WO2010143694A1

WO2010143694A1 - Sealing device

Info

Publication number: WO2010143694A1
Application number: PCT/JP2010/059869
Authority: WO
Inventors: 佐藤彰洋
Original assignee: Nok株式会社
Priority date: 2009-06-10
Filing date: 2010-06-10
Publication date: 2010-12-16
Also published as: JP2010286023A

Abstract

Provided is a sealing device wherein improvement of sealing performance is realized. Disclosed is a sealing device (100) which seals the annular gap between a shaft hole provided in a housing (300) and a rotary shaft (200) inserted through the aforementioned shaft hole, and which is provided with an annular section (111) comprising a tubular section (111a) fixed to the rotary shaft (200); a slinger (110) equipped with an outward flange section (112) extending from the end of the annular section (111) in the direction of the outside diameter; and a seal member (120) equipped with a seal lip (122b) that is fixed to the shaft hole portion of the housing (300), that extends in the direction of the outside diameter, and that is capable of freely sliding with respect to the outward flange section (112). The sealing device (100) is characterized by an arrangement wherein, on that surface of the outward flange section (112) where the seal lip (122b) slides, threaded protrusions are provided which generate fluid flows toward an outside diameter area in keeping with the rotation of the rotary shaft (200), the aforementioned threaded protrusions being located in an inside diameter area beyond the region where the seal lip (122b) slides and in an outside diameter area beyond the aforementioned region.

Description

Sealing device

The present invention relates to a sealing device provided with a slinger.

Conventionally, a sealing device provided with a slinger is known. A sealing device according to such a conventional example will be described with reference to FIGS. FIG. 4 is a schematic cross-sectional view of a conventional sealing device. FIG. 5 is a partially broken perspective view of a slinger in a sealing device according to a conventional example.

The sealing device 500 seals an annular gap between a shaft hole provided in the housing and a rotating shaft inserted through the shaft hole. In FIG. 4, the lower side is a side (hereinafter referred to as oil side O) on which oil scatters or flows in, and the upper side is the atmosphere side A. The sealing device 500 includes a slinger 510 fixed to the rotating shaft and a seal member 520 fixed to the shaft hole side of the housing.

The slinger 510 includes an annular part 511 having a cylindrical part 511a fixed to the rotating shaft, and an outward flange part 512 extending from the end of the annular part 511 in the outer diameter direction.

Also, the seal member 520 includes a reinforcing ring 521 and a seal body 522 made of a rubber-like elastic body that is integrally formed with the reinforcing ring 521. The seal body 522 includes an outer peripheral seal portion 522a that is in close contact with the inner peripheral surface of the shaft hole of the housing, and a seal lip 522b that is slidable with respect to the outward flange portion 512 of the slinger 510. The seal member 520 also includes a felt dust 523 slidable on the cylindrical portion 511 a of the slinger 510.

In the outward flange portion 512 of the slinger 510, a thread groove 512a is provided in a region where the seal lip 522b of the seal member 520 slides. The thread groove 512a is configured to generate a fluid flow toward the outer diameter side when the slinger 510 rotates together with the rotating shaft.

It is possible to suppress the oil on the oil side O from leaking to the atmosphere side A by the sealing device 500 according to the conventional example configured as described above. Further, even if the oil tries to escape to the atmosphere side A from the sliding portion between the outward flange portion 512 and the seal lip 522b of the slinger 510, it will try to escape due to the fluid flow generated by the thread groove 512a when the rotary shaft rotates. The oil to be returned can be returned to the oil side O.

In the normal state, the sealing device 500 according to this conventional example is used so that oil exists on the lower side (oil side O) in FIG. 4 with respect to the outward flange portion 512 of the slinger 510. 522b is not always exposed to oil. However, depending on the use situation (for example, the situation where the machine in which the sealing device 500 is used is tilted), the oil may be accumulated for a long time on the upper side in FIG. Even in this case, when the rotating shaft rotates, there is no problem because the fluid flow is generated toward the outer diameter side by the thread groove 512a as described above.

However, this fluid flow does not occur when the rotating shaft is stationary. Therefore, in an environment where the seal lip 522b is exposed to oil for a long time while the rotating shaft remains stationary, the oil may leak depending on the amount of oil and the viscosity of the oil. That is, in the sealing device 500 according to the conventional example, the threaded groove 512a is provided in the region where the seal lip 522b slides in the outward flange portion 512 of the slinger 510. For this reason, the thread groove 512a forms a gap that connects the inner diameter side and the outer diameter side with respect to the sliding region of the seal lip 522b. As a result, when the rotating shaft is stationary, the oil may leak to the inner diameter side of the seal lip 522b.

Japanese Patent Laid-Open No. 2-113173

An object of the present invention is to provide a sealing device with improved sealing performance.

The present invention employs the following means in order to solve the above problems.

That is, the sealing device of the present invention is
A sealing device that seals an annular gap between a shaft hole provided in a housing and a rotating shaft inserted through the shaft hole,
A slinger comprising an annular portion having a cylindrical portion fixed to the rotating shaft, and an outward flange portion extending in an outer radial direction from an end portion of the annular portion;
A seal member which is fixed to the shaft hole side of the housing and includes a seal lip which extends in an outer radial direction and is slidable with respect to an outward flange portion of the slinger;
A sealing device comprising:
The surface of the outward flange portion on which the seal lip slides is closer to the inner diameter side and the outer diameter side than the sliding area of the seal lip toward the outer diameter side as the rotary shaft rotates. Screw projections for generating a fluid flow are provided, respectively.

Another sealing device of the present invention is:
A sealing device that seals an annular gap between a shaft hole provided in a housing and a rotating shaft inserted through the shaft hole,
A slinger comprising an annular portion having a cylindrical portion fixed to the rotating shaft, and an outward flange portion extending in an outer radial direction from an end portion of the annular portion;
A seal member which is fixed to the shaft hole side of the housing and includes a seal lip extending in an outer radial direction and slidable with respect to an outward flange portion of the slinger;
A sealing device comprising:
On the surface side where the seal lip slides in the outward flange portion, toward the inner diameter side and the outer diameter side from the sliding area of the seal lip, toward the outer diameter side as the rotary shaft rotates. A screw groove for generating a fluid flow is provided, respectively.

According to these inventions, when the rotary shaft rotates, a fluid flow is generated toward the outer diameter side by the screw projections and screw grooves provided on the outward flange portion of the slinger near the sliding portion of the seal lip. To do. Thereby, the leakage of the fluid can be effectively suppressed. In addition, since the screw protrusions and screw grooves are provided on the inner diameter side and the outer diameter side of the seal lip sliding area, these screw protrusions and screw grooves are sealed in the sealing lip sliding area. Will not be adversely affected. That is, when the rotating shaft is stationary, these screw protrusions and screw grooves do not cause fluid leakage.

As described above, according to the present invention, the sealing performance can be improved.

1 is a schematic cross-sectional view of a sealing device according to Embodiment 1 of the present invention. FIG. 2 is a partially broken perspective view of the slinger in the sealing device according to the first embodiment of the present invention. FIG. 3 is a partially broken perspective view of the slinger in the sealing device according to the second embodiment of the present invention. FIG. 4 is a schematic cross-sectional view of a conventional sealing device. FIG. 5 is a partially broken perspective view of a slinger in a sealing device according to a conventional example.

DETAILED DESCRIPTION Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

Example 1
<Configuration of sealing device>
With reference to FIG.1 and FIG.2, the sealing device which concerns on Example 1 of this invention is demonstrated. The sealing device 100 according to the present embodiment seals an annular gap between a shaft hole provided in the housing 300 and the rotary shaft 200 inserted through the shaft hole. In FIG. 1, the lower side is a side on which oil scatters or oil flows (hereinafter referred to as oil side O), and the upper side is an atmospheric side A. In FIG. 1, only the outer peripheral surface of the rotating shaft 200 is indicated by a dotted line, and only the inner peripheral surface of the shaft hole is indicated by a dotted line with respect to the housing 300.

The sealing device 100 according to the present embodiment includes a slinger 110 fixed to the rotary shaft 200 and a seal member 120 fixed to the shaft hole side of the housing 300.

The slinger 110 includes an annular portion 111 having a cylindrical portion 111a fixed to the rotating shaft 200, and an outward flange portion 112 extending from the end on the oil side O of the annular portion 111 in the outer diameter direction. .

Further, the seal member 120 includes a reinforcing ring 121 and a seal body 122 made of a rubber-like elastic body formed integrally with the reinforcing ring 121. The reinforcing ring 121 includes an annular portion 121a having a cylindrical portion 121a1 that is fitted to the inner periphery of the shaft hole of the housing 300, and an inward support portion 121b that extends from the end on the atmosphere side A toward the inner diameter side of the annular portion 121a. And.

The seal body 122 includes an outer peripheral seal portion 122a that is in close contact with the inner peripheral surface of the shaft hole of the housing 300, and a seal lip 122b that is slidable with respect to the outward flange portion 112 of the slinger 110. The seal lip 122b extends from the vicinity of the tip of the inward support portion 121b that supports most of the seal body 122 toward the outer diameter direction and the oil side O, and the vicinity of the tip contacts the outward flange portion 112. It is configured as follows. A region indicated by X in FIG. 2 is a region where the seal lip 122 b slides in the outward flange portion 112.

The seal member 120 also includes a felt dust lip 123 slidable on the cylindrical portion 111 a of the slinger 110.

In the outward flange portion 112 of the slinger 110, on the surface side where the seal lip 122b slides, a plurality of

screw projections

112a and 112b are provided on the inner diameter side and the outer diameter side from the sliding region X of the seal lip 122b. Is provided. These screw

protrusions

112a and 112b exhibit a function of generating a fluid flow toward the outer diameter side by rotating the slinger 110 as the rotating shaft 200 rotates. That is, in the present embodiment, the slinger 110 is configured to rotate together with the rotating shaft 200 in the direction of arrow R in FIG. Therefore, the

screw protrusions

112a and 112b are configured to be inclined from the inner diameter side toward the outer diameter side toward the opposite side to the rotation direction. Thereby, when the slinger 110 rotates together with the rotating shaft 200, a fluid flow is generated from the inner diameter side toward the outer diameter side along the

screw protrusions

112a and 112b. When the rotation direction of the rotating shaft 200 is opposite, the direction in which the

screw protrusions

112a and 112b are inclined may be set to the opposite side. The positions where the

screw projections

112a and 112b are arranged, the number of the

screw projections

112a and 112b, and the height of the projections may be appropriately set according to the rotational speed of the rotating shaft 200, the viscosity of the oil, and the like.

Note that air flows from the sliding portion between the outward flange portion 112 of the slinger 110 and the seal lip 122b to the oil side (O) by the flow of fluid generated by these

screw projections

112a and 112b. However, since the dust lip 123 is made of a felt material and has air permeability, the space region surrounded by the slinger 110, the seal lip 122b, and the dust lip 123 does not become negative pressure.

<Excellent point of sealing device according to this embodiment>
According to the sealing device 100 according to the present embodiment, when the rotary shaft 200 rotates, the outer diameter of the seal lip 122b near the sliding portion is increased by the

screw protrusions

112a and 112b provided on the outward flange portion 112 of the slinger 110. Fluid (air or oil) flows toward the side. Thereby, the leakage to the atmosphere side A of oil can be suppressed effectively.

Further, the

screw protrusions

112a and 112b are provided on the inner diameter side and the outer diameter side from the sliding region X of the seal lip 122b, respectively. Therefore, the

screw protrusions

112a and 112b do not adversely affect the sealing performance in the sliding region X of the seal lip 122b. That is, when the rotary shaft 200 is stationary, the

screw protrusions

112a and 112b do not cause oil leakage.

In the present embodiment, the sliding region X of the seal lip 122b in the outward flange portion 112 is configured by a plane, and the sliding portion of the seal lip 122b has an inner diameter side and an outer diameter side of the sliding region X. There is no gap that communicates. Therefore, even when the seal lip 122b is exposed to oil for a long time and the rotating shaft 200 is stationary and no fluid flow is generated by the

screw protrusions

112a and 112b, the oil remains on the atmosphere side. It is possible to prevent leakage to A.

(Example 2)
FIG. 3 shows a second embodiment of the present invention. In the first embodiment, the case of the screw protrusion is shown as the one that generates the flow of the fluid toward the outer diameter side. However, in this embodiment, the case of the screw groove is used as the one that generates the flow of the fluid. Show. Since other configurations and operations are the same as those of the first embodiment, the description of the same components is omitted.

The sealing device according to the present embodiment is also composed of the slinger 150 and the seal member 120 as in the case of the first embodiment. Since the seal member 120 has the same configuration as that of the first embodiment, the description thereof is omitted.

Further, the slinger 150 according to the present embodiment also includes an annular portion 151 and an outward flange portion 152 as in the case of the first embodiment. In the present embodiment, in the outward flange portion 152 of the slinger 150, the surface side on which the seal lip 122b slides is more than the sliding region X of the seal lip 122b.

Screw grooves

152a and 152b are provided. These

thread grooves

152a and 152b exhibit the function of generating a fluid flow toward the outer diameter side by rotating the slinger 150 as the rotating shaft 200 rotates. That is, in this embodiment, the slinger 150 is configured to rotate together with the rotary shaft 200 in the direction of arrow R in FIG. Therefore, the

screw grooves

152a and 152b are configured to be inclined from the inner diameter side toward the outer diameter side toward the opposite side to the rotation direction. Thereby, when the slinger 150 rotates with the rotating shaft 200, a fluid flow is generated from the inner diameter side toward the outer diameter side along the

thread grooves

152a and 152b. When the rotation direction of the rotating shaft 200 is opposite, the direction in which the

screw grooves

152a and 152b are inclined may be opposite. In addition, the position where the

screw grooves

152a and 152b are arranged, the number of the arranged grooves, and the groove depth may be appropriately set according to the rotational speed of the rotating shaft 200, the viscosity of the oil, and the like.

Needless to say, even in the case of the sealing device according to the present embodiment configured as described above, the same effects as those of the first embodiment are exhibited.

DESCRIPTION OF SYMBOLS 100 Sealing device 110 Slinger 111 Annular part 111a Cylinder part 112

Flange part

112a, 112b Screw protrusion 120 Seal member 121 Reinforcement ring 121a Annular part 121a1 Cylindrical part 121b Support part 122 Seal body 122a Outer peripheral seal part 122b Seal lip 123 Dustrip 150 Slinger 151 Annular part 152

Flange part

152a, 152b Thread groove 200 Rotating shaft 300 Housing

Claims

A sealing device that seals an annular gap between a shaft hole provided in a housing and a rotating shaft inserted through the shaft hole,
A slinger comprising an annular portion having a cylindrical portion fixed to the rotating shaft, and an outward flange portion extending in an outer radial direction from an end portion of the annular portion;
A seal member which is fixed to the shaft hole side of the housing and includes a seal lip which extends in an outer radial direction and is slidable with respect to an outward flange portion of the slinger;
A sealing device comprising:
The surface of the outward flange portion on which the seal lip slides is closer to the inner diameter side and the outer diameter side than the sliding area of the seal lip toward the outer diameter side as the rotary shaft rotates. A screw device for generating a fluid flow is provided, respectively.
A sealing device that seals an annular gap between a shaft hole provided in a housing and a rotating shaft inserted through the shaft hole,
A slinger comprising an annular portion having a cylindrical portion fixed to the rotating shaft, and an outward flange portion extending in an outer radial direction from an end portion of the annular portion;
A seal member which is fixed to the shaft hole side of the housing and includes a seal lip which extends in an outer radial direction and is slidable with respect to an outward flange portion of the slinger;
A sealing device comprising:
The surface of the outward flange portion on which the seal lip slides is closer to the inner diameter side and the outer diameter side than the sliding area of the seal lip toward the outer diameter side as the rotary shaft rotates. A sealing device, wherein a thread groove for generating a fluid flow is provided.