Rolling bearing for preventing electric corrosion

Abstract

To provide a bearing which can maintain an excellent electric corrosion suppression effect for a long period of time compared to the case where an insulation film is formed on an outer ring or an inner ring.SOLUTION: A rolling bearing for preventing an electric corrosion according to the invention includes: an outer ring 101; an inner ring 102; a rolling element 103; and an insulation cover 111 covering an outer side of the outer ring 101 and an insulation cover 121 covering an inner side of the inner ring 102. An alumite coating is formed on surfaces of the insulation covers 111, 121, and includes: cylindrical parts 111a, 121a along an outer peripheral surface 101a of the outer ring 101 and an inner peripheral surface 102a of the inner ring 102; annular parts 111b, 121b curved along one end faces 101b, 102b of the outer ring 101 and the inner ring 102 respectively by a press molding on one end of the cylindrical parts 111a, 121a; and caulking parts 111c, 121c curved by caulking along the other end faces 101c, 102c of the outer ring 101 and the inner ring 102 from the other end of the cylindrical parts 111a, 121a.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a rolling bearing having effective electrolytic corrosion prevention measures. [Background technology]

[0002] In recent years, with the progress of development of electric cars (EVs) and hybrid cars (HVs), the number of high-voltage parts installed in one automobile is increasing. When current from these high-voltage parts is passed through a bearing, electrolytic corrosion occurs on the surfaces of the rolling elements of the bearing and on the raceway surfaces of the outer and inner rings, which is one of the causes of damage. For example, Patent Document 1 discloses an aluminum bearing in which the outer and inner rings are formed from an aluminum alloy and the entire surface or the driving surface of each is anodized. Patent Document 2 discloses an insulated bearing device in which an insulating coating (made of baked ceramic or resin) is provided on the surface of the outer ring to electrically insulate the housing from the outer ring. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-214939 A [Patent Document 2] Patent Publication No. 2022-72101 Summary of the Invention [Problem to be solved by the invention]

[0004] However, forming the outer ring and inner ring from an aluminum alloy as in Patent Document 1 reduces the load capacity of the bearing. When forming the outer ring or inner ring from steel and forming an insulating film on the surface of the outer ring as in Patent Document 2, a paste-like material must be sprayed onto the outer peripheral surface of the outer ring, etc., and then fired, which complicates the processing process and makes it difficult to control the film thickness, making it difficult to improve productivity.

[0005] In view of these problems, the present invention aims to provide an electrolytic corrosion-resistant rolling bearing that is more productive and can maintain good electrolytic corrosion inhibition effects over a long period of time compared to a case in which an insulating film is formed on the outer ring or the inner ring. [Means for solving the problem]

[0006] In order to solve the above problems, a typical configuration of an electrolytic corrosion-resistant rolling bearing according to the present invention comprises an outer ring, an inner ring, rolling elements that roll between the outer ring and the inner ring, and an insulating cover covering the outside of the outer ring or the inside of the inner ring, the insulating cover having an anodized coating formed on its surface and being characterized in having a cylindrical portion that follows the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring, an annular portion bent from one end of the cylindrical portion along one end face of the outer ring or the inner ring by press molding, and a crimped portion bent from the other end of the cylindrical portion by crimping along the other end face of the outer ring or the inner ring.

[0007] Another configuration of the electrolytic corrosion-resistant rolling bearing of the present invention comprises an outer ring, an inner ring, rolling elements that roll between the outer ring and the inner ring, and an insulating cover that covers the outside of the outer ring or the inside of the inner ring, wherein a circumferential groove is formed at an axial midpoint on the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring, and the insulating cover has an anodized coating formed on its surface, and is characterized in having a pair of cylindrical portions divided at the position of the circumferential groove, a pair of annular portions bent from the outer ends of each of the pair of cylindrical portions along the end face of the outer ring or the inner ring by press molding, and a pair of crimped portions formed by bending the inner ends of each of the pair of cylindrical portions into the circumferential groove by crimping. Effect of the Invention

[0008] According to the present invention, it is possible to provide an electrolytic corrosion-resistant rolling bearing which is more productive and can ensure a good electrolytic corrosion suppression effect compared to a case in which an insulating film is formed on the outer ring or the inner ring. [Brief description of the drawings]

[0009] [Figure 1]1 is a diagram illustrating a first embodiment of an electrolytic corrosion-preventive rolling bearing according to the present invention. FIG. [Diagram 2] 10A to 10C are diagrams illustrating a process in which an insulating cover is attached to an outer ring. [Diagram 3] 10A to 10C are diagrams illustrating a process in which an insulating cover is attached to an inner ring. [Figure 4] FIG. 4 is a diagram illustrating a second embodiment of the electrolytic corrosion-preventive rolling bearing of the present invention. [Diagram 5] 10A to 10C are diagrams illustrating a process in which an insulating cover is attached to an outer ring. [Figure 6] 10A to 10C are diagrams illustrating a process in which an insulating cover is attached to an inner ring. [Figure 7] FIG. 11 is a diagram illustrating an electrolytic corrosion prevention rolling bearing according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, shapes, materials, and other specific values ​​shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are given the same reference numerals to avoid repeated explanations, and elements not directly related to the present invention are not shown or explained.

[0011] (First embodiment) Fig. 1 is a diagram illustrating a first embodiment of an electrolytic corrosion-preventive rolling bearing of the present invention (hereinafter simply referred to as "bearing 100"). Fig. 2 is a diagram illustrating a process in which an insulating cover 111 is attached to an outer ring 101. Fig. 3 is a diagram illustrating a process in which an insulating cover 121 is attached to an inner ring 102.

[0012] As shown in Fig. 1, in this embodiment, a bearing 100 includes an outer ring 101, an inner ring 102, a rolling element 103, an insulating cover 111, and an insulating cover 121. Although both insulating covers 111 and 121 are illustrated in Fig. 1, only one of them may be provided.

[0013] The rolling elements 103 roll between the outer ring 101 and the inner ring 102. Although balls are shown as an example of the rolling elements 103, the present invention is not limited to this and it is also possible to apply the present invention to rollers (not shown) as the rolling elements.

[0014] First, the insulating cover 111 will be described. The insulating cover 111 is a cover that covers the outside of the outer ring 101. The insulating cover 111 is mainly composed of aluminum (aluminum or aluminum alloy), and an alumite coating is formed on the surface. The insulating cover 111 has high insulation properties due to the properties of the alumite coating. The alumite coating is formed on the entire front surface, back surface (surface facing the outer ring 101), and end faces of the insulating cover 111.

[0015] The insulating cover 111 has a cylindrical portion 111a, an annular portion 111b, and a crimped portion 111c. Before the anodized aluminum film is formed, aluminum has the advantage of being soft and easy to press mold. After the anodized aluminum film is formed, the anodized aluminum film has the advantage of being hard in addition to being insulating as described above. For example, a thickness of about 0.05 mm can be obtained with hard anodized aluminum, and a hardness of about HV400 (about half that of bearing steel) can be obtained. Therefore, a film with little wear can be formed. This is the same for the insulating cover 121 described later and the insulating cover of the second embodiment described later. When the anodized aluminum film is set to about 0.05 mm thick, it is also possible to perform grinding finishing while leaving the required thickness.

[0016] The cylindrical portion 111a is disposed along the outer peripheral surface 101a of the outer ring 101. The cylindrical portion 111a covers the entire outer peripheral surface 101a of the outer ring 101.

[0017] The annular portion 111b is a portion that is bent from one end of the cylindrical portion 111a by press molding (for example, drawing or bulging) along one end face 101b of the outer ring 101. The annular portion 111b covers the entire surface of the end face 101b.

[0018] The crimping portion 111c is a portion that is crimped by bending from the other end of the cylindrical portion 111a along the other end face 101c of the outer ring 101. After being crimped, the crimping portion 111c has a shape that forms a pair with the annular portion 111b, and covers the entire surface of the other end face 101c of the outer ring 101. By crimping the crimping portion 111c to the outer ring 101, the insulating cover 111 and the outer ring 101 are integrated.

[0019] The process of attaching the insulating cover 111 to the outer ring 101 will be described. As shown in FIG. 2(a), the insulating cover 111 is first placed over the outer ring 101 and inserted until the end face 101b of the outer ring 101 abuts against the annular portion 111b of the insulating cover 111. Then, as shown in FIG. 2(b), the tip of the cylindrical portion 111a of the insulating cover 111 protrudes from the outer peripheral surface 101a. This protruding portion is crimped by a roller 500. Then, as shown in FIG. 2(c), the crimped portion 111c of the insulating cover 111 covers the other end face 101c of the outer ring 101. In this way, the insulating cover 111 is fixed to the outer ring 101, and covers and insulates the outer peripheral surface 101a and the end faces 101b and 101c.

[0020] Next, the insulating cover 121 will be described. The insulating cover 121 is a cover that covers the inside of the inner ring 102. The insulating cover 121 is mainly composed of aluminum (aluminum or aluminum alloy), and an alumite coating is formed on the surface. The insulating cover 121 has high insulation properties due to the properties of the alumite coating. The alumite coating is formed on the front surface (the surface not hidden by the inner ring 102), the back surface (the surface on the inner ring 102 side), and the entire end surface of the insulating cover 121. The insulating cover 121 has a cylindrical portion 121a, an annular portion 121b, and a crimped portion 121c.

[0021] The cylindrical portion 121a is disposed along the inner circumferential surface 102a of the inner ring 102. The cylindrical portion 121a covers the entire inner circumferential surface 102a of the inner ring 102.

[0022] The annular portion 121b is a portion bent from one end of the cylindrical portion 121a by press molding (for example, drawing or bulging) along one end face 102b of the inner ring 102. The annular portion 121b covers the entire surface of the end face 102b.

[0023] The crimped portion 121c is a portion that is crimped by bending from the other end of the cylindrical portion 121a along the other end face 102c of the inner ring 102. After being crimped, the crimped portion 121c has a shape that forms a pair with the annular portion 121b, and covers the entire surface of the other end face 102c of the inner ring 102. By crimping the crimped portion 121c to the inner ring 102, the insulating cover 121 and the inner ring 102 are integrated.

[0024] The process of attaching the insulating cover 121 to the inner ring 102 will be described. As shown in FIG. 3(a), the insulating cover 121 is first placed over the inner ring 102 and inserted until the end face 102b of the inner ring 102 abuts against the annular portion 121b of the insulating cover 121. Then, as shown in FIG. 3(b), the tip of the cylindrical portion 121a of the insulating cover 121 protrudes from the inner circumferential surface 102a. This protruding portion is crimped by a roller 500. Then, as shown in FIG. 3(c), the crimped portion 121c of the insulating cover 121 covers the other end face 102c of the inner ring 102. In this way, the insulating cover 121 is fixed to the inner ring 102, and covers and insulates the inner circumferential surface 102a and the end faces 102b and 102c.

[0025] According to the configuration of the bearing 100 described above, since the anodized aluminum coating is an insulator, it is possible to prevent electrolytic corrosion of the outer ring 101, the inner ring 102, and the rolling elements 103. Here, since the insulating cover 111 is crimped to the outer ring 101 and the insulating cover 121 is crimped to the inner ring 102, the insulating cover 111 does not slide against the outer ring 101, and the insulating cover 121 does not slide against the inner ring 102. For example, even if the bearing 100 is subjected to an axial force, the insulating covers 111 and 121 do not slide in the axial direction against the outer ring 101 and the inner ring 102. Furthermore, even if creep occurs in the bearing 100, since they are integrated by crimping, they do not slide in the circumferential direction either. Therefore, it is possible to provide a bearing 100 in which the anodized aluminum coating is less likely to wear, productivity is high, and good electrolytic corrosion suppression effects can be maintained for a long period of time.

[0026] Furthermore, insulating functions can be obtained by simply attaching insulating covers 111, 121 to existing bearings. Compared to existing Ceraball bearings, costs can be reduced because there is no need to use Ceraballs and it is sufficient to attach insulating covers 111, 121. Compared to bearings made by injection molding insulating resin, the initial mold costs can be reduced, and operation costs can also be reduced because press molding, anodizing, crimping, etc. are used.

[0027] Furthermore, each of insulating covers 111, 121 is anodized on two surfaces, the front surface and the back surface, so there is one more insulating film than when an insulating film is formed on outer ring 101 or inner ring 102. Even if the anodized film on the housing side of insulating cover 111 or the shaft side (i.e., the outside) of insulating cover 121 wears away, the anodized film on the outer ring side of insulating cover 111 or the inner ring side (i.e., the inside) of insulating cover 121 does not wear away. This improves insulation.

[0028] In addition, because the housing of the motor and reducer of an EV is also made of aluminum, the insulating cover 111 fixed to the outer ring 101 is made of the same material as the housing, and has good compatibility. This is because the difference in linear expansion coefficient between the insulating cover 111 and the housing is small if they are made of the same material. In addition, the risk of gaps or relative misalignment between the insulating cover 111 and the housing is reduced, so stable performance can be expected.

[0029] Second embodiment 4 is a diagram illustrating a second embodiment of an electrolytic corrosion-resistant rolling bearing according to the present invention (hereinafter, simply referred to as "bearing 200"). Note that in the following embodiment, the same components as those in the previously described embodiment are given the same reference numerals and description thereof will be omitted.

[0030] In the bearing 100 of the first embodiment, the insulating cover is configured with one insulating cover 111 fixed to the outer ring 101 and one insulating cover 121 fixed to the inner ring 102. In contrast, in the bearing 200 of the second embodiment, the insulating cover is configured with two insulating covers, a pair of insulating covers 211 and 212 fixed to the outer ring 101, and two insulating covers, a pair of insulating covers 221 and 222 fixed to the inner ring 102. In addition, a groove 101d is formed in the outer peripheral surface 101a of the outer ring 101, and a groove 102d is formed in the inner peripheral surface 102a of the inner ring 102. Note that, although both the pair of insulating covers 211 and 212 and the pair of insulating covers 221 and 222 are depicted in FIG. 4, only one of them may be provided. This will be described in detail below.

[0031] First, the outer ring 101 side will be described. A circumferential groove 101d is formed at an axial midpoint on the outer peripheral surface 101a of the outer ring 101. In this embodiment, the axial midpoint is the middle position of the outer peripheral surface 101a in the axial direction, but it may be provided at a position offset to either end.

[0032] The pair of insulating covers 211, 212 are covers that cover the outside of the outer ring 101. The pair of insulating covers 211, 212 are mainly made of aluminum (aluminum or aluminum alloy), and an alumite coating is formed on the surface. The pair of insulating covers 211, 212 have high insulation properties due to the properties of the alumite coating. The alumite coating is formed on the entire surface of the front side, the back side (the surface on the outer ring 101 side), and the end surface of each of the pair of insulating covers 211, 212. The pair of insulating covers 211, 212 have a pair of cylindrical parts 211a, 212a, a pair of annular parts 211b, 212b, and a pair of crimped parts 211c, 212c. The cylindrical part 211a, the annular part 211b, and the crimped part 211c form one cover. The cylindrical portion 212a, the annular portion 212b, and the crimping portion 212c form a single cover.

[0033] The pair of cylindrical portions 211a, 212a are two cylindrical portions separated at the position of the circumferential groove 101d while being fixed to the outer ring 101. The pair of cylindrical portions 211a, 212a are disposed along the outer peripheral surface 101a of the outer ring 101. The pair of cylindrical portions 211a, 212a cover the entire outer peripheral surface 101a of the outer ring 101.

[0034] The annular portions 211b, 212b are portions bent by press molding (for example, drawing or bulging) from the outer ends of the pair of cylindrical portions 211a, 212a so as to fit the end faces 101b, 101c of the outer ring 101. The annular portions 211b, 212b cover the entire surfaces of the end faces 101b, 101c of the outer ring 101.

[0035] The crimping portions 211c and 212c are formed by crimping the inner ends of the cylindrical portions 211a and 212a by bending them into the circumferential groove 101d. The pair of insulating covers 211 and 212 are integrated with the outer ring 101 by crimping the crimping portions 211c and 212c into the groove 101d.

[0036] Next, the process of attaching the pair of insulating covers 211, 212 to the outer ring 101 will be described. As shown in FIG. 5(a), the pair of insulating covers 211, 212 are placed over the outer ring 101 so as to sandwich the outer ring 101, and are inserted until the end faces 101b, 101c of the outer ring 101 abut against the annular parts 211b, 212b. Then, as shown in FIG. 5(b), the tips of the cylindrical parts 211a, 212a of the pair of insulating covers 211, 212 protrude from the outer peripheral surface 101a and are passed onto the groove 101d. The protruding parts are crimped by the roller 500. Then, as shown in FIG. 5(c), the crimped parts 211c, 212c enter the groove 101d of the outer ring 101. In this way, the pair of insulating covers 211, 212 are fixed to the outer ring 101, covering and insulating the outer circumferential surface 101a and the end faces 101b, 101c.

[0037] Next, the inner ring 102 side will be described. A circumferential groove 102d is formed at an axial midpoint on the inner peripheral surface 102a of the inner ring 102. In this embodiment, the axial midpoint is the middle position of the inner peripheral surface 102a in the axial direction, but it may be provided at a position biased toward either end.

[0038] The pair of insulating covers 221, 222 are covers that cover the inside of the inner ring 102. The pair of insulating covers 221, 222 are mainly made of aluminum (aluminum or aluminum alloy), and an alumite coating is formed on the surface. The pair of insulating covers 221, 222 have high insulation properties due to the properties of the alumite coating. The alumite coating is formed on the entire surface of the front side (the surface not hidden by the inner ring 102), the back side (the surface on the inner ring 102 side), and the end surface of each of the pair of insulating covers 221, 222. The pair of insulating covers 221, 222 have a pair of cylindrical parts 221a, 222a, a pair of annular parts 221b, 222b, and a pair of crimped parts 221c, 222c. The cylindrical part 221a, the annular part 221b, and the crimped part 221c form one cover. The cylindrical portion 222a, the annular portion 222b, and the crimping portion 222c form a single cover.

[0039] The pair of cylindrical portions 221a, 222a are two cylindrical portions separated at the position of the circumferential groove 102d while being fixed to the inner ring 102. The pair of cylindrical portions 221a, 222a are disposed along the inner circumferential surface 102a of the inner ring 102. The pair of cylindrical portions 221a, 222a cover the entire surface of the inner circumferential surface 102a of the inner ring 102.

[0040] The annular portions 221b, 222b are portions bent by press molding (for example, drawing or bulging) from the outer ends of the pair of cylindrical portions 221a, 222a so as to fit along the end faces 102b, 102c of the inner ring 102. The annular portions 221b, 222b cover the entire surfaces of the end faces 102b, 102c of the inner ring 102.

[0041] The crimped portions 221c and 222c are formed by crimping the inner ends of the cylindrical portions 221a and 222a by bending them into the circumferential groove 102d. The pair of insulating covers 221 and 222 are integrated with the inner ring 102 by crimping the crimped portions 221c and 222c into the groove 101d.

[0042] Next, the process of attaching the pair of insulating covers 221, 222 to the inner ring 102 will be described. As shown in FIG. 6(a), the pair of insulating covers 221, 222 are placed over the inner ring 102 so as to sandwich the inner ring 102, and are inserted until the end faces 102b, 102c of the inner ring 102 abut against the annular portions 221b, 222b. Then, as shown in FIG. 6(b), the tips of the cylindrical portions 221a, 222a of the pair of insulating covers 221, 222 protrude from the inner circumferential surface 102a and are passed over the groove 102d. The protruding portions are crimped by the roller 500. Then, as shown in FIG. 6(c), the crimped portions 221c, 222c enter the groove 102d of the inner ring 102. In this manner, the pair of insulating covers 221, 222 are fixed to the inner ring 102, covering and insulating the inner peripheral surface 102a and the end faces 102b, 102c.

[0043] According to the configuration of the bearing 200 described above, since the anodized aluminum coating is an insulator, it is possible to prevent electrolytic corrosion of the outer ring 101, the inner ring 102, and the rolling elements 103. Here, since the insulating covers 211 and 212 are crimped into the groove 101d of the outer ring 101 and the insulating covers 221 and 222 are crimped into the groove 102d of the inner ring 102, the insulating covers 211 and 212 do not slide in the axial direction or the circumferential direction relative to the outer ring 101. Furthermore, the insulating covers 221 and 222 do not slide in the axial direction or the circumferential direction relative to the inner ring 102. As a result, it is possible to provide a bearing 200 that is highly productive and can maintain a good electrolytic corrosion suppression effect for a long period of time, similar to the first embodiment.

[0044] In addition, annular portions 211b, 212b, 221b, and 222b are arranged on both sides of the bearing 200. When the cylindrical portions 211a, 212a, 221a, and 222a are deformed into annular portions by crimping, it is difficult to bend them significantly (because wrinkles will form), but deep drawing, in which the cylindrical portions 211a, 212a, 221a, and 222a and the annular portions 211b, 212b, 221b, and 222b are formed from flat plates by press molding, has fewer limitations (it is possible to suppress wrinkles by pressing). Therefore, the inner diameter of the annular portions 211b, 212b, 221b, and 222b can be made small, and the end faces of the outer ring 101 or the inner ring 102 can be sufficiently covered, and it is also possible to cover the gap between the outer ring 101 and the inner ring 102 to form a seal.

[0045] Third embodiment Fig. 7 is a diagram for explaining a bearing 300 (electrolytic corrosion-resistant rolling bearing) according to a third embodiment. Fig. 7(a) is a cross-sectional view of the bearing 300, and Fig. 7(b) is a front view showing only the outer ring 301. Note that in the following embodiments, the same components as those in the previously described embodiments are given the same reference numerals and description thereof will be omitted.

[0046] As shown in FIG. 7, chamfers 114 are formed at the outer corners of the outer ring 301. The radial width of the chamfers 114 is non-uniform in the circumferential direction. Specifically, in the present embodiment, machining is performed by eccentrically disposing the rotation center of a tool for chamfering the corners of the outer ring 301 with respect to the center of the outer ring 301. Then, since the cutting amount changes in the circumferential direction, the width of the chamfer 114 (the radial width between the outer circumferential circle 114a and the inner circumferential circle 114b) changes from width W1 to width W2 (W1 < W2), becoming non-uniform in the circumferential direction.

[0047] In addition, as a configuration in which the radial width of the chamfer is made non-uniform in the circumferential direction, not only eccentric chamfering but also recesses or notches may be formed by cutting or pressing in a part of the chamfer.

[0048] By caulking the insulating cover 111 to the chamfer 114 that is non-uniform in the circumferential direction in this way, rotation of the insulating cover 111 with respect to the outer ring 301 can be suitably prevented. As a result, even if the outer ring 122 rotates due to creep, the insulating cover 111 will rotate together with the outer ring 301, and the insulating cover 111 and the outer ring 301 will not rotate relative to each other. That is, when the bearing 300 rotates due to creep, only the outer peripheral surface of the insulating cover 111 wears, and the alumite film on the inner peripheral surface does not wear. Therefore, it is possible to maintain good insulation performance over a long period of time.

[0049] As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. Needless to say, the present invention is not limited to such examples. It is obvious that those skilled in the art can conceive of various modification examples or correction examples within the scope described in the claims, and it is naturally understood that those also belong to the technical scope of the present invention.

[0050] In the above embodiment, the anodized aluminum film is formed on the entire outer surface, inner surface, and end face of the insulating covers 111, 121, 211, 212, 221, and 222, but is not limited thereto. For example, in the configuration of the first embodiment, the anodized aluminum film may be formed only on the surface of the insulating cover 111 facing the outer ring 101. Alternatively, the anodized aluminum film may be formed only on the surface of the insulating cover 121 facing the inner ring 102. Similarly, in the configuration of the second embodiment, the anodized aluminum film may be formed only on the surface of the insulating covers 211 and 212 facing the outer ring 101. Alternatively, the anodized aluminum film may be formed only on the surface of the insulating covers 221 and 222 facing the inner ring 102. This is because insulation is maintained as long as the anodized aluminum film facing the outer ring 101 and the inner ring 102 does not peel off due to sliding. [Industrial Applicability]

[0051] The present invention can be used as an electrolytic corrosion prevention rolling bearing that is effective as a measure to prevent electrolytic corrosion. [Explanation of symbols]

[0052] 100...bearing (electrolytic corrosion prevention rolling bearing), 101...outer ring, 101a...outer peripheral surface, 101b...one end face, 101c...other end face, 101d...groove, 102...inner ring, 102a...inner peripheral surface, 102b...one end face, 102c...other end face, 102d...groove, 103...rolling element, 111...insulating cover, 111a...cylindrical portion, 111b...annular portion, 111c...crimping portion, 121...insulating cover, 121a...cylindrical portion, 121b...annular portion, 12 1c...crimped portion, 200...bearing (electrolytic corrosion prevention rolling bearing), 211...insulating cover, 211a...cylindrical portion, 211b...annular portion, 211c...crimped portion, 212...insulating cover, 212a...cylindrical portion, 212b...annular portion, 212c...crimped portion, 221...insulating cover, 221a...cylindrical portion, 221b...annular portion, 212c...crimped portion, 222...insulating cover, 222a...cylindrical portion, 222b...annular portion, 222c...crimped portion, 500...roller

Claims

1. The bearing comprises an outer ring, an inner ring, rolling elements that roll between the outer ring and the inner ring, and an insulating cover that covers an outside of the outer ring or an inside of the inner ring, The insulating cover has an anodized aluminum coating formed on its surface, a cylindrical portion along an outer peripheral surface of the outer ring or an inner peripheral surface of the inner ring; an annular portion bent from one end of the cylindrical portion along one end surface of the outer ring or the inner ring by press molding; a crimping portion bent by crimping from the other end of the cylindrical portion along the other end surface of the outer ring or the inner ring; An electrolytic corrosion-resistant rolling bearing comprising:

2. The bearing comprises an outer ring, an inner ring, rolling elements that roll between the outer ring and the inner ring, and an insulating cover that covers an outside of the outer ring or an inside of the inner ring, a circumferential groove is formed in an outer peripheral surface of the outer ring or an inner peripheral surface of the inner ring at an axial midpoint; The insulating cover has an anodized aluminum coating formed on its surface, A pair of cylindrical portions divided at the position of the circumferential groove; a pair of annular portions bent from outer ends of the pair of cylindrical portions along end surfaces of the outer ring or the inner ring by press molding; a pair of crimping portions in which inner ends of the pair of cylindrical portions are bent into the circumferential groove by crimping; An electrolytic corrosion-resistant rolling bearing comprising:

Images