JP6450241B2 - Electrical junction box - Google Patents

Description

  The present invention relates to an electrical junction box having a heat dissipation structure.

2. Description of the Related Art Conventionally, a heat dissipation structure for an electrical junction box is known in which an opening is formed in a case or the like to radiate heat inside the case (see Reference 1).
However, in an electrical junction box in which a control board such as an electronic unit is accommodated in the case, if an opening is formed in the case, foreign matter (dust, dust, tools, etc.) that has entered from the opening will cause the control board to There are problems such as destruction of mounted electronic components and short circuit of the circuit, leading to failure.

On the other hand, as a heat dissipation structure for game machines such as pachinko machines, there has been proposed a technique for preventing the entry of foreign objects such as tools by making it difficult to visually recognize an opening for heat dissipation from the outside (see Patent Document 2).
However, in an electrical junction box placed in a small space in the engine room of a car or at the foot of a driver's seat, surrounding equipment may be damaged by the edge of the side wall standing from the base, The above-described heat dissipation structure cannot be employed.

JP 2007-282402 A JP 2010-088950 A

  An object of the present invention is to solve the above-described problems caused by the prior art and to provide an electrical junction box having a heat dissipation structure that prevents foreign matter from entering the case.

An electrical junction box according to the present invention is a junction box main body having an internal circuit and a first housing that accommodates the internal circuit, and at least a concave portion formed on one side surface and opposed to the periphery of the concave portion. and two convex portions, and the connection box body having a unit mounting portion provided on the concave-shaped portion, the control board unit having a second housing for housing the control board is connected and this to the internal circuit A control board unit mounted on the unit mounting portion, and a gap portion is formed between the peripheral wall portion of the second casing and the convex portion facing the second casing, The housing has a groove-like recess communicating with the gap on the contact surface side with the unit mounting portion, and an opening formed in the recess .

According to the electrical junction box of the present invention, a gap portion is formed between the convex portion formed around the unit mounting portion of the first housing of the junction box body and the control board unit mounted on the unit mounting portion. And a recess formed on the contact surface side of the control board unit with the unit mounting portion of the second housing communicates with the gap, and an opening is formed in the recess.
For this reason, the heat in the 2nd housing | casing of a control board unit can be discharged outside from an opening part through a recessed part and a gap | interval part, and the heat radiation in a control board unit can be aimed at. In addition, since the control board unit and the junction box body are separated from each other by the recess formed in the second housing (because there is a space in the recess), heat transfer between the control board unit and the junction box body is suppressed. (Heat insulation). Further, since the opening of the second casing is formed on the contact surface side with the unit mounting portion, the opening cannot be visually recognized from the outside, and the inside of the control board unit (inside the second casing). It is possible to prevent foreign matter from entering.

  In the electrical junction box, the second housing of the control board unit includes a lower case to which the control board is attached and an upper case attached to the lower case so as to cover the control board, and the recess and The opening may be formed in the lower case, and the control board may be attached to the upper side of the opening in a state of forming a predetermined gap with respect to the lower case.

In the electrical junction box, the one peripheral wall of the second housing of the control board unit facing the one convex portion of the junction box body is directed from the bottom side of the unit mounting portion toward the opening side. inclined to the gap is narrowed, a peripheral wall surface facing the second housing of the other of the convex portion of the connection box body, toward the opening side from the bottom side of the unit mounting portion, the gap portion The bottom surface of the unit mounting portion that faces the concave portion is inclined such that the distance between the concave portion and the bottom surface decreases from one convex portion to the other convex portion of the connection box body. It may be formed so as to be inclined.

  In the electrical junction box, a plurality of the openings may be formed below the control board.

  According to the present invention, it is possible to reduce the possibility of malfunction due to the entry of a foreign substance as much as possible without sacrificing heat dissipation and to be suitable for mounting on a vehicle.

It is a perspective view showing the appearance of the electric junction box concerning a 1st embodiment of the present invention. It is a perspective view which shows the state which isolate | separated the control board unit and the junction box main body of the same electrical junction box. It is a disassembled perspective view of the control board unit of the same electrical junction box. It is A-A 'sectional drawing of FIG. It is a perspective view which shows the state which isolate | separated the control board unit and the connection box main body of the electrical connection box with a control board which concern on the 2nd Embodiment of this invention. It is sectional drawing which shows the state at the time of installation of the same electrical junction box. It is sectional drawing which shows the electrical-connection box which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows the electrical junction box which concerns on the 4th Embodiment of this invention.

  Hereinafter, an electrical junction box according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing an appearance of an electrical junction box according to the first embodiment of the present invention. 2 is a perspective view showing a state in which the control board unit of the electrical junction box and the junction box main body are separated, FIG. 3 is an exploded perspective view of the control board unit of the electrical junction box, and FIG. 4 is AA ′ of FIG. It is sectional drawing.

  As shown in FIGS. 1-4, the electrical junction box 1 which concerns on 1st Embodiment is used as an electrical junction box mounted, for example in vehicles, such as a motor vehicle. The electrical junction box 1 includes a control board unit 2 that accommodates a control board in a second casing 10, an internal circuit in a first casing 20, and a junction box body 3 to which the control board unit 2 is attached. It is configured with. The first and second housings 20 and 10 of the control board unit 2 and the junction box body 3 are made of, for example, a resin molded member.

  The control board unit 2 is configured to accommodate a control board 4 on which an electronic component 15 is mounted inside a rectangular second housing 10. The junction box body 3 is configured by accommodating an internal circuit (not shown) including a bus bar (not shown) connected to the control board 4 of the control board unit 2 in the rectangular first housing 20.

  The junction box body 1 is formed by accommodating an internal circuit inside a rectangular first housing 20. In addition, a concave portion is formed on one side surface of the first housing 20, and at least two convex portions 21 are disposed opposite to each other around the concave portion, and the concave portion between the convex portions 21 is provided. Further, a unit mounting portion 40 to which the control board unit 2 is attached is provided. The mounting surface 41 of the unit mounting part 40 is formed in a flat shape.

  The first housing 20 of the connection box body 3 is formed with a connector portion 22 in which an external connector (not shown) is fitted and connected to the top of the convex portion 21, for example. The first housing 20 is formed with a plurality of positioning bosses 30 extending upward at a predetermined length on the unit mounting portion 40.

  On the other hand, for example, as shown in FIG. 3, the control board unit 2 is attached to the upper case 11 and the lower case 12 constituting the second housing 10 and the lower case 12 and accommodated in the second housing 10. And a control board 4. The upper case 11 and the lower case 12 are each a known locking mechanism (not shown) including engaging protrusions formed at positions corresponding to each other on the opposing surface and side surfaces, engaging grooves into which the protrusions fit, and the like. ) Are detachably engaged with each other to constitute the second housing 10. Note that the control board unit 2 and the junction box body 3 may also be attached by a lock mechanism (not shown).

  For example, as shown in FIG. 4, the control board unit 2 and the connection box main body 3 include a pair of second housings 10 that face the peripheral wall surfaces 21 a of the pair of convex portions 21 on the unit mounting portion 40 at the time of mounting. They are attached to each other such that gaps 19 are formed between the peripheral wall surface 10a.

  For example, as shown in FIG. 4, the upper case 11 is formed in a U-shaped cross section that opens toward the lower case 12, and the lower case 12 covers the control board 4 attached to the lower case 12 as a whole. Attached to. In the upper case 11, for example, a screw 31 is inserted into a position corresponding to the screw hole 30 a of the boss 30 extending from the unit mounting portion 40 of the junction box body 3, and the control board unit 2 is attached and fixed to the unit mounting portion 40. A screw hole 13 is formed. Further, on the upper surface side of the upper case 11, a connector hole 14 for allowing the connector portion 29 mounted on the control board 4 to pass outside is formed at a predetermined location.

  As shown in FIG. 3, the control board 4 attached to the lower case 12 has an electronic component 15 such as an electronic control unit (ECU) connected to an internal circuit and a connector connected to an external connector of an external circuit (not shown). A boss insertion hole 16 through which the boss 30 is inserted is formed at a predetermined location. Also, mounting holes 17 for the lower case 12 are formed in the vicinity of the four corners of the control board 4 and other predetermined locations.

  The lower case 12 includes a planar substrate arrangement surface 12a, and substrate support pins 18 are formed at positions corresponding to the mounting holes 17 formed in the control substrate 4 of the substrate arrangement surface 12a. A boss insertion hole 33 through which the boss 30 is inserted is formed at a predetermined location of the lower case 12. In addition, the control board 4 attaches the screw 17a to the screw hole 18a of the board support pin 18 fitted in the mounting hole 17 so that a predetermined gap is formed between the lower case 12 and the board placement surface 12a. Attached to.

  The lower case 12 is formed with a groove-like recess 6 extending between the pair of gaps 19 described above on the surface side that contacts the mounting surface 41 of the unit mounting portion 40 during mounting. In the lower case 12, an opening 5 is formed on the upper side (the bottom surface of the recess) of the recess 6. The recess 6 forms a heat dissipation space 6a that connects the gap portion 19, and the opening 5 communicates the internal space 32 of the second housing 10 and the heat dissipation space 6a. In this example, a plurality of openings 5 are formed along the recess 6 below the control board 4.

  In the electrical junction box 1 configured as described above, the control board unit 2 is arranged on the unit mounting portion 40 by the boss 30 of the junction box main body 3 fitted into the screw hole 13 through the boss insertion holes 33 and 16. Positioned so as to form each gap portion 19 and attached to the junction box body 3.

  Each gap portion 19 is spatially connected to the internal space 32 of the control board unit 2 and the external space on the unit mounting portion 40 via the heat dissipation space 6 a, the opening 5, and a predetermined gap below the control board 4. Yes. Therefore, the heat in the internal space 32 generated from the electronic component 15 or the like of the control board 4 is effectively exhausted to the external space through the predetermined gap, the opening 5, the heat radiation space 6a, and the gap 19.

  And since the opening part 5 is arrange | positioned in the location which cannot be visually recognized from the outer side of the electrical junction box 1 compared with the conventional thing, Since the convex-shaped part 21 which comprises the unit mounting part 40 is formed in convex shape. It is difficult for foreign matter from the outside to enter the internal space 32 of the control board unit 2 through the opening 5. In this way, the electrical junction box 1 according to the first embodiment can reduce the possibility of malfunctions due to foreign object intrusion as much as possible without sacrificing heat dissipation.

  FIG. 5 is a perspective view showing a state in which the control board unit and the junction box body of the electrical junction box according to the second embodiment of the present invention are separated. Moreover, FIG. 6 is sectional drawing which shows the state at the time of installation of an electrical junction box. The electrical junction box 1A according to the second embodiment is the same as the electrical junction box 1 according to the first embodiment in that the control board unit 2 and the junction box body 3 are provided, but has a structure that improves waterproofness. The point is different.

  As shown in FIGS. 5 and 6, in the electrical junction box 1 </ b> A according to the second embodiment, first, the upper peripheral wall surface 10 a in the installation state (FIG. 6) of the upper case 11 of the control board unit 2 is mounted on the unit. The gap portion 19 is inclined so as to gradually narrow from the mounting surface 41 side of the portion 40 toward the opening side.

  Further, the peripheral wall surface 21a of the lower convex portion 21 in the installation state (FIG. 6) of the first casing 20 of the junction box body 3 is spaced from the mounting surface 41 side of the unit mounting portion 40 toward the opening side. It inclines so that the space of the part 19 may spread.

  Further, of the mounting surface 41 at the bottom of the unit mounting portion 40 of the junction box body 3, the portion facing the heat radiation space 6 a is a convex portion on one side of the first housing 20 (upper side in the installed state (FIG. 6)). The heat radiation space 6a narrows from the 21 side toward the other convex portion 21 side (the lower side in the installed state (FIG. 6)), that is, from the oblique circumferential wall surface 10a side to the oblique circumferential wall surface 21a side. Inclined.

  Thereby, as shown in FIG. 6, when the electrical junction box 1A is arranged with the oblique peripheral wall surface 10a facing upward, the opening of the gap portion 19 on the peripheral wall surface 10a side becomes narrow, and moisture enters from here. A difficult structure can be obtained. Further, even if moisture enters the gap portion 19 from this opening, the entered moisture flows toward the heat radiation space 6a by the inclined peripheral wall surface 10a.

  Then, the moisture flows through the heat radiating space 6a to the other (lower) gap 19 side by the oblique mounting surface 41. When moisture passes through the heat radiating space 6a, the moisture falls in the space closer to the mounting surface 41 or flows along the mounting surface 41 due to the effect of the oblique peripheral wall surface 10a. It is difficult to enter the internal space 32 of the control board unit 2.

  Further, on the other gap portion 19 side, it flows to the opening side of the gap portion 19 by the inclined peripheral wall surface 21a, and is finally discharged to the outside from the opening. Therefore, moisture does not stay between the control board unit 2 and the junction box body 3 and can be reliably drained to the outside, so that problems such as a short circuit due to moisture can be prevented. As described above, the electrical junction box 1A according to the second embodiment can provide the same operational effects as the electrical junction box 1 according to the first embodiment, and can have high waterproof properties.

  FIG. 7 is a cross-sectional view showing an electrical junction box according to the third embodiment of the present invention. As shown in FIG. 7, the electrical junction box 1 </ b> B according to the third embodiment is different from the electrical junction box 1 according to the first embodiment in the formation mode of the opening 5. In other words, the lower case 12 of the control board unit 2 has a plurality of openings 5 provided on the board placement surface 12a below the control board 4 and the second part detached from the lower side of the control board 4 as described above. Openings 5a provided in the substrate placement surface 12a at positions close to the peripheral wall surface 10a of the housing 10 are formed.

  As a result, as indicated by an arrow in the figure, the air that has entered from the opening of the gap portion 19 flows more easily through the opening portion 5a as well as through the inner space 32 of the control board unit 2 as well as the inner portion. A structure in which air in the space 32 can easily flow from the gap portion 19 not only through the opening portion 5 but also through the opening portion 5a can be provided. For this reason, while having the same effect as the electrical junction box 1 which concerns on 1st Embodiment, it becomes possible to improve heat dissipation more.

  FIG. 8 is a cross-sectional view showing an electrical junction box according to the fourth embodiment of the present invention. As shown in FIG. 8, the electrical junction box 1 </ b> C according to the fourth embodiment is different from the electrical junction box 1 according to the first embodiment in the mounting mode of the electronic component 15 on the control board 4. That is, an electronic component 15 that generates a large amount of heat is mounted on the control board 4 in the control board unit 2 on the side facing the opening 5. Thereby, the heat generated in the electronic component 15 is immediately radiated to the heat radiating space 6a through the opening 5, and the same effect as the above effect can be obtained and the heat dissipation can be enhanced. . Note that the configurations of the above-described embodiments can be combined.

1, 1A, 1B, 1C Electrical junction box 2 Control board unit 3 Junction box body 4 Control board 5, 5a Opening 6 Recess 6a Heat radiation space 10 Second housing 10a, 21a Peripheral wall surface 11 Upper case 12 Lower case 12a Board layout Surface 13, 18, 30a Screw hole 14 Connector hole 15 Electronic component 16, 33 Boss insertion hole 17 Mounting hole 17a, 31 Screw 19 Gap portion 20 First housing 21 Convex portion 22, 29 Connector portion 30 Boss 40 Unit mounting Part 41 Mounting surface

Claims (4)

A junction box main body having an internal circuit and a first housing for accommodating this, a concave portion formed in one side surface, and at least two convex portions disposed opposite the periphery of the concave portion, the concave A junction box body having a unit mounting portion provided in the shape portion;
A control board unit having a control board connected to the internal circuit and a second housing for accommodating the control board, the control board unit mounted on the unit mounting part;
A gap portion is formed between the peripheral wall portion of the second housing and the convex portion facing it,
The electrical connection box, wherein the second housing has a groove-like recess communicating with the gap portion on the contact surface side with the unit mounting portion, and an opening formed in the recess . The second housing of the control board unit includes a lower case to which the control board is attached and an upper case attached to the lower case so as to cover the control board,
The recess and the opening are formed in the lower case,
The electrical connection box according to claim 1, wherein the control board is attached to an upper side of the opening in a state where a predetermined gap is formed with respect to the lower case. The one peripheral wall of the second housing of the control board unit facing the one convex portion of the connection box body is configured such that the gap portion narrows from the bottom side of the unit mounting portion toward the opening side. Tilt,
Circumferential wall facing the second housing of the other of the convex portion of the connection box body, toward the opening side from the bottom side of the unit mounting portion, inclined to the gap portion is widened,
The bottom surface facing the concave portion at the bottom of the unit mounting portion is formed so as to be inclined so that the distance between the concave portion and the bottom surface decreases from one convex portion to the other convex portion of the junction box body. The electrical junction box according to claim 1, wherein the electrical junction box is provided. The electrical connection box according to claim 1, wherein a plurality of the openings are formed below the control board.

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