JP2005223029A - Electronic device case - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To thin an electronic device case, from which heat is dissipated by means of natural convection. <P>SOLUTION: In the electronic device case, a plurality of components (11, 18), for which a heat dissipating measure should be taken, are housed in separate chambers (27, 28), respectively, and respective chambers (27, 28) are lined up vertically. The vertically lined up chambers (27, 28) do not result in the expansion of the size of the cross section of the case, thus leading to the miniaturization (thinning) of the case. In addition, by making respective natural heat dissipating paths (24, 25) in the chambers (27, 28) independent of each other, for example, the effect of heat from the lower room (28) is prevented from coming up to the upper chamber (27). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electronic device casing, and more particularly, to a heat dissipation technique inside the casing, in particular, a heat dissipation technique using natural convection.

In general, the release (heat dissipation) of heat trapped inside an electronic device casing is (1) forced ventilation using a fan, (2) natural heat dissipation using a heat sink,
(3) It is carried out by any one of natural heat radiation or a combination thereof left to air convection.

  Although (1) is the most desirable in terms of heat dissipation effect, since a fan and a drive source (motor) are required, there are inconveniences such as an increase in the size of the housing, power saving and quietness. On the other hand, (2) and (3) have advantages in terms of power saving and quietness, but (2) requires a heat sink having a size corresponding to the heat capacity. It is inevitable to enlarge the case. Therefore, in the case of an electronic device casing that requires low power, low noise, and downsizing, the technology (3), that is, the natural heat dissipation that is left to air convection is employed.

  As a conventional technique related to the above (3), for example, as described in Patent Document 1, a main heat generation source (generally a power supply unit) is positioned at the uppermost part of the casing. According to this, since the power supply unit is located at the top of the casing, in other words, the electronic units other than the power supply unit are located under the power supply unit, the electronic unit is heated at a high temperature heated by the power supply unit. Not exposed to air. Therefore, there is an advantage that the operation temperature of the electronic unit can be suppressed and deterioration of electronic components constituting the electronic unit can be prevented, and further, downsizing of the housing, power saving and quietness can be achieved. .

Japanese Utility Model Publication No. 6-86377

  By the way, some electronic units housed in a housing generate considerable heat if not as much as a power supply unit. Further, even if a large number of electronic units that generate relatively little heat are stored, the total amount of heat becomes considerably large.

  When such an electronic unit (a heat generation source similar to the power supply unit) is accommodated in the housing together with the power supply unit, according to the above-described conventional technique (3), the “unit” However, if these two heat sources (power supply unit and electronic unit) are positioned at the top of the casing, the lateral cross-sectional size of the casing must be increased. It means you have to.

  In other words, when an electronic unit that generates little heat is housed in a casing together with a power supply unit, the power supply unit should be positioned at the top and the electronic unit positioned below it. , So that it does not increase the cross-sectional size of the housing in the lateral direction. However, when storing a heat-generating electronic unit together with the power supply unit, the electronic unit may be placed under the power supply unit. This is because it is necessary to “position both of them at the top” in accordance with the above-mentioned concept, and eventually it must be arranged in the “lateral direction”. Therefore, there is a drawback that the lateral cross-sectional size of the casing is increased (enlargement of the casing) by the lateral arrangement space.

  Accordingly, an object of the present invention is to provide a technique that contributes to a reduction in the thickness of an electronic device casing that performs heat dissipation by natural convection.

The electronic device casing according to the present invention accommodates a plurality of components that require heat dissipation measures in individual chambers, and arranges the chambers in the vertical direction, and provides a natural heat dissipation path for each chamber. It is characterized by having become independent.
Moreover, the preferable aspect is characterized in that each of the chambers is partitioned between adjacent chambers by an air shielding plate,
Alternatively, each of the chambers is characterized in that adjacent chambers are partitioned by an air shielding plate, and a material having an electromagnetic shielding effect is used for the air shielding plate,
Alternatively, the natural heat dissipation path is formed by a large number of air holes drilled in the case of the housing,
Alternatively, the natural heat dissipation path is formed by a large number of air holes formed in a case of the housing and openings formed in the case.

According to the present invention, a plurality of components that require heat dissipation measures are housed in individual chambers, and those chambers are arranged in the vertical direction, so that the lateral cross-sectional size of the housing is not increased, Therefore, the housing can be downsized (particularly thinned). Moreover, since the natural heat radiation path of each chamber is made independent, for example, the influence of the heat of the lower chamber does not reach the upper chamber.
In addition, according to a preferred aspect, each of the chambers is partitioned between adjacent chambers by an air shielding plate, so that the above-described effects (miniaturization of the casing and thermal influence between the chambers) can be achieved with a simple structure. Elimination).
According to another preferred embodiment, each of the chambers is partitioned between adjacent chambers by an air shielding plate, and the air shielding plate is made of a material having an electromagnetic shielding effect. A mutual electromagnetic shielding effect is also obtained.
According to another preferred embodiment, the natural heat dissipation path is formed by a large number of air holes drilled in the case of the housing, so that heat of each chamber can be released by air convection for each chamber. it can.
According to another preferred embodiment, the natural heat dissipation path is formed by a large number of air holes drilled in a case of the housing and openings formed in the case, and therefore, the natural heat dissipation path, particularly through the openings. In the heat dissipation path, the air resistance can be reduced to improve the heat dissipation efficiency.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, taking as an example application to a signal level adjusting apparatus for a television common hearing system. It should be noted that the specific details or examples in the following description and the illustrations of numerical values, character strings, and other symbols are only for reference in order to clarify the idea of the present invention, and the present invention may be used in whole or in part. Obviously, the idea of the invention is not limited. In addition, a well-known technique, a well-known procedure, a well-known architecture, a well-known circuit configuration, and the like (hereinafter, “well-known matter”) are not described in detail, but this is also to simplify the description. Not all or part of the matter is intentionally excluded. Such well-known matters are known to those skilled in the art at the time of filing of the present invention, and are naturally included in the following description.

  By the way, the signal level adjustment device for the common listening system is a head end device that performs waveform shaping and level adjustment on the received signal of each channel of terrestrial digital broadcasting, and supplies the adjusted signal to the joint reception facility That is. More specifically, in conventional terrestrial analog broadcasting, broadcasting is performed on at least every other channel, but in terrestrial digital broadcasting, each channel is an OFDM (orthogonal frequency multiplexed) signal, and terrestrial analog broadcasting Unlike in many cases, it is broadcast on adjacent channels. For this reason, in the reception in the actual field, the level deviation between the reception channels is likely to occur. In particular, when the level deviation is large, there is a possibility that nonlinear distortion may occur in the amplification unit of the television receiver. For the purpose of eliminating (non-linear distortion), the above device (signal level adjusting device for a hearing system) is used.

  FIG. 1 and FIG. 2 are an external view and an internal structure diagram of a signal level adjusting device for a common hearing system. In this figure, a signal level adjusting device for a hearing system is housed in a wall-mounted housing 1 (electronic device housing), which is formed by bending or welding a metal plate. A box-shaped case 2 having one open surface, and a back plate 3 that closes the open surface of the case 2 and is attached to a wall surface (not shown) or the like.

  In each surface (upper surface, left and right side surfaces, lower surface and front surface) other than the open surface of the case 2, a large number of air holes 4 to 10 having a small area are formed. In the figure, since the right side surface and the lower surface of the case 2 are shaded, the air holes drilled in those surfaces are not visible. However, for convenience of explanation, these air holes are denoted by reference numerals (8 to 8). It will be expressed only by 10).

  That is, the air hole 4 is drilled in the upper surface of the case 2 (shown), the air hole 5 is drilled in the upper front part of the case 2 (shown), the air hole 6 is drilled in the upper part of the left side surface of the case 2 (shown), and the air hole 7 is drilled in the lower part of the left side surface of the case 2 (shown). The air hole 8 is drilled in the upper part of the right side surface of the case 2 (not shown), the air hole 9 is drilled in the lower part of the right side surface of the case 2 (not shown), The air hole 10 is formed in the lower surface of the case 2 (not shown).

  Incidentally, the size of these air holes 4 to 10 (including the number of holes) should be set appropriately in consideration of both the EMI (unwanted electromagnetic wave) suppression effect and the air heat dissipation effect. is there. That is, although the large air holes 4 to 10 are beneficial in terms of heat dissipation effect, they are not preferable in terms of EMI countermeasures. Conversely, the smaller air holes 4 to 10 are beneficial in terms of EMI countermeasures, Since the heat dissipation effect is not preferable, the actual size of the air holes 4 to 10 is set to an optimum value by calculation or experiment in consideration of both the EMI frequency inside the housing 1 and the air resistance. do it.

  A rectangular marking representing the position of each of n (for example, 10) level converter units 11 (components serving as heat generation sources) housed in the case 2 is provided on the front surface of the case 2. Lines 12 are drawn, and access holes 13 for adjusting the levels of the level converter units 11 are formed. In addition, although not shown, transmitted light such as a power indicator lamp and an operation status indicator lamp is transmitted. Windows are in place.

  The back plate 3 has bolt fixing holes 14 to 17 drilled at arbitrary positions (in the illustrated example, each corner portion) of the peripheral portion of the back plate 3, and a power source near the top of the back plate 3. The unit 18 (component which becomes a heat generation source) is attached, and ten level converter units 11 arranged side by side on the two electronic boards 19 and 20 attached to the lower side of the power supply unit 18. Is attached. The level converter unit 11 is for individually adjusting the signal level for each reception channel in a television common listening system (particularly for digital terrestrial broadcasting). Level adjustment elements 21 and 22 that are accessible from the front.

  Here, when comparing two terrestrial digital broadcasts and digital terrestrial broadcasts, the carrier density of the former (digital terrestrial broadcast) is higher than that of the latter (terrestrial analog broadcast). The power consumption of the level converter unit 11 used for digital broadcasting is large. This means that the calorific value of the level converter unit 11 used for terrestrial digital broadcasting is large, and when all of the n (n = 10) level converter units 11 are used for terrestrial digital broadcasting, A simple calculation suggests that it generates n times as much heat.

  On the other hand, since the power supply unit 18 is also a component that serves as a heat generation source, the illustrated housing 1 houses these two types of heat generation sources (the power supply unit 18 and the n level converter units 11). become. As can be understood from the drawing, the power supply unit 18 is located at the uppermost part of the casing 1 and the n level converter units 11 are located below the power supply unit 18. That is, the power supply unit 18 and the level converter unit 11 are arranged in the “vertical direction”. When arranged in the vertical direction in this way, as described at the beginning, the lateral cross-sectional size of the housing 1 can be reduced, which contributes to the thinning of the housing 1. On the other hand, n Since the air heated by the level converter unit 11 rises, there is a drawback that heat dissipation of the power supply unit 18 is hindered.

  Therefore, in the present embodiment, in order to eliminate the above-described drawbacks, a material having an electromagnetic shielding effect (for example, a metal material) is preferably formed between the power supply unit 18 and the n level converter units 11. The air shielding plate 23 is arranged.

  The air shield plate 23 has one end fixed to the back plate 3 and the other end abutted against the inner surface of the case 2 (or a minute gap may be provided between the case 2) and the side thereof. The length in the direction is made to substantially match the size of the case 2 in the lateral direction, and the cross section is bent into a "<" shape.

  FIG. 3 is a diagram showing a natural heat dissipation path in the present embodiment. The first flow 24 is a natural heat dissipation path that enters from the upper air holes 6 and 8 on the left and right side surfaces of the case 2 and is discharged from the air hole 4 on the upper surface of the case 2. These are natural heat dissipation paths that enter from the lower air holes 7, 9, 10 on the lower surface and the left and right side surfaces of the case 2 and are discharged from the upper air holes 5 on the front surface of the case 2.

  Since these two natural heat dissipation paths (first flow 24 and second flow 25) are separated (separated) by the air shielding plate 23, they hardly merge. Therefore, the first flow 24 carries only the heat of the power supply unit 18 located on the flow path, and the second flow 25 carries only the heat of the level converter unit 11 located on the flow path. The above disadvantages, that is, “heat radiation of the power supply unit 18 is not hindered by the air heated by the level converter unit 11”.

  FIG. 4 is a cross-sectional view of the main part of the present embodiment. In this figure, the interior of the housing 1 is composed of a first chamber 27 (chamber) for storing the power supply unit 18 and a second chamber 28 (chamber) for storing the level converter unit 11 and the like by the air shielding plate 23. It is divided into.

  The first chamber 27 communicates with the outside through the air holes 6 and 8 drilled in the upper part of the left and right side surfaces of the case 2 and the air hole 4 drilled in the upper surface of the case 2. The chamber 28 has air holes 7 and 9 formed in the lower portions of the left and right side surfaces of the case 2, an air hole 10 formed in the lower surface of the case 2, and an air hole 5 formed in the upper portion of the front of the case 2. And communicate with the outside world. The heat inside the first chamber 27 is released to the outside by the first flow 24, while the heat inside the second chamber 28 is released to the outside by the second flow 25.

  As described above, according to the present embodiment, the first chamber 27 (the storage chamber for the power supply unit 18) and the second chamber 28 (the storage chamber for the level converter unit 11, etc.) are arranged in the “vertical direction”. In addition to reducing the lateral cross-sectional size of the housing 1 and contributing to the thinning of the housing 1, the natural heat dissipation paths of both the first chamber 27 and the second chamber 28 are independent. By performing (the first flow 24 and the second flow 25), it is possible to obtain a special effect that it is possible not to be affected by the heat in each other's room.

  In this embodiment, the two chambers (first chamber 27 and second chamber 28) are arranged one above the other, and the heat radiation paths (first flow 24 and second flow 25) of the respective chambers are independent. However, it is not limited to this. Two or more chambers may be arranged one above the other and the heat dissipation paths of the respective chambers may be made independent. In short, a unit that requires heat dissipation measures may be accommodated in separate chambers, and the chambers may be partitioned by an air shielding plate 23, and the heat dissipation path for each chamber may be made independent.

  Further, in the present embodiment, the air shielding plate 23 that partitions the first chamber 27 and the second chamber 28 is formed in a cross-section “<” shape, and the details are also understood from FIG. 3 or FIG. 4. As described above, since the cross section of the air shielding plate 23 is formed of the horizontal portion A and the inclined portion B, the narrow portion connected to the second chamber 28 between the inclined portion B and the case 2. C (a chimney part that becomes narrower as it goes upward) is formed, and the presence of this narrow part C promotes the "chimney effect" on the second flow 25, further improving the heat radiation efficiency of the second chamber 28. A desirable effect is possible.

  In the present embodiment, since the air shielding plate 23 that partitions the first chamber 27 and the second chamber 28 is made of a material having an electromagnetic shielding effect (for example, a metal material), the first chamber 27 and the second chamber 28 can also be electromagnetically shielded. For example, the influence of noise from the power supply unit 18 is not exerted on the level converter unit 11 and the electronic boards 19 and 20. The effect that it can do is also acquired.

  In the above-described embodiment, heat accumulated inside the housing 1 is released through the numerous air holes 4 to 10 drilled in each surface of the case 2, but the present invention is not limited to this. Large openings may be provided in place of some of the air holes.

  5 and 6 are a main part external view and a main part sectional view showing another embodiment, and in particular, a diagram showing a large opening 26 instead of the air hole 5 drilled in the front of the case 2. .

  In these drawings, the opening 26 is formed by cutting out the upper part of the front of the case 2 in the lateral direction, and the inside of the housing 1 includes a first chamber 27 for storing the power supply unit 18, a level converter, and the like. It is divided into a second chamber 28 for storing the unit 11 and the like.

  The first chamber 27 communicates with the outside through the air holes 6 and 8 drilled in the upper part of the left and right side surfaces of the case 2 and the air hole 4 drilled in the upper surface of the case 2. The chamber 28 has air holes 7 and 9 drilled in the lower portions of the left and right side surfaces of the case 2, an air hole 10 drilled in the lower surface of the case 2, and an opening 26 formed in the upper front portion of the case 2. Communicate with the outside world.

  Therefore, the heat inside the first chamber 27 is released to the outside by the first flow 24 of the same path as in the above embodiment, while the heat inside the second chamber 28 passes through its discharge port. It is discharged to the outside by a second flow 25 that is an opening 28. The difference from the above embodiment is that the outlet of the second flow 25 is an “opening 26”, and this opening 26 is the air hole 5 (the upper part of the front of the case 2 in the above embodiment). In addition, since it is a large “opening” rather than a mere small hole, there is a specific merit that air resistance can be reduced and its heat dissipation efficiency can be improved.

It is an external view of the signal level adjustment apparatus for a hearing system. It is an internal structure figure of the signal level adjustment apparatus for a common hearing system. It is a figure which shows the flow of the air in this embodiment. It is principal part sectional drawing of this embodiment. It is a principal part external view which shows other embodiment. It is principal part sectional drawing which shows other embodiment.

Explanation of symbols

1 Case (Electronic device case)
2 Case 4 Air hole 5 Air hole 6 Air hole 7 Air hole 8 Air hole 9 Air hole 10 Air hole 11 Level converter unit (component)
18 Power supply unit (component)
23 Air shielding plate 24 First flow (natural heat dissipation path)
25 Second flow (natural heat dissipation path)
26 Opening 27 First chamber (chamber)
28 Second room (room)

Claims (5)

  For electronic equipment, wherein a plurality of components requiring heat dissipation measures are housed in separate chambers, the chambers are arranged in the vertical direction, and the natural heat dissipation path of each chamber is made independent. Enclosure.   The electronic device casing according to claim 1, wherein each of the chambers is partitioned between adjacent chambers by an air shielding plate.   2. The electronic device according to claim 1, wherein each of the chambers is partitioned between adjacent chambers by an air shielding plate, and the air shielding plate is made of a material having an electromagnetic shielding effect. Enclosure.   The electronic device casing according to claim 1, wherein the natural heat dissipation path is formed by a large number of air holes formed in a case of the casing. The electronic device casing according to claim 1, wherein the natural heat dissipation path is formed by a number of air holes formed in a case of the casing and openings formed in the case.

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