JPH0583541U - Sealing device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a sealing device capable of discharging a foreign substance that has entered into a minute gap from the outside. [Structure] The axis B of the front lid 5 mounted on the axle and the axis B of the seal case 20 and the seal ring 23 provided on the outer ring of the bearing are concentrically arranged at a position substantially horizontal, and An annular groove 8 is provided on the end face, and the tail portion 24 of the seal ring 23 is provided.
Is arranged in the annular groove 8 to form the minute gap D, and the annular guide groove 26 is provided on the outer peripheral surface of the tail portion 24 of the seal ring 23.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sealing device used, for example, for sealing a bearing that holds an axle of a railway vehicle.

[0002]

[Prior Art]

 FIG. 5 shows a conventional sealing device of this type. In the figure, reference numeral 100 denotes an axle as a rotating shaft, and an annular front lid 102 as a rotating ring is attached to the axle 100. An annular groove 103 is provided on the end surface of the front lid 102.

On the other hand, the axle 100 is fitted to an inner ring 105 of a bearing 104, and a seal case 107 as a fixed ring is fitted to an outer ring 106 of the bearing 104. The free end side 108 of the seal case 107 is disposed in the groove 103 and forms a minute gap A having a substantially U-shaped cross section.

An oil seal 109 as a seal ring is fitted and fixed on the inner peripheral side of the seal case 107, and a seal lip 110 thereof comes into contact with a collar ring 111 fixed to the axle 100 to seal the sealing surface. Is forming.

In the above structure, the minute gap A prevents foreign matter such as muddy water, rainwater, and dust from entering from the atmosphere side due to the labyrinth effect. The seal lip 110 also prevents grease from leaking inside the bearing 104 and prevents foreign matter from entering the bearing 104.

[0006]

[Problems to be solved by the device]

 However, in the above-mentioned conventional example, the shape of the minute gap A cannot be made so complicated due to a problem in processing accuracy of the front lid 102 and the seal case 107, and it is possible to prevent intrusion from the outside, especially fluid such as rainwater. The sealing function is inferior.

As a result, the seal lip 110 was worn early due to the frictional resistance with the intruding object, and the durability and the sealing property of the oil seal 109 were significantly reduced.

The present invention is intended to solve the above problems, and an object of the present invention is to provide a sealing device capable of discharging an intruder into a minute gap to the outside.

[0009]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention is arranged such that the axis of a rotary ring mounted on a rotary shaft and the axis of a fixed ring provided on a housing are substantially horizontal, and the end faces of the rotary ring are arranged concentrically. An annular groove is provided on the fixed ring, and the free end side of the fixed ring is arranged in the annular groove to form a minute gap between the rotary ring and the fixed ring, and the fixed ring has a sealing surface on the rotary shaft side. In the sealing device equipped with the seal ring, an annular guide groove is provided on the outer peripheral surface of the fixed ring on the free end side.

[0010]

[Action]

 In the present invention based on the above configuration, the invading substance in the minute gap moves downward along the guide groove by its own weight, and exits from the guide groove at the lowest end of the fixed ring on the free end side and is discharged to the outside.

[0011]

【Example】

 FIG. 1 is a sectional view of a first embodiment in which the present invention is applied to an axle of a railway vehicle. The axle 1 serving as a rotating shaft is arranged with the axis B thereof being substantially horizontal. The axle 1 has a small-diameter portion 2, a medium-diameter portion 3, and a large-diameter portion 4 sequentially from the end side toward the center side.

A male screw (not shown) is formed on the outer peripheral surface of the middle diameter portion 3, and an annular front lid 5 as a rotary ring having a female screw on the inner peripheral surface is fastened and fixed to the middle diameter portion 3. There is. The front lid 5 may be fixed to the intermediate diameter portion 3 by welding or the like.

The front lid 5 has a main body 6 and an outward flange 7 integrally provided on the outer peripheral side of the main body 6. An annular groove 8 having a substantially horizontal depth centered on the axis B is provided on the end face of the outward flange 7 facing the large diameter portion 4 side.

On the other hand, the main body 6 is provided with a plurality of internal threads 9 substantially parallel to the axis B on the same circumference. An annular plate 10 having a substantially L-shaped cross section is attached to the end face of the main body 6 facing the small diameter portion 2 side. The plate 10 is fixed by a screw 11 which is screwed into the female screw 9. A cap 12 is attached to the plate 10 to cover the end surface side of the small diameter portion 2.

The axle 1 is rotatably held by a bearing 13. The bearing 13 has an inner ring 14 into which the large diameter part 4 is fitted and an outer ring 15 as a housing, and a rolling element 16 is interposed between the inner ring 14 and the outer ring 15.

A collar ring 17 is fixed on the outer periphery of the large-diameter portion 4, that is, between the inner ring 14 and the main body 6. The collar ring 17 has an annular collar 18 that extends substantially parallel to the axis B and surrounds the outside of the main body 6.

An annular mounting groove 19 is provided in the outer ring 15 of the bearing 13, and a metal seal cover 20 forming a fixed ring is fitted and fixed to the mounting groove 19 together with a seal ring described later. .. As shown in FIG. 2, the cylindrical portion 21 of the seal case 20 is dimensioned so as to reach the vicinity of the end face of the outward flange 7, and the free end 22 thereof is formed into a hook shape by bending inward.

As shown in FIG. 2, a seal ring 23 made of a rubber-like elastic material is joined to the inner peripheral side of the free end 22. The seal ring 23 has a tail portion 24 as a free end side extending toward the outward flange 7 side substantially in parallel with the axis B, and the tail portion 24 is located in the annular groove 8. The seal case 20 and the seal ring 23 are arranged around the axis B.

In this way, an annular minute gap D having a substantially U-shaped cross section is formed between the outward flange 7 and the tail portion 24. A guide groove 26 is formed on the outer peripheral surface of the tail portion 24 by providing a plurality of annular tail protrusions 25 having an outer diameter that does not contact the outward flange 7 on the outer peripheral surface of the tail portion 24.

Further, a main seal lip 27 and a dust lip 28 are integrally formed on the inner peripheral side of the seal ring 23, and contact the flange 18 to form a seal surface. The sealing surface and the outside E communicate with each other through a minute gap D.

A spring 29 is attached to the back surface of the main seal lip 27, while a metal annular spring cover 30 having a substantially L-shaped cross section is provided on the inner peripheral side of the cylindrical portion 21. It is fitted.

In the above structure, the axle 1 rotates, and the vicinity of the rolling elements 16 is lubricated with grease (not shown). The main seal lip 27 prevents grease from leaking to the outside E.

On the other hand, when foreign matter such as muddy water, rainwater, and dust existing in the outside E tries to enter the minute gap D, the labyrinth effect seals. In the unlikely event that a foreign substance enters the minute gap D as shown in FIG. 4A, the intruding substance F travels along the guide groove 26 and moves downward due to its own weight. ), It falls from the guide groove 26 by its own weight and is discharged to the outside E.

Therefore, it is possible to prevent the intruding material F from entering the sealing surfaces of the main lip 27 and the dust lip 28, and improve the durability and sealing performance of the seal ring 23.

In this embodiment, since the seal case 20 and the seal 23 are integrally formed by vulcanization, that is, an oil seal type, the number of parts is small and the structure is simple. Further, the protrusion 25 and the groove 26 of the tail portion 24 can be formed simultaneously with the molding of the seal ring 23. Therefore, the manufacturing cost can be reduced.

FIG. 3 shows a second embodiment. Since the seal case 31 as a fixed ring fixed to the outer ring 15 is centered on the shaft center B, if the free end 32 of the seal case 31 is arranged in the annular groove 8 of the front lid 5, the first embodiment will be described. The minute gap D can be formed similarly to. A plurality of guide grooves 33 formed by cutting are provided on the outer peripheral surface of the free end 32.

On the other hand, the spring cover 30 is fitted and fixed to the inner peripheral side of the cylindrical portion 34 of the seal case 31. An oil seal 35 as a seal ring is fitted on the inner circumference of the spring cover 30. The oil seal 35 has a metallic ring 36 and a rubber-like elastic seal body 37, and a main seal lip 38 and a dust lip 39 are integrally provided on the inner peripheral side of the seal body 37.

Also in this embodiment, the main seal lip 38 and the dust lip 39 contact the collar 18 to form a sealing surface. Then, the foreign matter that has entered the minute gap D travels downward in the guide groove 33 and is discharged to the outside. Therefore, the same effect as the first embodiment can be obtained.

The present invention can be applied to not only railway vehicles but also pumps, agitators, construction machines, and the like. The seal ring may be an O-ring, V packing, lip packing, or the like.

[0030]

[Effect of the device]

 Since the present invention is configured as described above, when a foreign substance enters the minute gap, the intruding substance moves downward along the guide groove by its own weight and is guided at the lowermost portion of the free end of the fixed ring. It falls from the groove by its own weight and is discharged to the outside.

Therefore, it is possible to prevent an intruding substance from reaching the sealing surface of the seal ring, and it is possible to improve the durability and sealing property of the sealing ring.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment in which the present invention is applied to a bearing seal for an axle of a railway vehicle.

FIG. 2 is a cross-sectional view in the vicinity of a minute gap, which is a main part of FIG.

FIG. 3 is a cross-sectional view of essential parts of a second embodiment in which the structures of the seal case and the seal ring are changed.

4 (A) and 4 (B) are enlarged cross-sectional views showing an operation of intruding and ejecting a foreign matter into a minute gap in the first embodiment.

FIG. 5 is a half sectional view showing a conventional example.

[Explanation of symbols]

 1 Axle (rotating shaft) 2 Small diameter part 3 Medium diameter part 4 Large diameter part 5 Front lid (rotating ring) 6 Main body 7 Outward flange 8 Groove 9 Female screw 10 Plate 11 Screw 12 Cap 13 Bearing 14 Inner ring 15 Outer ring (housing) 16 Rolling element 17 Collar ring 18 Collar 19 Mounting groove 20,31 Seal case (fixed ring) 21,34 Inner cylinder part 22 Free end 23 Seal ring (fixed ring) 24 Tail part 25 Protrusion 26 Guide groove 27,38 Main seal lip 28,39 dust lip 29 spring 30 spring cover 32 free end 33 guide groove 35 oil seal (seal ring) 36 metal ring 37 seal body B shaft center E external D small gap F intruder

Claims (1)

[Scope of utility model registration request] 1. A rotary ring to be mounted on a rotary shaft and a fixed ring provided on the housing are arranged concentrically with each other at a substantially horizontal position, and an annular groove is provided on an end face of the rotary ring. The free end side of the fixed ring is arranged in the annular groove to form a minute gap between the rotary ring and the fixed ring, and the fixed ring is provided with a seal ring that forms a seal surface on the rotary shaft side. In the sealing device, an annular guide groove is provided on the outer peripheral surface of the fixed ring on the free end side.