JP2011192701A - Light shielding plate for electronic device, electronic device, and heat radiation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light shielding plate for outdoor-installed electronic device by which heat radiation efficiency is improved as compared with a conventional technology. <P>SOLUTION: The light shielding plate for the electronic device includes a plurality of light shielding fins. Each light shielding fin can turn around a turning axis. By turning each light shielding fin, the light shielding plate can be set in a first state or a second state. In the second state, a spacing between the respective light shielding fins becomes large as compared with the first state. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a light shielding plate that prevents the temperature in an electronic device installed outdoors from rising due to solar radiation.

  The housing of electronic equipment that must be installed outdoors, such as wireless communication equipment and broadcasting equipment, prevents water from entering the interior and effectively induces and emits heat from the internal electronic circuits to the outside. There is a need. Here, in order to suppress the temperature rise in the housing due to solar radiation, a configuration in which a light shielding plate is arranged around the housing has been proposed (for example, see Patent Document 1).

JP 2009-231784 A

  FIG. 6 is a cross-sectional view for explaining a configuration according to the prior art. In FIG. 6, reference numeral 1 denotes a housing that houses an electronic circuit therein, and reference numeral 11 denotes heat dissipation of the housing 1 for increasing the contact area between the housing 1 and the outside air to enhance the heat dissipation effect. 2 is a light shielding plate. The light shielding plate 2 prevents the housing 1 from being irradiated with sunlight, thereby suppressing a temperature rise due to the sunlight of the housing 1. Although the temperature of the light shielding plate 2 itself is increased by irradiation with sunlight, the light shielding plate 2 is attached to the housing 1 using a heat insulating member in order to prevent heat conduction from the light shielding plate 2 to the housing 1. FIG. 6 shows a configuration for one surface of the housing 1, but actually, the light shielding plate 2 is provided for all surfaces that receive solar radiation.

  The light shielding plate 2 can prevent the casing 1 from rising in temperature due to solar radiation, but the light shielding plate 2 has a problem of restricting convection of air heated by the heat radiating portion 11 of the housing 1. In particular, there is a problem that the heat radiation efficiency is deteriorated by the light shielding plate 2 on the surface not irradiated with sunlight.

  Therefore, an object of this invention is to provide the light-shielding plate for electronic devices, an electronic device, and the heat dissipation method which improve heat dissipation efficiency from a prior art.

According to the light shielding plate of the present invention,
A light shielding plate for an electronic apparatus including a plurality of light shielding fins, wherein each light shielding fin is rotatable about a rotation axis, and the light shielding plate is moved to a first state by rotating each light shielding fin. The second state is characterized in that the gap between the light shielding fins is larger than that in the first state.

According to another embodiment of the light shielding plate of the present invention,
In the second state, it is also preferable that at least one light shielding fin is in contact with a casing of the electronic device.

Further, according to another embodiment of the light shielding plate of the present invention,
The rotation axes of the light shielding fins are parallel to each other, and the radial length of the light shielding fin with respect to the rotation axis is preferably equal to or greater than the distance between the rotation axis and the rotation axis of the adjacent light shielding fin.

Further, according to another embodiment of the light shielding plate of the present invention,
It is preferable to include a driving unit that switches between the first state and the second state, and further includes a measuring unit that measures the amount of solar radiation and a control unit that controls the driving unit according to the amount of solar radiation. It is also preferable.

According to the electronic device of the present invention,
The light shielding plate is included.

According to the heat dissipation method of the present invention,
A heat dissipation method for an electronic device including a light shielding plate that can be set to a first state and a second state, wherein light that can pass through the light shielding plate in the first state is the second state. The light shielding plate facing the surface of the electronic device that receives solar radiation is set to the first state, and the light shielding plate facing the surface of the electronic device that is not exposed to solar radiation is set to the second state. And

According to another embodiment of the heat dissipation method of the present invention,
A heat dissipation method for an electronic device including a light shielding plate that can be set to a first state and a second state, wherein light that can pass through the light shielding plate in the first state is the second state. When the electronic device is exposed to solar radiation, all the light shielding plates are set to the first state, and when there is no solar radiation to the electronic device, all the light shielding plates are set to the second state. It is also preferable.

According to another embodiment of the heat dissipation method of the present invention,
In the second state, it is also preferable that the light shielding plate is thermally connected to a housing of the electronic device.

  By setting the second state to the surface of the electronic device that does not have solar radiation, the light shielding plate can be prevented from restricting convection, thereby improving the heat dissipation efficiency. Furthermore, in the second state, by bringing the light shielding fins of the light shielding plate into contact with the housing of the electronic device, the heat dissipation area of the electronic device can be expanded, and the heat dissipation efficiency can be improved.

It is a side view of the light-shielding plate by this invention. It is a front view of the light-shielding plate by this invention. It is a figure which shows the state of the light-shielding plate when there exists solar radiation. It is a figure which shows the state of the light-shielding plate when there is no solar radiation. It is a schematic block diagram of a light-shielding plate drive device. It is a figure which shows the structure by a prior art.

  EMBODIMENT OF THE INVENTION The form for implementing this invention is demonstrated in detail below using drawing. FIG. 1 is a side view of a light shielding plate according to the present invention, and FIG. 2 is a front view of the light shielding plate according to the present invention. As shown in FIGS. 1 and 2, the light shielding plate includes a plurality of light shielding fins 21, a plurality of light shielding fin attachment portions 22, a frame portion 23, and a light shielding plate attachment portion 24.

  Each light shielding fin attachment portion 22 is attached to the frame portion 23 so that the light shielding fin attachment portion 22 can rotate around the center in the longitudinal direction and the rotation shafts of the light shielding fin attachment portions 22 are parallel to each other. In addition, one light-shielding fin 21 is attached to the light-shielding fin mounting portion 22, and the light-shielding fin 21 is rotatable about the rotation axis of the light-shielding fin mounting portion 22. Hereinafter, the direction of the rotation axis of each light shielding fin 21 is referred to as a horizontal direction, and the direction perpendicular to each rotation axis in a plane including the rotation axis of each light shielding fin 21 is referred to as a vertical direction. That is, the longitudinal direction of the frame 23 in FIG. In the present invention, the length of the light shielding fin 21 in the horizontal direction is substantially the same as the length of the opposing surface of the casing of the electronic device.

  Further, the frame portion 23 is connected to the light shielding plate mounting portion 24 at both ends in the vertical direction, and the light shielding plate according to the present invention is connected to the housing of the electronic device by the light shielding plate mounting portion 24, and the electronic device according to the present invention. Configure the equipment. In order to thermally insulate the light shielding plate from the housing, a heat insulating material is used for the light shielding plate mounting portion 24.

  3 and 4 show two states of the light shielding plate / electronic device according to the present invention. 3 and 4 are views of the light shielding plate as viewed from the side, and the frame portion 23 is omitted for simplicity. In the first state shown in FIG. 3, the surface extending perpendicularly from the rotation axis of each light shielding fin 21 is placed at a position approaching a plane including the rotation axis of each light shielding fin 21. In the first state, the gap between the light shielding fins 21 is hardly visible at least from the direction of the sun on the opposite side of the heat radiating portion 11 with respect to the light shielding plate. From the side opposite to the heat radiating part 11 of the body, light that passes through the light shielding plate and travels toward the heat radiating part 11 is completely or largely blocked, for example, 80% or more. For this reason, the length in the radial direction of the light shielding fin 21 that rotates about the rotation axis is preferably equal to or greater than the distance between the rotation axis of the light shielding fin 21 and the rotation axis of the adjacent light shielding fin 21. In the first state, the length of the light shielding fins 21 in the radial direction and the distance to the heat radiation part 11 of the housing are set so that each light shielding fin 21 does not have a contact with the heat radiation part 11 of the housing.

  On the other hand, in the second state shown in FIG. 4, the surface extending perpendicularly from the rotation axis of each light shielding fin 21 is located away from the plane including the rotation axis of each light shielding fin 21. In the second state, the gap between the light shielding fins 21 appears to be larger from the direction of the sun on the side opposite to the heat radiating part 11 with respect to the light shielding plate. Of the light that passes through the light shielding plate and travels toward the heat radiating portion 11, light other than the portion that is inevitably blocked by the light shielding fin mounting portion 22 and the light shielding fin 21 reaches the heat radiating portion 11. That is, in the second state, the light shielding plate does not actively block the light passing therethrough, and the light reaching the heat radiating portion 11 is increased from the first state. In the second state, at least one light shielding fin 21, preferably all the light shielding fins 21, have a contact point with the heat radiating part 11 of the housing. For this reason, the length of the light shielding fin 21 on the side of the heat radiating portion 11 from the rotation axis in the radial direction is longer than the distance to the heat radiating portion 11.

  The first state shown in FIG. 3 is a state that is set when there is solar radiation. In the first state, like the conventional light shielding plate, solar radiation to the housing is prevented and the temperature inside the housing is increased. suppress. On the other hand, the second state shown in FIG. 4 is a state set when there is no solar radiation. In the second state, the gap between the light shielding fins 21 is made larger than that in the first state to block the light. While removing the restriction | limiting of the convection by a board and making each light shielding fin 21 and the thermal radiation part 11 contact, each light shielding fin 21 is also operated as a thermal radiation part.

For example, the surface area of the heat radiating portion 11 is ¹⁰⁶ square millimeters when the thermal resistance in the case of allowing a temperature rise of 50 ° C. is 1 ° C. / W, by causing the respective light-shielding fin 21 is radiated portion 11 and the thermal connection If the surface area is doubled, the thermal resistance is reduced to 0.6 ° C./W. In the present invention, since the gap between the light shielding plates is further increased, the convection is increased, and thus the heat radiation efficiency is further improved. For this reason, the light shielding fin 21 is made of a material having a relatively high thermal conductivity, for example, the same material as that used for the heat radiation unit 11. Specifically, for example, in order to improve the thermal emissivity, a metal material such as an aluminum material whose surface is subjected to black alumite treatment can be used. Further, it is preferable that the heat radiating portion 11 is provided with a protruding portion as shown in FIGS. 3 and 4 and the protruding portion and the light shielding fin 21 are brought into contact with each other to increase the contact area between the protruding portion and the light shielding fin 21.

  The state change of the light shielding plate according to the present invention may be performed manually, but may be automatically performed using the light shielding plate driving device. FIG. 5 is a schematic configuration diagram of the light shielding plate driving device, which includes a solar radiation amount detection unit 31, a control unit 32, and a driving unit 33. In addition, what is necessary is just to attach the light-shielding plate drive device to arbitrary positions, such as the frame 23, the member which is not shown in figure which connects between two frames, and also an electronic device.

  The solar radiation amount detection unit 31 measures the solar radiation amount and outputs a measurement value to the control unit 32. The control unit 32 determines whether there is solar radiation on the housing depending on whether the measurement value is larger than a threshold value, and the determination result Accordingly, the drive unit 33 is driven to change the state of the light shielding plate. With this configuration, the light shielding plate can be automatically controlled. In the above description, only one surface of the housing and the light shielding plate facing the surface are shown. However, in practice, the same configuration is applied to all surfaces of the housing that receive solar radiation. use. At this time, the light-shielding plate facing each surface of the housing may be controlled so as to be in the same state, but it is preferable to control the light-shielding plates independently. In the case of independent control, for example, the light shielding plate facing the surface of the housing that receives solar radiation is set to the first state, and the light shielding plate facing the surface not receiving solar radiation on the opposite side is set to the second state. This makes it possible to improve the heat dissipation efficiency even during the daytime. In addition, when controlling the light shielding plate facing each surface of the housing independently, the solar radiation amount detection unit 31 is attached to each light shielding plate, measures the amount of solar radiation on the attached light shielding plate, When not controlling independently, the solar radiation amount detection part 31 is installed in the position which can determine reliably the presence or absence of solar radiation, such as the upper part of a housing | casing, for example.

  Furthermore, it is not only controlled by the amount of solar radiation but also controlled by time, or configured to connect the light shielding plate driving device to the network and controlling the state of the light shielding plate by a remote control signal. Also good. Further, the light shielding plate according to the present invention is connected to the housing by the light shielding plate mounting portion 24. However, it is sufficient that the light shielding plate can be installed to face each surface of the housing, and the light shielding plate is in the first state. As long as heat is not transmitted to the housing in step 1, the light shielding plate may be fixed by any method.

DESCRIPTION OF SYMBOLS 1 Case 2 Light-shielding plate 11 Heat-radiating part 21 Light-shielding fin 22 Light-shielding fin attaching part 23 Frame part 24 Light-shielding plate attaching part 31 Solar radiation amount detection part 32 Control part 33 Drive part

Claims (9)

A light shielding plate for an electronic device including a plurality of light shielding fins,
Each light shielding fin is rotatable about a rotation axis,
By rotating each light shielding fin, the light shielding plate can be set to the first state and the second state,
In the second state, the gap between the light shielding fins is larger than that in the first state.
Shading plate. In the second state, at least one light shielding fin is in contact with a housing of the electronic device.
The light shielding plate according to claim 1. The rotation axes of the light shielding fins are parallel to each other,
The length in the radial direction with respect to the rotation axis of the light shielding fin is not less than the distance between the rotation axis and the rotation axis of the adjacent light shielding fin.
The light shielding plate according to claim 1.   The light-shielding plate of any one of Claim 1 to 3 provided with the drive means which switches the said 1st state or the said 2nd state. A measuring means for measuring the amount of solar radiation;
Control means for controlling the drive means according to the amount of solar radiation;
The light-shielding plate according to claim 4, comprising:   An electronic device including the light shielding plate according to claim 1. A heat dissipation method for an electronic device including a light shielding plate that can be set to a first state and a second state,
In the first state, light that can pass through the light shielding plate is reduced from that in the second state,
The light shielding plate that faces the surface of the electronic device that receives solar radiation is in the first state, and the light shielding plate that faces the surface of the electronic device that does not receive solar radiation is in the second state.
Heat dissipation method. A heat dissipation method for an electronic device including a light shielding plate that can be set to a first state and a second state,
In the first state, light that can pass through the light shielding plate is reduced from that in the second state,
When there is solar radiation to the electronic device, all the light shielding plates are in the first state, and when there is no solar radiation to the electronic device, all the light shielding plates are in the second state.
Heat dissipation method. In the second state, the light shielding plate is thermally connected to the housing of the electronic device.
The heat dissipation method according to claim 7 or 8.

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