JP2004183904A - Disk brake for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pad spring of one-sheet structure favorable for assemblability, productivity and cost performance by ensuring a predetermined set load required for a friction pad. <P>SOLUTION: Pad-pressing pieces 16a and 16b of crank-shaped section to press an outer surface in the radial direction of a disk of friction pads 4 and 4 and a connection piece 16d continuous to the pad pressing pieces 16a and 16b are provided on a pad spring 16. Pin contact parts 16g and 16h to be brought into elastic contact with an inner side surface in the radial direction of the disk of a hanger pin 15 are provided on the connection piece 16d and centers of reinforcing pieces 16f and 16f. The pad pressing piece 16a is formed slightly longer than the width in the axial direction of the disk of a top opening part 14, and the pad pressing 16b is formed shorter than the width in the axial direction of the disk of the top opening part 14. The reaction force from the hanger pin 15 is given as a resilient force inward of the disk to the pad pressing pieces 16a and 16b from the connection piece 16d and the reinforcing pieces 16f and 16f. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a disc brake mounted on a traveling vehicle such as an automobile or a motorcycle, and more particularly to a disc brake of a type in which a friction pad is suspended using a hanger pin.

  In a vehicle disk brake of a type in which a pair of friction pads are hung on a caliper body using hanger pins, a plate-shaped pad spring is contracted outside the friction pad in a radial direction of the disk, and the friction pad is padded. A spring is urged inwardly of the disk so that the friction pad does not rattle due to running vibration or float out of the disk during braking (for example, see Patent Document 1).

In this disc brake, a hanger pin installed on a caliper body is inserted into a suspension piece of a friction pad, a pair of friction pads are arranged on both sides of a disc rotor to face each other, and a pair of pad holding pieces and both pads are attached to a pad spring. A connecting piece that connects the holding pieces is provided, and the center of the connecting piece arranged in the disk circumferential direction outside the disk rotor is elastically contacted with the inner surface of the hanger pin in the radial direction of the disk, and both pad holding pieces are friction pads. The friction pad is urged inward of the disk by making contact with the disk inflow side and the outflow side of the disk radially outer surface.
JP-A-5-180250

  In such a configuration, by setting a certain width to the connecting piece of the pad spring, the set load acting on the friction pad from the pad holding piece is retained, but the friction pads on both sides of the disk rotor are When the lining is fully worn out, the back plates of both friction pads are positioned so as to directly sandwich the disk rotor, and the pad springs Is sandwiched between the hanging pieces of the friction pads, so that the connecting piece cannot be made wider than the thickness of the disk rotor.

  For this reason, in the above-mentioned disc brake, a required set load necessary for suppressing the friction pad is secured by superposing and using two pad springs having substantially the same shape. This causes an increase in unsprung load, and is disadvantageous in terms of assemblability, productivity and cost.

  SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle disk brake in which a set load acting on a friction pad is sufficiently secured in a single-plate pad spring, and the above-mentioned problems are solved.

  According to the present invention, in accordance with the above-mentioned object, a ceiling opening through which a friction pad is inserted and removed is provided in a bridge portion of a caliper body disposed over the outside of a disk rotor so as to penetrate inside and outside, and the ceiling opening is formed by a disk shaft. A hanger pin, which penetrates the caliper body and penetrates in the direction, is inserted into a pad hanging piece of the friction pad, and a pair of friction pads are arranged to oppose each other on both sides of the disk rotor. In a vehicle disk brake for urging a disk inward with a pad spring having a structure, the pad spring includes a pad pressing piece that presses a radially outer surface of the pair of friction pads in the disk radial direction, and the pad pressing piece is continuous with the pad pressing piece. A connection is provided between the hanging pieces of the pair of friction pads in the circumferential direction of the disk and elastically contacts the inner surface of the hanger pin in the radial direction of the disk. Has the door, the pad pressing piece is characterized in that it is formed in a sectional shape of a crank while being longer than the disk axial direction of width of ceiling opening. According to this configuration, the reinforcing piece of the pad spring is disposed on the side of the friction pad opposite to the disk rotor, and does not hinder the friction pad that adjusts in the direction of the disk rotor as the lining wears. Therefore, the reinforcing piece can have a set load that is insufficient for the connecting piece whose lateral width is limited to the thickness of the disk rotor.

  The disc brake for a vehicle according to the present invention can reduce the unsprung load by weight reduction as compared with the conventional two-layered structure, and is excellent in productivity of pad springs and in ease of assembling to a caliper body, and at a low cost. Is also advantageous.

  An embodiment of the present invention will be described below with reference to FIGS. The disc brake 1 includes a disc rotor 2 that rotates integrally with a wheel (not shown) in the direction of arrow A, a four-pot opposed caliper body 3 fixed to the vehicle body at one side of the disc rotor 2, and a caliper body 3 And a pair of friction pads 4 and 4 which are arranged to face each other with the disk rotor 2 interposed between the action portions 3a and 3b.

  The caliper body 3 includes a pair of caliper halves 3 d and 3 e integrally formed with each of the action portions 3 a and 3 b, each of which has a half of a bridge portion 3 c disposed across the outside of the disk rotor 2. Cup-shaped pistons 9 are inserted into the four large and small cylinder holes 8 provided opposite to the action portions 3a, 3b in a liquid-tight manner. A hydraulic chamber 10 is defined between 9 and the bottom of the cylinder hole 8.

  The one working portion 3a on the vehicle body mounting side has a union hole 11 for introducing a hydraulic fluid into the hydraulic chamber 10 on the disc outlet side, and a bleeder screw 12 for discharging air mixed in the hydraulic fluid. Is provided. The two hydraulic chambers 10 and 10 of the action portion 3a communicate with each other through a liquid through hole (not shown), and two hydraulic chambers respectively opposed to the disk inlet side and the disk outlet side with the disk rotor 2 interposed therebetween. 10 and 10 communicate with each other through two liquid through holes 13 and 13 penetrating the bridge portion 3c.

  At the center of the bridge portion 3c, rectangular ceiling openings 14 are formed through the inside and outside of the disc rotor 2 so that the friction pads 4 can be inserted into and removed from both sides of the disc rotor 2. The action section side walls 3f, 3f of the ceiling opening 14 are recessed lower than the side walls on the disk entry and exit side, and separate guide grooves 3g, 3g are recessed on the disc entry side of the action section side walls 3f, 3f. In addition, bosses 3h and 3i for attaching hanger pins protruding from the outer surfaces of the operation portions 3a and 3b are provided substantially at the center of the outside of the operation portion side walls 3f and 3f. Extend to the same height.

  The upper and lower divided torque receiving portions 3j, 3j are flush with the disk entrance side and the exit side of the ceiling opening 14 on the disk entrance side and the exit side of the action portion 3a, 3b. Each friction pad 4 accommodates the main body 6a of the lining 5 and the back plate 6 between the torque receiving portions 3j, 3j, and the pin holes of the hanging pieces 6b located in the ceiling opening 14. 6c, the hanger pin 15 which penetrates through the ceiling opening 14 in the disk axis direction and extends over the bosses 3h, 3i is inserted, and is hung on the front surfaces of the pistons 9, 9 so as to be movable in the disk axis direction. Further, the disk is urged inwardly by a pad spring 16 engaged with the hanger pin 15.

  The union hole 11 is connected to a separate hydraulic master cylinder via a brake hose (both not shown), and the hydraulic fluid pressurized by the hydraulic master cylinder by a driver's brake operation is supplied to the union hole 11. To the four hydraulic chambers 10 to push each piston 9 toward the opening of the cylinder hole 8 and press the lining 5 of each friction pad 4 against the side surface of the disk rotor 2 to perform a braking action. It is.

  The pad spring 16 includes a pair of long and short parallel pad pressing pieces 16a and 16b formed in a crank shape in cross section, flat plate sections 16c and 16c continuous to the inside as a part of the pad pressing pieces 16a and 16b, and both flat sections. A connecting piece 16d connecting the centers of the connecting portions 16c, 16c, four cover portions 16e projecting from the flat plate portions 16c, 16c with the connecting piece 16d interposed therebetween, and a flat plate bypassing the outside of the facing cover portions 16e, 16e. Reinforcement pieces 16f, 16f projecting from the side ends of the portions 16c, 16c in a substantially trapezoidal shape.

  One pad pressing piece 16a is formed to be slightly longer than the width of the ceiling opening 14 in the disk axis direction, and the other pad pressing piece 16b is also formed to be slightly shorter than the width of the ceiling opening 14 in the disk axis direction. ing. The center connecting piece 16d is formed to have the same width as the thickness of the disk rotor 2 or a width slightly smaller than the thickness thereof. An arcuate pin contact portion 16g is recessed. An intermediate portion of the reinforcing pieces 16f, 16f parallel to the connecting piece 16d is located outside the pad holding pieces 16a, 16b and the flat plate portion 16c, and a pin contact of the connecting piece 16d is provided at the center of the intermediate portion. Pin contact portions 16h, 16h having the same shape as the portion 16g are recessed on the same straight line as the pin contact portion 16g of the connecting piece 16d.

  The pad spring 16 inserts the friction pads 4, 4 from the ceiling opening 14 into both sides of the disk rotor 2, and then removes the pad holding pieces 16 a, 16 b within the ceiling opening 14 to form the body portions of the back plates 6, 6. The two ends of one pad holding piece 16a on the disk entry side are accommodated in the guide grooves 3g, 3g of the bridge portion 3c by bridging the outer disk entry side end and the exit side end of 6a, 6a. Accordingly, the center connecting piece 16d is located along the outside of the disk rotor 2, the reinforcing pieces 16f on both sides are located outside the action portion side walls 3f, 3f of the ceiling opening 14, and the four connecting pieces 16d are located on the outside. A cover portion 16e is disposed so as to cover the outer sides of the friction pads 4 and 4 in the radial direction of the disk while sandwiching the hanging pieces 6b of the back plate 6.

  Next, while pressing the central portions of the connecting pieces 16d and the reinforcing pieces 16f, 16f inwardly of the disc, the hanger pins 15 are hung over the bosses 3h, 3i to suspend the friction pads 4, 4, and then the connecting pieces 16d. When the pressing of the reinforcing pieces 16d and the reinforcing pieces 16f, 16f is released, the pin contact portion 16g of the connecting piece 16d elastically contacts the inner surface of the hanger pin 15 in the radial direction of the disc outside the disc rotor 2, and the friction pads 4, 4 The pin contact portions 16h, 16h of the reinforcing pieces 16f, 16f bypassing the side opposite to the disk rotor, also elastically contact the inner surface of the hanger pin 15 in the disk radial direction. A reaction force from the hanger pin 15 acts on the connecting piece 16d and the reinforcing pieces 16f, 16f elastically contacting the hanger pin 15, and this reaction force is further applied to the outer disk reciprocating side end and the revolving side of the back plates 6, 6. The frictional pads 4 and 4 are transmitted to the pad holding pieces 16a and 16b applied to the ends as resilient force toward the inside of the disc, and the friction pads 4 and 4 are resiliently applied to the pad holding pieces 16a and 16b. It is urged toward.

  The resilient force acting on the pad holding pieces 16a, 16b is limited in the width within the plate thickness of the disk rotor 2 by the set load set on the center connecting piece 16d and also by the reinforcing pieces 16f, 16f on both sides. Since the insufficient set load acts on the connecting piece 16d, it is possible to effectively prevent the friction pads 4 and 4 from rattling and floating during braking. Further, since both reinforcing pieces 16f, 16f are disposed so as to bypass the friction pads 4, 4 on the side opposite to the disk rotor, the friction pads 4, 4 adjust in the disk rotor direction as the lining 5 wears. Even if the lining 5 is fully worn and both back plates 6 and 6 are positioned so as to directly sandwich the disk rotor 2, the connecting pieces 16d and the reinforcing pieces 16f and 16f of the pad spring 16 do not hinder braking. Absent.

  As described above, the pad spring 16 of the present embodiment can have a required set load necessary for suppressing the friction pads 4 and 4 in spite of having a single-plate structure, and can be compared with the conventional two-layer structure. Thus, the unsprung load can be reduced by reducing the weight, and the productivity of the pad spring 16 and the assemblability to the caliper body 3 are excellent, and the cost is also advantageous.

  Further, the four cover portions 16e provided on the pad spring 16 cover the outer sides of the friction pads 4 and 4 in the disk radial direction with the hanging pieces 6b of the back plate 6 interposed therebetween, so that water or The earth and sand are less likely to enter, and the operation failure of the disc brake 1 due to the adhesion of earth and sand and rust can be effectively suppressed, and the durability can be improved.

1 is a partial cross-sectional plan view of a disc brake showing one embodiment of the present invention. II-II sectional view of FIG. III-III sectional view of FIG. FIG. 2 is a perspective view of a pad spring showing one embodiment of the present invention.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 ... Disc brake, 2 ... Disc rotor, 3 ... 4-pot facing caliper body, 3a, 3b ... Working part, 3c ... Bridge part, 3f ... Working part side wall of ceiling opening 14, 3h, 3i ... Hanger pin attachment Boss portion, 3j torque receiving portion, 4 friction pad, 5 lining, 6 back plate, 6a body portion of back plate 6, 6b hanging piece of back plate 6, 6c pin hole, 14 ... ceiling opening, 15 ... hanger pin, 16 ... pad spring, 16a, 16b ... pad holding piece, 16d ... connecting piece, 16e ... cover part, 16f ... reinforcing piece, 16g, 16h ... pin contact part

Claims (1)

A bridge opening of a caliper body disposed over the outside of the disk rotor is provided with a ceiling opening through which friction pads are inserted and removed through the inside and outside, and the ceiling opening penetrates in the disk axial direction and is mounted on the caliper body. The hanger pin is inserted into the pad hanging piece of the friction pad, and a pair of friction pads are arranged on both sides of the disc rotor so as to face each other. In the vehicle disc brake for urging, the pad spring includes a pad pressing piece that presses a radially outer surface of the pair of friction pads in a disk radial direction, and a suspension of the pair of friction pads continuously to the pad pressing piece. A connection piece disposed between the pieces in the circumferential direction of the disc and elastically contacting the inner surface of the hanger pin in the disc radial direction. Vehicle disc brake, characterized in that it is formed in a sectional shape of a crank while being longer than the disk axial direction of width of ceiling opening.

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