JP2012146828A - Heat radiation structure and heat radiation member - Google Patents

Abstract

An object of the present invention is to efficiently dissipate heat generated from electronic components inside a casing to the outside of the casing.
A substrate having a first surface disposed inside a housing and facing the inner surface of the housing; an electronic component mounted on the first surface of the substrate; The heat dissipation member 10 is provided between the first surface and the inner surface of the housing 40. The heat dissipation member 10 covers all surfaces except the mounting surface of the electronic component 20, and the first surface of the substrate 30. And the inner surface of the housing 40.
[Selection] Figure 1

Description

  The present invention relates to a heat dissipating structure and a heat dissipating member that dissipate heat generated from electronic components inside a housing.

  Currently, electronic devices are becoming smaller and processing of single electronic components (devices) is increasing due to the aggregation of functions. Electronic components may become dense due to miniaturization of electronic devices, increase in power consumption of electronic components, or decrease in air circulation due to reduction in internal space of the housing. is there. Therefore, when designing an electronic device, it is necessary to take measures to efficiently dissipate the heat generated by the electronic component.

  By providing the fan in the housing, the heat generated by the electronic component can be diffused in the housing. However, if the chassis is installed in a place where it is difficult to replace the fan immediately when the fan fails, such as a base station installed at the top of the utility pole, this method is Not suitable. In addition, it is possible to dissipate heat by providing an opening in a part of the housing, but when the housing is installed outdoors, water drops infiltrate inside the housing due to temperature differences between rain and day and night. This method is not suitable.

  Therefore, as shown in the perspective view of FIG. 6A and the cross-sectional view of FIG. 6B, the heat sink 203 is attached to the electronic component 201 mounted on the substrate 200 via the heat dissipation sheet 202, and the electronic component 201. The heat generated from the heat sink is radiated into the housing, or the electronic component 201 mounted on the substrate 200 is passed through the heat radiating sheet 202 as shown in the perspective view of FIG. 7A and the cross-sectional view of FIG. For example, there is a method of dissipating heat generated from the electronic component 201 by closely contacting the housing 204. Further, as shown in the perspective view of FIG. 8A and the cross-sectional view of FIG. 8B, the substrate 200 is used by utilizing a pattern 205 (signal pattern or ground pattern) on the substrate 200 on which the electronic component 201 is mounted. A method is also conceivable in which heat is transferred and diffused inside to dissipate heat generated from the electronic component 201 into the housing.

  Further, a technique is known in which a heat dissipating sheet in which a plurality of sheets having different thermal conductivities are laminated and laminated on an aluminum sheet is arranged on the upper part of the electronic component, and heat is transferred to the electronic component in a non-contact manner (for example, Patent Document 1).

JP-A-10-256762

  However, since the heat radiation by the heat sink 203 requires a sufficient space for mounting the heat sink 203, the arrangement of the electronic component 201 is restricted, and only the heat radiation into the housing is performed, so the ambient temperature in the housing If is high, the heat dissipation efficiency is poor. In addition, the heat radiation by the heat radiating sheet 202 is not uniform in the distribution of heat generated for each electronic component 201 due to the arrangement and power consumption of the electronic component 201, so the heat of the electronic component 201 may not be efficiently transferred to the housing 204. is there. In addition, heat dissipation using the shape change of the pattern 205 on the substrate 200 can easily move and disperse the heat of the electronic component 201. However, since the heat dissipation destination is inside the housing, there is a problem that a sufficient heat dissipation effect cannot be obtained. is there.

  Moreover, since the heat-radiation sheet of patent document 1 is non-contact with an electronic component, there exists a subject that heat dissipation efficiency is worse than the case where it makes a direct contact with an electronic component.

  An object of the present invention is to provide a heat dissipation structure that can efficiently transfer heat generated from an electronic component to a housing and efficiently dissipate the heat to the outside of the housing without newly requiring a space. And providing a heat dissipation member.

  In order to solve the above-described problems, a heat dissipation structure according to the present invention is a heat dissipation structure that dissipates heat generated from electronic components inside a housing, and is disposed inside the housing and faces the inner surface of the housing. A substrate having a first surface, an electronic component mounted on the first surface of the substrate, and a heat dissipating member tightly sandwiched between the first surface of the substrate and the inner surface of the housing, The heat dissipation member covers all surfaces except the mounting surface of the electronic component, and is in close contact with the first surface of the substrate and the inner surface of the housing.

  Furthermore, in the heat dissipation structure according to the present invention, the heat dissipation member is filled so as to fill a space between the first surface of the substrate and the inner surface of the housing.

  Furthermore, in the heat dissipation structure according to the present invention, an electronic component mounted on the second surface opposite to the first surface of the substrate, and a second heat dissipation disposed on the second surface of the substrate. And the second heat radiating member covers all surfaces except the mounting surface of the electronic component mounted on the second surface of the substrate and is in close contact with the second surface of the substrate. It is characterized by doing.

  Furthermore, the heat dissipation structure according to the present invention further includes a heat dissipation plate disposed in close contact with the second heat dissipation member and joined to the housing.

  Furthermore, in the heat dissipation structure according to the present invention, the second heat dissipation member is filled so as to fill a space between the heat dissipation plate and the second surface of the substrate.

  In addition, the heat dissipation member according to the present invention is a heat dissipation member that is sandwiched between a substrate having an electronic component mounted on one surface and an inner surface of a housing having the substrate inside, and dissipates heat generated from the electronic component. And a recess that covers all surfaces except the mounting surface of the electronic component, a substrate contact surface that is in close contact with one surface of the substrate, and a housing contact surface that is in close contact with the inner surface of the housing. It is characterized by that.

  According to the present invention, the heat radiating member is tightly attached between the substrate and the inner surface of the housing, and the heat radiating member is brought into close contact with not only the electronic component but also the substrate, so that it is generated from the electronic component without requiring a new space. Heat can be efficiently transferred to the housing, and can be efficiently radiated to the outside of the housing.

It is the schematic of the thermal radiation structure which concerns on 1st Embodiment by this invention. It is the schematic of the thermal radiation structure which concerns on 2nd Embodiment by this invention. It is the schematic of the thermal radiation structure which concerns on 3rd Embodiment by this invention. It is the schematic of the thermal radiation structure which concerns on 4th Embodiment by this invention. It is the schematic which shows the modification of the thermal radiation structure which concerns on 4th Embodiment by this invention. It is the schematic of the thermal radiation structure using the heat sink of a prior art example. It is the schematic of the heat dissipation structure using the heat dissipation sheet of a prior art example. It is the schematic of the thermal radiation structure using the board | substrate pattern of a prior art example.

  Hereinafter, embodiments of a heat dissipation structure according to the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic view of a heat dissipation structure according to the first embodiment. Fig.1 (a) is a perspective view of a heat radiating member, FIG.1 (b) is sectional drawing of the heat radiating structure using the heat radiating member shown to Fig.1 (a). The heat dissipation structure 1 includes a housing 40, a substrate 30 disposed inside the housing 40 and having a surface facing the inner surface of the housing 40 (hereinafter referred to as a first surface), and a first of the substrate 30 The electronic component 20 mounted on the surface, and the heat radiating member 10 (10a to 10e) narrowly attached between the first surface of the substrate 30 and the inner surface of the housing 40 are provided. The heat radiating member 10 has a substrate contact surface 101, a recess 102, and a housing contact surface 103.

  The substrate contact surface 101 is in close contact with the first surface of the substrate 30 and conducts heat of the electronic component 20 to the substrate 30. The recess 102 is provided in accordance with the shape of the electronic component 20 and covers all surfaces except the mounting surface of the electronic component 20 (the surface that is in close contact with the first surface of the substrate 30) without a gap. The housing contact surface 103 is in close contact with the inner surface of the housing 40 and conducts heat of the electronic component 20 to the housing 40. The arrows in the figure indicate the heat flow.

  Here, the heat dissipating member 10 is molded by a method of making a rubber mold by pouring a heat dissipating material such as silicone onto a substrate 30 put in a mold, or a method of creating and making an aluminum mold that matches the unevenness of the substrate 30. The

  The heat radiating member 10 may have a shape that covers all surfaces except the mounting surface of the electronic component 20 and is in close contact with the first surface of the substrate 30 and the inner surface of the housing 40. FIG. The shape of the heat radiating member 10a shown in FIG. For example, the shape of the heat radiating member 10 can also be made into the shape as shown to FIG.1 (c)-(g).

  The heat radiating member 10b shown in FIG. 1C increases the area of the housing contact surface 103, increases the contact area between the housing contact surface 103 and the inner surface of the housing 40, and increases the thermal conductivity with respect to the housing 40. Is an improvement. The heat radiating member 10c shown in FIG. 1D widens the area of the substrate contact surface 101, increases the contact area between the substrate contact surface 101 and the first surface of the substrate 30, and increases the thermal conductivity with respect to the substrate 30. It is an improvement. The heat radiating member 10d shown in FIG. 1 (e) increases the area of the housing contact surface 103 and the substrate contact surface 101, and the contact area between the housing contact surface 103 and the inner surface of the housing 40, and the substrate contact surface. 101 and the first surface of the substrate 30 are in close contact with each other, and the thermal conductivity of the housing 40 and the substrate 30 is improved.

  Further, as shown in FIG. 1 (f), when the distance between the substrate 30 and the housing 40 is wide, the housing protrusion 41 is provided on the inner surface of the housing 40 facing the electronic component 20. Without increasing the thickness between the body contact surface 103 and the recess 102, the housing contact surface 103 can be brought into close contact with the housing protrusion 41 and can be thermally conducted to the housing 40. The heat dissipation structure 1 shown in FIG. 1 (f) uses the heat dissipation member 10a shown in FIGS. 1 (a) and 1 (b), but the area of the substrate adhesion surface 101 as shown in FIG. 1 (d). Of course, the heat dissipating member 10c may be used.

  Further, FIGS. 1B to 1F described above show the heat dissipation structure 1 that dissipates heat from one electronic component 20, but a heat dissipation structure that dissipates a plurality of electronic components 20 by providing a plurality of recesses 102. It can also be. For example, the heat radiating member 10e shown in FIG. 1 (g) has two recesses 102, each recess 102 is provided in accordance with the shape of each electronic component 20, and covers each electronic component 20 without a gap. Here, as with the heat radiating members 10b to 10d shown in FIGS. 1C to 1E, it is needless to say that the housing contact surface 103 and / or the substrate contact surface 101 may have a wider area. It is.

  Thus, according to the heat dissipation structure 1 of the first embodiment, the heat dissipation member 10 is provided between the first surface of the substrate 30 and the inner surface of the housing 40, and the heat dissipation member 10 is an electronic component. The heat radiating member 10 is sandwiched in the gap between the electronic component 20 and the housing 40 by covering all surfaces except the mounting surface 20 and closely contacting the first surface of the substrate 30 and the inner surface of the housing 40. Therefore, it is not necessary to newly provide a space for the heat radiating member 10. In addition, since the substrate contact surface 101 is in close contact with the first surface of the substrate 30 and the housing contact surface 103 is in close contact with the inner surface of the housing 40, heat generated from the electronic component 20 can be efficiently radiated.

(Second Embodiment)
Next, a heat dissipation structure according to the second embodiment will be described. FIG. 2 is a schematic view of a heat dissipation structure according to the second embodiment. 2A is a perspective view of a substrate on which electronic components are mounted and a heat dissipation member, and FIG. 2B is a cross-sectional view of a heat dissipation structure using the heat dissipation member shown in FIG. The heat dissipation structure 2 includes the housing 40, the substrate 30 disposed inside the housing 40, and the heat dissipation member 11 filled so as to fill a space between the first surface of the substrate 30 and the inner surface of the housing 40. With. The heat radiating member 11 includes a substrate contact surface 111, a recess 112, a housing contact surface 113, and a space filling unit 114.

  In FIG. 2, a plurality of electronic components 20 are mounted on the first surface of the substrate 30, and the heat dissipation member 11 has a plurality of recesses 112 corresponding to the shape of the electronic component 20. It is attached. Moreover, the number of electronic components 20 may be one or more.

  In the heat dissipation structure 2 according to the second embodiment, the heat dissipation member 11 fills the space between the first surface of the substrate 30 and the inner surface of the housing 40 as compared with the heat dissipation structure 1 according to the first embodiment. The difference is that the space filling portion 114 is filled.

  The heat radiating member 11 is molded according to the unevenness of the first surface of the substrate so as to fill a gap between the first surface of the substrate 30 and the inner surface of the housing 40, and the first surface of the substrate 30 and the housing 40. It is filled so as to fill the space between the inner surfaces.

  The substrate contact surface 111 is in close contact with the first surface of the substrate 30 and conducts heat of the electronic component 20 to the substrate 30. The recess 112 is provided in accordance with the shape of the electronic component 20 and covers all surfaces of the electronic component 20 except the board mounting surface without any gaps. The housing contact surface 113 is in close contact with the inner surface of the housing 40 and conducts heat of the electronic component 20 to the housing 40. The space filling unit 114 fills a space between the first surface of the substrate 30 and the inner surface of the housing 40, and conducts heat of the electronic component 20 to the substrate 30 and the housing 40. The heat conducted to the substrate 30 is conducted to the housing 40 through the heat radiating member 11.

  As shown in FIG. 2 (c), when the distance between the substrate 30 and the housing 40 is wide, the housing protrusion 41 is provided on the inner surface of the housing 40 facing the electronic component 20, thereby closely contacting the housing. Without increasing the thickness between the surface 113 and the recess 112, the housing contact surface 113 can be brought into close contact with the housing protrusion 41 and can be thermally conducted to the housing 40.

  As described above, according to the heat dissipation structure 2 of the second embodiment, the heat dissipation member 11 is filled so as to fill the space between the first surface of the substrate 30 and the inner surface of the housing 40. Since heat transmitted from the component 20 to the substrate 30 is also transmitted to the housing 40 via the heat radiating member 11, the heat is distributed and equalized, and the heat generated from the electronic component 20 is efficiently conducted to the housing 40. Heat can be dissipated in the entire housing 40.

  In the case where the heat radiating fins are provided on the outer surface of the housing 40, if the heat generation is locally large, the heat radiating fins need to be greatly lengthened. However, according to the heat radiating structure 2 of the second embodiment, Since heat can be dispersed, the length of the radiating fin can be optimized and the size of the radiating fin can be reduced.

  Furthermore, since the gap between the first surface of the substrate 30 and the inner surface of the housing 40 is filled with the heat radiating member 11, it is possible to prevent a short circuit due to dew condensation inside the housing 40, failure due to dust, etc., and improve waterproofness and dustproofness It becomes possible to do. In addition, since the heat dissipation member 11 is in close contact with the electronic component 20 and the substrate 30, it is possible to prevent the electronic component 20 from being shaken due to vibrations, damage due to the cable in the housing 40 coming into contact with the electronic component 20, and the like. It can be set as the structure excellent also in the property.

(Third embodiment)
Next, a heat dissipation structure according to the third embodiment will be described. FIG. 3 is a cross-sectional view of the heat dissipation structure according to the third embodiment. The heat dissipation structure 3 includes the housing 40, the substrate 30 disposed inside the housing 40, the electronic component 20 mounted on the first surface of the substrate 30, the inner surface of the housing 40, and the first of the substrate 30. A heat dissipation member 11 filled so as to fill a space between the two surfaces, an electronic component 21 mounted on a surface opposite to the first surface of the substrate 30 (hereinafter referred to as a second surface), and a substrate 30 and the heat dissipating member 12 disposed on the second surface. Since the heat radiating member 11 is the same as that of the second embodiment, the description thereof is omitted. The heat radiating member 12 has a substrate contact surface 121, a recess 122, and a space filling portion 123.

  Note that, as in the second embodiment, the number of electronic components 20 and electronic components 21 may be one or more. Similarly to the second embodiment, when the distance between the substrate 30 and the housing 40 is wide, the housing convex portion 41 may be provided on the inner surface of the housing 40 facing the electronic component 20.

  The heat dissipation structure 3 according to the third embodiment is different from the heat dissipation structure 2 according to the second embodiment in that the electronic component 21 and the heat dissipation member 12 are further provided.

  The substrate contact surface 121 is in close contact with the second surface of the substrate 30 and conducts heat of the electronic component 21 to the substrate 30. The recess 122 is provided in accordance with the shape of the electronic component 21 and covers all surfaces of the electronic component 21 except the board mounting surface without any gaps. The space filling unit 123 fills the space above the second surface of the substrate 30 and conducts the heat of the electronic component 21 to the substrate 30. The heat conducted to the substrate 30 is conducted to the housing 40 through the heat radiating member 11.

  Thus, according to the heat dissipation structure 3 of the third embodiment, the electronic component 21 is mounted on the second surface of the substrate 30 by bringing the heat dissipation member 12 into close contact with the second surface of the substrate 30. Even when the electronic component 21 is present, the heat generated from the electronic component 21 can be efficiently conducted to the housing 40 and radiated to the outside of the housing 40.

(Fourth embodiment)
Next, a heat dissipation structure according to the fourth embodiment will be described. FIG. 4 is a cross-sectional view of a heat dissipation structure according to the fourth embodiment. The heat dissipation structure 4 includes a housing 40, a substrate 30 disposed inside the housing 40, the electronic component 20 mounted on the first surface of the substrate 30, the first surface of the substrate 30, and the housing 40. The heat dissipating member 11 filled so as to fill the space between the inner surfaces, the electronic component 21 mounted on the second surface of the substrate 30, and the heat dissipating member 12 disposed on the second surface of the substrate 30. And a heat radiating plate (for example, an aluminum plate) 50 disposed on the heat radiating member 12. Since the heat radiating member 11 is the same as that of 2nd and 3rd embodiment, description is abbreviate | omitted. The heat dissipating member 12 has a substrate contact surface 121, a recess 122, a space filling portion 123, and a heat sink contact surface 124.

  Note that, as in the second and third embodiments, the number of electronic components 20 and electronic components 21 may be one or more. Similarly to the second and third embodiments, when the distance between the substrate 30 and the housing 40 is wide, the housing protrusion 41 may be provided on the inner surface of the housing 40 facing the electronic component 20. Good.

  The heat dissipating structure 4 according to the fourth embodiment is different from the heat dissipating structure 3 according to the third embodiment in that the heat dissipating member 12 has a heat dissipating plate contact surface 124 and further includes a heat dissipating plate 50. .

  The substrate contact surface 121 is in close contact with the second surface of the substrate 30 and conducts heat of the electronic component 21 to the substrate 30. The recess 122 is provided in accordance with the shape of the electronic component 21 and covers all surfaces of the electronic component 21 except the board mounting surface without any gaps. The space filling unit 123 fills a space between the heat sink 50 and the second surface of the substrate 30 and conducts heat of the electronic component 21 and the substrate 30 to the housing 40. The heat sink contact surface 124 is in close contact with the heat sink 50 and conducts heat of the electronic component 21 to the heat sink 50.

  The heat radiating plate 50 is disposed in close contact with the heat radiating member 12. Further, the heat radiating plate 50 is joined to the housing 40 and conducts heat of the electronic component 21 conducted through the heat radiating member 12 to the housing 40.

  In addition, when the space | interval of the heat sink 50 and the board | substrate 30 is wide, by providing the heat sink convex part (not shown) in the inner surface of the heat sink 50 which opposes the electronic component 21, the heat sink contact surface 124 and a recessed part are provided. The heat radiation plate contact surface 124 can be brought into close contact with the heat radiation plate protrusion without increasing the thickness between the heat dissipation plate 122 and the heat sink.

  As described above, according to the heat dissipation structure 4 of the fourth embodiment, the heat dissipation plate 12 includes the heat dissipation plate 50 disposed in close contact with the heat dissipation member 12 and joined to the housing 40. Since the space between the second surfaces of the substrate 30 is filled to fill the space, the heat generated from the electronic components 21 is radiated from the heat sink even when the electronic component 21 is mounted on the second surface of the substrate 30. It is possible to conduct the heat to the housing 40 more efficiently through the heat sink 50 and to dissipate heat to the outside of the housing 40.

  Each of the above embodiments has been described as a representative example, but it will be apparent to those skilled in the art that many changes and substitutions can be made within the spirit and scope of the invention. Therefore, the present invention should not be construed as being limited by the above-described embodiments, and various modifications and changes can be made without departing from the scope of the claims. For example, in the fourth embodiment, as shown in FIG. 5, the heat dissipation member 12 may not have the space filling portion 123 and may have a heat dissipation structure 4 having a gap between adjacent electronic components 21. Even with such a heat dissipation structure, a predetermined heat dissipation effect can be obtained.

1, 2, 3, 4 Heat dissipation structure 10, 11, 12 Heat dissipation member 20, 21 Electronic component 30 Substrate 40 Case 41 Case convex portion 50 Heat sink 101, 111, 121 Substrate contact surface 102, 112, 122 Concavity 103, 113 Housing close contact surface 114, 123 Space filling portion 124 Heat sink close contact surface

Claims (6)

A heat dissipation structure that dissipates heat generated from electronic components inside the housing,
A substrate disposed within the housing and having a first surface facing the inner surface of the housing;
An electronic component mounted on the first surface of the substrate;
A heat dissipating member that is closely attached between the first surface of the substrate and the inner surface of the housing,
The heat dissipation member covers all surfaces except a mounting surface of the electronic component, and is in close contact with the first surface of the substrate and the inner surface of the housing.   The heat dissipation structure according to claim 1, wherein the heat dissipation member is filled so as to fill a space between the first surface of the substrate and the inner surface of the housing. An electronic component mounted on a second surface opposite to the first surface of the substrate;
A second heat dissipating member disposed on the second surface of the substrate,
The second heat radiating member covers all surfaces except the mounting surface of the electronic component mounted on the second surface of the substrate, and is in close contact with the second surface of the substrate, The heat dissipation structure according to claim 1 or 2.   The heat dissipation structure according to claim 3, further comprising a heat dissipation plate disposed in close contact with the second heat dissipation member and joined to the housing.   The heat dissipation structure according to claim 4, wherein the second heat dissipation member is filled to fill a space between the heat dissipation plate and the second surface of the substrate. A heat dissipation member that is closely attached between a substrate on which an electronic component is mounted on one surface, and an inner surface of a housing having the substrate inside, and dissipates heat generated from the electronic component,
A recess that covers all surfaces except the mounting surface of the electronic component;
A substrate contact surface in close contact with one surface of the substrate;
A housing contact surface closely contacting the inner surface of the housing;
It has heat dissipation member characterized by having.

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