JPH04332188A - Different insulator integration type metal printed circuit board - Google Patents

Abstract

PURPOSE:To make unnecessary connectors and cables for connecting a plurality of different circuits and space for arranging these parts and to realize reduction in size and simplification of a circuit board by forming a plurality of insulated regions having different characteristics through arrangement of a plurality of kinds of insulators having different characteristics of dielectric constant, dielectric strength and thermal conductivity, etc., on the same plane of a metal plate. CONSTITUTION:A low dielectric constant metal plate 1 having the divided insulating regions and a low thermal resistance metal plate 2 are used. A low electric constant insulator 3 such as glass epoxy mounted in the regions of a metal substrate 1 and a low thermal resistance insulator 4 such as filler epoxy mounted in the regions of a metal substrate 2 are respectively mounted in common with copper foil 5 and metal plate 6 between them and are attached with each other by a vacuum heating press. The substrate 1 and substrate 2 are respectively mounted with different circuits and these circuits are connected with a pattern of copper foil 5. Connector and cable are no longer required and thereby external size of substrates can be reduced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal printed circuit board having a laminated structure of a metal plate, an electrical insulator, and a metal foil.

0002

[Prior Art] As a conventional metal printed circuit board (hereinafter referred to as a metal board), one is known in which one type of electrical insulator is arranged on the same plane of a metal plate. In addition, the circuit component mounting portions are arranged either on one side or only on both sides of the same metal plate, and both are not installed together, and furthermore, they are not shared as the housing of the metal board or its structure. It never happened. Incidentally, FIGS. 3, 6, 8, and 9 respectively show first, second, third, and fourth embodiments of the prior art. First, Figure 3 is an example of a layout diagram when two types of circuits with different operating specifications are mounted on dedicated metal substrates and the two metal substrates are connected with a cable. For example, a low dielectric constant metal substrate 2 is a low thermal resistance metal substrate, 8 is a connector provided on each of the two metal substrates, and 9 is a cable connecting the two connectors. Next, FIG. 6 is a cross-sectional view of the device housing when two types of printed circuit boards with different characteristics are housed in the same case. For example, the low heat resistance metal board 2 and the auxiliary board 10 are fixed to each other with spacers and screws. This figure shows a case in which the metal plate portion of the metal substrate 2 is arranged in close contact with the metal case 11 for heat dissipation. In addition, FIG. 8 shows the metal plate portion of the single-sided mounting type low thermal resistance metal board 2 being connected to the cooling fin 1.
FIG. 9 is a sectional view of the metal substrate when the metal substrate 14 is configured in close contact with the metal substrate 14 of the double-sided mounting type and is fixed to the metal case 11 with screws.

0003

[Problem to be Solved by the Invention] The conventional metal substrate, which uses one type of insulator as described above, is a dedicated and independent board according to the operating specifications of the mounted circuit, such as voltage, frequency, power loss, etc. need to be done. Therefore, the entire device, which has many types of circuit configurations, is relatively small and requires the installation of various types and small quantities of metal substrates. Furthermore, since each metal substrate is installed independently, there is no heat conduction between the metal plates, and therefore, for a metal substrate that generates a large amount of heat due to power loss, heat dissipation measures such as installation of cooling fins are required, resulting in a large external size. Furthermore, regarding the component mounting format of the metal substrate, the single-sided type has good heat dissipation but has a low component mounting rate, while the double-sided type can have a high component mounting rate but has poor heat dissipation and requires special heat dissipation at both ends of the board. Countermeasures are required, and in both cases there are restrictions on reducing the external size. Therefore, the required dimensions of a device housing that commonly accommodates the various metal substrates described above have to increase as the dimensions of each of the metal substrates themselves increase and the space required for connection between the respective substrates increases. Furthermore, as the number of connections between boards increases, the number of connection-related parts such as connectors and cables increases, resulting in a relative decline in operational reliability. In view of the above, the present invention aims to provide a metal printed circuit board integrated with dissimilar insulators, which makes it possible to improve the component mounting rate, improve heat dissipation, simplify the connection between boards, and downsize the device housing case. It is something.

0004

[Means for Solving the Problems] In order to achieve the above object, the metal printed circuit board integrated with different types of insulators of the present invention has a laminated structure of a metal plate, an electrical insulator, and a metal foil such as copper foil. In the metal printed circuit board, a plurality of types of insulators having different characteristics regarding dielectric constant, dielectric strength, thermal conductivity, etc. are arranged on the same plane of the metal plate to form a plurality of insulating regions having different characteristics, Furthermore, a plurality of circuit configurations having different operating specifications such as voltage, frequency, power loss, etc. shall be arranged on the same substrate corresponding to a plurality of insulation regions using the insulating material having appropriately selected characteristics, and furthermore, the thermal A circuit with a large power loss is configured in an insulated area with a low resistance, and a circuit with a small power loss is configured in an insulated area with a higher thermal resistance than the insulated area. Furthermore, the printed circuit board is configured to have two types of component mounting parts, a single-sided part and a double-sided part, and a radiation fin is provided on the single-sided part. The thermal resistance of that part shall be reduced by closely fitting the parts, and the printed circuit board shall be appropriately bent into a box shape or the like, and the printed circuit board shall be used in common with the casing or its structure.

[0005]

[Operation] When circuit components are mounted on a metal substrate, the characteristics of the electrical insulator used for the metal substrate must be compatible with the operating specifications of the circuit. For example, if the circuit voltage is high, use one with high dielectric strength, if the circuit frequency is high, use one with low dielectric constant, and if the power loss of the circuit is large, use one with high thermal conductivity and provide cooling fins. It was necessary to improve the insulation properties along with heat dissipation measures such as the following. This has caused the board to be divided for each circuit type in conventional metal boards that use only one type of electrical insulator.

Therefore, according to the present invention, as the insulator provided between the metal plate and the metal foil of the metal substrate, the insulator is provided on the same plane of the metal plate, regardless of whether it is a single material or a composite material, in terms of its overall insulation properties. By arranging electrical insulators that match the operating specifications of the mounted circuit as areas and forming multiple insulation regions with different characteristics, it is possible to create electrically insulating materials with different operating specifications on the same metal board without having to divide the board as described above. It is possible to install multiple circuits. Therefore, there is no need for inter-board connecting supplies such as connectors and cables as in the case of the prior art. In addition, the temperature in each circuit mounting part is leveled through the metal plate, and even if a part of the circuit includes a large power loss circuit, a local temperature rise can be prevented, and the metal plate is used as a heat sink. Since it also functions as a cooling fin, it is possible to omit or downsize cooling fins. Furthermore, by sharing the metal plate and placing single-sided and double-sided component mounting sections side by side, and by attaching cooling fins to the single side, the component mounting rate and heat dissipation are improved, and the metal board is further miniaturized. Furthermore, by configuring the metal substrate so as to be bendable, the metal plate itself of the substrate can be used in common with the device casing or its structure, thereby making it possible to downsize the device casing.

[0007]

[Example] Hereinafter, the first, second, third, fourth, and fifth of the present invention will be described.
1, 2, 4, 5 and 7 respectively.
I will explain according to. 2 and 3, FIG. 4 and FIG. 8, FIG. 5 and FIG. 6, FIG. 7 and FIG. 8, and FIG. In the figures, components with the same function are given the same reference numerals. First, (a) in Figure 1 is the A-
This is a plan view of a single-sided dissimilar insulator-integrated metal substrate having a cross-sectional configuration as shown in the cross-sectional view of FIG.
This is an example of a case where the substrate is composed of one low dielectric constant metal substrate and two low thermal resistance metal substrates. Further, in FIG. 1B, 3 is a low dielectric constant insulator such as glass epoxy loaded in the area of the metal substrate 1, and 4 is a low heat insulating material such as filler epoxy loaded in the area of the metal substrate 2. They are resistive insulators, and both have a copper foil 5 and a metal plate 6 in common, which are stacked between the two and bonded together using a vacuum heat press. Next, FIG. 2 is an example of a pattern layout diagram when separate circuits are mounted on the substrate 1 and the substrate 2 shown in FIG. 1, and the two circuits are connected by a pattern 7 of copper foil 5. The connector 8 and cable 9 in the corresponding case of FIG. 3 are no longer necessary, and the required external dimensions can be made smaller than the dimensions indicated by dotted lines corresponding to FIG. Next, FIG. 4 is a cross-sectional view of a metal substrate when the substrate 1 is arranged as shown at both ends of the substrate 2 shown in FIG. The smaller of the two is mounted on the substrate 1, and the temperature is leveled by heat transfer via the metal plate 6, and the heat is dissipated by the sum of the areas of the metal plates of each substrate. The cooling fins 13 are omitted. Note that the thermal resistance of the insulation portion of the substrate 1 is greater than that of the substrate 2. In addition, FIG. 5 shows the corresponding FIG. 6
A single metal sheet in which the circuit components mounted on the metal substrate 2 and the auxiliary substrate 10 shown in FIG. This is a cross-sectional view of a metal board mounted on a board and bent 90 degrees at each of the three boundaries of each board to form a structure that also serves as a housing, and the board configuration and housing configuration are significantly different from those in the case of FIG. 6. It has been simplified to . Furthermore, FIG. 7 shows a combination of a single-sided metal substrate 2 having cooling fins 13 and a double-sided metal substrate 14 as shown in FIGS. 12 is arranged and configured by bending each board 90 degrees to form a single metal board that shares the metal plate. It is unnecessary to divide the board as shown in the above two figures, and therefore each board can be placed in its own housing. No installation is required.

[0008]

[Effects of the Invention] According to the present invention, a metal printed circuit board having a laminated structure of a metal plate, an electrical insulator, and a metal foil such as a copper foil has different characteristics in terms of dielectric constant, dielectric strength, thermal conductivity, etc. A plurality of types of insulators are arranged on the same plane of the metal plate to form a plurality of insulating regions with different characteristics, and a plurality of circuit configurations with different operating specifications are formed on the same substrate corresponding to each insulating region. This makes it possible to equalize heat dissipation through a common metal plate, and to allow component mounting sections on one or both sides to be placed side by side on the same metal plate. Or, by sharing the structure, connectors, cables, etc. for connecting multiple circuits and their arrangement space are no longer required, and the required board size is significantly reduced, the internal structure of the storage case is simplified, and the external shape is significantly reduced. It is possible to reduce the size of the device, and furthermore, it is possible to improve the operational reliability due to the simplification of connections between various circuits.

[Brief explanation of drawings]

FIG. 1 is a plan view (a) and a cross-sectional view (b) of a metal substrate integrated with dissimilar insulators showing a first embodiment of the present invention.

FIG. 2 is a pattern layout diagram of a metal substrate integrated with different types of insulators showing a second embodiment of the present invention.

[Fig. 3] Layout diagram of two metal substrates showing the first embodiment of the prior art

FIG. 4 is a cross-sectional view of a metal substrate integrated with dissimilar insulators showing a third embodiment of the present invention.

FIG. 5 is a sectional view of a metal substrate integrated with dissimilar insulators showing a fourth embodiment of the present invention.

[Fig. 6] A sectional view of a device housing showing a second embodiment of the prior art.

FIG. 7 is a cross-sectional view of a metal substrate integrated with dissimilar insulators showing a fifth embodiment of the present invention.

FIG. 8 is a cross-sectional view of a metal substrate showing a third embodiment of the prior art.

FIG. 9 is a cross-sectional view of a metal substrate showing a fourth embodiment of the prior art.

[Explanation of symbols]

1 Low dielectric constant metal substrate 2. Low thermal resistance metal substrate 3 Glass epoxy 4 Filler epoxy 5 Copper foil 6 Metal plate 7 Pattern 8 Connector 9 Cable 10 Auxiliary board 11 Metal case 12 Low dielectric constant double-sided metal substrate 13 Cooling fins 14 Double-sided metal board

Claims (5)

[Claims] Claim 1: A metal printed circuit board having a laminated structure of a metal plate, an electrical insulator, and a metal foil such as copper foil, which has a dielectric constant,
A dissimilar insulator integrated type, characterized in that a plurality of types of the insulators having different characteristics regarding dielectric strength, thermal conductivity, etc. are arranged on the same plane of the metal plate to form a plurality of insulating regions having different characteristics. metal printed circuit board. 2. In the metal printed circuit board integrated with dissimilar insulators according to claim 1, operating specifications such as voltage, frequency, power loss, etc. are adjusted according to a plurality of insulation regions formed by the insulators having appropriately selected characteristics. A metal printed circuit board integrated with dissimilar insulators, characterized in that a plurality of circuit configurations with different characteristics are arranged on the same board. 3. In the metal printed circuit board integrated with dissimilar insulators according to claim 2, the insulating area having a low thermal resistance is provided with a circuit having a large power loss, and the thermal resistance is lower than that of the insulating area. A metal print integrated with dissimilar insulators, characterized in that circuits with small power losses are arranged correspondingly in the large insulation area, and heat dissipation is leveled through the metal plate. substrate. 4. A metal printed circuit board integrated with dissimilar insulators according to claim 2, wherein the printed circuit board has two types of component mounting sections, a single-sided section and a double-sided section, and a radiation fin is provided on the one-sided section. A metal printed circuit board integrated with dissimilar insulators, characterized in that the thermal resistance of that part is reduced by closely fitting the parts. 5. The metal printed circuit board integrated with dissimilar insulators according to claim 1, wherein the printed circuit board is suitably bent into a box shape or the like, and the printed circuit board is shared with a casing or its structure. Metal printed circuit board with integrated insulator.