Electromagnetic noise suppression member for rolling bearings and rolling bearing unit

Abstract

The present invention provides an electromagnetic noise suppression member that suppresses the generation of wear particles from conductive members or wear particles resulting from the sliding contact between conductive members and mating materials, as well as suppresses damage to the mating material, and can be used with existing bearings without forming new processing on the bearing or being limited by the type of bearing, and a rolling bearing unit equipped with the electromagnetic noise suppression member. [Solution] The electromagnetic noise suppression member for the rolling bearing comprises a spring plate composed of an annular portion and one or more elastic portions extending radially from the annular portion, and a soft conductive member mounted on the surface of the elastic portion facing the rotating wheel, wherein the soft conductive member can contact the side surface of the rotating wheel. Furthermore, the rolling bearing unit is equipped with the electromagnetic noise suppression member.

Description

Technical Field

[0005]

[0001] The present invention relates to a rolling bearing electromagnetic noise suppression member mounted to suppress the generation of electromagnetic noise in a rolling bearing unit, and a rolling bearing unit equipped with the rolling bearing electromagnetic noise suppression member.

Background Art

[0002] In recent years, the practical application of electric vehicles that drive wheels by arranging an electric motor as a drive source inside or near the wheels has been progressing. In such electronic products in drive motors and the like, electromagnetic noise caused by induced current, discharge, interruption, etc. from the electronic products and electric components may occur, and problems such as electromagnetic interference between components may occur. Therefore, various devices for suppressing the generation of electromagnetic noise have been proposed. For example, in Patent Document 1, a conductive bearing is proposed in which a rod-shaped carbon brush having conductivity is arranged between a metal ring arranged adjacent to an outer ring and an inner ring. Since the carbon brush is biased toward the inner ring by a spring and its tip slides on the inner ring, the current flowing through the conductive bearing can be made to flow out of the system through the metal ring and the brush, making it possible to remove electromagnetic noise.

[0003] In Patent Document 2, a conductive device is proposed that can escape electromagnetic noise by suppressing the generation of an oil film formed between a conductive rubber lip mounted on a rotating shaft and a metal housing by centrifugal force or controlling the oil film thickness. By suppressing the generation of the oil film or making the oil film thickness thinner, the electrical resistance of the oil film is reduced, making it possible to escape electromagnetic noise from the rotating shaft to the housing.

[0004] In Patent Document 3, a rolling bearing is proposed that includes a rigid rolling element and a flexible rolling element having conductivity, and the raceway surface of the flexible rolling element is rougher than the raceway surface of the rolling element. Patent Document 3 describes that it is possible to operate in a state where the oil film on the raceway surface of the flexible rolling element is cut, and the electromagnetic noise prevention effect can be improved.

[0005] Patent Document 4 proposes an electromagnetic noise suppression device that electrically connects the metal case of the electric motor and the rotating shaft inside the electric motor using conductive means such as a sliding contact member, thereby diverting electromagnetic noise induced on the rotating shaft to a metal electric motor housing grounded to the vehicle body. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2024-130948 [Patent Document 2] Japanese Patent Publication No. 2023-018214 [Patent Document 3] Japanese Patent Publication No. 2022-139252 [Patent Document 4] Japanese Patent Publication No. 2000-244180 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, in Patent Document 1, frictional heat may be generated during use due to sliding contact between the conductive member and the mating material, which reduces the durability of the bearing. Furthermore, with the recent improvement in motor performance, the peripheral speed of the rotating members has also increased, so further suppression of temperature rise is required. Moreover, in Patent Document 1, in order to combine the outer ring and the metal ring so that they are movable and relatively rotatable in the width direction and axial direction, it is necessary to form an inner claw on the outer ring and an outer claw on the metal ring.

[0008] Furthermore, in the technology described in Patent Document 2, wear particles generated from the metal housing and mating material may contaminate the lubricant or grease sealed inside for lubrication, potentially causing damage to the rolling surface. Moreover, in Patent Document 2, it is necessary to form a shaft hole in the housing to allow the lip to slide against the rotating shaft when it is subjected to centrifugal force as it rotates, for the purpose of sealing the housing so that the lubricating oil that lubricates the motor does not leak out to the outside.

[0009] Furthermore, in the technology described in Patent Document 3, in order to remove the oil film on the raceway surface of the flexible rolling element, mirror polishing is not performed after cutting, and it is necessary to perform matte finishing or blast finishing. Thus, in the inventions described in Patent Documents 1 to 3 mentioned above, new processing is required for each component.

[0010] Furthermore, while Patent Document 4 selects a wear-resistant material as the sliding contact member, its effect in reducing wear is not sufficient.

[0011] Therefore, the present invention aims to provide an electromagnetic noise suppression member and a rolling bearing unit equipped with the electromagnetic noise suppression member, which have a space-saving and inexpensive configuration, suppress the generation of wear particles from a conductive member or wear particles associated with the sliding contact between a conductive member and a mating material, as well as suppress damage to the mating material, and which do not require any new processing to be formed on the bearing and are compatible with existing bearings without restrictions on the type of bearing. [Means for solving the problem]

[0012] The above objective of the present invention is achieved by the following configurations [1] to

[13] relating to the electromagnetic noise suppression member for rolling bearings.

[0013] [1] An electromagnetic noise suppression member to be mounted on a rolling bearing unit having a rolling bearing in which one raceway is a fixed wheel and the other raceway is a rotating wheel, A spring plate made of a thin sheet of conductive material is composed of an annular portion and at least one elastic portion that extends radially continuously from the annular portion, In the elastic portion, a soft conductive member is mounted on the surface facing the rotating wheel or the rotating member into which the rotating wheel is fitted, Equipped with, The soft conductive member is capable of contacting at least a portion of the surface of the rotating wheel, or at least a portion of the surface of the rotating member. An electromagnetic noise suppression member for rolling bearings, characterized by the above.

[0014] [2] The rolling shaft electromagnetic noise suppression member according to [1], wherein the soft conductive member is composed of at least one selected from a resin-impregnated non-woven fabric, a non-woven fabric, a resin-impregnated woven fabric, a woven fabric, a resin-impregnated soft porous body, and a soft porous body.

[0015] [3] The spring plate is composed of the annular portion and a plurality of elastic portions continuously extending radially from the annular portion. The soft conductive member is mounted on a surface of the elastic portion facing the rotating wheel. The soft conductive member can abut against a side surface of the rotating wheel. The rolling shaft electromagnetic noise suppression member according to [1] or [2], characterized in that.

[0016] [4] The spring plate is composed of the annular portion and a plurality of elastic portions continuously extending radially from the annular portion. The soft conductive member is mounted on a surface of the elastic portion facing the rotating member. The soft conductive member can abut against a side surface of the rotating member. The rolling shaft electromagnetic noise suppression member according to [1] or [2], characterized in that.

[0017] [5] The rolling shaft electromagnetic noise suppression member according to any one of [1] to [4], wherein the annular portion is pressed against a side surface of the fixed wheel with a spacer interposed therebetween.

[0018] [6] The spring plate is composed of the annular portion and a plurality of elastic portions continuously extending radially from the annular portion. The rolling shaft electromagnetic noise suppression member according to any one of [1] to [3] and [5], wherein the plurality of elastic portions are bent toward the side of the rotating wheel.

[0019] [7] The spring plate is composed of the annular portion and a plurality of elastic portions continuously extending radially from the annular portion. The plurality of elastic parts are formed flush with the annular part, and the rolling bearing electromagnetic noise suppression member according to any one of [1] to [5].

[0020] [8] A rolling bearing is provided, in which one raceway ring is a fixed ring and the other raceway ring is a rotating ring, and A rolling bearing unit, characterized in that the rolling bearing electromagnetic noise suppression member according to any one of [1] to [7] is mounted.

[0021] [9] The rolling bearing is an inner ring rotating type in which the fixed ring is an outer ring fixed to the housing, and the rotating ring is an inner ring into which a shaft directly connected to the motor is inserted. The spring plate is composed of the annular part and the elastic part that continuously extends from the inner peripheral side end of the annular part to the center of the annular part. The soft conductive member is mounted on the surface of the elastic part on the side facing the rolling bearing. The soft conductive member can abut against the side surface of the shaft. The rolling bearing electromagnetic noise suppression member according to [1], characterized in that.

[0022]

[10] The rolling bearing electromagnetic noise suppression member according to [9], characterized in that the annular part is pressed against the side surface of the outer ring with a spacer interposed therebetween.

[0023]

[11] The rolling bearing electromagnetic noise suppression member according to [9] or

[10] , characterized in that the elastic part of the spring plate is bent toward the side surface of the shaft.

[0024]

[12] The rolling bearing electromagnetic noise suppression member according to [9] or

[10] , characterized in that the elastic part of the spring plate is formed flush with the annular part.

[0025]

[13] The rolling bearing has an inner ring that rotates, with the outer ring fixed to the housing and the inner ring into which a shaft directly connected to the motor is fitted, A rolling bearing unit characterized by being equipped with an electromagnetic noise suppression member for rolling bearings described in any one of [9] to

[12] . [Effects of the Invention]

[0026] The electromagnetic noise suppression member of the present invention consists of a soft conductive member attached to the elastic portion of a spring plate, which is in contact with at least a portion of the surface of a rotating wheel or rotating member. The biasing force exerted by the spring plate on the soft conductive member against the rotating wheel or rotating member is not very strong, and wear particles are less likely to be generated. Furthermore, because the soft conductive member is made of a soft material, damage to the mating material, the rotating wheel, is also minimized.

[0027] Furthermore, it is highly versatile as it requires no processing of the rolling bearing, has no restrictions on the type of rolling bearing, and can be applied to existing rolling bearings. In addition, the spring plate is thin, which minimizes the increase in space required for the bearing unit it is installed in.

[0028] Since the bearing unit of the present invention is equipped with the electromagnetic noise suppression member of the present invention, the generation of wear particles and damage to the mating material are suppressed, and furthermore, it is highly versatile and does not increase the space required. [Brief explanation of the drawing]

[0029] [Figure 1] Figure 1 shows an example of an electromagnetic noise suppression member according to the first embodiment of the present invention, applied to an inner ring rotating type bearing unit. Figure (A) is a plan view thereof, Figure (B) is a cross-sectional view of (A) AA, and Figure (C) is an enlarged view showing the bent portion between the annular portion and the elastic portion in Figure (B). [Figure 2] Figure 2 is a cross-sectional view showing the electromagnetic noise suppression member shown in Figure 1 being attached to the bearing unit. [Figure 3] Figure 3 is a cross-sectional view showing an example of a bearing unit incorporating the electromagnetic noise suppression member shown in Figure 1. [Figure 4] Figure 4 shows an example of an electromagnetic noise suppression member according to a second embodiment of the present invention, applied to a bearing unit on the outer ring rotation side. Figure (A) is a plan view thereof, and Figure (B) is a cross-sectional view of (A) AA. [Figure 5] Figure 5 is a cross-sectional view showing the electromagnetic noise suppression member shown in Figure 4 being attached to the bearing unit. [Figure 6] Figure 6 is a cross-sectional view showing an example of a bearing unit incorporating the electromagnetic noise suppression member shown in Figure 4. [Figure 7] Figure 7 is a cross-sectional view showing an example of an inner ring rotating type bearing unit equipped with an electromagnetic noise suppression member according to the third embodiment of the present invention. [Figure 8] Figure 8 is a cross-sectional view showing an example of an inner ring rotating type bearing unit equipped with another electromagnetic noise suppression member according to the third embodiment of the present invention. [Figure 9] Figure 9 is a cross-sectional view showing an example of an outer ring rotating type bearing unit equipped with an electromagnetic noise suppression member according to the fourth embodiment of the present invention. [Figure 10] Figure 10 is a cross-sectional view showing an example of an outer ring rotating type bearing unit equipped with another electromagnetic noise suppression member according to the fourth embodiment of the present invention. [Figure 11] Figure 11 shows an example of an electromagnetic noise suppression member according to the fifth embodiment of the present invention, where Figure (A) is a plan view thereof, Figure (B) is a cross-sectional view of Figure (A) AA, and Figure (C) is an enlarged view showing the bent portion of the elastic part in Figure (B). [Figure 12] Figure 12 is a cross-sectional view showing the electromagnetic noise suppression member shown in Figure 11 being attached to the bearing unit. [Figure 13] Figure 13 is a cross-sectional view showing an example of a bearing unit incorporating the electromagnetic noise suppression member shown in Figure 11. [Figure 14] Figure 14 is a cross-sectional view of an electromagnetic noise suppression member according to a modified example of the present invention, corresponding to Figure 1(B). [Figure 15]Figure 15 is a cross-sectional view of an electromagnetic noise suppression member according to a modified example of the present invention, corresponding to Figure 4(B). [Figure 16] Figure 16 is a cross-sectional view of an electromagnetic noise suppression member according to a modified example of the present invention, corresponding to Figure 11(B). [Figure 17] Figure 17 is a cross-sectional view showing an example of a bearing unit equipped with the electromagnetic noise suppression member shown in Figure 14. [Figure 18] Figure 18 is a cross-sectional view showing an example of a bearing unit equipped with the electromagnetic noise suppression member shown in Figure 15. [Figure 19] Figure 19 is a cross-sectional view showing an example of a bearing unit equipped with the electromagnetic noise suppression member shown in Figure 16. [Modes for carrying out the invention]

[0030] Embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to the embodiments described below, and can be modified and implemented as desired without departing from the spirit of the invention. Hereafter, "electromagnetic noise suppression member for rolling bearings" will be simply referred to as "electromagnetic noise suppression member," and "rolling bearing unit" will be simply referred to as "bearing unit."

[0031] (First embodiment: Electromagnetic noise suppression member and bearing unit for inner ring rotation) Figure 1 shows an example of an electromagnetic noise suppression member of the present invention, applicable when the rotating ring is an inner ring. Figure (A) is a plan view thereof, Figure (B) is a cross-sectional view of AA in Figure (A), and Figure (C) is an enlarged view showing the bent portion between the annular portion and the elastic portion in Figure (B). Figure 2 is a cross-sectional view showing how the electromagnetic noise suppression member shown in Figure 1 is mounted on a bearing unit. Figure 3 is a cross-sectional view showing an example of a bearing unit incorporating the electromagnetic noise suppression member shown in Figure 1.

[0032] As shown in Figure 1, the electromagnetic noise suppression member 1A for inner ring rotation comprises a spring plate 10A composed of an annular portion 11A and a plurality of elastic portions 13A that are bent at the inner diameter end 12A of the annular portion 11A and extend radially from the annular portion 11A toward the radial center. Notches 16A are formed on both sides of the bent portion of the elastic portion 13A toward the annular portion 11A to maintain the bent state of the elastic portion 13A.

[0033] The spring plate 10A is made entirely of a thin sheet of a conductive material such as metal. When the conductive material is metal, stainless steel is preferred because it is easy to process and less prone to rusting.

[0034] A soft conductive member 20 is attached to the bending side surface of each elastic part 13A, and the spring plate 10A and the soft conductive member 20 constitute the electromagnetic noise suppression member 1A. The soft conductive member 20 is attached to the elastic part 13A using an adhesive or the like.

[0035] The flexible conductive member 20 is made by mixing or supporting a conductive material on a flexible base material. As the flexible base material, porous materials such as paper, cloth, nonwoven fabric, or resin sheets can be used. Alternatively, commercially available products referred to as "conductive sheets" can be used as the flexible conductive member. Examples of conductive materials include metal fibers, pulverized materials, and powders of silver, copper, gold, aluminum, stainless steel, or conductive carbon fibers, pulverized materials, and powders. In particular, it is preferable that the member be composed of at least one selected from resin-impregnated nonwoven fabric, nonwoven fabric, resin-impregnated woven fabric, woven fabric, resin-impregnated soft porous material such as sponge, and soft porous material such as sponge.

[0036] As shown in Figures 2 and 3, the bearing unit 100A according to the first embodiment is equipped with a rolling bearing and has the electromagnetic noise suppression member 1A shown in Figure 1 attached. The rolling bearing 50 has an outer ring 51 that constitutes one raceway, an inner ring 52 that constitutes the other raceway, and a plurality of rolling elements (balls) 53 that are held to roll freely between the outer ring 51 and the inner ring 52 by a cage 54. The rolling elements 53 roll smoothly with bearing lubricant such as lubricating oil or grease composition. Here, the rotating ring is the inner ring 52, and a shaft 60 that is directly connected to a motor (not shown) is fitted into the inner diameter side of the inner ring 52. The outer ring 51 is a fixed ring and is fixed to the housing 70.

[0037] The flexible conductive member 20 is mounted on the elastic portion 13A on the side facing the inner ring (rotating ring) 52 (right side in the figure), and the flexible conductive member 20 is mounted on the bearing unit 100A with the bent side facing the inner ring 52.

[0038] As shown in Figure 3, the bearing unit 100A is used with the annular portion 11A of the electromagnetic noise suppression member 1A pressed against the side surface of the outer ring 51 by a conductive pressing member 80 with a conductive spacer 30 interposed between them. Therefore, the outer diameter side of the outer ring 51 and the outer peripheral end face 15A of the annular portion 11A on the spring plate 10A are fixed in contact with the housing 70, and the soft conductive member 20 is able to contact the side surface 52a of the inner ring 52. The spring plate 10A is made of a thin plate and is elastic, so when the annular portion 11A of the electromagnetic noise suppression member 1A is pressed against the side of the outer ring 51, the elastic force due to the pressing acts on the elastic portion 13A, causing it to be pushed open so that the bending angle θ shown in Figure 1(C) becomes larger. Consequently, the portion of the soft conductive member 20 that was separated from the side surface 52a of the inner ring 52 in Figure 2 also moves towards 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.

[0039] The thickness of the spacer 30 should be determined considering the amount of pressure applied by the spring plate 10A and the thickness of the soft conductive member 20. Alternatively, the annular portion 11A of the electromagnetic noise suppression member 1A may directly contact the side surface of the outer ring 51 without the spacer 30.

[0040] In the first embodiment, the flexible conductive member 20 of the electromagnetic noise suppression member 1A is mounted on the housing 70 so as to abut against the side surface 52a of the inner ring 52. Furthermore, the annular portion 11A of the spring plate 10A is electrically connected to the side surface of the outer ring 51 via a conductive spacer 30, and is also electrically connected to the conductive retaining member 80.

[0041] As a result, in the first embodiment, current from the motor (not shown) that drives the shaft 60 flows to the inner ring 52. The current then flows from the soft conductive member 20 through the inner ring 52 to the elastic portion 13A and the annular portion 11A of the spring plate 10A, and then flows to the grounded housing 70 via the outer peripheral end face 15A of the annular portion 11A, the retaining member 80, the spacer 30 and the outer ring 51. By grounding the rotating member, the shaft 60, and the fixed member, the housing 70 in this way, the shaft voltage, which is the potential difference between the rotating member and the fixed member, can be significantly reduced. Therefore, electromagnetic noise can be dissipated through the space between the rotating member, the shaft 60, and the fixed member, the housing 70. Furthermore, because the outer ring 51 has a large contact area with the housing 70, the current flowing through the outer ring 51 does not pass through the rolling elements 53, but instead flows to the housing 70.

[0042] Furthermore, 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. In addition, since the biasing force of the soft conductive member 20 on the side surface of the inner ring 52 by the spring plate 10A is not very strong, the generation of wear particles can be suppressed.

[0043] In the first embodiment, when a porous material is selected as the flexible conductive member 20, it has oil absorption and oil retention properties, so oil is easily discharged between adjacent spring plates 10A when the shaft rotates, and it is difficult for an oil film to form, resulting in good conductivity even when used in oil. Therefore, it is more preferable for the flexible conductive member 20 in the first embodiment to be used in an oily environment without using a sealing material to seal the bearing lubricant. Furthermore, by making the base material of the flexible conductive member 20 a porous material, even when used in an environment other than an oily environment, the coefficient of friction can be suppressed, and the reduction in the rotational torque of the inner ring 52 can be suppressed.

[0044] In the first embodiment, the outer peripheral end surface 15A of the annular portion 11A and the spacer 30 are in contact with the housing 70, but they may not be in contact with the housing 70, but instead be held between the outer ring 51 and the retaining member 80. In that case, the current flowing through the annular portion 11A flows to the housing 70 via the outer ring 51 and the retaining member 80. Alternatively, the annular portion 11A of the electromagnetic noise suppression member 1A may be pressed directly against the side surface of the outer ring 51 with a conductive spacer 30 in between, without the presence of a retaining member 80, and fixed in contact with the housing 70.

[0045] Furthermore, as shown in Figure 1(C), the bending angle θ between the annular portion 11A and the elastic portion 13A can be appropriately set according to the length (L) of the elastic portion 13A and the size of the soft conductive member 20, so that when mounted on the bearing unit 100A, the soft conductive member 20 contacts the side surface 52a of the inner ring 52 of the rolling bearing 50. The biasing force of the soft conductive member 20 on the side surface 52a of the inner ring 52 of the rolling bearing 50 can also be adjusted by the bending angle θ; 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.

[0046] By adjusting the pressing force applied by the retaining member 80 to the outer ring 51, the contact area between the soft conductive member 20 of the electromagnetic noise suppression member 1A and the side surface 52a of the inner ring 52 of the rolling bearing 50 can be changed. In this case, increasing the contact area between the soft conductive member 20 and the side surface 52a of the inner ring 52 makes it possible to more effectively suppress the generation of electromagnetic noise. Furthermore, it is possible to suppress the temperature rise due to friction.

[0047] (Second embodiment: Electromagnetic noise suppression member and bearing unit for outer ring rotation) In the first embodiment, the case in which the inner ring 52 of the rolling bearing 50 is a rotating ring was described, but in the second embodiment, a bearing unit in which the outer ring 51 is a rotating ring will be described. Figure 4 shows an electromagnetic noise suppression member for outer ring rotation, with Figure 4(A) being a plan view thereof and Figure 4(B) being a cross-sectional view of Figure 4(A) AA. Figure 5 is a cross-sectional view showing how the electromagnetic noise suppression member shown in Figure 4 is mounted on the bearing unit. Figure 6 is a cross-sectional view showing an example of a bearing unit incorporating the electromagnetic noise suppression member shown in Figure 4. In the bearing unit according to the second embodiment, the same reference numerals are used for the same components as in the first embodiment, and their detailed descriptions are omitted or simplified.

[0048] As shown in Figure 4, the electromagnetic noise suppression member 1B for outer ring rotation comprises a spring plate 10B composed of an annular portion 11B and a plurality of elastic portions 13B that are bent at the outer diameter end 12B of the annular portion 11B and extend radially from the annular portion 11B toward the outer circumference in the radial direction. As shown in Figure 5, the elastic portions 13B are bent toward the right in the figure so that they face the outer ring 51 of the rolling bearing 50 when mounted on the bearing unit 100B. In addition, arc-shaped notches 16B are formed on both sides of the bent portion of the elastic portion 13B toward the annular portion 11B.

[0049] A soft conductive member 20 is attached to the surface of each elastic part 13B facing the outer ring 51 of the rolling bearing 50 using an adhesive or the like, and the spring plate 10B and the soft conductive member 20 constitute the electromagnetic noise suppression member 1B.

[0050] As shown in Figures 5 and 6, the bearing unit 100B according to the second embodiment includes a rolling bearing 50 and is fitted with the electromagnetic noise suppression member 1B shown in Figure 4. The inner ring 52 of the rolling bearing 50 is fixed to a fixing member 75, and a rotating member 65 is fitted to the outer ring 51. As shown in Figure 5, the soft conductive member 20 is fitted to the elastic portion 13B on the surface (right side in the figure) facing the outer ring (rotating ring) 51, and the bearing unit 100B is fitted with the flexible conductive member 20 with the bent side facing the outer ring 51.

[0051] Furthermore, as shown in Figure 6, the bearing unit 100B is used with the annular portion 11B of the electromagnetic noise suppression member 1B pressed against the side surface of the inner ring 52 by the retaining member 80 with a conductive spacer 30 interposed between them. Therefore, the inner diameter side of the inner ring 52 and the inner circumferential end surface of the annular portion 11B on the spring plate 10B are fixed in contact with the fixing member 75, and the soft conductive member 20 is able to contact the side surface of the outer ring 51.

[0052] In the second embodiment, current from a motor (not shown) that drives the rotating member 65 flows to the outer ring 51. The current then 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 circumferential end face 14B of the annular portion 11B, the retaining member 80, the spacer 30 and the inner ring 52 to the grounded fixed member 75. By grounding the rotating member 65 and the fixed member 75 in this way, the inside of the bearing is not energized, and the shaft voltage, which is the potential difference between the rotating member and the fixed member, can be significantly reduced. Therefore, electromagnetic noise can be reduced.

[0053] Furthermore, similar to the first embodiment, the biasing force exerted by the spring plate 10B on the side surface of the outer ring 51 of the soft conductive member 20 is not very strong, thus suppressing the generation of wear particles.

[0054] Furthermore, by adjusting the pressing force applied by the retaining member 80 to the outer ring 51 and increasing the contact area between the soft conductive member 20 and the side surface 51a of the outer ring 51, electromagnetic noise generation can be suppressed more effectively. In addition, temperature rise due to friction can be suppressed.

[0055] Furthermore, in this embodiment as well, the annular portion 11B of the electromagnetic noise suppression member 1B may directly contact the side surface of the inner ring 52 without providing the spacer 30. Furthermore, the inner circumferential end surface 14B of the annular portion 11B and the spacer 30 may be in contact with the fixing member 75, or they may not be in contact with the fixing member 75 but may be held between the inner ring 52 by the retaining member 80.

[0056] (Third embodiment: Electromagnetic noise suppression member and bearing unit for inner ring rotation) Figure 7 shows the case in which the electromagnetic noise suppression member 1A is mounted on a bearing unit in which the rotating ring is the inner ring, similar to the first embodiment. In the bearing unit according to the third embodiment, the same reference numerals are used for the same components as in the first embodiment, and their detailed descriptions are omitted or simplified.

[0057] In the third embodiment, the shaft 60, which is a rotating member into which the inner ring 52 is fitted, has a stepped surface 60c formed thereon that is smaller in diameter than the fitting surface 60b into which the inner ring 52 is fitted. The soft conductive member 20 is mounted on the surface of the elastic portion 13A that faces the shaft 60 in the axial direction, specifically on the side surface 60a between the fitting surface 60b into which the inner ring 52 is fitted and the stepped surface 60c. The electromagnetic noise suppression member 1A is mounted on the housing 70 by elastically deforming the elastic portion 13A. The annular portion 11A of the spring plate 10A and the spacer 30 are sandwiched between the flange portion 71 and the outer ring 51, which are provided to protrude toward the inner diameter side of the housing 70.

[0058] As shown in Figure 7, in this type of inner ring rotating bearing unit 100A, the soft conductive member 20 of the electromagnetic noise suppression member 1A is mounted on the housing 70 so as to abut against the side surface 60a of the shaft 60. As a result, the annular portion 11A of the spring plate 10A is electrically connected to the side surface of the outer ring 51 via the conductive spacer 30, and is also electrically connected to the end face of the flange portion 71 of the housing 70.

[0059] In the bearing unit 100A shown in Figure 7, 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. Subsequently, the current flows to the housing 70 via the spacer 30 and the outer ring 51, or via the outer peripheral end face 15A of the annular portion 11A to the grounded housing 70. In this way, by grounding the rotating member, the shaft 60, and the stationary member, the housing 70, current does not flow inside the bearing, and the shaft voltage, which is the potential difference between the rotating member and the stationary member, can be significantly reduced. Therefore, electromagnetic noise can be reduced.

[0060] Furthermore, similar to the first embodiment, the biasing force exerted by the spring plate 10A on the side surface of the shaft 60 by the soft conductive member 20 is not very strong, and wear particles are less likely to be generated.

[0061] As shown in Figure 8, in this embodiment, the shaft 60 may be provided with a flange portion 62 that protrudes outward from the fitting surface 60b, and the soft conductive member 20 may be in contact with the side surface 60a of this flange portion 62.

[0062] In particular, in the bearing unit 100A shown in Figure 7, the position where the soft conductive member 20 contacts the side surface 60a of the shaft 60 is smaller in diameter than the position where it contacts the side surface 52a of the inner ring 52, as shown in Figure 3. This allows the peripheral speed of the side surface 60a of the shaft 60 to be reduced, further suppressing the generation of wear particles and drag losses.

[0063] In the third embodiment, unlike the first embodiment, the electromagnetic noise suppression member 1A does not come into contact with the side surface 52a of the inner ring 52, thereby improving the design flexibility of the rolling bearing, such as the installation of a snap ring.

[0064] (Fourth embodiment: Electromagnetic noise suppression member and bearing unit for outer ring rotation) Figure 9 shows the case where the electromagnetic noise suppression member 1B is mounted on a bearing unit in which the rotating ring is the outer ring 51, similar to the second embodiment. In the bearing unit according to the fourth embodiment, the same reference numerals are used for the same components as in the second embodiment, and their detailed descriptions are omitted or simplified.

[0065] In the fourth embodiment, the rotating member 65 into which the outer ring 51 is fitted has a stepped surface 65c with a larger diameter than the fitting surface 65b into which the outer ring 51 is fitted. The soft conductive member 20 is mounted on the surface of the elastic portion 13B that faces the rotating member 65 in the axial direction, specifically on the surface facing the side surface 65a between the fitting surface 65b into which the outer ring 51 is fitted and the stepped surface 65c. Therefore, the soft conductive member 20 can come into contact with the side surface 65a of the rotating member 65.

[0066] As shown in Figure 9, in the outer ring rotating type bearing unit 100B, the soft conductive member 20 of the electromagnetic noise suppression member 1B is mounted on the fixed member 75 so as to abut against the side surface 65a of the rotating member 65. As a result, the annular portion 11B of the spring plate 10B is electrically connected to the side surface of the inner ring 52 via the conductive spacer 30, and is also electrically connected to the end face of the flange portion 76 of the fixed member 75.

[0067] In the bearing unit 100B shown in Figure 9, the current from the 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, through the elastic portion 13B and the annular portion 11B of the spring plate 10B, and to the inner circumferential end surface 14B of the annular portion 11B. Subsequently, the current flows to the grounded fixed member 75, or directly to the fixed member 75, via the spacer 30 and the inner ring 52. By grounding the rotating member 65 and the fixed member 75 in this way, the inside of the bearing is not energized, and the shaft voltage, which is the potential difference between the rotating member and the fixed member, can be significantly reduced. Therefore, electromagnetic noise can be reduced.

[0068] Furthermore, similar to the first embodiment, the biasing force exerted by the spring plate 10B on the side surface of the rotating member 65 by the soft conductive member 20 is not very strong, so wear particles are less likely to be generated.

[0069] As shown in Figure 10, in this embodiment, the rotating member 65 may be provided with a flange portion 67 that protrudes inward from the fitting surface 65b, and the soft conductive member 20 may come into contact with the side surface 65a of this flange portion 67.

[0070] 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 is smaller in diameter than the position where it contacts the side surface 51a of the outer ring 51, as shown in Figure 6. This allows the peripheral speed of the side surface 65a of the rotating member 65 to be reduced, further suppressing the generation of wear particles and drag losses.

[0071] Furthermore, unlike the second embodiment, the fourth embodiment does not involve contact between the electromagnetic noise suppression member 1B and the side surface 51a of the outer ring 51, thereby improving the design flexibility of the rolling bearing, such as the installation of a snap ring.

[0072] (Fifth embodiment: Electromagnetic noise suppression member and bearing unit for inner ring rotation, equipped with a single elastic part) Figure 11 shows an example of an electromagnetic noise suppression member according to the fifth embodiment of the present invention, where Figure (A) is a plan view thereof, Figure (B) is a cross-sectional view of Figure (A) AA, and Figure (C) is an enlarged view showing the bent portion between the annular portion and the elastic portion in Figure (B). Figure 12 is a cross-sectional view showing how the electromagnetic noise suppression member shown in Figure 11 is mounted on a bearing unit. Figure 13 is a cross-sectional view showing an example of a bearing unit incorporating the electromagnetic noise suppression member shown in Figure 11. In the bearing unit according to the fifth embodiment, the same reference numerals are used for the same components as in the first embodiment, and their detailed descriptions are omitted or simplified.

[0073] As shown in Figure 11, the electromagnetic noise suppression member 1C comprises a spring plate 10C which consists of an annular portion 11C and a single elastic portion 13C that is bent at the inner circumferential end 12C of the annular portion 11C and extends radially from the annular portion 11C toward the center. The elastic portion 13C is bent starting from the elastic base portion 14C. A soft conductive member 20 is attached to the bent side surface of the elastic portion 13C with adhesive or the like, and the spring plate 10C and the soft conductive member 20 constitute the electromagnetic noise suppression member 1C.

[0074] As shown in Figure 12, the electromagnetic noise suppression member 1C is mounted on the bearing unit 100C with the bent side surface (right side in the figure) of the elastic portion 13C facing the side surface 60a of the shaft 60 which is fitted into the inner ring 52 of the rolling bearing 50. The side surface 60a of the shaft 60 refers to the surface of the shaft 60 that is perpendicular to the axial direction.

[0075] Furthermore, as shown in Figure 13, the bearing unit 100C is used with the annular portion 11C of the electromagnetic noise suppression member 1C pressed against the side surface of the outer ring 51 by the retaining member 80 with the spacer 30 interposed between them. Therefore, the soft conductive member 20 can come into contact with the side surface 60a of the shaft 60. As a result, the annular portion 11C of the spring plate 10C is electrically connected to the side surface of the outer ring 51 via the conductive spacer 30, and is also electrically connected to the housing 70.

[0076] In the fifth embodiment, current from a motor (not shown) that drives the shaft 60 flows from the soft conductive member 20 to the elastic portion 13C and the annular portion 11C of the spring plate 10C, and then flows to the grounded housing 70 via the outer peripheral end face 15C of the annular portion 11C, the retaining member 80, the spacer 30 and the outer ring 51. By grounding the rotating member, the shaft 60, and the fixed member, the housing 70 in this way, current does not flow inside the bearing, and the shaft voltage, which is the potential difference between the rotating member and the fixed member, can be significantly reduced. Therefore, electromagnetic noise can be reduced.

[0077] Furthermore, similar to the first embodiment, the biasing force exerted by the spring plate 10C on the side surface of the shaft 60 by the soft conductive member 20 is not very strong, so wear particles are less likely to be generated.

[0078] Furthermore, in the fifth embodiment, the outer peripheral end face 15C of the annular portion 11C and the spacer 30 are in contact with the housing 70, but they may not be in contact with the housing 70 and may be held between the outer ring 51 and the retaining member 80. In that case, the current flowing through the annular portion 11C flows to the housing 70 via the outer ring 51 and the retaining member 80. Note that since the outer ring 51 has a large contact area with the housing 70, the current flowing through the outer ring 51 does not pass through the rolling elements 53 and flows to the housing 70.

[0079] Furthermore, in the bearing unit 100C, the soft conductive member 20 is in contact with the side surface 60a of the shaft 60, resulting in an even lower peripheral speed compared to the case where the soft conductive member 20 is in contact with the side surface of the inner ring 52. Therefore, compared to other embodiments, it is possible to further suppress the generation of wear particles and drag losses. Note that since the peripheral speed is lowest near the center of the shaft, it is more preferable for the soft conductive member 20 to be in contact near the center of the shaft.

[0080] It should be noted that the present invention is not limited to the embodiments described above, and can be modified and improved as appropriate. In the above embodiment, the elastic portions 13A, 13B, and 13C of the spring plates 10A, 10B, and 10C are configured to bend toward the rotating ring. However, they may also be formed flush with the annular portions 11A, 11B, and 11C without bending at the inner diameter end 12A, the outer diameter end 12B, and the elastic base portion 14C. For example, in the case of the electromagnetic noise suppression member 1A for inner ring rotation shown in Figure 1, the annular portion 11A and the elastic portion 13A may be linearly continuous in cross-sectional view, as shown in Figure 14. Also, for example, in the case of the electromagnetic noise suppression member 1B for outer ring rotation shown in Figure 4, the annular portion 11B and the elastic portion 13B may be linearly continuous in cross-sectional view, as shown in Figure 15. Furthermore, in the case of the electromagnetic noise suppression member 1C shown in Figure 11, the annular portion 11C and the elastic portion 13C may be linearly continuous in cross-sectional view, as shown in Figure 16.

[0081] Therefore, in the bearing units 100A and 100C shown in Figures 17 and 19, when the annular portions 11A and 11C of the electromagnetic noise suppression members 1A and 1C are sandwiched between the flange portion 71 of the housing 70 and the side surface of the outer ring 51, the elastic portions 13A and 13C of the electromagnetic noise suppression members 1A and 1C elastically deform by the thickness of the soft conductive member 20, and the bending reaction force of the spring plates 10A and 10C causes the soft conductive member 20 to come into contact with the side surface 52a of the inner ring 52 and the side surface 60a of the shaft 60, respectively. Furthermore, in the bearing unit 100B shown in Figure 18, when the annular portion 11B of the electromagnetic noise suppression member 1B is sandwiched between the flange portion 76 of the fixing member 75 and the side surface of the inner ring 52, the elastic portion 13B of the electromagnetic noise suppression member 1B elastically deforms by the thickness of the soft conductive member 20, and the bending reaction force of the spring plate 10B causes the soft conductive member 20 to come into contact with the side surface 51a of the outer ring 51. This allows the same function as in the above embodiment to be achieved.

[0082] In this case, bending of the spring plates 10A, 10B, and 10C becomes unnecessary, allowing the electromagnetic noise suppression members 1A, 1B, and 1C to be manufactured at a low cost, and also facilitating bonding between the spring plates 10A, 10B, and 10C and the soft conductive member 20.

[0083] In all embodiments, there are no restrictions on the planar shape of the flexible conductive member 20. In addition to the sector shape shown in Figure 1(A), it may also be rectangular. It may also be made up of multiple small pieces. [Explanation of Symbols]

[0084] 1A, 1B, 1C Electromagnetic noise suppression members 10A, 10B, 10C Spring Plate 11A, 11B, 11C Annular section 13A, 13B, 13C Elastic part 14B Inner circumferential end face 15A,15C Outer edge 16A, 16B Notches 20 Flexible conductive material 30 Spacers 50 Rolling bearings 51 Outer ring 51a, 52a, 60a, 65a Side view 52 Inner Ring 53 Rolling element 60 shaft 60b,65b mating surface 60c,65c step surface 62, 67, 71, 76 Flange section 65 Rotating member 70 Housing 75 Fixing member 80 Retaining member 100A, 100B, 100C Bearing Unit

Claims

1. An electromagnetic noise suppression member to be mounted on a rolling bearing unit having a rolling bearing in which one raceway is a fixed wheel and the other raceway is a rotating wheel, A spring plate made of a thin sheet of conductive material is composed of a ring-shaped portion and a plurality of elastic portions extending radially and continuously from the ring-shaped portion, A soft conductive member is mounted on the surface of the elastic portion facing the rotating wheel, Equipped with, The aforementioned flexible conductive member is capable of contacting the side surface of the rotating wheel. The flexible conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a resin-impregnated woven fabric, and a resin-impregnated flexible porous material consisting of sponge. An electromagnetic noise suppression member for rolling bearings, characterized by the above.

2. An electromagnetic noise suppression member to be mounted on a rolling bearing unit that has a rolling bearing in which one raceway is a fixed wheel and the other raceway is a rotating wheel, A spring plate made of a thin sheet of conductive material is composed of a ring-shaped portion and a plurality of elastic portions extending radially and continuously from the ring-shaped portion, In the elastic portion, a soft conductive member is mounted on the surface facing the rotating member into which the rotating ring is fitted, Equipped with, The soft conductive member is capable of contacting the side surface of the rotating member. An electromagnetic noise suppression member for rolling bearings, characterized by the above.

3. An electromagnetic noise suppression member to be mounted on a rolling bearing unit having a rolling bearing in which one raceway is a fixed wheel and the other raceway is a rotating wheel, A spring plate made of a thin sheet of conductive material is composed of an annular portion and at least one elastic portion that extends radially continuously from the annular portion, In the elastic portion, a soft conductive member is mounted on the surface facing the rotating wheel or the rotating member into which the rotating wheel is fitted, Equipped with, The soft conductive member is capable of contacting at least a portion of the surface of the rotating wheel, or at least a portion of the surface of the rotating member. The soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a resin-impregnated woven fabric, and a resin-impregnated soft porous material consisting of sponge. An electromagnetic noise suppression member for a rolling bearing, characterized in that the annular portion is pressed against the side surface of the fixed ring with a spacer interposed therebetween.

4. An electromagnetic noise suppression member to be mounted on a rolling bearing unit having a rolling bearing in which one raceway is a fixed wheel and the other raceway is a rotating wheel, A spring plate made of a thin sheet of conductive material is composed of a ring-shaped portion and a plurality of elastic portions extending radially and continuously from the ring-shaped portion, In the elastic portion, a soft conductive member is mounted on the surface facing the rotating wheel or the rotating member into which the rotating wheel is fitted, Equipped with, The soft conductive member is capable of contacting at least a portion of the surface of the rotating wheel, or at least a portion of the surface of the rotating member. The soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a resin-impregnated woven fabric, and a resin-impregnated soft porous material consisting of sponge. An electromagnetic noise suppression member for a rolling bearing, characterized in that the plurality of elastic parts are bent toward the rotating ring.

5. An electromagnetic noise suppression member to be mounted on a rolling bearing unit having a rolling bearing in which one raceway is a fixed wheel and the other raceway is a rotating wheel, A spring plate made of a thin sheet of conductive material is composed of a ring-shaped portion and a plurality of elastic portions extending radially and continuously from the ring-shaped portion, In the elastic portion, a soft conductive member is mounted on the surface facing the rotating wheel or the rotating member into which the rotating wheel is fitted, Equipped with, The soft conductive member is capable of contacting at least a portion of the surface of the rotating wheel, or at least a portion of the surface of the rotating member. The soft conductive member is composed of at least one selected from a resin-impregnated nonwoven fabric, a resin-impregnated woven fabric, and a resin-impregnated soft porous material consisting of sponge. An electromagnetic noise suppression member for a rolling bearing, characterized in that the plurality of elastic portions are formed flush with the annular portion.

6. It is equipped with a rolling bearing in which one raceway is a fixed ring and the other raceway is a rotating ring, A rolling bearing unit characterized by being equipped with an electromagnetic noise suppression member for rolling bearings as described in any one of claims 1 to 5.

7. An electromagnetic noise suppression member to be mounted on a rolling bearing unit that has a rolling bearing in which one raceway is a fixed wheel and the other raceway is a rotating wheel, The aforementioned rolling bearing is an inner-ring rotating type, in which the fixed ring is an outer ring fixed to the housing, and the rotating ring is an inner ring into which a shaft directly connected to the motor is fitted. A spring plate made of a thin sheet of conductive material is composed of an annular portion and an elastic portion that extends radially from the inner circumferential end of the annular portion toward the center of the annular portion, A soft conductive member is mounted on the surface of the elastic portion facing the rolling bearing, Equipped with, The soft conductive member is capable of contacting the side surface of the shaft. An electromagnetic noise suppression member for rolling bearings, characterized by the above.

8. The electromagnetic noise suppression member for a rolling bearing according to claim 7, characterized in that the annular portion is pressed against the side surface of the outer ring with a spacer interposed therebetween.

9. The electromagnetic noise suppression member for rolling bearing according to claim 7, characterized in that the elastic portion of the spring plate is bent toward the side of the shaft.

10. The electromagnetic noise suppression member for a rolling bearing according to claim 7, characterized in that the elastic portion of the spring plate is formed flush with the annular portion.

11. It features an inner ring rotating type rolling bearing in which the outer ring is fixed to the housing and the shaft directly connected to the motor is fitted into the inner ring, A rolling bearing unit characterized by being equipped with an electromagnetic noise suppression member for rolling bearings as described in any one of claims 7 to 10.

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