JPH08270692A - Disc brake for vehicle - Google Patents

Abstract

PURPOSE: To effectively prevent the occurrence of deviated wear of a lining as mounting and demounting of a friction pad are simply effected through the ceiling opening of a bridge part. CONSTITUTION: The shim plate body 22a of a shim plate 22 comprises six upper and lower engaging claws 22b protruded in the direction of a piston; and four pad return pieces 22c protruded in the direction of a friction pad. The engaging claws 22b are locked in the hole of a piston. The two pad return pieces 22c and 22c are protruded to the inner peripheral side of the disc of a friction pad 14 by a distance equivalent to a back plate 14a. The tip thereof is bent internally of the friction pad 14 and hooked at the side of the disc rotor of the back plate 14a. Other two pad return pieces is protruded by a distance equivalent to the thickness of the back plate 14a with the two sides of the friction pad 14 therebetween, the tip thereof is bent internally of the friction pad 14 and hooked at the side of the disc rotor of the back plate 14a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle disc brake used in automobiles and motorcycles, and more particularly to a vehicle disc brake having a shim plate on the back surface of a friction pad.

[0002]

2. Description of the Related Art In a vehicle disc brake, a vibration noise called brake squeal may be generated during braking when the disc rotor and the friction pad lining are in sliding contact with each other. As disclosed in Japanese Utility Model Publication No. 59-21296, a shim plate made of a thin metal plate such as stainless steel is interposed between the rear surface of the friction pad and the piston for pushing the friction pad.

Each of the former disc brakes has a structure in which a plurality of engaging claws are provided on a shim plate, the engaging claws are locked in the holes of the piston, and the shim plate is attached to the piston. In addition to being common, the former disc brake has friction pads arranged on opposite sides of the disc rotor through the ceiling opening formed in the bridge portion of the caliper body.
When the pad receiving piece is projectingly provided on the shim plate and the hanger pin is pulled out when the friction pad is removed, the friction pad is held by the pad receiving portion without coming off.

Further, the latter disc brake has a structure in which a plurality of engaging claws are projected from the shim plate toward the friction pad side, and these elastic claws are locked in the opening formed on the back surface of the friction pad. After the brake is released, when the piston retreats into the cylinder hole by the restoring force of the angular seal interposed between the piston and the cylinder hole, the friction pad is forcibly pulled back from the disc rotor via the shim plate and The pad lining is prevented from being unevenly worn by being dragged by the disc rotor.

[0005]

In the former configuration, although the friction pad can be easily attached and detached through the ceiling opening, it does not have a means for returning the friction pad, so the friction pad can be slid by the disc rotor. The lining may wear unevenly. Also, in the latter configuration, since the shim plate is attached to both the piston and the friction pad,
Since the friction pad cannot be inserted and removed along the side surface of the disk rotor, the caliper body assembly must be removed from the vehicle body every time the friction pad is replaced or maintained.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a disc brake for a vehicle in which a friction pad can be easily attached and detached and in which uneven wear of the lining can be effectively prevented.

[0007]

According to the above-mentioned object, the first
According to the invention, a ceiling opening is formed in a bridge portion of a caliper body that is arranged so as to straddle the outside of the disc rotor, and a disc inner peripheral side of a friction pad that is arranged to face both sides of the disc rotor through the ceiling opening. Is held by a shim plate arranged on the back surface of the friction pad or a pad receiving portion extending from the operating portion of the caliper body, and is provided in the operating portion of the caliper body with opening toward the friction pad side. A disc brake for a vehicle, wherein a piston is inserted into a cylinder hole via a square seal, and the shim plate is attached to the piston. In the disc shim plate, the disc inner peripheral side of the friction pad and / or the friction pad The both ends of the pad protrude and the tip bends inward of the friction pad, pulling back the friction pad after braking is released from the side of the disc rotor. A is provided.

The shim plate may be provided with a pad slip-off preventing piece that elastically abuts on the disk outer peripheral side of the friction pad. It is also possible to provide engaging recesses on both side surfaces of the friction pad, and to provide a shim plate with pad retaining pieces that elastically engage with the engaging recesses.

[0009]

According to this structure, since the pad return piece of the shim plate projects to the disk inner peripheral side of the friction pad or the side portion of the friction pad, it does not prevent the friction pad from being inserted or removed through the ceiling opening. The tip of the pad returning piece is caught by the friction pad, and when the piston after braking is retracted into the cylinder hole by the restoring force of the angular seal, the friction pad is forcibly pulled back from the side surface of the disc rotor.

Further, the shim plate is provided with a pad retaining piece that elastically abuts on the disc outer peripheral side of the friction pad, or the engaging concave portion of the shim plate and the friction pad and the pad retaining piece are elastically engaged with the concave and convex portions. By doing so, it becomes possible to prevent the friction pad from coming off without using a separate retaining device such as a hanger pin, and without using a dedicated pad spring, it is possible to prevent rattling of the friction pad due to running vibration etc. obtain.

[0011]

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

1 to 4 show a first embodiment of the present invention, in which a caliper body 2 of a disc brake 1 is divided into a plurality of parts by dividing the center of a bridge portion 2c in parallel with the rotation direction A of the disc rotor 3. Cylinder holes 5, 6 and 7 having different caliber are arranged in parallel in the disk circumferential direction while being connected to bolts 4 and facing each other on both sides of the disk rotor 3 so as to face each other. , 6, 7 through the corner seals 8, 9, 10 are piston pots of 6 pots, in which the pistons 11, 12, 13 are inserted in a liquid-tight and movable manner, and the pistons 11, 2a, 2b of the pistons 11, A pair of friction pads 14 and 14 are arranged so as to face each other between 12 and 13 and the side surface of the disk rotor 3.

The cylinder holes 5, 6, and 7 are provided in the friction pad 14
The pistons 11, 12 and 13 are inserted in the cylinder holes 5, 6 and 7 with their bottomed cylindrical openings facing the friction pads. Cage, each piston 11, 12, 13 and cylinder hole 5,
Hydraulic chambers 15, 16 and 17 are defined between the bottom portions of 6 and 7. The three hydraulic chambers 15, 16 and 17 adjacent to each other in the action portions 2a and 2b respectively have the liquid passage hole 2d penetrating the partition wall.
, The two hydraulic chambers 15 on the disk entry side,
15 and the two hydraulic chambers 17, 17 on the disk feeding side are communicated with each other through a liquid passage hole 18 penetrating the inside of the bridge portion 2c.

A vehicle body mounting arm 2e is attached to one acting portion 2a.
The caliper body 2 is fixed to the vehicle body by bolting the vehicle body mounting arm 2e, and the working fluid pressurized by a separate hydraulic master linda (not shown) is connected to the union hole 19. 19 and further to the six hydraulic chambers 15 to 17 through the liquid passage holes 2d and 18. Further, a rectangular ceiling opening 20 is formed in the bridge portion 2c in such a size as to surround the friction pads 14, 14 disposed inside thereof, and the friction pads 14, 14 pass through the ceiling opening 20. It is designed to be inserted and removed.

Each of the friction pads 14 is constructed by adhering a lining 14b which is in sliding contact with the disc rotor 3 to the back plate 14a formed of a metal plate, and the action portions 2a and 2b sandwiching the ceiling opening 20. Hanger pin 2 that is hung on
1 is inserted into the pin hole 14c of the back plate 14a and is suspended between the pistons 11 to 13 and the side surface of the disc rotor 3 as described above. A shim plate 22 is arranged between the back plate 14a of the friction pad 14 and the pistons 11 to 13, and the shim plate 22 prevents the brake squeal during braking.

The shim plate 22 is provided on a shim plate body 22a which covers substantially the entire back surface of the back plate 14a, and six engaging claws 22b which vertically project in pairs in the piston direction.
Four pad return pieces 22c protruding toward the friction pad,
It has 22c, 22d, and 22d. The positions and intervals of the pair of engaging claws 22b and 22b correspond to the inner diameters of the pistons 11, 12 and 13, respectively.
Attaches the three sets of locking pawls 22b to the pistons 11, 1 respectively.
It is elastically attached to the holes 2 and 13.

The two pad return pieces 22c, 22c project from the both sides of the disc inner peripheral side edge of the shim plate body 22a to the disc inner peripheral side of the friction pad 14 by the thickness of the back plate 14a, and the tips thereof are the friction pads. It is formed in an L-shape that is bent inwardly of 14 and hooked on the disk rotor side surface of the back plate 14a. Also, the remaining two pad return pieces 22d, 2
2d is the total width of both sides of the shim plate body 22a in the vertical direction,
The friction pad 14 is formed in an L-shape so that both sides of the friction pad 14 are sandwiched and the thickness of the back plate 14a is projected, and the tip is bent inward of the friction pad 14 and hooked on the disk rotor side surface of the back plate 14a. The disc inner circumferential corner portion 14 is continuous with the above-mentioned pad return piece 22c.

The pad return pieces 22c, 22c of the friction pad 14 projecting toward the inner peripheral side of the disk also serve as known pad receiving portions, and the friction pad 14 inserted through the ceiling opening portion 20 of the bridge portion 2c has both sides. Pad return piece 22
c and 22c hold them without dropping them off, and the hanger pins 21 prevent them from coming off.
Of the pad return pieces 22d, 22d projecting on both sides of the
Guides the insertion and removal of the friction pad 14 well.

In this embodiment having such a configuration, the pistons 11, 12, 13 cause the respective corner seals 8, 9, 10 to be actuated by the hydraulic fluid supplied from the hydraulic master linder to the hydraulic chambers 15-17. While elastically deforming, the cylinder hole 5,
6 and 7 are moved toward the opening, and the pistons 11 to 11
13 presses the friction pad 14 via the shim plate body 22a of the shim plate 22, and the linings 14b and 14b of both friction pads 14 and 14 are brought into sliding contact with both side surfaces of the disk rotor 3 to perform a braking action. .

Further, when the above braking operation is released, the pistons 11, 12, 13 are moved to the respective corner seals 8, 9, 1 respectively.
The shim plate 22 integrally recedes as it recedes into the cylinder holes 5, 6, and 7 due to the restoring force of 0, and the friction pads 14 and 14 also return the pad returning pieces 22c, 2 of the shim plate 22.
It is forcibly pulled back from the disc rotor 3 by the engagement with 2c, 22d, 22d.

As a result, the lining 14b of the friction pad 14 is separated from the side surface of the disc rotor 3, so that the lining 14b is not dragged by the disc rotor 3 and is not unevenly worn. When the friction pad 14 is replaced or maintained through the ceiling opening 20 of the bridge portion 2c, the friction pad 14 from which the hanger pin 21 is pulled out is held without the inner pad return pieces 22c and 22c falling off. And the pad return pieces 22c, 22c
With the pad return pieces 22d and 22d on the side portions, it is possible to favorably guide the insertion and removal of the friction pad 14.
Particularly, in this embodiment, the pad return pieces 22c, 22c on the inner peripheral side are provided.
Also serves as a pad receiving part, so a separate caliper body 2
Since it is not necessary to provide a dedicated pad receiving portion on the action portions 2a and 2b and the shim plate 22, the economical efficiency is high.

FIG. 5 to FIG. 7 show a second embodiment of the present invention. In this embodiment, the hanger pin used in the first embodiment is omitted and the friction pad which replaces the hanger pin is prevented from coming off. The example which provided the means in the shim board is shown.

The shim plate 22 includes a shim plate body 22a, six engaging claws 22b, and four pad returning pieces 22c, 22c,
22d and 22d are provided as in the first embodiment. In addition, on the outer peripheral side edge of the disc of the shim plate body 22a,
Two pad retaining pieces 22e, 22e having elastic force
Are provided so as to project in a U-shape toward the friction pad, and the tip of the pad retaining piece 22e is raised outward as a tab piece 22f.

The pad retaining piece 22e allows the friction pad 14 to pass by pulling the knob piece 22f toward the piston, and the friction pad 14 inserted from the ceiling opening 20 is returned to the inner side of the disc. 22c, 22c
Then, by releasing the pulling of the knob piece 22f, the pad retaining pieces 22e, 22e elastically contact the disk outer peripheral side of the back plate 14a.

Although the present embodiment has an extremely simple structure in which the pad retaining pieces 22e, 22e are added to the shim plate 22, the pad retaining pieces 22e, 22e are not provided.
Since the friction pad 14 is prevented from coming off, a dedicated retaining means such as a hanger pin is not required, and the pad retaining pieces 22e and 22e hold the friction pad 14 together with the pad returning pieces 22c and 22c without rattling. The pad spring that was used exclusively for the past can be eliminated,
It is highly effective in terms of workability, assembly, economy, and weight reduction.

In the third embodiment shown in FIG. 8, the pad retaining piece 22e of the second embodiment is provided inside the friction pad 14 at the disk outer peripheral edge of the pad returning piece 22d protruding from the side portion of the friction pad 14. It is provided so as to project toward.

FIG. 9 shows a fourth embodiment of the present invention, in which the engaging recess 14d is formed substantially at the center of the side surface of the back plate 14a of the friction pad 14.
Is formed in the torque receiving portion 2f of the caliper body 2 that supports the side surface of the back plate 14a during braking, and the escape recess 2g is formed in the torque receiving portion 2f.
Is provided so as to face the engagement recess 14d of the friction pad 14. The pad return piece 22d of the shim plate 22 has a pad retaining piece that protrudes in a V shape toward the back plate 14a at a position between the escape recess 2g of the caliper body 2 and the engagement recess 14d of the friction pad 14. 22g is provided with a pad return piece 22d at the lower end.

When the friction pad 14 passes, the pad retaining piece 22d is elastically deformed by being pressed by the back plate 14a and retracts into the escape recess 2g of the torque receiving portion 2f so that the friction pad 14 can be inserted and removed. When the friction pad 14 is held by the pad return pieces 22c, 22c on the inner circumference side of the disc and the engagement recess 14d of the back plate 14a is positioned inward, the friction pad 14 projects into the engagement recess 14d and is elastic. To prevent the friction pad 14 from coming off and prevent rattling due to traveling vibration or the like.

In each of the above-mentioned embodiments, the tip of the pad return piece is brought into contact with the side surface of the disk rotor of the back plate to pull back the friction pad. However, the side surface of the back plate or lining or the side surface of the boundary between them. It is also possible to form a slit in and to insert the tip of the pad return piece into this slit. When slitting the lining, it is desirable that the back plate side does not affect the wear limit of the lining. If the pad return piece is provided on either the inner side of the disc of the friction pad or on both sides of the friction pad, the return of the friction pad can be performed, but if the inner side of the disc is omitted, it will be attached to the caliper body. Since it is necessary to separately provide a dedicated pad receiving piece, it is advantageous to provide a pad returning piece that also serves as a pad receiving piece at least on the inner peripheral side of the disc.

Further, the pad return piece of the present invention may be divided into a plurality of pieces other than those in the above-mentioned embodiments, or conversely may be integrally continuous. Further, the shape, the number, and the mounting position of the pad retaining pieces can be appropriately changed. In addition to the piston facing type shown in the embodiment, the present invention can be applied to a pin slide type caliper body.

[0031]

According to the present invention, the shim plate disposed between the friction pad and the piston is attached to the piston, and the shim plate is provided on the inner peripheral side of the disc of the friction pad and / or the friction pad. By providing a pad return piece that protrudes across both sides and whose tip bends inward of the friction pad, the friction pad after braking is released from the disc rotor without hindering the removal and insertion of the friction pad through the ceiling opening. Since it can be reliably pulled back from the side surface, there is no problem that the lining is dragged by the disc rotor to cause uneven wear.

Further, when the pad return pieces are provided on both sides of the friction pad, the friction pad can be guided to perform the insertion / removal satisfactorily, and the pad return piece can be provided on the inner peripheral side of the disc of the friction pad. When provided, this pad return piece also serves as a pad receiving portion, so it is not necessary to separately provide a dedicated pad receiving portion on the action portion of the caliper body or the shim plate, which contributes to weight reduction and workability.

Further, the above-mentioned shim plate is provided with a pad retaining piece that elastically abuts on the disc outer peripheral side of the friction pad, or engaging concave portions are provided on both side surfaces of the friction pad. By providing a pad retaining piece that elastically engages with the mating recess, the friction pad can be retained without using a separate retaining device such as a hanger pin, and without using a dedicated pad spring. Since the friction pad can be prevented from rattling due to traveling vibration, etc., it greatly contributes to workability, assembling efficiency, economy and weight reduction.

[Brief description of drawings]

FIG. 1 is a sectional view taken along the line II of FIG. 3;

FIG. 2 is a partial cross-sectional plan view of the disc brake showing the first embodiment of the present invention.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an exploded perspective view of a friction pad and a shim plate showing the first embodiment of the present invention.

FIG. 5 is a sectional front view of a disc brake showing a second embodiment of the present invention.

6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is an exploded perspective view of a friction pad and a shim plate showing a second embodiment of the present invention.

FIG. 8 is a sectional view of an essential part of a disc brake showing a third embodiment of the present invention.

FIG. 9 is a sectional view of an essential part of a disc brake showing a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Disc brake 2 ... Caliper body 2a, 2b ... Action part 2c ... Bridge part 2f ... Torque receiving part 2g ... Escape recess 5,6, 7 ... Cylinder hole 8, 9, 10 ... Square seal 11, 12, 13 ... Piston 14 ... Friction pad 14a ... Back plate 14b ... Lining 14d ... Engagement recessed parts 15, 16, 17 ... Hydraulic chamber 20 ... Ceiling opening 21 ... Hanger pin 22 ... Shim plate 22a ... Shim plate body 22b ... Engagement claw 22c, 22d ... Pad return piece 22e ... Pad retaining piece 22f ... Picking piece

Claims (3)

[Claims] 1. A ceiling opening is formed in a bridge portion of a caliper body which is arranged so as to straddle the outside of a disk rotor,
A pad receiving portion extending from the working portion of the shim plate or the caliper body, which is disposed on the back surface of the friction pad, on the inner peripheral side of the disc of the friction pad that is arranged to face both sides of the disc rotor through the ceiling opening. And hold it at
In a disc brake for a vehicle, wherein a piston is inserted into a cylinder hole provided in an action portion of the caliper body and opened toward a friction pad side through a corner seal, and the shim plate is attached to the piston. A pad that protrudes on the plate while sandwiching the inner peripheral side of the friction pad and / or both sides of the friction pad, and the tip bends inward of the friction pad to pull back the friction pad after braking release from the side surface of the disc rotor. A disc brake for a vehicle, which is provided with a return piece. 2. The disc brake for a vehicle according to claim 1, wherein the shim plate is provided with a pad retaining piece that elastically abuts the disc outer peripheral side of the friction pad. 3. The friction recesses are provided with engaging recesses on both side surfaces thereof, and the shim plate is provided with protruding pad retaining pieces that elastically engage with the engaging recesses. Disc brake for vehicle as described.