JPH066831U - Sealing device - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a highly durable sealing device that prevents dust and water from entering through the spiral groove provided in the dust lip when the shaft is stopped. [Structure] Helical groove 1 provided in dust lip 16
7 is characterized in that it does not penetrate the space 18 between the first and second sealing members 2 and 12 from the atmosphere side. In addition, in the engaging portion for assembling the first and second seal members 2 and 12,
The breather portion 19 for releasing the pressure in the space between the first and second seal members 2 and 12 is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device applied to various shaft sealing parts, and more particularly, to an assembly type sealing device.

[0002]

[Prior art]

 As a conventional sealing device of this type, for example, there is one shown in FIG. That is, the sealing device 100 seals the gap between the housing 107 and the rotary shaft 108 inserted into the housing 107, and is arranged on the oil side O to seal the fluid to be sealed such as oil. It comprises a first seal member 101 and a second seal member 102 arranged on the atmosphere side A of the first seal member 101.

The second seal member 102 includes a dust lip 105 slidably sealingly contacting the rotary shaft 108, and a spiral groove 106 is provided on a sliding surface on the inner periphery of the dust lip 105. It was

When the rotary shaft 108 rotates, it enters between the sliding surfaces of the dust lip 105 and the rotary shaft 108 due to the labyrinth effect of the spiral groove 106 formed in the dust lip 105 and a kind of screw pump effect. The dust and water that came in were pushed back to effectively prevent the intrusion of dust from the outside into the interior.

[0005]

[Problems to be solved by the device]

 However, in the case of the above-mentioned conventional technique, when the rotating shaft 108 stops, the labyrinth effect and the pump effect as described above do not occur, and dust, water, etc. pass through the spiral groove 106 and the first, second There is a problem in that it enters the space between the seal members 101 and 102, adversely affects the main lip 103 and the auxiliary lip 104 of the first seal member 101, and shortens the life.

The present invention was made in order to solve the above-mentioned problems of the prior art. The purpose of the present invention is to prevent dust, water, etc. from entering through the spiral groove provided in the dust lip when the shaft is stopped. To provide a highly durable sealing device.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, in the present invention, a gap between a housing and a shaft concentrically and rotatably assembled with the housing is sealed, and a fluid to be sealed such as oil is sealed. And a ring-shaped second seal member disposed on the atmosphere side of the first seal member, the second seal member being provided with respect to the shaft outer peripheral surface. In a sealing device having a dust lip that slidably and slidably contacts with a spiral groove formed on the inner peripheral surface of the dust lip, the spiral groove provided in the dust lip is the first seal member from the atmosphere side. It is characterized in that it does not penetrate into the space between the second seal member and the second seal member.

Further, the first seal member and the second seal member are integrally assembled via an engaging portion which engages with each other, and the engaging portion has the first seal member and the second seal member. It is characterized by the provision of a breather section for releasing the pressure in the space between the outside.

[0009]

[Action]

 In the present invention, when the housing and the shaft rotate relative to each other, the labyrinth effect of the spiral groove provided on the sliding surface of the dust lip and the screw pump effect effectively prevent the intrusion of dust and water.

On the other hand, since the spiral groove does not penetrate to the first seal member side, invasion of dust, water, etc. to the first seal member side is prevented when the shaft is stopped.

Further, when the space between the first seal member and the second seal member becomes high in pressure due to sliding heat generation or the like, the pressure is released through the breather portion and the pressure in the space is adjusted.

[0012]

【Example】

 The present invention will be described below based on the illustrated embodiment. FIG. 1 shows a sealing device according to an embodiment of the present invention. The sealing device has a first seal member 2 for sealing an object to be sealed such as roughly oil, and a dust lip 16 is provided for the purpose of improving the sealability of the first seal member 2 against dust and water. The 2nd sealing member 12 which it has is attached.

The first seal member 2 is an outer peripheral rubber type oil seal in which a rubber-like elastic body is baked on the first metal ring 1, and is attached to the outer peripheral fitting portion 7 of the first metal ring 1 fitted in the housing 30. The rubber-like elastic body is baked. On the other hand, a main lip 4 for sealing oil and the like and an auxiliary lip 6 for sealing dust and holding grease are provided on the inner diameter end side of the first metal ring 1. The main lip 4 extends toward the oil side, and a spring member 3 such as a garter spring for applying a tightening force is attached to the outer periphery of the main lip 4. Further, the auxiliary lip 6 extends from the base end portion of the main lip 4 to the side opposite to the main lip 4, and the space between the main lip 4 and the auxiliary lip 6 is a grease filling space 5.

The second seal member 12 also has a structure in which a rubber-like elastic body is baked on the second metal ring 11, and a dust lip 16 is provided at the inner diameter end of the second metal ring 11. The dust lip 16 has a bellows-shaped waist portion 15, and the tip of the lip extends toward the oil side O in the axial direction. The sliding surface of the dust lip 16 with respect to the shaft 31 is provided with a single-line or multi-line spiral groove 17 in the direction opposite to the axial rotation direction.

The second seal member 12 is attached to the first metal ring 1 of the first seal member 2. That is, the atmosphere side edge of the first metal ring 1 of the first seal member 2 is extended in the axial direction to form the first assembly guide member 8, and the inner periphery of the first assembly guide portion 8 is The second assembly guide portion 13 provided on the second metal ring 11 of the two-seal member 12 is fitted. The second assembling guide portion 13 extends in a cylindrical shape from the outer diameter end of the second metal ring 11 toward the atmosphere side in the axial direction. A positioning flange 14 is provided which projects outward in the radial direction.

Further, the first assembly guide portion 8 of the first metal ring 1 has an atmosphere-side end edge that extends radially outward, and the outer edge is further bent toward the atmosphere to form a cylindrical shape. A bent first flange portion 9 is provided, and a positioning flange 14 is abutted against the first flange portion 9 to position the first and second sealing members 2 and 12 together. At this position, the dust lip 16 of the second seal member 12 is close to the auxiliary lip 6 of the first seal member 2, and the space between the dust lip 16 and the auxiliary lip 6 is the grease filling space. It is 18.

Then, the atmosphere side end edge of the first flange portion 9 is caulked inward, and the caulking portion 10 presses the positioning flange 14 of the second seal member 12, and the first and second seal portion members 2, 12 are integrated. These first and second assembly guide portions 8 and 13, the positioning flange 14 and the first flange portion 9 are engaging portions for integrally assembling the first and second seal members 2 and 12. Are configured.

On the other hand, the inner surface of the dust lip 16 in which the spiral groove 17 is provided has a taper shape in which the diameter gradually decreases from the atmosphere side toward the oil side, and the spiral groove 17 has the first seal member 2 and the second seal member 2. The lip tip 16a is provided with a grooveless region B so as not to penetrate into the grease filling space 18 between the seal members 12, and the grooveless region B is configured to be in close contact with the shaft 31 over the entire circumference. ing.

As described above, since the spiral groove 17 does not penetrate from the atmosphere side to the grease filling space 18, dust and water are prevented from entering the first seal member 2 side when the shaft 31 is stopped.

On the other hand, at the time of shaft rotation, in the groove area A having the spiral groove 17, a labyrinth effect and a screw pump effect are generated by the gap between the shaft 31 and the dust lip 16, pushing back dust or the like to maintain good sealing performance. To be done.

Further, since the spiral groove 17 does not penetrate from the atmosphere side to the grease filling space 18, the pressure in the grease filling space 18 becomes high due to sliding heat generation of the dust lip 16 and the auxiliary lip 6 and the like. In this case, the dust lip 16 and the auxiliary lip 6 may be deformed by the pressure, which may cause a bad effect such as a defective seal.

Therefore, a breather portion 19 for releasing the pressure of the grease-filled space 18 to the atmosphere is provided. In this invention, the breather portion 19 is provided on the first and second flange portions 9 and 14 which are engaged with each other to assemble the first and second sealing members 2 and 12.

The breather portion 19 has one or many lips 20. In this embodiment, the lip 20 is provided on the outer diameter end of the positioning flange 14 of the second seal member 12 so as to extend radially outward, as shown in FIG. Is in sealing contact with the inner peripheral surface of the first flange portion 9.

Further, at the contact portion between the first flange portion 9 and the positioning flange 14, one or a plurality of protrusions 21 and grooves 22 for allowing air to escape from the grease filling space 18 to the atmosphere side A are provided. If the pressure in the filling space 18 rises too much, the lip 20 opens and reduces the pressure in the grease filling space 18.

Further, the lip 20 is normally closed to prevent dust, water and the like from entering from the breather portion 19.

[0026]

[Effect of device]

 The present invention has the above-described configuration and operation. Since the spiral groove that does not penetrate into the space between the first and second seal members is provided on the inner peripheral surface of the dust lip of the second seal member, During rotation, dust and water can be pushed back by the labyrinth effect due to the gap between the shaft and dust lip and by the effect of a screw pump, and dust and water can be prevented from entering when the shaft is stopped.

Further, since the pressure in the space between the first and second seal members can be adjusted by providing the breather portion in the engaging portion between the first and second seal members, sliding heat generation of the lip can be achieved. The space will not become high pressure and will not adversely affect the dust lip.

[Brief description of drawings]

1A and 1B show a sealing device according to an embodiment of the present invention, in which FIG. 1A is a longitudinal sectional view of a main portion, and FIG. 1B is an enlarged sectional view of a dust lip portion. (C) is an enlarged sectional view of the breather portion.

FIG. 2 (a) is a longitudinal sectional view of a main part of a conventional sealing device,
FIG. 2B is an enlarged cross-sectional view of the dust lip portion shown in FIG.

[Explanation of symbols]

 1 1st metal ring 2 1st sealing member 3 Spring member 4 Main lip 5 Grease filling space 6 Auxiliary lip 7 Outer periphery fitting part 8 1st assembly guide part 9 1st flange part 10 Crimping part 11 2nd metal ring 12th 2 seal member 13 second assembly guide portion 14 positioning flange 15 waist portion 16 dust lip 17 spiral groove 18 grease filling space 19 breather portion 20 lip 21 protrusion 22 groove

Claims (2)

[Scope of utility model registration request] 1. A ring-shaped first for sealing a gap between a housing and a shaft concentrically and relatively rotatably assembled with the housing, and for sealing a fluid to be sealed such as oil.
A seal member and an annular second seal member arranged on the atmosphere side of the first seal member, wherein the second seal member slidably and sealingly contacts the shaft outer peripheral surface. In a sealing device having a strip and forming a spiral groove on an inner peripheral surface of the dust lip, a spiral groove provided on the dust lip is provided in a space between the first seal member and the second seal member from an atmosphere side. A sealing device having a structure that does not penetrate. 2. The first seal member and the second seal member are integrally assembled via an engaging portion that engages with each other, and the engaging portion has a space between the first seal member and the second seal member. The sealing device according to claim 1, further comprising a breather portion for releasing the pressure in the space of the outside to the outside.