JP2009135240A - Shield structure of electric wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shield structure of electric wires, which has superior heat dissipation characteristics, can be manufactured at low cost, and hardly interferes with other devices mounted on a vehicle or the surface of the ground on which the vehicle is traveling when fitted to, for example, the vehicle body. <P>SOLUTION: Disclosed is the shield structure of the electric wires including: a plurality of the electric wires 11 and 12 electrically connecting electric devices 101 and 102 to each other; and metal pipes 21 and 22 individually covering the plurality of the electric wires 11 and 12. Consequently, the shield structure of the electric wires has superior heat dissipation characteristics, can be manufactured at low cost, hardly interferes with other mounted devices on the vehicle when fitted to the vehicle body, and is less likely to come into contact with the surface of the ground during a travel of the vehicle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a shield structure for an electric wire that covers the electric wire and prevents electromagnetic noise due to the high-frequency current of the electric wire from adversely affecting the surroundings.

  In general, it is known that electromagnetic noise due to high-frequency current is generated from a wire harness (electric wire) that supplies a motor driving current of a hybrid vehicle. Various types of shield structures for electric wires have been proposed in the past to shield the electromagnetic noise and prevent the noise from being superimposed on signal lines of an ECU (Electric Control Unit) or the like (for example, (See Patent Document 1 and Patent Document 2).

  The electric wire shield structure described in Patent Document 1 uses a traveling wind of a vehicle by putting a plurality of electric wires together and inserting them into one metal pipe, and attaching the metal pipe along the lower surface of the floor panel of the vehicle body. The heat generated by the wires is dissipated.

On the other hand, the electric wire shield structure described in Patent Document 2 has a structure in which a plurality of electric wires are collectively inserted into one metal pipe and a space between the electric wire and the metal pipe is filled with a heat transfer material having high thermal conductivity. As a result, the heat generated in the electric wire is transmitted to the pipe via this heat transfer body to be radiated into the air.
JP 2007-8423 (paragraph (0016), FIG. 3) Japanese Patent Laying-Open No. 2007-109642 (paragraphs (0019), (0021), FIG. 2)

  According to the shield structure of the electric wire described in Patent Document 1 described above, since a plurality of electric wires are combined and passed through a single metal pipe, heat generated from the electric wire is easily trapped in the pipe, and heat dissipation is achieved. There is a problem that is bad.

  Moreover, in the shield structure of the electric wire described in Patent Document 1, the diameter of the metal pipe is considerably increased. This is because the heat generated by collecting multiple wires increases, and heat is trapped in the metal pipe. Therefore, the diameter of the metal pipe is structurally increased in order to improve heat dissipation and protect the sheath of the wire. This is because it must be quite large. For this reason, when the metal pipe is attached to the lower surface of the floor panel of the vehicle body, the lower end of the metal pipe is close to the ground, and the lower end of the metal pipe may be grounded and damaged during traveling.

  FIG. 6 is a cross-sectional view showing a conventional electric wire shield structure in which three electric wires 11 to 13 are collectively covered with one metal pipe 80 along a plane perpendicular to the longitudinal direction of the metal pipe. As is apparent from this figure, it is understood that the diameter D of the metal pipe 80 becomes considerably large when the three electric wires 11 to 13 are collected and covered with the single metal pipe 80.

  On the other hand, according to the shield structure of the electric wire described in Patent Document 2, the heat dissipation in the metal pipe can be improved. However, after a plurality of electric wires are collectively inserted into one metal pipe, the heat transfer body is made of metal. Since a special process for filling the pipe without gaps is required, there is a problem that the manufacturing cost is increased.

  An object of the present invention is an electric wire shield structure that is excellent in heat dissipation and can be manufactured at low cost, for example, less likely to interfere with other on-vehicle equipment when attached to a vehicle body, and less likely to contact the ground while the vehicle is running. Is to provide.

  In order to solve the above-mentioned problem, a shield structure for an electric wire according to claim 1 of the present invention includes a plurality of electric wires that electrically connect electric devices, and a metal pipe that individually covers the plurality of electric wires. It is characterized by having.

  According to the first aspect of the present invention, it is not necessary to adopt a structure in which a plurality of electric wires are collectively inserted into a single metal pipe as in the conventional electric wire shield structure, so that the amount of heat generated in the metal pipe is suppressed. be able to. And heat generation of the electric wire put together like the conventional metal pipe does not remain in one metal pipe, and it becomes impossible to radiate heat, and can improve heat dissipation.

  In addition, since the metal pipe covers each electric wire, the diameter of each metal pipe can be reduced. Thereby, the thickness of the installation space of the metal pipe can be reduced. In particular, for example, when a metal pipe is attached to the lower surface of the floor panel of the vehicle body, a sufficient space can be secured between the lower end of the metal pipe and the ground.

  In addition, since the amount of heat generated in each metal pipe is the amount of heat generated by one electric wire, the amount of energization of each wire is reduced, the energization time is shortened, and the thickness of the wire is reduced as in the conventional shield structure. It is not necessary to take measures to reduce the usage specifications, such as reducing the resistance value by increasing the thickness of the wire, or to incur high costs, such as increasing the heat-resistant temperature of the sheath of the wire.

  In addition, an extra process that increases the cost, such as filling a gap between the electric wire and the metal pipe without changing the electric wire itself, is not required.

  The electric wire shield structure according to claim 2 of the present invention is characterized in that, in the electric wire shield structure according to claim 1, at least a part of the metal pipe is formed in a bellows shape.

  According to invention of Claim 2, since the surface area of a metal pipe can be made larger than a mere straight pipe, heat dissipation can be improved more. In particular, for example, when a metal pipe is attached to the lower surface of the floor panel of the vehicle body, the surface area of the bellows portion of the metal pipe can be increased, so that the running wind during running can be received by this bellows portion to improve heat dissipation.

  The electric wire shield structure according to claim 3 of the present invention is characterized in that in the electric wire shield structure according to claim 1 or claim 2, the electric wire shield structure has a spacer for arranging the metal pipes at a predetermined interval. Yes.

  According to the third aspect of the present invention, the heat of each metal pipe is not transferred to the adjacent metal pipe but is radiated to the atmosphere, so that the heat dissipation can be further improved.

  In particular, for example, when metal pipes are attached to the vehicle body, they can be fixed to the vehicle body with the metal pipes separated from each other, so that heat generated by the electric wires in the metal pipes can be efficiently radiated using the traveling wind of the vehicle. Can do.

  Further, by attaching such a spacer to the metal pipe, it is possible to avoid breakage and abnormal noise due to interference between the metal pipes.

  An electric wire shield structure according to claim 4 of the present invention is the electric wire shield structure according to claim 3, wherein the electric device is mounted on a vehicle, and the spacer includes the metal pipe. It is configured as a bracket that can be fixed to a vehicle body on which the electric device is mounted.

  According to the fourth aspect of the present invention, the spacer can be provided with a bracket function, and a reduction in the number of parts can be achieved when the shield structure of the electric wire is applied to the vehicle.

  The electric wire shield structure according to claim 5 of the present invention is the electric wire shield structure according to any one of claims 1 to 4, wherein the spacer is made of a conductive member. It is said.

  According to the invention described in claim 5, the spacer serves as both a role of a bracket that is attached to the vehicle body in a state where the metal pipes are separated from each other, and a role of an earth for grounding each metal pipe to the vehicle body. It is possible to reduce man-hours when attaching the pipe to the vehicle body.

  In addition, by using a spacer that also serves as a bracket as a conductive member, grounding from the metal pipe to the vehicle body can be performed not only at both ends of the metal pipe but also at the attachment parts to the vehicle body, and a metal having a shielding function. The reliability of the pipe ground connection is improved.

  Moreover, the shield structure of the electric wire which concerns on Claim 6 of this invention is connected to the said electric equipment of the said some electric wire in the shield structure of the electric wire of Claim 1 of any one of Claim 1 thru | or 5. At least one of the terminal portions is characterized in that it is surrounded by a conductive member instead of individual metal pipes.

  According to the invention described in claim 6, when connecting the terminal portions of the plurality of electric wires to the electric device, it is not necessary to individually connect each metal pipe to the electric device, so that the connection workability is improved. .

  According to the present invention, it is possible to manufacture a wire shield structure that is excellent in heat dissipation and can be manufactured at low cost, for example, when it is attached to a vehicle body, hardly interferes with equipment mounted on other vehicles, and does not easily contact the ground while the vehicle is running. Can be provided.

  Hereinafter, the shield structure of the electric wire concerning one embodiment of the present invention is explained based on a drawing. In this embodiment, a case will be described in which the wire shield structure according to the present invention is applied to a vehicle, particularly a vehicle in which a wire harness for passing a large current such as a hybrid car is routed.

  1 and 2 are diagrams showing a shield structure of an electric wire in which two electric wires are individually covered with metal pipes, and FIGS. 3 and 4 are electric wires in which three electric wires are covered with metal pipes, respectively. However, since the essential parts according to the present invention are common, the components in each figure will be described with the same reference numerals.

  As shown in FIG. 1, the electric wire shield structure according to the present embodiment electrically connects a battery 101, which is an electric device provided in a trunk room of a hybrid car, and an inverter 102, which is an electric device provided in an engine room. A plurality (two in the embodiment shown in FIG. 1) of electric wires 11, 12 (10) and a plurality of (two in the embodiment shown in FIG. 1) metal pipes 21, 22 (20) individually covering the plurality of electric wires. ). The metal pipe 20 is made of a material having excellent conductivity, heat transfer, and heat dissipation, such as an aluminum alloy. In addition, the diameter of the metal pipe 20 is such that a certain gap is generated between the metal pipe 20 and the electric wire 10. Further, bellows-like portions 21a and 22a (20a) are formed on at least a part of the metal pipe 20 as shown in FIG.

  Further, as shown in FIG. 1, the metal pipe 20 is fixed to the lower surface of the floor panel of the vehicle body via brackets 31, 32, 33 (30) made of metal and fasteners 91, 92, 93 such as bolts. . The metal pipes are attached to the lower surface of the floor panel of the vehicle body via spacers 41 and 42 (40) at a predetermined interval.

  FIG. 3 is a cross-sectional view related to the wire shield structure shown by the solid line in FIG. In FIG. 3, it is sectional drawing explaining the shield structure (refer three metal pipes 21, 22, and 23 shown with a dashed-two dotted line) which connects the inverter 102 and the three-phase AC motor 103 which are shown in FIG. The electric wire shield structure in which the three electric wires 11, 12, 13 (10) are individually covered with the metal pipes 21, 22, 23 (20), respectively, is shown in a cross section along a plane perpendicular to the longitudinal direction of the metal pipe 20. Yes. As can be seen from FIG. 3, each electric wire 10 is covered with a metal pipe 20, and it can be seen that the metal pipes 20 are spaced apart from each other by a spacer (not shown).

  FIG. 4 is a perspective view of a spacer 40 for attaching the three metal pipes 20 shown in FIG. 3 at a predetermined interval. At both ends of the spacer 40, mounting holes 40a for attaching the spacer 40 to the floor panel of the vehicle body with fasteners such as bolts are formed.

  In the present embodiment, the spacer 40 is made of an aluminum alloy. However, as shown in FIG. 1, when each metal pipe 20 is grounded to the floor panel of the vehicle body via the metal bracket 30, the spacer 40 does not necessarily have to be made of a metal such as an aluminum alloy. It may be resinous.

  The bracket 30 is made of a metal or a resin material having excellent conductivity, and is fastened to the metal pipe 20 by a fastener not shown in detail here, and the bottom surface of the floor panel of the vehicle body via bolts 91, 92, 93. It is fixed to. The bracket 30 also serves to connect the metal pipe 20 and the floor panel of the vehicle body and to ground the metal pipe 20 to the floor panel of the vehicle body.

  The connection side end of the metal pipe 20 with the inverter 102 connects the metal pipes 21 and 22 directly to the inverter 102 as shown in FIG. Instead, they are connected by a braided wire 51 that collectively covers the ends of the metal pipes 21 and 22 and the inverter 102. The braided wire 51 is a cylindrical shield member in which metal fine wires are knitted in a mesh shape.

  When the braided wire 51 is fixed to the metal pipes 21 and 22 and the inverter 102, the number of fixing operations can be reduced by using a metal fastening band or the like. The braided wire 51 is entirely covered with a rubber cover (not shown) to ensure waterproofness.

  On the other hand, the end of the metal pipes 21 and 22 connected to the battery 101 does not directly connect the metal pipes 21 and 22 to the battery 101 as shown in FIG. 101 are connected by metal braided wires 52 and 53 that individually cover each other.

  When the braided wires 52 and 53 are fixed to the metal pipes 21 and 22 and the battery 101, if a metal fastening band or the like is used as in the case of the braided wire 51, the number of fixing steps can be reduced. The braided wires 52 and 53 are also covered with a rubber cover (not shown) to ensure waterproofness.

  Since the electric wire shield structure according to the present embodiment has the above-described configuration, it is not necessary to adopt a structure in which a plurality of electric wires are collectively inserted into one metal pipe as in the conventional electric wire shield structure. The diameter of the pipe 20 can be reduced (see the comparison between the diameter d of the metal pipe 20 of the present embodiment shown in FIG. 3 and the diameter D of the conventional metal pipe 80 shown in FIG. 6). Thereby, the thickness of the installation space of the metal pipe can be reduced. In particular, for example, when the metal pipe 20 is attached to the lower surface of the floor panel of the vehicle body, a sufficient space can be secured between the lower end of the metal pipe 20 and the ground.

  In addition, since the amount of heat generated in each metal pipe is the amount of heat generated by one wire, the amount of current flowing through each wire can be reduced as in the conventional shield structure of wires, the time required for electricity can be shortened, There is no need to take measures such as increasing the thickness to reduce the resistance value or increasing the heat-resistant temperature of the sheath of the wire.

  In addition, no measures are required to increase costs, such as filling the gap between the wire and the metal pipe without changing the wire itself.

  Further, since at least a part of the metal pipe 20 is formed in a bellows shape, the surface area of the bellows-like portion 20a of the metal pipe 20 can be increased, so that the metal pipe 20 is attached to the lower surface of the floor panel of the vehicle body. In this case, the traveling wind during traveling can be received by the bellows-shaped portion 20a to improve heat dissipation.

  Moreover, by having the spacer 40 which arrange | positions metal pipes at fixed intervals, since the heat | fever of each metal pipe 20 is not transmitted to the adjacent metal pipe 20 but is radiated to air | atmosphere, it can improve heat dissipation more. it can. When the metal pipe 20 is attached to the vehicle body, the metal pipe 20 can be fixed to the vehicle body in a state where the metal pipes are separated from each other, so that the heat generated by the electric wire in the metal pipe can be efficiently radiated using the traveling wind of the vehicle. Can do. Further, by attaching the spacer 40 to the metal pipe 20, it is possible to avoid damage and noise generation due to interference between the metal pipes.

  Further, the terminal portions of the electric wires 11 and 12 are collectively surrounded by a braided wire 51 made of a conductive member instead of the individual metal pipes 21 and 22, so that the terminal portions of the electric wires 11 and 12 are connected to the inverter. The connection workability is improved because it is not necessary to individually connect the metal pipes 21 and 22 to the inverter 102 when connecting to the inverter 102.

  The spacer 40 may be made of metal or conductive resin, and may be fixed in a state where the metal pipe 20 is electrically connected to the lower surface of the floor panel of the vehicle body on which the electric device is mounted. Thus, the spacer 40 serves as the bracket 30, and the metal pipes are separated from each other to improve the heat dissipation of each metal pipe 20, and the metal pipe 20 can be electrically grounded (grounded) to the floor panel of the vehicle body. it can. Moreover, the attachment property at the time of attaching the metal pipe 20 to a vehicle body can be aimed at.

  The ends of the electric wires 11 and 12 connected to the inverter 102 are collectively covered with a braided wire 51 instead of the individual metal pipes 20, and the end of each metal pipe 20 and the inverter 102 are connected to the braided wire 51. It is not always necessary to be electrically connected via the cable, but having such a structure improves the assembly of the shield structure of the electric wire, for example, on the conveyor of the vehicle assembly line. The tact time related to this process can be shortened in connection work.

  Moreover, the bellows-shaped part 20a may be formed in a part of metal pipe 20, and may be formed over the full length. In addition, the bellows-shaped part 20a may be formed by continuing the corrugated cross-section in the longitudinal direction of the metal pipe 20, or the recess may be formed in a spiral shape on the peripheral surface of the metal pipe. Good.

  Further, instead of covering the electric wires 11 and 12 with the braided wires 52 and 53 on the motor 101 side, the electric wires 11 and 12 may be covered together like the braided wire 51.

  Further, the material of the metal pipe 20 is an aluminum alloy that is light in weight and excellent in cost and assembly in the above-described embodiment, but is made of a metal such as stainless steel or a titanium alloy when corrosion resistance is required. May be.

  When the electric wire shield structure according to the present invention is applied to, for example, a hybrid car, the connection is not limited to the connection between the battery 101 and the inverter 102 shown in FIG. 1, but the inverter 102 and the three-dot line shown in FIG. The present invention can also be applied to a shield structure of three wires between the AC motor 103 and the phase AC motor 103.

  However, in order to electrically connect the battery 101 mounted in the trunk room and the inverter 102 mounted in the engine room as shown in FIG. 1, the shield structure of the electric wire in which the metal pipe 20 is attached to the lower surface of the floor panel. In this case, since the total length of the electric wire is long and heat tends to be accumulated at the central portion in the longitudinal direction of the metal pipe 20 covering the electric wire, it is difficult to dissipate the heat. Compared with the case of a shield structure for an electric wire covering this with a pipe, the effect of heat dissipation can be further exhibited.

It is explanatory drawing which shows the shield structure of the electric wire concerning one Embodiment of this invention. FIG. 2 is a cross-sectional view taken along a longitudinal direction of a portion of a metal pipe having a bellows shape in the electric wire shield structure shown in FIG. 1. It is sectional drawing at the time of covering the three electric wires corresponding to the shield structure of the electric wire shown in FIG. 1 with a metal pipe, respectively. It is a perspective view of the spacer applicable to the shield structure of the three electric wires shown in FIG. It is the elements on larger scale of the shield structure of three electric wires corresponding to the inverter side edge part of the metal pipe shown in FIG. It is sectional drawing along the perpendicular | vertical surface with respect to the longitudinal direction of the metal pipe which shows an example of the shield structure of the conventional electric wire.

Explanation of symbols

10 (11, 12, 13) Electric wire 20 (21, 22) Metal pipe 20a (21a, 22a) Bellows portion 30 (31, 32, 33) Bracket 40 (41, 42) Spacer 40a Mounting hole 51, 52, 53 Braided wire 80 Metal pipe 91, 92, 93 Fastener 101 Battery 102 Inverter 103 Three-phase AC motor

Claims (6)

  An electric wire shielding structure comprising: a plurality of electric wires that electrically connect electric devices; and a metal pipe that individually covers the plurality of electric wires.   The wire shield structure according to claim 1, wherein at least a part of the metal pipe is formed in a bellows shape.   The wire shield structure according to claim 1, further comprising a spacer that holds the metal pipes at a predetermined interval.   The electric device is an electric device mounted on a vehicle, and the spacer is configured as a bracket capable of fixing the metal pipe to a vehicle body on which the electric device is mounted. Wire shield structure.   The said spacer consists of an electroconductive member, The shield structure of the electric wire of Claim 4 characterized by the above-mentioned. The at least one terminal portion connected to the electric device of the plurality of electric wires is collectively surrounded by a conductive member instead of individual metal pipes. The shield structure for an electric wire according to claim 1.

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