JPH0551960B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an interlocking device for a gas cutoff device and a gas leak alarm device.

Configuration of a conventional example and its problems FIG. 1 shows a conventional gas cutoff alarm device. 1st
In the figure, 1 is a gas cutoff device which closes a cutoff valve 3 in response to a signal from a control unit 2 to cut off a gas passage 4. 5 is a gas meter to which a flow rate sensor 6 is attached. Reference numeral 7 denotes a gas leak alarm device connected to the gas cutoff device 1 via a signal line 8, which controls a signal from a gas sensor 9 and sends the signal to the signal line 8 via a photocoupler 10 in the event of a gas leak. A control section 11 is provided.

The operation of the gas cutoff alarm device configured as described above will be explained below.

The gas cutoff device 1 receives a signal from the gas leak alarm device 7 via a signal line 8 and shuts off the cutoff valve 3 when a gas leak occurs. It also has a function that receives the gas flow rate signal from the flow rate sensor 6 and drives the shutoff valve 3 if there is an abnormality (large flow rate) in the gas flow rate, or if the flow rate signal from the flow rate sensor 6 continues for an abnormal time. It has a function of driving the shutoff valve 3, etc.

However, the above conventional gas cutoff alarm device
Because only one-way communication is possible, when the cutoff valve 3 is in a situation where it should be cut off, for example, the battery in the control unit 2 has deteriorated and there is no capacity to operate the cutoff valve 3, or the cutoff valve 3 itself has malfunctioned. In this case, the gas cutoff device 1 detects the actual opening/closing of the cutoff valve 3, which must ensure sufficient safety, without the gas passage 4 being cut off even though the cutoff valve 3 is being driven. It had the disadvantage that it did not.

Purpose of the Invention The present invention has been made in view of the above-mentioned drawbacks of the conventional art. If the system is not shut off, the system notifies people of the abnormality through the gas leak alarm system, improving the reliability of the gas shutoff system and increasing the safety of the system. The purpose of the present invention is to provide a gas cutoff alarm device that makes it possible to

Structure of the Invention In order to achieve the above object, the present invention includes a gas cutoff device and a gas leak alarm device having a first communication means capable of communicating with the gas cutoff device, and the gas cutoff device has a gas cutoff valve and a flow rate. When the sensor, the second communication means, and the gas leak alarm device detect an abnormality, the first and second communication means shut off the gas cutoff valve, and the state of the gas cutoff device is controlled by the first and second communication means. The first communication means has two photocouplers, one on the emitter side of the light receiving element of the first photocoupler and the other on the emitter side of the light receiving element of the first photocoupler. The anode side of the light emitting element of the photocoupler is connected, the collector side of the light receiving element of the first photocoupler and the cathode side of the light emitting element of the second photocoupler are connected, and the light receiving element of the first photocoupler of the first communication means is connected to the anode side of the light emitting element of the first photocoupler. This gas cutoff alarm device communicates between the collector and the anode of the light emitting element of the second photocoupler and the second communication means via a pair (two) of signal lines.

With this configuration, it is possible to deal with abnormal situations such as a gas leak or when the cutoff valve is not actually cut off when it should be cut off, and the reliability and safety of the gas cutoff device can be improved.

DESCRIPTION OF EMBODIMENTS A gas cutoff alarm device according to an embodiment of the present invention will be described below based on the drawings.

In FIG. 2, the same members as in FIG. 1 are given the same numbers. Reference numeral 12 denotes a control section having other control functions as shown below in addition to the conventional functions. 13 is a transmitting/receiving device that switches the direction of a signal as a second communication means, and includes a NOR gate 14, transistors 15, 16, 17 for inverting the output, and a resistor 1.
It consists of numbers 8 to 23. 24 is the shutoff device 1'
A photocoupler that transmits a signal from the gas leakage alarm device 7' to the gas leak alarm device 7', and together with the photocoupler 10 constitutes a first communication means. 25 is a diode that protects the photocoupler 10 when a reverse voltage is applied. Reference numeral 26 denotes a control section of a gas leak alarm device 7' that includes a buzzer 27 as a notification device and a gas sensor 9.

The operation of the gas cutoff alarm device configured as described above will be explained below.

Normally, the control unit 12 is in a state where it receives a signal from the gas leak alarm device 7', that is, a signal indicating whether there is a gas leak, and keeps the control signal from the O terminal in the LO state. Since the control signal from the O terminal is LO, the transistor 15 is turned off and the A point becomes Hi. Further, the transistor 16 is off, the transistor 17 is on, and the B point is at LO. If there is a gas leak at this time, the control section 26 of the gas leak alarm device 7' turns on the photocoupler 10. Point A becomes LO via signal line 8, and this signal is passed through NOR gate 14.
The control unit 12 of the gas cutoff device 1' cuts off the cutoff valve 3 and the gas passage 4 by taking in the Hi signal from the i terminal. For example, if the shutoff valve 3 is
If the gas cutoff device 1' is driving the cutoff valve 3 but the cutoff valve 3 does not operate for some reason in a situation where it should be cut off, the gas passage 4 will not be cut off and the gas will continue to flow. This is the flow rate sensor 6
The gas flow rate signal is detected and sent to the control unit 12 as a gas flow rate signal, and it is determined that the cutoff valve 3 is not actually cut off, and the control signal from the O terminal is set to Hi.
Then, the control unit 12 no longer accepts the signal from the gas leak alarm device 7' due to the NOR gate 14.
Point B of transistors 16 and 17 becomes Hi, and point A of transistor 15 becomes OL. Then, the photocoupler 24 is turned on via the signal line 8, and the control section 26 of the gas leak alarm device 7' sounds the buzzer 27 to issue an alarm.

As described above, according to this embodiment, not only can a quick response be taken when the shutoff valve 3 shuts off, but also the best feature for the gas shutoff device 1' is that the shutoff valve 3 does not shut off when it should have shut off. By sounding the buzzer 27, the general public can be informed of a dangerous situation and can be quickly dealt with, thereby preventing major accidents such as explosions. In addition, since only two signal lines (one pair) are required to transmit signals from the gas cutoff device 1' to the gas leak alarm device 7', wiring effort during installation can be reduced and mistakes such as malfunctions caused by the wiring can be prevented. can do. In addition, the original signal line can be used even when replacing, and installation is easy.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

(b) It is possible to notify an emergency situation in which the shutoff valve of the gas cutoff device does not operate for some reason when it should be shut off, making it possible to respond quickly and improving the reliability of the gas cutoff device. can do.

(b) The gas cutoff device and the gas leak alarm device are equipped with two first and second photo couplers in the first communication means of the gas leak alarm device, and the emitter of the light receiving element of the first photo coupler and the second photo coupler are connected to each other. The anode of the light emitting element is connected, the collector of the light receiving element of the first photocoupler and the cathode of the light emitting element of the second photocoupler are connected, and the second communication means of the gas cutoff device and the second communication means of the first communication means are connected.
Because two-way signals are exchanged by connecting a pair of signal wires wired between each photocoupler, two signal wires are sufficient, which reduces the effort required to wire the signal wires during installation. Electrical insulation between the two devices can also be easily and reliably achieved, increasing reliability.

[Brief explanation of the drawing]

FIG. 1 is a control circuit diagram of a conventional gas cut-off alarm device, and FIG. 2 is a control circuit diagram of a gas cut-off alarm device according to an embodiment of the present invention. 1'... Gas cutoff device, 10, 24... Photo coupler (first communication means), 7'... Gas leak alarm device, 3... Gas cutoff valve, 6... Flow rate sensor, 1
3... Transmitting/receiving device (second communication means), 12...
Control unit, 8...communication line.

Claims (1)

[Claims] 1 comprising a gas cutoff device and a gas leak alarm device having a first communication means capable of communicating with the gas cutoff device, the gas cutoff device including a gas cutoff valve, a flow rate sensor, a second communication means, and the gas leakage alarm device. When the device detects an abnormality, the gas cutoff valve is shut off by the first and second communication means, and the state of the gas cutoff device is notified to the gas leak alarm device by the first and second communication means. The first communication means has two photocouplers, connects the emitter side of the light receiving element of the first photocoupler and the anode side of the light emitting element of the second photocoupler, and The collector side of the light receiving element of the first photocoupler and the cathode side of the light emitting element of the second photocoupler are connected, and the collector side of the light receiving element of the first photocoupler of the first communication means and the anode of the light emitting element of the second photocoupler are connected to the anode side of the light emitting element of the second photocoupler. A gas cutoff alarm device that communicates between means via a pair (two) signal lines.