JP4720168B2 - Shielded wire - Google Patents

Description

  The present invention relates to a shielded electric wire for power supply of equipment, and more particularly to a shielded electric wire used for power supply to various equipment of an automobile.

  The shielded electric wire has a braided shield composed of braids such as a copper wire and a tin-plated copper wire having a wire diameter of several tens to several hundreds of μm on the outside of the covered electric wire. By connecting a metal connector to both ends of the braided shield and grounding the connector, a shielding effect for preventing malfunction due to electromagnetic waves or the like can be obtained.

  In recent years, in automobiles, the spread of hybrid cars and the electrification of equipment are progressing. For this reason, in shielded wires used in various devices of automobiles, higher voltages and higher currents have been achieved. In addition, as the number of wiring materials (shielded wires) tends to increase with the spread of hybrid vehicles and the electrification of equipment, the space for installing wiring materials can be saved (bending of wiring materials is easy). Is required).

  As shown in FIG. 34, connection terminals 356 and 356 are crimped to both ends of the shielded electric wire 350, and a crimp mark 356a is formed in the crimped portion. As shown in FIG. 35, a shielded wire 350 has an insulator 355, a braided shield 352, a coating layer (insulator) 351 in order from the inner periphery to the outer periphery of the conductor 357. Have As shown in FIG. 36, the shielded wire 350 has a cross-sectional view taken along line 36-36. A ring 353 is provided. A shield connector 354 is provided at the folded base of the braided shield 352 (the boundary between the braided wire 352 and the insulator 355). The shield connector 354 has a screw terminal (not shown) for grounding, and is grounded via this terminal.

  One end side of the shielded electric wire 350 having such a structure is connected to the casing of the inverter, and the other end side is connected to the casing of the transmission or the like (see, for example, Patent Document 1).

JP 2002-208456 A

  Since the conventional shielded wire 350 uses a heat-resistant resin as the insulator 355 and is entirely covered with the braided shield 352, the bendability is not good. For this reason, when the shielded electric wire 350 is attached to the vehicle body or the like, it is difficult to bend the shielded electric wire 350 along the shape of the attachment location, and there is a difficulty in handling at the time of attachment.

  In addition, when the shielded electric wire 350 is attached to the inverter housing, it is necessary to individually connect the connection terminal 356 portion through which current flows and the shield connector 354 portion. Since the shield connector 354 needs to be grounded, the screw terminal and the housing are electrically connected, but there is a problem that the efficiency of this connection work is not good.

Furthermore, depending on the location where the shielded electric wire 350 is attached, muddy water, gravel or the like may fly, and the gravel or the like hits the shielded electric wire 350, so that the covering material 351 may be broken.

  In addition, when the shielded electric wire 350 is attached to a location close to the engine of an automobile, it is exposed to vibration and high temperature. Therefore, if the heat resistance limit is exceeded, the coating material 351 may crack and the braided shield 352 may be corroded or broken. As a result, there is a problem that the shielding effect is lowered. For this reason, it is necessary to make the coating | covering material 351 into the strong structure and material which can endure a vibration and high temperature. In particular, it is necessary to flow a large current through a shielded electric wire used for connection with a power supply housing on the transmission side, and naturally a current also flows through a braided shield 352 used as a shield. As a result, the braided shield 352 generates heat, and there is a possibility that the resistance value at the connection portion between the power supply housing and the shielded electric wire becomes high. Further, as a result of the braided shield 352 being heated, the covering material 351 may be exposed to a high temperature, and the covering material 351 may be cracked.

  An object of the present invention, which was created in view of the above circumstances, is to provide a shielded electric wire having good bendability, impact resistance, and heat resistance.

In order to achieve the above object, a shielded electric wire according to the present invention is a shielded electric wire comprising an electric wire body in which a conductor made of a single wire or a stranded wire is covered with an insulator, and a shield member provided on the outer periphery of the electric wire body In
The shield member is composed of a cylindrical body provided with a braided shield and an outer sleeve sequentially around the inner sleeve, and a metal pipe provided in abutment with the outer sleeve of the cylindrical body, and one end side of the cylindrical body is , while electrically connected by melting joining the outer sleeve and the metal pipe, the other end is obtained by the connector member and electrically connected with the flange portion.

  The braided shield is preferably made of copper or a copper alloy, and the metal pipe and the connector member are preferably made of aluminum or an aluminum alloy. The braided shield, the metal pipe, and the connector member are preferably made of aluminum or an aluminum alloy.

  According to the present invention, an excellent effect is obtained that a shielded electric wire having excellent impact resistance, heat resistance, and connectivity with a housing is obtained.

  A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 shows a plan view of a shielded electric wire according to a preferred embodiment of the present invention.

  As shown in FIG. 1, the shielded electric wire according to the present embodiment is provided with a shield member around an electric wire body 20 formed by covering a conductor 17 made of a single wire or a stranded wire with an insulator 15. The connection terminals 16 and 16 are connected to both ends of the shielded electric wire. The connection terminal 16 on one side (left side in FIG. 1) is connected to, for example, an inverter side described later, and the connection terminal 16 on the other side (right side in FIG. 1) is connected to, for example, a transmission side described later.

  The shield member includes a cylindrical body 50 shown in FIG. 6 and a metal pipe 11 shown in FIG. The cylindrical member 50 and the metal pipe 11 are provided to face each other, and the cylindrical member 50 and the metal pipe 11 are electrically connected via the welded portion 140, whereby the shield member is formed. As shown in FIGS. 5 and 6, the cylindrical body 50 is formed by sequentially providing a braided shield 12 and an outer sleeve 22 around the inner sleeve 21. The braided shield 12 is a long member provided over the entire length of the cylindrical body 50. The inner sleeve 21 and the outer sleeve 22 are short members that cover the vicinity of the transmission side end portion of the cylindrical body 50.

  The shield layer in the shield member is different in the longitudinal direction of the shielded electric wire, and specifically, it is different at the outer sleeve 22 portion of the cylindrical body 50 as a boundary. That is, the shield layer on the inverter side is a braided shield 12 as shown in FIG. 2, and the shield layer on the transmission side is a metal pipe 11 as shown in FIG. For this reason, the cross-sectional shape of the outer sleeve 22 is varied in the longitudinal direction.

  As shown in FIG. 2, the outer sleeve 22 on the inverter side is a molded portion 22 a having a polygonal cross section (hexagonal shape in FIG. 2). As shown in FIG. 3, the outer sleeve 22 on the transmission side is a non-molded portion 22b having a circular cross section.

  The shield member is provided so as to surround the electric wire main body 20, and has a space portion 23 for enclosing the electric wire main body therein (see FIGS. 2 to 4). That is, a gap is provided between the electric wire body 20 and the shield member. As a result, the bendability of the shielded electric wire is improved, and no stress is applied to the electric wire body 20 when the shielded electric wire is bent.

  A crimp ring 51 is provided in the vicinity of the end of the braided shield 12 on the inverter side in the cylindrical body 50. As shown in FIG. 5, the pressure-bonding ring 51 is a forming portion 51 a having a polygonal cross section (hexagonal shape in FIG. 5). The braided shield 12 between the crimp ring 51 and the outer sleeve 22 is covered with an insulating coating 18.

  A shield connector (connector member) 500 is provided at the end of the braided shield 12 on the inverter side (non-metallic pipe side of the cylinder 50). As shown in FIG. 23, the shield connector 500 has a cylindrical body connection portion 501 on the inverter side and a device connection portion 503 on the transmission side with the flange portion 502 interposed therebetween, and the flange portion 502 and the device connection portion 503 are interposed therebetween. Connected to ground.

  The outer sleeve 22, the metal pipe 11, and the connector member 500 are preferably made of the same material (or materials having substantially the same chemical composition). Specifically, examples of the constituent material of the outer sleeve 22, the metal pipe 11, and the connector member 500 include aluminum or an aluminum alloy, preferably an Al—Si—Mg alloy having good corrosion resistance and brazing properties. As the outer sleeve 22 and the metal pipe 11, for example, a tube material made of A6063 and having an inner diameter of 10 mm and a wall thickness of 1 mm is used. The connector member 500 is made of, for example, A6063 and has the same diameter and the same thickness as the inner sleeve 21.

  Here, by configuring the metal pipe 11 with aluminum or an aluminum alloy, the metal pipe 11 can protect the electric wire body 20 from high heat even if a shielded electric wire is laid near a device that is lightweight and generates high temperature. This is because the heat generated in the braided shield 12 can be efficiently radiated. The reason why the outer sleeve 22, the metal pipe 11, and the connector member 500 are made of the same material (or a material having substantially the same chemical composition) is to join the same kind of metal. This is because in the case where the joining is between different metals, if moisture adheres to the joining portion, a potential difference is generated and corrosion may occur.

  Examples of the constituent material of the inner sleeve 21 include stainless steel, preferably austenitic stainless steel. As the inner sleeve 21, for example, a tube material made of SUS304 (JIS standard) and having an outer diameter of 9 mm and a wall thickness of 0.2 mm is used.

  Examples of the constituent material of the braided shield 12 include copper, a copper alloy, aluminum, and an aluminum alloy, and preferably include copper or a copper alloy. Any copper or copper alloy that is conventionally used as a braided shield can be used. Examples of the aluminum or aluminum alloy include Al-Fe-Zr alloys having good heat resistance, flex resistance, and elongation, and high strength. For example, the wire diameter of the Al-Fe-Zr alloy is 0.2. A braided wire of mm is used. The length of the braided shield 12 varies depending on the use of the shielded wire and the installation location, but is, for example, 200 mm in length.

  The conductor 17 may be either a single wire material or a stranded wire material obtained by twisting a plurality of single wire materials, and all conductors conventionally used as shielded wires are applicable. For example, 19 tin-plated copper wires having an outer diameter of 0.32 mm are twisted to form a core wire, and 19 more core wires are twisted to form a stranded wire material (conductor 17). In addition, as the insulator 15 covering the conductor 17, all insulators conventionally used as shielded wires can be applied, and examples thereof include Frontrex (registered trademark).

  As the connection terminal 16, all connection terminals conventionally used as shielded wires can be applied, for example, 38-S6 (the inner diameter of the wire gripping portion is 9.4 mm, the outer diameter is 13.3 mm, and the length is 14 mm). Can be mentioned.

  Next, the manufacturing method of the shielded wire according to the present embodiment will be described.

  First, the cylindrical body 50 shown in FIGS. 6 and 7 is prepared. As shown in FIG. 8, the cylindrical body 50 is arranged in a space 74 formed by the die surfaces 73 a and 73 b of the compression dies 71 and 72. To do. At this time, the outer sleeve 22 on the inverter side is disposed in the space 74.

  After that, as shown in FIG. 9, the compression dies 71 and 72 are moved in directions close to each other, whereby the outer sleeve 22 is compressed from the outside. Thereafter, dies 81 and 82 are also inserted into the internal space 80 of the cylindrical body 50 in the compression-molded portion, and the outer sleeve 22 is compression-molded from the outside and the inside. As a result, as shown in FIGS. 10 and 11, the inner sleeve 21, the braided shield 12, and the outer sleeve 22 are mechanically joined to the portion of the outer sleeve 22 sandwiched between the dies 71, 72 and 81, 82. The formed portion 22a is formed, and the remaining outer sleeve 22 becomes the unformed portion 22b.

  Here, the forming portion 22a is formed in order to secure a contact area between the braided shield 12 and the outer sleeve 22 and increase electrical contact, and the braided shield 12 and the outer sleeve 22 are integrally joined. This is to ensure the mechanical strength of the braided shield 12 in the molding portion 22a.

  On the other hand, as shown in FIG. 12, an electric wire body 20 in which the conductor 17 is covered with an insulator 15 is prepared, and one end side (right side in FIG. 12) of the electric wire body 20 is inserted into the metal pipe 11. In a state where the electric wire body 20 is inserted into the metal pipe 11, a predetermined bending process is performed on the metal pipe 11 prior to fusion bonding described later. This bending process may be performed after the melt bonding.

  Next, as shown in FIG. 13, the other end side (the left side in FIG. 13) of the electric wire body 20 is inserted into the cylindrical body 50 shown in FIG. 10. As a result, the unformed portion 22b of the outer sleeve 22 in the cylindrical body 50 and the metal pipe 11 are brought into contact with each other.

  Next, as shown in FIG. 14, the braided shield 12 (hereinafter referred to as the exposed shield 130) exposed from the unmolded portion 22 b of the cylindrical body 50 is spread outward in the radial direction, and a metal is interposed between the braided shield 12 and the inner sleeve 21. The pipe 11 is inserted and brought close to the extent that the unformed portion 22b of the outer sleeve 22 and the metal pipe 11 are almost in contact with each other. As a result, the exposure shield 130 is covered on the cylindrical body side end portion (left end portion in FIG. 14) of the metal pipe 11.

Next, as shown in FIG. 15, the laser beam L is oscillated from the laser welder head 142 of the laser welder (for example, YAG laser welder) 141, and the outer sleeve 22 is not formed using the laser beam L. The adjacent portion between the portion 22b and the metal pipe 11 is fusion bonded. That is, in this proximity portion, the end surface of the outer sleeve 22 and the end surface of the metal pipe 11 are welded with the braided shield 12 interposed. This fusion bonding is continuously performed over the entire circumference of the proximity portion. As a result, the metal pipe 11, the outer sleeve 22, and the braided shield 12 are reliably welded at the melt-bonded portion 140 and are joined metallically. As a result, corrosion and heat generation at the melt bonded portion 140 are suppressed. Further, by performing fusion bonding of the proximity portion with the exposure shield 130 placed on the cylindrical body side end portion of the metal pipe 11, the electrical connection of the metal pipe 11, the outer sleeve 22, and the braided shield 12 becomes more reliable. .

  Next, the braided shield 12 exposed from the exposed shield 130 and the molded portion 22a of the cylindrical body 50 (hereinafter referred to as the exposed shield 145) is insulated. For example, heat-shrinkable tubes each having a length that completely covers the exposure shields 130 and 145 are prepared, and the heat-shrinkable tubes are shrunk by hot blow after being placed on the exposure shields 130 and 145 so as to adhere to the shield member. The insulating coating 18 is formed.

Next, as shown in FIG. 22, a part of the insulation coating 18 on the transmission side (left side in FIG. 22) is peeled off to expose the braided shield 12 (hereinafter referred to as an exposed shield 225). The connection terminals 16 and 16 are connected to both ends of the conductor in the electric wire body 20. Further, the crimp ring 51 is fitted from the transmission side of the electric wire body 20 and is positioned closer to the transmission side than the exposed shield 225.

  Next, as shown in FIG. 23, the exposure shield 225 is folded back (turned up) toward the insulating coating 18 side. Further, the connector member 500 is fitted from the transmission side of the electric wire body 20, and the cylindrical body connecting portion 501 is brought into contact with (or substantially in close proximity to) the folded base portion 225a of the exposure shield 225. Thereafter, as shown in FIG. 24, the folded exposure shield 225 is returned to the original position, and the exposure shield 225 is put on the cylindrical body connecting portion 501.

  Next, as shown in FIG. 25, the crimp ring 51 fitted in advance is moved and positioned at the exposed shield 225 portion. At this time, the front end portion 225 b of the exposure shield 225 is slightly exposed from the crimping ring 51. Thereafter, the pressure-bonding ring 51 is compression-molded and formed into a forming portion 51a having a polygonal cross section (hexagonal shape in FIG. 5) as shown in FIG.

  Here, the compression ring 51 is subjected to compression molding in order to secure a contact area between the exposure shield 225 and the cylindrical body connection portion 501 and increase electrical contact. Also, the exposure shield 225 and the cylindrical body connection portion. This is because the mechanical strength of the exposed shield 225 at the portion of the pressure-bonding ring 51 is secured by integrally bonding the members 501.

  Next, as shown in FIG. 27, a laser beam L is oscillated from a laser welder head 272 of a laser welder (for example, a YAG laser welder) 271, and the cylindrical body connection portion 501 is connected with this laser beam L. The formed crimp ring 51 is melt-bonded. This fusion bonding is continuously performed over the entire circumference of the cylindrical body connecting portion 501. As a result, the cylindrical body connecting portion 501, the crimping ring 51, and the exposure shield 225 are reliably welded and joined metallically at the melt joint portion 270. As a result, corrosion and heat generation at the melt bonded portion 270 are suppressed. Further, by performing fusion bonding of the tip end portion 225b with the exposure shield 225 placed on the cylindrical body connecting portion 501, the electrical connection of the cylindrical body connecting portion 501, the crimping ring 51, and the exposure shield 225 becomes more reliable. .

  Finally, the cylindrical body connecting portion 501, the crimp ring 51, and the exposure shield 225 are insulated. For example, heat-shrinkable tubes having lengths that completely cover these portions are prepared, and after covering these portions, hot blow is performed to shrink the heat-shrinkable tubes so that these portions are brought into close contact with each other. As shown in FIG. 2, an insulating coating 281 is formed. Thereby, shielded electric wire 280 according to the present embodiment is obtained.

  The connection terminal 16 on the side of the shielded wire 280 to which the connector member 500 is connected (the left side in FIG. 28) is connected to an inverter housing (for example, made of aluminum or aluminum alloy (not shown)), and the metal pipe 11 The connection terminal 16 on the side to which is connected (the right side in FIG. 28) is connected to a transmission housing (not shown). The device connection portion 503 of the connector member 500 is inserted into a connection hole formed in advance in the inverter housing until the flange portion 502 contacts the inverter housing. Thereafter, the peripheral edge portion of the flange portion 502 and the inverter housing are fixed and connected by fastening means such as bolts. At this time, it is preferable to form a groove for fitting a sealing member such as an O-ring on the side of the device connecting portion of the flange portion 502. Thereby, the airtightness in the connection part of the flange part 502 and an inverter housing | casing increases.

  The shielded electric wire 280 according to the present embodiment mechanically connects the connector member 500 provided at the end on the inverter side and the inverter housing, thereby connecting the ground wire between the shielded electric wire 280 and the inverter housing to the housing of the housing. Can be done on the outside. Therefore, according to the shielded electric wire 280 according to the present embodiment, the screw terminal and the inverter housing are connected via the ground wire or the like as in the connection of the conventional shielded electric wire 350 and the inverter housing shown in FIG. There is no need to connect. Therefore, the connection workability between the shielded electric wire 280 and the inverter housing is simple and good.

  The shielded electric wire 280 according to the present embodiment does not use the metal pipe 11 as the shield layer of the shield member over the entire length in the longitudinal direction, but is strong and heat resistant on the side that is vibrated and exposed to high temperatures (for example, the transmission side). The metal pipe 11 has good properties, and the other side (for example, the inverter side) is constituted by the braided shield 12. When the entire shield layer is composed of the metal pipe 11, the heat resistance of the shield member becomes good over the entire length of the shielded electric wire. However, since the shock caused by vibration concentrates on the connection portion of the shielded wire on the transmission side, it is not preferable. Therefore, in shielded electric wire 280 according to the present embodiment, in order to avoid impact concentration, flexible braided shield 12 is used, and a hybrid structure of braided shield 12 and metal pipe 11 is employed.

  In the shielded electric wire 280 according to the present embodiment, the inverter side of the outer sleeve 22 and the pressure-bonding ring 51 in the cylindrical body 50 constituting the shield member are compression-molded into molding portions 22a and 51a having a polygonal cross section. As a result, the outer sleeve 22 and the braided shield 12 and the crimping ring 51 and the exposed shield 225 (braided shield 12) are crimped, and a contact area between them, that is, electrical contact can be sufficiently ensured. Here, the outer sleeve 22, the metal pipe 11, and the braided shield 12 are melt-bonded. The connector member 500, the braided shield 12, and the pressure-bonding ring 51 are melt-bonded. For this reason, the current flowing through the braided shield 12 of the shield member flows in the order of the connector member 500 → the braided shield 12 → the braided shield 12 and the outer sleeve 22 → the metal pipe 11. Since a large current flows through the braided shield 12, Joule heat is generated. At this time, if the electrical contact between the crimping ring 51 and the exposure shield 225 and the outer sleeve 22 and the braided shield 12 is insufficient, the current becomes difficult to flow through the braided shield 12 and the outer sleeve 22, and the resistance value becomes high. End up. Accordingly, the temperatures of the melt-bonded portion 270 of the connector member 500, the braided shield 12, and the pressure-bonding ring 51, and the melt-bonded portion 140 of the braided shield 12, the outer sleeve 22, and the aluminum pipe 11 are increased. As this temperature rises, a vicious cycle occurs in which the resistance values of the melt-bonded portions 140 and 270 further increase. As a result, the melt-bonded portions 140 and 270 are melted, and there is a possibility that the connector member 500 and the cylinder 50 and the connection between the cylinder 50 and the metal pipe 11 are insufficient.

  In the shielded electric wire 280 according to the present embodiment, the transmission side of the outer sleeve 22 in the cylindrical body 50 constituting the shield member is not formed by compression, but is formed as an unformed portion 22b having a circular cross section. As a result, the metal pipe 11 having a circular cross section and the cylindrical body 50 can be easily and reliably joined.

  The shielded electric wire 280 according to the present embodiment can hold the shape of the braided shield 12 well when the inner sleeve 21 is made of stainless steel having excellent strength during compression molding of the molded portion 22a. Further, since the inner sleeve 21 is made of stainless steel having a low thermal conductivity, the thermal effect is not exerted on the electric wire body 20 inside the shield member when the cylindrical body 50 and the metal pipe 11 are melt-bonded.

  The shielded electric wire 280 according to the present embodiment is superior in shielding effect than the conventional material and has high reliability. In the conventional shielded electric wire 350 shown in FIG. 34, when the coating layer 351 of the shield member is broken due to high temperature, vibration, or the like, the braided shield 352 is corroded and disconnected, and the shielding effect may not be obtained. The shielded electric wire 280 according to the present embodiment has the effect that the aluminum pipe conducts heat and dissipates heat because the shield layer at a location exposed to high temperature and vibration is made of the metal pipe 11, for example, an aluminum pipe. Moreover, even when the coating layer is broken and the aluminum pipe is exposed, the shielding effect is maintained because the aluminum pipe has good strength and heat resistance. Moreover, since an oxide film is formed on the surface of aluminum, the aluminum pipe is excellent in corrosion resistance.

  As described above, the shielded electric wire according to the present embodiment is expected to be subjected to external impact such as vibration, and can be attached to a location where the temperature becomes high, and a heat generation phenomenon in the shield member can be avoided. Therefore, the shielded electric wire according to the present embodiment has heat resistance and corrosion resistance, such as a portion (engine, motor, transmission, etc.) near the engine that becomes high temperature, an electric braking device, an electric steering device, etc. It is suitable for devices that are strongly required.

  In the method for manufacturing a shielded wire according to the present embodiment, as shown in FIG. 14, after the exposure shield 130 is put on the cylindrical body side end portion of the metal pipe 11, the unformed portion 22 b of the outer sleeve 22 and the metal pipe 11 are covered. Although the case where the adjacent part of the material is melt-bonded has been described, the present invention is not particularly limited thereto.

  For example, as shown in FIG. 16, the metal pipe 11 prepared in advance is placed on the exposure shield 130, and the unformed portion 22 b of the outer sleeve 22 and the metal pipe 11 are brought into contact with each other. Thereafter, as shown in FIG. 17, the contact portion may be melt-bonded to form a melt-bonded portion 140. The inner diameter of the metal pipe 11 is formed slightly larger than the outer diameter of the braided shield 12.

  Also, as shown in FIG. 18, after the exposure shield 130 is folded back (turned up) to the unformed portion 22b side of the outer sleeve 22, the metal pipe 11 prepared in advance is put on the inner sleeve 21 and the outer sleeve 22 is covered. The unformed part 22 b of the sleeve 22 and the metal pipe 11 are brought into contact with each other through the exposure shield 130. Thereafter, as shown in FIG. 19, the contact portion may be melt-bonded to form a melt-bonded portion 140. The inner diameter of the metal pipe 11 is formed slightly larger than the outer diameter of the inner sleeve 21.

  Further, as shown in FIG. 20, after the exposure shield 130 is folded back to the unformed portion 22 b side of the outer sleeve 22, the metal pipe 11 prepared in advance is covered to the tip 191 of the folded portion of the exposure shield 130. Thereafter, as shown in FIG. 21, the melt-bonded portion 140 may be formed by performing melt-bonding at the tip 191 position of the folded portion. The inner diameter of the metal pipe 11 is slightly larger than the outer diameter of the folded portion of the exposure shield 130.

  In the shielded wire manufacturing method according to the present embodiment, the case where the unformed portion 22b of the outer sleeve 22 and the adjacent portion of the metal pipe 11 are melt-bonded by laser welding has been described. It is not limited to. For example, fusion methods other than laser welding, for example, welding methods such as electron beam welding, TIG welding, and MIG welding may be used. Since electron beam welding is performed in a vacuum chamber, the generation of oxides can be suppressed, and the number of heat-affected zones other than the portion to be melted can be reduced. For this reason, the strength reduction in the melt bonded portion 140 is reduced. TIG welding can prevent oxidation by the shielding gas, and the apparatus is simple, so the welding cost is low. In MIG welding, welding metal is supplied and welding is performed while preventing oxidation with a shielding gas, so that the thin wire constituting the braided shield 12 can be pressed in with molten metal, and the appearance is a beautiful fusion joint 140 can be obtained. Further, instead of welding, an ultrasonic bonding method that is solid phase bonding, a friction diffusion bonding (FSW) method, or the like may be used.

  Next, a modified example of the shielded electric wire according to the present embodiment will be described based on the attached drawings.

  In the cylindrical body 50 shown in FIG. 6 in the shielded electric wire according to the present embodiment, the inner sleeve 21, the braided shield 12, and the outer sleeve 22 are separate members.

  On the other hand, the cylindrical body of this modification is an integral member of the inner sleeve and the outer sleeve that constitute the cylindrical body. Specifically, as shown in FIG. 29, the inner sleeve 211, an outer sleeve having an inner diameter larger than the outer diameter of the inner sleeve 211, and a ring-shaped connection that integrally connects the inner sleeve 211 and the outer sleeve A sleeve member 210 having a portion 213 is prepared. The connecting portion 213 is provided at, for example, an intermediate portion in the longitudinal direction (left-right direction in FIG. 29) of the sleeve member 210. The position of the connecting portion 213 is not limited and may be the end portion of the sleeve member 210. The sleeve member 210 is integrally formed by casting or the like. The sleeve member 210 has two space portions 214 and 215 with the connecting portion 213 sandwiched between the inner sleeve 211 and the outer sleeve. The braided shield 12 is inserted into one space (space 214 in FIG. 29), and the metal pipe 11 is inserted into the other space (space 215 in FIG. 29) as described later.

  Next, the braided shield 12 is inserted into the space 214 of the sleeve member 210. The portion of the braided shield 12 inserted into the space 214 becomes the overlapping portion 222. Thereafter, a cylindrical jig 221 is inserted into the internal space 216 of the sleeve member 210 as shown in FIG. Thereafter, compression is performed by applying pressure from the outside of the outer sleeve 212 by a pressing means (for example, a jig) in the overlapping portion 222, and the outer sleeve 212, the braided shield 12, and the inner sleeve 211 are mechanically joined. . By this mechanical joining, a contact area between the braided shield 12 and the outer sleeve 212 and the inner sleeve 211 is secured, and electrical contact is increased. The compression molding is performed over the entire circumference of the sleeve member 210.

  Next, as shown in FIG. 31, a part of the overlapped portion 222 that has been mechanically joined is partially melted and solidified, and the braided shield 12, the outer sleeve 212, and the inner sleeve 211 in the partially melted and solidified portion 231 are formed. Fully electrically joined. Thereby, the cylindrical body 230 is obtained. This partial melting and solidification is performed by applying heat from the outside of the outer sleeve 212 by a technique such as TIG welding, MIG welding, electron beam welding, or laser welding.

  Next, as shown in FIG. 32, the metal pipe 11 is inserted into the space 215 of the sleeve member 210. The portion of the metal pipe 11 inserted into the space portion 215 becomes the overlapping portion 242. At this time, the electric wire main body 20 inserted in advance in the metal pipe 11 is inserted into the cylindrical body 230.

  Next, the boundary portion 241 between the cylindrical body 230 and the metal pipe 11 is melt-bonded by MIG welding or the like to form a melt-bonded portion 251 as shown in FIG. This fusion bonding is continuously performed over the entire circumference of the cylindrical body 230. As a result, the metal pipe 11 and the sleeve member 210 in the cylindrical body 230 are reliably electrically connected at the melt joint portion 251.

  Finally, the sleeve member 210 is insulated. For example, heat-shrinkable tubes each having a length that completely covers the sleeve member 210 are prepared, and after covering the sleeve member 210, hot blow is performed so that the heat-shrinkable tube is shrunk to be in close contact with the shield member. Do.

  According to the shielded wire using the cylindrical body 230, the braided shield 12 and the sleeve member 210 are electrically joined by direct contact, and the sleeve member 210 and the metal pipe 11 are electrically joined by direct contact. . That is, the braided shield 12 and the metal pipe 11 are indirectly electrically connected via the sleeve member 210. Here, since the braided shield 12 has a net-like porous structure, if spot welding is performed in a state where the braided shield 12 and the metal pipe 11 are in direct contact, the electrical contact at the welded portion is not very good. However, in the shielded electric wire using the cylindrical body 230, the braided shield 12 and the sleeve member 210, and the sleeve member 210 and the metal pipe 11 are electrically joined in a planar shape over a wide range. For this reason, by electrically connecting the braided shield 12 and the metal pipe 11 indirectly via the sleeve member 210, the electrical connection becomes more reliable.

  As described above, the present invention is not limited to the above-described embodiment, and it goes without saying that various other things are assumed.

1 is a plan view of a shielded electric wire according to a preferred embodiment of the present invention. FIG. 2 is a sectional view taken along line 2-2 of FIG. FIG. 3 is a sectional view taken along line 3-3 in FIG. 1. FIG. 4 is a sectional view taken along line 4-4 of FIG. FIG. 5 is a sectional view taken along line 5-5 of FIG. It is a top view of a cylinder. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. 6. It is sectional drawing which shows the state before giving compression molding to a cylinder. It is sectional drawing of the cylinder in compression molding. It is a top view of the cylinder after performing compression molding. It is the 11-11 line sectional view of FIG. It is a top view at the time of making the electric wire main body penetrate the metal pipe. It is a top view at the time of butting | matching the cylinder of FIG. 10 and the metal pipe of FIG. It is a top view at the time of connecting a cylinder and a metal pipe. It is a top view at the time of welding a cylinder and a metal pipe. It is a top view which shows the 1st modification of FIG. It is a top view at the time of welding a cylinder and a metal pipe after the connection of FIG. It is a top view which shows the 2nd modification of FIG. It is a top view at the time of welding a cylinder and a metal pipe after the connection of FIG. It is a top view which shows the 3rd modification of FIG. It is a top view at the time of welding a cylinder and a metal pipe after the connection of FIG. It is a top view after welding a cylinder and a metal pipe. It is a top view which shows the state which turned up the exposure shield when connecting a cylinder and a connector member. It is a top view which shows the state which returned the exposure shield. It is a top view which shows the state which covered the crimping ring on the exposure shield. It is a top view after giving compression molding to a pressure bonding ring. It is a top view at the time of welding a connector member and a crimping | compression-bonding ring. It is a top view which shows the state which coat | covered the insulation coating after welding. It is sectional drawing which shows the 1st modification of the shield member of FIG. It is sectional drawing at the time of performing a joining process to the shield member of FIG. It is sectional drawing after giving an electrical joining process to the shield member which performed the joining process. It is sectional drawing after connecting the shield member and metal pipe of FIG. It is sectional drawing after welding a shield member and a metal pipe. It is a top view of the conventional shielded electric wire. FIG. 35 is a sectional view taken along line 35-35 in FIG. 34. FIG. 36 is a sectional view taken along line 36-36 in FIG. 34.

Explanation of symbols

11 Metal pipe 12 Braided shield (cylinder)
15 Insulator 17 Conductor 20 Electric Wire Body 21 Inner Sleeve (Cylinder)
22 Outer sleeve (cylinder)
50 Tube 500 Connector member 502 Flange

Claims (3)

In a shielded electric wire provided with a wire body formed by coating a conductor made of a single wire or a stranded wire with an insulator, and a shield member provided on the outer periphery of the wire body,
The shield member is composed of a cylindrical body provided with a braided shield and an outer sleeve sequentially around the inner sleeve, and a metal pipe provided in abutment with the outer sleeve of the cylindrical body, and one end side of the cylindrical body is The shielded electric wire, wherein the outer sleeve and the metal pipe are electrically connected by fusion bonding, and the other end is electrically connected to a connector member having a flange portion. The braided shield of copper or a copper alloy, according to claim 1 Symbol placement of the shielded wire to constitute the metal pipe and the connector member of aluminum or aluminum alloy. The braided shield, the metal pipe, and the connector member, according to claim 1 Symbol placement of the shielded wire is constituted by aluminum or an aluminum alloy.

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