JPS5877938A - Wet type friction material - Google Patents

Abstract

PURPOSE:To enable miniaturizing and lightening of a material, by a method wherein 20-60pts.wt., based on 100pts.wt. a total friction material, of metal fiber is mixed as a friction base material. CONSTITUTION:In case a total composition is 100pts.wt., 20-60pts.wt. metal fiber is mixed as a wet type friction material, 5-15pts.wt. a binder is used as a current binder in the case of a dry method, and about 10-50pts.wt. the binder in the case of a wet method. For example, a phenolic resin series novolak resin (in the case of a dry method), and resol resin (in the case of a wet method) are used as a resin component. In case the novolak resin is used, hexaethylenetetramine may be used as a hardener. The mixture ratio of the hardener is about 12-18pts.wt. based on 100pts.wt. a total binder component. Finally, 5- 30pts.wt. various metal powders are used as friction adjuster.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wet friction material 1% used in oil for automatic transmissions and the like, which enables clutch operation using a single plate.

Conventionally, wet friction materials used in oil have been made using pulp as a base material, which has been mixed with Type 4 jlI111A property improver to make paper, processed into a predetermined shape, impregnated with a binder, and dried. , preheating treatment, pressure heating treatment, single chamfering,
It is manufactured by performing post-heat treatment, etc. However, since the friction material veneer obtained in this way is paper-like with pulp as its base material, its mechanical strength is weak and the amount of wear is large.Furthermore, the work capacity when holding is small due to the rounded shape with a low coefficient of friction. It has its drawbacks. Therefore, when incorporating it into an automatic FJI machine, etc., a metal core plate processed into the same shape as the friction material veneer is used, and a wire release material T is pasted on this core metal plate to form a friction material veneer. -Multiple pieces.

Usually 2 to 6 sheets are used for one unit of f:l theft. For this reason, in automobile transmissions, 9.6 to 7 sets are required per transmission, and the friction material is required per transmission.
Requires 9.10 to 80 pieces per unit.

Not only does the cost become high, but the space required to accommodate it also increases and the weight increases.

On the other hand, from the standpoint of energy conservation, there is a demand for smaller and lighter transmissions. Conventional pulp-based friction materials cannot meet this demand.

Therefore, as a result of numerous experiments, the inventor found that a resin mold using metal fiber Imt-based material instead of pulp-based material had both a relatively high coefficient of friction and wear resistance as a wet friction material. It is a completed invention.

That is, - The wet friction material of the present invention is used in oil, - The friction material base material is metal or fiber, and the blending ratio is 20 to 60 parts by weight based on the total 1IIi gravel material 10011 It is something to do.

Here, **The base material corresponds to conventional pulp.1
IIIWA materials are used as structural materials. The metal 4mM serving as the base material is made by processing each metal into a thin female shape, and specifically, it is steel or iron fiber, copper fiber, brass fiber, stainless steel fiber, etc. These metal fibers are available on the general market! Whatever you can do is fine. The thickness of the fiber is 6 to 1.
It is preferably about 0 Oi chron. The length is not determined by ma, but from the viewpoint of workability, it is a short fiber, preferably 1 to IOg.
That's about it.

Compounding agents other than the base material include binders, *rubbing agents*, and fillers. The binder is used to integrally bind the base material and the like, and is not limited to a specific resin. Thermosetting resins, particularly phenolic resins, are most preferred for the backing material. Glue improves the coefficient of friction.

This is to stabilize the metal powder of each wire.
For example, aluminum powder, copper powder, iron powder, etc.

In addition, alumina fiber and carbon fiber.

Rubber dust, cashew dust, graphite powder, etc. Examples of fillers include metal sulfides such as barium sulfate, diatoms, clay, and the like.

The composition range of the wet friction material of the present invention is assuming that the total composition is t-100 parts (hereinafter the same), 20 to 60 parts of metal fiber,
More preferably, it is 80 to 60 parts.

The binder is used in an amount of 5 to 50 parts (5 to 15 parts in the dry method, more preferably 8 to 12 parts, and more preferably 20 to 8 parts in the wet method).

When using a novolac resin that uses both a phenol resin-based novolac resin (dry method) and a resol resin (wet method) as the resin component, it is preferable to use hexamethylenetetracone as the curing agent. The blending ratio of the curing agent is about 12 to 18 fi, assuming t-100 parts of the total binder component.

The friction modifier is 5 to aO parts, preferably 15 to aO parts.
There are 20 copies.

Other fillers account for the remainder, with an amount of 5 to 60 parts, more preferably 10 to 80 parts.

The wet friction material of the present invention can be manufactured from a mixture having the above composition by a conventionally known wet manufacturing method or dry manufacturing method. The wet manufacturing method is similar to pulp-based friction materials, in which the other ingredients except the binder are made into a slurry, which is then processed into paper, shaped, and impregnated with the binder.

This is a method of manufacturing through steps such as drying, pressure and heat treatment 1, etc. In the dry manufacturing method, a mixture having the above composition is thoroughly mixed, then pressurized in a mold to form a compacted body, and finally heated under pressure to form a molded body (molded product).

The wet friction material of the present invention has a higher coefficient of friction and excellent wear resistance than conventional friction materials.

It has characteristics such as high strength. Therefore, by employing the wet friction material of the present invention), the work capacity per unit engagement area can be increased. Furthermore, the number of veneers per set used in conventional transmissions can be reduced. Furthermore, the wet friction material of the present invention is excellent as a cone-shaped IIIkla material for a cone clutch, which has a large work capacity per unit area, rather than a single-plate-shaped scale.

Next, examples will be shown.

As a first embodiment of the present invention, steel fiber (diameter 60 microns, length gsw), io part, phenolic tree 11110
As a second embodiment of the present invention, a raw material consisting of 20 parts of friction modifier, 40 parts of inorganic filler, 60 parts of the same steel fiber, 10 parts of phenolic resin, 20 parts of friction modifier, and 20 parts of inorganic filler Composition raw materials consisting of the following were prepared respectively.

These ingredients were mixed separately in a KVJI blender for about 15 minutes.

The resulting mixture was weighed and put into a ring-shaped veneer mold, and preformed for 1 minute with a compression molding machine set at a surface pressure of 104/d. Next, this preform is subjected to a surface pressure of 6 QI
The veneer wet friction materials of the first and second examples were manufactured by pressurizing and heating molding for 1 minute using a compression molding machine set at J/d, 165″0.

Next, a metal base material for testing was bonded to each friction material T8J4 as a lining material, and the surface was then polished to give a surface finishing process to obtain a 2-layer test piece. These sample items f
A 9600G cycle friction test was conducted using a 5AIC-8 tester. 9) The single-plate type Whhg tester has lining material glued on both sides and has an inner diameter of 101n1. Outer diameter 1271! Two pieces of friction material I are rotated on the same axis with zero rotation inertia @ 2.52 Kg・α・sec' at a rotation speed of 8600 times/min, and the mating material (fixed) that engages with each lining material is rotated. Brake and stop the clutch pressing cart 818 with 9,
Its rotational energy (work amount 1786 hQ・m)
t-1m. In addition.

The operation was repeated once every 80 seconds in oil (Ford type, ATF: Type F) set at t20'' fl.

As a comparative example, the above-mentioned pulp-based lining material and asbestos-based asbestos resin mold lining material were similarly bonded to both surfaces of the metal base material, and tested using a 5AIC & 2 tester.

Figure @1 shows the relationship between the number of tests and the coefficient of dynamic friction obtained with the 5AKNa2 tester. The vertical axis in Figure 1 is dynamic **constant;
The horizontal axis is the number of tests. In the figure, reference numeral A indicates the results of the wet friction material according to the first embodiment of the present invention, and reference numeral B indicates the results of the wet friction material according to the second embodiment of the invention.

The symbol C indicates the results for the lining material based on pulp used as a comparative example, and the symbol C indicates the results for the lining material of the asbestos resin mold used as the comparative example. Also,
FIG. 2 shows the results of the amount of wear of each sample after the 5000 friction tests. The symbols on the horizontal axis in FIG. 2 indicate each lining, and are the same as the symbols in FIG. 1. Further, the vertical axis indicates the amount of wear (w).

From FIG. 1, the wet friction material of the present invention has a high friction coefficient at the beginning of the test cycle, which is the same tendency as the conventional asbestos resin mold. However, as the number of tests increases, the friction coefficient of asbestos resin molds decreases to below Ql, whereas the wet friction material of the 2nd class of the present invention has a stable friction coefficient of α18 to QIJS. Higher than conventional paper-type wet friction materials.

On the other hand, as shown in FIG. 2, the amount of wear of the wet friction material of the present invention is about αosm, which is about 1/i of that of the conventional wet friction material!
It shows excellent wear resistance.

These results revealed that the wet friction material of the present invention has both a stable and high coefficient of friction and excellent wear resistance.

[Brief explanation of drawings]

Figure 1 is a diagram showing the relationship between the number of frictional engagements and the coefficient of dynamic friction for friction materials of the four classes, and Figure 2 is the amount of wear after 5000 simple engagements of friction materials of the same four classes. FIG. Patent Applicant: Aisin Chemical Co., Ltd. Patent Applicant: Toyota Motor Corporation, Representative Patent Attorney Hiroshi Okawa

Claims (1)

[Claims] (1) Metal fiber t-
A wet-type JIk rubbing material, characterized in that it is a base material of wrinkle lines and its blending ratio is 20 to 60 parts by weight per 10G* parts of the whole horsetail rubbing material.