JPH0519730U - Sealing device - Google Patents

Abstract

(57) [Summary] [Purpose] An object of the present invention is to provide a seal capable of exhibiting extremely excellent sealing performance even when used in a place where a large shock is applied. [Structure] A ring seal body 1 having a T-shaped cross section and a pair of backup rings 2 and 2 are provided. The protrusion 4 of the seal body 1 has a substantially trapezoidal sectional shape, and the tip sliding surface 5 has a linear sectional shape. A groove 6 for lubrication is provided in the tip sliding contact surface 5 of the protrusion 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sealing device.

[0002]

[Prior Art]

 Conventionally, as shown in FIG. 3, a seal device including a pair of backup rings a and a and a ring seal body b having a T-shaped cross section has been known.

That is, the seal body b of the sealing device in this case is composed of a base portion c having a rectangular cross section and a protrusion d protruding from the base portion c, and a tip end e of the protrusion d has a semicircular cross section. It is said to have a shape. The cross-sectional shape of the backup ring a is square.

[0004]

[Problems to be solved by the device]

 Therefore, the cross-sectional area of the tip portion e protruding in the radial direction from the backup ring a cannot be made too large, and a large sealing force cannot be obtained. That is, if used in a place where a large shock is applied, fluid leakage is likely to occur. In particular, at low temperatures (winter season), volume contraction reduced the amount of crushing on the sealing surface, resulting in further fluid leakage.

Therefore, it is an object of the present invention to provide a sealing device that exhibits excellent sealing performance even when used in a place where a large shock is applied.

[0006]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, a sealing device according to the present invention comprises a ring seal main body having a T-shaped cross section, which comprises a base having a rectangular cross section and a protrusion protruding from the base, and the ring seal main body. And a pair of backup rings disposed in a pair of cutouts formed by the base and the protrusion of the seal body, wherein the protrusion of the seal body has a substantially trapezoidal cross-section and the tip slides. The cross-sectional shape of the contact surface is linear, and a groove for lubrication is provided on the tip sliding contact surface having the straight cross-section.

[0007]

[Action]

 Since the protrusion of the seal body has a substantially trapezoidal cross-section and the tip sliding contact surface has a linear cross-section, the tip of the protrusion protruding radially from the seal groove opening edge compared to the conventional one. The cross-sectional area can be made large, the amount of crushing against the sealing surface is increased, and the sealing performance is improved and stabilized. In particular, the reliability of the sealing performance at low temperatures improves. In addition, since the groove for lubrication is formed on the tip sliding contact surface, the lubrication effect is improved, and the wear of the tip sliding contact surface is reduced.

[0008]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the drawings illustrating an embodiment.

FIG. 1 shows a seal according to the present invention, which comprises a ring seal body 1 having a T-shaped cross section and a backup ring 2 having a rectangular or square cross section.

The ring seal body 1 is made of an elastic material such as rubber or plastic and has a base 3 having a rectangular cross section and a projection 4 protruding from the base 3. Has a substantially trapezoidal cross section. In other words, the cross-sectional shape of the tip sliding contact surface 5 (the outer peripheral surface in this embodiment) of the protrusion 4 is linear.

A groove 6 for lubrication is provided on the tip sliding contact surface 5. The lubricating groove 6 may be continuous in the circumferential direction or may be discontinuous. Further, in the embodiment, two concave grooves 6 and 6 are formed in the same cross section, but of course, it may be one or three or more.

Further, in FIG. 1, a cross-sectional area S of a portion indicated by dots, that is, a portion of the protrusion 4 which is crushed by the sliding contact surface M when the seal is mounted is a seal. About 5% to 10% of the total cross-sectional area of the main body 1 is set sufficiently large (compared to the conventional one in FIG. 3).

In this case, a circumferential projecting ridge 7 is provided at the center of the inner peripheral surface 3 a of the base 3 of the ring seal body 1. The protrusion 7 prevents the fluid from leaking through between the inner peripheral surface 3a and the groove bottom 10a of the concave peripheral groove 10.

Next, the backup ring 2 has a pair of notches 8 and 8 formed by the base 3 and the protrusion 4 of the seal body 1 (the notches 8 and 8 are provided along the circumferential direction). ), The radial thickness dimension A is set to be smaller than the protrusion dimension B of the protrusion 4 of the seal body 1 in the free state. That is, in the free state, the tip portion 9 of the protrusion 4 projects in the radial direction (specifically, the radial outward direction) from the outer peripheral surface 2 b of the backup ring 2. Further, the depth dimension C of the concave circumferential groove 10 in which this seal is mounted is made substantially the same as the dimension obtained by adding the radial thickness dimension D of the base 3 to the radial thickness dimension A. Further, the cross-sectional area S ₁ of the backup ring 2 is set to be smaller than the cross-sectional area S ₂ on the inner diameter side of the sliding contact surface M of the cutout portion 8. Further, a chamfered portion 11 is formed at the end of the inner peripheral surface 2a of the backup ring 2 on the side of the protrusion 4. The axial length dimension E of the base portion 3 is set smaller than the groove width dimension F of the concave circumferential groove 10.

Further, in the circumferential projecting ridge portion 7, the projecting dimension G and the axial length dimension I can be freely provided, but the axial length dimension I is defined as the tip sliding contact surface. It is preferable to set it to be substantially equal to or slightly smaller than the axial length dimension K of 5. In other words, it is desirable to set the dimension I to 25% to 50% of the groove width dimension F.

Then, when the seal configured as described above is mounted as shown in FIG. 2, the protruding portion 9 of the protruding portion 4 is crushed by the sliding contact surface M, and the circumferential protruding portion 7 is also crushed. It will be crushed by the groove bottom 10a of the concave groove 10.

In other words, the crushing amount of the substantially trapezoidal protrusion 4 is large, and the tip sliding contact surface 5 of the protrusion 4 (see the dotted portions in FIG. 1) is brought into pressure contact with the sliding contact surface M, resulting in an extremely excellent seal. It will function.

Further, since the groove for lubrication 6 is formed on the tip sliding contact surface 5, the area of contact with the sliding contact surface M is reduced, the contact surface pressure is increased, and the sealing force is increased. it can. Further, the concave groove 6 serves as a so-called oil pocket to prevent lubrication breakage, the member 12 on the concave groove 6 side and the corresponding member 13 slide smoothly, and wear of the tip sliding contact surface 5 is reduced. However, it has a long service life.

Further, in this embodiment, since the circumferential ridge 7 is formed, the ridge 7 is pressed against the groove bottom 10a, the sealing force at the groove bottom 10a is increased, and fluid leakage is prevented. it can.

Further, as is apparent from FIGS. 1 and 2, the tip portion 9 of the protrusion 4 is largely crushed in the mounted state, but this is reflected in the circumferential protrusion 7 and the protrusion 7 is removed. By elastically and strongly compressing, the protrusion 7 and the groove bottom 10a can be brought into contact with each other with a large surface pressure, and the fluid leakage from the groove bottom 10a can be surely prevented.

The present invention is not limited to the above-described embodiment, and the design can be freely changed without departing from the gist of the present invention. For example, the dimensions of the ring seal body 1 and the backup ring 2 can be freely changed. can do.

Further, the cross-sectional shape of the lubricating groove 6 of the tip sliding contact surface 5 is a short shape in the embodiment, but may be a semicircular shape or a semielliptical shape.

Furthermore, in the embodiment, the member 12 is a shaft member and the tip sliding contact surface 5 is formed on the outer peripheral side, but conversely, the member 13 is a shaft member, When the front end sliding contact surface 5 is formed on the inner peripheral surface side, that is, the base portion 3 is the outer diameter side and the protrusion 4 is the inner diameter side, it is free.

[0024]

[Effect of the device]

 Since the present invention is configured as described above, it has the following effects.

The cross-sectional area of the tip portion 9 (dotted portions in FIG. 1) of the protrusion 4 of the ring seal body 1 can be made relatively large so that the crushing amount can be large, and the volume shrinks at a low temperature (winter season). ), It is possible to exert an extremely excellent sealing function. In particular, it is suitable for sliding seals such as shock absorbers to which a large shock pressure is applied.

The lubricating groove 6 reduces the contact area with the sliding contact surface M, increases the contact surface pressure, increases the sealing force, and exhibits excellent sealing performance and seal reliability.

Since the sliding groove 5 for lubrication is provided on the tip sliding contact surface 5, the sliding groove 6 prevents the sliding groove from slipping, and the member 12 on the concave groove 6 side and a member corresponding thereto. The sliding contact with 13 is smooth, the wear of the tip sliding surface 5 is reduced, and the service life is extended.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view showing an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a mounted state.

FIG. 3 is an enlarged cross-sectional view showing a conventional example.

[Explanation of symbols]

 1 Ring seal body 2 Backup ring 3 Base 4 Projection 5 Tip sliding contact surface 6 Lubrication groove 8 Notch

Claims (1)

[Scope of utility model registration request] 1. A ring seal main body having a T-shaped cross section, the base having a rectangular cross section, and a protrusion protruding from the base.
A seal device comprising: a pair of backup rings disposed in a pair of cutouts formed by a base portion and a protrusion of the ring seal body, wherein a cross-sectional shape of the protrusion of the seal body is approximately a base. As a shape, a sealing device is characterized in that a tip sliding contact surface has a linear cross-sectional shape, and a lubricating groove is provided on the tip sliding contact surface having a linear cross section.