JPH0258150B2 - - 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 problem) In order to solve the above-mentioned problem, in the present invention, three or more shafts are arranged on the same circumference of the carrier integrated with the crank arm, and each of these shafts has a A driven rotating body is formed by integrally forming a plurality of rows of planetary gears with different numbers of teeth rotatably fitted together, and a plurality of rows of internal gears that mesh with each of these planetary gears, respectively, and a sprocket formed on the outer periphery of the driven rotating body. A one-way clutch is provided between the driven rotary body and the carrier so as to be rotatable on the carrier, and a fixed shaft is integral with the frame and the inner peripheral portion of a plurality of rows of sun gears meshing with each of the planetary gears. A one-way clutch is provided between each of the two, and one of these 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.

(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 shaft portion that is screwed into the hanger pipe 4 and is integrally fixed to the frame; and 6 is a crankshaft that is rotatably provided through the fixed shaft portion 5; 7 is its ball bearing, 8 is a crank arm fitted onto the crankshaft 6, 9 is a washer, and 10 is a nut.

In this embodiment, as shown in FIG. The above (five in this embodiment) shafts 12 are arranged at equal positions on the circumference. That is, in this embodiment, the shaft 12 is
is fixed. Note that 14 is a cover plate that is applied to the outer surface of the carrier 11 and fixed with screws 13, and 15 is a washer for the screw 13.

In addition, a plurality of rows (three in this embodiment) of planetary gears 16, 17, and 18 each having a different number of teeth are rotatably fitted to the shaft 12 via a collar 19,
Three rows of internal gears 20, 21, 22 meshing with these planetary gears 16, 17, 18, respectively, are integrally formed, and a driven rotating body 24, which has a sprocket 23 formed on its outer periphery, is mounted on the carrier 11 with a bearing. 25 so as to be rotatable.

Further, as shown in FIG. 1, the carrier 11 is provided with projecting portions 11b at five locations between the arms 11a, and a donut-shaped ring plate 11c is applied to these projecting portions 11b and the end face of the shaft 12. Then, fix it with ten screws 13 as shown in FIG.

Further, a ring plate 24a is similarly fitted on the inner surface side of the driven rotor 24, and there is a line between the inner circumference of the ring plate 24a, which is integral with the driven rotor 24, and the outer circumference of the ring plate 11c, which is integral with the carrier 11. A directional clutch 26 is provided. That is, 26a in FIG. 3 is a ratchet formed on the inner periphery of the ring plate 24a, 26b is a pawl provided on the outer edge of the ring plate 11c so as to be able to engage and detach from this ratchet 26a, and 26c is a pawl that connects this pawl 26b to the ratchet 26a.
This is a spring that urges it into engagement. That is, these ratchets 26a, pawls 26b, and springs 26
A one-way clutch 26 is formed by c.
The one-way clutch may be of other configurations.

Furthermore, three sun gears 27, 28, 29, which mesh with the planetary gears 16, 17, 18, respectively, are loosely fitted to the fixed shaft portion 5 that is integrated with the frame, and the outer peripheral portion of the fixed shaft portion 5 and the sun Gears 27, 28, 2
A one-way clutch 3 is connected between each inner peripheral portion of the
Set 0. That is, in FIG. 4, 30a is a ratchet formed on the inner periphery of each sun gear 27, 28, 29, 30b is three pawls arranged in parallel on the fixed shaft portion 5 so as to be able to engage and detach from these ratchets 30a, and 30c.
are ring-shaped springs that urge these pawls 30b to engage with their respective corresponding ratchets 30a. These ratchets 30a, claws 30
b, a one-way clutch 30 is formed by a spring 30c.

In the present invention, one of the plurality of sets (three sets in this embodiment) of one-way clutches 30 described above can be selectively connected.

Specifically, as shown in this embodiment, a small-diameter cylindrical portion 31a rotatably fits on the outer circumference of the fixed shaft portion 5 having a claw 30b, and a large-diameter cylindrical portion having a larger diameter than the outer diameter of the hanger pipe 4. The wire reel portion 3 is formed integrally with the large diameter cylindrical portion 31b.
1c is provided to form a speed change cylinder 31, and a plurality of stages (three stages in this embodiment) of step portions 32a, 32b, 32c (fifth,
6)) is formed.

As shown in FIG. 1, this speed change cylinder 31 is fitted so that its small diameter cylindrical part 31a surrounds the fixed shaft part 5, and in this fitted state, the opening 3
The three step portions 32a, 32b, 32c of 2 are aligned with the respective circumferential lines of the three claws 30b provided on the fixed shaft portion 5, and each claw 30b is
When the tip of the clutch is located within the opening 32, the pawl 30b projects outward under the action of the spring 30c and engages with the corresponding ratchet 30a, thereby closing the one-way clutch 30.
to connect.

In order to rotate this speed change cylinder 31, an operating wire 33 wound around the wire reel portion 31 is
This is done by operating as shown by arrows A and B in FIG. 33a shown in FIG. 2 is the operating wire 33.
This is a wire end for fixing the wire to the wire reel portion 31c.

Further, 34 shown in FIG.
In the figure, it is a coil spring that is always biased to rotate clockwise, one end 34a of which is locked to the large diameter part 31b of the speed change cylinder 31, and the other end 34b of which is attached to the protrusion of the hanger pipe 4. It is locked to 4a. Note that 35 in the figure is a chain that is wound around the sprocket 23.

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 33 in the direction of arrow A in FIG. When rotated to the maximum in the counterclockwise direction in the figure, the opening 32 provided in the small diameter cylindrical portion 31a of the speed change cylinder 31
The relationship between this and the three claws 30b provided on the fixed shaft portion 5 is as shown in FIG. 7a. That is, in this case, since all the claws 30b are inside the small diameter cylindrical part 31a,
There is no pawl 30b that engages the ratchet 30a. Therefore, in this case the sun gears 27, 28, 2
9 can all rotate freely.

In this state, when the crank arm 8 is rotated in the direction of arrow C in FIG. 2 via a crank pedal (not shown), the carrier 11 fixed to the crank arm 8 and the carrier integrally connected to the carrier No. 11 ring plate 11c rotates in the direction of arrow D in FIG. Accordingly, due to the engagement of the pawl 26b of the one-way clutch 26 with the ratchet 26a, the ring plate 24a integrally connected to the driven rotating body 24 rotates in the direction of arrow e in FIG. 3. Therefore, the driven rotor 24 and the sprocket 23 also rotate integrally with the crank arm 8 in the direction of arrow C in FIG.
The bicycle travels by moving in the direction of arrow F in the figure and driving the rear wheel (not shown). In this case, the gear ratio between the crankshaft 6 and the sprocket 23 is 1:1.

At this time, since the carrier 11 and the driven rotating body 24 rotate integrally, each planetary gear 16, 17,
18 are also meshed with internal gears 20 and 2, respectively.
1 and 22, the sun gears 27, 28, and 29, which mesh with the planetary gears 16, 17, and 18, respectively, also rotate together with the crank arm 8, but this rotation is caused by the one-way clutch. 30 are all disconnected, so there is no problem.

In addition, the sun gears 27, 28, 29 are connected to the transmission cylinder 31.
However, in the present invention, since each sun gear is inscribed and meshed with three or more (in the present invention, five) planetary gears, the sun The gear does not need to be pivoted by a central axis.

Next, when the operating wire 33 is loosened one step in the direction of arrow B in FIG. 2 from the state shown in FIG. 7a,
As a result of the speed change cylinder 31 rotating clockwise in FIG. 2 under the action of the coil spring 34, the opening 32
moves from the state shown in FIG. 7a to the position shown in FIG. 7b. As a result, the tip of one pawl 32b is exposed within the stepped portion 32a of the opening 32, and as a result, this pawl 32b is moved to the corresponding ratchet 3 by the action of the spring 32c.
2a. The one-way clutch 32 between the sun gear 27 and the fixed shaft 5 is therefore connected.

In this state, move the crank arm 8 toward arrow C in Fig. 2.
When rotated in the direction of , the carrier 11, shaft 12,
Each planetary gear 16, 17, 18 via a collar 19
revolves in the direction of arrow G in FIG. However, in this case only the sun gear 27 is connected to the one-way lever 3.
0 prevents rotation in the direction of arrow G, the planetary gear 1 meshing with this sun gear 27
6 rotates in the direction of arrow H in FIG. Therefore, the internal gear 20 that meshes with the planetary gear 16 is indicated by the arrow G.
Due to the revolution in the direction and the rotation in the direction of the arrow H, the rotation speed is increased in the direction shown by the arrow I in FIG. 4. This rotation causes the driven rotary body 24 and the sprocket 23 to rotate together, so that the bicycle travels as described above. In this case, the speed increasing ratio of the driven rotating body 24 to the crank arm 8 is 1 in this embodiment:
It is 1.3.

In this case, the other planetary gears 17 and 18 are also meshing with the internal gears 21 and 22, respectively, so as a result of the revolution and rotation, the sun gears 28 and 29 also rotate to some extent; however, these sun gears 28 and 29 Since each one-way clutch 30 is in a free state, no trouble occurs.

In this case, the rotation of the ring plate 24a in the direction of arrow E is faster than the rotation of ring plate 11c in the direction of arrow D in FIG.
This rotational speed difference is accommodated by the one-way clutch 26.

Next, when the operating wire 33 is loosened one more step in the direction of arrow B in FIG. 2 from the state shown in FIG. 7b, the transmission cylinder 31 further rotates and the opening 32 changes from the state shown in FIG. Move to position c. Therefore, the second claw 30 is also removed from the stepped portion 32b of the opening 32.
Since the claw 30b is exposed, the one-way clutch 30 formed by the pawl 30b is also connected.

In this state, move the crank arm 8 toward arrow C in Fig. 2.
In this case, the planetary gear 17
The internal gear 21 rotates in the direction of arrow I by revolution in the direction of arrow C and rotation in the direction of arrow H in FIG. However, in this case, the rotation speed of the planetary gear 17 in the direction of arrow H is faster than the rotation speed of the planetary gear 16 by the number of teeth.
Eventually, the speed increase ratio in this case becomes larger than the previous speed increase ratio. In this case, the speed increasing ratio in this embodiment is approximately 1:1.5.

In this case, the claw 3 in the stepped portion 32a of the opening 32
2b is also in engagement with the ratchet 30a, but in this case the ratchet 30a of the sun gear 27
Since it rotates in the direction of getting over the claw 30b, no problem occurs.

Next, when the operating wire 33 is loosened one more step from the state shown in FIG. 7c or FIGS. 5a and 5b, the opening 32 becomes the state shown in FIG. A third pawl 30b is also exposed from the stepped portion 32c and engages with the ratchet 30a of the sun gear 29, as shown in FIG. 6b.

As a result, when the crank arm 8 rotates in the direction of arrow C, in this case, the internal gear 22 rotates in the direction of arrow I due to the revolution of the planetary gear 18 in the direction of arrow G in FIG. Rotate to . In this case, the rotation speed of the planetary gear 18 in the direction of arrow H is faster than the rotation speed of the planetary gear 17 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 1.6.

When decelerating, contrary to the speed increasing operation described above, the operating wire 33 is pulled in the direction of the arrow A in FIG. By changing to states b and a, the gear stage can be shifted from 4 to 3 to 2 to 1.

As in this embodiment, the speed change action by the speed change cylinder 31 having a step-like opening 32 is such that, when speeding up, the three pawls 30b protrude outward from the opening 32 one by one and sequentially engage with the corresponding ratchets 30a. During deceleration, the three claws 30b protruding outward from the opening 32 are pulled into the opening 32 one by one.

In other words, both speed change and deceleration can be achieved by simply moving one clutch 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.

(Effects of the Invention) As described above, the device of the present invention has a plurality of rows of internal gears 20, 21, 22 of the driven rotating body 24 arranged in a stepped manner, and a plurality of rows of planetary gears 16, 1 that mesh with the internal gears 20, 21, 22 of the driven rotating body 24.
7 and 18 are pivotally supported by a single shaft 12, and multiple rows of sun gears 27, 28, 29 that mesh with these planetary gears 16, 17, 18 are arranged around the crankshaft 6. From, planetary gear 16,1
Since the shafts 12 of 7 and 18 are common, the structure is simplified, and since many shafts 12 (in this example, 5 shafts) can be arranged on the circumference, the load sharing between each planetary gear is reduced accordingly. As a result, the overall device can be made thinner, and the number of gears can be increased to three or more (four in this embodiment), which is an excellent effect.

In addition, the transmission system of each gear stage is such that the first stage is the carrier 1.
One-way clutch 2 from ring plate 11c of 1
6, the second stage is transmitted to the driven rotary body 24 via the sun gear 27, planet gear 16, and internal gear 20, and the third stage is the sun gear 28, planet gear 17. , is transmitted to the driven rotating body 24 via the internal gear 21, and the fourth stage is the sun gear 2.
9, is transmitted to the driven rotation 24 via the planetary gear 18 and the internal gear 22. 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 Because it has a reasonable structure in terms of strength,
The advantages are that it is easy to manufacture and has excellent durability.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of the device of the present invention, Fig. 2 is a side view thereof, Fig. 3 is a cross-sectional view of Fig. 1, Fig. 4 is a cross-sectional view of the same, and Fig. 5a is a cross-sectional view of the transmission cylinder. FIG. 6A is a plan view showing a partially cutaway state; FIG. FIGS. 7A to 7D are plan views showing the state of the transmission cylinder at each gear stage. 4...Hanger pipe, 5...Fixed shaft part, 6...
Crankshaft, 8...Crank arm, 11...Carrier, 12...Shaft, 14...Cover plate,
16, 17, 18... Planetary gear, 20, 21, 2
2... Internal gear, 23... Sprocket, 24...
...Followed rotating body, 26...One-way clutch, 27,
28, 29... Sun gear, 30... One-way clutch, 31... Speed change cylinder, 32... Opening, 33...
Operation wire, 34...Coil spring, 35...Chain.

Claims (1)

[Claims] 1 Three or more shafts are arranged on the same circumference of a carrier integrated with the crank arm, and multiple rows of planetary gears with different numbers of teeth are rotatably fitted to each of these shafts, and each of these planetary gears and A driven rotary body integrally formed with a plurality of rows of internal gears meshing with each other and having a sprocket formed on its outer periphery is rotatably provided on the carrier, and a one-way clutch is provided between the driven rotary body and the carrier. and one-way clutches are provided between the inner peripheries of the plurality of rows of sun gears meshing with each of the planetary gears and a fixed shaft integral with the frame, and one of these one-way clutches is selected. A bicycle transmission device characterized by being able to be connected to a bicycle.