Connection structure

Abstract

To provide a technology that can improve the sealing performance of a connection structure for electrically connecting conductive members to each other.SOLUTION: A connection structure includes a conductive connecting member and a sealing structure that seals the inside of the connecting member, and a pair of slits are formed in the connecting member between a crimping portion and the sealing structure, one of the pair of slits is formed on one side of the connecting member in the crimping direction of the crimping portion, and the other of the pair of slits is formed on the other side of the connecting member in the crimping direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a connection structure for conductive members. [Background technology]

[0002] Conventionally, an electrical connection method using a bus bar has been common as a means for electrically connecting a vehicle's electronically controlled automatic transmission with a control unit, etc. For example, Patent Document 1 discloses an electrical connection structure in which a spring function component is provided between a base-end extension and a tip-end extension of a bus bar. Meanwhile, Patent Document 2 discloses a technology for improving the waterproofing of an electrical connection structure using a connector by injecting a photocurable resin into gaps that should be waterproofed to seal the gaps. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3488998 [Patent Document 2] Patent No. 2650547 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, a connection structure for electrically connecting equipment that is subject to fluid pressure, such as hydraulic equipment or water hydraulic equipment, to other equipment is required to prevent fluid leakage into or out of the equipment. In particular, a connection structure with higher sealing performance is desired for application to equipment that generates vibrations during operation.

[0005] The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a technique capable of improving sealing performance in a connection structure for electrically connecting conductive members to each other. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention employs the following means. That is, the gist of the present invention is as follows. [1] A connection structure for electrically connecting conductive members, a conductive connection member having a first connection portion formed at one end in the axial direction and capable of connecting a first conductive member, a second connection portion formed at the other end in the axial direction and capable of connecting a second conductive member, and a separation portion formed between the first connection portion and the second connection portion and separating the first conductive member and the second conductive member therein; a seal structure that is disposed in the spaced portion to seal the inside of the connection member; Equipped with At least one of the first connection portion and the second connection portion is formed at an axial end portion of the connection member as a sleeve-shaped crimping portion that is connected to the conductive member by crimping, a pair of slits is formed between the crimping portion and the seal structure in the connection member, one of the pair of slits is formed on one side surface of the connection member in the crimping direction of the crimping portion, The other of the pair of slits is formed on the other side surface of the connection member in the crimping direction. Connection structure. [2] The distance in the axial direction between the tip of the crimping portion and the seal structure is L1, The height of the crimping portion in the crimping direction before crimping is defined as H1, The depth of one of the pair of slits in the crimping direction is S1, When the depth of the other of the pair of slits in the crimping direction is S2, L1≧H1×0.75 and 0.35≦(S1+S2) / H1≦0.67, The connection structure described in [1]. [3] the sealing structure is formed by an elastic body fitted into the spaced portion. The connection structure according to [1] or [2]. [4] the sealing structure is formed integrally with the connecting member as a partition wall that closes the separation portion, The connection structure according to [1] or [2]. [5] the sealing structure is formed by a resin molding filled in the spaced apart portion. The connection structure according to [1] or [2]. [6] Further, a peripheral seal member is provided on the outer periphery of the connecting member, The outer periphery seal member seals the outer periphery of the connection member by continuously covering at least a part of the outer periphery of the connection member in the axial direction. A connection structure according to any one of [1] to [5]. [7] The connecting member is arranged so as to be subjected to a pressure action of a fluid on at least one end side in an axial direction. A connection structure according to any one of [1] to [6]. [8] The pair of slits are formed spaced apart from each other in the axial direction. A connection structure according to any one of [1] to [7]. [Effects of the Invention]

[0007] According to the present invention, it is possible to improve the sealing performance in a connection structure for electrically connecting conductive members to each other. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an overall perspective view of a connection structure according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the connection structure according to the embodiment. [Figure 3] FIG. 3 is a side view showing the state before the crimping process of the connection member according to the embodiment. [Figure 4] FIG. 4 is a top view showing the state of the connection member according to the embodiment before crimping. [Figure 5]FIG. 5 is a side view schematically showing a state in which a lead wire is crimped to a connection member according to an embodiment. [Figure 6] FIG. 6 is a cross-sectional view of the separation portion before and after the crimping process of the connection member according to the embodiment. [Figure 7] FIG. 7 is a side view showing a state before crimping of a connection member according to a first modified example of the embodiment. [Figure 8] FIG. 8 is a cross-sectional view of a connection structure according to the second modification of the embodiment. [Figure 9] FIG. 9 is a cross-sectional view of a connection structure according to a third modification of the embodiment. [Figure 10] FIG. 10 is a diagram showing the simulation results of the first embodiment. [Figure 11] FIG. 11 is a diagram showing the simulation results of Comparative Example 4. In FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Specific embodiments of the present invention will be described below with reference to the drawings. The dimensions, materials, shapes, and relative positions of the components described in the following embodiments are not intended to limit the technical scope of the present invention unless otherwise specified.

[0010] One embodiment of the present invention is a connection structure for electrically connecting conductive members. Specifically, the connection structure is attached to a device that is subject to fluid pressure, and electrically connects a first cable (conductive member) provided inside the device with a second cable (conductive member) provided outside the device. The connection structure includes a conductive connection member having a sleeve-shaped at least one of its axial ends, a seal structure disposed within the connection member, and an outer circumferential seal member. That is, the connection member may have a sleeve-shaped connection portion at both axial ends, or may have a sleeve-shaped connection portion at only one end. The connection member is formed in a cylindrical shape and has a first connection portion at one longitudinal end to which a first cable can be connected, a second connection portion at the other longitudinal end to which a second cable can be connected, and a separation portion between the first and second connection portions that separates the first and second cables. The connection member is inserted into a mounting hole that penetrates the device from the inside to the outside. The seal structure is disposed in the separation portion of the connection member to seal the interior of the connection member. The outer periphery seal member is disposed so as to cover the outer periphery of the connection member, thereby sealing the outer periphery of the connection member.

[0011] Here, the "fluid" is not limited to a liquid, but may also be a gas. Furthermore, "fluid pressure" may include pressure acting from inside the device (internal pressure) and pressure acting from outside the device (external pressure). The connection structure according to the present invention can be applied to devices on which fluid pressure acts, but the device to which the connection structure is attached is not particularly limited. Examples of devices to which the connection structure is applied include hydraulic devices that operate using hydraulic pressure and water hydraulic devices that operate using water pressure. Furthermore, the device to which the connection structure is applied may be, for example, a liquid-cooled electric motor (rotating electric machine) in which cooling water or oil is supplied into the motor casing. Furthermore, the "second conductive member" may be a cable provided in a device (another device) different from the device to which the connection structure is applied, or a cable provided in the device to which the connection structure is applied.

[0012] [Overall configuration] Hereinafter, as an embodiment, a description will be given of a connection structure according to the present invention applied to an electric motor. Fig. 1 is an overall perspective view of a connection structure 100 according to the embodiment. Fig. 2 is a cross-sectional view of the connection structure 100 according to the embodiment. Figs. 1 and 2 show a state in which lead wires 10, 20 are crimped to a connection member 1 and are electrically connected.

[0013] 2, the connection structure 100 is attached to the motor 200. More specifically, the connection structure 100 is attached to a case 200a that is a housing of the motor 200.

[0014] The motor 200 is a three-phase motor used as a driving power source for, for example, hybrid vehicles, electric vehicles, etc. In FIG. 2, the symbol IS indicates the internal space of the case 200a (i.e., the interior of the motor 200), and the symbol ES indicates the external space of the case 200a (i.e., the exterior of the motor 200). The internal space IS of the case 200a accommodates a stator, coils, a rotor, a shaft, etc. The motor 200 is liquid-cooled, and cooling oil is supplied to the internal space IS of the case 200a. Therefore, the pressure of the cooling oil acts on the motor 200 from the internal space IS side. As shown in FIG. 2, the case 200a is formed with an attachment opening 200b for attaching the connection structure 100. The attachment opening 200b penetrates from the inside to the outside of the case 200a.

[0015] The motor 200 also has three lead wires that are used to input three-phase AC to the coils. The motor 200 has three lead wires 10 (an example of a "first conductive member" according to the present invention). The three lead wires 10 are arranged in the internal space IS of the case 200a (i.e., inside the motor 200), and each lead wire 10 corresponds to a coil of each phase. The lead wire 10 also has a conductive wire 101 made of a conductive material, and an insulating tube 102 made of an electrically insulating material and covering the conductive wire 101. The tip of the conductive wire 101 is exposed from the insulating tube 102, thereby forming the tip of the lead wire 10.

[0016] Furthermore, three lead wires 20 (an example of a "second conductive member" according to the present invention) connected to an inverter, which is an external device (other device) of the motor 200, are arranged in the external space ES of the case 200a (i.e., outside the motor 200). The lead wires 20 are cables that are electrically connected to the lead wires 10 of the motor 200, thereby supplying AC current generated by the inverter to the lead wires 10 of the motor 200. Each of the three lead wires 20 corresponds to a respective lead wire 10. The lead wires 20 include a conductive wire 201 made of a conductive material and an insulating tube 202 made of an electrically insulating material and covering the conductive wire 201. The tip of the conductive wire 201 is exposed from the insulating tube 202, thereby forming the tip of the lead wire 20.

[0017] In this embodiment, the conductive wire 101 of the lead wire 10 and the conductive wire 201 of the lead wire 20 are formed as twisted wires in which a plurality of metallic (e.g., copper) linear conductors are bundled and twisted together. However, the present invention is not limited to this. The first conductive member and the second conductive member according to the present invention may be formed as twisted wires or as a single wire (single-core) consisting of a single linear conductor. Furthermore, the first conductive member and the second conductive member are not limited to electric wires (lead wires) as long as they are capable of transmitting electricity. The first conductive member and the second conductive member may be, for example, a bus bar, or may be an electric wire with a terminal-shaped conductor provided at the tip. Furthermore, the number of the first conductive member and the second conductive member may or may not be multiple.

[0018] A connection structure 100 according to this embodiment is configured to electrically connect a lead wire 10 provided inside a motor 200 to a lead wire 20 provided outside the motor 200, and to seal the inside and outside of the motor 200. As shown in Fig. 2, the connection structure 100 includes a connection member 1, a seal structure 2, a holder 3, a multiple grommet 4 (an example of an "outer peripheral seal member" according to the present invention), a gasket 5, and a bolt 6. Each component of the connection structure 100 will be described below.

[0019] [Holder, gasket, bolt] The holder 3 is a member that holds the connection member 1 and is attached to the mounting opening 200b of the motor 200. The holder 3 is made of an electrically insulating material and has electrical insulation properties. The material of the holder 3 is not particularly limited, but examples thereof include a resin material such as PPS (polyphenylene sulfide). The holder 3 has a fitting portion 31 and a plate portion 32. The fitting portion 31 is formed in a cylindrical shape and fits into the mounting opening 200b. The plate portion 32 is formed in a plate shape that is perpendicular to the axial direction of the fitting portion 31 and is provided at the end of the fitting portion 31 on the external space ES side. The plate portion 32 has a closing portion 32a that closes the end of the fitting portion 31 and a fixing portion 32b that protrudes outward beyond the fitting portion 31. The fixing portion 32b abuts against the surface of the case 200a on the external space ES side and is fixed to the case 200a with bolts 6. The holder 3 is formed with a recess 3a, which is a space surrounded by the fitting portion 31 and the closing portion 32a. The recess 3a is recessed relative to the internal space IS of the case 200a. A multiple grommet 4 is attached to the recess 3a. The closing portion 32a is also formed with a mounting hole 3b into which the connecting member 1 is inserted. The mounting hole 3b is connected to the recess 3a and penetrates the inside and outside of the case 200a (i.e., the inside and outside of the motor 200). In this embodiment, the mounting hole 3b is attached to the holder 3 attached to the case 200a of the motor 200. Although the holder 3 has an attachment hole 3b formed therein, the present invention is not limited to this. The holder 3 is not an essential component of the present invention, and the connecting member according to the present invention may be inserted into, for example, an attachment hole formed in the housing of the device.

[0020] The gasket 5 is made of an elastic material and is attached to the outer periphery of the fitting portion 31 of the holder 3 to seal between the outer periphery of the fitting portion 31 and the inner wall surface of the attachment opening 200b. The material of the gasket 5 is not particularly limited, but examples include rubber such as ACM (acrylic rubber), resin materials, etc. The gasket 5 may also be made of metal.

[0021] The bolt 6 is a fastening member that fastens the fixing portion 32b of the holder 3 to the case 200a, thereby fixing the connection structure 100 to the motor 200.

[0022] [Connection parts] The connection member 1 is formed in a cylindrical shape, and is configured as a crimp terminal to which an electric wire can be crimped at both ends. In other words, the connection member 1 is configured as a crimp sleeve. The connection member 1 is inserted into a mounting hole 3b that penetrates the inside and outside of the motor 200. Here, with respect to the connection member 1, the direction in which the central axis A1 of the connection member 1 extends (i.e., the extension direction of the connection member 1) is defined as the "axial direction," the radial direction of the connection member 1 is defined as the "radial direction," and the direction around the axis of the connection member 1 is defined as the "circumferential direction." Both ends of the connection member 1 are crimped by plastic deformation so as to be crushed by pressure from the outside in the radial direction. Note that although the connection member 1 according to this embodiment is formed in a cylindrical shape, it may also be in a rectangular cylindrical shape. The connection member 1 is arranged so that at least one axial end side is subjected to the pressure action of a fluid.

[0023] The connecting member 1 can crimp the lead wires 10, 20 to each end by crimping the conductive wires 101, 201 of the lead wires 10, 20 inserted into each end. The connecting member 1 is made of metal and is conductive. Therefore, the conductive wires 101 and 201 are electrically connected via the connecting member 1, and the lead wires 10 and 20 are electrically connected. Examples of materials for the connecting member 1 include metal materials such as copper, aluminum, and silver. The material of the connecting member according to the present invention is not particularly limited, and may be any material that is conductive and can be crimped. The connecting member according to the present invention does not need to be entirely conductive, as long as at least a portion of it is conductive. For example, the connecting member may be a metal tubular member whose outer periphery is coated with a resin material.

[0024] The connection structure 100 according to this embodiment includes three connection members 1, corresponding to the number of combinations of lead wires 10 and 20 to be connected to each other. However, the number of connection members according to the present invention is not limited to a multiple number. The number of connection members can be changed as appropriate depending on the number of pairs of first conductive members and second conductive members to be connected.

[0025] 2, the connection member 1 has a sleeve-shaped first connection portion 11 at one end in the axial direction, a sleeve-shaped second connection portion 12 at the other end in the axial direction, and a hollow separation portion 13 between the first connection portion 11 and the second connection portion 12. The connection member 1 is inserted into the mounting hole 3b of the holder 3 so that the first connection portion 11 is located in the internal space IS of the case 200a, the second connection portion 12 is located in the external space ES of the case 200a, and the separation portion 13 is located in the mounting hole 3b of the holder 3.

[0026] The first connecting portion 11 and the second connecting portion 12 according to this embodiment are both formed in a sleeve-like shape having a hollow structure, and are formed at the axial end of the connecting member 1 as crimping portions that can be connected to a conductive member by crimping. However, the present invention is not limited to this, and it is sufficient that at least one of the first connecting portion and the second connecting portion is a sleeve-shaped crimping portion. In other words, it is sufficient that at least one of the axial end portions of the connecting member is a sleeve-shaped crimping portion. For example, One of the first connecting portion 11 and the second connecting portion 12 may be configured as a sleeve-shaped crimping portion, and the other may not be formed in a sleeve shape but may be configured so that a conductive member such as a bus bar can be connected to the end opposite the sleeve by screwing or the like. Hereinafter, when the first connecting portion 11 and the second connecting portion 12 are described without distinguishing between them, they will be simply referred to as "crimping portion."

[0027] The first connection portion 11 is formed by one end portion of the connection member 1, and is capable of connecting the lead wire 10. When the first connection portion 11 is crimped with the conductive wire 101, which is the tip portion of the lead wire 10, inserted into the first connection portion 11, the lead wire 10 is crimped to the first connection portion 11.

[0028] The second connection part 12 is formed by the other end part of the connection member 1, and is capable of connecting a lead wire 20. With the conductive wire 201, which is the tip part of the lead wire 20, inserted into the second connection part 12, the second connection part 12 is crimped, whereby the lead wire 20 is crimped to the second connection part 12.

[0029] As shown in FIG. 2, the lead wires 10 and 20 are crimped to the connection member 1 while being spaced apart from each other inside the connection member 1.

[0030] The separation portion 13 is formed hollow at a portion between both ends of the connection member 1. By interposing the separation portion 13 between the first connection portion 11 and the second connection portion 12, the lead wires 10 and 20 are separated from each other, creating a non-contact state. The separation portion 13 is sealed internally by disposing a seal structure 2 therein. The separation portion 13 is also sealed at its outer periphery by being covered by a multiple grommet 4. Note that, in this embodiment, the separation portion 13 is formed at the central position of the connection member 1 in the axial direction, but the present invention is not limited thereto. The position of the separation portion 13 does not have to be the central position of the connection member 1 in the axial direction.

[0031] Here, the radial direction of the connection member 1 and the direction in which the crimping portions (first connection portion 11 and second connection portion 12) are pressed for crimping is referred to as the "crimping direction." In the connection member 1 according to this embodiment, the crimping direction of the first connection portion 11 and the crimping direction of the second connection portion 12 are the same. However, the crimping directions of the first connection portion 11 and the second connection portion 12 may be different. The crimping process causes the crimping portions (first connection portion 11 and second connection portion 12) to be crushed and plastically deformed in the crimping direction, whereby the conductive wire 101 of the lead wire 10 is crimped to the first connection portion 11, and the conductive wire 201 of the lead wire 20 is crimped to the second connection portion 12.

[0032] Fig. 3 is a side view showing the state of the connecting member 1 according to the embodiment before crimping. Fig. 3 shows the state of the connecting member 1 before plastic deformation by crimping, as viewed in a direction perpendicular to the crimping direction and the axial direction. Fig. 3 also shows the state in which the seal structure 2 is disposed in the separation portion 13.

[0033] As shown in FIG. 3 , a pair of slits 14, 14 are formed in the connection member 1. The slits 14 are notches that penetrate the connection member 1 from the inside to the outside. The pair of slits 14, 14 are formed between the first connection portion 11 and the separation portion 13 in the connection member 1. That is, the pair of slits 14, 14 are formed between the crimping portion and the seal structure 2. The pair of slits 14, 14 are formed at positions opposite each other in the crimping direction. Specifically, one of the pair of slits 14, 14 is formed on one side surface of the connection member 1 in the crimping direction, and the other of the pair of slits 14, 14 is formed on the other side surface of the connection member 1 in the crimping direction (the surface opposite to the one side surface). In the connection member 1 according to this embodiment, the pair of slits 14, 14 are formed at the same position in the axial direction of the connection member 1. However, the present invention is not limited to this. The pair of slits 14, 14 may be formed at different positions in the axial direction of the connection member 1, as in Modification 1 described below.

[0034] In this embodiment, a pair of slits 14, 15 are provided between the first connecting portion 11 and the seal structure 2. In the present embodiment, slits 14 are formed between the crimped portion and the seal structure 2, but the pair of slits 14, 14 may be formed between the second connection portion 12 and the seal structure 2. That is, in the present invention, the pair of slits may be formed between the crimped portion and the seal structure of at least one of the first connection portion and the second connection portion, and may be formed in only one of the first connection portion and the second connection portion, or in both. For example, a pair of slits 14, 14 may be formed both between the first connection portion 11 and the seal structure 2 and between the second connection portion 12 and the seal structure 2. Note that in this embodiment, only a pair of slits 14, 14 are formed between the crimped portion and the seal structure 2, and no other slits are formed, but the present invention is not limited to this. In the present invention, a slit other than the pair of slits may be formed between the crimped portion and the seal structure in the connection member.

[0035] Hereinafter, when describing the pair of slits 14, 14 formed in the connecting member 1 according to the embodiment, one slit 14 will be referred to as the "first slit 14a" and the other slit 14 will be referred to as the "second slit 14b", and when describing the pair without distinction, they will simply be referred to as the "slit 14".

[0036] FIG. 4 is a top view showing a state of the connecting member 1 according to the embodiment before crimping. FIG. 4 illustrates the connecting member 1, in which the seal structure 2 is arranged in the separation portion 13, viewed along the crimping direction. As shown in FIG. 4, the slit 14 is formed linearly and extends in a direction substantially perpendicular to the crimping direction and the axial direction. When viewed in the crimping direction, the slit 14 extends across the central axis A1 of the connecting member 1 and is formed axially symmetrical with respect to the central axis A1. The slit 14 separates the first connecting portion 11 and the separation portion 13. In other words, the first connecting portion 11 and the separation portion 13 are arranged on opposite sides of the slit 14.

[0037] As shown in FIG. 3, the depth of the first slit 14a in the crimping direction is defined as S1, and the depth of the second slit 14b in the crimping direction is defined as S2. Here, the "depth of the slit 14" specifically refers to the distance from the opening of the slit 14 to the end when the connecting member 1 is viewed in a direction perpendicular to the crimping direction and the axial direction. The depth S1 of the first slit 14a and the depth S2 of the second slit 14b may be equal to or different from each other. Also, as shown in FIG. 3, the width of the first slit 14a in the axial direction of the connecting member 1 is defined as T1, and the width of the second slit 14b is defined as T2. The width T1 of the first slit 14a and the width T2 of the second slit 14b may be equal to or different from each other.

[0038] The shape of the slit according to the present invention is not limited to a linear shape. The slit according to the present invention may be an elliptical shape whose major axis is substantially perpendicular to the axial direction of the connecting member, or a polygonal shape whose longitudinal direction is substantially perpendicular to the axial direction of the connecting member. Examples of polygonal shapes include a triangular shape, a rectangular shape, and a diamond shape. Furthermore, the inclination angle of the slit relative to the axial direction of the connecting member is not limited to approximately 90°. The slit may be inclined relative to the axial and radial directions.

[0039] FIG. 5 is a side view schematically illustrating a state in which a lead wire 10 is crimped to a connection member 1 according to an embodiment. The figure illustrates a state in which a seal structure 2 is disposed in a separation portion 13. Here, a region of the crimped portion adjacent to the slit 14 in the axial direction is referred to as a "slit-adjacent region," and is represented by a dot pattern in FIGS. 3 to 5. In this embodiment, a slit-adjacent region 11a adjacent to the first slit 14a and a slit-adjacent region 11b adjacent to the second slit 14b are formed in the first connection portion 11. The slit-adjacent regions 11a and 11b are adjacent to the slit 14, and are therefore more susceptible to deformation than other portions of the connection member 1. Therefore, when the first connection portion 11 is pressurized in the crimping direction during crimping of the connection member 1, the slit-adjacent regions 11a and 11b undergo plastic deformation preferentially over the separation portion 13, as shown in FIG. 5.

[0040] Here, since spaced portion 13 is a portion whose periphery is sealed by multiple grommet 4 as described below, from the viewpoint of improving the adhesion between spaced portion 13 and multiple grommet 4 and improving the sealing performance of the periphery, it is preferable to suppress plastic deformation of spaced portion 13 as much as possible during the crimping process of connecting member 1. If the amount of deformation of spaced portion 13 due to the plastic deformation of the crimped portion is large, it is necessary to increase the axial length of spaced portion 13 and seal the periphery at a position sufficiently distant from the crimped portion (i.e., a position where the amount of deformation of spaced portion 13 is small) in order to ensure sealing performance of the periphery.

[0041] FIG. 6 is a cross-sectional view of the separation portion 13 of the connection member 1 according to the embodiment before and after crimping. FIG. 6 illustrates a cross-section of the separation portion 13 before and after the lead wires 10 and 20 are crimped to the connection member 1. The cross-section illustrated in FIG. 6 is perpendicular to the axial direction. In the example illustrated in FIG. 6, the separation portion 13 is crushed in the crimping direction and deformed into an ellipse due to the plastic deformation of the crimped portion during the crimping process. Here, DB denotes the outer diameter of the separation portion 13 before the crimping process, and DA denotes the minor axis (outer diameter in the transverse direction) of the elliptical separation portion 13 after the crimping process. The difference between DB and DA is the amount of deformation DX. That is, DX = DB - DA. In this case, from the viewpoint of improving the sealing performance of the outer periphery, DX is preferably 0.085 mm or less. That is, the connection member 1 is preferably configured so that DX≦0.085 mm. By keeping DX of the separation portion 13 at 0.085 mm or less, it is possible to improve the sealing performance of the outer periphery of the separation portion 13. Furthermore, the axial length of the separation portion 13 is sufficient as long as it is long enough to ensure the space in which the seal structure 2 can be arranged, and it is not necessary to make it large in consideration of plastic deformation of the separation portion 13. This allows the length of the separation portion 13 to be set short, thereby realizing space-saving and cost-saving of the connecting member 1.

[0042] As shown in FIG. 3 , the axial distance between the seal structure 2 and the tip of the crimped portion, where a pair of slits 14, 14 are formed between the crimped portion and the seal structure 2, is defined as L1. Specifically, L1 is the axial distance from the axially most distal point (i.e., the point farthest from the seal structure 2) of the crimped portion, where a pair of slits 14 are formed between the crimped portion and the seal structure 2, to the point of the seal structure 2 closest to the crimped portion. In this embodiment, L1 corresponds to the axial distance between the tip of the first connecting portion 11 and the seal structure 2. Furthermore, H1 corresponds to the height in the crimping direction before crimping (before plastic deformation) of the crimped portion, where a pair of slits 14, 14 are formed between the crimped portion and the seal structure 2. In this embodiment, H1 corresponds to the height in the crimping direction of the first connecting portion 11 before crimping. In this case, the connection structure 100 according to this embodiment is configured so that L1≧H1×0.75 and 0.35≦(S1+S2) / H1≦0.67.

[0043] Furthermore, the connecting member 1 may be set so that the thickness of the separated portion 13 is greater than the thickness of the crimped portion. By forming the separated portion 13 thicker than the crimped portion, the crimped portion can be made more easily deformed than the separated portion 13. As a result, in the crimping process of the connecting member 1, the first connecting portion 11 and the second connecting portion 12 undergo plastic deformation preferentially over the separated portion 13, and therefore plastic deformation of the separated portion 13 can be suppressed.

[0044] [Seal structure] As shown in FIG. 2 , the seal structure 2 according to this embodiment is a spherical plug made of an elastic material, and is disposed in the separation portion 13 to seal the interior of the connecting member 1. The seal structure 2 is made of rubber, such as ACM (acrylic rubber), and is elastically deformable. The seal structure 2 is fitted into the separation portion 13 while being compressed in the radial direction of the connecting member 1. The restoring force of the seal structure 2 brings the surface of the seal structure 2 into contact with the inner surface of the separation portion 13 without any gaps, thereby closing the separation portion 13 and sealing the interior of the connecting member 1. This prevents the fluid from passing through the interior of the connection member 1 and leaking out.

[0045] The shape of the seal structure according to the present invention is not limited to a sphere. The seal structure may be cylindrical or a truncated cone with a tapered periphery, and may have elastically deformable protrusions or irregularities formed on the periphery. The periphery may also be chamfered. The material of the seal structure is not limited to rubber. Examples of materials for the seal structure include, but are not limited to, elastic materials such as rubber, cured materials such as resin materials and adhesives, and metal materials. The seal structure may also be a resin molded body integrally molded with the connecting member by resin insert molding, as in Variation 2 described below. The seal structure according to the present invention does not need to be electrically insulating and may be conductive as long as it can seal the interior of the connecting member. Forming the seal structure from a conductive material allows current to flow not only through the connecting member but also through the seal structure, thereby improving the electrical conductivity of the entire connection structure. When the seal structure is formed from a conductive material, it is preferable that the seal structure be disposed so as to contact both the first and second conductive members. This allows current to flow more easily between the first and second conductive members via the seal structure, further improving electrical conductivity. When the seal structure is made of metal, the seal structure may be a metal partition plate that is arranged perpendicular to the axial direction and divides the internal space of the connecting member in the axial direction, and is fixed to the connecting member by brazing, for example. While the seal structure 2 is configured as a separate component from the connecting member 1 in this embodiment, the seal structure according to the present invention may also be configured as an integral component with the connecting member. In other words, the seal structure may be part of the connecting member. In this case, the seal structure may be formed as a metal partition wall that is arranged substantially perpendicular to the axial direction and divides the internal space of the connecting member 1 in the axial direction, as in Modification 1 described below.

[0046] [Multiple Grommets] As shown in Fig. 2, the multiple grommet 4 is formed in a plate shape from an elastic and electrically insulating material, and is disposed in the recess 3a of the holder 3 so as to cover the outer periphery of the connection member 1, thereby sealing the outer periphery of the connection member 1. More specifically, the multiple grommet 4 continuously covers the outer periphery of a portion of the connection member 1 in the axial direction, including the separation portion 13. However, in the present invention, the portion of the connection member 1 that is covered by the outer periphery seal member is not particularly limited. The outer periphery seal member according to the present invention may be one that continuously covers at least a portion of the outer periphery of the connection member in the axial direction, but is not limited thereto.

[0047] The multiple grommet 4 has a through hole 4a formed therein that extends along the axial direction of the connecting member 1. The connecting member 1 is inserted into the through hole 4a. In this embodiment, three through holes 4a are formed, corresponding to the number of connecting members 1. As a result, the multiple grommet 4 has a structure in which multiple grommets (three in this example) are integrated. The material of the multiple grommet 4 is not particularly limited, but examples include rubber such as ACM (acrylic rubber) and resin materials.

[0048] A protrusion 41 is formed on the outer periphery of the multiple grommet 4, and a protrusion 42 is formed on the inner wall of the through hole 4a. The protrusions 41, 42 are formed as annular protrusions that are continuous in the circumferential direction and are elastically deformable. The multiple grommet 4 is fitted into the recess 3a of the holder 3 with the protrusion 41 crushed and compressed. The restoring force of the protrusion 41 brings the outer surface of the multiple grommet 4 into contact with the inner surface of the recess 3a without any gaps, thereby sealing the gap between the multiple grommet 4 and the holder 3. The connecting member 1 is inserted into the through hole 4a so as to crush and compress the protrusion 42. The restoring force of the protrusion 42 brings the outer surface of the connecting member 1 into contact with the inner wall surface of the through hole 4a without any gaps, thereby sealing the gap between the connecting member 1 and the multiple grommet 4. In this way, the multiple grommet 4 seals the gap between the connecting member 1 and the holder 3. As a result, the outer periphery of the connecting member 1 is sealed. This allows the fluid to Leakage through the outer periphery of the material 1 is prevented.

[0049] In this embodiment, a multiple grommet 4, in which multiple grommets are integrated, is used as the peripheral seal member, but the peripheral seal member according to the present invention is not limited to this. The peripheral seal member may be a single grommet or a single O-ring that seals the periphery of each connecting member. Furthermore, as long as electrical insulation between multiple connecting members is ensured, the peripheral seal member according to the present invention does not need to be electrically insulating and may be conductive. Furthermore, the peripheral seal member may be a resin molded body integrally molded with the connecting members and holder by resin insert molding.

[0050] [Actions and Effects] As described above, the connection structure 100 according to this embodiment is attached to the motor 200, which is subjected to fluid pressure, and electrically connects the lead wire 10 provided inside the motor 200 with the lead wire 20 provided outside the motor 200. The connection structure 100 includes a conductive connection member 1 and a seal structure 2 that seals the interior of the connection member 1. The connection member 1 has a first connection portion 11 formed at one end in the axial direction and to which the lead wire 10 can be connected, a second connection portion 12 formed at the other end in the axial direction and to which the lead wire 20 can be connected, and a separation portion 13 formed between the first connection portion 11 and the second connection portion 12 and that separates the lead wire 10 and the lead wire 20 inside the connection member 1. The seal structure 2 is disposed in the separation portion 13 to seal the interior of the connection member 1.

[0051] The connection structure 100 configured as described above can electrically connect the lead wire 10 and the lead wire 20 by connecting the lead wire 10 to the first connection portion 11 and the lead wire 20 to the second connection portion 12. Furthermore, by disposing the seal structure 2 in the separation portion 13 and sealing the interior of the connection member 1, it is possible to prevent fluid from passing through the interior of the connection member 1 and leaking. In this embodiment, the conductive wire 101 of the lead wire 10 and the conductive wire 201 of the lead wire 20 are formed as twisted wires. This may allow oil to penetrate into the interior of the lead wires 10 and 20 due to capillary action. However, because the lead wires 10 and 20 are isolated from each other by the seal structure 2 within the connection member 1, it is also possible to prevent oil from leaking through the interior of the lead wires 10 and 20. As described above, this embodiment can prevent oil from leaking from the internal space IS of the motor 200 through the interior of the connection member 1 and into the external space ES of the motor 200. As a result, this embodiment can improve the sealing performance of the connection structure 100.

[0052] Furthermore, the connection structure 100 according to this embodiment employs a simple structure in which a sealing member is disposed inside the connection member 1, and is therefore relatively inexpensive, and can provide a reliable seal even when applied to equipment that generates vibrations during operation, such as the motor 200. As a result, the connection structure 100 according to this embodiment can reliably achieve improved sealing performance with a relatively inexpensive structure.

[0053] In this embodiment, at least one of the first connection portion 11 and the second connection portion 12 is formed as a crimping portion that is connected to a conductive member by crimping at an axial end of the connection member 1. Thus, by forming at least one of the first connection portion 11 and the second connection portion 12 as a crimping portion with a relatively simple structure, conductive members can be electrically connected to each other with a relatively inexpensive structure.

[0054] Furthermore, in the connection structure 100 according to this embodiment, a pair of slits 14, 14 are formed between the crimped portion of the connection member 1 and the seal structure 2. By forming the slits 14 between the crimped portion and the seal structure 2, it is possible to reduce the influence of plastic deformation of the crimped portion on the separated portion 13. Therefore, the separation portion 13 during the crimping process of the connection member 1 can be easily formed. This can suppress plastic deformation.

[0055] Here, if the slit 14 is formed on only one of the two side surfaces of the crimped portion in the crimping direction, that side surface may be crushed preferentially over the other side surface, potentially resulting in distortion of the separation portion 13. In response to this, one of the pair of slits 14, 14 is formed on one side surface of the connecting member 1 in the crimping direction, and the other is formed on the other side surface of the connecting member 1 in the crimping direction. That is, the slit 14 is formed on both side surfaces of the crimped portion in the crimping direction. This allows the crimped portion to be crushed approximately evenly from both sides in the crimping direction, thereby offsetting distortion of the separation portion 13. As a result, plastic deformation of the separation portion 13 during crimping of the connecting member 1 can be further suppressed. In particular, when the conductive members to be connected are not stranded electric wires but metal members such as bus bars or single-core conductors, the shape of the crimped portion may be symmetrical or approximately symmetrical in the crimping direction. According to the connection structure 100 of this embodiment, even when connecting such conductive members, the amount of deformation of the separation portion 13 can be kept small.

[0056] Here, to further minimize the deformation of the separation portion 13, the slit 14 needs to be formed deeper. On the other hand, the deeper the slit 14, the smaller the cross-sectional area of ​​the connection member 1 at the location where the slit 14 is formed, making it difficult to ensure the conductive performance of the connection member 1. In contrast, in this embodiment, L1 ≧ H1 × 0.75 and 0.35 ≦ (S1 + S2) / H1 ≦ 0.67 are satisfied. By satisfying L1 ≧ H1 × 0.75 and 0.35 ≦ S1 / H1, the influence of plastic deformation of the crimped portion on the separation portion 13 can be further reduced, and plastic deformation of the separation portion 13 can be suitably suppressed. This allows the deformation amount DX of the separation portion 13 to be suppressed to 0.085 mm or less. As a result, the sealing performance of the outer periphery of the separation portion 13 can be further improved. Furthermore, by making (S1+S2) / H1≦0.67, it is possible to ensure the cross-sectional area of ​​the connection member 1 at the portion where the slit 14 is formed, and to ensure the conductive performance of the connection member 1. From the viewpoint of space saving, it is preferable to make L1≦H1×6, and it is more preferable to make L1≦H1×4. This makes it possible to prevent the connection member 1 from becoming large, and to achieve space saving.

[0057] Furthermore, the seal structure 2 according to this embodiment is formed by an elastic body fitted into the spaced portion 13. This allows the inside of the connection member 1 to be sealed reliably.

[0058] The connection structure 100 according to this embodiment also includes a multiple grommet 4 disposed on the outer periphery of the connection member 1. The multiple grommet 4 seals the outer periphery of the connection member 1 by continuously covering at least a portion of the outer periphery of the connection member 1 in the axial direction. Thus, sealing the outer periphery of the connection member 1 with the multiple grommet 4 prevents fluid from passing through the outer periphery of the connection member 1 and leaking out. In other words, oil in the internal space IS of the motor 200 is prevented from passing through the outer periphery of the connection member 1 and leaking into the external space ES of the motor 200. In this way, the connection structure 100 according to this embodiment can seal the interior of the connection member 1 with the seal structure 2 and seal the outer periphery of the connection member 1 with the multiple grommet 4. As a result, while electrically connecting the inside and outside of the motor 200, it is possible to prevent oil in the internal space IS of the motor 200 from leaking into the external space ES of the motor 200. Note that the peripheral seal member is not a required component of the present invention.

[0059] [Variations] Modified examples of the connection structure according to the present embodiment will be described below. In the following description of the modified examples, differences from the connection structure described using Figures 1 to 6 will be mainly described, and the same components as those in the above-described connection structure will be assigned the same reference numerals and detailed description will be omitted.

[0060] [Variation 1] Fig. 7 is a side view showing a state before crimping of a connecting member 1A according to Modification 1 of the embodiment. Fig. 7 shows a state in which the connecting member 1A before plastic deformation by crimping is viewed in a direction perpendicular to the crimping direction and the axial direction. Fig. 7 also shows a state in which the seal structure 2 is disposed in the separation portion 13.

[0061] As shown in FIG. 7 , in the connection member 1A according to the first modification, a pair of slits 14, 14 are formed between the crimped portion and the seal structure 2 and spaced apart from each other in the axial direction of the connection member 1A. That is, in the first modification, the slits 14 formed on both side surfaces of the crimped portion in the crimping direction are spaced apart from each other in the axial direction. According to the first modification, by forming the pair of slits 14, 14 between the crimped portion and the seal structure 2 and spaced apart from each other in the axial direction, the cross-sectional area of ​​the connection member 1A at the location where the slits 14 are formed can be increased while minimizing the amount of deformation of the spaced portion 13. That is, the electrical conductivity of the connection member 1A can be increased while suppressing plastic deformation of the spaced portion 13, thereby improving the sealing performance of the outer periphery of the spaced portion 13. Here, as shown in FIG. 7 , the axial distance between the crimped portion-side ends of the pair of slits 14, 14 is denoted as Ts. More specifically, Ts is the distance in the axial direction between the end of the first slit 14a on the crimping portion side and the end of the second slit 14b on the crimping portion side.

[0062] [Variation 2] Fig. 8 is a cross-sectional view of a connection structure 100B according to a second modification of the embodiment. As shown in Fig. 8, the connection structure 100B according to the second modification differs from the above-described connection structure 100 in that the seal structure 2B is formed by a part of the connection member 1B. The seal structure 2B according to the second modification is formed integrally with the connection member 1B as a metal partition wall that closes the separation portion 13. The seal structure 2B is disposed approximately perpendicular to the axial direction, and the internal space of the connection member 1B is divided in the axial direction by the seal structure 2B. According to the second modification, the interior of the connection member 1B can be reliably sealed.

[0063] [Variation 3] FIG. 9 is a cross-sectional view of a connection structure 100C according to a third modification of the embodiment. As shown in FIG. 9, the connection structure 100C according to the third modification differs from the connection structure 100 described above in that the seal structure 2C is formed of a resin molded body filled in the separation portion 13. The seal structure 2C according to the third modification is integrally molded with the connection member 1 by, for example, resin insert molding. The resin molded body forming the seal structure 2C may be a molded body of a thermoplastic resin or a cured product of a thermosetting resin such as an adhesive. As shown in FIG. 9, the seal structure 2C may be filled into the first connection portion 11 and the second connection portion 12 to fix the conductive wires 101, 201 of the lead wires 10, 20. According to the third modification, the interior of the connection member 1 can be reliably sealed.

[0064] [Simulation Test] The deformation of the connecting member according to the present embodiment when subjected to crimping was simulated by CAE analysis. A leakage test was also conducted on the connecting structure. The present invention is not limited to the following examples.

[0065] As Examples 1 to 8, analytical models corresponding to the connection structure 100 including the above-mentioned connection member 1 were created. As Examples 9 to 13, analytical models corresponding to the connection structure including the connection member 1A according to the above-mentioned modified example 1 were created. Examples 1 to 13 satisfy the conditional expressions of L1≧H1×0.75 and 0.35≦(S1+S2) / H1≦0.67. As Comparative Examples 1 and 2, analytical models corresponding to the connection structure in which a pair of slits 14, 14 is formed in the connection member but does not satisfy the above-mentioned conditional expressions were created. As Comparative Examples 3 and 4, analytical models corresponding to the connection structure in which only one slit 14 (only the first slit 14a) is formed in the connection member were created. As Comparative Example 5, an analytical model was created that corresponds to a connection structure in which no slit 14 is formed in the connection member. As Comparative Example 6, an analytical model was created that corresponds to a connection structure in which a pair of slits 14, 14 is formed in the connection member but no seal member is disposed. Table 1 shows the conditions, deformation simulation results, and leakage test results for Examples 1 to 13 and Comparative Examples 1 to 6. Note that "h1" in Table 1 is the seal length, which represents half the axial length of the seal structure (see FIG. 3). [Table 1]

[0066] In the simulation, pressure was applied to the analytical model from the crimping direction, simulating the crimping process for crimping the lead wire, and the deformation amount DX at each part of the analytical model was analyzed. The material of the analytical model was copper. The pressure applied to the crimped part was set to the pressure expected when crimping using an appropriate crimping tool that matches the dimensions of the connecting member.

[0067] Fig. 10 is a diagram showing the simulation results of Example 1. Fig. 11 is a diagram showing the simulation results of Comparative Example 4. Figs. 10(A) and 11(A) are side views of the analytical model. Figs. 10(B) and 11(B) are cross-sectional views perpendicular to the axial direction at the crimped portion of the analytical model. The gradation scale shown in Figs. 10 and 11 represents the amount of deformation.

[0068] By comparing Examples 1 to 13 and Comparative Examples 1 to 6 shown in Table 1, it was found that by forming a pair of slits 14, 14 between the crimped portion and the seal structure and satisfying the conditional expressions L1≧H1×0.75 and 0.35≦(S1+S2) / H1≦0.67, the deformation amount DX can be kept to 0.085 or less.

[0069] In the leakage test, the connection structures shown in Figures 1 and 2 were actually fabricated for Examples 1 to 3, 9 to 11 and Comparative Examples 1 to 6, and a fluid leakage test was conducted under specified conditions. In the leakage test, the presence or absence of fluid leakage was confirmed for each of the interior and outer periphery of the connection member. If no fluid leakage occurred, the result was judged as "Good," and if fluid leakage was observed, the result was judged as "Poor." As shown in Table 1, in Examples 1 to 3, 9 to 11, no liquid leakage occurred inside or on the outer periphery of the connection member. In Comparative Examples 1 to 4, no fluid leakage occurred inside the connection member, but fluid leakage occurred on the outer periphery. In Comparative Examples 5 and 6, liquid leakage occurred inside and on the outer periphery of the connection member. This demonstrates that the sealing performance of the connection structure can be improved by limiting the deformation amount DX to 0.085 mm or less.

[0070] <Other> Although the embodiments of the connection structure according to the present invention have been described above, each aspect disclosed in this specification can be combined with any other feature disclosed in this specification. [Explanation of symbols]

[0071] 1. Connection member 2. Seal structure 3. Holder 4. Multiple grommet (an example of a peripheral seal member) 5. Gasket 6 bolts 10, 20... Lead wire (an example of the first conductive member and the second conductive member) 11 First connection part 12 Second connection part 13... Separation part 14. Slit 100 Connection structure

Claims

1. A connection structure for electrically connecting conductive members, a conductive connection member having a first connection portion formed at one end in the axial direction and capable of connecting a first conductive member, a second connection portion formed at the other end in the axial direction and capable of connecting a second conductive member, and a separation portion formed between the first connection portion and the second connection portion and separating the first conductive member and the second conductive member therein; a seal structure that is disposed in the spaced portion to seal the inside of the connection member; Equipped with At least one of the first connection portion and the second connection portion is formed at an axial end portion of the connection member as a sleeve-shaped crimping portion that is connected to the conductive member by crimping, a pair of slits is formed between the crimping portion and the seal structure in the connection member, one of the pair of slits is formed on one side surface of the connection member in the crimping direction of the crimping portion, The other of the pair of slits is formed on the other side surface of the connection member in the crimping direction. Connection structure.

2. The distance in the axial direction between the tip of the crimping portion and the seal structure is L1, The height of the crimping portion in the crimping direction before crimping is defined as H1, The depth of one of the pair of slits in the crimping direction is defined as S1, When the depth of the other of the pair of slits in the crimping direction is S2, L1≧H1×0.75 and 0.35≦(S1+S2) / H1≦0.67; The connection structure according to claim 1 .

3. the sealing structure is formed by an elastic body fitted into the spaced portion. The connection structure according to claim 1 or 2.

4. the sealing structure is formed integrally with the connecting member as a partition wall that closes the separation portion, The connection structure according to claim 1 or 2.

5. the sealing structure is formed by a resin molding filled in the spaced apart portion. The connection structure according to claim 1 or 2.

6. Further, a peripheral seal member is provided on the outer periphery of the connecting member, The outer periphery seal member seals the outer periphery of the connection member by continuously covering at least a part of the outer periphery of the connection member in the axial direction. The connection structure according to claim 1 or 2.

7. The connecting member is arranged so as to be subjected to a pressure action of a fluid on at least one end side in an axial direction. The connection structure according to claim 1 or 2.

8. The pair of slits are formed spaced apart from each other in the axial direction. The connection structure according to claim 1 or 2.

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