Conductive structure and conductive sealing device

Abstract

To provide a conductive structure and a conductive sealing device capable of improving abrasion resistance while providing electrical conductivity.SOLUTION: A conductive structure (1) comprises an annular conductive holding member (10), an annular conductive member (20) made of a metallic material, and an annular support member (30) made of an elastic material. The conductive member (20) and the support member (30) are held by the holding member (10) while overlapping in a direction of an axial line x. The conductive member (20) has an annular inner peripheral end part (25), and the support member (30) overlaps the conductive member (20) so as to be able to press the inner peripheral end part (25) of the conductive member (20) inward.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electrically conductive structure and an electrically conductive sealing device, and more particularly to an electrically conductive structure and an electrically conductive sealing device for forming an electrically conductive path in a rotating shaft. [Background technology]

[0002] For example, in vehicles equipped with electric motors, such as electric vehicles (EVs), electromagnetic noise can be generated by induced currents generated by the motor. Such electromagnetic noise can cause communication problems with AM radios and other wireless communication devices. Furthermore, such electromagnetic noise can cause electrolytic corrosion in metal components, such as bearings. For this reason, efforts have been made to eliminate such electromagnetic noise, and conductive structures and devices that form a conductive path in a rotating shaft have been proposed. For example, a technology has been disclosed in which a conductive structure is attached to a motor housing and a disk-shaped conductive member made of a conductive material is brought into contact with the motor's rotating shaft to form a conductive path between the rotating shaft and the housing, thereby dissipating electromagnetic noise from the rotating shaft to the housing (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2019-509007 Summary of the Invention [Problem to be solved by the invention]

[0004] Because the conductive member of the conductive structure slides against the rotating shaft, there has been a demand for a configuration of the conductive member that is conductive while being resistant to wear. For example, Patent Document 1 proposes that the conductive member be made of conductive PTFE. However, there is a demand for conventional conductive structures that have improved wear resistance while maintaining conductivity. Thus, there is a demand for conventional conductive structures that have improved wear resistance while maintaining conductivity.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a conductive structure and a conductive sealing device that can improve wear resistance while maintaining conductivity. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the conductive structure of the present invention comprises a holding member which is a conductive member having an annular shape around an axis, a conductive member which is a member formed from a metal material having an annular shape around the axis, and a support member which is a member formed from an elastic material having an annular shape around the axis, wherein the conductive member and the support member are overlapped in the axial direction and held by the holding member, the conductive member has an annular inner end portion around the axis, and the support member overlaps the conductive member so as to be able to press the inner end portion of the conductive member toward its inner circumference.

[0007] In a conductive structure according to one embodiment of the present invention, the conductive member has a contact side and a pressed side, which are a pair of annular surfaces facing each other in the axial direction, and the support member has a pressing side and a back side, which are a pair of annular surfaces facing each other in the axial direction, and the pressed side of the conductive member and the pressing side of the support member face each other.

[0008] In a conductive structure according to one aspect of the present invention, the conductive member has a plurality of through holes, and the support member extends into the plurality of through holes of the conductive member.

[0009] In the conductive structure according to one aspect of the present invention, the conductive member has a mesh structure that forms the plurality of through holes.

[0010] In a conductive structure according to one aspect of the present invention, at least a portion of the support member that extends into the plurality of through holes protrudes from the through holes.

[0011] In the conductive structure according to one aspect of the present invention, the conductive member is more flexible than the support member.

[0012] In a conductive structure according to one embodiment of the present invention, the stacked conductive member and support member have at least one gap extending radially and at least one divided body extending around the axis, the divided body having a pair of ends in the direction around the axis, and the gap connecting to the ends of the divided body.

[0013] In a conductive structure according to one embodiment of the present invention, the conductive member has one divided body and one gap, the pair of ends of the divided body are opposed in a direction around the axis, and the gap is a gap between the opposed ends of the divided bodies.

[0014] In a conductive structure according to one embodiment of the present invention, the conductive member has two of the divided bodies and also has two of the gaps, where one of the pair of ends of one of the divided bodies and one of the pair of ends of the other of the divided bodies face each other in the direction around the axis, and the other of the pair of ends of one of the divided bodies and the other of the pair of ends of the other of the divided bodies face each other in the direction around the axis, one of the gaps is formed between the one end of one of the divided bodies and the one end of the other of the divided bodies, and the other of the gaps is formed between the other end of one of the divided bodies and the other end of the other of the divided bodies.

[0015] In the conductive structure according to one aspect of the present invention, the conductive member and the support member are held by the holding member on the outer periphery side.

[0016] In the conductive structure according to one aspect of the present invention, the support member is formed from PTFE or PEEK.

[0017] In order to achieve the above-mentioned object, the conductive sealing device of the present invention is a conductive sealing device for sealing between an axis and a hole through which the axis passes, and comprises a reinforcing ring which is a ring-shaped member about an axis, an elastic body portion formed from an elastic body which is ring-shaped about the axis and attached to the reinforcing ring, and a conductive structure which is ring-shaped about the axis, and the elastic body portion has a seal lip which contacts the axis, and the conductive structure comprises a holding member which is a ring-shaped member having conductivity about the axis, a conductive member which is a ring-shaped member formed from a metal material about the axis, and a support member which is a ring-shaped member formed from an elastic material about the axis, and the conductive member and the support member overlap in the axial direction and are held by the holding member, and the conductive member has an inner end portion ring-shaped about the axis, and the support member overlaps the conductive member so that the inner end portion of the conductive member can be pressed against the axis.

[0018] In one embodiment of the conductive sealing device of the present invention, the conductive member has a contact side and a pressed side, which are a pair of annular surfaces facing each other in the axial direction, and the support member has a pressing side and a back side, which are a pair of annular surfaces facing each other in the axial direction, and the pressed side of the conductive member and the pressing side of the support member face each other.

[0019] In the conductive sealing device according to one aspect of the present invention, the conductive member has a plurality of through holes, and the support member extends into the plurality of through holes of the conductive member.

[0020] In the conductive sealing device according to one aspect of the present invention, the conductive member has a mesh structure that forms the plurality of through holes.

[0021] In one aspect of the conductive sealing device of the present invention, at least a portion of the portion of the support member that enters the plurality of through holes protrudes from the through holes.

[0022] In the conductive sealing device according to one aspect of the present invention, the conductive member is more flexible than the support member.

[0023] In one embodiment of the conductive sealing device of the present invention, the stacked conductive member and support member have at least one gap extending radially and at least one divided body extending around the axis, the divided body having a pair of ends in the direction around the axis, and the gap connecting to the ends of the divided body.

[0024] In one embodiment of the conductive sealing device of the present invention, the conductive member has one divided body and one gap, the pair of ends of the divided body are opposite to each other in a direction around the axis, and the gap is a gap between the opposite ends of the divided bodies.

[0025] In one embodiment of the conductive sealing device of the present invention, the conductive member has two divided bodies and also has two gaps, where one of the pair of ends of one of the divided bodies and one of the pair of ends of the other of the divided bodies are opposite to each other in the direction around the axis, and the other of the pair of ends of one of the divided bodies and the other of the pair of ends of the other of the divided bodies are opposite to each other in the direction around the axis, and one of the gaps is formed between the one end of one of the divided bodies and the one end of the other divided body, and the other of the gaps is formed between the other end of one of the divided bodies and the other end of the other divided body.

[0026] In the conductive sealed device according to one aspect of the present invention, the conductive member and the support member are held by the holding member on the outer circumferential side.

[0027] In the conductive sealing device according to one aspect of the present invention, the support member is made of PTFE or PEEK. [Effects of the Invention]

[0028] The conductive structure and conductive sealing device according to the present invention can improve abrasion resistance while maintaining electrical conductivity. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a cross-sectional view showing a schematic configuration of a conductive structure according to a first embodiment of the present invention, taken along a plane including an axis. [Figure 2] 2 is a cross-sectional view showing one side of the conductive structure shown in FIG. 1 with respect to an axis line. [Figure 3] 3 is an enlarged cross-sectional view of a part of the conductive member and the support member shown in FIGS. 1 and 2, taken along a plane including an axis. FIG. [Figure 4] 3 is an enlarged view of a portion of the conductive member and the support member shown in FIGS. 1 and 2, viewed from one side in the axial direction. FIG. [Figure 5] FIG. 1 is a conceptual diagram showing an example of an application of a conductive structure. [Figure 6] 6 is a cross-sectional view showing an example of a state in which a conductive structure is used in the application object shown in FIG. 5. FIG. [Figure 7] FIG. 10 is a rear view of a conductive structure according to a second embodiment of the present invention. [Figure 8] 8 is a cross-sectional view showing one side of the cross-sectional axis along line AA in FIG. 7. [Figure 9] FIG. 10 is a rear view showing a modified example of the conductive structure according to the second embodiment of the present invention. [Figure 10] 1 is a cross-sectional view showing a schematic configuration of a conductive sealing device according to an embodiment of the present invention, taken along a plane including an axis of the conductive sealing device, showing one side of the axis of the cross section; [Figure 11] FIG. 1 is a conceptual diagram showing an example of an application of the conductive sealing device. [Figure 12]12 is a cross-sectional view showing an example of a state in which the conductive sealing device is used in the application shown in FIG. 11. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that in the drawings, not all of the components are labeled with reference numerals, and some of the components may be omitted.

[0031] The conductive structure according to the embodiment of the present invention forms a conductive path in a rotating shaft, for example, forming a conductive path between the shaft and a hole through which the shaft is inserted. However, the application of the conductive structure according to the embodiment of the present invention is not limited to this. Fig. 1 is a cross-sectional view showing a cross section along a plane including an axis x, showing a schematic configuration of a conductive structure 1 according to a first embodiment of the present invention, and Fig. 2 is a cross-sectional view showing one side of the conductive structure 1 shown in Fig. 1 relative to the axis x.

[0032] As shown in FIGS. 1 and 2 , the conductive structure 1 includes a holding member 10, which is a conductive member annular about the axis x; a conductive member 20, which is a member annular about the axis x and made of a metal material; and a support member 30, which is a member annular about the axis x and made of an elastic material. The conductive member 20 and the support member 30 are held by the holding member 10 while overlapping in the direction of the axis x. The conductive member 20 has an inner peripheral end portion 25, which is the end portion on the inner periphery of the annular shape about the axis x. The support member 30 overlaps the conductive member 20 so as to be able to press the inner peripheral end portion 25 of the conductive member 20 against the inner periphery. The configuration of the conductive structure 1 will be specifically described below. The inner peripheral side is the side approaching the axis x in a direction perpendicular to the axis x (hereinafter also referred to as the radial direction) (see arrow c in FIG. 1 ), and the outer peripheral side is the side away from the axis x in the radial direction (see arrow d in FIG. 1 ).

[0033] As shown in FIGS. 1 and 2, the support member 30 is a plate-like member annular about the axis x and has a pair of annular surfaces, a pressing side surface 31 and a back surface 32, facing back to back in the direction of the axis x. As shown in FIGS. 1 and 2, the pressing side surface 31 faces one side in the direction of the axis x (hereinafter also referred to as the front side), and the back surface 32 faces the other side in the direction of the axis x (hereinafter also referred to as the back surface). Note that, as shown in FIG. 1, the front side is the side indicated by arrow a, and the back surface is the side indicated by arrow b. The support member 30 has an annular inner peripheral end 30a at its inner end and an annular outer peripheral end 30b at its outer end. The inner peripheral end 30a defines a space (through hole) penetrating the support member 30 in the direction of the axis x on the inner side. The inner peripheral end 30a extends, for example, along a circle centered on the axis x. Similarly, the outer peripheral edge 30b extends, for example, along a circle centered on the axis x.

[0034] As shown in FIGS. 1 and 2 , the support member 30 is an annular plate-shaped member extending along a plane perpendicular to the axis x. Specifically, the outer peripheral end 30b of the support member 30 and its adjacent portion, the outer peripheral end portion 34, extend along a plane perpendicular to the axis x. Furthermore, the inner peripheral end 30a of the support member 30 and its adjacent portion, the inner peripheral end portion 33, extend continuously from the outer peripheral end portion 34 along a plane perpendicular to the axis x, as shown in FIGS. 1 and 2 . The inner peripheral end portion 33 of the support member 30 does not necessarily have to extend along a plane perpendicular to the axis x. For example, the inner peripheral end portion 33 of the support member 30 may be curved so that the rear surface 32 side is concave, and the diameter of the inner peripheral end portion 33 decreases toward the rear surface side in the direction of the axis x. Furthermore, the inner peripheral end portion 33 of the support member 30 may extend along a surface that is a combination of flat and curved surfaces. The material of the support member 30 is an elastic material, such as a resin material, a rubber material, or a nonwoven fabric. Examples of resin materials for the support member 30 include PTFE (polytetrafluoroethylene), POM (polyacetal), PPS (polyphenylene sulfide), PA (polyamide), and PEEK (polyether ether ketone). The material of the support member 30 is not limited to these. The support member 30 may or may not be conductive.

[0035] The support member 30 has the above-described configuration, and when a shaft enters the space defined by the inner circumferential end 30a and comes into contact with the inner circumferential end 30a, it undergoes, for example, elastic deformation, generating a predetermined amount of pressing force toward the outer circumferential surface of the shaft (in the radial direction). That is, the material, the diameter of the inner circumferential end 30a, the thickness of the support member 30 at the inner circumferential end 33, and the like are selected so that this predetermined pressing force is generated. The thickness of the support member 30 is the distance between the pressing side surface 31 and the back surface 32.

[0036] As shown in FIGS. 1 and 2, the conductive member 20 is a plate-like member annular about the axis x, and has a pair of annular surfaces, a contact side surface 21 and a pressed side surface 22, facing back to back in the direction of the axis x. As shown in FIGS. 1 and 2, the contact side surface 21 faces the front side in the direction of the axis x, and the pressed side surface 22 faces the back side in the direction of the axis x. The conductive member 20 has an annular inner peripheral end 20a at its inner circumferential end and an annular outer peripheral end 20b at its outer circumferential end. The inner peripheral end 20a defines a space (through hole) penetrating the conductive member 20 in the direction of the axis x on its inner circumferential side. The inner peripheral end 20a extends, for example, along a circle centered on the axis x. The outer peripheral end 20b also extends, for example, along a circle centered on the axis x.

[0037] As described above, the conductive member 20 and the support member 30 overlap in the direction of the axis x. Specifically, as shown in FIGS. 1 and 2, the pressed side surface 22 of the conductive member 20 and the pressing side surface 31 of the support member 30 face each other and are in contact with each other. As shown in FIGS. 1 and 2, the conductive member 20 and the support member 30 are shaped so as to overlap and coincide with each other when viewed in the direction of the axis x. That is, the pressed side surface 22 of the conductive member 20 and the pressing side surface 31 of the support member 30 have the same or approximately the same shape and size, and the inner circumferential end 20a and the outer circumferential end 20b of the conductive member 20 and the inner circumferential end 30a and the outer circumferential end 30b of the support member 30 coincide with or approximately coincide with each other, so that the conductive member 20 and the support member 30 overlap. In this way, the conductive member 20 has an outer circumferential end portion 26 at and near the outer circumferential end portion 20b, which has a shape corresponding to the outer circumferential end portion 34 of the support member 30. Furthermore, the conductive member 20 has an inner peripheral end 25 at and near the inner peripheral end 20a that corresponds to the inner peripheral end 33 of the support member 30. As shown in FIGS. 1 and 2 , the inner peripheral end 25 of the conductive member 20 has a shape that corresponds to the inner peripheral end 33 of the support member 30 and extends along a plane perpendicular to the axis x. Note that the inner peripheral end 25 of the conductive member 20 does not have to be along a plane. The inner peripheral end 25 of the conductive member 20 may have another shape that corresponds to the inner peripheral end 33 of the support member 30. For example, if the inner peripheral end 33 of the support member 30 extends in a curved shape, the inner peripheral end 25 of the conductive member 20 will also extend in a curved shape to correspond to the inner peripheral end 33 of the support member 30.

[0038] As described above, the conductive member 20 is made of metal. As shown in FIGS. 1 and 2 , the conductive member 20 has the same or substantially the same shape as the support member 30 in the conductive structure 1. However, the conductive member 20 does not have to be soft and maintain the same or substantially the same shape as the support member 30 in its free state, or it may maintain the same or substantially the same shape as the support member 30 in its free state. For example, even if the conductive member 20 maintains the same or substantially the same shape as the support member 30 in its free state, the conductive member 20 is softer than the support member 30 and is more flexible than the support member 30. The free state of the conductive member 20 refers to a state in which the conductive member 20 is in a standalone state and is not subjected to an external force.

[0039] The conductive member 20 has, for example, a plurality of through holes. Specifically, for example, the conductive member 20 has a mesh structure that forms a plurality of through holes. For example, the conductive member 20 is a metal cloth. The mesh structure extends along the contact side surface 21 and the pressed side surface 22, and the through holes penetrate between the contact side surface 21 and the pressed side surface 22. Note that the conductive member 20 does not necessarily have to have through holes.

[0040] 3 and 4 are enlarged views of a portion of the conductive member 20 and the support member 30 shown in FIGS. 1 and 2. FIG. 3 shows a cross section along a plane including the axis x, and FIG. 4 is a view from the front side. As shown in FIGS. 3 and 4, for example, the conductive member 20 is formed of a plurality of metal wires 23 extending in a lattice pattern, with a plurality of through holes 24 formed between the plurality of metal wires 23. Note that the metal wires 23 have a structure formed from a linearly extending metal, and the plurality of metal wires 23 may be independent members or may be integrated. As shown in FIGS. 3 and 4, the plurality of metal wires 23 form a contact side surface 21 and a pressed side surface 22, and the pressed side surface 22 is in contact with the pressing side surface 31 of the support member 30.

[0041] As shown in FIG. 3 , for example, the support member 30 extends into the multiple through holes 24 of the conductive member 20. That is, portions of the pressing side surface 31 of the support member 30 facing the multiple through holes 24 protrude toward the conductive member 20, and these protruding portions extend into the multiple through holes 24. In this manner, the support member 30 has multiple protrusions 35 on the pressing side surface 31, and the multiple protrusions 35 each extend into the multiple through holes 24 of the conductive member 20. As shown in FIG. 3 , the protrusions 35 of the support member 30 may not reach the contact side surface 21 of the conductive member 20, but may protrude partway into the through holes 24. Alternatively, the protrusions 35 of the support member 30 may reach the contact side surface 21 of the conductive member 20. That is, the protrusions 35 of the support member 30 may protrude to the end of the through hole 24 on the contact side surface 21 side, or may protrude beyond the end of the through hole 24 on the contact side surface 21 side. The protrusion 35 does not necessarily have to be formed on the pressing side surface 31 of the support member 30 at the portion facing the through-hole 24 .

[0042] The conductive member 20 and the support member 30 may be made separately and then stacked together, or they may be integrally molded by insert molding. When the conductive member 20 and the support member 30 made separately are stacked together, a plurality of protrusions 35 can be formed on the pressing side surface 31 of the support member 30 by pressing or the like. When no protrusions 35 are formed on the pressing side surface 31 of the support member 30, for example, the conductive member 20 and the support member 30 can be stacked and held by the holding member 10. The conductive member 20 and the support member 30 may also be adhered to each other.

[0043] 1 and 2, the holding member 10 specifically has an inner holding member 11 located on the inside and an outer holding member 15 located on the outside. The inner holding member 11 and the outer holding member 15 are annular members around the axis x, and are configured to be able to hold the conductive member 20 and the support member 30 overlapping between them.

[0044] 2, the inner holding member 11 has, for example, a fitting portion 12 which is an annular portion about the axis x, and a holding portion 13 which is an annular portion about the axis x. The fitting portion 12 is a cylindrical portion extending along the axis x, and the holding portion 13 is an annular portion extending from the front end of the fitting portion 12 to the inner periphery. The fitting portion 12 has, for example, a cylindrical or approximately cylindrical shape with the axis x as its central axis or approximately its central axis.

[0045] 2, the outer holding member 15 has, for example, a fitting portion 16 which is an annular portion about the axis x, and a holding portion 17 which is an annular portion about the axis x. The fitting portion 16 is a cylindrical portion extending along the axis x, and the holding portion 17 is an annular portion extending from the front end of the fitting portion 16 to the inner periphery. The fitting portion 16 has, for example, a cylindrical or approximately cylindrical shape with the axis x as its central axis or approximately its central axis.

[0046] 1 and 2, the inner holding member 11 and the outer holding member 15 are adapted to be fitted together. Specifically, for example, the diameter of the outer peripheral surface 12a of the fitting portion 12 of the inner holding member 11 is larger than the diameter of the inner peripheral surface 16a of the fitting portion 16 of the outer holding member 15, and the fitting portion 12 of the inner holding member 11 is press-fitted into the inner peripheral side of the fitting portion 16 of the outer holding member 15, so that the fitting portion 12 of the inner holding member 11 and the fitting portion 16 of the outer holding member 15 are fitted together. Note that the outer peripheral surface 12a of the fitting portion 12 is an annular surface facing the outer peripheral side of the fitting portion 12, and the inner peripheral surface 16a of the fitting portion 16 is an annular surface facing the inner peripheral side of the fitting portion 16. Also, as shown in Figures 1 and 2, when the mating portion 12 of the inner holding member 11 and the mating portion 16 of the outer holding member 15 are mated with each other, the holding portion 13 of the inner holding member 11 and the holding portion 17 of the outer holding member 15 have portions that face each other in the direction of the axis x.

[0047] 1 and 2, when the inner holding member 11 and the outer holding member 15 are fitted together, the holding portion 13 of the inner holding member 11 and the holding portion 17 of the outer holding member 15 face the overlapping conductive member 20 and support member 30 in the direction of the axis x. Specifically, the back surface 32 of the outer peripheral end 34 of the support member 30 faces the holding portion 13 of the inner holding member 11, and the contact side surface 21 of the outer peripheral end 26 of the conductive member 20 faces the holding portion 17 of the outer holding member 15. Note that, as shown in FIGS. 1 and 2, the inner peripheral end 25 and the inner peripheral end 33 of the conductive member 20 and the support member 30 are located more inward than the holding portion 13 of the inner holding member 11 and more inward than the holding portion 17 of the outer holding member 15.

[0048] 2, when the inner holding member 11 and the outer holding member 15 are fitted together, the conductive member 20 and the support member 30, which are stacked on top of each other, are sandwiched at their outer peripheral ends 26 and 34 between the holding portion 13 of the inner holding member 11 and the holding portion 17 of the outer holding member 15 and pressed in the direction of the axis x, respectively. In this state, a pressing portion 18 is formed on the fitting portion 16 of the outer holding member 15, and the inner holding member 11 is fixed to the outer holding member 15. Note that the pressing portion 18 of the outer holding member 15 is a portion that comes into contact with the fitting portion 12 of the inner holding member 11 and fixes the fitting portion 12 in the direction of the axis x. In this way, the conductive member 20 and the support member 30, which are stacked on top of each other, are fixed between the inner holding member 11 and the outer holding member 15 (hereinafter also referred to as the "assembled state").

[0049] The inner holding member 11 and the outer holding member 15 are made of a conductive metal. However, the inner holding member 11 and the outer holding member 15 may be made of other conductive materials.

[0050] The components of the conductive structure 1 have the configurations described above, and are assembled to form the conductive structure 1 shown in FIGS. 1 and 2 . In the conductive structure 1, the fitting portion 12 of the inner holding member 11 is fitted into the fitting portion 16 of the outer holding member 15, and the fitting portion 12 of the inner holding member 11 is pressed toward the front side by the pressing portion 18 of the fitting portion 16 of the outer holding member 15. The conductive member 20 and the support member 30, which are stacked on top of each other, are sandwiched between the holding portion 13 of the inner holding member 11 and the holding portion 17 of the outer holding member 15. The conductive member 20 and the support member 30 are held by the inner holding member 11 and the outer holding member 15 at their outer peripheral ends 26 and 34, respectively. In this way, the inner holding member 11 is fixed to the outer holding member 15, and the conductive member 20 and the support member 30 are fixed between the inner holding member 11 and the outer holding member 15. Furthermore, the conductive member 20 and the support member 30 are attached to the inner holding member 11 and the outer holding member 15, respectively, so that the contact side surface 21 of the conductive member 20 comes into contact with the shaft in a usage state described below. As shown in Figures 1 and 2, the conductive member 20 and the support member 30 are attached to the inner holding member 11 and the outer holding member 15, respectively, so that the contact side surface 21 of the conductive member 20 faces the front side, but the conductive member 20 and the support member 30 may also be attached to the inner holding member 11 and the outer holding member 15, respectively, so that the contact side surface 21 of the conductive member 20 faces the rear side.

[0051] 1 and 2, the fitting portion 16 of the outer holding member 15 does not need to have the pressing portion 18. For example, the overlapping conductive member 20 and support member 30 may be attached to the outer holding member 15 whose fitting portion 16 does not have the pressing portion 18 formed thereon, and then the fitting portion 12 of the inner holding member 11 may be attached to the fitting portion 16 of the outer holding member 15, and then the pressing portion 18 may be formed on the fitting portion 16. In other words, the pressing portion 18 may be formed to crimp the fitting portion 12 and the fitting portion 16 together, and the pressing portion 18 may press the end of the fitting portion 12 toward the front, thereby bringing the conductive member 20, support member 30, inner holding member 11, and outer holding member 15 into the assembled state as shown in FIGS.

[0052] Next, the operation of the conductive structure 1 will be described. FIG. 5 is a conceptual diagram illustrating an example of an application of the conductive structure 1. FIG. 6 is a cross-sectional view illustrating an example of a state in which the conductive structure 1 is used in the application shown in FIG. 5. As an example, the conductive structure 1 is applied to a drive device 100 of a battery electric vehicle (BEV) as shown in FIG. 5. As shown in FIG. 5, the drive device 100 includes an electric motor 101, a reduction gear 102, an inverter 103 that controls the electric motor 101, and a battery 104 as a power source. In the electric motor 101, a shaft 110 is rotatably supported by a bearing 112 supported in a housing 111 and extends outside the housing 111 through a shaft hole 113 in the housing 111. The shaft 110 of the electric motor 101 enters the housing 120 through a shaft hole 124 in the housing 120 of the reduction gear 102 and is rotatably supported by a bearing 123 supported in the housing 120. The shaft 110 is connected to a reduction gear stage 121 in a housing 120. The reducer 102 is provided with a shaft 122 that outputs a rotational driving force reduced by the reduction gear stage 121. The shaft 122 is rotatably supported by a bearing 123 supported in the housing 120, and is connected to the wheels 105 so as to transmit the rotational driving force to the wheels 105. An oil seal 125 is attached to a shaft hole 124 of the housing 120 of the reducer 102 to seal a gap between the shaft hole 124 and the shaft 110 of the electric motor 101. An oil seal 127 is attached to a shaft hole 126 of the housing 120, through which the shaft 122 of the reducer 102 passes, to seal a gap between the shaft hole 126 and the shaft 122. The shaft 110 and housing 111 of the electric motor 101 are made of metal, and the housing 120 and shaft 122 of the reducer 102 are also made of metal.

[0053] For example, the conductive structure 1 is disposed between a housing 111 and a shaft 110 of an electric motor 101 and is in a usable state. Specifically, as shown in FIG. 6 , the fitting portion 16 of the outer holding member 15 of the holding member 10 is fitted into the axial hole 113 of the housing 111 to fix the conductive structure 1 to the axial hole 113, and the shaft 110 is inserted into the conductive member 20 and the support member 30, thereby putting the conductive structure 1 into a usable state. In the usable state, the contact side surface 21 of the inner circumferential end portion 25 of the conductive member 20 is in contact with the outer circumferential surface 110a of the shaft 110, and the inner circumferential end portion 25 of the conductive member 20 is deformed by being pressed outward by the shaft 110. As shown in FIG. 6 , the inner circumferential end portion 25 of the conductive member 20 is in contact with the outer circumferential surface 110a of the shaft 110, with a width in the direction of the axis x. Furthermore, the holding members 10 (inner holding member 11 and outer holding member 15) to which the conductive member 20 is attached are made of a conductive metal and are in contact with the inner peripheral surface 113a of the shaft hole 113 of the housing 111. In this way, the conductive member 20 and the holding members 10 form a conductive path that allows electricity to flow between the shaft 110 of the electric motor 101 and the housing 111 when in use.

[0054] 6 , the support member 30 overlaps the conductive member 20 from the rear side, and the pressing side surface 31 of the support member 30 contacts the pressed side surface 22 of the conductive member 20. As described above, in use, the inner peripheral end portion 25 of the conductive member 20 is deformed by the reaction force from the shaft 110 toward the outer periphery, and the inner peripheral end portion 33 of the support member 30 is also deformed by the reaction force from the shaft 110 toward the outer periphery via the inner peripheral end portion 25 of the conductive member 20. Because the inner peripheral end portion 33 of the support member 30 has elasticity as described above, the inner peripheral end portion 33 of the support member 30 is elastically deformed, and a reaction force is generated at the inner peripheral end portion 33 of the support member 30 in response to the force from the shaft 110. Due to the reaction force of this support member 30, the conductive member 20 is pressed against the outer peripheral surface 110a of the shaft 110, and the contact side surface 21 of the conductive member 20 is pressed toward the shaft 110 and comes into contact with the outer peripheral surface 110a of the shaft 110.

[0055] In this way, in use, the conductive member 20 is pressed against the outer peripheral surface 110a of the shaft 110 by the reaction force of the support member 30, thereby ensuring strong contact between the conductive member 20 and the shaft 110. In addition, the ability of the inner peripheral end portion 25 of the conductive member 20 to follow the shaft 110 is improved, which also ensures strong contact between the conductive member 20 and the shaft 110. In this way, in the conductive structure 1, the contact between the conductive member 20 and the shaft 110 is stable. Therefore, the conductive path between the shaft 110 and the housing 111 of the electric motor 101 can be a conductive path that allows a stable flow of electricity.

[0056] 3 and 4 , when the protrusions 35 formed on the pressing side surface 31 of the support member 30 enter the multiple through-holes 24 of the conductive member 20 and protrude beyond the contact side surface 21 of the conductive member 20, the protrusions 35 of the support member 30 also come into contact with the outer circumferential surface 110a of the shaft 110 in addition to the conductive member 20. If the support member 30 is made of a material that has higher lubrication properties than a metal material, such as a resin material, the protrusions 35 protruding from the through-holes 24 come into contact with the shaft 110, thereby providing a lubricating effect to the shaft 110 that slides relative to the conductive member 20. This allows the shaft 110 to slide smoothly relative to the conductive member 20, thereby suppressing wear of the conductive member 20. Furthermore, even if the protrusion 35 does not protrude from the through-hole 24, when the protrusion 35 protrudes from the through-hole 24 due to wear of the conductive member 20, the protrusion 35 comes into contact with the shaft 110, and can provide a lubricating effect to the shaft 110 sliding relative to the conductive member 20. In this way, the protrusion 35 formed on the pressing side surface 31 of the support member 30 can improve the wear resistance of the conductive member 20.

[0057] Furthermore, in use, the conductive member 20 is supported by the support member 30 and is in stable contact with the shaft 110. This allows the rigidity of the conductive member 20 to be reduced. Furthermore, the conductive member 20 has a mesh structure with a plurality of through holes 24, and this configuration also reduces the rigidity of the conductive member 20. This allows the conductive member 20 to make smooth contact with the shaft 110. This improves the wear resistance of the conductive member 20. The rigidity of the conductive member 20 can be adjusted by changing the number of through holes 24, the diameter of the metal wire 23, the type of metal material used to make the conductive member 20, and the like. The rigidity of the conductive member 20 can also be adjusted by making cuts in the conductive member 20.

[0058] The conductive structure 1 may also be provided between the housing 120 and the shaft 122 of the reducer 102. Specifically, as shown in Fig. 5 , the conductive structure 1 may be provided outside the oil seal 127, in the gap between the shaft hole 126 of the housing 120 and the shaft 122. In this case, as with the conductive structure 1 attached to the electric motor 101, the conductive member 20 and the support member 30 of the conductive structure 1 and the holding member 10 form a conductive path that allows electricity to flow between the shaft 122 of the reducer 102 and the housing 120.

[0059] The drive unit 100 described above is an example of an application of the conductive structure 1, and the application of the conductive structure 1 is not limited thereto. The conductive structure 1 is used, for example, in drive units for battery electric vehicles (BEVs), hybrid vehicles (HVs), fuel cell vehicles (FCVs), and other electric vehicles (EVs). In vehicles equipped with electric motors, such as electric vehicles (EVs), electromagnetic noise can be generated by induced currents generated by the motor. Electromagnetic noise can also be generated by the on / off operation of an inverter for controlling current supplied to an electric motor, or by the induced voltage of the electric motor itself. As described above, the conductive structure 1 forms a conductive path and directs electromagnetic noise transmitted to the shafts 110 and 122 to the housings 111 and 120. This can prevent communication failures and malfunctions in electronic devices and electrolytic corrosion in metal components, such as bearings.

[0060] As described above, the conductive structure 1 can improve the wear resistance of the conductive member 20. Therefore, it is not necessary to provide a conductive lubricant between the conductive member 20 and the shafts 110, 122 to suppress wear and settling of the conductive member 20. Therefore, there is no lubricant that could become resistance in the conductive path between the shafts 110, 122 and the housings 111, 120, and it is possible to suppress a decrease in the conductive performance of the conductive structure 1 during use.

[0061] Furthermore, the conductive structure 1 can be attached around the shaft 110 by fitting the retaining member 10 into the axial hole 113 of the housing 111, as shown in FIG. 6 . Thus, only an annular space surrounding the outer peripheral surface 110a of the shaft 110 is required to attach the conductive structure 1. If there is space to attach the conductive structure 1 between the outer peripheral surface 110a of the shaft 110 and the inner peripheral surface 113a of the axial hole 113, the conductive structure 1 can be attached to the axial hole 113, eliminating the need to provide additional space in the housing 111 for attaching the conductive structure 1. Even if there is no space to attach the conductive structure 1 between the outer peripheral surface 110a of the shaft 110 and the inner peripheral surface 113a of the axial hole 113, the cross section of the conductive structure 1 is not large, so it is sufficient to provide only a small annular space on the inner peripheral surface 113a of the axial hole 113 for attaching the conductive structure 1. Thus, the conductive structure 1 can reduce the space required for attachment, thereby saving space.

[0062] As described above, the conductive structure 1 according to the first embodiment of the present invention can improve the wear resistance while maintaining electrical conductivity.

[0063] Next, a conductive structure 2 according to a second embodiment of the present invention will be described. FIG. 7 is a rear view of the conductive structure 2 according to the second embodiment of the present invention, and FIG. 8 is a cross-sectional view showing one side of the cross section along line AA in FIG. 7 relative to the axis x. FIG. 7 shows the conductive structure 2 in a state in which the shaft 110 is inserted, in an operational state, and FIG. 8 shows the conductive structure 2 in an assembled state, in which the shaft 110 is not inserted. Note that in FIG. 8, the reference numerals in parentheses indicate the configuration on the opposite side of the cross section. The conductive structure 2 differs from the conductive structure 1 described above in the configuration of the conductive members and support members. Hereinafter, regarding the configuration of the conductive structure 2, components that are the same as or have similar functions to those of the conductive structure 1 described above will be assigned the same reference numerals and their description will be omitted, and components that differ from the conductive structure 1 will be described.

[0064] 7 and 8, the conductive structure 2 has a conductive member 40 and a support member 50 that are different from the conductive member 20 and the support member 30, respectively, of the conductive structure 1. In the conductive structure 2, the conductive member 40 and the support member 50 are also stacked on top of each other and held by the holding member 10, similar to the conductive member 20 and the support member 30 of the conductive structure 1.

[0065] 7 and 8, in the conductive structure 2, the stacked conductive member 40 and support member 50 have at least one gap 3 extending in the radial direction and at least one divided body 4 extending around the axis x. The divided body 4 has a pair of ends 4a, 4b in the direction around the axis x. The gap 3 is continuous with the ends 4a, 4b of the divided body 4.

[0066] As shown in FIGS. 7 and 8, the stacked conductive member 40 and support member 50 form, for example, an annular plate-like structure in the conductive structure 2, which is composed of two gaps 3 (gaps 3A and 3B) and two segments 4 (segments 4A and 4B). As shown in FIGS. 7 and 8, segment 4A has a pair of ends 4Aa and 4Ab, and segment 4B has a pair of ends 4Ba and 4Bb. One of the pair of ends (end 4Aa) of one segment 4 (segment 4A) and one of the pair of ends (4Ba) of the other segment 4 (segment 4B) face each other in the direction around axis x (circumferential direction). Furthermore, the other of the pair of ends (end 4Ab) of segment 4A faces each other in the direction around axis x (circumferential direction). One side of the gap 3 (gap 3A) is formed between end 4Aa of the divided body 4A and end 4Ba of the divided body 4B, and the other side of the gap 3 (gap 3B) is formed between end 4Ab of the divided body 4A and end 4Bb of the divided body 4B.

[0067] Divided bodies 4A and 4B are members corresponding to portions of the overlapping conductive members 20 and supporting members 30 of the conductive structure 1 shown in FIGS. 1 to 4, and divided bodies 4A and 4B respectively coincide or approximately coincide with portions of the overlapping conductive members 20 and supporting members 30 of the conductive structure 1. Divided bodies 4A and 4B are formed, for example, by dividing the overlapping conductive members 20 and supporting members 30 shown in FIGS. 1 to 4 so as to form gaps 3A and 3B. Note that, for this reason, the cross-sectional shape of divided bodies 4A and 4B taken along a plane including axis x is the same as the cross-sectional shape of the overlapping conductive members 20 and supporting members 30 of the conductive structure 1 shown in FIG. 2 (see FIG. 8).

[0068] 8, the divided body 4A has a conductive member piece 20A and a support member piece 30A. The conductive member piece 20A is a member corresponding to a part of the conductive member 20 of the conductive structure 1, and the support member piece 30A is a member corresponding to a part of the support member 30 of the conductive structure 1. The divided body 4B has a conductive member piece 20B and a support member piece 30B. The conductive member piece 20B is a member corresponding to a part of the conductive member 20 of the conductive structure 1, and the support member piece 30B is a member corresponding to a part of the support member 30 of the conductive structure 1. Therefore, the conductive member piece 20A has the same cross-sectional shape as the conductive member 20, and has an inner peripheral end 20Aa, an outer peripheral end 20Ab, a contact side surface 21A, a pressed side surface 22A, an inner peripheral end 25A, and an outer peripheral end 26A, which correspond to parts of the inner peripheral end 20a, outer peripheral end 20b, contact side surface 21, pressed side surface 22, inner peripheral end 25, and outer peripheral end 26, respectively, of the conductive member 20. The conductive member piece 20A is also configured in the same manner as the conductive member 20, and has, for example, a plurality of metal wires 23 and a plurality of through holes 24. Similarly, the conductive member piece 20B has the same cross-sectional shape as the conductive member 20, and has an inner peripheral end 20Ba, an outer peripheral end 20Bb, a contact side surface 21B, a pressed side surface 22B, an inner peripheral end 25B, and an outer peripheral end 26B, which correspond to parts of the inner peripheral end 20a, the outer peripheral end 20b, the contact side surface 21, the pressed side surface 22, the inner peripheral end 25, and the outer peripheral end 26, respectively, of the conductive member 20. The conductive member piece 20B is also configured similarly to the conductive member 20, and has, for example, a plurality of metal wires 23 and a plurality of through holes 24.

[0069] The support member piece 30A has the same cross-sectional shape as the support member 30 and has an inner peripheral end 30Aa, an outer peripheral end 30Ab, a pressing side surface 31A, a back surface 32A, an inner peripheral end 33A, and an outer peripheral end 34A, which correspond to portions of the inner peripheral end 30a, the outer peripheral end 30b, the pressing side surface 31, the back surface 32, the inner peripheral end 33, and the outer peripheral end 34 of the support member 30. Similarly, the support member piece 30B has the same cross-sectional shape as the support member 30 and has an inner peripheral end 30Ba, an outer peripheral end 30Bb, a pressing side surface 31B, a back surface 32B, an inner peripheral end 33B, and an outer peripheral end 34B, which correspond to portions of the inner peripheral end 30a, the outer peripheral end 30b, the pressing side surface 31, the back surface 32, the inner peripheral end 33, and the outer peripheral end 34 of the support member 30. Similarly to the support member 30, the support member pieces 30A and 30B have multiple protrusions 35.

[0070] In the divided body 4A, the conductive member piece 20A and the support member piece 30A overlap, similar to the conductive member 20 and the support member 30. Specifically, the pressed side surface 22A of the conductive member piece 20A and the pressing side surface 31A of the support member piece 30A are in contact. The pressed side surface 22A of the conductive member piece 20A and the pressing side surface 31A of the support member piece 30A have the same or approximately the same shape and size, and the inner circumferential end 20Aa and the outer circumferential end 20Ab of the conductive member piece 20A and the inner circumferential end 30Aa and the outer circumferential end 30Ab of the support member piece 30A are aligned or approximately aligned with each other. The conductive member piece 20A has a pair of circumferential ends 20Ac and 20Ad, and the support member piece 30A has a pair of circumferential ends 30Ac and 30Ad. The end 20Ac of the conductive material piece 20A and the end 30Ac of the support material piece 30A overlap to form the end 4Aa of the divided body 4A, and the end 20Ad of the conductive material piece 20A and the end 30Ad of the support material piece 30A overlap to form the end 4Ab of the divided body 4A.

[0071] Similarly, in the divided body 4B, the conductive member piece 20B and the support member piece 30B overlap, similar to the conductive member 20 and the support member 30. Specifically, the pressed side surface 22B of the conductive member piece 20B and the pressing side surface 31B of the support member piece 30B are in contact. Furthermore, the pressed side surface 22B of the conductive member piece 20B and the pressing side surface 31B of the support member piece 30B have the same or approximately the same shape and size, and the inner peripheral end 20Ba and the outer peripheral end 20Bb of the conductive member piece 20B coincide with or approximately coincide with the inner peripheral end 30Ba and the outer peripheral end 30Bb of the support member piece 30B, respectively. The conductive member piece 20B has a pair of circumferential ends 20Bc and 20Bd, and the support member piece 30B has a pair of circumferential ends 30Bc and 30Bd. The end 20Bc of the conductive material piece 20B and the end 30Bc of the support material piece 30B overlap to form the end 4Ba of the divided body 4B, and the end 20Bd of the conductive material piece 20B and the end 30Bd of the support material piece 30B overlap to form the end 4Bb of the divided body 4B.

[0072] As described above, the segments 4A and 4B each correspond to a portion of the stacked conductive member 20 and support member 30, and are plate-like members extending along an arc around the axis x, as shown in FIG. 7. The segments 4A and 4B extend, for example, along an arc or an approximate arc centered or approximately centered on the axis x. Specifically, as shown in FIG. 7, the segments 4A and 4B extend in the circumferential direction so that the length of the arc is shorter than the semicircle along which the segments 4A and 4B extend. In other words, the segment 4A (the conductive member piece 20A and the support member piece 30A) extends in the circumferential direction so that both ends 4Aa and 4Ab of the segment 4A are located on a plane including the axis x, and do not extend beyond a plane including the axis x. 7, ends 4Aa, 4Ab of divided body 4A extend, for example, parallel or approximately parallel to a plane including axis x and face in a direction perpendicular to axis x. Note that ends 4Aa, 4Ab of divided body 4A do not have to extend parallel to a plane including axis x.

[0073] The divided body 4B (the conductive member piece 20B and the support member piece 30B) has a shape similar to that of the divided body 4A, and the divided body 4B extends in the circumferential direction so that the ends 4Ba and 4Bb of the divided body 4B are both located on a plane including the axis x or do not extend beyond a plane including the axis x. As shown in FIG. 7, the ends 4Ba and 4Bb of the divided body 4B extend, for example, parallel or approximately parallel to the plane including the axis x and face in a direction perpendicular to the axis x. Note that the ends 4Ba and 4Bb of the divided body 4B do not have to extend parallel to the plane including the axis x. Note that the divided body 4B does not have to be formed in the same manner as the divided body 4A or have the same shape as the divided body 4A.

[0074] As described above, the conductive member 40 has conductive member pieces 20A and 20B, and the support member 50 has support member pieces 30A and 30B. Furthermore, the divided body 4A is formed by stacking the conductive member piece 20A and the support member piece 30A on top of each other, and the divided body 4B is formed by stacking the conductive member piece 20B and the support member piece 30B on top of each other. As shown in FIG. 7 , in the conductive structure 2, the divided bodies 4A and 4B and the gaps 3A and 3B, which are the respective components, are located on a circle or an approximate circle centered or approximately centered on the axis x. Specifically, for example, the divided bodies 4A and 4B are arranged symmetrically with respect to a plane including the axis x. Furthermore, the divided bodies 4A and 4B are arranged so that the inner peripheral end 20Aa of the conductive member piece 20A and the inner peripheral end 20Ba of the conductive member piece 20B are located on a circle or an approximate circle centered or approximately centered on the axis x. End 4Aa of segment 4A and end 4Ba of segment 4B face each other in a direction perpendicular to axis x, and end 4Ab of segment 4A and end 4Bb of segment 4B face each other in a direction perpendicular to axis x. As a result, a gap 3A is formed between end 4Aa of segment 4A and end 4Ba of segment 4B, and a gap 3B is formed between end 4Ab of segment 4A and end 4Bb of segment 4B. In this way, gap 3A is continuous between end 4Aa of segment 4A and end 4Ba of segment 4B, and gap 3B is continuous between end 4Ab of segment 4A and end 4Bb of segment 4B.

[0075] The conductive structure 2 is used in the same manner as the conductive structure 1 described above, and forms a conductive path between the shaft 110 and the housing 111 of the electric motor 101. The conductive structure 2 also functions in the same manner as the conductive structure 1 described above, and provides the same effects.

[0076] Furthermore, in the conductive structure 2, the segments 4A, 4B are arranged in an annular shape with gaps 3A, 3B interposed between them. Therefore, even if an external force is applied to the segments 4A, 4B due to rotation of the shaft 110 during use, the segments 4A, 4B can escape to the gaps 3A, 3B. This prevents the conductive member pieces 20A, 20B and the support member pieces 30A, 30B from being deformed or coming into contact with the shaft 110, which would cause stress concentration. This prevents wear of the conductive member pieces 20A, 20B and sagging of the conductive member pieces 20A, 20B and the support member pieces 30A, 30B.

[0077] Furthermore, in the conductive structure 2, the divided bodies 4A, 4B are arranged in an annular shape with gaps 3A, 3B interposed between them. Therefore, when the conductive member pieces 20A, 20B and the support member pieces 30A, 30B are fixed to the holding member 10, the conductive member pieces 20A, 20B and the support member pieces 30A, 30B can escape to the gaps 3A, 3B. This makes it possible to prevent the conductive member pieces 20A, 20B and the support member pieces 30A, 30B from being deformed, such as wrinkled, when the conductive member pieces 20A, 20B and the support member pieces 30A, 30B are fixed to the holding member 10.

[0078] As shown in FIGS. 7 and 8 , the side surface 17a of the holding portion 17 of the outer holding member 15 may have protrusions 5a and 5b, which protrude toward the back surface, at circumferential positions corresponding to the gaps 3A and 3B between the segments 4A and 4B, respectively. In the conductive structure 2, the protrusion 5a is accommodated in the gap 3A, and the protrusion 5b is accommodated in the gap 3B. In the gap 3A, the protrusion 5a is adapted to contact the end 4Aa of the segment 4A and the end 4Ba of the segment 4B, and in the gap 3B, the protrusion 5b is adapted to contact the end 4Ab of the segment 4A and the end 4Bb of the segment 4B. In the gap 3A, a gap may be formed between the protrusion 5a and the end 4Aa of the segment 4A. In the gap 3A, a gap may be formed between the protrusion 5a and the end 4Ba of the segment 4B. Similarly, in the gap 3B, a gap may be formed between the protrusion 5b and the end 4Ab of the segment 4A. Furthermore, a gap may be formed between the protrusion 5b and the end 4Bb of the divided body 4B in the gap 3B. The protrusions 5a and 5b may be provided on the side surface 13a of the holding portion 13 of the inner holding member 11, rather than on the side surface 17a of the holding portion 17 of the outer holding member 15, so as to be similarly accommodated in the gaps 3A and 3B, respectively. The protrusions 5a and 5b may also be provided on the side surface 13a of the holding portion 13 of the inner holding member 11, in addition to the side surface 17a of the holding portion 17 of the outer holding member 15. A plurality of protrusions 5a may be provided. A plurality of protrusions 5b may also be provided. The protrusions 5a and 5b can prevent the divided bodies 4A and 4B from rotating relative to the holding member 10.

[0079] As described above, the conductive structure 2 according to the second embodiment of the present invention can improve the wear resistance while maintaining electrical conductivity.

[0080] Next, a modified example of the conductive structure 2 will be described. FIG. 9 is a rear view illustrating a modified example of the conductive structure 2, showing a divided body 4C according to the modified example. As shown in FIG. 9, the conductive structure 2 according to the modified example has one divided body 4C as the divided body 4 and one gap 3C as the gap 3. The conductive structure 2 according to the modified example does not have either the gap 3A or the gap 3B, and the divided body 4A or the divided body 4B extends into one portion of the gap 3A or the gap 3B, and the divided body 4A and the divided body 4B are connected to each other at one portion of the gap 3A or the gap 3B to form one divided body 4C. As shown in FIG. 9, the divided body 4C of the conductive structure 2 according to the modified example extends, for example, on a circle or an approximate circle centered or approximately centered on the axis x, and the end 4Ca and the end 4Cb face each other in the circumferential direction, specifically, for example, in a direction perpendicular to the axis x. Like the segments 4A and 4B, the segment 4C has a conductive member piece 20C that corresponds to a part of the conductive member 20 of the conductive structure 1, and a support member piece 30C that corresponds to a part of the support member 30 of the conductive structure 1. The conductive structure 2 may have three or more gaps 3 and three or more segments 4. In this case, the multiple gaps 3 and multiple segments 4 are also connected in a ring shape. In this modification, only one of the protrusions 5a and 5b is provided.

[0081] Next, a conductive sealing device 6 according to a first embodiment of the present invention will be described. Fig. 10 is a cross-sectional view showing one side of the axis x of a cross section taken along a plane including the axis x of the conductive sealing device 6, showing a schematic configuration of the conductive sealing device 6. The conductive sealing device 6 is a sealing device for achieving a seal between a shaft of an application object and a hole through which the shaft passes, and is also a conductive structure that forms a conductive path between the shaft and the hole through which the shaft passes.

[0082] As shown in FIG. 10 , the conductive sealing device 6 includes a reinforcing ring 60 that is an annular member about the axis x, an elastic body portion 70 that is attached to the reinforcing ring 60 and is formed from an elastic body that is annular about the axis x, and a conductive structure 7 that is annular about the axis x. The elastic body portion 70 has a seal lip 71 that contacts the axis. The conductive structure 7 includes a holding member 80 that is an annular member about the axis x, and the above-mentioned conductive member 20 and support member 30. The conductive member 20 and support member 30 overlap and are held by the holding member 80, similar to the conductive member 20 and support member 30 in the above-mentioned conductive structure 1. The configuration of the conductive sealing device 6 will be specifically described below.

[0083] As shown in FIG. 10 , the conductive sealing device 6 has a reinforcing ring 60 and an elastic body portion 70 similar to, for example, a known oil seal, and the reinforcing ring 60 has a tubular portion 61 and an annular portion 62. The elastic body portion 70 has a seal lip 71, a base portion 72, a gasket portion 73, and a cover portion 74. The seal lip 71 extends from the base portion 72 toward the object to be sealed. The gasket portion 73 is a portion that covers the tubular portion 61 of the reinforcing ring 60 from the outer periphery and is a portion that is press-fitted into a hole of the object to be sealed. The outer periphery 73a of the gasket portion 73 has a diameter that allows it to be pressed against the hole of the object to be sealed. The cover portion 74 is a portion that covers the annular portion 62 of the reinforcing ring 60 from the side opposite the object to be sealed.

[0084] As shown in FIG. 10 , an outer peripheral end (outer peripheral end 74a) of the cover portion 74 is formed with a fitting surface 75, which is an annular surface facing the outer peripheral side. The fitting surface 75 is, for example, a cylindrical surface extending along a cylindrical surface with the axis x as its central axis. Specifically, the fitting surface 75 is, for example, a cylindrical surface or an approximately cylindrical surface with the axis x as its central axis or approximately central axis. As shown in FIG. 10 , for example, the fitting surface 75 is located more outer peripherally than other portions of the outer peripheral end 74a, and an annular recess 76 recessed inward is formed between the fitting surface 75 and the gasket portion 73. The fitting surface 75 of the cover portion 74 is located more inner radially than the outer peripheral surface 73a of the gasket portion 73.

[0085] The cover part 74 also has a holding surface 77, which is an annular surface facing the side opposite to the sealed object. The holding surface 77 is, for example, a surface extending along a plane perpendicular to the axis x. Specifically, the holding surface 77 is, for example, a surface extending on a plane parallel or approximately parallel to the plane perpendicular to the axis x.

[0086] As shown in FIG. 10 , the holding member 80 of the conductive structure 7 has a similar configuration to the outer holding member 15 of the holding member 10 of the conductive structure 1 described above. The holding member 80 is made of the same conductive material as the outer holding member 15. As shown in FIG. 10 , the holding member 80 has, for example, a fitting portion 81 that is an annular portion about the axis x and a holding portion 82 that is an annular portion about the axis x. The fitting portion 81 is a cylindrical portion extending along the axis x, and the holding portion 82 is an annular portion extending from the front end of the fitting portion 81 to the inner circumferential side. As shown in FIG. 10 , the fitting portion 81 has, for example, an outer peripheral surface 81 a and an inner peripheral surface 81 b that are surfaces facing each other in the radial direction. The outer peripheral surface 81 a is an annular surface facing the outer circumferential side, and the inner peripheral surface 81 b is an annular surface facing the inner circumferential side. The inner peripheral surface 81b is a cylindrical surface extending along the axis x, for example, a cylindrical surface or a substantially cylindrical surface with the axis x as its central axis or a substantially central axis. As shown in Fig. 10, the holding portion 82 has, for example, side surfaces 82a and 82b that are surfaces facing each other in the direction of the axis x. The side surface 82b connected to the inner peripheral surface 81b of the fitting portion 81 extends along a plane perpendicular to the axis x, for example, on a plane parallel or substantially parallel to the plane perpendicular to the axis x.

[0087] The fitting portion 81 of the holding member 80 is capable of fitting into the outer peripheral end portion 74a of the cover portion 74 of the elastic body portion 70. Specifically, for example, the diameter of the inner peripheral surface 81b of the fitting portion 81 is smaller than the diameter of the fitting surface 75 of the outer peripheral end portion 74a of the cover portion 74. As a result, the cover portion 74 of the elastic body portion 70 is press-fitted into the fitting portion 81 of the holding member 80, and the holding member 80 is fixed to the elastic body portion 70.

[0088] As shown in FIG. 10 , the overlapping conductive member 20 and support member 30 are held between the holding portion 82 of the holding member 80 and the holding surface 77 of the cover portion 74 of the elastic body portion 70. Specifically, the side surface 82b of the holding member 80 contacts the back surface 32 of the outer peripheral end portion 34 of the support member 30, pressing the outer peripheral end portion 25 of the conductive member 20 against the holding surface 77 of the cover portion 74. As described above, the fitting portion 81 of the holding member 80 is fitted into the outer peripheral end portion 74a of the cover portion 74 of the elastic body portion 70, and the holding portion 82 presses the support member 30 and the conductive member 20 against the holding surface 77 of the cover portion 74, thereby fixing the holding member 80 to the elastic body portion 70. Note that a protrusion 83 that is received in the recess 76 of the cover portion 74 may be provided on the end portion 81c of the fitting portion 81 of the holding member 80 (see FIG. 10 ). As described above, when the fitting portion 81 of the retaining member 80 is fitted into the outer peripheral end portion 74a of the cover portion 74 of the elastic body portion 70, the convex portion 83 is accommodated in the concave portion 76, so that the retaining member 80 can be more firmly fixed to the elastic body portion 70 with the retaining portion 82 pressing the support member 30 and the conductive member 20 against the retaining surface 77 of the cover portion 74.

[0089] In the conductive sealing device 6, similarly to the conductive member 20 and the support member 30 in the above-described conductive structure 1, the pressing side surface 31 of the support member 30 contacts the pressed side surface 22 of the conductive member 20, and the support member 30 supports the conductive member 20. As a result, in the conductive sealing device 6 as well, the contact side surface 21 at the inner peripheral end portion 25 of the conductive member 20 contacts the outer peripheral surface of the shaft to which it is applied.

[0090] Each component of the conductive sealing device 6 has the configuration described above, and is assembled into an assembled state to form the conductive sealing device 6 as shown in Fig. 10. In the conductive sealing device 6, the fitting portion 81 of the holding member 80 is fitted into the outer peripheral end portion 74a of the cover portion 74 of the elastic body portion 70, and the overlapping conductive member 20 and supporting member 30 are sandwiched between the holding portion 82 of the holding member 80 and the cover portion 74 of the elastic body portion 70. In this way, the holding member 80 is fixed to the elastic body portion 70, and the conductive member 20 and supporting member 30 are fixed between the holding member 80 and the elastic body portion 70.

[0091] FIG. 11 is a conceptual diagram showing an example of an application target of the conductive sealing device 6. FIG. 12 is a cross-sectional view showing an example of a state in which the conductive sealing device 6 is used in the application target shown in FIG. 11. As an example, the conductive sealing device 6 is applied to a drive unit 200 of a battery electric vehicle (BEV) as shown in FIG. 11. The drive unit 200 has a configuration similar to the above-described drive unit 100 (see FIGS. 5 and 6), but differs in that the conductive structure 1 is not attached to the drive unit 100. Furthermore, the conductive sealing device 6 is attached to the drive unit 200 instead of the oil seal 127 of the drive unit 100. As an example, the conductive sealing device 6 is provided between the housing 120 and the shaft 122 of the reducer 102 and is in use. Specifically, the gasket portion 73 of the elastic body portion 70 is fitted into the axial hole 126 of the housing 120, the conductive sealing device 6 is fixed to the axial hole 126, and the shaft 122 is inserted into the seal lip 71, conductive member 20, and support member 30, thereby placing the conductive sealing device 6 in an operating state. In the operating state, the seal lip 71 contacts the outer peripheral surface 122a of the shaft 122, sealing the object to be sealed. In the operating state, the conductive member 20 is supported by the support member 30, and the contact side surface 21 at the inner peripheral end portion 25 of the conductive member 20 contacts the outer peripheral surface 122a of the shaft 122. In addition, the holding member 80 that holds the conductive member 20 is made of a conductive metal and contacts the inner peripheral surface 126a of the axial hole 126 of the housing 120. In this way, the conductive member 20 and the holding member 80 form a conductive path that allows electricity to flow between the shaft 122 and the housing 120 in the operating state.

[0092] The drive unit 200 described above is an example of an application of the conductive sealed device 6, and the application of the conductive sealed device 6 is not limited thereto. The conductive sealed device 6 is used, for example, in drive units for battery electric vehicles (BEVs), hybrid vehicles (HVs), fuel cell vehicles (FCVs), and other electric vehicles (EVs). In vehicles equipped with electric motors, such as electric vehicles (EVs), electromagnetic noise can be generated by induced currents generated by the motor. Electromagnetic noise can also be generated by the on / off operation of an inverter for controlling the current supplied to an electric motor, or by the induced voltage of the electric motor itself. As described above, the conductive sealed device 6 forms a conductive path and directs electromagnetic noise transmitted to the shafts 110 and 122 to the housing 120. This prevents communication failures and malfunctions in electronic devices and electrolytic corrosion in metal components, such as bearings.

[0093] The conductive structure 7 of the conductive sealing device 6 is used in the same manner as the conductive structure 1 described above, and acts in the same manner as the conductive structure 1, and provides the same effects.

[0094] The conductive structure 7 may have a conductive member 40 and a support member 50 instead of the conductive member 20 and the support member 30. That is, the conductive structure 7 may have a divided body 4 and a gap 3 instead of the conductive member 20 and the support member 30. In this case, the protrusion 5 accommodated in the gap 3 is provided on the side surface 82b of the holding portion 82 of the holding member 80. The protrusion 5 may be provided on the holding surface 77 of the cover portion 74 of the elastic body portion 70, instead of the side surface 82b of the holding portion 82 of the holding member 80. The protrusion 5 may also be provided on the holding surface 77 of the cover portion 74 of the elastic body portion 70, in addition to the side surface 82b of the holding portion 82 of the holding member 80. One or more protrusions 5 may be provided.

[0095] As with the conductive structure 1, the conductive structure 7 of the conductive sealing device 6 can also be modified in various ways.

[0096] Although the present invention has been described above through the above embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0097] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. Furthermore, the above-described embodiments do not limit the scope of the present invention, and the present invention may include any and all applications. The components of the above-described embodiments, as well as their arrangement, materials, conditions, shape, size, etc., are not limited to those illustrated and may be modified as appropriate. For example, the present invention includes differences that arise during implementation due to manufacturing tolerances, etc. Furthermore, components illustrated in different embodiments may be partially substituted or combined within the scope of technical inconsistency. Furthermore, the various configurations may be selectively combined as appropriate to achieve at least some of the above-described problems and effects.

[0098] For example, the shape of the outer peripheral edge 20b of the conductive member 20 may not be a circular shape, but may have a straight line portion. For example, the shape of the outer peripheral edge 20b of the conductive member 20 may be rectangular. The conductive members 20, 40 and the support members 30, 50 may be bonded together using an adhesive. The conductive members 20, 40 and the holding members 10, 80 or the elastic body portion 70 may be bonded together using an adhesive. In this case, the adhesive is applied so as not to cause resistance in the conductive path. In this case, a conductive adhesive is used. [Explanation of symbols]

[0099] 1,2,7 Conductive structure, 3,3A,3B gap, 4,4A,4B,4C dividing body, 4a,4b,4Aa,4Ab,4Ba,4Bb end, 5a,5b convex part, 6 conductive sealing device, 10 holding member, 11 inner holding member, 12 fitting part, 12a outer peripheral surface, 13 holding part, 15 Outer holding member, 16 fitting part, 16a inner peripheral surface, 17 holding part, 17a side surface, 18 holding part, 20,40 conductive member, 20A,20B,20C conductive member piece, 20Ac,20Ad,20Bc,20Bd end, 20a,20Aa,20Ba inner peripheral end, 20b,20Ab,20Bb Outer edge, 21, 21A, 21B Contact side surface, 22, 22A, 22B pressed side surface, 23 metal wire, 24 through hole, 25, 25A, 25B inner peripheral end portion, 26, 26A, 26B outer peripheral end portion, 30, 50 support member, 30A, 30B, 30C support member piece, 30Ac, 30Ad, 30Bc, 30Bd end portion, 30a, 30Aa, 30Bb inner peripheral end portion, 30b, 30Ab, 30Bb outer peripheral end portion, 31, 31A, 31B pressing side surface, 32, 32A, 32B back surface, 33, 33A, 33B inner peripheral end portion, 34, 34A, 34B outer peripheral end portion, 35 protrusion portion, 60 reinforcing ring, 61 cylindrical portion, 62 annular portion, 70 elastic body portion, 71 seal lip, 71a convex portion, 72 Base portion, 73 gasket portion, 73a outer peripheral surface, 74 cover portion, 74a outer peripheral end portion, 75 fitting surface, 76 recess, 77 holding surface, 77a recess, 80 holding member, 81 fitting portion, 81a outer peripheral surface, 81b inner peripheral surface, 81c end portion, 82 holding portion, 82a, 82b side surface, 83 convex portion, 100, 200 drive device, 101 electric motor, 102 reducer, 103 inverter, 104 battery, 105 wheel, 110, 122 shaft, 110a, 122a outer peripheral surface, 111, 120 housing, 121 reduction gear stage, 112, 123 bearing, 113, 124, 126 shaft hole, 113a, 124a, 126a inner peripheral surface, 125, 127 Oil seal, x-axis

Claims

1. a holding member that is an annular conductive member around an axis; a conductive member that is a member formed of a metal material annularly around the axis; a support member that is a member formed from an annular elastic material around the axis, the conductive member and the support member are overlapped in the axial direction and held by the holding member, the conductive member has an annular inner peripheral end portion around the axis, the support member overlaps the conductive member so as to be able to press the inner peripheral side end of the conductive member toward the inner peripheral side. Conductive structure.

2. the conductive member has a contact side surface and a pressed side surface, which are a pair of annular surfaces facing back to back in the axial direction, the support member has a pressing side surface and a back surface, which are a pair of annular surfaces facing back to back with respect to the axial direction, The pressed side surface of the conductive member and the pressing side surface of the support member face each other. The conductive structure of claim 1 .

3. the conductive member has a plurality of through holes, the support member extends into the plurality of through holes of the conductive member; The conductive structure according to claim 1 or 2.

4. the conductive member has a mesh structure that forms the plurality of through holes; The conductive structure of claim 3 .

5. At least a part of the portion of the support member that enters the plurality of through holes protrudes from the through holes. The conductive structure of claim 3 .

6. The conductive member is more flexible than the support member. The conductive structure of claim 1 .

7. the conductive member and the support member that are stacked together have at least one gap extending in a radial direction and at least one divided body extending around the axis, The divided body has a pair of ends in a direction around the axis, The gap is continuous with the end of the divided body. The conductive structure of claim 1 .

8. the conductive member has one divided body and one gap, the pair of ends of the divided body are opposed to each other in a direction around the axis, the gap is a gap between the opposing ends of the divider; The conductive structure of claim 7 .

9. the conductive member has two divided bodies and two gaps, one of the pair of ends of one of the divided bodies and one of the pair of ends of the other of the divided bodies face each other in a direction around the axis, the other of the pair of ends of one of the divided bodies faces the other of the pair of ends of the other of the divided bodies in a direction around the axis, one of the gaps is formed between the one end of the one divided body and the one end of the other divided body, the other of the gaps is formed between the other end of the one divided body and the other end of the other divided body. The conductive structure of claim 7 .

10. the conductive member and the support member are held by the holding member at their outer peripheries; The conductive structure of claim 1 .

11. The support member is made of PTFE or PEEK. The conductive structure of claim 1 .

12. 1. A conductive sealing device for sealing between a shaft and a hole through which the shaft passes, comprising: a reinforcing ring that is an annular member around the axis; an elastic body portion formed of an annular elastic body around the axis and attached to the reinforcing ring; a conductive structure annular about the axis, the elastic body portion has a seal lip that contacts the shaft, the conductive structure includes a holding member which is a conductive member annular about the axis, a conductive member which is a member formed of a metal material annular about the axis, and a support member which is a member formed of an elastic material annular about the axis, the conductive member and the support member are overlapped in the axial direction and held by the holding member, the conductive member has an annular inner peripheral end portion around the axis, the support member overlaps the conductive member so as to be able to press the inner peripheral end of the conductive member against the shaft; Conductive sealing device.

13. the conductive member has a contact side surface and a pressed side surface, which are a pair of annular surfaces facing back to back in the axial direction, the support member has a pressing side surface and a back surface, which are a pair of annular surfaces facing back to back with respect to the axial direction, The pressed side surface of the conductive member and the pressing side surface of the support member face each other.

13. The conductive sealing device of claim 12.

14. the conductive member has a plurality of through holes, the support member extends into the plurality of through holes of the conductive member; 14. The conductive sealing device of claim 12 or 13.

15. the conductive member has a mesh structure that forms the plurality of through holes; 15. The conductive sealing device of claim 14.

16. At least a part of the portion of the support member that enters the plurality of through holes protrudes from the through holes.

15. The conductive sealing device of claim 14.

17. The conductive member is more flexible than the support member.

13. The conductive sealing device of claim 12.

18. the conductive member and the support member that are stacked together have at least one gap extending in a radial direction and at least one divided body extending around the axis, The divided body has a pair of ends in a direction around the axis, The gap is continuous with the end of the divided body.

13. The conductive sealing device of claim 12.

19. the conductive member has one divided body and one gap, the pair of ends of the divided body are opposed to each other in a direction around the axis, the gap is a gap between the opposing ends of the divider; 20. The conductive structure of claim 18.

20. the conductive member has two divided bodies and two gaps, one of the pair of ends of one of the divided bodies and one of the pair of ends of the other of the divided bodies face each other in a direction around the axis, the other of the pair of ends of one of the divided bodies faces the other of the pair of ends of the other of the divided bodies in a direction around the axis, one of the gaps is formed between the one end of the one divided body and the one end of the other divided body, the other of the gaps is formed between the other end of the one divided body and the other end of the other divided body.

20. The conductive sealing device of claim 18.

21. the conductive member and the support member are held by the holding member at their outer peripheries; 13. The conductive sealing device of claim 12.

22. The support member is made of PTFE or PEEK.

13. The conductive sealing device of claim 12.

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