JPH0476432A - Device for detecting abnormality of gas supply facility - Google Patents

Abstract

PURPOSE:To automatically determine whether gas leakage occurs or not, by measuring flow rates of gas passing through gas supply facilities upstream and downstream of a gas meter so as to determine that gas leakage occurs in the upstream gas supply facility if the measured flow rates are not equal to each other. CONSTITUTION:There are provided flow rate sensors 8, 9 for measuring flow rates of gas passing through parts upstream and downstream of a gas meter 4. A comparator 12 delivers a signal when a signal from the sensor 9 exceeds a certain level L such as 3 liters/hour. Further, a comparator 13 delivers a signal when a signal from the sensor 8 exceeds the level L. A gate circuit 14 transmits the output of the comparator 13 to a timer circuit 15 when the signal is delivered from the comparator 12. Accordingly, the signal from the sensor 8 can be transmitted to the circuit 15 only when the signal from the sensor 9 is blow the level L, but when it is above the level L, the circuit 15 is energized so that LEDs are turned on in an output means 11 in order to alarm an abnormality, and accordingly, the supply of gas is cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a gas supply equipment abnormality detection device for detecting gas leakage from LP gas supply equipment.

Conventional technology In recent years, in order to prevent explosions due to gas leaks and fires caused by forgetting to turn off gas appliances, gas meters have been installed to monitor gas leaks and the usage time of gas appliances, and gas appliances are being used for long periods of time. Gas cutoff devices are now being installed that determine that gas appliances have been forgotten to be turned off and shut off the gas supply, ensuring safety downstream from the gas meter. . On the other hand, regarding safety management upstream of the gas meter, that is, from the LP gas cylinder to the gas meter, conventionally a person went to the site once every two years to conduct a safety check.

An overview of such conventional safety management will be explained with reference to FIG.

FIG. 3 is a block diagram of a conventional safety check method for gas supply equipment. In FIG. 3, 1 is an LP gas cylinder, 2 is a main valve of the cylinder, 3 is a pressure regulator, 4 is a gas meter, 5 is a gas appliance, 6 is a pressure gauge, and 7 is a pen recorder.

The operation of the safety check means in the conventional gas supply equipment constructed as described above will be explained with reference to FIG. Once every two years, a person visits the site, connects a pressure gauge 6 in the middle of the gas pipe between the pressure regulator 3 and the gas meter 4, and measures the gas pressure inside the gas pipe with a pen recorder 7. In order to detect gas leakage from the gas supply equipment between the pressure regulator 3 and the gas meter 4, the built-in gas cutoff valve in the gas meter 4 is closed, and the main valve 2 to the bong is closed. If there is a gas leak, the gas pressure recorded on the pen recorder 7 will gradually decrease over time.

If the invention aims to solve the above-mentioned configuration, however, there is a problem in that it is necessary for a person to go to each site and install check equipment to check for gas leaks, which takes time and effort.

In view of the above problems, the present invention provides a gas supply equipment abnormality detection device that can automatically check for gas leakage from gas supply equipment.

Means for Solving the Problems In order to solve the above problems, the gas supply equipment abnormality detection device of the present invention includes a flow rate detection means for detecting the gas flow rate passing through the gas supply equipment upstream of the gas meter constituting the gas supply equipment. and a flow rate detection means for detecting the gas flow rate passing through the gas supply equipment on the downstream side of the gas meter, and a judgment for determining whether there is an abnormality in the gas supply equipment by inputting signals from the two flow rate detection means. and an output means operated by a signal from the determination means.

Operation The present invention uses the above-described configuration to automatically measure the gas flow rate passing through each of the gas supply equipment upstream and downstream from the gas meter, and if the respective flow rates are not equal, the gas supply equipment upstream from the gas meter is automatically measured. It can be determined that there is a gas leak from the equipment, and the need to manually check for gas leaks can be omitted.

EXAMPLE Hereinafter, a gas supply equipment abnormality detection device according to an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a gas supply equipment abnormality detection device in an embodiment of the present invention. In FIG. 1, 1 is an LP gas cylinder, 2 is a main valve of the cylinder, 3 is a pressure regulator, 4 is a gas meter, 5 is a gas appliance, and 8 is a flow rate detection means for detecting the gas flow rate passing upstream of the gas meter 4. be. A flow rate sensor, 9 is a flow rate sensor that is a flow rate detection means for detecting the gas flow rate passing downstream of the gas meter 4, 10 is a judgment device, 11 is an output means, 12 is a comparator, 13 is a comparator, 14 is a gate circuit, 15 is a timer circuit. Note that bronches showing the same functions as those in the conventional example shown in FIG. 3 are given the same numbers.

The operation of the gas supply equipment abnormality detection device, which is an embodiment of the present invention configured as described above, will be described below.

A signal from the flow rate sensor 9 is input to a comparator 12. Comparator 2 outputs a signal when the signal from the flow rate sensor 9 is at a certain level, for example, 3 liters/hour or less (note: the law stipulates that gas leaks of 3 liters/hour or more can be detected). It is set. The comparator 13 is set to output when the output of the flow rate sensor 8 is at a certain level, for example, 3 liters/hour or more. The gate circuit 14 transmits the output of the comparator 3 to the timer circuit 15 only when there is a signal from the comparator 12. Therefore, only when the signal from the pressure sensor 9 is below a certain level, for example 3 liters/hour, the pressure sensor 8
is transmitted to the timer circuit 15, and if the flow rate is at a certain level, for example 3 liters/hour or more, the timer circuit 1
5 works. In order to eliminate noise, the timer circuit 15 is configured to output a signal to the output means of the next stage only when the signal is present for a certain period of time or more. The output means 11 notified of the abnormality lights or blinks an LED to notify a person of the abnormality, or notifies a management center of an alarm using a telephone line or the like. Alternatively, a gas cutoff valve installed in the gas supply equipment is operated to stop the gas supply.

As described above, according to this embodiment, the gas flow rate detection means detects the gas flow rate passing through the gas supply equipment on the upstream side of the gas meter constituting the gas supply equipment, and the gas flow rate passing through the gas supply equipment on the downstream side of the gas meter. a flow rate detection means for detecting the gas flow rate; a determination means for inputting signals from the two flow rate detection means to determine whether there is an abnormality in the gas supply equipment; and an output means operated by the signal from the determination means. With this configuration, when the amount of gas fL flowing downstream from the gas meter 4 is almost zero, if the gas flow rate flowing upstream of the gas meter 4 is above a certain level, it is detected that there is a gas leak upstream from the gas meter 4, and the person This means that safety measures can be taken, such as notifying people and operating shutoff valves.

FIG. 2 is a block diagram of a gas supply equipment abnormality detection device according to another embodiment of the present invention. In Figure 2, 1 is L
P gas cylinder, 2 is the main valve of the cylinder, 3 is the pressure regulator, 4
is a gas meter, 5 is a gas appliance, 8 is a flow rate sensor that is a flow rate detection means for detecting the gas flow rate passing upstream of the gas meter 4, and 9 is a flow rate detection means for detecting the gas flow rate passing downstream of the gas meter 4. A certain flow rate sensor, 10 is a determination means, 11 is an output means, 16 is a differential amplifier, 17 is a comparator, and 15 is a timer circuit. Note that blocks having the same functions as those in the embodiment of FIG. 1 are given the same numbers.

The operation of the gas supply equipment abnormality detection device, which is an embodiment of the present invention configured as described above, will be described below.

In the differential amplifier 16, the signals from the flow rate sensor 8 and the flow rate sensor 9 are differentially amplified. Therefore, the difference between the gas flow rate flowing downstream of the gas meter 4 and the gas flow rate flowing upstream of the gas meter 4 is amplified. If there is a gas leak in the gas supply equipment upstream of the gas meter 4, the flow rate sensor 8
The output from the flow rate sensor 9 becomes larger than the output from the flow rate sensor 9, and the output from the differential amplifier 16 increases. and a certain level set by comparator 17, for example 3 liters/
When the time is exceeded, an output is generated in the comparator 17 and the timer circuit 15 is operated. In order to eliminate noise, the timer circuit 15 is configured to output a signal to the output means of the next stage only when the signal is present for a certain period of time or more. When the output means 11 is notified of the abnormality, it notifies a person of the abnormality by lighting or blinking an LED, or notifies a management center of an alarm using a telephone line or the like. Alternatively, a gas cutoff valve installed in the gas supply equipment is operated to stop the gas supply.

As described above, according to this embodiment, the determination means detects the signal from the pressure detection means for detecting the gas flow rate passing through the gas supply equipment downstream of the gas meter, and the signal passing through the gas supply equipment upstream of the gas meter. The gas meter 4 is configured to determine that there is an abnormality when the difference with the signal from the output detection means for detecting the gas flow rate exceeds a certain level.
Even if a gas appliance is used and the gas flow rate is downstream of the gas meter 4, the difference between the gas flow rate flowing upstream of the gas meter 4 and the gas flow rate flowing downstream of the gas make 4 can be determined. This means that safety can be ensured by accurately detecting gas leaks and notifying people or closing the gas cutoff valve.

Note that the gas supply equipment abnormality detection device of the present invention includes a flow rate sensor 9.
(All or part of the gas meter 4 may be built-in except for the flow rate sensor 8, or all or a part of the gas supply equipment abnormality detection device may be built in the pressure regulator 3.) It may be a separate unit, or a part of it, for example, the flow rate sensor 8, may be built into the pressure regulator 3, and the other part may be provided elsewhere.Also, the flow rate sensor 8 may be located downstream of the pressure regulator 3. Further, the flow rate sensor 9 may be built into the gas meter 4. Furthermore, the determination means 10 may be realized by software logic using a microcomputer.

Effects of the Invention As described above, the present invention includes a flow rate detection means for detecting a gas flow rate passing through a gas supply facility upstream of a gas meter constituting a gas supply facility, and a flow rate detection means for detecting a gas flow rate passing through a gas supply facility downstream of the gas meter. a flow rate detection means for detecting the gas flow rate;
Gas is supplied to the upstream side of the gas meter 4 by using the signals from the two flow rate detection means as human power, and the configuration includes a determination means for determining whether there is an abnormality in the gas supply equipment, and an output means operated by the signal from the determination means. It is possible to provide a gas supply equipment abnormality detection device that can detect gas leaks from equipment and take safety measures such as notifying people or operating a shutoff valve.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a gas supply equipment abnormality detection device in one embodiment of the present invention, Fig. 2 is a block diagram of a gas supply equipment abnormality detection device in another embodiment of the present invention, and Fig. 3 is a block diagram of a gas supply equipment abnormality detection device in another embodiment of the present invention. It is a conventional block diagram. 1...To LP gas cylinder, 3...Pressure regulator, 4...Gas meter, 5...Gas appliance, 6...Pressure gauge , 9...Flow rate sensor, 10...Determination means, 11...Output means, 15...Timer circuit, 16...
Differential amplifier.

Claims (3)

[Claims] (1) Flow rate detection means for detecting the gas flow rate passing through the gas supply equipment on the upstream side of the gas meter constituting the gas supply equipment; and flow rate detection means for detecting the gas flow rate passing through the gas supply equipment on the downstream side of the gas meter. gas supply equipment, comprising: a determination unit that receives signals from the two flow rate detection units as input and determines whether or not there is an abnormality in the gas supply equipment; and an output unit that operates based on the signals from the determination unit. Anomaly detection device. (2) The determination means detects the gas flow rate passing through the gas supply equipment on the downstream side of the gas meter, and the signal from the pressure detection means is below a certain level, and the gas flow rate passes through the gas supply equipment on the upstream side of the gas meter. The gas supply equipment abnormality detection device according to claim 1, wherein the gas supply equipment abnormality detection device is configured to determine that there is an abnormality when the signal from the pressure detection means for detecting the pressure exceeds a certain level. (3) The determination means detects the signal from the pressure detection means for detecting the gas flow rate passing through the gas supply equipment on the downstream side of the gas meter, and the pressure detection means for detecting the gas flow rate passing through the gas supply equipment on the upstream side of the gas meter. 2. The gas supply equipment abnormality detection device according to claim 1, wherein the gas supply equipment abnormality detection device is configured to determine that the gas supply equipment is abnormal when the difference between the signal and the signal from the gas supply equipment exceeds a certain level.