JPH06307546A - Seal ring - Google Patents

Abstract

PURPOSE:To prevent the occurrence of oil shortage through intervention of oil, flowing to each corner part of a seal ring, between relative members by a method wherein protrusion-form surfaces are formed on both sides from an intersection between the inner and outer peripheral surfaces in a flat shape in cross section of a seal ring and both sides toward the central parts of the two sides. CONSTITUTION:A seal ring 11 is manufactured by using synthetic resin is disposed in a groove, formed in the outer surface of a shaft, so that a gap between a shaft made of an aluminum alloy or a soft steel and a housing with which the shaft is surrounded is sealed. In this case, the seal ring 11 is provided with protrusionform surfaces 20 which are formed from intersections 15 and 16 between an outer peripheral surfaces 12 in a flap shape in cross section and two sides 13 and 14 and intersections 18 and 19 between an inner peripheral surface 17 in a flat shape in cross section and two sides 13 and 14 toward the central parts of the two sides with height of a given size A, namely, 1/10 or less of the widths of the two sides 13 and 14. In which case, the protrusion-form surface 20 is formed in an arcuate shape having a curvature (R). Further, a straight line part may be formed at a central part. The given size A is concretely set to 3-200mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin seal ring mounted on a shaft made of aluminum alloy or soft steel.

[0002]

2. Description of the Related Art In automatic transmissions, a clutch and a brake are optionally operated by hydraulic pressure, and a synthetic resin seal ring is often used to prevent leakage of the hydraulic pressure and obtain a desired shift. FIG. 4 shows an example thereof. A housing 2 made of steel or aluminum alloy is arranged around a shaft 3 made of aluminum alloy such as ADC 12 or AC 2B, and a clutch 6 is provided in the housing 2. The rotary motion of the rotary member 7 facing the free end of the shaft 3 is input to the housing 2 via the clutch 6.

A pair of spaced ring grooves 4 on the outer peripheral surface of the shaft 3,
4 are formed, and seal rings 1 and 1 made of a synthetic resin, for example, polyether ether ketone (PEEK) resin are arranged in the ring grooves 4 and 4. The hydraulic pressure for operating the clutch 6 or the brake is transmitted through the oil passage 8 in the shaft 3, the hole 9 of the housing 2 and the oil space 10 to the clutch 6
Act on.

As the conventional seal rings 1 and 1, those having a rectangular cross section or a barrel shape in the outer peripheral surface (see Japanese Utility Model Laid-Open No. 2-122274) are used. As can be seen from FIG. 4, the oil pressure in the oil passage 8 acts in the ring grooves 4 and 4, so that one side surface of the seal rings 1 and 1 is moved to the ring grooves 4 and 4.
The sealing effect is obtained together with the outer peripheral surface of the seal ring which is pressed against the wall surface of the housing and slidably contacts the inner peripheral surface of the housing 2.

[0005]

In order to reduce the weight of the automatic transmission, since the shaft 3 is made of aluminum alloy or soft steel, the hydraulic pressure applied to the seal rings 1, 1 causes the seal rings 1, 1 to move. When the seal rings 1 and 1 rotate together with the rotating housing 2 while the side surfaces are strongly pressed against the wall surfaces of the ring grooves 4 and 4, uneven wear occurs on the wall surfaces of the ring grooves 4 and 4. This uneven wear accelerates oil deterioration due to aluminum abrasion powder, and causes a pressure drop due to oil leakage from this portion, which causes a delay in clutch engagement. Therefore,
An object of the present invention is to solve the above-mentioned problems of the conventional technology.

[0006]

In order to solve the above-mentioned problems, the present invention basically provides means for providing a convex surface from the intersection of the inner and outer peripheral surfaces of the seal ring and the side surface toward the center of the side surface. To adopt.

Specifically, the present invention is a synthetic resin disposed in a ring groove provided on an outer peripheral surface of a shaft so as to form a seal between a shaft made of an aluminum alloy or soft steel and a housing surrounding the shaft. Made of a seal ring, characterized in that the seal ring has convex surfaces on both sides from the intersection of the outer peripheral surface having a flat cross section and the side surface and the inner peripheral surface having a flat cross section and the side surface toward the center of the side surface. I will provide a.

Preferably, the height of the convex surface of the side surface to the outside of the side is not more than 1/10 of the width of the side surface, and its cross section is composed of a straight portion at the center and curved portions on both sides thereof. The inner and outer peripheral surfaces of the seal ring and the side surfaces of the convex surface are connected by an arc or R. Preferably, the height of the convex surface is 3 to 200 μm.

[0009]

When the hydraulic pressure is applied to the seal ring, the oil entering the corners of the inner peripheral surface of the housing and the outer peripheral surface of the seal ring, and the wall surface of the ring groove and the corners of the inner peripheral surface of the seal ring faces the seal ring. Intervenes between parts and does not create oil shortage. Therefore, it is possible to prevent the uneven wear experienced in the conventional technique.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, intersections 15 and 16 between an outer peripheral surface 12 having a flat cross section and both side surfaces 13 and 14 having a flat cross section, an inner peripheral surface 17 having a flat cross section and both side surfaces 13 and 1 are shown.
From both intersections 18 and 19 with 4 toward the center of both sides A
A convex surface 20 having a height of a dimension (1/10 or less of the width of the side surfaces 13 and 14) is formed.

The convex surface 20 may be formed of an arc having one curvature (R). Further, a straight line portion may be formed in the central portion. Normally, in the case of a seal ring with a side width of about 2 mm used in an automatic transmission, if the A dimension is 3 μm or less, the oil does not enter well, and if it exceeds 200 μm, the amount of oil leak increases and the sealing performance deteriorates. Therefore, the A dimension should be 3 to 20.
0 μm. The convex surface 20 may be provided only on the portion that contacts the housing 2 or the wall surface of the ring groove 4. (Fig. 2
~ 4)

FIG. 5 shows an example of the seal ring 11 of the present invention.
11 shows the state of use. The oil from the oil passage 8 fills the inside of the ring grooves 4 and 4, and the hydraulic pressure is applied to the seal rings 11 and 11.
Is pressed against the wall surface of the ring groove, and the hydraulic pressure applied to the inner peripheral surface presses the outer peripheral surfaces of the seal rings 11, 11 onto the housing 2. The hydraulic pressure acting on the side surfaces of the seal rings 11, 11
Ring groove wall made by convex surface and seal ring 1
The gap between the circular arc surfaces 1 and 11 is gradually narrowed to enhance the oil retaining effect and maintain the sealing effect. Convex surface 2
When the straight line portion of 0 is provided, the sealing effect is further enhanced.

In order to confirm the effect of the above-mentioned synthetic resin seal ring, first, as a sample seal ring,
Polyether ether ketone resin (hereinafter referred to as PEEK resin) as the base material, outer diameter φ40 mm, inner diameter φ36 mm, width 2.5
A special abutting shape having two steps in mm was used, and the seal ring corners were injection-molded using a mold capable of obtaining a smooth convex surface with a curvature of 80 to 120 μm. This surface roughness is 2
μm. A conventional synthetic resin seal ring for comparison is finished by grinding so that its cross section becomes a short shape. Next, the synthetic resin seal ring of the present invention and the conventional synthetic resin seal ring manufactured as described above are attached to the ring groove 4 of the shaft 3 made of ADC-12 aluminum alloy material and STKM15A soft steel as shown in FIG. Then, the SPHE hot rolled mild steel plate is pressed into a pipe shape to produce 2 housings. Rotate the housing at 6500 rpm, apply automatic transmission oil (called ATF) from the oil inlet of 5 at a pressure of 12 kg / cm ² , control the ATF temperature to be 120 ° C, and carry out a 50-hour durability test. Carried out. The wear amount of the groove wall in sliding contact with the ring side surface of the ring groove 4 of the shaft 3 made of the ADC-12 aluminum alloy material and STKM15A soft steel is 10
Time, 20 hours, 30 hours, and 50 hours were measured. The results are shown on the left of FIG.

As is apparent from this figure, the conventional synthetic resin seal ring has a large wear amount of 260 μm even after 10 hours, and the wear amount reaches 400 μm after the completion of the 50-hour endurance. And 1/1 of conventional products
If the seal ring of the present invention is used for 6 or less, ADC-12
Can reduce groove wear of aluminum alloy material and STKM15A soft steel.

[0015]

[Effect] The seal ring according to the present invention is manufactured in the same manner as in the prior art since its side portions are only convex surfaces, and moreover, oil shortage and uneven wear of the ring groove wall surface can be effectively prevented, and oil leakage does not occur. Few. The material of the rotating shaft can reduce the wear of the ring groove part in both ADC-12 and STKM15A, and can reduce the wear in AC-3 and AC-2B, so that the rotating shaft can be made lighter and the machinability can be improved. Other aluminum materials can also be used.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a seal ring of the present invention.

FIG. 2 is a partial cross-sectional view of a seal ring according to another example of the present invention.

FIG. 3 is a partial cross-sectional view of a seal ring according to another example of the present invention.

FIG. 4 is a partial cross-sectional view of a seal ring according to another example of the present invention.

FIG. 5 is a partial cross-sectional view showing a usage state of the seal ring of the present invention.

FIG. 6 is a partial cross-sectional view showing a usage state of a seal ring of another example of the present invention.

FIG. 7 is a partial sectional view showing a usage state of a seal ring of another example of the present invention.

FIG. 8 is a partial cross-sectional view showing a usage state of a seal ring of another example of the present invention.

FIG. 9 is a graph showing test results.

FIG. 10 is a cross-sectional view showing a usage example of a seal ring.

[Explanation of symbols]

 2 Housing 3 Shaft 4 Ring groove 11 Seal ring 12 Outer peripheral surface 13, 14 Side surface 15, 16, 18, 19 Intersection point 17 Inner peripheral surface 20 Convex surface

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor, Yorinori Kumagai, 1-4-1, Chuo, Wako, Saitama Prefecture, Honda R & D Co., Ltd. (72) Inventor, Yoshihiro Katsui, 1-4-1, Chuo, Wako, Saitama No. Stock Company Honda Technical Research Institute

Claims (5)

[Claims] 1. A seal ring made of synthetic resin, which is arranged in a ring groove provided on an outer peripheral surface of a shaft so as to form a seal between a shaft made of an aluminum alloy or soft steel and a housing surrounding the shaft, A seal ring having convex surfaces on both sides from an intersection of an outer peripheral surface having a flat cross section and a side surface and an inner peripheral surface having a flat cross section and a side surface toward the center of the side surface. 2. The seal ring according to claim 1, wherein the height of the convex surface of the side surface toward the outside is 1/10 or less of the width of the side surface. 3. The seal ring according to claim 2, wherein the inner and outer peripheral surfaces and the side surface of the convex surface are connected by R. 4. The seal ring according to claim 3, wherein the height of the convex surface in the lateral direction is 3 to 200 μm from the side surface end portion toward the central convex surface of the side surface. 5. The seal ring according to claim 1, wherein the cross section of the convex surface on the side surface is composed of a straight line portion in the central portion and curved surface portions on both sides thereof.