JP3549257B2 - Conductor forming method for power inverter - Google Patents

Description

[0001]
[Industrial applications]
The present invention provides a power inverter including a plurality of semiconductor power modules each including a semiconductor element and a plurality of conductors formed of a plate-shaped conductive material that interconnects the plurality of semiconductor power modules and passes a large current. The present invention relates to a method for forming a conductor of a converter.
[0002]
[Prior art]
In a power reversing device generally called an inverter having a plurality of semiconductor power modules composed of semiconductor elements, a main circuit is formed by connecting a plurality of semiconductor power modules to each other by a plurality of conductors through which a large current flows. Be composed. The plurality of conductors constituting the main circuit have different outer shapes and outer dimensions from each other, and are formed of a plate-shaped conductive material, and are connected and fixed to each other via an insulator formed of an insulating material. You. Although it is desired that the processing cost incurred in manufacturing each conductor, including the connection and fixing by the insulator, be low, a conventional example of a conductor forming method of a power inverter having such a conductor is shown in FIGS. 4 will be described. FIG. 3 is a plan view showing a configuration of a plurality of conductors according to a conventional conductor shaping method of one power inverter, and FIG. 4 is a plan view showing a configuration of a plurality of conductors according to a conventional conductor shaping method of a different power inverter. In each case, the lower side of the figure is the front side.
[0003]
3 and 4, reference numerals 1A, 1B, and 1C denote a plurality of semiconductor power modules (not shown) provided in the power inversion device, each of which includes a semiconductor element and are connected to each other to allow a large current to flow. A plurality of conductors different from each other.
The plurality of conductors 1A, 1B, and 1C are formed by punching a flat conductive material using a punching die by plastic working. In FIG. 3, a horizontal oblique angle formed from a synthetic resin that is an insulating material is used. Nylon rivets 3 are fixed to the upper surface of the rod-shaped insulator 2 and connected and fixed with a required creepage distance between the surfaces facing each other via air. In FIG. 4, a plurality of conductors 1A, 1B, and 1C are bonded to a flat insulator 4 formed of glass-filled epoxy resin at intervals on the surface of the insulator 4, and have a mutual shape. Different copper foils 5A, 5B, 5C are fixed to each other by means of soldering, etc., and a required creepage distance is provided between the surfaces facing each other via air, and they are electrically separated and physically connected and fixed. Have been.
[0004]
[Problems to be solved by the invention]
By the way, in such a conventional method of forming a conductor of a power inverter, a plurality of conductors 1A, 1B, and 1C, each manufactured by punching using a punching die, are fixed to insulators 2, 4 with rivets 3. Alternatively, they are joined by brazing or the like, and are connected and fixed with a required creepage distance between the surfaces facing each other via air.
[0005]
Thus, it is possible to prevent spark discharge from occurring between the conductors 1A, 1B, and 1C.
However, in manufacturing the conductors 1A, 1B, and 1C, a special punching die is required for each of the conductors 1A, 1B, and 1C, and the conductors 1A, 1B, and 1C are individually attached to the insulators 2 and 4. Need to be fixed to
[0006]
Therefore, the cost for manufacturing and storing and managing the same number of punching dies as the number of the conductors 1A, 1B, 1C required for manufacturing the conductors 1A, 1B, 1C increases, and the conductors 1A, 1B, 1C are made of an insulator. There is a problem that the work of fixing to 2 and 4 is troublesome. The conductors 1A, 1B, 1C are connected and fixed to the insulators 2, 4 with a required creepage distance between the mutually facing surfaces of the conductors 1A, 1B, 1C. Occupies a large space, making it difficult to miniaturize the power inverter.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide a conductor forming method for a power inverter, which can reduce the cost of producing the conductor and can reduce the size of the power inverter.
[0008]
[Means for Solving the Problems]
According to the present invention, to solve the above-described problems, a plurality of semiconductor power modules each including a semiconductor element, and a plurality of conductors formed of a plate-shaped conductive material for connecting the plurality of semiconductor power modules with each other are provided. In a power inverting device provided with, as a first step, a plurality of conductors are punched from a plate-shaped conductive material in a state where a plurality of conductors are connected to each other at a connection portion, and as a second step, a first step A bent portion is formed in the plurality of flat conductors formed in the step, and as a third step, an insulator that physically connects the plurality of conductors formed in the second step to each other is formed, and a fourth step is performed. As a step, the connecting portion is cut off in the third step to electrically separate a plurality of conductors from each other.
[0011]
[Action]
According to the present invention, according to the above configuration, the plurality of conductors formed from one piece of the conductive material integrally with the connecting portion that connects the plurality of conductors to each other are physically connected and fixed to each other via an insulator. Since the connecting portion is cut off and electrically separated from each other, even if the plurality of conductors are a plurality of conductors having different outer shapes and outer dimensions, the plurality of conductors are connected. It can be punched using one punch at a time with the parts connected to each other. Also, even if a conductor having a bent portion is included in a plurality of conductors, a plurality of conductors punched while being connected to each other at a connection portion can be treated as one component, and The bending process can be performed by bending the bent portion with a much smaller number of bending dies than when a plurality of conductors are individually punched using a dedicated punching die.
[0012]
Also, since the insulator is an insulator molded from a synthetic resin, when molding the insulator, a plurality of conductors are inserted into a mold for the insulator to form the insulator. At the same time, a plurality of conductors can be physically connected and fixed to each other by the insulator, and the dielectric strength between the surfaces of the plurality of conductors facing each other via the synthetic resin constituting the insulator can be mutually changed via air. Therefore, the required creepage distance between the surfaces of the plurality of conductors facing each other via the synthetic resin forming the insulator can be reduced.
[0013]
In addition, since the plurality of conductors are physically connected and fixed to each other with this insulator at the same time as the insulator is formed, each of the insulators is riveted or brazed, etc. And the step of connecting and fixing the plurality of conductors to each other can be omitted, and the required creepage distance between the surfaces of the plurality of conductors facing each other via the synthetic resin forming the insulator can be reduced.
[0014]
Further, since the insulator is an insulator in which the support portion for supporting the conductor in the power inverter is integrally formed, it is not necessary to separately manufacture the support portion, and the power inverter is configured. The number of parts can be reduced.
In addition, since the conductor is a conductor having a bent portion formed before being connected and fixed to each other via an insulator, a plurality of conductors punched in a state of being connected to each other at the connection portion are provided. Can be handled as one part, and the bent part is bent with a much smaller number of bending dies than when multiple conductors are manufactured by punching individually using dedicated punching dies. Processing can be performed.
[0015]
【Example】
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a method for forming a conductor of a power inverter according to one embodiment of the present invention, in which (A) and (B) show a plurality of punched-out portions connected to each other at a connecting portion using a punching die. (C) and (D) show a plan view and a right side view of a plurality of conductors in a state where bent portions of the plurality of conductors in the state (A) are bent using a bending mold. In the plan views (E) and (F), the plurality of conductors in the state of (C) are inserted into the mold for forming the insulator, and the plurality of conductors are connected and fixed to each other with the insulator simultaneously with the formation of the insulator. And (G) and (H) show a plurality of conductors in a state in which a connecting portion connecting the plurality of conductors in the state of (E) is cut off using a cutting die. In both the plan view and the right side view, the lower side of the figure is the front side. FIG. 2 is a plan view showing a configuration of a plurality of conductors by a conductor forming method of a power inverter according to a different embodiment of the present invention. The lower side of the figure is the front side. 3 and 4 are denoted by the same reference numerals.
[0016]
In FIG. 1 showing one embodiment of the present invention, 6A, 6B, 6C and 6D in FIGS. 1 (G) and 1 (H) denote a plurality of semiconductor power modules (not shown) constituted by semiconductor elements provided in a power inverter. Are connected to each other to allow a large current to pass through, and a plurality of conductors having mutually different outer shapes and outer dimensions. The plurality of conductors 6A, 6B, 6C, 6D are connected and fixed to each other with a required creepage distance by an insulator 7 molded from a synthetic resin as an insulating material. Among them, the conductors 6A, 6B, 6C have bent portions 8A, 8B, 8C, respectively.
[0017]
The method of forming the plurality of conductors 6A, 6B, 6C, and 6D is as follows. First, as a first step, a punching die is used to connect a flat conductive material to each other at a connecting portion 9 in FIGS. 1A and 1B. The flat conductors 6A, 6B, 6C, 6D without the bent portions 8A, 8B, 8C in the state are punched. Next, as a second step, bent portions 8A, 8B, 8C are simultaneously formed on a plurality of flat conductors 6A, 6B, 6C, 6D formed in the first step by using a bending die, and FIG. A plurality of conductors 6A, 6B, 6C, 6D in the state shown in (C) and (D) are formed. Further, as a third step, the conductors 6A, 6B, 6C, and 6D in which the bent portions 8A, 8B, and 8C are formed in the second step are inserted into a mold for forming the insulator 7, and the insulator 7 is formed. . As a result, the supporting portion 10 supporting the conductors 6A, 6B, 6C, 6D forms an integral insulator 7 in the power inverter, and at the same time, the conductors 6A, 6B, 6C, 6D connected to each other by the connecting portion 9. Are further connected and fixed to each other by an insulator 7 to form a plurality of conductors 6A, 6B, 6C, 6D in the state shown in FIGS. 1 (E) and 1 (F). Finally, as a fourth step, a cutting die for cutting and removing the connecting portions 9 from the conductors 6A, 6B, 6C, and 6D that are connected and fixed to each other by the insulator 7 in the third step and connected to each other by the connecting portions 9 is used. By cutting the connecting portion 9 by using, the required creepage distance is set between the surfaces facing each other via the air and the insulator 7 in the state shown in FIGS. The conductors 6A, 6B, 6C, and 6D that are physically separated and physically connected and fixed by the insulator 7 can be formed.
[0018]
In FIG. 2 showing another embodiment of the present invention, reference numerals 11A, 11B, and 11C denote external shapes and a plurality of semiconductor power modules (not shown) provided in a power inverter, which are connected to each other and pass a large current. It is a plurality of conductors having different external dimensions. The plurality of conductors 11A, 11B, and 11C are fixedly connected to each other at a required creepage distance by an insulator 12 molded from a synthetic resin as an insulating material, and each of the plurality of conductors 11A, 11B, and 11C is broken. It has bent parts 13A, 13B and 13C, respectively.
[0019]
The method of forming the plurality of conductors 11A, 11B, and 11C is substantially the same as that of the embodiment shown in FIG. 1 described above. First, as a first step, a punching die is used to connect a flat conductive material to a connecting portion (not shown). The flat conductors 11A, 11B, and 11C without the bent portions 13A, 13B, and 13C, which are connected to each other, are punched. Next, as a second step, bent portions 13A, 13B, and 13C are simultaneously formed on the plurality of flat conductors 11A, 11B, and 11C formed in the first step using a bending die. Further, as a third step, the conductors 11A, 11B, 11C having the bent portions 13A, 13B, 13C formed in the second step are inserted into a mold for forming the insulator 12, thereby forming the insulator 12. Thereby, the supporting portion 14 supporting the conductors 11A, 11B, 11C forms an integral insulator 12 in the power inverter, and at the same time, further connects the conductors 11A, 11B, 11C connected to each other by a connecting portion (not shown). The insulators 12 are connected and fixed to each other. Finally, as a fourth step, a cutting mold for cutting and removing the conductors 11A, 11B, and 11C which are connected and fixed to each other by the insulator 12 in the third step and connected to each other by a connection part (not shown) is used. Then, the connecting portion (not shown) is cut off. As a result, conductors 11A, 11B, and 11C that are electrically separated from each other with a required creepage distance between the surfaces facing each other through the air and the insulator 12 and that are physically connected and fixed by the insulator 12 can be formed. .
[0020]
In the above-described configuration, the costs associated with the production and storage management of the molds required for producing the conductors 6A, 6B, 6C, 6D and the conductors 11A, 11B, 11C formed by the conductor forming method of the power inverter of the present invention, The processing steps and functions will be described below.
Each of the conductors 6A, 6B, 6C, and 6D and the conductors 11A, 11B, and 11C requires four molds: a punching die, a bending die, a forming die, and a cutting die. Therefore, as compared with the case where the conductors 6A, 6B, 6C and 6D and the conductors 11A, 11B and 11C are manufactured without being connected to each other by the connecting portion 9 and a connecting portion (not shown), the number of molds can be significantly reduced. Costs associated with production and storage management can be significantly reduced.
[0021]
After punching and bending in a state where the connecting portions 9 and a connecting portion (not shown) are connected to each other, the fixing of the insulating members 7 and 12 is performed simultaneously with the formation of the insulators 7 and 12, and , 14 are integrally formed with the insulators 7, 12. Therefore, compared with the case where the conductors 6A, 6B, 6C, 6D and the conductors 11A, 11B, 11C are manufactured without being connected to each other by the connecting portion 9 and the connecting portion (not shown), the conductors 6A, 6B can be processed with significantly less man-hours. , 6C, 6D and conductors 11A, 11B, 11C, and the number of parts can be reduced.
[0022]
Further, the function of the conductors 6A, 6B, 6C, 6D and the conductors 11A, 11B, 11C is to prevent spark discharge between the conductors 6A, 6B, 6C, 6D and between the conductors 11A, 11B, 11C. Can be. At the same time, the strength of the insulator can be improved by the synthetic resin forming the insulators 7 and 12, so that the conductors 6A, 6B, 6C and 6D or the conductors 11A, 11B and 11C facing each other through the synthetic resin can be used. Can be made smaller than the required creepage distance between the surfaces facing each other via air, and the size of the power inverter can be reduced.
[0023]
【The invention's effect】
According to the present invention, a plurality of semiconductor power modules each configured by a semiconductor element are connected to each other, and a plurality of conductors formed of a plate-shaped conductive material are integrally formed with a connecting portion that connects the plurality of conductors. After the conductors are physically connected and fixed to each other via an insulator, the connecting portions are cut off and electrically separated from each other. Therefore, the plurality of conductors have different outer shapes and outer dimensions from each other. Even if conductors are individually punched using dedicated punching dies, punching with a much smaller number of punching and bending dies than when multiple conductors are manufactured The bent portion can be bent at the same time, which has the effect of significantly reducing the cost associated with the production and storage management of the mold and the number of processing steps for the conductor.
[0024]
Also, since the insulator is an insulator molded from a synthetic resin, a plurality of conductors can be physically connected and fixed to each other with the insulator at the same time as the insulator is formed, and the insulator is formed. Facing each other via the synthetic resin, the required creepage distance between the surfaces of the plurality of conductors can be reduced, thereby eliminating the step of physically connecting and fixing the plurality of conductors to each other via the insulator, At the same time, the effect that the power inverter can be downsized can be obtained.
[0025]
In addition, since the plurality of conductors are physically connected and fixed to each other with the insulator at the same time as the formation of the insulator, the step of connecting and fixing the plurality of conductors to each other can be omitted, and the insulator can be formed. The required creeping distance between the surfaces of the plurality of conductors facing each other via the synthetic resin can be reduced, and the same effect as described above can be obtained.
Further, since the insulator is an insulator in which the supporting portion for supporting the conductor is integrally formed in the power inverter, the number of components constituting the power inverter can be reduced, and as a result, This has the effect of reducing the number of man-hours required for manufacturing and assembling the device.
[0026]
In addition, the conductors were formed before being connected and fixed to each other via an insulator, and were conductors having bent portions, so they were individually punched using dedicated punching dies. The bent part can be bent by punching with a much smaller number of punching and bending dies than when multiple conductors are manufactured, thereby reducing the cost associated with the manufacturing and storage management of the die and the man-hours required to process the conductor. Can be greatly reduced.
[0027]
As a result, the cost incurred in the production of the conductor, including the cost in the production and storage management of the mold, can be significantly reduced, and the price and size of the power inverter can be reduced, and the connection part can be reduced. Post-processing such as punching and bending can be performed in a connected and integrated state, so that the effect of facilitating automation of conductor production can be obtained.
[Brief description of the drawings]
FIG. 1 shows a method of forming a conductor of a power inverter according to one embodiment of the present invention, wherein (A) and (B) show a state in which a punching die is used to connect and connect with each other at a connecting portion. A plan view and a right side view of the plurality of conductors, and (C) and (D) are plan views of the plurality of conductors in a state where the bent portions of the plurality of conductors in the state (A) are bent using a bending mold. The right side views, (E) and (F), show a state in which a plurality of conductors in the state of (C) are inserted into a molding die of an insulator, and the insulator is molded and connected to each other with the insulator at the same time. The plan view and the right side view of the plurality of conductors, and (G) and (H) show the plurality of conductors in a state where the connecting portions for connecting the plurality of conductors in the state of (E) are cut off using a cutting die. FIG. 2 is a plan view and a right side view of the present invention. FIG. FIG. 3 is a plan view showing a configuration of a plurality of conductors according to a conventional conductor shaping method of one power inversion device. FIG. 4 is a configuration diagram of a plurality of conductors according to a conventional conductor shaping method of a different power inversion device. [Description of reference numerals]
1A, 1B, 1C, 6A, 6B, 6C, 6D, 11A, 11B, 11C Conductor 2, 4, 7, 12 Insulator 3 Rivet 5A, 5B, 5C Copper foil 8A, 8B, 8C, 13A, 13B, 13C Fold Bending part 9 Connecting part 10, 14 Support part

Claims (1)

In a power inversion device including a plurality of semiconductor power modules configured by semiconductor elements and a plurality of conductors formed of a plate-shaped conductive material for interconnecting the plurality of semiconductor power modules,
As a first step, a plurality of conductors are punched out of a plate-shaped conductive material in a state where a plurality of conductors are connected to each other at a connection portion,
As a second step, forming a bent portion in a plurality of flat conductors molded in the first step,
As a third step, an insulator that physically connects the plurality of conductors having the bent portions formed in the second step to each other is formed,
As a fourth step, a method for forming a conductor of a power reversing device, comprising cutting off a connecting portion in a third step to electrically separate a plurality of conductors from each other .

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