JP6928092B2 - Manufacturing method of electric circuit device, power conversion device and circuit body housing case - Google Patents

Description

The present invention relates to a method for manufacturing an electric circuit device, a power conversion device, and a circuit body accommodating case.

A power semiconductor module applied to a vehicle such as an automobile has a power conversion circuit that converts DC power into AC power or AC power into DC power. The power conversion circuit includes a power semiconductor element that generates a large amount of heat. Therefore, the case of the power semiconductor module is usually formed of a metal having fins for heat dissipation. Then, the case in which the circuit body is housed is housed in the flow path forming body having the refrigerant flow path.

The power semiconductor module and the flow path forming body accommodate a sealing member in a recess formed in the case of the power semiconductor module, and the sealing member is a seal formed in an opening for inserting the power semiconductor module in the flow path forming body. Press-fit into the part and seal to the outside. The power semiconductor module has a flange having an annular O-ring groove formed on the outer periphery thereof, and a seal member housed in the O-ring groove is pressed against an inner wall surface formed in the flow path forming body to form a watertight structure ( For example, see Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-61454

Patent Document 1 does not describe watertightness, but if the inner surface of the O-ring groove is rough, the watertightness is not sufficient, and if the inner surface of the O-ring groove is processed to reduce the surface roughness, productivity is achieved. Decreases.

According to the first aspect of the present invention, the electric circuit device includes a circuit body constituting an electric circuit, a circuit body accommodating portion formed by casting and accommodating the circuit body, and a recess in which a sealing material is accommodated. , and a said combined portion formed corresponding to the facing portion of the upper and lower molds used in casting, one or, and a case in which the recess is formed across the mating portion, the recess The bottom surface and the pair of side surfaces of the recess have a work area and a non-work area, respectively, and the bottom surface and the pair of side surfaces in the work area have a bottom surface and a pair of side surfaces. In each case, the surfaces of the mating portion and the peripheral edge of the mating portion are removed, and each of the pair of side surfaces in the non-processed region has a pair of inclined surfaces formed with the processed region interposed therebetween. Each of the inclined surfaces of the above is inclined in opposite directions from each end toward the work area so that the side surface of the work area becomes the top surface.
According to the second aspect of the present invention, the power conversion device has the electric circuit device of the first aspect and the case accommodating portion for accommodating the case of the electric circuit device, and faces the recess of the case. A flow path forming body having a sealing portion and a sealing member housed in the recess of the case and watertightly closing the sealing portion and the case of the flow path forming body with respect to the outside are provided.
According to a third aspect of the present invention, a manufacturing method of the circuit accommodating case are that the circuit accommodating part circuit constituting the electrical circuit is accommodated, the case having a recess, formed by casting, After forming the case, the formation of the case includes removing the surface of a part of the concave portion of the case, and the formation of the case includes a mating portion corresponding to the facing portion of the upper and lower molds used in the casting. Forming and the recess crossing the mating portion and having a bottom surface and a pair of side surfaces, the pair of side surfaces are respectively on both sides of the mating portion and the mating portion with the mating portion interposed therebetween. It has a pair of side portions provided, and each of the pair of side portions forms the recess so as to have an inclined surface inclined in a direction with the mating portion as an apex. Including, removing the surface of a part of the recess of the case includes removing the surface of the mating portion and the peripheral edge of the mating portion, respectively, of the bottom surface and the pair of side surfaces of the recess.

According to the present invention, it is possible to improve productivity and watertightness.

It is an external perspective view of the 1st Embodiment which shows the electric circuit apparatus of this invention as an example of a power semiconductor module. It is an exploded perspective view of the power semiconductor module illustrated in FIG. It is an exploded perspective view of the circuit body illustrated in FIG. It is a circuit diagram which shows an example of the circuit of the circuit body illustrated in FIG. FIG. 5 is an external view of the frame body of the case shown in FIG. 2, showing the structure immediately after casting. FIG. 6 is an enlarged view of the region VI of FIG. 5 as viewed from the X direction. 7 (a) shows the processed structure of the frame shown in FIG. 5, and FIG. 7 (b) is an enlarged view of the region VIIb of FIG. 7 (a). 8 (a) is an enlarged view of FIG. 7 (b) viewed from the X direction, and FIG. 8 (b) is a plan view of FIG. 7 (b) viewed from above. 9 is a schematic view for explaining a method of cutting the inner surface of the concave portion of the flange, and FIG. 9A is a side view of the region IX shown in FIG. 5 as viewed from the y direction, and FIG. 9A is a side view. (B) is a plan view of FIG. 9 (a) as viewed from above. FIG. 10 is a plan view of the vicinity of the bottom surface to be machined 111a formed in the recess, and is the same as FIG. 8 (b). FIG. 11 is an exploded perspective view of the case shown in FIG. 2 before joining. FIG. 12 is a perspective view for explaining a method of manufacturing the case. FIG. 13 is a cross-sectional view showing an example of the power conversion device of the present invention. FIG. 14 shows a second embodiment of the power semiconductor module of the present invention, and FIG. 14 (a) is a view corresponding to FIG. 7 (b) showing the vicinity of the workpiece surface of the concave portion of the flange. 14 (b) is a plan view of FIG. 14 (a) viewed from above, and is a view corresponding to FIG. 8 (b).

− First Embodiment −
The first embodiment of the present invention will be described with reference to FIGS. 1 to 11.
FIG. 1 is an external perspective view of the first embodiment showing the electric circuit device of the present invention by taking a power semiconductor module as an example, and FIG. 2 is an exploded perspective view of the power semiconductor module shown in FIG. ..
The power semiconductor module 1 includes a circuit body 100 and a case 101. The case 101 has a circuit body accommodating portion for accommodating the circuit body 100. The case 101 has a structure in which the base portions 105 and 106 (see FIG. 11 for 106) having a plurality of fins 105A and 106A (see FIG. 11) formed on one surface thereof are joined to the frame body 102 by friction stir welding. In FIGS. 1 and 2, the joint portion 107 between the frame body 102 and the base portion 105 is shown by a dotted line. In the case 101, a flange 120 having an opening 156 is integrally formed with the frame body 102.

The circuit body 100 is housed in the circuit body accommodating portion of the case 101 through the opening 156 of the case 101. The circuit body 100 has a structure in which power semiconductor elements 328, 330 (see FIG. 3) and the like are covered with conductor plates 318, 319 and the like and sealed by a sealing body 302 (see FIG. 2). The circuit body 100 includes an upper arm control terminal 327U, a lower arm control terminal 327L, and a main terminal 100C. Referring to FIG. 2, the circuit body 100 is housed in the circuit body accommodating portion of the case 101 with the insulating members 104 arranged on the front and back surfaces. The upper arm control terminal, the lower arm control terminal 327L, and the main terminal 100C of the circuit body 100 are led out from the opening 156 of the case 101 to the outside. In this state, the sealing resin 303 (see FIG. 1) is filled between the circuit body 100 and the circuit body accommodating portion of the case 101.

The flange 120 of the case 101 is formed with a recess 110 along the outer peripheral side surface. The recess 110 is formed as an annular groove provided on the entire outer peripheral surface of the flange 120. An annular sealing material 103 is housed in the recess 110 formed in the flange 120. The sealing material 103 is compressed between the inner surface of the recess 110 of the flange 120 and the inner wall surface 421 (see FIG. 13) of the flow path forming body 400 (see FIG. 13) to form a watertight structure. The details will be described later.

FIG. 3 is an exploded perspective view of the circuit body shown in FIG. 2, and FIG. 4 is a circuit diagram showing an example of the circuit of the circuit body shown in FIG.
An example of the structure and circuit of the circuit body 100 will be described with reference to FIGS. 3 and 4.
The circuit body 100 has one or a plurality of power semiconductor elements 328 and 330 constituting the upper arm and the lower arm, respectively, and a number of diodes 356 and 366 corresponding to the power semiconductor elements 328 and 330. The upper arm control terminal 327U is formed of a conductive material and is electrically connected to the control electrode of the power semiconductor element 328. The lower arm control terminal 327L is formed of a conductive material and is electrically connected to the control electrode of the power semiconductor element 330. The AC conductor plate 318 connects the emitter electrode of the power semiconductor element 328 and the anode electrode of the diode 356. The N conductor plate 319 connects the emitter electrode of the power semiconductor element 330 and the anode electrode of the diode 366. The upper arm conductor plate 315 connects the collector electrode of the power semiconductor element 328 and the cathode electrode of the diode 356. The lower arm conductor plate 320 connects the collector electrode of the power semiconductor element 330 and the cathode electrode of the diode 366.

The N conductor plate 319 has an N conductor plate connecting portion 319A extending to the main terminal 100C side. The upper arm conductor plate 315 and the lower arm conductor plate 320 each have a DC positive electrode terminal 315D and an AC terminal 320D extending to the main terminal 100C side.
The main terminal 100C includes a DC positive electrode terminal 315D, a DC negative electrode terminal 319D, and an AC terminal 320D. The DC negative electrode terminal 319D is connected to the N conductor plate connecting portion 319A.
The DC positive electrode terminal 315D and the DC negative electrode terminal 319D are each connected to a battery (not shown). Further, the AC terminal 320D is connected to other electronic components such as a capacitor constituting an inverter (not shown) circuit.

The power semiconductor element 328 and the diode 356 are arranged so as to be sandwiched between the AC conductor plate 318 and the upper arm conductor plate 315, and both sides thereof are soldered to the AC conductor plate 318 and the upper arm conductor plate 315, respectively. The power semiconductor element 330 and the diode 366 are arranged so as to be sandwiched between the N conductor plate 319 and the lower arm conductor plate 320, and both sides thereof are soldered to the N conductor plate 319 and the lower arm conductor plate 320, respectively.
The AC conductor plate 318 and the lower arm conductor plate 320 are electrically connected by an intermediate connecting portion 329 (see FIG. 4). Although not shown, the intermediate connecting portion 329 is integrally formed with the AC conductor plate 318 or the lower arm conductor plate 320.

The entire circuit body 100 is sealed and integrated by a sealing body 302 (see FIG. 2). That is, the periphery of the AC conductor plate 318, the upper arm conductor plate 315, the N conductor plate 319, and the lower arm conductor plate 320 is sealed by the sealing body 302. A sealant 302 is also filled between the AC conductor plate 318 and the upper arm conductor plate 315, and between the N conductor plate 319 and the lower arm conductor plate 320, and the power semiconductor elements 328 and 330 and the diodes 356 and 366 are filled. The periphery is covered with a sealing body 302. The sealing body 302 is formed flush with the outer surfaces of the AC conductor plate 318 and the N conductor plate 319 on one surface side. That is, as shown in FIG. 2, the outer surfaces of the AC conductor plate 318 and the N conductor plate 319 are exposed from the sealing body 302. Further, the sealing body 302 is formed flush with the outer surfaces of the upper arm conductor plate 315 and the lower arm conductor plate 320 on the other surface side. That is, the outer surfaces of the upper arm conductor plate 315 and the lower arm conductor plate 320 are exposed from the sealing body 302. Further, as shown in FIG. 2, the upper / lower arm control terminals 327U and 327L and the main terminal 100C are exposed from the sealing body 302 except for a part on the root side.

FIG. 5 is an external view of the frame body of the case shown in FIG. 2, showing the structure immediately after casting.
The frame body 102 constituting the case 101 is formed by die-casting aluminum. The frame body 102 has a frame portion 151 having a rectangular opening 152 and a flange 120. At the peripheral edge of the opening 152 of the frame portion 151, a step portion 153 to which the base portions 105 and 106 (see FIG. 11) are fixed is formed. The pair of left and right side portions 155 of the frame portion 151 are provided with recesses 154 into which the holding jig 221 (see FIG. 12) is inserted. Two pairs of recesses 154 are provided at each of the side portions 155 so as to be separated in the vertical direction. That is, the recesses 154 are provided on the front surface side and the back surface side at two locations in the vertical direction. The recess 154 has an L-shape and is opened on the front surface side or the rear surface side and the side portion 155 side of the frame portion 151.

FIG. 6 is an enlarged view of the region VI of FIG. 5 as viewed from the X direction.
As shown in FIGS. 5 and 6, the flange 120 is provided with an annular recess 110 provided on the entire circumference of the outer peripheral surface. The recess 110 has a pair of semicircular curved portions 110a and a pair of linear lateral portions 110b connecting the curved portions 110a. The recess 110 has a bottom surface 111, and a lower side surface 121 and an upper side surface 122 that rise on both sides of the bottom surface 111. The frame body 102 is formed by casting aluminum die casting or the like. Therefore, as shown in FIG. 6, a mating portion 141 is formed at substantially the center of the frame body 102 in the thickness direction (y direction) corresponding to the facing portions of the upper and lower molds. In the present embodiment, the recess 110 is exemplified as a structure formed orthogonal to the mating portion 141. Since the recess 110 is formed in an annular shape and crosses the facing portions of the upper and lower molds, a mating portion 141 is formed on the bottom surface 111, the lower side surface 121, and the upper side surface 122 of the recess 110 in this portion.

That is, as shown in FIG. 6, the frame body 102 has a structure in which the two divided portions 131 and 132 are integrated with the mating portion 141 as a boundary.
Therefore, the lower side surface 121 of the recess 110 has a lower inclined surface 121a formed in one of the divided portions 131 and a lower inclined surface 121b formed in the other divided portion 132. Further, the upper side surface 122 of the recess 110 has an upper inclined surface 122a formed in one of the divided portions 131 and an upper inclined surface 122b formed in the other divided portion 132.
The lower side surface 121 and the upper side surface 122 of the recess 110 require a draft when they are taken out from the mold.
The lower inclined surface 121a and the lower inclined surface 121b are inclined surfaces that are inclined in the direction in which the mating portion 141 is the apex. Similarly, the upper inclined surface 122a and the upper inclined surface 122b are inclined surfaces that are inclined in the direction in which the mating portion 141 is the apex.

The mating portion 141 has steps and burrs due to misalignment of the upper and lower molds. The steps and burrs form a gap with the sealing material 103 and reduce the watertightness. Further, steps and burrs damage the sealing material 103. Therefore, it is necessary to remove steps and burrs by cutting or the like. However, if the entire area of the inner surface of the recess 110 is machined, the productivity is reduced.

7 (a) shows the processed structure of the frame shown in FIG. 5, FIG. 7 (b) is an enlarged view of the region VIIb of FIG. 7 (a), and FIG. 8 (a) is. 7 (b) is an enlarged view of FIG. 7 (b) viewed from the X direction, and FIG. 8 (b) is a plan view of FIG. 7 (b) viewed from above. However, in FIG. 8B, the portion of the flange 120 above the recess 110 is removed and shown.
In the frame body 102 illustrated in FIG. 7 (a), In its contact on both sides of the flat outer surface and a surface of the stepped portion 153 of the frame portion 151 surface during the casting is removed by cutting. Further, the surfaces around the mating portion 141 on the bottom surface 111, the lower side surface 121, and the upper side surface 122 of the recess 110 of the flange 120 are removed by cutting.
As shown in FIG. 8B, the bottom surface to be machined 111a on the bottom surface 111 of the recess 110 is a flat surface parallel to the surface in contact with the curved surface in the mating portion 141 of the curved portion 110a. The bottom surface to be machined 111a is formed in a narrow region centered on the mating portion 141 of the curved portion 110a. That is, the bottom surface to be processed 111a is formed only in a part of the central portion of the curved portion 110a. In FIG. 8B, the bottom surface to be machined 111a is shown by a thick line for easy understanding.

As shown in FIG. 8A, the lower side surface processed surface 121c of the lower side surface 121 of the recess 110 and the upper side surface processed surface 122c of the upper side surface 122 are flat surfaces parallel to each other. The lengths of the lower side surface to be machined 121c and the upper side surface to be machined 122c in the thickness direction (y direction) of the case 101 shown in FIGS. 8A and 8B are the bottom surface to be machined 111a, respectively. It is formed to be almost the same length.

The lower inclined surface 121a is inclined at an angle of inclination angle θ1 with respect to the lower side surface processed surface 121c, and the lower inclined surface 121b is inclined at an angle of an inclination angle θ2 with respect to the lower side surface processed surface 121c. The inclination angle θ1 and the inclination angle θ2 are angles in opposite directions with respect to the lower side surface to be processed surface 121c, but the absolute values may be the same or different. That is, the lower inclined surface 121a and the lower inclined surface 121b are inclined in opposite directions from each end of the flange 120, that is, the case 101 in the thickness direction so that the lower side surface to be processed 121c is the top surface. doing.
The structure on the upper side surface 122 side is also the same as that of the lower side surface, and the upper inclined surface 122a and the upper inclined surface 122b are respectively inclined at a predetermined inclination angle with respect to the upper side surface processed surface 122c. The absolute values of the inclination angles of the upper inclined surface 122a and the upper inclined surface 122b with respect to the upper side surface to be processed 122c may be the same or different. That is, the upper inclined surface 122a and the upper inclined surface 122b are inclined in opposite directions from each end of the flange 120, that is, the case 101 in the thickness direction so that the upper side surface to be processed 122c is the top surface. doing.
The absolute values of the inclination angles of the upper inclined surface 122a and the upper inclined surface 122b with respect to the upper side surface to be processed 122c and the absolute values of the inclination angles of the lower inclined surface 121a and the lower inclined surface 121b with respect to the lower side surface to be processed 121c are the same. May be good.

9 is a schematic view for explaining a method of cutting the inner surface of the concave portion of the flange, and FIG. 9A is a side view of the region IX shown in FIG. 5 as viewed from the y direction, and FIG. 9A is a side view. (B) is a plan view of FIG. 9 (a) as viewed from above.
In order to efficiently cut the inner surface of the recess 110 of the flange 120, a cutting tool 201 having a rotary cutting portion having an axis (z axis) parallel to the bottom surface 111 of the recess 110 as an axis is used. The thickness (length in the z direction) of the cutting tool 201 is the same as the length between the lower side surface to be machined 121c and the upper side surface to be machined 122c. First, as shown in FIG. 9B, the height position of the cutting tool 201 is adjusted to the height position of the recess 110 at a position deviated from the curved portion 110a of the recess 110 in the y direction. That is, the height position is adjusted so that the upper surface 201a of the cutting tool 201 becomes the position of the upper side surface to be machined 122c after cutting and the lower surface 202b becomes the position of the lower machined surface 121c. Further, the tip side portion of the outer peripheral cutting surface of the cutting tool 201 in the x direction is located at the position of the bottom surface to be machined 111a (indicated by the alternate long and short dash line in FIG. 9B) after cutting. Adjust the position of. Then, the cutting tool 201 moves in the y direction while rotating. As the cutting tool 201 moves in the y direction, the lower inclined surfaces 121a and 121b and the upper inclined surfaces 122a and 122b are cut to form the upper side surface to be machined 122c and the lower machined surface 121c. At the same time, the bottom surface to be machined 111a is formed.

It is preferable that the lower inclined surfaces 121a and 121b and the upper inclined surfaces 122a and 122b formed in the recess 110 have a small inclination angle. However, if this inclination angle is too small, the cutting tool 201 is slightly displaced in the height direction (z direction), and the cutting tool 201 is formed on the mating portion 141 between the lower inclined surfaces 121a and 121b and between the upper inclined surfaces 122a and 122b. The formed steps and burrs cannot be removed. On the contrary, when the inclination angles of the lower inclined surfaces 121a and 121b and the upper inclined surfaces 122a and 122b formed in the recess 110 become too large, as shown in FIG. 9B, the region cut by the cutting tool 201 and the non-cutting area are not cut. A step 181 is formed between the region and the region. The step 181 damages the sealing material 103. Therefore, the inclination angles of the lower inclined surfaces 121a and 121b and the upper inclined surfaces 122a and 122b need to be kept within an appropriate range. Regarding the power semiconductor module 1 of the present embodiment, the inclination angles of the lower inclined surfaces 121a and 121b with respect to the lower side surface processed surface 121c and the upper inclined surfaces 122a and 122b with respect to the upper side surface processed surface 122c are preferably about 1 to 2 degrees. .. However, this inclination angle is appropriately adjusted to an optimum value depending on the usage environment of the device, the material of the sealing material 103, and the like.

FIG. 10 is a plan view of the vicinity of the bottom surface to be machined 111a formed in the recess, and is the same as FIG. 8 (b). However, in FIG. 10, the upper flange 120 is removed and shown.
Since the bottom surface to be machined 111a formed on the curved portion 110a of the recess 110 is formed by linearly cutting the peripheral surface of the curved portion 110a, the boundary between the bottom surface to be machined 111a and the non-processed portion of the bottom surface 111. A bent portion 161 is formed in the portion. If the bending angle of the bent portion 161 is too large, the sealing material 103 is damaged. The bending angle α between the tangent line 162 of the bent surface and the bottom surface processed surface 111a in the bent portion 161 becomes smaller as the bottom surface processed surface 111a becomes closer to the tip end side of the curved portion 110a. Therefore, it is preferable that the bottom surface to be machined 111a is not cut from the tip of the curved portion 110a to a position too deep. In the power semiconductor module 1 of the present embodiment, the bending angle α between the tangent line 162 of the bending surface and the bottom surface to be machined 111a in the bending portion 161 is preferably about 0 to 20 degrees, more preferably about 0 to 16 degrees. That is, it is preferable that the temperature is larger than 0 degrees and is as close to 0 degrees as possible.

FIG. 11 is an exploded perspective view of the case shown in FIG. 2 before joining, and FIG. 12 is a perspective view for explaining a method of manufacturing the case.
As shown in FIG. 11, the case 101 has a frame body 102 and a base portion 105 formed with a plurality of fins 105A and 106A (see FIG. 13 for 106A) joined to both the front and back surfaces of the frame body 102. It is equipped with 106. The fins 105A and 106A are integrally formed with the base portions 105 and 106, respectively, and are made of a material having high thermal conductivity such as pure aluminum.
The frame body 102 has a frame portion 151 having an opening 152 in the center, and a step portion 153 is formed on the peripheral edge of the opening 152 on each of the front and back surfaces of the frame portion 151. The frame body 102 including the frame portion 151 is a material having a higher Young's modulus than the base portions 105 and 106. For example, it is formed by ADC12 or the like. The ADC 12 has good workability during cutting. As described above, the flat outer surfaces on both the front and back sides of the frame portion 151 and the surface of the step portion 153 are removed by cutting. Then, the base portion 105 having the fins 105A and the base portion 106 having the fins 106A each close the opening 152 of the frame portion 151 and are joined to the peripheral edge portion of the opening 152 of the frame portion 151.
Hereinafter, a method of joining the frame portion 151, the frame portion 151, and the base portions 105 and 106 will be described.

The frame body 102 shown in FIG. 11 is the one shown in FIG. 7 in which the flat outer surfaces on both the front and back sides of the frame portion 151 and the surface of the step portion 153 are cut to remove the surface at the time of casting. A base portion 105 having fins 105A is fitted into a step portion 153 on the peripheral edge of an opening 152 on the front surface side of the frame portion 151. Then, as shown in FIG. 12, the side of the frame 102 opposite to the base portion 105 is received and placed on the jig 222. The receiving jig 222 is formed with an opening 222a in which the flange 120 of the frame body 102 can be inserted in the central portion. Further, the receiving jig 222 is provided with a recess (not shown) that holds a pair of side portions 155 of the frame portion 151 and accommodates the fins 105A and 106A in this state. Therefore, the pair of side portions 155 of the frame body 102 can be reliably held by the jig 222.

After the frame body 102 is stably fixed to the receiving jig 222 in this way, one end of the pressing jig 221 is inserted into the recesses 154 formed in each side portion 155, and the frame body 102 is inserted by the pressing jig 221. It is pressed against the receiving jig 222. As shown in FIG. 12, since a plurality of recesses 154 are formed in each frame portion 151 of the frame body 102, the frame body 102 is received by these pressing jigs 221 and pressed against the jig 222. , The frame body 102 is fixed to the receiving jig 222 in a stable state.

In this state, as shown in FIG. 12, the joining tool 220 is moved along the boundary between the peripheral edge portion of the base portion 105 and the step portion 153 of the frame body 102, and the frame is formed by, for example, friction stir welding or the like. The body 102 and the base portion 105 are joined at the joint portion 107.
After that, the frame body 102 to which the base portion 105 is joined is turned upside down, and the frame body 102 and the base portion 106 having the fins 106A are joined by the same method.

In this way, the case 101 shown in FIG. 2 is formed.
It should be noted that either of the cutting of the concave portion 110 of the flange 120 of the frame body 102 and the cutting of the flat outer surface on both the front and back sides of the frame portion 151 of the frame portion 151 and the surface of the step portion 153 is performed first. good.

FIG. 13 is a cross-sectional view showing an example of the power conversion device of the present invention.
The power conversion device 500 includes a power semiconductor module 1 and a flow path forming body 400.
Inside the flow path forming body 400, a flow path 420 through which the refrigerant flows is formed. The flow path forming body 400 has an insertion port 410 that is open to the outside on the side opposite to the bottom. A sealing material 103 is mounted in the recess 110 formed in the flange 120 of the case 101 of the power semiconductor module 1. The sealing material 103 seals the insertion port 410 and seals the flow path 420. The power semiconductor module 1 is inserted from the lower end side of the case 101, that is, the opposite sides of the upper / lower arm control terminals 327U, 327L and the main terminal 100C of the circuit body 100 into the insertion port 410 of the flow path forming body 400. It is pushed into the flow path 420.

The outer peripheral side of the sealing material 103 protruding from the recess 110 formed in the flange 120 abuts on the inner wall surface 421 of the flow path 420 at the insertion port 410 of the flow path forming body 400. In this state, when the power semiconductor module 1 is pushed into the bottom surface side of the flow path 420 of the flow path forming body 400, the sealing material 103 is placed between the recess 110 of the case 101 and the inner wall surface 421 of the flow path forming body 400. It is compressed. As a result, the power semiconductor module 1 and the flow path forming body 400 are watertightly fixed by the sealing material 103.

According to the first embodiment, the following effects are obtained.
(1) The power semiconductor module (electrolytic circuit device) 1 has a recess 110 in which a sealing material 103 is housed, and a plurality of divided portions 131 and 132 are integrated by a mating portion 141, and the recess 110 is a mating portion. It includes a case 101 formed across 141. The recess 110 has a bottom surface 111 and a pair of side surfaces 121 and 122. The bottom surface 111 of the recess 110 and the pair of side surfaces 121 and 122 have surfaces to be processed (areas to be processed) 111a, 121c and 122c and non-processed areas, respectively. The bottom surface 111 and the pair of side surfaces 121 and 122 on the surfaces 111a, 121c and 122c to be machined have their surfaces removed from the mating portion 141 and the peripheral surface of the mating portion 141, respectively. It has a pair of inclined surfaces 121a, 121b or 122a, 122b formed with the side surface processed surfaces 121c, 122c interposed therebetween, and each of the pair of inclined surfaces 121a, 121b or 122a, 122b has a side surface processed surface 121c, They are inclined in opposite directions from each end toward the side surface to be processed 121c and 122c so that 122c is the top surface.

That is, in the recess 110 of the case 101, the mating portion 141 and the peripheral portion thereof are the surfaces to be processed 111a, 121c, 122c, and the other portions are non-processed regions in the state obtained by casting. Therefore, it is possible to shorten the working time required for processing and improve the productivity, and to improve the watertightness of the sealing material 103 housed in the recess 110 at the same time.
When the surface of the cast product is machined, the possibility that the inner cavity is exposed on the surface of the recess 110 increases. When the nest is exposed on the surface of the recess 110, a gap is formed between the sealing material 103 and the inner surface of the recess 110, and the watertightness cannot be maintained. According to the present embodiment, since the region to be machined in the recess 110 of the case 101 is reduced, it is possible to suppress a potential defect that the internal nest is exposed. In particular, as in the present embodiment, this effect is large in a structure in which the area of the non-processed region is larger than the area of the processed surfaces 111a, 121c, 122c of the mating portion 141 and the peripheral portion thereof of the recess 110.

(2) The recess 110 has a pair of curved portions 110a and a pair of side portions 110b connecting the pair of curved portions 110a, and the surface to be machined (processed region) 111a is within the region of the curved portion 110a. It is provided in. In this structure, it is only necessary to process a part of the curved portion 110a, which is complicated to process, so that the work efficiency can be improved.

(3) The bottom surface 111 of the curved portion 110a on the processed surface (processed region) 111a, 121c, 122c is a flat surface from which the surfaces of the mating portion 141 and the peripheral edge of the mating portion 141 have been removed. In this structure, the surface to be machined (region to be machined) 111a can be formed only by flattening the bottom surface 111 of the curved portion 110a. Therefore, the work efficiency of the work surface 111a can be improved as compared with the structure in which the work is performed along the curved surface.

(4) The case 101 includes base portions 105 and 106 having fins 105A and 106A and a frame portion 151 for holding the base portions 105 and 106, and the frame portion 151 has a Young's modulus higher than that of the base portions 105 and 106. Has. Therefore, the case 101 can suppress and hold the deformation of the base portions 105 and 106 even when an external force is applied to the frame portion 151.

-Second embodiment-
FIG. 14 shows a second embodiment of the power semiconductor module of the present invention, and FIG. 14 (a) is a view corresponding to FIG. 7 (b) showing the vicinity of the workpiece surface of the concave portion of the flange. 14 (b) is a plan view of FIG. 14 (a) viewed from above, and is a view corresponding to FIG. 8 (b).
In the first embodiment, the structure is illustrated as a structure in which a flat bottom surface to be processed 111a is formed on the bottom surface 111 of the recess 110 of the frame body 102. In the second embodiment shown in FIG. 14, the bottom surface 111 of the recess 110 has a structure in which a bottom surface to be machined 111b curved along the curved surface of the bottom surface 111 is formed. That is, the bottom surface 111 around the mating portion 141 in the curved portion 110a of the recess 110 is cut into a curved shape to form the bottom surface to be machined 111b. The bottom surface to be processed 111b is formed in the central portion of the curved portion 110a as in the first embodiment.

The lower side surface to be processed 121c and the upper side surface to be processed 122c (not shown in FIG. 14) are flat surfaces parallel to each other as in the first embodiment, and are formed in the thickness direction (y direction). It is formed to have substantially the same length as the bottom surface to be machined 111b. In FIG. 14B, the bottom surface to be machined 111b is shown by a thick line for easy understanding. The formation of the bottom surface processed surface 111b, the lower side surface processed surface 121c, and the upper side surface processed surface 122c is the same as in the first embodiment. However, in the second embodiment, since the bottom surface to be machined 111b has a curved shape, the cutting tool 201 does not move linearly in the y direction, but the recess 110 is centered on the mating portion 141. The curvature is moved so as to draw a circle or an ellipse so that the curvature is slightly larger than the curvature of the curvature 110a.

Other configurations in the second embodiment are similar to those in the first embodiment.
Therefore, the second embodiment also has the same effect as the first embodiment. In addition, in the second embodiment, the bottom surface processed surface 111b is curved so as to form the same surface as the bottom surface 111 of the recess 110, so that the bottom surface processed surface 111b and the non-processed surface of the bottom surface 111 It is possible to reduce the step and bending angle formed at the boundary of. Therefore, damage to the sealing material 103 housed in the recess 110 can be further suppressed.

In each of the above embodiments, the shape of the recess 110 in which the sealing material 103 is housed is exemplified as an annular shape having a pair of curved portions 110a and a pair of side portions 110b. However, the present invention can be applied to the shape of the recess 110 such as a circular shape, an elliptical shape, a rectangular shape, and a polygonal shape. Further, the present invention can be applied to a structure in which the shape of the recess 110 is not annular, and in short, it can be widely applied to a structure in which the recess 110 is formed across the mating portion 141.

In each of the above embodiments, the frame body 102 is exemplified as a structure in which the frame portion 151 and the flange 120 are integrally molded. However, the frame portion 151 and the flange 120 may be formed as separate members.

In each of the above embodiments, the base portions 105 and 106 having the fins 105A and 106A are exemplified as a structure provided on both the front and back surfaces of the frame body 102. However, the base portions 105 and 106 having the fins 105A and 106A may be provided only on one of the front surface and the back surface of the frame body 102.

In each of the above embodiments, the frame body 102 is exemplified as a structure composed of two divided portions 131 and 132. However, the present invention can be applied to a structure in which the frame body 102 is composed of three or more divided portions.

In each of the above embodiments, examples have been made as a case where the present invention is applied to the power semiconductor module 1. However, the present invention can be widely applied to an electric circuit device in which a circuit body constituting an electric circuit is built in a case.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Each of the above embodiments may be combined or appropriately modified, and other aspects considered within the scope of the technical idea of the present invention are also included within the scope of the present invention.

1 Power semiconductor module 100 Circuit body 101 Case 102 Frame body 103 Sealing material 105, 106 Base part 105A, 106A Fin 110 Recessed part 110a Curved part 110b Side part 111 Bottom surface 111a, 111b Bottom surface to be processed (processed area)
121 Lower side surfaces 121a, 121b Lower inclined surface (non-processed area)
121c Lower side surface to be machined (area to be machined)
122 Upper side surfaces 122a, 122b Upper inclined surface (non-processed area)
122c Upper side surface to be machined (area to be machined)
131, 132 Divided part 132 Divided part 141 Alignment part 161 Bending part 162 Tangent 328, 330 Power semiconductor element 400 Flow path forming body 421 Inner wall surface

Claims (9)

The circuit bodies that make up the electric circuit and
A circuit body accommodating portion formed by casting and accommodating the circuit body, a concave portion accommodating a sealing material, and a mating portion formed corresponding to the facing portions of the upper and lower molds used in the casting. It has, or one, and a case in which the recess is formed across said mating portion,
The recess has a bottom surface and a pair of side surfaces.
The bottom surface and the pair of side surfaces of the recess have a work area and a non-process area, respectively.
On each of the bottom surface and the pair of side surfaces in the work area, the surfaces of the mating portion and the peripheral edge of the mating portion are removed.
Each of the pair of side surfaces in the non-processed region has a pair of inclined surfaces formed so as to sandwich the processed region.
An electric circuit device in which each of the pair of inclined surfaces is inclined in opposite directions from each end toward the work area so that the side surface of the work area is the top surface. In the electric circuit device according to claim 1,
The recess has a pair of curved portions and a pair of side portions connecting the pair of curved portions.
The machined region is an electric circuit device provided in the region of the curved portion. In the electric circuit device according to claim 2,
An electric circuit device in which the bottom surface of the curved portion in the work area is a flat surface from which the mating portion and the peripheral edge of the mating portion are removed. In the electric circuit device according to claim 3,
An electric circuit device in which the bending angle between the tangent line at the boundary between the processed region and the non-processed region and the processed region on the bottom surface is 20 degrees or less. In the electric circuit device according to claim 2,
An electric circuit device in which the bottom surface of the curved portion in the work area is a curved surface from which the mating portion and the peripheral edge of the mating portion have been removed. In the electric circuit device according to claim 1,
The case includes a base portion having fins and a frame portion for holding the base portion.
The frame portion is an electric circuit device having a Young's modulus higher than that of the base portion. In the electric circuit device according to claim 1,
The circuit body is an electric circuit device having a power conversion circuit in which a plurality of power semiconductor elements are mounted. The electric circuit device according to any one of claims 1 to 7.
A flow path forming body having a case accommodating portion for accommodating the case of the electric circuit device and having an inner wall surface facing the recess of the case.
A power conversion device including a sealing material housed in the recess of the case and watertightly closing the inner wall surface of the flow path forming body and the case with respect to the outside. A case having a circuit body accommodating portion for accommodating a circuit body constituting an electric circuit and a recess is formed by casting.
A method for manufacturing a circuit body accommodating case , which comprises removing the surface of a part of the recess of the case after forming the case.
The formation of the case
To form a mating portion corresponding to the facing portion of the upper and lower molds used in the casting, and to form a mating portion.
The recess crosses the mating portion and has a bottom surface and a pair of side surfaces, and each of the pair of side surfaces is provided with the mating portion and a pair of side surfaces provided on both sides of the mating portion with the mating portion interposed therebetween. It comprises forming the recess so that each of the pair of side portions has an inclined surface inclined in a direction with the mating portion as an apex.
Removal of part of the surface of the recess before SL case involves removing the surface of each of said mating portion and該合Se peripheral edge of a portion of the bottom surface and the pair of side surfaces of the recess, the circuit Manufacturing method of body storage case.

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