JPH0726603Y2 - Reciprocating sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a reciprocating sealing device, and particularly to prevent leakage of a sealing fluid from a reciprocating portion of two members that relatively move in the axial direction. The present invention relates to a reciprocating sealing device.

[Conventional technology]

2. Description of the Related Art Conventionally, reciprocating sealing devices that prevent leakage of sealing fluid such as oil have been widely used in reciprocating mechanisms such as shock absorbers used in automobiles, motorcycles, various machines, and the like.

FIG. 4 shows a conventional reciprocating sealing device. A metallic reinforcing ring 1 having an L-shaped cross section is provided with an elastic body such as rubber so as to cover the lower part of the reinforcing ring 1. A seal lip 2 composed of is integrally fixed. An outer peripheral surface 3 located on the outer peripheral side of the reinforcing ring 1 is formed on the seal lip 2, and a lip portion 4 extending upward is formed inside the reinforcing ring 1 of the seal lip 2. A lip tip portion 5 is formed on the inner peripheral surface of the upper end portion of the lip portion 4 toward the inside. . Also, the lip portion 4
A spring 6 is mounted in a mounting groove 7 formed in the circumferential direction at a position on the outer peripheral surface corresponding to the lip tip 5.

The sealing device is arranged between a predetermined cylindrical housing 8 and a shaft 9 which is held by a bearing or the like and reciprocates with respect to the housing 8. The outer circumference of the seal lip 2 is provided on one housing 8 side. The surface 3 has the seal lip 2 on the side of the other shaft 9.
The lip tips 5 are attached so as to be in close contact with each other. Further, a spring 6 is mounted in the mounting groove 7 of the seal lip 2, and the lip tip portion 5 is tightened inward in the radial direction. Then, oil, grease or the like is interposed between the lip tip portion 5 of the seal lip 2 and the shaft 9 to slide the seal lip 2, thereby sealing the sealing fluid.

[Problems to be solved by the device]

However, in the conventional reciprocating sealing device, when the shaft 9 is normally reciprocated, the lip tip 5 of the seal lip 2 is only in contact with the shaft 9, so that the shaft 9 reciprocates smoothly. However, when the pressure of the sealing fluid becomes high, the lip portion 4 is strongly pressed in the direction of the shaft 9 by the pressure applied to the seal lip 2, the lip tip portion 5 is crushed, and the entire inner peripheral surface of the lip portion 4 is crushed. Has a problem that the shaft 9 comes into contact with the shaft 9 and the resistance against the reciprocating motion of the shaft 9 is greatly increased, so that the reciprocating motion of the shaft 9 is not smoothly performed. In addition, the increase in resistance during the reciprocating motion causes the lip portion 4 (particularly, the lip tip portion 5) of the seal lip 2 to generate heat, which causes deterioration of the lip portion 4 and significantly shortens the life. It has a problem of being invited.

The present invention has been made in view of these points, and it is possible to reduce the resistance to the shaft even when the sealing fluid has a high pressure, prevent deterioration of the seal lip, and prolong the service life. An object of the present invention is to provide a reciprocating sealing device that can be reciprocated.

[Means for Solving the Problems]

In order to achieve the above object, a reciprocating sealing device according to the present invention has a seal lip integrally fixed to an annular metal reinforcing ring, and the reciprocating member of the reciprocating member is provided inside the reinforcing ring of the seal lip on the inner peripheral surface. In a reciprocating sealing device formed by forming a lip portion in contact with an outer peripheral surface, a plurality of axially extending portions are formed on an inner peripheral surface of the lip portion and apart from the lip tip portion by a predetermined length in the axial direction. It is characterized in that a groove is formed.

[Action]

According to the present invention, first, when the tip of the lip and the shaft are brought into contact with each other, when the shaft is stopped or the pressure of the sealing fluid is low, the sealing fluid is reciprocated in the axial direction. On the other hand, when the pressure of the sealing fluid becomes high and the pressure applied to the seal lip causes the entire inner peripheral surface of the lip to come into contact with the shaft, a groove is formed on the outer peripheral surface of the shaft. Since the parts come into contact with each other, the contact area between the lip portion and the shaft can be remarkably reduced, and therefore the resistance when the shaft reciprocates can be remarkably reduced, and the friction of the lip portion can be reduced. In addition, the deterioration of the lip portion due to heat generation can be prevented and the life of the lip portion can be extended.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3 and the same parts as those in FIG.

FIG. 1 and FIG. 2 show an embodiment of the present invention. A metallic reinforcing ring 1 having an L-shaped cross section is provided with a rubber or the like so as to cover the lower part of the reinforcing ring 1. A seal lip 2 made of an elastic body is integrally fixed. An outer peripheral surface 3 located on the outer peripheral side of the reinforcing ring 1 is formed on the seal lip 2, and a lip portion 4 extending upward is formed inside the reinforcing ring 1 of the seal lip 2.
A lip tip portion 5 is formed on the inner peripheral surface of the upper end portion of the lip portion 4 toward the inside. In addition, in this embodiment, as shown in detail in FIG. 2, the inner peripheral surface of the lip portion 4 is located below the lip tip portion 5 and is axially separated from the lip portion 5 by a predetermined length. , A plurality of grooves 10 extending in the axial direction are formed in parallel at equal intervals in the circumferential direction.
Further, the lip tip portion 5 on the outer peripheral surface of the lip portion 4
In the mounting groove 7 formed in the circumferential direction at a position corresponding to
The spring 6 is attached.

Next, the operation of this embodiment will be described.

When the sealing device is mounted in this embodiment, the sealing device is arranged between the housing 8 and a shaft 9 which is held by a bearing or the like and which reciprocates in the axial direction with respect to the housing 8. The outer peripheral surface 3 is attached to the housing 8 side and the lip tip 5 is attached to the other shaft 9 side. Then, the spring 6 is mounted in the mounting groove 7 of the seal lip 2, and the lip tip portion 5 is tightened radially inward toward the shaft 9.

Then, due to the contact between the shaft 9 and the portion of the lip tip 5 where the groove 10 is not formed, the shaft 9 is stopped or the pressure of the sealing fluid is low.
Is designed to reciprocate in the axial direction to seal the sealing fluid.

Further, when the pressure of the sealing fluid becomes high, the lip portion 4 is strongly pressed in the direction of the shaft 9 due to the pressure applied to the seal lip 2, the lip tip portion 5 is crushed, and the entire inner peripheral surface of the lip portion 4 is shrunk. 9, but in this case, as shown in FIG. 2, the groove 10 is formed on the outer peripheral surface of the shaft 9.
Since the parts come into contact with each other, the lip portion 4 and the shaft 9
It is possible to significantly reduce the contact area with.

Therefore, in this embodiment, when the inner peripheral surface of the lip portion 4 contacts the shaft 9, the contact area between the lip portion 4 and the shaft 9 can be reduced by the groove 10. The resistance during reciprocal movement of 9 can be significantly reduced. As a result, even when the sealing fluid has a high pressure, the friction of the lip portion 4 can be reduced to prevent the lip portion 4 from generating heat, and deterioration due to this heat generation can be prevented to prolong the service life. .

The shape and the number of the grooves 10 provided on the inner peripheral surface of the lip portion 4 can be variously selected and determined according to the sealing conditions.

Further, FIG. 3 shows another embodiment of the present invention, in which two lip tips 5a, 5b are vertically arranged inwardly on the inner peripheral surface of the lip portion 4 of the seal lip 2. It is formed to have a space. Further, in the present embodiment, from the position on the inner peripheral surface of the lip, which is spaced downward from the upper lip tip 5a by a predetermined length in the axial direction, to the position below the lower lip tip 5b, A plurality of axially extending grooves 10, 10 ... Are formed side by side in the circumferential direction.

Since other parts are the same as those in the above-mentioned embodiment,
The same parts are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment as well, the contact area between the lip portion 4 and the shaft 9 can be reduced by the groove 10 even when the sealing fluid has a high pressure, as in the case of the above embodiment. The resistance during movement can be significantly reduced, and as a result, the friction of the lip portion 4 can be reduced, deterioration of the lip portion 4 due to heat generation can be prevented, and the life of the lip portion 4 can be extended.

It should be noted that the present invention is not limited to the above-described embodiments, but various modifications can be made as necessary.

[Effect of device]

As described above, in the reciprocating sealing device according to the present invention, the groove can significantly reduce the contact area between the lip portion and the member that relatively moves in the axial direction when the sealing fluid has a high pressure. It is possible to reduce the resistance during the reciprocating movement of, and to smoothly reciprocate the member. Moreover, it is possible to reduce the friction of the lip portion,
It is possible to prevent the deterioration of the lip portion due to heat generation and to achieve a longer life.

[Brief description of drawings]

1 is a longitudinal sectional view showing an embodiment of the reciprocating sealing device of the present invention, FIG. 2 is a lateral sectional view of the lip portion at high pressure of the sealing fluid of FIG. 1, and FIG. FIG. 4 is a vertical sectional view showing another embodiment, and FIG. 4 is a vertical sectional view showing a conventional reciprocating sealing device. 1 ... Reinforcement ring, 2 ... Seal lip, 4 ... Lip part,
5,5a, 5b …… Lip tip, 6 …… Spring, 8 ……
Housing, 9 ... Shaft, 10 ... Groove.

Claims (1)

[Scope of utility model registration request] 1. A seal lip is integrally fixed to an annular metallic reinforcing ring, and a lip portion is formed on the inner peripheral surface of the seal lip, the inner peripheral surface being in contact with the outer peripheral surface of the reciprocating member. In the reciprocating sealing device as described above, a plurality of grooves extending in the axial direction are formed in a portion of the inner peripheral surface of the lip portion that is separated from the lip tip portion by a predetermined length in the axial direction. Dynamic sealing device.