JPH05126177A - Disc brake device - Google Patents

Abstract

PURPOSE:To effectively radiate heat generated by friction of a disc rotor and a brake pad at the time of braking by a disc brake device, CONSTITUTION:A number of holes 24c, 25c of a predetermined depths are provided in facing surfaces of a pair of brake pads 24, 25 provided on both sides of a disc rotor 10 to pressor members 28, 29 toward the inside of a pair of brake pads 24, 25. Heat radiation plates 26, 27 where a number of metal pins 26d, 27d are formed are provided between the brake pad and the pressor member facing the holes in the brake pad. The pins are inserted into the holes, and the brake pad is set slidable to the pins. Heat generated by friction of the disc rotor and the brake pad is transmitted through the pins to a main body of a heat radiation plate, so heat is effectively radiated to open air from the main body of the heat radiation plate, thereby temperature rise at the brake pad is restricted, with fade ability of the disc brake improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a pair of brake pads on both sides of a disk rotor that rotates integrally with a wheel, and the brake pads are pressed by a pair of pressing members to the disk rotor side. The present invention relates to a disc brake device that brakes a wheel by frictionally engaging a wheel and a brake pad.

[0002]

2. Description of the Related Art Conventionally, a disc brake device of this type has a friction member and a back metal part provided with a plurality of slit grooves in the back metal part of a brake pad, as disclosed in, for example, Japanese Patent Laid-Open No. 60-189632. A ventilation hole is formed in the bonded portion of the and the heat generated by frictional engagement between the disc rotor and the brake pad is radiated to the atmosphere through the ventilation hole.

[0003]

In the case of the disc brake device described above, the friction member of the brake pad needs to withstand high surface pressure, high load and high temperature. Therefore, for example, asbestos having high heat resistance is used as the base material. It is formed using raw materials. However, this raw material has a low thermal conductivity, and heat generated by frictional engagement between the disc rotor and the brake pad during braking cannot be sufficiently transmitted to the back metal part, and the back metal part is provided with the slit groove for heat dissipation. There is a problem that the effects provided cannot be fully utilized. Further, by providing a plurality of slit grooves in the back metal part, the area of the adhesive surface between the back metal part and the friction member is reduced, and thus the shear strength of the adhesive surface between the two is reduced, so the width of the slit groove should be increased. However, the heat radiation effect due to the provision of the slit groove is further reduced. The present invention is intended to solve the above problems, and provides a disc brake device capable of efficiently radiating the heat generated by the friction between the disc rotor and the brake pad during braking of the disc brake to the atmosphere. With the goal.

[0004]

A structural feature of the present invention is that a pair of brake pads are provided on both sides of a disk rotor that rotates integrally with a wheel, and each brake pad is pressed by a pair of pressing members. In a disc brake device that presses each side, and brakes the wheels by frictional engagement between the disc rotor and the brake pad, a surface of the brake pad facing the pressing member has a predetermined depth toward the inside of the brake pad. A large number of holes are provided, and a pair of heat dissipation plates, in which a large number of metal pins are erected so as to face the large number of holes of the brake pad, are provided between the brake pad and the pressing member, and the pins are provided in the holes. The brake pad is inserted so that the brake pad can slide with respect to the pin.

[0005]

According to the present invention configured as described above, when the pair of pressing members press the pair of brake pads on both sides of the disc rotor toward the disc rotor,
The brake pad slides on the pin of the heat dissipation plate and frictionally engages with the disc rotor to brake the wheel. At this time, the heat generated by the frictional engagement between the disc rotor and the brake pad is efficiently transmitted to the main body of the heat dissipation plate through the many metal pins inserted into the many holes provided in the brake pad, and Since the heat is dissipated from the heat sink body into the atmosphere, the temperature rise of the brake pad is suppressed, and therefore the fade performance of the disc brake is improved.

[0006]

An embodiment of the present invention will be described below with reference to the drawings. 1 to 3 schematically show a disc brake device according to an embodiment of the present invention. The disc brake device includes a disc rotor 10 that is integrally rotatably attached to a wheel (not shown) between the piston 22 and the claw portion 21a of the caliper 21 which are assembled in the inner hole of the caliper 21. Piston 22 of disk rotor 10
An inner pad 24 is provided near the side in parallel with the disc rotor 10, and an outer pad 25 is provided in parallel with the disc rotor 10 on the side of the caliper claw portion 21a of the disc rotor 10. .. As shown in FIGS. 1 to 3, the pads 24 and 25 are rectangular friction members 24 a, which face the disk rotor 10.
25a and back metal parts 24b and 25b attached to the same friction member and having substantially the same shape as the friction member. A large number of holes 24c and 25c having a small diameter are formed. Friction member 24a,
25a is made of, for example, an asbestos resin mold material having high surface pressure, high load, and heat resistance to withstand high temperatures, and the back metal parts 24b and 25b are made of metal plates having good thermal conductivity. In addition, the back metal parts 24b, 25
Protrusions 24b ₁ and 25b ₁ are integrally provided on both sides of the lower end of b, and the inner pad 24 and the outer pad 25 can be laterally moved to the caliper mount 23 by the protrusions 24b ₁ and 25b _1. It is assembled.

Inner pad 24 and outer pad 25
A pair of heat sinks 26, 27 are provided on the outer side of the pad near the pads.
Is provided. As shown in FIGS. 1 to 4, the heat radiating plates 26 and 27 are made of a material having good thermal conductivity such as aluminum, and each pair of metal plates 26a and 27a and a large number of cooling plates interposed between the metal plates 26a and 27a. The fins 26b and 27b are fixed and assembled to the caliper mount portion 23 by the claw portions 26c and 27c integrally provided on both sides of the metal plate facing the pads 24 and 25. Then, on the surface of the metal plates 26 a, 27 a facing the pads 24, 25, a large number of holes 24 provided in the pads 24, 25 are provided.
A large number of metal pins 26d and 27d having a length corresponding to the depth of the hole are erected at positions facing c and 25c,
The pads 24 and 25 are slidable with respect to the pins 26d and 27d by inserting the pins into the holes 24c and 25c. Further, through holes 26e and 27 for inserting pressing members 28 and 29, which will be described later, into the heat dissipation plates 26 and 27.
e is provided. Note that the heat dissipation plate may have a shape in which, for example, four through holes are provided, as shown in FIG. 5, instead of providing two through holes.

The piston side pressing member 28 is a disk portion 28a.
And a pair of pressing portions 28b integrally attached to the inner surface of the disk portion at diagonal positions in the horizontal direction, and fixed to the piston 22 by a spring 28c attached to the outer surface of the disk portion 28a. Has been done. Pressing member 2 on the claw portion 21a side
9 is composed of a pair of pressing portions 29a, and the pressing portions 29a are fixed to the claw portions 21a by bolts 21a ₁ . The pressing members 28 and 29 press the brake pads 24 and 25 by inserting the pressing portions 28b and 29a into the pair of through holes 26e and 27e of the heat dissipation plates 26 and 27, respectively. The pressing force of the members 28 and 29 is not applied to the heat dissipation plates 26 and 27. The number of pressing parts of the pressing members 28 and 29 is appropriately changed according to the number of through holes of the heat dissipation plates 26 and 27.

Next, the operation of the embodiment configured as described above will be described. When hydraulic pressure is applied to the piston 22 during braking in the disc brake device, the piston 22
Moving forward in the right direction shown in FIG. 1, the inner pad 24 is pushed by the pushing member 28 and slides against the pin 26d of the heat radiating plate 26, and is pushed by the inner surface of the disc rotor 10. .. At the same time, the claw portion 21a of the caliper 21 pushes the outer pad 25 via the pushing member 29 by the reaction force of the pushing force of the piston 22, and the pad slides with respect to the pin 27d of the heat radiating plate 27 to the outside of the disc rotor 10. Pressed on the surface. As a result, the disc rotor 10 is pinched by both brake pads 24, 25 to brake the rotation,
Along with this, the rotation of the wheels is braked. At this time, the frictional heat generated by the friction between the disc rotor 10 and the brake pads 24, 25 is generated by the holes 24 of the brake pads 24, 25.
a heat radiating plate 26 having good thermal conductivity, which is inserted in the c and 25c,
The heat sink 2 through the 27 metal pins 26d and 27d
The heat is transmitted to the main body of the heat sink 6, 27 and is smoothly radiated from the heat sink 26, 27 to the atmosphere. Therefore, the accumulation of frictional heat on the brake pads 24, 25 is suppressed, and the temperature of the brake pads can be prevented from rising. Table 1 below shows the test results of the conventional disc brake device and the disc brake device according to the present invention. The maximum temperature of the brake pad at the time of the test is about 440 ° C. in the disc brake of the present invention, and the maximum temperature of the conventional example. It decreases to about 80% compared to 560 ° C. Further, the minimum friction coefficient during the test is 0.37, which is about 1.8 times the minimum value 0.21 of the conventional example.

[0010]

[Table 1]

As described above, according to the present invention, the temperature rise of the brake pad during braking can be suppressed lower than in the conventional case, so that the fade performance of the disc brake device is improved.

In the above embodiment, the friction member of the brake pad is made of a material having low thermal conductivity. However, the present invention is applied to the brake pad using a semi-metallic material having good thermal conductivity. May be applied. In this case, normally, in order to prevent vapor lock of the brake pipe, a heat barrier layer is provided between the friction member and the back metal portion, but according to the present invention, friction heat generated during braking is applied to the heat dissipation plate. Since the provided pins and the radiator plate body efficiently dissipate heat into the atmosphere and heat is not transmitted to the piston and vapor lock does not occur, it is not necessary to provide a heat barrier between the friction member and the back metal portion.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a disc brake device showing an embodiment of the present invention.

FIG. 2 is a partially cutaway plan view taken along line 2-2 of FIG.

FIG. 3 is a partially exploded perspective view of the disc brake device.

FIG. 4 is a cross-sectional view of a heat dissipation plate which is a main part of the disc brake device.

FIG. 5 is a cross-sectional view showing a modified example of a heat dissipation plate.

[Explanation of symbols]

10 ... Disc rotor, 21 ... Caliper, 21a ... Claw part, 22 ... Piston, 23 ... Caliper mount part, 24
... Inner pad, 25 ... Outer pad, 24c, 25c
... Holes, 26, 27 ... Heat sinks, 26d, 27d ... Pins, 2
8, 29 ... Pressing member.

Claims (1)

[Claims] 1. A pair of brake pads are provided on both sides of a disk rotor that rotates integrally with a wheel, and the brake pads are pressed toward the disk rotor by a pair of pressing members. In a disc brake device for braking a wheel by frictional engagement with, a number of holes of a predetermined depth are provided on the surface of the brake pad facing the pressing member, and a large number of holes of a predetermined depth are provided in the brake pad. A pair of heat radiating plates with a number of metal pins standing upright facing the holes are provided between the brake pad and the pressing member, the pins are inserted into the holes, and the brake pads are slid with respect to the pins. Disc brake device characterized by being movable.