JP2019067865A - Circuit board, connection structure of conductive member and electric compressor - Google Patents

Abstract

To increase the flexibility of connection of a conductive member with respect to a metallic circuit board.SOLUTION: A board 1 comprises a peripheral portion 22 where an electric circuit is formed, an isolation portion 21 to which a terminal 40 is fixed, and an insulating portion 30 that is interposed between a first side surface portion 22S and a second side surface portion 21S and couples the isolation portion 21 to the peripheral portion 22 and electrically insulates the isolation portion 21 from the peripheral portion 22. The first side surface portion 22S is joined to the insulating portion 30, and includes a first outer peripheral surface 21a, a second outer peripheral surface 21b and a third outer peripheral surface 21c each subjected to alumite treatment to increase bonding strength with the insulating portion 30. The second side surface portion 21S is joined to the insulating portion 30, and includes a first inner peripheral surface 22a, a second inner peripheral surface 22b, and a third inner peripheral surface 22c each subjected to an alumite treatment for enhancing the bonding strength with the insulating portion 30.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a circuit board, a connecting structure of conductive members including the circuit board, and an electric compressor including the connecting structure of conductive members.

  Patent Document 1 discloses a connection structure in which a terminal is connected to a copper pattern on an aluminum substrate. In this connection structure, the terminals are fixed to the copper pattern by soldering. The copper pattern has an H-shaped electrode pattern. This electrode pattern is soldered to the terminal.

Japanese Utility Model Application Publication No. 5-79974

  Since a metal substrate such as aluminum is excellent in heat dissipation, it can be adopted as an inverter or converter for large current. For example, a circuit made of copper foil or the like is formed on the front surface side of the substrate, and a base substrate is provided on the back surface side of the substrate. When an external circuit is electrically connected to the circuit, a conductive member (for example, a terminal) is used. The conductive member is soldered to the surface of the substrate as disclosed in Patent Document 1 above.

  Generally, the size of the conductive member through which a large current flows is large. In addition, a large amount of heat is required for soldering to a base substrate with good heat dissipation. Furthermore, for example, when a semiconductor element such as a MOSFET (Metal-Oxide-semiconductor field-effect transistor) is mounted near the conductive member, the semiconductor element may be damaged by heat for soldering. Thus, soldering is a connection method with some limitations.

  An object of the present invention is to provide a circuit board in which the degree of freedom of connection of a conductive member to a metal circuit board is increased, a connection structure of a conductive member including a circuit board, and an electric compressor including a connection structure of conductive members. I assume.

  The circuit board according to an aspect of the present invention is a metal plate having a first side surface portion, and is a metal plate having a first substrate portion on which an electric circuit is formed and a second side surface portion, and is connected to the electric circuit. And a first side surface portion and a second side surface portion to connect the second substrate portion to the one substrate portion and the second substrate portion to the first substrate portion. And the first side surface portion includes a first treated surface joined to the insulating portion and treated to increase the bonding strength with the insulating portion, The second side surface portion is joined to the insulating portion and includes a second treated surface treated to increase the bonding strength with the insulating portion.

  The second substrate unit is connected to be electrically insulated from the first substrate unit. Here, first and second treated surfaces are respectively formed on the first and second side wall surfaces to which the insulating portion is joined. The first and second treated surfaces are treated to increase the bonding strength to the insulating portion. Then, the insulating portion is firmly bonded to the first and second substrate portions, and hence the second substrate portion can be reliably connected to the first substrate portion. According to this configuration, the bonding portion between the first and second substrate portions and the insulating portion can resist the external force acting on the first and second substrate portions. Therefore, the connection state of the first and second substrate parts can be maintained. Thereby, when fixing a conductive member with respect to a 2nd board | substrate part, it becomes possible to employ | adopt mechanical structure using a volt | bolt etc. FIG. Therefore, since the restriction | limiting with above-described prior art (for example, soldering connection structure) is relieved, the freedom degree of the connection of the electrically-conductive member with respect to a metal circuit board can be raised.

  In one form, the first treated surface and the second treated surface may be surfaces that have been subjected to surface treatment or modification treatment to increase the bonding strength with the insulating portion. According to this configuration, the first processing surface can be suitably formed.

  In one form, the first substrate portion and the second substrate portion are formed of aluminum, the first side surface portion and the second side surface portion include an alumite film, and the first treated surface and the second treated surface are an alumite film. It may be a surface. An alumite film has good bondability to a resin material. Therefore, the bonding strength of the bonding portion between the first and second substrate portions and the insulating portion can be surely enhanced.

  In one form, the second substrate portion may have a through hole through which a fixing member for fixing the conductive member is inserted. According to this configuration, the conductive member can be fixed to the second substrate portion by using a fixing member such as a bolt. Therefore, the conductive member can be reliably fixed to the circuit board.

  In one form, the first substrate portion further includes a third side surface portion not bonded to the insulating portion, and the second substrate portion further includes a fourth side surface portion not bonded to the insulating portion, and the insulating portion The semiconductor device may further include a fifth side surface portion not bonded to the substrate portion and the second substrate portion, and the third side surface portion, the fourth side surface portion, and the fifth side surface portion may be included in the substrate end surface. According to this configuration, the second substrate unit is disposed at the side or corner of the circuit board. Therefore, the second substrate part surrounded by the first substrate part and the insulating part can be easily formed.

  A connection structure of a conductive member according to another aspect of the present invention includes the above circuit board, a conductive member fixed to the circuit board, and a fixing member fixing the conductive member to the circuit board, The circuit board includes a plate-like base plate including a first substrate, a second substrate, and an insulator, an insulating layer formed on the surface of the base, and a conductive pattern formed on the surface of the insulator. And the circuit board has a through hole which penetrates the conductive member, the insulating part and the second substrate in the thickness direction and is inserted into the hole of the conductive member, and the fixing member passes through the circuit board A shaft portion inserted into the hole and the hole portion of the conductive member, a first end provided at one end of the shaft portion to press the conductive member in the thickness direction, and a second substrate portion provided at the other end of the shaft portion And a second end pressing in the thickness direction.

  The circuit board has a through hole penetrating the conductive pattern portion, the insulating layer portion, and the second substrate portion in the thickness direction. The shaft of the fixing member is inserted into the through hole and the hole of the conductive member. The first end provided at both ends of the shaft portion is engaged with the conductive member, and the second end is engaged with the circuit board (more specifically, with the second board portion), whereby the conductive member is engaged with the circuit board It is fixed against. The second substrate portion is electrically insulated from the first substrate portion by the insulating portion. Therefore, the first substrate portion is electrically insulated from the conductive member, the fixing member, and the second substrate portion, and the first substrate portion does not short circuit to the conductive member. According to the structure in which the conductive member is fixed to the circuit board using the through hole and the fixing member, the limitations associated with the above-described prior art (for example, the solder connection structure) are alleviated. Thus, the degree of freedom in connection of the conductive member to the metal circuit board can be increased.

  According to still another aspect of the present invention, there is provided an electric compressor including the above-described circuit board, and a motor in which the conductive member is electrically connected to the circuit board by the connection structure of the conductive member, and a compressor connected to the motor And. In this case, it is possible to increase the degree of freedom in connection of the conductive members even in the case of a motor-driven compressor to which a large current can flow.

  According to some aspects of the present invention, the degree of freedom in connection of the conductive member to the metal circuit board is increased.

FIG. 1 is an exploded perspective view showing a connection structure according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a connection structure according to an embodiment of the present invention. FIG. 3 is a bottom view showing the circuit board of FIG. FIG. 4 is an exploded perspective view showing the configuration of the base substrate. FIG. 5 is an enlarged perspective view showing the vicinity of the end face of the insulating portion. Parts (a), (b) and (c) of FIG. 6 are perspective views showing main steps of forming the connection structure of FIG. Parts (a), (b) and (c) of FIG. 7 are perspective views showing the main steps of forming the connection structure of FIG. FIG. 8 is a schematic view showing an example in which the connection structure of FIG. 1 is applied to an electric compressor. FIG. 9 is a cross-sectional view showing a connection structure according to a comparative example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols and redundant description will be omitted.

  The connection structure 100 of the present embodiment will be described with reference to FIG. The connection structure 100 electrically connects a terminal (conductive member) 40 to the substrate 1 (circuit board). The substrate 1 is a metal substrate called a so-called metal substrate, and is, for example, a power substrate (main circuit substrate) through which a large current flows. The terminal 40 connected to the substrate 1 is a terminal for flowing a large current. Terminal 40 may be, for example, a bus bar or the like.

  The terminal 40 includes a flat connection portion 41 connected to the substrate 1 and a lead-out portion 42 provided continuously to the connection portion 41. The terminal 40 is, for example, an L-shaped component, but the shape of the terminal 40 is not limited to the L-shape. The lead portion 42 of the terminal 40 is connected to, for example, a power supply.

  A plurality of terminals 40 may be connected to the substrate 1. One or more connection structures 100 are provided on the substrate end face 1 c of the substrate 1. The connection structure 100 may be provided at the corner of the substrate 1. The substrate 1 having a rectangular shape as a whole has edge portions such as a substrate end surface 1 c and corner portions. The connection structure 100 is provided at these end edges. The edge means an edge in a direction orthogonal to the thickness direction of the substrate 1. The connection structure 100 may be provided in a portion other than the edge portion of the substrate 1, for example, in the central portion.

  The substrate 1 includes a surface 1 a which is a surface to which the terminal 40 is connected, and a back surface 1 b opposite to the surface 1 a. The substrate 1 has a metal base substrate 3 (base plate portion) on the back surface 1 b side. Thus, the heat dissipation of the substrate 1 is enhanced. The back surface 1 b of the substrate 1 may be connected to a cooling unit (not shown) in a region excluding the separation unit 21 described later.

  The substrate 1 includes a conductive pattern 2 (conductive pattern portion) disposed on the front surface 1 a side, a metal base substrate 3 (base plate portion) disposed on the back surface 1 b side, and the conductive pattern 2 and the base substrate 3. And an insulating layer 4 (insulating layer portion) disposed therebetween. The base substrate 3, the insulating layer 4 and the conductive pattern 2 are stacked in this order and bonded to each other. Conductive pattern 2 includes a front surface 2a corresponding to front surface 1a, and a back surface 2b opposite to front surface 2a. Base substrate 3 includes a back surface 3 b corresponding to back surface 1 b and a front surface 3 a opposite to back surface 3 b. Insulating layer 4 includes a front surface 4 a facing back surface 2 b of conductive pattern 2, and a back surface 4 b opposite to front surface 3 a of base substrate 3 opposite to front surface 4 a. The back surface 2 b of the conductive pattern 2 and the surface 4 a of the insulating layer 4 are in flat contact with each other. The front surface 3a of the base substrate 3 and the back surface 4b of the insulating layer 4 are in flat contact with each other.

  Conductive pattern 2 is, for example, a metal foil. Conductive pattern 2 may be, for example, a copper foil or the like. The conductive pattern 2 forms an electrical circuit to which the terminal 40 is electrically connected.

  Base substrate 3 is a substrate made of, for example, aluminum. The base substrate 3 is attached to, for example, an apparatus to which the connection structure 100 is applied. The base substrate 3 is a cooling unit that dissipates heat generated by an inverter, a converter, or the like. The base substrate 3 may be connected to cooling means (not shown). The base substrate 3 may be made of iron or copper.

  Insulating layer 4 is made of, for example, a thermosetting resin. Insulating layer 4 may be made of, for example, an epoxy resin. The insulating layer 4 insulates the base substrate 3 from the conductive pattern 2. As a material which constitutes insulating layer 4, other publicly known insulating materials may be used.

  The connection structure 100 includes a fastening member 10 (fixing member) for fixing the terminal 40 to the substrate 1. In the present embodiment, the bolt 13 and the nut 14 are used as the fastening member 10. Hereinafter, the fixing structure using the fastening member 10 will be described in detail.

  As shown in FIG. 2, in the substrate 1, a through hole 5 penetrating in the thickness direction is formed. The through holes 5 are through holes penetrating the conductive pattern 2, the insulating layer 4, and the base substrate 3 in the thickness direction. More specifically, in the conductive pattern 2, for example, a cylindrical hole 2c is formed. In the insulating layer 4, for example, a cylindrical hole 4 c is formed. For example, a cylindrical hole 3 c is formed in the base substrate 3. The hole 2c, the hole 4c, and the hole 3c communicate with each other. The through hole 5 of the substrate 1 is formed by combining the hole 2 c, the hole 4 c, and the hole 3 c.

  The axes of the hole 2c, the hole 4c, and the hole 3c may coincide with each other. That is, the hole 2c, the hole 4c, and the hole 3c may be formed concentrically with respect to one axis. The diameters of the hole 2c, the hole 4c, and the hole 3c may be equal.

  On the other hand, in the connection portion 41 of the terminal 40, for example, a cylindrical hole portion 41c is formed. The connection portion 41 is superimposed on the surface 2 a of the conductive pattern 2 and is in contact with the circuit described above. The hole 41 c communicates with the through hole 5.

  The shaft 12 of the bolt 13 of the fastening member 10 is inserted through the hole 41 c of the terminal 40 and the through hole 5 of the substrate 1. The shaft portion 12 includes a first end disposed in the hole portion 41 c and a second end protruding from the back surface 1 b side of the through hole 5. The bolt 13 includes a head 11 provided at a first end of the shank 12. The diameter of the head 11 (the width in the direction perpendicular to the axis of the shaft 12) is larger than the diameter of the hole 41c, for example, larger than the diameter of the through hole 5. The head 11 is locked on the connection portion 41. The head 11 may have a hexagonal shape that allows the rotary tool to be fitted. It is sufficient if a predetermined rotary tool can be fitted to the head 11. The shape of the head 11 is not limited. For example, the shape of the head 11 may be dish-like.

  The nut 14 is provided at the second end of the shaft 12. The diameter of the nut 14 (the width in the direction perpendicular to the axis of the shaft 12) is larger than the diameter of the through hole 5, for example, larger than the diameter of the hole 41c. The nut 14 is locked on the back surface 3 b of the base substrate 3.

  In the connection structure 100, the connection portion 41 of the terminal 40 is fixed to the substrate 1 by screwing the bolt 13 into the nut 14. The nut 14 disposed on the back surface 1 b side of the substrate 1 may be fixed to, for example, the back surface 3 b of the base substrate 3. The nut 14 may be accommodated in a recess of a member separate from the substrate 1. In this case, the nut 14 may be a floating nut. The nut 14 is not limited to a hexagonal shape, and may be a square. If a configuration in which the nut 14 does not need to be gripped with a tool or the like is adopted, the workability of tightening can be ensured even when the space on the back surface 1 b side of the substrate 1 is limited, for example.

  The head 11 of the bolt 13 is pressed (contacted) to the connecting portion 41 by the fastening force of the fastening member 10, and the nut 14 is pressed (contacted) to the base substrate 3. The substrate 1 and the connection portion 41 are sandwiched and fixed by the head 11 and the nut 14.

  As shown in FIG. 3, the nut 14 of the fastening member 10 is within the range of the separating portion 21 described later. The nut 14 may be within the range of the insulating portion 30 and the separating portion 21 described later. That is, the size of the nut 14 and the sizes of the separating part 21 and the insulating part 30 are set so that the nut 14 does not contact the peripheral part 22. In other words, the circumscribed circle of the nut 14 (the circle passing through each vertex) may be within the range of the insulating portion 30 and the separating portion 21. It is preferable that the circumscribed circle of the nut 14 does not extend beyond the insulating portion 30. The circumscribed circle of the nut 14 may be positioned inside the inner circumferential surface 32S of the insulating portion 30, or may intersect the inner circumferential surface 32S, but does not intersect the outer circumferential surface 31S of the insulating portion 30.

  As shown in FIG. 4, the base substrate 3 includes the isolation portion 21 (second substrate portion) surrounding the hole portion 3 c constituting the through hole 5, the insulating portion 30 surrounding the isolation portion 21, the isolation portion 21 and the insulation And a peripheral portion 22 (first substrate portion) surrounding the portion 30. The isolation portion 21 and the peripheral portion 22 are, for example, metal plates made of the same material (aluminum alloy) and have the same thickness. The isolation portion 21 has, for example, a rectangular shape (see FIG. 3). The peripheral portion 22 may be connected to cooling means (not shown).

  The isolation portion 21 is a rectangular flat plate, and includes a front surface 21t, a back surface 21u, a second side surface portion 21S, and a fourth side surface portion 21T. The surface 21 t is included in the surface 3 a of the base substrate 3 and is in contact with the insulating layer 4. The back surface 21 u is a surface opposite to the front surface 21 t and is included in the back surface 3 b of the base substrate 3. Moreover, the isolation part 21 has a hole 3 c penetrating from the front surface 21 t to the back surface 21 u. The second side surface portion 21S has a first outer peripheral surface 21a, a second outer peripheral surface 21b, and a third outer peripheral surface 21c. The first outer peripheral surface 21a, the second outer peripheral surface 21b, and the third outer peripheral surface 21c face the peripheral portion 22 with the insulating portion 30 described later interposed therebetween. On the other hand, the fourth outer peripheral surface 21 d which is the fourth side surface 21 T does not face the peripheral portion 22. That is, the fourth outer peripheral surface 21d is included in the substrate end surface 1c (see FIG. 1).

  The peripheral portion 22 is a base of the base substrate 3 and has a large area compared to the isolation portion 21. The peripheral portion 22 includes a front surface 22t, a back surface 22u, a first side surface portion 22S, and a third side surface portion 22T. Furthermore, the peripheral portion 22 has a notch S penetrating from the front surface 22t to the back surface 22u and opening in the substrate end face 1c. In the notch portion S having a rectangular shape in plan view, the separation portion 21 and the insulating portion 30 are disposed. The surface 22 t is included in the surface 3 a of the base substrate 3 and is in contact with the insulating layer 4. The back surface 22 u is a surface opposite to the front surface 22 t and is included in the back surface 3 b of the base substrate 3. The first side surface portion 22S includes a first inner circumferential surface 22a, a second inner circumferential surface 22b, and a third inner circumferential surface 22c. The notch S is a region surrounded by the first inner peripheral surface 22a, the second inner peripheral surface 22b, and the third inner peripheral surface 22c. The first inner circumferential surface 22 a faces the first outer circumferential surface 21 a of the separating portion 21 with the insulating portion 30 described later interposed therebetween. The second inner circumferential surface 22 b faces the second outer circumferential surface 21 b of the separating portion 21 with the insulating portion 30 interposed therebetween. The third inner circumferential surface 22 c faces the third outer circumferential surface 21 c of the separating portion 21 with the insulating portion 30 interposed therebetween. On the other hand, the fourth outer peripheral surface 22 d which is the third side surface portion 22 T does not face the separating portion 21. That is, the fourth outer peripheral surface 22d is included in the substrate end surface 1c.

  Here, as illustrated in FIG. 5, the separation unit 21 includes a base 21 </ b> M and an alumite film 21 </ b> R formed on the base 21 </ b> M. The alumite film 21R is a layer obtained by the process of enhancing the bonding strength with the insulating portion 30. The treatment for increasing the bonding strength can be said to be, for example, a surface treatment or modification treatment for increasing the bonding strength. That is, the surface 21t, the back surface 21u, the first outer peripheral surface 21a, the second outer peripheral surface 21b, and the third outer peripheral surface 21c described above mean the surface of the alumite film 21R. Therefore, the first outer circumferential surface 21a, the second outer circumferential surface 21b, and the third outer circumferential surface 21c are second treated surfaces. Similarly, the peripheral portion 22 has a base 22M and an alumite film 22R formed on the base 22M. That is, the surface 22t, the back surface 22u, the first inner circumferential surface 22a, the second inner circumferential surface 22b, and the third inner circumferential surface 22c described above mean the surface of the alumite film 22R. Therefore, the first inner circumferential surface 22a, the second inner circumferential surface 22b, and the third inner circumferential surface 22c are first treated surfaces. The alumite films 21R and 22R are not formed on the fourth outer peripheral surface 21d of the isolation portion 21 and the fourth outer peripheral surface 22d of the peripheral portion 22.

  As shown in FIG. 4 again, an insulating portion 30 made of resin is provided between the separating portion 21 and the peripheral portion 22. The insulating portion 30 electrically insulates the isolated portion 21 from the peripheral portion 22. Insulating portion 30 is made of, for example, a thermosetting resin having electrical insulation. Insulation portion 30 may be filled, for example, without a gap between isolation portion 21 and peripheral portion 22. Insulating portion 30 may be made of, for example, an epoxy resin. In addition, the material which comprises the insulation part 30 is not restricted to an epoxy resin. The insulating portion 30 may be made of another thermosetting resin.

  The insulating portion 30 surrounds the separating portion 21. In the connection structure 100 provided on the substrate end surface 1c of the substrate 1, the two end surfaces 30c and 30c (fifth side surface portions) of the U-shaped (or C-shaped) insulating portion 30 reach the substrate end surface 1c. There is. In addition, the insulating portion 30 reaches the insulating layer 4 in the thickness direction (see FIG. 2). That is, the insulating portion 30 is in contact with the back surface 4 b of the insulating layer 4 over the entire length.

  More specifically, the insulating portion 30 has a front surface 30t, a back surface 30u, an outer peripheral surface portion 31S, an inner peripheral surface portion 32S, and an end surface 30c. The surface 30 t having a U-shape in plan view is included in the surface 3 a of the base substrate 3 and is in contact with the insulating layer 4. The back surface 30 u having a U-shape in plan view is a surface on the opposite side of the front surface 30 t and is included in the back surface 3 b of the base substrate 3. The outer circumferential surface portion 31S and the inner circumferential surface portion 32S connect the front surface 30t and the back surface 30u.

  The outer peripheral surface portion 31S is joined to the first side surface portion 22S of the peripheral portion 22. Specifically, the outer circumferential surface portion 31S has a first outer circumferential surface 31a, a second outer circumferential surface 31b, and a third outer circumferential surface 31c. The first outer peripheral surface 31a, the second outer peripheral surface 31b, and the third outer peripheral surface 31c face the first side surface 22S of the peripheral portion 22 and are joined to the first side surface 22S. In other words, the first outer peripheral surface 31a, the second outer peripheral surface 31b, and the third outer peripheral surface 31c are joined to the alumite film 22R of the peripheral portion 22 (see FIG. 5). More specifically, the first outer circumferential surface 31 a is joined to the first inner circumferential surface 22 a of the peripheral portion 22. The second outer circumferential surface 31 b is joined to the second inner circumferential surface 22 b of the peripheral portion 22. The third outer peripheral surface 31 c is joined to the third inner peripheral surface 22 c of the peripheral portion 22.

  The inner circumferential surface portion 32S is joined to the second side surface portion 21S of the separating portion 21. Specifically, the inner circumferential surface portion 32S has a first inner circumferential surface 32a, a second inner circumferential surface 32b, and a third inner circumferential surface 32c. The first inner circumferential surface 32a, the second inner circumferential surface 32b, and the third inner circumferential surface 32c face the second side surface 21S of the separating portion 21 and are joined to the second side surface 21S. In other words, the first inner circumferential surface 32a, the second inner circumferential surface 32b, and the third inner circumferential surface 32c are joined to the alumite film 21R of the separating portion 21. More specifically, the first inner circumferential surface 32 a is joined to the first outer circumferential surface 21 a of the separating portion 21. The second inner circumferential surface 32 b is joined to the second outer circumferential surface 21 b of the separating portion 21. The third inner circumferential surface 32 c is joined to the third outer circumferential surface 21 c of the separating portion 21.

  The end face 30 c is not joined to any of the isolation part 21 and the peripheral part 22. The end face 30c is included in the substrate end face 1c.

  Subsequently, a method of manufacturing the connection structure 100 will be described. First, as shown in part (a) of FIG. 6, a U-shaped (or C-shaped) hole 3 </ b> L (sag) is formed in the aluminum plate 3 </ b> A (slit processing). Thereby, the area | region corresponded to the insulation part 30 is formed.

  Next, as shown in part (b) of FIG. 6, the alumite film 3R is formed by subjecting the aluminum plate 3A provided with the holes 3L to an alumite treatment (anodic oxidation treatment). As the alumite treatment, for example, phosphate alumite treatment may be employed. In the alumite treatment of the aluminum plate 3A, the whole of the aluminum plate 3A is immersed in a chemical solution, and a current is applied. According to this operation, the alumite film 3R is formed on the entire surface of the aluminum plate 3A. According to this configuration, the alumite film 3R formed on the front surface, the back surface, and the end surface of the aluminum plate 3A has an effect of enhancing the rigidity of the aluminum plate 3A. The alumite film 3R may not be formed on the front and back surfaces of the aluminum plate 3A. That is, the alumite film 3R may be formed on the second side surface 21S and the first side surface 22S (see FIG. 4).

  Next, as shown in part (c) of FIG. 6, the resin material is embedded in the hole 3L by printing, and the insulating part 30 is formed.

  Next, as shown in part (a) of FIG. 7, the aluminum plate 3A is cut so as to cut both ends of the hole 3L. Thus, a portion corresponding to the end face 30c (substrate end face 1c) is formed. The base substrate 3 is obtained by the above steps.

  Here, the cutting of the base substrate 3 is performed such that the end face 30 c is formed. The isolation portion 21 is connected to the peripheral portion 22 by the insulating portion 30 having three sides. It can be said that this state is a so-called island state. Then, when a load acts on the island portion (isolation portion 21), the load tends to concentrate on the junction interface between the peripheral portion 22 and the insulating portion 30, and the junction interface between the isolation portion 21 and the insulation portion 30. In this state, in the base substrate 3 according to the embodiment, the bonding strength of the insulating portion 30 to the peripheral portion 22 and the bonding strength of the insulating portion 30 to the separating portion 21 are enhanced by the alumite film 3R (see FIG. 5). It is done. More specifically, the alumite film 3R has a porous layer in which a plurality of coated cells having fine pores are arranged. Then, the resin forming the insulating portion 30 is also filled with the fine holes. In the present embodiment, since the alumite treatment using phosphoric acid is performed, the size of the micropores is relatively large, for example, 300 Å or more and 400 Å or less. Then, the bonding area between the insulating portion 30 and the peripheral portion 22 and the separating portion 21 is increased, and the bonding strength is increased by the so-called anchor effect. Therefore, also in the cutting process, the configuration in which the isolation portion 21 is connected to the peripheral portion 22 can be suitably maintained.

  Next, as shown in part (b) of FIG. 7, the insulating layer 4 is formed on the base substrate 3. At this time, the insulating layer 4 is formed to reach the insulating portion 30.

  Subsequently, as shown in part (c) of FIG. 7, a conductive pattern 2 which constitutes a circuit is formed on the insulating layer 4. Furthermore, in the central region surrounded by the insulating portion 30, the through hole 5 penetrating in the thickness direction is formed. Specifically, the through holes 5 are formed so as to penetrate the conductive pattern 2, the insulating layer 4 and the separating portion 21. The terminal 40 is placed on the front surface 2 a of the conductive pattern 2 and screwed into the hole 41 c and the through hole 5 through the bolt 13 with respect to the nut 14 disposed on the back surface 1 b side. It is fixed to

  The order of the above-described steps may be changed appropriately in consideration of manufacturing efficiency and the like.

  The connection structure 100 can be used for any electrical device. For example, as shown in FIG. 8, the connection structure 100 may be applied to an electric compressor 50 in which a large current flows. The electric compressor 50 compresses air and supplies the compressed air to an engine or the like. The electric compressor 50 includes an inverter 54, a motor 52, and a compressor 51 connected to the motor 52 via a rotating shaft 53. The inverter 54 converts direct current power supplied from the power supply 70 into alternating current power, and supplies the alternating current power to the motor 52. The motor 52 is driven by being supplied with AC power from the inverter 54. The compressor 51 attached to the rotating shaft 53 of the motor 52 is rotated by driving the motor 52. The rotation of the compressor 51 compresses the air. Connection structure 100 is provided, for example, in inverter 54. The connection structure 100 may be provided between the power supply 70 and the inverter 54 to electrically connect them (see virtual lines in FIG. 8).

  The electric compressor 50 described above has the substrate 1, and includes the motor 52 whose terminal 40 is electrically connected to the substrate 1 by the connection structure of the terminal 40, and the compressor 51 connected to the motor 52. In this case, the degree of freedom in connection of the terminal 40 can be increased also for the electric compressor 50 where a large current can flow.

  The isolation portion 21 of the substrate 1 is connected to the peripheral portion 22 so as to be electrically insulated. Here, the first outer peripheral surface 21a, the second outer peripheral surface 21b, and the third outer peripheral surface 21c are formed on the second side surface 21S to which the insulating portion 30 is joined. The first outer circumferential surface 21a, the second outer circumferential surface 21b, and the third outer circumferential surface 21c are subjected to an alumite treatment to increase the bonding strength to the insulating portion 30. Further, a first inner circumferential surface 22a, a second inner circumferential surface 22b, and a third inner circumferential surface 22c are formed in the first side surface portion 22S to which the insulating portion 30 is joined. The first inner circumferential surface 22a, the second inner circumferential surface 22b, and the third inner circumferential surface 22c are subjected to an alumite treatment to increase the bonding strength to the insulating portion 30. Then, the insulating portion 30 is firmly joined to the peripheral portion 22 and the separating portion 21. Therefore, it is possible to reliably connect the separating portion 21 to the peripheral portion 22. According to this configuration, the peripheral portion 22 and the joint portion between the isolation portion 21 and the insulating portion 30 can resist the external force acting on the peripheral portion 22 and the isolation portion 21. Therefore, the connected state of the peripheral portion 22 and the isolation portion 21 can be maintained. Thereby, when fixing the terminal 40 with respect to the isolation part 21, it becomes possible to employ | adopt the mechanical structure using a volt | bolt etc. FIG. Therefore, for example, since the restriction associated with the connection structure by soldering is alleviated, the degree of freedom in connection of the terminal 40 to the metal substrate 1 can be enhanced.

  In the above embodiment, the peripheral portion 22 and the isolation portion 21 are formed of aluminum. The first side surface portion 22S and the second side surface portion 21S include alumite films 22R and 21R. The surfaces of the first side surface portion 22S and the second side surface portion 21S are surfaces of the alumite films 22R and 21R. The alumite films 22R and 21R have good bondability to the resin material. Therefore, the bonding strength of the bonding portion between peripheral portion 22 and isolation portion 21 and insulating portion 30 can be reliably increased.

  In the above embodiment, the isolation part 21 has the hole 3 c through which the fastening member 10 for fixing the terminal 40 is inserted. According to this configuration, the terminal 40 can be fixed to the separating portion 21 by using the fastening member 10 of the bolt 13. Therefore, the terminal 40 can be securely fixed to the substrate 1.

  In the above embodiment, the peripheral portion 22 further includes a fourth outer peripheral surface 22 d which is not joined to the insulating portion 30. The isolation portion 21 further has a fourth outer circumferential surface 21 d which is not joined to the insulating portion 30. The insulating portion 30 further includes an end face 30c which is not joined to the peripheral portion 22 and the separating portion 21. The fourth outer peripheral face 22d, the fourth outer peripheral face 21d and the end face 30c are included in the substrate end face 1c. According to this configuration, the isolation portion 21 is disposed at the side portion or the corner portion of the substrate 1. Therefore, the isolation portion 21 surrounded by the peripheral portion 22 and the insulating portion 30 can be easily formed.

  The connection structure of the terminal 40 according to the above embodiment includes the substrate 1, the terminal 40 fixed to the substrate 1, and the fastening member 10 fixing the terminal 40 to the substrate 1. Substrate 1 is formed on plate-like base substrate 3 including peripheral portion 22, isolation portion 21 and insulating portion 30, insulating layer 4 formed on surface 3 a of base substrate 3, and surface 30 t of insulating portion 30. And a conductive pattern 2. The substrate 1 has a through hole 5 which penetrates at least the insulating portion 30 and the separating portion 21 in the thickness direction and is inserted into the hole 41 c of the terminal 40. The fastening member 10 is a shaft 12 inserted through the through hole 5 of the substrate 1 and the hole 41 c of the terminal 40, and a head 11 of a bolt 13 provided at one end of the shaft 12 and pressing the terminal 40 in the thickness direction. And a nut 14 provided at the other end of the shaft portion 12 to press the separating portion 21 in the thickness direction.

  The substrate 1 has a through hole 5 penetrating the insulating layer 4 and the isolation portion 21 in the thickness direction. The shaft 12 of the fastening member 10 is inserted through the through hole 5 and the hole 41 c of the terminal 40. The terminals 40 are fixed to the substrate 1 by the respective ends provided at both ends of the shaft portion 12 being locked to the terminal 40 and the substrate 1 (more specifically, to the separation portion 21). The isolation portion 21 is electrically insulated from the peripheral portion 22 by the insulating portion 30. Therefore, the peripheral portion 22 is electrically insulated from the terminal 40, the fastening member 10 and the separating portion 21, and the peripheral portion 22 is not short-circuited to the terminal 40. According to the structure in which the terminal 40 is fixed to the substrate 1 by using the through hole 5 and the fastening member 10, the restriction associated with the connection structure by soldering, for example, is alleviated. Therefore, the freedom of connection of the terminal 40 to the metal substrate 1 can be enhanced.

  Furthermore, according to the connection structure 100 of the terminal 40, the through hole 5 that penetrates the conductive pattern 2, the insulating layer 4 and the base substrate 3 in the thickness direction is formed in the substrate 1. The shaft 12 of the fastening member 10 is inserted into the through hole 5 and the hole 41 c of the terminal 40. The head 40 and the nut 14 provided at both ends of the shaft portion 12 are locked on the terminal 40 and the base substrate 3 (more specifically, on the separation portion 21), so that the terminal 40 is mounted on the substrate 1 It is fixed. The nut 14 of the fastening member 10 contacts the isolated portion 21 of the base substrate 3, but the isolated portion 21 is insulated with respect to the peripheral portion 22 by the insulating portion 30 which reaches the insulating layer 4. The nut 14 of the fastening member 10 is within the range of the insulating portion 30 and the separating portion 21 and does not contact the peripheral portion 22. Therefore, the peripheral portion 22 is insulated from the terminal 40, the conductive pattern 2, the fastening member 10 and the separating portion 21, and a short circuit between the circuit of the conductive pattern 2 and the peripheral portion 22 of the base substrate 3 does not occur. Thus, since the terminal 40 is connected using the through hole 5 and the fastening member 10 containing the axial part 12, the freedom degree of connection of the terminal 40 with respect to a metal board | substrate is raised.

  For example, since the space of the fastening member 10 only needs to be secured, space saving is realized as compared with the case where the solder portion 210 is provided. In addition, even when a semiconductor element such as a MOSFET is mounted near the conductive member, the situation that the semiconductor element is damaged or destroyed by the heat for soldering is avoided. Further, as in the connection structure 200 shown in FIG. 9, the second connection member 202 which is a terminal of the external circuit is separately fastened by the fastening member 203 to the first connection member 201 soldered in the solder portion 210 It takes time and effort to weld. In the above embodiment, the terminals 40 can be connected with a simple configuration. There is no need to solder the terminals 40, and an excessive amount of heat is not required in the mounting process of the substrate 1, and the thermal stress on other mounted components is reduced. The connection of the terminal 40 such as a bus bar to the substrate 1 is facilitated, and the freedom in shape design of the substrate 1 and the terminal 40 is expanded. Furthermore, the peripheral portion 22 enhances the heat dissipation of the substrate 1. By the peripheral portion 22 being connected to the external cooling means and being cooled, the heat dissipation of the substrate 1 is further enhanced.

  The terminal 40 can be easily fastened and fixed to the substrate 1 by the bolt 13 and the nut 14 of the fastening member 10. The terminal 40 can be directly fastened to the substrate 1 by the bolt 13 and the nut 14.

  Since the insulating portion 30 is provided to reach the substrate end face 1 c of the substrate 1, the insulating portion 30 and the isolation portion 21 surrounded by the insulating portion 30 can be easily formed.

  The rectangular separating portion 21 has a large area as compared with the case where the separating portion 21 is circular. Thus, it is suitable for the bearing surface of the nut 14. Since the insulating portion 30 also has a rectangular shape, the insulating portion 30 can be easily formed. If the nut 14 is rectangular in shape, the standoff 21 conforms to the shape of the nut 14 so that its area can be minimized. As a result, for example, the cooling performance by the peripheral portion 22 can be sufficiently secured.

  When the connection structure 100 is applied to the motor-driven compressor 50, the degree of freedom in connection of the terminal 40 is enhanced even for the motor-driven compressor 50 in which a large current can flow. For example, the terminal 40 can be easily connected to a power substrate (metal substrate) that can be employed for the inverter 54 of the electric compressor 50. The peripheral portion 22 enhances the heat dissipation of the substrate 1. By the peripheral portion 22 being connected to the external cooling means and being cooled, the heat dissipation of the substrate 1 is further enhanced.

  Although the embodiment of the present invention has been described, the present invention is not limited to the above embodiment. For example, the shape of the isolation may be any other shape. The separator may not be provided at the end of the substrate 1.

  The configuration of the fixing member may be changed as appropriate. For example, the shaft portion and the second side surface portion may be integrated, a bolt may be inserted from the back surface 1 b side of the substrate 1, and a nut may be provided on the connection portion 41 side of the terminal 40. A nut pressed against the conductive pattern 2 and a nut pressed against the base substrate 3 may be screwed into the stud bolt. Other than the fastening member may be adopted. For example, a rivet structure or a socket structure may be employed. A caulking structure may be employed.

  The connection structure 100 may be applied to a noncontact power feeding system or the like.

  The alumite film 21R of the separation portion 21 may be formed on at least the first outer peripheral surface 21a, the second outer peripheral surface 21b, and the third outer peripheral surface 21c. That is, the alumite film 21R may not be formed on the front surface 21t and the back surface 21u of the isolation portion 21.

  Similarly, the alumite film 22R of the peripheral portion 22 may be formed on at least the first inner peripheral surface 22a, the second inner peripheral surface 22b, and the third inner peripheral surface 22c. That is, the alumite film 22R may not be formed on the surface 22t and the back surface 22u of the peripheral portion 22.

  Moreover, in the said embodiment, the alumite process was illustrated as a process which raises joint strength with an insulation part. The process of increasing the bonding strength is a process of increasing the contact area with the resin material forming the insulating portion 30. Therefore, the treatment for increasing the bonding strength includes surface treatment and modification treatment capable of increasing the contact area. For example, when the base substrate 3 is aluminum, it is an alumite treatment. Further, as described later, when the base substrate 3 is copper, blackening processing is performed. That is, the process of increasing the bonding strength with the insulating portion may include a process of increasing the contact area depending on the metal material constituting the base substrate 3.

  Further, in the above embodiment, the base substrate 3 is formed of aluminum. However, the metal material forming the base substrate is not limited to aluminum. For example, copper may be used as the metal material. Then, as a process of enhancing the bonding strength with the insulating portion, a process of roughening the surface of the copper substrate can be employed. That is, the process of increasing the bonding strength is a process of increasing the contact area with the resin material constituting the insulating portion 30. In the case of a copper substrate, examples of the surface roughening treatment include blackening treatment (blackening treatment).

1 board (circuit board)
1a front surface 1b back surface 1c substrate end surface 2 conductive pattern (conductive pattern portion)
2a front surface 2b back surface 2c hole 3 base substrate (base plate portion)
3a front surface 3b back surface 3c hole 3A aluminum plate 3L hole 3R alumite film 4 insulating layer (insulating layer)
4a front surface 4b back surface 4c hole 5 through hole 10 fastening member (fixing member)
11 head 12 shaft portion 13 bolt 14 nut 21 isolated portion (second substrate portion)
21a first outer peripheral surface 21b second outer peripheral surface 21c third outer peripheral surface 21d fourth outer peripheral surface 21t front surface 21u back surface 21S second side surface portion 21T fourth side surface portion 21R alumite film 21M base 22 peripheral portion (first substrate portion)
22a first inner circumferential surface 22b second inner circumferential surface 22c third inner circumferential surface 22d fourth outer circumferential surface 22t front surface 22u back surface 22S first side surface portion 22T third side surface portion 22R alumite film 22M base 30 insulating portion 30c end surface (fifth surface Side part)
30t front surface 30u back surface 31S outer peripheral surface 31a first outer peripheral surface 31b second outer peripheral surface 31c third outer peripheral surface 32S inner peripheral surface 32a first inner peripheral surface 32b second inner peripheral surface 32c third inner peripheral surface 40 terminal 41 connecting portion 41c Hole portion 42 Lead portion 50 Electric compressor 51 Compressor 52 Motor 53 Rotation shaft 54 Inverter 70 Power source 100 Connection structure 200 Connection structure 201 First connection member 202 Second connection member 203 Fastening member 210 Solder portion S Notched portion

Claims (7)

A first substrate portion which is a metal plate having a first side surface portion and on which an electric circuit is formed;
A metal plate having a second side surface portion, and a second substrate portion to which a conductive member connected to the electric circuit is fixed;
A resin which is interposed between the first side surface portion and the second side surface portion, couples the second substrate portion to the one substrate portion and electrically insulates the second substrate portion from the first substrate portion. , With insulation made of
The first side surface portion includes a first treated surface joined to the insulating portion and subjected to a treatment for enhancing the bonding strength with the insulating portion,
The circuit board, wherein the second side surface portion is joined to the insulating portion, and includes a second treated surface treated to increase the joint strength with the insulating portion.   The circuit board according to claim 1, wherein the first processing surface and the second processing surface are surfaces on which surface treatment or modification treatment has been performed to increase bonding strength with the insulating portion. The first substrate portion and the second substrate portion are formed of aluminum,
The first side portion and the second side portion include an alumite film,
The circuit board according to claim 1, wherein the first treated surface and the second treated surface are surfaces of the alumite film.   The circuit board according to any one of claims 1 to 3, wherein the second substrate portion has a through hole through which a fixing member for fixing the conductive member is inserted. The first substrate portion further includes a third side surface portion not bonded to the insulating portion,
The second substrate portion further includes a fourth side surface portion not bonded to the insulating portion,
The insulating portion further includes a fifth side surface portion not joined to the first substrate portion and the second substrate portion,
The circuit board according to any one of claims 1 to 4, wherein the third side surface portion, the fourth side surface portion, and the fifth side surface portion are included in a substrate end surface. The circuit board according to any one of claims 1 to 5, and
A conductive member fixed to the circuit board;
And a fixing member for fixing the conductive member to the circuit board,
The circuit board is
A plate-shaped base plate portion including the first substrate portion, the second substrate portion, and the insulating portion;
An insulating layer portion formed on the surface of the base plate portion;
And a conductive pattern portion formed on the surface of the insulating portion,
The circuit board has a through hole which penetrates the conductive pattern portion, the insulating portion and the second substrate portion in the thickness direction and is inserted into a hole of the conductive member.
The fixing member is
A shaft portion inserted through the through hole of the circuit board and the hole of the conductive member;
A first end provided at one end of the shaft to press the conductive member in the thickness direction;
And a second end provided at the other end of the shaft portion and pressing the second substrate portion in the thickness direction. A motor comprising the circuit board, wherein the conductive member is electrically connected to the circuit board by the connection structure of the conductive member according to claim 6;
And a compressor coupled to the motor.

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