JP2013077604A - Electronic component unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component unit, capable of efficiently radiating heat generated from an electronic component without affecting the electronic component.SOLUTION: In an electronic component unit 10A in which a pyrogenic electronic component 14 mounted on one surface side of a substrate 12 is housed in a box-shaped case 16, the electronic component 14 is housed in the case 16 in such a manner that the top end face 14a of the electronic component 14 faces the bottom face (bottom face 20a of a partition portion 20) of the case 16 with a predetermined gap t1 between with the bottom face 20a. On the bottom face 20a side of the case 16, there is provided a bottom face side heat dissipation member (heat dissipation resin layer 24) capable of filling the gap t1 with a thickness capable of forming a space portion 28 between with the substrate 12. At least a portion of the side face 14b of the electronic component 14 faces the space portion 28.

Description

  The present invention relates to an electronic component unit in which an electronic component mounted on a substrate is accommodated in a box-shaped case.

  In an electric appliance or the like, an electronic component unit in which an electronic component mounted on a substrate is accommodated in a box-shaped case is incorporated. When an electric current is supplied to an electronic component housed in such an electronic component unit and operated, heat is generated from the electronic component. When this heat is stored in the case, the performance as an electronic component unit cannot be satisfied. For this reason, it is necessary to efficiently dissipate the heat generated from the electronic component. Various electronic component units that can efficiently dissipate heat generated from electronic components have been proposed (see, for example, Patent Document 1).

  FIG. 6 is a diagram for explaining the electronic component unit 900 disclosed in Patent Document 1. In FIG. As shown in FIG. 6, an electronic component unit 900 disclosed in Patent Document 1 (referred to as a conventional electronic component unit 900) has a heat-generating electronic component 920 mounted on one side of a substrate 910 made of metal. The case 930 is accommodated in a box-shaped case 930, and the case 930 is filled with a heat radiating resin 940 as a heat radiating member. For this reason, each electronic component 920 will be in the state covered with the heat-radiating resin 940 over the perimeter.

JP 2005-294703 A

  According to the conventional electronic component unit 900, the heat generated from each electronic component 920 is efficiently transferred to the case 930 through the heat radiating resin 940. For this reason, it is difficult for heat to be stored in the case 930, and the temperature of the electronic component 920 can be prevented from becoming abnormally high.

  However, in the conventional electronic component unit 900, each electronic component 920 is covered with the heat-dissipating resin 940 over the entire circumference. For this reason, in the case of an electronic component with a large amount of heat generation, the degree of expansion / contraction of the heat-dissipating resin is large, and if the heat-dissipating resin 940 repeatedly expands / contracts, the electronic component may be adversely affected. In particular, when the electronic component is a choke coil, the core portion of the choke coil is generally made of a brittle material. Therefore, if the entire choke coil is covered with resin, the heat-dissipating resin 940 repeatedly expands and contracts. As a result, there may be a problem that the core portion is damaged. Such a defect may occur not only in the choke coil but also in electronic components using a material that is easily affected by expansion / contraction of the heat-dissipating resin 940.

  Accordingly, an object of the present invention is to provide an electronic component unit that can efficiently dissipate heat generated from the electronic component without adversely affecting the electronic component.

  [1] An electronic component unit of the present invention is an electronic component unit in which a heat-generating electronic component mounted on one surface side of a substrate is accommodated in a box-shaped case, and the electronic component is a tip of the electronic component. The surface faces the bottom surface of the case and is accommodated in the case so as to have a predetermined gap between the bottom surface, the bottom surface side of the case can be filled with the gap, and A bottom surface side heat radiating member having a thickness capable of forming a space portion between the substrate and the substrate is provided, and at least a part of a side surface of the electronic component faces the space portion.

  [2] In the electronic component unit of the present invention, it is preferable that the bottom surface side heat radiating member has a thickness such that a front end surface of the electronic component is embedded in the bottom surface side heat radiating member.

  [3] In the electronic component unit of the present invention, it is also preferable that the bottom surface side heat radiating member has a thickness such that the front end surface of the electronic component is in pressure contact with the surface of the bottom surface side heat radiating member.

  [4] In the electronic component unit of the present invention, it is also preferable that the bottom surface side heat radiating member has a thickness such that the tip surface of the electronic component is in contact with the surface of the bottom surface side heat radiating member.

  [5] In the electronic component unit of the present invention, a protruding wall is provided on the bottom surface of the case so as to surround the outer peripheral edge of the tip surface of the electronic component over the entire circumference, and in the space surrounded by the protruding wall. It is preferable that the bottom surface side heat radiating member is provided.

  [6] In the electronic component unit of the present invention, it is preferable that the bottom surface side heat radiating member is a heat radiating resin.

  [7] In the electronic component unit of the present invention, it is preferable that a lid-side heat radiating member is provided between the other surface side of the substrate and the lid plate of the case.

  [8] In the electronic component unit of the present invention, the electronic component is preferably an electronic component for power supply.

  [9] In the electronic component unit of the present invention, the electronic component is preferably a choke coil.

  [10] In the electronic component unit of the present invention, the case is preferably an aluminum case.

  According to the electronic component unit of the present invention, since the entire periphery of the electronic component is not covered with the heat radiating member, an adverse effect such as “the heat radiating member repeatedly expands / contracts and damages the core portion”. Will not affect the electronic parts. Moreover, since the heat generated by the electronic component can be radiated to the case via the bottom surface side heat dissipation member with which the tip surface of the electronic component is in contact, the heat generated by the electronic component can be efficiently radiated. it can.

  In addition, since the entire periphery of the electronic component is not covered with the heat radiating member, the amount of the heat radiating member can be reduced, so that an effect of reducing the weight of the electronic component unit can be obtained.

It is a disassembled perspective view shown in order to demonstrate 10 A of electronic component units which concern on Embodiment 1. FIG. It is an expanded partial sectional view which shows the contact state of the front end surface 14a of the electronic component 14 in the electronic component unit 10A which concerns on Embodiment 1, and a thermal radiation member. It is an expanded partial sectional view which shows the contact state of the front end surface 14a of the electronic component 14 in the electronic component unit 10B which concerns on Embodiment 2, and a thermal radiation member. It is an expanded partial sectional view which shows the contact state of the front end surface 14a of the electronic component 14 in the electronic component unit 10C which concerns on Embodiment 3, and a thermal radiation member. It is an expanded partial sectional view which shows the contact state of the front end surface 14a of the electronic component 14 in the electronic component unit 10D which concerns on Embodiment 4, and a thermal radiation member. It is a figure shown in order to demonstrate the electronic component unit 900 currently disclosed by patent document 1. FIG.

  Hereinafter, embodiments of the present invention will be described.

[Embodiment 1]
FIG. 1 is an exploded perspective view for explaining an electronic component unit 10A according to the first embodiment. FIG. 2 is an enlarged partial cross-sectional view illustrating a contact state between the front end surface 14a of the electronic component 14 and the heat dissipation member in the electronic component unit 10A according to the first embodiment.

  As shown in FIG. 1, the electronic component unit 10A according to the first embodiment includes a plurality of heat-generating electronic components 14 (in a partition portion 20 formed by partitioning a box-shaped case 16 with partition plates 18 and 18. Hereinafter, the electronic component 14 may be simply stored). The electronic component 14 is accommodated such that the rear end surface is mounted on one surface side of the substrate 12 and the front end surface 14a is on the bottom surface 20a of the partition portion 20 (also referred to as the bottom surface of the case 16). At this time, a predetermined gap t <b> 1 is provided between the bottom surface 20 a of the partition part 20 and the tip surface 14 a of the electronic component 14.

  The height h1 of the partition plates 18 and 18 (height h1 from the bottom surface of the case 16 to the upper end of the partition plates 18 and 18) is the height h2 of the side plate of the case 16 (from the bottom surface of the case 16 to the upper end of the side plate). The height h2) is lower. For this reason, when the electronic component 14 attached to the substrate 12 is accommodated in a state facing the bottom surface 20 a side of the partition portion 20, the substrate 12 is accommodated in the case 16 without protruding above the case 16.

  The opening surface of the case 16 in which the electronic component 14 is accommodated together with the substrate 12 is closed by the lid plate 22. The case 16, the partition plate 18 and the cover plate 22 are made of aluminum. Thus, by making the case 16, the partition plate 18, and the lid plate 22 from aluminum, the heat dissipation of the heat generated from the electronic component 14 can be further improved.

  In the electronic component unit 10A according to the first embodiment, the electronic component 14 is assumed to be an electronic component for power supply. Note that examples of the power supply electronic component include a power transistor, a transformer, a choke coil, and the like. Here, a choke coil is assumed.

  Further, a bottom surface side heat radiating member 24 is provided between the bottom surface 20a of the partition portion 20 and the front end surface 14a of the electronic component 14 so as to fill the gap t1. In the electronic component unit 10A according to the first embodiment, the bottom surface side heat radiating member 24 is a heat radiating resin, and a heat radiating resin layer is formed by the heat radiating resin. Hereinafter, the bottom surface side heat radiating member 24 may be referred to as a heat radiating resin layer 24. The heat-dissipating resin layer 24 has a thickness t2 such that when the electronic component 14 is accommodated, the front end surface 14a of the electronic component 14 is embedded in the heat-dissipating resin layer 24 by a slight depth. . For this reason, a space 28 is formed between the surface of the heat-dissipating resin layer 24 and the substrate 12.

  The depth at which the front end surface 14a of the electronic component 14 is embedded in the heat-dissipating resin layer 24 (referred to as an embedded depth) can be set as appropriate depending on the type of the electronic component 14 and the amount of heat generated. It is preferable to obtain the optimum embedment depth by analysis or experiment according to the type or the calorific value.

  The heat-dissipating resin layer 24 can be formed by, for example, injecting and curing filler-containing resin after housing the electronic component 14 in the case 16.

  The electronic component unit 10A according to the first embodiment is configured as described above. For this reason, the electronic component 14 is in a state in which at least a part of the side surface 14 b faces the space portion 28 formed in the case 16. In the electronic component unit 10 </ b> A according to the first embodiment, the tip surface 14 a of the electronic component 14 is embedded in the heat-dissipating resin layer 24 to a slight depth, and therefore the side surface 14 b of the electronic component is almost the same. Is in a state facing the space 28.

  Thus, in the electronic component unit 10A according to the first embodiment, the entire circumference of the electronic component 14 is not covered with the heat-dissipating resin. For this reason, according to the electronic component unit 10A according to the first embodiment, it is possible to prevent an adverse effect on the electronic component due to repeated expansion and contraction of the heat-dissipating resin. In particular, in the electronic component unit 10A according to the first embodiment, since the electronic component 14 is a choke coil, the heat radiation resin repeatedly expands and contracts to prevent the core portion from being damaged. be able to.

  In addition, since the heat generated by the electronic component 14 can be radiated from the front end surface 14a of the electronic component 14 to the case through the bottom surface side heat radiating member 24, the heat generated by the electronic component 14 can be efficiently radiated. Can do.

  Further, since the entire periphery of the electronic component 14 is not covered with the heat-dissipating resin, the amount of heat-dissipating resin to be used can be reduced, and the electronic component unit 10A can be reduced in weight.

  Further, in the electronic component unit 10 </ b> A according to the first embodiment, as shown in FIG. 2, a lid-side heat dissipation member 26 is provided between the other surface side of the substrate 12 (upper surface side in FIG. 2) and the lid plate 22. Is provided. The lid-side heat dissipation member 26 is preferably provided between the other surface side of the substrate 12 and the lid plate 22 and at a location corresponding to the electronic component 14. With such a configuration, the heat generated in the electronic component 14 can be efficiently radiated to the lid plate 22 via the substrate 12 and the lid-side heat radiating member 26. As the lid-side heat radiation member 26, silicon rubber can be preferably used.

[Embodiment 2]
FIG. 3 is an enlarged partial cross-sectional view illustrating a contact state between the front end surface 14a of the electronic component 14 and the heat dissipation member in the electronic component unit 10B according to the second embodiment. 3 corresponds to FIG. 2. In FIG. 3, the same members as those in FIG. 2 are denoted by the same reference numerals.

  As shown in FIG. 3, the electronic component unit 10 </ b> B according to the second embodiment is in a state in which the tip surface 14 a of the electronic component 14 is in pressure contact with the surface of the heat-dissipating resin layer 24. Even with this configuration, as with the electronic component unit 10A according to the first embodiment, the entire circumference of the electronic component 14 is not covered with the heat-dissipating resin, and thus the electronic component unit 10A according to the first embodiment Similar effects can be obtained.

  In the electronic component unit 10 </ b> B according to the second embodiment, the heat radiating resin layer 24 can be formed in advance on the bottom surface 20 a side of the partition portion 20 of the case 16. Note that the thickness t3 of the heat-dissipating resin layer 24 at this time can fill the gap t1 between the front end surface 14a of the electronic component 14 and the bottom surface 20a of the partition portion 20, and the front end surface 14a of the electronic component 14 However, it is preferable that the thickness of the heat dissipation resin layer 24 be in a pressure contact state.

  Thus, according to the electronic component unit 10 </ b> B according to the second embodiment, the thickness t <b> 3 of the heat radiating resin layer 24 is set to such a thickness that the front end surface 14 a of the electronic component 14 is in pressure contact with the surface of the heat radiating resin layer 24. Therefore, the heat radiating resin layer 24 can be formed in advance on the bottom surface 20 a side of the partition portion 20 of the case 16. Thereby, the manufacturing process of the electronic component unit 10B can be simplified. In addition, before the actual heat-dissipating resin is poured, a silicon rubber having a thermal conductivity equivalent to that of the heat-dissipating resin and having a thickness equivalent to the thickness t3 of the heat-dissipating resin layer 24 is laid. Thus, it is possible to easily conduct an experiment for examining the heat dissipation of heat generated from electronic components. If a favorable result is obtained as a result of such an experiment, the electronic component unit 10B can be efficiently manufactured if the heat-dissipating resin is actually poured until the thickness t3 is reached.

  Further, in the electronic component unit 10B according to the second embodiment, a heat radiating sheet (not shown) can be used. In this case, the electronic component unit 10B has a thickness equivalent to the thickness t3 of the heat radiating resin layer 24, and A heat radiating sheet having a thermal conductivity equivalent to that of the heat radiating resin layer 24 may be laid in advance.

[Embodiment 3]
FIG. 4 is an enlarged partial cross-sectional view showing a contact state between the front end surface 14a of the heat-generating electronic component 14 and the heat dissipation member in the electronic component unit 10C according to the third embodiment. 4 corresponds to FIG. 3. In FIG. 4, the same members as those in FIG. 3 are denoted by the same reference numerals.

  As shown in FIG. 4, the electronic component unit 10 </ b> C according to the third embodiment is in a state in which the tip surface 14 a of the electronic component 14 is in contact with the surface of the heat-dissipating resin layer 24. Note that the thickness t4 of the heat-dissipating resin layer 24 in the electronic component unit 10C according to the third embodiment is only required to allow the tip surface 14a of the electronic component 14 to be in contact with the surface of the heat-dissipating resin layer 24. It may be equivalent to the gap t1 between the front end surface 14a and the bottom surface 20a of the partition portion 20.

  Even with this configuration, as with the electronic component unit 10A according to the first embodiment, the entire circumference of the electronic component 14 is not covered with the heat-dissipating resin, and thus the electronic component unit 10A according to the first embodiment Similar effects can be obtained.

  In the electronic component unit 10 </ b> C according to the third embodiment, the thickness t <b> 4 of the heat radiating resin layer 24 is set to such a thickness that the tip surface 14 a of the electronic component 14 is in pressure contact with the surface of the heat radiating resin layer 24. Similar to the electronic component unit 10 </ b> B according to the second embodiment, the heat radiating resin layer 24 can be formed in advance on the bottom surface 20 a side of the partition portion 20 of the case 16. Thereby, the manufacturing process of the electronic component unit 10C can be simplified. In addition, before the actual heat-dissipating resin is poured, a silicon rubber having a thermal conductivity equivalent to that of the heat-dissipating resin and having a thickness equivalent to the thickness t4 of the heat-dissipating resin layer 24 is laid. Thus, it is possible to easily conduct an experiment for examining the heat dissipation of heat generated from electronic components. If a favorable result is obtained as a result of such an experiment, the electronic component unit 10C can be efficiently manufactured if the heat-dissipating resin is actually poured into the thickness t4.

  In addition, in the electronic component unit 10C according to the third embodiment, a heat dissipation sheet (not shown) can be used as in the electronic component unit 10B according to the second embodiment.

[Embodiment 4]
FIG. 5 is an enlarged partial cross-sectional view showing a contact state between the distal end surface 14a of the heat-generating electronic component 14 and the heat dissipation member in the electronic component unit 10D according to the fourth embodiment. 5 corresponds to FIG. 2. In FIG. 4, the same members as those in FIG. 2 are denoted by the same reference numerals.

  As shown in FIG. 5, the electronic component unit 10 </ b> D according to the fourth embodiment includes a protruding wall 30 on the bottom surface of the case 16 (the bottom surface 20 a on the partition 20 side). The annular projecting wall 30 is provided so as to surround the outer peripheral edge of the front end surface 14a of the electronic component 14 over the entire circumference. The space surrounded by the annular projecting wall 30 is previously filled with a heat-dissipating resin by a predetermined thickness (the thickness is t2 as in FIG. 2).

  With this configuration, when the electronic component 14 is accommodated so that the front end surface 14a of the electronic component 14 is inserted into the space surrounded by the annular projecting wall 30, the front end surface 14a of the electronic component 14 has a heat dissipation property. The resin layer 24 is embedded. Since this state is the same as that of the electronic component unit 10A according to the first embodiment, the same effect as that of the electronic component unit 10A according to the first embodiment can be obtained. Further, only in the portion corresponding to the front end surface of the electronic component 14 Since the heat radiating resin layer 24 is formed, the amount of heat radiating resin to be used can be reduced.

  Further, the front end surface 14a of the electronic component 14 is not embedded in the heat-dissipating resin layer 24, but the front-end surface 14a of the electronic component 14 is used as the heat-dissipating resin layer as in the electronic component unit 10B according to the second embodiment. The front surface 14a of the electronic component 14 may be brought into contact with the surface of the heat-dissipating resin layer 24 as in the electronic component unit 10C according to the third embodiment. In this case, a heat dissipation sheet can be used.

  5 illustrates the case where the inner diameter of the annular projecting wall 30 is slightly larger than the outer diameter of the electronic component 14. However, the inner diameter and height of the annular projecting wall 30 are appropriately determined depending on the type of the component. An appropriate size can be provided. Further, depending on the type of electronic component, it does not necessarily have to be annular.

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the following modifications are possible.

  (1) In each of the above embodiments, the case where the heat radiating resin is used as the bottom surface side heat radiating member 24 is exemplified. However, if the member is excellent in heat radiating property and electrical insulation, other members should be used. Is also possible. Further, the case where silicon rubber or the like is used as the lid-side heat radiating member 26 is exemplified, but other members can be used as long as they are members having excellent heat dissipation and electrical insulation. Moreover, if the heat radiation amount from the front end surface of the electronic component 14 is sufficient, the lid-side heat radiation member 26 may not be provided.

  (2) In each of the above embodiments, in order to further increase the heat dissipation amount of the electronic component 14, for example, a fan may be installed outside the case 16, and an air flow may be generated in the case 16.

  10A, 10B, 10C, 10D ... electronic component unit, 12 ... substrate, 14 ... electronic component, 14a ... tip surface of electronic component, 14b ... side surface of electronic component, 16 ... Case, 18 ... partition plate, 20 ... partition portion, 20a ... bottom surface of partition portion, 22 ... lid plate, 24 ... heat radiating resin layer (bottom surface side heat radiating member), 26 ... Cover side heat radiating member, 28 ... space, 30 ... protruding wall, h1 ... height of partition plate 18, h2 ... height of side plate, t1 ... gap, t2, t3 t4: thickness of the heat-dissipating resin layer 24

Claims (10)

An electronic component unit containing a heat-generating electronic component mounted on one side of a substrate in a box-shaped case,
The electronic component is housed in the case so that the front end surface of the electronic component faces the bottom surface of the case and has a predetermined gap between the bottom surface and the electronic component,
The bottom surface side of the case is provided with a bottom surface side heat dissipation member having a thickness capable of filling the gap and forming a space with the substrate, and at least a side surface of the electronic component. A part of the electronic component unit faces the space. The electronic component unit according to claim 1,
The electronic component unit according to claim 1, wherein the bottom surface side heat radiating member has a thickness such that a front end surface of the electronic component is embedded in the bottom surface side heat radiating member. The electronic component unit according to claim 1,
The electronic component unit, wherein the bottom surface side heat radiation member has a thickness such that a tip surface of the electronic component is in pressure contact with a surface of the bottom surface heat radiation member. The electronic component unit according to claim 1,
The electronic component unit, wherein the bottom surface heat dissipation member has a thickness such that a front end surface of the electronic component is in contact with a surface of the bottom surface heat dissipation member. In the electronic component unit according to any one of claims 1 to 4,
A protruding wall that surrounds the outer peripheral edge of the tip surface of the electronic component over the entire circumference is provided on the bottom surface of the case, and the bottom surface side heat dissipation member is provided in a space surrounded by the protruding wall. A featured electronic component unit. In the electronic component unit according to any one of claims 1 to 5,
The electronic component unit, wherein the bottom surface side heat radiating member is a heat radiating resin. In the electronic component unit according to any one of claims 1 to 6,
An electronic component unit, wherein a lid-side heat radiating member is provided between the other surface side of the substrate and the lid plate of the case. In the electronic component unit according to any one of claims 1 to 7,
The electronic component unit is an electronic component for a power source. The electronic component unit according to claim 8,
The electronic component unit is a choke coil. In the electronic component unit according to any one of claims 1 to 9,
The electronic component unit, wherein the case is an aluminum case.

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