internal gears and the gear case 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bicycle transmission having a planetary gear provided on a crankshaft portion of a bicycle.

[0002]

2. Description of the Related Art A bicycle transmission that is widely used at present is a so-called external transmission that changes a chain spanned between multiple sprockets via a derailleur. In addition to this, there is a so-called internal transmission in which a transmission mechanism is built in the hub of the rear wheels. Further, as a transmission device in which a planetary gear mechanism is incorporated in the crankshaft portion, there is, for example, one disclosed in Japanese Patent Application Laid-Open No. 62-99293 previously proposed by the present applicant, and Japanese Patent Application Laid-Open No. 1-266089. There is also proposed a system combining a planetary gear mechanism and an external transmission as disclosed in Japanese Utility Model Laid-Open No. 50-26547.

[0003]

DISCLOSURE OF THE INVENTION The present invention is described in the above-mentioned Japanese Patent Application Laid-Open No.
The present invention relates to a transmission in which a planetary gear mechanism is incorporated in a crankshaft portion like the transmission of No. 2-99293, and an object thereof is to solve the problems of the conventional device and to provide a better transmission. Is.

That is, unlike the generally used multi-stage external transmission, the transmission of the above-mentioned Japanese Patent Application Laid-Open No. 62-99293 proposed by the present applicant has a linear shape orthogonal to the crankshaft at any speed. Since the power is transmitted through the transmission path, the chain and the sprocket are provided with no excessive force, and are provided to users as an efficient and durable bicycle transmission.

However, it has been found that the conventional device has the following drawbacks. That is, in this device, the one-way clutch for shifting is provided on the inner peripheral portion of the sun gear, so the distance from the shaft center is very close, so the lever ratio becomes large, and when a pedaling force is applied, these one-way clutches are applied. There is a problem that a heavy load is applied to the clutch, the durability of the ratchet and the claws that make up the one-way clutch is impaired, and the gear shifting operation is heavy when the gear shifting operation is performed with the pedaling force applied. I understood.

Further, in a structure in which a transmission having a planetary mechanism and a sprocket are concentrated on one side like this device, the width of the transmission becomes thicker as the number of gears is increased, resulting in a crank There is a problem that the protrusion of the shaft becomes long, the mounting position of the crank protrudes to the outside, the crank shaft bends when a pedaling force is applied to the pedal, the gear meshes poorly, and the efficiency decreases. That is, it is difficult to obtain the required number of gears such as 6 or 8 required for sports cars and currently popular mountain bikes.

Further, it is proposed in Japanese Patent Application Laid-Open No. 1-266089 and Japanese Utility Model Application Laid-Open No. 50-26547 (two sprockets are shown in the former, but the speed change method is not explicitly shown in the latter). Such a mechanism, that is, a mechanism having a plurality of rows of sprockets on the output side of the planetary speed increasing mechanism and changing the chain by changing the chain with an external transmission (derailleur) requires an external transmission,
It is necessary to provide a plurality of sprockets, which causes an increase in weight and an increase in cost. In addition, since the chain is slanted, the chain and the sprocket are twisted, and the planetary gear has a cantilever structure, so that there is a problem that transmission efficiency and durability are reduced.

[0008]

In order to solve the above problems, in the present invention, a gear case also serving as a hanger is provided on a hanger portion of a bicycle frame, and a crankshaft rotatably supported through the gear case. A carrier is fixed to the carrier, a plurality of planet gears are rotatably mounted on the same circumference of the carrier, and a ring-shaped sun gear is provided inside these planet gears so as to mesh with the planet gears. ,
A one-way clutch is provided between the carrier and the sun gear,
An internal gear that meshes with the planetary gear is rotatably provided outside the planetary gear, and a one-way clutch is provided between the internal gear and the gear case so that the internal gear can be selectively connected. On the same circumference of the sun gear, a plurality of stepped planetary gears, each having a different number of teeth, are integrally rotatably mounted, and the sun gear and sprocket are integrated inside these planetary gears. Provide a driven rotating body formed, so that the sun gear of this driven rotating body meshes with one of the planetary gears, on the outside of the stepped planetary gear,
A plurality of internal gears respectively meshing with the planetary gears are independently rotatably provided side by side, and one-way clutches are provided between the internal gears and the gear case, and one of these one-way clutches is provided. The bicycle transmission is configured to be selectively connectable.

In the above-mentioned bicycle transmission,
Instead of providing a one-way clutch between the carrier and the ring-shaped sun gear, a claw barrel may be fixed to the crankshaft or the carrier, and a one-way clutch may be provided between the claw barrel and the ring-shaped sun gear. Good.

Further, ratchet teeth are engraved on the outer circumference of each of the internal gears described above, and an opening is provided on the outer circumference of the gear case, and a pawl interlocking with a cam is freely rotatable corresponding to the ratchet teeth. The pawl mounted on the shaft may be fixed, and the cam may be rotated by operating the operation wire so that the pawl can be selectively engaged with the ratchet teeth.

[0011]

As described above, the device of the present invention is provided with a gear case which also serves as a hanger in the hanger portion of the bicycle frame, and the planetary speed change mechanism is incorporated in this gear case. ) And the width of both supporting points for supporting the planetary speed change mechanism is wide, the gear and the sprocket can smoothly rotate even when the pedaling force is applied to the pedal.

Further, as a result of the above-mentioned structure, 6 to
Multi-speed shifting such as 8-speed shifting is possible, and it can be widely used for sports type bicycles such as mountain bikes. Furthermore, as a result of the structure that a one-way clutch for gear shifting is provided on the outer peripheral part of the device, the distance from the shaft center to the one-way clutch becomes longer, so the torque due to the pedaling force applied to the one-way clutch becomes smaller, and therefore the one-way clutch is reduced. The durability of the ratchet and claws that make up the clutch is improved, and the gear shifting operation is lightened when the pedal force is applied.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. In the figure, 1 is a main pipe of a bicycle frame, 2 is a vertical pipe, 3 is a chain stay, and 4 is a gear case that also serves as a hanger provided on a hanger portion of the bicycle frame.

The gear case 4 is formed by a case body 4a and a case lid 4b, and is formed by 4c, 4d, 4e.
Are respectively boss portions projecting from the outer peripheral portion of the case body 4a, and the main pipe 1, the standing pipe 2 and the chain stay 3 are fitted and connected to the boss portions 4c, 4d and 4e, respectively.

Reference numeral 4f designates a shaft tube portion projecting from the center of the case body 4a. The left hanger one 5 is fitted and held in the shaft tube portion 4f, and the case lid is also provided. A hollow shaft cylindrical driven rotating body 7 is rotatably provided in a center hole 4g of 4b via a ball bearing 6. The driven rotating body 7 also serves as the right hanger one 7a, a sprocket 8 is fixed to the outer side thereof, and a sun gear 9 is integrally formed on the outer peripheral portion of the inner side.

Reference numeral 10 denotes a crankshaft rotatably supported by the above-mentioned hanger ones 5, 7a and a steel ball 11,
Reference numerals 2 and 13 denote oil seals provided between the hanger ones 5 and 7a and the crankshaft 10, and 14 denotes the crankshaft 10.
The crank arms are fitted to both ends of the crank arm.

A substantially disk-shaped carrier 15 is fixed to the crankshaft 10 in the gear case 4. 15a is a carrier 1
The inner peripheral portion 15b is a boss portion that forms the center portion of the crankshaft 5, and is fitted into the serration portion 10a of the crankshaft 10.

On the right end surface of the carrier 15 in FIG. 1, a plurality of planetary gears 16 (three in this embodiment as shown in FIG. 2) are provided on the same circumferentially equidistant position with respect to the carrier 15 by a shaft 17. Pivot freely. Inside the planetary gear 16, a ring-shaped sun gear 18 is attached to the planetary gear 1.
6, and a one-way clutch 19 is provided between the carrier 15 and the sun gear 18.

That is, as shown in FIG. 2, ratchet teeth 18a are engraved on the inner peripheral portion of the sun gear 18, and a boss portion 15a provided on the carrier 15 facing the ratchet teeth 18a.
A plurality of (two in this embodiment) claws 20 are rotatably pivotally attached to the outer peripheral portion of the one-way clutch so that the free ends of the claws 20 are engaged with the ratchet teeth 18a by springs 21. Make up 19.

On the other hand, between the planetary gear 16 and the gear case 4, there is provided an internal gear 22 having internal teeth 22a on its inner circumference and ratchet teeth 22b on its outer circumference. Let it mesh.

Further, a plurality of gears 24a, 24b, 24c, 24d having different numbers of teeth (four in this embodiment) are integrally formed at the same circumferential position of the ring-shaped sun gear 18. The three planetary gears 24 are rotatably supported by the shaft 25 with respect to the sun gear 18. Then, the planetary gear 24d is meshed with the sun gear 9. Again 2
Reference numeral 6 is a ring-shaped shaft support plate provided for supporting the right end of the shaft 25, 27 is a bolt for fixing the shaft support plate 26 to the sun gear 18, and 27a is a collar thereof.

Further, the respective gears 24a, 2 of the planetary gear 24
4b, 24c, 24d and the gear case 4 are provided with internal gears 28, 29, 30, 31 having internal teeth on their inner circumferences and ratchet teeth engraved on their outer circumferences, respectively. It meshes with 24a, 24b, 24c and 24d.

Further, the gear case 4 and the internal gears 22, 28,
A one-way clutch 32 is interposed between 29, 30, and 31. That is, 22a, 28a, 29a, 30a, 3
Reference numeral 1a denotes internal teeth formed on the inner circumference of the internal gears 22, 28, 29, 30, 31 and 22b, 28b, 29b, 30b, 3
1b is a ratchet tooth formed on the outer periphery of the internal gear 22, 28, 29, 30, 31.

Further, an opening 4h is provided on the outer circumference of the case body 4a of the gear case 4, and a substantially box-shaped claw base 37 is fitted therein, and the ratchet teeth 22b, 28 are fitted in the claw base 37.
claws 2 corresponding to b, 29b, 30b and 31b, respectively
3,33,34,35,36 shaft 38 (see FIGS. 2 and 3)
Is provided rotatably with respect to the nail base 37 by means of these nails 2
A spring 39 (see FIGS. 2 and 3) for urging 3, 33, 34, 35, 36 to engage the corresponding ratchet teeth 22b, 28b, 29b, 30b, 31b is provided on one side of each claw and the claw base. 37, and five cams 40, 41, 42, 43, 4 that come into contact with the other side of each claw.
4 as shown in FIG.
Is fixed to a shaft 45 penetrating therethrough, a wire reel 46 is fixed to an outer protruding portion of the shaft 45, and an operation wire 47 is connected to the wire reel 46. Reference numeral 48 is a return spring for the wire reel 46 fitted on the shaft 45.

7 and 8 show another embodiment of the present invention, in which the same reference numerals as those used in the drawings denote the same elements. That is, in the embodiment of FIG. 1 described above,
The carrier 15 is provided with the boss portion 15a, and the one-way clutch 19 is provided between the outer peripheral portion of the carrier 15 and the inner peripheral portion of the sun gear 18 arranged opposite to the boss portion. However, in the embodiment of FIG. Instead of providing 15a, the claw barrel 49 is fixed to the crankshaft 10, the sun gear 18 is arranged facing it, and the one-way clutch 19 is interposed therebetween.

In the embodiment shown in FIG. 8, the claw barrel 49 is fixed to the outer periphery of the boss portion 15a of the carrier 15, the sun gear 18 is arranged opposite thereto, and the one-way clutch 19 is interposed therebetween. Is.

Next, the operation of the device of the present invention configured as described above will be described. Operate the speed change device (not shown),
When the operating wire 47 is pulled in the direction of the arrow A in FIG. 2 to the maximum extent, the relationship between the claws and the ratchet teeth becomes as shown in column (a) of Table 1 below. In the table, the black circles indicate the ON state in which the pawls are engaged with the ratchet teeth, and the white circles indicate the OFF state in which the pawls are disengaged from the ratchet.

[0028]

[Table 1]

That is, in this case, the pawl 33 is engaged with the ratchet teeth 28b by the rotation of the cam 41, and the one-way clutch 3 is engaged.
Two connect. Therefore, the internal gear 28 and the gear case 4 are connected. In this state, the crank arm 14 is shown in FIG.
When rotated in the direction of arrow B, the crankshaft 10 and the carrier 15 fixed thereto also rotate in the direction of arrow B. Along with this, the planetary gear 1 rotatably supported on the carrier 15
6 also revolves in the direction of arrow B via the shaft 17, but the one-way clutch 32a between the internal gear 22 and the gear case 4 meshing therewith is in the disengaged state, and therefore meshes with the planetary gear 16. The sun gear is not accelerated by the planet gear 16.

However, when the carrier 15 rotates in the direction of arrow B, the one-way clutch 19 interposed between the sun gear 18 and the carrier 15 operates, and the sun gear 18 is integrated with the carrier 15 in the direction of arrow B. Rotate. Therefore, the planetary gear 24 revolves in the direction of arrow C in FIG. 6 via the sun gear 18 and the shaft 25. In this case, since the internal gear 28 is prevented from rotating in the direction of arrow C by the one-way clutch 32, the planetary gear 24a meshing with the internal gear 28 rotates in the direction of arrow D. In addition, the planetary gear 24
b, 24c, 24d are formed integrally with the planetary gear 24a, and the planetary gears 24b, 24c, 24d are meshed with the internal gears 29, 30, 31 respectively, but the internal gears 29, 30, 31 Can rotate freely, so that it rotates in the same direction and at the same angular velocity as the planetary gear 24a.

That is, the rotation of the planetary gear 24 is determined by the rotation of the gear 24.
It depends on a. Therefore, the sun gear 9 meshing with the planetary gear 24d integrally formed with the planetary gear 24a and the sprocket 8 integral with the sun gear 9 are accelerated in the arrow F direction to rotate. Therefore, the rear wheel rotates through the chain (not shown) and the bicycle runs.

When the operating wire 47 is loosened further in the direction of arrow G from the state shown in FIG. 5 (a), the relationship between the pawl and the ratchet tooth becomes as shown in Table 1 (b). That is, in this case, the pawl 34 is engaged with the ratchet teeth 29b by the rotation of the cam 42 to connect the one-way clutch 32. Therefore, the internal gear 29 and the gear case 4 are connected.

When the crank arm 14 is rotated in the direction of arrow B in FIG. 2 in this state, the crank shaft 10 and the carrier 15 fixed to the crank shaft 10 also rotate in the direction of arrow B as in the previous case. Accordingly, the planetary gear 16 rotatably supported on the carrier 15 also revolves in the direction of arrow B via the shaft 17, but the one-way clutch 32a between the internal gear 22 and the gear case 4 meshing with the planetary gear 16 is disengaged. Therefore, the sun gear 18 meshing with the planetary gear 16 is
Is not accelerated by.

However, when the carrier 15 rotates in the direction of arrow B, the one-way clutch 19 interposed between the sun gear 18 and the carrier 15 operates, and the sun gear 18 is integrated with the carrier 15 in the direction of arrow B. Rotate. Therefore, the planetary gear 24 revolves in the direction of arrow C in FIG. 6 via the sun gear 18 and the shaft 25. In this case, since the internal gear 29 is prevented from rotating in the direction of arrow C by the one-way clutch 32, the planetary gear 24b meshing with the internal gear 29 rotates in the direction of arrow D. In addition, the planetary gear 24
a, 24c, 24d are formed integrally with the planetary gear 24b, and the planetary gears 24a, 24c, 24d are meshed with the internal gears 28, 30, 31 respectively, but the internal gears 28, 30, 31 Can rotate freely, and therefore rotates in the same direction and at the same angular velocity as the planetary gear 24b. That is, the rotation of the planetary gear 24 is determined by the gear 24b.
Therefore, the planetary gear 2 integrally formed with the planetary gear 24b
The sun gear 9 meshing with 4d and the sprocket 8 integrated with the sun gear 9 rotate in the direction of arrow F at a speed further increased than the previous time.

Similarly, when the gear shift operating device is operated and the operating wire is returned step by step, the speed is further increased accordingly. In particular, as shown in (e) to (h) of Table 1, in the state where the one-way clutch 32a between the internal gear 22 and the gear case 4 is connected by the pawl 23 engaging with the ratchet teeth 22b. When the crank arm is rotated in the direction of arrow B in FIG. 2, the crankshaft 10 and the carrier 15 fixed thereto also rotate in the direction of arrow B,
Accordingly, the planetary gear 16 rotatably supported on the carrier 15 also revolves in the direction of arrow B via the shaft 17. In this case, since the one-way clutch 32a between the internal gear 22 and the gear case 4 is connected as described above, the planetary gear 16 rotates in the direction of arrow H in FIG. Along with this, the sun gear 18 meshing with the planetary gear 16 is also accelerated and rotated in the direction of arrow B. This rotation is further accelerated by the action of the planetary gear 24 as described above, and the sprocket 8 is rotated.

On the contrary, when decelerating, the operating wire 47 may be pulled in the direction of arrow L in FIG. 5 (d). In this embodiment, the shifting cams 40, 41, 42, 43 and 44 are fixed to the shaft 45 with their phases shifted from each other, and the shifting operation is performed with a single operating wire. 40 is arranged independently of the other cams 41, 42, 43, 44,
Operate the cam 40 by another system to turn the pawl 23 ON and OF
By selecting F, it is possible to select four high speeds and four low speeds for a total of eight speeds. Further, in the present embodiment, although the 8-speed is adopted, it is also possible to develop 6-speed and 10-speed.

[0037]

As described above, the device of the present invention is provided with a gear case also serving as a hanger on the hanger portion of the bicycle frame, and the planetary speed change mechanism is incorporated in this gear case. In addition to being able to be arranged in the central portion), the width of both supporting points for supporting the planetary speed change mechanism is wide, so that the gear and the sprocket can smoothly rotate even if the pedaling force is applied to the pedal. In addition, as a result of the above-mentioned configuration, it is possible to perform multi-speed shifting such as 6-8 speed shifting, and it is possible to widely adopt sports type bicycles such as mountain bikes.

Further, as a result of the structure in which the one-way clutch for speed change is provided on the outer peripheral portion of the device, the distance from the shaft center to the one-way clutch becomes longer, so the torque due to the pedaling force applied to the one-way clutch becomes smaller. Therefore, the durability of the ratchet and the claws that form the one-way clutch is improved, and the gear shifting operation is lightened while the pedaling force is applied. Further, since the shift change device has the ON / OFF structure by the cam, the shift operation is simple and the shift can be surely performed, and the silent transmission in which the contact noise between the pawl and the ratchet is eliminated can be provided. According to it, many excellent effects can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a device of the present invention.

FIG. 2 is a side view including the XX cross section of FIG.

3 is a side view including a YY cross section of FIG. 1. FIG.

FIG. 4 is a perspective view of five cams having different phases.

5 (a) to 5 (h) are explanatory views showing operating states of the one-way clutch.

FIG. 6 is an operation explanatory view of the device of the present invention corresponding to FIG.

FIG. 7 is a vertical sectional view showing another embodiment of the device of the present invention.

FIG. 8 is a vertical sectional view showing another embodiment of the device of the present invention.

[Explanation of symbols]

 1 main pipe 2 vertical pipe 3 chain stay 4 gear case 4a case body 4b case lid 5 hangawan 6 ball bearing 7 driven rotor 8 sprocket 9 sun gear 10 crankshaft 11 steel ball 12, 13 oil seal 14 crank arm 15 carrier 16 planetary gear 17 shaft 18 sun gear 18a ratchet tooth 19 one-way clutch 20 pawl 21 spring 22 internal gear 22a internal tooth 22b ratchet tooth 23 pawl 24 planetary gear 24a, 24b, 24c, 24d gear 25 shaft 26 shaft support plate 27 bolt 28, 29 , 30, 31 Internal gear 28a, 29a, 30a, 31a Internal tooth 28b, 29b, 30b, 31b Ratchet tooth 32 One-way clutch 33, 34, 35, 36 Claw 37 Claw plate 38 Shaft 39 Spring 40, 41, 42, 43, 44 Cam 45 Axis 46 Wire reel 47 Operating wire 48 Return spring 49 Claw barrel

Claims (3)

[Claims] 1. A bicycle frame hanger part is provided with a gear case which also functions as a hanger, and a carrier is fixed to a crankshaft which is rotatably supported by penetrating the gear case, and a plurality of carriers are provided on the same circumference of the carrier. A planetary gear is rotatably attached to the inside of the planetary gear, a ring-shaped sun gear is provided so as to mesh with the planetary gear, and a one-way clutch is provided between the carrier and the sun gear. An internal gear that meshes with the planetary gear is rotatably provided on the outside of the ring gear, and a one-way clutch is provided between the internal gear and the gear case to enable selective connection. A plurality of stepped planetary gears, each of which has a different number of teeth, are integrally rotatably mounted on the same circumference of, and the sun gear and the sprocket are integrated inside the planetary gears. The driven rotor formed is provided so that the sun gear of the driven rotor meshes with one of the planetary gears, and a plurality of internal gears respectively meshing with the planetary gears are provided outside the stepped planetary gear. A bicycle characterized in that they are independently rotatably provided side by side, one-way clutches are provided between these internal gears and the gear case, and one of these one-way clutches can be selectively connected. Transmission. 2. Instead of providing a one-way clutch between the carrier and the ring-shaped sun gear according to claim 1, a claw barrel is fixed to the crankshaft or the carrier, and the claw barrel and the ring-shaped sun gear are provided. A bicycle transmission characterized in that a one-way clutch is provided between the two. 3. The ratchet teeth are engraved on the outer circumference of each internal gear according to claim 1, and an opening is provided on the outer circumference of the gear case, which corresponds to the ratchet teeth.
Fix the claw stand that pivotally attaches the claw that interlocks with the cam,
A bicycle transmission, wherein the cam is rotated by operating an operation wire so that the pawl can be selectively engaged with the ratchet teeth.