JP4872193B2 - Seal ring - Google Patents

Description

  The present invention relates to a seal ring that seals an annular gap between two members.

Seal rings are used in automobile automatic transmissions and various hydraulic devices. As disclosed in Patent Document 1, in order to reduce rotational torque, this seal ring has a T-shaped cross section to reduce the contact width with the side wall surface of the annular groove, thereby reducing the pressure receiving area of the seal surface. ing. In addition, a separation portion is provided to facilitate the mounting operation of the seal ring. In particular, as a form of the separating portion, a special step cut is adopted in order to cope with the reduction of the leak amount and the expansion and contraction of the seal ring due to the change in the ambient temperature.

In the seal ring having a T-shaped cross section and having a separation part, the contact width of the side surface in the vicinity of the separation part is made larger than that of other parts, and the leakage amount of the sealing fluid from the separation part is reduced.
International Publication No. 03/100301 Pamphlet

  In such a conventional seal ring, the contact width is different between the vicinity of the separating portion and the other portion on the side surface, so there is a difference in surface pressure between the two. This difference in surface pressure causes a difference in wear amount, which may cause unstable contact with the groove sidewall surface and increase the leakage of the sealing fluid.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a seal ring that stabilizes the contact with the groove side wall surface and reduces the leakage amount of the sealing fluid.

In order to achieve the above object, the present invention adopts the following configuration. That is,
A first seal surface that is attached to an annular groove provided on one of the two members and contacts a surface of the other member facing the annular groove, and a side wall surface of the annular groove on the anti-sealing fluid side. A seal ring having a second sealing surface to obtain and sealing an annular gap between the two members,
Both side surfaces of the seal ring formed of a ring-shaped member constitute the second seal surface, and the side surface on the anti-sealing fluid side is configured to be sealed by contacting the side wall surface,
In the seal ring provided with the separation part separated at one place in the circumferential direction of the seal ring,
The second seal surface is configured with a recess that is in non-contact with the side wall surface on the anti-sealing fluid side and reduces the contact width of the second seal surface so that the cross-sectional shape of the seal ring is T-shaped. The escape portion to be provided is provided over the entire circumference on the groove bottom side of the annular groove,
In the vicinity of the separation portion of the second seal surface, the non-contact portion of the escape portion has a small width and a large contact width,
The seal ring is characterized in that a plurality of regions having a large contact width matching the shape in the vicinity of the separation portion are provided on the circumference of the second seal surface.

  According to the present invention, a region having a large contact width is provided in addition to the vicinity of the separation portion of the second seal surface, and the difference in wear amount between the vicinity of the separation portion and the other portions can be suppressed, The contact can be stabilized and the leakage amount of the sealing fluid can be reduced.

Embodiments will be described with reference to the drawings. FIG. 1 is a side external view of a seal ring according to an embodiment. FIG. 2 is a perspective view of the vicinity of the separation portion of the seal ring according to the embodiment. FIG. 3 is a half cross-sectional view when the seal ring according to the embodiment is mounted.

  In the present embodiment, the seal ring 1 seals an annular gap between the housing 10 provided with the shaft hole and the shaft 11 inserted into the shaft hole of the housing 10. The seal ring 1 is mounted in the annular groove 12 of the shaft 11. The seal ring 1 is made of a resin material.

  The seal ring 1 includes a first seal surface 2 that is an outer peripheral surface that seals the inner peripheral surface 13 of the shaft hole of the housing 10 facing the annular groove 12, and a side wall surface 12 a of the annular groove 12 of the shaft 11. And a second sealing surface 3 which is a side surface to be sealed. In addition, both of the two surfaces on both sides of the seal ring 1 are the second seal surfaces 3 so that the reverse mounting is possible.

  When this seal ring 1 is applied in the direction of arrow P in FIG. 3 from the sealing fluid side (O) to the anti-sealing fluid side (A) when mounted, the sealing ring 1 is anti-sealing fluid side (A). Pressed. As a result, the second seal surface 3 presses the side wall surface 12 a on the anti-sealing fluid side (A) of the annular groove 12. The first seal surface 2 presses the inner peripheral surface 13 of the shaft hole facing the annular groove 12. In this way, the first and second sealing surfaces 2 and 3 perform sealing, whereby the seal ring 1 prevents leakage of the sealing fluid to the anti-sealing fluid side (A).

  Here, the sealing fluid is, for example, lubricating oil, and refers to ATF (Automatic Transmission Fluid) when used in an automobile transmission.

  In addition, as shown in FIGS. 1 and 2, the seal ring 1 is provided with a separation portion 4 at one place in the circumferential direction. The separation unit 4 is provided for facilitating the mounting operation when the seal ring 1 is mounted.

  The separation unit 4 is a special step cut. This special step cut is a shape cut into two steps, and a step-like cut appears on both the first seal surface 2 and the second seal surface 3. With this special step cut, the amount of leakage can be reduced, and even if the seal ring 1 expands or contracts due to a change in the ambient temperature, the gap can be made not so large correspondingly.

As shown in FIG. 2, the separation part 4 of this special step cut has convex parts 41 and 43 and concave parts 42 and 44 on the outer peripheral sides of both separated tips, and one convex part 41 is the other. The concave portion 44 is fitted, and the other convex portion 43 is fitted into the concave portion 42 and is accommodated in the annular groove 12. Further, the inner peripheral side of the separation portion 4 is cut at an intermediate position between the convex portions 41 and 43 and the concave portions 42 and 44. By being thus combined, the first, both of the second seal surfaces 2, 3 is prevented from sealing surface is interrupted from the sealed fluid side (O) to the anti-seal-fluid side (A).

  In such a seal ring 1 of this embodiment, the second seal surface 3 is not in contact with the side wall surface on the anti-sealing fluid side (A), and the clearance portion 5 that reduces the contact width of the second seal surface 3. Is provided on the groove bottom side of the annular groove 12 over the entire circumference. Since the second seal surface 3 on both side surfaces of the seal ring 1 is recessed by the escape portion 5 so that the bottom side of the annular groove 12 is not in contact, the cross-sectional shape of the seal ring 1 is T-shaped as shown in FIG. Become a mold. The contact width of the second seal surface 3 indicates the width of the second seal surface 3 in the radial direction as shown in FIG.

  Thus, the escape portion 5 is formed, the contact width of the second seal surface 3 is reduced, the pressure receiving area of the second seal surface 3 is reduced, and the rotational torque is reduced.

In the present embodiment, as shown in FIGS. 1 and 2, in the vicinity of the separation portion 4 of the second seal surface 3, the width of the escape portion 5 is reduced to form a shape having a large contact width. This is formed in order to reduce the leakage amount of the sealing fluid from the separation part 4. This large contact width region is referred to as A region 6. A region having a small contact width by increasing the width of the other escape portion 5 is referred to as a B region 7. As shown in FIG. 2, the boundary position between the second seal surface 3 and the relief portion 5 is different between the A region 6 and the B region 7, and there is a step between the boundary 61 of the A region 6 and the boundary 71 of the B region 7. Has occurred.

  In the present embodiment, a plurality of regions (A region 8) having a large contact width matching the shape in the vicinity of the separation portion 4 are provided on the circumference of the second seal surface 3. Specifically, three A regions 8 equivalent to the A region 6 are further provided, and four A regions 6 and 8 are provided on the circumference of the second seal surface 3 in four equal portions. The equal number is not limited to this, and the surface pressure on the second seal surface only needs to be averaged over the circumference, and therefore may be eight (for example, about 4 to 8 even though it depends on the diameter). . This A region 8 has no separation part 4 and has a large contact width of the second seal surface 3 as in the A region 6 having the separation part 4.

  When a plurality of the A regions 6 and 8 are equally arranged in this way, the contact width does not differ only in a part, the surface pressure on the second seal surface 3 can be averaged over the circumference, and the second seal It is possible to prevent a large surface pressure difference from occurring on the surface 3. For this reason, the wear amount is also averaged on the circumference, so that there is no great difference in the wear amount, the contact with the side wall surface 12a of the annular groove 12 is stabilized, and the leak amount of the sealing fluid can be reduced.

It is a side appearance figure of a seal ring concerning an embodiment. It is a perspective view near the isolation | separation part of the seal ring which concerns on embodiment. It is a half cross-sectional view showing a mounting state of the seal ring according to the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seal ring 2 1st seal surface 3 2nd seal surface 4 Separation part 5 Escape part 6 A area | region 7 with a separation part B area | region 8 A area | region 10 without a separation part Housing 11 Shaft 12a Side wall surface 12 Annular groove 13 Inner peripheral surface 41, 43 Convex part 42, 44 Concave part 61 Boundary 71 Boundary

Claims (2)

A first seal surface that is attached to an annular groove provided on one of the two members and contacts a surface of the other member facing the annular groove, and a side wall surface of the annular groove on the anti-sealing fluid side. A seal ring having a second sealing surface to obtain and sealing an annular gap between the two members,
Both side surfaces of the seal ring formed of a ring-shaped member constitute the second seal surface, and the side surface on the anti-sealing fluid side is configured to be sealed by contacting the side wall surface,
In the seal ring provided with the separation part separated at one place in the circumferential direction of the seal ring,
The second seal surface is configured with a recess that is in non-contact with the side wall surface on the anti-sealing fluid side and reduces the contact width of the second seal surface so that the cross-sectional shape of the seal ring is T-shaped. The escape portion to be provided is provided over the entire circumference on the groove bottom side of the annular groove,
In the vicinity of the separation portion of the second seal surface, the non-contact portion of the escape portion has a small width and a large contact width,
A seal ring, wherein a plurality of regions having a large contact width matching the shape in the vicinity of the separation portion are provided on the circumference of the second seal surface.   2. The seal ring according to claim 1, wherein a region having a large contact width in the vicinity of the separation portion of the second seal surface is formed in order to reduce a leakage amount of a sealing fluid from the separation portion.

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