Vehicle disc brakes and friction pads

Abstract

This disc brake and friction pad for a vehicle prevent displacement of a pad spring during assembly, thereby improving the assembly characteristics. A pad spring 6 comprises: a hanger pin abutment section 6a that abuts the outer circumferential surface of a hanger pin 4 on the inside in the radial direction of a disc; a first resilient part 6c and second resilient part 6e that abut a pair of friction pads 5, 5 and bias the friction pads 5, 5 toward the inside in the radial direction of the disc; and a first positioning piece 6g and second positioning piece 6h that abut the friction pads 5, 5 and position the pad spring 6 when the friction pads 5, 5 and the pad spring 6 are assembled on a caliper body 3.

Description

Technical Field

[0005]

[0001] The present invention relates to a disc brake for a vehicle, and more particularly to a disc brake for a vehicle and a friction pad that suppress play of a friction pad suspended by a hanger pin with a pad spring.

Background Art

[0002] Conventionally, as a vehicle disc brake that suppresses play of a friction pad suspended by a hanger pin with a pad spring, a hanger pin is provided in a ceiling opening formed in a bridge portion of a caliper body, disposed in the disk axial direction across the outer periphery of the disk rotor, and suspends a pair of friction pads so as to be movable in the disk rotor axial direction. A pad spring is disposed between the hanger pin and the friction pad, and the friction pad is urged inward in the disk radius direction by an elastic piece of the pad spring to suppress play of the friction pad (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the vehicle disc brake of Patent Document 1 described above, when assembling the friction pad and the pad spring, a pair of friction pads are disposed in a friction pad housing portion, the pad spring is disposed outside the friction pad in the disk radius direction, and then the hanger pin is inserted through the friction pad to assemble the friction pad to the caliper body. At the same time, the pad spring is assembled between the hanger pin and the friction pad, and the elastic piece of the pad spring is brought into contact with the friction pad.

[0005] However, when inserting the hanger pin into the friction pad and assembling the pad spring between the hanger pin and the friction pad, the pad spring sometimes shifted, making it impossible to assemble the pad spring in the correct position.

[0006] Therefore, the present invention aims to provide a vehicle disc brake and friction pad that can prevent the position of the pad spring from shifting during assembly and improve the ease of assembly of the pad spring. [Means for solving the problem]

[0007] To achieve the above objective, the present invention provides a vehicle disc brake comprising: a caliper body having an operating portion disposed on the side of a disc rotor and having a cylinder hole for inserting a piston, and a bridge portion disposed across the outer circumference of the disc rotor; a pair of friction pads disposed on both sides of the disc rotor; a hanger pin disposed across the outer circumference of the disc rotor in the disc axial direction and suspending the pair of friction pads so as to be movable in the axial direction of the disc rotor; and a pad spring disposed between the hanger pin and the friction pads and biasing the friction pads at least inward in the disc radial direction, wherein the pad spring comprises a hanger pin contact portion that abuts the outer circumferential surface of the hanger pin on the disc radially inward side, an elastic portion that abuts the pair of friction pads and biases the friction pads inward in the disc radial direction, and a positioning piece that abuts the friction pads when assembling the friction pads and the pad spring to the caliper body to position the pad spring.

[0008] Furthermore, the caliper body has a friction pad housing portion for housing the friction pad, and a locking groove for locking the pad spring is formed on the disc entry side wall of the friction pad housing portion when the vehicle is moving forward. The pad spring comprises a first spring portion that contacts the disc entry side of the friction pad when the vehicle is moving forward and biases the friction pad at least inward in the disc radial direction, and a second spring portion that contacts the disc exit side of the friction pad when the vehicle is moving forward and biases the friction pad inward in the disc radial direction and towards the disc exit side. The first spring portion is provided with the positioning piece and a locking piece that is inserted into the locking groove, and it is preferable that the locking groove is formed radially outward from the housing groove of the disc rotor.

[0009] Furthermore, the bridge portion has a ceiling opening in the middle of the circumferential direction of the disc, the first resilient portion is formed to be wide in the axial direction of the disc, and is provided with a first restraining portion that abuts against the wall of the ceiling opening to restrain the behavior of the pad spring, and the contact surface of the wall that the first restraining portion abuts against is preferably a cast surface.

[0010] Furthermore, the second resilient portion is formed to be wide in the disc axial direction and is provided with a second restraining portion that abuts against the wall of the ceiling opening to restrain the behavior of the pad spring, and it is preferable that the contact surface of the wall that the second restraining portion abuts against is a cast surface.

[0011] Furthermore, the friction pad used in a vehicle disc brake has a lining attached to a backing plate, wherein the backing plate is provided with a suspension piece having a pin insertion hole in the middle of its longitudinal direction, and a pad spring contact portion is provided in parallel with the suspension piece, to which a positioning piece of a pad spring provided in the vehicle disc brake abuts when the friction pad is assembled to the vehicle disc brake.

[0012] Furthermore, it is preferable to provide a recess between the pad spring contact portion and the suspension piece, which serves as a space capable of accommodating the positioning piece. [Effects of the Invention]

[0013] According to the present invention, when assembling the friction pad and pad spring to the caliper body, the positioning piece formed on the pad spring is brought into contact with the friction pad, thereby eliminating the risk of the pad spring shifting and improving the ease of assembling the pad spring.

[0014] Furthermore, a locking groove for securing the pad spring is formed on the disc entry side wall of the friction pad housing when the vehicle is moving forward. The pad spring comprises a first spring portion that contacts the disc entry side of the friction pad when the vehicle is moving forward, biasing the friction pad inward in the radial direction of the disc, and a second spring portion that contacts the disc exit side of the friction pad, biasing the friction pad inward in the radial direction of the disc. The first spring portion is provided with a locking piece that is inserted into the locking groove. The locking groove is formed radially outward from the housing groove of the disc rotor. As a result, if an attempt is made to assemble the pad spring with the disc exit side and disc entry side reversed, the set load will increase significantly, making assembly impossible and thus preventing incorrect assembly of the pad spring.

[0015] Furthermore, the bridge section has a ceiling opening in the middle of the circumferential direction of the disc, and a first restraining part is provided on the first spring portion of the pad spring that contacts the wall of the ceiling opening to restrain the behavior of the pad spring, thereby suppressing the unruly movement of the pad spring due to running vibrations. In addition, since the contact surface of the wall to which the first restraining part contacts is a cast surface, processing costs can be reduced.

[0016] Furthermore, by providing a second restraining part in the second spring section that contacts the wall of the ceiling opening to restrain the behavior of the pad spring, it is possible to suppress the unruly movement of the pad spring due to running vibrations. In addition, since the contact surface of the wall that the second restraining part contacts is a cast surface, it is possible to reduce processing costs.

[0017] Furthermore, it is a friction pad used for a vehicle disk brake with a lining attached to the back plate. The back plate includes a hanging piece having a pin insertion hole at the longitudinal middle part, and when assembling the friction pad to the vehicle disk brake, a pad spring contact part where a positioning piece of a pad spring provided on the vehicle disk brake abuts is provided in parallel with the hanging piece, so that the positioning of the pad spring can be achieved with the friction pad. Also, a concave part serving as a space part capable of accommodating the positioning piece is provided between the pad spring contact part and the hanging piece, so that the positioning piece can be easily accommodated and the weight of the friction pad can be reduced.

Brief Description of the Drawings

[0018] [Figure 1] It is a front view of a vehicle disk brake showing an exemplary form of the present invention. [Figure 2] It is also a rear view of the vehicle disk brake. [Figure 3] It is also a plan view of the vehicle disk brake. [Figure 4] It is also a side view of the vehicle disk brake. [Figure 5] It is a cross-sectional view taken along the line V-V of FIG. 4. [Figure 6] It is a cross-sectional view taken along the line VI-VI of FIG. 1. [Figure 7] It is a cross-sectional view taken along the line VII-VII of FIG. 1. [Figure 8] It is an explanatory view when assembling the friction pad and the pad spring to the caliper body. [Figure 9] It is a perspective view of the pad spring.

Embodiments for Carrying Out the Invention

[0019] FIGS. 1 to 9 are diagrams showing an exemplary form of the vehicle disk brake and the friction pad of the present invention. Arrow A indicates the rotational direction of the disk rotor that rotates integrally with the wheel when the vehicle moves forward. The disk outgoing side and the disk incoming side described below refer to those when the vehicle moves forward.

[0020] The vehicle disk brake 1 includes a disk rotor 2 that rotates integrally with a wheel (not shown) in the direction of arrow A, a caliper body 3 attached to the vehicle body on one side of the disk rotor 2, and a pair of friction pads 5, 5 disposed opposite to each other across the disk rotor 2 inside the caliper body 3 and suspended by hanger pins 4. A pad spring 6 for suppressing the play of the friction pads 5, 5 abuts against the friction pads 5, 5.

[0021] The caliper body 3 is a radial mount type split caliper body, which is divided by a bridge portion 3a straddling the outer peripheral side of the disk rotor 2, and is formed by integrally connecting an anti-vehicle body side caliper half body 21 and a vehicle body side caliper half body 31 with two connecting bolts 7, 7. Further, a rectangular ceiling opening 3b having wall portions 3c, 3c parallel to the disk rotor 2 and wall portions 3d, 3d parallel to the disk axis is formed at the central portion in the disk circumferential direction of the bridge portion 3a.

[0022] The anti-vehicle body side caliper half body 21 has an acting portion 21b in which cylinder portions 21a, 21a each having a cylinder hole 22 for inserting a piston 8 are arranged side by side in the disk circumferential direction, and a bridge portion half body 21c constituting approximately half of the bridge portion 3a. Similarly, the vehicle body side caliper half body 31 also has an acting portion 31b in which cylinder portions 31a, 31a each having a cylinder hole 32 for inserting a piston 8 are arranged side by side in the disk circumferential direction, and a bridge portion half body 31c constituting approximately half of the bridge portion 3a. Further, an anti-vehicle body side ceiling opening 21d and a vehicle body side ceiling opening 31d constituting approximately half of the ceiling opening 3b are respectively formed in the bridge portion half bodies 21c, 31c.

[0023] The caliper half 21 on the opposite side of the vehicle body has hydraulic chambers 23, 23 defined between the bottom of the cylinder bores 22, 22 and the pistons 8, 8 into which working fluid is introduced. Furthermore, a first working fluid introduction hole 24 is drilled from the disc exit side of the dividing surface 21e, which is the joint surface of the bridge half 21c, toward the hydraulic chamber 23 on the disc exit side. A part of the bottom of the cylinder bore 22 on the disc exit side has a first contouring section 25a that connects the hydraulic chamber 23 on the disc exit side and the first working fluid introduction hole 24 by contouring, and a second contouring section 25b that contours toward the hydraulic chamber 23 on the disc entry side. Furthermore, a third contouring section 25c is formed in a part of the bottom of the cylinder hole 22 on the disc entry side, and contouring is performed toward the second contouring section 25b. By connecting the second contouring section 25b and the third contouring section 25c, the first working fluid introduction hole 24, the hydraulic chamber 23 on the disc exit side, and the hydraulic chamber 23 on the disc entry side are connected.

[0024] Furthermore, the disc ejection side of the bridge section half 21c is provided with a union hole 26 that opens to the disc ejection side surface 21f of the bridge section half 21c and the first working fluid introduction hole 24. The union hole 26 has a female threaded portion 26a formed on the opening side for screwing in a union bolt (not shown). In addition, radial mount type vehicle mounting portions 27, 27 are formed on the disc insertion side and disc ejection side of the caliper half 21 opposite the vehicle body. Mounting bolt insertion holes 27a, 27a in the radial direction of the disc are formed in the vehicle mounting portions 27, 27, and the caliper body 3 is attached to the vehicle body by screwing mounting bolts inserted through these mounting bolt insertion holes 27a, 27a into the caliper mounting portions provided on the vehicle body side. Furthermore, large diameter flange portions 27b, 27b for reinforcement are formed at the outer end and inner end in the radial direction of the disc, respectively, of each vehicle mounting portion 27.

[0025] Furthermore, the working portion 21b of the caliper half 21 on the side opposite the vehicle body comprises cylinder portions 21a, 21a having cylinder holes 22, 22, a discharge-side body portion 21g extending from the cylinder portion 21a on the disc discharge side to the disc discharge side, and a re-entry-side body portion 21j extending from the cylinder portion 21a on the disc re-entry side to the disc re-entry side. A pair of first reinforcing ribs 28, 28 are provided on the outer and inner sides in the disc radial direction of the disc on the side surface 21h opposite the disc rotor of the discharge-side body portion 21g. The first reinforcing rib 28 on the outer side in the disc radial direction connects the cylinder portion 21a on the disc discharge side to the large-diameter flange portion 27b on the outer side in the disc radial direction of the vehicle body mounting portion 27 on the disc discharge side. The first reinforcing rib 28 on the inner side in the disc radial direction connects the cylinder portion 21a on the disc discharge side to the large-diameter flange portion 27b on the inner side in the disc radial direction of the vehicle body mounting portion 27 on the disc discharge side. Furthermore, a first weight-reducing portion 21i, which is a thin-walled portion, is formed by casting on the side surface 21h of the disc rotor between the first reinforcing ribs 28, 28.

[0026] Furthermore, a pair of second reinforcing ribs 29, 29 are provided on the outer and inner sides in the radial direction of the disc on the side surface 21h opposite the disc rotor of the entry-side body portion 21j. The second reinforcing rib 29 on the outer side in the radial direction of the disc connects the cylinder portion 21a on the entry-side of the disc to the large-diameter flange portion 27b on the outer side in the radial direction of the disc of the vehicle body mounting portion 27 on the entry-side of the disc. The second reinforcing rib 29 on the inner side in the radial direction of the disc connects the cylinder portion 21a on the entry-side of the disc to the large-diameter flange portion 27b on the inner side in the radial direction of the disc of the vehicle body mounting portion 27 on the entry-side of the disc. In addition, a second weight-reducing portion 21k, which is a thin-walled portion, is formed by casting on the side surface 21h opposite the disc rotor between the second reinforcing ribs 29, 29.

[0027] Furthermore, as shown in Figures 1 and 6, the outer surface (opposite the disc rotor side) OS1 of each first reinforcing rib 28 is formed to gradually incline toward the disc rotor side toward the disc rotation side, compared to the outer surface OS2 (opposite the disc rotor side) of the cylinder portion 21a. Similarly, the outer surface (opposite the disc rotor side) OS3 of each second reinforcing rib 29 is also formed to gradually incline toward the disc rotor side toward the disc entry side, compared to the outer surface OS2 (opposite the disc rotor side) of the cylinder portion 21a.

[0028] Furthermore, a mounting boss portion 30 is formed at the center of the circumferential direction of the disk on the radially outer surface of the working portion 21b, and is equipped with a pin insertion hole 30a through which the hanger pin 4 is inserted.

[0029] The caliper half 31 on the vehicle body side has hydraulic chambers 33, 33 defined between the bottom of the cylinder bores 32, 32 and the pistons 8, 8 into which working fluid is introduced. A second working fluid inlet hole 34 is drilled from the disc exit side of the dividing surface 31e, which is the joint surface of the bridge half 31c, toward the hydraulic chamber 33 on the disc exit side, and the first working fluid inlet hole 24 and the second working fluid inlet hole 34 are in communication at the dividing surfaces 21e, 31e. A part of the bottom of the cylinder bore 32 on the disc exit side has a fourth contouring section 35a that connects the hydraulic chamber 33 on the disc exit side and the second working fluid inlet hole 34 by contouring, and a fifth contouring section 35b that contours toward the hydraulic chamber 33 on the disc entry side. Furthermore, a sixth contouring section 35c is formed in a part of the bottom of the cylinder hole 32 on the disc entry side, and contouring is performed toward the fifth contouring section 35b. By connecting the fifth contouring section 35b and the sixth contouring section 35c, the second working fluid introduction hole 34, the hydraulic chamber 33 on the disc exit side, and the hydraulic chamber 33 on the disc entry side are connected.

[0030] Furthermore, the disc discharge side of the bridge portion half 31c is provided with a bleeder portion 37 having a bleeder hole 36 that opens to the radially outer surface 31f of the disc and to the second working fluid introduction hole 34.

[0031] The bleeder hole 36 has a female threaded portion 36a formed on the opening side into which the bleeder screw 39 is screwed. The bleeder screw 39 has an air discharge hole (not shown) on its inner circumference and a male threaded portion 39a on its outer circumference that screws into the female threaded portion 36a. A rubber bleeder cap 40 is attached to the tip of the screw.

[0032] Furthermore, the working portion 31b of the caliper half 31 on the vehicle body side comprises cylinder portions 31a, 31a having cylinder holes 32, 32, a discharge-side body portion 31g extending from the cylinder portion 31a on the disc discharge side to the disc discharge side, and a re-entry-side body portion 31j extending from the cylinder portion 31a on the disc re-entry side to the disc re-entry side. A pair of third reinforcing ribs 41, 41 are provided on the outer and inner sides in the disc radial direction of the disc radial side of the side surface 31h of the discharge-side body portion 31g opposite the disc rotor. The third reinforcing rib 41 on the outer side in the disc radial direction connects the cylinder portion 31a on the disc discharge side to the disc discharge-side end of the discharge-side body portion 31g. The third reinforcing rib 41 on the inner side in the disc radial direction connects the cylinder portion 31a on the disc discharge side to the disc discharge side of the third reinforcing rib 41 on the outer side in the disc radial direction. Furthermore, a third weight-reducing portion 31i, which is a thin-walled portion, is formed by casting on the side surface 31h opposite the disc rotor between the third reinforcing ribs 41, 41.

[0033] Furthermore, a pair of fourth reinforcing ribs 42, 42 are provided on the outer and inner sides in the radial direction of the disc on the side surface 31h opposite the disc rotor of the entry-side body portion 31j. The fourth reinforcing rib 42 on the outer side in the radial direction of the disc connects the cylinder portion 31a on the disc entry side and the disc entry-side end of the entry-side body portion 31j. The fourth reinforcing rib 42 on the inner side in the radial direction of the disc connects the cylinder portion 31a on the disc entry side and the disc rotor entry side of the fourth reinforcing rib 42 on the outer side in the radial direction of the disc. In addition, a fourth weight-reducing portion 31k, which is a thin-walled portion, is formed by casting on the side surface 31h opposite the disc rotor between the fourth reinforcing ribs 42, 42.

[0034] Furthermore, as shown in Figures 2 and 6, the outer surface (opposite the disc rotor side) OS4 of each third reinforcing rib 41 is formed to be gradually inclined toward the disc rotor side toward the disc rotation side, compared to the outer surface OS5 (opposite the disc rotor side) of the cylinder portion 31a. Similarly, the outer surface (opposite the disc rotor side) OS6 of each fourth reinforcing rib 42 is also formed to be gradually inclined toward the disc rotor side toward the disc entry side, compared to the outer surface OS5 (opposite the disc rotor side) of the cylinder portion 31a.

[0035] Furthermore, a mounting boss portion 43 is formed on the outer surface of the working portion 31b in the circumferential direction of the disc, with a pin insertion hole 43a for inserting a hanger pin 4, facing the mounting boss portion 30 of the caliper half 21 on the side opposite the vehicle body.

[0036] The caliper body 3 is formed by joining the anti-vehicle-side caliper half 21 and the vehicle-side caliper half 31, which are formed in this manner, at the bridge portion 3a, with the divided surfaces 21e, 31e abutting against each other, and connecting them with connecting bolts 7, 7. Furthermore, by connecting the anti-vehicle-side caliper half 21 and the vehicle-side caliper half 31, the first hydraulic fluid inlet hole 24 and the second hydraulic fluid inlet hole 34 are connected, and consequently, the first hydraulic fluid inlet hole 24, the second hydraulic fluid inlet hole 34, and the hydraulic pressure chambers 23 of the anti-vehicle-side caliper half 21 and the hydraulic pressure chambers 33 of the vehicle-side caliper half 31 are connected, forming a hydraulic passage L1. In addition, since the union hole 26 is connected to the first hydraulic fluid inlet hole 24, hydraulic fluid is supplied to the hydraulic passage L1 via the union hole 26. Furthermore, since the bleeder hole 36 is in communication with the second working fluid inlet hole 34, air mixed in with the working fluid introduced into the fluid passage L1 is discharged to the outside via the bleeder screw 39.

[0037] Furthermore, friction pad housing sections 9 for housing the friction pads 5 are formed in the discharge-side body sections 21g, 31g and the re-entry-side body sections 21j, 31j. The disc discharge-side wall 9a of the friction pad housing section 9 formed in the discharge-side body sections 21g, 31g and the disc re-entry-side wall 9b of the friction pad housing section 9 formed in the re-entry-side body sections 21j, 31j are torque receiving sections that contact the friction pads 5, 5 and receive torque during braking. In addition, a locking groove 9c for locking the pad spring 6 is formed in the disc re-entry-side wall 9b.

[0038] Each friction pad 5 consists of a lining 5a that slides against the side surface of the disc rotor 2 and a metal backing plate 5b to which the lining 5a is attached. The backing plate 5b has a hanging piece 5e protruding from the center of the outer surface 5c in the radial direction of the disc (the longitudinal middle part of the backing plate 5b), which has a hanger pin insertion hole 5d through which a hanger pin 4 is inserted. Adjacent to the disc rotation side and disc entry side of the hanging piece 5e, a pair of first pad spring contact portions 5f, 5f (pad spring contact portions of the present invention) are provided, which the pad spring 6 contacts. Furthermore, a pair of second pad spring contact portions 5g, 5g are provided protruding from the disc exit side end and the disc entry side end of the radially outer surface 5c of the disc, and the suspension piece 5e, the first pad spring contact portions 5f, 5f, and the second pad spring contact portions 5g, 5g are respectively provided in parallel in the circumferential direction of the disc on the radially outer surface 5c of the disc.

[0039] The hanger pins 4 are inserted through the pin insertion holes 30a and 43a of the mounting bosses 30 and 43, respectively, and are mounted in the disc axial direction through the ceiling opening 3b of the caliper body 3. They are also inserted through the hanger pin insertion holes 5d and 5d of the suspension pieces 5e and 5e provided on the friction pads 5, suspending the friction pads 5, 5 so that they can move in the disc axial direction while housed in the friction pad housing 9. In addition, a pad spring 6 is provided across the back plate 5b and the hanger pins 4, pressing the friction pads 5, 5 inward in the disc radial direction and on the disc rotation side.

[0040] The pad spring 6 is formed by bending a single sheet of material that has been punched into a predetermined shape, and includes an arc-shaped hanger pin contact portion 6a that abuts against the outer peripheral surface of the hanger pin 4 on the inner side in the radial direction of the disc, a first resilient portion 6c that extends from the hanger pin contact portion 6a via a strip-shaped first spring piece 6b towards the disc entry side and abuts against the first pad spring contact portion 5f on the disc entry side of the friction pads 5, 5, and a second resilient portion 6e that extends from the hanger pin contact portion 6a via a strip-shaped second spring piece 6d towards the disc exit side and abuts against the second pad spring contact portion 5g on the disc exit side of the friction pads 5, 5.

[0041] The first spring portion 6c includes a first spring piece 6f that contacts the first pad spring contact portion 5f on the disc rotation side of the friction pad 5, causing the friction pads 5, 5 to spring inward in the radial direction of the disc and outward from the disc rotor, first positioning pieces 6g, 6g and second positioning pieces 6h, 6h that contact the friction pads 5, 5 and pad spring 6 when assembling the friction pads 5, 5 and pad spring 6 to the caliper body 3 to position the pad spring 6, and a locking piece 6i that is locked into the locking groove 9c.

[0042] The first positioning pieces 6g,6g and the second positioning pieces 6h,6h are formed by cutting and bending a portion of the first resilient piece 6f in an arc shape in the radial direction of the disc. As shown in Figure 8, when assembling the friction pads 5,5 and the pad spring 6 to the caliper body 3, the first positioning pieces 6g,6g are inserted into the recesses 5h,5h (spaces) formed between the suspension pieces 5e,5e and the first pad spring contact portions 5f,5f on the disc entry side. That is, the first positioning pieces 6g,6g are housed in the recesses 5h,5h, with their tips contacting the disc entry sides 5i,5i of the first pad spring contact portions 5f,5f, while the second positioning pieces 6h,6h contact the outer surface 5c in the radial direction of the disc of the backing plate 5b near the second pad spring contact portions 5g,5g on the disc entry side.

[0043] Furthermore, the locking piece 6i protrudes toward the disk rotation side from the central part of the disk rotation side end of the first spring piece 6f, and its tip 6j is inserted into the locking groove 9c. In addition, the first spring piece 6f is formed to be wide in the disk rotation direction, and its end faces 6k, 6k (first restraining parts of the present invention) on the side opposite the disk rotor abut against the wall portions 3c, 3c of the ceiling opening 3b, respectively.

[0044] The second spring portion 6e is formed by bending the disc rotation side outward in an arc shape in the radial direction of the disc, and the bent portion 6m is brought into contact with the disc rotation side surfaces 5j, 5j of the second pad spring contact portions 5g, 5g on the disc rotation side. Furthermore, the second spring portion 6e is formed to be wide in the disc axial direction, and the end faces 6n, 6n (second restraint portion of the present invention) on the side opposite the disc rotor are in contact with the wall portions 3c, 3c of the ceiling opening 3b. The wall portions 3c, 3c on the side opposite the disc rotor of the ceiling opening 3b, which the end faces 6k, 6k, 6n, 6n are in contact with, are each formed with a cast surface. In addition, the outer surface 9d in the radial direction of the disc of the locking groove 9c is formed further outward in the radial direction of the disc than the accommodating groove 3e of the disc rotor 2 formed on the disc rotor side surface of the bridge portion 3a.

[0045] The assembly of the friction pads 5,5 and pad spring 6 formed in this manner to the caliper body 3 is as follows: First, as shown in Figure 8, the friction pads 5,5 are placed in the friction pad housing 9, and the pad spring 6 is placed on the radially outer side of the friction pads 5,5 in the disc direction, and the tip 6j of the locking piece 6i is locked into the locking groove 9c.

[0046] At this time, the first positioning pieces 6g, 6g are inserted into the recesses 5h, 5h formed between the suspension pieces 5e, 5e and the first pad spring contact portions 5f, 5f on the disc entry side, with their tips in contact with the disc entry sides 5i, 5i of the first pad spring contact portions 5f, 5f, and the second positioning pieces 6h, 6h are in contact with the radially outer surfaces 5c, 5c of the disc near the second pad spring contact portions 5g, 5g on the disc entry side, so that the pad spring 6 is positioned relative to the friction pads 5, 5.

[0047] Next, the hanger pin 4 is inserted through the pin insertion hole 30a of the mounting boss portion 30 of the caliper half 21 on the side opposite the vehicle body, the 43a of the mounting boss portion 43 of the caliper half 31 on the vehicle body, and the hanger pin insertion holes 5d, 5d of the suspension pieces 5e, 5e provided on the friction pads 5, 5, thereby suspending the friction pads 5, 5 so that they can move in the disc axial direction. Furthermore, the outer peripheral surface of the hanger pin 4 on the inner side in the disc radial direction and the hanger pin contact portion 6a of the pad spring 6 come into contact and press against the pad spring 6, thereby positioning the pad spring 6 in the correct position as shown in Figure 5.

[0048] The pad spring 6, positioned in the correct location, contacts the outer peripheral surface of the hanger pin 4 on the inner side in the disc radial direction with the hanger pin contact portion 6a of the pad spring 6, and the tip portion 6j of the locking piece 6i is locked into the locking groove 9c. The first spring piece 6f of the first spring portion 6c contacts the outer surfaces 5k, 5k in the disc radial direction of the first pad spring contact portions 5f, 5f on the disc entry side of the friction pads 5, 5. Since the outer surfaces 5k, 5k in the disc radial direction are formed to gradually incline toward the disc rotor side from the disc exit side toward the disc entry side, the first pad spring contact portions 5f, 5f spring the friction pads 5, 5 inward in the disc radial direction and toward the disc exit side. The second spring-launching section 6e has a bent section 6m that contacts the disc-returning side surfaces 5j, 5j of the second pad spring contact sections 5g, 5g on the disc-returning side of the friction pads 5, 5, causing the friction pads 5, 5 to spring inward in the disc radial direction and towards the disc-returning side. Furthermore, the end faces 6k, 6k, 6n, 6n contact the wall sections 3c, 3c on the side of the ceiling opening 3b opposite the disc rotor.

[0049] In this embodiment, the caliper body 3 is provided with a first positioning piece 6g and a second positioning piece 6h on the pad spring 6 as described above. When assembling the friction pads 5, 5 and the pad spring 6 to the caliper body 3, the first positioning piece 6g and the second positioning piece 6h are brought into contact with the friction pads 5, 5, thereby positioning the pad spring 6 relative to the friction pads 5, 5 and improving the ease of assembling the pad spring 6.

[0050] Furthermore, a locking groove 9c for securing the pad spring 6 is formed in the disc entry side wall 9b of the friction pad housing 9, and the outer surface 9d in the disc radial direction of the locking groove 9c is formed further outward in the disc radial direction than the housing groove 3e of the disc rotor 2. Therefore, if an attempt is made to assemble the pad spring 6 with the disc exit side and disc entry side reversed, the set load will increase significantly, making assembly impossible and thus preventing incorrect assembly of the pad spring 6.

[0051] Furthermore, the pad spring 6 can suppress vibrations caused by the running of the pad spring by having the end faces 6k,6k of the first spring piece 6f and the end faces 6n,6n of the second spring piece 6e abut against the wall portions 3c,3c of the ceiling opening 3b on the side opposite the disc rotor. In addition, the contact surfaces of the wall portions 3c,3c that the end faces 6k,6k,6n,6n abut against are cast surfaces, which helps to reduce processing costs. Moreover, since the end faces 6k,6k,6n,6n and the bent portion 6m, including the first positioning piece 6g and the second positioning piece 6h, are formed in an arc shape, an effective contact area can be obtained.

[0052] Furthermore, the friction pad 5 has a suspension piece 5e projecting outward in the radial direction of the disc, a first pad spring contact portion 5f, and a second pad spring contact portion 5g arranged in parallel in the circumferential direction of the disc on the outer surface 5c of the backing plate 5b in the radial direction of the disc, and a recess 5h (space) into which the first positioning piece 6g can be inserted is provided between the suspension piece 5e and the first pad spring contact portion 5f, thereby enabling the first positioning piece 6g to make good contact with the backing plate 5b.

[0053] Furthermore, the present invention is not limited to being applied to a split-type caliper body as in the above-described embodiment, but can also be applied to a monocoque-type caliper body. In addition, the number of pistons and the configuration of the fluid passages are arbitrary. Moreover, the vehicle mounting portion formed on the caliper half opposite the vehicle body may be an axial-mount type vehicle mounting portion equipped with mounting bolt insertion holes in the disc axial direction. Furthermore, the present invention is not limited to being applied to a piston-opposed type disc brake caliper body as in the above embodiment, but can also be applied to a pin-slide type disc brake caliper body in which an action portion equipped with pistons and a reaction portion equipped with reaction claws are provided on both sides of the disc rotor. [Explanation of Symbols]

[0054] 1...Vehicle disc brake, 2...Disc rotor, 3...Caliper body, 3a...Bridge section, 3b...Ceiling opening, 3c,3d...Wall section, 3e...Housing groove, 4...Hanger pin, 5...Friction pad, 5a...Lining, 5b...Backing plate, 5c...Disc radial outer surface, 5d...Hanger pin insertion hole, 5e...Suspension piece, 5f...First pad spring contact section, 5g...Second pad spring contact section, 5h...Recess, 5i...Disc rotation side, 5j...Disc entry side, 5k...Disc radial outer surface, 6...Pad spring, 6a...Hanger pin contact section, 6b...First spring piece, 6c...First spring section, 6d...Second spring piece, 6e...Second spring section, 6f...First spring piece, 6g...First positioning piece, 6h...Second positioning piece, 6i...Locking piece, 6j...Tip section, 6m...Bent section, 6k,6n...end face, 7...connecting bolt, 8...piston, 9...friction pad housing, 9a...disc rotation side wall, 9b...disc entry side wall, 9c...locking groove, 21...caliper half opposite the vehicle body, 21a...cylinder part, 21b...acting part, 21c...bridge half, 21d...ceiling opening half, 21e...dividing surface, 21f...disc rotation side, 21g...return side body, 21h...side of the disc rotor opposite, 21i... 1st weight-reducing section, 21j...re-entry side body section, 21k...2nd weight-reducing section, 21m...disk radial outer surface, 22...cylinder hole, 23...hydraulic chamber, 24...1st working fluid inlet hole, 25a...1st contouring section, 25b...2nd contouring section, 25c...3rd contouring section, 26...union hole, 26a...female thread section, 27...vehicle body mounting section, 27a...mounting bolt insertion hole, 28...1st reinforcing rib, 29...Second reinforcing rib, 30...Mounting boss section, 30a...Pin insertion hole, 31...Vehicle side caliper half, 31a...Cylinder section, 31b...Operating section, 31c...Bridge section half, 31d...Ceiling opening half, 31e...Dividing surface, 31f...Disc radial outer surface, 31g...Returning side body section, 31h...Anti-disc rotor side, 31i...Third weight-reducing section, 31j...Returning side body section, 31k...Fourth weight-reducing section, 32... 33...Cylinder bore, 34...Hydraulic chamber, 35a...Second working fluid inlet, 35a...Fourth contouring section, 35b...Fifth contouring section, 35c...Sixth contouring section, 36...Bleeder hole, 36a...Female thread section, 37...Bleeder section, 39...Bleeder screw, 39a...Male thread section, 40...Bleeder cap, 41...Third reinforcing rib, 42...Fourth reinforcing rib, 43...Mounting boss section, 43a...Pin insertion hole,

Claims

1. A caliper body having an operating portion positioned on the side of the disc rotor and having a cylinder hole into which a piston is inserted, and a bridge portion positioned across the outer circumference of the disc rotor, A pair of friction pads are arranged on both sides of the disc rotor, A hanger pin is provided which spans the outer circumference of the disc rotor and is arranged in the disc axial direction, and which suspends a pair of friction pads so as to be movable in the axial direction of the disc rotor, A pad spring is disposed between the hanger pin and the friction pad, and biases the friction pad at least inward in the radial direction of the disc. In a vehicle disc brake equipped with, The pad spring has a hanger pin contact portion that contacts the outer peripheral surface of the hanger pin on the inner side in the radial direction of the disc, A resilient portion that contacts the pair of friction pads and biases the friction pads inward in the radial direction of the disc, When assembling the friction pad and the pad spring to the caliper body, a positioning piece is provided that contacts the friction pad to position the pad spring, Equipped with, The caliper body has a friction pad housing portion for housing the friction pad, and a locking groove for locking the pad spring is formed on the disc entry side wall of the friction pad housing portion when the vehicle is moving forward. The pad spring comprises a first spring that contacts the disc entry side of the friction pad when the vehicle is moving forward, biasing the friction pad at least inward in the disc radial direction, and a second spring that contacts the disc exit side of the friction pad when the vehicle is moving forward, biasing the friction pad inward in the disc radial direction and towards the disc exit side. The first spring portion is provided with the positioning piece and the locking piece that is inserted into the locking groove, The locking groove is formed radially outward from the housing groove of the disc rotor, characterized in that it is a disc brake for a vehicle.

2. The bridge section has a ceiling opening in the middle of the circumferential direction of the disk, The vehicle disc brake according to claim 1, characterized in that the first resilient portion is formed to be wide in the disc axial direction, and is provided with a first restraining portion that abuts against the wall of the ceiling opening to restrain the behavior of the pad spring, and the contact surface of the wall that the first restraining portion abuts against is cast.

3. The vehicle disc brake according to claim 2, characterized in that the second resilient portion is formed to be wide in the disc axial direction and is provided with a second restraining portion that abuts against the wall of the ceiling opening to restrain the behavior of the pad spring, and the contact surface of the wall that the second restraining portion abuts against is cast.

4. A friction pad used in vehicle disc brakes, with a lining attached to the backing plate, The backing plate is provided with a suspension piece having a pin insertion hole in the middle of its longitudinal direction, and a pad spring contact portion is provided in parallel with the suspension piece, which contacts a positioning piece of a pad spring provided on the vehicle disc brake when the friction pad is assembled to the vehicle disc brake. A friction pad characterized by having a recess between the pad spring contact portion and the suspension piece, which serves as a space capable of accommodating the positioning piece.

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