JPH06213322A - Seal ring for hydraulic apparatus - Google Patents

Abstract

PURPOSE:To lessen oil leak at a hydraulic apparatus by improving the shape of an abutment with a hooked step for use in a seal ring for the hydraulic apparatus. CONSTITUTION:One abutment part of a seal ring 21 is formed with an L-form angle part 26 opening to the upper and lower side faces 22, 23, end face 25, and peripheral surface 24 and a groove part 27 opening to the peripheral surface 24, upper side face 22, and L-form angle part 26, while a projecting piece 34 on the other abutment part is detained with the L-form angle part 26 and groove 27, and small gaps C1, C2, C3 are formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal ring used for hydraulic equipment.

[0002]

2. Description of the Related Art A seal ring is often used as a rotating or reciprocating member used in a hydraulic device such as an automatic transmission of an automobile or a torque flow type transmission of a construction machine. This seal ring is required not only to have the function of minimizing leakage of hydraulic pressure, but also to have characteristics such as small self-wear, small material change over time, durability at high temperature, and durability at high pressure. It

The seal ring proposed to satisfy the above characteristics has the structure shown in FIGS. One of the mating portions of the seal ring 1 has an L-shaped groove 5 which is open to the lower portions of the inner and outer peripheral surfaces 2, 6, the lower side surface 3 and the end surface 4 and extends in the radial direction. The other abutment portion has an inverted L-shaped groove 8 which is open to the upper side surface 7, the inner and outer peripheral surfaces 2, 6 and the upper portion of the end surface 4'and extends in the radial direction.

FIG. 6 shows the assembled state of the abutment portion. The upward projecting piece 9 is inserted into the L-shaped groove 5 and the downward projecting piece 10 is inserted into the reverse L-shaped groove 8 to form a key-shaped stepped joint. As a result, a gap 11 around the end face 4 and a gap 12 around the end face 4'are created.

[0005]

The gaps 11 and 12 are
Since they are in communication with each other through the inner peripheral side thereof, for example, the hydraulic pressure that enters the inner peripheral side of the ring groove from the lower side surface 3 through the gap 12 pushes the seal ring radially outward, At the same time, it leaks to the upper side 7 through the gap 11. The gaps 11 and 12 are larger than expected due to manufacturing and assembling errors of the case and the ring, so that a large amount of oil leaks. When the amount of oil leakage increases, the capacity of the oil supply pump must be increased in order to maintain the required hydraulic pressure. Therefore, it is an object of the present invention to solve the above-mentioned problems of the conventional technology.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention replaces a conventional groove that penetrates in the radial direction with a groove portion that is opened only on the inner or outer circumference and is opened on the end face. adopt.

In the present invention, specifically, an L-shaped corner portion in which one abutment portion is cut off into an L-shaped portion including upper and lower side surfaces, an outer peripheral surface and an end surface, and an upper side surface, an outer peripheral surface and an L-shaped corner portion. A seal ring for a hydraulic device, characterized in that the seal part has a groove part of which is open, and the other mating part has a side surface and a bottom surface of the groove part and a projecting piece that contacts the side surface of the L-shaped corner part. I will provide a.

Preferably, a step portion is provided between the projecting piece and the lower side surface, and the step portion faces the end surface of the L-shaped corner portion.

[0009]

[Function] For example, the hydraulic pressure entering from the gap on the lower side is
The oil does not leak directly to the inner peripheral side, but escapes to the inner peripheral side through the zigzag passage formed by the groove and the projecting piece, that is, the oil leaks through a small passage, so the oil leakage is extremely small.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An example of the present invention will be described with reference to FIGS. One of the mating portions of the seal ring 21 is the upper and lower side surfaces 2
2, 23, the outer peripheral surface 24 and the end surface 25, and an L-shaped corner portion 26 in which a portion including an intersection between the outer peripheral surface and the end surface is vertically cut off in an L shape, the outer peripheral surface 24, the L-shaped corner portion 26, The upper side surface 22 has a groove 27 that is partially open. The groove portion 27 has a bottom surface 28, a lateral surface 29, and a side surface 30. The groove portion 27 and the L-shaped corner portion 26 form a protrusion 31, and the side surface 32 of the protrusion 31 is located radially inward of the outer peripheral surface 24.

The other mating portion of the seal ring 21 has an L-shaped protrusion 34 having a step 33. An inward groove 37 is provided between the radially inwardly projecting portion 35 of the projecting piece 34 and the end surface 36.
make.

FIG. 2 shows a state where the seal ring fitting portion is mounted. The protrusion 25 is inserted into the groove 27, and the protrusion 31 is inserted into the groove 37. The protrusion 34 is seated on the bottom surface 28 of the groove 27. As a result, the gap between the protrusion 34 and the bottom surface 28 (C
₁ ), the gap (C ₂ ) between the protrusion 35 and the side surface 30 and the gap (C ₃ ) between the side surface 32 and the groove 37 are formed in a zigzag shape and can be made small. .

The first gap 38 is opened to the outer periphery and the lower side, the second gap 39 is opened to the outer periphery and the upper side, and the third gap 40 is opened to the inner periphery and the upper and lower sides. These gaps 38, 39, 40 have small gaps (C ₁ , C ₂ , C ₃ ).
Since the communication is restricted by, the oil flow is considerably restricted, and the oil leakage is extremely small.

Using the test apparatus shown in FIG. 3, the performance of an example of the present invention and a conventional seal ring was confirmed. Rotating shaft 1
The shaft 102 with a ring groove is inserted into the cylindrical portion 101 at the end of 00. High-pressure oil is introduced (IN) and discharged (OUT) between the pair of ring grooves. Seal ring 1
The oil leaked from 03 is collected in the graduated cylinder 104. The seal ring used has an outer diameter of 52φ, a width of 2.4,
The thickness is 2.4 mm, and as an example of the present invention, the shape shown in FIGS. 1 and 2 (C ₁ = 0.09 mm, C ₂
= 0.1 mm, C ₃ = 0.3 mm) and the conventional example (head clearance: 0.
25 mm) having the shape shown in FIGS. The rotating shaft 100 has a rotation speed of 2000 rpm and the hydraulic pressure is 18 kgf / cm.
^2. Oil is ATF.

The test results are shown in FIG. The seal ring of the present invention had no difference in sealing property between front and back.

[0016]

[Effect] The use of the specially shaped key-shaped stepped joint as in the present invention can reduce the amount of oil leakage to 1/3 or less of the conventional amount.

[Brief description of drawings]

FIG. 1 is a perspective view of a mating portion of a seal ring according to an example of the present invention.

FIG. 2 is a perspective view showing an assembly of an abutment portion according to an example of the present invention.

FIG. 3 is a sectional view of a test apparatus.

FIG. 4 is a graph showing an oil leak test result.

FIG. 5 is a perspective view of a mating portion of a conventional seal ring.

FIG. 6 is a perspective view showing an assembly of a conventional seal ring abutment portion.

[Explanation of symbols]

21 Seal Rings 22 and 23 Upper and Lower Side Surfaces 24 Outer Surface 25 End Faces 26 L-Shaped Corners 27 Grooves 31 Projections 34 Projections 35 Projections 37 Grooves C ₁ , C ₂ , C ₃ Gap

Claims (2)

[Claims] 1. An L-shaped corner portion in which one abutment portion is cut off into an L-shaped portion including upper and lower side surfaces, an outer peripheral surface and an end surface,
The outer peripheral surface and the L-shaped corner portion are formed with a groove portion partially open, and the other joint portion has a side surface and a bottom surface of the groove portion and the L
A seal ring for hydraulic equipment, which has a projecting piece that is in contact with a side surface of a square portion. 2. A step portion is provided between the protrusion and the lower surface,
The seal ring for hydraulic equipment according to claim 1, wherein the stepped portion faces an end surface of the L-shaped corner portion.