JPH0823373B2 - Wet multi-plate friction engagement device - Google Patents

Description

The present invention relates to a wet multi-plate friction engagement device such as a wet multi-plate clutch and a wet multi-plate brake. INDUSTRIAL APPLICABILITY The wet multi-plate friction engagement device of the present invention can be used for a device used in a continuous slip state such as a friction clutch of a transfer of a four-wheel drive vehicle.

[Prior Art] In a wet multi-plate friction engagement device, disc plates having a friction material and separate plates are alternately arranged, and the separate plates are attached to the drive shaft side via splines,
At the same time, mount the disc plate on the driven shaft side with a spline. The disc plate and the separate plate are brought into pressure contact with each other while lubricating oil is being supplied therebetween, and are engaged by the frictional force generated. In such a wet multi-plate friction engagement device, the friction coefficient is maintained at a predetermined value by the lubricating oil, and the lubricating oil absorbs and carries a part of the friction heat to cool the friction surface. . Therefore, it is desirable that the lubricating oil be smoothly supplied to the friction surface. Therefore, Japanese Patent Application No. Sho 60-173756 and Japanese Unexamined Patent Publication No. Sho 58-77
No. 935 and the like disclose a device in which a groove is provided on the surface of the friction material and the lubricating oil is supplied from the groove. In addition, JP 59-
Japanese Patent No. 54825 discloses a device in which a separate plate is provided with through holes in the radial direction, and lubricating oil is supplied from the through holes. Further, Japanese Utility Model Laid-Open No. 62-54331 discloses an apparatus having a disc plate having through holes opened on the surface of a friction material.

[Problems to be Solved by the Invention] In the above-described conventional engagement device, although the effect of increasing the cooling capacity and improving the heat resistance can be seen, the cuts of the grooves and holes provided on the surface of the friction material are fluffed. Standing may occur, which may accelerate burns or induce lining peeling. Further, in the device in which the separate plate is provided with the through holes in the radial direction, the cooling efficiency of the separate plate is improved, but the supply of the lubricating oil to the friction surface is not sufficient.

The present invention has been made in view of such circumstances, and an object thereof is to improve the structure of the separate plate to more smoothly supply the lubricating oil from the separate plate to the friction surface.

[Means for Solving the Problems] A wet multi-plate friction engagement device according to the present invention comprises a plurality of annular disc plates having friction materials on both front and back surfaces, and a plurality of disc plates alternately arranged at coaxial positions with the disc plates. In a wet multi-plate friction engagement device that has an annular separate plate and engages the disc plate and the separate plate via lubricating oil, the separate plate has an inner peripheral surface and at least a friction surface that slides with the friction material. And a lubricating oil is supplied to the friction surface from the inner peripheral side of the separate plate through the chain holes. To do.

The disk plate is usually formed in an annular shape from a metal plate,
Has friction material on both front and back surfaces. This friction material is a paper-like member made of pulp and an inorganic filler as a friction property improving material, or a paper-like member impregnated with a thermosetting resin such as a melamine resin, a phenol resin or a modified resin, and then cured. Used materials are used. For example, a thin sheet of paper is extracted, wound on a roll machine, and heated under pressure to remove water. After that, for example, a melamine-modified phenolic resin or the like is impregnated and cured, and punched into a predetermined shape to obtain a friction material.

In addition, in order to hold the friction material on the disk, it is possible to hold the friction material by heating and pressurizing with an adhesive and bonding.

A feature of the present invention is that at least a portion of the separate plate that slides on the friction material is formed of a porous body having chain holes. By configuring in this way,
The lubricating oil can be smoothly supplied from the separate plate to the friction surface through the chain holes.

This porous body may be any porous material having chain pores, such as a foam metal having a spongy structure, a sintered metal obtained from metal powder as a raw material, and a sintered metal fiber formed into a felt shape and sintered. It can be formed from metal, porous ceramics, porous carbon material, or the like.

The porous body is provided on at least a portion of the separate plate that slides on the friction material. It may be partially provided, or the entire separate plate may be a porous body. The size of the chain hole depends on the viscosity of the lubricating oil, but if it is too small, the flow rate of the lubricating oil will decrease, resulting in poor lubricity and cooling performance. Is reduced. Preferably 10-500μ
m.

[Operation and Effect of the Invention] In the wet multi-plate friction engagement device of the present invention, at least a portion of the separate plate that slides on the friction material is formed of a porous body having chain holes. Therefore, when the disc plate and the separate plate are engaged with each other, the lubricating oil held in the chain holes is smoothly replenished to the friction surface to generate an oil film. At the same time, since the lubricating oil is constantly supplied from the inner peripheral surface of the separate plate into the chain holes, stick-slip or the like can be prevented without causing the oil film to run out. Further, the frictional surface is always cooled, and at the same time, the thermal deterioration of the friction material is prevented by the synergistic effect of cooling the separate plate.

Therefore, according to the wet multi-plate friction engagement device of the present invention, the amount of lubricating oil on the friction surface is constant, and the friction characteristics are stable. When applied to a transfer friction clutch or the like of a four-wheel drive vehicle, stick-slip is prevented and a vehicle with a comfortable ride can be provided. Further, since the lubricating oil is smoothly supplied to the friction surface, the cooling capacity is large, the thermal deterioration of the friction material can be prevented, and good friction characteristics can be maintained for a long period of time, and the durability is excellent. Further, the porous body can reduce the weight as compared with the conventional one.

[Examples] Specific examples will be described below.

In this embodiment, the present invention is applied to a friction clutch for a transfer of a four-wheel drive vehicle.

As shown in FIG. 1, the wet multi-plate friction engagement device of the present embodiment includes a plurality of separate plates 1 mounted by spline engagement with a driving side rotating body 100 and a spline engagement with a driven side rotating body 200. The separate plates 1 and the disc plates 2 are alternately arranged. The disc plate 2 has an annular shape, and annular paper-like friction materials 3 are adhered to both front and back surfaces.

2 and 3 show a front view and a sectional view of the separate plate 1, and FIG. 4 shows an enlarged sectional view of a main part of FIG.
The separate plate 1 has an annular shape with spline teeth 10 on the outer peripheral portion, and is entirely formed of iron-based foam metal. That is, the whole constitutes the porous body 12. A large number of holes having a hole diameter of 10 to 500 μm exist inside the separate plate 1, and a plurality of holes communicate with each other to form a chain hole 15.

In the wet multi-plate friction engagement device of the present embodiment having such a separate plate 1, when the disc plate 2 and the separate plate 1 are brought into pressure contact with each other by a pressing means such as a piston, the rotation of the drive-side rotating body 100 is separated. It is transmitted to the friction material 3 and the disc plate 2 via 1, and the driven side rotating body 200 rotates. At this time, the lubricating oil is supplied to the friction surface from the inner peripheral surface 11 side of the separate plate 1 through the chain holes 15. Therefore, the amount of lubricating oil on the friction surface is always constant, the coefficient of friction is stable, stick-slip is prevented, and the friction surface is cooled. Further, the lubricating oil passes through the chain holes 15 that connect the inner peripheral side and the outer peripheral side of the separate plate 1, whereby the separate plate 1 is cooled, and thermal deterioration of the friction material 3 is prevented in combination with the cooling of the friction surface. As a result, long-term stable friction characteristics can be obtained.

In this embodiment, the whole of the separate plate 1 is made of the porous body, but it is also possible to form only the portion in contact with the friction material 3 from the porous body 12 as shown in FIG. By doing so, the strength of the spline teeth 10 can be improved as compared with the case where the whole is made of a porous body, and the chain holes 15 are closed on the outer peripheral side of the separate plate 1, so that from the inner peripheral side. Most of the lubricating oil that has entered the chain holes 15 is supplied to the friction surface. Therefore, the amount of oil supplied to the friction surface increases, and more stable friction characteristics can be obtained even at high speed rotation.

[Brief description of drawings]

The drawings relate to a wet multi-plate friction engagement device according to an embodiment of the present invention. FIG. 1 is a structural explanatory view thereof, FIG. 2 is a plan view of a separator plate, and FIG. 3 is a sectional view taken along line AA of FIG. FIG. 4 is an enlarged cross-sectional view of a main part of FIG. 1, and FIG. 5 is a cross-sectional view of a separate plate of another aspect. 1 ... Separate plate 2 ... Disc plate 3 ... Friction material, 10 ... Spline tooth 12 ... Porous body, 15 ... Chain hole

Claims (1)

[Claims] 1. A plurality of annular disc plates having friction materials on both front and back surfaces, and a plurality of annular separate plates alternately arranged at coaxial positions with the disc plates, the disc plates and the separate plates. In a wet multi-plate friction engagement device for engaging a plate with a lubricating oil, the separate plate is opened at an inner peripheral surface and at least a friction surface sliding on the friction material, and the inner peripheral surface and the friction Wet multi-plate friction comprising a porous body having a chain hole communicating with the surface, and the lubricating oil is supplied to the friction surface from the inner peripheral side of the separate plate through the chain hole. Engagement device.