JP2011254657A - Electric connection box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric connection box capable of suppressing occurrence of failure on a circuit board or the like because of deformation of a case.SOLUTION: A case 20 of an electric connection box 10 includes a first counter wall 21 which faces a surface on the side opposite to a surface where an electronic component 11 of a circuit board 12 is mounted under such condition as the circuit board 12 and a frame 40 are stored. On a surface on the side of the first counter wall 21 in the frame 40, a receiving part 52 for receiving the first counter wall 21 and a substrate attaching part 55 which is recessed for the receiving part 52 and the circuit board 12 is attached, are formed. A reinforcing rib 30, extending in the inserting direction of the frame 40 and the circuit board 12, is formed at the position facing at least the circuit board 12, on the first counter wall 21.

Description

  The present invention relates to an electrical junction box.

Conventionally, as an example of an electrical connection box that is mounted on a vehicle such as a hybrid vehicle or an electric vehicle and performs energization or disconnection of an in-vehicle electrical component such as a lamp or an audio device, an electrical connection box described in Patent Document 1 is provided. Are known.
The electrical junction box accommodates a circuit board on which electronic components are mounted, a synthetic resin frame that is superimposed on a surface of the circuit board on which electronic components are mounted, a circuit board, and the frame. And a case.

JP 2009-290941 A

  By the way, in the above-described configuration, the surface of the circuit board opposite to the surface on which the electronic component is mounted faces the case wall. For this reason, when any force is applied to the wall of the case from the outside, the case may be deformed and the case and the circuit board may come into contact with each other, causing a problem or the like to the circuit board or an electronic component mounted on the circuit board. Is concerned.

  This invention is completed based on the above situations, Comprising: It aims at providing the electrical junction box which can suppress that a malfunction etc. arise in a circuit board etc. by the deformation | transformation of a case.

A circuit board on which an electronic component according to the present invention is mounted, a synthetic resin frame body superimposed on a surface of the circuit board on which the electronic component is mounted, and the circuit board and the frame body are opened. An electrical junction box that can be accommodated from a portion, wherein the case is opposite to a surface of the circuit board on which the electronic component is mounted in a state where the circuit board and the frame are accommodated. A first opposing wall facing the surface, and a receiving portion for receiving the first opposing wall on a surface of the frame on the first opposing wall side, and a recess provided with respect to the receiving portion. A board mounting portion on which the board is mounted is formed, and at least a portion of the first opposing wall facing the circuit board is provided with a reinforcing rib extending in the insertion direction of the circuit board and the frame body It is characterized in that is formed.
According to this configuration, since the first opposing wall of the case is reinforced by the reinforcing rib, even if an external force is applied to the first opposing wall of the case, the circuit board or the circuit board facing the first opposing wall It is possible to suppress the occurrence of defects in electronic components.

In addition, it is good also as following structures.
(1) There are a plurality of reinforcing ribs.
If it does in this way, the 1st counter wall can be reinforced more certainly.
(2) The reinforcing rib has a V shape in which a mountain-shaped top portion protrudes toward the circuit board.
If it does in this way, the intensity | strength of a reinforcement rib is securable with a simple structure.
Here, in order to increase the strength of the first facing wall, it is conceivable to make the reinforcing rib thick, but in that case, the space on the circuit board side may be limited by the reinforcing rib. On the other hand, according to this configuration, since the top portion protrudes toward the circuit board, it is easy to secure a space on the circuit board.

(3) A groove-like recess for receiving the reinforcing rib extends in the insertion direction in the receiving portion.
In this way, the groove-shaped recess can be used as a guide for the reinforcing rib, and erroneous insertion of the frame and the circuit board can be suppressed.
(4) The reinforcing rib is not formed in the vicinity of the opening.
In this way, it is possible to prevent the first opposing wall from being curved (inwardly warped).

(5) The end of the reinforcing rib on the opening side has an inclined portion in which the protruding dimension of the reinforcing rib increases in an inclined manner from the opening to the back.
If it does in this way, it will become possible to use a slope part as a guide at the time of accommodating a circuit board and a frame.
(6) A thin portion that reduces the thickness dimension of the frame is formed at a corner on the front end side in the insertion direction of the opening in the frame.
Thus, by forming the thin part which reduces the thickness dimension of a frame, insertion to a case of a circuit board and a frame can be made easy.

(7) The case includes a second opposing wall facing the surface of the frame opposite to the surface having the substrate mounting portion, and the second opposing wall of the frame A projecting ridge is formed on the opposing surface so as to protrude at a height capable of contacting the second opposing wall.
In this way, even when an external force is applied to the second opposing wall of the case, the case can be prevented from deforming by contacting the ridge.

  It is possible to suppress the occurrence of problems such as a circuit board due to deformation of the case of the electrical junction box.

1 is an exploded perspective view of an electrical junction box according to Embodiment 1. FIG. 1 is a perspective view showing a state in which the circuit board of FIG. 1 is mounted on a frame. Perspective view representing the electrical junction box Rear view showing electrical junction box Bottom view showing electrical junction box AA sectional view showing an electrical junction box Rear view showing the case Side view showing the case BB side sectional view showing the case Plan view showing the case Rear view showing the circuit board mounted on the frame Side view showing a state where the circuit board is mounted on the frame A plan view showing a state where a circuit board is mounted on a frame Bottom view showing the circuit board mounted on the frame Rear view showing the frame

<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) and in-vehicle electrical components (not shown) such as a lamp and a horn, and executes energization and disconnection of the in-vehicle electrical components. In the following description, the vertical direction and the horizontal direction will be described with reference to FIG. 4, with the back side of FIG. 4 being the front side and the front side of the paper side being the back side.

As shown in FIG. 1, the electrical junction box 10 includes a circuit board 12 on which the electronic component 11 is mounted, a case 20, and a frame body 40 that is accommodated in the case 20 together with the circuit board 12.
The circuit board 12 is obtained by mounting an electronic component 11 such as a microcomputer or a semiconductor relay on a rectangular printed board that forms a conductive path (not shown) by a printed wiring technique. The terminals of the electronic component 11 are connected to the conductive path on the front side of the circuit board 12 by soldering.

A pair of screw holes 13 through which the screws 14 can be inserted are provided at diagonal positions of the corners of the circuit board 12, and the surface of the circuit board 12 on which the electronic component 11 is mounted is the frame body 40. The circuit board 12 is fixed to the frame body 40 with screws 14 in a superposed state.
The circuit board 12 is provided with a large number of through holes 15 penetrating the circuit board 12, and the terminal fittings 41 of the frame body 40 are inserted into the through holes 15 and soldered, whereby It is electrically connected to the conductive path (see FIG. 6).

  Note that when the frame body 40 to which the circuit board 12 is mounted is accommodated in the case 20, the tip end portion 41 </ b> A of the terminal fitting 41 does not come into contact with the inner surface (first opposing wall 21) of the case 20 from the back surface of the circuit board 12. While projecting at a height, the head of the screw 14 projects from the back surface of the circuit board 12 at a height that does not contact the inner surface of the case 20.

The case 20 is made of a synthetic resin and has a flat rectangular tube shape whose upper part is closed by a connecting part 24 as shown in FIG.
More specifically, the case 20 includes a first opposed wall 21 that is flat and has a large area, a second opposed wall 22 that is disposed opposite to the first opposed wall 21, and the first opposed wall 21 and the second opposed wall 22. Are provided with a pair of side walls 23 and 23 and a connecting portion 24 provided at the upper portion, and an opening 25 is formed at the lower end portion through which the frame body 40 and the circuit board 12 can be inserted.

The connection portion 24 includes a hood portion 26 to which a connector (not shown) is attached and fuse attachment portions 27A and 27B to which a plurality of fuses are attached, and these are arranged side by side.
As shown in FIG. 10, a rectangular terminal insertion hole 26 </ b> A is formed inside the hood portion 26. A large number of mounting holes 27C are formed in the bottom surfaces of the fuse mounting portions 27A and 27B.

  When the frame body 40 is accommodated in the case 20, among the terminal group (terminal fitting 41) provided on the upper portion of the frame body 40, a plurality of power terminals are inserted into the terminal insertion holes 26 </ b> A to The fuse connection terminals are arranged in the respective mounting holes 27C so that the fuses can be mounted.

The first opposing wall 21 and the second opposing wall 22 have the same area and are substantially rectangular, and the lower ends of the first opposing wall 21 and the second opposing wall 22 are both side walls 23, as shown in FIG. As shown in FIG. 9, the opening portions 25 of the first opposing wall 21 and the second opposing wall 22 are notched on an arc. It is.
Both side portions of the extending portions 21A, 22A are cut out so that the width dimension of the extending portions 21A, 22A becomes narrower toward the lower end side.

Here, of the opposing walls 21 and 22, only the first opposing wall 21 is formed with four (plural) reinforcing ribs 30 extending in the vertical direction (the insertion direction of the frame body 40 with respect to the case 20). Yes.
The shape of the reinforcing rib 30 has a V shape in which the top of the mountain shape protrudes toward the circuit board 12 (see FIG. 6), whereby the outer surface side of the first opposing wall 21 is recessed in a groove shape.
As shown in FIG. 9, each reinforcing rib 30 has a length from the upper end (the upper end of the case 20) to the lower end of the first opposing wall 21 to a predetermined position above the opening edge portion 28 of the first opposing wall 21. The heights of the lower ends of all the reinforcing ribs 30 are the same.

  The position in the width direction of each reinforcing rib 30 is formed at both end portions in the left-right direction, the boundary portion between the hood portion 26 and the fuse mounting portion 27B, and the boundary portion between the fuse mounting portion 27A and the fuse mounting portion 27B. The three on the right side are formed at approximately equal intervals, but the two on the left side are slightly wider.

The lower end of the reinforcing rib 30 (the end on the opening 25 side) is such that, on the inner surface side of the first opposing wall 21, the protruding dimension of the reinforcing rib 30 faces upward (from the opening to the back of the case). And an inclined portion 30A that increases in an inclined manner.
Thus, the vicinity of the opening 25 (and the opening edge 28) (generally the portion of the extending portion 21A) is a flat portion 31 on which the reinforcing rib 30 is not formed.
The reinforcing rib 30 is formed by providing a projection for forming the reinforcing rib 30 on a mold used when the case 20 is formed.
Further, both ends of the connecting portion 24 are provided with locking claws 33 protruding inward of the case 20, and both ends of the terminal holding portion 42 when the frame body 40 is accommodated in the case 20. It is locked to the inner surface side of the locked portion that is erected.

  As shown in FIG. 1, the frame body 40 is formed by molding a large number of L-shaped terminal fittings 41 with a synthetic resin material. The frame body 40 is provided on the upper portion of the frame body 40 and is connected to the connection portion 24 of the case 20. The terminal holding part 42 to be mounted, the connector part 45 provided at the lower part of the frame body 40 to be fitted with the mating connector, and the terminal holding part 42 provided at the intermediate part in the vertical direction are connected to the connector part 45. And a connecting portion 47.

The terminal holding portion 42 protrudes into a pair of partition walls 43 and 43 in which end portions 41B of the terminal fittings 41 are opposed to each other in parallel. The other end 41A of the terminal fitting 41 penetrating the terminal holding portion 42 is bent at a right angle toward the circuit board 12 and is inserted into the through hole 15 of the circuit board 12 to be connected to the conductive path (FIG. 6). reference).
The connector part 45 can be fitted to a mating connector (not shown), and one end side 41B of the terminal fitting 41 protrudes into the hood part 46 (see FIG. 14).
The other end 41A of the terminal fitting 41 penetrating the connector portion 45 is bent at a right angle toward the circuit board 12 and is inserted into the through hole 15 of the circuit board 12 to be connected to the conductive path.

As shown in FIG. 15, the connecting portion 47 is a portion that connects the terminal holding portion 42 and the connector portion 45 separately at four locations, and is provided with two beam portions provided at the left and right end portions of the frame body 40. 48 and two beam portions 48 provided on the inner side thereof, and an insertion hole 49 penetrating the front and back of the frame body 40 is formed between the beam portions 48. The insertion hole 49 allows the electronic component 11 mounted on the circuit board 12 to be inserted when the circuit board 12 is mounted.
Of the upper part of the frame body 40, at the end portion in the width direction (corner portion on the front end side in the direction of insertion into the opening), as shown in FIG. 1, the thickness of the frame body 40 at this end portion (corner portion). A thin portion 50 having a reduced size is formed. Of the thin portion 50, the partition wall 43 is formed by disposing the partition wall 43 slightly inwardly in a step shape.

On the front surface side (front side) of the frame body 40, protrusions 51 are formed so as to protrude from the hole edge portion of the insertion hole 49, the edge portion of the beam portion 48, the boundary portion with the connector portion 45 and the like. Among these, the protrusion part 51 provided in the boundary part with the connector part 45 is formed intermittently.
The projecting height of the protrusion 51 is substantially the same as the front-side partition wall 43 (excluding the thin portion 50) and the left and right end beam portions 48 (excluding the thin portion 50). When the body 40 is accommodated in the case 20, as shown in FIG. 6, these protrusions 51 have almost no gap (or a slight gap) with respect to the inner surface of the second opposing wall 22 of the case 20. It has a height that allows contact.

As shown in FIG. 15, a receiving portion 52 that receives the first opposing wall 21 in a contact state when the frame body 40 is housed in the case 20 and the circuit board 12 are mounted on the rear surface side (back side) of the frame body 40. A substrate mounting portion 55 is formed.
The receiving part 52 is formed in the upper part and the lower part of the rear surface of the frame body 40 (bulging formation), and the upper side has the outer surface of the partition wall 43 on the rear surface side as the receiving part 52A, and the lower part side The portions that continue below the beam portions 48 at both ends are the receiving portions 52B. A connector portion 45 is disposed between the receiving portions 52B provided at the left and right end portions.
In the receiving portion 52A, a groove-like concave portion 53 that receives the reinforcing rib 30 extends in the vertical direction (the direction in which the frame body 40 is inserted into the case 20).

Four groove-like recesses 53 are formed at positions corresponding to the reinforcing ribs 30 of the case 20, and as shown in FIG. 6, the cross-sections of these groove-like recesses 53 are formed in an arcuate shape. Yes.
As shown in FIG. 15, the groove-shaped recess 53 is formed by recessing the rear surface side (the outer surface of the partition wall 43 on the rear surface side) in the upper part of the frame body 40 into a groove shape.
In addition, since the connector part 45 (the hood part 46) is arranged close to the front side of the frame body 40, the rear surface of the hood part 46 is positioned lower than the receiving part 52, thereby at least A space for the height through which the reinforcing rib 30 is inserted is secured (the back surface side of the hood portion 46 is formed at a position (frontward) lower than the bottom surface of the groove-shaped recess 53).
Through holes 54 penetrating vertically are formed in the left and right ends of the frame body 40 (portions including the beam portions 48 and the receiving portions 52B at the ends) (see FIG. 6). Moisture adhering to the bottom surface of the terminal holding portion 42 passes through the bottom surface, passes through the through hole 54, and is discharged below the frame body 40.

As shown in FIG. 15, the board mounting portion 55 has a rectangular shape sandwiched between upper and lower receiving portions 52 and recessed from the receiving portion 52 (thinner than the receiving portion 52). It is a region and is formed over almost the entire width of the frame body 40.
An enclosing wall 56 for holding the circuit board 12 at a predetermined position on the inner side is formed on the side edge in the width direction at the upper part of the board mounting part 55.

  In the region of the substrate mounting portion 55, a boss portion 57 is provided at a diagonal position of the corner portion. The circuit board 12 is mounted on the frame body 40 by inserting the electronic component 11 through the insertion hole 49 and screwing the screw into the screw hole 13 and the boss portion 57 of the circuit board 12 (see FIG. 11). ).

  As shown in FIG. 2, with the circuit board 12 mounted on the frame body 40, the terminal body 42 side of the frame body 40 faces up, and the surface of the frame body 40 on the circuit board 12 side reinforces the case 20. It is arranged on the first opposing wall 21 side where the rib 30 is formed, and is accommodated in the case 20 from one side of the thin portion 50 formed at the end in the width direction of the frame body 40 (the width of the frame body 40). The frame body 40 is inclined and inserted into the case 20 so that the thin portion 50 on one end side in the direction approaches the opening 25). Thus, since the thickness dimension of the frame 40 is slightly thin on the side having the thin portion 50, the frame 40 can be easily inserted into the case 20. Then, when the frame body 40 with the circuit board 12 mounted is accommodated in a predetermined position of the case 20, as shown in FIG. 6, the distance between the circuit board 12 and the first opposing wall 21 is a predetermined dimension (circuit board 12). The terminal fitting 41 and the screw 14 projecting to the back surface side are arranged so as to face each other in a state where they are separated from each other. At this time, the positions of the terminal fittings 41 and the screws 14 on the back surface side of the circuit board 12 are arranged at positions avoiding the positions facing the reinforcing ribs 30 (the terminal fittings 41 and the screws 14 do not face the reinforcing ribs 30). ).

According to this embodiment, the following effects can be obtained.
(1) Even when the first opposing wall 21 of the case 20 receives an external force or the like, the first opposing wall 21 is reinforced by the reinforcing ribs 30, so that the circuit board 12 or the circuit board facing the first opposing wall 21 It is possible to suppress the occurrence of a defect or the like in the electronic component 11 on the twelve.

(2) Since there are a plurality of reinforcing ribs 30, the first opposing wall 21 can be more reliably reinforced.
(3) Since the reinforcing rib 30 has a V shape in which the peak of the mountain shape protrudes on the circuit board 12 side, the strength of the reinforcing rib 30 can be secured with a simple configuration.
Here, in order to increase the strength of the first opposing wall 21, it is conceivable to increase the thickness of the reinforcing rib 30, but in that case, the space on the circuit board 12 side may be limited by the reinforcing rib 30. On the other hand, according to the configuration of the present embodiment, the top portion protrudes on the circuit board 12 side, so that it is easy to secure a space on the circuit board 12 side.

(4) Since the groove-like recess 53 for receiving the reinforcing rib 30 extends in the vertical direction (insertion direction) in the receiving portion 52, the groove-like recess 53 can be used as a guide for the reinforcing rib 30. Incorrect insertion of the body 40 and the circuit board 12 can be suppressed.
(5) Since the reinforcing rib 30 is not formed in the vicinity of the opening 25, the first opposing wall 21 can be prevented from being bent (inwardly warped).

(6) The end portion on the opening 25 side of the reinforcing rib 30 has the inclined portion 30A in which the protruding dimension of the reinforcing rib 30 increases in an inclined manner from the opening 25 side toward the back side. It can be used as a guide when the substrate 12 and the frame body 40 are accommodated.
(7) Since the thin portion 60 that reduces the thickness dimension of the frame body 40 is formed in the corner portion of the frame body 40 on the front end side in the insertion direction into the opening 25, the circuit board 12 and the frame body Forty insertions into the case 20 can be facilitated.

(8) The case 20 has the second opposing wall 22 facing the surface of the frame body 40 opposite to the surface having the substrate mounting portion 55, and the second opposing wall 22 of the frame body 40. Is formed on the surface facing the second opposed wall 22 at a height that can contact the second opposed wall 22, so that even if an external force is applied to the second opposed wall 22 of the case 20, The deformation of the case 20 can be prevented by the two opposing walls 22 coming into contact with the ridges 51.

<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) The number of the reinforcing ribs 30 may be a plurality of numbers other than the four in the above embodiment, or may be a single number.
(2) The shape of the reinforcing rib 30 is not limited to the V shape, and may be other shapes. For example, a reinforcing rib 30 that is at least thicker on the circuit board 12 side in the first opposing wall 21 may be provided.

  (3) The reinforcing rib 30 is provided over the entire height of the first opposing wall 21 except for the vicinity of the opening 25, but is not limited thereto. For example, a reinforcing rib may be provided only in a region of the first facing wall 21 that faces at least the circuit board 12, and a reinforcing rib may not be provided in a region that faces the receiving portion 52.

DESCRIPTION OF SYMBOLS 10 ... Electrical junction box 11 ... Electronic component 12 ... Circuit board 14 ... Screw 20 ... Case 21 ... 1st opposing wall 22 ... 2nd opposing wall 24 ... Connection part 25 ... Opening part 26 ... Hood part 27A, 27B ... Fuse mounting part DESCRIPTION OF SYMBOLS 30 ... Reinforcement rib 40 ... Frame 41 ... Terminal metal fitting 49 ... Insertion hole 50 ... Thin part 51 ... Projection part 52 ... Receiving part 53 ... Groove-shaped recessed part 55 ... Substrate mounting part

Claims (8)

A circuit board on which electronic components are mounted, a synthetic resin frame that is superimposed on a surface of the circuit board on which the electronic components are mounted, and the circuit board and the frame can be accommodated from the opening. An electrical junction box comprising a case,
The case has a first opposing wall that faces a surface of the circuit board opposite to a surface on which the electronic component is mounted in a state where the circuit board and the frame are accommodated.
A receiving part that receives the first opposing wall and a board mounting part that is recessed with respect to the receiving part and on which the circuit board is mounted are formed on the surface of the frame on the first opposing wall side. And
An electrical junction box, wherein a reinforcing rib extending in an insertion direction of the circuit board and the frame is formed at least in a portion of the first facing wall facing the circuit board. The electrical junction box according to claim 1, wherein a plurality of the reinforcing ribs are provided. The electrical connection box according to claim 1, wherein the reinforcing rib has a V shape in which a mountain-shaped top portion protrudes toward the circuit board. The electrical connection box according to any one of claims 1 to 3, wherein a groove-shaped recess for receiving the reinforcing rib extends in the insertion direction in the receiving portion. 5. The electrical junction box according to claim 1, wherein the reinforcing rib is not formed in the vicinity of the opening. 6. The end portion on the opening side of the reinforcing rib has an inclined portion in which the protruding dimension of the reinforcing rib increases in an inclined manner from the opening side toward the back side. The electrical junction box according to any one of 5. The thin part which makes the thickness dimension of the said frame small is formed in the corner | angular part in the front end side of the insertion direction to the said opening part among the said frame, The 1 thru | or 6 characterized by the above-mentioned. The electrical junction box according to any one of the above. The case has a second facing wall facing the surface of the frame opposite to the surface having the substrate mounting portion.
The ridge part protruded by the height which can contact | abut to the said 2nd opposing wall is formed in the surface facing the said 2nd opposing wall among the said frame bodies, The thru | or 1 characterized by the above-mentioned. The electrical junction box according to claim 7.

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