JP2007066574A - Shield conductor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a diameter of a shield conductor by preventing increase in a cross section of a conductor which results in enlargement of the diameter and increase in the weight of the shield conductor. <P>SOLUTION: The conductor 10 penetrating through a shield pipe 20 is provided with a terminal 15 at an end of a heat pipe 11, and heat generated when the conductor 10 is energized is released outside the heat pipe 11 by working fluid circulating in the heat pipe 11 while repeating evaporation and condensation. Because the nearly entire conductor 10 is formed of the heat pipe 11 having a superior heat radiation performance, the heat radiation efficiency of the whole conductor is superior compared to the example that a rod is connected to the end of the heat pipe, which allows the diameter of the whole conductor 10 to be reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a shield conductor.

As a shield conductor mounted on a vehicle such as an electric vehicle, a plurality of non-shielded electric wires are collectively shielded by being surrounded by a shield member made of a cylindrical braided wire in which fine metal wires are knitted in a mesh shape. The structure is considered. As a method for protecting the shield member and the electric wire in this type of shield conductor, generally, a means for surrounding the shield member with a protector made of synthetic resin is used, but there is a problem that the number of parts increases when the protector is used.
Therefore, the applicant of the present application has proposed a structure in which a non-shielded electric wire is inserted into a metal pipe as described in Patent Document 1. According to this structure, since the pipe exhibits the function of shielding the electric wire and the function of protecting the electric wire, there is an advantage that the number of parts can be reduced as compared with the shield conductor using the shield member and the protector.
JP 2004-171952 A

In shield conductors using pipes, there is an air layer between the wires and the pipe, so the heat generated in the wires when energized is blocked by the air with low thermal conductivity and is not easily transmitted to the pipes. Since the pipe does not have an external ventilation path such as a gap between stitches in the braided wire, the heat generated in the electric wire tends to be trapped inside the pipe and the heat dissipation tends to be low.
Here, the amount of heat generated when a predetermined current flows through the conductor decreases as the cross-sectional area of the conductor increases, and the temperature rise value of the conductor due to heat generation is suppressed as the heat dissipation of the conductive path increases. Therefore, in an environment where an upper limit is set for the temperature rise value of the conductor, in the case of a shield conductor with low heat dissipation efficiency as described above, it is necessary to increase the cross-sectional area of the conductor to suppress the amount of heat generation.
However, increasing the cross-sectional area of the conductor means that the shield conductor is increased in diameter and weighted, and a countermeasure is desired.
The present invention has been completed based on the above circumstances, and an object thereof is to reduce the diameter of a shield conductor.

  As a means for achieving the above object, the invention of claim 1 includes a shield pipe and a conductor penetrating the shield pipe and having an end connected to another conductive means. The conductor is characterized in that the terminal is provided at the end of the heat pipe.

  According to a second aspect of the present invention, the heat pipe according to the first aspect is configured such that a working fluid is sealed inside the metal pipe member by crushing and deforming and closing the end of the metal pipe member. And a terminal separate from the heat pipe is fixed to an end face of the metal tube material.

  The invention of claim 3 is characterized in that, in the invention of claim 1 or 2, the heat pipe is provided with a heat sink having heat radiation fins.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the heat radiating portion of the heat pipe can be attached to a vehicle body of an automobile, and the heat radiating portion is attached to the vehicle body. In the state attached to, it has the characteristics in the heat of the said heat radiating part being transmitted to the said vehicle body.

<Invention of Claim 1>
The heat generated when the heat pipe as a conductor is energized is released to the outside of the heat pipe as the working liquid circulates and moves in the heat pipe while repeating evaporation and condensation. In the present invention, the conductor itself has a heat dissipation function, and is superior in heat dissipation efficiency compared to the conductor that transmits heat to another heat dissipation member and releases it. Can be small.
As a form of the conductor using the heat pipe, it is possible to connect the base end of a metal bar to the end of the heat pipe and use the tip of the bar as a terminal. However, since the heat dissipation efficiency of the bar is lower than that of the heat pipe, it is necessary to make the bar larger than the diameter of the heat pipe in order to suppress heat generation, and as a result, the overall diameter of the conductor can be reduced. Disappear. In that respect, in the present invention, since the terminal is provided at the end of the heat pipe, almost the entire conductor is constituted by the heat pipe having high heat dissipation performance, so that the bar at the end of the heat pipe. Compared to the connection of the conductors, the heat dissipation efficiency of the entire conductor is excellent, and the diameter of the entire conductor can be reduced.

<Invention of Claim 2>
Since the closed portion of the end face of the heat pipe is covered with the terminal, the leakage of the working fluid in the heat pipe is surely prevented.

<Invention of Claim 3>
The heat generated in the heat pipe by energization is released into the atmosphere from the surface of the heat sink fin of the heat sink. According to the present invention, compared with the case where heat is radiated directly from the outer peripheral surface of the heat pipe to the atmosphere, the heat radiating area is large, so that the heat radiating efficiency is excellent.

<Invention of Claim 4>
In the present invention, focusing on the fact that the car body of an automobile can be used as an efficient heat radiator by utilizing an endothermic body and running wind having a large heat capacity, the heat radiation part of the heat pipe can be attached to the car body of the automobile. I made it. In a state where the heat radiating portion is attached to the vehicle body, the temperature gradient between the heat radiating portion and the vehicle body is maintained by the heat absorbing performance and heat radiating performance of the vehicle body, and heat is efficiently transferred from the heat radiating portion to the vehicle body side. Therefore, the heat dissipation efficiency is better than that of the means for releasing the heat of the heat dissipation part into the atmosphere.

<Embodiment 1>
A first embodiment of the present invention will be described below with reference to FIGS. An engine room is provided in the front part of a vehicle body Bd of an electric vehicle EV (a vehicle which is a constituent element of the present invention), and a device Ma (which constitutes a power circuit for driving the traveling motor Mo (in the engine room) For example, an inverter) and an engine Eg for driving gasoline are accommodated. A device Mb (for example, a battery) constituting a power circuit is mounted on the rear portion (for example, a trunk room) of the vehicle body Bd. A shield conductor Wa and an in-vehicle conductor Wb are routed between the two devices Ma and Mb.

  The shield conductor Wa includes three conductors 10 and a shield pipe 20 made of metal (for example, aluminum alloy, stainless steel, copper, copper alloy, etc.) having both a collective shield function and a conductor protection function. The conductor 10 is configured such that the terminal 15 is fixed to the front end portion of the heat pipe 11 and a connection member (not shown) is connected to the rear end portion of the heat pipe 11. The heat pipe 11 has a known structure in which a working fluid (for example, water) is sealed in a working space that is hermetically sealed inside, and the outer periphery of each heat pipe 11 is made of a synthetic resin. The insulating coating 12 is covered.

The heat pipe 11 is composed of a cylindrical metal tube 13, and a wick (not shown) for returning the working fluid moved to the low temperature side (heat dissipating part 16) of the heat pipe 11 to the high temperature side is provided on the inner periphery of the metal tube material 13. Z) is pasted. In manufacturing the heat pipe 11, first, the base end portion (lower end portion) of the metal tube 13 is hermetically sealed by reducing the diameter by a press, and a working fluid is injected into the metal tube 13; Then, the front-end | tip part (upper end part) of the heat pipe 11 is sealed airtightly by carrying out the diameter reduction deformation | transformation with a press. In addition, the insulating coating 12 is removed from the portion to be reduced in diameter, and a metal (for example, copper or copper alloy) sleeve 14 is fitted on the outer periphery thereof. The outer diameter of the sleeve 14 is substantially the same as the outer diameter of the majority of the area of the heat pipe 11 that is not deformed. Further, the front and rear end faces of the heat pipe 11 are flat surfaces perpendicular to the axis (length direction) of the heat pipe 11. The flat surface includes a circular portion formed by the end surface of the metal pipe member 13 that has been deformed to a reduced diameter, and an annular portion formed by the end surface of the sleeve 14 that concentrically surrounds the circle of the metal tube member 13. Although configured, the end surface of the circular portion formed by the metal tube 13 and the end surface of the annular portion formed by the sleeve 14 are flush with each other.
The three heat pipes 11 manufactured as described above are collectively penetrated by one shield pipe 20, and both front and rear ends of the heat pipe 11 are led out (projected) to the outside of the shield pipe 20.

  A terminal 15, which is a separate part from the heat pipe 11, is fixed to the front end of the heat pipe 11 so as to be conductive. The terminal 15 is made of metal (for example, copper, copper alloy, aluminum alloy, etc.), and has an elongated cylindrical shape as a whole. The front end portion of the terminal 15 has a hemispherical shape, and the rear end surface of the terminal 15 is a flat surface perpendicular to the axis of the terminal 15. The rear end surface of the terminal 15 is fixed to the front end surface of the heat pipe 11 so as to be conductive and concentrically by a cold welding method or the like. Further, since the outer diameter of the terminal 15 is the same as the outer diameter of the sleeve 14 (heat pipe 11), the outer peripheral surface of the terminal 15 and the outer peripheral surface of the sleeve 14 (heat pipe 11) are smoothly continuous.

  The front end portion of the conductor 10 is attached to the harness side connector 25. The harness-side connector 25 is formed by forming three cavities 27 in a male-side housing 26 made of synthetic resin. In each cavity 27, the front end portion of the conductor 10, that is, the terminal 15, and the front end portion of the heat pipe 11 are provided. Contained. A fitting recess 28 is formed at the front end of the male housing 26, and a substantially front half portion of the terminal 15 protrudes into the fitting recess 28.

On the other hand, as a means for connecting the in-vehicle conductor 10Wb to the shield conductor Wa at the rear end portion of the heat pipe 11, a metal rod-like connection having an open barrel-like crimping portion formed at the rear end portion. A front end portion of a member (not shown) is fixed coaxially so as to be conductive by cold welding or the like.
The in-vehicle conductor Wb encloses three flexible non-shielded electric wires (not shown) in a lump with a flexible shield member made of braided wire made of fine metal wires. A core wire made of a stranded wire that is exposed by peeling off the resin coating at the end of the electric wire of the in-vehicle conductor Wb is fixed to the crimping portion of the connecting member so as to be conductive by crimping. Further, the front end portion of the flexible shield member of the in-vehicle conductor Wb is connected to the rear end portion of the shield pipe 20 of the shield conductor Wa so as to be conductive.

  The shield conductor Wa is routed substantially horizontally along the floor under the vehicle body Bd (below the floor plate Fp). At both front and rear end portions of the shield conductor Wa, the front end portion of the shield pipe 20 is fixed to the vehicle body Bd by the bracket 21 in a suspended state. Of the front end side portion of the conductor 10 protruding from the shield pipe 20, a portion close to the shield pipe 20 is a heat radiating portion 16, and this heat radiating portion 16 is fixed to the outer surface (lower surface) of the floor board Fp by the heat sink 30. Yes. On the other hand, the in-vehicle conductor 10Wb connected to the rear end portion of the shield conductor Wa is routed in the vehicle through the floor plate Fp and connected to the device Mb.

Next, the heat sink 30 will be described.
The heat sink 30 includes a holding body 31 and a fixture 34.
The holding body 31 is made of a metal material having high thermal conductivity, and has a substantially rectangular shape (block shape). The holding body 31 is formed with three holding holes 32 penetrating in the front-rear direction. Each holding hole 32 has a heat radiating portion 16 that protrudes forward from the shield pipe 20 of the conductor 10, that is, in the heat pipe 11. The portion covered with the insulating coating 12 is penetrated. There is almost no gap between the outer periphery of the insulating coating 12 and the inner periphery of the holding hole 32. Further, a pair of ribs 33 are formed so as to protrude from the left and right side edges of the holding body 31.

  The fixture 34 is made of a metal plate, and has a substantially “U” -shaped covering portion 35 that is in surface contact with the lower surface of the holding body 31 and both left and right side surfaces, and extends from the left and right edges of the covering portion 35 to the lower surface of the rib 33. It consists of a pair of left and right support plate portions 36 that are in surface contact and a plate-like heat radiation fin 37 that extends substantially perpendicularly from the outer surface of the cover portion 35. A metal bolt 38 is passed through the support plate portion 36 of the fixture 34 from below. The bolt 38 passes through the rib 33 of the holding body 31 and is screwed into a female screw portion (not shown) of the floor board Fp. By fastening the bolt 38, the fixture 34, the holding body 31, and the heat pipe 11 are attached to the vehicle body Bd (floor plate Fp), and the upper surface of the holding body 31 and the rib 33 is in surface contact with the lower surface (outer surface) of the floor plate Fp. It is fixed with.

  In addition, a cylindrical front shield member 40 that collectively shields the three conductors 10 protruding forward from the heat sink 30 (holding body 31) is provided between the fixture 34 and the harness side connector 25. It has been. The rear end portion of the front shield member 40 is fixed to the front end surface of the holding body 31, and the front end portion of the front shield member 40 is a cylindrical shield shell (not shown) provided so as to surround the male housing 26. )It is connected to the. On the other hand, the rear end portion of the fixture 34 and the front end portion of the shield pipe 20 are connected to each other through a cylindrical rear shield member 41 that collectively surrounds the three conductors 10. .

A device-side connector 50 is provided in the device Ma. The device-side connector 50 includes a female-side housing 53 attached so as to penetrate the attachment hole 52 of the metal shield case 51 constituting the device, and a female terminal fitting 54 (in the present invention) accommodated in the female-side housing 53. Other conductive means which is a constituent requirement). A cylindrical elastic contact piece 56 is accommodated in the connection hole 55 of the female terminal fitting 54.
The harness side connector 25 is fitted to the device side connector 50. In the fitted state, the distal end portion of the female housing 53 of the device-side connector 50 is fitted into the fitting recess 28 of the harness-side connector 25, the terminal 15 is fitted into the connection hole 55 of the female terminal fitting 54, and the elastic contact piece 56 is in elastic contact with the outer periphery of the terminal 15, so that the terminal 15 and the female terminal fitting 54 are connected in a conductive manner. Further, the front end portion of the shield shell is connected to the shield case 51.

Next, the operation of this embodiment will be described.
When the conductor 10 is energized, the heat pipe 11 constituting the conductor 10 generates heat. If energization continues, the heat pipe 11 becomes hot inside the shield pipe 20 and the heat radiation part 16 of the heat pipe 11 located outside the front of the shield pipe 20 becomes a low temperature part, so the inside of the shield pipe 20 and the heat radiation part 16 A temperature gradient occurs between Then, the working fluid in the heat pipe 11 evaporates inside the shield pipe 20 to absorb latent heat, the vapor moves toward the heat radiating portion 16, the vapor condenses in the heat radiating portion 16 and releases latent heat, Return to the high temperature side as working fluid. By repeating this, the heat in the shield pipe 20 moves to the heat radiation part 16.

  Further, since the region in front of the heat radiating portion 16 of the conductor 10 is exposed to the outside of the shield pipe 20, the temperature rise is lower than the region surrounded by the shield pipe 20, but it is connected to the heat sink 30. The temperature is higher than that of the heat radiating part 16. Therefore, also in the region from the heat radiation part 16 (heat sink 30) to the terminal 15 in the conductor 10, the working fluid in the heat pipe 11 evaporates and absorbs latent heat, and the vapor moves toward the heat radiation part 16, The operation of repeatedly condensing steam in the heat radiating portion 16 to release latent heat and returning to the high temperature side as a working fluid is repeated, and the heat generated in front of the heat radiating portion 16 is also the heat generated in the shield pipe 20. Similarly, it moves to the heat radiation part 16.

  The heat moved to the heat radiating part 16 is transmitted from the outer surface of the heat radiating part 16 to the holding body 31 and moves inside the holding body 31. 2 and 3 of the holding body 31 is transferred to the metal floor plate Fp and spreads from the floor plate Fp to the entire vehicle body Bd. Further, the heat transferred to the lower surface of the holding body 31 in FIGS. 2 and 3 and the left and right side surfaces in FIG. 3 is transmitted to the fixture 34 and dissipated from the surface of the fixture 34 into the atmosphere, and from the fixture 34. It moves to the radiation fin 37 and is diffused into the atmosphere from the surface of the radiation fin 37.

  As described above, in the present embodiment, the heat generated when the conductor 10 is energized moves to the heat radiating section 16 by circulating the working fluid in the heat pipe 11 while repeating evaporation and condensation. Is to be released from. Thus, the conductor 10 itself has a heat dissipation function, and is superior in heat dissipation efficiency compared to the conductor 10 that transmits heat to another heat dissipation part 16 material and releases it. That is, the outer diameter can be reduced.

  Moreover, as a form of the conductor using the heat pipe, it is possible to connect the base end of a metal bar to the end of the heat pipe and use the tip of the bar as a terminal. Since the heat dissipation efficiency of the bar material is lower than that of the heat pipe, it is necessary to make the bar material have a larger diameter than the heat pipe in order to suppress heat generation. Can not be. In that respect, in this embodiment, since the terminal 15 is provided at the end of the heat pipe 11, almost the entire conductor 10 is configured by the heat pipe 11 having high heat dissipation performance. Compared with the case where a bar is connected to the end, the heat dissipation efficiency of the entire conductor 10 is excellent, and the diameter of the entire conductor 10 can be reduced.

  Moreover, since the heat sink 30 having the heat radiation fins 37 is provided in the heat radiation part 16 of the heat pipe 11, the heat generated in the heat pipe 11 by energization is released from the surface of the heat radiation fin 37 of the heat sink 30 to the atmosphere. The That is, according to this embodiment, since the heat radiation area is wide, the heat radiation efficiency is superior to the case where heat is radiated directly from the outer peripheral surface of the heat pipe 11 to the atmosphere.

  Further, paying attention to the fact that the vehicle body Bd of an automobile can be used as a heat absorber and a heat radiator having a large heat capacity, the heat radiation portion 16 of the heat pipe 11 is attached to the floor plate Fp of the vehicle body Bd. In a state in which the heat radiating part 16 is attached to the vehicle body Bd, the temperature gradient between the heat radiating part 16 and the vehicle body Bd is maintained by the heat radiating performance of the car body Bd, and heat is efficiently transmitted from the heat radiating part 16 to the vehicle body Bd side. Is transmitted to. Therefore, the heat radiation efficiency is better than the means for releasing the heat of the heat radiation portion 16 into the atmosphere.

  In addition, the heat pipe 11 is configured such that the working fluid is sealed inside the metal tube 13 by crushing and deforming and closing the end of the metal tube 13, but on the end surface of the metal tube 13, Since the terminal 15 separate from the heat pipe 11 is fixed, the closed portion (front end surface) of the end of the heat pipe 11 is covered with the terminal 15 (rear end surface). Thereby, the leakage of the working fluid in the heat pipe 11 is reliably prevented.

<Other embodiments>
The present invention is not limited to the embodiment described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.
(1) Although the heat sink is provided in the heat radiating part of the heat pipe in the above embodiment, according to the present invention, heat may be released from the heat radiating part to the atmosphere without providing such a heat sink.
(2) In the above embodiment, three heat pipes are inserted into one shield pipe, but according to the present invention, the number of heat pipes inserted into one shield pipe is one, two, and four. Any of the above may be used.
(3) In the above embodiment, the heat of the heat radiating portion of the heat pipe is transmitted to the vehicle body. However, according to the present invention, the heat of the heat radiating portion may be transmitted to the conductor of the in-vehicle conductor. You may make it discharge | release to air | atmosphere from a part.
(4) In the above embodiment, the wick is attached to the inner periphery of the heat pipe (metal pipe material). However, according to the present invention, the wick may not be provided.
(5) In the above embodiment, the terminal is a separate component from the heat pipe, but according to the present invention, the end of the heat pipe may be the terminal.
(6) In the above embodiment, the terminal covers the closed portion of the end portion of the heat pipe. However, according to the present invention, the terminal may not cover the closed portion of the end portion of the heat pipe.
(7) In the above embodiment, the terminal is male, but according to the present invention, the terminal may be female.
(8) In the above embodiment, the heat pipe is provided with the heat sink having the radiation fins. However, according to the present invention, the water-cooled pipe may be brought into contact with the heat pipe instead of the heat sink or along the heat pipe. A water-cooled pipe may be provided inside the heat sink.
(9) In the above embodiment, the end of the shield conductor is connected to the device-side connector, but the present invention can also be applied to the case where the end of the shield conductor is connected to another harness.

Overall view of Embodiment 1 Partial enlarged sectional view showing the mounting part for the car body XX sectional view of FIG. Partial enlarged sectional view showing the end of the heat pipe

Explanation of symbols

Bd ... Body Ev ... Electric car (car)
Wa ... Shield conductor 10 ... Conductor 11 ... Heat pipe 15 ... Terminal 20 ... Shield pipe 30 ... Heat sink 37 ... Radiation fin 54 ... Female terminal fitting (other conductive means)

Claims (4)

A shield pipe,
A conductor penetrating through the shield pipe and having a terminal connected to another conductive means;
The shield conductor is characterized in that the terminal is provided at an end of a heat pipe. The heat pipe is configured to enclose a working fluid inside the metal tube material by crushing and closing the end of the metal tube material,
The shield conductor according to claim 1, wherein a terminal separate from the heat pipe is fixed to an end face of the metal pipe member. The shield conductor according to claim 1, wherein the heat pipe is provided with a heat sink having a radiation fin. The heat dissipation part of the heat pipe can be attached to the body of an automobile,
The shield conductor according to any one of claims 1 to 3, wherein heat of the heat dissipation portion is transmitted to the vehicle body in a state where the heat dissipation portion is attached to the vehicle body. .

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