JP2016121795A - Vehicular disk brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular disk brake having a simple structure capable of restricting brake noise and spacing apart a friction pad from a disk rotor when braking is released in well-condition.SOLUTION: An ear piece 6a of a friction pad 6 is formed into a stepped shape where an outside protruding length in a disk radial direction at an outside surface in a disk rotating direction becomes shorter than a protruding length of inside in a disk radial direction and a spacing part E1 is formed between the outside in a disk radial direction of the ear piece 6a and a pad guide groove 3c. The spacing E1 is arranged at a position where it passes through a center of gravity of the friction pad 6 and an imaginary line crossing at a right angle with a center line connecting the center of a disk rotor 2 with a center of a piston 7. A pad return spring 11 comprises an engaging part 11a, a spring part 11c formed by bending back an extended piece extending from the engaging part 11a to extend out to a counter disk rotor side through the curved part toward the disk rotor side and an abutting part 11d arranged at the extremity end of the spring part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle disc brake, and more specifically, a pair of ear pieces projecting on both sides of a back plate of a friction pad is supported by a pad guide groove formed on a caliper support arm of a caliper bracket so that the friction pad is mounted. The present invention relates to a vehicle disc brake supported so as to be movable in the disc axial direction.

  Conventionally, in a disc brake that supports a pair of ear pieces projecting on both sides of a back plate of a friction pad in a pad guide groove formed on a caliper support arm of a caliper bracket, between the ear piece and the caliper support arm, There was one in which a pad return spring for urging the friction pad toward the non-disk rotor side when braking was disposed.

  As this pad return spring, a retainer part arranged on the torque receiving surface of the pad guide groove and guiding the movement of the friction pad, and an extending piece extending from the retainer part are brought into contact with the ear piece through the curved part, Some have a pad return portion that urges the friction pad toward the side opposite to the disk rotor when braking is released. Further, as the pad return part, the elongated piece is bent back from the side opposite the disk rotor of the retainer part to the disk rotor side to form an elastic part, and the distal end side of the elongated piece is further extended toward the disk rotor, and the distal end part is Some of them are slanted and curved in the extending direction, and a space that allows the pad return part to operate is formed between the ear piece of the friction pad and the pad guide groove. (For example, refer to Patent Document 1).

Japanese Patent No. 5242842

  However, in the above-mentioned Patent Document 1, there is a concern that the structure of the pad return spring becomes complicated and the cost increases. Furthermore, the friction pad generates a force that sinks inward in the radial direction of the disk on the disk delivery side due to braking torque generated by sliding contact with the disk rotor during braking, and floats outward in the radial direction of the disk on the disk delivery side. Each of the force to be applied acts, and the ear piece on the disk delivery side is pressed against the inner peripheral surface of the pad guide groove, and the ear piece on the disk introduction side is pressed against the outer peripheral side surface of the pad guide groove. The ear piece is fixed in the pad guide groove, but the spring force of the pad return portion may prevent the ear piece from being fixed in the pad guide groove, and may cause a brake squeal.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle disc brake that has a simple structure and suppresses brake squealing and that can satisfactorily separate the friction pad from the disc rotor when the brake is released.

  In order to achieve the above object, a vehicle disc brake according to the present invention includes a caliper bracket fixed to a vehicle body, and a pair of caliper support arms that support the caliper body extending from the outer edge of the disc rotor to the disc axial direction. The caliper support arm is provided with a pad guide groove correspondingly, and ear pieces projecting from both side portions of the back side of the friction pad disposed with the disc rotor interposed therebetween are supported by the pad guide groove, In the disc brake for a vehicle in which a pad return spring is disposed between the piece and the caliper support arm to urge the friction pad toward the opposite disc rotor side when braking is released, the ear piece is a disc on the outer surface in the disc rotation direction. The protrusion length on the outer side in the radial direction is formed in a stepped shape that is shorter than the protrusion length on the inner side in the radial direction of the disk. A space portion is formed between the outer side and the pad guide groove, and the space portion passes through the center of gravity of the friction pad and is orthogonal to the center line connecting the center of the disk rotor and the center of the piston. It arrange | positions in the position through which the 1st virtual line to pass is characterized.

  Furthermore, it is preferable that the space portion is disposed at a position passing through the center of the piston and passing through a second imaginary line orthogonal to the center line. The pad return spring is formed by bending back a locking portion locked to the ear piece and an extending piece extending from the locking portion to the side opposite to the disk rotor toward the disk rotor side via a curved portion. It is preferable to include a formed spring portion and a contact portion provided at the tip of the spring portion and contacting the side of the caliper support arm opposite to the disk rotor. Furthermore, it is preferable that the locking portion is disposed at a position through which the first imaginary line passes.

  According to the vehicle disc brake of the present invention, the force that sinks inward in the radial direction of the disc on the disc delivery side of the friction pad due to the braking torque generated by the sliding contact between the friction pad and the disc rotor during braking, A space is formed between the ear piece on the disk delivery side and the pad guide groove when a force to float to the outside in the disk radial direction is applied on the entry side, and the space part is Since the imaginary line passing through the center of gravity of the friction pad and perpendicular to the center line connecting the center of the disk rotor and the center of the piston passes, the disk delivery side of the friction pad is directed inward in the disk radial direction. The sinking force is promoted, and the inner side in the disc radial direction of the ear piece on the disc delivery side is strongly pressed against the disc delivery side surface of the pad guide groove. Along with this, the outer side in the disk radial direction of the ear piece on the disk entry side is strongly pressed against the outer side surface in the disk radial direction of the pad guide groove, and the ear piece is fixed in the pad guide groove, thereby suppressing the occurrence of brake squeal. Can do.

  Further, the space portion is arranged at a position passing through the center of the piston and passing through the second imaginary line orthogonal to the center line, so that the disk delivery side of the friction pad is moved in the disk radial direction by the braking torque. The force that sinks inward is further promoted.

  Further, the pad return spring is formed by bending back a locking portion locked to the ear piece and an extending piece extending from the locking portion to the side opposite to the disk rotor toward the disk rotor side through the bending portion. The spring portion of the pad return spring is provided in the space portion as in the prior art by including a spring portion and an abutting portion provided at the tip of the spring portion and abutting against the side of the caliper support arm opposite to the disk rotor. Since the pad return spring has only a spring force that urges the friction pad toward the disk rotor side when braking is released, the ear piece is fixed in the pad guide groove during braking. There is no risk of interference. Furthermore, by disposing the locking portion of the pad return portion at a position where the first imaginary line passes, the friction pad is pulled back in the horizontal direction by the spring force of the pad return spring and released from the side surface of the disk rotor when braking is released. Therefore, uneven wear of the lining can be prevented.

It is a principal part sectional front view of the disc brake which shows one example of the present invention. It is a principal part sectional rear view similarly. It is a principal part sectional top view of a disk brake similarly. It is a partial cross section front view of a disk brake similarly. It is a partially broken rear view of the disc brake. It is a top view of a disk brake similarly. It is VII-VII sectional drawing of FIG. It is a perspective view of the friction pad which shows one form of this invention.

  FIG. 1 to FIG. 8 are views showing one embodiment of a vehicle disc brake according to the present invention. An arrow A indicates a rotation direction of a disc rotor that rotates integrally with a wheel when the vehicle moves forward. The disk entry side is assumed to be when the vehicle is moving forward.

  The disc brake 1 according to this embodiment includes a disc rotor 2 that rotates integrally with a wheel, a caliper bracket 3 that is fixed to a vehicle body at one side of the disc rotor 2, and caliper support arms 3a and 3a of the caliper bracket 3. Further, a caliper body 5 supported so as to be movable in the disk axial direction via a pair of slide pins 4 and 4 is opposed to the inside of the action part 5a and reaction part 5b of the caliper body 5 with the disk rotor 2 interposed therebetween. It consists of a pair of friction pads 6 and 6 arranged.

  The caliper body 5 is composed of the above-described action part 5a and reaction part 5b arranged on both sides of the disk rotor 2, and a bridge part 5c that connects these parts across the outer edge of the disk rotor 2, and the action part 5a Are provided with a cylinder hole 5d opened on the disk rotor 2 side and a reaction force claw 5e on the reaction portion 5b. The cylinder hole 5d accommodates a bottomed cylindrical piston 7. The piston 7 moves the cylinder hole 5d in the direction of the disk rotor by the hydraulic pressure supplied to the hydraulic chamber 8 defined on the cylinder hole bottom side. It is supposed to move. Further, vehicle body mounting arms 5f and 5f are projected from the side of the action portion 5a, and the above-mentioned slide pins 4 are projected from mounting bolts 9 at the tips of the vehicle body mounting arms 5f. ing.

  The caliper support arms 3a and 3a span the outer edge of the disc rotor 2 in the disc axial direction while sandwiching both sides of the bridge portion 5c from both sides of the caliper bracket 3, and further, on the other side of the disc rotor 2, the reaction portion 5b. The shape extends along the side wall of the disc toward the center of the disc.

  Each caliper support arm 3a is provided with a guide hole 3b for accommodating the slide pin 4 described above, and the four caliper support arms 3a and 3a are respectively opposed to each other at the respective sides of the disc rotor 2. A pad guide groove 3c is provided. Each pad guide groove 3c is formed in a U-shape having a disk radial direction outer side surface 3d, a disk radial direction inner side surface 3e, and an opposing surface 3f connecting both side surfaces 3d, 3e. The ear pieces 6a of the friction pad 6 are inserted through the retainer 10, respectively.

  Each friction pad 6 has ear pieces 6a, 6a projecting from both sides of the back plate 6b, and a lining 6c attached to one side surface of the back plate 6b. The ear piece 6a is formed in a stepped shape in which both the disk rotation direction end faces 6d and 6d have a protruding length on the outer side in the disk radial direction shorter than a protruding length on the inner side in the disk radial direction. On the outer side in the disk radial direction of the other side surface of each ear piece 6a, an engaging convex portion 6e formed by cutting out a part of the cylindrical convex portion in the axial direction is formed, and a pad return spring is formed on the engaging convex portion 6e. 11 are respectively attached.

  The pad retainer 10 is attached to the pad guide grooves 3c, 3c on both sides of the disk rotor on the disk insertion side or the disk extraction side, and a pair of retainer portions 10a, 10a for guiding the movement of the ear piece 6a in the disk axial direction. A connecting piece 10b that connects the pair of retainer portions 10a and 10a across the outer edge of the disk rotor 2 is provided. The inner piece 10d of each retainer portion 10a is formed to be inclined outward in the disk rotor radial direction, and is biased outward in the disk radial direction of the ear piece 6a to prevent the friction pads 6 and 6 from rattling.

  The pad return spring 11 is formed by bending a band-shaped metal plate, and is attached to the ear piece 6a from the end of the engaging portion 11a on the side opposite to the disc rotor to the side opposite to the disc rotor. A spring part 11c formed by bending the extended piece back to the disk rotor side via the curved part 11b, and provided at the tip of the spring part 11c, is provided on the side of the anti-disk rotor 3g of the caliper support arm 3a. The engaging portion 11a is formed with an insertion hole 11e having the same shape as the cross-sectional shape of the engaging convex portion 6e, and the abutting portion 11d is convex on the caliper bracket side. It is formed in an arc shape.

  The pad return spring 11 formed in this way is assembled to the ear piece in a state of being prevented from rotating by inserting the insertion hole 11e into the engagement convex part 6e of the ear piece 6a and caulking the engagement convex part 6e. It is done. The friction pad 6 with the pad return spring 11 attached to each ear piece 6a inserts the ear pieces 6a, 6a from the opposite disk rotor side into the pad guide grooves 3c, 3c with the pad retainer 10 attached thereto, The abutting portion 11d is assembled in contact with the anti-disc rotor side surface 3g of the caliper support arm 3a, and a space E1 is formed between the outer side of the ear piece 6a in the disc radial direction and the pad guide groove 3c.

  Further, as shown in FIG. 5, the space E1 passes through the center of gravity G1 of the friction pad 6 and is orthogonal to a center line CL1 that connects the center of the disk rotor 2 and the center P1 of the piston 7. It arrange | positions in the position where line VL1 passes, and is arrange | positioned in the position where the 2nd virtual line VL2 which passes through the center P1 of piston 7 and is orthogonal to center line CL1 passes. Moreover, the latching | locking part 11a of the pad return spring 11 is arrange | positioned in the position where the 1st virtual line VL1 passes.

  In the disc brake 1 formed as described above, when the pressurized hydraulic fluid is supplied to the hydraulic pressure chamber 8 by the driver's braking operation, the piston moves forward through the cylinder hole 5d, and the friction on the action portion 5a side The pad 6 is pressed against one side of the disk rotor 2. Next, the reaction force causes the caliper body 5 to move toward the action part while being guided by the slide pins 4, 4, and the reaction force claw 5 e presses the friction pad 6 on the reaction part side against the other side of the disk rotor 2. To do.

  At this time, when the friction pad 6 is applied with a braking torque, a force that sinks inward in the radial direction of the disk on the disk delivery side and a force that floats outward in the radial direction of the disk on the disk delivery side are applied. A space E1 is formed between the piece 6a and the pad guide groove 3c, and the space E1 is disposed at a position through which the first virtual line VL1 and the second virtual line VL2 pass. Thus, the force that the disk delivery side of the friction pad 6 sinks inward in the disk radial direction is promoted, and the inner side of the disk radial direction of the ear piece 6a on the disk delivery side resists the resilience of the inner piece 10d of the retainer portion 10a. Then, the pad guide groove 3c is strongly pressed against the inner surface 3e in the disk radial direction. Accordingly, the outer side in the disk radial direction of the ear piece 6a on the disk entry side is strongly pressed against the outer side surface 3d in the disk radial direction of the pad guide groove 3c, and the ear piece 6a is fixed in the pad guide groove 3c. Occurrence can be suppressed. At this time, the pad return spring 11 is deformed in a direction in which the spring portion 11 c is separated from the ear piece 6 a as the friction pad 6 is pressed against the side surface of the disk rotor 2.

  On the other hand, when the above-described braking is released and the piston 7 and the reaction force claw 5e retreat to the position at the start of braking, the spring portion 11c of the pad return spring 11 attempts to return to the initial shape, and thus the locking portion 11a. Then, the ear pieces 6 a, 6 a are pressed against the disk rotor side to forcibly separate the friction pads 6 from the side surfaces of the disk rotor 2. Thereby, dragging of each friction pad 6 can be prevented.

  In the present embodiment, as described above, the ear piece 6a of the friction pad 6 is reliably fixed to the pad guide groove 3c during braking, so that brake noise can be suppressed. Further, unlike the prior art, the spring portion of the pad return spring is not disposed in the space E1 formed between the ear piece 6a and the pad guide groove 3c. Since it has only a spring force that urges the friction pad 6 to the side opposite to the disk rotor when the brake is released, there is no possibility of preventing the ear piece 6a from being fixed in the pad guide groove when the pad return spring 11 is braked. . Further, since the engaging portion 11a of the pad return spring 11 is disposed at a position where the first imaginary line VL1 passes, the friction pad 6 is pulled back in the horizontal direction by the spring force of the pad return spring 11 when the brake is released. The disc rotor 2 can be separated from the side surface, and uneven wear of the dining room 6c can be prevented.

  Note that the disc brake of the present invention is not limited to the above-described embodiment, and the structure of the engaging portion of the pad return spring is arbitrary, and the engaging portion is formed in a U-shape and the ear piece is sandwiched therebetween. It may be a combination. Furthermore, in this embodiment, the center of gravity of the friction pad is located on the inner side in the disk radial direction than the center of the piston, but the center of the piston and the center of gravity of the friction pad may overlap. Furthermore, as long as the friction pad is provided with an ear piece, other shapes are arbitrary, and the shape of the caliper body is also arbitrary.

DESCRIPTION OF SYMBOLS 1 ... Disc brake, 2 ... Disc rotor, 3 ... Caliper bracket, 3a ... Caliper support arm, 3b ... Guide hole, 3c ... Pad guide groove, 3d ... Disc radial direction outer surface, 3e ... Disc radial direction inner surface, 3f ... Opposite surface, 3g ... anti-disk rotor side surface, 4 ... slide pin, 5 ... caliper body, 5a ... action part, 5b ... reaction part, 5c ... bridge part, 5d ... cylinder hole, 5e ... reaction force claw, 5f ... body attachment Arm, 6 ... friction pad, 6a ... ear piece, 6b ... back plate, 6c ... lining, 6d ... disk rotation direction both ends, 6e ... engagement convex part, 7 ... piston, 8 ... hydraulic chamber, 9 ... mounting bolt DESCRIPTION OF SYMBOLS 10 ... Pad retainer, 10a ... Retainer part, 10b ... Connection piece, 10c ... Inner piece, 11 ... Pad return spring, 11a ... Locking part, 11b ... Curved part, 11c ... Spring part 11d ... contact portion, 11e ... insertion hole

Claims (4)

A caliper bracket fixed to the vehicle body spans the outer edge of the disc rotor in the disc axial direction, and a pair of caliper support arms that support the caliper body is extended, and a pad guide groove is provided corresponding to the caliper support arm, Ear pieces projecting from both sides of the back side of the friction pad disposed with the disc rotor interposed therebetween are supported by the pad guide groove, and the friction between the ear pieces and the caliper support arms is released when braking is released. In a vehicle disc brake having a pad return spring that urges the pad to the side opposite to the disc rotor,
The ear piece is formed in a stepped shape in which a protrusion length on the outer side in the disk radial direction of the disk rotation direction is shorter than a protrusion length on the inner side in the disk radial direction. A space is formed between the first groove and the guide groove. The space passes through the center of gravity of the friction pad and is perpendicular to a center line connecting the center of the disk rotor and the center of the piston. A disc brake for a vehicle, which is disposed at a position where a line passes.   2. The vehicle disc brake according to claim 1, wherein the space portion is disposed at a position passing through a center of the piston and passing through a second imaginary line orthogonal to the center line.   The pad return spring is formed by bending a locking portion locked to the ear piece and an extending piece extending from the locking portion to the side opposite to the disc rotor toward the disc rotor side via a curved portion. 3. The vehicle disc brake according to claim 1, further comprising: a spring portion; and a contact portion that is provided at a tip of the spring portion and contacts a side surface of the caliper support arm opposite to the disc rotor.   The vehicular disc brake according to claim 3, wherein the locking portion is disposed at a position where the first imaginary line passes.

Images