JP2000196269A - Circuit module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain a high accuracy assembly of a sheet-like elastic member by forming a recess in a radiating face of a heat radiating member which faces an electronic component and having the sheet-like elastic member interposed between the radiating face in the recess of the radiating member and the electronic component. SOLUTION: An electronic component 12 such as CPU is mounted on one surface of a printed wiring board 11, a heat radiating member 13 called 'heat sink' is made to be set facing the electronic component 12 interposing a buffering sheet-like elastic member 14, the radiating member 13 has a mounting part 131 which is mounted on the printed wiring board 11 and fixed by screws 15 to support the radiating member 13 with the board 11, and through-holes 132 are formed in the radiating surface of the radiating member 13 having a recess section and are coupled thermally with the electronic component 12 via the sheet-like elastic member 14. Thus a highly accurate assembly of the sheet-like elastic member 14 can be obtained easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit module suitable for mounting on electronic equipment such as a personal computer (PC).

[0002]

2. Description of the Related Art Recently, in the field of electronic equipment, in order to satisfy demands for miniaturization and high performance, circuit modules designed for high-density mounting are mounted to satisfy the demands. In such a circuit module, an electronic component 2 such as a CPU (Central Processing Unit) is mounted on a printed wiring board 1 as shown in FIG. Member 3 is a heat conductive material,
For example, they are stacked and arranged via a sheet-like elastic body 4 formed of silicon rubber. The heat dissipating member 3 is screwed to the printed wiring board 1 using a screw 5, and when the heat generated from the electronic component 2 is thermally conducted through the sheet-like elastic body 4,
The amount of heat is radiated to the surroundings to thermally control the electronic component 2.

[0003] The sheet-like elastic body 4 also serves as a buffer means for the electronic component 2 and the heat radiating member 3 when the heat radiating member is assembled, and is set in consideration of a heat conduction function and a buffer function to the heat radiating member 3. Is done.

However, in the above-described circuit module, the thickness of the sheet-like elastic body 4 is determined by the tolerance of the height of the electronic component 2, the height of the heat radiating member 3, and the heat applied to the heat radiating member 3. Although it is set in consideration of the conduction characteristics, the gap between the electronic component 2 and the heat radiating member 3 is too small in the assembled state of the heat radiating member 3 due to a manufacturing error of the electronic component 2 and the heat radiating member 3. In this case, the sheet-like elastic body 4 is crushed more than necessary, and a large compressive stress is applied to the electronic component 2 and the heat radiating member 3, which may damage the electronic component 2. Is very troublesome.

In view of this, the height of the electronic component 2 and the heat radiation member 3 are set to have a large tolerance, the thickness of the sheet-like elastic body 4 is set to be large, and the load applied to the electronic component is reduced. It is possible.

However, in the configuration in which the thickness of the sheet-like elastic body 4 is increased, the thermal resistance of the sheet-like elastic body 4 is increased, so that the heat conduction characteristic thereof is reduced, and the electronic component 2 has high efficiency. There is a problem that heat control becomes difficult and the size becomes large.

[0007]

As described above, the conventional circuit module has a problem that it is difficult to assemble the sheet-like elastic body with high accuracy, and the production including the design thereof is very troublesome. .

The present invention has been made in view of the above circumstances, and has been made simple and easy to realize a highly accurate assembly of a sheet-like elastic body, thereby simplifying the manufacturing including design. It is an object of the present invention to provide an intended circuit module.

[0009]

According to the present invention, there is provided a printed wiring board having an electronic component mounted on one surface thereof, and a heat radiation surface which is supported by the printed wiring board and is opposed to the electronic component. A circuit module was provided with a heat radiating member provided with a concave portion, and a sheet-like elastic body interposed between the heat radiating surface having the concave portion of the heat radiating member and the electronic component.

According to the above configuration, when the tolerance of the height of the electronic component and the height of the heat radiation member is changed, the load applied to the sheet-like elastic body is changed accordingly, and the load is reduced. When it becomes larger, the portion of the sheet-like elastic body facing the concave portion of the heat radiating member enters the concave portion of the heat radiating member. Therefore, the sheet-like elastic body is not affected by the manufacturing accuracy of the electronic component and the heat dissipating member, and the compressive stress applied to the electronic component and the heat dissipating member is kept in almost the initial state, and the highly reliable high precision As well as realizing the assembling with high precision, it enables high-precision thermal control of electronic components.

According to the present invention, there is provided a printed wiring board having an electronic component mounted on one surface thereof, and a plurality of through-holes formed in a heat radiation surface opposed to the electronic component. And a heat-dissipating member provided side by side, a heat-dissipating surface of the heat-dissipating member having a plurality of through-holes, and a sheet-like elastic body interposed between the electronic components.

According to the above configuration, when the tolerance of the height of the electronic component and the height of the heat radiating member is changed, the load applied to the sheet-like elastic body is changed accordingly, and the load is reduced. When the size of the heat-dissipating member increases, the portion of the heat-dissipating member of the sheet-like member facing the plurality of through-holes enters the through-holes of the heat-dissipating member. Therefore, the sheet-like elastic body is not affected by the manufacturing accuracy of the electronic component and the heat dissipating member, and the compressive stress applied to the electronic component and the heat dissipating member is kept in almost the initial state, and the highly reliable high precision As well as realizing the assembling with high precision, it enables high-precision thermal control of electronic components.

According to another aspect of the present invention, there is provided a printed wiring board having an electronic component mounted on one surface thereof, and a heat radiating member supported by the printed wiring board and having a heat radiating surface facing the electronic component. And a sheet-like elastic body provided with a concave portion on at least one of the opposing surfaces interposed between the heat radiating surface of the heat radiating member and the electronic component.

According to the above construction, when the tolerance of the height of the electronic component and the height of the heat radiating member is changed, the load applied to the sheet-like elastic body is changed accordingly, and the load is increased. Then, the peripheral wall of the concave portion of the sheet-like elastic body is crushed and enters the concave portion. Therefore, the sheet-like elastic body is not affected by the manufacturing accuracy of the electronic component and the heat dissipating member, and the compressive stress applied to the electronic component and the heat dissipating member is kept in almost the initial state, and the highly reliable high precision As well as realizing the assembling with high precision, it enables high-precision thermal control of electronic components.

According to another aspect of the present invention, there is provided a printed wiring board having an electronic component mounted on one surface thereof, and a heat radiating member supported by the printed wiring board and having a heat radiating surface opposed to the electronic component. And a sheet-like elastic body in which a plurality of through holes are provided in parallel on a facing surface interposed between the heat radiating surface of the heat radiating member and the electronic component.

According to the above configuration, when the tolerance of the height of the electronic component and the height of the heat dissipating member is changed, the load applied to the sheet-like elastic body is changed accordingly, and the load is increased. Then, the peripheral walls of the plurality of through holes of the sheet-like elastic body are crushed and enter the through holes. Therefore, the sheet-like elastic body is not affected by the manufacturing accuracy of the electronic component and the heat dissipating member, and the compressive stress applied to the electronic component and the heat dissipating member is kept in almost the initial state, and the highly reliable high precision As well as realizing the assembling with high precision, it enables high-precision thermal control of electronic components.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a circuit module 10 according to an embodiment of the present invention. An electronic component 1 such as a CPU (Central Processing Unit) is provided on one surface of a printed wiring board 11.
2 is mounted. A heat radiating member 13 called a heat sink is provided on the electronic component 12 of the printed wiring board 11.
Are arranged facing each other with the cushioning sheet-like elastic body 14 interposed therebetween.

The heat radiating member 13 is provided with a mounting portion 131, and the mounting portion 131 is mounted on the printed wiring board 11 and screwed with screws 15 to be supported by the printed wiring board 11. A plurality of through holes 132 are formed side by side on the heat dissipation surface of the heat dissipation member 13, and the plurality of through holes 132 are thermally coupled to the electronic component 12 via the sheet-like elastic body 14. You. These through-holes 132 are formed in a round shape, for example, as shown in FIG.

The sheet-like elastic body 14 is formed of a heat conductive material such as silicon rubber, and its thickness dimension takes into account the tolerance of the height dimension of the electronic component 12 and the height dimension of the heat radiation member 13. Is set.

For example, the circuit module 10 shown in FIG.
As shown in FIG.
To be accommodated. The device body 20 is provided with a keyboard 21, and the keyboard 21 is electrically connected to the circuit module 10. Furthermore, the device body 2
At 0, a liquid crystal display (LCD) 22 is rotatably mounted in the direction of the arrow. The liquid crystal display 22 is electrically connected to the circuit module 10.

The device body 20 includes a cooling fan 23.
The outside air is taken in through the cooling fan 23, and the outside air cools the heat generated in the circuit module 10 inside.

In the above configuration, an electronic component 12 is mounted on the printed wiring board 11, and a heat radiating member 13 is disposed on the electronic component 12 so as to face the electronic component 12 with a sheet-like elastic body 14 interposed therebetween. The heat radiating member 13 has its mounting portion 131 screwed to the printed wiring board 11 using the screw 15, and its heat radiating surface is thermally coupled to the electronic component 12 via the sheet-like elastic body 14. Is done.

Here, in the sheet-like elastic body 14, the tolerance applied to the height dimension of the electronic component 12 and the heat radiating member 13 differs from the design value due to a manufacturing error or the like. That is, when the load increases, the sheet-like elastic body 14 enters the through-holes 132 of the heat-dissipating member 13 at portions facing the plurality of through-holes 132 of the heat-dissipating member 13, and is applied to the electronic component 12 and the heat-dissipating member 13. The resulting compressive stress is kept almost in the initial state. This makes it possible to assemble a highly reliable and highly accurate module using the sheet-like elastic body 14 having a desired size of heat conduction and having a thickness dimension without being affected by the manufacturing accuracy of the electronic component 12 and the heat radiation member 13. It can be realized, and simplification of manufacturing including design can be achieved.

The relationship between the compressive stress and the contact ratio between the sheet-like elastic member 14 and the heat-dissipating surface of the heat-dissipating member 13 is such that even if the load applied to the sheet-like elastic member 14 is the same as shown in FIG. It is experimentally confirmed that the compressibility with respect to the load varies depending on the%, 80%, and 56%.

As described above, the circuit module 10 includes:
An electronic component 12 in which a heat radiating member 13 having a plurality of through holes 132 provided in parallel on a heat radiating surface is mounted on a printed wiring board 11.
, And is thermally coupled via a sheet-like elastic body 14.

According to this, when the tolerance of the height of the electronic component 12 and the height of the heat radiating member 13 is changed,
Accordingly, the load applied to the sheet-like elastic body 14 is changed, and when the load increases, the portion of the sheet-like elastic body 14 facing the plurality of through holes 132 of the heat radiating member 13 And the compressive stress applied to the electronic component 12 and the heat radiating member 13 is kept almost in the initial state. Therefore, after realizing high-precision heat control of the electronic component 12 by the sheet-like elastic body 14, it is possible to assemble with high reliability and high precision without being affected by the manufacturing accuracy of the electronic component 12 and the heat radiation member 13. Mounting can be realized, and simplification of manufacturing including the design can be achieved.

In the above embodiment, the heat radiating member 13 is used.
Although the case where the plurality of through-holes 132 are formed side by side on the heat radiation surface has been described, the present invention is not limited to this, and may be configured as shown in FIGS. 5 to 8, for example. However,
5 to 8, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 5 shows that a plurality of recesses 133 are provided side by side on the heat radiating surface of the heat radiating member 13, and the heat radiating member 13 is connected to the electronic component 12 via the sheet-like elastic body 14. They are arranged so as to be opposed to each other and thermally coupled. As a result, the sheet-like elastic body 14 is
2 and the height difference of the heat dissipating member 13 are varied, and when the applied load increases, the heat dissipating member 1
The portion facing the plurality of concave portions 133 is the heat radiation member 13.
The compressive stress applied to the electronic component 12 and the heat radiating member 13 by entering the plurality of concave portions 133 is kept almost in the initial state. Therefore, similarly to the above embodiment, the electronic component 12
In addition to realizing high-precision heat control of the electronic component 12 and the heat radiation member 13, the assembly is realized with high reliability and high accuracy without being affected by the manufacturing accuracy of the electronic component 12 and the heat radiation member 13. Simplification can be achieved. The recess 133 is formed, for example, in a substantially circular cross section as shown in FIG.

FIG. 7 shows a plurality of slit-shaped concave portions 1.
34 are formed at predetermined intervals on the heat radiation surface of the heat radiation member 13,
The heat dissipating member 13 is assembled such that its heat dissipating surface is opposed to the electronic component 12 via the sheet-like elastic body 14 and is thermally coupled thereto. Thereby, the sheet-like elastic body 14 opposes the concave portion 134 of the heat radiation member 13 when the applied load becomes large due to a change in the tolerance between the height of the electronic component 12 and the height of the heat radiation member 13. The part is
The electronic component 1 penetrates into the concave portion 134 of the heat radiation member 13 and
2 and the compressive stress applied to the heat radiating member 13 are kept almost in the initial state. Accordingly, similarly to the above-described embodiment, after realizing high-precision thermal control of the electronic component 12, the electronic component 1
2 and the heat dissipating member 13 are not affected by the manufacturing accuracy, and the assembling is realized with high reliability and high accuracy.
Simplification of production including design can be achieved.

In the case of the structure shown in FIG. 7, at least one end of the plurality of recesses 134 is
4, the load applied to the sheet-like elastic body 14 increases, and when the sheet-like elastic body 14 is crushed, the air existing in the recess 134 extends from the extended portion to the recess. It is possible to efficiently escape to outside 134, and more effective effects are expected.

FIG. 8 shows that a plurality of recesses 135 are formed radially on the heat radiating surface of the heat radiating member 13 so that
The heat-dissipating surface is provided on the electronic component 12 by a sheet-like elastic body 14.
, And are assembled so as to be thermally coupled with each other by being interposed therebetween. Thereby, the sheet-like elastic body 14 is opposed to the concave portion 135 of the heat radiation member 13 when the applied load becomes large due to a change in the tolerance between the height of the electronic component 12 and the height of the heat radiation member 13. The part enters the concave portion 135 of the heat radiating member 13 and the electronic component 12 and the heat radiating member 1
The compressive stress applied to 3 is kept almost in the initial state. Therefore, similarly to the above-described embodiment, after realizing high-precision thermal control of the electronic component 12, without being affected by the manufacturing accuracy of the electronic component 12 and the heat radiating member 13, a highly accurate high-precision As a result, the assembly including the design can be simplified.

In the structure shown in FIG. 8, at least one of the recesses 135 is formed so as to extend from the sheet-like elastic body 14 in substantially the same manner as in FIG. When the load applied to the sheet-like elastic body 14 is crushed and the sheet-like elastic body 14 is crushed, air existing in the concave portion 135 can efficiently escape from the extended portion to the outside of the concave portion 135, and a more effective effect is expected. You.

The concave portions 133, 134 and 135 formed on the heat radiating surface of the heat radiating member are not limited to a substantially circular cross section, but may be of various shapes including a substantially polygonal cross section. It is possible. The slit shape is not limited to a linear shape or a radial shape, and various other shapes such as a spiral shape can be configured, and the same effect can be expected in any case.

In each of the above embodiments, the heat radiating member 1
In the heat radiation surface of No. 3, the through holes 132 or the concave
4,135 is formed, and the compressive stress of the sheet-like elastic body is
Even if the applied load is changed, the load is made substantially uniform without being affected by the change in the load. However, the present invention is not limited to this, and a plurality of through holes 141 are formed in the sheet-like elastic body 14 as shown in FIG. May be formed side by side.

That is, in the case of FIG. 9, when the tolerance applied to the height of the electronic component 12 and the height of the heat dissipating member 13 is changed and the load applied to the sheet-like elastic body 14 increases, The peripheral wall of the through hole 141 of the elastic body 14 is crushed and enters the through hole 141. Thereby, the compressive stress applied to the electronic component 12 and the heat radiating member 13 of the sheet-like elastic body 14 is kept almost in the initial state without being affected by the manufacturing accuracy of the electronic component 12 and the heat radiating member 13.
While realizing assembly with high accuracy and high reliability,
High-precision heat control of the electronic component 12 is enabled.

Also, a configuration in which a plurality of recesses are formed in the sheet-like elastic body 14 instead of the through-holes 141 in parallel is effective.

Further, the shape of the through-hole 141 or the concave portion formed in the sheet-like elastic body 14 is not limited to a substantially circular cross section, but can be configured using various shapes such as a substantially polygonal cross section.

Accordingly, the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0040]

As described above in detail, according to the present invention, it is possible to easily and easily realize high-precision assembly of a sheet-like elastic body, thereby simplifying the manufacturing including design. An intended circuit module can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a circuit module according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state viewed from the upper surface of FIG. 1;

FIG. 3 is a diagram showing an electronic apparatus on which the circuit module according to the present invention of FIG. 1 is mounted.

FIG. 4 is a characteristic diagram showing a relationship among a load, a compressive stress, a compressibility, and a contact ratio of FIG.

FIG. 5 is a diagram showing a circuit module according to another embodiment of the present invention.

FIG. 6 is a diagram showing a state viewed from the upper surface of FIG. 5;

FIG. 7 is a diagram showing a circuit module according to another embodiment of the present invention.

FIG. 8 is a diagram showing a circuit module according to another embodiment of the present invention.

FIG. 9 is a diagram illustrating a main part of a circuit module according to another embodiment of the present invention.

FIG. 10 is a diagram showing a conventional circuit module.

[Explanation of symbols]

 20 ... device itself. 21 ... Keyboard. 22 ... Liquid crystal display. 23 ... cooling fan. 10 ... circuit module. 11 Printed circuit board. 12 Electronic parts. 13: heat dissipating member. 131 ... Mounting part. 132 ... through-hole. 133, 134, 135 ... concave portions. 14 ... sheet-like elastic body. 141 ... through-hole. 15 ... Screw.

Claims (8)

[Claims] 1. A printed wiring board on which an electronic component is mounted on one surface, and a heat radiating member supported by the printed wiring board and having a concave portion provided on a heat radiating surface facing the electronic component. A circuit module comprising: a heat radiating surface having a concave portion of the heat radiating member; and a sheet-like elastic body interposed between the electronic component. 2. The circuit module according to claim 1, wherein the heat radiating member is provided with a plurality of concave portions arranged in parallel on a heat radiating surface. 3. The circuit module according to claim 1, wherein at least one end of the recess is formed to extend from an outer diameter of the sheet-shaped elastic body. 4. A printed wiring board having an electronic component mounted on one surface thereof, and a plurality of through-holes provided side by side on a heat radiation surface which is supported by the printed wiring board and faces the electronic component. A circuit module, comprising: a heat dissipating member provided in the electronic component; and a heat dissipating member provided between the electronic component and a heat dissipating surface having a plurality of through holes of the heat dissipating member. 5. A printed circuit board having an electronic component mounted on one surface, a heat dissipating member supported by the printed circuit board and having a heat dissipating surface facing the electronic component, A circuit module, comprising: a sheet-like elastic body provided with a concave portion on at least one of opposing surfaces interposed between a heat radiation surface of a member and the electronic component. 6. The circuit module according to claim 5, wherein the sheet-like elastic body is provided with a plurality of concave portions arranged at least on one of the opposing surfaces. 7. A printed wiring board having an electronic component mounted on one surface, a heat dissipating member supported by the printed wiring board and having a heat dissipating surface opposed to the electronic component, A circuit module, comprising: a sheet-like elastic body in which a plurality of through holes are provided side by side on a facing surface interposed between a heat radiation surface of a member and the electronic component. 8. The circuit module according to claim 1, wherein the sheet-like elastic body is formed of a heat conductive material.