JP6044412B2 - Connection structure between lead terminal and circuit board, circuit structure and electrical connection box - Google Patents

Description

  The present invention relates to a connection structure between a lead terminal and a circuit board, a circuit structure, and an electrical connection box.

Conventionally, a technique is known in which lead terminals of electronic components are soldered through through holes in a circuit board.
Patent Document 1 describes a technique in which a lead terminal of an electronic component is inserted into a through hole of a circuit board formed by molding a bus bar with a synthetic resin material, and is flow soldered.

JP 2011-159868 A

  By the way, in patent document 1, the lead terminal of the electronic component inserted in the through-hole from one side of the circuit board protrudes outside from the other side of the through-hole. Thus, if the tip of the lead terminal protrudes outside the through hole, the flat surface of the heat dissipation member cannot be superimposed on the circuit board. Therefore, there is a problem that it is necessary to prepare a dedicated heat radiating member corresponding to the shape of the lead terminal, such as forming a dent corresponding to the shape of the lead terminal in the heat radiating member.

  The present invention has been completed based on the above circumstances, and has a connection structure and circuit configuration between a lead terminal and a circuit board that can overlap an existing heat radiation member on the circuit board while improving heat dissipation. The object is to provide a body and an electrical junction box.

In the connection structure between the lead terminal and the circuit board according to the present invention, the lead terminal of the electronic component is inserted into a through hole provided so as to be continuous with the conductive path of the circuit board, and the lead terminal and the conductive path of the circuit board are connected. a connecting structure between the lead terminals and the circuit board formed by soldering, the circuit board, Zhang projecting a flat plate-like portion, from the plane of the plate portion at the periphery of the through hole stepwise The lead terminal inserted into the through hole is provided on the circuit board so that the tip of the lead terminal is located in the through hole penetrating the plate-like portion and the protruding portion. Soldered, and the flat surface side of the heat radiating member where the region corresponding to the through hole is a flat surface overlaps the surface of the circuit board opposite to the side where the protruding portion protrudes. is there.

  According to this configuration, the lead terminal inserted into the through hole is soldered to the circuit board so that the tip of the lead terminal is located in the through hole that penetrates the plate-like portion and the overhang portion. Compared with the case where the tip of the lead terminal protrudes outside the through hole, the lead terminal is less likely to get in the way when the heat radiating member is superimposed on the surface of the circuit board opposite to the side where the overhanging part projects. . Therefore, without preparing a dedicated heat radiating member that matches the protruding shape of the lead terminal, the flat surface of the heat radiating member having a (existing) flat surface that is generally used is opposite to the overhanging portion of the circuit board. It can be stacked on the side surface. In addition, even when the flat surface of the heat dissipation member is overlapped on the surface of the circuit board opposite to the overhanging portion, the flat surfaces can be overlapped with each other, so that heat dissipation can be improved. Therefore, it is possible to overlap the existing heat dissipation member on the circuit board while improving the heat dissipation.

The circuit component of the present invention includes an electronic component having a lead terminal, a flat plate-like portion, and an overhang portion that projects from the surface of the plate-like portion around the through-hole connected to the conductive path. A circuit board comprising: a solder part soldered to the lead terminal and the circuit board so that a tip of the lead terminal is positioned in the through-hole penetrating the plate-like part and the projecting part The flat surface side of the heat radiating member in which the region corresponding to the through hole is a flat surface is superimposed on the surface of the circuit board opposite to the side on which the protruding portion extends.

  According to this configuration, the solder portion soldered to the lead terminal and the circuit board so that the tip of the lead terminal inserted through the through hole is located in the through hole penetrating the plate-like portion and the overhang portion. Compared to the case where the tip of the lead terminal protrudes to the outside of the through hole, the lead terminal is obstructed when the heat radiating member is overlaid on the surface of the circuit board opposite to the side where the protruding part protrudes. It is hard to become. Therefore, without preparing a dedicated heat radiating member that matches the protruding shape of the lead terminal, the flat surface of the heat radiating member having a (existing) flat surface that is generally used is opposite to the overhanging portion of the circuit board. It can be stacked on the side surface. Moreover, even if the flat surface of the heat dissipation member is overlapped on the surface of the circuit board opposite to the overhanging portion, the flat surfaces can be overlapped with each other, so that heat dissipation can be improved. Therefore, it is possible to overlap the existing heat dissipation member on the circuit board while improving the heat dissipation.

It is preferable to have the following configuration as an embodiment of the above configuration.
The circuit board has a diameter-enlarged portion whose diameter is increased in the through-hole, and a tip of the lead terminal is disposed in the diameter-enlarged portion.

The circuit board is a bus bar board, and the protruding portion is formed by performing a half punch process on the bus bar board.

The circuit board is a bus bar board, and the overhang is formed by burring the bus bar board.

In the electronic component, the lead terminal is led out from a resin package, and the lead terminal is arranged in a state where a tip of the lead terminal is arranged in the through hole. The soldering jig has a length that allows the soldering tool to enter.

-It is set as the electrical junction box provided with the said circuit structure and the case which accommodates the said circuit structure.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to overlap the heat radiating member of the existing structure on a circuit board, improving heat dissipation.

Sectional drawing which shows the structure of the electrical junction box of Embodiment 1 roughly Sectional drawing which expands and shows the state by which the lead terminal was soldered to the circuit board The top view which expands and shows the overhang | projection part of a circuit board, and its vicinity Sectional drawing which expands and shows the state by which the lead terminal of the reference example 1 was soldered to the circuit board The top view which expands and shows the overhang | projection part of a circuit board, and its vicinity

<Embodiment 1>
An embodiment of the present invention will be described with reference to FIGS.
The electrical junction box 10 of the present embodiment is mounted on a vehicle such as an electric vehicle or a hybrid vehicle, and can be used as a device that distributes power supplied from a power source such as a battery to a load such as an in-vehicle electrical component. . Hereinafter, the vertical direction will be described with reference to FIG.

As shown in FIG. 1, the electrical junction box 10 includes a circuit structure 11 and a case 27 that houses the circuit structure 11.
The case 27 has a box shape with an opening at the bottom, and covers the circuit structure 11 so as to cover the upper surface of the circuit structure 11.

As shown in FIG. 2, the circuit structure 11 includes an electronic component 12 having lead terminals 14, a circuit board 15 on which the electronic component 12 is mounted, and a heat dissipation member 26 that is superimposed on the circuit board 15.
The electronic component 12 is a thermally weak component, and for example, a film capacitor can be used. The thermally weak component is, for example, a thermal weakness that is not suitable for heating by a reflow furnace during reflow soldering.

The electronic component 12 has a pair of lead terminals 14 led out from a package 13 made of synthetic resin.
The lead terminal 14 has, for example, a rectangular cross section.

  The circuit board 15 is pressed with a plate material made of plated metal such as copper or copper alloy (in this embodiment, for example, 1.2 mm, and may have a thickness in the range of 0.5 to 1.2 mm). This is a bus bar substrate punched out by a machine, and a conductive path is formed on a plane. The circuit board 15 may be formed only from the bus bar board, but the bus bar board on which a plurality of conductive paths are formed may be integrally fixed with resin to form the circuit board.

The circuit board 15 includes a flat plate-like portion 16 and an overhang portion 17 that projects upward from the upper surface 16A of the plate-like portion 16.
The plate-like portion 16 has an upper surface 16A and a lower surface 16B that are flat and have a predetermined thickness.
The projecting portion 17 projects in a circular shape from the surface of the plate-like portion 16, and projects from the upper surface 16 </ b> A of the plate-like portion 16 with a predetermined thickness (substantially the same thickness as the plate thickness of the plate-like portion 16).

The overhanging portion 17 has a circular through hole 18 penetrating the circuit board 15 at the center, and the overhanging portion 17 has a shape protruding from the surface of the plate-like portion 16 around the through hole 18. Yes.
The through hole 18 is provided on the reduced diameter portion 19 (in the embodiment, the diameter of the reduced diameter portion is 1.2 mm, for example) provided on the overhang portion 17 side, and on the plate-like portion 16 side, and the hole diameter is reduced. A diameter-enlarged portion 20 that is expanded in a stepped shape (concentric shape) with respect to the portion 19 is provided.

  The overhanging portion 17 is formed by subjecting a metal plate material to half punching with a press. The through hole 18 may be formed in the metal plate material before the harp punching process or after the harp punching process.

  The lead terminal 14 of the electronic component 12 is inserted from the upper side of the circuit board 15 into the through hole 18 and the tip thereof is positioned in the enlarged diameter portion 20 (in FIG. 2, the tip of the lead terminal 14 is in the vertical direction). In this case, it is soldered to the circuit board 15 in a state of being arranged in the intermediate portion between the lower surface 17B of the overhanging portion 17 and the lower surface 16B of the plate-like portion 16).

The solder portion 21 formed by this soldering is reduced in diameter so that the fillets 22 and 23 are connected to the angled fillets 22 and 23 formed so as to be in close contact with the upper surface 17A and the lower surface 17B of the overhang portion 17. And a filling portion 24 filled in the portion 19.
The lower fillet 23, together with the distal end portion of the lead terminal 14, is entirely contained within the enlarged diameter portion 20.

The soldering operation can be performed by a soldering robot.
Specifically, the lead terminal 14 is inserted between the lower surface 13A of the package 13 and the upper surface 17A of the overhanging portion 17 for soldering (not shown) in a state where the lead terminal 14 is inserted into the through hole 18 to a position to be soldered. It has a length that allows the robot's iron (an example of a “jig”; the upper end J1 and the lower end J2 of the iron are schematically shown in FIG. 2) to enter (between the package 13 and the overhanging portion 17). Has a space where the soldering iron of the robot for soldering can enter).

With the circuit board 15 and the electronic component 12 held by a temporary holding jig, a soldering iron is inserted between the package 13 and the overhanging portion 17 to penetrate the melted solder through the iron. Pour into hole 18.
The solder part 21 is formed by the solder solidifying.

An insulating synthetic resin layer 25 (for example, an adhesive or an insulating adhesive sheet) is disposed between the circuit board 15 and the heat dissipation member 26.
The heat radiating member 26 has a plate shape thicker than the plate-like portion 16 and is made of a metal having high thermal conductivity.
The upper surface of the heat dissipating member 26 is a flat surface. When the circuit board 15 is placed on the upper surface of the heat dissipating member 26, the lower surface 16B of the plate-like portion 16 and the upper surface of the heat dissipating member 26 on the circuit board 15 are synthetic resin. It adheres through the layer 25.
In the present embodiment, the lower surface of the heat radiating member 26 is flat. However, heat radiating fins may be provided on the lower surface of the heat radiating member 26 in order to enhance heat dissipation.

According to the present embodiment, the following operations and effects are achieved.
According to the present embodiment, the lead terminal 14 inserted into the through hole 18 has a circuit board so that the tip of the lead terminal 14 is located in the through hole 18 that penetrates the plate-like portion 16 and the overhang portion 17. 15, the lead terminal 14 is less likely to get in the way when the heat dissipating member 26 is stacked on the circuit board 15, as compared with the case where the tip of the lead terminal 14 protrudes outside the through hole 18. . Therefore, without providing a dedicated heat radiating member that matches the protruding shape of the lead terminal 14, the overhanging portion of the circuit board 15 on the flat surface of the heat radiating member 26 that has a generally used (existing) flat surface is provided. It becomes possible to overlap the surface on the opposite side to 17. Even if the surface opposite to the overhanging portion 17 in the circuit board 15 is overlapped on the flat surface of the heat dissipation member 26 as described above, the flat surfaces overlap each other, so that the heat dissipation can be improved. Therefore, the existing heat radiating member 26 can be stacked on the circuit board 15 while improving the heat dissipation.

< Reference Example 1 >
Next, Reference Example 1 of the present invention will be described with reference to FIGS.
In the first embodiment, the part to which the lead terminal 14 of the circuit board 15 is connected is half-punched, but in Reference Example 1 , the part to which the lead terminal 14 of the circuit board 33 is connected is burring processed. Is given. Others are the same as those in the first embodiment, and therefore, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

As shown in FIG. 4, the protruding portion 28 of the circuit board 33 protrudes upward (in a substantially orthogonal direction) with respect to the surface of the plate-like portion 16.
The through-hole 29 has a circular shape, and the entire vertical direction from the protruding portion 28 to the plate-like portion 16 has substantially the same diameter.

The lead terminal 14 of the electronic component 12 is inserted into the through hole 29 from the upper side of the circuit board 15, and the tip thereof is positioned slightly above the lower surface 16 </ b> B of the plate-like portion 16 in the through hole 29. Soldered to the substrate 15.
Between the lower surface 13A of the package 13 and the upper surface of the overhang portion 28, a space is formed in which a soldering iron of a soldering robot (not shown) can enter.

The upper side of the solder part 30 formed by soldering is disposed above the overhanging part 28 to form an angled fillet 31 centered on the lead terminal 14.
A lower end 32 of the solder part 30 is formed along the lower surface 16B of the circuit board 15.

<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 circuit board 15 is a bus bar board obtained by pressing a metal plate material. However, the circuit board 15 is not limited to this. For example, the bus bar board is stacked on a printed board on which a conductive path is printed and wired. You may make it comprise a circuit board.

(2) The position of the tip of the lead terminal 14 is not limited to the position of the above embodiment as long as it is within the through hole 18. For example, the tip of the lead terminal 14 may be positioned at substantially the same position as the position of the lower surface 16B of the plate-like portion 16 (a position that does not protrude from the lower surface 16B of the plate-like portion 16).

(3) Although the circuit board 15 of the said embodiment shall be provided in the electrical junction box which distributes the electric power of a vehicle, it is also possible to apply this invention to circuit boards other than this.

(4) In the above embodiment, the electronic component 12 is a film capacitor. However, the present invention is not limited to this, and other known electronic components can also be used. Further, the number of lead terminals 14 of the electronic component is not limited to two in the above embodiment, and may be three or more. Furthermore, the arrangement of the electronic components on the circuit board 15 can be arbitrarily arranged depending on the application.

DESCRIPTION OF SYMBOLS 10 ... Electric junction box 11 ... Circuit structure 12 ... Electronic component 13 ... Package 14 ... Lead terminal 15 ... Circuit board 16 ... Plate-shaped part 17, 28 ... Overhang portion 18, 29 ... through hole 19 ... reduced diameter portion 20 ... expanded diameter portion 21, 30 ... solder portion 22, 23, 31 ... fillet 24 ... filling portion 26. ..Heat dissipation member 27 ... Case J1 ... Upper end of soldering jig J2 ... Lower end of soldering jig

Claims (11)

Connection structure between a lead terminal and a circuit board in which a lead terminal of an electronic component is inserted into a through hole provided so as to be continuous with a conductive path of the circuit board and the lead terminal and the conductive path of the circuit board are soldered Because
The circuit board includes a flat plate-like portion, and an overhang portion that protrudes in a step shape from the surface of the plate-like portion around the through hole,
The lead terminal inserted into the through hole is soldered to the circuit board so that the tip of the lead terminal is located in the through hole penetrating the plate-like portion and the overhang portion,
A lead terminal and a circuit board having a structure in which the flat surface side of the heat radiating member in which a region corresponding to the through hole is a flat surface is overlapped on a surface of the circuit board opposite to a side where the protruding portion protrudes Connection structure with. 2. The lead terminal and circuit board according to claim 1, wherein the circuit board has a diameter-enlarged portion in which a hole diameter is increased in the through-hole, and a tip of the lead terminal is disposed in the diameter-expanded portion. Connection structure with. 3. The connection between the lead terminal and the circuit board according to claim 1, wherein the circuit board is a bus bar board, and the overhang portion is formed by subjecting the bus bar board to half punching. Construction. The circuit board is a bus bar substrate, wherein the projecting portion is any one of claims 1 to 3, from the surface of the plate-like portion protrudes at substantially the same thickness as the plate thickness of the plate-like portion A connection structure between the lead terminal described in the section and the circuit board. In the electronic component, the lead terminal is led out from a resin package,
The lead terminal has a length that allows a soldering jig to enter between the package and the overhanging portion in a state in which a tip of the lead terminal is disposed in the through hole. Item 5. A connection structure between the lead terminal according to any one of Items 4 and the circuit board. An electronic component having a lead terminal;
A circuit board comprising a plate-like plate-like portion and a projecting portion projecting in a step shape from the surface of the plate-like portion around the through-hole connected to the conductive path;
A solder portion soldered to the lead terminal and the circuit board so that the tip of the lead terminal is located in the through hole penetrating the plate-like portion and the overhang portion;
The circuit structure in which the flat surface side of the heat radiating member in which the region corresponding to the through hole is a flat surface is overlapped on the surface of the circuit board opposite to the side where the protruding portion extends. The circuit structure according to claim 6, wherein the circuit board has a diameter-enlarged portion whose diameter is increased in the through-hole, and a tip of the lead terminal is disposed in the diameter-enlarged portion. The circuit structure according to claim 6 or 7, wherein the circuit board is a bus bar board, and the projecting portion is formed by subjecting the bus bar board to a half punch process. The circuit board is a bus bar substrate, wherein the projecting portion is any one of claims 8 claims 6 overhanging substantially the same thickness as the plate thickness of the plate-shaped portion from the surface of the plate-like portion The circuit structure according to item . In the electronic component, the lead terminal is led out from a resin package,
The lead terminal has a length that allows a soldering jig to enter between the package and the overhanging portion in a state in which a tip of the lead terminal is disposed in the through hole. Item 10. The circuit structure according to any one of Items 9. An electrical junction box comprising: the circuit structure according to any one of claims 6 to 10; and a case for housing the circuit structure.

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