JPH0834680B2 - Power switch control circuit - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power switch control circuit of an electric device equipped with a remote control device capable of remotely controlling on / off of a power source of a device body, for example, a television receiver. And so on.

2. Description of the Related Art Conventionally, a power switch control circuit of a television receiver provided with a remote control device has been as shown in FIG. That is, the first switch 2 and the control circuit 3 are connected to the commercial power source 1, and the first switch 2
A second switch (relay) 5 whose switching is controlled by the control circuit 3 is connected between the load circuit 4 and the load circuit 4. The control circuit 3 also controls the operation of the receiving unit 8 which receives the signal from the remote control oscillator 7, and the receiving unit 8 receives the signal from the remote control oscillator to turn on the power of the apparatus. When judged by the output from 8, the control means 3 controls the second switch 5 to close it.

Further, 9 is a sub-power switch that has the same function as the power on / off operation by the remote control device. By operating this sub-power switch 9, the control circuit 3 is operated by the receiving unit 8 from the remote control device. The relay 5 is closed in the same manner as when the ON signal is received. In this way, the television receiver can be turned on and off without using the remote control transmitter.

Problems to be Solved by the Invention In order for a user to set a television receiver having such a circuit to an image receiving state (on state), first the first power switch is turned on, and then the sub power switch is turned on. Is required to be turned on by the remote control device to turn on the relay 3 and requires two operations. In addition, the user has two switches, a main power switch and a sub power switch, on the main body of the receiver, which may be confusing and the operation may be wrong.

Therefore, if a control circuit for controlling the relay to be turned on when the main power switch is turned on is provided, the receiver can be turned on by one operation. Therefore, the sub power switch can be deleted because it always turns on without using the remote control device. However, in this control circuit, if the main power switch is on, whether or not the second power switch is opened or closed by the operation from the remote control device, there is always a power failure and the power supply is restored. It will be turned on, which is not preferable for safety.

The present invention has been made in view of the above points, and there is provided an electric device including a remote control device capable of remotely controlling the on / off operation of the power supply of the main body of the device when the power supply is restored after the sub power switch is deleted. The purpose is to prevent it from being turned on.

Means for Solving the Problems In order to solve the above problems, the power switch control circuit of the present invention includes a first power switch which is connected to a power source and which can be manually operated, and the first power switch in parallel. A power failure determination circuit that detects a power failure of the connected power source, a second power switch that is connected between the first power switch and the load, and a receiver that receives the control signal transmitted from the remote control device. When the output from the receiving unit and the output from the power failure determination circuit are input and a signal to the effect that the connecting operation of the second power switch is performed is received by the receiving unit, the second power switch Is closed and the power is restored after the power failure is detected by the power failure determination circuit, the first power switch is closed, and the second power switch is closed before the power failure. hand Also comprises a control circuit for controlling the switch of the second power source so as not to be closed.

Action The power failure determination circuit having the above configuration determines whether the first power switch is on / off and the power failure, and the control circuit controls the second power switch to delete the sub power switch and after the power failure, The second power switch is prevented from being closed when the power is restored.

Embodiment FIG. 1 is a block diagram showing an embodiment of the power switch control circuit of the present invention. In FIG. 1, 1 is a power source voltage source, 2 is a first power source switch having one connection terminal connected to the power source voltage source 1, 3 is a second power source switch, and 4 is a first power source switch.
Is a power failure determination circuit that detects the voltage at the input end of the power switch and determines whether or not there is a power failure. Reference numeral 10 is a control circuit that can control the remote signal received by the receiving unit 8 from the remote control transmitter 7, and controls the second power switch, and 6 is a load that represents the circuits after the main power switch control circuit.

In addition, the control circuit controls to turn on the second power switch when the first power switch 2 is switched from off to on and the voltage at the point a is detected.

 Hereinafter, the operation will be described.

First, when the first power switch is operated from off to on (point (A) in FIG. 3), the control circuit 5 detects the voltage at the point a and determines that the first power switch is turned on. The second power switch is automatically operated from off to on to supply power to the load 6. Since it operates in this way, the conventional sub power switch is not required.

Further, when the input from the voltage source 1 is temporarily stopped (point in FIG. 3B) while the first power switch is on, and then restored (point in FIG. 3C), the power failure determination circuit 4 Detects a power failure, the control circuit 5 recognizes that there is a power failure by referring to the output from the power failure determination circuit, and does not turn on the second power switch even if the power is restored.

FIG. 2 shows a concrete circuit of the above-mentioned power failure judging circuit and control circuit, which comprises a relay as a second power switch, and a diode 301, capacitors 303, 305, resistors 302, 304, 306 and a transistor 307 as a power failure judging circuit 3. Circuit is used. Further, the control circuit 4 includes a microcomputer 401, a diode 402, a capacitor 403, resistors 404, 40.
5, 406, 408, and transistor 407.

 Hereinafter, the operation will be described.

First, when power is supplied from the voltage power supply 1,
The waveform of the output b of the power failure determination circuit remains GND regardless of whether the first power switch 2 is on or off because the transistor 307 is on. If a power failure occurs with the first power switch turned on, the capacitor 303,
The electric charge charged in 305 is discharged. After that, when the power is restored, the transistor 307 does not turn on until the capacitors 303 and 305 are charged (this delay time corresponds to the time T shown in FIG. 3), so the output b from the power failure determination circuit, that is, the point b. The output is as shown in FIG. On the other hand, the microcomputer 401 of the control circuit 4
Observes the waveforms at points a and b, and as shown in FIG. 3, the first power switch 2 turns from off to on (point (A) in FIG. 3), and the output at point a changes from low to high. However, if the output at point b does not go from low to high, it is determined that the first power switch 2 has been turned on, and the second power switch 3
Turn on the (relay). Further, as shown in FIG. 3, even when the second power switch 3 is in the on state at the time of power failure (point in FIG. 3 (B)), the power is restored (point in FIG. 3 (C)),
If the output at point a changes from low to high and the output at point b changes from low to high at the same time, it is determined that the power supply is restored after a power failure, and the second power switch 3 remains in the off state. .

As described above, according to the present invention, as described above, the sub-power switch can be eliminated, and the user can use a single power switch to remotely control the power supply of the device main body with an electric control device. It is possible to control the on / off state of the equipment, and to prevent the electric equipment from turning on when the power is restored after a power failure, which is practically effective.

[Brief description of drawings]

1 is a block diagram of a power switch control circuit according to an embodiment of the present invention, FIG. 2 is a block diagram of a power switch control circuit according to another embodiment, FIG. 3 is an output waveform diagram of a power failure determination circuit, and FIG. The figure is a block diagram of a conventional power switch control circuit. 1 ... Power supply voltage source, 2 ... First power switch, 3 ...
Second power switch, 4 ... A power failure determination circuit. 5 ...
… Control circuit, 6… Remote control transmitter, 6…
…load

Claims (1)

[Claims] 1. A first power switch which is provided on the main body of the apparatus so as to be manually operable and has one end connected to a power source; a power failure determining means for determining a power failure; and the first power switch and a load circuit. A second power switch that is connected and is closed in conjunction with the operation of the first power switch when the first power switch is closed in an energized state; and a receiving unit that receives a control signal from the remote control device. When the receiving unit receives a signal from the remote control device to connect the second power switch, the second power switch is closed and a power failure is detected by the power failure determination means. After the power supply is restored, the first power switch is closed, and even if the second power switch is closed before the power failure, the second power switch is not closed. Power switch control circuit having a Gosuru control circuit.