JPH085432Y2 - Signal converter - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a signal converter having a function of discriminating between disconnection of power supply and removal of a gas alarm.

[Conventional technology]

Conventionally, a signal converter as shown in FIG. 3 has been used. In FIG. 3, reference numeral 1 is a signal converter, which is supplied with power by connecting the power plug 2 to a commercial power supply. 3 is a signal input terminal, 4 is a signal output terminal, and 5 is a power outlet. A gas alarm 10 is supplied with power by inserting the power plug 11 into the power outlet 5 of the signal converter 1. An output terminal 12 generates a voltage signal.
The voltage signal is, for example, 6 V in the normal state, 12 V in the abnormal (gas leak) state, and 0 V in the case of disconnection or pulling out the power plug 11. Reference numeral 13 is a control circuit, which when the output signal from the signal converter 1 is received, a gas shutoff valve 14
Cut off.

[Problems to be solved by the device]

In the above configuration, when the power plug 11 is pulled out,
The gas alarm 10 loses its function, and the gas shutoff valve 14 does not operate even if a gas leak occurs. That is, there is a problem that gas is supplied even if a person who intends to commit suicide or the like pulls out the power plug 11. In addition, there is a system in which the gas shutoff valve 14 is shut off when the power plug 11 is pulled out, but the gas shutoff valve 14 operates even when the commercial power supply is cut off, and the gas shutoff valve 14 is activated each time.
There was a problem that 14 had to be restored.

[Means for solving the problem]

A signal converter according to the present invention comprises a signal input terminal (3) to which a voltage signal from a gas alarm device (10) is applied and a power outlet (5) for supplying power to the gas alarm device.
And a signal output terminal (4) for outputting a drive signal for operating the gas cutoff valve (14) when the voltage signal of the gas alarm device is a gas leak alarm signal, and a power source is supplied from a commercial power source. In the signal converter to be supplied, the voltage of the commercial power supply and the voltage of the voltage-applied signal, which detects that only the voltage-applied signal becomes 0 V, and generates the drive signal for the gas cutoff valve. Signal loss detection circuit (6)
It is provided with.

[Action]

In this invention, when only the voltage of the voltage signal is 0V among the voltage of the commercial power supply and the voltage of the voltage signal, the voltage signal loss detection circuit detects this and outputs the drive signal of the gas cutoff valve. generate.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention, in which the same reference numerals as those in FIG. 3 indicate the same parts, and 6 is a voltage loss signal detection circuit, which is a commercial power supply voltage Va and a gas alarm 10 When the power source voltage Va is present but the voltage signal Vb disappears, the gas shutoff valve 14
The drive signal Vc is generated.

 That is, the operating state is as shown in Table 1 below.

FIG. 2 is a circuit diagram showing a more concrete embodiment of the present invention.

In this figure, R _{1 to} R ₁₀ are resistors, C ₁ and C ₂ are capacitors, and ZD ₁
~ ZD ₄ is a Zener diode, D ₁ ~ D ₄ is a diode, P
C ₁ and PC ₂ are photo couplers, TM is a timer, Q ₁ and Q ₂ are transistors, and the same reference numerals as those in FIG. 1 indicate the same parts.

 Next, the operation will be described.

6V is output as a voltage signal Vb from the output terminal of the gas alarm device 10 during normal time without gas leakage. This voltage signal Vb is applied to the signal input terminal 3, but the transistor Q ₁ cannot be turned on, so the LED of the photocoupler PC ₁
Keeps lighting. As a result, the phototransistor PD of the photocoupler PC ₁ is maintained in the ON state, so the timer TM does not start. That is, there is no output at the output terminal T ₀ of the timer TM, the transistor Q ₂ remains in the OFF state, and therefore the photocoupler PC ₂ does not operate, so there is no output from the signal output terminal 4 to the control circuit 13. Therefore, the gas shutoff valve 14 is kept open and gas is supplied.

Next, when the commercial power supply fails, both the power supply voltage Va and the voltage signal Vb become 0. Therefore, the photocoupler PC ₂
Does not operate and the gas shutoff valve 14 does not operate in this case either.

Next, when the power supply voltage Va exists and only the voltage signal Vb becomes 0 to 0, the transistor Q ₁ turns off, and the current cannot flow to the LED of the photocoupler PC ₁ .
Since the LED of PC ₁ is turned off, the timer TM starts, outputs after a predetermined time, turns on the transistor Q ₂ , thereby actuating the photocoupler PC ₂ and actuating the control circuit 13 to turn on the gas cutoff valve 14. Close and stop gas supply.

Furthermore, if the power supply voltage Va is present and the voltage signal Vb is 12
When it becomes V, that is, when the gas leak alarm device 10 detects a gas leak of an alarm level, the transistors R _{1 to} R ₄ and ZD ₂ are set to turn on the transistor Q _1. Q ₁ turns on and the LED on the photocoupler PC ₁ goes off. Therefore, the gas cutoff valve 14 is operated and the gas supply is stopped in the same manner as when the voltage signal Vb becomes zero.

[Effect of device]

As explained above, this device has the voltage of the commercial power supply,
Of the voltage of the voltage signal, only the voltage signal is detected to be 0V, and a voltage signal loss detection circuit that generates a drive signal for the gas cutoff valve is provided. When the valve is pulled out, the gas cutoff valve operates and the gas supply is stopped, which is effective in preventing suicide and the like. In addition, since the gas cutoff valve does not operate during a power failure, gas can be used even during a power failure.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention,
FIG. 2 is a circuit diagram showing a more specific embodiment, and FIG.
FIG. 1 is a block diagram showing an example of the configuration of a conventional signal converter. In the figure, 1 is a signal converter, 2 is a power plug, 3 is a signal input terminal, 4 is a signal output terminal, 5 is a power outlet, 6 is a voltage loss signal detection circuit, 10 is a gas alarm device, and 11 is a power plug. , 12 is an output terminal, 13 is a control circuit, and 14 is a gas shutoff valve.

Claims (1)

[Scope of utility model registration request] 1. A signal input terminal (3) to which a voltage signal from a gas alarm device (10) is applied, a power outlet (5) for supplying power to the gas alarm device, and an existence of the gas alarm device. Gas shutoff valve when the voltage signal is a gas leak alarm signal (14)
A signal output terminal (4) for outputting a drive signal for activating, and a signal converter to which power is supplied from a commercial power source, in the voltage of the commercial power source and the voltage of the voltage signal A signal converter comprising a voltage signal disappearance detection circuit (6) for detecting that only the voltage signal has become 0 V and generating a drive signal for the gas cutoff valve.