JPS6350502Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a caliper in a disc brake that is provided with a piston return device that returns a protruding piston to its original position when pads are replaced.

A caliper in a disc brake is held by a retainer on an anchor plate, and usually includes one or two sets of cylinders and pistons. This piston is pushed out by the hydraulic pressure of pressurized hydraulic oil introduced into the cylinder when the disc brake is activated, and presses the inner pad against one side of the rotor. On the other hand, the caliper moves in the opposite direction to the pressing direction of the piston due to this reaction force, and the outer end of the caliper presses the outer pad against the other side of the rotor, and braking is performed by sandwiching the rotor between the inner pad and the outer pad. In this case, the piston moves while elastically deforming the sealing material with a rectangular cross section that seals the inner wall of the cylinder and the outer circumferential surface of the piston. However, as the amount of wear of the pad as an abrasion material increases, the amount of movement of the piston increases. When the deformation limit of the sealing material is exceeded, it slips between the piston and the sealing material, and only the piston is formed to protrude. Therefore, when replacing the pads, even if you remove the caliper with the piston still attached to the worn pad, you will not be able to install a new product, that is, a pad that is not worn out. The piston must be returned to its original state. Returning this protruding piston is impossible by hand and requires appropriate jigs and tools. Therefore, the purpose of this invention is to provide a caliper for a disc brake that does not require the use of jigs by providing a piston return device that pushes back the piston protruding from the outer end of the caliper to its original position. It is something.

This invention will be explained in detail based on illustrated embodiments.

FIG. 1 is a sectional view of a conventional caliper. In the figure, 1 is a caliper main body, 2 is an outer end, 3 is a cylinder, 4 is a piston, 5 is a sealing material, 6 is an inner pad, 7 is a rotor, and 8 is an outer pad. The inner pad 6 is directly fixed to the inner pad back plate 9, and the open end of the piston 4 formed in the shape of a cylinder with a bottom comes into contact with the end surface of the inner pad back plate 9, and the extrusion of the piston 4 causes friction of the inner pad 6. The surface is rotor 7
is formed in such a way that it comes into contact with the On the other hand, the outer pad 8 is also directly fixed to an outer pad back plate 10, and this outer pad back plate 10 is pulled up by a spring 12 in a stepped mounting hole 11 provided at the outer end 2 of the caliper body 1. The pad holder 13 is formed so as to come into contact with the inner surface of the outer end 2. When the pads are worn out, the distance between the open end of the piston 4 and the inner surface of the outer end 2 of the caliper body 1 is shorter than when a new pad is installed. The pads cannot be replaced.

In this invention, as shown in FIG. 2, the stepped mounting hole 11 of the caliper 1 in the conventional example is modified and a piston return device is provided in this portion. That is, the outer end 2 of the caliper main body 1 is formed with a circular groove 14 that opens outward, and an internal thread 15 that is connected to the circular groove 14, and further opens on the inner surface of the outer end 2. A stepped groove portion 16 is provided and formed. In this case, the stepped groove 1
6 is formed to have a larger opening diameter than the internal threaded portion 15, and at the same time, the groove depth is formed to be sufficiently smaller than the thread length of the internal threaded portion 15. In addition, the circular groove part 1
The opening diameter of 4 is formed larger than the outer diameter of the threaded part of the internal threaded part 15.

On the other hand, a flange 17 having an outer diameter that fits loosely into the stepped groove 16 and a thickness that is slightly lower than the inner surface of the outer end 2 after being loosely fitted, and a flange 17 connected to the flange 17;
A plug body 20 is provided, which includes an external threaded part 18 that is threadedly engaged with the internal threaded part 15 of the outer end part 2, and a plug body 20 that is connected to the external threaded part 18 and forms a wrench fitting part 19. In this case, the external threaded part 18 of the plug body 20 is formed to have a longer screw length than the internal threaded part 15 of the outer end part 2 which is screwed into the outer threaded part 18, and the plug body 20 is returned and the flange part 17 is screwed into the outer end part 2. Even if the screw protrudes from the inner surface of the screw, the number of screw threads that engage the screw threads should not suddenly decrease.

Furthermore, an adjustment screw portion 21 is formed concentrically with the flange portion 17 inside the plug body 20, and an adjustment screw portion 21 is formed concentrically with the flange portion 17.
A mounting hole 22 connected to 1 and formed with a large diameter.
is formed, and a stepped portion 23 is formed at the connecting edge. Further, a hexagonal or octagonal wrench fitting hole 24 is provided connected to the mounting hole 22. This wrench fitting hole 24 is formed to open in the end face of the plug body 20 so as to form the inner side of the wrench fitting part 19 . In this case, the adjustment screw portion 21 is formed so that the screw portion is as long as possible and the screw portion diameter is large, so as to reduce the load on the screw surface.

This plug body 20 connects the wrench fitting part 19 to the stepped groove part 1 from the inside of the outer end part 2 of the caliper main body part 1.
6, and fix the inner threaded part 15 and the outer threaded part 18 of the outer end part 2 by screwing them together. After this state, like the caliper in the conventional example,
The pad holder 13 is pulled by the spring 12 provided in the attachment hole 22 of the plug body 20 to lock the outer pad back plate 10 to the inner surface of the outer end 2. When replacing worn pads, as shown in Fig. 3, remove the caliper main body 1 from the anchor plate, remove the pad holder 13, remove the outer pad 8 and the outer pad back plate 10, and replace the inner pad 6 and the pad holder 13. Remove the inner pad back plate 9. Then the rear outer end 2
A spacer 25 of an appropriate length is interposed between the inner surface of the piston 4 and the open end surface of the piston 4, and at the same time, a wrench is inserted into the wrench fitting hole 24 of the plug body 20.
The plug body 20 is projected so as to be unfitted and pressed against the spacer 25, and the piston 4 is restored to its original position. In this case, the short length of time just before restoration is
This is done by inserting a bolt into the adjustment screw part 21 of the plug body 20 while holding the spacer 25, so that the spacer 25 can be easily removed. Further, the piston 4 can be restored by using only the external threaded portion 18 of the plug body 20 or only the adjustment threaded portion 21 depending on the amount of wear on the inner pad 6 and outer pad 8. Further, depending on the width of the spacer 25, it may be easier to screw a bolt into the adjustment screw portion 21.

Since this invention is constructed as claimed in the claims of the utility model registration based on the above-described embodiment, the plug body itself can rotate and protrude inward from the outer end of the caliper body. Therefore, the piston can be pushed back using a wrench and a spacer without a special jig. In addition, an adjustment screw part is formed on the inside of the plug body, so
Minor adjustments to the piston can be made using only the adjustment screw. In addition, the adjustment screw part can be used even when the width of the spacer is short by using a bolt, so the disk has a practical piston return device that can easily push the piston back by providing a plug body. Brakes can be provided.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a conventional caliper, FIG. 2 is a cross-sectional view of the return device, and FIG. 3 is a cross-sectional view showing the caliper in use. Explanation of symbols, 1... Caliper body, 2...
Outer end, 3...Cylinder, 4...Piston, 6
... Inner pad, 7... Rotor, 8... Outer pad, 9... Inner pad back plate, 10
...Outer pad back plate, 12...Spring,
13...Pad holder, 15...Inner threaded part, 1
6...Stepped groove part, 17...Flame part, 18...External threaded part, 20...Plug body, 21...Adjustment screw part, 2
2...Mounting hole part, 23...Step part, 24...Wrench fitting hole part.

Claims (1)

[Scope of utility model registration request] At the outer end 2 of the caliper main body 1, the outer end 2
The flange 17 is inserted into the stepped groove 16 that opens on the inner surface, and the internal thread 15 of the outer end 2 formed in connection with the flange 17 is screw-fitted, and the thread length is longer than the internal thread 15. an outer threaded part 18 formed long, a wrench fitting part 19 formed in connection with the outer threaded part 18, and an outer pad back plate 1 formed concentrically with the collar part 17.
The pad holder 13 that locks the piston 4 is loosely fitted therein, and the adjusting screw part 21 has a threaded part that engages with a bolt that pushes back the piston 4 on the inner peripheral surface. A mounting hole 24 is provided with a large diameter and is used to install the spring 12 that applies tension to the tool holder 13; A caliper for a disc brake, characterized in that a plug body 20 is provided with a wrench fitting hole 24 formed in an angular surface that fits into the end of a wrench to be rotated.