JPH0946007A - Circuit board and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid contact of contaminant to a circuit conductor by preventing clear resin from effusing when an insulation board with a circuit conductor in a prepreg sheet is heated and pressurized. SOLUTION: The device has an insulation board 1A wherein a punched groove is formed to a specified pattern shape and a circuit conductor 3 which has a shape which coincides with a pattern shape and is inserted to the punched groove 9. A prepreg sheet 7 is heated and pressurized at both surface sides of the insulation board 1A to bury the circuit conductor 3 inside the insulation board 1A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board used in devices having a large current capacity power supply and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, there has been proposed a large current circuit board in which a circuit pattern for signals is formed on one surface of an insulating substrate and a circuit conductor for large current is formed on the other surface. This kind of large current circuit board is generally formed by pasting thick copper foil for a large current circuit and pattern etching.

However, in such a large current circuit board, the thickness of the copper foil is limited to a thickness that can be etched. Therefore, in the case of a large current circuit, the conductor width must be increased in order to increase the current capacity. Therefore, it is difficult to make the circuit compact.

When forming a through hole in a circuit conductor for large current, a conductor layer is formed by electroless plating on the inner surface of the hole formed in the insulating substrate, as in the case of a normal signal circuit pattern. However, since it is difficult to increase the thickness of the conductor layer in such a through hole, a large current cannot be passed.

Therefore, many proposals have been made to solve the above inconveniences. FIG. 11 shows, for example, JP-A-63
FIG. 12 is a plan view of a wiring board provided with a large current circuit and a signal circuit described in Japanese Patent Laid-Open No. 237495, and FIG. 12 is a sectional view thereof. In FIG. 12, 1 is an insulating substrate made of glass epoxy or the like.

Further, 2A and 2B are signal circuit conductors provided on the front surface and the back surface of the insulating substrate 1, and 3 is a circuit conductor for large current provided on one surface of the insulating substrate 1.

The circuit conductors 2A and 2B for signals are the same as in the conventional case.
It is formed by etching copper foils used for normal signal circuits attached to both surfaces of the insulating substrate 1 into desired patterns, and the circuit conductors 2A on both surfaces,
A through-hole portion 4 for conducting 2B is also formed on the inner surface of the hole by plating.

On the other hand, as the circuit conductor 3 for large current, for example, a copper plate having a thickness of about 1 mm is punched into a required pattern, and the whole surface is subjected to solder plating or tin plating on the insulating substrate 1. It is formed by soldering.

The through hole portion 5 of the circuit conductor 3 for large current is formed into a cylindrical projection 6 by squeezing out a predetermined portion of the circuit conductor 3 in advance into a cylindrical shape by burring and then forming the cylindrical shape. It is formed by inserting the projection 6 into the hole of the insulating substrate 1.

FIG. 13 is a sectional view showing a conventional high-current circuit board disclosed in Japanese Patent Laid-Open No. 3-21095, in which 7 is a prepreg sheet and 8 is a clear resin. By punching a copper plate or the like, a circuit conductor for large current is formed, and in particular, a punched circuit pattern in which adjacent circuit conductors are connected by a thin bridge is formed.

Here, the prepreg sheet 7 is made by impregnating glass fiber with a thermosetting resin such as epoxy resin and semi-curing it. The prepreg sheet 7 is placed on a prepreg sheet 7 having a plurality of punched circuit patterns laminated and heated. By applying pressure, the prepreg sheet 7 is cured to form an insulating substrate, and a substrate having a punched circuit pattern embedded therein is formed on the insulating substrate. Further, by cutting the bridge portion connecting the adjacent circuit conductors as described above, a circuit board for large current is obtained.

[0012]

Since the conventional large-current circuit board is constructed as described above, in order to increase the current capacity, which is one of the conventional problems, the conductor width must be increased. It can be dealt with by using a copper plate as described above, but since it is fixed to the insulating substrate by soldering, for example, when soldering on the entire surface, the expansion coefficient of the conductor and the substrate during cooling is reduced. There was a problem that warpage might occur due to the difference.

Further, there is a problem that the conductor needs to be subjected to burring for forming the through hole.
Furthermore, since the circuit conductor 3 for large current is soldered on the insulating substrate 1, the solder is projected from the substrate surface,
There is a problem in that the flatness with other signal circuits cannot be obtained, and thus the component mounting by the robot becomes complicated.

On the other hand, according to Japanese Patent Laid-Open No. 3-21095 of FIG. 13, the circuit board is formed by heating and pressurizing the punched circuit conductor and the prepreg sheet 7 with a hot press, so that the surface of the insulating substrate is made flat. Although the problems such as the solder popping out can be solved by such a method, in such a method, the circuit conductor 3 for large current is
Since the prepreg sheet 7 for interlayer insulation is pressed against the circuit conductor 3, the clear resin 8 shown in the figure seeps out from the periphery of the circuit conductor 3 for a large current at the time of pressing, and the temperature rises during energization, so that the circuit conductor 3 and the clear conductor 8 clear. Interface with 8 layers of resin,
Alternatively, there is a problem that cracks may be induced at the interface between the eight layers of clear resin and a circuit conductor (not shown) for signals provided on the surface of the clear resin.

Therefore, with such a method, it is possible to make the surface of the insulating substrate flat, but it is impossible to mix the signal circuit and the large current circuit on the same surface due to the cracks. There is a drawback that

Although not shown in the figure, in this example, a through hole for a large current is formed by plating the inner wall of the conductive hole and then melting and embedding solder in the hole. Since the solder filled in the holes contracts during cooling, there is a risk that the plating layer pre-electrolessly plated on the inner wall of the through hole will peel off.

Further, in order to position the circuit conductors, adjacent circuit conductors are connected by a thin bridge to form a punched circuit pattern. Therefore, the work of cutting the bridge after the lamination molding occurs, and the adverse effect of oxidation of the cut portion occurs. There were problems such as concerns.

The present invention has been made in order to solve the above problems, and does not require troublesome soldering of a circuit conductor to an insulating substrate, and furthermore, heats a punched circuit pattern on a prepreg sheet, (EN) A circuit board that does not seep out of a clear resin during pressurization, avoids contact of contaminants such as dust, water, salt, and gas with a circuit conductor and eliminates electrical defects. With the goal.

Another object of the present invention is to obtain a circuit board on which a multi-layer board for large current can be easily formed similarly to a normal printed wiring board.

Another object of the present invention is to obtain a circuit board in which the creepage distance between circuit conductors on the same insulating substrate can be increased and the insulating characteristics of the circuit conductors can be greatly improved.

Another object of the present invention is to obtain a circuit board which can improve the heat dissipation of the circuit conductor.

Another object of the present invention is to obtain a circuit board which can further enhance the heat dissipation of the circuit conductor.

It is another object of the present invention to obtain a circuit board in which the interlayer distance of the circuit conductors over the respective layers can be shortened, whereby the inductance can be reduced and the structure can be made thin and compact.

Another object of the present invention is to obtain a multi-layer circuit board which is excellent in heat dissipation and which can be easily disassembled and assembled at low cost.

Another object of the present invention is to obtain a circuit board which has a good interlayer insulating property, is easy to disassemble and assemble, and can be formed in a thin shape.

It is another object of the present invention to provide a method for manufacturing a circuit board which can avoid the problems caused by the conventional solder or clear resin and which does not deteriorate due to dust, water, salt, gas, etc. of the circuit conductor.

Further, according to the present invention, a multi-layer circuit board for a large current can be simply and quickly formed in the same manner as an ordinary printed wiring board by simply repeating the step of burying a circuit conductor in an insulating board a plurality of times. The purpose is to obtain a manufacturing method.

Further, according to the present invention, by using a dummy plate to make the circuit conductor portion the same thickness as the insulating substrate, it is possible to heat and press the insulating substrate and the prepreg sheet. An object of the present invention is to obtain a method for manufacturing a circuit board by removing the dummy plate so that the creepage distance between the circuit conductors in the insulating board can be sufficiently secured.

Another object of the present invention is to obtain a method for manufacturing a circuit board, which allows a part of the circuit conductor to be exposed on the insulating board.

Another object of the present invention is to obtain a method for manufacturing a circuit board, in which all the circuit conductors can be exposed on the insulating board.

Another object of the present invention is to obtain a method of manufacturing a circuit board, in which insulating boards having circuit conductors embedded therein can be laminated on both surfaces of a prepreg sheet.

Further, according to the present invention, a single-sided circuit board formed by embedding a circuit conductor in an insulating board and heating and pressurizing it together with a prepreg sheet can be assembled and disassembled simply by connecting them electrically and mechanically via a fastener. An object of the present invention is to obtain a method for manufacturing a multilayer circuit board, which can easily form an easy multilayer circuit board.

Another object of the present invention is to obtain a method for manufacturing a multilayer circuit board in which the insulating characteristics of circuit conductors can be easily secured by using an insulating film.

[0034]

A circuit board according to a first aspect of the present invention has an insulating substrate having a punching groove formed in a predetermined pattern shape and a shape matching the pattern shape, and is inserted into the punching groove. And a prepreg sheet is heated and pressed on both sides of the insulating substrate so that the circuit conductor is embedded in the insulating substrate.

A circuit board according to a second aspect of the present invention comprises an insulating board having a punched groove formed in a predetermined pattern and a circuit conductor having a shape matching the pattern and inserted in the punched groove. A prepreg sheet, which is provided and is heated and pressed together with the insulating substrate, is interposed between the plurality of insulating substrates in which the circuit conductor is inserted into the punching groove.

A circuit board according to a third aspect of the present invention has an insulating substrate having a punching groove formed in a predetermined pattern shape, and a punching groove having a shape matching the pattern shape and being inserted into the punching groove. A circuit conductor thinner than the depth is provided, and the prepreg sheet is heated and pressed together with the insulating substrate so that the circuit conductor is embedded in the punched groove.

A circuit board according to a fourth aspect of the present invention has an insulating substrate having a punching groove formed in a predetermined pattern shape, and a punching groove having a shape matching the pattern shape and being inserted into the punching groove. A circuit conductor thicker than the depth is provided, and a prepreg sheet is laminated on the insulating substrate and heated and pressed so that a part of the circuit conductor is embedded in the punched groove.

A circuit board according to a fifth aspect of the present invention is inserted into a prepreg sheet laminated on an insulating substrate and a punching groove of a dummy plate removed after molding, and is heated and heated together with the insulating substrate on the prepreg sheet. It is provided with the current conductor which is pressed and has the above-mentioned shape in the pattern shape of the punching groove.

A circuit board according to a sixth aspect of the present invention includes an insulating substrate having a punched groove formed in a predetermined pattern shape, and a circuit conductor having a shape matching the pattern shape and inserted in the punched groove. A prepreg sheet that is provided and is heated and pressed together with two single-sided circuit boards composed of the circuit conductor and the insulating board is interposed.

A circuit board according to a seventh aspect of the present invention forms a single-sided circuit board by heating and pressurizing a prepreg sheet together with the insulating board so that the circuit conductor is embedded in the insulating board. Hold multiple sheets at intervals,
The necessary circuit conductors are electrically and mechanically connected by fasteners.

A circuit board according to an eighth aspect of the present invention has a double-sided circuit board formed such that a prepreg sheet is interposed between two single-sided circuit boards composed of a circuit conductor and an insulating substrate, and a plurality of the circuit boards are provided. An insulating film is interposed between the double-sided circuit boards with a predetermined gap, and the necessary circuit conductors are electrically and mechanically connected by fasteners.

According to a ninth aspect of the present invention, there is provided a method of manufacturing a circuit board, wherein a punching groove having a pattern shape of a circuit conductor is formed in an insulating substrate, and the punching groove has a thickness and a shape similar to the depth thereof. After the circuit conductor is inserted, the insulating substrate with the circuit conductor inserted is laminated on a prepreg sheet, and these are heated and pressed together to embed the circuit conductor in the insulating substrate, and then the circuit. A prepreg sheet is laminated on the other surface of the conductor, and the prepreg sheet is heated and pressed onto the insulating substrate.

According to a tenth aspect of the present invention, there is provided a circuit board manufacturing method, wherein a plurality of insulating boards having circuit conductors inserted therein are prepared, and a prepreg sheet is interposed between them.
The prepreg sheet and the insulating substrate are heated and pressed on the insulating substrate.

According to the eleventh aspect of the present invention, there is provided a method of manufacturing a circuit board, wherein a punching groove having a pattern of a circuit conductor is formed in an insulating substrate, and the punching groove has a circuit conductor thinner than a depth of the punching groove and a depth thereof. After inserting a dummy plate with reduced circuit conductor thickness and good releasability, stack the insulating substrate on a prepreg sheet and heat and press them together to embed the circuit conductor in the insulating substrate. Then, the dummy plate is subsequently removed from the punching groove.

According to a twelfth aspect of the present invention, there is provided a method of manufacturing a circuit board, wherein a punched groove having a pattern shape of a circuit conductor is formed in an insulating substrate, and a circuit conductor having a thickness larger than a depth of the punched groove is inserted into the punched groove. After covering the part where the conductor protrudes from the insulating substrate with a punching groove of a dummy plate having good releasability that is equal to the thickness of this part, put a prepreg sheet on the side of the insulating substrate opposite to the covered side. By laminating and heating and pressurizing them together, a part of the circuit conductor is embedded in the insulating substrate, and the dummy plate is separated and removed from the circuit conductor.

According to a thirteenth aspect of the present invention, there is provided a method for manufacturing a circuit board, wherein a prepreg sheet is stacked on an insulating substrate, a dummy plate having a pattern-shaped punching groove of a circuit conductor is stacked on the prepreg sheet, and then the punching is performed. Insert a circuit conductor with a thickness and shape similar to the depth of this into the groove,
Subsequently, the prepreg sheet and the insulating substrate are heated and pressed through the dummy plate to fix the circuit conductor on the prepreg sheet, and then the dummy plate is separated and removed from the circuit conductor. Is.

According to a fourteenth aspect of the present invention, there is provided a circuit board manufacturing method, wherein a single-sided circuit board composed of a circuit conductor and an insulating board is prepared, and a prepreg sheet is interposed between the two single-sided circuit boards to heat each other. By applying pressure, a double-sided circuit board in which the circuit conductor is embedded in the insulating board is prepared.

According to a fifteenth aspect of the present invention, in the method for producing a circuit board, the insulating board in which the circuit conductor is inserted is laminated on the prepreg sheet, and the circuit board is insulated by heating and pressurizing them together. A single-sided circuit board is created by embedding it in a board, and then a plurality of the circuit boards are arranged at regular intervals, and then the circuit conductors are electrically and mechanically connected using fasteners. .

According to a sixteenth aspect of the present invention, there is provided a method for manufacturing a circuit board, wherein the two circuit boards each consisting of a circuit conductor and an insulating board are sandwiched between two single-sided circuit boards with a prepreg sheet interposed therebetween to heat and press the circuit conductor. After creating a double-sided circuit board embedded in an insulating board, and then interposing an insulating film at a predetermined interval between the double-sided circuit boards, the required circuit conductors are electrically and mechanically connected by using a fastener. Are linked together.

[0050]

In the circuit board according to the first aspect of the present invention, since the insulating board in which the circuit conductor is embedded is heated and pressed on both sides so as to be sandwiched by the prepreg sheets, dust, water, salt, gas are added to the circuit conductor. It is possible to prevent direct contact of a fouling material such as, and thereby prevent deterioration of the electrical characteristics of the circuit conductor.

In the circuit board according to the second aspect of the present invention, the single-sided circuit boards are alternately laminated with the prepreg sheets interposed therebetween,
Further, by heating and pressurizing them into an integrated body, they can be used as a large-current multilayer board in the same manner as a multilayer printed wiring board in which a normal prepreg sheet is used.

In the circuit board according to the invention of claim 3, the circuit conductor is housed in the punching groove of the insulating substrate, and the upper surface of the circuit conductor is provided so as to be positioned lower than the upper surface of the insulating substrate. A creeping distance between the insulating substrate and other circuit conductors can be increased to improve the insulation characteristics.

In the circuit board according to the fourth aspect of the present invention, since a part of the circuit conductor is exposed on the insulating substrate, it is possible to improve the heat dissipation of the heat generated in the circuit conductor due to the resistance loss of a large current. .

In the circuit board according to the fifth aspect of the present invention, since the entire circuit conductor is exposed on the insulating substrate, the heat dissipation of the circuit conductor can be further sufficiently improved.

In the circuit board according to the sixth aspect of the present invention, the insulating board in which the circuit conductors are embedded is superposed and integrated via the prepreg sheet as an insulating material, so that the interlayer distance can be shortened and the layers can be connected. When used, the inductance can be reduced and the structure can be thinned.

In the circuit board according to the seventh aspect of the invention, the circuit conductors of the plurality of single-sided circuit boards are detachably connected to each other by fasteners, so that the heat dissipation is excellent, and each circuit is disassembled and assembled. Make it easier.

In the circuit board according to the eighth aspect of the present invention, the double-sided circuit board in which the two single-sided circuit boards are integrated by the insulating film via the prepreg sheet is insulated by the insulating film and the gap. While obtaining the desired interlayer insulation characteristics.

In the method of manufacturing a circuit board according to a ninth aspect of the present invention, by heating and pressurizing both sides of an insulating board in which a circuit conductor is embedded with a prepreg sheet, dust, moisture, salt content on the circuit conductor, It enables the production of circuit boards that can prevent the deterioration of electrical characteristics due to contact with gas or the like.

According to a tenth aspect of the present invention, in a method for manufacturing a circuit board, a prepreg sheet is sandwiched between a plurality of pieces in which circuit conductors are embedded in an insulating board to heat and press,
Enables easy and quick production of multi-layer circuit boards for high power.

According to the eleventh aspect of the present invention, in the method for manufacturing a circuit board, the circuit conductor and the dummy plate are housed in the punching groove of the insulating substrate, and the upper surface of the dummy plate and the upper surface of the insulating substrate are made uniform, so that insulation is achieved. The circuit board and the prepreg sheet are sufficiently heated and pressed to embed the circuit conductor in the punching groove of the insulating board, and after removing the dummy plate, the circuit conductors can secure a sufficient creepage distance in the insulating board.

According to a twelfth aspect of the present invention, in the method of manufacturing a circuit board, a part of the circuit conductor is exposed above the insulating board, and the exposed portion is covered with a punching groove of a dummy plate to form a prepreg sheet. After the lower part of the circuit conductor is embedded in the insulating substrate by heating and pressurizing with the insulating substrate, the dummy plate is removed, so that the circuit conductor exposed on the insulating substrate and having good heat dissipation efficiency can be installed.

In the method of manufacturing a circuit board according to the thirteenth aspect of the present invention, by exposing all the circuit conductors fixed on the insulating substrate on the insulating substrate, the heat dissipation of the circuit conductor can be made more efficient.

According to a fourteenth aspect of the present invention, in the method of manufacturing a circuit board, a circuit conductor is inserted into a punching groove of an insulating board, and a prepreg sheet is interposed between two insulating boards in which the circuit conductor is inserted to heat and pressurize. This makes it possible to easily form a double-sided circuit board.

According to a fifteenth aspect of the present invention, in a method for manufacturing a circuit board, a single-sided circuit board formed by embedding a circuit conductor in an insulating substrate and heating and pressing the prepreg sheet together is formed.
By electrically and mechanically connecting via fasteners, it is possible to easily form a multilayer circuit board that is easy to assemble and disassemble.

In the method for manufacturing a circuit board according to the sixteenth aspect of the present invention, by connecting a plurality of double-sided circuit boards with fasteners through insulating films, a multilayer circuit board having good insulating properties can be formed easily and quickly. To

[0066]

EXAMPLES Example 1. An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 1A is an insulating substrate made of glass epoxy resin or the like, 3 is a circuit conductor for large current embedded in the insulating substrate 1A, and is made of a copper plate having a thickness of about 0.5 to 3.0 mm. .

In this embodiment, for example, 500 to 150
A copper plate having a thickness of 2.3 mm capable of passing a current of 0 A and having a chamfer of a radius of 0.5 mm is used.

The copper plate used as the circuit conductor 3 is a thick copper foil made of electrolytic copper or rolled copper, JIS-C310.
2, flat wire standardized by C3101, etc., or JIS
-C1100, C1220, etc. are standard copper plates.

Reference numeral 7 is a prepreg sheet heated and pressed on both sides of the insulating substrate 1A, and these are integrated to form a large current circuit substrate.

FIG. 2 is a plan view of the insulating substrate 1A which constitutes the large current circuit substrate. The insulating substrate 1A is preliminarily formed with a punching groove 9 having a circuit pattern shape for large current.

FIG. 3 is a plan view showing a situation in which the circuit conductor 3 for large current is inserted into the punching groove 9 shown in FIG.

Next, a method for manufacturing a large current circuit board of the present invention will be described. FIG. 2 shows an insulating substrate 1A in which a punching groove 9 of a large current circuit is formed, and as shown in FIG.
The circuit conductor 3 having the same shape and formed in advance is inserted into the punching groove 9.

On the upper and lower surfaces of the insulating substrate 1A thus constructed, the prepreg sheet 7 which will be an insulating layer after heat curing is laminated. A plurality of prepreg sheets 7 are laminated according to the desired thickness of the surface insulating layer.

If the surface insulating layer is to be thickened,
Another insulating substrate may be prepared in advance, and a prepreg sheet may be sandwiched between the circuit conductor and another insulating substrate to be laminated.

Positioning of the pattern is performed by a pin lamination method using the pins of the jig. For this reason, all of the laminated materials have holes for positioning, and the insulating substrate 1A and the prepreg sheet 7 are stacked and set while passing pins as jigs through the positioning holes (not shown).

Further, in this state, heating and pressurization by hot pressing are performed. For example, heating and pressurization are performed under known press conditions for FR-4.

As a result, the prepreg sheet 7 is cured and becomes a part of the insulating substrate, and the lamination molding process is completed in a state where the circuit conductor 3 is hidden by the insulating substrate 1A to obtain a large current circuit substrate.

In the circuit in which the circuit conductor is mounted by using the prepreg sheet 7, by forming as described above, the clear resin layer formed around the circuit conductor is not generated as in the conventional case, and the mechanical heat is generated. Or due to the heat generated when energized,
It is possible to prevent cracks, peeling, and the like from occurring at the interface between the circuit conductor 3 and the clear resin.

Further, by concealing the circuit conductor 3, contaminants such as dust, moisture, salt and gas do not come into direct contact with the circuit conductor, so that electrical defects due to oxidation of the circuit conductor can be prevented. Furthermore, since the circuit conductor is covered with the insulating substrate, it is excellent in insulating properties from other parts.

Since a circuit for large current is positioned by inserting a circuit conductor having the same thickness into the insulating substrate 1A in which the pattern shape of the circuit conductor 3 is punched out,
Unlike the conventional example, there is no work of cutting the bridge after laminating, and therefore there is no adverse effect due to oxidation of the cut portion. Also, because it is no longer necessary to solder the circuit conductor to the board,
Warpage during cooling can be avoided.

Embodiment 2 FIG. Although the case where one insulating substrate 1A is used is shown in the first embodiment, as shown in FIG. 4, a plurality of insulating substrates 1A, 1B, 1
A circuit board using C and 1D can be used, and in this case, each of the insulating boards 1A to 1D has a punched groove 9 punched in a pattern of a circuit conductor at a predetermined position.

First, the same circuit conductor 3 as that in the above-described embodiment is inserted into each punching groove 9 formed in the insulating substrates 1A to 1D, and the prepreg sheet 7 (this embodiment is used) is inserted between these insulating substrates 1A to 1D. Then, 0.2 mm × 5 sheets are put in to obtain a withstand voltage of 4.5 Kv) and stacked.

Subsequently, in this state, the prepreg sheet 7 is cured by heating and pressurizing with a hot press, and the lamination molding is completed. The large-current circuit board formed in this manner can be used as a large-current multilayer board in the same manner as an ordinary multilayer printed wiring board.

Embodiment 3 FIG. FIG. 5 is a process diagram showing a method of manufacturing a circuit board according to a third embodiment of the present invention. In the figure, reference numeral 10 is a dummy plate made of plastic having good mold release properties. The same parts as those in FIG.
The duplicate description will be omitted.

First, in the punching groove 9 having a circuit pattern shape for a large current formed on the insulating substrate 1A, the circuit conductor 3 thinner than the depth of the punching groove 9 and the thickness of the circuit conductor 3 from the depth of the punching groove 9 are formed. The dummy plate 10 made of a material having a good releasability and having a thickness less than that of the insulating board is inserted to have the same thickness as the insulating substrate.

Next, the insulating substrate 1A is laminated on the prepreg sheet 7, the insulating substrate 1A and the prepreg sheet 7 are heated and pressed to embed the circuit conductor 3 in the insulating substrate 1A, and then the dummy plate is formed. 10 is removed so that the upper surface of the circuit conductor 3 faces the lower part in the insulating substrate 1A.

Since the upper surface of the circuit conductor 3 is formed so as to face the lower part of the insulating substrate 1A, the creeping insulation distance from other circuit conductors on the same insulating substrate 1A can be made longer. The distance from other circuit conductors can be minimized.

In addition, when the circuit board for large current according to this embodiment is used by stacking two circuit boards with the circuit conductors 3 side facing each other, the conductor portions do not contact each other, so that the electrical reliability is improved. To do.

Example 4. 6A to 6C are process diagrams showing another method for manufacturing a circuit board according to the fourth embodiment of the present invention. In this embodiment, the circuit conductor 3 has a shape protruding upward from the upper surface of the insulating substrate 1A.

First, the circuit conductor 3 is formed in the punching groove 9 formed in the insulating substrate 1A and having a circuit pattern shape for a large current. The circuit conductor 3A has a shape thicker than the depth of the punching groove 9.
Insert

Next, the circuit conductor 3A is connected to the insulating substrate 1.
A punching groove 10a is formed on a dummy plate 10A made of plastic having good releasability, which corresponds to the thickness protruding from A, in accordance with the pattern shape of the circuit conductor 3A, and the formed punching groove 10a is formed in the circuit. It is laminated on the upper surface of the insulating substrate 1A so as to be inserted into the conductor 3A, and these are further laminated on the prepreg sheet 7.

Subsequently, the insulating substrate 1A and the prepreg sheet 7 are heated and pressed to attach the circuit conductor 3A to the insulating substrate 1A.
After embedding it inside, the dummy plate 10A is removed. By doing so, the circuit conductor 3A is exposed on the insulating substrate 1A, so that a circuit board having good heat dissipation can be obtained.

Embodiment 5 FIG. 7A to 7D are process diagrams showing a method of manufacturing a circuit board according to a fifth embodiment of the present invention. In this embodiment, the dummy plate 10 made of plastic having good releasing property is used.
The pattern-shaped punched-out groove 10a of the circuit conductor 3 formed in A is placed on the insulating substrate 1A via the prepreg sheet 7, and the pattern-shaped punched-out groove 10a of the circuit conductor 3 formed in the dummy plate 10A. Then, the circuit conductor 3 having the same thickness and shape as the depth of the punched groove 10a is inserted. Subsequently, the dummy plate 10A, the prepreg sheet 7 and the insulating substrate 1A are heated and pressed to form the circuit conductor 3 on the insulating substrate, and then the dummy plate 10A is removed. By doing so, the circuit conductor 3 is exposed on the board, and a circuit board having good heat dissipation can be obtained.

Example 6. 8 is a sectional view showing a circuit board according to a sixth embodiment of the present invention. In this embodiment, first, the circuit conductors 31 and 3 formed on the insulating substrates 1A and 1B.
2 in the pattern-shaped punching groove 9
Circuit conductors 31, 32 having the same thickness and shape as the depth of
Is inserted to form two single-sided circuit boards P.

Next, the insulating substrates 1A and 1B in which the circuit conductors 31 and 32 are inserted are laminated so as to sandwich the prepreg sheet 7, and the insulating substrates 1A and 1B and the prepreg sheet 7 are heated and pressed to heat the circuit conductor 31. , 32 are embedded in the insulating substrates 1A and 1B.

That is, the prepreg sheet 7 is laid on the insulating substrate 1A with the side where the circuit conductor 32 faces the outside facing down, and another insulating substrate is placed with the side where the circuit conductor 31 faces the outside facing up. By laminating 1B, a double-sided circuit board can be formed.

According to this embodiment, the insulating substrate 1A,
By superimposing and integrating the prepreg sheet 7 between 1B, the insulating substrates 1A and 1B and the circuit conductors 31 and 32 are formed.
Can be made into a double-sided board, and the interlayer distance can be shortened by this, and when the circuit conductors 31 and 32 are connected by through holes or fasteners to form a part of an electric circuit, the inductance of the electric circuit is reduced. In addition, the size of the circuit board can be reduced.

Example 7. 9 is a sectional view showing a circuit board according to a seventh embodiment of the present invention. In the figure, 3B, 3
C is a circuit conductor, and 12 is a large current (100A to 50) corresponding to a through hole of an ordinary printed wiring board mounted in a hole 13 penetrating each circuit conductor 3B portion of the insulating substrates 1A and 1B.
It is a fastener for crimping of 0A). The insulating substrate 1
Two caulking fasteners passing through B are connected by the circuit conductor 3C.

Also here, in the punching groove 9 having the pattern shape of the circuit conductor 3B formed on the insulating substrates 1A and 1B,
A circuit conductor 3B having a thickness and a shape similar to the depth of the punched groove 9 is inserted, the insulating substrates 1A and 1B in which the circuit conductor 3B is inserted are laminated on the prepreg sheet 7, and then these The insulating substrates 1A, 1B and the prepreg sheet 7 are heated and pressed to embed the circuit conductors 3B in the insulating substrates 1A, 1B to form the single-sided circuit boards Q, respectively.

By caulking the fasteners 12 to the circuit boards 1A and 1B and connecting the respective fasteners 12, a large current can be passed from the insulating board 1A side to the insulating board 1B side or vice versa. it can.

Here, the insulating substrate 1A and the insulating substrate 1B are fixed via the fastener 12 by a method such as screwing.

According to the method of manufacturing a circuit board of this embodiment, a plurality of insulating boards 1A and 1B are arranged and fixed in the same direction at regular intervals, and the necessary circuit conductors are connected by fasteners 12, so that heat dissipation is improved. Excellent, the single-sided circuit boards Q are easily disassembled independently of each other, and are easy to assemble.

Embodiment 8 FIG. 10 is a sectional view showing a circuit board according to an eighth embodiment of the present invention. In the figure, 11 is an insulating film, and 15 and 15 are gaps between the insulating film 11 and one insulating substrate each on the upper and lower sides. The double-sided circuit board R composed of the insulating boards 1A and 1B was the same as that obtained in Example 6. In this embodiment, an insulating film 11 having a high insulating property is positioned between a plurality of double-sided circuit boards R, and these are combined with a constant gap 15 therebetween.

First, the patterning punched grooves 1c, 1 of the circuit conductors 31, 32 formed on the insulating substrates 1A, 1B.
The circuit conductors 31 and 32 having the same thickness and shape as the depths of the punched grooves 1c and 1d are inserted in d.

The insulating substrates 1A and 1B in which the circuit conductors 31 and 32 are inserted are laminated so as to sandwich the prepreg sheet 7, and the insulating substrates 1A and 1B and the prepreg sheet 7 are heated and pressed. The circuit conductors 31 and 32 are embedded in the insulating substrates 1A and 1B.

That is, the prepreg sheet 7 is laid on the insulating substrate 1A with the side where the circuit conductor 32 faces the outside facing downward, and another insulating substrate is placed on this side with the side where the circuit conductor 31 faces the outside facing upward. By laminating 1B, a double-sided circuit board can be formed.

Then, the double-sided circuit board R formed in this manner is formed, and a plurality of these boards are arranged with a certain gap therebetween with the insulating film 11 interposed therebetween, and the necessary circuit conductors 31 and 32 are connected to each other as described above. By connecting with the same fasteners (not shown) as in Example 7, it is possible to form a circuit board with good heat dissipation that allows the circuits to be independently disassembled and easy to assemble. Further, since the insulating film 11 is arranged between the insulating substrates 1A and 1B, the insulating property between layers becomes excellent.

[0108]

As described above, according to the first aspect of the present invention, an insulating substrate having a punching groove formed in a predetermined pattern shape and a shape matching the pattern shape are inserted into the punching groove. The circuit conductor is provided, and the prepreg sheet is heated and pressed on both sides of the insulating substrate so that the circuit conductor is embedded in the insulating substrate. Without soldering, and without leaching clear resin when heating and pressurizing the prepreg sheet and the punched circuit pattern, and contacting the circuit conductor with contaminants such as dust, water, salt and gas. There is an effect that it is possible to avoid the occurrence of electrical defects by avoiding them.

According to the second aspect of the present invention, there are provided an insulating substrate having a punching groove formed in a predetermined pattern shape, and a circuit conductor having a shape matching the pattern shape and inserted in the punching groove. Since a prepreg sheet which is heated and pressed together with the insulating substrate is interposed between the plurality of insulating substrates in which the circuit conductor is inserted into the punching groove, it can be used for a large current like a normal printed wiring board. There is an effect that the multi-layered substrate can be easily formed.

According to the third aspect of the present invention, an insulating substrate having a punched groove formed in a predetermined pattern shape and a depth of the punched groove which has a shape matching the pattern shape and is inserted into the punched groove are obtained. Since a thin circuit conductor is provided and the prepreg sheet is heated and pressed together with the insulating substrate so that the circuit conductor is embedded in the punching groove, the creepage distance between the circuit conductors on the same insulating substrate can be reduced. It has the effect of being able to lengthen it and greatly improve the insulation characteristics of the circuit conductors.

According to the fourth aspect of the present invention, an insulating substrate having a punching groove formed in a predetermined pattern shape and a depth of the punching groove having a shape matching the pattern shape and being inserted into the punching groove are obtained. A thick circuit conductor is provided, and a part of the circuit conductor is embedded in the punched groove,
Since the prepreg sheet is laminated on the insulating substrate and heated and pressed, the heat dissipation of the circuit conductor can be improved.

According to the fifth aspect of the present invention, the prepreg sheet laminated on the insulating substrate and the dummy plate to be removed after molding are inserted into the punching grooves, and are heated and pressed together with the insulating substrate on the prepreg sheet. In addition, since the circuit conductor formed in the pattern of the punched groove is provided, the heat dissipation of the circuit conductor can be further improved.

According to the invention of claim 6, an insulating substrate having a punched groove formed in a predetermined pattern shape and a circuit conductor having a shape matching the pattern shape and inserted into the punched groove are provided. Between two circuit boards consisting of the circuit conductor and the insulating board, heated together with them,
Since the prepreg sheet to be pressed is interposed, the distance between the two-layer circuit conductors can be shortened, thereby reducing the inductance when connecting and using the two-layer circuit conductors and reducing the structure. This has the effect of making it compact and compact.

According to the invention of claim 7, the prepreg sheet is heated and pressed together with the insulating substrate so that the circuit conductor is embedded in the insulating substrate to form a single-sided circuit substrate. Since a plurality of circuit conductors are held in advance and the necessary circuit conductors are electrically and mechanically connected by fasteners, it is possible to obtain a multilayer board that has excellent heat dissipation, is easy to disassemble and assemble, and is inexpensive. There is.

According to the eighth aspect of the present invention, there is provided a double-sided circuit board formed by interposing a prepreg sheet between two single-sided circuit boards composed of a circuit conductor and an insulating substrate, and a plurality of the double-sided circuit boards. Since an insulating film is interposed with a predetermined gap between the circuit boards and the required circuit conductors are electrically and mechanically connected by fasteners, the interlayer insulation is good, and disassembly and assembly There is an effect that an easy thin multilayer circuit board can be obtained at low cost.

According to the invention of claim 9, a pattern-shaped punching groove of the circuit conductor is formed in the insulating substrate, and the circuit conductor having a thickness and a shape similar to the depth thereof is inserted into the punching groove. After that, the insulating substrate with the circuit conductor inserted therein is laminated on a prepreg sheet, and these are heated and pressed together to embed the circuit conductor in the insulating substrate, and then the other surface of the circuit conductor. Also, since the prepreg sheet is laminated and the prepreg sheet is configured to be heated and pressed on the insulating substrate, it is possible to avoid the troubles caused by the conventional solder or the clear resin, and to prevent dust, water, salt content on the circuit conductor, There is an effect that it is possible to form a circuit board that does not cause deterioration of electrical characteristics due to contact with gas or the like.

According to the tenth aspect of the present invention, a plurality of insulating substrates in which circuit conductors are inserted are prepared, and the prepreg sheet and the insulating substrate are insulated from each other with the prepreg sheet interposed therebetween. Since it is configured to heat and press on the upper surface, by simply repeating the step of embedding the circuit conductor in the insulating substrate multiple times, a multi-layer circuit board for large current can be easily and quickly used like a normal multi-layer printed wiring board. There is an effect that can be formed.

According to the eleventh aspect of the present invention, a punching groove having a pattern shape of the circuit conductor is formed in the insulating substrate, and the punching groove has a circuit conductor thinner than the depth thereof and the thickness of the circuit conductor from the depth. After inserting a dummy plate with good releasability, the insulating substrate is laminated on a prepreg sheet, and the laminate is heated and pressed to embed the circuit conductor in the insulating substrate. Since the dummy plate is configured to be removed, the circuit board portion is made to have the same thickness as the insulating substrate by using the dummy plate, thereby enabling heating and pressurization of the insulating substrate and the prepreg sheet. By removing the dummy plate after the pressurization, there is an effect that a sufficient creepage distance between the circuit conductors in the insulating substrate can be secured and the insulating property can be secured.

According to the twelfth aspect of the present invention, a punching groove having a pattern shape of the circuit conductor is formed in the insulating substrate, and a circuit conductor thicker than the depth thereof is inserted into the punching groove. After covering the protruding part with a punching groove of a dummy plate having a good releasability equal to the thickness of this part, laminate a prepreg sheet on the surface of the insulating substrate opposite to the covered side, and Since a part of the circuit conductor is embedded in the insulating substrate and the dummy plate is removed by heating and pressing together, the part of the circuit conductor can be exposed on the insulating substrate. There is an effect that can be obtained.

According to the thirteenth aspect of the present invention, a prepreg sheet is laid on the insulating substrate, a dummy plate having a punched groove having a pattern of circuit conductors is laid on the prepreg sheet, and then the depth of the punched groove is increased. Insert a circuit conductor having a thickness and shape similar to the above, and then heat the prepreg sheet and insulating substrate through the dummy plate,
Since the dummy plate is removed after fixing the circuit conductor on the prepreg sheet by applying pressure, the whole circuit conductor can be exposed on the insulating substrate to improve the heating effect. effective.

According to the fourteenth aspect of the present invention, a single-sided circuit board composed of a circuit conductor and an insulating substrate is prepared, and a prepreg sheet is interposed between the two single-sided circuit boards to heat and press each other. Since the double-sided circuit board is formed by embedding the circuit conductor in the insulating substrate, there is an effect that the prepreg sheet is obtained by laminating the insulating substrates in which the circuit conductors are embedded on both surfaces.

According to the fifteenth aspect of the present invention, the insulating substrate in which the circuit conductor is inserted is laminated on the prepreg sheet, and the circuit conductor is embedded in the insulating substrate by heating and pressing them together. Since a single-sided circuit board is created and then a plurality of the circuit boards are arranged at regular intervals, the circuit conductors are electrically and mechanically connected using fasteners. The single-sided circuit board, which is formed by embedding the resin in an insulating board and heating and pressing it together with the prepreg sheet, electrically, through a fastener,
There is an effect that a multi-layer circuit board which can be easily assembled and disassembled can be easily formed only by mechanically connecting them.

According to the sixteenth aspect of the present invention, the circuit conductor is embedded in the insulating substrate by interposing a prepreg sheet between two single-sided circuit substrates consisting of the circuit conductor and the insulating substrate, and heating and pressing each other. After making a double-sided circuit board, and then interposing an insulating film at a predetermined distance between the double-sided circuit boards, the necessary circuit conductors are electrically and mechanically connected by fasteners. Since it is configured as described above, there is an effect that the insulating characteristics of the circuit conductors can be easily and surely obtained by using the insulating film.

[Brief description of drawings]

FIG. 1 is a sectional view showing a circuit board according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an insulating substrate in which a punching groove of the large current circuit in FIG. 1 is formed.

FIG. 3 is a plan view showing a situation in which a circuit conductor for large current is inserted into a punching groove in FIG.

FIG. 4 is a sectional view showing a circuit board according to a second embodiment of the present invention.

FIG. 5 is a process drawing showing a method for manufacturing a circuit board according to a third embodiment of the present invention.

FIG. 6 is a process drawing showing a method of manufacturing a circuit board according to a fourth embodiment of the present invention.

FIG. 7 is a process drawing showing a method of manufacturing a circuit board according to a fifth embodiment of the present invention.

FIG. 8 is a sectional view showing a circuit board according to a sixth embodiment of the present invention.

FIG. 9 is a sectional view showing a circuit board according to a seventh embodiment of the present invention.

FIG. 10 is a sectional view showing a circuit board according to an eighth embodiment of the present invention.

FIG. 11 is a plan view showing a conventional circuit board partially broken away.

12 is a cross-sectional view showing the circuit board in FIG.

FIG. 13 is a cross-sectional view showing another conventional circuit board.

[Explanation of symbols]

1A-1D insulating substrate, 3, 3A, 3B, 3C, 31,
32 circuit conductors, 7 prepreg sheets, 9,10a punching grooves, 10,10A dummy plates, 11 insulating films, 12 fasteners, 15 gaps, P, Q single-sided circuit boards, R double-sided circuit boards.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshifumi Kimura 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd.

Claims (16)

[Claims] 1. An insulating substrate having a punched groove formed in a predetermined pattern shape, a circuit conductor having a shape matching the pattern shape and inserted into the punched groove, and the circuit conductor in the insulating substrate. A circuit board having prepreg sheets heated and pressed on both sides of the insulating substrate so as to be embedded. 2. An insulating substrate having a punching groove formed in a predetermined pattern shape, a circuit conductor having a shape matching the pattern shape and being inserted into the punching groove, and the circuit conductor being inserted into the punching groove. A circuit board provided with a prepreg sheet which is sandwiched between the plurality of insulating substrates and which is heated and pressed together with the insulating substrates. 3. An insulating substrate having a punching groove formed in a predetermined pattern shape, a circuit conductor having a shape matching the pattern shape and thinner than the depth of the punching groove inserted into the punching groove, and the circuit. A circuit board comprising: a prepreg sheet that is laminated on the insulating substrate and is heated and pressed together with the insulating substrate so that a conductor is embedded in the punching groove. 4. An insulating substrate having a punching groove formed in a predetermined pattern shape, a circuit conductor having a shape matching the pattern shape and having a thickness larger than the depth of the punching groove inserted in the punching groove, and the circuit. A circuit board comprising: a prepreg sheet laminated on the insulating substrate and heated and pressed together with the insulating substrate so that a part of the conductor is embedded in the punching groove. 5. A pattern of the punching groove, which is inserted into a punching groove of a prepreg sheet laminated on an insulating substrate and a dummy plate which is removed after molding and is heated and pressed together with the insulating substrate on the prepreg sheet. A circuit board having a circuit conductor shaped as described above. 6. An insulating substrate having a punched groove formed in a predetermined pattern shape, a circuit conductor having a shape matching the pattern shape and inserted in the punched groove, the circuit conductor and the insulating substrate. A circuit board including a prepreg sheet which is interposed between two single-sided circuit boards and is heated and pressed together with them. 7. An insulating substrate having a punched groove formed in a predetermined pattern shape, a circuit conductor having a shape matching the pattern shape and inserted in the punched groove, and the circuit conductor in the insulating substrate. A single-sided circuit board formed by heating and pressurizing a prepreg sheet on one side of the insulating board so as to be embedded, and a plurality of the single-sided circuit boards are held at regular intervals to electrically connect the necessary circuit conductors. Circuit board with fasteners that mechanically and mechanically connect. 8. An insulating substrate having a punched groove formed in a predetermined pattern shape, a circuit conductor having a shape matching the pattern shape and inserted in the punched groove, the circuit conductor and the insulating substrate. A double-sided circuit board formed so as to interpose a prepreg sheet between two single-sided circuit boards, an insulating film interposed with a predetermined gap between the plurality of double-sided circuit boards, and the required circuit A circuit board with fasteners that electrically and mechanically connect conductors. 9. A circuit-conductor pattern-shaped punching groove is formed on an insulating substrate, and the circuit conductor having a thickness and shape similar to the depth of the punching groove is inserted into the punching groove, and then the circuit conductor is inserted. The insulating substrate in the state described above is laminated on a prepreg sheet, and the circuit conductor is embedded in the insulating substrate by heating and pressing them together,
Subsequently, a method of manufacturing a circuit board, in which a prepreg sheet is laminated on the other surface of the circuit conductor, and the prepreg sheet is heated and pressed on the insulating substrate. 10. A circuit-conductor pattern-shaped punching groove is formed in an insulating substrate, and the circuit conductor having a thickness and shape similar to the depth of the punching groove is inserted, and then the circuit conductor is inserted. Prepare a plurality of the above-mentioned insulating substrate in the state, and heat the prepreg sheet and the insulating substrate with the prepreg sheet interposed therebetween.
A method of manufacturing a circuit board in which the circuit conductor is embedded in each insulating board by applying pressure. 11. A pattern conductor punching groove is formed on an insulating substrate, a circuit conductor thinner than the depth of the punching groove is formed in the punching groove, and a thickness of the circuit conductor is reduced from the depth of the punching groove. After inserting a good dummy plate, the insulating substrate is laminated on a prepreg sheet, and the circuit conductor is embedded in the insulating substrate by heating and pressing them together, and then the dummy plate is removed from the punching groove. Circuit board manufacturing method. 12. A punching groove having a pattern shape of a circuit conductor is formed on an insulating substrate, a circuit conductor having a thickness larger than the depth of the punching groove is inserted into the punching groove, and the circuit conductor is formed at a portion protruding from the insulating substrate. After covering with a punching groove of a dummy plate having a good releasability equal to the thickness of the part, by laminating a prepreg sheet on the surface of the insulating substrate on the side opposite to this covering side and heating and pressing them together, A method of manufacturing a circuit board, wherein a part of the circuit conductor is embedded in the insulating substrate, and then the dummy plate is removed from the circuit conductor. 13. A prepreg sheet is laminated on an insulating substrate,
After stacking a dummy plate having a pattern-shaped punching groove of a circuit conductor on the prepreg sheet, a circuit conductor having a thickness and shape similar to the depth of the dummy plate is inserted into the punching groove, and then the dummy plate is inserted. A method for manufacturing a circuit board, wherein the dummy conductor is removed from the circuit conductor after the circuit conductor is fixed on the prepreg sheet by heating and pressurizing the prepreg sheet and the insulating substrate via the. 14. A circuit conductor pattern-shaped punching groove is formed in an insulating substrate, and the circuit conductor having a thickness and a shape similar to the depth of the punching groove is inserted into the punching groove. A double-sided circuit board in which the circuit conductor is embedded in the insulating board is created by creating a single-sided circuit board made of an insulating board and heating and pressurizing each other by interposing a prepreg sheet between the two single-sided circuit boards. Method of manufacturing circuit board to be created. 15. A pattern-shaped punching groove of a circuit conductor is formed on an insulating substrate, and the circuit conductor having a thickness and shape similar to the depth of the punching groove is inserted into the punching groove, and then the circuit conductor is inserted. The above-mentioned insulating substrate in the state of being laminated is laminated on a prepreg sheet, and the circuit conductor is embedded in the insulating substrate by heating and pressing them together to form a single-sided circuit substrate, and then the circuit substrate is fixedly spaced. A method for manufacturing a circuit board in which a plurality of circuit conductors are arranged side by side, and the circuit conductors are electrically and mechanically connected to each other by using a fastener. 16. A circuit conductor pattern-shaped punching groove is formed in an insulating substrate, and the circuit conductor having the same thickness and shape as the depth of the punching groove is inserted into the punching groove. The two prepreg sheets are interposed between two single-sided circuit boards made of an insulating substrate to heat each other,
A double-sided circuit board in which the circuit conductor is embedded in the insulating substrate is created by applying pressure, and subsequently, an insulating film is interposed with a predetermined gap between the double-sided circuit boards, and then the required circuit conductors are used together. A method for manufacturing a circuit board, in which a fastener is electrically and mechanically connected to each other.