JPH1138934A - Safety device for pdp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means to secure safety by promptly cutting off a power source even when a PDP(plasma display panel) is damaged by overturning, etc. SOLUTION: A piezoelectric sensor 1 is mounted to connect with a discharge cell of PDP opened to a PDP. An electric signal from pressure sensor 1 showing a gas pressure in PDP is amplified by an amplifier 2, and the pressure signal S1 is compared with a constant comparison voltage S2 generated by a comparison voltage generation circuit 4 by a comparison circuit 3. This comparison voltage S2 is made to be a middle value between a value corresponding to a normal pressure of PDP and a value corresponding to the atmospheric pressure. Since the normal pressure of PDP is lower than the atmospheric pressure, the pressure signal S1 rises up to a value corresponding to the atmospheric pressure when PDP is damaged by overturning, etc. The comparison circuit 3 outputs a damage signal S3 when the pressure signal S is higher than the comparison voltage S2. This damage signal S3 drives a control circuit 5 for controlling a power source 6 of PDP to cut off the power source 6 of PDP.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PDP (Plasma Display Panel) used as a display for television images and the like, which can prevent accidents such as fire due to the power supply of the PDP even if the PDP is damaged due to a fall or the like. Related to the device.

[0002]

2. Description of the Related Art PDPs have been widely used as display devices capable of displaying television images and the like on a thin and large screen. Since the PDP performs light-emitting display by discharging a discharge gas, a relatively high voltage of about 200 V is used. Therefore, safety measures such as detecting an abnormal current and turning off the power supply are taken in preparation for the case where the electrode of the PDP is short-circuited. However, when the PDP falls over due to an earthquake or the like, the PDP may be damaged, and the electrodes may come into contact with external objects, causing ignition, smoking, or the like. In addition, there is a risk of electric shock if the bare electrode is touched. As a safety measure, it is desirable to prepare for such an emergency.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a means for quickly turning off the power supply and ensuring safety even when a PDP is damaged due to a fall or the like. And

[0004]

Means for Solving the Problems By detecting the damage of the PDP by using a pressure sensor or the like for detecting the pressure of the discharge cell of the PDP, the power supply for driving the PDP is cut off by a signal indicating the detected damage. Even if the PDP is damaged due to a fall or the like, the power is immediately cut off to ensure safety.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a display using a PDP (plasma display panel), a damage means for detecting damage to the PDP and outputting a damage signal, and a power supply disconnecting means for driving the PDP based on the detected damage signal And the same P
When the DP is damaged, the power supply is cut off.

[0006] The damage detecting means is a pressure sensor for detecting the pressure in the discharge cell of the PDP, and detects the damage of the PDP based on the fluctuation of the pressure.

[0007] The damage detecting means is provided with a discharge electrode for discharging in the discharge cell of the PDP, and detects a damage of the PDP by a change in discharge current of the discharge electrode.

The discharge electrode is a pilot discharge electrode of the PDP.

[0009]

FIG. 1 shows a safety device for a PDP according to the present invention.
It is a principal part block diagram of an Example. A PDP (not shown) that displays a television image or the like by using a diaphragm-type or piezoelectric-type piezoelectric sensor 1 that converts gas pressure into an electric signal.
It is connected to and attached to a discharge cell (referred to as a discharge space for light emission of the PDP) of the PDP that is opened at the bottom. An electric signal indicating the gas pressure in the PDP from the pressure sensor 1 is amplified by the amplifier circuit 2, and the pressure signal S 1 is compared with a constant comparison voltage S 2 generated by the comparison voltage generation circuit 4 by the comparison circuit 3.
The comparison voltage S2 is set to an intermediate value between the value corresponding to the normal PDP pressure and the value corresponding to the atmospheric pressure. Normal PD
Since P is lower than the atmospheric pressure, if the PDP is damaged due to a fall or the like, the pressure signal S1 rises to a value corresponding to the atmospheric pressure. In the comparison circuit 3, the pressure signal S1 is compared with the comparison voltage S2.
When it becomes higher, a damage signal S3 is output. The control circuit 5 for controlling the power supply 6 of the PDP is driven by the damage signal S3 to turn off the power supply 6 of the PDP.

FIG. 2 is a schematic diagram of a damaged signal detector of another embodiment of the PDP safety device according to the present invention. PDP1
0, a discharge electrode 12 for damage detection is provided.
Discharge with pulse voltage from 1. A resistor 21a having a low resistance value is inserted into the discharge circuit, and the voltage between both ends is rectified by a diode 21b, a resistor 21c, a capacitor 21d, and the like to obtain a DC output voltage S21. When PDP is normal,
Discharge occurs in the discharge electrode 12, and a constant output voltage S21 is obtained. If the PDP is damaged due to overturning or the like, air flows into the discharge cells 10a of the PDP 10 filled with the discharge gas, and the discharge stops. Therefore, at this time, the output voltage S21 becomes 0. By setting the output voltage S21 to a predetermined voltage in the amplifier circuit 22 and negating in the NOT circuit 23, the above-described damaged signal S3 is obtained. Although the discharge electrode 12 for damage detection may be provided separately, the PDP is used to accelerate the ignition of the PDP.
During use, it is also possible to divert a pilot discharge electrode which constantly discharges.

[0011]

As described above, damage to a PDP is detected using a pressure sensor or the like that detects the pressure of a discharge cell of the PDP, and a power supply for driving the PDP is cut off based on a signal indicating the detected damage. As a result, even if the PDP is damaged due to a fall or the like, the power supply is immediately turned off, so that even if the PDP is damaged and the electrodes come into contact with an external object, there is no danger of ignition or smoking. , Safety is ensured. Also. The exposed electrode eliminates the risk of electric shock and the like.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of an embodiment of a PDP safety device according to the present invention.

FIG. 2 is a schematic view of a damaged signal detection unit of another embodiment of the PDP safety device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure sensor 2 Amplification circuit 3 Comparison circuit 4 Comparison voltage generation circuit 5 Control circuit 6 Power supply 10 PDP 11 Discharge power supply 12 Discharge electrode 21a, 21c Resistance 21b Diode 21d Capacitor 22 Amplification circuit 23 Negation circuit S3 Damage signal

Claims (4)

[Claims] 1. PDP (Plasma Display Panel)
The display using the PDP includes damage detection means for detecting damage to the PDP and outputting a damage signal, and power supply disconnecting means for driving the PDP based on the detected damage signal.
PDP that turns off the power supply when P is damaged
Safety equipment. 2. The PDP according to claim 1, wherein said breakage detecting means is a pressure sensor for detecting a pressure in a discharge cell of said PDP, and detects a breakage of said PDP by a change in said pressure. Safety equipment. 3. The damage detecting means is provided with a discharge electrode for performing discharge in a discharge cell of the PDP, and detects breakage of the PDP based on a change in discharge current of the discharge electrode. The safety device according to claim 1. 4. The safety device according to claim 3, wherein the discharge electrode is a pilot discharge electrode of the PDP.