JP2003214465A - Disc rotor for brake and bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disc rotor for brake having an excellent suppressing effect for brake squeaking. <P>SOLUTION: The disc rotor 5 in rotation is braked by pressure contact of brake pads 7a and 7b, and in the ring-shaped inside part of the rotor where the pads are in slide contact, a heat resistant oil 21 is encapsulated which absorbs and damps the high-frequency vibrations inherent in the disc rotor generated in association with the pressure contact of the pads. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc rotor for a brake and a bearing device using the disc rotor. In this bearing device, a disk rotor is attached to a radially outward flange provided on a hub wheel.

[0002]

2. Description of the Related Art The phenomenon of brake squeal that occurs when braking a wheel of an automobile, an aircraft, a train, etc. is considered to be one of the causes of the high frequency vibration of the disc rotor due to the friction when the brake pad slides on the disc rotor. Has been. Various measures have been taken so far for suppressing or eliminating such brake squeal. For example, a vibration suppressing mechanism in which a wedge ring is fitted in a disk rotor (see JP-A-7-208517) or a vibration suppressing mechanism using a weight and an elastic member (JP-A-7-167) is used.
No. 176 and Japanese Patent Laid-Open No. 8-128473), a technique for forcibly suppressing high frequency vibration of the disk rotor is proposed.

[0003]

When a brake pedal of an automobile or the like is depressed to generate a high frequency vibration in the disc rotor, the amplitude of the high frequency vibration can be attenuated at high speed in order to suppress the brake squeal. preferable. However, in the conventional vibration suppressing mechanism, it takes a relatively long time to operate the vibration suppressing mechanism in response to the high frequency vibration of the disk rotor, and the brake squeal is not suppressed when the high frequency vibration occurs. It is thought that there is a risk.

Therefore, it is an object of the present invention to provide a disc rotor for a brake, which is capable of damping high-frequency vibrations of the disc rotor at a high speed, and is excellent in suppressing a brake squeal phenomenon, and a bearing device using the same.

[0005]

SUMMARY OF THE INVENTION The present invention is a brake disc rotor whose rotation is braked by pressure contact of a brake pad, the pressure contact of the brake pad being inside an annular portion with which the brake pad slides. By adopting a structure in which a vibration absorbing material that absorbs and attenuates the high frequency vibration peculiar to the disk rotor that occurs with
The high frequency vibration of the disk rotor can be damped at high speed, and an excellent effect of suppressing brake squeal can be obtained.

Further, when the vibration absorbing material is a liquid such as oil, the high frequency vibration waveform of the disk rotor becomes gentle, and it becomes difficult for the brake pad to resonate even when pressed against the brake pad.
The brakes are hard to squeal.

The annular portion is provided with an annular hollow portion which is continuous in the circumferential direction or a plurality of hollow portions which are distributed in several places around the circumference. The vibration absorbing material is enclosed in the hollow portion. If the heat-resistant oil is used, the vibration absorption performance does not decrease even with the temperature rise, and brake squeal can be suppressed for a long period of time.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The details of the present invention will be described below based on the embodiments shown in the drawings.

1 to 3 show an embodiment of the present invention. FIG. 1 is a vertical cross-sectional view of a bearing device according to an embodiment, FIG. 2 is a partially cutaway perspective view of the disc rotor shown in FIG. 1, and FIG. 3 is a diagram showing vibration waveforms of a brake pad and a disc rotor.

First, referring to FIG. 1, 1 is a bearing device,
2 is a hub wheel, 3 is a double row rolling bearing, 4 is a drive shaft, 5 is a disc rotor, 6 is a knuckle, 7a and 7b are brake pads, 8 is a bolt, 9
Is a nut.

The bearing device 1 comprises a hub wheel 2 and a double row rolling bearing 3 fitted onto the hub wheel 2. The drive shaft 4 is inserted and coupled to the center hole 2a of the hub wheel 2 so as to be integrally rotatable in the circumferential direction.

The double row rolling bearing 3 has one inner ring 3a having a single track fixed to the outer peripheral surface of the hub wheel 2 by external fitting, and a single outer ring 3b having two rows of track grooves. A plurality of balls 3c, 3c arranged in rows and two crown-shaped cages 3d, 3d are provided, and the large-diameter outer peripheral surface of the hub wheel 2 is the other inner ring. Further, the flange 12 radially outward with respect to the outer peripheral surface of the outer ring 3 b of the double row rolling bearing 3.
Is provided, and the knuckle 6 which is a part of the vehicle body is attached to the flange 12.

A radially outer flange 13 for mounting the disk rotor 5 and the wheel wheel 10 is provided at the vehicle outer side end portion of the large diameter outer peripheral surface of the hub wheel 2.

Bolt through holes 14 are provided at several circumferential positions of the flange 13 along the axial direction. Also,
Bolt insertion holes 15 along the axial direction corresponding to the bolt through holes 14 are also provided at several circumferential positions on the inner diameter side of the disk rotor 5.

In the present embodiment having the above structure, in order to suppress brake squeal in the disc rotor 5,
The brake pads 7a, 7b are provided inside the annular portion of the disc rotor 5 which is in sliding contact with the brake pads 7a, 7b.
It is characterized by having a vibration damping structure in which oil 21 is sealed as a vibration absorbing material for absorbing and attenuating the vibration peculiar to the disk rotor 5 generated by the pressure contact of b. The cross-sectional shape of the disk rotor 5 on the outer diameter side has a bent loop shape so as to form a katakana "B" shape, and the annular hollow portion 20 is secured in this loop. In this case, the annular hollow portion 20 is continuous in the circumferential direction, but it is not limited to this and may be distributed in several places in the circumferential direction. Although not shown in the drawing, this distribution structure may be a structure in which partition walls are provided in the annular hollow portion 20 at several positions in the circumferential direction.

The annular hollow portion 20 has a volume capable of enclosing a required amount of oil 21. It is preferable that the volume of this volume be able to contain the oil 21 in an amount capable of damping high-frequency vibration of the disk rotor 5 at high speed. The size of the volume of the annular hollow portion 20 and the type of the oil 21 are appropriately determined by experiments.

A refueling port 23 is provided at a required position on the rotor wall forming the annular hollow portion 20, and a refueling lid 24 is opened from the refueling port 23 so that the oil 21 can be injected into the annular hollow portion 20. It has become. The oil supply port 23 may be in the form of a grease nipple, and when using the grease nipple, it is preferable to provide a balancer so as to balance the rotation.

Next, the operation of this embodiment will be described with reference to FIG. FIG. 3A shows a vibration waveform of the brake pads 7a and 7b, and FIG. 3B shows a vibration waveform of the disc rotor 5. In these figures, the horizontal axis represents frequency and the vertical axis represents vibration level. As shown in FIG. 3A, the brake pads 7a, 7
The vibration waveform of b sharply rises, while in FIG.
As shown in (b), that of the disc rotor 5 has a vibration waveform such that the whole rises gently. The disk rotor 5 has such a vibration waveform because the oil 21 is sealed inside.

Since the disc rotor 5 has such a vibration waveform, when the disc rotor 5 is brought into sliding contact with the brake pads 7a and 7b along with the brake operation, the high frequency vibration of the disc rotor 5 is caused by the oil 21 at high speed. At the same time, the disc rotor 5 is less likely to resonate and the brake squeal is less likely to occur.

In this case, the more the natural vibration waveform of the disk rotor 5 increases, the more difficult the brake squeal occurs. Further, as the resonance point of the disc rotor 5 with respect to the brake pads 7a, 7b is further displaced, the brake squeal is attenuated at a higher speed.

In the above embodiment, the oil 21 is used as the vibration absorbing material, but the vibration absorbing material may be solid, fluid, semi-fluid or liquid.
Examples of the solid vibration absorber include soft rubber and resin having flexibility. In the case of resin, it may be foamed resin, for example, styrene foam resin.

Further, in the disk rotor 5, the portion where the brake pads 7a and 7b are in sliding contact rises to a considerably high temperature depending on the braking state. Therefore, the vibration absorbing material serves to absorb vibration even in such a high temperature state. Those whose performance does not change, such as heat resistant oil, are preferred.

[0023]

As described above, according to the present invention,
A disc rotor whose rotation is braked by pressure contact of a brake pad, wherein a high frequency vibration peculiar to the disc rotor generated due to the pressure contact of the brake pad is absorbed and attenuated inside an annular portion with which the brake pad slides. Since the structure is provided with the vibration absorbing material, the high frequency vibration of the disk rotor can be attenuated at a high speed, and an excellent effect of suppressing brake squeal can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a bearing device according to an embodiment of the present invention.

FIG. 2 is a cutaway perspective view of a main part of the disk rotor shown in FIG.

3A is a vibration waveform diagram of a brake pad, and FIG. 3B is a vibration waveform diagram of a disc rotor.

[Explanation of symbols]

1 Bearing device 2 hub wheels 3 Double row rolling bearing 4 drive shaft 5 disk rotor 7a, 7b Brake pad 20 Annular hollow part 21 oil

Claims (3)

[Claims] 1. A disc rotor for braking, the rotation of which is braked by pressure contact of a brake pad, wherein the disc rotor is generated inside an annular portion with which the brake pad slides in contact with the brake pad. A disc rotor for a brake, which is provided with a vibration absorbing material for absorbing and attenuating high frequency vibration peculiar thereto. 2. The brake disk rotor according to claim 1, wherein the annular portion is provided with an annular hollow portion that is continuous in the circumferential direction or a plurality of hollow portions that are distributed in several places on the circumference. A disc rotor for a brake, wherein heat resistant oil sealed in the hollow portion is used as the vibration absorbing material. 3. A bearing device in which a disk rotor whose rotation is braked by pressure contact of brake pads on both sides in the axial direction is attached to a radially outward flange provided on a hub wheel, wherein the brake pad is slidably contacted. A bearing device, wherein a vibration absorbing material for absorbing and attenuating a high-frequency vibration peculiar to the disk rotor, which is generated due to pressure contact of the brake pad, is provided inside the annular portion.