JPH07293707A - Rotary shaft seal device - Google Patents

Abstract

PURPOSE:To reduce the oil leakage due to the positional between housings on the rotation side and the fixed side, and reduce the positional in the axial direction such as the axial deviation due to the external load by forming a sealing surface of an end surface part of an outer ring of a bearing and a fixed side seal ring. CONSTITUTION:In a rotary shaft seal device to seal a rotation side housing 17 and a fixed side housing 18 which are externally driven, a bearing 4 consists of an outer ring 1 1 of a bearing, a bearing roller 12, and an inner ring 13 of the bearing, and the inner ring 13 of the bearing is provided with an O-ring groove 13a to seal the fixed side housing 18 with an O-ring 16, and a joining part 15a to connect a fixed side seal ring 14 to a pressure load ring 15 of an elastic body. A sealing surface 14a is formed of a seal ring 11a integrated with the end surface of the outer ring 11 of thc bearing and the fixed side seal ring 14. This constitution reduces the axial deviation due to the external load and the self-weight to be applied to the housings 17, 18, and the positional variation in the axial direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary shaft sealing device, and more particularly to a rotary shaft sealing device for a shaft seal, which prevents intrusion of mud, water, etc. and leakage of enclosed oil to the outside.

[0002]

2. Description of the Related Art In a conventional rotary shaft sealing device, an axial end surface of an outer ring of a rotary shaft support bearing fitted in a fixed housing is used as a seal surface on the other side (for example, Japanese Patent Laid-Open No. 63-63). No. 135659), one of the sliding seal surfaces is formed into a flexible thin plate (see, for example, Japanese Utility Model Laid-Open No. 62-138959), mud, water, oil. There is an end face seal having a relatively short axial direction in order to prevent the intrusion of oil etc. and the leakage of the enclosed oil to the outside (see, for example, Japanese Patent Publication No. 61-21865).

[0003]

The above-mentioned conventional rotary shaft sealing device has the following problems. For example, in Japanese Patent Laid-Open No. 63-135659 shown in FIG.
The shaft 13 rotatably supports the housing 116 with respect to the shaft 114. Therefore, the shaft 114 bends due to the external force received by the housing 116 and its own weight, and the bearing 113
Due to the backlash and the deflection, the relative position of the axial end surface 113a of the bearing race with respect to the one housing 115 changes. The machining tolerances of the housing 115, the shaft 114, and the housing 116 and large parts are accumulated, and the axial position of the bearing race axial end 113a varies with respect to the housing 115. Since the O-ring 110 absorbs the fluctuation and variation of the relative position,
The amount of deformation of the ring 110 changes, and the seal 10 changes accordingly.
The pressing force for 4 fluctuates. If this variation exceeds the specified range, heat generation of the seal 104 may cause welding damage to the seal surface 112, and hardening of the O-ring 110 due to thermal deterioration may cause the oil sealed in the P portion to leak to the outside. Alternatively, oil leaks to the outside even if the pressing pressure of the sealing surface is insufficient.

FIG. 4 and FIG. 5 (Actual No. 62-13895)
No. 9) type, O-ring from outside 11
There is infiltration of earth and sand and water 2 on the 0, 223 surface. Also, due to the pressure due to freezing of earth and sand and water 2 etc. in cold regions,
The rings 110 and 223 move, causing seizure or oil leakage due to incorrect seal pressure due to slippage.

In the type shown in FIG. 5, the positional deviation in the axis 211 direction is large due to the misalignment of the rotating and stationary housings 212 and 213, and when the O-ring 223 exceeds the crushing margin, the amount of fluctuation of the seal 221 is increased. Oil leakage and seizure occur.

The present invention is directed to the rotating side, which has the above-mentioned conventional drawbacks.
Axial direction such as oil leak due to position change between fixed side housing, seal ring seizure, fraudulent prevention of seal pressure generated by pressure caused by freezing of sand and water in cold regions, misalignment due to external load, etc. It is an object of the present invention to provide a seal mechanism for a rotary shaft sealing device that reduces the positional fluctuation of the above, and further to provide a material constituting means of a seal surface using a composite material for improving wear resistance.

[0007]

In order to achieve the above object, according to a first aspect of the shaft sealing device of the present invention, a rotary side housing 17 and a fixed side housing 18 which are externally driven.
In the rotary shaft sealing device that seals and, the bearing 4 fitted in the rotary housing 17 has a bearing outer ring 11
, A bearing rolling element 12, and a bearing inner ring 13, and the bearing inner ring 13 has an O ring 16
There is an O-ring groove 13a for sealing with the fixed side housing 18 and a joint portion 15a for connecting the fixed side seal ring 14 to the elastic pressure load ring 15, and a seal integrally formed on the end surface of the bearing outer ring 11. The ring 11a and the fixed-side seal ring 14 constitute the sealing surface 14a.

A second aspect of the invention, which is mainly based on the first aspect, is that the bearing 4 fitted in the rotary housing 17 has a bearing outer ring 35 and a bearing inner ring having a sliding surface 36a between the bearing outer ring 35 and the bearing outer ring 35. It consists of 36 and
The bearing inner ring 36 has an O-ring groove 13a for sealing the fixed-side housing 18 with the O-ring 16, and a joint portion 15a for connecting the fixed-side seal ring 14 to the elastic pressure load ring 15. The seal ring 11a integrally formed on the end surface of the outer ring 35 and the fixed side seal ring 14
And constitute the sealing surface 14a.

In the third aspect of the invention, which is mainly composed of the first and second aspects, the stationary side housing 18 and the bearing inner ring 13 or 36 are joined by the meshing portion 30.

In the fourth invention, which is mainly composed of the first and second inventions, the pressure load ring 15 is baked and integrally connected to the joining partner by an elastic body such as rubber.

In the fifth aspect of the invention, the integrally formed seal ring 1 in the rotary shaft sealing device of the first aspect to the second aspect of the invention.
1a has a seal surface 14a with which the seal ring 14 contacts,
A material harder than the material of the bearing outer ring 11 or 35 is bonded.

[0012]

In the rotary shaft sealing device configured as described above, the bearing 4 holding the fixed side seal ring 14 is fitted in the rotary side housing 17, and the fixed side seal ring 14 is attached to the elastic pressure load ring 15. And the pressure loading ring 15
Since the O-ring groove 16a for sealing with the O-ring 16 provided on the stationary housing 18 and the joint portion 15a having the O-ring groove 13a integrally formed with the bearing inner ring 13 are also combined, the axial direction and the direction perpendicular to the axis are relative to each other. Since the position is fixed, the misalignment due to the external force received by the housings 17 and 18 and its own weight, and the positional fluctuation in the axial direction are reduced.

Further, since the relative position between the bearing 4 and the seal surface 14a is finished with the processing accuracy of the bearing 4, there is little variation due to the processing tolerance. For this reason, the amount of deformation of the pressure load ring 15 is small, and the seal ring 14 is always within the proper fluctuation range. Therefore, heat generation of the seal 14 causes welding damage to the seal surface 14a and heat of the O-ring 16 is generated. Prevents hardening due to deterioration. Also, oil leakage due to insufficient pressing pressure on the sealing surface is prevented. In particular, when the pressure load ring 15 is baked and integrally joined to the joining partner with an elastic body such as rubber, the positioning of the seal 14 becomes easy.

Further, since the pressure load ring 15 is connected, the O-ring 16 is moved by the intrusion of earth and sand and water 2 from the outside to the surface of the O-ring 16 and the pressure due to the freezing of earth and sand and water in the cold region. Prevents fraudulent seal pressure due to slippage.

Further, in order to prevent seizure of the shaft sealing device and oil leakage due to wear, a seal ring 11a which is a part of the bearing outer ring is combined with a wear resistant composite material to expand the range of application. There is.

[0016]

EXAMPLES Examples will be described with reference to the drawings.
In FIG. 1, when applied to a track roller of a construction machine, a rotary side housing 17 driven by a crawler belt (not shown) and a fixed side housing 18 fixed to a shaft 1 by a pin 5 are internally lubricated by a sealing surface 14a. It prevents oil 3 from leaking to the outside. The bearing 4 fitted in the rotation side housing 17 has a seal ring 11 a integrally formed with the bearing outer ring 11 and is rotating. An O-ring 19 is attached to the outer ring 11 of the bearing to prevent intrusion of earth and sand / water 2 from the outside into each seal portion and prevent the lubricating oil 3 inside from leaking to the outside.

A bush 20 is press-fitted into the rotary side housing 17, and has a radial clearance A while rotating and sliding on the inner surface of the bush 20 with respect to the shaft 1. Further, the bush 20 has a collar 20a for receiving the thrust load of the fixed housing 18, and has a thrust clearance B so that an excessive force due to the dimensional tolerance of the member or thermal expansion is not generated in the sealing surface 14a. .

The bearing 4 holding the fixed side seal ring 14 includes a bearing outer ring 11 and a bearing rolling element 12.
And a bearing inner ring 13. The bearing inner ring 13 includes an O-ring groove 16 a for sealing the fixed-side housing 18 with an O-ring 16, and a fixed-side seal ring 14.
Joint 15 for coupling the elastic load to the pressure load ring 15
There is a.

An O-ring 16 seals the inside and outside of the gap between the fixed housing 18 and the bearing inner ring 13. An external force is applied to the rotary housing 17 and the fixed housing 18, and the displacement in the axial direction and the direction perpendicular to the axis is
Although it fluctuates due to the clearances A and B and the deflection of the shaft 1, this displacement is absorbed by the O-ring 16, so the bearing outer ring 11 and the bearing inner ring 13 are
The relative position is fixed by the bearing rolling elements 12. Therefore, the compression amount of the pressure load ring 15 does not change, so that the pressure of the seal surface 14a formed by the fixed side seal ring 14 and the seal ring 11a can be kept constant.

As a rotary shaft sealing device for an applied machine, the seal ring 11a is optimally integrated with the bearing outer ring 11, and there are the following combinations as means for enhancing the durability of the seal surface due to heat generation. (A) Rotating-side sealing surface 1 with which the fixed-side sealing ring 14 contacts
A material that is harder than the material of the bearing outer ring 11 is attached to 4a. (B) Rotating-side sealing surface 1 with which the fixed-side sealing ring 14 contacts
A non-metallic material such as artificial diamond, which is harder than the material of the bearing outer ring 11, is formed on the surface 4a by crystal forming means. (C) Rotating-side sealing surface 1 with which the fixed-side sealing ring 14 contacts
A metal material harder than the material of the bearing outer ring 11 is formed on the surface 4a by thermal spraying means. (D) Rotating-side sealing surface 1 with which the fixed-side sealing ring 14 contacts
A non-metallic material such as ceramics, which is harder than the material of the bearing outer ring 11, is formed on the surface 4a by baking molding means.

2 and 3 are partial longitudinal sectional views showing another embodiment of the rotary shaft sealing device of the present invention. 2, in order to prevent the stationary side housing 18 of FIG. 1 and the bearing inner ring 13 from slipping due to the force in the rotational direction, the stationary side housing 1
8 and the bearing inner races 13 and 36 constitute a concavo-convex portion having one or more circumferences. 2 (a) is a side view, FIG.
(B) shows a bottom view.

Further, in FIG. 3, the seal ring 11a integrally formed with the bearing outer ring 35 fitted to the rotary side housing 17 driven by the crawler belt (not shown) and the fixed side seal ring 14 constituting the seal surface 14a are A bearing sliding surface 36a is provided between the bearing outer ring 35 and the bearing inner ring 36 that seals the stationary housing 18 with an O-ring 16, and an elastic pressure load ring 15 is provided between the bearing inner ring 36 and the bearing inner ring 36. The rolling bearing of FIG. 1 is a sliding bearing. The same parts as those in FIG. 1 are designated by the same reference numerals. The collar 37 is fixed by a snap ring 38 for ease of assembly. In addition to the above description on the drawings, there is an embodiment in which the relationship between the fixed side and the rotating side of each housing is reversed.

[0023]

EFFECTS OF THE INVENTION Since the present invention is constructed as described above, it provides a rotary shaft sealing device which has the following effects, prevents oil leakage and seizure, and is versatile. .

Even if an external force is applied to the housings 17 and 18, no external force is applied to the bearing 4. The bearing outer ring 11 and the bearing inner ring 13 are the bearing rolling elements 1
Since the relative position is fixed by 2, slippage in the thrust direction can be prevented, and the compression amount of the pressure load ring 15 remains unchanged. Therefore, the pressure of the seal surface 14a formed by the fixed side seal ring 14 and the seal ring 11a is kept constant. Therefore, the variation in the position of the fixed seal ring 14 can be reduced.

Further, even if pressure from the intrusion of sediment / water 2 from the outside or freezing of sediment / water in a cold region is applied, the bearing outer ring 11, bearing rolling element 12, and bearing inner ring 13 of the bearing 4 Is an integral component and is easy to process with high precision. Therefore, variations in relative position can be reduced. In particular, even if pressure is applied by the freezing of earth and sand, water 2, etc. in a cold region, the O-ring 16 can be deformed within the compression range of the rubber, so that an appropriate sealing effect can be provided.

Further, the seal ring 14 and the sliding seal surface 14
The heat generated by a is transferred to the bearing outer ring 11 or 35.
Since heat is transmitted and dissipated by the metal of the rotation side housing 17, the deterioration due to heat can be prevented even at high speed rotation than in the past.

Further, the fixed side housing 18 and the bearing inner races 13 and 36 are provided with the meshing portions 30 at one or more circumferences by the uneven portions, thereby preventing the inner race from slipping in the rotation direction.

Further, since there is little axial positional variation due to the misalignment, it does not matter whether the housing is driven or not driven, so that it is possible to provide a versatile rotary shaft sealing device.

Further, since the seal ring 14 is integrally bonded by baking an elastic body such as rubber to a joint partner, the intrusion of earth and sand and water from the outside into the O-ring surface, and earth and sand and water in cold regions. Since the pressure due to the freezing of the oil can be absorbed only by the O-ring 16, oil leakage due to incorrect seal pressure,
Burn-in can be prevented.

The seal ring 11a integrally formed with the bearing outer ring 11 or 35 has a seal surface 14a which is in contact with the seal ring 14 and has a bearing outer ring 11 or 35.
, A means for laminating a harder metal material than the above material, a means for forming a metal material by thermal spraying, a means for crystallizing a non-metal material such as an artificial diamond, a means for baking and forming a non-metal material such as ceramics. Therefore, the durability of the outer ring of the bearing is enhanced, and the bearing outer ring can be applied to a large-sized shaft sealing device and other rotary shaft sealing devices that require heat resistance.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a first embodiment of a rotary shaft sealing device of the present invention.

FIG. 2 is a partial vertical sectional view showing a third embodiment of the rotary shaft sealing device of the present invention.

FIG. 3 is a partial vertical sectional view showing a second embodiment of the shaft sealing device of the present invention.

FIG. 4 is a vertical cross-sectional view of a shaft sealing device showing a floating seal of the related art.

FIG. 5 is a vertical cross-sectional view of a shaft sealing device showing a conventional end face seal.

[Explanation of symbols]

4 bearings, 11 bearing outer ring, 11a seal ring, 12
Bearing rolling element, 13 bearing inner ring,
13a O-ring groove, 14 seal ring,
14a Sealing surface, 15 Elastic pressure load ring, 16 O-ring, 17 Rotating side (or fixed side) housing, 18 Fixed side (or rotating side) housing, 30 Engagement part,
35 bearing outer ring, 36 bearing inner ring, 36a bearing sliding surface,

Claims (5)

[Claims] 1. A rotation-side housing (1) driven externally
In a rotary shaft sealing device that seals 7) and the fixed housing (18), a bearing that is fitted into the rotary housing (17).
(4) is the bearing outer ring (11) and the bearing rolling element (12)
And the bearing inner ring (13), the bearing inner ring
(13) has an O-ring groove (13a) for sealing the fixed side housing (18) with an O-ring (16), and a bearing inner ring (13).
To the elastic pressure load ring (15).
(a) is provided, and a seal surface (14a) is constituted by the end surface portion of the bearing outer ring (11) and the fixed side seal ring (14). 2. The rotary shaft sealing device according to claim 1,
The bearing (4) to be fitted in the rotating housing (17) is
It consists of the bearing outer ring (35) and the bearing inner ring (36) having a sliding surface (36a) between the bearing outer ring (35). The bearing inner ring (36) has an O ring (16). There is an O-ring groove (13a) for sealing with the fixed side housing (18) and a joint part (15a) for connecting the fixed side seal ring (14) to the elastic pressure load ring (15). A rotary shaft sealing device characterized in that a sealing surface (14a) is constituted by an end surface portion of an outer ring (35) and a fixed side seal ring (14). 3. The rotary shaft sealing device according to claim 1 or 2, wherein the fixed side housing (18) and the bearing inner ring (13).
, 36) are joined together at the meshing part (30). 4. A rotary shaft sealing device, wherein the pressure load ring (15) according to any one of claims 1 and 2 is baked and integrally coupled to a mating partner with an elastic body such as rubber. 5. The integrally formed seal ring (11a) according to claim 1 or 2, wherein the seal ring (14) is in contact with the seal surface.
The rotary shaft sealing device is characterized in that a material harder than the material of the bearing outer ring (11) or (35) is bonded to (14a).