Bearing seal

Abstract

Provided is a bearing seal for preventing electrical corrosion of a rolling bearing, the bearing seal being capable of ensuring electrical conductivity, having no technical difficulty in manufacturing, and having no increase in manufacturing cost. The bearing seal is provided with a first metal plate (2A) and a second metal plate (2B) which are annular, and a conductive material (3) sandwiched between the first metal plate (2A) and the second metal plate (2B). One or both of the first metal plate (2A) and the second metal plate (2B) are in contact with the outer ring. The conductive material (3) is an annular felt (4) having conductivity. The annular felt (4) is provided with an extending and protruding part (6) extending and protruding from the inner side end (5) of the first metal plate (2A) and the second metal plate (2B) in the radial direction (R) to the inner side (RI) in the radial direction (R). The inner peripheral surface (4A) of the annular felt (4) is in contact with the inner ring (12).

Description

Technical Field

[0001] The present invention relates to a bearing seal for preventing electrical corrosion of a rolling bearing. Background Art

[0002] For example, in electric vehicle motors and reducer units, as well as inverter-driven motors outside of electric vehicles, current can leak and flow toward the rotating shaft. In these cases, the current can disrupt the lubricating oil film in the rolling bearings supporting the rotating shaft, flowing between the inner and outer rings and causing damage to the rolling surfaces of the rolling elements due to arcing.

[0003] As a bearing seal for preventing electrical corrosion of such rolling bearings, there is a bearing seal consisting of an annular sealing plate fixed to a sealing groove of the outer ring of the rolling bearing, and a conductive annular sliding part mounted on the sealing plate and in sliding contact with the outer periphery of the inner ring of the rolling bearing (for example, see patent document 1).

[0004] The sealing plate is an annular member made of two metal plates, which sandwich and support the sliding member. The sliding member is a plain woven fabric woven with conductive fibers and low-friction fibers, and thus has conductivity.

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-106971

[0006] When a plain-woven sliding member having a structure like that disclosed in Patent Document 1 is used, the sliding member is a combination of conductive fibers and non-conductive fibers, and thus has a surface that does not exhibit conductivity.

[0007] Combining two types of fibers, conductive fibers and low-friction fibers, to form a plain-woven fabric as in Patent Document 1 in order to achieve the desired conductivity and low friction properties is technically difficult, and therefore increases production costs. Summary of the Invention

[0008] An object of the present invention is to provide a bearing seal for preventing electric corrosion of a rolling bearing, which can ensure electrical conductivity without requiring technical difficulty or increasing manufacturing costs.

[0009] To address the aforementioned issues, the bearing seal of the present invention is a bearing seal for a rolling bearing comprising an outer ring, an inner ring, and rolling elements, and comprises: an annular first metal plate and a second metal plate; and a conductive material sandwiched between the first and second metal plates. One or both of the first and second metal plates are in contact with the outer ring, or conductive rubber covering the radially outer portions of the first and second metal plates and extending radially outward is in contact with the outer ring. The conductive material is an annular felt having conductivity. The annular felt has an extended portion extending radially inward from the radially inner ends of the first and second metal plates, and the inner circumferential surface of the annular felt is in contact with the inner ring.

[0010] To address the aforementioned issues, the bearing seal of the present invention is a bearing seal for a rolling bearing comprising an outer ring, an inner ring, and rolling elements, and comprises: an annular first metal plate and a second metal plate; and a conductive material sandwiched between the first and second metal plates. One or both of the first and second metal plates are in contact with the inner ring, or conductive rubber covering the radially inner portions of the first and second metal plates and extending radially inward is in contact with the inner ring. The conductive material is an annular felt having conductivity. The annular felt has an extension extending radially outward from the radially outer ends of the first and second metal plates, and the outer circumferential surface of the annular felt is in contact with the outer ring.

[0011] In the bearing seal structure described above, the conductive material sandwiched between the first and second metal plates is a conductive annular felt, and the inner or outer circumference of the annular felt slides against the inner or outer ring. Therefore, regardless of where the annular felt, a sliding member sliding against the inner or outer ring, comes into contact with the inner or outer ring, it remains conductive, ensuring proper conductivity.

[0012] Furthermore, the conductive material is felt, which is a material formed by winding conductive fibers themselves. Therefore, it does not need to be woven, and there is no technical difficulty in manufacturing and it is easy to manufacture, so the manufacturing cost does not increase.

[0013] Moreover, when the outer surface and the inner surface of the annular felt extension protrusion in the width direction of the rolling bearing are exposed, the above-mentioned extension protrusion also has the performance of a normal felt seal, and has a filtering effect to prevent foreign matter from entering the bearing interior in the oil.

[0014] Here, in a preferred embodiment, rubber sheets extending in the radial direction are additionally provided on the extended protrusion of the annular felt, and the rubber sheets are separated in the circumferential direction and arranged at substantially equal intervals.

[0015] This bearing seal structure utilizes the elasticity of the rubber sheet attached to the extended portion of the conductive annular felt to enhance the reaction force against the sliding surface, thereby ensuring long-term conductivity. Furthermore, the felt is exposed between circumferentially adjacent rubber sheets, maintaining its performance as a felt seal.

[0016] In a preferred embodiment, a rubber film is added to the extended portion of the annular felt so as to cover substantially the entire surface of the extended portion.

[0017] This bearing seal structure utilizes the elasticity of the rubber film, which is applied over substantially the entire surface of the conductive annular felt extension, to uniformly apply a reaction force to the sliding surface, further enhancing the reaction force. This ensures more stable and long-term conductivity.

[0018] In a preferred embodiment, a seal lip is provided on the inner side of the extension of the annular felt in the width direction of the rolling bearing so as to extend away from the extension and contact the inner ring or the outer ring.

[0019] According to this bearing seal structure, the sealing performance of the rolling bearing is improved by providing a sealing lip that contacts the inner ring or the outer ring. Therefore, it is a preferred embodiment when the rolling bearing is a grease-filled type.

[0020] As described above, in the bearing seal of the present invention, the inner or outer circumferential surface of the conductive annular felt slides against the inner or outer ring. Therefore, conductivity remains constant regardless of where the inner or outer circumferential surface of the sliding member sliding against the inner or outer ring contacts the inner or outer ring, ensuring stable and reliable conductivity. Furthermore, since the conductive material is felt, it does not require weaving, resulting in easy manufacturing without technical difficulties, thus minimizing manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a partially cutaway perspective view of a rolling bearing according to an embodiment of the present invention, illustrating an example in which a first metal plate is in contact with an outer ring, and an inner peripheral surface of an annular felt serving as a conductive material is in contact with an inner ring.

[0022] Figure 2 yes Figure 1 An enlarged longitudinal sectional view of the main parts of a rolling bearing.

[0023] Figure 3 When viewed from the direction of the rotation center axis Figure 1 The figure is obtained for the rolling bearing.

[0024] Figure 4 This is an enlarged longitudinal sectional view of the main parts of the rolling bearing involved in an embodiment of the present invention, showing an example of the following situation: the inner ring that the inner peripheral surface of the annular felt serving as the conductive material contacts is not a cylindrical surface serving as the outer peripheral surface in the width direction, but an inclined surface that approaches the radial outer side as it approaches the inner side in the width direction.

[0025] Figure 5 This is a partial cross-sectional stereoscopic view of a rolling bearing involved in an embodiment of the present invention, showing the following example: a conductive rubber covering the radially outer portion of the first metal plate and the second metal plate and extending radially outward is in contact with the outer ring, and the inner circumferential surface of the annular felt serving as the conductive material is in contact with the inner ring.

[0026] Figure 6 yes Figure 5 An enlarged longitudinal sectional view of the main parts of a rolling bearing.

[0027] Figure 7 When viewed from the direction of the rotation center axis Figure 5 The figure is obtained for the rolling bearing.

[0028] Figure 8 is a partial cross-sectional perspective view of a rolling bearing according to an embodiment of the present invention, showing the following example: Figure 5 In the rolling bearing, a rubber sheet extending in the radial direction is added to the extended protrusion of the annular felt as the conductive material.

[0029] Figure 9 yes Figure 8 An enlarged longitudinal sectional view of the main parts of a rolling bearing.

[0030] Figure 10 When viewed from the direction of the rotation center axis Figure 8 The figure is obtained for the rolling bearing.

[0031] Figure 11 is a partial cross-sectional perspective view of a rolling bearing according to an embodiment of the present invention, showing the following example: Figure 5 In the rolling bearing, a rubber film covering substantially the entire surface of an extended protrusion of an annular felt as a conductive material is additionally provided on the extended protrusion.

[0032] Figure 12 yes Figure 11 An enlarged longitudinal sectional view of the main parts of a rolling bearing.

[0033] Figure 13 When viewed from the direction of the rotation center axis Figure 11 The figure is obtained for the rolling bearing.

[0034] Figure 14 is a partial cross-sectional perspective view of a rolling bearing according to an embodiment of the present invention, showing the following example: Figure 5 In the rolling bearing, a sealing lip is provided on the inner side of the extended protrusion of the annular felt as the conductive material in the width direction of the rolling bearing, which extends away from the extended protrusion and contacts the inner ring.

[0035] Figure 15 yes Figure 14 An enlarged longitudinal sectional view of the main parts of a rolling bearing. DETAILED DESCRIPTION

[0036] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0037] In this specification, the rotation center axis of the rolling bearing (for example, Figure 1 and Figure 3 The direction parallel to the direction of the reference numeral O) is referred to as the "width direction" (for example, referring to Figure 1 and Figure 2 The direction perpendicular to the direction of the central axis of rotation is called the “radial direction” (e.g., referring to Figure 2 and Figure 3 The “circumferential direction” is defined relative to the direction of the central axis of rotation (e.g., referring to Figure 1 and Figure 3 arrow C).

[0038] In this specification, the center of the rolling bearing in the width direction (for example, Figure 2 The width direction of the reference numeral D) is referred to as the "inner side in the width direction" (for example, referring to Figure 2 The width direction away from the center of the width direction is referred to as the "outer side of the width direction" (for example, refer to Figure 2 The radial direction close to the above-mentioned rotation center axis is referred to as the "radial inner side" (for example, referring to Figure 2 The radial direction away from the above-mentioned rotation center axis is called the "radial outer side" (for example, refer to Figure 2 Arrow RO).

[0039] [Rolling bearings]

[0040] Figures 1 to 15 The rolling bearing A shown includes an outer ring 11, an inner ring 12, rolling elements 13, a retainer 14, and a bearing seal 1. The rolling elements 13 roll between the raceway surfaces of the outer ring 11 and the raceway surfaces of the inner ring 12. The retainer 14 guides the rolling elements 13 at predetermined intervals and retains them rotatably.

[0041] [Bearing seals]

[0042] Figures 1 to 15 The bearing seal 1 shown includes an annular first metal plate 2A and a second metal plate 2B, and a conductive material 3 sandwiched between the first and second metal plates 2A, 2B. The conductive material 3 is a conductive annular felt 4. The annular felt 4 has an extended portion 6 extending from an inner end 5 in the radial direction R of the first and second metal plates 2A, 2B toward an inner side RI in the radial direction R. The inner circumferential surface 4A of the annular felt 4 contacts the inner ring 12.

[0043] The conductive annular felt 4 is formed by winding conductive fibers. The conductive fibers can be carbon fibers or metal-coated chemical fibers. The metal coating the chemical fibers can be copper, silver, and / or nickel. The carbon fibers can also be reinforced by mixing them with polyester resins or polyvinyl chloride resins.

[0044] exist Figures 1 to 4 In the bearing seal 1 shown, the first metal plate 2A enters the retaining groove 11A of the outer ring 11, and the first metal plate 2A contacts the outer ring 11. It is sufficient to make one or both of the first metal plate 2A and the second metal plate 2B contact the outer ring 11. Figures 5 to 15 In the bearing seal 1 shown, the conductive rubber 7 covering the radially outer side RO of the first metal plate 2A and the second metal plate 2B and extending outward RO in the radial direction R enters the retaining groove 11A of the outer ring 11, and the conductive rubber 7 contacts the outer ring 11.

[0045] The conductive rubber 7 is made of conductive nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), acrylic rubber (ACM), silicone rubber (VQM), fluororubber (FKM), ethylene propylene diene monomer (EPDM), or the like.

[0046] exist Figures 8 to 10 In the bearing seal 1 shown, rubber sheets 8 extending in the radial direction R are additionally provided on the surface of the extended protrusion 6 of the annular felt 4 on the outer side BO in the width direction B of the rolling bearing A. The rubber sheets 8 are separated in the circumferential direction C and arranged at substantially equal intervals.

[0047] according to Figures 8 to 10 The structure of the bearing seal 1 shown in the figure increases the reaction force on the sliding surface by the elasticity of the rubber sheet 8 added to the extended protrusion 6 of the conductive annular felt 4, thereby ensuring conductivity for a long time.

[0048] exist Figures 11 to 13 In the bearing seal 1 shown, a rubber film 9 is provided on the surface of the extended portion 6 of the annular felt 4 on the outer side BO in the width direction B of the rolling bearing A, covering substantially the entire surface.

[0049] according to Figures 11 to 13 The structure of the bearing seal 1 shown above utilizes the elasticity of the rubber film 9, which is added to substantially the entire surface of the extended protrusion 6 of the conductive annular felt 4. This uniformly applies a reaction force to the sliding surface, further enhancing the reaction force. This ensures more stable and long-term conductivity.

[0050] exist Figure 14 and Figure 15 In the bearing seal 1 shown, a seal lip 10 is provided on the inner side BI of the extension 6 of the annular felt 4 in the width direction B of the rolling bearing A, extending away from the extension 6 and contacting the inner ring 12.

[0051] according to Figure 14 and Figure 15 The structure of the bearing seal 1 shown improves the sealing performance of the rolling bearing A by providing the seal lip 10 in contact with the inner ring 12. Therefore, it is preferable as an embodiment when the rolling bearing A is a grease-packed type.

[0052] exist Figures 1 to 15 In the embodiment shown, Figure 2 、 Figure 6 、 Figure 9 、 Figure 12 as well as Figure 15 In the example shown, the inner peripheral surface 4A of the annular felt 4 serving as the conductive material 3 is in contact with the cylindrical surface of the inner ring 12 serving as the outer peripheral surface in the width direction B. The present invention is not limited to such a structure. Figure 4 As shown, the inner peripheral surface 4A of the annular felt 4 serving as the conductive material 3 may be brought into contact with the inclined surface of the inner ring 12 that approaches the radially outer side RO as it approaches the widthwise inner side BI.

[0053] exist Figures 1 to 15 The bearing seal 1 shown is of an inner ring sliding type in which the inner peripheral surface 4A of the annular felt 4 slides on the outer peripheral surface of the inner ring 12. The present invention is not limited to such a structure, and an outer ring sliding type may also be employed.

[0054] In the case of the outer ring sliding type, one or both of the first metal plate 2A and the second metal plate are in contact with the inner ring 12, or the conductive rubber covering the inner side RI of the first metal plate 2A and the second metal plate 2B in the radial direction R and extending inward RI of the radial direction R is in contact with the inner ring 12. Furthermore, the annular felt 4, which is the conductive material 3 sandwiched between the first metal plate 2A and the second metal plate 2B, has an extended portion extending from the outer end of the first metal plate 2A and the second metal plate 2B in the radial direction R toward the outer side RO of the radial direction R, and the outer peripheral surface of the annular felt 4 is in contact with the outer ring 11. In this case, Figure 14 and Figure 15 Such a seal lip extends away from the above-mentioned extended portion and contacts the outer ring 11 .

[0055] [Effects]

[0056] In the structure of the bearing seal 1 according to the embodiment of the present invention, the conductive material 3 sandwiched between the first metal plate 2A and the second metal plate 2B is a conductive annular felt 4, and the inner circumferential surface 4A or the outer circumferential surface of the annular felt 4 slides on the inner ring 12 or the outer ring 11. Therefore, the annular felt 4, which serves as a sliding member sliding on the inner ring 12 or the outer ring 11, remains conductive regardless of where it comes into contact with the inner ring 12 or the outer ring 11, ensuring proper conductivity.

[0057] And the conductive material 3 is felt, is the material that makes conductive fiber itself be wound and formed. Therefore, need not weave, do not have technical difficulty and easily manufacture on the manufacture, so manufacturing cost can not increase.

[0058] Moreover, when the surface BO of the extended protrusion 6 of the annular felt 4 on the outer side in the width direction B of the rolling bearing A and the surface on the inner side BI are exposed, the extended protrusion 6 also has the performance of a normal felt seal and has a filtering effect that prevents foreign matter from entering the interior of the bearing in the oil.

[0059] The above embodiments are described for illustrative purposes only and are not intended to be limiting. Various improvements and modifications can be made without departing from the scope of the present invention.

[0060] Description of Reference Numerals

[0061] 1…bearing seal; 2A…first metal plate; 2B…second metal plate; 3…conductive material; 4…annular felt; 4A…inner circumferential surface; 5…radial inner end; 6…extended protrusion; 7…conductive rubber; 8…rubber sheet; 9…rubber membrane; 10…sealing lip; 11…outer ring; 11A…retaining groove; 12…inner ring; 13…rolling element; 14…retainer; A…rolling bearing; B…width direction; BI…inside; BO…outside; C…circumferential direction; D…center in width direction; R…radial direction; RI…inside; RO…outside.

Claims

1. A bearing seal for a rolling bearing comprising an outer ring, an inner ring, and rolling elements, characterized in that: have: a first annular metal plate and a second annular metal plate; and a conductive material sandwiched between the first metal plate and the second metal plate, One or both of the first metal plate and the second metal plate are in contact with the outer ring, or the conductive rubber covering the radially outer sides of the first metal plate and the second metal plate and extending outward in the radial direction is in contact with the outer ring. The conductive material is a circular felt with conductivity. The annular felt has an extended portion extending radially inward from the radially inner ends of the first metal plate and the second metal plate. The inner peripheral surface of the annular felt is in contact with the inner ring.

2. A bearing seal for a rolling bearing comprising an outer ring, an inner ring, and rolling elements, characterized in that: have: a first annular metal plate and a second annular metal plate; and a conductive material sandwiched between the first metal plate and the second metal plate, One or both of the first metal plate and the second metal plate are in contact with the inner ring, or the conductive rubber covering the radially inner portions of the first metal plate and the second metal plate and extending radially inward is in contact with the inner ring. The conductive material is a circular felt with conductivity. The annular felt has an extended portion extending radially outward from radially outer ends of the first metal plate and the second metal plate. The outer peripheral surface of the annular felt is in contact with the outer ring.

3. The bearing seal according to claim 1 or 2, characterized in that: A rubber sheet extending in the radial direction is added to the extended protrusion of the annular felt. The rubber sheets are separated in the circumferential direction and arranged at substantially equal intervals.

4. The bearing seal according to claim 1 or 2, characterized in that: A rubber film is added to the extended portion of the annular felt to cover substantially the entire surface of the exposed portion.

5. The bearing seal according to claim 1 or 2, characterized in that: A seal lip is provided on the inner side of the extended protrusion of the annular felt in the width direction of the rolling bearing so as to extend away from the exposed portion and contact the inner ring or the outer ring.

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