JPH0542779U - Disk brake squeal prevention device - Google Patents

Abstract

(57) [Summary] [Purpose] This is a device that combines multiple shims and mounts them on the back surface of the back plate of the brake pad to prevent so-called squeal during braking of the disc brake. Even when the notch shim is thin enough, the shim does not deform due to the tangential force during braking. [Structure] A backup shim that constitutes a squeal prevention device in combination with a rubber-coated shim 2 that is placed on the back surface of the back plate 1a of the brake pad 1 is arranged on the back side of the shim 2 and a cutout for retaining lubricant is provided on the shim 2. It is composed of a non-notched shim 3 and a notched shim 4 that close the hole 2a. The non-notched shim 3 has a thickness that can withstand the tangential force during braking, and the notched shim 4 is fixed to the non-notched shim 3 by caulking, and the non-notched shim 3 reinforces the notched shim 4. Therefore, the notch shim 4 can be made as thin as possible to prevent squeaking from low frequencies to high frequencies without lowering the caliper performance (increasing the amount of brake fluid, etc.).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a squeal prevention device that is mounted on the back surface of a back plate of a disc brake pad to suppress so-called squeaking and noise during braking.

[0002]

[Prior Art]

 Known squeal preventing devices for disc brakes are shown in FIGS. 4 and 5. The device shown in FIG. 4 is a combination of a rubber coat shim 2 and a back-up shim (non-notched shim 3) of a thin metal plate between the back plate 1a of the brake pad 1 and the outer pawl (not shown) of the brake piston or the caliper. A lubricant such as grease is applied between the shims 2 and 3 with a shim interposed between them, but this does not show a sufficient effect on the low-frequency squeal that is found in non-asbestos pads.

On the other hand, the device shown in FIG. 5 is effective for preventing low-frequency squeaking and abnormal noise, and a backup shim (notched shim 4) is arranged on the back of the rubber coat shim 2 so that the cutout hole 4a and the like are provided. The notch shim 4 provided makes the surface pressure of the pad non-uniform and suppresses low frequency sounds. However, in this device, since the shim 4 does not function as a sealing plate for grease, it is not possible to provide the cutout hole 2a in the rubber coat shim 2 and hold the lubricant therein as in the device of FIG. Even if a lubricant is applied to the back plate, the lubricating effect does not last long, and so-called fatigue and peeling of the rubber coating layer on the surface occur at an early stage, and the squeal prevention effect is not sustained.

[0004]

[Problems to be solved by the device]

 In order to obtain only the features of the apparatus shown in FIGS. 4 and 5, it is conceivable to form a step on the back side of the backup shim that overlaps the back surface of the rubber coat shim by etching or the like to make the pad surface pressure distribution non-uniform. However, this method is expensive and impractical.

Therefore, as shown in FIG. 6, it was considered to use a combination of the non-notched shim 3 and the notched shim 4 as a backup shim. However, the step that makes the surface pressure distribution of the pad non-uniform must be extremely small from the viewpoint of preventing an increase in the amount of brake fluid. In the structure of FIG. 5, the notch shim 4 is made thin to meet the demand. Therefore, there was a problem that this very thin notch shim would be deformed when it was pressed against the torque receiving surface by the tangential force generated during braking.

[0006]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention proposes a back-up shim that is used in combination with a plurality of sheets.The non-notched shim that closes the cutout hole of the rubber-coated shim has a thickness that can withstand the tangential force during braking. In order to make the pad surface pressure non-uniform, the notch shim is caulked and fixed integrally.

[0007]

[Action]

 When the notch shim is fixed to the high-strength non-notch shim, the non-notch shim acts as a reinforcing material for the notch shim, so that deformation of the notch shim due to tangential force during braking is eliminated.

[0008]

【Example】

 1 and 2 show an embodiment of the present invention. As shown in the figure, the rubber coat shim 2 which is attached to the back surface of the back plate 1a of the brake pad 1 is provided with a cutout hole 2a for filling and holding grease or the like.

The backup shim has a non-notched shim 3 that closely contacts the back surface of the rubber-coated shim 2 and closes the cutout hole 2a, and a back end of the non-notched shim is pressed by an outer claw of a brake piston or a caliper. A notch shim 4 and these shims are fixed to each other as shown in FIG. In Fig. 3, a small cylinder 5 punched on the rear side is attached to the non-notched shim 3 and the caulking fixing method is adopted in which the tip of this cylinder is folded back and locked to the rear surface of the notched shim 4. The shims 3 and 4 may be fixed to each other by spot welding or the like.

As shown in FIG. 1, the notch shim 4 is not limited to the one shown in FIG. 3 in which a cutout hole 4a is provided to remove a part of the surface pressed by the brake piston or the like. It may have a simple notch.

Further, in the embodiment, the non-notched shim 3 is formed of a stainless plate having a thickness of 0.4 mm, and the notched shim is formed of a stainless plate having a thickness of 0.2 mm. Not limited.

In addition, as shown in FIG. 1, the elastic locking piece 6 for holding the backup shim on the back plate of the pad is provided in the non-notched shim 3 having a higher strength than the notched shim 4. Good. In the conventional device, this elastic locking piece is provided on the outermost shim. Therefore, when the notch shim 4 is on the outermost side as shown in FIGS. 5 and 6, the shim 4 is unnecessary. Although it had to be thicker, according to the present invention, the shim 4 does not need to be provided with such a locking piece, and the notch shim 4 is necessary because the shim 3 acts as a reinforcing material against the tangential force. The thickness can be minimized to avoid changing pad pressure and increasing brake fluid volume.

[0013]

[Effect of the device]

 As described above, in the squeal prevention device of the present invention, the non-notched shim serves as a reinforcing member to prevent the notched shim from being deformed, so that the notched shim is made as thin as possible to improve the caliper performance. It is possible to prevent squeaking from low frequencies to high frequencies without significantly deteriorating.

Further, the effect can be maintained for a long period of time, and further, the total thickness of the combination shim hardly increases, so that the present caliper can be mounted.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention.

2 is a cross-sectional view of the state in which the device of FIG. 1 is mounted on a brake pad.

FIG. 3 is a front view showing another example of the notch shim.

FIG. 4 is a perspective view showing an example of a conventional squeal preventing device.

FIG. 5 is a perspective view showing another example of a conventional squeal preventing device.

FIG. 6 is a view showing a squeal prevention device which is used without integrating a plurality of backup shims.

[Explanation of symbols]

 1 Brake Pad 1a Back Plate 2 Rubber Coat Shim 2a Cutout Hole 3 Notch Shim 4 Notch Shim 4a Cutout Hole 5 Cylindrical 6 Elastic Locking Piece

Claims (2)

[Scope of utility model registration request] 1. A squeal preventing device for a disc brake, wherein a rubber coat shim having a shape similar to that of the back plate of the pad is attached to the back face of the pad back plate, and a plurality of backup shims made of thin metal plates are attached to the back side of the shim. , The plurality of backup shims, which are composed of non-notched shims that block the lubricant retaining cutouts provided in the rubber coat shim and notched shims that make the surface pressure distribution of the pad uneven, are integrally fixed. A characteristic disc brake squeal prevention device. 2. The squeal prevention device for a disc brake according to claim 1, wherein the notched shim is arranged on the back side of the non-notched shim.