Oil seal

Abstract

Provided is an oil seal which improves the retentivity of a lubricant. An oil seal (1) is provided with a side lip (14) extending in the axial direction and in contact with a surface of a rotating body (rotating shaft (2)) in the radial direction, and a plurality of recesses (16) are provided in the surface of the side lip (14) in contact with the rotating body (2) so as to be separated from each other in the circumferential direction and the radial direction. The plurality of recesses (16) are discontinuous, so that the lubricant is blocked at the opening edges of the recesses (16), and the lubricant is difficult to flow out from the plurality of recesses (16).

Description

Technical Field

[0001] This utility model relates to oil seals. Background Technology

[0002] For example, Patent Document 1 describes a configuration in which "a parallel groove is provided on the side of the sealing device's lip".

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 4280903 (Japanese Unexamined Patent Application No. 2004-263797) Utility Model Content

[0006] The problem to be solved by the utility model

[0007] In the aforementioned Patent Document 1, since the parallel groove is continuous in the circumferential direction of the side lip, there is a concern that the lubricant such as grease applied in the parallel groove may be pulled in the circumferential direction with the rotation of the shaft and thus flow out of the parallel groove.

[0008] In view of this situation, the purpose of this invention is to provide an oil seal that improves the retention of lubricant.

[0009] Technical solutions for solving the problem

[0010] The oil seal of this invention has a side lip extending in the axial direction and contacting a surface in the rotating body along the radial direction. The side lip is characterized in that the surface in contact with the rotating body is provided with a plurality of recesses in a state of separation from each other in the circumferential and radial directions.

[0011] According to this configuration, although the lubricant applied and filled in the multiple recesses on the inner circumferential surface of the side lip is pulled along with the rotation of the rotating body, the lubricant is blocked at the opening edge of each recess because the multiple recesses are separated from each other, and the lubricant is difficult to flow out from the multiple recesses separately.

[0012] As a result, the lubricant retention of each of the plurality of recesses is improved, thus reducing the frictional resistance of the surface sliding relative to the rotating body in the side lip (also called the sliding surface), and improving the wear resistance of the sliding surface.

[0013] Effects of the utility model

[0014] According to this invention, an oil seal with improved lubricant retention can be provided. Attached Figure Description

[0015] Figure 1This is a top cross-sectional view showing one embodiment of the oil seal of this utility model.

[0016] Figure 2 This is a front view showing the inner circumferential surface of the lateral lip.

[0017] Figure 3 The diagram shows an enlarged view of the contact area between the side lip and the upright wall of the rotating shaft. Detailed Implementation

[0018] Hereinafter, preferred embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.

[0019] Figures 1 to 3 An embodiment of the present invention is shown. The oil seal 1 shown in the figure is mounted in a non-rotating state on a fixed ring (not shown) arranged in a non-contact manner on the outer periphery of the rotating shaft 2, and is configured such that a main lip 12, a secondary lip 13, and a side lip 14 are integrally provided on the main body 11.

[0020] A large-diameter portion 21 extending radially outward is provided at a predetermined position in the axial direction of the rotating shaft 2.

[0021] The main body 11 has the following shape: an annular plate portion 11b is integrally connected to one end of the cylindrical portion 11a in the radially inward direction. It should be noted that although the main body 11 is not shown in detail, it is, for example, a component made by vulcanizing and bonding a rubber-like elastic material to a metal core.

[0022] The main lip 12, the secondary lip 13, and the lateral lip 14 are formed of a rubber-like elastic material.

[0023] The main lip 12 is configured to extend obliquely inward from the inner diameter side of the annular plate portion 11b of the main body 11, thereby inhibiting or preventing the flow of lubricant (grease or oil, etc., omitted from the figure) present in the space sealed by the oil seal 1 (referred to as the sealing space) to the secondary lip 13 and the side lip 14, and then to the outer space.

[0024] The front end portion of the main lip 12 has a triangular cross-sectional shape that is sharp towards the inner diameter side, and a spring ring 15 is fitted on its outer peripheral surface to press the front end portion against the outer peripheral surface of the rotating shaft 2.

[0025] The side lip 14 and the secondary lip 13 are formed to be inclined from the inner diameter side of the main body 11 to the outer side, so as to suppress or prevent foreign objects such as moisture and dust from entering the main lip 12 side and thus the sealed space.

[0026] The main lip 12 and the secondary lip 13 are in contact with the outer peripheral surface of the rotating shaft 2 under a specified pressure, thus becoming flexed. The side lip 14 is in contact with the upright wall surface that rises radially outward at the large diameter portion 21 of the rotating shaft 2 under a specified pressure, thus becoming flexed.

[0027] And, as Figure 2 As shown, a plurality of recesses 16 are provided on the inner circumferential surface of the side lip 14.

[0028] Multiple recesses 16 are each formed in a rhomboid shape and are arranged at certain intervals in the circumferential and radial directions of the inner circumferential surface. It should be noted that the multiple recesses 16 are arranged in an alternating pattern in the circumferential and radial directions.

[0029] Furthermore, when shipping the oil seal 1 after its manufacture, a lubricant such as grease is applied to the surfaces of the main lip 12, the secondary lip 13, and the side lip 14, thereby filling the recess 16 with lubricant.

[0030] When the oil seal 1 with such a structure is actually assembled in the application area, the main lip 12 and the secondary lip 13 will contact the outer peripheral surface of the rotating shaft 2 with a specified pressure, and the inner peripheral surface of the side lip 14 will contact the upright wall surface of the rotating shaft 2 with a specified pressure.

[0031] When rotating axis 2 in this state, as follows: Figure 3 As shown, although the lubricant applied and filled in the multiple recesses 16 on the inner peripheral surface of the side lip 14 is pulled by the rotating shaft 2, the lubricant is blocked at the opening edge of each recess 16 because the multiple recesses 16 are separated from each other, and the lubricant is difficult to flow out from the multiple recesses 16 separately.

[0032] As described above, according to the embodiment of the present invention, the lubricant retention of each of the plurality of recesses 16 at the side lip 14 of the oil seal 1 is improved, thus the frictional resistance of the inner circumferential surface of the side lip 14 sliding relative to the upright wall surface at the large diameter portion 21 of the rotating shaft 2 is reduced, and the wear resistance of the inner circumferential surface is improved.

[0033] As a result, the sealing performance of oil seal 1 can be maintained for a long time, which contributes to the improvement of reliability.

[0034] It should be noted that this utility model is not limited to the above-described embodiments, but can be appropriately modified within the scope of the claims and within the scope equivalent to that scope.

[0035] (1) In the above embodiment, the structure of the auxiliary lip 13 can be eliminated.

[0036] (2) In the above embodiments, the shape of the main body 11 and the main lip 12 is not particularly limited.

[0037] (3) In the above embodiments, the shape of the recess 16 is not particularly limited and can be circular, square, etc.

[0038] Industrial applicability

[0039] This invention can be appropriately applied to oil seals.

[0040] [Label Explanation]

[0041] 1. Oil seal;

[0042] 11 main bodies;

[0043] 11a Cylindrical section;

[0044] 11b Annular plate portion;

[0045] 12 main lip;

[0046] 13 pairs of lips;

[0047] 14. Lateral lips;

[0048] 15 spring coils;

[0049] 16 recesses;

[0050] 2 rotating axes;

[0051] 21. Large diameter section.

Claims

1. An oil seal having a side lip extending in the axial direction and contacting a surface radially within a rotating body, characterized in that, The surface of the side lip that contacts the rotating body is provided with a plurality of recesses that are separated from each other in the circumferential and radial directions.

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