JP2006050817A - Electrical junction box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a short circuit between terminals drawn out from a connector by draining water droplets outside the apparatus.
An electrical connection box 60 is mainly composed of a casing 20 that accommodates a circuit board 11 therein, a fuse box 51 for protecting electrical components, an upper connector housing 52, and a lower connector housing 31. Arranged vertically. Among these, a plurality of terminals 33 project from the upper surface 37 of the lower connector housing 31, and each projecting terminal 33 is connected to the circuit board 11. A drainage groove 41 that opens to the outside of the casing 20 is formed on the upper surface 37 of the lower connector housing 31. Therefore, even if water droplets gather on the upper surface 37 along the wall surface of the casing 20, the water droplets are drained to the outside through the drainage grooves 41, so that moisture does not remain in the same portion. Thereby, a short circuit between the terminals 33 is prevented in advance.
[Selection] Figure 5

Description

  The present invention relates to an electrical junction box.

Conventionally, in an electrical junction box mounted on an automobile, various waterproof measures have been taken in order to protect a substrate housed in the interior or to take measures against a short circuit of a bus bar, a terminal or the like (Patent Document 1).
In this device, an attachment portion 3c for connecting an external connector is integrally provided on the upper surface of a frame 3 for accommodating the circuit board 5. The attachment portion 3c is provided with a terminal accommodation hole 3d penetrating vertically, and a connection terminal (bus bar) for connecting the terminal provided in the external connector and the circuit board 5 is accommodated therein. For this reason, there is a possibility that the moisture that has entered through the terminal accommodating hole 3d is transmitted through the bus bar and soaks the circuit board 5 inside the electrical junction box.
Therefore, another part is liquid-tightly fitted on the outer periphery of the bus bar on the path from the mounting portion 3c to the circuit board 5, thereby protecting the circuit board 5 by changing the path of moisture passing through the bus bar. It was.
JP 2003-348732 A

Since there is water intrusion due to condensation or the like in the electrical junction box, if the moisture inside the junction box is left unattended, water accumulates on the bottom surface of the electrical junction box. In this case, if the connector is arranged on the bottom surface portion of the electrical junction box, there is a possibility that the terminal connecting the circuit board and the connector may be short-circuited, and there is room for improvement.
The present invention has been made based on the above situation, and an object of the present invention is to drain internal water droplets outside the apparatus and prevent a short circuit between terminals drawn out from a connector.

  As a means for achieving the above object, the invention of claim 1 is characterized in that an opening that opens downward is formed in a casing that accommodates the circuit board, and a connector is disposed so as to close the opening, An electrical connection box formed by connecting a plurality of terminals projecting from the upper surface of the connector housing of the connector to the circuit board, wherein the upper surface of the connector housing is provided with a drainage groove that opens to the outside of the casing. It has a characteristic where it exists.

  The invention of claim 2 is characterized in that, in the invention of claim 1, the drain grooves are formed in a direction orthogonal to the arrangement direction of the terminals.

  The invention of claim 3 is the one according to claim 1 or claim 2, wherein the connector housing of the connector is provided with a plurality of hood portions for accommodating the mating connector, and the drain groove is It is characterized by being formed between the hood portions.

  According to a fourth aspect of the present invention, there is provided the apparatus according to any one of the first to third aspects, wherein the circuit board is arranged vertically in the casing.

<Invention of Claim 1>
According to the first aspect of the present invention, since the water droplets on the upper surface of the connector housing are discharged to the outside through the drainage grooves, the water droplets do not accumulate in the same portion. Therefore, a short circuit between terminals in the same portion is prevented in advance.

<Invention of Claim 2>
According to the invention of claim 2, since the groove path is short, drainage is performed quickly.

<Invention of Claim 3>
According to invention of Claim 3, it becomes possible to drain a water drop from the clearance gap between adjacent connectors. With such a configuration, water droplets do not enter the fitting portion of the connector.

<Invention of Claim 4>
According to the fourth aspect of the present invention, water droplets are more likely to collect at the lower part of the electrical junction box as compared with the case where the circuit board is placed horizontally, so that the drainage is improved.

An embodiment of the present invention will be described with reference to FIGS.
1 shown in FIG. 1 is an electrical junction box used in an automobile, which is interposed between a power source such as a battery and an electrical load, and distributes and supplies power supplied from the power source to each electrical component. The control for switching the power supply is performed. The electrical junction box 60 accommodates the circuit structure 10 in a casing 20 having a heat dissipation function, and is arranged vertically in the engine room.

  As shown in FIG. 2, the circuit structure 10 includes a circuit board 11, an electronic component 12 mounted on a circuit pattern (not shown) formed on the upper surface of the circuit board 11, and a lower surface of the circuit board 11. It is comprised from the bus-bar (electric power conduction path) 13 which consists of the metal plate material which is distribute | arranged and connected to a power supply (not shown). The circuit board 11 and the bus bar 13 are integrated via an insulating adhesive (not shown). Moreover, an adhesive agent and an adhesive sheet etc. shall be contained in an adhesive material here.

  The casing 20 includes a synthetic resin frame 21, a metal (for example, aluminum alloy) heat dissipation plate 22 having a high thermal conductivity, and a cover 55. The frame body 21 has a shape along the outer shape of the circuit board 11, and surrounds the circuit board 11 continuously without any breaks over the entire circumference. The heat radiating plate 22 has substantially the same shape as the outer shape of the frame body 21, and is assembled to the frame body 21 from the lower surface side. Further, a gel-like potting agent is introduced into the frame body 21 up to the height of the alternate long and short dash line L shown in FIG. 7, thereby protecting the circuit board 11 (waterproofing) by covering the surface of the circuit board 11. Yes.

  As shown in FIG. 7, a fuse box 51 is assembled to the upper edge of the circuit board 11, and an upper connector housing 52 is assembled to the fuse box 51. Although not shown in detail, a connector connected to an electrical load is connected to the upper connector housing 52.

The cover 55 is formed in a size capable of closing the opening surface (the upper surface in FIG. 2) of the frame body 21, and is assembled to the frame body 21 from above in the figure.
One edge of the cover 55 bulges in the opposite direction of the circuit board 11 (upward in FIG. 2) over its entire width. The bulging portion 56 is opened to the front side (lower side in the attached state) in FIG. 2, and a lower connector 30 described below is disposed so as to close the opening 56A. The opening 56A corresponds to the opening of the present invention.

  The lower connector housing 31 constituting the lower connector 30 has a horizontally long box shape and is partitioned into three hood portions 32 by a pair of partition walls 31A. Each hood portion 32 has a mating connector 57 (see FIG. 4). ) Can be assembled. Mounting edges 31B are formed on the left and right side surfaces of the lower connector housing 31 so as to project laterally. On the other hand, a seat portion 21 </ b> C having a screw hole is provided at a portion facing the attachment edge 31 </ b> B in the frame body 21. Further, a fixing portion 35 which is cylindrical from the side wall (the right side wall in FIG. 7) 36 of the lower connector housing 31 and has a screw hole formed at the tip thereof projects toward the circuit board 11 side. Yes.

  Therefore, the mounting edge 31B is screwed to the seat portion 21C (see FIG. 3), and the circuit board 11 is screwed to the fixing portion 35 (see FIG. 7), so that the lower connector housing 31 is connected to the circuit board. 11 and the frame 21 can be fixed. In addition, a recess 22A is formed in the lower part of the heat radiating plate 22, and this is for releasing a screw for fixing the lower connector housing.

  As shown in FIG. 7, two rows of mounting projections 38 and 39 projecting upward in the figure are formed on the upper surface 37 of each hood portion 32. The mounting protrusions 38 and 39 are formed along the width direction of each hood portion 32 (see FIG. 5), and a plurality of terminals 33 are press-fitted therethrough so as to penetrate the upper surface 37.

  The tip of the terminal 33 is bent about 90 degrees toward the circuit board 11 in the casing 20. The bent end of the terminal 33 is inserted into the insertion hole 14 provided in the circuit board 11 and then connected to the circuit board 11 by soldering.

  Further, since the mating connector 57 that is the mating side is assembled to the lower connector housing 31 from the lower side in FIG. Therefore, the lower connector housing 31 is supported by the cover 55 so as to resist the force in the insertion / removal direction. More specifically, a convex portion 56B that protrudes inward is provided at the lower end portion of the cover 55, and a protruding piece is formed at the upper end portion of the mounting projection 39 that is located closer to the cover 55 of the mounting projections 38 and 39. And a recess 39 </ b> A is formed between the connector upper surface 37 and the connector upper surface 37. The convex portion 56B and the concave portion 39A are adapted to be engaged with each other so as to resist a force in the pulling direction (downward direction in FIG. 7). Further, the cover 55 is disposed so that the lower end portion thereof is along the upper surface 37 of the lower connector housing 31. Thus, support in the insertion direction (upward direction in FIG. 7) is intended.

  Incidentally, two drain grooves 41 are formed on the outer wall surface of the lower connector housing 31 so as to extend over both the upper surface 37 and the exposed surface 40. As shown in FIG. 5, each drainage groove 41 is straight outward (the vertical direction in FIG. 5, where the terminals 33 are arranged), starting from the base end portion (the portion facing the circuit board 11) of the upper surface 37 of the lower connector housing 31. Direction). Then, after reaching the exposed surface 40, the drainage groove 41 is straight toward the fitting surface of the lower connector housing 31 (the fitting surface with the mating connector 57, which is the lower surface when attached) 31C. In addition, the terminal end reaches the fitting surface 31C.

  Each drainage groove 41 is located between the hood portions 32 in the width direction (see FIG. 1). With such an arrangement, the moisture in the electrical junction box 60 is drained out of the casing 20 through the gap between adjacent mating connectors 57 (D dimension portion shown in FIG. 4). Further, the groove width and depth of the drainage groove 41 are set so that water droplets in the electrical junction box 60 are smoothly drained through the drainage groove 41.

  Further, a gap 21B is formed between the opposing surfaces of the lower connector housing 31 and the frame body 21 as shown in FIG.

Next, the operation and effect of this embodiment will be described.
Although water droplets may enter the electrical junction box 60 due to condensation or the like, the water droplets that have entered in this case pass through the surface of the potting agent to the lower part of the electrical junction box 60 (FIG. 7). Or a route (route indicated by an arrow b in FIG. 7) traveling along the inner surface of the cover 55. Among these, the water droplets transmitted on the surface of the circuit board 11 eventually reach the mating portion (side wall 36) of the lower connector housing 31 with the frame body 21. Then, the water droplets are drained below the electrical junction box 60 through the gap 21 </ b> B formed between the opposing surfaces of the side wall 36 and the frame body 21.

  On the other hand, when it travels along the inner surface of the cover 55, it eventually reaches the upper surface 37 of the lower connector housing 31. Thereafter, the water droplet spreads along the upper surface 37, but since the drainage groove 41 is formed there, the waterdrop flows along the groove 41 when reaching the drainage groove 41, and eventually the electrical connection box 60 It is drained downward.

  As described above, according to the present embodiment, the water droplets inside the electrical junction box 60 are drained outside the apparatus regardless of the route that travels along the circuit board 11 and the route that travels along the inner surface of the cover 55. Therefore, water droplets do not stay inside the electrical connection box 60 (in particular, the upper surface 37 of the lower connector housing 31). Therefore, a short circuit between the terminals 33 is prevented.

  Further, the drainage groove 41 extends straight in a direction orthogonal to the arrangement direction of the terminals 33. With such a groove path, drainage is performed quickly because the entire length of the groove is short. In addition, each drainage groove 41 is located between the hood portions 32 in the width direction. With such an arrangement, water droplets can be drained from the gap between the mating connectors 57 (D dimension portion shown in FIG. 4), so that the drained water droplets are in the fitting portions of both connectors 30 and 57. It becomes difficult to invade.

  Further, each terminal 33 passes through attachment protrusions 38 and 39 formed on the upper surface 37, and the exposed position of each terminal 33 is higher than the upper surface 37 by the height of the attachment protrusions 38 and 39. With such a configuration, even if a large amount of water drops enter the upper surface 37 at a time, if the water drops are within the height range of the mounting projections 38 and 39, a short circuit of the terminal 33 is avoided. I can do it.

<Other embodiments>
The present invention is not limited to the embodiments 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) In the present embodiment, the electric connection box 60 is vertically arranged in the engine room. However, there is no particular restriction on the installation direction, and the present invention can be applied to, for example, a horizontally used one. .

The perspective view of the electrical junction box concerning one embodiment of the present invention. Disassembled perspective view of electrical junction box The perspective view which shows the state which removed the cover Front view with cover removed Perspective view showing drainage ditch Bottom view of electrical junction box Cross section of electrical junction box

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 ... Casing 31 ... Lower connector housing 33 ... Terminal 37 ... Upper surface 41 ... Drainage groove 55 ... Cover 60 ... Electric junction box

Claims (4)

An opening that opens downward is formed in the casing that houses the circuit board, and a connector is disposed so as to close the opening,
An electrical connection box formed by connecting a plurality of terminals protruding from the connector housing upper surface of the connector to the circuit board,
An electrical junction box, wherein a drainage groove that opens to the outside of the casing is provided on an upper surface of the connector housing. The electrical junction box according to claim 1, wherein the drainage groove is formed in a direction orthogonal to the arrangement direction of the terminals. The connector housing of the connector is provided with a plurality of hood portions that accommodate the mating connector,
The electrical junction box according to claim 1, wherein the drainage groove is formed between the hood portions. The electrical connection box according to any one of claims 1 to 3, wherein the circuit board is arranged vertically in the casing.

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