JPH0331630B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a transmission device provided on the crankshaft of a bicycle.

(Prior Art) A bicycle transmission that is currently widely used is a so-called external transmission in which a chain that extends between multiple sprockets is changed via a derailleur.

In addition to this, there is also a so-called internal transmission, which has a transmission mechanism built into the hub of the rear wheel, but it is not widely used.

Further, as a transmission device incorporating a planetary gear mechanism in a crankshaft portion, there is one disclosed, for example, in Japanese Utility Model Publication No. 1982-19.

(Problems to be Solved by the Invention) The present invention relates to a transmission that incorporates a planetary gear mechanism in the crankshaft, similar to the transmission of Utility Model Publication No. 28-19, and solves the problems of the conventional device. The purpose of this invention is to provide an even better transmission.

In other words, the conventional device of Utility Model Publication No. 28-19 had the problem of being difficult to commercialize due to its limited three-speed transmission due to the arrangement of the planetary gears and its complicated structure. Ta.

(Means for Solving the Problems) In order to solve the above-mentioned problems, in the present invention, a plurality of shafts are arranged on the same circumference of a carrier that is integrated with the crank arm, and each of these shafts is provided with teeth. A planetary gear formed integrally with a plurality of rows of gears of different numbers is rotatably fitted, and a sprocket is formed on the outer periphery of an internal gear that meshes with one of the planetary gears to form a driven rotating body. a plurality of sun gears are provided around the crankshaft, the driven rotating body being fitted with the carrier via a one-way clutch, and meshing with each of the planetary gears, respectively;
A serration is formed on the outer periphery of the fixed bearing portion that encloses the crankshaft, and a serration is formed on the inner periphery of a pawl barrel having a plurality of pawls arranged on the outer periphery, and the pawl barrel is fitted into the fixed bearing portion. A one-way clutch is provided between the pawl barrel and each of the sun gears so as to be removably fitted, and one of the one-way clutches can be selectively connected to constitute a bicycle transmission. .

(Function) Since the device of the present invention is constructed as described above, multi-stage shifting of three or more stages is possible, and the entire transmission device can be structurally made thin without any practical problems. Therefore, according to the present invention, it is possible to easily put into practical use a bicycle transmission having three or more gear stages, which does not require changing the chain.

In particular, in the present invention, a serration is formed on the outer periphery of a fixed bearing that encloses the crankshaft, and a serration is formed on the inner periphery of a pawl cylinder having a plurality of pawls arranged on the outer periphery, and this pawl cylinder is fixed. Since it is removably fitted to the bearing, all that is required is to fit most of the assembled transmission into the bicycle frame via the serrations, making it easy to assemble and disassemble during manufacturing or maintenance. Work becomes much easier.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. In the figure, 1 (see Figure 2) is the main pipe of the bicycle frame, 2 is the vertical pipe, 3 is the chain stay,
4 (see Fig. 1) is a hanger pipe; 5 is a fixed bearing portion that is screwed into the hanger pipe 4 and is integrally fixed with the frame; and 6 is a crankshaft rotatably provided through the fixed bearing portion 5; 7 is the ball bearing, 8 is a crank arm fitted onto the crankshaft 6, 9 is a nut, and 10 is a retaining ring for fixing the fixed bearing portion 5 screwed into the hanger pipe 4.

In this embodiment, as shown in FIG. 1, a disc-shaped carrier 11 is attached to the crank arm 8, the center part of which fits into the boss part of the crank arm 8, and the outer peripheral part of which is formed with a protrusion 11a for a gear cover. It is fixed to the flange portion 8a via bolts 12a (see FIG. 2), and a plurality of (four in this embodiment) shafts 13 are connected to the crankshaft 6 on the same circumference of the carrier 11 at equal positions on the circumference. Arrange in parallel. That is, in this embodiment, protrusions 11b (see FIG. 2) are provided at appropriate heights at four locations on the inner surface of the carrier 11, and an annular ring plate 14 is placed on these protrusions 11b. The ring plate 14 is fixed by a bolt 12b (see FIG. 3), and the shaft 13 is provided so as to span between the ring plate 14 and the carrier 11.

Further, a plurality of (three in this embodiment) planetary gears 15a, 15b, 15c each having a different number of teeth are integrally formed, and each of the planetary gears 15 is connected to the shaft 13.
These planetary gears 15a,
An internal gear 16a that meshes with one of the gears 15b and 15c and roller receiving stages 16b and 16c disposed on both sides thereof are integrally formed, and
The driven rotating body 16 is integrally formed by providing a sprocket 16d and a stepped cylindrical portion on its outer periphery.

In this embodiment, in order to facilitate manufacturing, the sprocket 16d is formed separately from the internal gear 16a and the like, and then the two are integrally joined.

Further, a one-way clutch 17 is inserted between an inner stepped portion provided on the inner surface of the outer circumferential portion of the carrier 11 and a stepped cylindrical portion of the driven rotating body 16 facing thereto, so that the driven rotating body 16 is connected to the carrier 11. Rotatably attached in only one direction.

That is, as shown in FIGS. 2 and 4, 17a is a ratchet of the one-way clutch 17 formed on the stepped cylindrical portion of the driven rotor 16, 17b is a pawl pivotally supported on the carrier 11 side, and 17c is this pawl. 17b
This is a spring that biases the latch in the direction of meshing with the ratchet 17a. Of course, this one-way clutch 17 may be of other types.

In addition, in order to support the inside of the driven rotating body 16,
Shafts 13a parallel to the crankshaft 6 are provided across the carrier 11 and the ring plate 14 at multiple locations (four locations in this embodiment) on the same circumference of the carrier 11 and the ring plate 14, and these shafts 13a A small diameter roller 18a and a large diameter roller 18b are rotatably provided in each of the rollers 1 and 1.
8a and 18b are the roller receiving portions 1 of the driven rotating body 16.
6b and 16c respectively, and the driven rotating body 1
6.

In addition, a hollow cylindrical pawl barrel 19 is fitted to the outer periphery of the fixed bearing portion 5 enclosing the crankshaft 6 via an involute serration 20 (see FIG. 5).
A speed change cylinder 21 is fitted onto the outer periphery of this pawl barrel 19, and the planetary gear 1 is fitted onto the outer periphery of this speed change cylinder 21.
The sun gears 22, 23, 24 that mesh with the respective gears 15a, 15b, 15c of 5 are fitted, and the inner peripheral parts of these sun gears 22, 23, 24 and the claw body
A one-way clutch 25,
26 and 27 are provided, and each of these one-way clutches 2
5, 26, and 27 can be selectively connected.

That is, 25a, 26a, 27a (see Figure 6)
are the pawls of each one-way clutch 25, 26, 27, and these pawls 25a, 26a, 27a are a set of two, and have a phase difference of 180° and are undulated in the recessed part provided on the outer periphery of the pawl barrel 19. It is freely supported. Figure 6b
6c shows the one-way clutch 25 for the sun gear 22, FIG. 6c shows the one-way clutch 26 for the sun gear 23, and FIG. 6d shows the one-way clutch 26 for the sun gear 23.
shows a one-way clutch 27 for the sun gear 24. 25b, 26b, 27b are ring-shaped springs that always urge each pawl to rise; 25c, 26c, 27c are sun gears 22, 2;
This is a ratchet formed on the inner periphery of parts 3 and 24.

The claws 25a, 26a, 27a are shown in FIG.
As shown in c and d, they are each pivotally supported on the outer periphery of the pawl barrel 19 with a 60° phase difference. Also 21
a, 21b, and 21c are openings provided in the body of the transmission cylinder 21, where the opening 21a corresponds to the pawl 25a, the opening 21b corresponds to the pawl 26a, and the opening 21c corresponds to the pawl 26a.
corresponds to the claw 27a. As shown in FIG. 7a, these openings 21a, 21b, and 21c are attached to the body of the transmission cylinder 21 at the reference edge of each opening (clockwise edges a, b, and c in FIG. 7a). but
They are arranged with a 60° phase difference, and the lengths of the openings 21a, 21b, 21c are 21a<21
The length increases in order as b<21c. In this example, the opening length is expressed as an angle of 2.
1a is 28°, 21b is 41°, and 21c is 51°.

In addition, 21d in FIG. 7 is a flange provided on one side (crank arm 8 side) of the speed change cylinder 21;
Reference numeral ``e'' indicates an annular groove provided on the opposite side, and 21f indicates notched recesses provided at two locations (180° phase) on the edge of the annular groove 21e.

Further, FIG. 8 shows details of the shift arm 28 which is integrally connected to the shift circumference 21 to perform a shift operation, in which 28a is a ring portion that fits into the body of the shift cylinder 21, and 28b is a ring. These two tongue pieces 28b, which are tongue pieces protruding from the inner side of the portion 28a, are adapted to fit into the notch recesses 21f of the speed change cylinder 21, respectively. 28c is an arm portion projecting sideward from the outer edge of the ring portion 28a;
Reference numeral 8d denotes a wire guide portion that is continuous with the arm portion 28c and protrudes in the shape of a flange. 28e is a spring locking hole provided in the arm portion 28c, and 28f is a wire locking hole also provided in the arm portion 28c.

As shown in FIGS. 1, 3 and 6a, the shift arm 28 is fitted into the body of the speed change cylinder 21 with the tongue piece 28b fitting into the notch recess 21f, and the annular groove 21e. A retaining ring 29 is fitted inside to integrally connect the speed change cylinder 21 and the shift arm 28.

Then, as shown in FIG.
0 end to the hole 28f, the locking fitting 31, and the set screw 3
The bracket 3 is fixed to the shift arm 28 by 2 and protrudes from the hole 28e and the chain stay 3.
A return spring 34 is tensioned between 3 and 3.

Note that 35 shown in FIG. 1 is a washer inserted on the side surface of various rotating members, and 36 is a collar inserted between the carrier 11 and the sun gear 22.

Further, in this embodiment, various dustproof seals made of an elastic material such as soft vinyl chloride resin are provided to close the gaps between the rotating members of the device.

That is, 37 is a ring-shaped seal that is fitted onto the outer circumference of the driven rotor 16 and whose end edge 37a is fitted into the annular source 11c formed on the inner surface of the carrier 11, and 38 is the outer circumference of the ring plate 14. 39 is a ring-shaped seal that closes the gap between the inner periphery of the ring plate 14 and the outer periphery of the ring portion 28a of the shift arm 28; 40 is a fixed bearing portion This is a ring plate-shaped seal that closes between the outer circumferential portion of the shift arm 5 and the inner circumferential portion of the ring portion 28a of the shift arm 28. Note that 41 is a chain that meshes with the sprocket 16d.

Next, the operation of the apparatus of the present invention constructed as described above will be explained. By operating the speed change operation device (not shown) and pulling the operation wire 30 in the direction of arrow A in FIGS. Figure 6b,
When rotated counterclockwise to the maximum at points c and d, the opening 21a provided in the body of the transmission cylinder 21,
21b, 21c, and three sets of six pawls 25a, 26a, 27 provided on the pawl barrel 19 fitted to the fixed bearing portion 5.
The relationship with a is as shown in FIG. 9a. That is, in this case, since the claws 25a, 26a, 27a are all inside the speed change cylinder 21, the ratchets 25c, 26
There is no claw that engages with c and 27c. In this case, therefore, the sun gears 22, 23, 24 can all rotate freely.

In this state, when the crank arm 8 is rotated in the direction of arrow B in FIG. 2 via a crank pedal (not shown), the carrier 11 fixed to the crank arm 8 and the ring integrally connected to the carrier 11 are rotated. Plate 14 rotates in the direction of arrow C in FIGS. Therefore, the one-way clutch 17
Due to the engagement between the pawl 17b and the ratchet 17a, the driven rotating body 16 similarly rotates in the direction of arrow C. Therefore, the driven rotor 16 and sprocket 16d also rotate together with the crank arm 8 in the direction of arrow C, so the chain 41 moves in the direction of arrow D in FIG. 2 to drive the rear wheel (not shown). This makes the bicycle run. In this case, the gear ratio between the crankshaft 6 and the sprocket 16d is 1:1.
It is.

At this time, since the carrier 11 and the driven rotating body 16 rotate integrally, the planetary gear 15 also revolves integrally with the internal gear 16a meshing therewith, so that each gear 15a, 15b of the planetary gear 15 ，
Sun gears 22, 2 meshing with 15c, respectively.
3 and 24 rotate individually depending on their respective tooth ratios, but all of this rotation is caused by the one-way clutches 25 and 24.
Since both 26 and 27 are in the disconnected state, this is allowed without any problem.

In addition, the sun gears 22, 23, 24 are connected to the transmission cylinder 21.
However, in this example, each sun gear is inscribed and meshed with the four planetary gears, so the sun gear needs to be pivotally supported by the central shaft. There isn't.

Next, when the operating wire 30 is loosened one step in the direction of arrow E in FIG. 2 from the state shown in FIG. 9a,
As a result of the shift cylinder 21 rotating clockwise in FIGS. 2 and 9 by the action of the return spring 34, each opening of the shift cylinder 21 changes from the state shown in FIG. 9a to the state shown in FIG. 9b.
Move to the position. As a result, the tips of the pair of claws 27a are exposed in the opening 21c.
A is engaged with a corresponding ratchet 27c by the action of spring 27b as shown in FIG. 6d. The one-way clutch 27 between the sun gear 24 and the fixed bearing 5 is therefore connected.

In this state, move the crank arm 8 to arrow B in Fig. 2.
5, the planetary gear 15 revolves in the direction of arrow F in FIG. 5 via the carrier 11 and shaft 13. However, in this case, since only the sun gear 24 is prevented from rotating in the direction of arrow F by the one-way clutch 27, the planetary gear 15 is rotated through the large diameter gear 15c meshing with the sun gear 24 as shown in FIG. It rotates in the direction of arrow G. Therefore, the internal gear 16a meshing with the medium-diameter gear 15b of the planetary gear 15 rotates at increased speed in the direction shown by arrow H in FIG. 5 due to revolution in the direction of arrow F and rotation in the direction of arrow G. do. This rotation causes the driven rotating body 16 and the sprocket 16d to rotate together, so that the bicycle travels as described above. In this case, the speed increasing ratio of the driven rotating body 16 to the crank arm 8 is approximately 1:1.4 in this embodiment.

In this case, the other sun gears 22 and 23 are also meshed with the gears 15a and 15b of the planetary gear 15, so they rotate, but these sun gears 22 and 23 are connected to the respective one-way clutches 25 and 15, respectively.
26 is in a free state, no trouble will occur.

In this case, the carrier 11 in FIG.
Although the rotation of the driven rotating body 16 in the direction of arrow H is faster than the rotation in the direction of arrow C, this rotational speed difference is tolerated by the one-way clutch 17 (see FIGS. 2 and 4).

Next, when the operating wire 30 is loosened one more step in the direction of the arrow E in FIG. 2 from the state shown in FIG.
Move from the state shown in Figure b to the position shown in Figure c. Therefore, since the second pawl 26a is also exposed from the opening 21b, the one-way clutch 26 by this pawl 26a is also connected.

In this state, move the crank arm 8 to arrow B in Fig. 2.
In this case, the sun gear 23
Since rotation in the direction of the arrow F in FIG. 5 is prevented by the one-way clutch 26, the planetary gear 15 revolves in the direction of the arrow F in FIG. The gear 16a rotates in the direction of arrow H. However, the rotation speed of the planetary gear 15 in the direction of arrow G in this case is faster than the rotation speed in the above case by the difference in the number of teeth, so the speed increase ratio in this case is ultimately larger than the previous speed increase ratio. Become. In this case, the speed increasing ratio in this embodiment is approximately 1:1.6.

In this case, the pawl 27a inside the opening 21c is also in a state of engagement with the ratchet 27c, but in this case no problem occurs because the ratchet 27c of the sun gear 24 rotates in the direction of getting over the pawl 27a.

Next, when the operation wire 30 is loosened one more step from the state shown in FIG. 9c, the opening 21a becomes the state shown in FIG. 9d or FIG. The ratchet 25c of the sun gear 22 is exposed as shown in FIG. 6b.
engage with.

As a result, when the crank arm 8 rotates in the direction of arrow B, in this case, the internal gear 16a rotates in the direction of arrow H due to the revolution of the planetary gear 15 in the direction of arrow F in FIG. 5 and the rotation in the direction of arrow G. Rotate to .
In this case, the rotation speed of the planetary gear 15 in the direction of arrow G is faster than the rotation speed of the planetary gear 15 by the difference in the number of teeth, so the speed increase ratio in this case is ultimately higher than the previous speed increase ratio. becomes even larger. In this case, the speed increasing ratio in this embodiment is approximately 1:
It is 1.9.

When decelerating, contrary to the speed increasing operation described above, pull the operating wire 30 in the direction of arrow A in FIG. 2, and move the speed change cylinder 21 from the state shown in FIG. By changing to states b and a, the gear stage can be shifted from 4 to 3 to 2 to 1.

Openings 21a, 21b, 21c like this embodiment
The speed change action of the speed change cylinder 21 is performed by the three sets of pawls 25a, 26a, 27a protruding outward from the opening one at a time and sequentially meshing with the corresponding ratchets when speeding up, and when decelerating. This is accomplished by pulling three sets of claws protruding outward from the opening into the opening, one set at a time.

In other words, both speed change and deceleration can be achieved by simply moving one set of pawls in and out, and there is no need to synchronize and reverse the operation of the other clutch when operating one clutch as in the past. At times, gear shifts occur smoothly without slipping or simultaneous meshing. Moreover, it has the advantage of being easy to operate and working reliably.

Further, as shown in FIG. 10, the device of the present invention can be used in the above-mentioned gear stages by removing the sun gear 22 and the one-way clutch 25 and fitting a collar 42 in place of the sun gear 22 to the gear shift cylinder 21. 4
The gear shift function is gone, 1:1, 1:1.4,
Can be easily converted into 1:1.6 three-speed transmission.

Furthermore, as shown in FIG. 11, the sun gear 24 and the one-way clutch 27 are also removed and the sun gear 2
If the collar 43 is fitted to the transmission cylinder 21 instead of 4, the shifting function of the second and fourth stages among the aforementioned transmission stages will be eliminated, resulting in a two-stage transmission system of 1:1 and 1:1.6. It can also be made easier.

(Effects of the Invention) As described above, the device of the present invention has only one internal gear 16a inside the driven rotating body 16.
The production of the driven rotary body 16 is facilitated, and the driven rotary body 16 can be reliably supported by the rollers 18a, 18b, etc. Further, the planetary gear 15 includes a plurality of rows of gears 15a, 15b, 15c integrally formed and pivotally supported by the shaft 13.
Since the structure has a plurality of rows of sun gears 22, 23, 24 arranged around the crankshaft 6, which mesh with the gears 15a, 15b, and 15c, the structure is simple because the shaft 13 of the planetary gears 15 is common. Since many shafts 13 (four in this embodiment) can be disposed on the circumference, the load shared by each planetary gear is reduced accordingly, and the entire device can be made thinner, and the chain 41 can be replaced without having to replace it. , an excellent effect can be obtained in that the number of gears can be increased to three or more (four in this embodiment).

Further, in the transmission system of each gear stage of the device of the present invention, the transmission is transmitted from the carrier 11 to the driven rotating body 16 via the one-way clutch 17 in the first stage, and the sun gear 2 in the second stage.
4, the information is transmitted to the driven rotating body 16 via the planetary gear 15c and the internal gear 16a, and the third stage is the sun gear 2.
3, the information is transmitted to the driven rotating body 16 via the planetary gear 15b and the internal gear 16a, and the fourth stage is the sun gear 2.
2. It is transmitted to the driven rotating body 16 via the planetary gear 15a and the internal gear 16a. In other words, in any gear stage, power is transmitted through a linear transmission path orthogonal to the crankshaft 6, and each gear shaft has a dual support structure, so the transmission efficiency of each gear is excellent, and Since it has a reasonable structure in terms of strength, it is easy to manufacture and has excellent durability.

Next, in the present invention, the serrations 20 are formed on the outer periphery of the fixed bearing part 5 that encloses the crankshaft 6, and the serrations 20 are formed on the inner periphery of the pawl body 19, which has a plurality of pawls arranged on the outer periphery. Since this pawl barrel 19 is removably fitted to the fixed bearing portion 5, according to the present invention, the gearbox with most of it assembled is finally attached to the bicycle frame via the serrations 20. Since it only needs to be fitted, assembly and disassembly work is greatly facilitated in terms of manufacturing and maintenance.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the device of the present invention, FIG. 2 is a side view partially shown in - and - cross sections of FIG. 1, and FIG. 3 is a rear view of FIG. 2 partially cut away. 4 is a partial sectional view taken along the - line in FIG. 1, FIG. 5 is a sectional view taken along the - line in FIG. 1, FIG.
sectional view, figure c is - sectional view, figure d is -
7a is a front view of the transmission cylinder, FIG. 7b is a left side view thereof, FIG. 8c is a right side view, FIG. 8a is a front view of the shift arm, and FIG. 9th
Figures a, b, c, and d are explanatory diagrams of the operation of the speed change cylinder and pawl,
FIG. 10 and FIG. 11 are diagrams of modified examples of the device of the present invention. 4... Hanger pipe, 5... Fixed bearing part, 6...
...Crankshaft, 8...Crank arm, 11...
Carrier, 13... Shaft, 14... Ring plate, 15, 15a, 15b, 15c... Planetary gear, 16a... Internal gear, 16d... Sprocket, 16... Driven rotating body, 17... One-way clutch , 18a... Small diameter roller, 18b... Large diameter roller, 19... Claw body, 20... Serration, 21
... Speed change cylinder, 22, 23, 24 ... Sun gear,
25, 26, 27... one-way clutch, 28...
Shift arm, 29... Retaining ring, 30... Operation wire, 34... Return spring, 37, 38, 39, 4
0... Seal, 41... Chien.

Claims (1)

[Claims] 1. A plurality of shafts are arranged on the same circumference of a carrier integrated with the crank arm, and planetary gears each having a plurality of rows of gears each having a different number of teeth are rotatably fitted to each of these shafts, A sprocket is formed on the outer periphery of an internal gear that meshes with one of the planet gears to form a driven rotating body, and this driven rotating body is fitted with the carrier via a one-way clutch, and the driven rotating body is fitted with the carrier through a one-way clutch. A plurality of sun gears are provided around the crankshaft, each meshing with each planetary gear.
A serration is formed on the outer periphery of the fixed bearing portion that encloses the crankshaft, and a serration is formed on the inner periphery of a pawl barrel having a plurality of pawls arranged on the outer periphery, and the pawl barrel is fitted into the fixed bearing portion. A bicycle, characterized in that one-way clutches are provided between the pawl barrel and each of the sun gears so as to be removably fitted, and one of the one-way clutches can be selectively connected. gearbox.