JPS5828150B2 - Bicycle exterior derailleur - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chain-replaceable bicycle external transmission using a multi-stage sprocket.

The present applicant previously filed Japanese Patent Application No. 50-90492 (Japanese Unexamined Patent Publication No.
2-15033) ≦ However, this transmission has a cam for shifting operation, a reel connected to the operation wire, and a shaft on which the spring is attached, which are fixed separately from the pivot shaft of the parallel link. Because it is mounted on a component, it has a complicated structure and is relatively heavy, and the adjustment bolts and other parts protrude toward the outside of the bicycle, making it dangerous if they come into contact with the human body.

The present invention was made to improve the above-mentioned drawbacks, and the structure is simplified by making the shaft for mounting the speed change operation cam, the reel connected to the operation wire, and the spring also serve as the pivot shaft of the parallel link. In addition to reducing weight,
The conventionally exposed gear shift operation cams, springs, adjustment bolts, movable parts, etc. are covered with covers and outer links provided on fixed members, preventing any protrusions from being exposed on the outside of the bicycle, thereby improving bicycle safety. The purpose is to further increase the

The present invention will be described in detail below with reference to the drawings.

In the figure, 1 is a bicycle frame, 2 is a rear axle, 3 is a multi-stage sprocket rotatably fitted to the shaft 2, 4 is a chain lever, and 5 is a mounting bracket fixed to the shaft 2 with a nut 6.

In the present invention, the plate material is bent into a U-shape so that both side plate parts 7
a, 7b, and a tightening seat 7c at the bent part.
The fixing fitting 7 provided with the bolt 8 is inserted through the tightening seat 7c.
Fix it to the mounting bracket 5 with
, 7b are respectively provided with an inner link connecting shaft hole 7d and an outer link connecting shaft hole 7e, and the boss portion 9a of the inner link 9, the coil spring 10, and the boss portion 11a of the L-shaped bar 11 are connected. , both side plate portions 7a of the fixing member 7.

The inner link connecting shaft 1 is inserted between Ib and passes through the hole 7d.
2, the boss portion 9a of the inner link 9 and the coil spring 10
, and the boss portion 11a of the L-shaped bar 11 are pivotally supported on the fixing member 7.

A bent piece 9b is provided at the upper end of the inner link 9, and an adjustment bolt 13 is screwed into this bent piece 9b.

13a is a lock nut for the adjustment bolt 13.

The lower end of the inner link 9 is shaped like a channel, and a shaft hole 9 for connection with a movable member, which will be described later, is formed in each side plate of the inner link 9.
Provide c.

Further, one end of the L-shaped bar 11 is provided with a bent piece 11b that abuts against the adjustment bolt 13, and the other end is provided with a pin 14.
A cam roller 15 is provided.

The coil spring 10 acts to rotate the inner link 9 clockwise in FIG. 3 and to rotate the L-shaped bar 11 counterclockwise.

Then, a cover 7' is detachably attached to the fixing member 7 so as to cover the outer surface of the fixing member 7.

Also, the outer link 1 forms a parallel link with the inner link 9.
6 is formed into a curved channel shape, and these side plate portions 16
A connecting shaft hole 16c is provided at the upper end of each of a and 16b, and a connecting shaft hole 16d for connecting with a movable member, which will be described later, is provided at the lower end, and the hole 7e of the fixed member 7 and the hole 16c of the outer link 16 are overlapped. and insert the connecting shaft 17,
In that case, a speed change operation cam 18 and a coil spring 19 are fitted to the shaft 17 between the side plate portions 16a and 166 of the outer link 16, and a reel 20 is fitted to the end of the shaft 17 that protrudes outward from the fixed member 7. Insert.

Reference numeral 21 in FIG. 5 is a ring for preventing removal of the reel 20, which is fitted into an annular hole 17a provided at the end of the shaft 17.

As shown in detail in FIG. 6, the speed change operation cam 18 has the same position holding portions a1 and a corresponding to the number of stages of the multi-stage sprocket 3.
'l t a3 t a4 F a5 and the step connecting part b1 that connects each of these same level holding parts. b2. b3. b4゜b
5, and is integrally connected to the reel 20 by a knock pin 22 via the hole 18a.

Then, as shown in FIGS. 3 and 4, one end 19a of the coil spring 19 is engaged with a pin 18b protruding from the cam 18, and the other end 19b of the spring 19 is engaged with the fixing member 7. The cam 18 is urged to rotate in the direction of arrow A.

Note that 16e in FIG. 5 is a fitting groove that serves as a stopper for the knock pin 22.

Further, as shown in FIGS. 1 and 4, the wire adjuster 23 of the speed change operation wire (not shown) is fixed to the fixing member 7, and the inner wire (not shown) is wound around the reel 20. , its end portion is fixed by a wire set screw 24 provided in the hole 20a of the reel 20.

Further, as shown in FIGS. 3, 4, 7, and 8, the upper end of a box-shaped movable member 25 enclosed by the outer link 16 is connected to the lower end of the inner link 9 by a shaft 26. 9c, and the movable member 25
The lower end of the outer link 16 is connected to the hole 1 by the shaft 27.
6d, a coil spring 28 is fitted to the shaft 26, and the movable member 25 is always rotated clockwise relative to the inner link 9 by acting as shown by arrow B in FIG. to energize it.

Further, as shown in FIGS. 1 and 2, a shaft is installed in the middle of a recombinant frame 33, which pivotally supports the guide wheel 29 of the chino 4 by a shaft 30, and supports the tension ring 31 by a shaft 32. 3
A coil spring 35 is fitted to the shaft 34, and the end of this shaft 34 is connected to the third
As shown in the figure, it is rotatably fitted to the vertical wall portion 25a of the movable member 25.

Reference numeral 36 indicates a link for preventing removal provided at the protruding end of the shaft 34;
3' is an opposing plate of the recombinant frame 33; 37 is a stopper pin protruding from the recombinant frame 33; 35a is an extended end of the coil spring 35; by locking this to the stopper pin 37, the recombinant frame 33 is urged to rotate in the direction of arrow C about shaft 34 in FIG.

Next, the operation of the apparatus of the present invention constructed as described above will be explained.

Now, if the movable member 12 is at a high speed position as shown in FIG. ), the inner wire rotates the cam 18 via the reel 20 as shown by the arrow in FIG.

Then, the lever 11 that is in contact with the cam 18 rotates in the direction of arrow E.

The lever 11 can rotate in the direction of arrow E against the inner link 9 against the spring 10, but the spring 10 is set in advance with a force greater than the force required to reassemble the chino 4, so it will not bend. .

That is, the lever 11 and the inner link 9 can rotate together from the state shown in FIG. 3 to the state shown in FIG. 7.

In this case, the spring 28 is deflected and the outer link 16 also rotates together with the inner link 9 as shown in FIG.
5 moves to the low-speed side, and the cheno 4 is replaced with the sprocket 3 on the low-speed side by the step difference due to the rotation of the cam 18.

FIG. 7 shows a state in which the chino 4 is replaced with the sprocket 3 of the lowest speed stage.

Also, the movable member 25 is in the low speed transmission position (see Figure 7).
If the recombinant frame 33 is movable when the crank is rotated, when the transmission wire is loosened by the operation tool, the reel 20 is rotated by the coil spring 19 and winds up the inner wire.

At the same time, the cam 18 also rotates in the direction of arrow A in FIG.

When the cam 18 rotates in the direction of the arrow A in this way, the movable member 25 becomes movable, so the inner link 9 tries to rotate toward the high speed side due to the force of the spring 28, and the lever 11 also rotates in the direction of the arrow A due to the force of the spring 10. It tries to rotate in the direction of F.

Therefore, when the cam 18 rotates in the direction of the arrow A, the lever 11 rotates in the direction of the arrow F by the amount of the step caused by the rotation of the cam 18, and the inner and outer links 9 and 16 simultaneously change from the state shown in FIG. 7 to the state shown in FIG. As a result, the movable member 2
5 moves to the high speed side, and the cheno 4 is replaced with the sprocket 3 on the high speed side by the amount of the step of the cam 18.

Next, when the crank is stopped, the movable member 25 cannot be moved because the cheno 4 cannot be replaced.

However, now that the movable member 25 is in the high-speed transmission position as shown in FIG. rotates in the direction of the arrow in FIG.

In this case, since the movable member 25 cannot be moved, the inner and outer links 9 and 16 cannot naturally rotate.

However, since the lever 11 can rotate in the direction of arrow E with respect to the inner link 9 against the spring 10, the lever 11 can rotate against the cam 1.
As the cam 8 rotates, the cam 18 rides on the stepped cam 18.

Therefore, the stopper bent piece 11b protruding from the lever 11 is separated from the adjustment bolt 13, as shown in FIG.

That is, the force that causes the links 9 and 16 to rotate toward the lower speed side is stored in the coil spring 10.

When the crank rotates in this state and the movable member 25 becomes movable, the force stored in the spring 10 acts over the spring 28, and as a result, the link 9.degree. Rotate until it hits the adjustment bolt 13 as shown in FIG.

In other words, the movable member 25 moves to the low speed side, and the chino 4 is changed to a stage on the low speed side by the difference in stage of the cam 18.

Further, when the movable member 25 is in the low-speed transmission position as shown in FIG. 7, and the crank is stopped and the movable member 25 cannot be moved, when the transmission wire is loosened by the operating tool, the coil spring 19 By the force of, reel 20
The inner wire is wound up, and at the same time the cam 18 rotates in the direction of arrow A.

However, since the movable member 25 cannot be moved, the links 9, 16 and the lever 11 cannot rotate together.

However, since the cam 18 rotates in the direction of arrow A as shown in FIG. 9 from the state shown in FIG.
5 and the cam 18, a gap corresponding to the step due to the rotation of the cam is created as shown in FIG. 9.

In this state, when the crank rotates and the movable member 25 becomes movable, the force of the spring 28, which always tries to rotate the links 9 and 16 toward the high speed side, causes the links 9 and 16 and the lever 11 to be moved by the roller at the tip of the lever. 15 rotates until it hits the step of the cam 18, the movable member 25 moves to the high speed side as shown in FIG. will be carried out.

Next, the effects of the device of the present invention will be explained.

In conventional transmissions of this type, the cam for speed change operation, the reel that connects to the operating wire, and the shaft to which the spring is attached were installed on a fixed member separate from the parallel link pivot shaft, resulting in a complex structure. In addition to being relatively heavy, the adjustment bolts and other components protrude outward from the bicycle, making them dangerous if they come into contact with the human body.

In contrast, in the present invention, the cam 18 for speed change operation, the reel 20 connected to the operation wire, and the spring 19
Since the shaft 17 on which the parallel link 16 is attached is also used as the pivot shaft of the parallel link 16, the structure can be simplified and the weight can be reduced.

In addition, the device of the present invention has a conventionally exposed gear shift operation cam 18.
．． Spring 19. Adjustment bolt 13, movable member 25, etc.
Since the fixing member 7 is covered with the cover 7' and the outer link 16 to prevent the protrusions from being exposed to the outside of the bicycle, the safety of the bicycle is further increased, and
This has the excellent effect of making the external transmission of a bicycle more compact and improving its appearance.

[Brief explanation of the drawing]

Fig. 1 is a side view showing how the exterior transmission of the present invention is installed, Fig. 2 is a front view of the same as seen from the front, and Fig. 3 is the second
FIG. 4 is a side view of FIG. 3 showing the internal structure, FIG. 5 is an exploded perspective view of the main parts of the device of the present invention, and FIG. 6 is a gear shift operation. Detailed views of the cam and FIGS. 7 to 9 are explanatory views of the operation of the device of the present invention corresponding to FIG. 3. 1... Bicycle frame, 2... Rear axle, 3...
Multi-stage sprocket, 4...Che 7.5...Mounting bracket A
, 7-...Fixing bracket, 7'...Cover, 9...Inner link, 10...Coil spring, 11...L-shaped bar 12...Connection shaft, 13...Adjustment bolt , 15...
・Cam roller, 16...Outside link, 18...Cam for speed change operation, 19...Coil spring, 20...Reel, 22...Dowel pin, 23...Wire adjuster 24...Wire stopper Screw, 25... Movable member, 26.27... Connection shaft, 28... Coil spring,
29... Guide wheel, 31... Tension shaft, 33... Recombinant frame, 34... Shaft, 35... Coil spring.

Claims (1)

[Claims] 1 A parallel link 9 is attached to the fixed member 7 fixed to the frame 1.
A replacement frame 33 that supports the guide wheel 29 and the tension shaft 31 is rotatably attached to the movable member 25 connected via the movable member 16, and a gear shift operation cam 18 is attached to the connecting shaft 17 between the fixed member 7 and the outer link 16. , a spring 19 is provided that biases the cam 18 so as to always rotate in one direction, and a spring 19 is provided to cover the outside of the shift operation cam 18, the spring 19 that rotates the cam 18, and the movable member 25. The outer link 16 is formed in a curved channel shape, and an L-shaped bar 11 is pivotally supported on the connecting shaft 12 between the fixing member 7 and the inner link 9.
One end of the lever 11 is connected to the speed change operation cam 18 by a spring 10, and the other end 11b of the lever 11 is detachably engaged with the inner link 9, and these L-shaped bars 11 and springs 10 The upper part of the inner link 9 is housed in the fixing member 7 formed by bending a plate material into a U-shape, and a cover 7' that covers the outside of the upper end portions of the inner link 9 and the outer link 16 is placed on the outside of the fixing member 7. and the fixing member 7
A bicycle external transmission device 1 is provided with a reel 20 that rotates together with a speed change operation cam 18 on the connecting shaft 17 that protrudes further, and an inner wire of an operation wire is connected to this reel 20.