JP4110995B2 - Circuit structure and inspection method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a circuit structure used as a vehicle power distributor for distributing power from a common in-vehicle power source to a plurality of electronic units, and an inspection method thereof.
[0002]
[Prior art]
Conventionally, as a means for distributing electric power from a common in-vehicle power source to each electronic unit, an electric connection box is known in which a power circuit unit is configured by stacking a plurality of bus bar substrates, and a fuse and a relay switch are incorporated therein. ing.
[0003]
In recent years, switching elements such as FETs have been interposed between the input terminal and the output terminal in order to reduce the size of the electrical connection box that distributes power from a common in-vehicle power supply to each electronic unit and to achieve high-speed switching control. Development of circuit structures is underway. In such a circuit structure, it is desirable to effectively cool the heat generated from the switching element, etc. From this point of view, the circuit arrangement of the heat radiating member formed of a material having excellent thermal conductivity such as aluminum The thing which adhered the power circuit part on the surface via the insulating layer has come to be proposed (for example, refer to Patent Document 1).
[0004]
[Patent Document 1]
JP 11-204700 A
[0005]
[Problems to be solved by the invention]
In the circuit structure in which the power circuit unit is bonded onto the circuit arrangement surface of the heat dissipation member as described above, the heat generated from the power circuit unit is efficiently dissipated to the outside, and the heat dissipation member, the power circuit unit, In order to maintain the insulating property, the circuit arrangement surface and the power circuit portion are well bonded, and the thickness of the insulating layer (including at least a layer made of an adhesive) interposed therebetween is appropriate. It must be within range. Therefore, such inspection of the adhesion state is very important for quality control.
[0006]
On the other hand, it is considered that the power circuit unit is made thinner, and it is necessary to effectively protect the power circuit unit with a case, and the adhesion state can be inspected while satisfying these requirements. It has become a big issue.
[0007]
The present invention has been made against the background of the prior art, and inspecting the adhesion state between the heat circuit member and the heat circuit member for cooling the power circuit unit while reducing the thickness and protecting the power circuit unit. It is an object of the present invention to provide a circuit configuration body and an inspection method thereof that make it possible to easily perform the above.
[0008]
[Means for Solving the Problems]
As means for solving the above-mentioned problems, the present invention provides a power circuit unit configured by superimposing a plurality of bus bars on a circuit board in a state of being arranged on a substantially plane, and the bus bar of the power circuit unit includes an insulating layer. A heat dissipating member having a circuit disposing surface bonded thereto, and being attached to the heat dissipating member so as to protect the circuit disposing portion from the outside, and at least a part of the circuit disposing surface in the mounted state. A case having an opening to be exposed to the outside, and a contact for measuring the position of the surface of the circuit arrangement surface in which the power circuit portion and the insulating layer are not provided. And a contact for measuring the position with respect to the bus bar is provided in a portion of the circuit board of the power circuit portion that is exposed to the outside through the opening of the case. In which the substrate side contact insertion holes for effecting touch is provided.
[0009]
According to the present invention, a plurality of bus bars are stacked on a circuit board in a state of being arranged on a substantially flat surface, whereby a thin power circuit unit is configured, and the bus bar of the power circuit unit is interposed via an insulating layer. By adhering to the circuit arrangement surface of the heat radiating member, the heat generated by the power circuit unit is released to the outside through the heat radiating member. Furthermore, the circuit arrangement portion is protected from the outside by a case attached to the heat dissipation member.
[0010]
Here, in order to sufficiently obtain the cooling effect of the power circuit portion by the heat radiating member and to ensure the insulation reliability between the two, the degree of adhesion between the bus bar of the power circuit portion and the circuit arrangement surface of the heat radiating member The thickness of the insulating layer interposed between them is important. However, since the contact insertion holes are respectively provided in the case and the control circuit board, the contact for position measurement is made using these contact insertion holes. By bringing the child into contact with an appropriate portion, it is possible to appropriately and easily evaluate the degree of adhesion of the bus bar of the power circuit section to the circuit arrangement surface and the thickness of the insulating layer.
[0011]
Specifically, the step of measuring the position of the circuit arrangement surface by inserting a contact for position measurement into the case side contactor insertion hole and bringing it into contact with the circuit arrangement surface of the heat radiating member, and the substrate Measuring the position of the upper surface of the busbar by inserting a contactor for position measurement into the side contactor insertion hole and bringing it into contact with the upper surface of the busbar. Based on the difference from the position of the bus bar, it is possible to determine whether the bus bar is adhered to the circuit arrangement surface.
[0012]
That is, the difference between the position of the circuit arrangement surface and the position of the upper surface of the bus bar indicates that the thickness of the insulating layer interposed between the circuit arrangement surface and the bus bar and the bus bar Since it should correspond to the sum of the thickness, it is possible to easily determine whether the bus bar is adhered to the circuit arrangement surface based on the difference.
[0013]
In this way, the degree of adhesion and the thickness of the insulating layer can be easily managed, so that it can contribute to quality improvement as well as cost reduction by eliminating the effort of quality control. .
[0014]
Each contact insertion hole may be a single one, but the board side contact insertion holes are provided at a plurality of locations on the circuit board, and case side contact insertion holes are provided at a plurality of locations on the case. Is more preferable. For this circuit component, the difference between the position of the upper surface of the bus bar measured at each board-side contactor insertion hole and the position of the busbar measured at the case-side contactor insertion hole closest to the board-side contactor insertion hole. By obtaining each of them and determining whether the bus bar is adhered to the circuit arrangement surface based on these differences, it is possible to perform a more appropriate inspection in consideration of variations in the adhesion state depending on the bonding location.
[0015]
The insulating layer may be formed, for example, by applying an adhesive on the circuit arrangement surface of the heat radiating member and curing it, and then reapplying the adhesive on the surface and overlaying the bus bar thereon. Good. According to this configuration, the heat radiation member and the bus bar can be bonded by the re-applied adhesive while maintaining reliable insulation by the insulating layer formed by the first application and curing. Even in this case, it is possible to appropriately evaluate the thickness of the entire insulating layer by the inspection method.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of a circuit structure and an inspection method thereof according to the present invention will be described with reference to the drawings. In addition, although the circuit structure which distributes the electric power supplied from the common power supply mounted in a vehicle etc. here to a plurality of electric loads is shown here, the use of the circuit structure according to the present invention is not limited to this, The present invention can be widely applied as a circuit structure having a heat dissipating member and required to be cooled.
[0017]
FIG. 1 is an exploded perspective view of a circuit structure according to the present embodiment. The circuit structure includes a power circuit unit 1 including a plurality of bus bars 10, a heat dissipation member 2 in which the power circuit unit 1 is disposed via an insulating layer 5, and protects the power circuit unit 1 from the outside. The case 3 is mounted on the heat radiating member 2 in a state where the seal member 4 is sandwiched between the case 3 and the heat radiating member.
[0018]
The power circuit unit 1 is formed by superimposing and bonding on the back surface (lower surface in the figure) of the control circuit board 13 in a state where a large number of bus bars 10 are arranged on a substantially flat surface. It is configured.
[0019]
The bus bar 10 includes an input bus bar connected to a power source and an output bus bar for outputting power to the outside, and a plurality of bus bars 10 are interposed between the input bus bar and the output bus bar. A switching element (for example, FET, LSI, thyristor, relay switch, etc.) 12 is mounted.
[0020]
A control circuit for controlling the switching operation of each switching element 12 is incorporated in the control circuit board 13, and each switching element 12 is mounted so as to be connected to both the control circuit and the power circuit. ing. Specifically, a control terminal (a gate terminal in the case of FET) of the switching element 12 is directly mounted on the control circuit board 13, and each switching element 12 is passed through a mounting through hole provided in the control circuit board 13. The current-carrying terminal (drain terminal or source terminal in the case of FET) is mounted on an appropriate bus bar 10.
[0021]
The portion of each bus bar 10 that protrudes outward from the control circuit board 13 is folded upward to form an external connection terminal 14. These external connection terminals 14 include, for example, an input terminal connected to a common in-vehicle power supply, an output terminal connected to the electronic unit, and a signal input terminal to which a control signal for controlling each switching element 12 is input. Etc. are included.
[0022]
The entire heat dissipating member 2 is integrally formed in a substantially rectangular shape in plan view using a material having excellent thermal conductivity such as aluminum metal. The upper surface is formed as a flat circuit arrangement surface 2a, and a plurality of radiating fins 20 arranged in the left-right direction protrude downward from the lower surface. The power circuit portion 1 is arranged on the circuit arrangement surface 2a via the insulating layer 5 (two insulating layers 5a and 5b in the illustrated example). The peripheral edge of the insulating layer protrudes.
[0023]
In order to form the insulating layer 5, for example, an adhesive (epoxy adhesive, silicone adhesive, etc.) having high insulation and thermal conductivity may be applied and cured, or the circuit arrangement surface 2a. You may make it stick an insulating sheet on it. In the present embodiment, the insulating layer 5 is formed by applying an adhesive made of an epoxy resin having excellent insulating properties and thermal conductivity.
[0024]
The heat radiation fin 20 can be omitted as appropriate, or a heat radiation pin or the like in which a heat radiation pin or the like protrudes on the side opposite to the circuit arrangement surface 2a may be used instead of the heat radiation fin 20. In addition, a thin groove or the like may be provided on the surface of the radiating fin, the radiating pin, etc. to increase the surface area and improve the radiating efficiency.
[0025]
The case 3 is made of an insulating material, and includes a case body 30 formed in a frame shape so as to surround the power circuit unit 1 as shown in FIGS. 1 and 2, and an opening formed in the center of the case body 30. The part 32 is finally closed by the lid 31.
[0026]
As shown in FIGS. 1, 2, and 4, the case main body 30 has a lower end surface extending along the peripheral edge of the circuit arrangement surface 2 a and a wall 33 extending downward from the peripheral edge of the wall 33. It has a skirt portion 34 covering the peripheral side surface of the member 2 and a resin sealing member 4 disposed on the lower end surface of the wall portion 33, and the circuit arrangement region of the power circuit portion 1, in other words, the heat radiating member 2. Can be surrounded.
[0027]
And the wall part 33 has the shape which surrounds the circuit arrangement | positioning area | region of the thermal radiation member 2, and as clearly shown in FIG. 4, it is inward from the front-end edge of the 1st vertical wall part 33a and the 1st vertical wall part 33a. A horizontal wall portion 33b that extends and a second vertical wall portion 33c that extends further upward (on the side opposite to the heat radiating member 2) from the front edge of the horizontal wall portion 33b, and extends over the entire circumference of the lower end surface of the first vertical wall portion 33a. Thus, a sealing material filling groove 35 is formed. That is, the sealing material filling groove 35 is provided so as to surround the circuit arrangement region of the circuit arrangement surface 2a, and is filled with the resin sealing material 4. The cross section of the sealing material filling groove 35 is not particularly limited, but is formed in a substantially U-shaped cross section in the present embodiment.
[0028]
Further, the wall 33 is set such that the peripheral side wall height is at least higher than the leg-shaped terminals 12a of the switching element 12 mounted on the power circuit unit 1, and preferably higher than the heights of these various electronic components 12. Highly formed. That is, the wall portion 33 is formed so as to surround the power circuit portion 1 including various electronic components (the switching element 12 in the present embodiment). In the present embodiment, the wall 33 is set to have a peripheral wall height higher than that of the switching element 12.
[0029]
The opening 32 is formed in a shape that opens almost the entire area of the control circuit board 13 in the power circuit portion 1 upward, and the power circuit portion is passed through the opening 32 even after the case body 30 is attached to the heat radiating member 2. 1 can be pressed from above to the circuit arrangement surface 2a of the heat dissipating member 2 to make the bonding with the adhesive more reliable.
[0030]
The wall 33 is formed with a plurality of connector housings 36 integrally therewith. Each connector housing 36 includes a bottom portion having a terminal through-hole 37 through which the external connection terminal 14 of the power circuit unit 1 is inserted, and a plurality of pieces projecting to the opposite side of the circuit arrangement surface 2 a through the terminal through-hole 37. A hood 38 that surrounds the external connection terminals 14 is formed, and together with these external connection terminals 14, an external connection connector that can be coupled to an external connector (for example, a connector attached to the end of a cable) is configured. In the present embodiment, the bottom of the connector housing 36 is constituted by a horizontal wall portion 33b.
[0031]
In the connector housing 36 according to this embodiment, as shown in FIGS. 3 and 4, the bottom surface of the connector housing 36 leaves a connector abutting surface 36a on which the front end surface of another connector abuts. A resin reservoir recess 39 is formed so as to be recessed below 36a (the heat radiating member 2 side), and a terminal through hole 37 is provided in the region where the resin reservoir recess 39 is formed. In some of the connector housings 36, as shown in FIGS. 3 and 4, a resin insertion hole that communicates from the resin reservoir recess 39 to the inside of the wall 33, specifically, to the lower side of the horizontal wall 33b. 40 is provided.
[0032]
The resin reservoir recess 39 is provided for introducing and filling a waterproof resin, which will be described later, through the terminal through-hole 37, and a waterproof layer 6 described later is formed in the resin reservoir recess 39. It is provided in order to prevent the ingress of water through the terminal through-hole 37 and effectively prevent a short circuit of the power circuit unit 1. It is assumed that the reservoir recess 39 overflows. On the other hand, the resin insertion hole 40 assists and strengthens the introduction of the waterproof resin from the terminal through hole 37, and the waterproof resin is introduced into the resin reservoir recess 39 through the resin insertion hole 40.
[0033]
In the illustrated example, the connector housing 36 is formed such that a portion located at the lower end portion bulges outwardly in a state where the entire circuit structure is placed vertically, and the connector housing 36 is located within the bulging portion 36b. The horizontal wall 33b is provided with a drain hole 36c that opens to the heat radiating member 2 side and to the outside of the resin sealing material 4. The drain hole 36 c is for discharging water accumulated in the connector housing 36, and the water discharged from the drain hole 36 c is a drainage passage 50 between the heat radiating member 2 and the case body 30. It is supposed to be discharged to the outside.
[0034]
The second vertical wall 33c has a drainage notch 51 in the lower part when the circuit structure is placed vertically, and the drainage notch 51 is opposed to the surface of the waterproof layer 6 described later. Alternatively, it is provided above the surface of the waterproof layer 6. Further, on the lower surface of the horizontal wall portion 33b, there is a pressing projection 52 for pressing the bus bar 10 constituting the external connection terminal 14.
[0035]
On the other hand, the skirt portion 34 has a frame shape covering the four side surfaces of the heat radiating member 2, and a pair of opposing side walls are formed in a jagged shape corresponding to the shape of the heat radiating fins 20. In addition, a locking claw 53 that locks to a corresponding portion of the heat radiating member 2 is formed at an appropriate position of the skirt portion 34 so that the case main body 30 and the heat radiating member 2 can be firmly assembled.
[0036]
The lid 31 has a plate shape corresponding to the opening 32 of the case body 30 and is attached to the case body 30 by a locking structure (not shown) or attached to the case body 30 by adhesion, welding, or the like. The lid 31 can be omitted as appropriate, but the power circuit unit 1 is more reliably protected by the attachment.
[0037]
The resin sealing material 4 is formed in an annular shape surrounding the circuit arrangement region, and can be closely fitted in the sealing material filling groove 35. The resin sealing material 4 temporarily prevents the waterproof resin from leaking out from the case body 30 until the later-described liquid waterproof resin is injected into the inner region until the waterproof resin is cured. For example, closed-cell foamed rubber is suitable.
[0038]
Further, as a feature of this circuit structure, as shown in FIGS. 6 and 7A and 7B, it is arranged in the plate thickness direction at a plurality of locations (three locations in the example of FIG. 6) of the control circuit board 13. The board side contact insertion holes 13h, 13i, and 13j that penetrate therethrough are provided, and the case side contact that penetrates the upper wall portion in a plurality of places (three places in the example of FIG. 6) of the case wall 33 in the wall thickness direction. Child insertion holes 33h, 33i, and 33j are provided.
[0039]
The case side contactor insertion holes 33h, 33i, and 33j are provided at positions where the edges of the circuit arrangement surface 2a, that is, the portions where the insulating layer 5 is formed are opened upward. As shown in FIG. 7A, the position measuring contact 60 is inserted into the contact insertion holes 33h, 33i, 33j so that the tip of the contact 60 is directly on the circuit arrangement surface 2a (that is, the insulating layer). Without intervening 5).
[0040]
On the other hand, the board side contactor insertion holes 13h, 13i, 13j are provided in a portion of the control circuit board 13 where the bus bar 10 is disposed on the back side, and these boardside contactor insertion holes 13h, 13i. , 13j, as shown in FIG. 7B, the position measuring contact 60 is inserted so that the tip of the contact 60 is superposed on the upper surface of the bus bar 10 (that is, the back surface of the control circuit board 13). ) Can be contacted.
[0041]
Next, the manufacturing process of this circuit structure and the inspection method of the adhesion site will be described.
[0042]
1) Parts manufacturing process
The power circuit unit 1, the heat radiating member 2, and the case body 30 are manufactured separately. In the case body 30, the resin sealing material 4 is loaded in the sealing material filling groove 35, and the power circuit unit 1 is assembled to the case body 30 by inserting the external connection terminal 14 into the terminal through hole 37. . Thus, by assembling the power circuit unit 1 in the case body 30 in advance, the alignment of the external connection terminal 14 with respect to the terminal through hole 32 can be ensured.
[0043]
2) Adhesion process
The case main body 30 assembled with the power circuit unit 1 is attached to the heat radiating member 2 in a state where an adhesive for constituting the insulating layer 5 is applied to the circuit arrangement region of the heat radiating member 2. As a result, the bus bar 10 of the power circuit unit 1 comes into contact with the adhesive and is joined to the circuit arrangement region on the circuit arrangement surface 2 a of the heat radiating member 2.
[0044]
Furthermore, an appropriate location (multiple locations) of the control circuit board 13 in the power circuit unit 1 is pressed through the opening 32 of the case body 30, and the (insulating layer 5) between the power circuit unit 1 and the circuit arrangement surface 2 a is pressed. To improve adhesion). Specifically, an appropriate place of the power circuit unit 1, particularly a peripheral part of the power circuit unit 1 and a peripheral part of the switching element 12 are pressed through the opening 32 of the case body 30 to place the power circuit unit 1 on the circuit of the heat radiating member 2. Bond firmly to the area. In this way, by pressing the power circuit unit 1 and joining it to the heat radiating member 2, the bus bar 10 located on the back surface of the power circuit unit 1 is buried in the adhesive, and the insulation between the bus bars 10 is provided by the adhesive. While short circuit is prevented reliably, the thermal conductivity between the power circuit unit 1 and the heat radiating member 2 can be improved. Thereafter, the adhesive is cured by heating to form a complete insulating layer 5.
[0045]
In this step, the case main body 30 is attached to the heat radiating member 2 by locking the locking claw 53 of the skirt portion 34 to the corresponding position of the heat radiating member 2. It may be attached by a mechanical fixing member such as a bolt, or may be attached by adhesion or the like, and a known attachment method is adopted. Moreover, when using what has adhesiveness as waterproofing resin mentioned later, this case main body 5 may be attached to the heat radiating member 2 by temporary fixing.
[0046]
On the other hand, the insulating layer 5 can be formed only by applying the adhesive once. For example, in the first application, the adhesive is cured as it is without bonding the power circuit portion 1, and FIG. The lower insulating layer 5a as shown in (b) is formed, the same kind of adhesive or different kinds of adhesive is applied on the lower insulating layer 5a, and the power circuit portion 1 is adhered with the adhesive, and then the adhesive. The upper insulating layer 5b may be formed by curing. In this way, higher insulation reliability can be obtained by forming the lower insulating layer 5a in advance before bonding. For example, even when a pinhole is generated at the time of forming the insulating layer 5a, for example, an adhesive applied on the insulating layer 5a fills the pinhole so that the insulation between the power circuit unit 1 and the heat dissipation member 2 is more reliable Become.
[0047]
As the adhesive constituting the insulating layer 5, for example, an adhesive made of an epoxy resin is suitable, but other adhesives can be applied as long as the adhesive has good thermal conductivity.
[0048]
Through the above steps, the power circuit portion 1 is disposed in the circuit disposition region on the circuit disposition surface 2a of the heat dissipating member 2, and the circuit disposition of the heat dissipating member 2 including the power circuit portion 1 by the case main body 30. A surrounding wall is formed surrounding the circuit arrangement region on the surface 2a. This surrounding wall functions as a dam for waterproofing resin used when a waterproofing process described later is performed.
[0049]
3) Inspection process
In this step, the adhesion between the circuit arrangement surface 2 and the bus bar 10 after the bonding step and the appropriateness of the thickness of the insulating layer 5 interposed therebetween are inspected.
[0050]
First, as shown in FIG. 7A, the entire circuit component is placed on the reference surface S with the heat dissipating member 2 facing downward, and is placed in the case side contactor insertion holes 33h, 33i, 33j. Sequentially, a pin-shaped position measuring contact 60 is inserted from above, and its tip is brought into direct contact with the circuit arrangement surface 2a (that is, without interposing the insulating layer 5). From the height position of the position measuring contact 60 at this time, the height position (from the reference surface S) of the circuit arrangement surface 2a at the place where each case side contactor insertion hole 33h, 33i, 33j is provided. The height direction distance) H1 is determined and stored.
[0051]
Next, as shown in FIG. 5B, the pin-shaped position measuring contacts 60 are sequentially inserted into the board-side contact insertion holes 13h, 13i, 13j from above, and their tips are inserted into the bus bar 10. Is brought into contact with the upper surface (the surface on the side facing the control circuit board 13). From the height position of the position measuring contact 60 at this time, the height position (the height from the reference surface S) of the upper surface of the bus bar 10 at the location where the board side contact insertion holes 13h, 13i, 13j are provided. The distance in the vertical direction) H2 is determined and stored.
[0052]
Thereafter, the height position H2 obtained for each of the board-side contactor insertion holes 13h, 13i, and 13j and the case-side contactor insertion holes 33h and 33i that are closest to the board-side contactor insertion holes 13h, 13i, and 13j, respectively. , 33j, the difference from the height position H1 obtained is calculated. This difference (H2−H1) should correspond to the sum of the thickness of the bus bar 10 and the thickness of the insulating layer 5 when the bus bar 10 and the circuit arrangement surface 2 are completely adhered via the insulating layer 5. Therefore, based on the calculated value of the difference, the adhesion state between the circuit arrangement surface 2a and the bus bar 10 can be evaluated easily and appropriately.
[0053]
In the present invention, the specific numbers of the case side contactor insertion holes and the substrate side contactor insertion holes are not limited, and the number of these insertion holes is not necessarily the same. However, as shown in this embodiment, if information regarding the height position of the circuit arrangement surface and the height position of the upper surface of the bus bar is collected at a plurality of locations, it is possible to evaluate a more appropriate adhesion state.
[0054]
After the inspection process is completed, waterproofing may be performed as appropriate. In this embodiment, it is effective to form a waterproof layer 6 by filling a predetermined amount of liquid waterproof resin in the space surrounded by the case body 30 and curing the waterproof resin.
[0055]
Specifically, liquid waterproof resin is injected from the opening 32 of the case body 30 with the circuit arrangement surface 2a facing upward, and various electronic components (switching elements 12) mounted on the power circuit unit 1 are injected. ) To a sealing height. At this time, the waterproof resin overflows into the connector housing 36 through the terminal through holes 37 and the resin insertion holes 40 and reaches a predetermined height in the resin reservoir recess 39.
[0056]
In a state where the waterproof resin is filled, the bus bar constituting plate 11 and the control circuit board 13 including the base end portion of the external connection terminal 14 are also immersed in the waterproof resin. On the other hand, since the circuit arrangement region is surrounded by the resin sealing material 4, even if it is a liquid waterproof resin, it does not leak from the gap between the heat radiating member 2 and the case body 30.
[0057]
The waterproof resin may be waterproof as long as the material is not particularly limited. However, by using a liquid resin as in the present embodiment, the waterproof resin can be applied to every corner of the case body 5. It can be spread and sealed reliably. In addition, it is preferable to use a waterproof resin having a certain elasticity and shape retention even after curing because it has little influence on the switching element 12 and solder. Furthermore, it is preferable to use a silicone resin or the like from the viewpoint of not only excellent heat resistance and cold resistance, but also good electrical insulation. Further, if a resin having adhesiveness is employed as the waterproof resin, the work of applying a primer or the like can be omitted and the work can be simplified. Furthermore, if a resin having excellent thermal conductivity is adopted as the waterproof resin, not only heat dissipation by the heat radiating member 2 is promoted, but also heat is radiated from the waterproof layer 6 to have better heat dissipation. Can do.
[0058]
And the waterproofing resin with which it filled is heat-hardened, and the waterproof layer 6 is formed. Thus, the waterproof layer 6 seals at least a part of the power circuit portion and the terminal through hole inside the case main body. Next, after manufacturing the lid 7 that covers the opening 32 of the case body 30 and forming the waterproof layer 6, the lid 7 is attached to the case body 30 in a state of covering the opening 32.
[0059]
The formation of the waterproof layer 6 is not necessarily required. Instead of the formation of the waterproof layer 6, for example, a waterproof treatment may be provided by a combination of a sealing material and the lid 31.
[0060]
【The invention's effect】
As described above, according to the present invention, the power circuit portion provided on the circuit arrangement surface of the heat radiating member is configured by being overlaid on the circuit board with a plurality of bus bars arranged on a substantially plane. Thus, the thickness can be reduced, and the circuit arrangement portion can be protected from the outside by the case attached to the heat dissipation member.
[0061]
A step of measuring the position of the circuit arrangement surface by inserting a contact for position measurement into the case side contactor insertion hole and bringing it into contact with the circuit arrangement surface of the heat radiating member; and the substrate side contactor The step of measuring the top surface position of the bus bar by inserting a contact for position measurement into the insertion hole and bringing it into contact with the bus bar makes it possible to determine the position of the measured circuit arrangement surface and the top surface position of the bus bar. Based on the difference, it is possible to easily and properly determine whether the bus bar is adhered to the circuit arrangement surface, and this inspection can guarantee high insulation reliability and circuit arrangement portion cooling performance. .
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a circuit structure according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view of a case body, a resin sealing material, and a heat radiating member in the circuit configuration body as viewed from the heat radiating member side.
FIG. 3 is a partially enlarged view of a case body in the circuit configuration body.
4 is a sectional view taken along line VI-VI in FIG. 3;
FIG. 5 is a perspective view showing the switching element in a state where the leg terminals are sealed with a waterproof resin.
FIG. 6 is a plan view of the circuit configuration body.
7A and 7B are cross-sectional front views showing an inspection process of the circuit structure.
[Explanation of symbols]
1 Power circuit section
2 Heat dissipation member
2a Circuit layout surface
3 cases
5 Insulation layer
5a Lower insulating layer
5b Upper insulating layer
10 Busbar
12 Switching element
13 Control circuit board
13h, 13i, 13j Substrate side contact insertion hole
30 Case body
33 Wall
33h, 33i, 33j Case side contact hole
60 Contactor for position measurement

Claims (5)

A heat dissipation circuit having a power circuit portion configured by overlapping a plurality of bus bars on a circuit board in a state of being arranged on a substantially plane, and a circuit arrangement surface on which the bus bars of the power circuit portion are bonded via an insulating layer A member, and a case that is attached to the heat radiating member so as to protect the circuit arrangement portion from the outside, and that has an opening for exposing at least a part of the circuit arrangement surface to the outside in the attached state. In this case, there is a case-side contact insertion hole for contacting the contact for position measurement with the surface of the area where the power circuit portion and the insulating layer are not provided in the circuit arrangement surface. A circuit board side contact insertion hole is provided in a portion of the circuit board of the power circuit section that is exposed to the outside through the opening of the case. Circuit component, characterized by being. 2. The circuit structure according to claim 1, wherein the board-side contact insertion holes are provided at a plurality of locations in the circuit board, and the case-side contact insertion holes are provided at a plurality of locations of the case. A circuit structure. 3. The circuit structure according to claim 1, wherein the insulating layer is formed by applying an adhesive on the circuit arrangement surface of the heat radiating member and curing the adhesive, and then reapplying the adhesive thereon. A circuit structure characterized in that it is formed by superimposing layers. It is a method to test | inspect the circuit structure of any one of Claims 1-3, Comprising: The contact for position measurement is inserted in the said case side contactor insertion hole, and it is on the circuit arrangement | positioning surface of a heat radiating member. A step of measuring the position of the circuit arrangement surface by contacting, and a position measuring contact is inserted into the board-side contact insertion hole to contact the upper surface of the bus bar to thereby adjust the position of the upper surface of the bus bar. A circuit component comprising: a step of measuring, and determining whether the bus bar is adhered to the circuit arrangement surface based on a difference between the measured position of the circuit arrangement surface and the position of the bus bar Inspection method. 3. A method for inspecting a circuit structure according to claim 2, wherein a contact for measuring position is inserted into each case side contact insertion hole and brought into contact with a circuit arrangement surface of a heat radiating member. A step of measuring the position of the installation surface, and a step of measuring the position of the upper surface of the bus bar by inserting a contact for position measurement into each substrate side contactor insertion hole and bringing it into contact with the upper surface of the bus bar. Determining the difference between the position of the upper surface of the bus bar measured at each board side contact hole and the position of the bus bar measured at the case side contact hole closest to the board side contact hole. And determining whether or not the bus bar is adhered to the circuit arrangement surface based on the test method.

Images