JPH0241403Y2 - - Google Patents

Description

[Detailed explanation of the invention] In this invention, the voltage signal from the gas alarm
This invention relates to a gas cutoff valve interlocking device that automatically suppresses current consumption within a predetermined range when the value becomes larger than the normal value due to the occurrence of gas leakage or the like.

First, the outline of the gas cutoff valve interlocking device will be explained with reference to FIG. In Fig. 1, A is a gas alarm, which normally outputs a 6V voltage signal, and when a gas leak is detected, it outputs a 12V voltage signal. Also, when the wire is disconnected, it becomes 0V. B is a gas cutoff valve interlocking device which is the subject of this invention, and C is a gas cutoff valve. The gas cutoff valve interlocking device B normally receives a 6V voltage signal, that is, a normal signal, from the gas alarm A, and uses this as a power source to operate various internal parts, and receives a 12V voltage signal from the gas alarm A, That is, when an abnormal signal is received, it is distinguished from a normal signal, and the gas cutoff valve C is operated to cut off the gas supply. D is a centralized monitoring system, and the status of the gas alarm A is constantly transmitted from the gas cutoff valve interlocking device B.

In the conventional gas cutoff valve interlocking device B, when the voltage signal from the gas alarm A changes from 6V to 12V, the current consumption increases, which may cause problems.

This invention was developed in consideration of the above points, and is designed to automatically suppress current consumption when the voltage signal increases from a normal value. This idea will be explained below.

First, the entire gas cutoff valve interlocking device to which this invention is applied will be explained, and then the details of the main parts of this invention will be explained.

FIG. 2 is a block diagram of a gas cutoff valve interlocking device to which this invention is applied. In this figure, 1 is a surge reverse connection prevention circuit, which is composed of a surge absorber and a capacitor, and is used to protect against surge voltages generated in signal lines, +. – protects the repeater when reversely connected. 2 is a current consumption limiting circuit, which is the main part of this invention, and in order to reduce current consumption, it limits the current when the input reaches 12V (when an alarm state occurs).
3 is a 10V.20V booster circuit, the input voltage is 5V to 6V, the release pulse is approximately 20V, and the output voltage is 5.5V to
This is to increase the voltage since 7.5V is required. 4 is a return pulse generation circuit, which charges a 2200μF capacitor because an instantaneous voltage of about 20V is required to change the gas cutoff valve C from "closed" to "opened".
5 is a backup circuit, and even if the input voltage of the repeater becomes 0V due to a problem with gas alarm A, etc., the 5
A capacitor with a large capacity is charged in order to keep the gas cutoff valve C "open" for a minute. 6 is an alarm detection circuit that detects whether the input signal has reached the alarm level. 7 is a trouble detection circuit that detects whether the input signal has reached the trouble level (0V). 8 is a standby detection circuit,
The electrical energy required to detect whether the capacitor of the return pulse generation circuit 4 has been charged to a specified voltage, and to maintain the state of the gas cutoff valve C that has been opened by generating a return pulse. A signal is sent to a return pulse switch circuit 11, which will be described later. A one-minute timer 9 determines whether the alarm level (12V) has been maintained for one minute and sends a signal to the output voltage control circuit 13, which will be described later. 10 is a 5 minute timer,
It becomes a trouble level (0V), and it is determined whether this state continues for 5 minutes, and a signal is sent to the output voltage control circuit 13. A return pulse switch circuit 11 discharges the capacitor charged by the return pulse generation circuit 4 in a state confirmed by the standby detection circuit 8, etc., and generates a return pulse. 12 is an alarm trouble recovery detection circuit that judges whether the alarm or trouble continues for a predetermined time or longer and outputs a cutoff signal (0V), and if the cutoff signal is output, after the alarm or trouble is canceled,
Outputs a signal to generate a return pulse. 13 is an output voltage control circuit that outputs to gas cutoff valve C.
Creates 0V, 6V. and 19V signals, and outputs a signal corresponding to each state depending on the state. In other words, it is 0V after 1 minute when there is an alarm, 0V after 5 minutes when there is a problem, 6V when it is normal, and 6V when it is restored.
Generates a 19V pulse voltage. Reference numeral 14 denotes a manual closing circuit which generates a signal to immediately shut off the circuit by means of a manual switch. Reference numeral 15 denotes a current limiting circuit which limits the current of the centralized monitoring output so that the repeater operates even if the centralized monitoring output is shorted on the signal line.

FIG. 3 is a circuit diagram showing details of the current consumption limiting circuit 2, which is the main part of this invention. In FIG. 3, B' is the main body of the device, and 2 is a current consumption limiting circuit. The current consumption limiting circuit 2 has the following configuration. That is, _R5 is a resistor inserted in series between the input terminal 2A and the device body B',
Limits the current consumption of the device body B'. Q ₁ , Q ₂ , and Q ₃ are transistors, and R ₁ to R ₄ are resistors, and these constitute a switching circuit.

The configuration of the switching circuit will be further explained. A resistor R ₁ .R ₂ is connected in series between the input terminals 2A, 2B, the connection point of which is connected to the pace of the transistor Q ₁ , and the collector of the transistor Q ₁ is connected to the resistor R ₃
The emitter is connected to the input terminal 2A through the input terminal 2A, and the emitter is connected to the input terminal 2B. The base of transistor Q ₂ is connected to the collector of transistor Q ₁ ,
Its emitter is connected to input terminal 2B, and its collector is connected to the base of transistor _Q3 via resistor _R4 . The emitter and collector of transistor Q ₃ are each connected across resistor R ₅ .

Next, the operation will be explained.

The voltage signal from gas alarm A (Fig. 1)
0V.6V.12V, which is applied to input terminals 2A and 2B. The values of resistors R ₁ and R ₂ are determined so that when the voltage signal is 6V, the transistor Q ₁ is inactive, and when the voltage signal is 12V, it is activated.

Now, when the voltage signal is 6V, transistor Q ₁ is off, so transistor Q ₂ operates with the bias current from resistor R ₃ , and current flows between the emitter and base of transistor Q ₃ , so transistor Q ₃ is in operation, resistor R ₅ is shorted by transistor Q ₃ . Therefore,
A voltage signal of 6V is directly applied to the device body B'.

On the other hand, when the voltage signal becomes 12V, transistor Q ₁ is turned on and transistor Q ₂ is turned off. Transistor Q ₃ is turned off, and resistor Rs is connected to the device body B′.
A voltage signal of 12V is applied through the circuit, which limits the current consumption and supplies approximately the same current as when using 6V.

As explained in detail above, this invention is a gas cutoff valve interlocking device that uses a voltage signal as a power source.
A resistor that limits current consumption and a switching circuit connected in parallel to this resistor are provided, and this switching circuit is opened when the voltage signal becomes large and closed when the voltage signal is small. This has the advantage that a large voltage is not directly applied to the main body of the device, so that the internal parts can be sufficiently protected.

[Brief explanation of the drawing]

Fig. 1 is a block diagram for explaining the outline of the gas cutoff valve interlocking device, Fig. 2 is a block diagram of the gas cutoff valve interlocking device to which this invention is applied, and Fig. 3 is the current consumption, which is the main part of this invention. FIG. 2 is a circuit diagram showing details of a limiting circuit. In the figure, 2 is a consumption current limiting circuit, A is a gas alarm, B is a gas cutoff valve interlocking device, C is a gas cutoff valve,
D is the central monitoring system, R ₁ ~ R ₄ .Rs is the resistor, Q ₁
~ _Q3 is a transistor.

Claims (1)

[Scope of utility model registration request] It receives at least two types of voltage signals, large and small, from the gas alarm, and uses these voltage signals as power to open the gas cutoff valve. Closed. In the gas cutoff valve interlocking device that controls the return, there is a resistor that limits the current consumption, and a resistor that is connected in parallel with the resistor so that the input voltage is
1. A gas cutoff valve interlocking device comprising a switching circuit that opens when a higher voltage signal among the different voltage signals is reached.