JPH061935U - Oil seal - Google Patents

Abstract

(57) [Summary] [Purpose] To extend the durability of the sealing function. In the oil seal 1 for sealing between the two members 2 and 3 arranged so as to be relatively movable, instead of the primary seal 4 for performing initial sealing and the primary seal 4 after the sealing function of the primary seal 4 is lowered. The secondary seal 5 for sealing is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an oil seal that seals between two members arranged so as to be relatively movable.

[0002]

[Prior art]

 Conventionally, an oil seal has a seal portion that seals between two members arranged so as to be relatively movable.

[0003]

[Problems to be solved by the device]

 However, in the above-mentioned conventional oil seal, only the above-mentioned seal portion is sealed, and when the sealing function of the seal portion deteriorates, the entire oil seal was replaced.

That is, maintenance of the sealing function (improvement of durability) was attempted by replacing the entire oil seal.

By the way, when the oil seal is replaced, the price of the oil seal itself is low, which is good, but the cost of the work for replacing the oil seal is high, and in the end, the entire oil seal is replaced. And it costs a lot of money.

The present invention has been made to solve the above problems, and its purpose is to increase the durability of the sealing function longer than that of the conventional oil seal, thereby changing the frequency of replacement of the entire oil seal. It is to provide an oil seal that can lower the oil consumption.

[0007]

[Means for Solving the Problems]

 To achieve the above object, in the present invention, in an oil seal that seals between two parts that are arranged so that they can move relative to each other, a primary seal that performs an initial seal, and a seal function after the primary seal is deteriorated And a secondary seal that seals in place of the primary seal.

[0008]

[Action]

 In the oil seal according to the present invention having the above structure, the initial seal is performed by the primary seal. Then, after the sealing function of the primary seal is deteriorated due to wear or the like, the secondary seal replaces the primary seal and then seals. This makes it possible to prolong the durability of the sealing function and reduce the frequency of replacement of the entire oil seal, compared to conventional oil seals that only have a seal that performs the initial sealing.

[0009]

【Example】

 The present invention will be described below based on the illustrated embodiment.

1 to 3, reference numeral 1 denotes an oil seal according to an embodiment of the present invention, which is a housing 2 as one member of two members movably arranged relative to each other, and an other member. The shaft 3 and the shaft 3 are sealed.

The oil seal 1 is roughly composed of a primary seal 4 that performs an initial sealing and a secondary seal 5 that performs sealing in place of the primary seal 4 after the sealing function of the primary seal 4 deteriorates. ing.

The secondary seal 5 is roughly made up of a metal-made secondary seal can 6 that is fitted into the housing 2 while being press-fitted, and a rubber or the like fixed to the end of the secondary seal can 6 on the shaft side. From the secondary seal main lip 7 made of an elastic member, and the secondary seal spring 8 which is fitted into the housing side of the secondary seal main lip 7 and biases the secondary seal main lip 7 toward the shaft side. It is configured.

The secondary seal can 6 includes a pressure contact portion 9 that is in pressure contact with the housing 2, and a reduced diameter portion 10 that is bent stepwise from one end of the pressure contact portion 9 on the atmosphere side A 1 and has a diameter smaller than that of the pressure contact portion 9. A secondary seal ring portion 11 bent from one end on the atmosphere side A of the reduced diameter portion 10 to the shaft side, and a secondary seal ring portion bent from one end on the shaft side of the secondary seal ring portion 11 toward the oil side B. And an end 12 to which the lip 7 is fixed.

The secondary seal main lip 7 is separated from the shaft 3 at an initial stage, but the secondary seal main lip end 13 is in sliding contact with the shaft 3 after the sealing function of the primary seal 4 is deteriorated, and a primary seal described later. And a secondary seal contact portion 14 that contacts the primary seal main lip in a pressed state.

The primary seal 4 is disposed on the atmosphere side A with respect to the secondary seal 5, and is fitted to the outer periphery of the reduced diameter portion 10 of the secondary seal can 6, and the metal primary seal can 15 and the primary seal A primary seal body 16 made of an elastic material such as rubber, which is fixed to the can 15 and fits into the housing 2 and seals with the shaft 3.

The primary seal can 15 includes a tubular portion 17 fitted on the outer circumference of the reduced diameter portion 10 of the secondary seal can 6, and a tip end that is bent from one end of the tubular portion 17 on the atmosphere side A toward the shaft side. The secondary seal ring portion 11 and the bent portion 18 facing each other are provided.

The primary seal body 16 is located on the outer periphery of the primary seal can 15 and is fitted with the housing 2. The fitting portion 19 is located on the atmosphere side A of the bending portion 18, and the atmosphere side A is located on the atmosphere side A. A primary seal dust strip 21 for preventing dust and the like from entering, a primary seal main lip 22 for initial sealing by sliding contact with the shaft 3, and a primary seal beard lip 23 for contacting the secondary seal ring portion 11. , With.

Here, the bent portion 18 of the primary seal can 15 and the atmosphere side portion 20 of the primary seal body 16 constitute a primary seal ring portion 24, and the primary seal ring portion 24 includes the secondary seal ring portion 11. Is provided with a screw hole 25 for moving the primary seal.

The fitting portion 19 of the primary seal body 16 is composed of a plurality of axially extending projections 26 provided on the outer periphery of the primary seal body 16 at regular intervals.

Then, the primary seal main lip 22 comes into contact with the primary seal main lip end 27 that is in sliding contact with the shaft 3 and the above-mentioned secondary seal abutment portion 14 while being urged toward the shaft side. And a primary seal contact portion 28.

In the present embodiment having the above-described structure, in the initial state in which the oil seal is mounted between the two members 2 and 3, the primary seal main lip 22 is in sliding contact with the shaft 3 and the secondary seal The main lip 7 is separated from the shaft 3.

This is because the secondary seal main lip 7 is urged toward the shaft side by the secondary seal spring 8, but the secondary seal contact portion 14 contacts the primary seal contact portion 28. At the initial stage, the secondary seal main lip 7 is held so as to be separated from the shaft 3.

Then, the urging force of the secondary seal spring 8 is transmitted to the primary seal main lip 22 via the secondary seal contact portion 14 and the primary seal contact portion 28, and the primary seal main lip 22 performs the initial sealing. To do.

At this time, the primary seal beard lip 23 is brought into contact with the secondary seal ring portion 11 so that the primary seal ring lip 24 is exposed to the atmosphere side through the screw hole 25 for moving the primary seal ring formed in the primary seal ring portion 24. It is provided to prevent the A and the oil side B from communicating with each other so that the seal is not made.

After a while, when the sealing function of the primary seal main lip 22 deteriorates due to wear or the like, the secondary seal 5 is used instead of the primary seal 4.

That is, the screw 29 as shown in FIG. 3 is screwed into the screw hole 25 for primary sealing. Then, the end surface of the screw 29 comes into contact with the secondary seal wheel portion 11, and if it is further screwed, the primary seal 4 moves to the atmosphere side A with respect to the secondary seal 5 by a predetermined distance d.

Since the secondary seal can 6 is made of metal, the pressing force on the housing 2 is stronger than the fitting portion 19 of the primary seal 4 made of an elastic member, and the mounting strength is higher, so that the screw 29 The primary seal 4 is moved to the atmosphere side A by screwing.

In particular, in this embodiment, since the fitting portion 19 of the primary seal 4 is composed of the plurality of protrusions 26 extending in the axial direction, the movement toward the atmosphere side A in the axial direction is smoothly performed. Be done.

When the primary seal 4 moves to the atmosphere side A as shown in FIG. 3, the support of the primary seal contact portion 28 also moves to the atmosphere side A, and the support is lost. The secondary seal main lip 7 is brought into sliding contact with the shaft 3 by the urging force of the secondary seal spring 8. Then, the secondary seal main lip 7 then seals in place of the primary seal main lip 22.

At this time, the primary seal main lip 22 replaces the central role of sealing up to that point and the role of assisting the sealing of the secondary seal main lip 7.

Since the secondary seal main lip 7 seals for the first time at this time, it has a function similar to that of a new product.

As a result, the durability of the sealing function can be extended and the frequency of replacement of the entire oil seal can be kept low compared to conventional oil seals that only have a seal portion for performing initial sealing. The cost of replacing the oil seal can be reduced.

In this embodiment, the primary seal 4 is arranged on the atmosphere side A and the secondary seal 5 is arranged on the oil side B, but the invention is not limited to this, and the reverse arrangement is also possible. .

Further, after the sealing function of the primary seal 4 has deteriorated, the primary seal 4 is not moved to the atmosphere side A, the primary seal main lip 22 is allowed to wear as it is, and the secondary seal main lip is naturally awaited. Waiting for 7 to come into contact with the shaft 3 by the urging force of the secondary seal spring 8, the sealing performance is poor and the condition is not good during the transition from the primary seal 4 to the secondary seal 5, but In this embodiment, the primary seal 4 having a deteriorated function is immediately moved by the screw 29 so as to be replaced by the secondary seal 5, so that the sealing function can be immediately improved.

[0035]

[Effect of device]

 As described above, in the oil seal according to the present invention, the initial sealing is performed by the primary seal. Then, after the sealing function of the primary seal deteriorates due to wear or the like, the secondary seal replaces the primary seal and then seals. This makes it possible to extend the durability of the sealing function and reduce the frequency of replacement of the entire oil seal, as compared with the conventional oil seal that has only the seal portion that performs the initial sealing.

[Brief description of drawings]

FIG. 1 is a semi-longitudinal sectional view of an oil seal according to an embodiment of the present invention.

FIG. 2 is a plan view seen from the atmosphere side A in FIG.

FIG. 3 is a view for explaining the action of the oil seal.

[Explanation of symbols]

 1 Oil seal 2 Housing (one member of the two members) 3 Shaft (other member of the two members) 4 Primary seal 5 Secondary seal

Claims (1)

[Scope of utility model registration request] 1. An oil seal for sealing between two members arranged so as to be movable relative to each other, wherein a primary seal which performs an initial sealing and a sealing which replaces the primary seal after the sealing function of the primary seal deteriorates. An oil seal having a secondary seal.