JPH05334584A - Gas security system - Google Patents

Abstract

(57) [Abstract] [Purpose] To realize a gas security system that can improve safety by using a gas meter and a gas leak alarm. [Composition] The gas meter is provided with a circuit for detecting a signal corresponding to the presence or absence of gas leak of the gas leak alarm device, and a signal sending circuit for passing a signal from the gas leak alarm device to the gas leak alarm device. -Monitor the gas leak alarm from the server side. This makes it possible to monitor the state of the gas leak alarm device from the gas meter side without increasing the number of signal lines connecting the indoor gas leak alarm device and the outdoor gas meter.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to gas security systems, and more particularly to a more secure and improved gas security system.

[0002]

2. Description of the Related Art Conventionally, as a gas security system, (a) a system for converting an inflow of gas into a rotary motion to detect an abnormal flow rate by a program and operating a shutoff valve; There was a gas meter with a shutoff valve and a gas leak alarm connected to it. FIG. 4 is a block diagram of a gas meter with a gas cutoff valve. In FIG. 4, 11 is a gas metering unit having a diaphragm (hereinafter, simply referred to as a metering unit), 12 is a transmitter that transmits a metering signal of the metering unit 11 to a control unit 14 via a detection unit 13 described later, and 13 is a transmitter. A detection unit that converts the operation of the transmission unit 12 into an electric signal to be transmitted to the control unit 14, 14 a control unit that controls the entire gas meter, 15 an external output unit thereof, and 16 a gas cutoff valve (hereinafter, It is called a shutoff valve). The general operation of the gas meter constructed in this way is as follows. When the gas flows in and enters the metering unit 11, the diaphragm delivers the gas while repeating the contracting motion, and at the same time, transmits the motion to the transmitting unit 12. In the transmission part 12, the above-mentioned motion is converted into rotational motion, and as shown in FIG. 5, the rotary plate 12A on which the magnet is installed is rotated. When the rotary plate 12A rotates, the lead switch 13A of the detection unit 13 is turned on and off to generate a pulse corresponding to the flow rate.

The control section 14 monitors the above-mentioned pulse as a flow rate signal, and makes judgment and control according to a predetermined program. FIG. 6 is a diagram showing an example of the program. A safe use time corresponding to the flow rate is set in advance, and when the safe use time is continuously exceeded, a judgment is made as "abnormal situation" and the shutoff valve 16 is closed. Also, in conjunction with the shutoff operation of the shutoff valve 16,
A signal is generated at the external output unit 15 to indicate that the shutoff valve 16 is closed. Apart from the control by the program as described above, a so-called gas leak detector or a gas leak alarm (hereinafter, represented by a gas leak alarm) is also widely used. FIG. 7: is a figure which shows the characteristic of the conventional gas leak alarm. When equipped with an external output, this external output indicates 0 V when the gas leak alarm is powered off, 6 V when the power is on and in operation, and 12 V when a gas leak is detected. Is configured. FIG. 8 is a block diagram of a gas security system showing another conventional example. Apart from the one shown in FIG. 4, as a gas security system, as shown in FIG. 8, there has been proposed a structure in which the gas leak alarm and the gas meter with a gas shutoff valve are combined.

In the gas security system of FIG. 8, the output of a conventionally used gas leak alarm is led to the gas meter with the gas cutoff valve. This system has the advantage that it functions even when you are away, but here the gas leak alarm still functions only as an alarm. By the way, even in the control by a program that presets the gas use flow rate and the use time corresponding thereto as described above, there are the following problems. For example, in FIG. 6 shown above, there is no problem in the case of an abnormally large flow rate at the left end of the graph, but there is the following problem when considering the minute flow rate region at the right end of the graph. That is, such a minute flow rate is expected to be due to a leak due to a minute crack in the piping, but some users leave the pilot fire of the bath on. Is indistinguishable. In the middle region of the graph, some gas combustion appliances have similar gas flow rates, which makes the determination even more difficult. For example, a stove and a stove have almost the same gas flow rate depending on the type, but
While the lobe may be used for 5 to 6 hours continuously, the stove is normally not considered for such a long time, and such a situation must be judged as abnormal. The same is true for baths and water heaters.

[0005]

The conventional program is
Despite the above-mentioned circumstances, there is a tendency that the time setting is set longer than necessary due to fear of malfunction. This is not preferable from the standpoint of ensuring safety. In particular, in the case of so-called city gas, the gas is lighter than air, so the diffusion tendency is strong, and the risk can be estimated by desk calculation, but L
In the case of PG (liquefied petroleum gas), since the gas is heavier than air, it may stay in part and reach the lower explosion limit immediately. Therefore, it is difficult to judge an abnormal situation only by the flow rate diagnosis as in the control by the above-mentioned program. As a solution to this, interlocking with the above-mentioned gas leak alarm is considered indispensable. on the other hand,
It is also inconvenient for the user to immediately close the gas cutoff valve if he feels a little dangerous because he is so enthusiastic about ensuring safety. The object of the present invention is made in view of the above circumstances, solves the above-mentioned problems in the conventional gas security system, and utilizes the gas meter and the gas leak alarm,
It is to provide a gas security system with higher safety.

[0006]

In order to achieve the above object, the gas security system of the present invention is a gas security system in which a gas meter with a gas shutoff valve and a gas leak alarm are connected by two wires. , Gas
Means for detecting a signal corresponding to the presence / absence of a gas leak of the gas leak alarm (1) in the controller (2 in FIG. 1) (detection unit 1 of 2
3), signal sending means (Tr ₁ , Tr ₂ , Tr ₃ , T of ₂ ) for passing a signal from the gas meter to the gas leak alarm (1).
r ₄ ) is provided to monitor the state of the gas leak alarm from the gas meter (2) side.

[0007]

According to the present invention, there is provided a gas security system comprising a gas meter with a gas shutoff valve and a gas leak alarm connected by two wires. and de switch LS _1, Gasume - - Li in which detection signal is operated thereby the coil 4A which is connected to a signal line that is output and the coil 5A connected to the signal line from the motor side, thereby re works - de A switch LS ₂ is provided. Further, in the gas meter with the gas cutoff valve,
A metering unit 11, a transmission unit 12, a detection unit 13, a control unit 14, an external output unit 15, and a shutoff valve 16 are provided. The control unit 14
The gas leak alarm 1 is checked at any time, and the control unit 14
When detects an abnormal situation, the shutoff valve 16 is closed.
In addition, the control unit 14 can perform control based on a check program of the gas usage flow rate and the usage time corresponding to the gas usage flow rate, or other control, for example, based on a signal from an earthquake detector. In addition, the control unit 14 can detect an abnormal situation based on various detection signals and notify the householder (user) of this when the shutoff valve 16 is closed. With this, a gas leak alarm provided in the room,
It is possible to monitor the state of the gas leak alarm device from the gas meter side without increasing the number of signal lines connecting to the gas meter provided outdoors. Further, since it is possible to provide the user with information such as a notice or interruption regarding the operation of the gas shutoff valve based on various conditions other than gas leakage from the gas meter side, it is possible to improve the reliability of the system. be able to.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a configuration diagram showing a main part of a gas security system showing an embodiment of the present invention. In this embodiment, the gas leak alarm 1 and the gas meter 2 with a gas shutoff valve (hereinafter, also simply referred to as "gas meter") are connected by signal lines 3A and 3B. In the gas leak alarm device 1, when a gas leak detection circuit (not shown) detects a gas leak, a coil 4A connected to a signal line from which a signal is output and the coil 4A is excited. A read switch LS ₁ composed of a contact 4B that closes the coil 5A, a coil 5A connected to the signal line from the gas meter 2 side, and a contact 5B that closes when the coil 5A is excited. A read switch LS ₂ is provided. Further, as shown in FIG. 4, the gas meter 2 is provided with a metering unit 11, a transmission unit 12, a detection unit 13, a control unit 14, an external output unit 15 and a shutoff valve 16, but in the present embodiment. In the example, as shown in FIG. 1, the above-mentioned external output unit 15 includes transistors Tr _{1 to} Tr ₄ and a resistor r.
_{1 to} r ₁₀ and the inverter 6.

The operation of the gas security system of the present embodiment constructed as described above is as follows. Normally, the output from the control unit 14 of the gas meter 2 is at H (High) level for both I and II. In this state, the transistors Tr ₁ , Tr ₂ and Tr ₃ are off, and only Tr ₄ is on. is doing. In this state, since the current loop is not formed, it is not possible to check the state of the gas leak alarm 1 which is the terminal. When checking the state of the gas leak alarm device 1, the output I of the control unit 14 is set to L
Set to (Low) level. As a result, the transistors Tr ₁ and Tr ₄ are turned on, so that a current can flow through the resistor r ₃ and the diode D ₁ .
Here, a state where the gas leak alarm 1 does not detect the gas leakage (hereinafter, referred to as "normal time") if, Li - for de switch LS ₁ is because it OFF, no current flows still, The potential at point A in the figure becomes H level.

Further, a state where the gas leak alarm 1 is detecting a gas leak (hereinafter, referred to as "abnormal") If, Li - will be de switch LS ₁ is turned ON, Le - flop Is formed and the potential at the point A becomes L level,
This can be detected on the gas meter 2 side. The control unit 14 can check the gas leak alarm 1 at any time by the method described above. By this check, when the control unit 14 detects an abnormal situation, control such as closing the shutoff valve 16 can be performed as described above. In addition to the gas leak check by the gas leak alarm 1 as described above, the control unit 14 performs control based on a check program of the gas usage flow rate and the corresponding usage time as described above, or further, For example, control based on a signal from the earthquake detector can be performed. Also,
The control unit 14 detects an abnormal situation based on the various detection signals as described above, and sets the output II to the L level in synchronization with the generation of the signal for closing the shutoff valve 16. This allows
Transistors Tr ₂ and Tr ₃ are turned on and diode D
_2, Li - current flows through-coil 5A and the resistance r ₄ of the switch LS _2. Thereby, the lead switch LS
_Since the contact 5B of ₂ is closed, if this signal is input to the buzzer of the gas leak alarm 1, the user can be notified of the occurrence of an abnormal situation. At this time, if the buzzer sounds differently from that at the time of detecting the gas leak by controlling the flow of the electric current, the content of the abnormality can be identified.

In the above embodiment, the signal is exchanged between the gas leak alarm device 1 and the gas meter 2 side via the lead switch LS ₁ or LS ₂ . This is because the AC100V normally used in the gas leak alarm 1 is not drawn into the gas meter 2 side, and it is possible to use a photo coupler other than the lead switch. FIG. 2 is a processing flowchart of the control unit showing another embodiment of the present invention. In the present embodiment, the control based on the conventional gas usage flow rate and corresponding usage time check program controls the immediate closing of the shut-off valve when an abnormal situation occurs. Instead of closing the shutoff valve immediately when the set time is reached instead of setting the use time corresponding to the gas usage flow rate to a shorter value than before, “If this state continues for a certain time, shut off It closes the valve ". That is, in the flow chart processing step 23, the constant flow rate state is detected by the detection unit 13, and in the processing step 25, the pulses are counted, and this reaches a predetermined number (that is, a predetermined time has elapsed). Is detected in processing step 26, and an advance notice signal (or advance notice message) prepared in advance is transmitted (processing step 27). In processing step 28, it is checked whether or not a predetermined time has passed after the advance notice signal is transmitted, and only when the predetermined time has passed, the shutoff valve 16 is closed (processing step 29) as in the conventional case. ..

FIG. 3 is a block diagram showing another embodiment of the control circuit shown in FIG. In FIG. 3, 1A indicates a gas leak alarm and 2A indicates a gas meter. Normally, the voltage V ₁₀ is supplied from the gas leak alarm device 1A to supply the gas meter 2A.
The photocoupler PC ₁ therein is driven to send a "normal" signal to the gas meter 2A side. However, in an abnormal situation where a gas leak is detected, the sending signal is switched to, for example, a continuous pulse signal. Notify the gas meter 2A side. on the other hand,
Gasume - from data 2A side when sending a signal notice or blocking such as described above, by supplying a current to the resistor r ₃ and drives the photocoupler PC _2, gas leak alarm 1
You can inform the A side. In this case, it is possible to identify by detecting the decrease in the potential at the point VA on the gas leak alarm device 1A side.

[0013]

As described above, according to the present invention,
Inside the gas meter, a means for detecting a signal corresponding to the presence or absence of gas leak of the gas leak alarm device, and a signal sending means for passing a signal from the gas leak alarm device to the gas leak alarm device are provided. Since the condition of the gas leak alarm from the
Without increasing the number of signal lines connecting the gas leak alarm device installed indoors and the gas meter installed outdoors,
It is possible to monitor the status of the gas leak alarm from the server side. Further, since it is possible to provide the user with information such as a notice or a shutoff from the gas meter side regarding the operation of the gas shutoff valve based on various conditions other than gas leakage, it is possible to further improve the reliability of the gas security system. Can be high.

[Brief description of drawings]

FIG. 1 is a configuration diagram of essential parts of a gas security system showing an embodiment of the present invention.

FIG. 2 is a processing flowchart of a control unit showing another embodiment of the present invention.
It's a chart.

FIG. 3 is a circuit configuration diagram showing another embodiment of the control circuit shown in FIG.

FIG. 4 is a block diagram of a conventional gas meter with a gas cutoff valve.

5 is a configuration diagram showing details of a weighing unit in FIG.

FIG. 6 is a diagram showing an example of a program for presetting a gas usage flow rate and a usage time corresponding thereto.

FIG. 7 is a diagram showing characteristics of a conventional gas leak alarm device.

FIG. 8 is a block diagram of a conventional gas security system.

[Explanation of symbols]

1,1A gas leak alarm 2,2A with the gas shutoff valve Gasume - motor 3A, 3B signal line 11 measuring unit 12 transmission unit 13 detecting unit 14 control unit 15 external output unit 16 shutoff valve D _1, D ₂ diode - de Tr _{1 to} Tr ₅ transistor r _{1 to} r ₁₇ resistance LS ₁ and LS ₂ lead switch PC ₁ and PC ₂ photocoupler

Claims (1)

[Claims] 1. A gas security system in which a gas meter with a gas shutoff valve and a gas leak alarm are connected by two wires, and whether or not there is a gas leak in the gas leak alarm in the gas meter. Means for detecting a signal to
By providing a signal sending means for passing a signal from the gas meter to the gas leak alarm, from the gas meter side,
A gas security system for monitoring the condition of the gas leak alarm.