JPH0526348Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vehicle disc brake that is applied to vehicles such as four-wheeled vehicles and motorcycles.

[Conventional technology]

The friction pads used in disc brakes are
In general, it has a structure in which a lining that is pressed against the side surface of the disc rotor is joined to a back plate that is pushed by a pad pushing member such as a reaction part of a piston or caliper. 52
-There is one shown in Publication No. 104085.

This friction pad has a plurality of binding holes in the back plate, and when molding the lining onto the back plate, the binding holes are filled with lining material, and the lining material is made to protrude from the back side of the back plate. By integrally forming a damping seat that abuts against the reaction part of the piston or caliper, squealing when the brake is activated is prevented.

[The problem that the idea aims to solve]

These damping seats are processed to have the same height in post-processing after joining, but the piston and caliper repeatedly collide with the lining, which is less hard than the metal backing plate, and are repeatedly braked. The damping seats individually wear out, creating height differences on the surface, and the contact between the damping seats and the reaction part of the piston or caliper becomes uneven, causing uneven wear of the lining, especially on the piston. Rotating force is generated during operation, making uneven wear more pronounced.

Furthermore, since the edge of the binding hole remains exposed on the back surface of the back plate, water enters the binding hole from the edge and accumulates therein, causing rust.

The present invention was developed against this background, and its purpose is to improve the bonding force by filling the binding holes with a lining, while also pushing the friction pads evenly. To provide a disc brake for a vehicle, which can ensure flatness between a friction pad and a reaction part of a piston or a caliper, prevent uneven wear of a lining, and prevent rust from entering a binding hole. It is in.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention has a friction pad arranged on the side of the disc rotor, which is made up of a back plate that is pushed by the reaction part of the piston or caliper, and a lining that is pressed into contact with the disc rotor. In the disc brake for a vehicle, a plurality of binding holes are formed in the back plate of the friction pad, and the binding holes are filled with a lining material forming the lining, and the lining material is protruded from the back surface of the back plate. Then, fill it up to a diameter larger than the binding hole, and on the other hand,
The reaction part of the piston or caliper is provided with a plurality of escape recesses for the build-up of the back plate, which are opened on the pad pressing side, and the pad pressing side is brought into contact with the back side of the back plate.

[Action]

The reaction part of the piston or caliper straddles the built-up part on the back of the back plate with an escape recess, and the tip of the piston or the inner surface of the reaction part is brought into direct contact with the back of the flat back plate to push the friction pad. move. As a result, the contact between the piston or the reaction part and the back surface of the back plate is maintained in parallel, and the pushing force acts uniformly on the friction pad, thereby preventing uneven wear of the lining.

In addition, since the opening of the binding hole on the back surface of the back plate is covered with a large-diameter built-up portion, water does not infiltrate into the hole.

Further, even if the piston is subjected to rotational force, the escape recess comes into contact with the built-up portion and prevents this.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

Reference numeral 1 designates a disc brake, and a floating caliper 4 is supported by a bracket 3 fixed to the vehicle body on one side of a disc rotor 2 so as to be movable in the disc axial direction.

The caliper 4 has an action part 4a disposed on the side of the bracket 3, a reaction part 4b disposed opposite to the side opposite to the bracket with the disc rotor 2 in between, and a bridge part 4c connecting these parts across the disc rotor 2. It is made up of

The bracket 3 has a bridge portion 4c sandwiched therebetween.
Support arms 3 arranged in parallel around the outer periphery of the disc rotor 2
a, 3a are extended, and the caliper 4 has attachment arms 4d, 4d protruding from both sides of the action portion 4a.
Support arms 3a, 3a are attached via sliding pins (not shown).
is maintained.

A pair of friction pads 5 and 6 are provided between the action part 4a and the reaction part 4b, facing each other with the disc rotor 2 in between. Each friction pad 5, 6
consists of a lining 7 and a metal back plate 8, and has tabs 8a, 8a protruding from both sides of the back plate 8.
to each locking step 3b of the support arms 3a, 3a,
A pad spring 10 is suspended via a retainer 9 and is attached to the inside of the bridge portion 4c.
The disk is resiliently supported toward the center of the disk.

A square seal 11 is fitted into a cylinder hole 4e formed by opening the disk rotor 2 side in the action part 4a, and a corner seal 11 is fitted into the cylinder hole 4e to push the friction pad 5 on the action part 4a side. piston 12
is inserted in a fluid-tight and movable manner with the open end facing the disk rotor 2, and is further inserted into the cylinder hole 4.
A bellows-shaped dust boot 13 that protects the cylinder hole 4e from dust is attached between the outer periphery of the mouth portion of the cylinder e and the tip of the piston 12.

A hydraulic chamber 14 connected to a master cylinder (not shown) for generating hydraulic pressure is defined between the bottom of the cylinder hole 4e and the piston 12, and pressure fluid is supplied from the hydraulic master cylinder to the hydraulic chamber 14. When this happens, the piston 12 moves forward through the cylinder hole 4e and presses the friction pad 5 against one side of the disc rotor 2. Then, due to this reaction, the caliper 4 moves toward the action section 4a, and the reaction section 4b is moved toward the action section 4a. A braking action is performed by pressing the friction pad 6 against the other side of the disc rotor 2.

Each of the back plates 8 of the friction pads 5 and 6 is provided with four binding holes 8b that open on the back surface 8c. These binding holes 8b are filled with a lining material at the same time as the lining 7 is formed, and this lining material is further made to protrude from the back surface 8c of the back plate 8, so that a built-up portion 7a having a larger diameter than the binding holes 8b is formed. , thereby increasing the bonding force between the lining 7 and the back plate 8.

Each built-up portion 7a protruding from the back surface 8c of the back plate 8 is
It is provided so as to be located approximately on the diameter of the piston 12.

The opening of the piston 12 that pushes the friction pad 5 has an escape recess 12a that covers these built-up parts 7a.
and four pushing protrusions 12b are formed alternately, and the protrusions 12b of the piston 12 are connected to the built-up portion 7.
a, and the tip surface 12c of the protrusion 12b
is provided in contact with the back surface 8c of the back plate 8.

On the other hand, the reaction part 4b that pushes the friction pad 6 is provided with a notch 4f in the center with the cylinder center side open to form two reaction claws. 4g inner surface for pushing that comes into contact
Three relief recesses 4h, which are slightly wider than the built-up portion 7a, are formed radially from the notch 4f.

Of the built-up parts 7a of the friction pad 6, three are accommodated in the escape recess 4h, and the other one is arranged in the notch 4f, and the inner surface 4g is in contact with the back surface 8c of the back plate 8. are provided in contact with each other.

These relief recesses 12a, 4h are formed with a size and depth that do not directly interfere with the built-up portion 7a of the lining 7.

The tip surface 12c of the piston 12 and the reaction part 4b
The inner surface 4g of the recess 12 escapes the built-up part 7a.
a, 4h, and is provided in direct contact with the flat back surface 8c of the back plate 8, so that the piston 12
Since the pushing force of the reaction portion 4b acts uniformly on the friction pads 5 and 6 without causing an uneven load, no uneven friction is applied to the lining 7.

In addition, even if the piston 12 receives a rotating force during operation, the projection 12b engages with the padding 7a to stop the piston 12 from rotating, thereby preventing damage to the square seal 11 and the dust boot 13. In particular, this is a disk brake with a parking brake having a hydraulic and mechanical operating mechanism and further equipped with an auto adjuster that automatically adjusts the braking gap (see, for example, Japanese Utility Model Publication No. 62-21144).
In the previous design, the piston was prone to rotation, and so the tip of the piston was fitted into the back surface of the back plate of the friction pad to prevent rotation, which meant that impact noise between the metal piston and the back plate could not be avoided. However, with this structure, the protrusion 12b cushions and engages with the padded portion 7a of the lining material, preventing the generation of impact noise and allowing the piston 12 to be positioned for reliable adjustment operation.

Furthermore, in the friction pads 5 and 6, since the built-up portion 7a covers the edge of the back surface 8c, water does not infiltrate into the binding hole 8b, effectively preventing the occurrence of rust that causes corrosion. Since the raised portion 7a does not require a damping seat as in the conventional example, processing of the surface height is not required.

Furthermore, since the friction pads 5 and 6 have the same shape, they can be used in common, and there is no risk of incorrect assembly when reassembling.

Furthermore, since the contact area between the tip end surface 12c of the piston 12 and the inner surface 4g of the reaction part 4b with the back surface 8c of the back plate 8 is reduced by the formation of the relief recesses 12a and 4h, the braking heat from the back plate 8 is reduced. Moreover, since the relief recesses 12a and 4h are set to a size and depth that do not directly interfere with the built-up portion 7a of the lining 7, braking heat can be released to the outside, cooling the piston 12 and the reaction section 4b. It has the effect of

Particularly, on the acting part 4a side to which the pressure fluid is supplied, the braking heat in the piston 12 is exchanged with outside air through the gap between the escape recess 12a and the built-up part 7a, so the cooling efficiency of the piston 12 is improved. This suppresses the occurrence of vapor lock due to a rise in the temperature of the pressure fluid.

FIG. 5 shows another embodiment of the present invention, in which the action portion 4a is provided such that the inner surface 4i surrounding the mouth of the cylinder hole 4e is close to the tip end surface 12c when the piston 12 is initially set. A plurality of relief recesses 4j are formed on the inner surface 4i so as to be continuous with the outer circumference of the relief recess 12a of the piston 12, and the cylinder hole 12 has a plurality of relief recesses 4j and the corner seal 11. In between, ring-shaped dust boots 1
5 is fitted.

The built-up portion 7a of the friction pad 5 is connected to the piston 12.
A part of the inner side of the piston 12, which is provided so as to straddle the inner surface 4i of the action part 4a and which is arranged on the diameter of the piston 12, is covered with an escape recess 12a, and the piston 1
Most of the outside located on the outer periphery of 2 is the acting part 4a.
It is accommodated in the escape recess 4j.

In the present invention, as in the above embodiment, at least a part of the built-up portion 7a is covered with the escape recess 12a,
The tip end surface 12c of the piston 12 is connected to the back surface 8 of the back plate 8.
It is sufficient that the piston 12 is brought into direct contact with the friction pad 5 and pressed against the friction pad 5 evenly, and the piston 12 is prevented from rotating.
This does not prevent the formation of the relief recess 4j in the action portion 4a.

In the above embodiment, the means of the present invention was applied to both the piston and the reaction part of the caliper so that the friction pads could be shared, but it may also be applied to only one of them.

Further, the shapes and formation positions of the built-up portion and the recessed portion may be changed in both of the above-mentioned embodiments, and furthermore, it is possible to implement a type in which the piston is used in the opposite direction to that of both embodiments.

[Effects of the invention] As described above, the disc brake of the invention has the following effects:
A plurality of binding holes are formed in the back plate of the friction pad, and these binding holes are filled with a lining material that forms a lining, and the lining material is made to protrude from the back of the back plate to form a hole with a diameter larger than that of the binding holes. Add meat to the pan, and
The reaction part of the piston or caliper that pushes the friction pad is provided with a plurality of escape recesses for this built-up part with openings on the pad pressing side, and the pad pressing side is brought into contact with the back of the back plate. The bonding force between the plate and the lining is further increased than in the past, and the pad pressing side surface can evenly press the flat back surface of the back plate, preventing uneven wear of the lining.

Furthermore, since the built-up part covers the edge of the binding hole on the back of the back plate, there is no water intrusion into the hole and rust can be prevented.Moreover, the built-up part does not have a damping seat like the conventional example. Since no surface processing is required, surface processing can be omitted.

It also effectively prevents piston rotation and prevents damage to seals and boots. In particular, in disc brakes with parking brakes equipped with an auto adjuster for adjusting the braking gap, it is possible to prevent the occurrence of collision noise between the piston and the back plate, and to position the piston by preventing it from rotating. Reliable adjustment operation can be performed.

Furthermore, from the gap between the built-up part and the relief recess,
Since braking heat can be released, it can be expected to have a cooling effect on the piston and caliper.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention,
Figure 1 is a sectional side view of the disc brake, Figure 2 is a rear view, Figure 3 is an exploded perspective view of the friction pad and piston, Figure 4 is a rear view of the friction pad combined with the piston, Figure 5 FIG. 3 is a cross-sectional view of main parts showing another embodiment. 1... Disc brake, 2... Disc rotor, 4... Caliper, 4a... Acting part, 4b...
Reaction part, 4g...inner surface, 4h...relief recess,
5, 6...Friction pad, 7...Lining, 7a
...Build-up portion, 8...Metal back plate, 8b...Binding hole, 8c...Back surface, 12...Piston, 12a
...Escape recess, 12b...Protrusion for pushing, 12c
...Tip surface.

Claims (1)

[Scope of utility model registration request] In a disc brake for a vehicle, a friction pad is arranged on the side of the disc rotor, which is made up of a back plate that is pushed by the reaction part of a piston or caliper, and a lining that is pressed against the disc rotor.
forming a plurality of binding holes in the back plate of the friction pad;
These binding holes are filled with a lining material forming the lining, and the lining material is made to protrude from the back of the back plate and is built up to a diameter larger than that of the binding holes, while the reaction part of the piston or caliper is A disc brake for a vehicle, characterized in that a plurality of escape recesses are provided in the built-up portion of the back plate and open on the pad pressing side, and the pad pressing side is brought into contact with the back surface of the back plate.