JP2016105677A - Circuit configuration body and circuit configuration body with radiator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit configuration body capable of keeping a circuit configuration body and a radiator in the closely contacting state for a period until an adhesive is cured without applying pressure to an electric component when the radiator is joined to the circuit configuration body, and also to provide the circuit configuration body with the radiator using the same.SOLUTION: A circuit configuration body 1 includes: a plurality of numbers of bus bars 11; a circuit board 12 which is laminated on one surface of the bus bar 11; an electronic component 13 mounted on the circuit board 12; and a ferromagnetic layer 14 which is laminated on the other surface of the bus bar 11 and formed of a ferromagnetic material. The ferromagnetic material contains one or more kinds of ferromagnetic metals selected from a group of consisting of Fe, Fe alloy, Ni, Ni alloy, Co, and Co alloy. The circuit configuration body 2 with the radiator includes: the circuit configuration body 1; and a radiator 22 which is joined to the surface on the side opposite to the bus bar 11 side in the ferromagnetic layer 14 via an adhesive layer 21.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a circuit structure and a circuit structure with a radiator.

  Conventionally, DC voltage converters, AC / DC converters, DC / AC inverters, and the like are used in the field of automobiles and the like. These devices usually incorporate a circuit structure. In general, the circuit structure includes a plurality of bus bars, a circuit board stacked on one surface of the bus bar, and electronic components mounted on the circuit board.

  In addition, for the purpose of efficiently exhausting the heat generated from the electronic components and maintaining the temperature of the entire circuit below a certain level to ensure the operation of the circuit structure, the surface of the bus structure in the circuit structure is thermosetting. The heat radiator is often joined by an adhesive.

  Prior art document 1 describes a technique for configuring a circuit configuration body by mounting electronic components on a circuit body joined to a heat dissipation body, thereby obtaining a circuit configuration body with a heat dissipation body. Yes.

JP 2005-151624 A

  When bonding the circuit component and the radiator with an adhesive, in order to ensure sufficient bonding force between the circuit component and the radiator, the adhesive is cured with the circuit component pressed against the radiator. There is a need. However, many electronic components that are vulnerable to pressure are mounted on the circuit structure. Therefore, when joining the heat sink to the circuit structure, pressure is applied to the circuit structure and the heat sink to keep them in close contact until the adhesive is cured without applying pressure to the electronic components. It is difficult.

  On the other hand, it is conceivable to use a jig that presses the circuit structure from above at a position avoiding the mounted electronic component. However, even if such a method is used, it can be pressed only at a position avoiding the mounted electronic component. For this reason, it is difficult to ensure a sufficient bonding force between the circuit component and the heat radiator.

  The present invention has been made in view of the above background, and when joining a heat sink to a circuit component, the circuit component and the heat are dissipated until the adhesive is cured without applying pressure to the electronic component. It is an object of the present invention to provide a circuit structure capable of keeping a body in close contact with each other, and a circuit structure with a radiator using the same.

  One embodiment of the present invention includes a plurality of bus bars, a circuit board stacked on one side of the bus bar, an electronic component mounted on the circuit board, and a ferromagnetic layer stacked on the other side of the bus bar. And a ferromagnetic layer made of a material.

  According to another aspect of the present invention, there is provided the radiator, wherein the circuit configuration body and the radiator that is bonded to the surface of the ferromagnetic layer opposite to the bus bar side through an adhesive layer are provided. It is in the circuit structure.

  In the circuit structure, a ferromagnetic layer made of a ferromagnetic material is laminated on the other surface of the bus bar. Therefore, when joining the radiator, the circuit component is bonded to the surface opposite to the bus bar in the ferromagnetic layer with an adhesive, and then the permanent magnet or electromagnet is used from the radiator side. It becomes possible to attract the ferromagnetic layer of the circuit structure to the heat sink. Therefore, the circuit structure can press the circuit structure against the heat radiating body without applying pressure to the electronic components, and the circuit structure and the heat radiating body are kept in close contact until the adhesive is cured. Can keep.

  Since the said circuit structure with a heat radiator uses the said circuit structure, it is easy to ensure sufficiently the joining force of a circuit structure and a heat radiator.

FIG. 3 is a perspective view schematically showing a main part of the circuit configuration body of Example 1. It is explanatory drawing for demonstrating typically the method to join a circuit body of Example 1, and to manufacture a circuit structure body with a heat radiator. It is explanatory drawing for demonstrating typically the method to join a circuit body of Example 2, and to manufacture a circuit body with a heat radiator by joining a heat radiator.

  Specific examples of the ferromagnetic material in the circuit structure include Fe, Fe alloy, Ni, Ni alloy, Co, and Co alloy. These can be used alone or in combination of two or more. These have ferromagnetism and excellent thermal conductivity. For this reason, the ferromagnetic layer hardly disturbs heat conduction, and it is easy to suppress a decrease in the heat conductivity of the entire circuit structure. Among the above ferromagnetic materials, particularly preferably, an alloy of Fe and Co such as pure iron, ferrite, and permendur can be suitably used from the viewpoints of thermal conductivity, magnetization, demagnetization due to temperature, and the like. .

  In the above circuit structure, the ferromagnetic layer may be laminated on the other surface of the bus bar so that the bus bars are not electrically connected. Specifically, the ferromagnetic layer can be laminated by engaging with a bus bar, for example. In this case, for example, the engagement hole or the engagement protrusion can be provided on the bus bar side, and the engagement protrusion or the engagement hole can be provided on the ferromagnetic layer side. In addition, the ferromagnetic layer can be specifically laminated on the bus bar via an adhesive, for example. In this case, as the adhesive, various adhesives having thermal conductivity can be suitably used so as not to prevent thermal conduction from the circuit component to the heat radiating body. The thermal conductivity of the adhesive can be improved by, for example, controlling the molecular orientation of the resin adhesive or adding a filler having thermal conductivity.

  In the above-described circuit structure, the ferromagnetic layer may be laminated on the other surface of the bus bar in the same pattern as a bus bar pattern including a plurality of bus bars, for example.

  In this case, the ferromagnetic layer is not disposed across the bus bars. Therefore, electrical insulation between each bus bar can be ensured. In this case, the ferromagnetic layer can be laminated by engaging with the bus bar. The ferromagnetic layer can also be laminated on the bus bar via an adhesive. The adhesive may be electrically insulating or conductive.

  In the above circuit structure, the ferromagnetic layer may be composed of, for example, a single plate-like body, and may be laminated on the other surface of the bus bar via an electrical insulating layer.

  In this case, although the ferromagnetic layer is disposed so as to straddle each bus bar, an electrical insulating layer exists between the ferromagnetic layer and the bus bar. Therefore, electrical insulation between each bus bar can be ensured. Furthermore, since the ferromagnetic layer is a single plate-like body, the structure of the ferromagnetic layer is simplified, and a circuit structure excellent in manufacturability can be obtained. In this case, the electrical insulation layer can be composed of various adhesives having electrical insulation, for example.

  Specific examples of the adhesive described above include, for example, an epoxy adhesive, a silicone adhesive, an acrylic adhesive, a hot melt adhesive, an anaerobic adhesive, an epoxy adhesive sheet, and a silicone adhesive. A thermosetting adhesive such as a sheet can be suitably used. The above adhesives control the molecular orientation to ensure thermal conductivity and insulation, and have high thermal conductivity and insulation properties such as alumina, aluminum hydroxide, aluminum nitride, magnesia, silicon oxide, boron nitride. The heat conductivity and insulation can be improved as appropriate by mixing fillers.

  In the circuit structure with a radiator, it is preferable to use an adhesive layer that has good thermal conductivity so that the adhesive layer does not hinder thermal conduction as an adhesive layer that bonds the bus bar and the radiator. As the adhesive constituting the adhesive layer, the above-described adhesive can be suitably used.

  In addition, each structure mentioned above can be arbitrarily combined as needed, in order to acquire each effect etc. which were mentioned above.

  Hereinafter, the circuit structure of an Example and the circuit structure with a heat radiator are demonstrated using drawing. In addition, about the same member, it demonstrates using the same code | symbol.

Example 1
The circuit structure of Example 1 and the circuit structure with a radiator will be described with reference to FIGS. 1 and 2. As shown in FIGS. 1 and 2, the circuit configuration body 1 of this example includes a plurality of bus bars 11, a circuit board 12, an electronic component 13, and a ferromagnetic layer 14.

  The plurality of bus bars 11 are electrically connected to the electronic component 13 by reflow soldering to constitute a power circuit. In this example, a predetermined bus bar pattern is constituted by a plurality of bus bars 11. The plurality of bus bars 11 are formed of a plate-like body. Specifically, the plurality of bus bars 11 are configured by appropriately bending and dividing a bus bar constituting plate (not shown) formed by punching a predetermined metal plate by press working. Specifically, as the metal plate, one obtained by applying Sn or Sn plating to the surface of a base metal made of copper or a copper alloy is used.

  The circuit board 12 is laminated on one surface of the bus bar 11. The circuit board 12 has a control circuit (not shown) for controlling the electronic component 13 and is electrically connected to the electronic component 13 by reflow soldering. In this example, the circuit board 12 has a plurality of board side openings 121 penetrating in the board thickness direction. The board-side opening 121 is a part where the terminal part of the electronic component 13 is disposed in order to reflow solder the electronic component 13 to the surface of the bus bar 11 exposed in the board-side opening 121. The bus bar 11 and the circuit board 12 are joined together by a thermosetting adhesive 15 such as an epoxy adhesive. The adhesive 15 can be changed to a pressure-sensitive adhesive sheet.

  The electronic component 13 is mounted on the circuit board 12. Specifically, the electronic component 13 is a switching element. Specifically, a semiconductor switching element 131 and a mechanical relay switch 132 are used as the switching element. The electronic component 13 is reflow soldered to the surface of the bus bar 11 through the board side opening 121. In this example, specifically, the mechanical relay switch 132 as the electronic component 13 specifically includes a bus bar connection terminal 132a and a board connection terminal 132b. The bus bar connection terminal 132 a is reflow soldered to the surface of the bus bar 11 through the board side opening 121. The board connection terminal 132b is soldered to the land portion 121 of the circuit board 12. On the other hand, the semiconductor switching element 131 as the electronic component 13 has a drain terminal (not shown), a source terminal (not shown), and a gate terminal (not shown). The drain terminal and the source terminal are reflow soldered to the surface of the bus bar 11 through the board side opening 121. The gate terminal is reflow soldered to a land portion (not shown) of the circuit board 12.

  The ferromagnetic layer 14 is laminated on the other surface of the bus bar 11 and is made of a ferromagnetic material. In this example, specifically, the ferromagnetic layer 14 is laminated on the other surface of the bus bar 11 in the same pattern as the bus bar pattern constituted by a plurality of bus bars 11. Therefore, each part which comprises the ferromagnetic layer 14 laminated | stacked on the bus-bar 11 is mutually spaced apart. The ferromagnetic layer 14 is laminated on the bus bar 11 via an adhesive (not shown). Specifically, the adhesive is a thermosetting epoxy adhesive.

  In the circuit component 1, the ferromagnetic material is specifically one or more ferromagnetic metals selected from the group consisting of Fe, Fe alloy, Ni, Ni alloy, Co, and Co alloy. Contains. More specifically, in this example, the ferromagnetic material is Fe. The ferromagnetic layer has a thickness of 0.5 to 3 mm.

  Next, a circuit structure with a heat radiator will be described. As shown in FIG. 2, the circuit component 2 with a heat dissipator of this example is bonded to the circuit component 1 described above and the surface of the ferromagnetic layer 14 opposite to the bus bar 11 via an adhesive layer 21. The heat radiator 22 is provided.

  In this example, the heat radiator 22 is made of aluminum. In FIG. 2, the heat radiator 22 is schematically drawn in a flat plate shape. Usually, an uneven portion is formed on the outer surface of the radiator 22 to promote heat dissipation.

  In this example, the adhesive constituting the adhesive layer 21 is specifically a thermosetting epoxy adhesive. Moreover, the thickness of the adhesive bond layer 21 is 0.05-0.3 mm.

  The circuit structure 2 with a heat radiator of this example can be manufactured as follows, for example. In addition, the manufacturing method of the circuit structure 2 with a heat radiator is not limited to this.

  A laminated body 3 is prepared in which the heat radiator 22, the uncured adhesive 210, and the circuit component 1 are laminated in this order. Note that the laminate 3 is formed by, for example, applying an uncured adhesive 210 to the surface of the radiator 22 on the circuit component 1 side, and applying a ferromagnetic layer on the surface of the radiator 22 to which the uncured adhesive 210 is applied. The circuit structure 1 can be prepared by attaching the 14 side facing each other.

  Next, a permanent magnet or an electromagnet M is disposed on the side opposite to the circuit component 1 side in the heat radiating body 22. Then, the ferromagnetic layer 14 of the circuit component 1 is attracted to the radiator 22 by the magnetic force of the permanent magnet or the electromagnet M. Then, with this state maintained, the uncured adhesive 210 is cured to form the adhesive layer 21. Thereby, the heat radiating body 22 is joined to the circuit structural body 1, and the circuit structural body 2 with a heat radiating body is obtained.

  Next, the effect of the circuit structure of this example and the circuit structure with a radiator will be described.

  In the circuit structure 1 of this example, a ferromagnetic layer 14 made of a ferromagnetic material is laminated on the other surface of the bus bar 11. Therefore, in the circuit configuration body 1 of this example, when the heat radiating body 22 is joined, the heat radiating body 22 is bonded to the surface opposite to the bus bar 11 side of the ferromagnetic layer 14 with the adhesive 210, and then the heat radiating body. It becomes possible to attract the ferromagnetic layer 14 of the circuit component 1 to the heat radiating body using the permanent magnet or the electromagnet M from the 22 side. Therefore, the circuit configuration body 1 of this example can press the circuit configuration body 1 against the heat radiating body 22 without applying pressure to the electronic component 13, and the circuit configuration body 1 until the adhesive 210 is cured. And the radiator 22 can be kept in close contact.

  Since the circuit component 2 with a heat radiator of this example uses the circuit component 1 of this example, it is easy to ensure a sufficient bonding force between the circuit component 1 and the heat radiator 22.

  In the circuit structure 1 of this example, the ferromagnetic layer 14 is laminated on the other surface of the bus bar 11 in the same pattern as the bus bar pattern. Therefore, in the circuit configuration body 1 of this example, the ferromagnetic layer 14 is not disposed so as to straddle the bus bars 11. Therefore, the circuit configuration body 1 of this example can ensure electrical insulation between the bus bars 11.

(Example 2)
The circuit structure of Example 2 and the circuit structure with a radiator will be described with reference to FIG. The circuit structure 1 of this example is that the ferromagnetic layer 14 is composed of a single plate-like body, and is laminated on the other surface of the bus bar 11 via the electrical insulating layer 16 in the first embodiment. This is different from the circuit structure 1 of FIG. Other configurations are the same as those of the first embodiment.

  In the circuit configuration body 1 of this example, the plate-like body constituting the ferromagnetic layer 14 is made of a ferromagnetic material. More specifically, in this example, the ferromagnetic material is an alloy of Fe and Co. Moreover, the thickness of the ferromagnetic layer 14 is 0.5-2 mm.

  In the circuit structure 1 of this example, the electrical insulating layer 16 is formed of an electrically insulating adhesive. Specifically, the adhesive is an epoxy-based adhesive.

  In the circuit component 2 with a heat radiator of this example, a heat radiator 22 is joined to the circuit component 1 of this example. Other configurations are the same as those of the first embodiment.

  Next, the effect of the circuit structure of this example and the circuit structure with a radiator will be described.

  In the circuit configuration body 1 of this example, the ferromagnetic layer 14 is composed of a single plate-like body, and is laminated on the other surface of the bus bar 11 via the electrical insulating layer 16. Therefore, in the circuit configuration body 1 of this example, the ferromagnetic layer 14 is disposed so as to straddle between the bus bars 11, but the electrical insulating layer 16 exists between the ferromagnetic layer 14 and the bus bar 11. To do. Therefore, the circuit configuration body 1 of this example can ensure electrical insulation between the bus bars 11. Furthermore, in the circuit configuration body 1 of this example, since the ferromagnetic layer 14 is a single plate-like body, the structure of the ferromagnetic layer 14 is simplified and the productivity is excellent. Other functions and effects are the same as those of the first embodiment.

  As mentioned above, although the Example of this invention was described in detail, this invention is not limited to the said Example, A various change is possible within the range which does not impair the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Circuit structure 11 Bus bar 12 Circuit board 13 Electronic component 14 Ferromagnetic layer 2 Circuit structure with a heat radiator 21 Adhesive layer 22 Heat radiator

Claims (5)

Multiple busbars,
A circuit board laminated on one side of the bus bar;
Electronic components mounted on the circuit board;
And a ferromagnetic layer formed on the other side of the bus bar and made of a ferromagnetic material.   2. The ferromagnetic material according to claim 1, wherein the ferromagnetic material contains one or more ferromagnetic metals selected from the group consisting of Fe, Fe alloy, Ni, Ni alloy, Co, and Co alloy. The circuit structure described.   3. The circuit structure according to claim 1, wherein the ferromagnetic layer is laminated on the other surface of the bus bar in the same pattern as a bus bar pattern including a plurality of the bus bars.   3. The circuit structure according to claim 1, wherein the ferromagnetic layer is composed of a single plate-like body, and is laminated on the other surface of the bus bar via an electrical insulating layer. .   It has the circuit structure object according to any one of claims 1 to 4 and a heat radiator joined to the field opposite to the bus bar side in the ferromagnetic layer via an adhesive layer. A circuit component with a radiator.

Images