JPS61188425A - Production of friction material - Google Patents

Abstract

PURPOSE:To obtain a friction material having holds or grooves of any desired shape easily at low cost, by embedding a low-melting alloy member in a starting friction material, preforming this material, curing the perform by heating in a mold and post-curing it by heating to allow the alloy member to melt and flow out. CONSTITUTION:In producing a friction material 5 by (a) preforming a friction material 2 comprising a base, a binder, etc., (b) curing the preform 3 by heating in a mold and (c) post-curing it by further heating, said preforming is performed after a low-melting alloy member 1 having a m.p. lying in the range of from the temperature at which heat-curing in step (b) is performed and the temperature at which the post curing in step (c) is performed is embedded in the material, and the low-melting alloy member 1 embedded in step (a) is allowed to melt and flow out during the post curing in step (c). In this way, holes or grooves 4 of any desired shape can be formed on the surface of friction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a *ring member having holes or grooves of arbitrary shapes on at least the friction surface.

[Prior Art] Resin-molded friction materials thermally decompose contained organic components (binding resin, friction dust such as cashew dust and rubber dust) due to heat generated during mechanical decomposition, and decomposition gas is generated. When the AI rubbing conditions become severe, gas is generated rapidly, a gas film is formed on the RAM surface, and the FJ friction coefficient rapidly decreases.

A so-called fade phenomenon occurs. If holes or grooves are provided on the friction surface, the gas will be J1! It is known that the fading phenomenon is alleviated because it escapes from the rubbing surface (Jikko Kosho 58-22).
533). □ According to the conventional method for forming holes or grooves, the only suitable means for forming holes or grooves is machining using drills, cutting tools, grindstones, etc., which increases processing costs and requires complicated processing. It was difficult to process holes and grooves in the shape.

[Problems to be Solved by the Invention] The present invention overcomes the above-mentioned drawbacks, and aims to provide a method for easily manufacturing a friction material having holes or grooves of any shape at a low cost. do.

[Means for Solving the Problems] The first step of the method for manufacturing a friction material of the present invention is a step of preforming a friction material raw material consisting of a base material, a binder, and the like.

In the method for manufacturing a friction material of the present invention, the first step includes:
The method is characterized in that it is preformed by embedding a low melting point alloy member whose melting point is higher than the temperature during heat curing in the second step and lower than the temperature during post hardening in the third step.

The low melting point alloy member has a melting point within the above range and is usually made of two or more metals selected from tin, lead, bismuth, cadmium, indium, zinc, antimony, and mercury.

Further, the shape of this low melting point alloy member is made into a desired shape according to the shape of the intended hole or groove. For example, this shape can be an inverted T-shape as shown in Figure 1, a truncated cone or inverted truncated cone as shown in Figure 4, and an oblique cylinder as shown in Figure 9. The shape can be made to correspond to the hole or groove in the case.

The base material, binder material, and friction modifier that are raw materials for the friction material are selected from various commonly used materials depending on the purpose and use. Further, as for this preforming method, a conventional preforming method can be used as is.

The second step of the method for manufacturing a friction material of the present invention is a step of heating and hardening the preform formed in the above step in a mold. As this heat curing method, a conventionally used method can be used as is.

The third step of the method for manufacturing a friction material of the present invention is a step of heating and post-curing the hot molded body obtained by heating and curing in the second step.

In the method for manufacturing a friction material of the present invention, the third step includes:
When post-curing, the low melting point alloy member embedded in the first step is not poured out, thereby forming holes or grooves of arbitrary shapes in the friction material.

Resin-molded friction materials are generally manufactured by hot press molding at the optimum curing temperature of the bonding resin, and then post-curing at a temperature slightly higher than the thermoforming temperature in order to speed up curing. In the manufacturing method of the friction material of the present invention, a low melting point alloy whose melting point is higher than the thermoforming temperature and lower than the post-curing temperature is embedded in the friction surface using FIF and aged, and then the molten alloy is The melting point alloy is poured out, collected, and holes or grooves of a predetermined shape are formed in the friction material. The recovered low melting point alloy can then be used repeatedly.

Here, [forming a hole or groove of an arbitrary shape in at least *the original drawing] means forming a hole or groove in the friction surface of the friction material, or within this friction surface and this friction material. The holes or grooves may be independent, continuous, or a mixture of the two. Further, the hole may be provided on the entire surface of the friction material, or may be provided on a part thereof, and the position of the part is not particularly limited. Further, the grooves may be formed on the surface of the friction material, may be formed inside the friction material, or may be formed in parallel. In addition, when this RFI friction material is used as a ring material friction pad, the holes or grooves may be formed in one of the friction materials, or both 1! ! It may also be formed into a rubbing material. Further, in this case, in consideration of wear of the friction material, it is desirable that the groove for handling one gas be formed as close to the backing plate as possible, but it does not necessarily have to be formed in contact with the backing plate. The shape of this hole or groove may be, for example, an inverted T-shape 41 (not shown in FIG. 4), a truncated conical shape 42 or an inverted truncated conical shape 43 (not shown in FIG. 5), or the inside of the friction material shown in FIG. An oblique cylindrical shape 44 connected via a groove 45 at
It is possible to form holes or grooves with complex shapes that cannot be easily formed by machining or the like.

[Example] The present invention will be explained below with reference to Examples.

First, with solder alloy (50% tin, 50% lead),
We made 13 low-melting point alloy members consisting of cylinders with a diameter of 7 mm and a height of 7 mm. and Figures 1 and 2.
As shown in the figure, a preformed product 3 was made consisting of these 13 low melting point alloy members 1 and friction material members 2 in which the low melting point alloy members 1 were embedded at approximately equal intervals. In this preformed product 3, the low melting point alloy member 1 is embedded so that its cylindrical surface is exposed to the friction surface. Naoko's mall!
3! The shrine part 442 is composed of a phenol resin, a fiber base material, an organic additive, and an inorganic filler.

Next, the preformed product 3 was heated and cured at a temperature of 155° C. to perform thermoforming. The black crust that had formed on the friction surface during this thermoforming was polished off to expose the solder alloy.

After that, the above FJ! Post-curing was performed with the surface facing down at a maximum temperature of 250° C. to produce a friction material 5 as shown in FIG. 3.

The solder alloy is collected in a plate placed under the friction material 5,
It had completely flowed out of the friction material 5, and the cylindrical hole 4 was formed in the friction material 5.

That is, according to this embodiment, a plurality of holes 4 having a complicated cylindrical shape can be easily formed, and the solder alloy can also be recovered and reused.

Further, as shown in FIG. 7, a friction pad consisting of the AM material 5 and a plate-shaped backing plate 6 fixed to the back surface of the syA material 5 was formed. When the friction pad is applied to a disc brake to perform brake operation, even under severe control conditions, in the case of this embodiment, generated decomposed gas can be easily removed, so that the W! The FJ friction coefficient between the friction pad and the disc rotor does not increase.
Fade can be largely eliminated. That is, according to the manufacturing method according to this embodiment, it is possible to manufacture a friction material in which fade of disc brakes is largely eliminated.

[Effects of the Invention] The method for manufacturing a friction material of the present invention includes a first step of preforming a friction material raw material consisting of a base material, a binder, etc., and a second step of heating and curing this preform in a mold. and a third step of further heating and post-curing the heated and cured heated molded body. In the manufacturing method, the first step includes preforming by embedding a low melting point alloy member whose melting point is higher than the temperature during heat hardening in the second step and lower than the temperature during post hardening in the third step, and The third step is characterized in that, during post-curing, holes or grooves of arbitrary shapes are formed in the friction material by pouring out the low melting point alloy member embedded in the first step.

Therefore, according to the present method for manufacturing a friction material, machining such as drilling and grooving is not required, and it is possible to easily form holes and grooves of complex shapes, which were difficult to machine in the past.

Furthermore, the low melting point alloy member used in this manufacturing method can be used repeatedly, so it is economical.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a preformed product in which a low melting point alloy member manufactured in an example is embedded and molded. FIG. 2 is a sectional view taken along the line AA' of the preform shown in FIG. Third
The figure is a cross-sectional view of a friction material manufactured in an example. Figure 4 shows I! which has an inverted T-shaped hole! ? ! It is a ring material diagram of a rubbing material. FIG. 5 is a sectional view of another friction material having Wg-like holes. FIG. 6 is a sectional view of a friction material having holes in still another embodiment. Figure 7 shows 1M! manufactured in the example! FIG. 3 is a cross-sectional view of a friction pad made of a friction ring member and a rocking plate.

Claims (2)

[Claims] (1) A first step of preforming a friction material raw material consisting of a base material, a binder, etc., a second step of heating and curing this preform in a mold, and a heated molded product obtained by heating and curing. In the method for manufacturing a friction material, the first step includes a third step of further heating and post-curing the friction material, wherein the first step includes
A low melting point alloy member is embedded and preformed at a temperature higher than the temperature for heat curing in the step and lower than a temperature for post-curing in the third step, and the third step is performed at the time of post-curing. 1. A method for manufacturing a friction material, comprising forming holes or grooves of an arbitrary shape on at least a friction surface by pouring out a low melting point alloy member embedded in the friction material. (2) The friction material according to claim 1, wherein the low melting point alloy member is made of two or more metals selected from tin, lead, bismuth, cadmium, indium, zinc, antimony, and mercury. Production method.