JPH11233904A - Printed board having heat radiating structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely and effectively perform heat radiation of electronic component and to substantially reduce the number of item parts in the heat radiating structure and a load of assembling work by laminating and forming a heat radiating layer in a unit on a printed board and by extending a part of the heat radiating layer to the outside of the printed board to make direct contact with the heat radiating layer with a wall part or so on of the chassis. SOLUTION: A printed board 10 on which electronic parts 20 are mounted is provided with a heat radiating layer 11, which radiates heat from the electronic components 20, the heart radiating layer 11 is laminated, and formed at the internal part of the printed board 10, a part of the heat radiating layer 11 is extended from the side surface of the printed board 10 and the extended part has a flexible property. As a result of this, the number of item parts in the heat radiating structure and a load of assembling work can be reduced substantially, and a manufacturing cost 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 heat radiating structure printed circuit board provided with a heat radiating layer for radiating heat of electric components mounted on the board, and more particularly to a heat radiating layer integrally formed on the printed circuit board. By extending a part of the heat radiation layer so as to be drawn out of the printed circuit board, the extended part is brought into direct contact with the wall of the housing or the like, thereby reliably and efficiently dissipating the heat of the electric components. Well done,
The present invention relates to a heat-radiating structure printed circuit board capable of significantly reducing the number of components and the load of assembly work in the heat-radiating structure and reducing manufacturing costs.

[0002]

2. Description of the Related Art Generally, various electric components such as integrated circuits (ICs) and resistors are mounted on a printed circuit board mounted on various electronic devices and the like, and heat generated from these various electric components is generated. It is important to radiate heat efficiently.

Here, a conventional printed circuit board having a heat dissipation structure for electric components will be described with reference to FIGS. 9 and 10. FIG. 9 and 10 are enlarged views of a main part of a state in which a conventional heat dissipation structure printed circuit board is mounted on a housing of an electronic device or the like, where (a) is a plan view and (b) is a partial cross-sectional front view. Is shown.

In these figures, the conventional printed circuit board having a heat dissipation structure shown in FIG. 9 is a printed circuit board 110 mounted on a housing 101 of an electronic device or the like, and the surface (component side) of the printed circuit board is provided with an integrated circuit. Various electric components 120 such as an (IC) and a resistor are mounted on the housing 101.
Are mounted and fixed to the housing 101 via a spacer 102 protruding from the bottom surface of the housing 101 and a bolt 103 screwed to the spacer 102.

A heat radiating plate 130 made of a metal plate is interposed between the printed board 110 and the mounted electric component 120, as shown in FIG. The heat radiating plate 130 is made of a metal plate having excellent thermal conductivity, and is fixed to the bottom surface of the electric component 120 by an adhesive 140.
The printed circuit board 110 is fixed by bolts 103 in a state of being in contact with the surface of the printed circuit board 110 integrally with the electric component 120.

According to the printed circuit board having the heat radiation structure shown in FIG. 9, heat generated from the electric component 120 is transmitted to the heat radiation plate 130 on the bottom surface side of the component, and from there through the spacer 102 to the housing. The heat is conducted to the wall portion 101 and heat is dissipated.

On the other hand, the conventional heat dissipation structure printed circuit board shown in FIG. 10 has substantially the same configuration as that of FIG. 9 described above, and the printed circuit board 210 includes a spacer 202 and a bolt protrudingly provided on the housing 201. 203, the housing 20
1, and various electric components 220 are mounted on the surface.

The printed circuit board 2 shown in FIG.
In 10, a heat radiating plate 230 made of a heat conductive metal plate is disposed on the upper surface of the mounted electric component 120 in a surface contact state, and is fixed via an adhesive 240.
One end side of 30 directly contacts the wall surface of housing 201.

In the printed circuit board having the heat radiation structure shown in FIG. 10, heat from the electric component 220 is transmitted to the heat radiation plate 230 on the upper surface of the component, and is directly conducted to the wall of the housing 201 via the heat radiation plate 230. The heat is dissipated.

A conventional heat dissipation structure of a printed circuit board, which is expected to have a heat dissipation effect by heat conduction by contacting the bottom surface or the top surface of the electric component with a heat dissipation plate made of metal or the like as described above, has been disclosed in Japanese Unexamined Patent Application Publication No. 2002-110,047. 62-617698
No. "Metal-based multilayer printed circuit board", JP-A-63-2
No. 92660, "Multilayer Printed Wiring Board",
Various proposals have been made, such as "Method of Manufacturing Multilayer Printed Wiring Board" in Japanese Patent No. 50489, and "Heat dissipation structure of module" in Japanese Patent Application Laid-Open No. 7-307588.

[0011]

However, in a conventional heat dissipation structure printed circuit board using such a heat dissipation plate,
In each case, in addition to the printed circuit board, it was necessary to separately provide a metal heat sink in contact with the electric components, so that the number of components increased, and the work of mounting and assembling the heat sink and the surface between the heat sink and the electric components were required. Adhesion work or the like in a contact state is required, and assembling work for obtaining a heat dissipation structure becomes extremely complicated, and there is a problem that manufacturing costs increase.

Moreover, in the heat dissipation structure using such a heat dissipation plate, it is necessary to adhere the heat dissipation plate and the electric component using an adhesive, and thus there is a problem in terms of the heat dissipation effect itself. That is, in general, the adhesive has poor heat conductivity, and in a heat dissipation structure in which such an adhesive exists over the entire space between the electric component and the heat radiating plate, the heat is not smoothly conducted by the adhesive portion, and the temperature rises. There was a risk of doing so.

Further, in such a conventional heat dissipation structure,
As long as there is a bonding work process between the heat sink and the electrical component, there is a certain probability that defects due to variations in the bonding state of the bonded parts and the amount of adhesive will occur, and between the electrical component and the heat sink. Therefore, there has been a problem that reliable heat conduction is not performed.

Therefore, the conventional heat dissipating structure in which such a heat dissipating plate and an electric component are bonded by using an adhesive causes a serious problem that a reliable heat dissipating effect cannot be obtained. It has been difficult to apply this method to a high heat-generating component used in a closed housing that mainly emits heat or in a vacuum environment.

The present invention has been proposed in order to solve such problems of the prior art. A heat radiation layer is integrally formed on a printed circuit board, and a part of this heat radiation layer is By extending and forming so as to be drawn out of the printed circuit board, the extended portion of the heat radiation layer is brought into direct contact with the wall of the housing or the like, so that the heat radiation of the electric components can be performed reliably and efficiently, and at the same time, The purpose of the present invention is to provide a printed circuit board having a heat dissipation structure capable of greatly reducing the number of components in the heat dissipation structure and assembling work, and achieving a reduction in manufacturing cost. It is an object of the present invention to provide a heat dissipation structure printed circuit board suitable for a high heat generation component used in a body or under a vacuum environment.

[0016]

According to a first aspect of the present invention, there is provided a printed circuit board on which an electric component is mounted, wherein heat from the electric component is radiated. The heat radiation layer includes at least one heat radiation layer formed on the surface or inside of the printed circuit board, and a part of the heat radiation layer extends from a side surface of the printed circuit board. In Item 2, the heat dissipation layer is formed so as to be integrally laminated with the printed board. In Claim 3, the printed board is formed of a multilayer board, and the heat dissipation layer is formed of the printed board. At least one layer is formed as a surface layer or an inner layer. Further, in claim 4, at least the extended portion of the heat radiation layer is configured to have flexibility.

According to the heat dissipation structure printed circuit board of the present invention having such a configuration, the heat dissipation layer and the printed circuit board are integrally formed by laminating the heat dissipation layer for radiating heat from the electric components on the printed circuit board. This eliminates the need to provide a separate metal plate or the like to obtain a heat dissipation structure, greatly reducing the number of parts and the burden of assembly work.
Unlike the related art, the occurrence of poor adhesion of the metal plate or the like does not occur at all, and a reliable heat dissipation structure for electric components can be obtained.

Then, a part of the heat radiation layer laminated on the printed circuit board is drawn out of the substrate and freely bent, whereby the heat radiation layer can be brought into contact with, for example, a housing of an electronic device. Heat can be conducted to the outside of the board, which has a high heat dissipation effect, and efficient heat dissipation of electrical components can be achieved.The design of the heat dissipation structure and the layout of the printed circuit board can be performed with a high degree of freedom. it can.

According to a fifth aspect of the present invention, there is provided a printed circuit board having a heat dissipation structure, wherein the printed circuit board has a recess in which the electric component is mounted, and the heat dissipation layer is exposed on a bottom surface or a side surface of the recess. I have.

According to the heat-radiating structure printed circuit board of the present invention having such a structure, the printed circuit board having the concave portion for mounting the electric component enables high-density mounting of various components and also allows the heat-radiating layer to be formed on the printed circuit board. By exposing in the concave portion, the heat radiation effect of the heat radiation layer of the present invention can be obtained even in the case of a printed circuit board particularly requiring high-density mounting.

Further, the heat dissipation structure printed circuit board according to claim 6 is configured such that the heat dissipation layer extends from at least two side surfaces of the printed circuit board.

According to the heat dissipation structure printed circuit board of the present invention having such a configuration, the extended portions of the heat dissipation layer can be pulled out in a plurality of directions outside the substrate, and the extension portions are brought into contact with the housing wall around the substrate. As a result, a higher heat radiation effect can be obtained, and the design and arrangement of the printed circuit board can be designed and arranged with a higher degree of freedom.

Further, the heat dissipation structure printed circuit board of the present invention comprises:
Two or more heat dissipation layers may be formed on the printed circuit board. In this case, the heat radiation effect of the electric component can be further enhanced by the two or more heat radiation layers.

Generally, as the thickness of the heat radiation layer increases, the heat radiation effect increases, but on the other hand, as the layer thickness increases, the flexibility of the extended portion decreases. Therefore, by laminating two or more heat radiation layers, it is possible to secure a large layer thickness and obtain a high heat radiation effect without impairing the flexibility of the extended portion.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a heat dissipation structure printed circuit board according to the present invention will be described below with reference to the drawings. First Embodiment First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an enlarged view of a main part of a state in which a heat dissipation structure printed circuit board according to a first embodiment of the present invention is mounted on a housing, (a) is a plan view, and (b) is a partial cross-sectional front view. ing. FIG. 2 is an enlarged cross-sectional view of the heat dissipation structure printed circuit board according to the first embodiment of the present invention shown in FIG.

As shown in these figures, the heat dissipation structure printed circuit board of the present embodiment is a printed circuit board 10 mounted on a housing 1 of an electronic device or the like, and is made of a conductive member as shown in FIG. A plurality of conductive layers (circuit layers) 12 and a plurality of insulating layers 13 made of a glass epoxy material or the like are laminated (the conductive layers 12a, 12b, 12c, 12d and the insulating layer 1).
3a, 13b, 13c, 13d) It is a multilayer substrate.

Here, conductor layers 12a and 12d are laminated on the front surface (component surface) and the back surface (solder surface) of the printed circuit board 10, respectively.
Various electric components 20 such as an integrated circuit (IC) and a resistor are mounted. This printed circuit board 10
As shown in FIGS. 1A and 1B, the housing 1 is mounted and fixed to the housing 1 via a spacer 2 protruding from the bottom surface of the housing 1 and a bolt 3 screwed to the spacer 2. It has become.

In FIG. 1 and FIG. 2, only one non-terminal surface mount component is shown as the electric component 20, but the electric component 20 is not particularly limited to this. It includes a plurality of various electrical components that are widely mounted on the printed circuit board 10 irrespective of the presence or absence, the component shape, and the like.

The printed circuit board 10 of this embodiment is provided with a heat radiating layer 11 as a means for radiating heat generated by the mounted electric component 20. This heat dissipation layer 11
As shown in FIG. 2, is integrally formed on the printed circuit board 10, and in the present embodiment, is formed as one of the inner layers of the printed circuit board 10 constituting the multilayer board. Specifically, as shown in FIG. 2, the heat radiation layer 11 includes the insulating layer 13 b of the printed circuit board 10 and the insulating layer 13.
c, and is located substantially at the center of the inner layer of the printed circuit board 10.

As shown in FIG. 1, the heat radiation layer 11 has one end extending from the side surface of the printed circuit board 10 and being drawn out of the substrate. Here, the extending portion of the heat radiation layer 11 is integrally formed by a conductive member forming the heat radiation layer 11, and has a bendable flexibility. Thereby, the heat radiation layer 11 can freely bend the extended portion and arbitrarily contact the wall surface or the like of the housing 1 as shown in FIG.

As described above, by forming the heat radiation layer 11 integrally as an inner layer of the printed circuit board 10, heat generated from the electric component 20 is conducted to the outside of the printed circuit board 10 by the heat radiation layer 11 as described later. Moreover, the heat is directly radiated to the heat radiating portion such as the housing 1 via the extending portion.

Here, as the material of the heat radiation layer 11, a material which has a high heat radiation effect of heat from the electric component 20 and whose extension portion can be bent freely is adopted. Copper and the like are preferred.

As a method of forming the heat radiation layer 11, the heat radiation layer 11 can be formed integrally with the printed circuit board 10 by one step of a usual method of forming a multilayer printed circuit board. That is, the heat radiation layer 11 is composed of a normal signal layer, a power supply layer,
It is formed in the same manner as the other layers of the printed circuit board 10 such as the ground layer, laminated with these other layers, and pressurized while heating the adhesive disposed between these layers, thereby forming an integrated part with the printed circuit board 10. Can be formed.

Thus, the printed circuit board 1 of this embodiment
0, the heat radiation layer 11 is
Since it is provided integrally with the heat dissipating member 0, there is no need to separately provide a heat dissipating means for the electric component 20 and to assemble it using an adhesive or the like as in the related art.

In the printed circuit board 10 of the present embodiment, the heat radiation layer 11 is formed as an inner layer of the multilayer substrate, but the present invention is not limited to this. For example, the heat radiation layer 11 can be formed on the surface (or back surface) of a single-layer printed circuit board or on the inside, and even in the case of a multi-layer substrate, the heat radiation layer 11 is not formed as an inner layer but on the front surface or back surface of the substrate. They may be stacked.

That is, the heat radiation layer 11 of the present embodiment is integrally formed on the printed circuit board 10 and at least a part of the heat radiation layer 11 extends outside from the side surface of the printed circuit board 10. Good. In the present embodiment, the extended portion of the heat radiation layer 11 is also formed by extending the heat radiation layer 11 in consideration of simplification of manufacturing and the like. Alternatively, as long as it has flexibility, it may be formed separately from the heat radiation layer 11 and connected thereto.

Next, the operation of the printed circuit board having the above-described structure according to the present embodiment will be described. FIG.
As shown in FIG. 1, a printed circuit board 10 incorporated in a casing 1 of various electronic devices and the like is mounted and fixed on the bottom side of the casing 1 via spacers 2 and bolts 3. Since the heat radiation layer 11 extending from the side surface of the printed circuit board 10 has a bendable flexibility, it can be brought into surface contact with the side wall of the housing 1 as shown in FIG.

In this state, when the electric component 20 mounted on the printed board 10 generates heat, the heat is
The heat is transmitted to the heat radiation layer 11 laminated at the center of the substrate by passing through the conductor layer 12 and the insulating layer 13 of No. 0. The heat transmitted to the heat radiating layer 11 is conducted to the outside of the printed circuit board 10 along the heat radiating layer 11, and the case 1 in which the extension of the heat radiating layer 11 is in contact.
And the heat is directly radiated to the housing 1.

Since the printed circuit board 10 is fixed to the housing 1 by the spacer 2, the heat transmitted to the printed circuit board 10 is also radiated to the bottom surface of the housing 1 via the spacer 2.

As described above, according to the heat dissipation structure printed circuit board of the present embodiment, the heat dissipation layer 11 is laminated on the printed circuit board 10, and a part of the heat dissipation layer is formed so as to extend to the outside of the printed circuit board. Therefore, the extended portion of the heat radiation layer 11 can be brought into direct contact with the wall of the housing 1 or the like.

As a result, the electric component 20 mounted on the printed circuit board 10 can reliably and efficiently radiate heat. Particularly, when the electric component 20 is mounted in a closed housing mainly radiating heat by heat conduction, It is suitable for radiating heat from a printed circuit board on which a high heat-generating component used in a vacuum environment is mounted.

Further, since the heat radiation layer 11 is integrally laminated on the printed circuit board 10, it is not necessary to separately provide a heat radiation means as in the related art and to attach it to the substrate side by bonding or the like. The housing 1 can freely extend the heat radiation layer 11.
The heat dissipation structure can be realized only by contacting the contact member.
As a result, the number of components as a heat radiation structure of the electric component 20 and the burden of assembly work can be significantly reduced, and the manufacturing cost can be reduced.

Further, in the present embodiment, a part of the heat radiation layer 11 is drawn out of the substrate and can be freely bent to come into contact with the housing 1 of the electronic device. Can be freely conducted to the outside of the substrate having a high heat radiation effect, an efficient heat radiation effect can be achieved, and the design of the heat radiation structure and the mounting layout of the printed circuit board 10 can be performed with a high degree of freedom. .

[Second Embodiment] Next, a second embodiment of the heat dissipation structure printed circuit board of the present invention will be described with reference to FIG. FIG. 3 is an enlarged sectional view of a heat dissipation structure printed circuit board according to a modified embodiment of the second embodiment of the present invention.

Here, the printed circuit board having a heat dissipation structure according to this embodiment shown in the same drawing is a modified embodiment of the above-described first embodiment, and has a concave portion formed on the component mounting surface of the printed circuit board. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description is omitted.

That is, as shown in FIG. 3, the printed circuit board of the present embodiment has a concave portion 10a on which an electric component 20 is mounted. Then, the heat radiation layer 11 laminated on the printed board 10 is exposed from the bottom of the concave portion 10a.

According to the heat dissipation structure printed circuit board of this embodiment having such a configuration, the heat dissipation layer 11 described in the first embodiment can be applied to the case where the recess 10a is formed in the printed circuit board 10. In particular, even in the case of a printed circuit board requiring high-density mounting, the heat radiation effect by the heat radiation layer 11 of the present invention can be obtained.

In particular, in this embodiment, since the heat radiation layer 11 is exposed at the bottom of the concave portion 10a, the electric component 20 can be brought into direct contact with the heat radiation layer 11, as shown in FIG. As for the heat radiation effect, the heat radiation can be performed more efficiently.

Here, the method of forming the recess 10a is as follows.
For example, a signal layer or power supply layer in which a through hole has been formed in advance,
The heat radiation layer 11 can be formed by laminating the heat radiation layer 11 on another layer, or the printed circuit board 10 on which the heat radiation layer 11 is laminated may be formed by mechanical cutting using a router or the like.

It should be noted that, as in the present embodiment, the printed circuit board 1
0, the heat radiation image 11 is
It is of course possible to laminate the heat radiation layer 11 further below the concave portion 10a without exposing the heat radiation layer 11 to the bottom surface of the concave portion 10a. Further, the heat radiation layer 11 can be exposed on the side surface of the concave portion 10a (see FIG. 8 described later).

[Third Embodiment] Next, a third embodiment of the heat dissipation structure printed circuit board of the present invention will be described with reference to FIGS. FIG. 4 is an enlarged sectional view of a heat dissipation structure printed circuit board according to the third embodiment of the present invention. FIG.
FIG. 8 is an enlarged sectional view of a heat dissipation structure printed circuit board according to a modified embodiment of the third embodiment of the present invention.

Here, the heat dissipation structure printed circuit board according to the present embodiment shown in these figures is a modified embodiment of the first and second embodiments described above, in which a heat dissipation layer laminated and formed as an inner layer of the printed circuit board is printed. It extends outward from two sides of the substrate. Therefore, the same components as those of the first and second embodiments are denoted by the same reference numerals, and detailed description is omitted.

That is, in this embodiment, FIGS.
As shown in FIG. 2, the heat radiation layer 11 is formed so as to extend from two side surfaces (left and right directions in the drawing) of the printed circuit board 10.
Here, as shown in FIG. 4, the printed board 10 in which the heat dissipation layer 11 extends from two side surfaces may be the printed board 10 shown in the first embodiment described above. As shown, the recess 10 shown in the second embodiment
The printed circuit board 10 provided with “a” can also be used.

In the present embodiment, the direction in which the heat radiation layer 11 is drawn is two directions on the side surface of the printed circuit board 10. However, it is needless to say that the direction can be three directions or four directions on the side surface of the printed circuit board 10. is there.

According to the heat-radiating structure printed circuit board of this embodiment having such a configuration, the extending portions of the heat-radiating layer 11 are pulled out in a plurality of directions outside the substrate, so that the plurality of extending portions respectively surround the substrate. It can be brought into contact with the housing wall or the like, and a higher heat radiation effect can be obtained. Further, since the extended portions of the heat radiation layer 11 are drawn out in a plurality of directions, the layout and the like of installing the printed circuit board 10 on the housing 1 can be designed and arranged with a higher degree of freedom.

[Fourth Embodiment] Next, a fourth embodiment of the heat dissipation structure printed circuit board of the present invention will be described with reference to FIGS. FIG. 6 is an enlarged sectional view of a heat dissipation structure printed circuit board according to the fourth embodiment of the present invention. FIG.
FIG. 11 is an enlarged sectional view of a heat dissipation structure printed circuit board according to a modified embodiment of the fourth embodiment of the present invention. Further, FIG.
FIG. 14 is an enlarged cross-sectional view of a heat dissipation structure printed circuit board according to another modified embodiment of the fourth embodiment of the present invention.

Here, the heat dissipation structure printed circuit board according to the present embodiment shown in these figures is a modified embodiment of the first and second embodiments described above. Are formed in two layers as an inner layer. Therefore, the same components as those of the first and second embodiments are denoted by the same reference numerals, and detailed description is omitted.

That is, in the present embodiment, the heat radiation layer 11
However, two layers are formed on the printed circuit board 10 in a laminated manner.
Specifically, in FIG. 6, the printed circuit board 10 of the above-described first embodiment has two heat dissipation layers 11 (heat dissipation layers 11).
a, 11b), and FIGS. 7 and 8 show that the printed circuit board 10 of the above-described second embodiment has two heat dissipation layers 11 (heat dissipation layers 11a, 11b).

In general, as the thickness of the heat radiation layer 11 increases, the heat radiation effect increases, but on the other hand, the larger the layer thickness, the lower the flexibility of the extended portion drawn out of the printed circuit board 10. turn into. Therefore, in the present embodiment, the heat radiation layer 11 is divided into two layers and laminated, so that the total thickness of the two heat radiation layers 11a and 11b is ensured to be large, and at the same time, each of the heat radiation layers 11a and 11b is extended. The flexibility of the parts is not impaired.

Here, in the printed circuit board 10 shown in FIGS. 6 and 7, the heat radiation layer 11 in the first and second embodiments is used.
Another heat dissipation layer 11b is formed under the heat dissipation layer 11a of this embodiment.

On the other hand, in the printed circuit board 10 shown in FIG.
Another heat radiation layer 11a is laminated on the heat radiation layer 11 in the second embodiment (heat radiation layer 11b of the present embodiment). As a result, the upper heat radiation layer 11a in FIG. 8 has an end exposed on the side surface of the concave portion 10a of the printed circuit board 10.

As shown in FIG. 8, heat is applied around the electric component 20 in the concave portion 10a so that the heat radiating layer 11a exposed on the side surface of the concave portion 10a and the electric component 20 are thermally connected. The conductive resin 14 is sealed. Thereby, the heat from the electric component 20 is radiated to the heat radiation layer 11b on the bottom surface side of the concave portion 10a, and also to the heat radiation layer 11a exposed on the side surface side of the concave portion 10a via the heat conductive resin 14. Conduction and heat dissipation.

In this embodiment, as shown in FIGS. 6 to 8, two heat dissipation layers 11 are provided. However, depending on the thickness of the printed circuit board 10 and the number and types of mounted components, etc. Accordingly, it is of course possible to provide three or more layers. By increasing the number of heat radiation layers 11, the heat radiation effect can be further enhanced.

As described above, according to the heat dissipation structure printed circuit board of the present embodiment, the heat dissipation effect of the electric component 20 mounted on the printed circuit board 10 is further enhanced by providing the two (or more) heat dissipation layers 11. be able to. Moreover, by laminating the heat radiation layer 11 into two or more layers, the flexibility of the extended portion of the heat radiation layer 11 is not impaired.
A large heat dissipation effect can be obtained by securing a large layer thickness.

[0065]

As described above, according to the heat dissipation structure printed board of the present invention, a heat dissipation layer is integrally formed on the printed board, and a part of the heat dissipation layer is drawn out of the printed board. By extending the heat dissipating layer, the extended portion of the heat dissipating layer can be brought into direct contact with the wall of the housing or the like, so that the heat of the electric component can be dissipated reliably and efficiently. And the burden of assembly work can be greatly reduced, and manufacturing costs can be reduced.

In particular, according to the present invention, heat can be reliably radiated from the electric parts by heat conduction to the heat radiation layer. It is suitable for.

[Brief description of the drawings]

FIG. 1 is an enlarged view of a main part in a state where a heat dissipation structure printed circuit board according to a first embodiment of the present invention is mounted on a housing;
Is a plan view, and (b) is a partial cross-sectional front view.

FIG. 2 is an enlarged sectional view of a heat dissipation structure printed circuit board according to the first embodiment of the present invention shown in FIG.

FIG. 3 is an enlarged sectional view of a heat dissipation structure printed circuit board according to a modified embodiment of the second embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a heat dissipation structure printed circuit board according to a third embodiment of the present invention.

FIG. 5 is an enlarged sectional view of a heat dissipation structure printed circuit board according to a modified embodiment of the third embodiment of the present invention.

FIG. 6 is an enlarged sectional view of a heat dissipation structure printed circuit board according to a fourth embodiment of the present invention.

FIG. 7 is an enlarged cross-sectional view of a heat dissipation structure printed circuit board according to a modified embodiment of the fourth embodiment of the present invention.

FIG. 8 is an enlarged cross-sectional view of a heat dissipation structure printed circuit board according to another modification of the fourth embodiment of the present invention.

9A and 9B are enlarged views of a main part in a state where a conventional heat dissipation structure printed circuit board is mounted on a housing, wherein FIG. 9A is a plan view and FIG. 9B is a partial cross-sectional front view.

FIG. 10 is an enlarged view of a main part in a state in which another conventional heat dissipation structure printed circuit board is mounted on a housing, (a) is a plan view,
(B) shows a partial cross-sectional front view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 10 Printed circuit board 10a Depression 11 Heat dissipation layer 12 Conductive layer 13 Insulating layer 14 Thermal conductive resin 20 Electric component

Claims (6)

[Claims] 1. A printed circuit board on which an electric component is mounted, comprising a heat radiating layer from which heat from the electric component is radiated, wherein at least one heat radiating layer is formed on or inside the printed circuit board. A heat dissipation structure printed circuit board, wherein a part of the heat dissipation layer extends from a side surface of the printed circuit board. 2. The printed circuit board according to claim 1, wherein the heat dissipation layer is formed integrally with the printed circuit board. 3. The printed circuit board according to claim 1, wherein the printed circuit board comprises a multilayer board, and the heat dissipation layer is formed at least as a surface layer or an inner layer of the printed circuit board. 4. The printed circuit board according to claim 1, wherein at least the extended portion of the heat dissipation layer has flexibility. 5. The heat dissipation structure print according to claim 1, wherein the printed board has a recess in which the electric component is mounted, and the heat dissipation layer is exposed on a bottom surface or a side surface of the recess. substrate. 6. The heat dissipation structure printed circuit board according to claim 1, wherein the heat dissipation layer extends from at least two side surfaces of the printed circuit board.