JPH05238468A - Speed change gear for bicycle - Google Patents

Abstract

PURPOSE:To improve the durability with simple operation by fixing a carrier to a crankshaft, arranging plural planetary gears on the same circumference of the carrier, providing a driven rotational body interlocking with the planetary gears, and providing plural one-way clutches selectively outside the planetary gears through plural internal gears meshing with respective planetary gears. CONSTITUTION:When a wire 32 is pulled in the direction of the arrow A by speed change operation, claws 21-23 are engaged with tooth 17a-19a of internal gears 17-19. For example, when the wire is pulled up to a maximum, the claw 23 is engaged with only the ratchet tooth 19a. Thus, only a one-way clutch between the internal gear 19 and a fixed cylinder body 11 is connected. When a crank arm 9 is rotated in the direction of the arrow C in this state, a planetary gear 13 revolves in the specified direction through a crank shaft 6, a planet carrier 12, a shaft 14, a collar 14a, and since only the internal gear 19 is operated by the one-way clutch, a planetary gear 13c is rotated to rotate planetary gears 13a-13b. Thus, a chain 33 is rotated through a sprocket 15b.

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 mechanism 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, but it is not widely used. Further, as a transmission 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 in which a planetary gear mechanism and an external transmission are combined as disclosed in Japanese Utility Model Application Laid-Open No. 50-26547.

[0003]

DISCLOSURE OF THE INVENTION The present invention is described in the above-mentioned JP-A-62.
-99293 relates to a transmission in which a planetary gear mechanism is incorporated in a crankshaft like the transmission of No. 99293, and aims to provide a better transmission by solving the problems of the conventional device. is there. That is, the transmission of JP-A-62-99293 proposed by the present applicant is different from the commonly used multi-stage external transmission and has a linear transmission path orthogonal to the crankshaft at any speed. Since it is transmitted by the power transmission, it is provided to the user as a bicycle transmission that is efficient and has excellent durability without exerting excessive force on the chain or sprocket.

However, it has been found that the conventional device has the following drawbacks. That is, since the one-way clutch for shifting in the device is configured to be provided on the inner peripheral portion of the sun gear, the lever ratio to the crank arm becomes large because the distance from the shaft center is very short, and as a result, the pedal When a pedaling force is applied to the one-way clutch, a large load is applied to these one-way clutches, so there is a problem that the durability of the ratchet, claws, etc. that make up the one-way clutch is impaired. It turns out that the gear shifting operation becomes heavy when performing.
Further, since the device adopts a planetary gear mechanism that can obtain a speed-up, neutral, and deceleration state, the outer size of the device itself becomes large to obtain a gear ratio suitable for traveling of a bicycle, and There was also room for improvement in terms of appearance.

Further, Japanese Patent Laid-Open No. 1-266089 and Japanese Utility Model Laid-Open No. 50-265.
No. 47 publication (the former shows two sprockets, but the latter does not specify the speed change method), that is, a plurality of rows on the output side of the planetary speed increasing mechanism. In the case of a mechanism that has a sprocket and uses an external transmission (derailleur) to change the chain by shifting the chain, it requires an external transmission or multiple sprockets, which causes an increase in weight and cost. It was. In addition, these devices have a structure in which the chain is slid over, so there is a problem that the chain and sprocket are twisted, and in addition, the planetary gear has a cantilever structure, which reduces efficiency and durability. I was invited.

[0006]

In order to solve the above problems, in the present invention, a carrier is fixed to a crankshaft which is rotatably supported by being inserted through a hanger portion of a bicycle frame, and the carrier has the same circle. A plurality of planetary gears, each having a different number of teeth, are integrally rotatably mounted on the circumference, and a driven rotating body integrally formed with a sun gear and a sprocket is provided inside the planetary gear. A plurality of internal gears that mesh with the planetary gears are independently rotatably arranged side by side on the outside of the planetary gears, and a fixed cylinder that covers the outer periphery is fixed to the bicycle frame. And a one-way clutch is interposed between the internal gear and the fixed cylinder, and one of these one-way clutches can be selectively connected to form a bicycle transmission. .

As the one-way clutch described above, ratchet teeth are engraved on the outer periphery of the internal gear, and an opening is provided on the outer periphery of the fixed cylinder, and a pawl in which a pawl is rotatably attached to the pawl is provided. The table is fixed, the pawl is engaged with the ratchet by a spring, and one of the pawls can be selectively connected by operating an operation wire connected to the other end of the pawl. ..

[0008]

Since the device of the present invention is configured as described above, it is possible to perform multi-speed shifting of two or more steps, and the structure of the entire transmission can be made thin and small in diameter without any practical problems. Also,
According to the present invention, since the one-way clutch is provided on the outer peripheral portion of the large-diameter internal gear, the torque due to the pedaling force applied to the one-way clutch can be suppressed low. Therefore, according to the present invention, it is possible to easily put into practical use a bicycle gearbox having two or more gear stages without the need to re-chain.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the figure, 1 (see FIG. 2) is a main pipe of a bicycle frame, 2 is a standing pipe, 3 is a chain stay, 4 (see FIG. 1) is a hanger pipe, 5 is a hanger one screwed to the hanger pipe 4, and 6 is a hanger pipe 4. A crankshaft rotatably provided via a ball bearing 7 and a hanger one 5, 9 is a crank arm fitted to the crankshaft 6, and 10 is a nut with a washer for fitting the crankarm 9 to the crankshaft 6. .. Reference numeral 11 is a hollow disk-shaped fixed cylinder body which is fixed to the end of the hanger pipe 4 with a ring nut 8 and fixed integrally with the frame.

In this embodiment, as shown in FIG. 1, the center hole of the fixed cylinder 11 is fitted to the hanger one 5 screwed to the hanger pipe 4, and the ring nut 8 is fastened to the end of the hanger pipe 4. And fix it integrally with the frame. or,
As shown in a perspective view in FIG. 3, the spline of the crankshaft 6
The carrier body 12b is formed by recessing three portions of the circumference of a disk body having a spline hole 12a that fits with the 6a in a substantially semicircular shape.
The carrier 12 is formed by applying two ring plates 12c and 12d to both sides of the carrier body 12b and fixing them integrally with the carrier body 12b by three bolts 12e.

The carrier 12 is fixed to the crankshaft 6 by fitting the spline hole 12a of the carrier 12 formed as described above into the spline 6a of the crankshaft 6, and the carrier 12 is provided in the recessed portions 12f. A planetary gear 13 is arranged and is rotatably supported on a carrier 12 by a shaft 14. This planetary gear 13 is formed by integrally forming a plurality of gears 13a, 13b, 13c having different numbers of teeth (three in this embodiment), each of which is provided with a carrier 12 by a shaft 14 via a collar 14a.
Is pivoted to.

Further, the sun gear 15a of the driven rotor 15 formed by integrally forming the sun gear 15a and the sprocket 15b is meshed with the planetary gear 13a, and the roller bearing is also used.
It is rotatably fitted to the crankshaft 6 via 16. on the other hand,
Between the gears 13a, 13b, 13c of the planetary gear 13 and the fixed cylinder 11, there are provided internal gears 17, 18, 19 having internal teeth on the inner circumference and ratchet teeth engraved on the outer circumference. , And meshes with the planetary gears 13a, 13b, 13c, respectively. A one-way clutch is interposed between the fixed cylinder 11 and the internal gears 17, 18, and 19, respectively.

That is, 17b (18b, 19b) in FIGS. 4 to 6 are ratchet teeth formed on the outer periphery of the internal gear 17 (18, 19), 21
(22, 23) are claws provided on the fixed cylindrical body 11 via the claw base 20 so as to be disengageable with the ratchet teeth, and 24 (25, 26) are claws 21 (22, 2
3) is a spring for urging the ratchet teeth 17b (18b, 19b) to engage with each other. Ie these ratchet teeth
A one-way clutch is formed by 17b (18b, 19b), claws 21 (22, 23) and springs 24 (25, 26).

Further, in the present invention, one of the above-mentioned plural sets of one-way clutches can be selectively connected. Specifically, as shown in the present embodiment, the nail 21, the nail 21,
22 and 23 and springs 25 and 26 are inserted and rotatably mounted by the pawl shaft 27 (see FIG. 6), and the opening (see FIGS. 2, 4 and 5) provided in the fixed cylinder 11 is inserted through the inside. Tooth gear 17, 18, 19
Ratchet teeth 17b, 18b, 19b engraved on claws 21, 22, 23
The claw base 20 is fixed to the fixed cylinder 11 with screws 29 and 30 so that they are engaged with each other. That is, the claw 23 and the spring 26, and the claw 23
The spring 25 is biased to 22 and the spring 24 is stretched between the claw 21 and the claw base 20, and the claws 21, 22 and 23 are ratchet teeth 17b, 18b,
A one-way clutch is formed by biasingly engaging each of 19b.

A trigger 28 is provided at one end of the pawl 22 so that the pawl 21 moves in the direction A shown in FIGS. 2 and 4 and moves integrally with the pawl 22 when a certain range is exceeded. (See FIG. 5). Further, the pawl 23 is constantly urged by the spring 26 so as to be engaged with the ratchet teeth 19b. Also, the nail 21
A wire nipple receiver 21a is provided at one end of
A wire nipple 32a provided at one end of the operation wire 32 there
Fit. Then, connect the operation wire 32 to the arrows A and B in FIG.
The nail is selected by operating in the same manner as. 31
Is a cover plate provided at the open end of the fixed cylinder 11.

Next, the operation of the device of the present invention configured as described above will be described. When the gear shift operating device (not shown) is operated to pull the operating wire 32 in the direction of the arrow A in FIG. 2 to the maximum extent, the relationship between the pawl and the ratchet tooth becomes the state of FIG. 5 (a). That is, in this case, only the claw 23 and the ratchet tooth 19b are engaged. Therefore, only the one-way clutch between the internal gear 19 and the fixed cylinder 11 is connected.

In this state, when the crank arm 9 is rotated in the direction of arrow C in FIG. 2, the crank shaft 6 and the planet carrier are
The planetary gear 13 revolves in the direction of arrow D in FIG. 4 via the shaft 12, the shaft 14 and the collar 14a. In this case, since only the internal gear 19 is prevented from rotating in the direction of arrow G by the one-way clutch, the planetary gear 13c meshing with the internal gear 19 rotates in the direction of arrow E. The planetary gears 13a and 13b are integrally formed with the planetary gear 13c, and the planetary gears 13a and 13b are
Although 3b meshes with the internal gears 17 and 18, respectively, the internal gears 17 and 18 can rotate freely, and therefore rotate in the same direction and at the same angular velocity as the planetary gear 13c. Therefore, the sun gear 15a meshing with the planetary gear 13a is accelerated in the arrow F direction to rotate. This rotation causes the sprocket 15b integrally formed with the sun gear 15a to rotate, so that the bicycle travels via the chain 33.

Next, when the operation wire 32 is loosened further in the direction of arrow B in FIG. 2 from the state of FIG. 5 (a), the relationship between the pawl and the ratchet tooth becomes the state of FIG. 5 (b). That is, in this case, the pawl 23 and the ratchet tooth 19b and the pawl 22 and the ratchet tooth
Two sets of one-way clutches 18b are engaged. Therefore, the internal gears 19, 18 and the fixed cylinder 11 are connected. When the crank arm 9 is rotated in the direction of arrow C in FIG. 2 in this state,
Crankshaft 6, planet carrier 12, shaft 1 as before
4, the planetary gear 13 revolves in the direction of arrow D in FIG. 4 through the collar 14a, but in this case, the internal gears 19 and 18 are prevented from rotating in the direction of arrow G by the one-way clutch, Planetary gear 13c meshing with gears 19 and 18
And the planetary gears 13b each try to rotate in the direction of arrow E. However, the rotation speed of the planetary gear 13b is
It is faster than c, and since the planetary gears 13b and 13c are integrally formed, the internal gear 19 is rotated in the arrow H direction. That is, the rotation of the planetary gear 13 is determined by the gear 13b. Therefore, the sun gear 15a meshed with the planetary gear 13a integrally formed with the planetary gears 13b, 13c and the sprocket 15b integral with the sun gear 15a rotate in the direction of arrow F at a speed further increased than the previous time.

When the operating wire 32 is further loosened in the direction of arrow B in FIG. 2 from the state shown in FIG. 5 (b), the relationship between the pawl and the ratchet teeth becomes the state shown in FIG. 5 (c). That is, in this case, the claws 21, 22, 23 and the ratchet teeth 17b, 18b, 19b
The three sets of one-way clutches are all engaged. Therefore, the internal gears 17, 18, 19 and the fixed cylinder 11 are all connected. When the crank arm 9 is rotated in the direction of arrow C in FIG. 2 in this state, the planetary gear 13 is again moved through the crank shaft 6, the planet carrier 12, the shaft 14 and the collar 14a in the same manner as the previous time. Although it revolves in the direction of D, in this case, since all of the internal gears 17, 18 and 19 are prevented from rotating in the direction of arrow G by the one-way clutch, this internal gear 1
The planetary gears 13a, 13b and 13c meshing with 7, 18 and 19 each try to rotate in the direction of arrow E. However, the rotation speed of the planetary gear 13a is higher than that of the planetary gears 13b and 13c,
Further, since the planetary gears 13a, 13b, 13c are integrally formed, the internal gears 18 and 19 can be rotated in the direction of arrow H. That is, the rotation of the planetary gear 13 is determined by the planetary gear 13a. Therefore, the sun gear 15a meshing with the planetary gear 13a and the sprocket 15b integral with the sun gear 15a rotate in the direction of arrow F at a speed further increased than the previous time.
Conversely, when decelerating, the operating wire 32 is pulled in the direction of arrow A in FIG. That is, in Fig. 5, (c) → (b) → (a)
You can operate like.

[0020]

Since the present invention is configured as described above, it has the following effects. That is, in this device, the one-way clutch can be selected and the gear shifting operation can be performed simply by operating the gear shifting operation lever to pull or return the operating wire, so that the gear shifting operation can be performed easily and reliably. Also, unlike the conventional device (external transmission that has been frequently used, JP-A 1-266089), an external transmission for replacing a plurality of sprockets or chains is not required, so cost and weight can be suppressed. it can. In addition, in any gear, transmission is performed by a linear transmission path that is orthogonal to the crankshaft, and since each gear shaft has a double-supported structure, the transmission efficiency of each gear is excellent and the strength is high. Even so, the structure is reasonably durable.

Further, as a result of providing the one-way clutch for gear shifting on the outer peripheral portion of the device, the distance from the shaft center to the one-way clutch becomes long, so that the torque due to the pedaling force applied to the one-way clutch becomes small. As a result, the durability of the ratchet and the claws that form the one-way clutch is improved, and the gear shift operation is lightened when the pedaling force is applied. In addition, since the present device constitutes a planetary speed increasing mechanism, the outer shape of the device itself can be suppressed to a small size, and it is possible to provide a compact and lightweight bicycle transmission that is excellent in appearance.

[Brief description of drawings]

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

FIG. 2 is a partially cutaway side view thereof.

FIG. 3 is a perspective view of a combined body of a carrier and a planetary gear.

4 is a sectional view taken along line XX of FIG.

5 (a), (b) and (c) are operation state diagrams of the one-way clutch.

FIG. 6 is an exploded perspective view of a one-way clutch unit.

[Explanation of symbols]

 1 Main pipe 2 Vertical pipe 3 Chain stay 4 Hanger pipe 5 Hangawan 6 Crankshaft 7 Ball bearing 8 Ring nut 9 Crank arm 10 Washer nut 11 Fixed cylinder 12 Carrier 12a Spline hole 12b Carrier body 12c Ring plate 12d Ring plate 12e Bolt 12f Recessed portion 13 Planetary gear 13a, 13b, 13c Planetary gear 14 Shaft 15 Driven rotor 15a Sun gear 15b Sprocket 16 Roller bearing 17, 18, 19 Internal gear 17a, 18a, 19a Internal tooth 17b, 18b, 19b Ratchet tooth 20 Claw stand 21, 22, 23 Claw 21a Wire nipple receiver 24, 25, 26 Spring 27 Claw shaft 28 Trigger 29, 30 Screw 31 Cover plate 32 Operating wire 32a Wire nipple 33 Chain

Claims (2)

[Claims] 1. A plurality of gears each having a different number of teeth integrally formed on the same circumference of a carrier, the carrier being fixed to a crank shaft which is rotatably supported by being inserted through a hanger portion of a bicycle frame. A planetary gear is rotatably rotatably mounted, and a driven rotor integrally formed with a sun gear and a sprocket is provided inside the planetary gear so as to mesh with one of the planetary gears, and the planetary gear is provided outside the planetary gear. A plurality of meshing internal gears are installed side by side independently of each other,
A fixed cylinder that covers the outer circumference is fixedly provided on the bicycle frame, and one-way clutches are respectively interposed between the internal gear and the fixed cylinder so that one of these one-way clutches can be selectively connected. A bicycle transmission characterized in that 2. The one-way clutch according to claim 1,
While engraving ratchet teeth on the outer circumference of the internal gear,
An opening is provided on the outer periphery of the fixed cylindrical body, and a claw base in which a claw is rotatably attached is fixed to the opening so that the claw is engaged with the ratchet by a spring, and the other end of the claw is also provided. A transmission for a bicycle, wherein one of the claws can be selectively connected by operating an operation wire connected to the bicycle.