JP2007209047A - Manufacturing method of electrical junction box - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an electrical junction box excellent in a heat dissipation property. <P>SOLUTION: A filler 16 is filled, internally contacts a pair of heat dissipation planes 60 of a case 13, and raises a liquid level. There is no gap formed between the filler 16 and the heat dissipation planes 60 as the filler 16 is filled. After heat is generated from both front and back faces of a circuit component 12 and transmitted to the filler 16, heat is transmitted to both heat dissipation planes 60 of the case 13 through the filler 16 and externally dissipated from both heat dissipation planes 60. Since the gap is prevented from being formed between the filler 16 and the heat dissipation planes 60, the heat dissipation property of the electrical junction box 10 can be improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an electrical junction box.

Conventionally, the thing of patent document 1 is known as an electrical connection box which is mounted in a vehicle and controls the power interruption of an in-vehicle electrical component. This is a through-hole formed in the cover in a posture in which the plate surface of the circuit component is placed in a shallow dish-shaped case with the plate surface facing up and down, the case opening is closed with the cover, and the cover is on the upper side. Is manufactured by injecting a filler so as to fill the circuit structure (see FIG. 8 of Patent Document 1). Heat generated from the circuit structure is transmitted to the wall surfaces of the case and the cover through the filler, and is dissipated to the outside of the electrical junction box.
JP 2003-31979 A

  However, according to the above configuration, depending on the filling method, air may remain in the case, and there is a concern that a gap is formed between the wall surface of the cover and the filler. Then, due to the gap, heat generated from the upper surface of the plate surface of the circuit structure becomes difficult to be transmitted to the cover, and as a result, there is a concern that the heat dissipation property of the electrical junction box is lowered.

  This invention is completed based on the above situations, Comprising: It aims at providing the manufacturing method of the electrical junction box which has the outstanding heat dissipation.

  As means for achieving the above object, the invention of claim 1 is a pair of circuit components and a circuit for housing the circuit components and radiating heat from the circuit components to the outside on both sides of the circuit components. And a housing having a heat radiating surface, wherein the housing is filled with the filler so as to fill the circuit structure, and the filler is poured into the housing. When filling with, the housing has a vertical arrangement or an inclined arrangement so that the filling material raises the liquid level while being in contact with the inside of each heat radiation surface of the housing.

  According to a second aspect of the present invention, in the method according to the first aspect, the housing has a flat shape with a wide surface along the plate surface of the circuit component and a surface along the plate surface of the circuit component. It is characterized by comprising a case having different surfaces opened and a lid member that closes the opening of the case, and the filler is filled in a vertical arrangement with the lid member facing up.

  According to a third aspect of the present invention, in the method according to the first or second aspect, the circuit structure includes a circuit board and a bus bar attached to the circuit board, and the bus bar is arranged from a side edge of the circuit board. And the filling material is filled until the whole of the circuit board is filled, leaving the extending portion of the bus bar.

<Invention of Claim 1>
According to the first aspect of the present invention, the filler is filled so as to raise the liquid level while being in contact with the inside of the pair of heat radiation surfaces of the housing. Thereby, a gap is not formed between the heat radiation surface of the housing and the filler in a state where the filler is filled. As a result, the heat generated from both the front and back sides of the circuit structure is transferred to the filler, then transmitted through the filler to both heat radiating surfaces of the housing, and dissipated from both heat radiating surfaces to the outside of the housing. Is done. Thus, according to the invention of claim 1, since it is possible to prevent a gap from being formed between the filler and the heat radiating surface, an electrical junction box having excellent heat dissipation can be manufactured.

<Invention of Claim 2>
According to invention of Claim 2, it becomes possible to make the surface which makes | forms a wide flat shape along the plate | board surface of a circuit structure among housings into a heat radiating surface, From this heat radiating surface, Can be diffused to the outside, so that the heat dissipation of the electrical junction box can be further improved.

<Invention of Claim 3>
According to the invention of claim 3, since the extended portion of the bus bar is not embedded in the filler, the extended portion can be used for connection between the circuit structure and the external circuit.

  An embodiment in which the present invention is applied to an electric junction box 10 for a vehicle will be described with reference to FIGS. This device is connected between a power source (not shown) such as a battery and on-vehicle electrical components (not shown) such as a headlamp and a wiper, and performs on / off control of various on-vehicle electrical components. ing. The electrical junction box 10 is configured by housing a circuit component 12 in a flat housing 11. The housing 11 includes a case 13 having an opening and a flat shape, and a connector housing (corresponding to a lid member according to the present invention) 15 that closes the opening and includes a hood portion 14. The case 13 is filled with a filler 16 so as to fill the circuit component 12. Further, a cover 17 that covers the hood portion 14 of the connector housing 15 is attached to the housing 11. The electrical junction box 10 can be attached to the vehicle (not shown) in an arbitrary posture. For example, as shown in FIG. 1, the cover 17 can be attached to the vehicle with the posture directed downward.

(Case)
The case 13 is made of a synthetic resin and has a flat shape and opens downward. A stepped portion 20 is formed at the lower end of the case 13 so as to extend outward in the left-right direction in FIG. A lock claw 21 protruding outward is formed on the outer surface of the stepped portion 20, and the case 13 and the cover 17 are assembled by elastically engaging a lock claw receiving portion 22 of the cover 17 described later. It is supposed to be. The right end portion in FIG. 2 of the stepped portion 20 is formed to hang downward, and serves as a wire guide portion 23 for guiding a wire (not shown) when the cover 17 is assembled.

  As shown in FIG. 2, a plurality of elastic lock pieces 25 that can be bent and deformed outward are formed at the lower end portion of the stepped portion 20 of the case 13 by forming a slit 24 upward from the opening edge of the case 13. Has been. The elastic lock piece 25 is provided with a lock recess 26 penetrating in the thickness direction of the elastic lock piece 25, and is engaged with a lock projection 27 of the connector housing 15 to be described later. The housing 15 can be assembled.

  In the case 13, a pair of surfaces along the plate surface of the circuit component 12 are formed in a wide and flat shape above the stepped portion 20, and heat generated from the circuit component 12 is transmitted to the outside. The heat radiating surface 60 is used to dissipate.

(cover)
The cover 17 is made of a synthetic resin, and has an opening on the upper side and a shape that covers the lower end of the case 13 from below. A lower edge portion of the cover 17 is formed to be inclined downward toward the right side in FIG. 2, and an electric wire outlet port through which an unillustrated electric wire is led out at the right end portion in FIG. 2 among the lower end portions of the cover 17. 28 is formed (see FIG. 1), and the electric wire is led out through a space between the case 13 and the electric wire guide portion 23. . A lock claw receiving portion 22 that engages with the lock claw 21 of the case 13 described above is formed at the upper end portion of the cover 17, and the lock claw receiving portion 22 and the lock claw 21 are elastically engaged. Thus, the case 13 and the cover 17 are assembled.

(Connector housing)
The connector housing 15 is made of synthetic resin, and as shown in FIG. 6, a main body portion 30 having a substantially rectangular parallelepiped shape, and extending upward from the left and right end portions of the main body portion 30 in FIG. 12 and a pair of guide rails 31 for guiding the circuit component 12 when the connector housing 15 is assembled.

  On the outer surface of the end portion 30, a lock projection 27 that engages with the lock recess 26 provided in the elastic lock piece 25 of the case 13 described above is projected outward.

  As shown in FIG. 3, a plurality of hood portions 14 opening downward are formed on the lower surface of the main body portion 30, and can be fitted to a mating connector (not shown). An electric wire (not shown) is connected to the mating connector, and this electric wire is guided by the electric wire guide portion 23 of the case 13 and electrically connected between the electric wire guide portion 23 of the cover 17 and the electric wire outlet port 28. It is led out of the box 10.

  As shown in FIGS. 14, 16, and 17, a recess 61 is formed in the back wall of the hood portion 14. An insertion hole 34 is formed in the bottom wall of the recess 61 so as to penetrate in an up-down direction through which an extension 33 of the bus bar 32 of the circuit structure 12 to be described later passes. The insertion hole 34 also serves as an escape hole for the air in the case 13 to escape when the filler 16 is filled into the case 13.

  As will be described in detail later, when the filler 16 is filled into the case 13 to a predetermined liquid level, the filler 16 overflows into the recess 61 from the insertion hole 34, and thereby the filler 16. Can be confirmed to be filled to a predetermined liquid level. Since the filler 16 overflowing from the insertion hole 34 is accommodated in the recess 61 so as not to overflow into the hood portion 14, the filler 16 is interposed on the mating surface with the mating connector. It is possible to prevent the occurrence of poor fitting.

  A receiving plate portion 35 is formed on the upper surface side of the main body portion 30 and extends upward from the right edge of the insertion hole 34 in FIG. 4 and receives the extended portion 33 of the bus bar 32 from the right side in FIG. 4. As shown in FIG. 6, the receiving plate part 35 is formed over substantially the entire width in the left-right direction of the main body part 30 in FIG.

  A rib 43 that protrudes leftward and extends upward is formed from the left side surface of the receiving plate portion 35 in FIGS. 3 and 4. The rib 43 is formed between the adjacent insertion holes 34 and enters between the adjacent extending portions 33. The rib 43 is crushed from the left side in FIG. 4 by being heated and pressurized in a state where the extending portion 33 is inserted into the insertion hole 34, and is in close contact with the extending portion 33 and between the receiving plate portion 35 and the rib 43. By holding the extension part 33, the extension part 33 is prevented from coming off.

  On the upper surface of the main body portion 30, at positions near the left and right ends in FIG. 8, the region surrounded by the pair of slits 24 provided downward from the upper edge of the receiving plate portion 35 is directed upward. A pair of elastic engagement portions 36 extending is formed. The elastic engagement portion 36 is elastically deformable in the left-right direction in FIG. At the upper end portion of the elastic engagement portion 36, an engagement protrusion 37 is formed so as to protrude to the left in FIG. 7 and can be engaged with the engagement hole 38 of the circuit component 12.

  The guide rail 31 is substantially U-shaped when viewed from above, and both left and right ends of the circuit component 12 are inserted into a space surrounded by the U-shape to guide the circuit component 12 in the vertical direction. It is possible.

  An inlet 18 for injecting the filler 16 into the case 13 is formed at the right end of the main body 30 in FIG. As shown in FIGS. 10 and 15, an injection tube portion 19 is formed in communication with the injection port 18. As shown in FIGS. 9 to 10, the filler 16 is injected into the case 13 with the injection port 18 facing upward, and the injection cylinder portion 19 faces downward in FIG. The lower end edge in FIG. 10 of the injection cylinder part 19 is formed extending to the vicinity of the lower wall in FIG.

(Circuit structure)
As shown in FIG. 5, the circuit component 12 has an electronic component 40 mounted on a conductive path (not shown) formed by, for example, a printed wiring technique on the surface of a circuit board 39, and a plurality of bus bars 32 on the back surface. It is bonded through an insulating adhesive layer (not shown). An opening 41 is formed in the circuit board 39, and the bus bar 32 is exposed in the opening 41. An electronic component 40 is accommodated in the opening. A connection terminal (not shown) is provided on the surface of the electronic component 40 on the bus bar 32 side, and the connection terminal and the bus bar 32 are connected to each other. It is like that. In addition, a plurality of connection terminals 42 are formed on the lower surface side in FIG. 7 of the electronic component 40, extending downward and then bent substantially at right angles to the circuit board 39 side. As shown in FIG. 7, a part of the connection terminals 42 provided on each electronic component 40 is connected to the bus bar 32 exposed from the opening, and the other connection terminals 42 are conductive conductors formed on the surface of the circuit board 39. Connected to the road.

  As shown in FIG. 4, the bus bar 32 extends downward from the lower end edge of the circuit board 39 to form an extension portion 33. As shown in FIGS. 3 and 4, the lower portion of the extension portion 33 is inserted into an insertion hole 34 formed in the back wall of the hood portion 14 of the connector housing 15 and protrudes into the hood portion 14. It can be mated with the mating connector. The outer surface of the extending portion 33 is in contact with the insertion hole 34.

  As shown in FIGS. 6 and 8, both the circuit board 39 and the bus bar 32 are engaged with an elastic engagement portion 36 to be described later in a state where the circuit component 12 is held in a normal position with respect to the connector housing 15. An engagement hole 38 is formed at a position corresponding to the mating protrusion 37. As shown in FIG. 7, the engagement protrusions 37 are engaged with the engagement holes 38, so that the circuit component 12 is prevented from coming off upward in FIG. The circuit board 39 is fixed to the connector housing 15 by engaging with an elastic engagement portion 36 formed integrally with the connector housing 15.

  As shown in FIG. 5, an engagement recess 44 is formed in a surface of the extension 33 that is close to the circuit board 39, on the surfaces of the extension 33 that are adjacent to each other. As shown in FIG. 6, when the rib 43 is crushed, the rib 43 bulges into the engagement recess 44, and the rib 43 and the engagement recess 44 engage to prevent the extension 33 from coming off. It is supposed to be.

  As shown in FIGS. 3, 4, and 18, the case 13 is filled with a filler 16 that fills the entire circuit board 39 while leaving the extending portion 33. As shown in FIGS. 10 and 18, the filler 16 is filled in the case 13 with the case 13 facing downward and the connector housing 15 facing upward. The entire circuit board 39 is filled with the filler 16 so that the circuit structure 12 is waterproofed. Further, the heat generated from the electronic component 40 and the bus bar 32 of the circuit structure 12 is transmitted to the filler 16, is transmitted through the filler 16, and is dissipated to the outside from the heat radiation surface 60 of the case 13. It has become.

  The present embodiment has the above structure, and the manufacturing method thereof will be described. First, the circuit structure 12 is assembled to the connector housing 15. As shown in FIG. 11, both end edges of the circuit board 39 of the circuit component 12 are inserted into the guide rail 31 of the connector housing 15. As shown in FIG. 12, when the assembly process proceeds and the tip of the extending portion 33 reaches the receiving plate portion 35, the circuit component 12 is further moved while the extending portion 33 and the receiving plate portion 35 are in sliding contact. insert. Then, the extension portion 33 is inserted into the insertion hole 34 while being guided by the receiving plate portion 35. As the assembly proceeds, the elastic engagement portion 36 of the connector housing 15 comes into contact with the bus bar 32 and is elastically bent and deformed to the back side of the circuit board 39.

  As shown in FIG. 13, in a state where the circuit component 12 is assembled at the normal position with respect to the connector housing 15, the elastic engagement portion 36 is restored and deformed, and the engagement protrusion 37 of the elastic engagement portion 36 is a circuit. The structure 12 is engaged with the engagement hole 38 of the structure 12. At this time, since the extension portion 33 is in contact with the insertion hole 34, the extension portion 33 is supported by the inner wall surface of the insertion hole 34, so that the circuit component 12 is bent and deformed in a direction to escape from the elastic engagement portion 36. Can be prevented. As a result, the circuit component 12 is fixed to the connector housing 15 by the elastic engagement portion 36 formed integrally with the connector housing 15.

  Subsequently, the ribs 43 are heated and melted and crushed. Then, the rib 43 is in close contact with the extending portion 33. The extending portion 33 is sandwiched between the rib 43 and the receiving plate portion 35. Furthermore, the rib 43 comes into contact with and engages by expanding into an engagement recess 44 formed in the extension portion 33. Thereby, the bus bar 32 is fixed to the connector housing 15.

  Thereafter, the connector housing 15 assembled with the circuit structure 12 is accommodated in the case 13. Then, the lock protrusion 27 of the connector housing 15 and the elastic lock piece 25 of the case 13 come into contact with each other, the elastic lock piece 25 is elastically deformed and then restored and deformed, and the lock protrusion 27 is inside the lock recess 26 of the elastic lock piece 25. The connector housing 15 and the case 13 are assembled by engaging with.

  Now, in a state where the connector housing 15 and the case 13 are assembled, in a vertical posture with the case 13 facing downward and the connector housing 15 facing upward (see FIG. 10), liquid is supplied from the inlet 18 of the connector housing 15. The filler 16 is injected. The filler 16 flows down from the injection port 18 into the injection cylinder portion 19 and is injected into the case 13 through an opening formed in the vicinity of the lower wall of the case 13 in FIG.

  First, the filler 16 spreads on the inner surface of the lower wall of the case 13 in FIG. 10, and the inner surface of the lower wall of the case 13 is covered with the filler 16. When the filler 16 is further injected, the liquid level of the filler 16 rises while contacting the inner surface of the side wall of the case 13. Thereby, a gap is not formed between the filler 16 and the inner surface of the heat radiation surface 60 of the case 13. The air in the case 13 is pushed by the filler 16 and escapes upward from the insertion hole 34 of the connector housing 15. Thereby, the filler 16 can be smoothly injected into the case 13.

  When the filler 16 is further injected, the entire circuit board 39 is buried in the filler 16 except for the extending portion 33. Thereby, waterproofing and insulation of the circuit structure 12 can be achieved. When the liquid level of the filler 16 reaches the insertion hole 34 of the connector housing 15, the filler 16 overflows into the recess 61 from the insertion hole 34. Thereby, it can be confirmed visually that the filler 16 is filled in the case 13 by a normal amount. When the filler 16 overflows from the insertion hole 34 in this way, the injection of the filler 16 is terminated (see FIG. 18). 2 and 3, the inside of the recess 61 is filled with the filler 16, but if the filler 16 overflows into the recess 61 from the insertion hole 34, The entire recess 61 may not be filled with the filler 16.

  In a state where the case 16 is filled with the regular amount of the filler 16, no gap is formed between the heat radiation surface 60 of the case 13 and the filler 16 as described above. As a result, the heat generated from the front and back surfaces of the circuit component 12 is transmitted to the filler 16, then transmitted through the filler 16 to both the heat radiating surfaces 60 of the case 13, and from both the heat radiating surfaces 60. Dissipated outside. As described above, according to the present embodiment, it is possible to prevent a gap from being formed between the filler 16 and the heat dissipation surface 60, so that the heat dissipation of the electrical junction box 10 can be improved.

  When the filler 16 is filled into the case 13 by a normal amount, the filler 16 is solidified. Thereafter, the mating connector is fitted into the hood portion 14. The mating connector is electrically connected to the circuit component 12 by connecting to the extending portion 33 protruding into the hood portion 14. A cover 17 is assembled from the side of the connector housing 15 where the hood portion 14 is formed. Then, the lock claw 21 of the case 13 and the lock claw receiving portion 22 of the cover 17 come into contact with each other, and after the lock claw 21 is elastically deformed, the lock claw 21 is restored and deformed, and the lock claw 21 and the lock claw receiving portion 22 are elastically engaged. By combining, the cover 17 and the connector housing 15 are assembled. The electric wire connected to the mating connector is led out between the electric wire guide portion 23 of the connector housing 15 and the electric wire outlet port 28 of the cover 17, and the other end of the electric wire is connected to an external circuit (not shown).

  As described above, according to the present embodiment, the filling material 16 is filled so as to raise the liquid level while being in contact with the inside of the pair of heat radiation surfaces 60 of the case 13. No gap is formed between 60 and the filler 16. As a result, the heat generated from the circuit component 12 is transmitted to the heat radiating surface 60 of the case 13 through the filler 16 without being hindered by the gap, and thus the electrical junction box 10 having excellent heat dissipation is manufactured. Can do.

  Furthermore, it becomes possible to make the surface which makes a wide flat shape along the plate | board surface of the circuit structure body 12 among the case 13 into the heat radiating surface 60, and heat generated from the circuit structure body 12 from this heat radiating surface 60 is externally supplied. Therefore, the heat dissipation of the electrical junction box 10 can be further improved.

  Further, since the extended portion 33 of the bus bar 32 is not embedded in the filler 16, the circuit component 12 and the external circuit are electrically connected by connecting the extended portion 16 and the mating connector. Can be connected to.

<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 present embodiment, the housing 11 is arranged vertically, and the filler 16 is filled in the housing 11. However, the present invention is not limited to this, and the liquid level is raised while the filler 16 is in contact with the inside of each heat radiation surface 60. If possible, the filling material 16 may be filled into the housing 11 with the housing 16 in an inclined arrangement.

  (2) The housing 11 is composed of a case 13 in which one of the surfaces of the housing 11 along the plate surface of the circuit component 12 is opened, and a lid member that closes the opening. After the body 12 is accommodated, the lid member may be attached to the case 13, and in this state, the housing 11 may be filled in the housing 11 with the vertical arrangement or the inclined arrangement.

  (3) In the circuit structure 12, for example, a bus bar is attached to a connection end of a conductive path formed on the circuit board 39 by a printed wiring technique, and the bus bar extends from a side edge of the circuit board 39. The filler may be filled until the entire circuit board 39 is filled, leaving the extended portion of the bus bar.

  (4) As the filler 16, any material can be used as long as it can transfer heat generated from the circuit component 12, such as an epoxy resin, a urethane resin, or a silicone resin.

The perspective view of the electrical junction box concerning one embodiment of the present invention. Front view of electrical junction box AA line sectional view in FIG. BB sectional view in FIG. The perspective view which shows the circuit structure 12 Front view showing a state where the connector housing and the circuit structure are assembled. CC sectional view in FIG. Rear view showing the connector housing and circuit component assembled Side view showing the connector housing and case assembled EE sectional view in FIG. The perspective view which shows the state before attaching a connector housing and a circuit structure. The perspective view which shows the middle state of the assembly | attachment operation | work of a connector housing and a circuit structure The perspective view which shows the state which assembled | attached the connector housing and the circuit structure. Bottom view showing the connector housing and case assembled FF sectional view taken on the line in FIG. GG sectional view in FIG. HH sectional view taken on the line in FIG. 9 is a cross-sectional view taken along line EE in FIG. 9, showing a state after filling the case with a filler.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Electrical junction box 11 ... Housing 12 ... Circuit structure 13 ... Case 15 ... Connector housing (lid member)
16 ... Filler 32 ... Bus bar 33 ... Extension part 39 ... Circuit board 60 ... Heat dissipation surface

Claims (3)

A circuit structure, and a housing that houses the circuit structure and has a pair of heat radiation surfaces that dissipate heat from the circuit structure to the outside on both front and back sides of the circuit structure. A method of manufacturing an electrical junction box filled with a filler so as to fill a component,
When the filling material is poured into the housing and filled, the housing is arranged vertically or inclined so that the filling material raises the liquid level while being in contact with the inside of each heat radiation surface of the housing. A method for manufacturing an electrical junction box. The housing has a flat shape with a wide surface along the plate surface of the circuit structure, and a case in which a surface different from the surface along the plate surface of the circuit structure is opened, and the opening of the case is blocked. The method for manufacturing an electrical junction box according to claim 1, further comprising a lid member, wherein the filler is filled in a vertical arrangement with the lid member facing up. The circuit structure includes a circuit board and a bus bar attached to the circuit board, and the bus bar includes an extending portion extending side by side from a side edge of the circuit board, and the filler is used as the bus bar. 3. The method of manufacturing an electrical junction box according to claim 1, wherein filling is performed until the whole of the circuit board is filled, leaving an extended portion of the electrical connection box.

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