JP2007294656A - Metal circuit board for high current and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal circuit board for a high current capable of coping with the case of needing a large current, and excellent in voltage resistance, and not only reducing a cost but also reducing a mounting space by half and facilitating mounting by being made into the metal circuit board. <P>SOLUTION: A metal circuit 3 is fitted to the notch 2 of a core member 1 made of a synthetic resin, the core member 1 made of the synthetic resin and the metal circuit 3 are coated with the synthetic resin 4, a metal circuit 5 is formed on the upper surface and/or lower surface of the synthetic resin 4, and a plated through-hole 6 is perforated at a desired position. The metal circuit 3 may be formed in a single layer or a plurality of layers, and the metal circuit 5 may not be provided either. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improvement of a printed circuit board that can cope with a circuit that requires a large current by using a thick metal, has excellent voltage resistance, and can be miniaturized.

  Wiring boards are increasingly required to have higher performance and multi-functionality as their applications spread, but for example, high-current applications such as power supply members for medical equipment, in-vehicle relay boxes, motor control inverters, etc. The demand for a substrate having a high withstand voltage has been remarkably increased, and a substrate capable of downsizing the substrate has been demanded.

However, the conventional thick metal circuit used for the above-mentioned applications, for example, the initial cost of the metal stamping mold and the resin molding mold, such as assembling the stamped metal circuit section on the molded resin insulation part, etc. Therefore, there is a disadvantage that the cost is high even when the circuit needs to be changed.
Edited by Koji Ito, "Printed wiring technology reader", Nikkan Kogyo Shimbun

  The problem to be solved is that a large current circuit part is made into a printed wiring board, so that it can cope with a case where a large current is required, has excellent withstand voltage, and reduces the above-mentioned cost burden. It is another object of the present invention to provide a substrate on which a multi-layered metal circuit is formed which can facilitate the mounting of components and can be miniaturized.

  In order to solve the above-described problems, the present invention proposes the following two means. First, based on a desired circuit design, a metal plate alone is cut or etched into a desired circuit shape, and then an insulating plate having the same thickness as the metal plate circuit is formed on the metal plate circuit. A metal plate circuit is inserted by making it slightly larger (for example, 0.1 to 2 mm) than the planar outer shape. The second means is that an adhesive layer (prepreg) is disposed on both surfaces or one surface of the insulating plate, a metal plate is disposed on the outer surface of the adhesive layer, press-molded, and the metal plate is etched to form a desired circuit. To form.

  As described above, since the conventional large current circuit part is assembled on the resin insulating part formed by molding the punched metal circuit part, for example, the initial cost of the metal punching die, the resin molding die, etc. is large. Needed. Moreover, when the circuit change was required, a high expense was required. By making this large current circuit portion into a printed wiring board, not only the initial cost can be greatly reduced, but also the assembly cost can be reduced by forming the printed wiring board.

  Conventionally, a mounting space is required for each of the large current circuit assembly and the control circuit board. However, by forming a printed wiring board, it is possible to form the same board, so that the mounting space can be reduced to half. Further, by fitting the insulating plate by the thickness of the metal circuit portion, the unevenness of the substrate surface can be suppressed, and the solder resist / component mounting work is facilitated.

  For example, when replacing the solder resist by attaching a clearance processed insulating sheet in the molding press process, the solder resist process at the time of manufacturing the substrate can be omitted, which contributes to cost reduction.

  The metal circuit board for high current according to the present invention can be formed into a plurality of layers as required, so-called thick metal circuit corresponding to high current / high voltage and so-called thin metal circuit corresponding to low current / low voltage. For example, it can be used for various purposes.

  A metal plate is formed into a metal circuit 3 suitable for a desired voltage / current by means of etching, cutting, press punching, electric discharge machining, or the like, and the surface thereof is roughened. As the metal circuit 3, one that can cope with high current and high voltage is mainly selected. Next, the notch 2 that is slightly larger (for example, 0.1 to 2 mm) than the outer shape of the metal circuit 3 in the synthetic resin core member 1 (a thermosetting resin that can be cured) can be selected. And the metal circuit 3 is inserted. Furthermore, the synthetic resin 4 (a thermosetting resin, for example, a B-stage resin can be selected) and a metal foil are joined to the upper surface or the lower surface of the synthetic resin core member 1 and the metal circuit 3, and pressurizing / heating press processing is performed. A plated through hole 6 is drilled at a desired position, and the metal circuit 5 adapted to a desired voltage / current is formed by etching the metal foil. As the metal circuit 5, a metal circuit that can cope with a low current and a low voltage as compared with the metal circuit 3 can be selected. Therefore, the synthetic resin 4 and the metal circuit 5 are coated with a solder resist or other thermosetting resin by printing or other means.

  In the embodiment, the metal circuit 3 capable of handling a high current and a high voltage is formed in a single layer, but in this embodiment, the metal circuit 5 is formed in that the metal circuit 5 is formed in a plurality of layers. It is different in that it does not. That is, not only the metal circuit 3 is inserted into the synthetic resin core member 1, but the synthetic resin 4 is joined to the upper surface or the lower surface thereof to form the circuit member 8, and a plurality of the circuit members 8 are arranged in the vertical direction. The thick metal circuit portion 9 is formed by overlapping, pressing and heating press processing. Therefore, a desired number of plated through holes 6 are drilled at desired positions. In this embodiment, the metal circuit 3 is in contact with a certain plated through hole 6 wall, and the other plated through hole 6 walls are A circuit member 8 that does not contact is formed. In order to cope with this, when not contacting the wall of the plated through hole 6, it should be considered that the synthetic resin is filled in advance or the synthetic resin 4 is melted during the pressurizing / heating press processing. Therefore, the upper and lower surfaces of the thick metal circuit portion 9 are covered with a solder resist or other thermosetting resin 7 by printing or other means.

  In the present embodiment, like the second embodiment, the metal circuit 3 capable of handling high current and high voltage is formed in a plurality of layers unlike the first embodiment. However, the difference from the second embodiment is that the circuit member 8 is A plurality of layers are stacked in the vertical direction to form a thick metal circuit portion 9, and a metal foil is bonded to the upper surface and / or the lower surface of the thick metal circuit portion and pressed and heated and pressed, and the metal foil is etched. The other structure and manufacturing method are the same. In other words, the metal circuit 5 that can cope with a low current and a low voltage is provided as compared with the metal circuit 3 that can cope with a high current and a high voltage.

A metal plate is bonded to the upper and lower surfaces of the synthetic resin core member 1 via an adhesive layer (for example, prepreg is used) and press-molded. The metal plate is formed into the metal circuit 3 by etching, and the synthetic resin is formed. Synthetic resin corresponding to the thickness of the metal circuit 3 is replenished to the upper surface and the lower surface of the core member 1 to be approximately leveled. In this way, the metal circuit 3 and the periphery of the metal circuit 3 are kept level, and since there are no irregularities, component mounting is facilitated, and the use of the metal circuit board is convenient. The synthetic resin 4 and the metal foil are joined to the surface of the metal circuit 3 and the supplementary synthetic resin, pressurized and heated and pressed to form a plated through hole 6 at a desired position, and the metal foil is etched by metal. The circuit 5 is formed, and the synthetic resin 4 and the metal circuit 5 are covered with a solder resist or other thermosetting synthetic resin by printing or other means. Unlike the other embodiments, this embodiment does not take a means for fitting into the cutout portion 2 of the synthetic resin core member 1, so that the thickness of the metal plate that is the object for forming the metal circuit 3 is increased. You can choose.

  The metal circuit board for high current according to the present invention can be bent by removing the synthetic resin covering the metal circuit part even when it is necessary to bend and use the metal circuit board. Can be used for any purpose.

It is a longitudinal cross-sectional view which shows the structure of Example 1 of the metal circuit board for high currents. It is a longitudinal cross-sectional view which shows the structure of Example 2 of the metal circuit board for high currents. It is a longitudinal cross-sectional view which shows the structure of Example 3 of the metal circuit board for high currents. It is a longitudinal cross-sectional view which shows the structure of Example 4 of the metal circuit board for high currents.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Synthetic resin core member 2 Notch part 3 Metal circuit 4 Synthetic resin 5 Metal circuit 6 Plating through hole 7 Solder resist other thermosetting synthetic resin 8 Circuit member 9 Thick metal circuit part

Claims (8)

  The metal circuit 3 is fitted into the notch 2 formed in the synthetic resin core member 1, and the upper surface and the lower surface of the core member 1 and the metal circuit 3 are covered with the synthetic resin 4. Alternatively, a metal circuit 5 is formed on the lower surface, a plated through hole 6 is formed at a desired position, and the synthetic resin 4 and the metal circuit 5 are covered with a solder resist or other thermosetting synthetic resin 7. Metal circuit board for current.   A plurality of circuit members 8 are formed by inserting a metal circuit 3 into a notch 2 formed in a synthetic resin core member 1 and covering the core member 1 and the upper surface or lower surface of the metal circuit 3 with a synthetic resin 4. The thick metal circuit portion 9 is formed by pressurizing and heat-molding pressing in the vertical direction, and a desired number of plated through holes 6 are formed at a desired position, and the upper and lower surfaces of the thick metal circuit portion 9 are formed. A metal circuit board for high current, which is coated with a solder resist or other thermosetting synthetic resin 7.   A plurality of circuit members 8 are formed by inserting a metal circuit 3 into a notch 2 formed in a synthetic resin core member 1 and covering the core member 1 and the upper surface or lower surface of the metal circuit 3 with a synthetic resin 4. A thick metal circuit portion 9 is formed by pressing in a vertical direction and pressing and heat-molding, and a metal circuit 5 is formed on the upper surface and / or the lower surface of the thick metal circuit portion 9, and a desired number is formed at a desired position. A metal circuit board for high current, wherein the plated resin through-hole 6 is formed and the synthetic resin 4 and the metal circuit 5 are covered with a solder resist or other thermosetting synthetic resin 7.   The metal circuit 3 is joined to the upper surface and the lower surface of the synthetic resin core member 1, and the upper surface or the lower surface of the core member 1 and each metal circuit 3 is covered with the synthetic resin 4. A metal circuit 5 is formed on the plate, a plated through hole 6 is formed at a desired position, and the synthetic resin 4 and the metal circuit 5 are covered with a solder resist or other thermosetting synthetic resin 7. Metal circuit board. Forming a metal plate into a metal circuit 3 suitable for a desired voltage / current by means of etching, cutting, press punching, electric discharge machining, etc., and roughening the surface;
A step of drilling a notch 2 that is slightly larger than the outer shape of the metal circuit 3 in the synthetic resin core member 1 and inserting the metal circuit 3;
A step of joining the synthetic resin 4 and the metal foil to the upper surface or the lower surface of the synthetic resin core member 1 and the metal circuit 3 and pressurizing and heating and pressing, and a step of drilling the plated through hole 6 at a desired position;
Forming the metal foil on the metal circuit 5 by etching;
Coating the synthetic resin 4 and the metal circuit 5 with a solder resist or other thermosetting synthetic resin 7 by printing or other means;
The method for producing a high-current metal circuit board according to claim 1, comprising: Forming a metal plate into a metal circuit 3 suitable for a desired voltage / current by means of etching, cutting, press punching, electric discharge machining, etc., and roughening the surface;
A step of drilling a notch 2 that is slightly larger than the outer shape of the metal circuit 3 in the synthetic resin core member 1 and inserting the metal circuit 3;
A step of forming the circuit member 8 by bonding the synthetic resin 4 to the upper surface or the lower surface of the synthetic resin core member 1 and the metal circuit 3;
A step of stacking a plurality of circuit members 8 in the vertical direction and forming a thick metal circuit portion 9 by pressing and heating press;
Drilling a desired number of plated through holes 6 at a desired position;
Coating the upper and lower surfaces of the thick metal circuit portion 9 with a solder resist or other thermosetting synthetic resin 7 by printing or other means;
The method for producing a high-current metal circuit board according to claim 2, comprising: Forming a metal plate into a metal circuit 3 suitable for a desired voltage / current by means of etching, cutting, press punching, electric discharge machining, etc., and roughening the surface;
A step of drilling a notch 2 that is slightly larger than the outer shape of the metal circuit 3 in the synthetic resin core member 1 and inserting the metal circuit 3;
A step of forming the circuit member 8 by bonding the synthetic resin 4 to the upper surface or the lower surface of the synthetic resin core member 1 and the metal circuit 3;
A step of stacking a plurality of circuit members 8 in the vertical direction to form a thick metal circuit portion 9 and bonding a metal foil to the upper surface and / or the lower surface of the thick metal circuit portion 9 and pressurizing and heating press processing; ,
Drilling a desired number of plated through holes 6 at a desired position;
Forming the metal foil on the metal circuit 5 by etching;
Coating the synthetic resin 4 and the metal circuit 5 with a solder resist or other thermosetting synthetic resin 7 by printing or other means;
The method for producing a high-current metal circuit board according to claim 3, wherein: Joining a metal plate to the upper surface and the lower surface of the synthetic resin core 1 via an adhesive layer (for example, using a prepreg), and molding and pressing;
Forming the metal plate in the metal circuit 3 by etching;
A step of replenishing the upper surface and the lower surface of the synthetic resin core 1 with a synthetic resin corresponding to the thickness of the metal circuit 3 and substantially leveling;
A step of joining the synthetic resin 4 and the metal foil to the surface of the metal circuit 3 and the supplementary synthetic resin, and pressurizing and heating press processing;
Forming a plated through hole 6 at a desired position;
Forming the metal foil on the metal circuit 5 by etching;
Coating the synthetic resin 4 and the metal circuit 5 with a solder resist or other thermosetting synthetic resin 7 by printing or other means;
The method for producing a high-current metal circuit board according to claim 4, wherein

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