Electric corrosion prevention member for rolling bearing and electric corrosion prevention rolling bearing unit

Abstract

To provide an electric corrosion prevention member which inhibits generation of abrasion powder from a conductive member and abrasion powder generated by sliding contact between the conductive member and a mating member, prevents damage of the mating member, and can be used in an existing bearing without forming new processing in the bearing and limiting the type of the bearing, and to provide an electric corrosion prevention rolling bearing unit attached with the electric corrosion prevention member.SOLUTION: An electric corrosion prevention member for a rolling bearing includes: a spring plate comprising an annular part and one or multiple elastic parts which continuously extend from the annular part in a radial form; and soft conductive members each of which is attached to a surface facing a rotary ring at the elastic part. The soft conductive member may contact with a side surface of the rotary ring. An electric corrosion prevention rolling bearing unit includes the electric corrosion prevention member.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrolytic corrosion prevention member for a rolling bearing that is mounted to prevent electrolytic corrosion of a rolling bearing in a rolling bearing unit, and to an electrolytic corrosion prevention rolling bearing unit equipped with the electrolytic corrosion prevention member for a rolling bearing. [Background technology]

[0002] In recent years, electric vehicles in which an electric motor serving as a drive source is disposed inside or near the wheel to drive the wheel are becoming more and more practical. Such drive motors are generally called in-wheel motors. A typical in-wheel motor has a structure in which a stator is fixed to a motor housing, and a rotor is disposed on the inner diameter side of the stator with a radial gap therebetween, making it a so-called inner rotor type motor. In addition, in consideration of the motor's performance and control performance, a brushless DC motor driven by an inverter is often used as the drive method for in-wheel motors.

[0003] In inverter drive systems, a potential difference occurs between the stator and rotor due to parasitic capacitance between them. This potential difference generates a so-called shaft voltage and shaft current, and when this shaft current passes through the rolling bearing that supports the rotor, it causes a phenomenon known as "electrical corrosion," which damages the rolling bearing. Specifically, current flows locally at the contact points between the rolling surfaces of the outer and inner rings of the rolling bearing and the rolling elements, causing the raceway surface or rolling surface to melt and become uneven, which roughens the rolling surfaces and rolling element surfaces of the bearing, causing noise and vibration, and if excessive electrical corrosion occurs, it can also affect the life of the bearing.

[0004] One approach to prevent electrolytic corrosion in rolling bearings is to use conductive materials. For example, Patent Documents 1 and 2 propose a bearing consisting of a contact body for electrical conductivity with the motor rotor, an elastic body for pressing the contact body towards the rotor, and a storage section for accommodating the contact body and the elastic body, with the storage section being provided in the motor housing and electrically conductive with the motor stator via the motor housing.

[0005] Moreover, Patent Document 3 proposes an earthing device in which the tips of broom-shaped conductive fibers are brought into contact with the outer circumferential surface of a rotating shaft.

[0006] Furthermore, Patent Document 4 proposes an electrical corrosion prevention device in which the annular seat that contacts the end face of the outer ring of the bearing is bent into a wave washer shape, and an elastic conductor is used that has a contact piece that extends from the inside of the annular seat and contacts the center of the end face of the rotating shaft, and the annular seat is overlapped with the end face of the outer ring of the bearing fitted into a bearing housing, and the contact piece is abutted against the center of the end face of the rotating shaft fitted into the inner ring of the bearing, and the surface of the annular seat is pressed with the lid-like wall of the bearing housing to establish electrical conductivity.

[0007] Furthermore, Patent Document 5 proposes accommodating a rod-shaped conductive brush in a support hole provided in one of the two raceways, and using an elastic member to urge the tip of the conductive brush toward the other raceway so that it slides against the other raceway, thereby establishing electrical conductivity between the two raceways. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2011-135720 A [Patent Document 2] JP 2011-135722 A [Patent Document 3] JP 2020-127257 A [Patent Document 4] JP 2002-146568 A [Patent Document 5] Japanese Utility Model Application Publication No. 4-8820 Summary of the Invention [Problem to be solved by the invention]

[0009] However, in any of the techniques described in the patent documents, wear powder generated from the conductive member may cause contamination of the lubricating oil or grease composition sealed for lubrication, which may cause damage to the rolling surfaces or rolling contact surfaces.In addition, the wear powder may damage the mating material of the conductive member.

[0010] Specifically, in Patent Documents 1 and 2, the contact body, elastic body, and housing are made of metal members, and metal powder is generated when these slide against each other as the motor vibrates. In addition, the contact body, elastic body, and housing must be provided in the motor housing, which requires space for them.

[0011] In addition, in Patent Document 3, the tip of the broom-shaped conductive fiber is brought into contact with the outer circumferential surface of the rotating shaft, but in order to increase the contact area between the tip of the broom-shaped conductive fiber and the rotating shaft compared to when the tip is simply brought into contact with the rotating shaft, the broom-shaped conductive fiber is brought into contact with the outer circumferential surface of the rotating shaft in a bent state. In other words, the tip of the broom-shaped conductive fiber is in contact with the outer circumferential surface of the rotating shaft with a relatively strong pressing force, so that wear powder is generated. At the same time, the outer circumferential surface of the rotating shaft, which is the mating material of the broom-shaped conductive fiber, is also damaged.

[0012] In Patent Document 4, the elastic conductor and the rotating shaft are both made of metal, and metal powder is generated when they slide in contact with each other. At the same time, the end face of the rotating shaft, which is the mating material of the elastic conductor, is damaged.

[0013] In addition, in Patent Document 5, the tip of the rod-shaped conductive brush is in a biased state in contact with the other raceway, which generates wear powder from the conductive brush. At the same time, the other raceway, which is the mating material of the conductive brush, is also damaged. Furthermore, it is necessary to form a support hole in the raceway to accommodate the conductive brush and the elastic member, which places a large load on the raceway.

[0014] Therefore, the present invention aims to provide an electrolytic corrosion prevention member that is space-saving and inexpensive, which not only suppresses the generation of wear powder from a conductive member or wear powder caused by sliding contact between a conductive member and a mating material, but also suppresses damage to the mating material, does not require new processing on the bearing, and is not limited to the type of bearing, making it compatible with existing bearings, and also provides an electrolytic corrosion prevention rolling bearing unit equipped with the electrolytic corrosion prevention member. [Means for solving the problem]

[0015] The above object of the present invention is achieved by the following configuration [1] relating to an electrolytic corrosion prevention member for a rolling bearing.

[0016] [1] In a rolling bearing unit having a rolling bearing in which one raceway is a fixed race and the other raceway is a rotating race, an electrolytic corrosion prevention member is attached to the rolling bearing unit in order to prevent electrolytic corrosion of the rolling bearing, a spring plate made of a thin plate of a conductive material, the spring plate including a circular ring portion and a plurality of elastic portions extending radially from the circular ring portion; a soft conductive member attached to a surface of the elastic portion facing the rotating wheel; In addition to providing The soft conductive member is capable of abutting against a side surface of the rotating wheel. An electrolytic corrosion prevention member for a rolling bearing, comprising:

[0017] Further, preferred embodiments of the present invention relating to the electrolytic corrosion prevention member for a rolling bearing relate to the following [2] to [6].

[0018] [2] The electrolytic corrosion prevention member for a rolling bearing according to [1], characterized in that the annular portion is pressed against the side surface of the fixed ring via a spacer. [3] The electrolytic corrosion prevention member for a rolling bearing according to [1], characterized in that the soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a nonwoven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body. [4] The electrolytic corrosion prevention member for a rolling bearing according to [2], characterized in that the soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a nonwoven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body. [5] The electrolytic corrosion prevention member for a rolling bearing described in any one of [1] to [4], characterized in that the multiple elastic portions of the spring plate are bent toward the rotating wheel. [6] The electrolytic corrosion prevention member for a rolling bearing described in any one of [1] to [4], characterized in that the multiple elastic portions of the spring plate are formed flush with the annular portion.

[0019] The above object of the present invention can be achieved by the following configuration [7] relating to an electrolytic corrosion prevention member for a rolling bearing. [7] In a rolling bearing unit having a rolling bearing in which one raceway is a fixed race and the other raceway is a rotating race, an electrolytic corrosion prevention member is attached to the rolling bearing unit in order to prevent electrolytic corrosion of the rolling bearing, a spring plate made of a thin plate of a conductive material, the spring plate including a circular ring portion and a plurality of elastic portions extending radially from the circular ring portion; a soft conductive member attached to a surface of the elastic portion facing a rotating member into which the rotating wheel is fitted; In addition to providing The soft conductive member is capable of abutting against a side surface of the rotating member. An electrolytic corrosion prevention member for a rolling bearing, comprising:

[0020] Further, preferred embodiments of the present invention relating to the electrolytic corrosion prevention member for a rolling bearing relate to the following [8] to

[12] .

[0021] [8] The electrolytic corrosion prevention member for a rolling bearing as described in [7], characterized in that the annular portion is pressed against the side surface of the fixed ring via a spacer. [9] The electrolytic corrosion prevention member for a rolling bearing according to [7], characterized in that the soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a nonwoven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body.

[10] The electrolytic corrosion prevention member for a rolling bearing according to [8], characterized in that the soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a nonwoven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body.

[11] The electrolytic corrosion prevention member for a rolling bearing described in any one of [7] to

[10] , characterized in that the multiple elastic portions of the spring plate are bent toward the rotating wheel.

[12] The electrolytic corrosion prevention member for a rolling bearing described in any one of [7] to

[10] , characterized in that the multiple elastic portions of the spring plate are formed flush with the annular portion.

[0022] The above object of the present invention is achieved by the electrolytic corrosion prevention rolling bearing unit having the following configuration

[13] .

[0023]

[13] A rolling bearing having one raceway ring fixed and the other raceway ring rotating, An electrolytic corrosion prevention rolling bearing unit, comprising an electrolytic corrosion prevention member for a rolling bearing according to any one of [1] to

[12] attached thereto.

[0024] In the following description, the "electrolytic corrosion prevention member for a rolling bearing" will be referred to simply as the "electrolytic corrosion prevention member," and the "electrolytic corrosion prevention rolling bearing unit" will be referred to simply as the "bearing unit." Effect of the Invention

[0025] The electrolytic corrosion prevention member of the present invention is a soft conductive member attached to the elastic portion of a spring plate and abutting against the side surface of a rotating wheel or a rotating member. The urging force of the soft conductive member against the side surface of the rotating wheel or the rotating member by the spring plate is not very strong, so wear powder is unlikely to be generated. Moreover, because the soft conductive member is a soft material, damage to the opposing rotating wheel is minimal.

[0026] In addition, the spring plate does not require any processing on the rolling bearing, and there is no restriction on the type of rolling bearing, so it can be applied to existing rolling bearings, making it highly versatile. Furthermore, the spring plate is a thin plate, so it can minimize the increase in space required for the bearing unit to be mounted.

[0027] Since the bearing unit of the present invention is fitted with the electrolytic corrosion prevention member of the present invention, the generation of wear powder and damage to the mating material are suppressed, and furthermore, the bearing unit is highly versatile and does not require an increase in space. [Brief description of the drawings]

[0028] [Figure 1] FIG. 1 shows an example of application of an electrolytic corrosion prevention member according to a first embodiment of the present invention to an inner ring rotating type bearing unit, in which (A) is a plan view, (B) is a cross-sectional view taken along line AA of (A), and (C) is an enlarged view showing the bending portion between the annular portion and the elastic portion in (B). [Diagram 2] FIG. 2 is a cross-sectional view showing an example of a bearing unit equipped with the electrolytic corrosion prevention member shown in FIG. [Diagram 3] FIG. 3 is a diagram showing a state in which the electrolytic corrosion prevention member is pressed against the outer ring by a pressing member in FIG. [Figure 4] FIG. 4 shows an example of application of an electrolytic corrosion prevention member according to the second embodiment of the present invention to a bearing unit on the outer ring rotation side, where (A) is a plan view and (B) is a cross-sectional view taken along line AA of (A). [Diagram 5] FIG. 5 is a cross-sectional view showing an example of a bearing unit equipped with the electrolytic corrosion prevention member shown in FIG. [Figure 6]FIG. 6 is a diagram showing a state in which the electrolytic corrosion prevention member is pressed against the inner ring by a pressing member in FIG. [Figure 7] FIG. 7 is a cross-sectional view showing an example of an inner ring rotating type bearing unit equipped with an electrolytic corrosion prevention member according to a third embodiment of the present invention. [Figure 8] FIG. 8 is a cross-sectional view showing an example of an inner ring rotating type bearing unit equipped with another electrolytic corrosion prevention member according to the third embodiment of the present invention. [Figure 9] FIG. 9 is a cross-sectional view showing an example of an outer ring rotating type bearing unit equipped with an electrolytic corrosion prevention member according to a fourth embodiment of the present invention. [Figure 10] FIG. 10 is a cross-sectional view showing an example of an outer ring rotating type bearing unit equipped with another electrolytic corrosion prevention member according to the fourth embodiment of the present invention. [Figure 11] FIG. 11 is a cross-sectional view corresponding to FIG. 1(B) of an electrolytic corrosion prevention member according to a modified example of the present invention. [Figure 12] FIG. 12 is a cross-sectional view showing an example of a bearing unit to which the electrolytic corrosion prevention member shown in FIG. 11 is attached. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments described below, and can be modified and implemented as desired without departing from the gist of the present invention.

[0030] (First embodiment: Electrical corrosion prevention member for inner ring rotation and bearing unit) Fig. 1 shows an example of an electrolytic corrosion prevention member of the present invention that is applied when the rotating ring is an inner ring, Fig. 1(A) is a plan view thereof, Fig. 1(B) is a cross-sectional view taken along line AA in Fig. 1(A), and Fig. 1(C) is an enlarged view showing the bending portion between the annular portion and the elastic portion in Fig. 1(B). Fig. 2 is a cross-sectional view showing an example of a bearing unit of the present invention, to which the electrolytic corrosion prevention member shown in Fig. 1 is attached.

[0031] As shown in Fig. 1, the electrolytic corrosion prevention member 1A for inner ring rotation includes a spring plate 10A composed of an annular portion 11A and a plurality of elastic portions 13A that are bent at an inner diameter side end portion 12A of the annular portion 11A and extend radially toward the center of the annular portion 11A. As shown in Fig. 2, the elastic portions 13A are bent toward the right side in the figure so as to face the inner ring 52 of the rolling bearing 50 when mounted on the bearing unit 100A. In addition, notches 15A are formed on both sides of the bent portion of the elastic portions 13A with the annular portion 11A to maintain the bent state of the elastic portions 13A.

[0032] The spring plate 10A is made entirely of a thin plate made of a conductive material such as metal. When the conductive material is a metal, stainless steel is preferred because it is easy to process and is less prone to rust.

[0033] A soft conductive member 20 is attached to the surface of each elastic portion 13A facing the inner ring 52 of the rolling bearing 50, and the spring plate 10A and the soft conductive member 20 constitute the electrolytic corrosion prevention member 1A. The soft conductive member 20 is attached to the elastic portion 13A using an adhesive.

[0034] The soft conductive member 20 is a soft base material having a conductive material mixed therein or supported thereon. The soft base material may be a porous body such as paper, cloth, or nonwoven fabric, or a resin sheet, and the conductive material may be metal fibers, crushed materials, or powders such as silver, copper, gold, aluminum, or stainless steel, or conductive carbon fibers, crushed materials, or powders. The soft conductive member may be a commercially available product called a "conductive sheet." Among these, it is preferable that the soft conductive member is composed of at least one selected from resin-impregnated nonwoven fabric, resin-impregnated nonwoven fabric, resin-impregnated woven fabric, resin-impregnated soft porous body such as woven fabric or sponge, and soft porous body such as sponge.

[0035] 1(C), the bending angle θ between the annular portion 11A and the elastic portion 13A is appropriately set according to the length (L) of the elastic portion 13A and the size of the soft conductive member 20 so that the soft conductive member 20 abuts against the side surface 52a of the inner ring 52 of the rolling bearing 50 when mounted on the bearing unit 100A. The bending angle θ can also adjust the biasing force of the soft conductive member 20 against the side surface 52a of the inner ring 52 of the rolling bearing 50; the biasing force can be increased by decreasing the bending angle θ, and conversely, the biasing force can be decreased by increasing the bending angle θ.

[0036] There is no limitation on the planar shape of the soft conductive member 20, and it may be a rectangle other than the sector shape shown in Fig. 1(A) or may be a number of small pieces.

[0037] As shown in Fig. 2, a bearing unit 100A is constructed by mounting the electrolytic corrosion prevention member 1A shown in Fig. 1 on a rolling bearing 50, but there is no limitation on the rolling bearing 50, and a plurality of rolling elements (balls) 53 are held by a cage 54 between an outer ring 51 and an inner ring 52 so that they can roll freely, and are lubricated by a lubricating oil or a grease composition. Here, the rotating ring is the inner ring 52, and a shaft 60 directly connected to a motor (not shown) is fitted into the inner ring 52. The outer ring 51 is a fixed ring, and is fixed to a housing 70.

[0038] 3, in this embodiment, the annular portion 11A of the electrolytic corrosion prevention member 1A is pressed against the side surface of the outer ring 51 by the conductive pressing member 80 via the conductive spacer 30. The thickness of the spacer 30 may be determined taking into consideration the pressing amount of the spring plate 10A and the thickness of the soft conductive member 20. The annular portion 11A of the electrolytic corrosion prevention member 1A may directly abut against the side surface of the outer ring 51 without providing the spacer 30.

[0039] In such an inner ring rotating type bearing unit 100A, normally, current from the motor flows through the shaft 60 to the inner ring 52, and current flows inside the bearing to the rolling elements 53 and the outer ring 51, causing electrolytic corrosion in the rolling bearing 50. Therefore, in the present invention, the electrolytic corrosion prevention member 1A is mounted on the housing 70 so that the soft conductive member 20 abuts against the side surface 52a of the inner ring 52. Also, the annular portion 11A of the spring plate 10A is in electrical contact with the side surface of the outer ring 51 via the conductive spacer 30, and is also in electrical contact with the conductive pressing member 80.

[0040] As a result, current from the shaft 60 flows through the soft conductive member 20 via the inner ring 52 to the elastic portion 13A and the annular portion 11A of the spring plate 10A, and then through the outer peripheral end face 14A of the annular portion 11A, the pressing member 80, the spacer 30 and the outer ring 51 to the housing 70, so that no current flows inside the bearing and the rolling bearing 50 does not suffer from electrical corrosion. Since the outer ring 51 has a large contact area with the housing 70 , the current that flows through the outer ring 51 does not pass through the rolling elements 53 but flows to the housing 70 . In this embodiment, the outer peripheral end surface 14A of the annular portion 11A and the spacer 30 contact the housing 70, but they may be sandwiched between the outer ring 51 and the pressing member 80 without contacting the housing 70. In that case, the current flowing through the annular portion 11A flows to the housing 70 via the outer ring 51 and the pressing member 80. Furthermore, the annular portion 11A of the electrolytic corrosion prevention member 1A may be pressed directly against the side surface of the outer ring 51 via the conductive spacer 30, without providing the pressing member 80, and may be fixed in contact with the housing .

[0041] In addition, since the side surface 52a of the inner ring 52 is in contact with the soft conductive member 20, the side surface 52a of the inner ring 52 is not damaged, and a decrease in the rotational torque of the inner ring 52 can be suppressed. Moreover, since the base material of the soft conductive member 20 is a porous body that has oil absorption and oil retention properties, oil is easily discharged between adjacent spring plates 10A when the shaft rotates, and an oil film is unlikely to form, so the conductivity is good even when used in oil. Furthermore, by making the base material of the soft conductive member 20 a porous body, the friction coefficient is reduced even when used in environments other than oil, and a decrease in the rotational torque of the inner ring 52 can be suppressed.

[0042] Furthermore, the spring plate 10A of the electrolytic corrosion prevention member 1A is a thin plate, which can minimize the increase in space required for the bearing unit 100A. Also, since there are no restrictions on the rolling bearing 50 and no processing is required, the member can be applied to existing rolling bearings, making it highly versatile.

[0043] By increasing the contact area between the soft conductive member 20 of the electrolytic corrosion prevention member 1A and the side surface 52a of the inner ring 52 of the rolling bearing 50, electrolytic corrosion of the rolling bearing 50 can be more effectively prevented. Since the spring plate 10A is an elastic member made of a curved thin plate as a whole, by pressing the annular portion 11A of the electrolytic corrosion prevention member 1A against the outer ring 51, the elastic force caused by the pressing acts on the elastic portion 13A, which is pushed and spread so that the bending angle θ shown in FIG. 1(C) increases, and the entire elastic portion 13A moves toward the rolling bearing 50. Accordingly, the portion of the soft conductive member 20 that was away from the side surface 52a of the inner ring 52 in FIG. 2 also moves toward the rolling bearing 50, and almost the entire soft conductive member 20 comes into contact with the side surface 52a of the inner ring 52.

[0044] (Second embodiment: Electrical corrosion prevention member for outer ring rotation and bearing unit) In the above, the case where the inner ring 52 of the rolling bearing 50 is the rotating ring has been described, but the outer ring 51 may be the rotating ring. Fig. 4 shows an electrolytic corrosion prevention member for outer ring rotation, Fig. 4(A) is its plan view, and Fig. 4(B) is a cross-sectional view taken along line AA in Fig. 4(A). Fig. 5 shows a bearing unit equipped with the electrolytic corrosion prevention member shown in Fig. 4.

[0045] As shown in Fig. 4, the electrical corrosion prevention member 1B for outer ring rotation includes a spring plate 10B composed of an annular portion 11B and a plurality of elastic portions 13B that are bent at an outer diameter side end portion 12B of the annular portion 11B and extend radially from the center of the annular portion 11B toward the outer periphery. As shown in Fig. 5, the elastic portions 13B are bent toward the right side in the drawing so as to face the outer ring 51 of the rolling bearing 50 when mounted on the bearing unit 100B. In addition, arc-shaped notches 15B are formed on both sides of the bent portion of the elastic portions 13B with the annular portion 11B.

[0046] A soft conductive member 20 is attached to the surface of each elastic portion 13B facing the outer ring 51 of the rolling bearing 50, and the spring plate 10B and the soft conductive member 20 constitute the electrolytic corrosion prevention member 1B. The soft conductive member 20 is similar to the electrolytic corrosion prevention member 1A described above, and a description thereof will be omitted.

[0047] 5, the rolling bearing 50 has an inner ring 52 fixed to a fixed member 75, and a rotating member 65 attached to an outer ring 51. The electrolytic corrosion prevention member 1B is attached to the fixed member 75 with the soft conductive member 20 in contact with the side surface 51a of the outer ring 51.

[0048] Although current flows from a motor (not shown) that drives the rotating member 65 to the outer ring 51, it flows from the soft conductive member 20 through the outer ring 51 to the elastic portion 13B and the annular portion 11B of the spring plate 10B, and then through the inner end face 14B of the annular portion 11B, the pressing member 80, the spacer 30 and the inner ring 52 to the fixed member 75. As a result, no current flows inside the bearing, and the rolling bearing 50 does not suffer from electrolytic corrosion.

[0049] Furthermore, as shown in FIG. 6, the pressing member 80 presses the annular portion 11B of the electrolytic corrosion prevention member 1B against the inner ring 52, thereby increasing the contact area between the soft conductive member 20 and the side surface 51a of the outer ring 51, thereby making it possible to more effectively prevent electrolytic corrosion of the rolling bearing 50.

[0050] In this embodiment as well, the annular portion 11B of the electrolytic corrosion prevention member 1B may directly contact the side surface of the inner ring 52 without providing the spacer 30. In addition, the inner end surface 14B of the annular portion 11B and the spacer 30 may abut against the fixing member 75, or may not abut against the fixing member 75 and be clamped between the fixing member 75 and the inner ring 52 by the pressing member 80.

[0051] (Third embodiment: Electrical corrosion prevention member for inner ring rotation and bearing unit) 7 shows a case where the electrolytic corrosion prevention member is mounted on a bearing unit in which the rotating ring is an inner ring, as in the first embodiment. In this case, a step surface 60c having a smaller diameter than a fitting surface 60b on which the inner ring 52 fits is formed on a shaft 60 which is a rotating member on which the inner ring 52 fits.

[0052] The soft conductive member 20 of the spring plate 10A is attached to a surface of the elastic portion 13A that faces the shaft 60 in the axial direction, specifically, to a side surface 60a between a fitting surface 60b with which the inner ring 52 fits and a step surface 60c, by elastically deforming the elastic portion 13A. Therefore, the soft conductive member 20 can abut against the side surface 60a of the shaft 60.

[0053] In this type of inner ring rotating type bearing unit 100A, the soft conductive member 20 of the electrolytic corrosion prevention member 1A is attached to the housing 70 so as to abut against the side surface 60a of the shaft 60. The annular portion 11A of the spring plate 10A is in electrical contact with the side surface of the outer ring 51 via the conductive spacer 30, and is also in electrical contact with the end face of the flange portion 71 of the housing 70.

[0054] As a result, the current from the shaft 60 flows from the soft conductive member 20 through the side surface 60a of the shaft 60 to the elastic portion 13A and the annular portion 11A of the spring plate 10A, and then through the outer peripheral end face 14A of the annular portion 11A, the spacer 30 and the outer ring 51 to the housing 70, or directly to the housing 70, so that no current flows inside the bearing and the rolling bearing 50 does not suffer from electrolytic corrosion.

[0055] In this embodiment, unlike the first embodiment, the electrolytic corrosion prevention member 1A does not come into contact with the side surface 52a of the inner ring 52, and therefore the design freedom of the rolling bearing, such as the attachment of a snap ring, can be improved. In addition, in this embodiment, the electrolytic corrosion prevention member and the rolling bearing are positioned separately, so it is also possible to control the respective lubrication environments separately. For example, it is possible to make only the electrolytic corrosion prevention member into a dry environment, or to increase or decrease the amount of oil lubrication between the electrolytic corrosion prevention member and the rolling bearing.

[0056] In particular, in the bearing unit 100A shown in FIG. 7, the position where the soft conductive member 20 contacts the side surface 60a of the shaft 60 has a smaller diameter than the position where the soft conductive member 20 contacts the side surface 52a of the inner ring 52 as shown in FIG. 1, so that the circumferential speed of the side surface 60a of the shaft 60 can be reduced, and the generation of wear powder and drag loss can be further suppressed.

[0057] As shown in FIG. 8, in this embodiment, a flange portion 62 that protrudes radially outward from a fitting surface 60b may be provided on the shaft 60, and the soft conductive member 20 may be in contact with a side surface 60a of the flange portion 62.

[0058] (Fourth embodiment: Electrical corrosion prevention member for outer ring rotation and bearing unit) 9 shows a case where the electrolytic corrosion prevention member is mounted on a bearing unit in which the rotating ring is an outer ring, as in the second embodiment. In this case, a step surface 65c having a larger diameter than a fitting surface 65b on which the outer ring 51 fits is formed on a rotating member 65 on which the outer ring 51 fits.

[0059] The soft conductive member 20 of the spring plate 10B is attached to a surface of the elastic portion 13B that faces the rotating member 65 in the axial direction, specifically, to a side surface 65a between a fitting surface 65b with which the outer ring 51 fits and a step surface 65c, by elastically deforming the elastic portion 13B. Therefore, the soft conductive member 20 can abut against the side surface 65a of the rotating member 65.

[0060] In this outer ring rotating type bearing unit 100B, the soft conductive member 20 of the electrolytic corrosion prevention member 1B is attached to the rotating member 65 so as to abut against a side surface 65a of the rotating member 65. The annular portion 11B of the spring plate 10B is in electrical contact with the side surface of the inner ring 52 via the conductive spacer 30, and is also in electrical contact with the end face of the flange portion 76 of the fixed member 75.

[0061] As a result, current from a motor (not shown) that drives the rotating member 65 flows from the soft conductive member 20 through the side surface 65a of the rotating member 65 to the elastic portion 13B and the annular portion 11B of the spring plate 10B, and then through the inner end face 14B of the annular portion 11B, the spacer 30 and the inner ring 52 to the fixed member 75, or directly to the fixed member 75, so that no current flows inside the bearing and the rolling bearing 50 does not suffer from electrical corrosion.

[0062] In this embodiment, unlike the second embodiment, the electrolytic corrosion prevention member 1B does not come into contact with the side surface 51a of the outer ring 51, and therefore the freedom in designing the rolling bearing, such as the attachment of a snap ring, can be improved. In addition, in this embodiment, the electrolytic corrosion prevention member and the rolling bearing are positioned separately, so it is also possible to separately control the lubrication environments for each. For example, it is possible to make only the electrolytic corrosion prevention member into a dry environment, or to increase or decrease the amount of oil lubrication between the electrolytic corrosion prevention member and the rolling bearing.

[0063] In this embodiment, as shown in FIG. 10, a flange portion 67 protruding from a fitting surface 65b to the inner diameter side may be provided on a rotating member 65, and the soft conductive member 20 may be made to abut against a side surface 65a of this flange portion 67.

[0064] In particular, in the bearing unit 100B shown in Figure 10, the position where the soft conductive member 20 contacts the side surface 65a of the rotating member 65 has a smaller diameter than the position where it contacts the side surface 51a of the outer ring 51 as shown in Figure 6, so that the circumferential speed of the side surface 65a of the rotating member 65 can be reduced, and the generation of wear powder and drag loss can be further suppressed.

[0065] The present invention is not limited to the above-described embodiment, and can be modified and improved as appropriate. For example, in the above embodiment, the multiple elastic portions 13A, 13B of the spring plates 10A, 10B are configured to be bent toward the rotating ring, but they may be configured to be formed flush with the annular portions 11A, 11B without being bent at the inner diameter side end 12A and the outer diameter side end 12B. As shown in Fig. 11, for example, in the case of an electrolytic corrosion prevention member 1A for inner ring rotation, the annular portion 11A and the elastic portion 13A are continuous in a straight line in a side view.

[0066] 12, when the annular portion 11A of the electrolytic corrosion prevention member 1A is clamped between the flange portion 71 of the housing 70 and the side surface of the outer ring 51, the elastic portion 13A of the electrolytic corrosion prevention member 1A elastically deforms by an amount equivalent to the thickness of the soft conductive member 20, and the bending reaction force of the spring plate 10A brings the soft conductive member 20 into contact with the side surface of the inner ring 52. This allows the bearing unit 100A to achieve the same function as the above embodiment.

[0067] In this case, since bending of the spring plate 10A is not necessary, the electrolytic corrosion prevention member 1A can be manufactured at low cost, and the spring plate 10A and the soft conductive member 20 can be bonded to each other easily.

[0068] In addition, in this embodiment, the spring plate is configured to have multiple elastic portions extending radially toward the center of the annular portion, but it may also be configured to have a single elastic portion extending toward the center of the annular portion. [Explanation of symbols]

[0069] 1A, 1B Electrolytic corrosion prevention materials 10A, 10B Spring plate 11A, 11B Circular ring 12A Inner diameter end 12B Outer diameter end 13A, 13B Elastic part 14A Outer periphery 14B Inner periphery end face 15A, 15B Notch 20 Soft conductive material 30 Spacer 50 Bearings 51 Outer ring 51a,52a side 52 Inner Circle 53 Rolling elements 54 Cage 60 Shaft 65 Rotating parts 70 Housing 75 Fixing member 80 Holding member 100A, 100B Bearing unit

Claims

1. In a rolling bearing unit including a rolling bearing having one raceway ring being a fixed raceway and the other raceway ring being a rotating raceway, an electrolytic corrosion prevention member is attached to the rolling bearing unit in order to prevent electrolytic corrosion of the rolling bearing, a spring plate made of a thin plate of a conductive material, the spring plate including a circular ring portion and a plurality of elastic portions extending radially from the circular ring portion; a soft conductive member attached to a surface of the elastic portion facing the rotating wheel; In addition to providing The soft conductive member is capable of abutting against a side surface of the rotating wheel. An electrolytic corrosion prevention member for a rolling bearing, comprising:

2. 2. The electrolytic corrosion prevention member for a rolling bearing according to claim 1, wherein the annular portion is pressed against a side surface of the fixed ring via a spacer.

3. 2. The electrolytic corrosion prevention member for a rolling bearing as described in claim 1, characterized in that the soft conductive member is composed of at least one selected from the group consisting of resin-impregnated nonwoven fabric, nonwoven fabric, resin-impregnated woven fabric, woven fabric, resin-impregnated soft porous body, and soft porous body.

4. 3. The electrolytic corrosion prevention member for a rolling bearing as described in claim 2, characterized in that the soft conductive member is composed of at least one selected from the group consisting of a resin-impregnated nonwoven fabric, a nonwoven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body.

5. 2. The electrolytic corrosion prevention member for a rolling bearing according to claim 1, wherein the elastic portions of the spring plate are bent toward the rotating wheel.

6. 2. The electrolytic corrosion prevention member for a rolling bearing according to claim 1, wherein the elastic portions of the spring plate are formed flush with the annular portion.

7. In a rolling bearing unit including a rolling bearing having one raceway ring being a fixed raceway and the other raceway ring being a rotating raceway, an electrolytic corrosion prevention member is attached to the rolling bearing unit in order to prevent electrolytic corrosion of the rolling bearing, a spring plate made of a thin plate of a conductive material, the spring plate including a circular ring portion and a plurality of elastic portions extending radially from the circular ring portion; a soft conductive member attached to a surface of the elastic portion facing a rotating member into which the rotating wheel is fitted; In addition to providing The soft conductive member is capable of abutting against a side surface of the rotating member. An electrolytic corrosion prevention member for a rolling bearing, comprising:

8. 8. The electrolytic corrosion prevention member for a rolling bearing according to claim 7, wherein the annular portion is pressed against a side surface of the fixed ring via a spacer.

9. The electrolytic corrosion prevention member for a rolling bearing as described in claim 7, characterized in that the soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a nonwoven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body.

10. The electrolytic corrosion prevention member for a rolling bearing as described in claim 8, characterized in that the soft conductive member is composed of at least one selected from the group consisting of a resin-impregnated nonwoven fabric, a nonwoven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body.

11. 8. The electrolytic corrosion prevention member for a rolling bearing according to claim 7, wherein the elastic portions of the spring plate are bent toward the rotating ring.

12. 8. The electrolytic corrosion prevention member for a rolling bearing according to claim 7, wherein the elastic portions of the spring plate are formed flush with the annular portion.

13. A rolling bearing is provided in which one raceway is a fixed raceway and the other raceway is a rotating raceway, An electrolytic corrosion prevention rolling bearing unit, comprising an electrolytic corrosion prevention member for a rolling bearing according to any one of claims 1 to 12 attached thereto.

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