JPH1130251A - Mounting structure for guide pin to caliper in disc brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability of a split type guide pin in a pin slide type disc brake. SOLUTION: A flange 11 is arranged in the end of a guide pin 10, an external thread part 12 is arranged in front of the flange 11, and a bolt with a cap screw part is used for a mounting bolt 14 to be threadedly engaged with the external thread part 12. The external thread part 12 in the guide pin 10 and a cap screw part 14c in the mounting bolt 14 are inserted together into a bolt hole 15 in a caliper arm 13, and inside the bolt hole 15, the external thread part 12 is threadedly engaged with the cap screw part 14c in the mounting bolt 14, so that the guide pin 10 can be fixed to the caliper arm 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for attaching a split type guide pin to a caliper in a pin slide type disc brake, and to improve the fatigue resistance of the guide pin to improve its durability. You can do it.

[0002]

2. Description of the Related Art The relationship between a guide pin and a caliper of a pin slide type disc brake can be roughly divided into the following.
A type in which a guide pin is fixed to a support (a fixing member that supports a caliper and the like), and the caliper is slidably supported by the guide pin (for example, the actual open type 6).
And a type in which a guide pin is fixed to a caliper and the guide pin is slidably fitted in a support hole of a support (for example, Japanese Patent Application Laid-Open No. 7-310768).
The present invention is of the latter type, that is, a type in which a guide pin is fixed to a caliper. The split type guide pin in the latter type has one end in contact with the side surface of the caliper and is fixed to the caliper by a connecting bolt, and there are various types of mounting structures,
One example is described in the above-mentioned Japanese Patent Application Laid-Open No. 7-310768. This has the advantage that the structure is simple and the mounting and dismounting of the caliper can be performed simply and easily. Since this mounting structure is the premise of the present invention, its outline will be described with reference to FIGS. The mounting bolt 2 is inserted into the bolt hole 1b of the caliper arm 1a of the caliper main body 1, and the mounting bolt 2 is screwed into the screw hole of the guide pin 3 whose end surface is in contact with the inner side surface of the caliper arm 1a. The caliper 1 is fixed to the caliper arm 1a, and the guide pin 3 is slidably fitted in the guide hole 4a of the support 4 to support the caliper 1 on the support 4. In this structure, a screw hole is provided at one end of the guide pin, and the mounting bolt is screwed into this hole. Therefore, the root of the guide pin is weak against the bending moment due to the braking torque, causing fatigue failure and durability. There is a problem. This problem can be dealt with by making the guide pin 3 thick, but this is not practical because the guide pin 3 becomes thick and the diameter of the guide hole 4a of the support 4 becomes large. In the above-mentioned conventional device, a large-diameter portion 3a is provided at the base of the guide pin 3 in order to increase the strength of the base of the guide pin 3 while avoiding the above-described problem caused by making the guide pin 3 thick, and the base is made thick. doing. However, the above-mentioned conventional one has a guide pin
Since the large-diameter portion 3a at the root of the screw becomes thicker over a range longer than the length of the screw hole 3b, it is inevitable that the distance B between the caliper arm 1a and the support 4 becomes longer by the length of this portion. This also causes disadvantages such as an increase in bending moment applied to the root of the guide pin due to the braking torque.

[0003]

SUMMARY OF THE INVENTION The present invention relates to the above-mentioned conventional structure, in which a screw hole is not provided at an end of the guide pin in order to improve the durability of the guide pin. It is an object of the invention to devise

[0004]

Means taken to solve the above problem are as follows. A guide pin having one end fixed to a caliper arm is slidably inserted into a guide hole of a support so that the caliper is slidable on the support. , And the end of the guide pin is fixed to the caliper arm by screwing a mounting bolt to the end of the guide pin. Assuming a pin slide type disc brake, the following elements (a) to (c) are used. It is composed. (A) A flange is provided at the end of the guide pin, and a male thread is provided in front of the flange. (B) The mounting bolt is a bolt with a cap screw. (C) The male thread of the guide pin is provided. And inserting the cap screw portion of the mounting bolt into the bolt hole of the caliper arm, and screwing the male screw portion into the cap screw portion of the mounting bolt in the bolt hole to fix the guide pin to the caliper arm.

[0005]

[Operation] When the male screw portion of the guide pin and the cap screw portion of the mounting bolt are screwed together in the bolt hole of the caliper arm, the flange of the guide pin contacts the inner side surface of the caliper arm. The guide pin is fixed to the caliper arm. Therefore, only a simple tensile force acts on the male screw portion, and no bending moment acts. The root of the guide pin, that is, the portion to which the maximum bending moment is applied is solid, and there is no threaded portion on the outer peripheral surface, so the durability of the root is high. If the caliper arm bolt hole is a simple round hole, when removing the caliper from the support, the mounting bolt must be removed and the male screw part of the guide pin must be pulled out from the caliper arm bolt hole. The guide hole of the support may be made longer so that the guide pin can be pushed in by the length of the male screw portion. In order to avoid lengthening the length of the guide hole, the bolt hole of the caliper arm is formed as a C-shaped hole opened downward, and the width of this opening is slightly larger than the diameter of the male screw portion of the guide pin. do it. Then, the bolt hole can be removed upward from the male screw portion of the guide pin, and the bolt hole can be dropped and fitted into the male screw portion of the guide pin from above.

[0006]

[Embodiment] Next, a first embodiment will be described with reference to FIG. Since the structure of the disc brake itself is not different from the conventional one, only the portion according to the present invention is shown in the drawings. A flange (flange) 11 is provided at the base of the guide pin 10, and a male screw portion 12 is further provided to protrude. In this embodiment, the diameter of the guide pin 10 is 15 mm, and the diameter of the male screw portion is 18 mm. The thickness of the caliper arm 13 is 20 mm, and the length D of the male screw portion 12 is 21.5 mm.
The mounting bolt 14 has a hexagonal head 14a and a flange 14b.
The shaft portion 14c is a female screw threaded cap screw, and the length of the cap screw is equal to or slightly shorter than the thickness of the caliper arm 13. Support 16
The guide hole 17 is formed so as to have a margin by a length a, and the margin a is slightly longer than the length D of the male screw portion 12 of the guide pin 10. When the guide pin 10 is pushed into the guide hole 17 of the support 16 to the maximum and the caliper body is lowered with respect to the support 16, the bolt hole 15 of the caliper arm 13
The caliper can be lowered until it coincides with the leading end of the 0 male screw portion 12. Male thread 12 of guide pin 10
Is aligned with the bolt hole 15, the male screw portion 12 is inserted into the bolt hole of the caliper arm 13 while the guide pin 10 is pulled out from the guide hole 17. Next, the shaft portion (bag screw portion) 14c of the mounting bolt 14 is inserted from outside into the bolt hole 15 of the caliper arm 13, the male screw portion 12 of the guide pin 10 is screwed into the female screw, and the guide pin 10 is tightened by tightening. It is fixed to the arm 13. At this time,
Since the caliper arm 13 is sandwiched between the flange 11 of the guide pin 10 and the flange 14b of the mounting bolt 14, the guide pin 10 is firmly fixed to the caliper arm 13. When the mounting bolt 14 is removed and the guide pin 10 is pushed into the guide hole 17 of the support 16, the male screw portion 12 comes out of the bolt hole 15 of the caliper arm 13, so that the caliper can be pulled up and removed from the support. The second embodiment is a modification of the shape of the bolt hole of the caliper arm 13. The bolt hole 18 is a C-shaped hole with a lower end cut out and opened downward. The width b of the downward opening 18a is Male thread 1 of guide pin 10
2 is slightly larger than the diameter. As a result, the male screw portion 12 of the guide pin 10 can be inserted into and removed from the bolt hole through the opening 18a, so that the length of the guide hole 17 of the support 16 can be made shorter by the length a than that of the first embodiment. The caliper can be easily and easily attached to and detached from the support 16.

[0007]

[Effect] An external thread is protruded from the end of the guide pin, the shaft of the mounting bolt is turned into a cap screw, and both are inserted into the bolt holes of the caliper arm, and both are screwed together in the bolt holes. By fixing the end of the guide pin to the caliper arm, the strength of the base of the guide pin against the bending moment due to the braking torque can be improved without making the base particularly thick. Further, since it is not necessary to make the root of the guide pin particularly thick, the sliding part of the guide pin with respect to the guide hole of the support can be provided up to the root of the guide pin. The distance between the support and the support can be made as small as possible, and the braking torque reduces the bending moment applied to the base of the guide pin. Strength can be improved. Further, although the conventional one is a female thread, the threading of the guide pin of the present invention is a male thread. Therefore, the threading is easy and the manufacturing cost can be reduced accordingly.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment.

FIG. 2 is a front view of a main part of a second embodiment.

FIG. 3 is a sectional view of a conventional example.

FIG. 4 is a sectional view of a main part of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Caliper main body (Caliper) 1a, 13 ... Caliper arm 1b, 15 ... Bolt hole 2 ... Mounting bolt 3, 10 ... Guide pin 3a ... Large root of guide pin 3 Diameter part 3b Screw hole 4, 16 Support 4a, 17 Guide hole 11 Flange of guide pin 10 12 Male screw part 14 Mounting with cap screw Bolt 14a: Hex head 14b: Flange of mounting bolt 14 14c: Shaft (cap screw) 18: C-shaped bolt hole 18a: Opening of C-shaped bolt hole B: Caliper Distance between arm 1a and support 4 D: length of external thread 12 of guide pin 10 b: width of opening 18a

Claims (2)

[Claims] 1. A guide pin having one end fixed to a caliper arm is slidably inserted into a guide hole of a support, the caliper is slidably supported by the support, and a mounting bolt is screwed onto an end of the guide pin. In a pin slide type disc brake in which the ends of the guide pins are fixed to a caliper arm, a flange is provided at the end of the guide pin, a male screw portion is provided in front of the flange, and the mounting bolt is a cap screw. The male screw part of the guide pin and the cap screw part of the mounting bolt are both inserted into the bolt hole of the caliper arm, and the male screw part is screwed into the cap screw part of the mounting bolt in the bolt hole. The disc brake guide pin is attached to the caliper by fixing the guide pin to the caliper arm. 2. The bolt hole of the caliper arm is a C-shaped hole having an opening at the bottom, and the opening has a width slightly larger than the outer diameter of the male screw portion of the guide pin. 1. A structure for mounting the guide pin of the disc brake to the caliper according to 1.