JP2010145883A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a possible loss of reliability of a display device caused by a temperature increase in the display device when the display device is set on a wall. <P>SOLUTION: A wall switch 4 disposed in the display device 1 detects attachment of wall metal fittings 3 on the rear surface of the display device 1. When the wall switch 4 detects the wall setup state of the display device 1, a control unit 15 increases a rotational speed of a cooling fan. Thus, the temperature increase in the device in the wall setup state is suppressed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device that displays an image using a plasma display panel (PDP), a liquid crystal display (LCD), or the like, and more particularly to a display device suitable for suppressing a temperature rise of the display device in a wall-mounted state.

  In recent years, display devices such as television receivers have been improved in image quality and large screen in response to digital high-definition broadcasting, and such display devices include a PDP or LCD on a panel display unit for displaying images. Such thin display elements are used. Furthermore, as an installation form of the display apparatus, not only a stationary form in which the display apparatus is supported from below by a television stand but also a form in which the display apparatus is used in a wall-mounted state is known.

  Conventional techniques for dealing with both a stationary installation and a wall-mounted installation of the display device are disclosed in, for example, Patent Document 1 and Patent Document 2.

JP 2006-337776 A JP 2006-337982 A

  A display device (also referred to as a television set or simply a set) includes a PDP or LCD as a display panel, a drive circuit and a power supply circuit for driving the display panel, as described above. Relatively high temperature. For this reason, it is necessary to suitably cool the set to ensure the desired display performance and safety of the set, but the cooling efficiency of the set may differ depending on the installation state of the set.

  For example, in the case of stationary installation with a TV stand, the gap distance between the wall and the back of the TV set is about 10 to 15 cm at the shortest, but in the case of wall mounting, the gap distance between the wall is close to about 2 to 3 cm, for example. Arranged. That is, in the case of wall-mounted installation, compared to stationary installation, the heat dissipation space for convection on the back side of the set (that is, the distance between the back side of the set and the wall surface) is narrow, and the cooling efficiency of the set is reduced. For this reason, in the case of wall-mounted installation, the temperature in the set may rise above the allowable temperature, and the reliability of the display device may be reduced.

  The above-mentioned Patent Documents 1 and 2 do not consider the temperature rise of the set due to the wall mounting of the set.

  The present invention provides a technique suitable for improving the reliability of a display device by suppressing the temperature rise of the display device regardless of the installation state.

  The present invention is characterized in that the rotational speed of a cooling fan in the display device is controlled by detecting whether the display device is wall-mounted or stationary installation. Preferably, when wall-mounted installation is detected as the installation state, control is performed so that the number of rotations of the cooling fan inside the display device is increased as compared with the case of stationary installation.

  The detection of the installation state of the display device may be detection of attachment of a wall hanging member used at the time of wall installation to the back of the display device, or detection of attachment of a stand used at the time of stationary installation to the display device. . Further, the installation state may be detected by measuring the distance between the rear surface of the display device and the wall surface.

  According to the present invention, the number of rotations of the cooling fan can be increased at the time of wall mounting where cooling efficiency is lowered, and the set can be suitably cooled not only at the time of stationary installation but also at the time of wall mounting. Further, the rotational speed of the cooling fan can be lowered during stationary installation, and noise from the cooling fan can be suppressed.

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

  FIG. 1 is a diagram showing two installation states of a display device according to the present invention. FIG. 1A shows a stationary installation state which is a first installation state. A support unit 21 of a television stand 2 is inserted into the lower end portion of the display device (set) 1 and the set 1 is supported from below by the television stand 2. This is the case. In this case, if the stand 2 having a width of about 30 cm is used, the gap S between the back surface of the set 1 and the wall 5 is 10 to 15 cm or more.

  On the other hand, FIG. 1B shows a wall-mounted installation state that is the second installation state, in which the set 1 is fixed to the wall 5 by a wall-hanging metal fitting 3 that is a wall-hanging member. In this case, the gap S between the back surface of the set 1 and the wall 5 is, for example, about 2 to 3 cm. As shown in FIG. 1B, in the case of wall-mounted installation, the clearance (distance) S between the set 1 and the wall surface 5, that is, the heat dissipation space of the set 1 becomes very narrow, and the cooling efficiency of the back region of the set 1 is reduced. Getting worse.

  In the display device according to the present embodiment, an installation state detector is provided in the display device 1 so as to detect whether the display device 1 is in a stationary installation or a wall-mounted installation.

  FIG. 2 is a side view and a rear view showing an embodiment of the display device of the present invention. FIG. 2A is a side view showing a state before the display device (set) 1 is attached to the wall hanging bracket 3, and FIG. 2B is a side view showing a state in which the wall hanging bracket 3 is attached to the set 1. FIG. c) is a rear view showing a state in which the wall mounting bracket 3 is attached to the set 1. The wall mounting bracket 3 is composed of, for example, two support frames 30, and the support frame 30 is attached to the set 1 with the attachment screws 31 and then fixed to the wall 5 with the attachment holes 32.

  In the display device of the present embodiment, a wall-mounted switch 4 that detects that the wall-mounted metal fitting 3 (support frame 30) is attached is provided on the back of the set 1 as an installation state detector. On the other hand, the wall hanging bracket 3 is provided with a protrusion 40 for turning the wall hanging switch 4 ON / OFF at a position facing the wall hanging switch 4. The projecting portion 40 is, for example, a screw incorporated in the support frame 30, and the operating point of the wall-mounted switch 4 can be appropriately adjusted by the protruding amount of the screw tip. One protrusion 40 may be provided corresponding to the wall-mounted switch 4. When the projection 40 is inserted and the wall-mounted switch is turned on, it is determined that the wall-mounted switch is installed. In the OFF state, the wall-mounted metal fitting 3 is not attached. Judge. In this configuration, the protrusion 40 and the support frame 30 are separate members, but the protrusion 40 may be formed integrally with the support frame 30.

  FIG. 3 is a diagram illustrating an example of a circuit configuration of the display device according to the present embodiment. A display device 1 according to this embodiment includes a panel display unit 11, a panel drive circuit 12 that drives the panel display unit, a CPU (central processing circuit) 14 that controls the panel drive circuit 12, and a power supply circuit that supplies power to all of these circuits. 10, a cooling fan 13 for cooling the panel drive circuit 12, the power supply circuit 10, and the like is provided. The CPU 14 includes a control unit 15 that controls the panel drive circuit 12, the cooling fan 13, and the like, and a data memory 19 that stores control data. In the present embodiment, the detection signal from the wall-mounted switch 4 is input to the control unit 15 to control the cooling fan 13 of the panel drive circuit and the power supply circuit. That is, when it is detected from the signal of the wall-mounted switch 4 that the set 1 is in the wall-mounted state, the control unit 15 increases the rotation speed of the cooling fan 13. If the wall-mounted switch 4 does not detect the wall-mounted state, it is determined as a stationary state and the rotation speed of the cooling fan 13 is not changed.

  FIG. 4 is a diagram showing an example of the layout viewed from the back side in the case of the PDP display device. In the case of a PDP display device, the panel drive circuit 12 that drives the panel display unit 11 (PDP) on the front surface includes an X sustain circuit 18x, a Y sustain circuit 18y, and an address circuit 17. The address circuit 17 accumulates wall charges on a predetermined address electrode, and the sustain circuits 18x and 18y maintain light emission for a predetermined period. The digital signal circuit 16 includes the CPU 14. The digital signal circuit 16 converts an image signal input from the outside or an image signal from a tuner (not shown) into display data of the panel display unit 11 and supplies it to the address circuit 17 and the X and Y sustain circuits 18x and 18y. To do. These circuits are supplied with the necessary voltage by the power supply circuit 10. In the PDP display device, the X and Y sustain circuits 18x and 18y and the power supply circuit 10 are heat sources. Cooling fans 13A, 13B, and 13C are arranged in the vicinity of these heat sources.

  As for the rotational speed of the cooling fans 13A, 13B, and 13C, the relationship between the rotational speed and the temperature of the cooling fans 13A, 13B, and 13C in the wall-mounted installation state and the stationary installation state is measured in advance, and the optimum cooling The rotational speed and supply voltage of the fans 13A, 13B, and 13C are determined in advance. The installation state of the set 1 is judged by the wall mounted switch 4, and the control unit 15 in the digital signal circuit 16 controls the cooling fans 13A, 13B, 13C so that the rotational speed of the cooling fans 13A, 13B, 13C becomes an optimum value. The supply voltage is controlled. The set value of the supply voltage is stored in the data memory 19.

  For example, in a 50-inch PDP, it is preferable to control the rotation speed of the cooling fans 13A, 13B, and 13C to about 1800 rpm in the stationary state when the stand is attached and to about 2200 rpm in the wall-mounted state when the wall bracket 3 is attached. However, it became clear by examination of the present inventors. Therefore, in the data memory 19, the rotation speed of the cooling fan corresponding to each installation state and the data of the voltage setting value of the cooling fan are stored in advance in association with each other, and this is detected by the detection signal from the wall-mounted switch 4. Accordingly, the rotational speed may be controlled by selectively reading out and adjusting the supply voltage to the cooling fan.

  FIG. 5 shows an example of a layout viewed from the back side in the case of an LCD display device. The digital signal circuit 53 includes the CPU 14. The digital signal circuit 53 converts an image signal input from the outside or an image signal from a tuner (not shown) into display data of the panel display unit 11 (LCD). Based on the video signal from the digital signal circuit 53, the logic circuit 50 drives the panel display unit 11 (LCD). That is, in the LCD display device, the panel drive circuit 12 is the logic circuit 50. The inverter circuit 51 generates a backlight lighting voltage. The necessary voltage is supplied to these circuits by the power supply circuit 50. In the case of the LCD display device, since the heat source is the power supply circuit 50, the cooling fan 13D is disposed in the vicinity of the power supply circuit 50.

  As in the case of the above PDP display device, the relationship between the rotational speed and the temperature of the cooling fan 13D in the wall-mounted installation state and the stationary installation state is measured in advance, and the optimal rotational speed and supply voltage of the cooling fan 13D are measured. Decide. In the same manner as described above, the rotation speed of the cooling fan corresponding to each installation state and the data of the set voltage value of the cooling fan are stored in the data memory 19 in association with each other. Based on the detection signal from the wall-mounted switch 4, the set voltage data corresponding to the installation state of the set 1 is read from the data memory 19, so that the rotation speed of the cooling fan 13 </ b> D becomes the optimum value in the digital signal circuit 53. The control unit 15 controls the supply voltage to the cooling fan 13D.

  In the case of an LCD display device, in a stationary installation state, there are many cases where the temperature is equal to or lower than the allowable temperature without rotating the cooling fan 13D. In that case, the rotation of the cooling fan 13D may be stopped in the stationary installation state when the stand is attached, and the cooling fan 13D may be rotated in the wall-mounted installation state when the wall hanging bracket 3 is attached.

  FIG. 6 is a flowchart of the cooling fan rotation speed control process of the display device according to the present embodiment.

  When the power of the display device (set) 1 is turned on, this processing is started (S101). At the same time as the image display is started, a signal (ON / OFF signal) from the wall-mounted switch 4 of the set 1 is detected in S102. In S103, the signal of the wall-mounted switch 4 is determined. If the switch is ON, it is determined that the wall-mounted switch is installed. In S104, the control unit 15 increases the rotation speed of the cooling fan 13. If the switch is OFF, it is determined that the device is installed in the stationary state, and the cooling fan 13 is rotated at the normal rotational speed (the optimum rotational speed in the stationary state) in S105.

The embodiment described above is a basic configuration and operation, and the following modifications are possible.
[Modification 1] As an installation state detector, a television stand detector that detects whether the set 1 is supported by the television stand 2 may be used instead of the wall-mounted switch 4. FIG. 7 shows an example of a television stand detector. A pinhole 22 is provided on the panel display unit 11 side in the vicinity of the position where the support unit 21 of the television stand 2 at the lower end of the set is inserted, and light for detecting light leakage from the panel display unit 11 on the side opposite to the panel display unit 11 A sensor (television stand detector) 23 is provided. And it is good also as a structure which detects the presence or absence of the television stand 2 by blocking the light leakage from the panel display part 11 to the optical sensor 23 by inserting the support part 21. In this case, when the installation of the television stand 2 is detected by the optical sensor 23, it is determined as a stationary installation state, and when the installation of the television stand 2 is not detected, it is determined as a wall-mounted installation state. The contents of the subsequent processing are the same as those described above.
[Modification 2] FIG. 8 shows an example of installation when the set 1 is attached to the wall 5 in an inclined manner and an example of control of the fan rotation speed in accordance with the inclination angle θ.

FIG. 8A is a diagram when the set 1 is attached to the wall 5 while being inclined. In this case, since the gap with the wall 5 is widened at the upper part of the set 1 and the cooling efficiency is improved, the temperature rise is smaller than that in the state of FIG. Therefore, in this modification, an angle sensor or the like is attached to the inside of the set 1, and the amount of inclination (inclination angle θ) of the set 1 is detected by this angle sensor. For example, as shown in FIG. The supply voltage is controlled by the control unit 15 so as to decrease the rotational speed of the cooling fan 13 as the inclination angle increases. Here, FIG. 8B shows an example in which the rotation of the cooling fan 13 is stopped at an inclination angle of 90 °, and FIG. 8C shows the number of rotations of the cooling fan 13 in an inclination angle range of 0 to 90 °. It shows a case where the rotation speed is changed between the optimum rotation speed at the time of wall installation and the optimum rotation speed at the time of stationary installation. Any control characteristic may be used as necessary. Thus, in this modification, the number of rotations of the cooling fan can be controlled according to the inclination angle with respect to the wall surface of the set 1, and the rotation speed of the cooling fan 13 is determined according to the inclination amount (inclination angle) of the set 1. If the configuration is changed continuously or intermittently, it is possible to control the rotational speed of the cooling fan 13 finely.
[Modification 3] Instead of the wall-mounted switch 4, a distance sensor for measuring the distance from the back surface of the set 1 to the wall surface may be provided on the back surface of the set 1 as an installation state detector. For example, when the gap S between the back surface of the set 1 measured by the distance sensor and the back surface and the wall 5 is a predetermined value (for example, 2 cm) or less, it is detected or determined that the set 1 is in a wall-mounted state, As described above, the rotational speed of the cooling fan 13 is controlled so as to increase compared to the stationary installation state. On the other hand, when the interval S measured by the distance sensor exceeds a predetermined value, it is detected or determined that the set 1 is in the stationary installation state, and the rotation speed of the cooling fan 13 is set to the normal value (in the stationary installation state). Optimal rotation speed).
[Modification 4] Further, immediately after the set power is turned on, the temperature in the set 1 is usually low, so even when the wall-mounted installation state is detected, the cooling fan 13 does not necessarily need to be started or increased in rotational speed.

  Therefore, for example, as shown in FIG. 9 (a), the cooling fan 13 is stopped within a predetermined time (t) immediately after turning on the power of the set 1 in both the wall-mounted installation and the stationary installation. The cooling fan may be started after elapse of t). Further, as shown in FIG. 9 (b), when installing on the wall, during the predetermined time (t) immediately after turning on the power of the set 1, the number of rotations of the cooling fan 13 is set at a preset number of rotations when installed on the wall. The number of rotations of the cooling fan may be increased after a predetermined time (t) and the rotation number at the time of wall mounting set in advance may be set.

  The predetermined time (t) may be counted by a timer (not shown). In other words, a timer may be activated when the set 1 is turned on, and a control signal may be output to the control unit 15 to perform the above-described control when the timer is counted for a predetermined time (t).

  According to this modified example, the rotation of the cooling fan is stopped or the number of rotations is reduced from the start of the set 1 to the elapse of a predetermined time (t) by the timer, so that the power supply of the set that does not require much cooling. Immediately after being turned on, the operation of the fan can be suppressed, and the noise caused by the rotation of the cooling fan 13 can be suppressed.

  As described above, according to the configuration of this embodiment, the installation state of the marking device 1 is detected by the installation state detector, and when the wall-mounted installation state is detected, the control unit 15 sets the rotation speed of the cooling fan 13. Since the control is performed so that it is raised (compared to the stationary installation state), the display device can be suitably cooled even in the case of wall-mounted installation where the cooling efficiency is lowered. Further, when the stationary installation state is detected, the control unit 15 can also control to reduce the number of rotations of the cooling fan. Therefore, according to the present embodiment, it is possible to improve the reliability of the display device by suppressing the temperature rise particularly when installed on the wall regardless of the installation state of the display device. In addition, it is possible to reduce noise generated from the cooling fan by suppressing the operation of the cooling fan.

  The display device of the present invention can be widely applied to a wall-mountable display device using a thin display element such as a PDP or an LCD.

The figure which shows the two installation states of the display apparatus which concerns on this invention. The side view and back view which show one Example of the display apparatus which concerns on this invention. FIG. 6 is a diagram illustrating an example of a circuit configuration of a display device according to an embodiment. The figure which shows an example of the layout which looked at the PDP display device which concerns on a present Example from the back side The figure which shows an example of the layout which looked at the LCD display apparatus based on a present Example from the back side Flowchart showing cooling fan rotation speed control of the display device of the present embodiment The figure which shows an example of a structure of a stand sensor The figure which shows an example which showed the example of installation at the time of attaching the set 1 to the wall 5, and the control of the fan rotational speed according to inclination-angle (theta) The figure which shows an example of the rotation speed control of the cooling fan immediately after starting of a set

Explanation of symbols

1. Display device (set)
2 ... TV stand 3 ... Wall mount 4 ... Wall mount switch 5 ... Wall 10 ... Power supply circuit 11 ... Panel display unit 12 ... Panel drive circuit 13 ... Cooling fan 14 ... CPU
DESCRIPTION OF SYMBOLS 15 ... Control part 16 ... Digital signal circuit 17 ... Address circuit 18 ... Sustain circuit 19 ... Data memory 21 ... Support part 22 ... Pinhole 23 ... Television stand detection sensor 30 ... Support frame 31 ... Mounting screw 40 ... Projection part 50 ... Logic Circuit 51 ... Inverter circuit 53 ... Digital signal circuit

Claims (14)

In a display device that displays an image,
An installation state detector for detecting whether the display device has a first installation state in which the distance between the back surface and the wall surface of the display device is a predetermined distance or a second installation state shorter than the predetermined distance;
A cooling fan for cooling the display device;
A control unit for controlling the rotational speed of the cooling fan,
The display device according to claim 1, wherein the controller controls the cooling fan rotation speed in accordance with a detection result of the installation state detector. The display device according to claim 1,
The first installation state is a stationary installation state in which the display device is stationaryly installed using a stand for supporting the display device from below, and the second installation state is a wall hanging in which the display device is provided with a wall hanging member. A display device characterized by being in an installed state. The display device according to claim 2,
The installation state detector detects that the display device is in the second installation state when the wall hanging member is attached to the display device, and displays the display device when the wall hanging member is not attached. A display device that detects the first installation state. The display device according to claim 2,
The installation state detector detects that the display device is in the first installation state when the stand is attached to the display device, and if the stand is not attached, the display device is the first display device. 2. A display device that detects an installed state. The display device according to claim 1,
The installation state detector is a distance sensor for measuring a distance between a back surface and a wall surface of the display device, and when the distance measured by the distance sensor exceeds a predetermined value, the display device is A display device, wherein the display device is detected as being in the first installation state, and when the interval measured by the distance sensor is equal to or less than a predetermined value, the display device is detected as being in the second installation state. The display device according to claim 1,
The display device according to claim 1, wherein when the installation state detector detects the second installation state, the control unit increases the number of rotations of the cooling fan more than when the first installation state is detected. The display device according to claim 5,
Data relating to the first rotation speed corresponding to the first installation state and data relating to a second rotation speed corresponding to the second installation state and higher than the first rotation speed are determined in advance. And
When the installation state detector detects the first installation state, the control unit controls the number of rotations of the cooling fan based on the data related to the first rotation number, and when the second installation state is detected. The display device characterized in that the number of rotations of the cooling fan is controlled from data relating to the second number of rotations. The display device according to claim 6,
A display device further comprising a timer for starting the cooling fan or increasing the number of rotations of the cooling fan after a predetermined time has elapsed after the display device is turned on. In a display device that displays an image,
An installation state detector for detecting that a wall mounting bracket is attached to the back side of the display device;
A cooling fan disposed inside the display device;
A control unit for controlling the rotational speed of the cooling fan,
The said control part is a display apparatus which controls the said cooling fan rotational speed according to the detection result of the said installation state detector. The display device according to claim 9, wherein
The control unit controls to increase the rotation speed of the cooling fan when the installation state detector detects that the wall mounting bracket is attached, compared to a case where the installation is not detected. apparatus.   10. The display device according to claim 9, wherein when the inclination angle of the display device with respect to the wall surface is variable when the display device is mounted on the wall, the control means controls the fan rotation speed according to the inclination angle. A display device characterized by that. In a display device that displays an image,
An installation state detector for detecting that a stand for supporting the display device from below is attached to the display device;
A cooling fan disposed inside the display device;
A control unit for controlling the rotational speed of the cooling fan,
The said control part is a display apparatus which controls the said cooling fan rotational speed according to the detection result of the said installation state detector. The display device according to claim 4,
When the installation state detector detects that the stand is attached, the control unit performs control so as to reduce the rotation speed of the cooling fan compared to the case where the stand is not detected. . In a display device that displays an image,
An installation state detector for detecting whether the display device is a wall-mounted installation state or a stationary installation state;
A cooling fan for cooling the display device;
A control unit for controlling the rotational speed of the cooling fan,
When the installation state detector detects a wall-mounted installation in the previous period, the control unit controls the rotation speed of the cooling fan to be higher than that when the stationary installation is detected. .

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