JPH0226796Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to a bicycle gear shift operation lever device, and more specifically, to one that reduces rotational resistance in the direction of pulling the operation cable and improves operability. .

[Conventional technology]

The gear shift operation lever for operating a bicycle transmission has a disc-shaped base that wraps the end of the operation cable around its outer periphery and holds it, and an operation arm on which the rider hangs his/her finger. It is rotatably supported with a certain amount of frictional resistance on a lever shaft attached to the lever shaft. When this operating lever is rotated in one direction, the operating cable is wound around the disc-shaped base and pulled, while when it is rotated in the opposite direction, the cable is unwound around the disc-shaped base. , which imparts axial movement to the operating cable.

By the way, the reason why a certain amount of frictional resistance is applied to the rotation of the operating lever as described above is because the operating cable is constantly pulled elastically toward the transmission by a spring built into the transmission. This is to overcome the elasticity of this spring and hold the operating lever at a desired rotational position. If this frictional resistance is smaller than a predetermined value, the operating lever will rotate back due to the pulling force applied to the cable by the transmission.

As a result of the frictional force applied to the rotation of the operating lever itself, the operating force required to rotate the operating lever in the direction of pulling the cable and the operating force required to rotate the operating lever in the direction of letting out the cable are There is a big difference in the operating force required. In other words, when rotating the cable in the direction in which it is fed out, a relatively small force is required, which is the resistance force applied to the operating lever minus the pulling force applied to the cable by the spring. , when rotating in the direction of pulling the cable, the operating force must be sufficient to overcome the combined resistance force applied to the operating lever and the pulling force applied to the cable. do. Therefore, it is difficult to perform delicate operations when operating the transmission in the direction of pulling the operating cable.

For example, Japanese Utility Model Publication No. 51-25087 discloses a lever that has been improved to solve the above-mentioned problems of the conventional general operation lever and reduce the resistance when rotating in the direction of pulling the cable. The structure shown has already been proposed. This device is constructed by fitting the base of the lever into a roller that is rotatably fitted around the lever shaft with a certain amount of frictional resistance through a one-way transmission clutch consisting of a ratchet mechanism. . In this way,
Since the lever does not rotate back relative to the roller, it is essentially held in a predetermined rotational position by the frictional force exerted on the roller, whereas when rotating in the direction of pulling the cable, , it can rotate regardless of the frictional resistance of the rollers. Therefore, the operating force required to rotate the cable in the direction of traction is sufficient to overcome the elastic pulling force applied to the cable by the spring on the transmission side. become.

[Problem that the invention attempts to solve]

However, in the structure in which the ratchet mechanism is interposed between the roller and the operating lever, which have frictional resistance to their rotation as described above, the resistance force applied to the roller is substantially caused by the small ratchet pawl and ratchet tooth. Since the information is transmitted to the operating lever only through engagement, it is necessary to make this ratchet pawl relatively large and to maintain the strength of the ratchet mechanism above a certain level by making the ratchet pawl that engages it relatively large and having a relatively large spacing between the teeth. It was hot. Therefore, the operating lever cannot be held in a stepless rotating position, and noise is generated only when rotating in the direction of pulling the operating cable.

This invention was devised under the above circumstances, and instead of the above-mentioned ratchet mechanism, it is simpler and more advantageous in terms of strength, and the operating lever can be rotated through nearly stepless rotation angles. This bicycle gear shift lever device uses a one-way clutch that can be held in place and does not generate noise, making it easier to rotate the cable in the direction of pulling the cable than with conventional levers. The task is to provide the following.

[Means to solve the problem]

In order to solve the above conventional problems, the present invention takes the following technical measures.

That is, the present invention includes a roller that is rotatably supported with a predetermined frictional resistance against the lever shaft, and a roller that is rotatably supported with respect to the lever shaft while being held within the boss portion. In the bicycle speed change operation lever device comprising an operation lever, the outer peripheral surface of the roller is formed with fine irregularities, and the inner wall of the boss portion is provided with a sliding surface extending linearly in a direction inclined with respect to the radius of the roller. A holding space is formed with a moving wall, and within this holding space, a first surface that corresponds to the sliding wall and makes surface sliding contact therewith, and a substantially cylindrical inner surface that corresponds to the peripheral surface of the roller. and a second surface formed with fine irregularities that can engage with the irregularities on the outer peripheral surface of the roller, while biasing the stopper member toward the peripheral surface of the roller by a spring. It is characterized by the fact that it has been incorporated.

[Effect]

The sliding wall that extends linearly in a direction oblique to the radius of the roller is arranged so as to gradually move away from the outer peripheral surface of the roller located in the vicinity of the sliding wall.
This sliding wall and the peripheral surface of the roller facing it cooperate to form a wedge-shaped space. The stopper member incorporated in the holding space has a first surface in sliding contact with the sliding wall, and a second surface in contact with the outer circumferential surface of the roller. However, since the second surface has fine irregularities that correspond to the irregularities formed on the outer circumferential surface of the roller, when these two irregularities engage with each other, there is a gap between the second surface and the outer circumferential surface of the roller. There is no slippage.

Here, when an attempt is made to rotate the lever in one direction, the stopper member biased by the spring causes the circumferential surface of the roller to move, causing the above-mentioned sliding wall and the circumferential surface of the roller to form. It digs into the bottom of the wedge-shaped space. This biting phenomenon is caused by the lack of slippage between the outer circumferential surface of the roller and the second surface of the stopper member as described above.
It will definitely happen. This biting of the stopper member locks the lever against the roller, and the lever is held at a predetermined rotational position by the frictional resistance previously applied to the roller.

On the other hand, when an attempt is made to rotate the lever in the opposite direction, the outer peripheral surface of the roller moves in a direction to remove the stopper member from the wedge-shaped space, so it is unlikely that the stopper member will bite into the wedge-shaped space. Therefore, the lever has almost no resistance against the roller. It should be noted that the bite release action of the stopper member is also reliably performed because the unevenness on the second surface of the stopper member and the unevenness on the outer circumferential surface of the roller are engaged with each other. At this time, the force required to rotate the lever is sufficient to overcome the pulling force applied by the cable.

[Effect of idea]

From the above, according to the bicycle gear shift operation lever device of the present invention, basically, when rotating in the direction of pulling the cable, only the force needed to overcome the pulling force applied to the cable is sufficient. This solves the problem of conventional levers requiring a large amount of force to pull the cable.

Moreover, in the present invention, the stopper member acts as a wedge for locking the roller and the lever due to the difference in the direction of relative rotation of the roller forming one wall of the wedge-shaped space with respect to the boss portion of the lever. By releasing the wedge action, a one-way clutch is essentially formed between the roller and the lever, so the lever can be held almost steplessly against the roller, and there is no noise at all. Does not occur.

Furthermore, the above-mentioned locking and unlocking actions of the stopper member are reliably performed by providing fine irregularities that can engage with each other on the second surface of the stopper member and the outer peripheral surface of the roller that contacts this. Therefore, the uncertainties in function and operation that occur when a simple wedge-shaped member is used as a stopper member are completely eliminated.

[Explanation of Examples]

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.

A lever shaft 2 is directly attached and fixed to the side of the upper pipe 1 of the bicycle frame. This lever shaft is
A square base seat 3 is provided, and its cylindrical inner surface is applied to the outer surface of the frame 1 and brazed. This lever shaft 2 further has a distal end 4a of a cylindrical shaft portion 4 shaped differently to have an oval cross section, and a screw hole 5 is bored in the axial direction from the end surface. The lever shaft 2 is fitted with a detent fitting 7 which cannot be rotated by fitting the square hole 6 into the square seat 3, and then the lever is inserted into the cylindrical base 4 via a bush 8. A disc-shaped base 10 of 9 is rotatably fitted.

The lever 9 has a disc-shaped base 10 to be supported pivotally.
and an operation arm part 11 on which a rider hangs his or her fingers, and the outer periphery of the disc-shaped base 10 has a reel-shaped concave groove 12 for winding the operation cable W or a nipple holding hole 13 continuous therewith. A shaft support hole 14 that can fit into the outer periphery of the bush 8 or a boss formed in a diameter larger than the shaft support hole 14 so as to be continuous with the outer part of the shaft support hole 14 is provided inside. Section 15 is opened. However, the shaft support hole 14
The actual length of the bushing 8 is slightly shorter than that of the bush 8.

In an annular space surrounded by the shaft portion 4 of the lever shaft 2 protruding into the boss portion 15 and the inner wall 15a of the boss portion 15, a roller 16 substantially rotatably supported by the shaft portion 4 of the lever shaft 2 is provided. is rotatably supported.
This roller 16 is given a certain amount of frictional resistance to the lever shaft 2, and this is done by fitting the oval hole 17 into the oval-shaped cross section of the end 4a of the lever shaft. This is achieved by pressing the friction plate 18, which cannot rotate relative to the roller 16, against the outer surface of the roller 16.

That is, it is applied to the outside of the friction plate 18,
In addition, a bolt 20 is screwed into the screw hole 5 of the lever shaft 2 to hold down the presser metal fitting 19, in which the locking piece 19a is engaged with the engaging groove 7b formed at the tip of the arm portion 7a of the detent fitting 7. Therefore, the inner surface of the friction plate 18 is pressed against the outer surface of the roller 16. As mentioned above, the locking piece 19a of the presser metal fitting 19 is locked by the locking metal fitting 7, making it impossible to rotate, so the bolt 20 screwed from the outer surface thereof
Looseness is minimized. As described above, as a result of the substantial length of the bush 8 disposed within the shaft support hole 14 of the disc-shaped base 10 being longer than the substantial length of the shaft support hole 14, the length of this bush 8 is longer as shown in FIG. The tip slightly protrudes from the bottom surface of the boss portion 15, and the roller 16 and the inner surface 15a of the boss portion are not in direct contact. Therefore, the boss portion 15 of the lever
is not directly regulated by the frictional resistance applied to the roller 16.

As shown in detail in FIG. 4, on the outer circumferential surface of the roller 16, fine irregularities 28 consisting of, for example, knurling are continuously formed over the entire circumference.

In this example, as clearly shown in FIG. 2, on the inner wall 15a of the boss portion 15 of the lever,
An angular cylindrical holding space 22 is formed with a sliding wall 21 extending substantially tangentially to the outer circumference of the roller 16 and linearly in the direction of the operating arm 11 of the lever. The tip of this holding space 22 has a wedge shape with a pointed tip due to the outer circumferential surface 16a of the roller 16 and the sliding wall 21 extending substantially tangentially to the outer circumferential surface 16a. Inside this holding space 22, there is provided a stopper having a rectangular shaft shape as a whole and having a first surface 23 having a planar shape that is in contact with the sliding wall 21, and a second surface 24 having a cylindrical inner surface that corresponds to the outer periphery of the roller. A member 25 is incorporated so as to be movable in the tangential direction, and is elastically biased toward the circumferential surface of the roller by a compression coil spring 26. As clearly shown in FIG. 1, the holding space 22 is located at the disc-shaped base 10 of the lever.
It is formed by hollowing out a predetermined portion of the side surface of the portion that continues from the operating arm portion 11 into a square groove shape. The second surface 24 of the stopper member 25
As shown in detail in FIG. 4, there are formed fine asperities 29 that can engage with fine asperities (knurlings) formed on the outer circumferential surface of the roller. Thereby, when the outer peripheral surface of the roller and the second surface 24 of the stopper member 25 are brought into contact with each other, they do not slide against each other.

Next, the operation of the bicycle shift operation lever device of this example will be explained based on FIGS. 2 and 4.

The cable W is connected by a spring on the transmission side.
The lever 9 is always biased in the direction of the arrow q, and thereby the lever 9 is given a rotational force in the direction of the arrow Q. When this lever 9 is rotated in the direction of the arrow P, the cable W is pulled in the direction of the arrow P, and conversely, the cable W is pulled in the direction of the arrow P.
When the cable W is rotated back in the direction, the cable W is let out in the direction of the arrow q.

Normally, when the cable W is pulled in the direction of the arrow q and the lever 9 attempts to rotate in the direction of the arrow Q, the stopper member 25 in the holding space 22
is pushed by the spring 26, and is caused by the roller 16 tending to rotate relatively counterclockwise due to the engagement of the irregularities on the outer periphery with the irregularities on the second surface 24. The roller 16 is moved forward and wedged between the sliding wall 21 and the outer circumferential surface 16a of the roller 16.

The lever 9 and the roller 16 are thus locked together, and the lever 9 is held in the desired rotational position by the frictional force applied to the roller 16. If the lever 9 is actively rotated in the direction of the arrow Q from this point on, the lever 9 and the roller 16 will rotate together. The force required to rotate the lever 9 at this time is the force obtained by subtracting the pulling force of the cable W in the direction of arrow q from the rotational frictional force applied to the roller 16.

On the other hand, when trying to rotate the lever 9 in the direction of arrow P, the outer circumferential surface 1 of the roller 1 out of the sliding wall 21 forming a wedge-shaped space and the outer circumferential surface 16a of the roller
6a rotates clockwise relative to the sliding wall, the stopper member 25 is dragged by the movement of the roller and is slightly retracted in the direction of compressing the spring 26, releasing the lock. Ru. As a result, there is no resistance to the rotation of the lever 9 in the counterclockwise direction in FIG. By rotating the cable in the direction of arrow P, the cable W can be pulled.

Of course, the scope of the present invention is not limited to the above-described embodiments. For example, in the embodiment, the lever shaft 2
is directly attached to the frame, but this lever shaft 2
can also be attached to the frame via a clamp band. In addition, lever shaft 2 and bush 8
Although these are formed separately, a portion corresponding to the bush may be formed integrally with the lever shaft 2.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of the components of an example of the bicycle shift operating lever device of the present invention, and Fig. 2 is a state in which the boss portion or holding space of the disc-shaped base of the lever is exposed to the outside. 3 is a sectional view taken along the - line in FIG. 2, and FIG. 4 is an enlarged detailed view of the contact portion between the stopper member and the roller. 2...Lever shaft, 9...Operation lever, 15...
Boss portion, 16...Roller, 21...Sliding wall, 22
...Holding space, 25... Stopper member, 26...
Spring.

Claims (1)

[Claims for Utility Model Registration] A roller rotatably supported with a predetermined frictional resistance against the lever shaft, and the roller supported rotatably around the lever shaft while being held within the boss portion. In the bicycle shift operation lever device, the outer circumferential surface of the roller is formed with fine irregularities, while the inner wall of the boss portion is formed with a straight line in a direction inclined with respect to the radius of the roller. A holding space is formed with an extending sliding wall, and within this holding space, a first surface that corresponds to the sliding wall and is in surface sliding contact therewith, and a substantially cylindrical surface that corresponds to the peripheral surface of the roller. A substantially wedge-shaped stopper member having an inner surface and a second surface formed with fine irregularities capable of engaging with irregularities on the outer peripheral surface of the roller is urged toward the peripheral surface of the roller by a spring. A bicycle gear shift operation lever device that is characterized by incorporating