JPH0133437Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a bicycle derailleur, more specifically, a base member, a pair of link members pivotally supported to the base member via a pair of connection shafts, and a pair of connection shafts attached to these link members. A derailleur comprising a link mechanism consisting of four members and a movable member having a chain guide pivotally supported through the link mechanism, the link mechanism being deformed by operation of an operating wire, and the movable member being moved relative to the base member. Regarding.

Generally, in this type of derailleur, one of the four members constituting the link mechanism is provided with a fixing device for the operating wire, and one of the four connecting shafts is connected to the connecting shaft. The two members of the link mechanism connected by a shaft are rotatably supported, and an outer receiver of an outer tube for guiding the wire is supported at one end of the connecting shaft, and the outer receiver is used to support the outer receiver when the link mechanism is deformed. The connecting shaft is freely rotated to reduce the degree of bending of the wire with respect to the outer receiving axis.

However, in the case of this conventional structure, it is necessary to provide each of the two members of the link mechanism connected by the outer receiving support connecting shaft with a shaft hole large enough to allow the connecting shaft to be inserted loosely. A gap is formed between the inner circumferential surface of each shaft hole provided in the two members and the outer circumferential surface of the connecting shaft, and these gaps cause play in the link mechanism, and as a result, the operating stroke of the wire is reduced by an amount equivalent to the play. Not only did this have the disadvantage of having to make it extra long, but it also made it impossible to accurately align the operating lever to a specific position. In addition, in the case of this conventional structure, when the link mechanism is deformed, a shearing load acts on the connecting shaft for supporting the outer receiver, and the rotational resistance of the connecting shaft and eventually the outer receiver becomes large.As a result, when the link mechanism is deformed, The outer receiver does not rotate by an appropriate amount of rotation, and the degree of bending of the wire with respect to the outer receiver axis increases, which not only makes the pulling operation of the operating wire difficult, but also makes the wire easy to break, and the chain guide tool The movement position of the object becomes incorrect.

The present invention has been devised in view of the above points, and the purpose is to use a cylindrical body, loosely fit this cylindrical body around the outer circumference of at least one of the four connecting shafts, and connect the cylinder with the said connecting shaft. By being fixed to one of the two members in the link mechanism and relatively rotatably fitted to the other, the at least one connecting shaft can be freely rotated, and it is possible to eliminate rattling of the link mechanism. Moreover, it is possible to prevent a shearing load from acting on the at least one connecting shaft when the link mechanism is deformed.

Therefore, the configuration of the present invention includes a base member, a pair of link members that are pivotally supported on the base member via a pair of connecting shafts, and a chain guide that is pivotally supported on these link members via a pair of connecting shafts. A derailleur is provided with a link mechanism consisting of four members with a movable member having a tool, and the link mechanism is deformed by operation of an operating wire to move the movable member relative to the base member, At least one of the connecting shafts is rotatable relative to the two members of the link mechanism connected by the connecting shaft, and a wire fixture for fixing the wire and the wire are attached to one end of the connecting shaft. A cylindrical body is loosely fitted around the outer periphery of the connecting shaft which supports one of the outer cylinders to be guided and the outer holder and is free to rotate, the cylindrical body is fixed to one of the two members, and the other is fixed to one of the two members. By being fitted in a relatively rotatable manner, one or both of the wire fixing tool and the outer receiver can be freely rotated, and the link mechanism can be prevented from rattling, and When the link mechanism is deformed, no shearing load is applied to the connecting shaft, which is free to rotate with respect to the members of the link mechanism.

Next, one embodiment of the derailleur of the present invention will be described based on the drawings.

What is shown in the drawing is a rear derailleur, and its basic structure is, as shown in FIGS. 1 and 2, a base member 1, a pair of first and second connecting shafts 5, A pair of first and second link members 2, 6 and these link members 2, 3 pivotally supported via 6
The link mechanism A is comprised of four members, including a movable member 4 having a chain guide 9 which is pivotally supported via a pair of third and fourth connecting shafts 7 and 8.

The base member 1 is fixed via a horizontal shaft 11 to a bracket 10 fixed to a backhawk of a bicycle frame, and a pair of mounting pieces are provided facing each other on one side of the base member 1. The link members 2 and 3 are pivotally supported via the first and second connection shafts 6 and 7, and the third and fourth connection shafts 7,
The movable member 4 is pivotally supported via the movable member 8.

This movable member 4 has a similar shape to the base member 1, and has mounting pieces facing each other on one side thereof, and the third and fourth connecting shafts 7 described above on this mounting piece.
8 is attached to the link members 2 and 3 so as to be pivotable relative to each other, and on the other side is the chain guide tool 9 having a pulley via a horizontal shaft 12 extending in the same direction as the horizontal shaft 11. is installed so that it can rotate only within a certain range.

Further, in the derailleur configured as described above, a return spring (not shown) is provided between either one of the link members 2 and 3 and the movable member 4 or the base member 1, so that the chain guide 9
is applied in the axial direction of a multi-stage sprocket device (not shown), that is, to the top side or low side, usually to the top side, and one member in the link mechanism A (link member 2 in the drawings) is A wire fixing device 13 for the operation wire W is provided, and by pulling the wire W, the link mechanism is deformed against the return spring, and the movable member 4 is moved forward. When operated, the link mechanism is deformed by the restoring force of the return spring, and the movable member 4 is moved back, and the reciprocating movement of the movable member 4 moves the drive chain, which is hung on the pulley of the chain guide 9, to the above-mentioned position. It replaces one sprocket of a multi-stage sprocket device.

According to this invention, in the derailleur configured as described above, among the first to fourth connecting shafts 5, 6,
For example, the second connecting shaft 6 is free to rotate with respect to the base member 1 and the second link member 3 connected by the second connecting shaft 6, and an outer wire that guides the wire W is attached to one end of the second connecting shaft 6. While supporting the outer receiver 14 of the cylinder O, a cylinder 15 is loosely fitted around the outer circumference of the second connecting shaft 6, and both ends of the cylinder 15 are
It is fixed by being non-rotatably fitted into one of the pair of shaft holes 1a, 1b and shaft holes 6a, 3b provided in the base member 1 and the second link member 3.

In the above configuration, the inner diameter of the cylindrical body 15 is slightly larger than the outer diameter of the second connecting shaft 6, so that the second connecting shaft 6 can freely rotate with respect to the cylindrical body 15, and This cylindrical body 15 is provided with a cut groove 15a over its entire length.
a allows the diameter of the cylindrical body 15 to be slightly reduced, and the elastic restoring force due to this diameter reduction causes the second link member 3 to
The shaft holes 3a and 3b are fitted and fixed. Both ends of this cylinder 15 are made to protrude outward from the second link member 6, and the protrusions are fitted into the shaft holes 1a, 1b of the base member 1 so as to be relatively rotatable. The cylindrical body 15 is fitted and fixed into the shaft holes 1a and 1b of the base member 1, and the second link member 6
It is also possible to allow relative rotation with respect to the shaft holes 3a, 3b. Further, the number of the cylinders 15 may be one for one connecting shaft as shown in the figure, or two may be provided for each connection shaft.
In this case, one cylinder is fitted into the shaft holes 1a, 3a, and the other cylinder is fitted into the shaft holes 1b, 3b. Moreover, it is not necessary to provide the cut groove 15a in the cylinder 15. Further, the cylindrical body 15 is mainly made of spring steel and hardened, or made of stainless steel, but the material thereof is not particularly limited.

The second connecting shaft 6 has a radial threaded hole 6a at one end, supports the outer receiver 14 in the threaded hole 6a, and deforms the other end plastically to prevent it from falling off from the cylindrical body 15. It prevents.

The outer receiver 14 includes a cylindrical shaft portion 14a having an insertion hole for the wire W at the center and a threaded outer periphery, and a bowl-shaped receiving portion 14b provided at one end of the cylindrical shaft portion 14a. The cylinder shaft part 14a is screwed into the screw hole 6a of the second connecting shaft 6, one end of the outer cylinder O is supported by the bowl-shaped receiving part 14b, and the cylinder is inserted into the outer cylinder O and the outer receiver 14. One end of the wire W is made to protrude outward from the outlet of the outer receiver 14 to connect the fixing tool 13.
It is fixed at

The present invention is constructed as described above.
In the state shown in the figure, the chain guide 9 is in the so-called top position corresponding to the smallest diameter high-speed sprocket in the multi-stage sprocket device, and when the operating wire W is pulled from this top position, the outer Fixture 1 from the outlet of receiver 14
3 becomes substantially shorter, the first and second link members 2 and 3 are forcibly swung around the first connecting shaft 5 and the cylindrical body 15, and this oscillation Due to this movement, the movable member 4 moves forward toward the low side (in the direction of arrow X in FIG. 2). Then, the fixture 13 moves forward in the direction of the arrow X following this movable member 4, and the outer receiver 14 supported on the second connecting shaft 6
rotates in the direction shown in Figure 2.

This rotation of the outer receiver 14 can prevent the degree of bending of the operating wire W with respect to the outer receiver axis from increasing. Further, a cylindrical body 15 is loosely fitted around the outer circumference of the second connecting shaft 6 that supports the outer receiver 14, and this cylindrical body 15 is fitted and fixed in the shaft holes 3a, 3b of the second link member 3. Therefore, the gap between the cylindrical body 15 and the second link member 6 can be reduced to zero, and the shaft hole 1a of the base member 1, which is fitted in the fixed cylindrical body 15 and relatively rotatable with respect to the cylindrical body 15, can be reduced to zero. , 1b, it is possible to eliminate the rattling of the link mechanism A caused by allowing the second connecting shaft 6 for supporting the outer receiver to rotate freely. By providing a cylindrical body 15 fixed to the second link member 3 around the outer circumference of the connecting shaft 6, it is possible to prevent shearing loads from acting on the second connecting shaft 6 when the link mechanism A is deformed. This allows the second connecting shaft 6 and, by extension, the outer receiver 14 to rotate smoothly at all times.

In the embodiment described above, the outer receiver 1 is attached to the second connecting shaft 6 among the first to fourth connecting shafts 5 to 8.
4, but it may also be supported by one of the first, third, and fourth connecting shafts 5, 7, and 8. In this case, the cylindrical body 15 is fixed to one of two members in a link mechanism connected by an outer receiving connecting shaft, and is fitted to the other so as to be relatively rotatable.

In addition, in the above explanation, the first to fourth connecting shafts 5 to 8
Outer receiver 14 is attached to the connecting shaft that is free to rotate.
However, the wire fixture 13 may be supported in other ways, or the first to fourth connecting shafts 5 may be supported.
Two of the connecting shafts 8 to 8 may be freely rotatable, and one of these two connecting shafts may support the wire fixture 13, and the other may support the wire receiver 14, respectively.
In this case, the cylindrical body 15 is loosely fitted around the outer circumference of two rotatably provided connecting shafts.

Also, although what is illustrated is a rear derailleur, a front derailleur can also be constructed in the same way.

As described above, according to the present invention, one of the wire fixture and the outer receiver supported on at least one freely rotatable connecting shaft among the four connecting shafts that interconnect the four members of the link mechanism. , in a link mechanism in which a cylindrical body is loosely fitted around the outer circumference of the connecting shaft which can be freely rotated together with the connecting shaft and which is free to rotate, and the cylindrical body is connected by the connecting shaft which is freely rotatable; Since it is fixed to one of the two members and fitted to the other so as to be relatively rotatable, it is possible to eliminate the rattling of the link mechanism due to the free rotation of the connecting shaft. Therefore, there is no harm caused by having to make the operating stroke of the operating wire extra long.
Moreover, it is possible to accurately align the operating lever to a specific position.

Furthermore, by using the cylindrical body, when the link mechanism is deformed, it is possible to prevent shearing loads from acting on the freely rotatable connecting shaft, so that the freely rotatable connecting shaft always rotates by an appropriate amount. Therefore, it is possible to eliminate the negative effects of the operation wire being difficult to pull, the operation wire being easy to break, and the movement position of the chain guide being out of alignment. be.

[Brief explanation of the drawing]

Fig. 1 is a front view showing one embodiment of the derailleur of the present invention, Fig. 2 is a bottom view, Fig. 3 is a cutaway front view of the main part, and Figs. 4 and 5 are enlarged cross-sectional plan views of the main part. be. 1... Base member, 2, 3... Link member, 4
...Movable member, A...Link mechanism, 5-8...Connection shaft, 9...Chain guide, 16...Wire fixture, 14...Outer receiver, 15...Cylinder, W...
...Operating wire, O...Outer tube.

Claims (1)

[Scope of utility model registration request] A movable member having a base member, a pair of link members pivotally supported on the base member via a pair of connecting shafts, and a chain guide supported on these link members via a pair of connecting shafts. A derailleur is provided with a link mechanism consisting of four members, and the link mechanism is deformed by operation of an operating wire to move the movable member relative to the base member, wherein at least one of the four connecting shafts A connecting shaft is rotatable relative to the two members of the link mechanism connected by the connecting shaft, and a wire fixture for fixing the wire and an outer receiver of an outer tube for guiding the wire are attached to one end of the connecting shaft. a cylindrical body is loosely fitted around the outer circumference of the connecting shaft which is free to rotate, the cylindrical body is fixed to one of the two members, and is fitted to the other so as to be relatively rotatable. A bicycle dayrailer characterized by: