JP5630103B2 - Electrical junction box - Google Patents

Description

  The present invention relates to an electrical junction box.

  Conventionally, what is described in Patent Document 1 is known as an electrical connection box that is mounted on a vehicle and performs energization and disconnection of in-vehicle electrical components such as a lamp and a horn. This electrical junction box is configured by housing a circuit board on which electronic components are mounted and a frame body in which water blocking walls are formed on both sides along the arrangement direction of the terminal fittings and the circuit board is mounted in the case. ing.

  Here, on the upper surface of the case, an upper connector housing into which an external connector is fitted, and a fuse mounting portion to which a fuse can be mounted are formed. Of these, in the upper connector housing, the lower portion of the cylindrical portion that opens in a cylindrical shape is recessed below the upper surface of the case, and the terminal fittings of the frame body are inserted into the insertion holes in the bottom surface. ing.

  Thus, since it is the structure by which a terminal metal fitting is inserted in the insertion hole of a bottom face, it can also be considered that water enters the case from the gap of the insertion hole. About this water, when water reaches the upper surface part (inclined surface) of the frame body from the insertion hole by making the upper surface part of the frame body partitioned on both sides by the water blocking wall into an inclined surface, both sides of the water blocking wall Therefore, the water on the inclined surface is led to the drain outlet at the end and is discharged from below the electric junction box.

JP 2009-290941 A

  However, there may be a case where the water that has entered the case through the insertion hole is not drained from the drainage path including the inclined surface and the drainage port. Specifically, the water that has entered through the insertion hole rises by a capillary phenomenon in a slight gap between the back surface of the recessed portion of the cylindrical portion and the water stop wall of the frame, and exceeds the water stop wall. It is conceivable to enter a region such as a circuit board.

  The present invention has been completed based on the above situation, and an electrical junction box that can prevent water entering the case from entering the side of the circuit board or the like beyond the water blocking wall. The purpose is to provide.

An electrical junction box according to the present invention includes a circuit board, a synthetic resin frame that holds the circuit board and the terminal fitting, a connector on the upper surface that can accommodate the circuit board and the frame body from a lower opening. And a case provided with a fitting portion having a rectangular tube shape to be fitted, wherein the fitting portion has a cylindrical depression portion recessed with respect to an upper surface of the case, and the cylinder An insertion hole through which one end side of the terminal fitting is inserted is formed in the bottom surface portion of the recessed portion, and the lock receiving portion for receiving the distal end side of the lock arm of the connector is recessed in the fitting portion. A bulging portion is formed by the lock housing portion on the outer surface of the cylindrical recess portion, and the outer surface of the cylindrical recess portion is inserted into the insertion hole in the frame body. A pair of water blocking walls facing each other, the cylindrical depression and Of opposing surfaces of Kitome waterwall, the surface of the water stop wall, the notch drainage directing water entering the drainage path between the opposing surfaces are formed, the water stop wall Is characterized in that a thin-walled portion is formed at a position facing the bulging portion, and the drainage notch is formed so as to avoid the thin-walled portion of the water blocking wall. .

In this way, even if the water rises between the mutually facing surfaces of the cylindrical depression and the water blocking wall due to capillary action, when this water reaches the drainage notch, the cylindrical depression and Since the gap between the water blocking wall and the water stop wall increases, the water does not rise, and can be guided to the drainage path through the drainage notch. Therefore, it is possible to prevent water from entering the circuit board or the like beyond the water blocking wall.
Further, it is generally easier to form the drainage notch than the drainage notch in the cylindrical depression.
Of the water blocking walls, it is considered that the strength of the water blocking wall may be insufficient if the cutout portion for drainage is formed in the thin wall portion, but according to this configuration, the cutout portion for drainage is formed avoiding the thin wall portion. Therefore, it is possible to prevent the strength of the water blocking wall from being insufficient.

In addition, it is good also as following structures .

( 1 ) The drainage path is composed of an inclined surface provided between the pair of water blocking walls and a drainage through hole that is connected to a terminal portion of the inclined surface and penetrates the frame body up and down. The water passes through the drainage through hole and is discharged from the lower end of the drainage through hole to the outside.
If it does in this way, water can be efficiently discharged outside.

( 2 ) The notch for drainage is cut out in an inclined shape in a direction along the inclined surface.
Even if the notch of the drainage notch is inclined in any direction, it is possible to guide water to the drainage through hole through the inclined surface, but according to this configuration, the drainage notch is Since it is cut out in an inclined shape in the direction along the inclined surface, water can be guided directly to the drainage through hole through the inclined surface.

  According to the present invention, it is possible to prevent water from entering the circuit board or the like beyond the water blocking wall.

1 is an exploded perspective view of an electrical junction box according to Embodiment 1. FIG. Rear view showing electrical junction box Top view showing the electrical junction box AA sectional view of FIG. BB sectional view of FIG. CC sectional view of FIG. DD sectional view of FIG. The figure explaining the state where the water which rose by capillary phenomenon is led to the drainage channel by the notch for drainage Bottom view showing the case Top view of the frame EE sectional view of FIG. FF sectional view of FIG.

<Embodiment 1>
Embodiment 1 of the present invention will be described with reference to the drawings.
The electrical junction box 10 is arranged between a power source (not shown) in the vehicle and on-vehicle electrical components (not shown) such as a lamp and a horn, and performs energization and disconnection of the on-vehicle electrical components. In the following, the vertical direction and the horizontal direction will be described with reference to FIG. 2, with the back side of the paper in FIG. The electrical connection box 10 is attached to the vehicle in the vertical orientation of FIG.

As shown in FIG. 1, the electrical junction box 10 includes a case 20 and a frame body 40 accommodated in the case 20 together with a circuit board (not shown).
The circuit board is obtained by mounting electronic components 12 such as a microcomputer and a semiconductor relay on a rectangular printed board in which a conductive path (not shown) is formed by a printed wiring technique. This circuit board is overlaid on the back side of the frame 40 and is screwed into a screw hole 58 (see FIG. 12) of the frame 40 by screws.

The case 20 is made of synthetic resin, and as shown in FIG. 1, has a flat rectangular tube shape in which a flat area 20 </ b> B having a large area is disposed opposite to the front and back, and an upper surface portion whose upper end is closed. 20A, and an opening 21 through which the frame body 40 can be inserted is formed at the lower end.
The upper surface portion 20A of the case 20 includes a fitting portion 22 to which a rectangular connector (not shown) is fitted and mounted, and a fuse mounting portion 32 to which a plurality of fuses are mounted, and these are arranged side by side. Has been.

The fitting portion 22 has a rectangular tube shape into which the connector can be fitted. The cylindrical protruding portion 24 protrudes upward from the upper surface portion 20A of the case 20 into a rectangular tube shape, and the lower portion from the upper surface portion 20A of the case 20. A lock recess 23 for receiving the distal end side of the lock arm of the connector protrudes on the inner surface of the fitting portion 22 on the inner surface of the fitting portion 22 (see FIG. 4). A recess is provided across the portion 24 and the cylindrical depression 25.
As shown in FIG. 9 showing the case 20 from the bottom surface side, the cylindrical depression 25 includes a rectangular cylindrical wall 26 and a flat bottom surface 29 provided at the lower end of the wall 26. The bottom surface portion 29 is formed with a rectangular insertion hole 30 through which one end sides of the plurality of terminal fittings 41A are collectively inserted. A recess is formed in the insertion hole 30 corresponding to the lock housing portion 23.

As shown in FIG. 4, the surrounding wall 26 extends in the left-right direction and faces a pair of facing walls 27A and 27B, and extends in the front-rear direction and connects a pair of side walls 28A and 27B. , 28 are connected in a ring shape.
The opposing walls 27A and 27B extend to the left and right substantially parallel to each other and substantially flat.
A bulging portion 31 that slightly protrudes from the outer surface is formed on the outer surface side of the rear facing wall 27B and on the outer surface side of the portion having the lock housing portion 23 on the inner surface side.

A large number of mounting holes 33 for mounting fuses are formed in the bottom surface of the fuse mounting portion 32.
Four (a plurality) V-shaped reinforcing ribs 35 extending in the vertical direction are arranged side by side on the rear surface of the case 20.
Note that locking claw portions 34 projecting downward from the upper surface portion 20 </ b> A are provided at both left and right ends of the case 20, and when the frame body 40 is accommodated in the case 20, The locking claw portion 34 is locked to the inner surface side of the locked claw portion 57 (see FIG. 12) erected at both ends in the direction.

As shown in FIG. 1, the frame body 40 includes a large number of terminal fittings 41 and a synthetic resin resin molded portion 42 that holds the numerous terminal fittings 41.
The terminal fittings 41 are L-shaped terminal fittings, which are arranged side by side on the upper and lower portions of the resin molding portion 42, and among these, the upper terminal fitting 41 is in the fitting portion 22 of the case 20. The terminal fitting 41 </ b> A protrudes and the terminal fitting 41 </ b> B arranged in the fuse mounting portion 32.

The resin molding part 42 is fitted with an intrusion prevention part 43 that holds the terminal fittings 41A, 41B at the upper part and prevents water from entering the circuit board side, and a mating connector (not shown) at the lower part. The connector part 50 which has the terminal metal fitting 41, and the connection part 52 which connects between the intrusion prevention part 43 and the connector part 50 provided in the intermediate part of the up-down direction are provided.
As shown in FIG. 10, the intrusion prevention unit 43 includes an inclined surface portion 44 (inclined surface) that guides water that has entered the upper surface of the frame body 40 to the left and right drainage through holes 56, and terminal fittings 41 </ b> A arranged side by side. A pair of water blocking walls 45A and 45B arranged to face each other with a predetermined interval so as to sandwich 41B.

As shown in FIG. 11, the inclined surface portion 44 has the highest middle portion in the left-right direction, and has a mountain shape that gently slopes from the middle portion toward the drainage through holes 56 provided at the left and right end portions, The end portion of the inclined surface portion 44 in the direction in which the inclination is lowered is continued to the upper end portion of the drainage through hole 56 that vertically penetrates the frame body 40. As shown in FIG. 10, the inclined surface portion 44 is slightly raised around the base end portions of the terminal fittings 41 </ b> A and 41 </ b> B protruding upward from the inclined surface portion 44.
The other ends of the terminal fittings 41A and 41B penetrating below the inclined surface portion 44 are bent at a right angle to the rear side at the lower side and inserted into the through holes of the circuit board disposed on the back surface side. Connected to the conductive path.

The water blocking walls 45 </ b> A and 45 </ b> B are raised from the front and rear end portions (front and rear edge portions) of the inclined surface portion 44, and when the frame body 40 is accommodated in the case 20, the outer surface side is the flat portion of the case 20. 20B is brought into contact with the inner surface, and the inner surface is brought into contact with the outer surface of the cylindrical depression 25.
Of the water blocking walls 45A and 45B, a part of the water blocking walls 45A and 45B is disposed on a portion (a portion on the right side in FIG. 10) facing the cylindrical depression 25 when the frame body 40 is accommodated in the case 20. The drainage cutout portions 46 and 47 are formed by being cut into thin walls.
Among these, as shown in FIG. 11, the notch 46 for drainage formed in the water stop wall 45A is formed by notching the upper side from the substantially middle part of the water stop wall 45A with a predetermined thickness. The stepped portion 46A at the lower end of the cutout portion 46 is formed substantially parallel to (in line with) the inclination of the inclined surface portion 44.

As shown in FIG. 12, the drainage cutout portion 47 formed in the other water stop wall 45B is formed by cutting out the upper side from a substantially middle portion in the vertical direction of the water stop wall 45B with a predetermined thickness. Since the thin wall portion 48 formed by thinly forming the water blocking wall 45B so as to be inserted through the bulging portion 31 of the cylindrical depression 25 is formed at a position corresponding to the bulging portion 31, In the portion, the drainage cutout 47 is divided.
A stepped portion 47A at the lower end of the drainage notch 47 is formed substantially parallel to the inclination of the inclined surface portion 44 (along the inclination).
As shown in FIG. 10, the reinforcing rib 35 of the case 20 is inserted into the outer surface side of the water blocking wall 45B when the frame body 40 is accommodated in the case 20 and the water blocking wall 45B receives the flat surface portion 20B. Possible insertion recesses 49 are formed corresponding to the positions of the reinforcing ribs 35.

The connector portion 50 can be fitted with a mating connector (not shown), and one end side (lower end side) of the terminal fitting 41 protrudes into the connector hood, and the other end of the terminal fitting 41 penetrating the connector portion 50. The end portion is bent upward at a right angle to the circuit board side and is inserted into the through hole of the circuit board to be connected to the conductive path of the circuit board.
As shown in FIG. 11, the connecting portion 52 is a portion where the intrusion preventing portion 43 and the connector portion 50 are divided and connected at four locations, and two beam portions provided at the left and right end portions of the frame body 40. And two beam portions provided on the inner side, and a part insertion hole 55 penetrating the front and back of the frame body 40 is formed between the beam portions. The component insertion hole 55 allows the electronic component 12 mounted on the circuit board to be inserted when the circuit board is mounted (see FIG. 1).

As shown in FIG. 11, drainage through holes 56 penetrating vertically are formed at the left and right ends of the frame body 40.
The drainage through hole 56 extends downward from the end (edge) of the inclined surface portion 44 and continues to the opening 56 </ b> A at the lower end of the frame body 40. Specifically, the end portion of the inclined surface portion 44 communicates with the lower portion through the inside of the connecting portion 52 and the side of the connector portion 50.

Next, the discharge of water that has entered the case 20 will be specifically described.
For some reason, water may enter the fitting portion 22, and water may enter the case 20 through the insertion hole 30 provided in the bottom surface portion 29 of the cylindrical depression 25.
In this case, the water that has entered normally falls to the inclined surface portion 44 that constitutes the drainage path below the insertion hole 30, as is apparent from FIG. The water dropped on the inclined surface portion 44 is guided to the end (edge) side where the inclined surface portion 44 is lowered, and reaches the drainage through hole 56, passes through the drainage through hole 56, and reaches the lower end portion of the frame body 40. It is discharged from the discharge port 56A.

However, the water that has entered through the insertion hole 30 may not be discharged downward from the inclined surface portion 44 and the drainage through hole 56 as described above.
Specifically, the water that has entered the fitting portion 22 passes through the insertion hole 30, travels along the back surface side of the bottom surface portion 29, and reaches the lower end portion of the surrounding wall 26 (opposing walls 27 </ b> A and 27 </ b> B). Here, the outer surface of the surrounding wall 26 (opposing walls 27A and 27B) and the inner surface of the water blocking walls 45A and 45B are opposed to each other in a substantially abutting state with a minute gap (see FIGS. 6 and 7).

  The water that has reached the lower end of the part where the surrounding wall 26 (opposing walls 27A and 27B) and the water blocking walls 45A and 45B are in contact with each other or have a slight gap is caused by capillary action. It is conceivable that the gap is raised and enters the side having the circuit board and the electronic component 12 beyond the water blocking walls 45A and 45B.

  However, in this embodiment, the water blocking walls 45A and 45B are provided with drainage cutout portions 46 and 47, and as shown in FIG. 8, the opposing wall 27A (27B) and the water blocking wall 45A are caused by capillary action. Even when water rises between (45B) (upward dotted arrow (i)), for the portion having the drainage cutout 46 (47), the opposing wall 27A (27B) and the water blocking wall 45A (45B) increases (see FIGS. 4 and 5), and water cannot rise due to capillary action.

  Therefore, as shown in FIG. 8, the water that has reached the drainage cutout 46 (47) travels along the step 46A (47A) to the lower end (right-pointed dotted arrow (ii)). Here, since the drainage notch 46 (47) is formed corresponding to the cylindrical recess 25, the cylindrical recess 25 (the surrounding wall 26) is formed at the end of the drainage notch 46 (47). ) Are not in contact with each other, and the water reaching the end of the drainage cutout 46 (47) descends from the waterstop wall 45A (45B) to the inclined surface 44 (downward dotted arrow ( iii)). When the inclined surface portion 44 is reached, the inclined surface portion 44 is led to the lower end side (right-pointing dotted line arrow (iv)) as usual, and when the drainage through hole 56 is reached, the drainage through hole 56 is passed through. Is discharged from the discharge port 56A at the lower end of the frame body 40.

According to this embodiment, the following effects can be obtained.
(1) Even when the water rises between the mutually facing surfaces of the cylindrical depression 25 and the water blocking walls 45A and 45B due to the capillary phenomenon, if the water reaches the drainage notches 46 and 47, the cylinder The gap between the recessed portion 25 and the water blocking walls 45A and 45B is increased so that the water does not rise, and the drainage path (the inclined surface portion 44 and the drainage through hole 56) passes through the drainage notches 46 and 47. It becomes possible to lead to. Therefore, it is possible to prevent water from entering the circuit board or the like beyond the water blocking walls 45A and 45B.

(2) Since the drainage cutout portions 46 and 47 are formed in the water blocking walls 45A and 45B, the drainage cutout portion 46 is generally formed rather than the drainage cutout portions 46 and 47 formed in the cylindrical depression 25. 47 can be easily formed.
(3) Of the water blocking walls 45A and 45B, when the drainage cutout portions 46 and 47 are formed in the thin wall portion 48 formed by the lock housing portion 23 and the bulging portion 31, the strength of the water blocking walls 45A and 45B is insufficient. However, according to the present embodiment, since the drainage notches 46 and 47 are formed so as to avoid the thin portion 48, it is possible to prevent the strength of the water blocking walls 45A and 45B from being insufficient.

(4) The drainage path includes an inclined surface portion 44 provided between the pair of water blocking walls 45A and 45B, and a drainage through hole 56 that extends to the end portion of the inclined surface portion 44 and penetrates the frame body 40 vertically. Since the water in the inclined surface portion 44 passes through the drainage through hole 56 and is discharged from the lower end of the drainage through hole 56 to the outside, the water can be efficiently discharged to the outside.
(5) Even if the notches of the drainage cutout portions 46 and 47 are inclined in any direction, it is possible to guide water to the drainage through hole 56 through the inclined surface portion 44. According to the above, since the drainage notches 46 and 47 are notched so as to be inclined in the direction along the inclined surface portion 44, water can be directly guided to the drainage through hole 56 via the inclined surface portion 44. .

<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.
(1) In the above embodiment, the drainage notches 46 and 47 are provided in the water blocking walls 45A and 45B, but may be provided in the cylindrical depression 25 as a reference example . Specifically, the drainage notch portion is, for example, upward from a predetermined height with respect to the outer peripheral surface (the outer peripheral surface of the surrounding wall 26) facing the water blocking walls 45A and 45B in the cylindrical depression 25. A notch may be formed.

  (2) The step portions 46A and 47A of the drainage cutout portions 46 and 47 are formed so as to be parallel to the inclined surface portion 44. However, the present invention is not limited to this. For example, the stepped portion of the drainage notch may be formed so as to be inclined to the opposite side of the inclined surface 44. Even in this case, the water reaching the inclined surface portion 44 passes through the water blocking walls 45A and 45B from the end of the stepped portion of the drainage notch, and the water reaching the inclined surface portion 44 is drained through-holes due to the inclination of the inclined surface portion 44 56.

  (3) The insertion hole 30 formed in the bottom surface portion 29 of the cylindrical depression 25 is for inserting the plurality of terminal fittings 41A all together, but the bottom portion is inserted according to the number of the terminal fittings 41A. A hole may be provided, and each terminal fitting 41A may be inserted into each insertion hole.

  (4) Although the drainage cutouts 46 and 47 are provided at substantially the middle position of the water blocking walls 45A and 45B, they may be provided at other height positions.

DESCRIPTION OF SYMBOLS 10 ... Electrical junction box 12 ... Electronic component 20 ... Case 20A ... Upper surface part 20B ... Plane part 22 ... Fitting part 24 ... Cylindrical protrusion 25 ... Cylindrical depression part 26 ... Enclosure wall 27A, 27B ... Opposite wall 28 ... Side wall Part 29 ... Bottom part 30 ... Insertion hole 31 ... Swelling part 40 ... Frame body 41 (41A, 41B) ... Terminal metal fitting 42 ... Resin molding part 43 ... Intrusion prevention part 44 ... Inclined surface part (inclined surface; drainage path)
45A, 45B ... Water blocking walls 46, 47 ... Drainage cutout portions 46A, 47A ... Stepped portion 48 ... Thin wall portion 56 ... Drainage through hole (drainage path)
56A ... Discharge port

Claims (3)

A circuit board, a synthetic resin frame that holds the circuit board and terminal fittings, and a rectangular tube fitting that can accommodate the circuit board and the frame body from the lower opening and that fits with a connector on the upper surface An electrical junction box comprising a case provided with a portion,
The fitting portion has a cylindrical recessed portion that is recessed with respect to the upper surface of the case, and an insertion hole through which one end side of the terminal fitting is inserted is formed in the bottom surface portion of the cylindrical recessed portion,
In the fitting portion, a lock accommodating portion for accommodating the distal end side of the lock arm of the connector is recessed, and a bulge portion is formed by the lock accommodating portion on the outer surface of the cylindrical depression,
The frame body is provided with a pair of water blocking walls facing the outer surface of the cylindrical depression in a state where the terminal fitting is inserted through the insertion hole,
Of facing surfaces of the cylindrical recess and the waterproofing wall, the surface of the water stop wall is cut-out portion for drainage formed to guide the water entering between the surface facing the drainage path ,
The water blocking wall is formed with a thin portion recessed at a position facing the bulging portion, and the drainage notch is formed so as to avoid the thin wall portion of the water blocking wall. An electrical junction box characterized by that. The drainage path is composed of an inclined surface provided between the pair of water blocking walls and a drainage through-hole that is connected to a terminal portion of the inclined surface and penetrates the frame body up and down. 2. The electrical junction box according to claim 1 , wherein water is discharged to the outside from the lower end of the drainage through hole through the drainage through hole . The electrical junction box according to claim 2, wherein the drainage cutout portion is cut out in an inclined shape in a direction along the inclined surface .

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