JP2011163484A - Disc brake device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disc brake device which prevents earth and sand from invading into a disc rotor and easily discharge invading earth and sand without damaging a heat radiation of the disc rotor. <P>SOLUTION: A disc brake device 22 is equipped with: a disc rotor 19 fixed in a hub 13 of wheel 2; and caliper and dust cover 25 attached to a knuckle 3 rotatably supporting the wheel 2, and covers the disc rotor 19 from vehicle width direction inner side by the dust cover 25. The dust cover 25 is arranged in the inner space S of the disc rotor 19. An invasion preventing wall, which extends from an attaching section of the knuckle 3 to radially outer side and is adjacently arranged in the inner circumferential surface of the disc of the disc rotor 19, is formed in the dust cover 25, and a plurality of ellipse-like openings are formed in the invasion preventing wall. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a disc brake device provided with a dust cover disposed on the inner side in the vehicle width direction of a disc rotor.

  A disc brake device as a braking device for a vehicle presses a disc rotor fixed to a wheel hub by a brake pad of a caliper attached to a vehicle body side, and applies braking to the rotation of the wheel by a frictional resistance generated therebetween. Is.

  In such a disc brake device, the friction surfaces of these disc rotors and brake pads are covered with a dust cover and shielded from the outside so that water, earth and sand do not adhere to the friction surfaces of the disc rotor and brake pads. It has been broken. This dust cover prevents water and earth and sand from entering the disc rotor and lowering the braking force due to adhesion to the disc rotor, and also prevents scattering of wear powder such as disc rotors and brake pads around the disc rotor. The disc rotor is attached so as to cover almost the entire surface except the portion where the caliper is disposed from the inner side in the vehicle width direction.

  However, if the disk rotor is covered with a dust cover, there arises a problem that the heat dissipation of the disk rotor that generates heat due to friction with the brake pad is deteriorated.

  Therefore, for example, Patent Documents 1 and 2 propose a configuration for improving the cool air property of the disk rotor. That is, in Patent Document 1, an air intake is formed in the dust cover, and a wind collecting wall for collecting air flowing around the dust cover at the air intake is provided on the outer surface of the dust cover. A configuration has been proposed in which a side wall is formed on the side surface to guide the air taken in from the air inlet to the inlet of the air flow passage of the disk rotor.

  In Patent Document 2, in a disc brake device having a ventilated disc (ventilated disc), an air intake hole for taking in outside air is provided in the dust cover, and the air vent is adjacent to the inlet of the disc from the periphery of the air vent. There has been proposed a structure in which an annular air guide flange extending in an integrated manner is provided.

Japanese Patent Laid-Open No. 55-115635 Japanese Utility Model Publication No. 60-020842

  However, as proposed in Patent Documents 1 and 2, when an opening such as an air intake or a sampling hole is formed in the dust cover, there is a problem that earth and sand easily enter the disk rotor from the opening.

  In addition, once dirt or the like enters the disk rotor from the opening of the dust cover, the intruded earth or sand cannot be easily discharged, and there is a possibility that the earth and sand may accumulate in the disk rotor. There is a possibility that pebbles and the like are caught between the disc rotor and the dust cover and generate abnormal noise.

  The present invention has been made in view of the above problems, and its intended process is to prevent the intrusion of earth and sand into the disk rotor without impairing the heat dissipation of the disk rotor, and the intruded earth and sand. DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a disc brake device that can easily discharge the gas.

  In order to achieve the above object, the invention according to claim 1 includes a disk rotor fixed to a hub of a wheel, a caliper attached to a knuckle that rotatably supports the wheel, and a dust cover. In the disc brake device that covers the disc rotor from the inner side in the vehicle width direction, the dust cover is arranged in an internal space of the disc rotor.

  According to a second aspect of the present invention, in the first aspect of the present invention, the dust cover is disposed close to the inner peripheral surface of the disk of the disk rotor by extending radially outward from the attachment portion to the knuckle. An intrusion prevention wall is formed, and a plurality of oval openings are formed in the intrusion prevention wall.

  According to a third aspect of the present invention, in the second aspect of the present invention, a discharge portion extending downward is formed on the intrusion prevention wall of the dust cover, and a clearance in the vehicle width direction between the discharge portion and the disk surface of the disk rotor is formed. Is set to be larger than the width dimension of the opening formed in the intrusion prevention wall and the radial gap between the outer peripheral surface of the dust cover and the inner peripheral surface of the disk of the disk rotor.

  According to the first aspect of the present invention, since the dust cover is arranged in the inner space of the disk rotor, the dust cover having a small size can effectively prevent intrusion of earth and sand into the disk rotor, and the dust cover However, the heat dissipation from the disk rotor is not obstructed, and the temperature rise of the disk rotor can be suppressed to prevent the braking force from being lowered.

  According to the second aspect of the present invention, since the plurality of oval openings are formed in the intrusion prevention wall provided in the dust cover, the external cooling air is prevented while preventing the intrusion of earth and sand into the internal space of the disk rotor. Can be introduced into the internal space of the disk rotor through a plurality of openings to cool the disk rotor, and a reduction in braking force due to a temperature increase of the disk rotor can be prevented.

  According to the third aspect of the present invention, the sand or the like that has entered the disk rotor can be discharged by the discharge portion formed on the intrusion prevention wall of the dust cover. If the discharge part is arranged between the disk rotor and the surrounding parts arranged in the vicinity of the disk rotor, heat transfer (thermal influence) from the disk rotor to the surrounding parts can be cut off, and it is particularly vulnerable to heat. Thermal adverse effects on rubber products can be avoided. Further, the vehicle width direction clearance between the discharge portion and the disk surface of the disk rotor is determined by the width dimension of the opening formed in the intrusion prevention wall and the radial clearance between the outer peripheral surface of the dust cover and the inner peripheral surface of the disk rotor. Therefore, it is possible to reliably discharge the earth and sand that has entered the inner space of the disc rotor to the outside through the gap, and prevent sedimentation and abnormal noise in the inner space of the disc rotor. be able to.

It is a fracture rear view of the front suspension part of a vehicle provided with the disc brake device concerning the present invention. FIG. 2 is an enlarged detail view of a main part of FIG. 1. 1 is an exploded perspective view of a disc brake device according to the present invention. It is an internal view of the disc rotor in which the dust cover of the disc brake device according to the present invention is incorporated. It is the A section enlarged detail drawing of FIG. It is a figure of the arrow B direction of FIG. FIG. 5 is a longitudinal sectional view of the dust cover of the disc brake device according to the present invention (a sectional view taken along the line CC of FIG. 4).

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 is a rear rear view of a front suspension portion of a vehicle equipped with a disc brake device according to the present invention, FIG. 2 is an enlarged detail view of a main part of FIG. 1, FIG. 3 is an exploded perspective view of the disc brake device, and FIG. FIG. 5 is an enlarged detail view of part A in FIG. 4, FIG. 6 is a view in the direction of arrow B in FIG. 4, and FIG. 7 is a longitudinal sectional view of the dust cover. It is the CC sectional view taken on the line of FIG.

  The front suspension 1 shown in FIG. 1 is a strut type, and a knuckle 3 that rotatably supports a front wheel 2 that is a steered wheel and a suspension arm 4 that is arranged in the vehicle width direction and a shock absorber that is arranged substantially in the vertical direction. 5 is supported by the vehicle body so as to be movable up and down. Since the basic configuration of the pair of left and right front suspensions 1 is the same, only one (left side) will be illustrated and described below.

  One end of the suspension arm 4 on the inner side in the vehicle width direction is rotatably supported on the vehicle body by a shaft 6, and the outer side in the vehicle width direction is formed integrally with the lower part of the knuckle 3 via a ball joint 7. It is connected to the stay 3a. The upper end of the shock absorber 5 is attached to the vehicle body by a nut 9 via a mount rubber 8, and the lower end is attached to a stay 3 b formed integrally with the upper portion of the knuckle 3 by two upper and lower bolts 10. ing. In FIG. 1, 11 is a tie rod, and 12 is a drive shaft.

  A hub 13 is rotatably supported on the knuckle 3 via a bearing 14, and a spindle 15 is inserted through the center of the hub 13. The hub 13 is fastened to the spindle 15 by tightening a nut 16 that is screwed onto the end of the spindle 15, and the wheel 2 a of the front wheel 2 is connected to a plurality of bolts 17 on the flange 13 a of the hub 13. It is attached by a nut 18 that is screwed into the nut.

  By the way, a substantially disc-shaped disk rotor 19 is fixed to the flange 13a of the hub 13 by a plurality of screws 20. When the wheel 2a of the front wheel 2 is attached to the hub 13, a plurality of bolts 17 together with the wheel 2a. And a nut 18 screwed into the hub 13 (flange 13a). A disc brake device 22 according to the present invention is constituted by the disc rotor 19 and a later-described caliper 21 (see FIG. 3) for clamping the rotation of the front wheel 2 by clamping the disc rotor 19 with hydraulic pressure.

  The disc brake device 22 according to the present embodiment is a ventilated type with improved heat dissipation, and on the outer periphery of a cylindrical portion 19a projecting at the center of the disc rotor 19, there are two ring-shaped inner and outer discs 19A ( A disc at the center of the vehicle) and 19B (discs at the outside of the vehicle) are arranged at a predetermined interval. As shown in FIG. 2, ventilating fins 19b along the radial direction for connecting and supporting the two disks 19A and 19B are provided with an appropriate interval in the circumferential direction between the two disks 19A and 19B. A plurality of air passages 23 are formed between the two disks 19A and 19B so as to penetrate from the inner diameter portion to the outer diameter portion of the disk 19A between the adjacent ventilation fins 19b in the circumferential direction. Yes.

  A caliper 21 shown in FIG. 3 is attached to stays 3 c and 3 d formed integrally with the knuckle 3 by bolts 24. The caliper 21 includes brake pads (not shown) disposed on both sides of the disks 19A and 19B of the disk rotor 19, and when a master cylinder (not shown) is driven by a depression operation of a brake pedal (not shown) by a driver. The hydraulic pressure generated in the master cylinder is transmitted to the caliper 21 through a brake pipe (not shown) to operate the brake pad, and the brake pad presses the disks 19A and 19B of the disk rotor 19 to sandwich them from both sides. For this purpose, braking is applied to the rotation of the front wheels 8, whereby the vehicle is decelerated or stopped.

  Thus, in order to prevent intrusion of water, gravel and the like into the internal space S of the disc rotor 19, the internal space S of the disc rotor 19 is covered from the inner side in the vehicle width direction by the sheet metal dust cover 25. The embodiment is characterized in that the dust cover 25 is disposed in the internal space S of the disk rotor 19.

  Here, as shown in FIGS. 4 and 7, the dust cover 25 is formed with a cylindrical press-fit fixing portion 25 a at the center, and the press-fit fixing portion 25 a is formed as shown in FIGS. 1 and 2. The dust cover 25 is attached to the knuckle 3 by press-fitting into the outer periphery of the boss 3 </ b> A of the knuckle 3. As shown in FIGS. 1 and 2, when the dust cover 25 is attached to the knuckle 3, the press-fit fixing portion 25 a is disposed in the internal space S of the disk rotor 19. The press-fit fixing portion 25a of the dust cover 25 is formed in a substantially U-shaped cross section as shown in FIG. 7, thereby stabilizing the press-fit fastening force of the dust cover 25 and improving the insertion workability. ing.

  As shown in FIGS. 4 and 7, the dust cover 25 extends from the center press-fit fixing portion 25a (attachment portion to the knuckle 3) while inclining radially inward in the vehicle width direction. A substantially ring-shaped intrusion prevention wall 25A is formed around the entire press-fit fixing portion 25a. The intrusion prevention wall 25A is for preventing water and gravel from entering the internal space S of the disc rotor 19, and the outer peripheral edge of the intrusion prevention wall 25A is the disc 19A (the disc on the vehicle center side). It is located within the inner diameter and close to the inner diameter surface. In the intrusion prevention wall 25A, a plurality of oblong openings 26 that are elongated in the radial direction through which the cooling air can pass are formed at appropriate intervals in the circumferential direction.

  In addition, a substantially rectangular discharge portion 25B extending substantially vertically downward continuously from the lower end of the intrusion prevention wall 25A is integrally formed at the lower portion of the dust cover 25. As shown in FIGS. 1 and 2, when the dust cover 25 is attached to the knuckle 3 by press-fitting, the intrusion prevention wall 25A of the dust cover 25 is accommodated in the internal space S of the disk rotor 19, and its outer periphery is the disk. Although located close to the inner peripheral surface of 19A, the lower end of the intrusion prevention wall 25A, in which the discharge portion 25B is integrally formed, protrudes inward of the vehicle from the disk 19A. A discharge portion 25B extending substantially vertically downward from the lower part of the intrusion prevention wall 25A of the dust cover 25 is located between the disk 19A and the ball joint 7 along the friction sliding surface of the disk 19A of the disk rotor 19, The disk rotor 19 is spaced from the surface (friction sliding surface) of the disk 19A by a predetermined distance, and a predetermined vehicle width direction clearance c (see FIG. 5) is formed between the discharge portion 25B and the surface of the disk 19A of the disk rotor 19. 6) is formed.

  Here, a clearance c in the vehicle width direction between the discharge portion 25B of the dust cover 25 and the surface (disk surface) of the disk 19A of the disk rotor 19 is the width dimension a of the front opening 26 formed in the intrusion prevention wall 25A and the dust. It is set larger than the radial gap b (see FIG. 5) between the outer peripheral surface of the cover 25 and the inner peripheral surface of the disk 19A of the disk rotor 19 (c> a, b).

  Thus, in the disc brake device 22 configured as described above, when the disc rotor 19 rotates together with the front wheels 2 while the vehicle is running, the disc brake device 22 is attracted by the negative pressure generated in the internal space S of the disc rotor 19. External cooling air flows into the internal space S of the disk rotor 19 from a plurality of openings 26 formed in the intrusion prevention wall 25A of the dust cover 25, and this cooling air is generated by the plurality of ventilation fins 19b of the disk rotor 19. The air is sucked into the plurality of air passages 23 by the fan effect. Then, the cooling air sucked into the air passages 23 of the disk rotor 19 flows radially outward through the air passages 23 by the centrifugal force accompanying the rotation of the disk rotor 19, and the disk rotor 19 is forcibly cooled in the process. To do.

  Thus, since the disk rotor 19 can expose the frictional sliding surface of the disk 19A in addition to the forced cooling by the cooling air, it is cooled by natural heat dissipation and the temperature rise is suppressed. A reduction in braking force generated by the brake device 22 is prevented. The plurality of openings 26 formed in the intrusion prevention wall 25 </ b> A of the dust cover 25 prevent external sand from entering the internal space S of the disk rotor 19 and allows external cooling air to flow into the internal space S of the disk rotor 19. It fulfills the function to be introduced.

  In the disc brake device 22 according to the present invention, since the dust cover 25 is disposed in the internal space S of the disc rotor 19, the dust cover 25 having a small size can effectively prevent intrusion of earth and sand into the disc rotor 19. In addition, since the dust cover 25 does not hinder the heat radiation from the disk rotor 19, the temperature rise of the disk rotor 19 is suppressed, and the braking force is prevented from being lowered.

  Further, in the present embodiment, since the discharge portion 25B formed on the dust cover 25 is located between the disk 19A of the disk rotor 19 and the ball joint 7, the discharge portion 25B is transferred from the disk rotor 19 to the ball joint 7. It functions as a heat shield that blocks heat transfer. For this reason, the thermal adverse effect on the rubber boot 27 covering the ball joint 7 can be avoided, and the durability of the heat-sensitive boot 27 can be enhanced.

  In the present embodiment, as described above, the gap c in the vehicle width direction between the discharge portion 25B of the dust cover 25 and the surface (disk surface) of the disk 19A of the disk rotor 19 is the length formed in the intrusion prevention wall 25A. Since the width dimension a of the circular opening 26 and the radial gap b (see FIG. 5) between the outer peripheral surface of the dust cover 25 and the inner peripheral surface of the disk 19A of the disk rotor 19 are set (c> a, b ), The sand and the like that has entered the internal space S of the disc rotor 19 can be reliably discharged to the outside through the gap, and the accumulation of soil and the like in the internal space S of the disc rotor 19 and the generation of abnormal noise can be prevented. Can be prevented. In particular, in the present embodiment, the discharge part 25B of the dust cover 25 is formed substantially vertically along the surface (friction sliding surface) of the disk 19A of the disk rotor 19 at the lower part of the dust cover 25. The distance (gap c) between the disk rotor 19 and the surface (friction sliding surface) of the disk 19A is the width a of the opening 26 and the radial gap between the dust cover 25 and the inner peripheral surface of the disk 19A of the disk rotor 19. Even if it is larger than b, there is almost no possibility that soil or the like from the gap enters.

DESCRIPTION OF SYMBOLS 1 Front suspension 2 Front wheel 2a Front wheel 3 Knuckle 3A Knuckle boss 3a-3d Knuckle stay 4 Suspension arm 5 Shock absorber 6 Shaft 7 Ball joint 8 Mount rubber 9 Nut 10 Bolt 11 Tie rod 12 Drive shaft 13 Hub 13a Flange 14 Bearing 15 Spindle 16 Nut 17 Bolt 18 Nut 19 Disc rotor 19A, 19B Disc rotor disc 19a Disc rotor cylindrical portion 19b Disc rotor vent fin 20 Screw 21 Caliper 22 Disc brake device 23 Air passage 24 Bolt 25 Dust cover 25A Dust cover intrusion prevention wall 25B Dust cover discharge part 25a Dust cover press-fit fixing part 26 Cover opening 27 Ball joint boot a Width of dust cover opening b Radial clearance between the outer peripheral surface of the dust cover and the inner peripheral surface of the disc c Clearance in the vehicle width direction between the discharge portion of the dust cover and the disc rotor S Disc Rotor internal space

Claims (3)

In a disc brake device comprising: a disc rotor fixed to a wheel hub; a caliper attached to a knuckle that rotatably supports the wheel; and a dust cover, wherein the disc rotor is covered from the inner side in the vehicle width direction by the dust cover. ,
A disc brake device, wherein the dust cover is disposed in an internal space of the disc rotor.   An intrusion prevention wall is formed in the dust cover so as to extend radially outward from an attachment portion to the knuckle and is disposed close to an inner peripheral surface of the disk of the disk rotor, and the intrusion prevention wall has a plurality of lengths. 2. The disc brake device according to claim 1, wherein a circular opening is formed. A discharge portion extending downward is formed on the intrusion prevention wall of the dust cover, and a gap in the vehicle width direction between the discharge portion and the disk surface of the disk rotor is formed in the width dimension of the opening and the dust formed in the intrusion prevention wall. 3. The disc brake device according to claim 2, wherein the disc brake device is set larger than a radial clearance between an outer peripheral surface of the cover and an inner peripheral surface of the disc of the disc rotor.

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