JPH1163056A - Wet friction material and manufacture of wet friction plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve wear resistance and to stabilize a friction factor by burning an organic fiber beforehand to a specified temperature in an oxygen free atmosphere before blending the organic fiber with the other constituting material of a paper material main body for sheeting in a disk material for a friction clutch. SOLUTION: Before blending an organic fiber with the other constituting material of a paper base body for sheeting, the organic fiber is burned at about 300 to 600 deg.C in an oxygen free atmosphere beforehand by using a heating furnace. This is blended with an inorganic fiber and organic and inorganic fillers as raw materials for the paper base body. The paper base body is dipped in phenol thermosetting synthetic resin solution, then this is heated or naturally dried to be hardened so as to manufacture a friction material 2, and then by punching the friction material 2 or the like to form the same in a specified shape and polymer-bonding (adhering) it to both surfaces of a core metal 1, a clutch disk D is obtained. Thus, the opposing requests of wear resistance and a stable friction characteristic are satisfied, and initial conformability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet friction plate such as a clutch disk for a friction clutch and a wet friction material provided on the friction plate.

[0002]

2. Description of the Related Art Conventionally, a paper base is formed by mixing various fibers and fillers and performing a usual paper making operation, and the paper base is impregnated with a synthetic resin to produce a wet friction material. A method and a method of obtaining a wet friction plate by punching a friction material manufactured as described above into a predetermined shape and polymerizing and adhering it to a core metal are already known (for example, see Japanese Patent Application Laid-Open No. 62-16113). .

[0003]

In the wet friction material and friction plate manufactured by the above-mentioned conventional method, there is a disadvantage that the friction coefficient becomes unstable when the wear resistance of the friction material is improved. On the contrary, there is a disadvantage that the wear resistance is lowered when the friction coefficient is stabilized. That is, it has been difficult to simultaneously improve the abrasion resistance and stabilize the friction characteristics (friction coefficient) by the conventional wet friction material / friction plate manufacturing method.

[0004] The present invention has been made in view of such circumstances, and can simultaneously satisfy the above contradictory requirements of the conventional method, and has a good initial conformability, and a method of manufacturing a wet friction plate and a wet friction plate. It is intended to provide.

[0005]

Means for Solving the Problems To achieve the above object, the invention of claim 1 is a method for producing a wet friction material in which a paper substrate containing an organic fiber is formed, and the paper substrate is impregnated with a synthetic resin and cured. Before compounding the organic fibers with the other constituent materials of the paper substrate for the papermaking, the organic fibers are subjected to a temperature of 300 to 600 ° C. in a non-oxidizing atmosphere.
Characterized by firing in advance. According to this feature,
In the composition of the friction material, the organic fiber having a high volume ratio and a low heat resistance is subjected to the above-mentioned baking treatment before it is blended with other constituent materials of the paper base, thereby causing a dehydration / dehydrogenation reaction. By causing a cyclization condensation reaction, heat resistance is improved. For this reason, by impregnating and curing a synthetic resin on a paper substrate formed using such organic fibers, a wet friction material having excellent abrasion resistance and stable friction characteristics can be obtained. The initial conformability of the material is also good.

According to a second aspect of the present invention, there is provided a method for producing a wet friction material in which a paper substrate containing organic fibers is formed and the paper substrate is impregnated and cured with a synthetic resin. The obtained friction material is fired at 300 to 600 ° C. in a non-oxidizing atmosphere. According to this feature, the friction material containing an organic fiber having a high volume ratio and a low heat resistance is subjected to the above-described baking treatment, whereby the organic fiber causes a dehydration / dehydrogenation reaction to cause a cyclization condensation reaction. Heat resistance can be exhibited, and therefore, a wet friction material having excellent wear resistance and stable friction characteristics can be obtained, and the initial adaptability of the friction material is also improved.

A third aspect of the present invention is a method for producing a wet friction plate, comprising: forming a paper substrate containing an organic fiber; and impregnating and hardening the paper substrate with a synthetic resin to fix a friction material to a cored bar. After fixing the friction material to the core metal,
300-600 ° in a non-oxidizing atmosphere
It is characterized by firing with C. According to this feature, the friction material containing the organic fiber having a high volume ratio and a low heat resistance is subjected to the above-mentioned baking treatment on the core metal, whereby the organic fiber causes a dehydration / dehydrogenation reaction to cause a cyclization condensation reaction. As a result, good heat resistance can be exhibited, and therefore, a wet friction plate having excellent wear resistance and stable friction characteristics can be obtained, and at the same time, the initial adaptability of the friction material is also good. It becomes something.

In each of the first to third aspects of the present invention, if the sintering temperature is lower than 300 ° C., the sintering of the organic fibers is insufficient and the desired effect cannot be expected. If it exceeds, the firing is excessive and the strength of the friction material deteriorates, so the firing temperature is set to 300 to 600 ° C.

A fourth aspect of the present invention relates to a method for producing a wet friction plate in which a paper substrate containing organic fibers is formed, and a friction material obtained by impregnating and curing the paper substrate with a synthetic resin is fixed to a cored bar. After the friction material is fixed to the metal core, the friction material is fired at 100 to 600 ° C. in a non-oxidizing atmosphere by a high-frequency heating device. According to this feature, the friction material containing the organic fiber having a high volume ratio and a low heat resistance is subjected to the above-mentioned baking treatment by high-frequency heating on a cored bar, whereby the organic fiber undergoes a dehydration / dehydrogenation reaction to form a cyclocondensation. By causing the reaction, good heat resistance can be exhibited, and therefore, a wet friction plate having excellent abrasion resistance and stable friction characteristics can be obtained, and at the same time, the friction material can be initially adapted. The aggressiveness is also improved, and the opponent's aggressiveness can be further reduced.

In the invention of claim 4, if the firing temperature is lower than 100 ° C., the firing by the high frequency heating of the organic fibers is not sufficient, and the desired effect cannot be expected, and the firing temperature cannot exceed 600 ° C. If firing is excessive, the strength of the friction material is degraded.
° C.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below based on embodiments of the present invention illustrated in the accompanying drawings.

FIG. 1 is an overall perspective view showing an embodiment of a clutch disk, and FIG. 2 is a view 2-2 of FIG.
3 to 6 are graphs comparing the measurement results of the friction characteristics and the wear amount between the examples and the comparative examples.

First, in FIGS. 1 and 2, a clutch disc D for a wet multi-plate friction clutch as a wet friction plate obtained by the present invention is annularly bonded to a metal core 1 and both surfaces of the metal core 1 are polymerized and bonded. Ring-shaped wet friction material 2
A plurality of radially extending oil grooves 2a are formed on the surface of each friction material 2.
Are formed at intervals in the circumferential direction.

Next, the manufacturing process of the clutch disc D will be described. The process is performed by mixing various fibers and fillers and forming the mixture by a conventionally known wet papermaking method (ie, ordinary papermaking operation).
Forming a paper substrate by the method described above, impregnating the paper substrate with a synthetic resin, and then curing to obtain a wet friction material 2. The obtained friction material 2 is formed into a predetermined shape to form a core metal 1. And a step of polymerizing and fixing to both surfaces. In this case, the composition of the wet friction material 2 includes, for example, organic fibers such as pulp and aramid fibers, inorganic fibers such as glass fibers and carbon fibers, organic fillers such as cashew dust, and inorganic fillers such as diatomaceous earth. And a synthetic resin such as a phenol resin.

In the production of the clutch disk D, for example, first, the above-mentioned organic fiber, inorganic fiber, organic filler and inorganic filler which are the raw materials of the paper base are mixed, and this is mixed with a conventionally known wet papermaking method (ie, Papermaking is performed by ordinary papermaking work) to produce a paper substrate. The paper substrate is impregnated with a phenolic thermosetting synthetic resin liquid, and then cured by heating or air drying to produce a friction material 2 and punching out the friction material 2 into a predetermined shape. The clutch disk D is obtained by molding and polymerizing and fixing (adhering) to both surfaces of the cored bar 1.
Instead of fixing the cured friction material 2 to the metal core 1 as described above, an uncured relatively soft friction material intermediate is superimposed on the metal core 1 and pressed by a pressing die or the like. May be completely cured (accordingly, fixed to the core metal 1).

Although the above is basically the same as the conventionally known method of manufacturing a clutch disk, in the present invention, in particular, before mixing the organic fiber and other constituent materials of the paper base for papermaking, a heating furnace is used. The friction material obtained by pre-firing the organic fiber at 300 to 600 ° C. in a non-oxidizing atmosphere by using (corresponding to Example 1 described later), or by impregnating and curing a paper substrate with a synthetic resin, After sintering at 300 to 600 ° C. in a non-oxidizing atmosphere using a heating furnace (also corresponding to Example 2), or after fixing the friction material 2 to the metal core 1, the clutch disk D is removed from the heating furnace. Baked at 300 to 600 ° C. in a non-oxidizing atmosphere (also corresponding to Example 3), or the friction material 2 is
Then, the clutch disk D is fired at 100 to 600 ° C. by a high-frequency heating device in a non-oxidizing atmosphere using a high-frequency heater (also corresponding to Example 4).

Next, a specific embodiment of the present invention will be described. In this example, a friction material having the composition shown in the following composition table was formed by a conventional method (that is, by mixing various fibers and fillers, forming a paper substrate by a normal paper-making operation, and then synthesizing the paper substrate. The resin is impregnated and cured).

[0018]

[Table 1]

Example 1 In this example, the organic fibers in the above composition table were baked independently at 400 ° C. for 30 minutes in a non-oxidizing atmosphere using a heating furnace, and the fired organic fibers were used. Thus, a new friction material was obtained by the same manufacturing method as in the prior art. [Example 2] In this example, a friction material having the composition shown in the above composition table was manufactured by the same manufacturing method as the conventional method, and then fired at 400 ° C for 30 minutes in a non-oxidizing atmosphere using a heating furnace to obtain a new friction material. I got [Example 3] In this example, a friction material having the composition shown in the above composition table was manufactured by the same manufacturing method as that of the related art, and then the friction material was punched into a predetermined shape and fixed to both surfaces of a metal core to manufacture a friction plate. After that, 40 minutes in a non-oxidizing atmosphere by a heating furnace.
It was baked at 0 ° C. for 30 minutes to obtain a new friction plate. [Example 4] In this example, a friction material having the composition shown in the above composition table was manufactured by the same manufacturing method as that of the related art, and then the friction material was punched into a predetermined shape and fixed to both surfaces of a metal core to manufacture a friction plate. Then, it was baked at 400 ° C. for 30 minutes in a non-oxidizing atmosphere by a high frequency heater to obtain a new friction plate.

As a comparative example, a friction material having the composition shown in the above composition table was manufactured by the same manufacturing method as in the prior art. However, in this comparative example, the firing treatment was not performed on the organic fiber or the friction material (friction plate).

FIGS. 3 to 6 are graphs showing the measurement results of the friction coefficient and the amount of wear of the clutch disks according to each of the above embodiments and comparative examples. In these drawings, in particular, (a)
The graph of shows the measurement test results of friction coefficient by wet clutch dynamometer performed on each clutch disk, the horizontal axis is the number of clutch disconnection,
The vertical axis is the coefficient of friction. In measuring the friction coefficient, for example, a clutch disk is mounted on an inertial clutch full-size tester, and an inertial body (flywheel) of the tester is rotated at a predetermined rotation speed. Intermittently stop the measurement. The measurement conditions in this embodiment are as follows: the input rotation speed of the inertial body is 3000 rpm, the inertial mass of the rotating system including the inertial body is 0.015 kgmS ² , the pressing load is 408 kgf, the oil temperature is 100 ° C., and the oil (ATF) Is DexronII.

As is clear from the graph of FIG. 2A, the coefficient of friction of the friction material according to the conventional example (comparative example) changes relatively sharply at the beginning of the measurement (that is, when the number of clutch engagements / disconnections is small). Are seen (thus poor initial familiarity),
After that, the friction coefficient gradually decreased, whereas the friction coefficient of the friction material according to the present invention (each embodiment) was substantially constant without being largely affected by the number of times of clutch engagement / disconnection. With such a friction material, the friction coefficient is relatively stable irrespective of the number of times of clutch engagement / disconnection, and since there is no sudden increase and change especially at the beginning of the measurement, it can be seen that the initial conformability of the friction surface is good. In addition, the reason that the initial conformability becomes good is that the heat resistance is improved by removing in advance the products of thermal decomposition that occurs when using the friction material by firing organic fibers,
It is also considered that the organic fibers themselves are less likely to be decomposed due to cyclization condensation due to dehydration and dehydrogenation reactions during the firing of the organic fibers, thereby improving heat resistance.

Further, as also shown in FIG. 6, in the friction material according to the conventional example (comparative example), some abnormalities such as burns and heat spots occurred in the mating material as the number of clutch engagements increased. In the friction material, no abnormality was found in the mating material, and it can be seen from this point that the friction material according to the fourth embodiment had a lower mating aggressiveness than the conventional example. The reason that the friction material according to Example 4 reduced the opponent aggressiveness was that the surface temperature of the friction material was too high when heating to the required level up to the center of the friction material in the heating furnace, and The part may be overheated and the hardness may be too high, and the aggressiveness of the opponent tends to increase. However, with high frequency heating, the friction material can be uniformly heated to the center while avoiding overheating, so the surface temperature ( Therefore, the surface hardness does not become too high, and the opponent aggressiveness can be weakened.

The graphs in FIGS. 3 to 6B are graphs showing the measurement results of the wear amount. In measuring the amount of wear, for example, a clutch disk is mounted on an inertial clutch full-size tester, and an inertial body (flywheel) of the tester is rotated at a predetermined rotation speed. Stop by intermittent and measure. The measurement conditions in this embodiment are as follows: the input rotation speed of the inertial body is 2600 rpm, the inertial mass of the rotating system including the inertial body is 0.085 kgmS ² , and the pressing load is 610 kg.
f, the oil temperature is 100 ° C., and the oil (ATF) is Dexron II.

As is clear from the graph of FIG. 2B, the wear amount of the friction material according to the present invention (each embodiment) is clearly smaller than the wear amount of the friction material according to the conventional example (comparative example). You can see that.

[0026]

As described above, according to the first and second aspects of the present invention, conflicting requirements such as improvement of abrasion resistance and stabilization of friction characteristics (friction coefficient) can be satisfied at the same time. , A high-quality wet friction material having a good value is obtained.

According to the third aspect of the present invention, conflicting demands such as improvement of abrasion resistance and stabilization of friction characteristics (friction coefficient) can be satisfied at the same time, and a high quality material having good initial conformability can be obtained. A wet friction plate is obtained.

Further, the invention of claim 4 can simultaneously satisfy conflicting demands such as improvement of wear resistance and stabilization of friction characteristics (friction coefficient), and also have good initial adaptability and aggressiveness to a partner. And a high-quality wet friction plate with reduced friction is obtained.

[Brief description of the drawings]

FIG. 1 is an overall perspective view showing an embodiment of a clutch disk.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a graph comparing the measurement results of friction characteristics and abrasion loss between Example 1 and Comparative Example.

FIG. 4 is a graph comparing the measurement results of the friction characteristics and the wear amount between Example 2 and Comparative Example.

FIG. 5 is a graph comparing the measurement results of friction characteristics and abrasion loss between Example 3 and Comparative Example.

FIG. 6 is a graph comparing the measurement results of the friction characteristics and wear amount between Example 4 and Comparative Example.

[Explanation of symbols]

 D: clutch disk as friction plate 1: core metal 2: friction material

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobuyuki Katayama FCC Research Institute, 46, at 7000 Nakagawa, Hosoe-cho, Husa-gun, Shizuoka Prefecture Inside of FCC Technology Research Laboratories, 46 shares at 7000

Claims (4)

[Claims] 1. A paper substrate containing an organic fiber is formed,
In the method for producing a wet friction material in which the paper substrate is impregnated with a synthetic resin and cured, the organic fibers are mixed in a non-oxidizing atmosphere for 300 minutes before the organic fibers and other constituent materials of the paper substrate are mixed for the papermaking. A method for producing a wet friction material, wherein the method is preliminarily baked at a temperature of up to 600 ° C. 2. A paper substrate containing an organic fiber is formed,
A method for producing a wet friction material in which a paper substrate is impregnated and cured with a synthetic resin, wherein the friction material obtained by impregnating and curing the paper substrate with a synthetic resin is fired at 300 to 600 ° C in a non-oxidizing atmosphere. Method for producing a wet friction material. 3. A paper substrate containing an organic fiber is formed,
In a method of manufacturing a wet friction plate in which a friction material obtained by impregnating and curing a synthetic resin on a paper substrate is fixed to a metal core, after fixing the friction material to the metal core, the friction material is placed in a non-oxidizing atmosphere. A method for producing a wet friction plate, comprising firing at 300 to 600 ° C. 4. A paper substrate comprising an organic fiber is formed,
In a method of manufacturing a wet friction plate in which a friction material obtained by impregnating and curing a synthetic resin on a paper substrate is fixed to a metal core, after fixing the friction material to the metal core, the friction material is placed in a non-oxidizing atmosphere. 100-600 by high frequency heating device
A method for producing a wet friction plate, characterized by firing at a temperature of ° C.