JP2009299831A - Disc brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disc brake for restraining brake noise in a slow braking by restraining uneven wear of a friction member. <P>SOLUTION: A Young's modulus on a disc rotation output side and a Young's modulus on a disc rotation input side of a brake pad 3 are adjusted, so as to minimize unevenness of a contact surface pressure in all areas of a lining 11. Thereby, wear of the brake pad 3, and unevenness of the surface pressure in all areas of the lining 11 is minimized, so as to restrain noise of a disc brake. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an improvement in a disc brake.

  For example, in a disc brake used in an automobile or the like, it is a technical problem to suppress squeal at a low pressure. In general, it is considered that the squeal of the disc brake is one of the causes that the contact surface pressure (hit) of the brake pad is not uniform. In the disc brake, a moment is generated in the brake pad by the braking force. Then, due to this moment, the contact surface pressure on the rotation inlet side of the brake pad becomes higher than the contact surface pressure on the rotation outlet side. For this reason, the amount of wear on the rotation inlet side is the largest. As described above, in the disc brake, the wear amount of the brake pad varies depending on the contact position. As a result, the behavior of the brake pad becomes unstable during braking, and a brake squeal occurs particularly during slow braking (hydraulic pressure applied to the disc brake is a slight pressure).

Therefore, Patent Document 1 discloses a disc brake pad in which a plurality of friction members having different friction characteristics formed in an arc shape with respect to the braking direction are alternately provided. However, also in this disc brake pad, the contact surface pressure on the rotation inlet side of the brake pad is still higher than the contact surface pressure on the rotation outlet side, and therefore, the amount of wear on the rotation inlet side is the largest. Therefore, the brake pad wear amount varies depending on the contact position. As a result, the behavior during braking becomes unstable, and there is a risk that brake squeal may occur during slow braking (the hydraulic pressure applied to the disc brake is a slight pressure).
Japanese Patent Laid-Open No. 10-299802

  Then, this invention makes it a subject to provide the disc brake which suppressed the brake squeal at the time of slow braking by suppressing the uneven wear of a friction member.

  In order to solve the above problems, the disc brake according to claim 1 of the present invention is such that the brake pad is formed of a single friction member having a different Young's modulus on the disk entry side and different Young's modulus on the disc delivery side. It is characterized by becoming.

  According to the present invention, the difference in the Young's modulus on the disk inlet side and the disk outlet side in the single friction member makes it possible to reduce the contact surface pressure difference of the brake pad, whereby the friction member Therefore, it is possible to provide a disc brake that suppresses brake squeal during slow braking.

An embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the disc brake 1 includes a pair of brake pads 3 (hereinafter referred to as inner brakes as required) disposed on both the inner and outer sides (the left and right sides in FIG. 1) of the disc rotor 2 (disc). The pad is referred to as the inner pad 3a, the outer brake pad is referred to as the outer pad 3b), the piston 4 facing the inner pad 3a, and the claw portion 5 and the piston 4 extending across the disk rotor 2 and facing the outer pad 3b are fitted. The caliper 13 in which the cylinder 6 is disposed, and the carrier 7 which is attached to the vehicle body side and supports the pair of brake pads 3 and the caliper 13 so as to be movable in the axial direction of the disc rotor 2 (left and right direction in FIG. 1). And having. A seal member 9 is provided in the bore 8 of the cylinder 6.

  As shown in FIG. 2, the brake pad 3 has a substantially arc-shaped pad plate 10 (back metal) extending along the rotational direction of the disk rotor 2. A lining 11 (friction member) is integrally provided on the lining mounting surface 10 a of the pad plate 10. In the disc brake 1, the piston 4 moves to the left in FIG. 1 with respect to the cylinder 6 by the pressure of the hydraulic fluid supplied from the master cylinder (not shown) to the bore 8 of the cylinder 6. As a result, the thrust of the piston 4 causes the cylinder 6 to move in the axial direction of the disk rotor 2 (the left-right direction in FIG. 1) as needed, while pressing the pair of brake pads 3 against the disk rotor 2 to apply braking force. appear.

Next, a method for manufacturing the brake pad 3 of the disc brake 1 will be described.
First, the material of the lining 11 (friction member) (hereinafter referred to as the lining material 11a) is uniformly mixed by a mixing device. Here, as the lining material 11a, for example, a binder, a fibrous substance, a filler, a friction adjusting material, or the like is used. There is no restriction | limiting about the component and mixing | blending of the lining material 11a, A well-known material can be used suitably. Next, as shown in FIG. 3A, the above-described lining material 11 a is put on the lining mounting surface 10 a of the pad plate 10 (back metal) set in the mold 12. Here, the amount of the lining material 11a on the side of the pad plate 10 on the disk delivery side (the exit side of the disk rotor 2 when the vehicle moves forward, the right side in FIG. 3A) is on the disk entry side. The pre-molded material is distributed more than the amount on the side (the entrance side of the disc rotor 2 when the vehicle moves forward and the left side in FIG. 3A).

  In this state, as shown in FIG. 3B, heating / pressure molding is performed under specified conditions (temperature, pressure, time, etc.). After the heating / pressure forming of the lining material 11a is completed, the lining 11 formed integrally with the pad plate 10 is fired under specified conditions. The brake pad 3 is cooled after firing, and the lining 11 is polished by a polishing apparatus. The brake pad 3 obtained in this way has a structure in which the disk feed-out side is denser than the disk feed-in side structure, so that the Young's modulus on the disk feed-out side is smaller than the Young's modulus on the disk feed-in side. Also grows. That is, the lining 11 (friction member) has a high rigidity region on the disk delivery side (right side with respect to the center in FIG. 2) and a low rigidity region on the disk introduction side (left side with respect to the center in FIG. 2). Become.

  In this embodiment, the contact surface pressure of the lining 11 in the brake pad 3 (hereinafter simply referred to as contact surface pressure) is adjusted by appropriately adjusting the Young's modulus on the disk delivery side and the Young's modulus on the disk delivery side. The entire surface of the lining 11, that is, the disk feeding side and the disk feeding side are made uniform to minimize the surface pressure difference as a whole. As a result, the wear of the brake pad 3 can be minimized in the entire surface of the lining 11 and the non-uniform surface pressure can be minimized (the contact surface pressure difference between the lining 11 and the disk rotor 2 can be reduced). The noise at the time can be suppressed. In order to minimize the non-uniform surface pressure over the entire area of the lining 11, the Young's modulus on the disk delivery side of the lining 11 is set to about twice the Young's modulus on the disk delivery side. Is the most effective.

This embodiment has the following effects.
According to this embodiment, the contact surface pressure of the lining 11 is adjusted over the entire area of the lining 11 by adjusting the Young's modulus on the disk delivery side and the Young's modulus on the disk delivery side of the lining 11 (friction member) of the brake pad 3. The non-uniform surface pressure was minimized. As a result, the wear of the lining 11 can be minimized in the entire surface of the lining 11 and the contact pressure difference between the lining 11 and the disc rotor 2 can be minimized. Can effectively suppress squealing. Furthermore, since uneven wear of the lining 11 is suppressed, the life of the brake pad 3 can be extended.
According to the present embodiment, when the lining 11 (friction member) is integrally formed on the pad plate 10 (back metal), the amount of the lining material 11a (friction member material) on the disk delivery side is set to the amount on the disk entry side. Allocated more than the amount. As a result, the lining 11 formed integrally with the pad plate 10 has a Young's modulus on the disk delivery side larger than the Young's modulus on the disk delivery side, and the contact surface pressure is reduced over the entire area of the lining 11. Uniformity can be minimized (the contact surface pressure difference between the lining 11 and the disk rotor 2 can be reduced).

  The embodiment is not limited to the above-described embodiment, and may be configured as follows, for example.

  The brake pad 3 may be configured by setting the porosity of the lining 11 (friction member) on the disk delivery side to be smaller than the porosity on the disk delivery side. As a result, the wear of the brake pad 3 can be minimized in the surface pressure non-uniformity throughout the lining 11 (the contact surface pressure difference between the lining 11 and the disk rotor 2 can be reduced), and the same effect as the above-described disk brake 1 can be achieved. Can be obtained. In this case, for example, the porosity of the lining 11 can be adjusted by adjusting the composition of the resin component in the lining material 11a (the material of the friction member). Further, when the lining 11 (friction member) is integrally formed on the pad plate 10 (back metal), the amount of the lining material 11a on the disk delivery side is larger than the amount on the disk entry side as in the above-described embodiment. It is not always necessary to distribute, and unevenness of the surface pressure can be distributed to the minimum. In addition, the porosity of the lining 11 can be raised by reducing the compounding of the resin component in the lining material 11a.

  The brake pad 3 may be configured by setting the friction coefficient on the disk delivery side of the lining 11 (friction member) larger than the friction coefficient on the disk delivery side. As a result, the wear of the brake pad 3 can be minimized in the surface pressure non-uniformity throughout the lining 11 (the contact surface pressure difference between the lining 11 and the disk rotor 2 can be reduced), and the same effect as the above-described disk brake 1 can be achieved. Can be obtained. In this case, for example, the friction coefficient of the lining 11 can be adjusted by adjusting the blending of friction adjusting materials such as zircon sand and alumina powder in the lining material 11a (material of the friction member). Further, when the lining 11 (friction member) is integrally formed on the pad plate 10 (back metal), the amount of the lining material 11a on the disk delivery side is larger than the amount on the disk entry side as in the above-described embodiment. It is not always necessary to distribute, and unevenness of the surface pressure can be distributed to the minimum. Note that the friction coefficient of the lining 11 can be increased by increasing the blending of the friction modifier in the lining material 11a.

  The brake pad 3 may be configured by setting the hardness of the lining 11 (friction member) on the disk delivery side larger than the hardness on the disk delivery side. As a result, the wear of the brake pad 3 can be minimized in the surface pressure non-uniformity throughout the lining 11 (the contact surface pressure difference between the lining 11 and the disk rotor 2 can be reduced), and the same effect as the above-described disk brake 1 can be achieved. Can be obtained. In this case, for example, the hardness of the lining 11 can be adjusted by adjusting the composition of the thermosetting resin component in the lining material 11a (the material of the friction member). Further, when the lining 11 (friction member) is integrally formed on the pad plate 10 (back metal), the amount of the lining material 11a on the disk delivery side is larger than the amount on the disk entry side as in the above-described embodiment. It is not always necessary to distribute, and unevenness of the surface pressure can be distributed to the minimum. In addition, the hardness of the lining 11 can be raised by increasing the compounding of the thermosetting resin component in the lining material 11a and baking. Further, in the firing process of the lining material 11a (material for the friction member), the hardness of the lining 11 can also be obtained by changing the heating conditions (heating time, heating temperature, etc.) between the disk inlet side and the disk outlet side of the lining material 11a. Can be adjusted.

It is sectional drawing which shows the structure of the disc brake of this embodiment. It is a top view of the brake pad of the disc brake of this embodiment. It is explanatory drawing of the disc brake manufacturing method of this embodiment. It is explanatory drawing of this embodiment, Comprising: It is a figure which shows the relationship between the tangential direction position and contact surface pressure in a brake pad.

Explanation of symbols

1 disc brake, 2 disc rotor (disc), 3 brake pad, 4 piston, 6 cylinder, 8 bore, 10 pad plate (back metal), 11 lining (friction member), 11a lining material (friction member material), 13 caliper

Claims (1)

A pair of brake pads disposed on both the inner and outer sides of the disc, a piston facing the inner brake pad, a claw portion extending across the disc and facing the outer brake pad, and the piston are fitted. And a carrier that is attached to the vehicle body and supports the pair of brake pads and the caliper so as to be movable in the axial direction of the disk, and the thrust of the piston A disc brake that generates a braking force by pressing the pair of brake pads against the disc,
The disc brake according to claim 1, wherein the brake pad is formed of a single friction member having a different Young's modulus on the disc feed-in side and Young's modulus on the disc feed-out side.

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