JPS59131045A - Disk brake pad - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to disc brake pads, and more particularly to disc brake pads for use with shims behind their backplates.

In disc brakes for vehicles such as automobiles, the vehicle is braked by pressing a disc brake pad, which is constructed by attaching a friction material to a steel pack plate, against a brake disc. The pressing force is applied to the disk brake pad by a hydraulic piston in the brake caliper, and in a conventional brake caliper one piston is pressed against the back brake pad (K) of at least one disk brake pad. In some cases, one caliper is equipped with two or more pistons, but the caliper acts on only one piston to press one pad directly against the disk, and the reaction force causes the opposite pad to move in a circular motion. Pull it to the board.

It is common practice to use various types of shims on the back of disc brake pads to reduce noise, primarily by damping, or in some cases to change the center of gusset pressure.

There are several ways to attach shims to pads. In the case of metal shims, this is done by gripping the edges of the pack plate of the pad with clips. Alternatively, the shim is adhered to the pack plate by a pressure sensitive adhesive or a thermosetting adhesive. Still another method is to form a shaped shim onto the back plate by heat and pressure when molding the disc brake pad.

However, the above-mentioned sims have traditionally had various drawbacks and problems. For example, when shims are attached using pressure sensitive adhesives, there is a problem with certain brake caliper designs where the shims tend to move out of position under the effects of radial forces on them.

Thermosetting adhesives are expensive and unsuitable for making disc brake pads, and it is difficult to create an adhesive that can withstand the high temperatures that are repeatedly applied to the adhesive each time the brake is used.

Wire mesh shims generally have the disadvantage that they do not have the same noise damping effect as non-metal maple or wire and rubber sandwich shims.

The inventors have therefore discovered a means of attaching and utilizing shims that eliminates many of the disadvantages mentioned above.

The present invention is a shim for a disc brake pad, which includes:
A shim pad of heat-resistant composite material is provided, and a wire mesh clip overlapping the shim pad sets the shim pad in position relative to the pack plate of the disc brake pad during use; A shim configured to be clipped into the end of a brake piston within a disc brake caliper is provided.

The metal clip is preferably configured to prevent direct contact between the piston and the shim pad, thus preventing the annular piston from cutting into the shim pad. The preferably worn metal clip does not straddle the shim pad, so all pressure from the giston is transmitted through the shim pad, where the best damping effect is achieved.

The metal clip is preferably in the form of a plate that overlaps the shim pad and has some shape providing means for locating the shim pad, such as a recessed area into which the shim pad fits, or a plurality of plates for locating the edge of the shim pad. It has a shape that creates a protrusion. The shim pad may be glued to the metal clip if desired.

The piston in a disc brake pad caliper is typically annular in the portion that is pressed against the back plate of the disc pad. Therefore, in the present invention, the metal clip preferably has three
There may be one or more upright clip members.

The shim pad is made of a composite material that withstands the pressure applied to the brake piston in a wide range of temperatures, from below 0°C to above 400°C, while protected by a gold maple clip.

The preferred composite material includes reinforcing fibers bonded with a suitably thermoset polymer, such as a rubber such as nitrile rubber or a resin such as phenolic, and which does not melt or significantly deteriorate under the conditions of use. There are things that include. Mixtures of rubber and resin could also be used.

The composite material is preferably a material with relatively low thermal conductivity that acts as a thermal barrier between the brake pad backplate and the brake piston. This material reduces the flow of heat from the disc brake pad P to the hydraulic piston and thus to the brake fluid. Such heat flow is particularly problematic when non-asbestos brake pads are used, which have much higher thermal conductivity than asbestos brake pads.

Composite materials used include compressed asbestos fiber materials with rubber or resin binders, resin-bonded and glass-fibre reinforced materials and, for example, rubber-bonded glass fibers, inorganic fibers or aromatic polyamide fibers. Non-asbestos materials equivalent to compressed asbestos fiber bonded materials are included, such as sheets of heat-resistant fibers such as fibrous materials. One such material
Published European Patent Application No. 8230115
No. 1.5 (Publication No. 0060664) K is described.

Preferably, the composite material is such that its fibers are oriented substantially in the direction of the plane of the seat to provide good strength against the compressive forces exerted by the brake piston during use of the shim pad.

If necessary, the shim pad may be limited to only the area of the back plate that the piston rests on, especially if it is thermally insulating. This reduces the effectiveness of heat dissipation from the disc brake pads with internal overheating. It will be appreciated that during use, the surface of the disc brake pad heats up rapidly due to friction against the brake disc. If the back side of the pad is covered with a thermally insulating material, the only surface involved in heat dissipation is the edge of the pad, which can be disadvantageous.

The present invention also provides a disc brake assembly comprising: a brake caliper having at least one brake piston;
a pair of disc brake pads and a thermally conductive barrier interposed between the brake piston and the disc brake pads against which the toning stone presses during use; A disc brake assembly is provided that includes a conductive composite shim pad and a device for holding the shim pad in position between the disc brake pad and the brake piston.

The detailed description will be continued below with reference to the attached drawings.

As shown in Figures 1 and 2, the disk plate P
is constructed by molding a friction material rose F2 on the back plate 1. A shim on the pack plate 1 is constructed by overlaying a galvanized steel clip 3 onto a shim pad 4 of compressed asbestos fiber composite material. As shown in FIG. 3, the steel clip 3 overlies a shim pad 4 and a retaining ridge 5 is provided on the periphery of the clip 3 which serves as a device for setting the shim pad 4 in position below the clip 3. The clip 3 has three rising clip members 6
．． 7.8, these clip members fit inside the annular brake piston 9 and engage the inner wall thereof, thereby securing the metal clip 3 to the end of the piston 9.

In the variant embodiment shown in FIGS. 4 and 5, the disc brake pad with pack plate 10 and friction material pad 11 is provided with a shim consisting of a steel clip 12 and a shim pad 13. Again, the clip 12 overlies the shim pad 13 and is provided with a recess 14 which serves as a positioning device for the shim pad. 6 clip members 1
5°16.17 connects the clip 12 to the brake piston 18
and the metal clip 12 extends beyond the sides of the shim pad to the opposite edges of the pack plate of the disc brake pad and includes opposite portions 19 and 20, thereby providing positioning relative to the brake caliper assembly. is ensured and the possibility of rotation of the metal clip and shim pad is prevented.

In both embodiments shown, metal clips 3 and 1
It will be appreciated that the clips 3.2 do not contact the pack plates 1 and 10, but their clips 3.12 are made in the form of a plate overlying the shim pad, on which the hydraulic pins can rest.

In either case, a shim pad positioning device is provided so that the shim pad is positioned only in the contact area of the piston, thereby reducing the size of the shim pad and the clip.

If desired, the annular shim pad may be made to closely match the shape of the shim.

[Brief explanation of the drawing]

1 is a rear view of a disc brake pad with a shim according to the invention; 2 FIG. 2 is a side view of the assembly shown in FIG. 1 with its brake piston shown in section; FIG. FIG. 4 is a rear view of a disc brake pad with a shim according to another embodiment of the invention; FIG. is a cross-sectional view taken along line B-B of the assembly of Figure 4; Figure 6 is a section of the shim of Figure 4 in place;
- It is a detailed sectional view taken along the A line. 1.10... disc brake pad pack plate,
2.11...Brake pad, 3.12...Shim metal clip, 4.13...Shim para r15°14.
...Shim pad position setting device, 6.7.8°15.16
, 17... Standing clip member, 9° 18... Brake piston, 19.20... Side part. Attorney: Akira Asamura Procedural amendment (method) Mr. Commissioner of the Japan Patent Office 1, dated 1996/1996, 7. j2(, l* '2
, Name of the invention based on circle 1, Receiver IF 3, Person making the amendment Relationship with the case Patent applicant address 4, Agent 5, Date of amendment order July 7, 1939 6, Amendment Number of inventions increased due to 7. Engraving of drawings subject to amendment (no change in content) 8. Contents of amendment As shown in the attached sheet

Claims (1)

Claims: (1) A shim for a disc brake pad, comprising a shim pad made of a heat-resistant composite material, and for setting the shim pad in a predetermined position relative to the pack plate of the disc brake pad during use. A shim configured such that a metal clip superimposed on the shim pad sets the shim in its predetermined position and is configured to clip into the end of a brake piston within a disc brake caliper. (2. The shim according to claim 1, in which the gold maple clip is installed to prevent the shim pad from coming into direct contact with the brake piston during use. (3) Claim 1 The shim according to claim 1 or 2, wherein the metal clip has a retaining lip on the edge of the shim pad that serves as a positioning device for the shim pad. (4) The shim according to claim 1 or 2, or 3rd, 3rd
The shim of Clause 1, wherein the gold-striped clip is comprised of a metal plate having a plurality of raised clip members that engage the inner surface of the annular brake piston. (5) The shim according to claim 1, wherein the shim pad is a thermally insulating material. (6) Claims In the shim according to any one of the preceding paragraphs, in order to prevent the disc brake pad from overheating during use, the shim pad is substantially attached to the disc brake pad back plate that contacts the brake piston during use. (7) A shim according to any one of the preceding claims, wherein the shim pad is oriented substantially in the direction of the plane of the sheet of fiber-reinforced composite material. A sim made of. (8) The shim according to claim 7, wherein the fiber is a heat-resistant fiber selected from asbestos, glass, inorganic fiber, and synthetic organic fiber. (9) The shim according to claim 7, wherein the composite material is a binder containing both or one of thermosetting rubber and thermosetting resin. 00) The shim of any preceding claim, wherein the shim pad is made from compressed asbestos fiber material bonded with a polymer. αυ A shim according to any one of claims 1 to 9, wherein the shim pad is made from a resin bonded and glass fiber reinforced material. α2. A disc brake pad and shim assembly comprising a shim according to claim 1. (13) In a disc brake assembly, a brake caliper having at least one brake piston, 1
a pair of disc brake parts r1, and a thermally conductive barrier inserted between the brake piston and the disc brake pad against which the piston presses in use, the barrier having a relatively low thermal conductivity. a composite shim pad, and
A disc brake assembly including a device for holding the shim pad in position between the disc brake pad and the brake piston. I. The disc brake assembly of claim 16, wherein the shim pad is a sheet of composite material reinforced with fibers oriented substantially in the direction of the plane of the sheet. Q51: The disc brake assembly according to claim 14, wherein the fiber is a heat-resistant fiber selected from asbestos, glass, inorganic fiber, and synthetic organic fiber.