Connection structure

Abstract

To provide a technique capable of improving sealing performance in a connection structure for electrically connecting conductive members.SOLUTION: A connection structure includes: a connection member which has conductivity and in which at least one of both ends in an axial direction is in a sleeve shape; and a sealing structure which is arranged in the connection member. The connection member has: a first connection part that is formed on one end side and is connectable to a first conductive member; a second connection part that is formed on the other side and is connectable to a second conductive member; and a separation part that is formed between the first connection part and the second connection part and separates the first conductive member and the second conductive member in the inside of the connection member. The sealing structure is arranged at the separation part to seal inside of the connection member.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a connection structure of conductive members.

Background Art

[0002] Conventionally, as a means for electrically connecting an electronically controlled automatic transmission of a vehicle and a control unit or the like, an electrical connection method using a bus bar has been common. For example, Patent Document 1 discloses a structure of an electrical connection portion provided with a spring function component between a base end side extension portion and a tip end side extension portion of a bus bar. On the other hand, Patent Document 2 discloses a technique for sealing a gap portion to be waterproof by injecting a photocurable resin into the gap portion to enhance the waterproof property of an electrical connection structure using a connector.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, in a connection structure for electrically connecting a device to which a fluid pressure such as a hydraulic device or a water pressure device acts and another device, it is required to prevent leakage of the fluid to the inside and outside of the device. In particular, in order to apply to a device that generates vibration during operation, a connection structure with higher sealing performance is desired.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a technique capable of improving sealing performance in a connection structure for electrically connecting conductive members.

Means for Solving the Problems

[0006] In order to solve the above problems, the connection structure according to the present invention adopts the following configuration. That is, the gist of the present invention is as follows. 〔1〕 A connection structure for electrically connecting conductive members, comprising a connection member having conductivity and at least one of both axial ends in a sleeve shape, and a seal structure disposed inside the connection member. The connection member has a first connection portion formed at one end side and connectable to the first conductive member, a second connection portion formed at the other end side and connectable to the 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 inside the connection member. The seal structure seals the inside of the connection member by being disposed in the separation portion. Connection structure. 〔2〕 At least one of the first connection portion and the second connection portion is formed at an axial end of the connection member as a crimping portion connected to the conductive member by crimping. The connection structure according to 〔1〕. 〔3〕 Let the axial distance between the tip of the crimping portion and the seal structure be L1, When the height of the crimping portion before crimping in the crimping direction is H1, L1≧H1×0.88. The connection structure according to 〔2〕. 〔4〕 A slit is formed in the connection member between the crimping portion and the seal structure. The connection structure according to 〔2〕. 〔5〕 Let the axial distance between the tip of the crimping portion and the seal structure be L2, When the height of the crimping portion before crimping in the crimping direction is H2, and the depth of the slit in the crimping direction is S1, L2≧H2×0.68 and 0.25≦S1 / H2≦0.67. The connection structure according to [4]. [6] The sealing structure is formed by an elastic body fitted into the separation part. The connection structure according to any one of [1] to [5]. [7] The sealing structure is integrally formed with the connection member as a partition wall that closes the separation part. The connection structure according to any one of [1] to [5]. [8] The sealing structure is formed by a resin molded body filled in the separation part. The connection structure according to any one of [1] to [5]. [9] The connection member further includes an outer peripheral seal member disposed on the outer periphery thereof. The outer peripheral 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 in the circumferential direction. The connection structure according to any one of [1] to [8].

[10] The connection member is arranged so as to receive the pressure action of the fluid at at least one end side in the axial direction. The connection structure according to any one of [1] to [9].

Effect of the Invention

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

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

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Figure 10

Figure 11

DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments are not intended to limit the technical scope of the present invention only to these 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 on which the pressure of a fluid acts, and electrically connects a first cable (conductive member) provided inside the device and a second cable (conductive member) provided outside the device. The connection structure has conductivity and includes at least one of the axial ends being a sleeve-shaped connection member, a seal structure disposed within the connection member, and an outer peripheral seal member. That is, the connection member may have sleeve-shaped connection portions 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, has a first connection portion capable of connecting the first cable on one end side in the longitudinal direction, has a second connection portion capable of connecting the second cable on the other end side in the longitudinal direction, and has a separation portion for separating the first cable and the second cable between the first connection portion and the second connection portion. The connection member is inserted into a mounting hole penetrating inside and outside the device. The seal structure is disposed in the separation portion of the connection member to seal the inside of the connection member. The outer peripheral seal member is disposed to cover the outer periphery of the connection member to seal the outer periphery of the connection member.

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

[0012] [Overall Configuration] Hereinafter, as an embodiment, an aspect in which the connection structure according to the present invention is applied to an electric motor will be described. FIG. 1 is an overall perspective view of a connection structure 100 according to an embodiment. FIG. 2 is a cross-sectional view of the connection structure 100 according to the embodiment. In FIGS. 1 and 2, lead wires 10 and 20 are crimped to a connection member 1, and a state in which they are electrically connected is illustrated.

[0013] As shown in FIG. 2, the connection structure 100 is attached to a motor 200. More specifically, the connection structure 100 is attached to a case 200a which is a housing of the motor 200.

[0014] The motor 200 is, for example, a three-phase motor used as a driving power source for a hybrid vehicle, an electric vehicle, or the like. In FIG. 2, reference numeral IS indicates an internal space of the case 200a (that is, the inside of the motor 200), and reference numeral ES indicates an external space of the case 200a (that is, the outside of the motor 200). In the internal space IS of the case 200a, a stator (stator), a coil, a rotor (rotor), a shaft, and the like are accommodated. Further, 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. Further, as shown in FIG. 2, an attachment opening 200b for attaching the connection structure 100 is formed in the case 200a. The attachment opening 200b penetrates the inside and outside of the case 200a.

[0015] Further, the motor 200 has three lead wires 10 (an example of the "first conductive member" according to the present invention), which are cables for inputting three-phase alternating current to the coil. The three lead wires 10 are arranged in the internal space IS of the case 200a (that is, the inside of the motor 200), and each corresponds to the coil of each phase. Further, the lead wire 10 has a conductive wire 101 formed of a conductive material and an insulating tube 102 formed of an electrical insulating material and covering the conductive wire 101. The tip of the conductive wire 101 is exposed from the insulating tube 102 to constitute the tip of the lead wire 10.

[0016] Further, in the external space ES of the case 200a (i.e., outside the motor 200), three lead wires 20 (an example of the "second conductive member" according to the present invention), which are external devices (other devices) of the motor 200 and are connected to an inverter, are arranged. The lead wires 20 are cables that supply the alternating current generated by the inverter to the lead wires 10 of the motor 200 by being electrically connected to the lead wires 10 of the motor 200. Each of the three lead wires 20 corresponds to each lead wire 10. The lead wire 20 has a conductive wire 201 formed of a conductive material and an insulating tube 202 formed of an electrical insulating material and covering the conductive wire 201. The tip of the conductive wire 201 is exposed from the insulating tube 202 to constitute the tip of the lead wire 20.

[0017] In the present embodiment, the conductive wire 101 of the lead wire 10 and the conductive wire 201 of the lead wire 20 are formed as stranded wires in which a plurality of metal (for example, copper) linear conductors are bundled and twisted together. However, the present invention is not limited thereto. The first conductive member and the second conductive member according to the present invention may be formed of a stranded wire or may be formed of a single wire (single core) composed of one linear conductor. Further, the first conductive member and the second conductive member may be any that can transmit electricity and are not limited to electric wires (lead wires). The first conductive member and the second conductive member may be, for example, bus bars or may be those in which a terminal-shaped conductor is provided at the tip of an electric wire. Also, the number of the first conductive member and the second conductive member may be plural or may not be plural.

[0018] The connection structure 100 according to the present embodiment is configured to electrically connect the lead wire 10 provided inside the motor 200 and the lead wire 20 provided outside the motor 200 and to be able 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 multi-piece grommet 4 (an example of the "outer peripheral seal member" according to the present invention), a gasket 5, and a bolt 6. Hereinafter, each component of the connection structure 100 will be described.

[0019] [Holder, gasket, bolt] The holder 3 is a member that holds the connecting member 1 and is attached to the mounting opening 200b of the motor 200. The holder 3 is formed of an electrically insulating material and has electrical insulation properties. The material of the holder 3 is not particularly limited, and examples thereof include resin materials 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 orthogonal to the axial direction of the fitting portion 31 and is provided at the end portion of the fitting portion 31 on the external space ES side. The plate portion 32 has a closing portion 32a that closes the end portion of the fitting portion 31 and a fixing portion 32b that protrudes outward from 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 by a bolt 6. A recess 3a, which is a space surrounded by the fitting portion 31 and the closing portion 32a, is formed in the holder 3. The recess 3a is recessed with respect to the internal space IS of the case 200a. A multi-piece grommet 4 is mounted in the recess 3a. Also, the closing portion 32a is 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 (that is, the inside and outside of the motor 200).

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

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

[0022] [Connecting member] The connecting member 1 is formed in a cylindrical shape, and is configured as crimp terminals capable of crimping electric wires at both ends thereof. That is, the connecting member 1 is configured as a crimp sleeve. The connecting member 1 is inserted into the mounting hole 3b that penetrates inside and outside the motor 200. Here, regarding the connecting member 1, the direction in which the central axis A1 of the connecting member 1 extends (that is, the extending direction of the connecting member 1) is defined as the "axial direction", the radial direction of the connecting member 1 is defined as the "radial direction", and the direction around the axis of the connecting member 1 is defined as the "circumferential direction". Both ends of the connecting member 1 are crimped by being plastically deformed so as to be crushed by pressure from the outside in the radial direction. Note that the connecting member 1 according to the present embodiment is formed in a cylindrical shape, but may be formed in a rectangular tube shape. The connecting member 1 is arranged so as to receive the pressure action of the fluid on at least one end side in the axial direction.

[0023] The connecting member 1 can crimp the lead wires 10 and 20 at both ends by being crimped in a state where the conductive wires 101 and 201 of the lead wires 10 and 20 are inserted into both ends. The connecting member 1 is made of metal and has conductivity. Therefore, the conductive wire 101 and the conductive wire 201 are electrically connected through the connecting member 1, and the lead wire 10 and the lead wire 20 are electrically connected. Examples of the material of the connecting member 1 include metal materials such as copper, aluminum, and silver. Note that the material of the connecting member according to the present invention is not particularly limited as long as it has conductivity and can be crimped. Note that the connecting member according to the present invention does not necessarily have conductivity throughout, and it is sufficient that at least a part thereof has conductivity. For example, it may be a cylindrical member made of metal whose outer periphery is coated with a resin material.

[0024] The connection structure 100 according to the present embodiment includes three connecting members 1 corresponding to the number of combinations of the lead wire 10 and the lead wire 20 that are connected to each other. However, the number of connecting members according to the present invention is not limited to a plurality. The number of connecting members can be appropriately changed according to the number of pairs of the first conductive member and the second conductive member to be connected.

[0025] As shown in FIG. 2, the connection member 1 has a sleeve-shaped first connection portion 11 on one end side in the axial direction, a sleeve-shaped second connection portion 12 on the other end side 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 such 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] Both the first connection portion 11 and the second connection portion 12 according to the present embodiment are formed in a sleeve shape having a hollow structure, and are formed at the axial end of the connection member 1 as a crimping portion which is a portion connected to the conductive member by crimping. However, the present invention is not limited to this, and at least one of the first connection portion and the second connection portion may be in a sleeve shape. That is, the connection member only needs to have at least one of the axial both ends in a sleeve shape. Further, in the present invention, at least one of the first connection portion and the second connection portion may be formed as a crimping portion, and it is not necessary for both the first connection portion and the second connection portion to be crimping portions. For example, one of the first connection portion and the second connection portion may be configured as a sleeve-shaped crimping portion, and the other may be formed in a non-sleeve shape and configured to be connectable to a conductive member such as a bus bar by screwing or the like at the end opposite to the sleeve. Hereinafter, when the first connection portion 11 and the second connection portion 12 are described without distinction, they will simply be referred to as "crimping portion".

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

[0028] The second connection portion 12 is formed by the other end of the connection member 1 and can connect the lead wire 20. The lead wire 20 is crimped to the second connection portion 12 by crimping the second connection portion 12 with the conductive wire 201, which is the tip of the lead wire 20, inserted into the second connection portion 12.

[0029] As shown in FIG. 2, the lead wire 10 and the lead wire 20 are crimped to the connection member 1 in a state of being separated from each other inside the connection member 1.

[0030] The separation portion 13 is formed in a hollow shape by a portion between both end portions of the connection member 1. By the separation portion 13 being interposed between the first connection portion 11 and the second connection portion 12, the lead wire 10 and the lead wire 20 are separated from each other, and a non-contact state is formed. The inside of the separation portion 13 is sealed by arranging the seal structure 2. Further, the outer periphery of the separation portion 13 is sealed by being covered with the multi-piece grommet 4. In the present 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 to this. The position of the separation portion 13 may not be the central position in the axial direction of the connection member 1.

[0031] Here, the direction in the radial direction of the connection member 1 in which the crimping portions (the first connection portion 11 and the second connection portion 12) are pressurized for crimping is referred to as the "crimping direction". Also, the crimping direction of the first connection portion 11 is referred to as the "first crimping direction", and the crimping direction of the second connection portion 12 is referred to as the "second crimping direction". In the connection member 1 according to the present embodiment, the first crimping direction and the second crimping direction coincide with each other. However, as in the modification example 2 described later, the first crimping direction and the second crimping direction may be different.

[0032] FIG. 3 is a side view showing a state before the crimping process of the connection member 1 according to the embodiment. In FIG. 3, a state is shown in which the connection member 1 before being plastically deformed by the crimping process is visually recognized along a direction orthogonal to the first crimping direction (the second crimping direction) and the axial direction. FIG. 4 is a side view schematically showing a state in which the lead wires 10 and 20 are crimped to the connection member 1 according to the embodiment. In FIGS. 3 and 4, a state in which the seal structure 2 is arranged in the separation portion 13 is shown. As shown in FIG. 4, by the crimping process, the crimping portions (the first connection portion 11 and the second connection portion 12) are pressed and crushed in the crimping direction and plastically deformed, so that 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.

[0033] Here, since separated portion 13 is a portion whose outer periphery is sealed by multiple grommet 4 as described below, from the viewpoint of improving the adhesion between separated portion 13 and multiple grommet 4 and improving the sealing performance of the outer periphery, it is preferable to suppress plastic deformation of separated portion 13 as much as possible during the crimping process of connecting member 1. When the amount of deformation of separated portion 13 due to the influence of plastic deformation of the crimped portion is large, it is necessary to increase the axial length of separated portion 13 and seal the outer periphery at a position sufficiently away from the crimped portion (i.e., a position where the amount of deformation of separated portion 13 is small) in order to ensure the sealing performance of the outer periphery.

[0034] 5 is a cross-sectional view of the separated portion 13 before and after the crimping process of the connection member 1 according to the embodiment. In FIG. 5, the cross-section of the separated portion 13 before the lead wires 10 and 20 are crimped to the connection member 1 and the connection 5 shows a cross section of the spaced portion 13 after the lead wires 10 and 20 are crimped to the member 1. The cross section shown in FIG. 5 is a cross section perpendicular to the axial direction. In the example shown in FIG. 5, the spaced portion 13 is crushed in the crimping direction due to the influence of plastic deformation of the crimped portion in the crimping process, and is deformed into an ellipse. Here, the outer diameter of the spaced portion 13 before the crimping process is DB, and the short diameter (outer diameter in the short direction) of the spaced portion 13 deformed into an ellipse after the crimping process is DA. Then, the deformation amount which is the difference between DB and DA is DX. That is, DX=DB-DA. At this time, from the viewpoint of improving the sealing performance of the outer periphery, DX is preferably 0.085 [mm] or less. That is, it is preferable that the connection member 1 is configured so that DX≦0.085 [mm]. By suppressing the DX of the spaced portion 13 to 0.085 [mm] or less, the sealing performance of the outer periphery in the spaced portion 13 can be improved. Furthermore, the axial length of the separated portion 13 is sufficient as long as it is possible to secure a space in which the seal structure 2 can be disposed, and does not need to be large in consideration of plastic deformation of the separated portion 13. This allows the length of the separated portion 13 to be set short, thereby realizing space saving and cost reduction of the connection member 1.

[0035] As shown in FIG. 3, between the crimping portion and the spaced portion 13 in the connecting member 1 (that is, between the crimping portion and the seal structure 2), a slit 14 (see FIG. 6) is not formed as in the first modification described later, and the connecting member 1 is continuous in the axial direction and the circumferential direction. At this time, the distance in the axial direction between the tip of the crimping portion and the seal structure 2 is defined as L1. Specifically, L1 is the distance in the axial direction from the point at the foremost end in the axial direction in the crimping portion (that is, the point farthest from the seal structure 2) to the point closest to the crimping portion in the seal structure 2. Also, the height of the crimping portion before crimping (before plastic deformation) in the crimping direction is defined as H1. At this time, it is preferable that L1 ≧ H1 × 0.88. By doing so, the influence of the plastic deformation of the crimping portion on the spaced portion 13 can be reduced, and the plastic deformation of the spaced portion 13 can be suppressed. As a result, the amount of deformation DX of the spaced portion 13 can be suppressed to 0.085 [mm] or less. As a result, the sealing performance of the outer periphery in the spaced portion 13 can be further improved. Further, from the viewpoint of space saving, it is preferable that L1 ≦ H1 × 6, and more preferably L1 ≦ H1 × 4. By doing so, an increase in the size of the connecting member 1 can be suppressed, and space saving can be achieved.

[0036] Also, the thickness (radial thickness) of the connecting member 1 in the first connecting portion 11 is defined as T1, the thickness of the connecting member 1 in the second connecting portion 12 is defined as T2, and the thickness of the connecting member 1 in the spaced portion 13 is defined as T3. At this time, it may be set such that T1 < T3 and T2 < T3. That is, the thickness of the spaced portion 13 may be set to be larger than the thickness of the crimping portion. By forming the spaced portion 13 thicker than the crimping portion, the crimping portion can be made more easily deformed than the spaced portion 13. As a result, in the crimping process of the connecting member 1, since the first connecting portion 11 and the second connecting portion 12 are plastically deformed preferentially over the spaced portion 13, the plastic deformation of the spaced portion 13 can be suppressed.

[0037] [Seal structure] As shown in Fig. 2, the seal structure 2 according to this embodiment is a spherical plug formed of an elastic material, and is arranged in the separation part 13 to seal the inside of the connection member 1. The seal structure 2 is made of rubber such as ACM (acrylic rubber) for example, and is elastically deformable. The seal structure 2 is fitted inside the separation part 13 in a state compressed in the radial direction of the connection member 1. Due to the restoring force of the seal structure 2, the surface of the seal structure 2 and the inner peripheral surface of the separation part 13 are in contact without a gap, so that the separation part 13 is in a closed state and the inside of the connection member 1 is sealed. Thereby, it is possible to prevent fluid from passing through and leaking inside the connection member 1.

[0038] Note that the shape of the seal structure according to the present invention is not limited to a sphere. The seal structure may be a cylinder, or may be a frustum of a cone having a taper formed on the outer periphery, and elastic deformable protrusions or irregularities may be formed on the outer periphery. Further, its periphery may be chamfered. Further, the material of the seal structure is not limited to rubber. Examples of the material of the seal structure include, in addition to elastic bodies such as rubber, cured products such as resin materials and adhesives, and metal materials, etc., The present invention is not limited to these. The seal structure may be, for example, a resin molded body integrally formed with the connecting member by resin insert molding as in Modification Example 4 described later. Further, as long as the inside of the connecting member can be sealed, the seal structure according to the present invention does not necessarily have to have electrical insulation and may have conductivity. By forming the seal structure from a conductive material, current can flow not only through the connecting member but also through the seal structure, so that the conductive performance of the entire connection structure can be improved. Further, when the seal structure is formed of a conductive material, it is preferable that the seal structure is arranged so as to be in contact with both the first conductive member and the second conductive member. Thereby, current easily flows between the first conductive member and the second conductive member through the seal structure, and the conductive performance is further improved. When the seal structure is made of metal, the seal structure may be, for example, a metal partition plate that is arranged orthogonally to the axial direction and partitions the internal space of the connecting member in the axial direction, and is fixed to the connecting member by brazing or the like. Further, in the present embodiment, the seal structure is configured as a seal structure 2 that is a separate part from the connecting member 1, but the seal structure may be configured as a part integral with the connecting member. That is, the seal structure may be a part of the connecting member. In that case, the seal structure may be formed, for example, as a metal partition wall that is arranged substantially orthogonally to the axial direction and partitions the internal space of the connecting member 1 in the axial direction as in Modification Example 3 described later.

[0039] [Multi-piece grommet] As shown in FIG. 2, the multi-piece grommet 4 is formed in a plate shape from a material having elasticity and electrical insulation, and is arranged in the recess 3a of the holder 3 so as to cover the outer periphery of the connecting member 1, thereby sealing the outer periphery of the connecting member 1. More specifically, the multi-piece grommet 4 continuously covers the outer periphery of a part of the connecting member 1 in the axial direction including the separation part 13. However, in the present invention, the part of the connecting member 1 covered by the outer peripheral seal member is not particularly limited. The outer peripheral seal member according to the present invention may be any member that continuously covers at least a part of the outer periphery of the connecting member in the axial direction, but is not limited thereto.

[0040] The multi-piece grommet 4 is formed with through holes 4a extending along the axial direction of the connecting member 1. The connecting member 1 is inserted through the through holes 4a. In this embodiment, three through holes 4a are formed corresponding to the number of connecting members 1. Thus, the multi-piece grommet 4 has a structure in which a plurality (three in this example) of grommets are integrated. The material of the multi-piece grommet 4 is not particularly limited, and examples include rubbers such as ACM (acrylic rubber) and resin materials.

[0041] Protrusions 41 are formed on the outer peripheral portion of the multi-piece grommet 4, and protrusions 42 are formed on the inner wall of the through hole 4a. The protrusions 41 and 42 are formed as annular protrusions continuous in the circumferential direction and are elastically deformable. The multi-piece grommet 4 is fitted into the recess 3a of the holder 3 in a state where the protrusion 41 is crushed and compressed. The outer peripheral surface of the multi-piece grommet 4 and the inner peripheral surface of the recess 3a are in contact without a gap due to the restoring force of the protrusion 41, thereby sealing between the multi-piece grommet 4 and the holder 3. Further, the connecting member 1 is inserted through the through hole 4a so as to crush and compress the protrusion 42. The outer peripheral surface of the connecting member 1 and the inner wall surface of the through hole 4a are in contact without a gap due to the restoring force of the protrusion 42, thereby sealing between the connecting member 1 and the multi-piece grommet 4. As described above, between the connecting member 1 and the holder 3 is sealed by the multi-piece grommet 4. As a result, the outer periphery of the connecting member 1 is sealed. Thereby, it is possible to prevent the fluid from passing through and leaking out of the outer periphery of the connecting member 1.

[0042] In this embodiment, a multi-piece grommet 4 in which a plurality of grommets are integrated is adopted as the outer peripheral sealing member, but the outer peripheral sealing member according to the present invention is not limited thereto. The outer peripheral sealing member may be a single grommet or a single O-ring that seals the outer periphery for each connecting member. Further, as long as the electrical insulation between the plurality of connecting members is ensured, the outer peripheral sealing member according to the present invention does not necessarily have to have electrical insulation and may have conductivity. Also, the outer peripheral sealing member may be a resin molded body integrally molded with the connecting member or the holder by resin insert molding.

[0043] [Function and Effect] As described above, the connection structure 100 according to the present embodiment is attached to the motor 200 to which the fluid pressure acts, and electrically connects the lead wire 10 provided inside the motor 200 and the lead wire 20 provided outside the motor 200. The connection structure 100 has conductivity and includes at least one sleeve-shaped connection member 1 at both axial ends and a seal structure 2 disposed within the connection member 1. The connection member 1 has a first connection portion 11 formed at one end side and capable of connecting the lead wire 10, a second connection portion 12 formed at the other end side and capable of connecting the lead wire 20, and a separation portion 13 formed between the first connection portion 11 and the second connection portion 12 and separating the lead wire 10 and the lead wire 20 inside the connection member 1. The seal structure 2 seals the inside of the connection member 1 by being disposed in the separation portion 13.

[0044] 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. Further, by disposing the seal structure 2 in the separation portion 13 and sealing the inside of the connection member 1, it is possible to prevent the fluid from passing through the inside of the connection member 1 and leaking. Here, in the present embodiment, since the conductive wire 101 of the lead wire 10 and the conductive wire 201 of the lead wire 20 are formed as stranded wires, there is a possibility that oil may penetrate into the lead wires 10 and 20 due to capillary action. However, since the lead wires 10 and 20 are isolated from each other inside the connection member 1 by the seal structure 2, leakage of oil through the inside of the lead wires 10 and 20 is also prevented. As described above, according to the present embodiment, it is possible to suppress the oil in the internal space IS of the motor 200 from leaking to the external space ES of the motor 200 through the inside of the connection member 1. As a result, according to the present embodiment, the sealing performance of the connection structure 100 can be improved.

[0045] In addition, since the connection structure 100 according to the present embodiment adopts a simple structure in which a sealing member is disposed inside the connection member 1, it is relatively inexpensive and can surely seal even when applied to a device such as the motor 200 that generates vibration during operation. As a result, according to the connection structure 100 according to the present embodiment, it is possible to surely improve the sealing performance with a relatively inexpensive structure.

[0046] In the present embodiment, the holder 3 attached to the case 200a of the motor 200 is formed with the mounting hole 3b, but the present invention is not limited thereto. The holder 3 is not an essential configuration in the present invention, and the mounting hole according to the present invention may be formed in the housing of the device, for example.

[0047] In addition, in the present embodiment, at least one of the first connection portion 11 and the second connection portion 12 is formed at the axial end portion of the connection member 1 as a crimping portion connected to the conductive member by crimping. According to this, by forming at least one of the first connection portion 11 and the second connection portion 12 as a crimping portion having a relatively simple structure, the conductive members can be electrically connected with a relatively inexpensive structure. However, in the present invention, the connection form of the first connection portion and the second connection portion is not limited to crimping.

[0048] In addition, the sealing structure 2 according to the present embodiment is formed by an elastic body fitted into the separation portion 13. According to this, the inside of the connection member 1 can be surely sealed.

[0049] In addition, the connection structure 100 according to the present embodiment further includes a multi-piece grommet 4 disposed on the outer periphery of the connection member 1. The multi-piece grommet 4 is at least a part in the axial direction of the connection member 1 By continuously covering the outer periphery in the circumferential direction, the outer periphery of the connecting member 1 is sealed. According to this, by sealing the outer periphery of the connecting member 1 with the multi-ring grommet 4, it is possible to prevent fluid from passing through and leaking out through the outer periphery of the connecting member 1. That is, it is possible to suppress the oil in the internal space IS of the motor 200 from passing through the outer periphery of the connecting member 1 and leaking into the external space ES of the motor 200. Thus, the connection structure 100 according to the present embodiment can seal the inside of the connecting member 1 by the sealing structure 2 and seal the outer periphery of the connecting member 1 by the multi-ring grommet 4. As a result, while electrically connecting the inside and outside of the motor 200, it is possible to suppress the oil in the internal space IS of the motor 200 from leaking into the external space ES of the motor 200. Note that in the present invention, the outer peripheral sealing member is not an essential configuration.

[0050] [Modification Example] Hereinafter, a modification example of the connecting member according to the present embodiment will be described. In the description of the following modification example, the description will focus on the differences from the connecting member 1 described with reference to FIGS. 1 to 5, and the same components as those of the connecting member 1 will be denoted by the same reference numerals, and detailed description thereof will be omitted. [Modification Example 1]

[0051] FIG. 6 is a side view showing the state of the connection member 1A according to Modification Example 1 of the embodiment before the crimping process. In FIG. 6, a state in which the connection member 1A before being plastically deformed by the crimping process is viewed along a direction orthogonal to the first crimping direction and the axial direction is illustrated. In Modification Example 1, the first crimping direction and the second crimping direction coincide. Further, FIG. 7 is a top view showing the state of the connection member 1A according to Modification Example 1 of the embodiment before the crimping process. In FIG. 7, a state in which the connection member 1A before being plastically deformed by the crimping process is viewed along the first crimping direction (second crimping direction) is illustrated. In FIGS. 6 and 7, a state in which the seal structure 2 is disposed in the separation portion 13 is illustrated. As shown in FIGS. 6 and 7, between the first connection portion 11 and the separation portion 13 and between the second connection portion 12 and the separation portion 13 in the connection member 1A, slits 14, which are cutouts penetrating the connection member 1A, are formed. That is, the slits 14 are formed in the connection member 1A between the crimping portion and the seal structure 2. As shown in FIG. 7, the slit 14 is formed linearly and extends along a direction substantially orthogonal to the crimping direction and the axial direction. In the view in the crimping direction, the slit 14 extends so as to straddle the central axis A1 of the connection member 1A and is formed axially symmetric with respect to the central axis A1. The connection member 1A is partitioned into the first connection portion 11, the separation portion 13, and the second connection portion 12 by the slit 14. Hereinafter, the slit 14 formed between the first connection portion 11 and the separation portion 13 may be denoted by reference numeral 141, and the slit 14 between the second connection portion 12 and the separation portion 13 may be denoted by reference numeral 142 for description.

[0052] Note that 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 in which the major axis direction is substantially orthogonal to the axial direction of the connecting member 1A, or may be a polygonal shape in which the longitudinal direction is substantially orthogonal to the axial direction of the connecting member 1A. Examples of the polygonal shape include a triangular shape, a rectangular shape, and a rhombic shape. Further, the inclination angle of the slit with respect to the axial direction is not limited to approximately 90°. The slit may be inclined with respect to the axial direction and the radial direction. However, in the connecting member according to the present invention, the slit is not essential. Further, when forming a slit in the connecting member in the present invention, it may be formed between at least one of the crimping portions of the first connecting portion and the second connecting portion and the seal structure, and it is not necessary to be formed in both.

[0053] Here, the region adjacent to the slit 14 in the axial direction in the crimping portion is referred to as the "slit adjacent region" and is represented by a dot pattern in FIGS. 6 and 7. Hereinafter, the slit adjacent region of the first connecting portion 11 may be denoted by reference numeral 11a, and the slit adjacent region of the second connecting portion 12 may be denoted by reference numeral 12a for description. The slit adjacent regions 11a and 12a are more likely to be deformed than other parts of the connecting member 1A by being adjacent to the slit 14. Therefore, in the crimping process of the connecting member 1A, when the first connecting portion 11 and the second connecting portion 12 are pressed in the crimping direction, the slit adjacent regions 11a and 12a are plastically deformed preferentially over the separation portion 13. Thereby, the plastic deformation of the separation portion 13 can be further suppressed.

[0054] By plastically deforming the slit adjacent regions 11a and 12a by being pressed and crushed in the crimping direction by the crimping process, the conductive wire 101 of the lead wire 10 is crimped to the first connecting portion 11, and the conductive wire 201 of the lead wire 20 is crimped to the second connecting portion 12.

[0055] As described above, according to Modification 1, by forming the slit 14 between the crimping portion of the connecting member 1A and the seal structure 2, plastic deformation of the separation portion 13 can be suppressed in the crimping process of the connecting member 1A. As a result, the sealing performance of the outer periphery of the separation portion 13 can be improved.

[0056] Here, as shown in FIG. 6, let the axial distance between the tip of the crimping portion and the seal structure 2 be L2. Specifically, L2 is the axial distance from the axially foremost point (i.e., the point farthest from the seal structure 2) in the crimping portion where the slit 14 is formed between the crimping portion and the seal structure 2 to the point on the seal structure 2 closest to the crimping portion. Also, let the height of the crimping portion before crimping (before plastic deformation) in the crimping direction be H2. Further, let the depth of the slit 14 in the crimping direction be S1. The depth S1 is the distance from the opening to the end of the slit 14 when viewed along a direction orthogonal to the crimping direction and the axial direction of the connecting member 1A.

[0057] At this time, it is preferable that L2 ≧ H2 × 0.68 and 0.25 ≦ S1 / H2 ≦ 0.67. By setting 0.25 ≦ S1 / H2 and L2 ≧ H2 × 0.68, the influence of the plastic deformation of the crimping portion on the separation portion 13 can be reduced, and the plastic deformation of the separation portion 13 can be suppressed. As a result, the deformation amount DX of the separation portion 13 can be suppressed to 0.085 [mm] or less. Consequently, the sealing performance of the outer periphery in the separation portion 13 can be further improved. Also, by setting S1 / H2 ≦ 0.67, the cross-sectional area of the connecting member 1A at the portion where the slit 14 is formed can be ensured, and the electrical conductivity of the connecting member 1A can be ensured. Furthermore, from the viewpoint of space saving, it is preferable that L2 ≦ H2 × 6, and more preferably L2 ≦ H2 × 4. By doing so, the enlargement of the connecting member 1A can be suppressed, and space saving can be achieved.

[0058] [Modification Example 2] FIG. 8 is a perspective view showing a state before the crimping process of the connecting member 1B according to Modification 2 of the embodiment. As shown in FIG. 8, the connecting member 1B according to Modification 2 is different from the above-described connecting member 1A in that the slit 141 formed on the first connection portion 11 side and the slit 142 formed on the second connection portion 12 side are formed at different positions in the circumferential direction. In other words, the slit 141 and the slit 142 are arranged so as to be displaced around the central axis A1 of the connecting member 1B. That is, the slit adjacent region 11a of the first connection portion 11 and the slit adjacent region 12a of the second connection portion 12 are arranged so as to be inclined with respect to each other around the central axis A1. Therefore, the first crimping direction of the first connection portion 11 and the second crimping direction of the second connection portion 12 are different. According to this, by making the first crimping direction of the first connection portion 11 and the second crimping direction of the second connection portion 12 different, it is possible to make the direction in which the first connection portion 11 is crushed and the direction in which the second connection portion 12 is crushed different in the crimping process. Thereby, the influence on the separation portion 13 due to the plastic deformation of the first connection portion 11 and the second connection portion 12 in the crimping process can be reduced. As a result, the plastic deformation of the separation portion 13 can be suppressed.

[0059] Here, the deviation angle around the central axis A1 between the slit 141 and the slit 142, that is, the angle of the inferior angle formed by the first crimping direction and the second crimping direction is defined as θ1. At this time, from the viewpoint of suppressing the plastic deformation of the separation portion 13, it is preferably 30[°]≦θ1≦180[°], but it is not limited to this.

[0060] [Modification 3] FIG. 9 is a cross-sectional view of the connection structure 100C according to Modification 3 of the embodiment. As shown in FIG. 9, the connection structure 100C according to Modification 3 is different from the above-described connection structure 100 in that the seal structure 2C is formed by a part of the connection member 1C. The seal structure 2C according to Modification 3 is formed integrally with the connection member 1C as a metal partition wall that closes the separation portion 13. The seal structure 2C is arranged substantially orthogonally to the axial direction, and the internal space of the connection member 1C is partitioned in the axial direction by the seal structure 2C. According to Modification 3, the inside of the connection member 1C can be reliably sealed.

[0061] [Modification Example 4] FIG. 10 is a cross-sectional view of a connection structure 100D according to Modification Example 4 of the embodiment. As shown in FIG. 10, the connection structure 100D according to Modification Example 4 is different from the above-described connection structure 100 in that it is formed of a resin molded body in which a seal structure 2D is filled in a separation portion 13. The seal structure 2D according to Modification Example 4 is integrally formed with the connection member 1 by, for example, resin insert molding. The resin molded body forming the seal structure 2D 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. 10, the seal structure 2D may be filled up to the inside of the first connection portion 11 and the second connection portion 12 to fix the conductive wires 101 and 201 of the lead wires 10 and 20. According to Modification Example 4, the inside of the connection member 1 can be reliably sealed.

[0062] [Simulation and Test] The amount of deformation of the connection member when a crimping process is performed on the connection member according to the present embodiment was simulated by CAE analysis. Also, a leakage test was performed on the connection structure. Note that the present invention is not limited to the embodiments described below.

[0063] As Examples 1 to 8, 13, 14, 16, 17, 19, 20 and Comparative Example 1, an analysis model having a slit corresponding to the connection member 1A according to Modification Example 1 was created. As Examples 9 to 12, 15, 18, 21, 22 and Comparative Examples 2 and 3, an analysis model having no slit corresponding to the connection member 1 was created. Table 1 shows the conditions, simulation results, and leakage test results of Examples 1 to 22 and Comparative Examples 1 to 3. Note that h1 is the seal length and represents a value half of the axial length of the seal structure (see FIGS. 3 and 6).

Table 1

[0064] In the simulation, a pressure assumed for crimping the lead wire to the analysis model was applied from the crimping direction, and the amount of deformation DX at each part of the analysis model was analyzed. The material of the analysis model was copper. The pressure applied to the crimping part was set to the pressure assumed when crimping with an appropriate crimping tool conforming to the dimensions of the connection member.

[0065] FIG. 11 is a diagram showing the simulation results of Example 1. FIG. 11(A) is a perspective view of the analysis model. FIG. 11(B) is a cross-sectional view orthogonal to the axial direction in the separated part 13 of the analysis model. The gradation scale shown in FIGS. 11(A) and (B) represents the amount of deformation.

[0066] As shown in Table 1, when there is no slit (Examples 9 to 12, 15, 18, 21, 22), it was found that the amount of deformation DX becomes 0.085 or less by setting L1≧H1×0.88 as in Examples 9 to 12 and 15. Further, when there is a slit (Examples 1 to 8, 13, 14, 16, 17, 19, 20), it was found that the amount of deformation DX becomes 0.085 or less by setting 0.25≦S1 / H2 and L2≧H2×0.68 as in Examples 1 to 8, 13, 14, 16, and 17.

[0067] In the leakage test, for Examples 1, 2, 3, 19, 20, 21 and Comparative Examples 1 to 3, the connection structures shown in FIGS. 1 and 2 were actually fabricated, and a fluid leakage test was conducted under predetermined conditions. In Comparative Examples 1 to 3, no seal structure was arranged inside the connection member. In the leakage test, the presence or absence of fluid leakage was confirmed for each of the inside and the outer periphery of the connection member. When no fluid outflow occurred, the determination was "〇", when a relatively small amount of fluid leakage was recognized, the determination was "△", and when a relatively large amount of fluid leakage was recognized, the determination was "×". As shown in Table 1, for Examples 1, 2, 3, 19, 20, 21 having a seal structure, no liquid leakage from the inside occurred. For Comparative Examples 1 to 3 having no seal structure, fluid leakage from the inside occurred. For Examples 1, 2, 3 and Comparative Example 1, no fluid leakage occurred from the outer peripheral side, and for Examples 19, 20, 21 and Comparative Example 2, a very small amount of leakage from the outer peripheral side was recognized. For Comparative Example 3, leakage from the outer peripheral side was recognized. Thus, it was found that by suppressing the amount of deformation DX to 0.085 [mm] or less, the seal performance on the outer peripheral side can be further improved.

[0068] <Others> As described above, the embodiments of the connection structure according to the present invention have been described. However, each aspect disclosed in this specification can be combined with any other features disclosed in this specification.

Explanation of Reference Numerals

[0069] 1 ······ Connection member 2 ······ Seal structure 3 ······ Holder 4 ······ Multi-piece grommet (an example of an outer peripheral seal member) 5 ······ Gasket 6 ······ Bolt 10, 20 ··· Lead wires (an example of a first conductive member and a second conductive member) 11 ······ First connection portion 12 ······ Second connection portion 13 ······ Spacing portion 100 ······ Connection structure

Claims

1. A connection structure for electrically connecting conductive members, comprising: a connection member having conductivity and at least one of both axial ends being sleeve-shaped; and a seal structure disposed inside the connection member, wherein the connection member has a first connection portion formed at one end side and connectable to the first conductive member, a second connection portion formed at the other end side and connectable to the 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 inside the connection member; the seal structure seals the inside of the connection member by being disposed in the separation portion; a connection structure.

2. At least one of the first connection portion and the second connection portion is formed at an axial end of the connection member as a crimping portion connected to the conductive member by crimping. The connection structure according to Claim 1.

3. When the axial distance between the tip of the crimping portion and the seal structure is L1, and the height of the crimping portion before crimping in the crimping direction is H1, L1 ≥ H1 × 0.

88. The connection structure according to Claim 2.

4. A slit is formed in the connection member between the crimping portion and the seal structure. The connection structure according to Claim 2.

5. When the axial distance between the tip of the crimping portion and the seal structure is L2, the height of the crimping portion before crimping in the crimping direction is H2, and the depth of the slit in the crimping direction is S1, L2 ≥ H2 × 0.68 and 0.25 ≤ S1 / H2 ≤ 0.

67. The connection structure according to Claim 4.

6. The seal structure is formed by an elastic body fitted into the separation portion. The connection structure according to Claim 1 or 2.

7. The seal structure is integrally formed with the connection member as a partition wall closing the separation portion. The connection structure according to Claim 1 or 2.

8. The seal structure is formed by a resin molded body filled in the separation portion. The connection structure according to Claim 1 or 2.

9. The connection structure further includes an outer peripheral seal member disposed on the outer periphery of the connection member, wherein the outer peripheral 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 circumferential direction. The connection structure according to Claim 1 or 2.

10. ​ ​ ​ The connection member is arranged to receive the pressure action of the fluid at at least one end side in the axial direction. The connection structure according to claim 1 or 2.

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