Insulated bearing

Abstract

To facilitate processing and improve the adhesion of the insulating coating. [Solution] An insulating bearing 1 comprising a plurality of rolling elements 6 between a metal outer ring 2 and an inner ring 3, wherein the outer ring 2 has an anchor recess 10 formed by laser processing on its outer circumferential surface 7a, and a resin insulating coating 9 that covers at least the outer circumferential surface 7a of the outer ring 2 and has a hardened joint portion 9a that fits into the anchor recess 10. The anchor recess 10 is provided at an angle toward the center line 12 in the width direction of the outer ring 2 in a cross section along the bearing axis direction of the outer ring 2 (direction of the central axis 17 of the bearing 1). By providing the anchor recess 10 on the outer circumferential surface 7a of the outer ring 2 and by giving the anchor recess 10 an inclination angle θ1, the adhesion of the resin insulating coating 9 to the outer ring 2 can be improved. Furthermore, since the anchor recess 10 is laser processed, the processing can be performed with high precision.

Description

Technical Field

[0001] The present invention relates to an insulated bearing. More specifically, the present invention relates to a rolling bearing provided with a resin insulating coating on at least one of an outer ring and an inner ring.

Background Art

[0002] In bearings used in motors, generators, vehicle drive devices, etc., electrolytic corrosion may occur where the metal structure dissolves due to current leakage from the fitting surface between the outer peripheral surface of the outer ring and the housing or from the fitting surface between the inner peripheral surface of the inner ring and the shaft. When electrolytic corrosion occurs, damage is caused to the bearing raceway surface, abnormal noise and vibration occur during bearing rotation, the outer and inner rings and rolling elements are damaged, and the life of the bearing is shortened. Therefore, as a bearing, there is an insulated bearing provided with an insulating coating on the fitting surface between the outer peripheral surface of the outer ring and the housing or on the fitting surface between the inner peripheral surface of the inner ring and the shaft in order to prevent electrolytic corrosion caused by the flow of external current (Patent Document 1).

[0003] As the insulating coating of the insulated bearing, resin materials such as phenolic resin, polyimide, polyphenylene sulfide (PPS), etc. are used, but the adhesion between the surface of the outer peripheral surface of the outer ring made of metal and the inner peripheral surface of the inner ring and the insulating coating is poor. Therefore, as a measure for adhesion, an adhesive may be applied between the metal interface of the outer ring and the inner ring and the insulating coating, but it is difficult to apply the adhesive uniformly, and the process of applying it to the inner peripheral surface of the inner ring is not appropriate considering workability and man-hours.

[0004] Therefore, an insulated bearing is known in which the adhesion to the insulating coating is improved by roughening the surface of the outer peripheral surface of the outer ring made of metal (Patent Document 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

[0006] However, in insulated bearings where the outer surface of the outer ring is roughened by blasting to improve adhesion with the insulating coating, while the outer surface can be roughened, the shape and inclination of the uneven parts cannot be controlled, which may lead to unstable adhesion with the outer surface. The present invention aims to provide an insulated bearing that is easy to process and has excellent adhesion of the insulating coating. [Means for solving the problem]

[0007] To achieve the above objective, the present invention provides an insulating bearing comprising a plurality of rolling elements between a metal outer ring and an inner ring, wherein the outer ring has an anchor recess formed by laser processing on its outer circumferential surface, and a resin insulating coating that covers at least the outer circumferential surface of the outer ring and has a hardened bonding portion that fits into the anchor recess, and the anchor recess is provided at an angle toward the centerline in the width direction of the outer ring in a cross section along the bearing axial direction of the outer ring.

[0008] Machining can be used to machine grooves on the outer surface of the metal outer ring and the inner surface of the inner ring, allowing for high-precision groove machining. However, machining carries the risk of distortion and cracking during processing, and the groove opening is larger than the groove width, making it difficult to machine fine grooves. In contrast, this invention employs laser processing. Since laser processing is non-contact with the workpiece, the risk of distortion and cracking during processing is minimized. Furthermore, because only the laser-irradiated area is melted and evaporated, it is easy to control the angle of inclination and depth of the anchor recess, enabling efficient and precise machining of bearings with inclined grooves in a short time.

[0009] Furthermore, the present invention forms inclined anchor recesses on the outer circumferential surface of the metal outer ring, allowing a portion of the resin insulating coating to penetrate the anchor recesses and adhere closely to the side walls within the recesses, thereby increasing the contact area between the outer circumferential surface of the outer ring and the metal. As a result, compared to cases where the outer circumferential surface of the outer ring is roughened by blasting or other processes to ensure adhesion of the insulating coating, the uniform inclination direction of the grooves strengthens the adhesion between the resin insulating coating and the metal, significantly reducing damage and peeling of the resin insulating coating and improving the insulation performance of the insulated bearing.

[0010] Furthermore, since the anchor recess is positioned at an angle toward the centerline in the width direction of the outer ring in a cross-section along the bearing axis direction of the outer ring, the direction of inclination of the anchor recess and the direction of shrinkage of the resin insulating coating during manufacturing almost coincide, thereby enhancing the mechanical anchoring effect and improving the adhesion of the resin insulating coating to the outer surface compared to when the anchor recess is formed perpendicular to the outer surface. This is because the thermal expansion coefficient of the resin insulating coating is greater than that of the metal material of the outer surface of the outer ring. Due to the difference in thermal expansion, the resin material shrinks in the direction of adhesion to the metal after the resin insulating coating is formed, making it easier to penetrate the inclined anchor recess, resulting in a stronger adhesion.

[0011] To ensure the insulating properties of the bearing, it is sufficient to cover at least the outer circumferential surface of the outer ring with a resin insulating coating. However, in order to ensure sufficient contact area with the resin insulating coating, the end faces may also be covered (i.e., both the outer circumferential surface and the end faces).

[0012] Furthermore, the anchor recess is, for example, a groove, and is provided in a continuous ring shape around the entire circumference of the outer surface. However, it is not limited to a continuous ring-shaped groove around the entire circumference; multiple linear grooves formed in the circumferential direction may be arranged on the same line in the circumferential direction. Alternatively, multiple ring-shaped grooves or grooves arranged on the same line in the circumferential direction may be arranged in the width direction of the outer surface. Moreover, it is not limited to grooves; holes or the like may also be used.

[0013] Furthermore, the insulated bearing of the present invention is a bearing comprising a plurality of rolling elements between a metal outer ring and an inner ring, wherein the outer ring has an anchor recess formed by laser processing on its end face, and a resin insulating coating that covers the outer circumferential surface and end face of the outer ring and has a hardened bonding portion that fits into the anchor recess, and the anchor recess is provided at an angle toward the outer circumferential surface in a cross section along the bearing axis direction of the outer ring.

[0014] By forming an inclined anchor recess on the end face of the metal outer ring, a portion of the resin insulating coating enters the anchor recess and adheres closely to the side wall within the recess, thereby increasing the contact area with the metal end face of the outer ring. As a result, compared to cases where the surface of the outer ring end face is roughened by blasting or other processes to ensure adhesion of the insulating coating, the uniform inclination direction of the grooves strengthens the adhesion between the resin insulating coating and the metal, significantly reducing damage and peeling of the resin insulating coating and improving the insulation performance of the insulated bearing.

[0015] Furthermore, since the anchor recess is provided at an angle toward the outer circumferential surface in a cross-section along the bearing axis direction of the outer ring, the direction of inclination of the anchor recess and the direction of shrinkage of the resin insulating coating during manufacturing almost coincide, thereby enhancing the mechanical anchoring effect and improving the adhesion of the resin insulating coating to the end face compared to when the anchor recess is formed perpendicular to the end face. This is because the thermal expansion coefficient of the resin insulating coating is greater than that of the metal material of the end face of the outer ring. Due to the difference in thermal expansion, the resin material shrinks in the direction of adhesion to the metal after the resin insulating coating is formed, making it easier to penetrate the inclined anchor recess, resulting in a stronger adhesion.

[0016] The anchor recess is, for example, a groove, and is provided in a continuous ring shape around the entire circumference of the end face. However, it is not limited to a continuous ring-shaped groove around the entire circumference; multiple linear grooves formed in the circumferential direction may be arranged on the same line in the circumferential direction. Alternatively, multiple ring-shaped grooves or grooves arranged on the same line in the circumferential direction may be arranged in the radial direction of the end face. Furthermore, it is not limited to grooves; holes or the like may also be used.

[0017] Generally, delamination of resin insulating coatings often occurs from the edges. For this reason, in the technology described in, for example, Japanese Patent Application Publication No. 2002-147466, an annular recess is formed on the end face of the outer ring, and delamination is prevented by the insulating coating filling into this recess. However, processing this recess is time-consuming and costly. On the other hand, in the present invention, an anchor recess is formed on the end face of the outer ring by laser processing, so even without the aforementioned recess, the edge of the resin insulating coating can be firmly bonded to the metal, preventing delamination from the edges of the resin insulating coating.

[0018] Furthermore, the insulated bearing of the present invention is a bearing comprising a plurality of rolling elements between a metal outer ring and an inner ring, wherein the outer ring comprises anchor recesses formed by laser processing on the outer circumferential surface and end surface of the outer ring, and a resin insulating coating that covers the outer circumferential surface and end surface of the outer ring and has a hardened bonding portion that fits into the anchor recesses, wherein the anchor recesses formed on the outer circumferential surface are provided at an angle toward the centerline in the width direction of the outer ring in a cross section along the bearing axis direction of the outer ring, and the anchor recesses formed on the end surface are provided at an angle toward the outer circumferential surface in a cross section along the bearing axis direction of the outer ring.

[0019] By forming inclined anchor recesses on the outer circumferential and end faces of the metal outer ring, a portion of the resin insulating coating penetrates the anchor recesses and adheres closely to the side walls within the recesses, thereby increasing the contact area between the outer circumferential surface of the outer ring and the metal end faces. As a result, compared to cases where the outer circumferential and end faces of the outer ring are roughened by blasting or other processes to ensure adhesion of the insulating coating, the uniform inclination direction of the grooves strengthens the adhesion between the resin insulating coating and the metal, significantly reducing damage and peeling of the resin insulating coating and improving the insulation performance of the insulated bearing.

[0020] The anchor recess formed on the outer peripheral surface of the outer ring is provided obliquely toward the center line side in the width direction of the outer ring in a cross section along the bearing axis direction of the outer ring. Therefore, the inclination direction of the anchor recess and the shrinkage direction of the resin insulating coating during manufacturing are substantially the same, enhancing the mechanical anchor effect and improving the adhesion of the resin insulating coating to the outer peripheral surface compared to the case where the anchor recess is formed perpendicular to the outer peripheral surface.

[0021] Also, the anchor recess formed on the end face of the outer ring is provided obliquely toward the outer peripheral surface side in a cross section along the bearing axis direction of the outer ring. Therefore, the inclination direction of the anchor recess and the shrinkage direction of the resin insulating coating during manufacturing are substantially the same, enhancing the mechanical anchor effect and improving the adhesion of the resin insulating coating to the end face compared to the case where the anchor recess is formed perpendicular to the end face.

[0022] The anchor recess formed on the outer peripheral surface of the outer ring is, for example, a groove, and is provided, for example, in a ring shape continuously over the entire circumference in the circumferential direction of the outer peripheral surface. However, it is not limited to a ring-shaped groove continuous over the entire circumference, and a plurality of linear grooves formed in the circumferential direction may be arranged on the same line in the circumferential direction. Also, a plurality of ring-shaped grooves or grooves arranged on the same line in the circumferential direction may be provided side by side in the width direction of the outer peripheral surface. Furthermore, it is not limited to a groove, and holes or the like may also be used.

[0023] Also, the anchor recess formed on the end face of the outer ring is, for example, a groove, and is provided, for example, in a ring shape continuously over the entire circumference in the circumferential direction of the end face. However, it is not limited to a ring-shaped groove continuous over the entire circumference, and a plurality of linear grooves formed in the circumferential direction may be arranged on the same line in the circumferential direction. Also, a plurality of ring-shaped grooves or grooves arranged on the same line in the circumferential direction may be provided side by side in the radial direction of the end face. Furthermore, it is not limited to a groove, and holes or the like may also be used.

[0024] Here, on the outer peripheral surface of the outer ring, the inclination angle θ1 of the anchor recess in the cross-section along the bearing axis direction of the outer ring is preferably in the range of 20 degrees to 60 degrees with respect to the perpendicular line of the outer peripheral surface and towards the center line side. If it is within this range, the anchor recess is substantially in line with the shrinkage direction of the resin insulating coating during manufacturing, and a mechanical anchor effect can be effectively produced, and the adhesion between the resin insulating coating and the outer peripheral surface of the outer ring can be further improved.

[0025] Also, on the end face of the outer ring, the inclination angle θ2 of the anchor recess in the cross-section along the bearing axis direction of the outer ring is preferably in the range of 20 degrees to 60 degrees with respect to the perpendicular line of the end face and towards the outer peripheral surface side. If it is within this range, the anchor recess is substantially in line with the shrinkage direction of the resin insulating coating during manufacturing, and a mechanical anchor effect can be effectively produced, and the adhesion between the resin insulating coating and the outer peripheral surface of the outer ring can be further improved.

[0026] Also, when forming anchor recesses with inclinations on the outer peripheral surface and end face of the outer ring, the inclination angle θ1 of the anchor recess formed on the outer peripheral surface is in the range of 20 degrees to 60 degrees with respect to the perpendicular line of the outer peripheral surface and towards the center line side in the width direction of the outer ring in the cross-section along the bearing axis direction of the outer ring, and the inclination angle θ2 of the anchor recess formed on the end face is in the range of 20 degrees to 60 degrees with respect to the perpendicular line of the end face and towards the outer peripheral surface side in the cross-section along the bearing axis direction of the outer ring. If it is within these ranges, the anchor recess is substantially in line with the shrinkage direction of the resin insulating coating during manufacturing, and a mechanical anchor effect can be effectively produced, and the adhesion between the resin insulating coating and the outer peripheral surface or end face of the outer ring can be further improved.

[0027] Since the outer peripheral surface and the end face of the outer ring have anchor recesses, the area where the side wall portion of the resin insulating coating contacts the anchor recess can be ensured, and thus it can adhere firmly compared to those having anchor recesses only on the outer peripheral surface or the end face.

[0028] Furthermore, the insulating bearing of the present invention is a bearing comprising a plurality of rolling elements between a metal outer ring and an inner ring, wherein the inner ring has anchor recesses formed by laser processing on its inner circumferential surface and end face, and a resin insulating coating that covers the inner circumferential surface and end face of the inner ring and has a hardened bonding portion that fits into the anchor recess, wherein the anchor recesses formed on the inner circumferential surface are provided at an angle toward the centerline in the width direction of the inner ring in a cross section along the bearing axis direction of the inner ring, and the anchor recesses formed on the end face are provided at an angle toward the inner circumferential surface in a cross section along the bearing axis direction of the inner ring.

[0029] By forming inclined anchor recesses on the inner circumference and end faces of the metal inner ring, a portion of the resin insulating coating penetrates the anchor recesses and adheres closely to the side walls within the recesses, thereby increasing the contact area between the metal on the inner circumference and the metal on the end faces. As a result, the adhesion between the resin insulating coating and the metal becomes stronger than when the inner circumference and end faces of the inner ring are roughened by blasting or other processes to ensure adhesion of the insulating coating. This significantly reduces damage and peeling of the resin insulating coating, improving the insulation performance of the insulated bearing.

[0030] The anchor recess formed on the inner circumferential surface of the inner ring is positioned at an angle toward the centerline in the width direction of the inner ring in a cross-section along the bearing axis direction of the inner ring. As a result, the inclination direction of the anchor recess and the shrinkage direction of the resin insulating coating during manufacturing almost coincide, which enhances the mechanical anchoring effect and improves the adhesion of the resin insulating coating to the inner circumferential surface compared to when the anchor recess is formed perpendicular to the inner circumferential surface.

[0031] Furthermore, since the anchor recess formed on the end face of the inner ring is positioned at an angle toward the inner circumferential surface in a cross-section along the bearing axis direction of the inner ring, the direction of inclination of the anchor recess and the direction of shrinkage of the resin insulating coating during manufacturing almost coincide. This enhances the mechanical anchoring effect and improves the adhesion of the resin insulating coating to the end face compared to when the anchor recess is formed perpendicular to the end face.

[0032] The anchor recess formed on the inner circumferential surface of the inner ring is, for example, a groove, and is provided in a continuous ring shape over the entire circumference in the circumferential direction of the inner circumferential surface. However, it is not limited to a continuous ring-shaped groove over the entire circumference, and multiple linear grooves formed in the circumferential direction may be arranged on the same line in the circumferential direction. Furthermore, multiple ring-shaped grooves or grooves arranged on the same line in the circumferential direction may be arranged in the width direction of the inner circumferential surface. Moreover, it is not limited to grooves, but may also be a hole or the like.

[0033] Furthermore, the anchor recess formed on the end face of the inner ring is, for example, a groove, and is provided in a continuous ring shape over the entire circumference in the circumferential direction of the end face. However, it is not limited to a continuous ring-shaped groove over the entire circumference, and multiple linear grooves formed in the circumferential direction may be arranged on the same line in the circumferential direction. Alternatively, multiple ring-shaped grooves or grooves arranged on the same line in the circumferential direction may be arranged in the radial direction of the end face. Moreover, it is not limited to grooves, but may also be a hole or the like.

[0034] Here, the inclination angle θ3 of the anchor recess formed on the inner circumferential surface is preferably in the range of 20 to 60 degrees toward the centerline in the width direction of the inner ring with respect to the perpendicular to the inner circumferential surface in a cross-section along the bearing axis direction of the inner ring, and the inclination angle θ4 of the anchor recess formed on the end face is preferably in the range of 20 to 60 degrees toward the inner circumferential surface with respect to the perpendicular to the end face in a cross-section along the bearing axis direction of the inner ring. Within these ranges, the anchor recess substantially coincides with the shrinkage direction of the resin insulating coating during manufacturing, which allows for a particularly effective mechanical anchoring effect and further improves the adhesion between the resin insulating coating and the inner circumferential surface or end face of the inner ring.

[0035] Since anchor recesses are formed on the inner circumferential surface and end face of the inner ring by laser processing, a contact area is secured between the resin insulating coating and the side walls of the anchor recesses. Therefore, the resin insulating coating and the inner ring can adhere firmly. Furthermore, even without the recesses on the end face described in Japanese Patent Application Publication No. 2002-147466, the anchor recesses formed on the end face ensure a firm adhesion between the resin insulating coating and the end face of the inner ring, preventing peeling of the resin insulating coating from the edges.

[0036] Furthermore, the depth of the anchor recess is preferably in the range of 20 μm to 100 μm. This is because within this range, a sufficient area of ​​the side walls within the anchor recess that adheres to the resin insulating coating can be secured. While a deeper anchor recess is preferable because it makes it easier to secure a sufficient area of ​​the side walls within the anchor recess that adheres to the resin insulating coating, a deeper anchor recess increases the processing time required for processing the anchor recess. Therefore, a balance between adhesion to the resin insulating coating and the processing time (groove processing time) is important, and considering this balance, a depth of 30 μm to 60 μm is particularly preferable for the anchor recess.

[0037] If this depth falls below 20 μm, there is a risk that sufficient surface area of ​​the side walls within the anchor recess, to which the resin insulating coating adheres, may not be secured. This could reduce the anchoring effect of the resin insulating coating in the extraction direction, making it impossible to ensure proper adhesion.

[0038] On the other hand, increasing the depth of the anchor recess increases the number of processing steps required. Furthermore, if the anchor recess is processed to be deeper than necessary, not only will the processing steps increase, but there is also a concern that the strength of the base metal will decrease. For this reason, the depth of the anchor recess (depth of the opened groove) is preferably in the range of 20 μm to 100 μm.

[0039] Furthermore, it is preferable that the anchor recesses are spaced between 100 μm and 800 μm apart. If the spacing of the anchor recesses is less than 100 μm, the difficulty of laser processing increases, and the number of steps required to form the anchor recesses (groove processing steps) may increase. On the other hand, if the spacing of the anchor recesses exceeds 800 μm, the number of anchor recesses that can be formed will decrease. A spacing between 100 μm and 800 μm is preferable because it allows for sufficient area of ​​the side walls within the anchor recesses to which the resin insulating coating adheres.

[0040] Furthermore, it is preferable that the anchor recess is a circumferential groove formed in the circumferential direction. In this case, the area of ​​the groove that contacts the resin insulating coating is increased, and the bonding strength between the outer ring or inner ring and the resin insulating coating is improved.

[0041] Furthermore, it is preferable that the anchor recess is a grid-like groove having circumferential grooves formed in the circumferential direction and grooves intersecting the circumferential grooves. In this case, the area of ​​the grooves in contact with the resin insulating coating is further increased, and the bonding strength between the outer ring or inner ring and the resin insulating coating is further improved. [Effects of the Invention]

[0042] According to the present invention, it is easy to process anchor recesses into the outer and inner rings. Furthermore, it is possible to improve the adhesion of the resin insulating coating to the outer and inner rings. [Brief explanation of the drawing]

[0043] [Figure 1] This is a cross-sectional view along the bearing axial direction, showing an example of an embodiment of the insulating bearing of the present invention, in which a resin insulating coating is provided on the outer circumferential surface of the outer ring and an anchor recess is formed on the outer circumferential surface of the outer ring. [Figure 2] This is a cross-sectional view showing anchor recesses provided in the outer and inner rings. [Figure 3] This is a schematic diagram illustrating the inclination of the anchor recesses in each section. [Figure 4] This is an explanatory diagram showing the direction of thermal contraction of the resin insulating coating during the cooling process in manufacturing. [Figure 5] This is a cross-sectional view along the bearing axis direction, showing an example of an embodiment of the insulating bearing of the present invention, in which a resin insulating coating is provided on the outer circumferential surface of the outer ring and an anchor recess is formed on the end face of the outer ring. [Figure 6] This is a cross-sectional view along the bearing axial direction, showing an example of an embodiment of the insulating bearing of the present invention, in which a resin insulating coating is provided on the outer circumferential surface of the outer ring, and anchor recesses are formed on the outer circumferential surface and end face of the outer ring. [Figure 7]This is a cross-sectional view along the bearing axial direction, showing an example of an embodiment of the insulating bearing of the present invention, in which a resin insulating coating is provided on the inner circumferential surface of the inner ring, and anchor recesses are formed on the inner circumferential surface and end face of the inner ring. [Figure 8] This is a cross-sectional view along the bearing axial direction, showing an example of an embodiment of the insulating bearing of the present invention, in which a resin insulating coating is provided on the outer circumferential surface of the outer ring and the inner circumferential surface of the inner ring, and anchor recesses are formed on the outer circumferential surface and end face of the outer ring and the inner circumferential surface and end face of the inner ring. [Figure 9] The following figures show the results of analyses performed under different conditions regarding the adhesion between the outer ring and the resin insulating coating: (A) shows the results of the analysis under inclination angle condition a, (B) shows the results of the analysis under inclination angle condition b, (C) shows the results of the analysis under inclination angle condition c, (D) shows the results of the analysis under inclination angle condition d, (E) shows the results of the analysis under inclination angle condition e, (F) shows the results of the analysis under inclination angle condition f, and (G) shows the results of the analysis under inclination angle condition g. [Figure 10] The following figures show the results of analyses performed under different conditions regarding the adhesion between the inner ring and the resin insulating coating: (H) shows the results of the analysis under inclination angle condition h, (I) shows the results of the analysis under inclination angle condition i, (J) shows the results of the analysis under inclination angle condition j, (K) shows the results of the analysis under inclination angle condition k, (L) shows the results of the analysis under inclination angle condition l, (M) shows the results of the analysis under inclination angle condition m, and (N) shows the results of the analysis under inclination angle condition n. [Modes for carrying out the invention]

[0044] Hereinafter, an example of an embodiment of the insulating bearing according to the present invention will be described with reference to the drawings. Figures 1 and 2 show an insulated bearing according to the present invention. The insulated bearing 1 is a rolling bearing comprising a plurality of rolling elements 6 between a metal outer ring 2 and an inner ring 3, where the rolling elements 6 are, for example, ball bearings. However, it is not limited to ball bearings, and may also be a roller bearing, for example. Furthermore, the insulated bearing 1 in this embodiment is a radial rolling bearing, but it is not limited to this, and may also be a thrust rolling bearing, for example. Each rolling element 6 is held at a predetermined interval by a cage 11. The inner circumference side of the outer ring 2 is the outer ring raceway surface 4 that contacts the rolling elements 6, and the outer circumference side of the inner ring 3 is the inner ring raceway surface 5 that contacts the rolling elements 6.

[0045] The insulated bearing 1 is provided, for example, between a housing (not shown) and a rotating shaft (not shown). A resin insulating coating 9 is provided on either the outer circumferential surface 7 of the outer ring 2 that contacts the housing, or the inner circumferential surface 8 of the inner ring 3 that contacts the rotating shaft, or on both the outer circumferential surface 7 and the inner circumferential surface 8. Here, the outer circumferential surface 7 of the outer ring 2 is the outer circumferential surface 7a and end face 7b, which are the surfaces opposite to the outer ring raceway surface 4, and the inner circumferential surface 8 of the inner ring 3 is the inner circumferential surface 8a and end face 8b, which are the surfaces opposite to the inner ring raceway surface 5.

[0046] When a resin insulating coating 9 is provided on the outer circumferential surface 7 of the outer ring 2, an anchor recess 10 is formed on either the outer circumferential surface 7a or the end face 7b of the outer ring 2, or on both the outer circumferential surface 7a and the end face 7b, by laser processing. Similarly, when a resin insulating coating 9 is provided on the inner circumferential surface 8 of the inner ring 3, an anchor recess 10 is formed on both the inner circumferential surface 8a and the end face 8b of the inner ring 3 by laser processing. During the manufacturing of the insulated bearing 1, a portion of the resin insulating coating 9 enters the anchor recess 10 to form a joint 9a, improving the adhesion between the outer ring 2 and the inner ring 3 and the resin insulating coating 9. In other words, the resin insulating coating 9 has a joint 9a that has entered and hardened in the anchor recess 10.

[0047] (Embodiment 1) An insulated bearing 1 is described, which has an anchor recess 10 formed on the outer circumferential surface 7a of the outer ring 2 and a resin insulating coating 9 provided on the outer circumferential surface 7 of the outer ring 2. Figures 1 and 2 show an insulated bearing 1. The insulated bearing 1 comprises a plurality of rolling elements 6 between a metal outer ring 2 and an inner ring 3. It includes an anchor recess 10 formed by laser processing on the outer circumferential surface 7a of the outer ring 2, and a resin insulating coating 9 that covers at least the outer circumferential surface 7a of the outer ring 2 and has a hardened joint portion 9a that fits into the anchor recess 10. The anchor recess 10 is provided at an angle toward the center line 12 in the width direction of the outer ring 2 in a cross section along the bearing axis direction of the outer ring 2 (the direction of the central axis 17 of the bearing 1). In this embodiment, both the outer circumferential surface 7a and the end face 7b are covered with the resin insulating coating 9 in order to ensure sufficient contact area between the resin insulating coating and the outer ring 2, but a configuration in which only the outer circumferential surface 7a is covered is also acceptable.

[0048] The anchor recesses 10 are formed by laser processing, and are grooves formed by continuously or intermittently irradiating the outer ring 2 with laser light while rotating or moving it axially. However, they are not limited to grooves; holes formed by irradiating the laser in a point-like manner are also acceptable. Multiple anchor recesses 10 are formed on the outer circumferential surface 7a of the outer ring 2. That is, a sufficient number are formed to bond the resin insulating coating 9 by the anchoring effect. The method of processing the anchor recesses by laser irradiation described above is just one example of a preferred form, but is not limited to this, and other laser irradiation methods may be used.

[0049] When forming the anchor recess 10, the laser beam is irradiated onto the outer surface 7a from an oblique direction, so that the anchor recess 10 is positioned obliquely toward the center line 12 in the width direction of the outer ring 2 in a cross section along the bearing axis direction of the outer ring 2.

[0050] Figure 3 schematically shows the inclination of the anchor recesses 10 in each section. For ease of understanding, the number of anchor recesses 10 has been reduced and the figure has been enlarged. Also, the hatching indicating the cross-section has been omitted.

[0051] Furthermore, Figure 4 shows the direction of thermal contraction of the resin insulating coating 9 during the cooling process during manufacturing. As indicated by the arrows in the figure, in a cross-section along the bearing axis direction of the outer ring 2, the resin insulating coating 9 covering the outer circumferential surface 7 of the outer ring 2 contracts radially outward in the portion corresponding to the end face 7b, and contracts toward the center line 12 in the portion corresponding to the outer circumferential surface 7a. In addition, although not shown in the figure, it also contracts radially inward overall.

[0052] As shown in Figure 3, among the anchor recesses 10 provided on the outer circumferential surface 7a of the outer ring 2, the anchor recess 10 located to the right of the center line 12 in the figure is tilted to the left at an angle θ1 so that its bottom is closer to the center line 12, and the anchor recess 10 located to the left of the center line 12 in the figure is tilted to the right at an angle θ1 so that its bottom is closer to the center line 12. By tilting the anchor recesses 10 in this way, during the manufacturing of the insulated bearing 1, the difference in thermal expansion and contraction between the resin insulating coating 9 and the outer ring 2 during the molding of the resin insulating coating 9 can be used to make the joint portion 9a of the resin insulating coating 9 bite deeper into the anchor recess 10, thereby increasing the anchoring effect and making the resin insulating coating 10 adhere more tightly to the outer circumferential surface 7a.

[0053] Here, in the cross-section of the outer ring 2 along the bearing axis direction, the inclination angle θ1 of the anchor recess 10 is preferably set in the range of 20 to 60 degrees (20 degrees ≤ θ1 ≤ 60 degrees) toward the center line 12 with respect to the perpendicular 13 of the outer circumferential surface 7a. This range allows for the efficient generation of a force that pushes the joint 9a into the back of the anchor recess 10 by utilizing the shrinkage of the resin insulating coating 9 during molding. As a result, a more effective mechanical anchoring effect can be generated, further improving the adhesion between the resin insulating coating 9 and the outer ring 2. However, the inclination angle θ1 may be less than 20 degrees, or greater than 60 degrees.

[0054] Furthermore, the depth D of the anchor recess 10 is preferably set in the range of 20 μm to 100 μm (20 μm ≤ D ≤ 100 μm). By setting it within this range, sufficient area of ​​the side wall portion 10a within the anchor recess 10 that is in close contact with the joint portion 9a of the resin insulating coating 9 can be secured. If the depth D of the anchor recess 10 is less than 20 μm, there is a risk that sufficient area of ​​the side wall portion 10a within the anchor recess 10 that is in close contact with the joint portion 9a cannot be secured. There is a risk that the anchoring effect in the direction of extraction of the joint portion 9a will decrease and the adhesion will decrease. On the other hand, if the depth D of the anchor recess 10 is increased, the number of processing steps will increase. Also, if the anchor recess 10 is processed to be deeper than necessary, not only will the number of processing steps increase, but there is also a concern that the metal strength of the outer ring 2, which is the base material, will decrease. Therefore, in order to balance these factors, the depth D is preferably in the range of 20 μm to 100 μm.

[0055] Increasing the depth D of the anchor recess 10 increases the area of ​​the side wall portion 10a within the anchor recess 10 that is in close contact with the joint portion 9a. However, this also increases the processing time required for the anchor recess 10. Therefore, a balance between adhesion with the resin insulating coating 10 and the processing time is important, and considering this balance, a depth D of the anchor recess 10 is more preferably in the range of 30 μm to 60 μm (30 μm ≤ D ≤ 60 μm).

[0056] Multiple anchor recesses 10 are provided on the outer circumferential surface 7a of the outer ring 2. The anchor recesses 10 are preferably provided at intervals L of, for example, 100 μm to 800 μm (Figure 2). Here, the interval L of the anchor recesses 10 refers to the distance from the center of the opening of one anchor recess 10 to the center of the opening of the adjacent anchor recess 10. If the interval L of the anchor recesses 10 is less than 100 μm, the difficulty of laser processing increases, and the number of steps required to form the anchor recesses 10 (groove processing steps) may increase. On the other hand, if the interval L of the anchor recesses 10 exceeds 800 μm, the number of anchor recesses 10 to be formed decreases. To balance these factors, the interval L is preferably in the range of 100 μm to 800 μm. By setting the spacing L of the anchor recesses 10 to a range of 100 μm to 800 μm, sufficient anchor recesses 10 can be formed on the outer surface 7a, and a sufficient area for the resin insulating coating 9 to contact the outer ring 2 can be secured.

[0057] Furthermore, considering the balance between the processing time required for the anchor recess 10 and the contact area between the resin insulating coating, 9, and the outer ring 2, the spacing L of the anchor recess 10 is more preferably in the range of 300 μm to 500 μm.

[0058] The spacing L of the anchor recesses 10 may be equal or irregular. Furthermore, the anchor recesses 10 may be evenly distributed across the entire outer surface 7a, or concentrated in certain areas. The arrangement of the anchor recesses 10 can be adjusted according to the desired performance. However, it is preferable to provide anchor recesses 10 on both sides of the center line 12. Additionally, providing anchor recesses 10 at equal intervals across the entire surface is preferable from the standpoint of ensuring balanced and tight contact between the resin insulating coating 9 and the outer ring 2.

[0059] The width W of the opening of the anchor recess 10 is set to a range of, for example, 20 μm to 80 μm. When the width W of the opening of the anchor recess 10 is within the range of 20 μm to 80 μm, a portion of the resin insulating coating 9 enters the anchor recess 10 and adheres closely to its side wall portion 10a, thereby ensuring a sufficient contact area.

[0060] Here, if the width W of the opening of the anchor recess 10 is less than 20 μm, the resin material will have difficulty entering the interior of the anchor recess 10 during the molding of the resin insulating coating 9. Furthermore, if the width W of the opening of the anchor recess 10 is less than 10 μm, the resin material will have significantly more difficulty entering the interior of the anchor recess 10, which may result in insufficient contact area between the joint 9a and the side wall portion 10a inside the anchor recess 10. On the other hand, if the width W of the opening of the anchor recess 10 exceeds 80 μm, the resin material will enter the interior of the anchor recess 10 more easily, but the number of steps required to process the anchor recess 10 will increase. Therefore, the width W is preferably in the range of 10 μm to 80 μm, and more preferably in the range of 20 μm to 80 μm.

[0061] The resin insulating coating 9 is provided on the outer circumferential surface 7 (outer circumferential surface 7a and end surface 7b) of the outer ring 2, for example, by injection molding. During injection molding, a portion of the resin material enters the anchor recess 10 and hardens within the anchor recess 10 to form the joint 9a. As the material for the resin insulating coating 9, thermosetting resins such as polyimide, epoxy resin, and phenolic resin, or thermoplastic resins such as polyethylene, acrylic resin, polyamide (polyamide 6,6, polyamide 6), polyester resin (polybutylene terephthalate, polyethylene terephthalate), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK) can be used.

[0062] The thickness of the resin insulating coating 9 is set considering, for example, insulation properties and clearance with mounting members (e.g., housing). A thickness of, for example, 0.1 mm to 3.0 mm is preferable from the viewpoint of insulation properties and residual stress. A thickness of 0.5 mm to 3.0 mm is particularly preferable because it increases long-term reliability. On the other hand, if the thickness of the resin insulating coating 9 is 4.0 mm or more, residual stress tends to increase, potentially leading to delamination.

[0063] The insulating bearing 1 has a resin insulating coating 9 on the outer circumferential surface 7 of the outer ring 2, so that the housing and the outer ring 2 are electrically insulated, and galvanic corrosion of the insulating bearing 1 can be prevented. In addition, an anchor recess 10 is provided on the outer circumferential surface 7a of the outer ring 2, and the anchor recess 10 is given an inclination angle θ1, so that the adhesion of the resin insulating coating 9 to the outer ring 2 can be improved. Furthermore, since the anchor recess 10 is laser processed, the processing of the anchor recess 10 can be performed with high precision.

[0064] (Embodiment 2) Next, we will describe an insulated bearing 1 in which an anchor recess 10 is formed on the end face 7b of the outer ring 2 and a resin insulating coating 9 is provided on the outer circumferential surface 7 of the outer ring 2. The depth D, spacing L, and opening width W of the anchor recess 10 are the same as those of the insulating bearing 1 described above, so their explanation is omitted. Similarly, the resin insulating coating 9 is the same as that of the insulating bearing 1 described above, so its explanation is omitted.

[0065] Figure 5 shows an insulated bearing 1. The insulated bearing 1 comprises a plurality of rolling elements 6 between a metal outer ring 2 and an inner ring 3, and includes an anchor recess 10 formed by laser processing on the end face 7b of the outer ring 2, and a resin insulating coating 9 that covers the outer circumferential surface 7a and end face 7b of the outer ring 2 and has a hardened joint portion 9a that fits into the anchor recess 10. The anchor recess 10 is provided at an angle toward the outer circumferential surface 7a in a cross section along the bearing axis direction of the outer ring 2.

[0066] The anchor recesses 10 are formed by laser processing, and are grooves formed by continuously or intermittently irradiating the outer ring 2 with laser light while rotating or moving it axially. However, they are not limited to grooves; holes formed by irradiating the laser in a point-like manner are also acceptable. Multiple anchor recesses 10 are formed on the end face 7b of the outer ring 2. That is, a sufficient number are formed to bond the resin insulating coating 9 by the anchor effect. The method of processing the anchor recesses by laser irradiation described above is just one example of a preferred form, but is not limited to this, and other laser irradiation methods may be used.

[0067] When forming the anchor recess 10, the laser beam is irradiated from an oblique direction to the end face 7b, so that the anchor recess 10 is positioned obliquely toward the outer circumferential surface 7a in a cross section along the bearing axis direction of the outer ring 2. That is, in Figure 3, the anchor recess 10 is inclined at an angle θ2 toward the outer circumferential surface 7a with respect to the perpendicular line 14 of the end face 7b. By inclining the anchor recess 10 in this way, during the manufacturing of the insulated bearing 1, the difference in thermal expansion and contraction between the resin insulating coating 9 and the outer ring 2 during the molding of the resin insulating coating 9 can be used to make the joint portion 9a of the resin insulating coating 9 bite deeper into the anchor recess 10, thereby increasing the anchoring effect and making the resin insulating coating 10 adhere more tightly to the end face 7b.

[0068] Here, the inclination angle θ2 of the anchor recess 10 in the cross-section of the outer ring 2 along the bearing axis direction is preferably set to a range of, for example, 20 to 60 degrees toward the outer circumferential surface 7a with respect to the perpendicular 14 of the end face 7b (20 degrees ≤ θ2 ≤ 60 degrees). This range allows for the generation of a force that pushes the joint 9a into the back of the anchor recess 10 by utilizing the shrinkage of the resin insulating coating 9 during molding. As a result, a more effective mechanical anchoring effect can be produced, further improving the adhesion between the resin insulating coating 9 and the outer ring 2. However, the inclination angle θ2 may be less than 20 degrees, or greater than 60 degrees.

[0069] Since the insulating bearing 1 has a resin insulating coating 9 on the outer circumferential surface 7 of the outer ring 2, the housing and the outer ring 2 can be electrically insulated, preventing electrolytic corrosion of the insulating bearing 1. In addition, an anchor recess 10 is provided on the end face 7b of the outer ring 2, and the anchor recess 10 is given an inclination angle θ2, which improves the adhesion of the resin insulating coating 9 to the outer ring 2. Furthermore, since the anchor recess 10 is laser processed, the processing of the anchor recess 10 can be performed with high precision. In addition, even without the recess on the end face described in Japanese Patent Application Publication No. 2002-147466, etc., the anchor recess 10 formed on the end face allows the resin insulating coating 9 and the end face of the outer ring 2 to adhere firmly, preventing peeling of the resin insulating coating 9 from the edge.

[0070] (Embodiment 3) Next, we will describe an insulated bearing 1 in which anchor recesses 10 are formed on the outer circumferential surface 7a and end face 7b of the outer ring 2, and a resin insulating coating 9 is provided on the outer circumferential surface 7 of the outer ring 2. Note that the anchor recess 10 formed on the outer peripheral surface 7a of the outer ring 2 is the same as the anchor recess 10 in Embodiment 1, and the anchor recess 10 formed on the end face 7b is the same as the anchor recess 10 in Embodiment 2, so their descriptions are omitted. Also, the resin insulating coating 9 is the same as the resin insulating coating 9 in Embodiment 1 and Embodiment 2, so its description is omitted.

[0071] Figure 6 shows an insulated bearing 1. The insulated bearing 1 comprises a plurality of rolling elements 6 between a metal outer ring 2 and an inner ring 3, and includes anchor recesses 10 formed by laser processing on the outer circumferential surface 7a and end face 7b of the outer ring 2, and a resin insulating coating 9 that covers the outer circumferential surface 7a and end face 7b of the outer ring 2 and has a hardened joint portion 9a that fits into the anchor recesses 10. The anchor recesses 10 formed on the outer circumferential surface 7a are provided at an angle toward the center line 12 in the width direction of the outer ring 2 in a cross section along the bearing axis direction of the outer ring 2, and the anchor recesses 10 formed on the end face 7b are provided at an angle toward the outer circumferential surface 7a in a cross section along the bearing axis direction of the outer ring 2.

[0072] The insulating bearing 1 has a resin insulating coating 9 on the outer circumferential surface 7 of the outer ring 2, so that the housing and the outer ring 2 are electrically insulated, and galvanic corrosion of the insulating bearing 1 can be prevented. In addition, anchor recesses 10 are provided on the outer circumferential surface 7a and the end face 7b of the outer ring 2, and the anchor recess 10 on the outer circumferential surface 7a is given an inclination angle θ1, and the anchor recess 10 on the end face 7b is given an inclination angle θ2, so that the adhesion of the resin insulating coating 9 to the outer ring 2 can be improved. Furthermore, since the anchor recesses 10 are laser processed, the processing of the anchor recesses 10 can be performed with high precision.

[0073] The outer circumferential surface 7a and end face 7b of the outer ring 2 have anchor recesses 10, and the resin insulating coating 9 fits into these anchor recesses 10, allowing it to adhere firmly to the outer circumferential surface 7a and end face 7b. Furthermore, even without the recesses on the end face described in Japanese Patent Application Publication No. 2002-147466, the anchor recesses 10 formed on the end face allow the resin insulating coating 9 to adhere firmly to the end face of the outer ring 2, preventing peeling of the resin insulating coating 9 from the edges.

[0074] (Embodiment 4) Next, we will describe an insulated bearing 1 in which anchor recesses 10 are formed on the inner circumferential surface 8a and end face 8b of the inner ring 3 and a resin insulating coating 9 is provided on the inner circumferential surface 8 of the inner ring 3. The depth D, spacing L, and opening width W of the anchor recess 10 are the same as those of the insulating bearing 1 described above, so their explanation will be omitted.

[0075] Figure 7 shows an insulated bearing 1. The insulated bearing 1 comprises a plurality of rolling elements 6 between a metal outer ring 2 and an inner ring 3, and includes anchor recesses 10 formed by laser processing on the inner circumferential surface 8a and end face 8b of the inner ring 3, and a resin insulating coating 9 that covers the inner circumferential surface 8a and end face 8b of the inner ring 3 and has a hardened joint portion 9a that fits into the anchor recesses 10. The anchor recesses 10 formed on the inner circumferential surface 8a are provided at an angle toward the center line 12 in the width direction of the inner ring 3 in a cross section along the bearing axis direction of the inner ring 3, and the anchor recesses 10 formed on the end face 8b are provided at an angle toward the inner circumferential surface 8a in a cross section along the bearing axis direction of the inner ring 3.

[0076] Furthermore, Figure 4 shows the direction of thermal contraction of the resin insulating coating 9 during the cooling process during manufacturing. As indicated by the arrows in the figure, in a cross-section along the bearing axis direction of the inner ring 3, the resin insulating coating 9 covering the inner circumferential surface 8 of the inner ring 3 contracts radially inward in the portion corresponding to the end face 8b, and contracts toward the center line 12 in the portion corresponding to the inner circumferential surface 8a. In addition, although not shown in the figure, it also contracts radially inward overall.

[0077] The anchor recesses 10 are formed by laser processing, for example, by continuously or intermittently irradiating the inner ring 3 with laser light while rotating or moving it axially. However, they are not limited to grooves; holes formed by irradiating with a laser in a point-like manner are also acceptable. Multiple anchor recesses 10 are formed on the inner circumferential surface 8a and end face 8b of the inner ring 3. That is, a sufficient number are formed to bond the resin insulating coating 9 by the anchor effect. The laser processing method described above is just one example of a preferred form, but is not limited to this, and other laser processing methods may be used.

[0078] When forming the anchor recess 10 on the inner circumferential surface 8a of the inner ring 3, the laser beam is irradiated onto the inner circumferential surface 8a from an oblique direction, so that the anchor recess 10 is positioned obliquely toward the center line 12 in the width direction of the inner ring 3 in a cross section along the bearing axis direction of the inner ring 3. That is, in Figure 3, the anchor recess 10 located to the right of the center line 12 is inclined to the left at an angle θ3, and the anchor recess 10 located to the left of the center line 12 is inclined to the right at an angle θ3. By inclining the anchor recess 10 in this way, during the manufacturing of the insulated bearing 1, the difference in thermal expansion and contraction between the resin insulating coating 9 and the inner ring 3 during the molding of the resin insulating coating 9 can be used to make the joint portion 9a of the resin insulating coating 9 bite deeper into the anchor recess 10, thereby increasing the anchoring effect and making the resin insulating coating 10 adhere more closely to the inner circumferential surface 8a.

[0079] Here, the inclination angle θ3 of the anchor recess 10 is preferably set in the range of 20 to 60 degrees (20 degrees ≤ θ3 ≤ 60 degrees) toward the center line 12 with respect to the perpendicular 16 of the inner circumferential surface 8a in a cross section along the bearing axis direction of the inner ring 3. This is because by setting it within this range, it is possible to efficiently generate a force that pushes the joint 9a into the back of the anchor recess 10 by utilizing the shrinkage during molding of the resin insulating coating 9. As a result, a mechanical anchoring effect can be generated more effectively, and the adhesion between the resin insulating coating 9 and the inner ring 3 can be further improved. However, the inclination angle θ3 may be less than 20 degrees, or greater than 60 degrees.

[0080] When forming the anchor recess 10 on the end face 8b of the inner ring 3, the laser beam is irradiated from an oblique direction to the end face 8b, so that the anchor recess 10 is positioned obliquely toward the inner circumferential surface 8a in a cross-section along the bearing axis direction of the inner ring 3. That is, in Figure 3, the anchor recess 10 is inclined at an angle θ4 toward the inner circumferential surface 8a with respect to the perpendicular line 15 of the end face 8b. By inclining the anchor recess 10 in this way, during the manufacturing of the insulated bearing 1, the difference in thermal expansion and contraction between the resin insulating coating 9 and the inner ring 3 during the molding of the resin insulating coating 9 can be used to make the joint portion 9a of the resin insulating coating 9 bite deeper into the anchor recess 10, thereby increasing the anchoring effect and making the resin insulating coating 10 adhere more tightly to the end face 8b.

[0081] Here, the inclination angle θ4 of the anchor recess 10 formed on the end face 8b of the inner ring 3 is preferably set in the range of 20 to 60 degrees (20 degrees ≤ θ4 ≤ 60 degrees) toward the inner circumferential surface 8a side with respect to the perpendicular 15 of the end face 8b in a cross section along the bearing axis direction of the inner ring 3. This is because by setting it within this range, it is possible to efficiently generate a force that pushes the joint 9a into the back of the anchor recess 10 by utilizing the shrinkage during molding of the resin insulating coating 9. As a result, a mechanical anchoring effect can be generated more effectively, and the adhesion between the resin insulating coating 9 and the inner ring 3 can be further improved. However, the inclination angle θ4 may be less than 20 degrees, or greater than 60 degrees.

[0082] The resin insulating coating 9 is provided on the inner circumferential surface 8 (inner circumferential surface 8a and end surface 8b) of the inner ring 3, for example, by injection molding. During injection molding, a portion of the resin material enters the anchor recess 10 and hardens within the anchor recess 10 to form the joint 9a. As the material for the resin insulating coating 9, thermosetting resins such as polyimide, epoxy resin, and phenolic resin, or thermoplastic resins such as polyethylene, acrylic resin, polyamide (polyamide 6,6, polyamide 6), polyester resin (polybutylene terephthalate, polyethylene terephthalate), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK) can be used.

[0083] The thickness of the resin insulating coating 9 is set considering, for example, insulation properties and clearance with mounting members (e.g., rotating shafts). A thickness of, for example, 0.1 mm to 3.0 mm is preferable from the viewpoint of insulation properties and residual stress. A thickness of 0.5 mm to 3.0 mm is particularly preferable because it increases long-term reliability. On the other hand, if the thickness of the resin insulating coating 9 is 4.0 mm or more, residual stress tends to increase, potentially leading to delamination.

[0084] The insulated bearing 1 has a resin insulating coating 9 on the inner circumferential surface 8 of the inner ring 3, which provides electrical insulation between the inner ring 3 and the rotating shaft, thus preventing electrolytic corrosion of the insulated bearing 1. In addition, anchor recesses 10 are provided on the inner circumferential surface 8a and end face 8b of the inner ring 3, and the anchor recesses 10 are given inclination angles θ3 and θ4, which improves the adhesion of the resin insulating coating 9 to the inner ring 3. Furthermore, since the anchor recesses 10 are laser-processed, the processing of the anchor recesses 10 can be performed with high precision.

[0085] (Embodiment 5) Next, we will describe an insulated bearing 1 in which anchor recesses 10 are formed on the outer circumferential surface 7a and end face 7b of the outer ring 2, a resin insulating coating 9 is provided on the outer circumferential surface 7 of the outer ring 2, anchor recesses 10 are formed on the inner circumferential surface 8a and end face 8b of the inner ring 3, and a resin insulating coating 9 is provided on the inner circumferential surface 8 of the inner ring 3. The anchor recess 10 formed on the outer circumferential surface 7a of the outer ring 2 is the same as the anchor recess 10 of Embodiment 1, and the anchor recess 10 formed on the end face 7b is the same as the anchor recess 10 of Embodiment 2, so their descriptions are omitted. Also, the anchor recess 10 formed on the inner circumferential surface 8a and end face 8b of the inner ring 3 is the same as the anchor recess 10 of Embodiment 4, so their descriptions are also omitted. Furthermore, the resin insulating coating 9 is the same as the resin insulating coating 9 described above, so its description is also omitted.

[0086] Figure 8 shows an insulated bearing 1. The insulated bearing 1 comprises a plurality of rolling elements 6 between a metal outer ring 2 and an inner ring 3, and includes anchor recesses 10 formed by laser processing on the outer circumferential surface 7a and end face 7b of the outer ring 2, a resin insulating coating 9 covering the outer circumferential surface 7a and end face 7b of the outer ring 2 and having a hardened joint portion 9a that fits into the anchor recesses 10, and anchor recesses 10 formed by laser processing on the inner circumferential surface 8a and end face 8b of the inner ring 3, and a resin insulating coating 9 covering the inner circumferential surface 8a and end face 8b of the inner ring 3 and having a hardened joint portion 9a that fits into the anchor recesses 10. The anchor recesses 10 formed on the outer circumferential surface 7a are provided at an angle toward the centerline 12 in the width direction of the outer ring 2 in a cross section along the bearing axis direction of the outer ring 2, and the anchor recesses 10 formed on the end face 7b are provided at an angle toward the outer circumferential surface 7a in a cross section along the bearing axis direction of the outer ring 2. Furthermore, the anchor recess 10 formed on the inner circumferential surface 8a is provided at an angle toward the center line 12 in the width direction of the inner ring 3 in a cross section along the bearing axis direction of the inner ring 3, and the anchor recess 10 formed on the end face 8b is provided at an angle toward the inner circumferential surface 8a in a cross section along the bearing axis direction of the inner ring 3.

[0087] Since the insulating bearing 1 is provided with a resin insulating coating 9 on the outer circumferential surface 7 of the outer ring 2 and the inner circumferential surface 8a of the inner ring 3, electrical insulation can be provided between the housing and the outer ring 2 and between the inner ring 3 and the rotating shaft, thereby preventing electrolytic corrosion of the insulating bearing 1. Furthermore, anchor recesses 10 are provided on the outer circumferential surface 7a and end face 7b of the outer ring 2, with an inclination angle θ1 on the anchor recess 10 on the outer circumferential surface 7a and an inclination angle θ2 on the anchor recess 10 on the end face 7b. In addition, anchor recesses 10 are provided on the inner circumferential surface 8a and end face 8b of the inner ring 3, with an inclination angle θ3 on the anchor recess 10 on the inner circumferential surface 8a and an inclination angle θ4 on the anchor recess 10 on the end face 8b. As a result, the adhesion of the resin insulating coating 9 to the outer ring 2 and inner ring 3 can be improved. Furthermore, since the anchor recess 10 is laser-processed, the processing of the anchor recess 10 can be performed with high precision.

[0088] The above-described embodiment is merely one example of a preferred embodiment of the present invention, and is not limited thereto. Various modifications can be made without departing from the spirit of the present invention. [Examples]

[0089] (Example 1) (Regarding the processing of the recess for anchors) Regarding laser processing conditions A Yb fiber laser was used to process the anchor recess 10. The processing conditions were a laser output of 30W, a pulse frequency of 60kHz, and a laser beam irradiation speed of 100mm / s. The depth D of the anchor recess 10 (depth D of the opened anchor recess 10) was adjusted to a range of 20μm to 100μm by changing the laser irradiation time and number of irradiations. The type of laser is not limited to the Yb fiber laser used above; YAG lasers, semiconductor lasers (GaN), carbon dioxide lasers, etc., can also be used, and either pulsed or continuous-oscillating lasers may be used. Furthermore, the output, frequency, wavelength, beam diameter, etc., when using various lasers can be set according to the metal used for the bearing and the purpose.

[0090] Regarding the machining direction of the anchor recess 10 The laser processing direction for the anchor recess 10 is not limited to the circumferential grooves formed on the outer circumferential surface 7 of the outer ring 2 and the inner circumferential surface 8 of the inner ring 3, which are formed in the circumferential direction (circumferential groove on the outer circumferential surface 7a of the outer ring 2, circumferential groove on the inner circumferential surface 8a of the inner ring 3, circumferential groove on the end face 7b of the outer ring 2, and circumferential groove on the end face 8b of the inner ring 3). Depending on the intended use and requirements, in addition to the circumferential grooves, a grid-like groove (grid groove) having grooves that intersect the circumferential grooves may also be formed. In this case, the area of ​​the grooves in contact with the resin insulating coating 9 is increased, and the bonding strength between the outer ring 2 and the inner ring 3 and the insulating coating 9 is improved, which is even more preferable.

[0091] Furthermore, the circumferential grooves do not have to be formed by continuously spaced grooves, but can also be formed by combining discontinuous grooves to create a circumferential shape. In addition, the circumferential shape can be formed by combining multiple holes instead of grooves.

[0092] • How to check the anchor recess 10 The outer ring 2 and inner ring 3 were cut to allow confirmation of the laser-processed cross-sections. The depth D of the anchor recess 10 was confirmed by observing the cross-sections of the outer circumferential surface 7 of the outer ring 2 and the inner circumferential surface 8 of the inner ring 3 using a video microscope (digital microscope) (manufactured by Keyence).

[0093] (Example 2) (Regarding the molding of the resin insulating coating 9) The resin insulating coating 9 can be formed on the outer circumferential surface 7 of the outer ring 2 and the inner circumferential surface 8 of the inner ring 3 by injection molding, press molding, etc. However, considering that the resin material can be efficiently supplied to the anchor recess 10 formed on the outer circumferential surface 7 of the outer ring 2 and the inner circumferential surface 8 of the inner ring 3, injection molding in which the outer ring 2 or inner ring 3 is inserted into a mold is preferred. The resin insulating coating 9 can be integrally molded on the outer circumferential surface 7a and end face 7b of the outer ring 2 by injection molding. Similarly, the inner circumferential surface 8a and end face 8b of the inner ring 3 can be integrally molded on the inner circumferential surface 8 by injection molding.

[0094] As resin materials used for the resin insulating coating 9, thermosetting resins such as polyimide, epoxy resin, and phenolic resin, and thermoplastic resins such as polyethylene, acrylic resin, polyamide (polyamide 6,6, polyamide 6), polyester resin (polybutylene terephthalate, polyethylene terephthalate), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK) can be used.

[0095] These resins may be used individually or mixed in combination of two or more types. Polyphenylene sulfide (PPS) is particularly preferred due to its excellent heat resistance and chemical resistance. Furthermore, by incorporating insulating inorganic materials as reinforcing agents into the resin material, a resin insulating coating 9 with excellent strength, water absorption properties, and creep resistance can be formed. Specific examples of insulating inorganic materials include glass fibers, silica, glass spheres, alumina, aluminum hydroxide, calcium hydroxide, zinc oxide, zinc carbonate, calcium carbonate, and aluminum oxide, and these can be used in fibrous or granular forms. The resin coating used for the resin insulating coating 9 has the advantage of being cheaper to produce than a ceramic coating.

[0096] Regarding the thickness of the resin insulating coating 9 The thickness of the resin insulating coating 9 can be set considering insulation properties and clearance with mounting members. The resin insulating coating 9 can be molded onto the outer circumferential surface 7 of the outer ring 2, the inner circumferential surface 8 of the inner ring 3, or both, and a thickness in the range of 0.1 mm to 3.0 mm is preferable from the viewpoint of insulation properties and residual stress. In particular, a range of 0.5 mm to 3.0 mm is preferable from the viewpoint of long-term reliability. On the other hand, if the thickness is 4.0 mm or more, residual stress tends to increase, which may lead to delamination.

[0097] Regarding the adhesion between the resin insulating coating 9 and the bearing. By utilizing the difference in thermal expansion and contraction between the resin material and the metal material of the outer ring 2 and inner ring 3, a resin insulating coating 9 is formed on the outer ring 2 (outer surface 7a, end face 7b) or inner ring 3 (inner surface 8a, end face 8b) by injection molding. The coefficient of thermal expansion is resin material > metal, meaning that the resin material expands and contracts more due to heat. Although the temperature is high during injection molding, as the temperature decreases after molding, the difference in thermal expansion and contraction between the resin material and the metal material of the outer ring 2 or inner ring 3 causes the resin material to contract significantly and adhere strongly to the metal.

[0098] (Example 3) Experimental methods and results 1.Structural analysis Regarding the relationship between the insulating coating and the bearing during temperature changes from the molding temperature to the temperature at which the bearing is removed from the mold.

[0099] The behavior of the outer ring 2 and the insulating coating 9 of an insulating bearing 1 under temperature changes after the insulating coating 9 of resin is molded onto the outer ring 2, and the behavior of the inner ring 3 and the insulating coating 9 of the insulating bearing 1 under temperature changes after the insulating coating 9 is molded onto the inner ring 3, were analyzed.

[0100] In order to prevent installation problems caused by inaccuracies in the housing or other mating components, the insulating bearing 1 requires machining the outer circumferential surface 7 of the outer ring 2 and the inner circumferential surface 8 of the inner ring 3 after the insulating coating 9 has been formed, and to make them uniform. Furthermore, it is known that if the irregularities (precision variations) after machining of the outer circumferential surface 7, which is the outer diameter of the outer ring 2, and the inner circumferential surface 8, which is the inner diameter of the inner ring 2, are kept within the JIS-1514-1 standard, then bearings with excellent precision can be manufactured.

[0101] However, in order to make the surface of the insulating coating 9 uniform by cutting, it is necessary to keep the irregularity (precision variation) of the insulating coating 9 before cutting within a certain value (reference value). The reason for this is that if this value (reference value) is significantly exceeded, it may become impossible to create an insulating bearing 1 with a uniform insulating coating 9 even after machining. If such an insulating bearing 1 is attached to a mating component such as a housing, there is a risk that malfunctions may occur due to insufficient precision of the insulating bearing 1.

[0102] In this analysis, the JIS-1514-1 standard was used as the baseline value (reference value) before cutting. This is because if the value is within the JIS-1514-1 standard before cutting, then with accurate cutting, the value will also be within the JIS-1514-1 standard after cutting, resulting in the creation of an extremely high-precision insulated bearing 1.

[0103] The sample of insulated bearing 1 used in the analysis has an inner diameter of 35 mm and an outer diameter of 62 mm. Therefore, based on the JIS-1514-1 standard, if the dimensional tolerance of the insulating coating 9 before cutting is kept to within 10 μm for the end face, 6.5 μm for the outer surface, and 6.0 μm or less for the inner surface, an insulated bearing 1 with extremely high precision can be produced.

[0104] Therefore, by setting the adhesion (gap) between the insulating bearing 1 and the insulating coating 9 before machining to the following standard, it was possible to achieve excellent dimensional accuracy in the insulating bearing 1 after machining, and this value was set as a constant value (reference value). • Constant values ​​(reference values) for outer ring 2: The end face 7b of the outer circumferential surface 7 is within 10 μm, and the outer circumferential surface 7a is within 6.5 μm. • Constant values ​​(reference values) for inner ring 3: End face 8b of inner circumference 8 is within 10 μm, inner circumference 8a is within 6.0 μm

[0105] (1) Regarding outer ring 2 An insulating coating 9 was formed on the outer circumferential surface 7 of an outer ring 2 having anchor recesses 10 (inclination angles θ1, θ2: as shown in (a) to (g) below, groove depth 30 μm, groove spacing 300 μm) processed under the laser processing conditions shown in Table 1 below. The behavior of the outer ring 2 and the insulating coating 9 was observed when the temperature of the outer ring 2 was changed from the resin molding temperature (150°C) to the temperature at which it was removed from the mold (20°C). The results are shown in Table 1 and Figure 9.

[0106] (a) Insulated bearing 1 (outer ring 2) without processing (no anchor recess 10) (b) An insulated bearing 1 (outer ring 2) with grooves machined on the outer surface 7a at an angle θ1:45 degrees and on the end surface 7b at an angle θ2:45 degrees. (c) An insulated bearing 1 (outer ring 2) with grooves machined on the outer surface 7a at an angle θ1:-45 degrees and on the end surface 7b at an angle θ2:-45 degrees. (d) Insulated bearing 1 (outer ring 2) with grooves machined only on the end face 7b at an angle θ2:45 degrees. (e) Insulated bearing 1 (outer ring 2) with grooves machined only on the outer surface 7a at an angle θ1:45 degrees. (f) Insulated bearing 1 (outer ring 2) with grooves machined only on end face 7b at an angle θ2:-45 degrees. (g) Insulated bearing 1 (outer ring 2) with grooves machined only on the outer surface 7a at an angle θ1:-45 degrees.

[0107] [Table 1]

[0108] Figure 9(A) corresponds to (a) above, Figure 9(B) to (b) above, Figure 9(C) to (c) above, Figure 9(D) to (d) above, Figure 9(E) to (e) above, Figure 9(F) to (f) above, and Figure 9(G) to (g) above. In (b), (d), and (e) above, the inclination direction of the anchor recess 10 coincides with the contraction direction of the insulating coating 9, and a mechanical anchoring effect is generated in the direction of extraction of the insulating coating 9, thus confirming sufficient adhesion (Evaluation in Table 1: ○). On the other hand, in (a), (c), (f), and (g), the outer circumferential surface 7a of the outer ring 2 had good adhesion due to shrinkage caused by the difference in thermal expansion and contraction between the resin material and the metal, but a gap was found at the interface between the end face 7b of the outer ring 2 and the insulating coating 9, indicating insufficient adhesion (Evaluation in Table 1: ×).

[0109] (2) Regarding the third internal group An insulating coating 9 was formed on the inner circumferential surface 8 of an inner ring 3 having anchor recesses 10 (inclination angles θ3, θ4: from (h) to (n) below, groove depth 30 μm, groove spacing 300 μm) processed under the laser processing conditions shown in Table 2 below. The behavior of the inner ring 3 and the insulating coating 9 was observed when the temperature of the inner ring 3 was changed from the resin molding temperature (150°C) to the temperature at which it was removed from the mold (20°C). The results are shown in Table 2 and Figure 10. • (h) Insulated bearing 1 (inner ring 3) without processing (no anchor recess 10) (i) An insulated bearing 1 (inner ring 3) with grooves machined on the inner circumferential surface 8a at an angle θ3:45 degrees and on the end surface 8b at an angle θ4:45 degrees. (j) An insulated bearing 1 (inner ring 3) with grooves machined on the inner circumferential surface 8a at an angle θ3:-45 degrees and on the end face 8b at an angle θ4:-45 degrees. (k) Insulated bearing 1 (inner ring 3) with grooves machined only on end face 8b at an angle θ4:45 degrees. (l) Insulated bearing 1 (inner ring 3) with grooves machined only on the inner surface 8a at an angle θ3:45 degrees. • Insulated bearing 1 (inner ring 3) with grooves machined only on end face 8b at an angle θ4:-45 degrees. (n) Insulated bearing 1 (inner ring 3) with grooves machined only on the inner surface 8a at an angle θ3:-45 degrees.

[0110] [Table 2]

[0111] Figure 10(H) corresponds to (h) above, Figure 10(I) to (i) above, Figure 10(J) to (j) above, Figure 10(K) to (k) above, Figure 10(L) to (l) above, Figure 10(M) to (m) above, and Figure 10(N) to (n) above. As described in (i) above, sufficient adhesion was confirmed by the fact that the inclination direction of the anchor recess 10 coincides with the contraction direction of the insulating coating 9, thereby creating a mechanical anchoring effect in the direction of extraction of the insulating coating 9 (Evaluation in Table 2: ○). On the other hand, a gap formed at the interface between the inner ring 3 and the insulating coating 9 in all cases except (i) (Evaluation in Table 2: ×). From this, it was found that the adhesion between the inner ring 3 and the insulating coating 9 is insufficient if only the shrinkage of the resin material is due to the difference in thermal expansion and contraction of the metal on the inner circumferential surface 8a of the inner ring 3 and the insulating coating 9. It is necessary to create a mechanical anchoring effect in the direction of extraction of the insulating coating 9 by aligning the inclination direction of the anchor recess 10 with the contraction direction of the insulating coating 9 on both the end face 8b and the inner circumferential surface 8a.

[0112] 2. Experimental Samples Analysis results have shown that the anchor recess 10 formed at a 45° angle on the outer circumferential surface 7a of the outer ring 2 (Table 1 (b), (e)) exhibits good adhesion. Therefore, samples were created with varying angles, groove depths, and groove spacings for forming the anchor recess 10, and the adhesion of the insulating coating 9 was confirmed.

[0113] The anchor recesses 10 formed on the outer circumferential surface 7a of the outer ring 2 were processed using a Yb fiber laser with a laser output of 30W, a pulse frequency of 60kHz, and a laser beam irradiation speed of 100mm / s. For comparison, a sample without the anchor recesses 10 was also prepared.

[0114] The processing conditions for the anchor recess 10 formed on the outer circumferential surface 7a of the outer ring 2 are shown below (Conditions 1 to 3). The anchor recess 10 is formed circumferentially (circumferential groove) on the outer circumferential surface 7a on both sides of the center line 12 in the width direction of the insulating bearing 1, and the circumferential groove is inclined in the depth direction toward the center line 12.

[0115] Condition 1: Change the angle condition. Under the conditions of groove depth 30 μm and groove spacing 300 μm, Outer rings 2 were created by machining the anchor recesses 10 at inclination angles θ1 of 60 degrees, 45 degrees, 20 degrees, and -45 degrees.

[0116] Condition 2: Change the groove depth condition. Under the conditions of an inclination angle θ1 of the anchor recess 10: 45 degrees and a spacing of 300 μm between anchor recesses 10, For the groove depth, an outer ring 2 was created by machining anchor recesses 10 at depths of 10 μm, 30 μm, 60 μm, and 100 μm from the surface.

[0117] Condition 3: Change the groove spacing condition. Under the conditions of an inclination angle θ1: 45 degrees and a groove depth of 30 μm for the anchor recess 10, An outer ring 2 was created by machining anchor recesses 10 at intervals of 100 μm, 300 μm, 800 μm, and 1500 μm.

[0118] Under each condition, the outer ring 2, with the anchor recess 10 formed, was placed in an injection molding die. Using an injection molding machine (horizontal injection molding machine, cylinder temperature 300 degrees Celsius, mold temperature 150 degrees Celsius), PPS resin was injected onto the outer circumferential surface 7 of the outer ring 2, where the anchor recess 10 was formed, thereby creating a bearing sample (outer ring 2) in which the resin and the outer ring 2 were joined.

[0119] After molding, the mold installed on one end face 7b side of the bearing sample (outer ring 2) was removed, and the end face of the bearing sample (outer ring 2) was ejected from the mold by using an ejector mechanism installed on the other end face 7b side. At this time, the insulating coating 9 applied to the outer circumferential surface 7 of the bearing sample (outer ring 2) is pushed out in contact with the mold (a mold installed for coating the outer circumferential surface), causing stress on the insulating coating 9, which can lead to damage starting from the curved portion between the outer circumferential surface 7a and the end face 7b, or damage traversing the outer circumferential surface 7a (damage in the grid direction rather than the circumferential direction).

[0120] Therefore, the adhesion between the outer ring 2 and the insulating coating 9 of the bearing sample (outer ring 2) created under conditions 1 to 3 was confirmed.

[0121] 3. Exam: Condition 1 To confirm the adhesion between the metal on the outer circumferential surface 7 of the outer ring 2 and the insulating coating 9, bearing samples (outer ring 2) having various anchor recesses 10 as described in Condition 1 were prepared, and the adhesion between the outer ring 2 and the insulating coating 9 was confirmed when removed from the mold after injection molding.

[0122] The test results are shown in Table 3. When the anchor recess 10 was machined with an inclination angle θ1 of 20 to 60 degrees, it was confirmed that there were no problems when removing it from the mold after injection molding, and that there was sufficient adhesion between the outer ring 2 and the insulating coating 9. On the other hand, in the case where the anchor recess 10 was machined at an inclination angle θ1 of -45 degrees, and in the case where the anchor recess 10 was not machined, damage (peeling) of the insulating coating 9 occurred when removing it from the mold after injection molding.

[0123] In cases where the anchor recess 10 was processed with an inclination angle θ1 of 20 to 60 degrees, the resin material entered the inclined anchor recess 10, and further, due to thermal shrinkage during the process of returning from the molding temperature to room temperature, the resin material adhered tightly to the side walls inside the inclined anchor recess 10. As a result, the adhesion between the outer ring 2 and the insulating coating 9 improved, and no damage (peeling) occurred. On the other hand, in cases where the anchor recess 10 was processed with an angle of -45 degrees, the direction of shrinkage of the inclined anchor recess 10 and the insulating coating 9 did not coincide, resulting in insufficient adhesion and damage (peeling) of the insulating coating 9. Therefore, an inclination angle θ1 of the anchor recess 10 is preferable to be between 20 and 60 degrees.

[0124] [Table 3]

[0125] 4. Examination: Condition 2 To confirm the adhesion between the metal on the outer circumferential surface 7 of the outer ring 2 and the insulating coating 9, bearing samples (outer ring 2) having various anchor recesses 10 as described in Condition 2 were prepared, and the adhesion between the outer ring 2 and the insulating coating 9 was confirmed when removed from the mold after injection molding.

[0126] The test results are shown in Table 4. When the anchor recess 10 was machined with a groove depth of 20 μm to 100 μm, it was confirmed that there were no problems when removing it from the mold after injection molding, and that the outer ring 2 and the insulating coating 9 had sufficient adhesion. On the other hand, in the case of products with a groove depth of 10 μm and a processed anchor recess 10, and in the case of products without groove processing, damage (peeling) of the resin (insulating coating 9) occurred when removed from the mold after injection molding. It was found that when the groove depth is less than 10 μm, the side wall portion 10a within the anchor recess 10 to which the insulating coating 9 adheres cannot be sufficiently secured, resulting in insufficient mechanical anchoring effect of the insulating coating 9 in the extraction direction.

[0127] Furthermore, while a groove depth exceeding 100 μm provides sufficient adhesion with the insulating coating 9, it increases the number of steps required to form the anchor recess 10 (groove processing steps). Therefore, considering both adhesion and groove processing steps, a groove depth of 20 μm to 100 μm is preferable.

[0128] [Table 4]

[0129] 5. Exam: Condition 3 To confirm the adhesion between the metal on the outer circumferential surface 7 of the outer ring 2 and the insulating coating, bearing samples (outer ring 2) having various anchor recesses 10 grooves as described in Condition 3 were prepared, and the adhesion between the outer ring 2 and the insulating coating 9 was confirmed when removed from the mold after injection molding.

[0130] The test results are shown in Table 5. For grooves (anchor recesses 10) with spacing between 100 μm and 800 μm, it was confirmed that there were no problems when removing the product from the mold after injection molding, and that the outer ring 2 and the insulating coating 9 had sufficient adhesion. On the other hand, in the cases where the anchor recesses 10 were machined with a spacing of 1500 μm and without groove machining, resin damage (peeling) occurred when removing from the mold after injection molding, indicating insufficient adhesion between the metal interface and the resin. If the spacing between the anchor recesses 10 falls below 100 μm, the processing becomes difficult, and the number of steps required to process the anchor recesses (in order to process the grooves densely) increases. On the other hand, when the spacing between the anchor recesses 10 was 1500 μm, the area in which the insulating coating 9 contacts the side wall portion 10a inside the anchor recesses 10 processed on the outer circumferential surface 7 of the bearing (outer ring 2) could not be sufficiently secured, and the insulating coating 9 was damaged when removed from the mold after injection molding. Therefore, the spacing between the anchor recesses 10 is preferably in the range of 100 μm to 800 μm.

[0131] [Table 5]

[0132] (summary) By using laser processing to set the optimal groove inclination angle, depth, groove width, and groove spacing at the interface between the outer circumferential surface 7 (outer circumferential surface 7a and end face 7b) of the metal bearing (outer ring 2) and the insulating coating 9, and at the interface between the inner circumferential surface 8 (inner circumferential surface 8A and end face 8B) of the bearing (inner ring 3) and the insulating coating 9, it was confirmed that the adhesion of the insulating coating can be improved without adhesive or metal surface treatment, thereby providing a bearing with high insulation properties. [Explanation of Symbols]

[0133] 1 Insulated bearing 2 Outer ring 3. Inner ring 4 Outer shaft raceway surface 5 Inner shaft raceway surface 6 Rolling elements 7 Outer circumferential surface 7a Outer surface 7b End face 8 Inner circumferential surface 8a Inner surface 8b End face 9. Resin insulating coating 9a Joint part 10 Anchor recess 10a Side wall portion within the anchor recess 11 Cage 12. Centerlines in the width direction of the outer and inner rings 13 Perpendicular line of the outer surface of the outer ring 14 Perpendicular line to the end face of the outer ring 15 Perpendicular line of the end face of the inner ring 16 Perpendicular line of the inner surface of the inner ring 17. Center axis of the bearing D Depth of the recess for anchors L-shaped spacing of anchor recesses Width of the opening in the recess for the W anchor θ1, θ2, θ3, θ4 Inclination angle of anchor recess

Claims

1. A bearing comprising multiple rolling elements between a metal outer ring and an inner ring, An anchor recess formed on the outer circumferential surface of the outer ring by laser processing, A resin insulating coating covering at least the outer circumferential surface of the outer ring and having a bonded portion that has hardened into the anchor recess, Equipped with, The anchor recess is provided at an angle toward the center line in the width direction of the outer ring in a cross-section along the bearing axis direction of the outer ring. An insulating bearing characterized by the following features.

2. A bearing comprising multiple rolling elements between a metal outer ring and an inner ring, An anchor recess formed by laser processing on the end face of the outer ring, A resin insulating coating covering the outer circumferential surface and end face of the outer ring, having a joint portion that has hardened into the anchor recess, Equipped with, The anchor recess is provided at an angle toward the outer circumferential surface in a cross-section along the bearing axis direction of the outer ring. An insulating bearing characterized by the following features.

3. A bearing comprising multiple rolling elements between a metal outer ring and an inner ring, The outer ring has an anchor recess formed by laser processing on its outer circumferential surface and end surface, A resin insulating coating covering the outer circumferential surface and end face of the outer ring, having a joint portion that has hardened into the anchor recess, Equipped with, The anchor recess formed on the outer circumferential surface is provided at an angle toward the center line in the width direction of the outer ring in a cross section along the bearing axis direction of the outer ring, The anchor recess formed on the end face is provided at an angle toward the outer circumferential surface in a cross-section along the bearing axis direction of the outer ring. An insulating bearing characterized by the following features.

4. The insulated bearing according to claim 1, characterized in that the inclination angle θ1 of the anchor recess in a cross-section along the bearing axis direction of the outer ring is in the range of 20 to 60 degrees toward the center line with respect to the perpendicular of the outer circumferential surface.

5. The insulating bearing according to claim 2, characterized in that the inclination angle θ2 of the anchor recess in the cross section of the outer ring along the bearing axis direction is in the range of 20 to 60 degrees toward the outer circumferential surface with respect to the perpendicular to the end face.

6. The inclination angle θ1 of the anchor recess formed on the outer circumferential surface is in the range of 20 to 60 degrees toward the center line in the width direction of the outer ring with respect to the perpendicular to the outer circumferential surface in a cross section along the bearing axis direction of the outer ring. The inclination angle θ2 of the anchor recess formed on the end face is in the range of 20 to 60 degrees toward the outer circumferential surface with respect to the perpendicular to the end face in a cross-section along the bearing axis direction of the outer ring. The insulating bearing according to claim 3, characterized in that it is as described above.

7. A bearing comprising multiple rolling elements between a metal outer ring and an inner ring, The inner ring has an anchor recess formed by laser processing on its inner circumferential surface and end surface, A resin insulating coating covering the inner circumferential surface and end face of the inner ring, having a joint that has hardened into the anchor recess, Equipped with, The anchor recess formed on the inner circumferential surface is provided at an angle toward the center line in the width direction of the inner ring in a cross section along the bearing axis direction of the inner ring, The anchor recess formed on the end face is provided at an angle toward the inner circumferential surface in a cross-section along the bearing axis direction of the inner ring. An insulating bearing characterized by the following features.

8. The inclination angle θ3 of the anchor recess formed on the inner circumferential surface is in the range of 20 to 60 degrees toward the center line in the width direction of the inner ring with respect to the perpendicular to the inner circumferential surface in a cross section along the bearing axis direction of the inner ring. The inclination angle θ4 of the anchor recess formed on the end face is in the range of 20 to 60 degrees toward the inner circumferential surface with respect to the perpendicular to the end face in a cross-section along the bearing axis direction of the inner ring. The insulating bearing according to feature 7.

9. The insulating bearing according to any one of claims 1 to 8, characterized in that the depth of the anchor recess is in the range of 20 μm to 100 μm.

10. The insulating bearing according to any one of claims 1 to 8, characterized in that the anchor recesses are provided at intervals of 100 μm to 800 μm.

11. The insulating bearing according to any one of claims 1 to 8, characterized in that the anchor recess is a circumferential groove formed in the circumferential direction.

12. The insulating bearing according to any one of claims 1 to 8, characterized in that the anchor recess is a grid-like groove having a circumferential groove formed in the circumferential direction and grooves intersecting the circumferential groove.

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