JPH08338460A - Brake pads for vehicle disc brakes - Google Patents

Abstract

(57) [Summary] [Purpose] Prevents cracks generated on the side surface of the friction material due to frictional heat during braking without increasing the number of steps. [Constitution] Resin mold friction material 5 fixed to the back plate 2
A high carbon friction material 6 having a carbon content higher than that of the resin mold friction material 5 is arranged on the outer peripheral surface of the disk rotor and the side surface on which the disk rotor is extended, and both are integrated by pressure thermoforming to be fixed to the back plate 2. To do.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake pad for a vehicle disc brake, and more particularly to a brake pad for a vehicle disc brake in which cracks are prevented from being generated on a side surface of a friction material of the brake pad.

[0002]

2. Description of the Related Art Generally, a brake pad made of a resin mold made of friction material is mixed with various raw materials such as phenol resin, various fibers, organic agents, metals, abrasives, lubricants, etc. to make the whole composition uniform. Then, it is preformed, placed on the back plate of the brake pad, and fixed to the back plate by pressure thermoforming.

By the way, the temperature of this type of friction material rises due to the frictional heat generated during the braking action, and this temperature rise is highest at the friction surface and decreases as the distance from the friction surface increases. Further, since the side surface of the friction material is exposed to air and is more easily cooled than the central portion, the temperature rapidly drops from the friction surface toward the back plate, and the friction material near the friction surface and near the back plate is This causes a large difference in the amount of thermal expansion, which causes cracks on the side surface of the friction material. Therefore, as a technique for preventing the occurrence of cracks, for example, Japanese Patent Laid-Open No. 6-5835.
There is one disclosed in Japanese Patent No. 0.

This is because the side surface of the friction material is coated with a material having better thermal conductivity than that, so that heat generated on the friction surface of the friction material is easily transferred to the side surface of the friction material through the coating material. The temperature difference between the side surfaces of the friction material is reduced.

[0005]

However, since this coating process is performed after the friction material is formed, the number of steps is increased and the thickness of the coating material is limited, so that it is not possible to sufficiently prevent cracks. It was

[0006] Therefore, an object of the present invention is to provide a brake pad for a vehicle disc brake, which has been subjected to crack prevention processing without increasing the number of steps.

[0007]

In order to achieve the above object, the present invention provides a brake pad for a vehicle disc brake, wherein a resin mold friction material is fixed to a back plate according to the invention of claim 1. A high carbon friction material having a carbon content higher than that of the resin mold friction material is disposed on at least the outer peripheral surface of the disk rotor and the side surface where the disk rotor is extended, and the high carbon friction material and the resin mold friction material are added. It is characterized in that it is integrated by pressure heat molding and fixed to the back plate, and in the invention of claim 2, the carbon content of the high carbon friction material is carbon fiber.

[0008]

[Working] According to the structure of claim 1, the heat generated on the friction surface of the friction material is easily transferred to the side surface of the friction material through the carbon content of the high carbon friction material, and the heat is generated near the friction surface and the back surface. It suppresses the temperature difference from the vicinity of the plate and prevents the occurrence of cracks. Further, according to the configuration of claim 2, the strength of the high carbon friction material can be improved by the carbon fiber and the occurrence of cracks can be prevented, and further, the bond between the resin mold friction material and the high carbon friction material can be strengthened.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below based on the embodiments shown in the drawings.

FIG. 1 shows a first embodiment of the present invention.
The brake pad 1 has a metal back plate 2 and a friction member 4 fixed to a disk rotor 3 that rotates integrally with a wheel. The friction material 4 is composed of a resin mold friction material 5 occupying 70% of the total area, and a high carbon friction material 6 provided on the disk rotor outer peripheral side surface and the disk rotor feeding side surface of the resin mold friction material 5. ing.

The resin mold friction material 5 is formed by mixing aramid fiber, rock wool, metal fiber, metal powder, ceramic powder, barium sulfate, carbon fiber and the like with phenol resin as a binder. The high carbon friction material 6 contains more carbon fibers as a carbon content than the resin mold friction material 5.

As for the high carbon friction material 6 and the resin mold friction material 5, the raw material of the resin mold friction material 5 is put in a mold, and further the disk rotor outer peripheral side surface and the disk rotor squeezing side surface of the resin mold friction material 5 are placed. , High carbon friction material 6
Raw material is put in and preformed, and both are integrally fixed to the back plate 2 by pressure thermoforming to form the friction material 4, or the preformed resin mold friction material 5 and the outer peripheral surface of the disc rotor. A preformed high carbon friction material 6 is arranged on the side surface of the disc rotor where the resin mold is placed.
The high carbon friction material 6 and the high carbon friction material 6 are integrated by pressure thermoforming and fixed to the back plate 2 to form the friction material 4.

Brake pad 1 constructed in this way
In a braking test conducted by the applicant of the present invention at intervals of 20 to 30 seconds, as shown in FIG. 2, the temperature A of the disc rotor outer peripheral side surface of the friction material 4 and the disc rotor feeding side surface is the conventional friction material temperature. It is lower than B and does not rise to the temperature range where cracks occur even after repeated braking.

This is because the heat generated on the friction surface of the friction material 4 is easily transferred to the disk rotor outer peripheral surface and the disk rotor squeezing side surface of the friction material 4 through the carbon fibers of the high carbon friction material 6 as a medium. This is because the temperature rise on the side surface of the material 4 is suppressed.

Therefore, the temperature difference between the frictional member 4 outer peripheral side surface and the disk rotor feeding side surface near the friction surface and the vicinity of the back plate is reduced, and the occurrence of cracks on the side surface of the friction material 4 can be prevented.

Further, the high carbon friction material 6 is improved in strength by the carbon fiber and can reduce the occurrence of cracks, and further, when integrated, the carbon fiber makes the bond with the resin mold friction material 5 stronger. .

Further, high carbon friction materials 6 are respectively arranged on the disk rotor outer peripheral surface and the disk rotor feeding side surface of the resin mold friction material 5, and both are integrated by pressure thermoforming and fixed to the back plate 2. Therefore, the high carbon friction material 6 can be manufactured without increasing the number of steps, and the thickness of the high carbon friction material 6 can be arbitrarily set.

FIG. 3 shows a second embodiment of the present invention.
In the brake pad 10, high carbon friction materials 12 are arranged on the disk rotor outer peripheral surface, the disk rotor entry side surface, and the disk rotor exit side surface of the resin mold friction material 11, respectively, and both are integrated by pressure thermoforming to perform friction. Material 13
And is fixed to the back plate 14.

With this configuration, in addition to the effects of the first embodiment, the brake pads that are arranged facing each other on both sides of the disk rotor can be shared.

FIG. 4 shows a third embodiment of the present invention.
In the brake pad 20, high carbon friction materials 22 are arranged on the disk rotor outer peripheral side surface, the disk rotor entry side surface, the disk rotor exit side surface, and the disk rotor inner peripheral side surface of the resin mold friction material 21, respectively, and pressurize both of them. The friction material 23 is integrally formed by molding and is fixed to the back plate 24.

FIG. 5 shows a fourth embodiment of the present invention.
The brake pad 30 is formed by inserting a radial slit 33 of the disc rotor 32 into a central portion of the friction material 31 and dividing the friction material 31 into a left friction material 31a and a right friction material 31b. High carbon friction materials 35 are respectively arranged on the outer peripheral side surface of the disk rotor and the side surface on which the disk rotor is extended of the friction material 34, and integrated by pressure thermoforming to form the friction material 31 and fixed to the back plate 36.

FIG. 6 shows a fifth embodiment of the present invention.
The brake pad 40 is formed by inserting a radial slit 43 of the disc rotor 42 into the center of the friction material 41 and dividing the friction material 41 into a left friction material 41a and a right friction material 41b. The high carbon friction material 45 is arranged on each of the disk rotor outer peripheral side surface, the disk rotor inlet side surface, the disk rotor outlet side surface, and the disk rotor inner peripheral side surface of the friction material 44, and integrated by pressure thermoforming to form the friction material 41. And is fixed to the back plate 46.

[0023]

As described above, the brake pad of the vehicle disc brake according to the present invention has the resin mold friction material adhered to the back plate, at least on the disk rotor outer peripheral side surface and the disk rotor extension side surface. Since a high carbon friction material having a higher carbon content than the friction material is arranged and both are integrated by pressure thermoforming and fixed to the back plate,
The heat generated on the friction surface of the friction material is easily transferred to the side surface of the friction material through the carbon content of the high carbon friction material, and the temperature difference between the friction surface and the back plate is reduced to cause cracks. Can be prevented. Further, it can be manufactured without increasing the number of steps, and the thickness of the high carbon friction material can be set arbitrarily.

Further, by using carbon fiber as the carbon content of the high carbon friction material, the strength of the high carbon friction material can be improved by the carbon fiber and the generation of cracks can be prevented. Furthermore, the resin mold friction material and the high carbon friction material can be prevented. Strengthen the bond with wood.

[Brief description of drawings]

FIG. 1 is a front view of a brake pad showing a first embodiment of the present invention.

FIG. 2 is a graph showing a temperature rise in a braking test of a brake pad of the present invention and a conventional brake pad.

FIG. 3 is a front view of a brake pad showing a second embodiment of the present invention.

FIG. 4 is a front view of a brake pad showing a third embodiment of the present invention.

FIG. 5 is a front view of a brake pad showing a fourth embodiment of the present invention.

FIG. 6 is a front view of a brake pad showing a fifth embodiment of the present invention.

[Explanation of symbols]

1, 10, 20, 30, 40 ... Brake pad, 2, 1
4, 24, 36, 46 ... Back plate, 3, 32, 42 ... Disk rotor, 4, 13, 23, 31, 41 ... Friction material, 5,
11, 21, 34, 44 ... Resin mold friction material, 6,
12, 22, 35, 45 ... High carbon friction material

Claims (2)

[Claims] 1. A brake pad for a vehicle disc brake having a back plate to which a resin mold friction material is fixed, wherein a resin mold friction material is provided on at least the disk rotor outer peripheral side surface and the disk rotor extension side surface rather than the resin mold friction material. Arranged high carbon friction material with high carbon content,
A brake pad for a vehicle disc brake, wherein the high carbon friction material and the resin mold friction material are integrated by pressure thermoforming and fixed to the back plate. 2. The brake pad for a vehicle disc brake according to claim 1, wherein the carbon content of the high carbon friction material is carbon fiber.