Bearing seal

Abstract

In a bearing seal for preventing electric corrosion of a rolling bearing, energization resistance is reduced, energization stability is improved, and manufacturing becomes easy. The conductive fiber (5) is integrated with a surface layer portion on one surface side of the elastic body (4), and a portion of the conductive fiber (5) is exposed from the surface. A portion of the conductive fibers (5) exposed from the surface of the outer peripheral portion (8) of the elastic body (4) is in contact with the outer ring (11), and a portion of the conductive fibers (5) exposed from the surface of the inner peripheral portion (9) of the elastic body (4) is in contact with the inner ring (12). Since the conductive fibers (5) are integrated with the surface layer part of the elastic body (4), the possibility that the conductive fibers (5) are peeled off from the elastic body (4) is very small. Since the conductive fibers (5) exposed from the surface of the elastic body (4) are in sliding contact with the inner ring (12), the conduction resistance is small, and the contact for conduction is stable. The conductive fiber (5) is integrated with the surface layer part of the elastic body (4), and a part of the conductive fiber (5) is exposed from the surface, so that manufacturing is not difficult.

Description

Technical Field

[0001] This invention relates to bearing seals for preventing electrolytic corrosion of rolling bearings. Background Technology

[0002] For example, in motors and reducer units of electric vehicles, as well as inverter-driven motors other than electric vehicles, current sometimes leaks and flows to the rotating shaft. In this case, in the rolling bearings supporting the rotating shaft, the lubricating oil film is sometimes broken, and current flows between the outer and inner rings, causing damage to the rolling surfaces of the rolling elements due to electric arcing.

[0003] As a bearing seal to prevent electrolytic corrosion of such rolling bearings, there are bearing seals provided with conductive elements for making the outer ring and inner ring conductive (for example, see Patent Documents 1 and 2).

[0004] The bearing seal (seal A) in Patent Document 1 has an elastomer B and a reinforcing member 2, and a conductive member 3, which serves as the aforementioned conductive member, is embedded therein. Figure 1 ) or attachment ( Figure 2 Within the elastic body B, a conductive element 3 is connected to the fitting portion A1 that engages with the outer ring 1b and the sliding contact portion A2 that slides in contact with the inner ring 1a. The conductive element 3 can be a wire, sheet, or foil, etc.

[0005] The bearing seal (sealing assembly 04) of Patent Document 2 has a seal 05 consisting of an elastomer body 08 and a reinforcing member 09. An annular conductive member 14, serving as the conductive element, is adhered to the seal 05. The outer diameter side of the conductive member 14 contacts the outer ring 02, and the inner diameter side of the conductive member 14 slides in contact with the inner ring 03 (FIG.1). The conductive member 14 is a component formed by embedding a conductive fiber fabric composed of carbon fiber, carbon fiber derivatives, metal fibers, or filled polymer fibers into an elastic matrix; that is, a conductive elastomer.

[0006] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 62-106125 Patent Document 2: US Patent No. 11,493,133 Summary of the Invention

[0007] The technical problem that the invention aims to solve In the case of the bearing seal in Patent Document 1, which has a structure in which a conductive element such as a wire, sheet, or foil is embedded in an elastomer, it is very difficult to manufacture the conductive element so that it passes radially through the elastomer, protrudes from a predetermined position in the elastomer, and reliably slides in contact with the inner ring. In the case of the bearing seal in Patent Document 1, where the conductive element is embedded or attached to the elastomer, the conductive element may peel off from the elastomer because a boundary is formed between the conductive element and the elastomer.

[0008] In the case of a bearing seal in which a conductive elastomer slides in the inner ring, as in Patent Document 2, the carbon fiber or the like embedded in the elastomer is energized, thus increasing the resistance to energization. Furthermore, in the presence of a lubricant (grease, oil, etc.), an oil film is formed on the sliding surface between the conductive elastomer and the inner ring, making the contact between the conductive elastomer and the inner ring for energization unstable.

[0009] The object of the present invention is to reduce the electrical resistance and improve the electrical stability in a bearing seal for preventing electrolytic corrosion of rolling bearings, and to make manufacturing easier.

[0010] This means is used to solve technical problems. The first aspect of the invention discloses a bearing seal for a rolling bearing comprising an outer ring, an inner ring, and rolling elements, and includes an annular sealing ring having an elastomer made of rubber material. Conductive fibers are integrally formed on a surface portion of one surface of the elastomer, with a portion of the conductive fibers exposed from the surface. The conductive fibers exposed from the outer periphery of the elastomer contact the outer ring, and the conductive fibers exposed from the inner periphery of the elastomer contact the inner ring.

[0011] A second aspect of the present invention provides a bearing seal for a rolling bearing comprising an outer ring, an inner ring, and rolling elements, and includes an annular sealing ring, wherein the sealing ring has: a core having an engaging portion that engages with the outer ring; and an elastomer that engages with the core. Conductive fibers are integrally formed on a surface portion of one surface side of the elastomer, a portion of which is exposed from the surface. The conductive fibers exposed from the outer periphery of the elastomer contact the core, and the conductive fibers exposed from the inner periphery of the elastomer contact the inner ring.

[0012] Invention Effects As described above, conductive fibers are integrally formed on the surface layer of one side of the elastomer in the bearing seal of the present invention, thus minimizing the possibility of the conductive fibers peeling off from the elastomer. Furthermore, the conductive fibers exposed from the surface of the elastomer slide in contact with the inner ring, thereby reducing the resistance to current transfer and preventing the formation of an oil film as in the case of a conductive elastomer sliding against the inner ring in the presence of lubricant, thus ensuring stable contact for current transfer. Moreover, when the conductive fibers are integrally formed with the surface layer of one side of the elastomer in the bearing seal, allowing a portion of the conductive fibers to protrude from the surface, the conductive fibers exist only in the surface layer of the elastomer, where their position is relatively easy to control, thus eliminating manufacturing difficulties and simplifying the manufacture of the bearing seal. Attached Figure Description

[0013] Figure 1 This is a partially enlarged longitudinal sectional view of a rolling bearing equipped with a bearing seal according to an embodiment of the present invention.

[0014] Figure 2 It means Figure 1 A partially enlarged longitudinal sectional view of the bearing seal of one of the rolling bearings.

[0015] Figure 3 This is a schematic diagram showing a conductive texture formed by integrating fabric-like conductive fibers with the surface layer of an elastomer.

[0016] Figure 4 This is a schematic diagram showing an enlarged cross-section of the aforementioned conductive texture.

[0017] Figure 5 This is a schematic diagram showing a conductive texture formed by integrating non-woven conductive fibers with the surface layer of an elastomer.

[0018] Figure 6 This is a partially enlarged longitudinal sectional view showing the bearing seal of the first modified example.

[0019] Figure 7 This is a partially enlarged longitudinal sectional view showing the area around the bearing seal in the second modified example.

[0020] Figure 8 This is a partially enlarged longitudinal sectional view showing the bearing seal in the third modified example. Detailed Implementation

[0021] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0022] In this specification, the direction parallel to the direction of the rotation center axis of the rolling bearing is referred to as the "width direction" (for example, see reference). Figure 1 Arrow B), the direction orthogonal to the direction of the rotation center axis is called "radial" (e.g., refer to...). Figure 1 (arrow R).

[0023] In this specification, the center of the rolling bearing in the width direction will be approximately (e.g., Figure 1 The width direction of the symbol C is called the "inner width direction" (e.g., refer to...). Figure 1 Arrow BI), referring to the width direction away from the center of the width direction as "outer width direction" (e.g., see arrow BI). Figure 1 Arrow BO), referring to the radial direction closest to the axis of rotation as the "radial inner side" (e.g., see reference BO). Figure 1 The arrow RI) refers to the radial direction away from the said rotation center axis as the "radial outer" (e.g., refer to...). Figure 1 (arrow RO).

[0024] [Rolling bearings] Figure 1 The rolling bearing 10 shown includes an outer ring 11, an inner ring 12, rolling elements 13, a cage 14, and a bearing seal 1. The rolling elements 13 roll between the raceway surfaces of the outer ring 11 and the inner ring 12. The cage 14 guides the rolling elements 13 at predetermined intervals and holds them in a rotatable position. The outer periphery of the bearing seal 1 engages with the engagement groove 11A of the outer ring 11, and the inner periphery of the bearing seal 1 contacts the inner surface of the sealing groove 12A of the inner ring 12.

[0025] [Bearing Seals] Figure 1 and Figure 2 The bearing seal 1 shown includes an annular sealing ring 2. The sealing ring 2 has an annular core 3 and an annular elastomer 4 made of rubber material. The core 3 is used to improve the strength of the bearing seal 1. Conductive fibers 5 are integrally formed on the surface portion of the elastomer 4 on one side (inner side BI) of the thickness direction (width direction B). The conductive fibers 5 are carbon fibers or chemical fibers coated with metals such as copper, nickel, or silver.

[0026] like Figure 3 and Figure 4 As shown in the schematic diagram, the conductive fiber 5 integrated with the surface layer D on one surface 4A side of the elastomer 4 is in a cloth-like form, consisting of a portion 6 protruding from the surface 4A of the elastomer 4 and a portion 7 embedded inside the elastomer 4. Therefore, the portion 6, which is part of the conductive fiber 5, is exposed from the surface 4A. Thus, in the surface layer D on one surface 4A side of the elastomer 4, the conductive fiber 5 is integrated, and a portion of the conductive fiber 5 is exposed, thereby forming a conductive texture A with conductivity. The conductive fiber 5 integrated with the surface layer D on one surface 4A side of the elastomer 4 can also be... Figure 5The non-woven fabric shown can have a planar structure for the conductive fibers 5. Furthermore, the actual shape of the conductive texture A in the bearing seal 1 is annular.

[0027] The bearing seal 1 with such conductive texture A can be easily manufactured, for example, by direct compression molding as follows.

[0028] That is, firstly, a ring-shaped core 3 is set on the lower mold, and a ring-shaped pre-vulcanized rubber, which serves as an elastomer 4, is set on it. Then, a ring-shaped sheet of conductive fibers 5, resembling cloth or non-woven fabric, is set on it. Next, the upper mold is closed and heated, and pressure is applied while the pre-vulcanized rubber is vulcanized to form the product. As a result, the rubber flows into the gaps between the conductive fibers 5 while forming the product. After the rubber has vulcanized, the molded product is removed from the mold, resulting in a product with… Figure 2 The bearing seal 1 with conductive texture A shown.

[0029] like Figure 1 and Figure 2 As shown, in the bearing seal 1, the conductive fibers 5 exposed from the surface of the outer peripheral portion 8 of the elastomer 4 contact the outer ring 11, and the conductive fibers 5 exposed from the surface of the inner peripheral portion 9 of the elastomer 4 contact the inner ring 12. Thus, the outer ring 11 and the inner ring 12 are electrically connected. Figure 1 and Figure 2 In the example shown, the conductive fiber 5 that contacts the inner ring 12 is in contact with the inner ring 12 in the width direction B.

[0030] [Variation Example] Depending on the required strength of bearing seal 1, the parts used to increase the strength of bearing seal 1 can also be removed. Figure 2 Core 3. Figure 6 This represents an example of a bearing seal 1 without a core 3.

[0031] have Figure 6 The bearing seal 1 with the conductive texture A shown can be easily manufactured, for example, by direct compression molding as follows.

[0032] That is, firstly, a ring-shaped pre-curing rubber, which serves as an elastomer 4, is placed on the lower mold, and a ring-shaped sheet of conductive fibers 5, resembling cloth or non-woven fabric, is then placed on it. Next, the upper mold is closed and heated, and pressure is applied while the pre-curing rubber is vulcanizing to form the product. As a result, the rubber flows into the gaps between the conductive fibers 5 while forming the product. After the rubber has vulcanized, the molded product is removed from the mold, resulting in a product with… Figure 6 The bearing seal 1 with conductive texture A shown.

[0033] It can also be different. Figure 2 and Figure 6The structure shown is such that the conductive fiber 5 in contact with the inner ring 12 contacts the inner ring 12 in the width direction B, but rather as... Figure 7 The conductive fiber 5, which is in contact with the inner ring 12, is made to contact the outer peripheral surface 12B of the inner ring 12 in a radial direction, as shown.

[0034] Figure 8 The variation shown illustrates the following example: with the engaging portion 3A of the core 3 engaged in the engaging groove 11A of the outer ring 11 without the conductive fiber 5 contacting the outer ring 11, the core 3 is made to be conductive to the outer ring 11 by contacting the outer ring 11.

[0035] That is, in Figure 8 In this example, the sealing ring 2 is composed of a core 3 having an engaging portion 3A that engages with the outer ring 11, and an elastomer 4 that engages with the core 3. Conductive fibers 5 are integrated with a surface portion of one surface of the elastomer 4, with a portion of the conductive fibers 5 exposed from this surface, forming a conductive texture A on the surface side of the elastomer 4. Furthermore, the conductive fibers 5 exposed from the surface of the outer peripheral portion 8 of the elastomer 4 contact the core 3, and the conductive fibers 5 exposed from the surface of the inner peripheral portion 9 of the elastomer 4 contact the inner ring 12.

[0036] have Figure 8 The bearing seal 1 with the conductive texture A shown can be easily manufactured, for example, by direct compression molding as follows.

[0037] That is, firstly, a ring-shaped core 3 is set on the lower mold, and a ring-shaped sheet of conductive fibers 5 in the form of cloth or non-woven fabric is set on it, and a ring-shaped pre-vulcanized rubber, which serves as an elastomer 4, is set on it. Next, the upper mold is closed and heated, and pressure is applied while the pre-vulcanized rubber is vulcanized to form the product. Thus, the rubber flows into the gaps between the conductive fibers 5 while forming the product. After the rubber has vulcanized, the molded product is removed from the mold, resulting in a product with… Figure 8 The bearing seal 1 with conductive texture A shown.

[0038] [Effects] According to the structure of the bearing seal 1 of the embodiment of the present invention as described above, in Figure 2 , Figure 6 and Figure 7 In the example, the conductive fiber 5 exposed on one side of the outer periphery 8 of the elastomer 4 contacts the outer ring 11. Figure 8 In this example, the conductive fiber 5 exposed on one side of the outer peripheral portion 8 of the elastomer 4 contacts the core 3, and the core 3 contacts the outer ring 11. Therefore, the conduction between the conductive fiber 5 and the outer ring 11 becomes reliable.

[0039] exist Figure 2, Figure 6 , Figure 7 and Figure 8 In the bearing seal 1, the conductive texture A is circular in shape, and the conductive fiber 5 on the inner diameter side of the conductive texture A slides in contact with the inner ring 12. Therefore, the conductivity can be stably ensured no matter which position of the conductive texture A in the circumferential direction contacts the inner ring 12.

[0040] Therefore, through the bearing seal 1 with conductive texture A, the conduction between the outer ring 11 and the inner ring 12 becomes stable and reliable. Thus, when a potential difference is generated between the outer ring 11 and the inner ring 12, current flows through conductive texture A, thereby preventing the rolling bearing 10 from becoming charged and generating sparks. As a result, the resistance to electrolytic corrosion of the rolling bearing 10 is improved.

[0041] exist Figure 2 , Figure 6 , Figure 7 and Figure 8 In the bearing seal 1, conductive fibers 5 are integrally formed on the surface layer of one side of the elastomer 4, so the possibility of the conductive fibers 5 being peeled off from the elastomer 4 is very small.

[0042] exist Figure 2 , Figure 6 , Figure 7 and Figure 8 In the bearing seal 1, the conductive fiber 5 exposed from one surface of the elastomer 4 slides in contact with the inner ring 12, thus reducing the resistance to current transmission and preventing the formation of an oil film on the sliding surface of the conductive elastomer and the inner ring in the presence of lubricant, thereby ensuring stable contact for current transmission.

[0043] exist Figure 2 , Figure 6 , Figure 7 and Figure 8 In the bearing seal 1, the conductive fiber 5 is integrated with the surface layer of one of the surfaces of the elastomer 4 of the bearing seal 1, so that a portion of the conductive fiber 5 is exposed from the surface. Since the conductive fiber 5 exists only in the surface layer of the elastomer 4, where the position is relatively easy to control, there is no manufacturing difficulty, and the manufacturing of the bearing seal 1 becomes easy.

[0044] exist Figure 2 , Figure 6 , Figure 7 and Figure 8 In the bearing seal 1, instead of the elastomer 4 sliding on the inner ring 12, it is the conductive fiber 5 exposed from the surface of the elastomer 4. Therefore, compared with the structure that makes the conductive elastomer slide on the inner ring, conductivity can be obtained with low torque.

[0045] The above embodiments are all illustrative and are not intended to limit the scope thereof. Various modifications and alterations can be made without departing from the scope of the invention.

[0046] Label Explanation 1. Bearing seals 2. Sealing ring 3 core bones 3A Card Connector 4. Elastomers 4A surface 5. Conductive fibers 6. The portion protruding from the surface of the elastomer 7. The portion embedded inside the elastomer 8 Peripheral part 9. Inner Peripheral Region 10 Rolling bearings 11 Outer ring 11A engagement slot 12 Inner Circle 12A Sealing Groove 12B outer periphery 13 Rolling elements 14 Retainer A conductive texture B width direction Inner side of BI width direction BO (outer side of width) C-width direction center D surface layer R radial RI radial inner side RO Radial outer side

Claims

1. A bearing seal for use in a rolling bearing comprising an outer ring, an inner ring, and rolling elements, and comprising an annular sealing ring, wherein, The sealing ring has an elastomer made of rubber material. Conductive fibers are integrally formed on the surface layer of one side of the elastomer, and a portion of the conductive fibers are exposed from the surface. The conductive fibers exposed on the surface of the outer periphery of the elastomer come into contact with the outer ring. The conductive fibers exposed from the surface of the inner periphery of the elastomer come into contact with the inner ring.

2. A bearing seal for use in a rolling bearing comprising an outer ring, an inner ring, and rolling elements, and comprising an annular sealing ring, wherein, The sealing ring includes a core having an engaging portion that engages with the outer ring and an elastic body that engages with the core. Conductive fibers are integrally formed on the surface layer of one side of the elastomer, and a portion of the conductive fibers are exposed from the surface. The conductive fibers exposed from the outer periphery of the elastomer come into contact with the core. The conductive fibers exposed from the surface of the inner periphery of the elastomer come into contact with the inner ring.

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