JP2010172121A - Circuit structure and electrical junction box - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit structure that achieves miniaturization, and an electrical junction box. <P>SOLUTION: The circuit structure 30 includes a base substrate 32 having a circuit pattern 31 composed of a plurality of conductive members 41A, 41B, and an electronic component 33 mounted on the surface or the backside of the base substrate 32. The base substrate 32 is formed by assembling a circuit unit 40, in which the conductive members 41A, 41B are arranged while being superposed on each other and an insulating part 42 is formed therebetween by molding, to a circuit board 50. By such a configuration, an area of the base substrate 32 is reduced as compared with the case of arranging all the conductive members 41A, 41B in a surface direction, thereby achieving the miniaturization of the circuit structure 30. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a circuit structure and an electrical junction box.

  2. Description of the Related Art Conventionally, there has been known a circuit structure having a circuit pattern composed of a plurality of conductive members and having electronic components mounted on the front surface or the back surface (for example, Patent Document 1). This circuit structure is formed by molding a metal plate material punched into a predetermined shape with an insulating material.

JP 2006-24620 A

By the way, when the circuit structure is accommodated in the case and stored in the engine room of the vehicle, the space in the engine room is limited. Therefore, it is important to make the circuit structure as small as possible. is there. However, the circuit structure having the above-described configuration has a problem that since all the conductive members constituting the circuit pattern are arranged in the plane direction, the area becomes large and it is difficult to reduce the size.
The present invention has been completed based on the above circumstances, and an object thereof is to provide a circuit structure and an electrical junction box that can be reduced in size.

  The circuit structure of the present invention is a circuit structure including a base substrate having a circuit pattern composed of a plurality of conductive members, and an electronic component mounted on the front surface or the back surface of the base substrate. The substrate is formed by assembling a circuit unit in which the conductive member is placed on the front and back and an insulating portion is molded between the conductive members. According to such a configuration, since the area of the base substrate is smaller than arranging all the conductive members in the plane direction, the circuit structure can be reduced in size.

  In addition, the component connection portion to which the terminal portion of the electronic component is connected in the circuit unit is the component connection portion of one conductive member among the conductive members arranged on the front and back sides of the other conductive member. The component connecting portion may be provided so as to protrude toward the component connecting portion, and the component connecting portion of the circuit unit may be fitted to a fitting portion formed on the circuit board. According to such a configuration, the step between the component connecting portion of the circuit unit and the front or back surface of the circuit board can be reduced, and accordingly, the electronic component connected to both the circuit unit and the circuit board. Thus, the length of the terminal portion can be reduced, and the electronic component can be miniaturized.

  A gap may be provided at least between the fitting portion and the component connecting portion. Here, the component connection part of the circuit unit is a part to which heat of the electronic component is directly transmitted, and a gap is provided between the part and the fitting part, so that the heat from the electronic component is It becomes difficult to transmit to the circuit board side. This is advantageous when an electronic component having low heat resistance is mounted on the circuit board.

  The circuit unit is configured such that the component connection portion protrudes from a plate portion arranged along the front surface or the back surface of the circuit board, and a gap is provided between the plate portion and the circuit board. It is good as it is. According to such a configuration, it becomes difficult for the heat of the circuit unit to be transmitted from the plate portion to the circuit board side. This is more advantageous when an electronic component having low heat resistance is mounted on the circuit board.

  Further, at least the fitting portion and the component connecting portion may be provided in a continuous manner. Here, the component connection part of the circuit unit is a part that directly transfers the heat of the electronic component, and the heat from the electronic component is transferred to the circuit by providing such a part and the fitting part in a row. It becomes easy to transmit to the substrate side. Thereby, the heat of the electronic component is dispersed and dissipated to the circuit board side, so that the heat dissipation efficiency can be improved.

Further, the circuit unit has a configuration in which the component connecting portion protrudes from a plate portion arranged along the front surface or the back surface of the circuit board, and the plate portion and the circuit board are provided in a row. It may be a thing. According to such a configuration, the heat of the circuit unit is easily transferred from the plate portion to the circuit board side. Thereby, the improvement of the further heat dissipation efficiency can be aimed at.
The electrical junction box of the present invention is configured by housing the circuit structure in a case.

  ADVANTAGE OF THE INVENTION According to this invention, the circuit structure body and electrical junction box which can achieve size reduction can be provided.

1 is an external perspective view of an electrical junction box according to Embodiment 1. FIG. Exploded perspective view Same surface AA sectional view of FIG. BB sectional view of FIG. External perspective view of base substrate Same surface CC sectional view of FIG. DD sectional view of FIG. Exploded perspective view of base substrate Exploded perspective view of circuit unit Sectional drawing of the electrical-connection box concerning Embodiment 2. Cross section of base substrate The perspective view showing the state before setting a circuit unit to a lower model The perspective view showing the state which set the circuit unit to the lower model The perspective view showing the state before setting a circuit board in a lower mold A perspective view showing a state where the circuit board is set in the lower mold A perspective view showing a state in which the upper mold and the lower mold are closed Perspective view of the base substrate from the back side

<Embodiment 1>
Hereinafter, Embodiment 1 which actualized this invention is demonstrated in detail, referring FIGS. 1-11.
The electrical connection box 10 in the present embodiment 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 disconnects various on-vehicle electrical components. Electric control is performed. Hereinafter, in each component member, the upper side in FIG. 2 will be described as the front side, the lower side as the back side, the left front side as the lower side, and the right back side as the upper side.

The electrical junction box 10 is configured by housing a circuit structure 30 in a case 20.
The case 20 is made of synthetic resin, has a flat shape as a whole, and has a first case 20A assembled from the back side to the circuit structure 30 and a second case 20B assembled from the front side. The first case 20A has a shallow dish shape that opens outward, and the second case 20B has a form that closes the opening of the first case 20A. The circuit component 30 is fixed to the first case 20A by screws (not shown), and the first case 20A and the second case 20B are joined by ultrasonic welding.

  In the second case 20B, a connector fitting portion 21 that can be fitted with a mating connector connected to a power source or a vehicle-mounted electrical component via an electric wire (not shown) is formed to open downward. The second case 20B is integrally provided with a plurality of terminal fittings 22 by insert molding (see FIGS. 4 and 5). Each terminal fitting 22 has a shape bent in an L shape, and one end side thereof is arranged to project downward in the connector fitting portion 21 and is electrically connected to the mating connector. The other end of the terminal fitting 22 protrudes into the case 20 and is electrically connected to the circuit component 30.

  The circuit structure 30 includes a base substrate 32 having a circuit pattern 31 composed of a plurality of conductive members 41, and an electronic component such as a semiconductor switching element 33 is mounted on the surface of the base substrate 32.

  The semiconductor switching element 33 includes a main body 33A, a drain terminal (power terminal) (not shown) provided on the back surface of the main body 33A, and a gate terminal 33B (control terminal) provided so as to protrude from the side surface of the main body 33A. And a source terminal 33C (power terminal). Note that the drain terminal and the source terminal 33C correspond to the terminal portions of the electronic component of the present invention. Each terminal of the semiconductor switching element 33 is connected to the base substrate 32 by a known method such as soldering.

  As shown in FIG. 6, the base substrate 32 is formed by assembling a circuit unit 40 having a circuit pattern 31 composed of a plurality of conductive members 41 to a circuit substrate 50.

  The circuit unit 40 is formed by placing conductive members 41 on the front and back and molding an insulating portion 42 therebetween. One of the conductive members 41 arranged so as to overlap the front and back constitutes an input circuit to which power from a power source is supplied, and the other constitutes an output circuit that outputs the power to the outside. The conductive member 41 constituting the input circuit is referred to as a first conductive member 41A, and the conductive member 41 constituting the output circuit is referred to as a second conductive member 41B.

  The circuit unit 40 includes a plate portion 43 having a flat plate shape and a component connecting portion 34 provided so as to protrude from the plate portion 43 in the plate thickness direction (see FIGS. 8 and 9). The plate portion 43 is disposed along the back surface of the circuit board 50, and the component connection portion 34 is connected to the drain terminal and the source terminal 33 </ b> C of the semiconductor switching element 33. The component connection part 34 includes a first component connection part 44 to which the drain terminal of the semiconductor switching element 33 in the first conductive member 41A is electrically connected, and a source terminal 33C of the semiconductor switching element 33 in the second conductive member 41B. The second component connecting portion 45 is electrically connected.

  The first conductive member 41A is made of metal and processed into a substantially rectangular plate shape as a whole (see FIG. 11). The first conductive member 41 </ b> A includes a plate portion 43 and a first component connection portion 44.

  The first component connecting portion 44 is provided so as to protrude from the plate portion 43 to the front side, and extends linearly from one end to the other end of the plate portion 43 in the longitudinal direction. The projecting dimension of the first component connecting part 44 from the plate part 43 is equivalent to the thickness of the circuit board 50 and is constant throughout (see FIGS. 8 and 9). The first component connecting portion 44 is provided at an intermediate portion of the plate portion 43 in the short direction (vertical direction).

  The plate portion 43 has a thin plate shape with a constant thickness dimension as a whole. The second conductive member 41 </ b> B is disposed so as to overlap the portion of the plate portion 43 above the first component connection portion 44. A plurality of first through holes 46A having a long oval shape along the longitudinal direction of the plate portion 43 are formed in a portion of the plate portion 43 where the second conductive member 41B is arranged to overlap (see FIG. 11). ). The peripheral surface of each first through hole 46A is covered with an insulating portion 42 (see FIG. 8).

  A plurality of terminal connection holes 47 to which the other end side of the terminal fitting 22 is electrically connected are provided on the outer side of the portion of the plate portion 43 where the second conductive member 41B is placed so as to overlap. Each terminal connection hole 47 has a substantially circular shape and penetrates the plate portion 43 in the front and back direction. The terminal connection hole 47 is formed at a position slightly above the first through hole 46A and is disposed along the upper edge of the plate portion 43. The other end side of the plurality of terminal fittings 22 among all the terminal fittings 22 is inserted into a terminal connection hole 47 from a terminal insertion hole 51 of a circuit board 50 described later, and is electrically connected to the terminal connection hole 47 by soldering or the like. (See FIG. 5).

  The plate portion 43 is provided with a unit fixing hole 48 for fixing the circuit unit 40 to the circuit board 50 (see FIG. 10). The unit fixing hole 48 has a substantially circular shape and penetrates the plate portion 43 in the front and back direction. A plurality of unit fixing holes 48 are provided side by side along the upper and lower edges of the plate portion 43 at a predetermined interval.

  The second conductive member 41B is formed in a predetermined shape by pressing a metal plate material. The plate thickness dimension of the second conductive member 41B is thinner than the plate thickness dimension of the circuit board 50, and is substantially equal in all the second conductive members 41B.

  A plurality (five in this embodiment) of second conductive members 41B are arranged side by side with respect to one first conductive member 41A. The plurality of second conductive members 41B are arranged along the length direction of the first component connecting portion 44 of the first conductive member 41A at a predetermined interval.

  A lower edge portion (a portion disposed along the first component connection portion 44) of the second conductive member 41 </ b> B is a second component connection portion 45. The dimension obtained by adding the thickness dimension of the second conductive member 41B and the insulating part 42 is equivalent to the protruding dimension from the plate part 43 of the first component connecting part 44. As shown in FIGS. The protruding end surface (front surface) of the first component connection portion 44 and the surface of the second component connection portion 45 (surface of the second conductive member 41B) have the same height (position in the thickness direction of the circuit unit 40). ing. And the protrusion end surface of the 1st component connection part 44, the surface of the insulation part 42, and the surface of the 2nd component connection part 45 comprise the flat surface.

  A second through hole 49 that is substantially circular and penetrates the second conductive member 41B in the front and back direction is provided at the upper edge of each second conductive member 41B. The second through holes 49 are arranged along the upper edge of each second conductive member 41B, and the second through holes 49 provided in some second conductive members 41B among all the second conductive members 41B are: It is connected to the first through hole 46A of the first conductive member 41A in the front and back direction, and is exposed to the back surface of the circuit unit 40 through the first through hole 46A. In addition, the second through hole 49 provided in the other second conductive member 41B among all the second conductive members 41B has a circuit via a notch 46B formed in the upper corner of the first conductive member 41A. It is exposed on the back surface of the unit 40. The other end side of the plurality of terminal fittings 22 among all the terminal fittings 22 is inserted into the second through hole 49 and electrically connected by soldering or the like (see FIG. 4).

  As shown in FIG. 10, the insulating part 42 includes a first insulating part 42A that insulates between the plate part 43 of the first conductive member 41A and the second conductive member 41B, and a first component connection of the first conductive member 41A. A second insulating portion 42B that insulates between the portion 44 and the second component connecting portion 45 of the second conductive member 41B, and a third insulating portion 42C that insulates between the adjacent second conductive members 41B. Yes. In addition, the part located in the back side of the 2nd through-hole 49 among the insulation parts 42 is opened in the front and back direction.

  The circuit unit 40 is manufactured as follows, for example. First, the first conductive member 41A is formed by forging, rolling, pressing or cutting the metal material, and the second conductive member 41B is formed by pressing the metal plate into a predetermined shape. Next, the first conductive member 41A and the second conductive member 41B are set in a molding die (not shown), and the insulating portion 42 is molded.

The circuit board 50 has a substantially rectangular shape that can be accommodated in the case 20. Conductive paths (not shown) are formed on the surface of the circuit board 50 by printed wiring means.
The circuit board 50 is provided with a plurality of terminal insertion holes 51 through which the other end of the terminal fitting 22 can be inserted. The terminal insertion hole 51 is formed in a portion located on the front side of the terminal connection hole 47 of the circuit unit 40, has a substantially oval shape that is long along the longitudinal direction of the circuit board 50, and the circuit board 50 faces in the front-back direction (thickness direction). ). The terminal connection hole 47 is exposed to the front side of the base substrate 32 through the terminal insertion hole 51 (see FIG. 7).

  The circuit board 50 is formed with a fitting portion 52 into which the component connecting portion 34 (portion excluding the plate portion 43) of the circuit unit 40 can be fitted. The fitting portion 52 is formed at the upper corner portion of the circuit board 50 and has a shape along the outer shape of the first component connection portion 44 and the second conductive member 41B of the circuit unit 40 and opens in the front and back direction of the circuit board 50. ing. The component connection part 34 of the circuit unit 40 is fitted into the fitting part 52 and exposed to the front side of the circuit board 50. The surface of the component connecting portion 34 of the circuit unit 40 and the surface of the circuit board 50 are aligned in height (position in the thickness direction of the circuit board 50), and the surface of the base board 32 is a flat surface. . And the gate terminal 33B of the semiconductor switching element 33 is connected to the peripheral part (part along a lower edge) of the fitting part 52 among the circuit boards 50. FIG.

  A board fixing hole 53 is provided at a position in the circuit board 50 that is aligned with the unit fixing hole 48 of the circuit unit 40 at the peripheral edge of the fitting part 52. Each board fixing hole 53 has a circular shape that is substantially the same shape and size as the unit fixing hole 48 and penetrates the circuit board 50 in the front and back direction.

  A resin-made fixing pin 35 is press-fitted into the substrate fixing hole 53 and the unit fixing hole 48 that are continuous in the front and back direction. The fixing pin 35 is inserted into the unit fixing hole 48 from the substrate fixing hole 53 and then crushed in the axial direction while being heated, and both ends in the axial direction are crushed flat. The plate portion 43 of the circuit unit 40 is fixed to the circuit board 50 by the fixing pins 35, and the circuit unit 40 and the circuit board 50 are integrally held.

  A gap is provided between the circuit unit 40 and the circuit board 50 (see FIGS. 8 and 9). Specifically, between the fitting part 52 of the circuit board 50 and the first component connecting part 44 and the second conductive member 41B of the circuit unit 40, and between the back surface of the circuit board 50 and the plate part 43 of the circuit unit 40. A predetermined gap is provided.

Next, operations and effects of the first embodiment configured as described above will be described.
The circuit configuration body 30 of the present embodiment is mounted on the surface of the base substrate 32 having the circuit pattern 31 configured by a plurality of conductive members 41 (first conductive member 41A and second conductive member 41B) and the base substrate 32. The base circuit board 32 includes a first conductive member 41A and a second conductive member 41B that are placed on the front and back, and an insulating portion therebetween. The circuit unit 40 formed by molding 42 is assembled to the circuit board 50. As a result, the area of the base substrate 32 can be reduced as compared with the case where all the conductive members 41 are arranged side by side in the plane direction, so that the circuit structure 30 can be downsized accordingly.

  In addition, the component connecting portion 34 to which the drain terminal and the source terminal 33C of the semiconductor switching element 33 in the circuit unit 40 are connected is the first of the first conductive member 41A and the second conductive member 41B that are arranged on the front and back. The first component connecting portion 44 of the conductive member 41A (one conductive member 41) is provided so as to protrude toward the second component connecting portion 45 side of the second conductive member 41B (the other conductive member 41). The component connection part 34 of the unit 40 is fitted in a fitting part 52 formed on the circuit board 50.

  Thereby, the level | step difference of the front-back direction between the component connection part 34 of the circuit unit 40 and the surface of the circuit board 50 can be made small. Here, when connecting the terminal parts of one electronic component to the first component connecting part and the second component connecting part of the circuit unit and the circuit board, respectively, the terminal parts are provided by the steps in the front and back direction between them. It is necessary to lengthen the length, and the larger the step, the larger the electronic component. However, in the circuit configuration body 30 of the present embodiment, the first component connection portion 44 of the first conductive member 41A, the second component connection portion 45 of the second conductive member 41B, and the circuit board 50, which are arranged on the front and back sides. Accordingly, the length of the source terminal 33C and the gate terminal 33B can be reduced accordingly, and the semiconductor switching element 33 can be downsized accordingly.

  Further, a gap is provided between the fitting portion 52 and the component connecting portion 34 in the circuit configuration body 30. Here, the component connection part 34 of the circuit unit 40 is a part that directly transfers the heat of the semiconductor switching element 33, and a gap is provided between such a part and the fitting part 52, so that the semiconductor It becomes difficult for the heat from the switching element 33 to be transmitted to the circuit board 50 side. This is advantageous when an electronic component having low heat resistance is mounted on the circuit board 50.

  Further, the circuit unit 40 has a configuration in which the component connecting portion 34 protrudes from the plate portion 43 disposed along the back surface of the circuit board 50, and the circuit unit 30 is provided between the plate portion 43 and the circuit board 50. Is provided with a gap. This makes it difficult for the heat of the circuit unit 40 to be transmitted from the plate portion 43 to the circuit board 50 side, which is more advantageous when an electronic component with low heat resistance is mounted on the circuit board 50.

  Further, the circuit unit 40 is held integrally with the circuit board 50 by fixing the plate portion 43 having a projected area on the circuit board 50 smaller than the area of the circuit board 50 to the circuit board 50. Here, the material constituting the circuit board 50 and the material constituting the plate portion 43 have different coefficients of thermal expansion. For example, when the plate portion is fixed over the entire surface of the circuit board, the plate portion and the circuit board There is a risk that stress applied to the fixed portion of the substrate increases, causing warpage of the base substrate and peeling of the plate portion. However, in the circuit configuration body 30 of the present embodiment, the plate portion 43 fixed to the circuit board 50 is much smaller than the area of the circuit board 50, so that the stress as described above is reduced. Warping of the base substrate 32, peeling of the plate portion 43, and the like can be prevented.

<Embodiment 2>
Next, an electrical junction box 10 according to a second embodiment of the present invention will be described with reference to FIGS.
The electrical junction box 10 of the present embodiment is different from the first embodiment in that no gap is provided between the circuit board 50 and the circuit unit 40 constituting the base substrate 32. In addition, the same code | symbol is attached | subjected to the structure similar to Embodiment 1, and the overlapping description is abbreviate | omitted.

  As in the first embodiment, the electrical junction box 10 according to the present embodiment accommodates a circuit component 30 in a case 20, and the circuit component 30 includes a circuit pattern 31 including a plurality of conductive members 41. The base substrate 32 is provided, and electronic components such as the semiconductor switching element 33 are mounted on the surface of the base substrate 32. The base substrate 32 is obtained by assembling the circuit unit 40 having the circuit pattern 31 to the circuit substrate 50 as in the first embodiment.

  There is no gap between the circuit unit 40 and the circuit board 50, and these are in close contact. Specifically, the fitting portion 52 of the circuit board 50 is in close contact with the first component connecting portion 44 and the second conductive member 41B, and the plate portion 43 and the back surface of the circuit board 50 are in close contact with each other.

  The circuit board 50 is provided with a positioning hole 63 for positioning the circuit board 50 with respect to a lower mold 70B described later (see FIG. 16). The positioning hole 63 is formed at the end of the circuit board 50 in the longitudinal direction on the side of the fitting portion 52. The positioning hole 63 is slightly larger than the board fixing hole 53 and has a circular shape into which a positioning boss 73 described later can be fitted and penetrates the circuit board 50 in the front and back direction.

  A portion of the circuit unit 40 corresponding to the positioning hole 63 of the circuit board 50 is formed with a substantially rectangular window portion 64. The window 64 is formed at one end in the longitudinal direction of the first conductive member 41A (the end opposite to the notch 46B). The positioning hole 63 of the circuit board 50 is exposed to the back side of the circuit board 50 through the window portion 64.

  The circuit unit 40 and the circuit board 50 are integrally formed by molding a resin-made fixing column 60 into the board fixing hole 53 of the circuit board 50 and the unit fixing hole 48 of the circuit unit 40 that are continuous in the front and back direction. Is retained. The fixing column 60 has a shaft portion (not shown) that penetrates the unit fixing hole 48 and the substrate fixing hole 53 and is in close contact with the peripheral surface of the hole, and a flange portion 62 that engages with the back surface of the circuit unit 40. However, the plate portion 43 of the circuit unit 40 is fixed to the circuit board 50 by the fixing column 60 (see FIG. 19).

Next, an example of the manufacturing process of the circuit structure 30 according to the present embodiment will be described.
In order to manufacture the circuit structure 30, the previously manufactured circuit unit 40 and the circuit board 50 are molded and integrated. The molding die 70 used at this time has the following shape.

The molding die 70 has an upper die 70A and a lower die 70B. As shown in FIG. 14, a unit recess 71 in which the circuit unit 40 is set and a circuit board 50 are set in the lower die 70B. A substrate recess 76 is provided.
The planar shape of the unit recess 71 is generally formed along the outer shape of the circuit unit 40, and the depth dimension of the unit recess 71 is equivalent to the plate thickness of the plate portion 43 of the first conductive member 41A. ing.

On the bottom surface of the unit recess 71 (the mounting surface on which the first conductive member 41A is mounted), only the circuit board 50 and the positioning pin 72 that positions the circuit unit 40 and the circuit board 50 at a time are positioned. A positioning boss 73 is provided.
Four positioning pins 72 are provided at positions corresponding to the second through holes 49 and the terminal connection holes 47 of the circuit unit 40. The positioning pins 72 are provided at the upper edge of the unit recess 71 and are arranged at a predetermined pitch along the longitudinal direction of the unit recess 71. The positioning pin 72 protrudes upward in a substantially circular cross section along the shapes of the second through hole 49 and the terminal connection hole 47, and the protruding dimension is larger than the thickness dimension of the circuit unit 40.

  The positioning boss 73 protrudes upward from a base portion 74 provided at the base thereof. The base portion 74 has a substantially square shape that can be fitted into the window portion 64 of the circuit unit 40, and the thickness dimension thereof is equal to the plate thickness dimension of the first conductive member 41A. The positioning boss 73 has a cylindrical shape whose sectional shape is slightly larger than that of the positioning pin 72 and can be fitted into a positioning hole 63 provided in the circuit board 50.

  The height positions of the projecting ends of the positioning pin 72 and the positioning boss 73 are substantially equal, and both of them project upward from the contact surface 75 of the lower mold 70B with the upper mold 70A. An upper recess (not shown) into which the projecting ends of the positioning pin 72 and the positioning boss 73 are fitted is provided.

  The unit recess 71 is provided with a flange recess 77 for forming the flange 62 of the fixed column 60. The trough recess 77 is provided at a position corresponding to the substrate fixing hole 53 and the unit fixing hole 48. The bowl recess 77 has a substantially circular shape that is slightly larger than the substrate fixing hole 53 and the unit fixing hole 48, and is shallowly recessed downward from the bottom surface of the unit recess 71.

  The board recess 76 has a shape opened to the left and right sides of the lower mold 70B, and a portion excluding the left edge and the lower edge of the circuit board 50 can be fitted. The depth dimension of the substrate recess 76 is equal to the thickness dimension of the circuit board 50. In addition, the left side edge part and lower side edge part of the circuit board 50 fitted in the recessed part 76 for board | substrates will be in the state protruded sideways from the lower mold | type 70B.

In manufacturing the circuit structure 30, as shown in FIGS. 14 and 15, first, the circuit unit 40 is set in the lower mold 70B.
When the circuit unit 40 is set in the lower mold 70 </ b> B, the corresponding terminal connection holes 47 and the second through holes 49 are fitted to the positioning pins 72 and set in the unit recesses 71. At this time, the positioning boss 73 protrudes upward from the window portion 64 of the circuit unit 40. Further, each positioning pin 72 penetrates the circuit unit 40, and a substantially half portion thereof protrudes upward from the circuit unit 40.

  Next, as shown in FIGS. 16 and 17, the circuit board 50 is set in the lower mold 70B. When setting the circuit board 50, the positioning hole 63 is fitted into the positioning boss 73, and the positioning pin 72 passing through the terminal connection hole 47 among the positioning pins 72 is inserted into the terminal insertion hole 51. , And set in the substrate recess 76. At this time, the first component connecting portion 44 and the second conductive member 41B of the circuit unit 40 are fitted to the fitting portion 52 of the circuit board 50, and the substrate is fixed at a position directly above the flange recess 77. The hole 53 and the unit fixing hole 48 are arranged on the front and back sides. Further, the positioning pin 72 and the positioning boss 73 penetrate the circuit board 50 and the circuit unit 40, and substantially half of the positioning pin 72 and the positioning boss 73 protrude upward.

Then, as shown in FIG. 18, the upper mold 70A and the lower mold 70B are closed, and a molten resin set at a predetermined temperature is injected and filled into a space formed therebetween. Then, the resin is filled into the substrate fixing hole 53, the unit fixing hole 48, and the bag recess 77 that are continuous in the vertical direction. Then, after the molten resin is solidified, when the upper mold 70A and the lower mold 70B are released, the base substrate 32 in which the circuit unit 40 and the circuit board 50 are integrated is formed.
Finally, when an electronic component such as the semiconductor switching element 33 is mounted on the surface of the base substrate 32 by reflow soldering or the like, the manufacture of the circuit structure 30 is completed.

Next, operations and effects of the second embodiment configured as described above will be described.
In the circuit configuration body 30 of the present embodiment, as in the first embodiment, the base substrate 32 is arranged with the first conductive member 41A and the second conductive member 41B overlapped on the front and back, and the insulating portion 42 is molded between them. Since the circuit unit 40 to be formed is assembled to the circuit board 50, it is possible to obtain an effect of downsizing the circuit structure 30 as compared with the case where all the conductive members 41 are arranged in the plane direction. .

  Further, the fitting part 52 of the circuit board 50 and the component connecting part 34 of the circuit unit 40 in the circuit structure 30 are provided in a row. Here, the component connection part 34 of the circuit unit 40 is a part to which heat of the semiconductor switching element 33 is directly transmitted, and such a part and the fitting part 52 are provided in a row so that semiconductor switching is performed. Heat from the element 33 is easily transferred to the circuit board 50 side. Thereby, the heat of the semiconductor switching element 33 is disperse | distributed and dissipated to the circuit board 50 side, Therefore Heat dissipation efficiency can be improved.

  Further, the circuit unit 40 has a configuration in which the component connecting portion 34 protrudes from the plate portion 43 disposed along the back surface of the circuit board 50, and the plate portion 43 and the circuit board 50 are provided in a row. The heat of the circuit unit 40 can be further easily transferred from the plate portion 43 to the circuit board 50 side, and the heat dissipation efficiency can be further improved.

<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 fitting portion 52 has a shape along the outer shape of the first component connecting portion 44 and the second conductive member 41B of the circuit unit 40 and opens in the front and back direction of the circuit board 50. The fitting portion does not necessarily have such an opening, and may be, for example, a notch formed by notching the periphery of the circuit board along the outer shape of the circuit unit.

  (2) In the above-described embodiment, the circuit board 50 and the circuit unit 40 are integrally held by the fixing pin 35 or the fixing column 60. It may be integrated by a method, for example, it may be integrated by an adhesive.

  (3) In the above embodiment, the circuit board 50 and the circuit unit 40 are integrally held by the fixing pin 35 or the fixing column 60. However, the present invention is not limited to this, and the circuit board 50 and the circuit unit 40 are not limited to any type. For example, the end of the plate part of the circuit unit is bent toward the circuit board to form a bent part, and the circuit board is formed with a through-hole into which the bent part can be inserted. May be integrated by inserting into the through hole and soldering.

  (4) In the second embodiment, the previously manufactured circuit unit 40 and the circuit board 50 are molded and integrated. However, the present invention is not limited to this, and the manufacture of the circuit unit and the circuit unit and the circuit board are integrated. For example, the conductive member and the circuit board that constitute the circuit unit may be molded at a time, and the insulating portion and the fixed column may be formed at a time.

DESCRIPTION OF SYMBOLS 10 ... Electric junction box 20 ... Case 30 ... Circuit structure 31 ... Circuit pattern 32 ... Base board 33 ... Semiconductor switching element (electronic component)
34 ... Component connection part 40 ... Circuit unit 41A ... First conductive member (component connection part of one conductive member)
41B ... 2nd conductive member (component connection part of the other conductive member)
42 ... Insulating part 43 ... Plate part 44 ... First component connecting part (one conductive member)
45 ... 2nd part connection part (the other conductive member)
50 ... Circuit board 52 ... Fitting part

Claims (7)

A circuit structure comprising a base substrate having a circuit pattern composed of a plurality of conductive members, and electronic components mounted on the front surface or the back surface of the base substrate,
The base substrate is a circuit structure in which a circuit unit in which the conductive members are arranged on the front and back sides and an insulating part is molded therebetween is assembled to the circuit board. Among the circuit units, the component connection part to which the terminal part of the electronic component is connected is the part of the conductive member arranged on the front and back, the component connection part of one conductive member is the component of the other conductive member It is provided protruding from the connection part side,
The circuit component according to claim 1, wherein the component connecting portion of the circuit unit is fitted in a fitting portion formed on the circuit board.   The circuit structure according to claim 1, wherein a gap is provided at least between the fitting portion and the component connection portion. The circuit unit has a form in which the component connection portion protrudes from a plate portion arranged along the front surface or the back surface of the circuit board.
The circuit structure according to claim 3, wherein a gap is provided between the plate portion and the circuit board.   The circuit structure according to claim 1 or 2, wherein at least the fitting portion and the component connecting portion are provided in a continuous manner. The circuit unit has a form in which the component connection portion protrudes from a plate portion arranged along the front surface or the back surface of the circuit board.
The circuit structure according to claim 5, wherein the plate portion and the circuit board are provided continuously.   An electrical junction box, wherein the circuit structure according to any one of claims 1 to 6 is accommodated in a case.

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