JPH0352627Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a side-pull caliper brake for bicycles.

(Prior technology) A side-pull type caliper brake was developed in 1985 to ensure equal braking distance between the left and right brake shoes and the rim, eliminate one-sidedness of the brake, and ensure braking action. It was proposed as No. 41946 and has shown excellent practical effects.

(Problem to be solved by the invention) In the caliper type brake of the above-mentioned Japanese Patent Publication No. 55-41946, the return spring engaged with the large and small caliper arms rotatably fitted to the pivot shaft is provided in an exposed manner. The legs of the spring are engaged with spring receivers protruding from the back surfaces of both arms. For this reason, during braking operation, both legs of the return spring slide against the spring receiver, creating a large frictional resistance at these opposing parts, making the brake operation extremely heavy. The anti-one-handedness effect it had was diminished due to this. Of course, in order to solve this problem, it is possible to adopt a structure in which a synthetic resin layer is provided on the outer peripheral surface of both legs of the return spring and placed opposite to the spring receiver, as disclosed in Japanese Utility Model Publication No. 51-25416. However, in any case, since the return spring is provided in an exposed manner, its function deteriorates due to adhesion of sludge and rust, making it unsuitable for long-term use, and it is also undesirable in terms of appearance.

(Means for Solving the Problems) The present invention improves the caliper type brake of the above-mentioned conventional patent publication No. 55-41946 by always maintaining an equal play between the left and right brake shoes and the rim, making the operation easier. The purpose is to provide a brake that is good in appearance and has a good appearance.As a means to achieve this purpose, large and small arms 5 and 8, which are rotatably fitted to the pivot shaft 1, are attached to the frame. A locking arm 12 is provided in which the base is pivotally supported by the pivot shaft 1 in a semi-fixed state, and a through hole 12a is provided at the tip of the locking arm 12, and the through holes 12a are provided in the large and small arms 5 and 8, respectively. Bottomed holes 5a and 8a facing each other are provided, and a swelling ball portion 15a is provided in the center
, and a swollen ball portion 15 at each end.
The central swollen ball portion 15a of the universal joint lever 15 formed with bulges b and 15b is inserted into the through hole 12a of the locking arm 12, and the swollen ball portions 15b and 15b at both ends are inserted into the large and small arms 5 and 8, respectively. In the caliper brake fitted into the bottom holes 5a, 8a, a coiled return spring 17 is loosely fitted on the pivot shaft 1 on the rear side of the small arm 8 to fix the front leg 17a to the small arm 8. At the same time, a spring cover 1 that covers the return spring 17 and whose front end surface is in contact with the rear surface of the small arm 8
6, abuts on the pivot shaft 1 at the rear end side of the cover 16, and has an adjustment arm 20 at one end thereof.
The rear leg 17b of the return spring 17 is loosely fitted into the spring adjustment body 20 with an extended length b.
is fixed, and the adjustment arm 20 of the spring adjustment body 20 is fixed.
Adjustment screw 2 with the end of b provided on the rear surface of the large arm 5
3 was adopted.

(Operation) When you operate the bicycle's brake lever and pull the inner wire (not shown), the large and small arms 5 and 8
As the wheels rotate in opposite directions, the left and right brake shoes 7 and 10 come into pressure contact with both sides of the rim to apply the brakes. At this time, the universal joint lever 15 and locking arm 12 before and after applying the brake in a normally installed state where the gaps between the brake shoes 7 and 10 on both sides and the rim are equal on both sides.
The operation of the joint lever 15 and the locking arm 12 when the brake is applied to restore the normal mounting state when one brake shoe comes into contact with the rim when the brake is released is as follows: The special public service of 1975, which was mentioned earlier as a conventional example.
Since it is explained in detail in No. 41946, its explanation will be omitted.

Next, the action of the return spring 17 and the strength adjustment of the return spring 17 by the spring adjustment body 20 will be explained with reference to FIG.

The return spring 17 has a front leg 17a fixed to the small arm 8 and a rear leg 17b fixed to the large arm 5 via a spring adjustment body 20, so that the inner wire can be pulled by operating a lever. As a result, the large and small arms 5 and 8 act on the return spring 17 in the tightening direction, and while resisting this elastic force, rotate about the pivot shaft 1 so that the brake shoes 7 and 10 are in the approaching direction. Conversely, when the brake is released, the return spring 17 acts in the opposite manner to that described above, causing the large and small arms 5, 8 to rotate the brake shoes 7, 10 in the direction of separation.

Next, the operation of adjusting the strength of the return spring 17 will be explained with reference to FIG. 4.
The engaging piece 20 with the hole is rotated in the direction of the arrow against the
c is brought close to the locking step 21 of the large arm 5, and the adjusting screw 23 is screwed into the screw hole 22 provided in the step 21 through the through hole provided in the engagement piece 20c. At this time, as the threading of the screw 23 into the screw hole 22 becomes deeper, the elastic force of the return spring 17 becomes larger.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 4. Fig. 1 is a sectional view of the main parts, Fig. 2 is an exploded perspective view seen from the front, Fig. 3 is an exploded perspective view seen from the rear, and Fig. 4 is a front view, explaining the adjustment action of the spring adjustment body. are also shown.

1 is a pivot shaft, and the coaxial shaft 1 has a head 1a, a large diameter part 1b, a medium diameter part 1c, and a small diameter part 1d formed from the front part,
A tool engagement hole 1e is formed at the front end of the head 1a, and a cap 2 is configured to be able to be fitted freely.The rear half of the small diameter portion 1d is a screw shaft 1f, and this screw shaft 1f is a fork crown of a bicycle. 3 is penetrated by a through hole 4 which is provided in the front and back in the central part of the body.

5 is a large arm rotatably fitted to the large diameter portion 1b of the pivot shaft 1; 6 is a pivot shaft insertion hole provided at the pivot position of the large arm 5; and 7 is attached to the tip of the large arm 5. This is the brake shoe. A small arm 8 is rotatably fitted to the middle diameter portion 1c of the pivot shaft 1, and has a pivot shaft insertion hole 9 at its base and a brake shoe 10 at its tip. Note 11
is a washer interposed between the large arm 5 and the head 1a of the pivot shaft 1. A locking arm 12 is located between the large arm 5 and the small arm 8 and is pivotally supported through an insertion hole 12b provided at the base of the pivot shaft 1 via washers 13 and 14. A through hole 12a is provided at the tip of the locking arm 12, and bottomed holes 5a, 8 are provided in the large arm 5 and the small arm 8, respectively, facing the through hole 12a.
The central bulging ball part 15a of the universal joint lever 15 has a bulging ball part 15a formed in the center and bulging ball parts 15b, 15b formed at both ends, respectively, through the through hole 12a of the locking arm 12. At the same time, both ends of the swollen ball portion 15
b, 15b are fitted into the bottomed holes 5a, 8a of the large and small arms 5, 8, respectively.

The above configuration is disclosed in Japanese Patent Publication No. 55-41946 mentioned above and is well known.

Reference numeral 16 denotes a spring cover rotatably provided on the small diameter portion 1d of the pivot shaft 1 on the rear side of the small arm 8, and the cover 16 is a bottomed cylindrical body with double walls, inside and outside, with an open rear surface. A coiled return spring 17 is inserted between the double walls of the cylindrical body. The front leg 17a of the spring 17 bent in the direction along the pivot shaft 1 passes through the through hole 16a provided at the bottom of the front surface of the cover 16, further passes through the shim 18, and is bored into the rear surface of the small arm 8. It is inserted and fixed into the provided hole 8b. A shim 19 is provided in contact with the rear end surface of the spring cover 16, and a spring adjustment body 20 is loosely fitted onto the small diameter portion 1d of the pivot shaft 1 on the rear surface of the shim 19. This spring adjustment body 20 is provided with a through hole 20a through which the rear leg 17b bent in the direction along the pivot axis 1 of the return spring 17 is inserted and fixed. Through hole 20a
It is fixed by interlocking with. Further, the spring adjusting body 20 has an adjusting arm 20b bent from one end, for example, the outer periphery, along the front of the pivot shaft 1, and the tip of the arm 20b is further bent to form an engaging piece 20c with a hole. ing.

Reference numeral 21 denotes a locking step provided near the pivot shaft 1 on the rear side of the large arm 5, and this step 21 is provided with a screw hole 22 in the vertical direction to adjust the engaging piece 20c with the hole. engages with the screw 23;
It is said that it can be adjusted freely via the spiral.

A nut 24 fastens the spring cover 16 and the spring adjustment body 20 via a washer 25;
6 is a nut fixed on the back side of the fork crown 3.

Next, another embodiment of the present invention will be explained with reference to FIG.
In the above embodiment, the spring cover 16
The spring cover 1 shown in FIG.
6 is a simple cylindrical body made of a hard wear-resistant resin material such as nylon. Furthermore, although the shims 18 and 19 are used in the embodiment described above, they are not used in this embodiment. Note that the spring cover 16 in both embodiments may be filled with grease.

(Effects of the invention) The present invention has a locking arm 12 provided between the large and small arms 5 and 8, and a universal joint lever 15 provided on the tip of this locking arm 12 and the large and small arms 5 and 8. The return spring 17 of the caliper type brake, which always maintains an equal play between the brake shoes 7, 10 and the rim, is coiled, and this is attached to the pivot shaft 1.
The front leg 17a is fixed to the small arm 8, the rear leg 17b side is fixed to the large arm 5 via the spring adjustment body 20, and the return spring 17 is covered with the spring cover 16. Unlike conventional return springs, there is no frictional resistance at all and the return spring can operate easily, and there is no unpleasant noise such as squeaks caused by friction.
As a result of eliminating the unilateralism due to the magnitude of frictional resistance between both legs, this is excellent in that the unique effects of using the locking arm 12 and the universal joint lever 15 are not diminished. Moreover, since the return spring 17 is covered by the cover 16 as described above, the spring 17 is protected from sludge, etc., and has a good appearance.
If grease is filled in 6, rusting can be effectively prevented.

[Brief explanation of the drawing]

1 to 4 show embodiments of the present invention.
The figure is a sectional view of main parts, Figure 2 is an exploded perspective view seen from the front, Figure 3 is an exploded perspective view seen from the rear, and Figure 4 is a front view, together with an explanation of the adjustment action of the spring adjustment body. FIG. 5 is a drawing corresponding to FIG. 1, showing another embodiment of the present invention. 1...Pivot shaft, 5...Large arm, 5a...Bottomed hole, 7...Left brake shoe, 8...Small arm,
8a...Bottomed hole, 8b...Hole, 10...Right brake shoe, 12...Locking arm, 12a...
...Through hole, 15...Universal joint lever, 15a...Central swelling ball part, 15b...Both end swelling ball parts, 16...Spring cover, 17...Return spring, 20...Spring adjustment body, 20b
...adjustment arm, 23...adjustment screw.

Claims (1)

[Claims for Utility Model Registration] A locking arm 1 whose base is semi-fixed to a frame and pivoted by the pivot shaft 1 to large and small arms 5 and 8 which are rotatably fitted to the pivot shaft 1.
A through hole 12a is provided at the tip of the locking arm 12, and large and small arms 5 and 8 are provided.
A bottomed hole 5 facing the through hole 12a, respectively.
a, 8a are provided, and a swelling ball part 15a is formed in the center, and swelling ball parts 15b, 15b are provided at both ends, respectively.
The central swollen ball portion 15a of the universal joint lever 15 formed with the locking arm 12
In the caliper brake, the caliper brake is fitted into the through hole 12a of the small arm 8, and the swollen ball portions 15b and 15b are fitted into the bottomed holes 5a and 8a of the large and small arms 5 and 8, respectively. A coiled return spring 17 is loosely fitted onto the support shaft 1 and its front leg 17a is fixed to the small arm 8, and the return spring 17 is covered and the front end surface is in contact with the rear surface of the small arm 8. Spring cover 1
6, abuts on the pivot shaft 1 at the rear end side of the cover 16, and has an adjustment arm 20 at one end thereof.
The rear leg 17b of the return spring 17 is loosely fitted into the spring adjustment body 20 with an extended length b.
is fixed, and the adjustment arm 20 of the spring adjustment body 20 is fixed.
Adjustment screw 2 with the end of b provided on the rear surface of the large arm 5
A side-pull type caliper brake characterized by engaging 3.