JP2012246978A - Disk brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk brake device reducing brake noise while suppressing transfer of friction heat to brake fluid.SOLUTION: The disk brake device applies a braking force to a vehicle by holding a disk rotor 2 with a brake pad 6. A disk rotor friction material 2c is disposed on the outer side sliding surface 2a2 of the disk rotor 2, and a metal pad 6b2 is used for an outer pad 6. By disposing a metal pad higher in heat conductivity than the friction material on a vehicle body outside, the transmission of the friction heat is separated from the brake fluid, and consequently heat is hardly transmitted to the brake fluid. The metal pad 6b2 is disposed in the outer pad 6b provided in the vehicle body outside, and the outer pad approaches outside air to be cooled more easily. Thus, heat transmitted from the outer pad 6b to a support member 4 is lower than the friction heat.

Description

  The present invention relates to a disc brake device used in a vehicle brake device.

A disc brake device used in a vehicle is a brake device that applies a braking force to a vehicle by pressing a brake pad against an inner side and an outer side of a rotating disc rotor. This type of disc brake device uses a metal disc rotor with low vibration damping, and depending on the friction characteristics of the disc rotor and brake pad, self-excited vibration due to pad bending mode occurs and brake squeal occurs There are things to do.

  On the other hand, the disk brake device in Patent Document 1 conventionally has a configuration in which a friction material is fixed to the inner side and the outer side of the disk rotor, and both the inner side and outer side brake pads are metal pads. In the disc brake device with the above configuration, a friction material having a higher damping property than the metal disc rotor is fixed to the disc rotor, so that the damping performance against the disc rotor vibration is improved, and vibration suppression and brake squeal are reduced. It is thought that it is done.

JP-A-8-170669

  However, in the disc brake device described in Patent Document 1, since the metal having good heat transfer is used for the inner brake pad, the frictional heat generated during braking is transmitted to the brake fluid via the inner brake pad. There is an easy problem.

  In view of the above problems, an object of the present invention is to provide a disc brake device that reduces brake squeal while suppressing transmission of frictional heat to the brake fluid.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes a disk rotor made of metal that rotates together with a wheel, and an inner pad and an outer pad that are pressed against an inner side and an outer side of the disk rotor. The friction material is fixed to the outer side of the inner pad, the friction material is fixed to the lining of the inner pad, the metal pad is fixed to the lining of the outer pad, and the friction material of the inner pad is pressed against the inner side of the disc rotor, The metal pad of the pad is pressed against the friction material on the outer side of the disk rotor.

  According to the above configuration, the friction material having a higher damping property than that of the metal is provided in the disc rotor, so that the vibration of the disc rotor is easily attenuated, so that brake squeal can be suppressed. Further, since the metal pad is fixed to the outer pad, the frictional heat is more easily transmitted to the outer pad than the inner pad. At this time, since the outer pad is closer to the outside air than the inner pad and is easily exposed to the outside air, the heat dissipation is excellent. As described above, the frictional heat generated by the friction between the disc rotor and the inner pad and the outer pad is easily transmitted to the outer pad, and the frictional heat transmitted to the outer pad is easily released to the outside air. Furthermore, since the frictional heat is also radiated from the disk rotor, the frictional heat is not easily transmitted to the brake fluid. The inner side represents the inside of the vehicle body in the vehicle, and the outer side represents the outside of the vehicle body in the vehicle.

  In the second aspect of the invention, the end of the metal pad in the circumferential direction of the disk rotor is chamfered.

  According to the above configuration, since the metal pad is not easily worn against the friction material, the chamfering of the metal pad is not easily lost due to wear during friction between the friction material fixed to the disk rotor and the metal pad. Chamfering of the friction material is performed as a countermeasure against brake squeal during braking, but according to the above configuration, the effect of countermeasure against brake squeal persists because the chamfer is unlikely to disappear.

  According to a third aspect of the present invention, a thermoelectric element is provided on the outer side of the metal pad.

  According to the said structure, since the thermal radiation from the metal pad of an outer side can be converted into electricity with a thermoelectric element and collect | recovered, friction heat can be used effectively.

Schematic diagram of disc brake device 1 Side view of disk rotor 2 The figure which chamfered metal pad 6b2. Diagram showing heat insulating material with holes drilled in a metal plate The figure which covered thermoelectric element with metal pad 6b2

  Hereinafter, a disc brake device 1 of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a disc brake device 1 using the present invention. The disc brake device 1 includes a disc rotor 2 and a brake caliper 3.

  The disc rotor 2 provided in the disc brake device 1 is formed in a disc shape, and has a sliding portion 2a provided on the outer peripheral portion of the disc rotor 2 and a hat portion 2b joined to the inner peripheral portion of the sliding portion. is doing. The hat portion 2b is fixed to a wheel hub (not shown) provided on the vehicle body, and the disc rotor 2 rotates together with the wheels.

  The brake caliper 3 includes a mounting (not shown) and a support member 4. The mounting is fixed to the vehicle body, and the support member 4 is supported by the mounting so as to be movable in the axial direction of the disc rotor 2. Further, the support member 4 is disposed so as to straddle the disk rotor 2.

  The brake caliper 3 includes a brake pad 6, an inner pad 6 a is disposed on the inner side of the disc rotor 2 (the vehicle body side of the disc rotor 2), and an outer pad 6 b on the outer side (the non-vehicle body side of the disc rotor 2). Is arranged. When the inner pad 6a is pressed against the inner sliding surface 2a1 of the disc rotor 2 and the outer pad 6b is pressed against the outer sliding surface 2a2 of the disc rotor 2, braking force is applied to the vehicle.

  The support member 4 of the brake caliper 3 is configured as a floating type having one piston 5 for operating the inner pad 6a. The support member 4 includes a cylinder part 4a connected to a hydraulic circuit (not shown), and brake hydraulic pressure is sent to the cylinder part 4a via the hydraulic circuit. Due to the brake fluid pressure generated by the driver's braking operation, the piston 5 moves in the direction of pressing the inner pad 6a against the sliding portion 2a, whereby the inner pad 6a is pressed against the inner-side sliding surface 2a1 of the disc rotor 2. . Using the reaction force of the pressing, the claw portion 4b of the support member 4 moves in the direction of pressing the outer pad 6b against the sliding portion 2a, and the outer pad 6b is pressed against the outer side sliding surface 2a2 of the disc rotor 2. Accordingly, the inner pad 6a and the outer pad 6b are pressed against the sliding surfaces 2a1 and 2a2 of the disc rotor 2, respectively.

  Next, the disc rotor 2, the inner pad 6a, and the outer pad 6b of the disc brake device 1 of the present invention will be described. The disk rotor 2 is a metal disk rotor. As shown in FIG. 2, a disk rotor friction material 2 c is fixed to the outer sliding surface 2 a 2 of the sliding portion 2 a provided in the disk rotor 2.

  The inner pad 6a is a brake pad formed by the lining 6a1 and the friction material 6a2. The lining 6a1 is pressed by the piston 5, and the friction material 6a2 is pressed against the inner-side sliding surface 2a1 of the disc rotor 2. The outer pad 6b is formed of a lining 6b1 and a metal pad 6b2. The lining 6b1 is pressed against the claw portion 4b of the support member 4, and the metal pad 6b2 is pressed against the disc rotor friction material 2c provided on the inner side sliding surface 2a2 of the disc rotor 2. The friction material used for the disk rotor 2 and the brake pad 6 is made of a material having a lower thermal conductivity than the disk rotor 2 and the metal pad 6b2.

  Next, the operation of the disc brake device 1 having the above configuration will be described. When the brake pedal (not shown) is depressed by the driver, the brake fluid pressure is sent to the cylinder portion 4a via the fluid pressure circuit. The brake pad 6 is pressed against the sliding portion 2 a of the disk rotor 2 by the piston 5 and the support member 4. At this time, the brake pad 6 is pressed so as to sandwich the disc rotor 2, and a frictional force acts on the disc rotor 2 to perform braking.

  When braking is repeatedly performed, frictional heat is generated due to friction between the brake pad 6 and the disk rotor 2. The frictional heat generated from the disc rotor 2 and the brake pad 6 is also transmitted to the brake caliper 3 and the like, and is transferred to the brake fluid. When the brake fluid becomes high temperature, there is a possibility that a vapor lock phenomenon occurs.

  In the present invention, a friction material is fixed to the outer sliding surface 2a2 of the disk rotor 2, and a metal pad 6b2 is fixed to the lining 6b1 of the outer pad 6b. The metal pad 6b2 has better heat transfer than the friction material used for the inner pad 6a and the disk rotor 2, and the frictional heat generated during braking is easily transmitted to the metal pad 6b2, so that the frictional heat generated during braking is greater than that of the inner pad 6a. It is easy to be transmitted to the outer pad 6b using the metal pad 6b2. Further, since the outer pad 6b is closer to the outside of the vehicle body than the inner pad 6a, the outer pad 6b is easily exposed to the outside air, and the outer pad 6b that is heated by frictional heat is more easily cooled than the inner pad 6a.

  With the above configuration, the frictional heat generated during braking is easily transmitted to the outer pad 6b side far from the piston 5, and the frictional heat can be kept away from the piston 5 and thus the brake fluid. Furthermore, since the heat transmitted to the outer pad 6b is exposed to the outside air, it is easy to release to the outside air. Therefore, the frictional heat transmitted to the piston 5 via the support member 4 of the brake caliper 3 is lower than the frictional heat generated during braking. Further, since the frictional heat is also released from the disc rotor 2, the frictional heat is not easily transmitted to the brake fluid.

Further, in the present invention, since the friction material is fixed to the outer sliding surface 2a2 of the disc rotor 2, the damping performance of the disc rotor 2 itself is improved, and brake noise is suppressed.
Since the metal pad is fixed to the lining 6b1 of the outer pad 6b and the metal pad 6b2 is used for the outer pad, the natural frequency of the outer pad bending mode deviates from the brake squeal frequency band. As a result, the brake squealing force caused by the pad bending mode can be lowered and the brake squeal can be suppressed.

  As shown in FIG. 3, the brake pad 6 of the present invention may suppress brake squeal at the time of braking as a shape (chamfered shape 6 b 3) that chamfers the circumferential end of the disk rotor 2. Since the chamfered shape 6b3 is applied to the metal pad 6b2 in this manner, the disappearance of the chamfered portion during braking is suppressed, so that suppression of brake squeal during braking can be maintained.

  Further, the lining 6b1 of the outer pad 6b in the present invention may be used as the thermoelectric element 7. At this time, since the thermoelectric element 7 is provided between the metal pad 6b2 and the claw portion 4b of the support member 4, when frictional heat is transmitted to the outer pad 6b during braking, the high-temperature metal pad 6b2 and the metal pad It will contact the support member 4 having a temperature lower than 6b2. By generating power using the temperature difference between the metal pad 6b2 and the support member 4 with the above configuration, the frictional heat can be converted into electricity and recovered.

  Although it is possible to convert frictional heat into electricity by providing a thermoelectric element in the disk rotor 2, it is necessary to attach the thermoelectric element to the rotating disk rotor 2, so that wiring and the like are difficult. In the present invention, since the thermoelectric element 7 is provided on the outer pad 6b side provided in the brake caliper 3, it is easy to install wiring and the like for collecting the converted electricity.

  Further, since the thermoelectric element 7 itself has lower thermal conductivity than the metal pad 6 b 2, the frictional heat generated during braking is not easily transmitted from the metal pad 6 b 2 to the support member 4 via the thermoelectric element 7. Therefore, heat transfer to the brake fluid via the thermoelectric element 7 is suppressed.

  Further, a metal plate 8 with holes as shown in FIG. 4 may be provided between the metal pad 6 b 2 and the support member 4. According to the above configuration, since the cavity formed by drilling the metal plate 8 has a heat insulating effect, the frictional heat generated during braking is not easily transmitted from the metal pad 6b2 to the support member 4. Further, as shown in FIG. 5, the thermoelectric element 7 is covered with a metal pad 6b2, a thermoelectric element is provided inside the metal pad 6b2 of the disk rotor 2, and air is interposed between the metal pad 6b2 on the support member 4 side and the thermoelectric element 7. A layer may be provided.

DESCRIPTION OF SYMBOLS 1 ... Disc brake apparatus 2 ... Disc rotor 2a ... Sliding part 2a1 ... Inner side sliding surface 2a2 ... Outer side sliding surface 2b ... Hat part 2c ... Disc rotor Friction material 3 ... brake caliper 4 ... support member 4a ... cylinder part 4b ... claw part 5 ... piston 6 ... brake pad 6a ... inner pad 6a1 ... lining 6a2 ..Friction material 6b ... outer pad 6b1 ... lining 6b2 ... metal pad 6b3 ... chamfered shape 7 ... thermoelectric element 8 ... metal plate

Claims (3)

A metal disk rotor that rotates with the wheels,
An inner pad and an outer pad pressed against the inner side and the outer side of the disk rotor,
A friction material is fixed to the outer side surface of the disk rotor,
A friction material is fixed to the lining of the inner pad,
A metal pad is fixed to the lining of the outer pad,
The friction material of the inner pad is pressed against the inner side of the disk rotor,
The disc brake device according to claim 1, wherein the metal pad of the outer pad is pressed against a friction material on the outer side of the disc rotor.   The disc brake device according to claim 1, wherein the end of the metal pad in the circumferential direction of the disc rotor is chamfered. The disc brake device according to claim 1 or 2, wherein a thermoelectric element is provided on an outer side of the metal pad.