JPH042816B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a disc brake shim for reducing disc brake noise.

B. Prior Art In general, in disc brakes, as shown in Figure 1A, there is a gap between the piston 1 and the back plate 3 of the pad 2, and in the case of a floating caliper type, there is a gap between the caliper 4 and the back plate 3. A shim 5 is interposed between the two to reduce noise during braking. That is, the actuation of the piston 1 presses the disc 7 between it and the pad 2, and the shim moves to reduce the noise generated at this time.

As shown in Figure 1B, the disc brake shim described above is often made of a metal plate 5-1 coated with oil-proof and vibration-proof rubber 5-2 on one or both sides, and its damping performance at high temperatures is satisfactory. There are disadvantages that cannot be obtained.

C. Objective of the Invention or Problems to be Solved by the Invention The shim of the present invention is intended to provide a shim for a disc brake that can provide sufficiently satisfactory damping performance even in a high temperature range.

D. Structure of the Invention or Problem Solving Means The shim of the present invention is a shim for a disc brake, characterized in that a rubber composition prepared by kneading 100 parts by weight or more of furnace carbon powder with 100 parts by weight of a rubber component is adhered and coated on a metal plate. The above-mentioned rubber component is based on acrylonitrile rubber in terms of oil and vibration resistance.

In addition, 100 parts by weight of high nitrile solid rubber containing 35% by weight or more of nitrile and 2 to 2 parts by weight of semi-liquid nitrile rubber.
It is advantageous to use 15 parts by weight. Further, in carrying out the present invention, it is more advantageous to mix graphite in an amount of 5 parts by weight or more based on the furnace carbon powder in the rubber composition.

Although the manufacturing method of the shim of the present invention is not limited in any way, the above-mentioned rubber composition is pasted and coated to a predetermined thickness on one or both sides of a thin iron plate such as steel, with or without a brimer layer. It can be manufactured by

E Effect If the furnace carbon powder is 90 parts by weight or less per 100 parts by weight of the rubber component, the heating temperature is 100 to 150°C or
The damping performance in the high temperature range of 150°C or higher decreases as the temperature rises, making it impossible to obtain sufficient damping performance in the high temperature range, but according to the present invention, 100 parts by weight or more of furnace carbon powder is added to 100 parts by weight of the rubber component. When combined, it shows the same damping performance as the above case in the low temperature range of 100℃ or less, and in the high temperature range of 100 to 150℃ or more, contrary to the above case, the damping performance improves as the temperature rises. However, a sufficiently satisfactory high-temperature region damping performance was obtained.

F Example A shim product was prepared by adhering and coating a base steel material with a thickness of 0.38 mm with a rubber composition having each of the following formulations to a total thickness of 0.64 mm.

Example 1 Compound (parts by weight) Nitrile butadiene rubber 100.0 Zinc white 5.0 Stearic acid 1.0 Furnace carbon powder 100.0 Graphite 10.0 Coumaron oil 10.0 Plasticizer DBP 10.0 Accelerator TT 1.5 Vulcanizing agent R 1.5 Anti-aging agent NBC 1.0 Example 2. Composition In the formulation of Example 1, furnace carbon powder
The formulation was the same except that 120 parts by weight was added instead of 100 parts by weight.

Comparative Example 1 Formulation Furnace Carbon Powder 60 in Example 1 Formulation
The formulation was the same as in Example 1 except that part by weight was added.

The furnace carbon used above was manufactured by Asahi Carbon Co., Ltd. under the trade name #60FEF, and its physical properties were as follows.

Average particle diameter (electron microscopy) 51 mμ Specific surface area (nitrogen adsorption method) 58 m ² /g Iodine adsorption amount 42 mg/g Ash content 0.1% Volatile matter 1.0% G Effect of the invention These Examples 1 and 2 and Comparative Example 1 About sim products: 1 temperature cycle, 2 heat aging resistance, 3 cold resistance,
Test results for 4: ozone resistance, 5: brake fluid resistance, 6: grease resistance, 7: bending adhesion, and 8: brake operation durability all showed good results. In addition, as shown in Figure 2, the products of Examples 1 and 2 showed superior performance compared to the product of Comparative Example 1 in terms of damping performance at different temperatures, especially in high-temperature range damping performance. A remarkable improvement in high-temperature damping performance was observed as the temperature increased.

[Brief explanation of drawings]

Figure 1 A is a schematic diagram of a disc brake using shims, B is a partial sectional view of the shim, and Figure 2 is a logarithmic damping ratio showing the damping properties of each shim according to temperature in Examples 1, 2 and Comparative Example 1. It is a chart showing the relationship between and temperature.

Claims (1)

[Scope of Claims] 1. A shim for a disc brake, characterized in that a metal plate is coated with a rubber composition prepared by kneading 100 parts by weight or more of furnace carbon powder with 100 parts by weight of a rubber component. 2 The rubber component is based on acrylonitrile rubber, and acrylonitrile rubber is a high nitrile solid rubber containing 35% by weight or more of nitrile.
A shim for a disc brake according to claim 1, comprising 100 parts by weight of semi-liquid nitrile rubber and 2 to 15 parts by weight of semi-liquid nitrile rubber. 3. The disc brake shim according to claim 1 or 2, which uses a rubber composition in which 5% by weight or more of graphite is mixed with furnace carbon powder.