Bearing

Abstract

The invention provides a bearing which comprises an inner ring, an outer ring and an oil seal, the outer ring is arranged in the circumferential direction of the inner ring in a sleeving mode, and a groove and a roller groove are formed between the outer ring and the inner ring; wherein the groove comprises a main body groove and an extension groove communicated with the main body groove, and the extension groove is closer to the roller groove than the main body groove; the oil seal comprises an oil seal body and self-tightening rings connected to the oil seal body, a plurality of sealing lips distributed in the axial direction of the oil seal body are arranged on the first sealing face of the oil seal body, and the multiple self-tightening rings correspond to the sealing lips in the radial direction in a one-to-one mode so as to apply pressure to the sealing lips. The oil seal is embedded in the groove, and at least one set of sealing lips and the self-tightening ring are located in the extending groove. By means of the arrangement, the grooves are designed in a special shape, namely, the grooves extend towards the inner side to form the extending grooves, meanwhile, the oil seals are designed in a special shape, the multiple sets of sealing lips and the self-tightening rings are arranged in the axial direction, the sealing interval of the bearing is equivalently extended, and the problem that in the prior art, a bearing for the harmonic reducer is prone to sealing failure is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bearings, in particular to a bearing. BACKGROUND

[0002] For most bearings, sealing is an important performance. At present, a skeleton oil seal is only provided in the cross roller bearing structure commonly used in harmonic reducers, so that the sealing effect only relies on the skeleton oil seal. This leads to the phenomenon of oil seepage and leakage after long-time operation of the harmonic reducer. In addition, the working condition of the harmonic reducer is relatively complex, and sometimes the phenomenon of oil seepage and leakage is more serious, which can cause sealing failure. SUMMARY

[0003] Therefore, the present application provides a bearing to solve the problem of easy sealing failure of the bearing for the harmonic reducer in the prior art.

[0004] In order to achieve the above purpose, the present application provides the following technical scheme:

[0005] A bearing, comprising an inner ring, an outer ring and an oil seal, the outer ring is circumferentially sleeved on the inner ring, and a groove and a roller groove are provided between the outer ring and the inner ring; wherein,

[0006] The groove comprises a main groove and an extension groove communicated with the main groove, and the extension groove is closer to the roller groove than the main groove;

[0007] The oil seal comprises an oil seal body and a self-tightening ring connected to the oil seal body, a first sealing surface of the oil seal body is provided with a plurality of sealing lips arranged along the axial direction of the oil seal body, and the self-tightening ring is provided with a plurality of self-tightening rings corresponding to each sealing lip in the radial direction to apply pressure to each sealing lip;

[0008] The oil seal is embedded in the groove, and at least one group of the sealing lips and the self-tightening ring are located in the extension groove.

[0009] Optionally, the sealing lips are adjacent to each other to form a containing groove capable of containing lubricating grease.

[0010] Optionally, a dust lip is provided on the oil seal body, and the dust lip is located on the first sealing surface and is away from the roller groove compared with all the sealing lips.

[0011] Optionally, the circumferential direction of the dust lip is provided with a missing groove.

[0012] Optionally, the first sealing surface is an inner annular surface of the oil seal body, and the self-tightening ring is a hoop spring.

[0013] Optionally, the second sealing surface of the oil seal body is a flat surface or a wavy surface, one of the first sealing surface and the second sealing surface is an outer annular surface of the oil seal body, and the other is an inner annular surface.

[0014] Optionally, the oil seal body comprises:

[0015] an outer layer;

[0016] a diaphragm arranged radially inward of the outer layer and spaced apart from the outer layer;

[0017] a bottom layer connected between the outer layer and the diaphragm;

[0018] wherein a skeleton is arranged in the outer layer and the bottom layer, and the first sealing surface is a surface of the diaphragm away from the outer layer.

[0019] Optionally, a self-tightening ring groove is arranged on a surface of the diaphragm close to the outer layer, an edge of the self-tightening ring groove is provided with a protective lip, the self-tightening ring is embedded in the self-tightening ring groove, and the protective lip limits the self-tightening ring in the self-tightening ring groove.

[0020] Optionally, a cross section of the sealing lip is an obtuse angle.

[0021] Optionally, a sealing groove is further arranged between the outer ring and the inner ring, the sealing groove is located between the groove and the roller groove and / or on a side of the roller groove away from the groove;

[0022] a star-shaped sealing ring or an O-shaped sealing ring is arranged in the sealing groove.

[0023] The bearing provided in the present application includes an inner ring, an outer ring and an oil seal, the outer ring is arranged on the circumference of the inner ring, and a groove and a roller groove are provided between the outer ring and the inner ring; wherein the groove includes a main groove and an extension groove connected to the main groove, and the extension groove is closer to the roller groove than the main groove; the oil seal includes an oil seal body and a self-tightening ring connected to the oil seal body, the first sealing surface of the oil seal body is provided with a plurality of sealing lips arranged along the axial direction of the oil seal body, and the self-tightening ring is provided with a plurality of sealing lips respectively corresponding to each sealing lip in the radial direction to apply pressure to each sealing lip respectively; the oil seal is embedded in the groove, and at least one group of sealing lips and self-tightening rings are located in the extension groove. With this arrangement, since the roller groove is where the roller is located, the oil seal at the groove serves as a sealing barrier, and the self-tightening ring provides pressure to the sealing lip. The total radial force of the sealing lip is jointly given by the elastic force of the oil seal and the self-tightening ring to achieve sealing. The conventional groove is designed to be special-shaped, that is, it is extended inward to form an extension groove located between the main groove and the roller groove. At the same time, the oil seal is also designed to be special-shaped, and multiple groups of sealing lips and self-tightening rings are arranged axially, and at least one group is in the extension groove. This is equivalent to extending the sealing range of the bearing, and also realizes multi-pass sealing, reduces the sealing pressure of the oil seal, and ensures sufficient lubrication of the bearing, thereby reducing the probability of oil seepage and leakage, and solving the problem of easy sealing failure of bearings used in harmonic reducers in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0025] Figure 1 A schematic diagram of the overall structure of a bearing provided in an embodiment of the present application;

[0026] Figure 2 A partial cross-sectional schematic diagram of a bearing provided in an embodiment of the present application;

[0027] Figure 3 for Figure 2 Magnified cross-sectional view;

[0028] Figure 4 A partial cross-sectional schematic diagram of an oil seal provided in an embodiment of the present application;

[0029] Figure 5 A schematic cross-sectional view of an oil seal provided in an embodiment of the present application;

[0030] Figure 6 This is an overall schematic diagram of the oil seal provided in an embodiment of the present application.

[0031] existFigures 1-6 In the drawings:

[0032] 1, oil seal; 2, inner ring; 3, outer ring; 4, groove; 5, roller groove;

[0033] 11, oil seal body; 12, hoop spring; 13, sealing lip; 14, dust lip; 15, accommodating groove; 16, missing groove; 17, lip protector; 18, self-tightening ring groove;

[0034] 41, main groove; 42, extension groove;

[0035] 111, outer layer; 112, diaphragm; 113, bottom layer; 114, skeleton. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0037] The oil seal 1 is a component designed in a ring shape, installed between relatively rotating mechanical parts, and has a function of separating oil or grease on the inner side from dirt, dust, water, etc. on the outer side.

[0038] As shown in the drawings, Figures 1-6 The present application provides a bearing suitable for a speed reducer, in particular a harmonic reducer, which comprises an inner ring 2, an outer ring 3, and an oil seal 1. The outer ring 3 is sleeved around the inner ring 2 in the circumferential direction, and a groove 4 and a roller groove 5 are arranged between the inner annular surface of the outer ring 3 and the outer annular surface of the inner ring 2. The groove 4 is an open groove at the end, formed by partial missing of the inner annular surface of the outer ring 3. The groove 4 comprises a main groove 41 and an extension groove 42 in communication with the main groove 41. The extension groove 42 is closer to the roller groove 5 than the main groove 41, that is, the groove 4 is in a stepped shape. The roller groove 5 contains a roller structure. The oil seal 1 comprises an oil seal body 11 and a self-tightening ring connected to the oil seal body 11. A first sealing surface of the oil seal body 11 is provided with a plurality of sealing lips 13 arranged in the axial direction of the oil seal body 11. The sealing lips 13 protrude relative to the oil seal body 11. The self-tightening ring is provided with a plurality of self-tightening rings corresponding to the sealing lips 13 in the radial direction, respectively, to apply pressure to the sealing lips 13, respectively. The oil seal 1 is embedded in the groove 4, and at least one group of sealing lips 13 and self-tightening rings are located in the extension groove 42. The oil seal body 11 abuts against the extension groove 42 in the axial direction. The sealing lips 13 and the self-tightening rings can be two groups, three groups, or even more groups.

[0039] Thus, the oil seal 1 is arranged as a sealing barrier at the groove 4, and the pressure is provided from the self-tightening ring to the sealing lip 13, and the total radial force of the sealing lip 13 is provided by the elastic force of the oil seal 1 and the self-tightening ring, so that the sealing is realized. The conventional groove 4 is designed as a special shape, that is, the inner side is designed to extend, so that the extension groove 42 is formed between the main groove 41 and the roller groove 5, and the oil seal 1 is also designed as a special shape, and a plurality of groups of sealing lips 13 and self-tightening rings are arranged in the axial direction, and at least one group is arranged in the extension groove 42, so that the sealing interval of the bearing is extended, and the multi-sealing is realized, the sealing pressure of the oil seal 1 is reduced, and the full lubrication of the bearing is ensured, so that the probability of oil leakage is reduced, and the problem of sealing failure of the bearing for the harmonic reducer in the prior art is solved.

[0040] Moreover, different from the conventional sealing ring additionally arranged on the bearing in the prior art, the oil seal 1 is designed in different structures in the application to compensate for the sealing deficiency of the bearing, and the fixed thinking and technical prejudice are overcome. Moreover, compared with the conventional additional sealing ring, the bearing provided in the application is not additionally assembled, and the assembly process is not additionally increased, and the assembly complexity of the bearing is not increased. Specifically, the outer ring 3 of the bearing is fixed on a tool, is screwed, and is locked in a mounting hole. The inner ring 2 of the bearing is concentrically arranged with the outer ring 3 of the bearing, and the middle part is connected by the roller end face. The oil seal 1 is arranged at the groove 4 of the end face of the inner ring 2 and the outer ring 3 of the bearing, and is pressed into the groove 4 by using a pressure tool.

[0041] Further, the containing grooves 15 capable of containing the lubricating grease are formed between the adjacent sealing lips 13 in the axial direction. Thus, the containing grooves 15 can contain the lubricating grease, and form a lubricating cavity after the oil seal 1 is assembled with the inner ring 2 and the outer ring 3, so that the friction resistance and the starting resistance are reduced, the dry friction between the oil seal 1 and the inner ring 2 and the outer ring 3 in the initial stage is avoided, the oil seal 1 is prevented from being pulled and worn in the initial stage, and the long-term and effective sealing of the oil seal 1 in the later stage is ensured.

[0042] In addition, the transverse section of the sealing lip 13 is preferably an obtuse angle, so that the sealing lip 13 has stronger wear resistance and stronger extrusion resistance, and has better sealing effect.

[0043] In a specific embodiment, the dust lip 14 is arranged on the oil seal body 11, is located on the first sealing surface, and is away from the roller groove 5 compared with all the sealing lips 13, or is located on the outermost side in the axial direction. Thus, the dust lip 14 can isolate the dirt, dust and water on the outside, and provide a good sealing environment for the sealing lip 13, so that the wear of the sealing lip 13 is reduced.

[0044] Further, the dust-proof lip 14 is provided with a concave missing groove 16 in the circumferential direction. The missing groove 16 can improve the deformation ease of the dust-proof lip 14, so that the dust-proof lip 14 is easy to deform, and the friction resistance at the dust-proof lip 14 after installation is reduced.

[0045] In another specific embodiment, the first sealing surface is the inner annular surface of the oil seal body 11, and the self-tightening ring is the hoop spring 12. In this way, the hoop spring 12 has a tendency to contract radially inward, can generate a radially inward pressure on the sealing lip 13, and acts on the first sealing surface. When the oil seal 1 is installed in the groove 4, the pressure of the sealing lip 13 and the contraction force of the hoop spring 12 generate a certain radial tightness on the inner ring 2. After a period of operation, the pressure will decrease rapidly, and the hoop spring 12 can compensate the self-tightening force of the oil seal 1 at any time.

[0046] In addition, in some cases, the self-tightening ring can also be a rubber ring or a silica gel ring with radial elastic deformation capability.

[0047] In another preferred embodiment, the second sealing surface of the oil seal body 11 is a flat surface or a wavy surface, one of the first sealing surface and the second sealing surface is the outer annular surface of the oil seal body 11, and the other is the inner annular surface. The first sealing surface is the inner annular surface of the oil seal body 11, and the second sealing surface is the outer annular surface of the oil seal body 11 as shown in the figure.

[0048] In a specific embodiment, the oil seal body 11 includes an outer layer 111, a bottom layer 113, and a diaphragm 112: the diaphragm 112 is located radially inward of the outer layer 111 and is spaced apart from the outer layer 111; the bottom layer 113 is connected between the outer layer 111 and the diaphragm 112, and is the part of the oil seal body 11 exposed to the outside; wherein the outer layer 111 and the bottom layer 113 are provided with an L-shaped skeleton 114 made of metal, the first sealing surface is the side of the diaphragm 112 away from the outer layer 111, and the outer layer 111, the bottom layer 113 and the diaphragm 112 are all made of elastic material and are vulcanized and formed on the skeleton 114. The skeleton oil seal thus formed can effectively bear the sealing function and also serve as a support.

[0049] Further, the diaphragm 112 is provided with a self-tightening ring groove 18 on the side close to the outer layer 111, the edge of the self-tightening ring groove 18 is provided with a guard lip 17, the self-tightening ring is embedded in the self-tightening ring groove 18, and the guard lip 17 limits the self-tightening ring in the self-tightening ring groove 18, thereby enhancing the assembly stability of the self-tightening ring on the oil seal body 11.

[0050] In another optional embodiment, a sealing groove is further provided between the outer ring 3 and the inner ring 2, and is located between the groove 4 and the roller groove 5 and / or on the side of the roller groove 5 away from the groove 4; a star-shaped sealing ring or an O-shaped sealing ring is arranged in the sealing groove. In this way, a sealing barrier is further arranged between the oil seal 1 and the roller groove 5, thereby further improving the sealing reliability of the bearing.

[0051] In one embodiment, the bearing described above can be a cross-roller bearing suitable for use in a harmonic reducer.

[0052] The above describes the basic principles of the present application in conjunction with specific embodiments, but it should be noted that the advantages, benefits, effects and the like mentioned in the present application are only examples and are not limiting, and these advantages, benefits, effects and the like cannot be considered as necessary for each embodiment of the present application. In addition, the above specific details disclosed are only for the purpose of example and understanding, and are not limiting, and the above details do not limit the present application to be necessarily implemented with the above specific details.

[0053] The block diagrams of the devices, apparatuses, equipment, systems involved in the present application are only illustrative examples and are not intended to require or imply the connection, arrangement, configuration as shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, equipment, systems can be connected, arranged, configured in any manner. Words such as "include", "contain", "have" and the like are open-ended words, mean "including but not limited to", and can be used interchangeably. The words "or" and "and" used herein mean the word "and / or", and can be used interchangeably unless the context clearly indicates otherwise. The word "such as" used herein means the phrase "such as but not limited to", and can be used interchangeably.

[0054] It should also be noted that in the devices, equipment and methods of the present application, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be considered as equivalent solutions of the present application.

[0055] The above description of the disclosed aspects is provided so that any person skilled in the art can make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of the present application. Thus, the present application is not intended to be limited to the aspects shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0056] It should be understood that the adjectives "first", "second", "third", "fourth", "fifth" and "sixth" used in the embodiments of the present application are only used for clearer description of the technical solutions, and cannot be used to limit the protection scope of the present application.

[0057] The above description has been given for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, one skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A bearing, characterized by, The oil seal (1) is embedded in the groove (4), and at least one group of the sealing lips (13) and the self-tightening ring are located in the extension groove (42). The containing grooves (15) capable of containing lubricating grease are formed between adjacent sealing lips (13). The oil seal body (11) is provided with a dust lip (14) located on the first sealing surface and farther away from the roller groove (5) than all the sealing lips (13). The circumferential direction of the dust lip (14) is provided with a missing groove (16).

2. The bearing of claim 1, wherein The first sealing surface is the inner annular surface of the oil seal body (11), and the self-tightening ring is a hoop spring (12).

3. The bearing of claim 1, wherein The second sealing surface of the oil seal body (11) is a flat surface or a wavy surface, one of the first sealing surface and the second sealing surface is the outer annular surface of the oil seal body (11), and the other is the inner annular surface.

4. The bearing of claim 3, wherein The oil seal body (11) comprises:

5. The bearing of claim 1, wherein an outer layer (111); 6. The bearing of claim 1, wherein a diaphragm (112) located on the radially inner side of the outer layer (111) and spaced apart from the outer layer (111); 7. The bearing of claim 1, wherein a bottom layer (113) connected between the outer layer (111) and the diaphragm (112); wherein the outer layer (111) and the bottom layer (113) are provided with a framework (114), and the first sealing surface is a side of the diaphragm (112) away from the outer layer (111). The diaphragm (112) is provided with a self-tightening ring groove (18) on a side close to the outer layer (111), the edge of the self-tightening ring groove (18) is provided with a guard lip (17), the self-tightening ring is embedded in the self-tightening ring groove (18), and the guard lip (17) limits the self-tightening ring in the self-tightening ring groove (18). The cross section of the sealing lip (13) is obtuse. The outer ring (3) and the inner ring (2) are further provided with a sealing groove located between the groove (4) and the roller groove (5) and / or located on the side of the roller groove (5) away from the groove (4); 8. The bearing of claim 7, wherein, The sealing groove is provided with a star-shaped sealing ring or an O-shaped sealing ring.

9. The bearing of claim 1, wherein, ​ 10. The bearing of claim 1, wherein ​ ​

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