JP2006136147A - Heat dissipating structure, heat dissipation method and heat dissipating box - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique which can obtain a high heat dissipation effect using a simple structure and can reduce the pattern width of wiring, in a heat dissipation structure and a heat dissipation method which dissipate to the outside the heat of an electrical junction box provided with a wiring board in a junction-box body using a heat dissipating member which is partially exposed to the outside of the electric junction box. <P>SOLUTION: A first copper plate 41 is in contact with the rear surface of a first wiring board 31. A second copper plate 42 is provided between the rear surface of a second wiring board 32 and the rear surface of a third wiring board 33, the upper surface of the second copper plate 42 is in contact with the rear surface of the second wiring board 32, and the lower surface of the second copper plate 42 is in contact with the rear surface of the third wiring board 33. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat dissipation structure, a heat dissipation method, and a heat dissipation box for releasing heat generated inside an electric junction box used for in-vehicle wiring of an automobile to the outside.

In recent years, with the increase in electrical components of automobiles, there is a problem that the circuit density in the electrical junction box increases, circuit components such as fuses, coils, and relays increase, and the internal temperature of the electrical junction box increases.
In view of this, a technique has been provided in which a metal core is inserted between wiring boards and heat inside the electrical junction box is released by a heat pipe. (See Patent Document 1).
In addition, a technique is provided in which a heat sink is brought into contact with an upper surface of a circuit component via a connector to release heat (see Patent Document 2).
JP 2003-75082 A JP 2002-290086 A

However, the above prior art has the following problems.
Even in the invention described in Patent Document 1, since the heat generation from the circuit components mounted on the substrate is high, a metal core is inserted between the wiring boards, and heat is released with a heat pipe, so that the corresponding pattern width is suppressed. When the wiring is short-circuited, an overcurrent flows and the substrate may be melted before the fuse is blown, and there is a limit to reducing the wiring pattern width. Further, since the terminal comes out from the substrate, it cannot be brought into close contact with the substrate and is embossed on the metal side. Therefore, the thickness of the metal part becomes hot, and since it is concentrated on one surface, it is difficult to reduce the size of the heat dissipation area, and thus it is necessary to use a working fluid by a heat pipe.
Even in the invention described in Patent Document 2, when the wiring is short-circuited as described above, there is a limit to reducing the wiring pattern width because the substrate may be blown before an overcurrent flows and the fuse is blown. .
The present invention has been made in view of such problems, and an object thereof is to provide a technique capable of solving the above problems.

In order to solve the above problems, the present invention has the following configurations.
The gist of the invention described in claim 1 is a heat dissipation structure for releasing the heat of an electrical connection box having a wiring board therein by a heat dissipation member partially exposed to the outside of the electrical connection box, In the heat dissipation structure, the first heat conducting member is in contact with the wiring board, and the heat dissipating member is in contact with the first heat conducting member.
The gist of the invention of claim 2 is that the wiring boards are plural, the plural wiring boards are laminated,
The heat dissipation structure according to claim 1, wherein the first heat conducting member is in contact with a plurality of the wiring boards.
The gist of the invention described in claim 3 resides in the heat dissipation structure according to claim 1 or 2, wherein an insulating member is provided between a wiring surface of the wiring board and the first heat conducting member. .
The gist of the invention according to claim 4 resides in the heat dissipation structure according to any one of claims 1 to 3, wherein one of the first heat conducting members is in contact with the plurality of wiring boards.
The gist of the invention according to claim 5 is that the second heat conducting member is in contact with the heat radiating member, and a part of the first heat conducting member is bent to form a bent portion, and the bent portion is the second bent portion. 5. The heat dissipating structure according to claim 1, wherein the heat dissipating structure is in contact with the heat conducting member.
The gist of the invention described in claim 6 resides in the heat dissipating structure according to claim 5, wherein the bent portion is located at the periphery of the wiring board.
The gist of the invention of claim 7 is that a plurality of the first heat conducting members are provided, and a plurality of the first heat conducting members are provided in a state where the wiring board and the plurality of first heat conducting members are laminated. 6. The heat dissipation structure according to claim 5, wherein each of the bent portions surrounds an outer edge of the wiring board.
The gist of the invention described in claim 8 is that the circuit board is provided with a circuit component, and the circuit component is in contact with the heat dissipation member. Lies in the structure.
The gist of the invention of claim 9 is a heat radiating box provided with a wiring board inside, comprising an upper case and a lower case fitted to the upper case, wherein the upper case is provided with a heat radiating member, The lower case is provided with a first heat conducting member in contact with the wiring board.

Since this invention is comprised as mentioned above, there exists an effect hung up below.
By providing the heat conducting member in contact with the back surface (surface opposite to the wiring surface) of the wiring board and bringing the heat radiating member into contact with the heat conducting member, a high heat radiating effect can be obtained with a simple configuration. Compared with the prior art, the wiring pattern width can be made finer, and it is not necessary to provide a heat pipe.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same numerals are given to the same component.
As shown in FIG. 1, the electrical junction box 1 according to the present embodiment is used for in-vehicle wiring of an automobile, and is mainly composed of a synthetic resin case portion 10 and a cooling fin 20 (comb shape). Heat dissipating member). The case portion 10 is a combination of an upper case 11 and a lower case 12. The upper case 11 has an opening 11a through which the cooling fin 20 is inserted, and the cooling fin 20 is exposed to the outside from the opening 11a. The upper case 11 is formed with a plurality of housings 11b.
As shown in FIGS. 2 and 3, the inside of the case portion 10 has a hierarchical structure in which the first wiring board 31, the second wiring board 32, and the third wiring board 33 are sequentially located from the top. Yes.
The first wiring board 31 (wiring board) is a normal wiring board used for wiring for automobiles, and is formed by providing a first bus bar 31b on a first substrate 31a made of an insulating material such as ABS resin. Similarly, the second wiring board 32 (wiring board) and the third wiring board 33 (wiring board) are provided with the second bus bar 32b and the third bus bar 33b on the second board 32a and the third board 33a.
The first wiring board 31 and the second wiring board 32 are provided with the wiring surface (the surface on which the first bus bar 31b and the second bus bar 32b are provided) positioned on the upper side, and the third wiring board 33 has the wiring surface on the lower side. It is provided in the position.
As shown in FIG. 4, a first elongated hole 31 c and a second elongated hole 31 d are provided on the periphery of the first wiring board 31. A plurality of first terminals 31 e are provided on the upper surface of the first wiring board 31. The first terminal 31e is connected to a terminal of an electrical component such as a fuse inserted into a housing 11b formed in the upper case 11 shown in FIG.
As shown in FIG. 5, the second elongated board 32d and a plurality of second terminals 32e are also provided on the upper surface of the second wiring board 32 in the same manner.
Similarly, a third terminal 33 e shown in FIG. 8 is provided on the lower surface of the third wiring board 33.

As shown in FIG. 3, the first copper plate 41 (first heat conducting member) is in contact with the back surface of the first wiring board 31. A second copper plate 42 (first heat conducting member) is provided between the back surface of the second wiring board 32 and the back surface of the third wiring board 33. The upper surface of the second copper plate 42 is in contact with the back surface of the second wiring board 32, and the lower surface of the second copper plate 42 is in contact with the back surface of the third wiring board 33.
As shown in FIG. 6, the first copper plate 41 has a plurality of first insertion portions 41a. Moreover, the 1st copper plate 41 has the some 1st bending part 41b (bending part) of the square plate shape which stood and bent upwards at the periphery.
As shown in FIG. 7, the second copper plate 42 similarly has a plurality of second insertion portions 42 a and second bent portions 42 b (bent portions).
As shown in FIG. 8, when the first wiring board 31, the first copper board 41, the insulating sheet 50 (insulating member), the second wiring board 32, and the second copper board 42 are overlapped, the first bent portion 41b. Is inserted into the first elongated hole 31c and protrudes upward, and the second bent portion 42b is inserted into the second elongated hole 31d and the second elongated hole 32d shown in FIG. 5 and protrudes upward. The first bent portion 41b and the second bent portion 42b are positioned in a line alternately along the periphery of the first wiring board 31 when viewed from above. As a result, the circuit component 60 is surrounded by the first bent portion 41b and the second bent portion 42b (the configuration according to claim 7).

As shown in FIGS. 2 and 3, an insulating sheet 50 is provided between the wiring surface of the second wiring board 32 and the first copper plate 41. The insulating sheet 50 is made of a material excellent in thermal conductivity and insulation, such as a polymer film (polyester or the like).

A circuit component 60 is provided at the top of the hierarchical structure described above. The circuit component 60 is a normal coil, relay, or the like used for automobile wiring.

As shown in FIGS. 2 and 9, a lid copper plate 70 (second heat conducting member) is provided above the inside of the case portion 10. The lid copper plate 70 includes an upper surface on which the cooling fins 20 are provided by bonding and screwing with a heat conductive adhesive, and a side surface formed by bending downward.
The lid copper plate 70 is formed with a terminal hole 70a through which the first terminal 31e shown in FIG. 8 is inserted.
A screw hole 70 b is provided on the upper surface of the lid copper plate 70. The lid copper plate 70 is fixed inside the case portion 10 by being screwed in the screw holes 70b. At this time, the cooling fin 20 is inserted through the opening 11a. The periphery of the terminal hole 70 a of the lid copper plate 70 is in contact with the periphery of the housing 11 b of the upper case 11.
The side surface of the lid copper plate 70 constitutes a pressure contact portion 70c that is curved inward and is elastically deformable in a plan view. The innermost part of the pressure contact part 70c is configured to be located inside the first bent part 41b and the second bent part 42b. Accordingly, when the first bent portion 41b and the second bent portion 42b are fitted into the contact pressure portion 70c, the lid copper plate 70, the first copper plate 41, and the second copper plate 42 are in urging contact. Since the lid copper plate 70 is fixed to the upper case 11, if the upper case 11 is actually fitted to the lower case 12, the heat dissipation structure according to the present embodiment is obtained.
An elastic contact piece 71 is provided inside the upper surface of the lid copper plate 70. The elastic contact piece 71 is configured such that a copper piece is bent in the vertical direction and is elastically deformable. The elastic contact piece 71 is configured to come into contact with the circuit component 60 when the lid copper plate 70 is attached to the hierarchical structure, and the contact is maintained by the vertical elastic force generated when the contact is made. FIG. 10 shows a perspective view when a lid copper plate is attached to the hierarchical structure according to the present embodiment.

Note that the heat dissipation box in the present embodiment includes the case portion 10, the cooling fins 20, the lid copper plate 70, the first wiring board 31, the first copper board 41, the second wiring board 32, and the second copper board 42. This is a combination of

Next, the heat radiation effect of the electrical junction box 1 according to the present embodiment will be described.
The heat generated in the circuit component 60 is transmitted to the first wiring board 31 located below. The heat of the first wiring board 31 is transmitted to the first terminal 31e and the first copper plate 41. Further, the heat of the second wiring board 32 and the third wiring board 33 is transmitted to the second copper plate 42. The heat transferred to the first copper plate 41 and the second copper plate 42 is transferred to the lid copper plate 70 via the first bent portion 41b and the second bent portion 42b. Furthermore, the heat inside the case part 10 is also transmitted from the first bent part 41 b and the second bent part 42 b to the lid copper plate 70. The heat transferred to the lid copper plate 70 is transferred to the cooling fin 20 and released to the outside.
On the other hand, the heat generated in the circuit component 60 is transmitted to the cooling fin 20 through the elastic contact piece 71 and the lid copper plate 70 that are in contact with the upper surface of the circuit component 60 and is released to the outside.
Furthermore, the heat generated in the plurality of first terminals 31e is transmitted to the housing 11b. The heat transmitted to the housing 11 b is transmitted to the lid copper plate 70 that is in contact with the inner surface of the upper case 11 and is radiated from the cooling fins 20.

Since the heat dissipation structure, the heat dissipation method, and the heat dissipation box according to the present embodiment are configured as described above, the following effects can be achieved.
Since it is possible to dissipate heat with a simple configuration of providing the first copper plate 41 and the second copper plate 42 on the back surface of the first wiring board 31, the second wiring board 32, and the third wiring board 33, there is no need to provide a heat pipe. Therefore, no hydraulic fluid is required and costs can be reduced. Further, heat accumulated in the first substrate 31a, the second substrate 32a, and the third substrate 33a can also be released. Furthermore, since it is easy to ensure a contact area for heat dissipation, it is possible to obtain a high heat dissipation effect while reducing the size as a whole, and it is possible to deal with complicated circuits having many circuit components.
The first bent portion 41b and the second bent portion 42b surround the circuit component 60 that generates a particularly large amount of heat, and thus a high heat dissipation effect can be obtained. In addition, since the first bent portion 41b and the second bent portion 42b are alternately positioned in a line, the first bent portion 41b and the second bent portion 42b do not overlap with each other, so that the size is reduced. be able to.
By making the back surfaces of the wiring surfaces of the second wiring board 32 and the third wiring board 33 face each other, the single second copper plate 42 can correspond to both the second wiring board 32 and the third wiring board 33. Therefore, the number of members can be reduced and the manufacturing cost can be reduced.
Furthermore, since the heat generated in the first terminal 31e is radiated through the housing 11b, the upper case 11, and the lid copper plate 70, the heat radiation effect can be enhanced. At this time, since the upper case 11 is made of resin, only heat can be transmitted while being electrically insulated.

It should be noted that the present invention is not limited to the above-described embodiments, and it is obvious that each embodiment can be appropriately changed within the scope of the technical idea of the present invention. The number, position, shape and the like suitable for carrying out the invention can be obtained.
The hierarchical structure can be applied to any number of layers.
The first wiring board 31, the second wiring board 32, and the third wiring board 33 may be printed wiring boards.
Although the first copper plate 41 and the second copper plate 42 are provided in contact with the back surface of the wiring surface of the first wiring board 31, the second wiring board 32, and the third wiring board 33, they may be provided on the wiring surface. Moreover, you may provide in both surfaces.
The configuration in which both the first copper plate 41 and the second copper plate 42 are in contact with the cooling fin 20 via the lid copper plate 70 has been described, but one of the first copper plate 41 and the second copper plate 42 is the lid copper plate 70. The other copper plate may be in contact with the cooling fin 20 via the copper plate in contact with the cooling fin 20.
Although the case where the first bent portion 41b and the second bent portion 42b are alternately arranged is described, the present invention is also applicable to the case where the first bent portion 41b and the second bent portion 42b are arranged irregularly, such as every second or every third. .
Although the contact between the first copper plate 41, the second copper plate 42 and the lid copper plate 70 has been described by biasing, screw holes are provided on the side surfaces of the first copper plate 41, the second copper plate 42 and the lid copper plate 70, A configuration in which contact is made by screwing may be used, and a configuration in which the contact is made through another member is also applicable.
In the above embodiment, the lid copper plate 70 is provided with the contact pressure portion 70c, but the first bent portion 41b and the second bent portion 42b are provided with the contact pressure portion. May be.
In the embodiment described above, the circuit component 60 is surrounded by the first bent portion 41b and the second bent portion 42b. However, a configuration in which another member having a particularly large amount of heat generation may be surrounded. .
The bus bar described in the present embodiment refers to a bus bar in the JIS industrial terminology dictionary.

It is a perspective view of the electrical junction box concerning this embodiment. It is sectional drawing of the electrical-connection box concerning this Embodiment. It is an enlarged view of A in FIG. It is a perspective view of the 1st wiring board concerning this Embodiment. It is a perspective view of the 2nd wiring board concerning this Embodiment. It is a perspective view of the 1st copper plate concerning this embodiment. It is a perspective view of the 2nd copper plate concerning this embodiment. It is a perspective view of the hierarchical structure which concerns on this Embodiment. It is a perspective view of a lid copper plate and a cooling fin concerning this embodiment. It is a perspective view at the time of attaching a cover copper plate to the hierarchical structure concerning this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrical junction box 10 Case part 11 Upper case 11a Opening part 11b Housing 12 Lower case 20 Cooling fin (heat radiating member)
31 First wiring board (wiring board)
31a First substrate 31b First bus bar 31c First elongated hole 31d Second elongated hole 31e First terminal (terminal)
32 Second wiring board (wiring board)
32a Second substrate 32b Second bus bar 32d Second elongated hole 32e Second terminal (terminal)
33 Third wiring board (wiring board)
33a Third substrate 33b Third bus bar 33e Third terminal (terminal)
41 1st copper plate (first heat conducting member)
41a 1st insertion part 41b 1st bending part (bending part)
42 Second copper plate (first heat conducting member)
42a 2nd insertion part 42b 2nd bending part (bending part)
50 Insulation sheet (insulation member)
60 Circuit parts (circuit parts)
70 Lid copper plate (second heat conduction member)
70a Terminal hole 70b Screw hole 70c Pressure contact part 71 Elastic contact piece

Claims (9)

A heat dissipation structure that releases heat of an electrical junction box provided with a wiring board to the outside by a heat dissipation member partially exposed to the outside of the electrical junction box,
The first heat conducting member is in contact with the wiring board,
The heat dissipation structure, wherein the heat dissipation member is in contact with the first heat conducting member. The wiring board is plural,
A plurality of the wiring boards are laminated,
The heat dissipation structure according to claim 1, wherein the first heat conducting member is in contact with a plurality of the wiring boards. The heat dissipation structure according to claim 1, wherein an insulating member is provided between a wiring surface of the wiring board and the first heat conducting member. 4. The heat dissipation structure according to claim 1, wherein one of the first heat conducting members is in contact with the plurality of wiring boards. 5. A second heat conducting member is in contact with the heat radiating member,
A part of the first heat conducting member is bent to form a bent portion;
The heat dissipation structure according to claim 1, wherein the bent portion is in contact with the second heat conducting member. The heat dissipation structure according to claim 5, wherein the bent portion is located at a peripheral edge of the wiring board. The first heat conducting member is plural,
In a state where the wiring board and the plurality of first heat conducting members are stacked, the plurality of bent portions provided on the plurality of first heat conducting members surround an outer edge of the wiring board. The heat dissipation structure according to claim 5. The wiring board is provided with circuit components,
The heat dissipation structure according to claim 1, wherein the circuit component is in contact with the heat dissipation member. A heat dissipation box with a wiring board inside,
An upper case and a lower case that fits into the upper case;
A heat dissipation member is provided in the upper case,
A heat dissipation box, wherein the lower case is provided with a first heat conducting member in contact with the wiring board.

Images