JP5811986B2 - Electrical junction box - Google Patents

Description

  The present invention relates to an electrical junction box.

  2. Description of the Related Art Conventionally, an electrical junction box that is grounded to a vehicle body is known.

  In the electrical junction box of Patent Document 1, an FET and a control circuit board are accommodated inside a case composed of a case and a cover, and these are arranged on a heat dissipation member formed by extruding and molding a metal having high thermal conductivity. .

JP 2002-315148 A

  By the way, in order to prevent noise emission of the electronic components in the case, it is conceivable that the case and the heat radiating member of the electrical junction box are connected to the ground to cause a shield function in the case and the heat radiating member. In this case, when the structure which connects a case and a heat radiating member to a ground separately is provided, there exists a problem that the structure of an electrical junction box tends to become complicated.

  The present invention has been completed based on the above circumstances, and an object thereof is to simplify the configuration of an electrical junction box.

  The present invention is an electrical connection box mounted on a vehicle, comprising: a circuit unit on which electronic components are mounted; a conductive heat radiating member that dissipates heat from the circuit unit; and the circuit unit including the heat radiating member. A conductive case housed in between, and a relay ground terminal having a ground connection portion connected to the ground of the vehicle, wherein the relay ground terminal is connected to the heat dissipation member, A second connection portion connected to the case.

  According to this configuration, since the relay ground terminal connected to the ground of the vehicle is connected to the heat dissipation member and the case by the first connection portion and the second connection portion, both the heat dissipation member and the case are electrically connected to the vehicle ground. It becomes possible to connect to. Therefore, the configuration of the electrical junction box can be simplified as compared with the case where the case and the heat dissipation member are individually connected to the ground.

It is preferable to have the following configuration as an embodiment of the above configuration.
-The case is provided with a shield connection part protruding outward, and the second connection part is connected to the shield connection part.
By connecting the shield connection portion projecting outward from the case of the electrical junction box to the second connection portion as in this configuration, the case can be connected to the ground potential with a simple configuration.

-The said heat radiating member is formed by extrusion molding, and the said 1st connection part is connected to the surface by the side of the said circuit part of the said heat radiating member.
When the heat radiating member is formed by extrusion molding, it is not easy to process the shape such as projecting a portion connected to the first connection portion. According to this configuration, even if the heat dissipation member is extruded, the first connection portion of the relay ground terminal and the surface of the heat dissipation member on the circuit portion side are connected, so the heat dissipation member can be grounded with a simple configuration. It becomes possible to connect to a potential.

A frame-shaped member is assembled on the heat radiating member side, and an insertion portion through which the first connection portion is inserted is formed in the frame-shaped member.
When the frame member is assembled to the heat radiating member, there may be a case where it is not easy to assemble the relay ground terminal to the heat radiating member because of the frame member. Even in the configuration including the relay ground terminal, the first connection portion can be inserted into the insertion portion.

The frame-shaped member has a mounted portion that is attached to the mounting portion of the vehicle, and the ground connection portion is arranged on the mounted portion.

The relay ground terminal is formed by bending a metal plate material.
In this way, the configuration of the relay ground terminal can be simplified.

  According to the present invention, the configuration of the electrical junction box can be simplified.

Perspective view showing electrical junction box An enlarged plan view showing a part of the electrical junction box AA sectional view of FIG. Top view showing the electrical junction box with the case removed BB sectional view of FIG. CC sectional view of FIG. DD sectional view of FIG. EE sectional view of FIG. Disassembled perspective view of electrical junction box Drawing showing the state where the relay ground terminal is assembled to the heat dissipation member The figure for demonstrating a mode that a frame-shaped member is assembled | attached to a thermal radiation member Diagram for explaining assembly of ground terminal The figure which shows the state in which the circuit part of the state which does not have one circuit board on the heat radiating member was mounted | worn

<Embodiment 1>
The electrical junction box 10 of Embodiment 1 is demonstrated referring FIG. 1 thru | or FIG.
The electric junction box 10 (FIG. 1) is mounted on a path from a battery (power source) to a load in a vehicle (not shown) such as an electric vehicle or a hybrid vehicle. In the following description, the vertical direction will be described with reference to FIG. 3, and the front-back direction will be described with the left side of FIG.

  As shown in FIG. 9, the electrical junction box 10 includes a circuit unit 11 having a pair of circuit boards 13 </ b> A and 13 </ b> B, and a conductive heat dissipating member 20 disposed under the circuit unit 11 to dissipate heat from the circuit unit 11. A relay having a conductive case 25 for housing the circuit portion 11 between the heat dissipation member 20, a frame-like member 45 mounted on the heat dissipation member 20, and a ground connection portion 34 connected to the ground of the vehicle. And a ground terminal 33.

  The circuit unit 11 includes two circuit boards 13A and 13B arranged to face each other. A plurality of electronic components 12 are mounted on the circuit unit 11 (circuit boards 13A and 13B).

A bus bar 14 made of a metal plate is overlaid on the lower circuit board 13A.
As shown in FIG. 13, the electronic component 12 includes a choke coil, a capacitor, a relay, and the like, and the terminals of each electronic component 12 are connected to the conductive path of the circuit board 13 </ b> A and the bus bar 14.
A plurality of terminal portions 15 protrude from the peripheral edge portion of the circuit portion 11.

  The plurality of terminal portions 15 are provided with a pair of connector terminals 16A and 16B constituting a connector to which an external power supply side connector is connected by mounting a connector housing 51 that opens in a hood shape, and two circuit boards 13A and 13B. And a board relay terminal 19 for connecting between them.

The connector terminals 16 </ b> A and 16 </ b> B protrude into the connector housing 51 through a back wall that closes the inside of the connector housing 51.
In the pair of connector terminals 16A and 16B, the connector terminal 16B is connected to the positive side of a power source such as a battery, and the connector terminal 16A is connected to the negative side of the power source.

Between the connector terminal 16A and the bus bar 14, it extends in a direction orthogonal to the connector terminal 16A and is bent in a crank shape, and its lower end is extended from the bus bar 14 so as to be exposed from the circuit boards 13A and 13B. It is raised from the edge of the extension part 17.
A circular connection hole 18 is formed in the extending portion 17 so as to penetrate through the screw hole 22 of the heat radiating member 20. Thereby, the connector terminal 16 </ b> A is electrically connected to the relay ground terminal 33 through the heat dissipation member 20.

  The heat dissipating member 20 is integrally formed of a metal material having high thermal conductivity such as an aluminum alloy or a copper alloy, and as shown in FIG. 10, the upper surface is a mounting surface on which the circuit unit 11 is mounted. 21 and is flat over the entire surface. A large number of comb blade-shaped heat radiation fins 20A are formed on the bottom surface side, and the entire heat radiation member 20 is integrally formed by extrusion molding.

  The mounting surface 21 has a screw hole 22 communicating with the connection hole 18 of the bus bar 14, a pair of screw holes 23, 23 communicating with the through holes 41, 41 of the first connection part 40 of the relay ground terminal 33, and a frame A fixing screw hole 24 for fixing the shaped member 45 is formed.

By screwing a screw (not shown) through the connection hole 18 of the bus bar 14 into the screw hole 22, the extending portion 17 is fixed to the heat radiating member 20, and the connector terminal 16 </ b> A and the heat radiating member 20 are electrically connected. Connected.
The pair of screw holes 23, 23 are formed at the front end of the heat dissipation member 20.
The fixing screw holes 24 are formed at the four corners of the placement surface 21.

  The case 25 is formed by drawing or punching and bending a metal plate material such as an electrogalvanized steel plate, as shown in FIG. Four side walls 27 extend downward from the edge of the rectangular top plate portion 26.

On the four side walls 27, locking pieces 28 that can be bent and deformed outward are formed by cutting out the side walls 27.
A rectangular locking hole 29 that extends in the circumferential direction passes through the locking piece 28.

In the middle portion in the width direction of the side wall 27 on the front side, a cutout portion 27A cut out in a rectangular shape according to the shape of the attached portion 52 is formed, and at the lower end of the side wall 27 in the vicinity of the cutout portion 27A, A shield connection portion 30 protruding outward is formed.
The shield connection portion 30 has a rectangular shape and extends outward from the lower end edge of the side wall 27 orthogonally, and a circular through hole 31 is formed at the center.

  The relay ground terminal 33 is obtained by, for example, punching a metal plate material of copper, copper alloy, aluminum, or aluminum alloy into a developed shape and performing bending (pressing), and is connected to the ground potential of the vehicle. 34, a first connection portion 40 connected to the heat dissipation member 20, a connection portion 37 connecting the ground connection portion 34 and the first connection portion 40, and a second connection connected to the case 25 connected to the first connection portion 40. The connecting portion 42 is integrally formed.

The ground connection portion 34 has a long rectangular shape on the front side, and a circular attachment hole 35 is formed through the front end side.
A rectangular positioning hole 36 for positioning at a predetermined position of the relay ground terminal 33 is formed behind the mounting hole 35.

  The connecting portion 37 includes a first side edge portion 38 that rises in an L shape from the side edge of the flat ground connection portion 34, and a side opposite to the ground connection portion 34 side from the rear end of the first side edge portion 38. And a second side extension 39 extending in the direction, and a first connection portion 40 extending rearward from the upper end of the second side extension 39 at a right angle is formed.

The 1st connection part 40 is mounted in the front-end part of the mounting surface 21 in the heat radiating member 20, and makes long rectangular shape in the left-right direction.
The first connection portion 40 is formed with a pair of left and right circular through holes 41, 41. When the relay ground terminal 33 is arranged at the assembly position of the heat radiating member 20 (FIG. 10), the pair of through holes 41 and 41 overlap the pair of screw holes 23 and 23 of the heat radiating member 20.

  The second connection portion 42 has an L shape, extends from the side edge of the first connection portion 40 to the side, and then extends to the front side. A circular through hole 43 is formed.

  As shown in FIG. 11, the frame-shaped member 45 is fixed to a frame main body 46 that covers the outer peripheral portion of the heat radiating member 20 and a mounting portion (not shown) of the vehicle that protrudes outward from the periphery of the frame main body 46. A mounted portion 52 and a mounting fixing portion 58 are provided.

  The frame body 46 has a rectangular shape, and a portion where the electronic component 12 is disposed is defined, and boss portions 47 for screwing the circuit board 13B are formed at the four corner positions.

  A slit-like insertion hole 48 (an example of an “insertion portion”) for inserting the relay ground terminal 33 from the first connection portion 40 side passes through the frame body 46 in the front-rear direction. The insertion hole 48 has a size (vertical and horizontal dimensions) that allows insertion of substantially the entire first connection portion 40 and the proximal end side of the second connection portion 42 into the frame body 46.

On the outer periphery of the frame main body 46, locking projections 49 that are locked in the locking holes 29 of the locking pieces 28 and hold the case 25 in a closed state are formed at intervals over the entire circumference. .
The locking projection 49 has a shape in which the lower end protrudes outwardly in a stepped shape and the protruding dimension decreases in an inclined manner upward.

  When the case 25 is covered, the locking piece 28 comes into contact with the inclined portion of the locking projection 49 to bend the locking piece 28. When the locking hole 29 reaches the stepped portion, the locking piece 28 is elastically restored. Thus, the stepped portion of the locking projection 49 is locked to the hole edge of the locking hole 29.

The frame main body 46 has a cover portion 50 that covers the fins 20 </ b> A of the heat radiating member 20 formed in a comb-like shape below.
The frame main body 46 is formed with a terminal holding portion for holding the terminal 16C on the upper surface.
In the frame main body 46, at positions corresponding to the screw holes 23 of the heat radiating member 20, a through hole 46A through which a tool for screwing can be inserted is formed.

The side wall 61 on the front side is formed with a base 53 that slightly protrudes and extends downward to the height of the lower end of the heat radiating member 20, and the attached portion 52 that extends outward is formed at the lower end of the base 53. Is provided.
The attached portion 52 is a portion that is attached to the attachment portion of the vehicle, and is arranged in the middle portion in the left-right direction of the side wall 61 on the front side, and the ground connection portion 34 is in close contact with the bottom surface of the attached portion 52. Arranged.

A mounting hole 53 is formed in the mounted portion 52, and a collar 54 made of a cylindrical metal is fitted into the mounting hole 53.
As shown in FIG. 5, a positioning projection 55 is formed on the bottom surface of the mounted portion 52 so as to be locked in the positioning hole 36 of the ground connection portion 34 and prevent the relay ground terminal 33 from coming off.

  The positioning protrusion 55 has a stepped portion 55A whose rear end protrudes downward in a stepped shape, and an inclined surface 55B whose protruding size decreases in an inclined shape toward the front side. When the relay ground terminal 33 is inserted into the insertion hole 48, the upper surface of the ground connection portion 34 is in sliding contact with the inclined surface 55 </ b> B of the positioning projection 55, and when the relay ground terminal 33 is inserted to a position where it stops before, the positioning hole 36 is formed. The relay ground terminal 33 is positioned by reaching the stepped portion 55A and retaining the hole edge of the positioning hole 36 with the stepped portion 55A against the force in the separating direction.

As shown in FIG. 9, a holding portion 56 for holding the second connection portion 42 and the nut 44 is integrally connected to the side of the base portion 53 on the second connection portion 42 side of the base portion 53.
The holding portion 56 is formed with an accommodation recess 57 in which the hexagonal nut 44 is accommodated.

  The accommodating recess 57 is formed in a hexagonal shape according to the shape of the nut 44. When the nut 44 is accommodated in the accommodating recess 57, the nut 44 is rotated (during screwing) by the inner peripheral shape of the accommodating recess 57. Co-rotation) is regulated.

The attachment fixing portion 58 is provided at a tip portion of a portion extending obliquely upward from the side wall 61 opposite to the side having the attached portion 52 in the frame main body 46.
An attachment hole 59 is formed in the attachment fixing portion 58, and a collar 60 made of a cylindrical metal is fitted in the attachment hole 59.

The assembly of the electrical junction box 10 will be described.
An adhesive is applied to a region excluding the vicinity of the screw holes 22 and 23 and the fixing screw hole 24 (an area where the first connection portion 40 and the like are arranged) on the mounting surface 21 of the heat radiating member 20. Curing is performed to form an insulating layer.

And an adhesive agent is apply | coated on an insulating layer, the frame-shaped member 45 is covered on the heat radiating member 20 (FIG. 11), and the frame-shaped member 45 is screwed to the heat radiating member 20 (FIG. 12).
And the relay ground terminal 33 is inserted in the insertion hole 48 of the frame-shaped member 45 from the 1st connection part 40 side (FIG. 13).

Then, in the relay ground terminal 33 inserted into the insertion hole 48 of the frame-shaped member 45, the connecting portion 37 stops at the side wall 61 at the position where the first connection portion 40 is disposed in the through-hole 46 </ b> A of the frame-shaped member 45. In addition, the positioning protrusion 55 enters the positioning hole 36 and is locked, the ground connection portion 34 overlaps the attached portion 52, and the relay ground terminal 33 is in a normal position with respect to the frame-shaped member 45. Installed (FIG. 5).
At this time, the through hole 43 of the second connection portion 42 is continuous with the screw hole of the nut 44 housed in the housing recess 57 (FIG. 6), and the through holes 41 and 41 of the connection hole 18 are a pair of screw holes 23 and 23. (FIGS. 8 and 10)).
Then, the nut 44 and the screw holes 23 and 23 are screwed (or bolted) through the through holes 41 and 43. Thereby, the relay ground terminal 33 is electrically connected to the heat dissipation member 20.

Next, the other circuit board 13 </ b> B is connected to the board relay terminal 19 so as to face one circuit board 13 </ b> A of the circuit unit 11.
When the case 25 is placed on the heat dissipation member 20, the locking piece 28 of the case 25 is locked to the locking projection 49. At this time, the shield connection part 30 of the case 25 is overlaid on the holding part 56 and the nut 44 so that the through hole 31 is continuous with the through hole 43 of the second connection part 42 (FIGS. 1 and 3).

The shield connection part 30 and the second connection part 42 are screwed to the nut 44 through the through holes 31 and 43.
Thereby, the case 25 and the relay ground terminal 33 are electrically connected. At this time, the relay ground terminal 33 is electrically connected to both the case 25 and the heat dissipation member 20.
And if the to-be-attached part 52 is attached to the attachment part of a vehicle, the ground connection part 34 will contact the vehicle body of a vehicle and will be connected to ground potential.

According to the present embodiment, the following operations and effects are achieved.
Since the relay ground terminal 33 connected to the ground of the vehicle is connected to the heat dissipation member 20 and the case 25 by the first connection portion 40 and the second connection portion 42, both the heat dissipation member 20 and the case 25 are electrically connected to the vehicle ground. Connection can be made. Therefore, the configuration of the electrical junction box 10 can be simplified as compared with the case where the case 25 and the heat dissipation member 20 are individually connected to the ground.

Further, the case 25 is provided with a shield connection portion 30 protruding outward, and the second connection portion 42 is connected to the shield connection portion 30.
The case 25 of the electrical connection box 10 is connected to the ground potential with a simple configuration by connecting the shield connection portion 30 protruding outward to the second connection portion 42 as in this configuration. Is possible.

Furthermore, the heat radiating member 20 is formed by extrusion molding, and the first connecting portion 40 is connected to the surface of the heat radiating member 20 on the circuit portion 11 side.
When the heat radiating member 20 is formed by extrusion molding, it is not easy to process the shape such as projecting a portion connected to the first connecting portion 40. According to this configuration, even if the heat dissipation member 20 is extruded, the first connection portion 40 of the relay ground terminal 33 and the surface of the heat dissipation member 20 on the circuit portion side are connected. It becomes possible to connect the heat dissipation member 20 to the ground potential.

Further, a frame-like member 45 is assembled on the heat radiating member 20 side, and an insertion hole 48 (insertion portion) through which the first connection portion 40 is inserted is formed in the frame-like member 45.
When the frame member 45 is assembled to the heat radiating member 20, it may be difficult to assemble the relay ground terminal 33 to the heat radiating member 20 because of the frame member 45. For example, even in the configuration having the frame-shaped member 45, the relay ground terminal 33 can be assembled by inserting the first connection portion 40 through the insertion hole 48.

  Further, since the relay ground terminal 33 is formed by bending a metal plate material, the configuration of the relay ground terminal 33 can be simplified.

<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 nut 44 is accommodated in the accommodation recess 57 to restrict the rotation of the nut 44. However, the present invention is not limited to this, and the nut 44 is fixed to the bottom surface of the second connection portion 42. May be. Various known means such as insert molding and welding can be used to fix the nut 44. Further, the shield connection part 30 and the second connection part 42 may be connected without using the nut 44. For example, the shield connection part 30 and the second connection part 42 may be screwed without using the nut 44 by performing burring on the periphery of the through hole.

DESCRIPTION OF SYMBOLS 10 ... Electrical junction box 11 ... Circuit part 12 ... Electronic component 20 ... Radiation member 21 ... Mounting surface 22, 23 ... Screw hole 25 ... Case 27 ... Side wall 28 ... Locking piece 29 ... Locking hole 30 ... Shield connection part 31 ... through hole 33 ... relay ground terminal 34 ... ground connection part 35 ... mounting hole 36 ... positioning hole 40 ... first connection part 41 ... through hole 42 ... second connection part 43 ... through hole 44 ... nut 45 ... frame-like member 48 ... insertion hole (insertion part)
49 ... Locking projection 52 ... Mounted portion 55 ... Positioning projection 56 ... Holding portion 57 ... Housing recess 59 ... Mounting hole

Claims (6)

An electrical junction box mounted on a vehicle,
A circuit part on which electronic components are mounted;
A conductive heat dissipating member that dissipates heat of the circuit portion;
A conductive case for accommodating the circuit portion with the heat dissipation member;
A relay ground terminal having a ground connection portion connected to the ground of the vehicle,
The relay ground terminal is an electrical connection box including a first connection portion connected to the heat dissipation member and a second connection portion connected to the case. The case is provided with a shield connecting portion protruding outward,
The electrical connection box according to claim 1, wherein the second connection portion is connected to the shield connection portion. The heat dissipation member is formed by extrusion molding,
The electrical connection box according to claim 1, wherein the first connection portion is connected to a surface of the heat dissipation member on the circuit portion side. The electrical connection box according to claim 3, wherein a frame-like member is assembled on the heat radiating member side, and an insertion portion through which the first connection portion is inserted is formed in the frame-like member. The frame-shaped member has an attached portion attached to the attachment portion of the vehicle,
The electrical connection box according to claim 4, wherein the ground connection portion is arranged on the attached portion. The electrical junction box according to any one of claims 1 to 5, wherein the relay ground terminal is formed by bending a metal plate material.

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