JPH0843247A - Gas leakage monitoring device - Google Patents

Abstract

PURPOSE:To provide a gas leakage monitoring device which can surely detect gas leakage in its early stages and can control the flow of a gas based on the flow rate of the gas. CONSTITUTION:The gas leakage monitoring device 11 is provided with a flowmeter 33 which detects the flow rate of a gas from a gas cylinder 21, a branch pipe 35 which branches the flow of the gas to a pipeline 37 for measurement and another pipeline 36 for by-pass, a by-pass valve 34 which breaks the flow of the gas along the pipeline 36, a by-pass valve controlling program 18 for controlling the opening/closing of the valve 34, and gas meter 22 for storing section which detects the consumed amount of the gas. The device 11 is also provided with a sampling program 15 for sampling and calculating the gas consumption indicated by the meter 22 and that indicated by the gas meter 23a of each house during a prescribed period of time at every prescribed period of time when the valve 4 is closed and a gas leakage judging program 16 for judging the presence of gas leakage when the difference between the sum of gas consumption indicated by the gas meters 23a and the gas consumption indicated by the gas meter 22 becomes larger than a prescribed value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas supply system in which gas cylinders are centrally stored to supply fuel gas such as propane gas to each unit of an apartment house, and a gas supply pipe is connected to each unit from the cylinder. The present invention relates to a gas leak monitoring device used in a system.

[0002]

2. Description of the Related Art Conventionally, in order to supply propane gas or the like to each house of an apartment house, a cylinder house or the like for centrally storing gas cylinders has been installed. Here, a gas leakage monitoring device is used to detect a gas leakage when a gas leakage occurs in a piping system connected from a cylinder house to each house. As a gas leak monitoring device, for example,
In the pressure detection type gas leak monitoring device, after closing the main valve of the gas in each household, keeping the gas cylinder plug in the cylinder house open, filling the gas pipe between the gas cylinder and each household with gas of a predetermined pressure, Close the gas cylinder stopper. Then, the gas pressure in the gas pipe between the gas cylinder and each household is measured over a predetermined period of time, and it is checked whether or not there is a drop in the gas pressure. It is determined that a gas leak has occurred with the household.

Further, in a flow detection type leak monitoring device according to a second conventional example, a predetermined set time, for example, one hour at midnight, is determined, and it is detected whether or not the output signal of the gas meter of the cylinder house is generated at the set time. If there is an output signal, the set time is integrated, and when the integrated time reaches a predetermined gas leak estimation reference time, for example, 30 days, it is determined that a gas leak has occurred. That is, for example, a household using gas should not use much gas in a time zone such as midnight and, for example, 3 hours in a midnight time zone.
This is because it is unlikely to use gas even for 0 days, and it is determined that there is a high risk of gas leakage.

[0004]

However, the conventional gas leak monitoring device has the following problems. (1) In the pressure detection type leak monitoring device, it takes a long time to detect a gas leak because it takes a long time for the gas pressure to drop by a predetermined amount when the gas leak is small. Further, when detecting a gas leak, it is necessary to keep the main gas valve of each household closed, and the gas cannot be used in each household, which is inconvenient and not practical. In addition, the gas pressure may fluctuate due to a temperature change in the vicinity of the gas pipe, and even if there is a slight gas pressure drop, it is not possible to determine whether the gas pressure is due to a gas leak or a temperature change. .

(2) The flow rate detection type leak monitoring device has a problem that the gas leakage cannot be detected early because the estimated reference time is required to detect the gas leakage. In addition, in a multi-family house, there is a problem that the gas usage is various, and even if there is no gas leak, or if different households use the gas at midnight, the gas leak is detected.

On the other hand, in the supply of fuel gas in a large-scale apartment house, if a gas meter for measuring and storing all the gas consumption used in the storage unit is to be installed, a large and expensive gas meter must be installed. No. To avoid this, install a bypass flow path and a bypass valve for the flow path of the storage unit gas meter that measures gas consumption, and use the bypass flow path when the gas usage in each house is large. It is possible. However, when the bypass flow path is used, there is a problem that the sum of the gas consumption of the door-to-door gas meters and the gas consumption of the storage gas meter are different.

The present invention has been made in order to solve the above-mentioned problems, and when a gas leak occurs in a piping system that supplies gas from a gas cylinder to each house of a large-scale apartment house, it can be performed quickly and reliably. Can detect gas leaks,
Still another object of the present invention is to provide a gas leakage monitoring device that can control the flow of gas by the flow rate of gas.

[0008]

In order to solve the above-mentioned problems, a gas leakage monitoring apparatus of the present invention is a gas storage unit for storing fuel gas to be supplied to an apartment house, and a storage unit for storing the fuel gas. A piping system for supplying fuel gas to each house,
A gas leak monitoring device for detecting gas leak in a gas supply system having a door-to-door gas meter for detecting fuel gas consumption in each house, wherein the fuel gas is disposed between a gas storage unit and a piping system. A flow meter for detecting the flow rate of
A branch pipe downstream of the flow meter that branches the fuel gas flow into a measurement pipe and a bypass pipe, a bypass valve on the bypass pipe that blocks the fuel gas flow, and the flow meter were measured. Bypass valve control means for controlling the opening and closing of the bypass valve according to the gas flow rate, a storage unit gas meter for detecting the fuel gas consumption of the gas storage unit on the measuring pipe, and when the bypass valve is shut off, Every predetermined time, the gas consumption of the storage gas meter in the predetermined time, the sampling means for sampling and calculating the gas consumption of the door-to-door gas meter, the sum of the gas consumption of the door-to-door gas meter and the gas consumption of the storage gas meter And a gas leakage determining means for determining that the gas is leaking when and are different from each other by a predetermined value or more.

Further, the gas leakage monitoring apparatus of the present invention is characterized in that, in the above apparatus, when the gas leakage judging means judges that there is a gas leakage, a gas leakage alarm is displayed on the storage unit gas meter. Further, the gas leakage monitoring device of the present invention, in the above device, has a communication means connected to the gas supply central control device by a telephone line, and when the gas leakage determination means determines that there is a gas leakage, the communication means uses the communication means. It is characterized by transmitting a gas leakage warning to the gas supply central control unit.

[0010] In the gas leak monitoring device of the present invention, in the above device, the door-to-door gas meter and the storage gas meter have communication means connected to the gas supply central control device via a telephone line, and the gas supply central control device has a gas supply central control device. It is characterized by having leak judgment means. Further, the gas leak monitoring device of the present invention is characterized in that, in the above device, the gas leak judging device has shut-off means for shutting off gas supply when judging that there is a gas leak of a predetermined amount or more. .

[0011]

The gas storage unit of the gas supply system to be monitored by the gas leakage monitoring device of the present invention having the above-described configuration is:
Stores fuel gas for supply to apartments. Also,
The piping system supplies fuel gas from the storage unit to each unit of the apartment house. Further, the door-to-door gas meter detects the amount of fuel gas consumed in each house. A flow meter disposed between the gas storage unit and the piping system detects a flow rate of the fuel gas. Further, the branch pipe branches the flow of the fuel gas into a measurement pipe and a bypass pipe. The bypass valve blocks the flow of the fuel gas flowing through the bypass pipe. The bypass valve control means controls the opening and closing of the bypass valve according to the gas flow rate measured by the flow meter. Further, the storage unit gas meter of the gas leakage monitoring device is arranged on the measuring pipe and detects the fuel gas consumption of the gas storage unit. Further, the sampling means performs sampling calculation of the gas consumption amount of the storage unit gas meter and the gas consumption amount of the door-to-door gas meter for each predetermined time period when the bypass valve is shut off. The gas leak determining means determines that gas is leaking when the sum of the gas consumption of the door-to-door gas meters and the gas consumption of the storage unit gas meter differ by a predetermined value or more.

The gas leak judging means of the gas leak monitoring device displays a gas leak alarm on the gas meter of the storage unit when judging that there is gas leak. Further, when it is determined that there is a gas leak, the gas leakage determination means transmits a gas leakage alarm to the gas supply central control device by the communication means connected to the gas supply central control device by a telephone line. In addition, the door-to-door gas meter and the storage unit gas meter are connected via a telephone line by a communication means connected to the gas supply central controller.
The detected value is transmitted to the gas supply central control device, and the gas leakage determination means of the gas supply central control device determines whether the sum of the gas consumption of the door-to-door gas meters and the gas consumption of the storage gas meter are different from each other by a predetermined value or more. Is determined to be leaking. Further, when the gas leak determination means determines that there is a gas leak of a predetermined amount or more, the gas supply is cut off by the cutoff means.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A gas leakage monitoring apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a first embodiment. A plurality of gas cylinders 21 for supplying gas to the gas consumption facility installation locations a to n of each apartment house such as an apartment or an apartment are stored in a cylinder house 27. A gas pipe 31 from the gas cylinder 21 is connected to a flow meter 33. A branch pipe 35 that branches the flow of the fuel gas into a measurement pipe 37 and a bypass pipe 36 is connected to the flow meter 33. Measurement piping 3
The emergency shutoff valve 32 is attached to the pipeline of 7, and the bypass valve 34 is attached to the pipeline of the bypass piping 36. The storage section gas meter 22 and the bypass valve 34 are connected to the gas main pipe 24, and the gas meters 23a to 23
23n includes gas main pipes 24 to gas branch pipes 26a to 26n.
Connected by.

Next, the control system will be described. The gas leak monitoring device 11 is installed in the cylinder house 27. The gas leak monitoring device 11 includes a CPU 1
2, a RAM 13 for temporarily storing data and the like, a ROM 14 for storing a control program and the like, and a signal transmission device 17 connected to a gas supply central control device 29 of a gas supplier via a telephone line 28. I have. Also, R
The OM 14 stores a sampling program 15, a gas leak determination program 16, and a bypass valve control program 18. The gas leak monitoring device 11 is connected to the storage gas meter 22 and the door-to-door gas meters 23a to 23n. Further, the control wiring 31 is connected to the gas leakage monitoring device 11 from the flow meter 33, the bypass valve 34, and the emergency shutoff valve 32. A gas leak indicator light 30 is attached to the storage gas meter 22.

Next, the operation of the gas supply system having the above structure will be described. First, the operation of the bypass valve is shown in Fig. 3.
It will be described based on the flowchart shown in FIG. First, when the gas flow rate Q measured by the flow meter 33 exceeds or is equal to the preset flow rate K (S11, Y
ES), the bypass valve 34 is opened (S12), and gas flows to the gas main pipe 24 via the bypass pipe 36. This is because the storage unit gas meter 22 is downsized and the cost is reduced, and therefore the flow rate of the gas that can be supplied to the storage unit gas meter 22 is small. On the other hand, when the gas flow rate Q does not exceed the preset flow rate K ( In (S11, NO), the bypass valve 34 is closed (S13), and all the gas is supplied to the gas main pipe 24 through the measuring pipe 37 and the storage gas meter 22.

Next, the operation of the gas leakage monitoring device 11 having the above configuration will be described with reference to the flowchart shown in FIG. First, when the bypass valve 34 is closed (S0,
(YES) reads the detected values of the storage gas meter 22 and the door-to-door gas meters 23a to 23n at predetermined time intervals (S1, YES) and stores them in the RAM 13 (S2). Here, when the bypass valve 34 is closed, the gas does not flow to the bypass pipe 36 at all, but flows to the measurement pipe 37 at all, so the sum of the gas consumption measured by the individual gas meters 23a to 23n and the storage unit. The gas consumption of the gas meter 22 should match. On the other hand, when the bypass valve 34 is not closed (S0, NO), the process does not proceed to S1. The reason is that when the bypass valve 34 is not closed, the sum of the gas consumptions measured by the door-to-door gas meters 23a to 23n does not match the gas consumption of the storage gas meter 22.

In this embodiment, the predetermined time is set to 1 hour. This time may be longer, about 24 hours. Further, it is possible to change the predetermined time by the sampling program 15 according to the gas flow rate used. By changing the predetermined time, it is possible to efficiently monitor gas leakage. Next, regarding the door-to-door gas meters 23a to 23n, the current detection value and RA
The difference from the previous detection value already stored in M13 is calculated, and is stored in RAM 13 as usage S. Next, regarding the storage unit gas meter 22, the current detection value and the RAM 13
The difference from the previously detected value that has already been stored is calculated and stored in the RAM 13 as the usage amount M.

Next, the difference between the usage amount S and the usage amount M is calculated, and if the value is equal to or larger than the predetermined value N, the individual gas meters 23a-2a of the storage gas meter 22 are calculated.
It is determined that a gas leak has occurred in the gas main pipe 24 or the gas branch pipes 26a to 26n, which is a piping system connecting 3n, and a gas leak alarm is output to the gas supply central control device 29 (S6). The gas leak indicator light 30 is turned on.
Furthermore, when the amount of leaking gas is equal to or exceeds the predetermined amount L (S8, YES), the gas supply is shut off by the emergency shutoff valve 32 because there is concern about an accident due to the leaking gas (S9).

As described in detail above, according to the gas leak monitoring device 11 of the present embodiment, the flow meter 33 is disposed between the gas cylinder 21 and the main gas pipe 24 and detects the flow rate of gas.
And a branch pipe 35 downstream of the flow meter 33 for branching the gas flow into a measurement pipe 37 and a bypass pipe 36.
A bypass valve 34 on the bypass pipe 36 for blocking the flow of gas, a bypass valve control program 18 for controlling the opening and closing of the bypass valve 34 in accordance with the gas flow rate measured by the flow meter 33, Storage gas meter 22 for detecting the gas consumption of the gas cylinder 21
When the bypass valve 34 is shut off, a sampling program 15 for sampling the gas consumption of the storage gas meter 22 and the gas consumption of the door-to-door gas meters 23a to 23n at predetermined time intervals at predetermined time intervals.
And the sum S of the gas consumption of the door-to-door gas meters 23a to 23n.
And a gas leak determination program 16 that determines that gas is leaking when the gas consumption amount M of the storage gas meter 22 differs from the gas consumption amount M by a predetermined value N or more.
Alternatively, gas leakage generated in the gas branch pipes 26a to 26n can be detected early and accurately, so that the safety of gas supply can be improved. In addition, gas leaks can be detected regardless of the gas usage status of the equipment used.

The gas leakage monitoring device 11 of this embodiment is also used.
When the gas leak determination program 16 determines that there is a gas leak, the gas leak indicator lamp 3 of the storage unit gas meter 22
Since the gas leak warning is displayed by 0, it is possible to notify a company who frequently exchanges gas cylinders of an apartment house of the gas leak at an early stage. Further, the gas leak monitoring device 11 of the present embodiment is connected to the gas supply central control device 29 via a telephone line.
A signal transmission device 17 connected to and communicable with the gas supply central control device 29 by the signal transmission device 17 when the gas leakage determination program 16 determines that there is gas leakage.
Since the gas leakage alarm is transmitted to the gas supplier, the gas supplier can take prompt action and the safety of gas supply can be further enhanced. Further, when the amount of gas leakage is large, the supply of gas is shut off by the emergency shutoff valve 32, so that occurrence of an accident can be prevented beforehand.

Next, a second embodiment will be described with reference to FIG. This embodiment has substantially the same configuration as the first embodiment, and therefore only different configurations and operations will be described. The gas leakage determination program 16 is not stored in the ROM 14 of the gas leakage monitoring device 11. In addition, the door-to-door gas meter 2
A door-to-door gas leak monitoring device 111 is additionally connected to each of 3a to 23n. In addition, the door-to-door gas leak monitoring device 111
The configuration is similar to that of the gas leakage monitoring device 11, and the telephone line 28 is connected to the gas supply central control device 29 by the signal transmission device 17. On the other hand, the gas supply central controller 29
The ROM 14 stores a gas leak determination program 16 shown in S3 to S7 in FIG. 2 and a bypass valve control program 18 shown in FIG.

The gas leakage monitoring apparatus of the second embodiment having the above structure operates as follows. That is, the gas leakage monitoring device 11 transmits the detection value of the storage gas meter 22 to the gas supply central control device 29 via the telephone line 28 every predetermined time. Further, the door-to-door gas leakage monitoring device 111 transmits the detection values of the door-to-door gas meters 23a to 23n to the gas supply central control device 29 via the telephone line 28 at almost the same timing. Then, the gas leakage determination program 16 uses the storage amount gas meter 22 usage amount M and the door-to-door gas meter 23a.
Ｎ23n is calculated (S3, S4), and if the absolute value of the difference is larger than N (S5, YES), it is determined that gas leakage has occurred (S6). Here, the value of N is determined according to each gas supply system by the accuracy of the storage unit gas meter 22 and the door-to-door gas meters 23a-23n, the length of the piping system, and the like. Further, when the amount of leaking gas is equal to or exceeds the predetermined amount L (S
8, YES), since there is a fear of an accident due to the leaked gas, the gas supply central controller 29 shuts off the gas supply by the emergency shutoff valve 32 via the telephone line (S9).

As described above, according to the gas leakage monitoring device of the second embodiment, the door-to-door gas leakage monitoring device 111 connected to the door-to-door gas meters 23a to 23n and the gas leakage monitoring device 11 connected to the storage gas meter 22 are telephones. The gas supply central control device 2 is provided with a signal transmission device 17 that is connected to the gas supply central control device 29 through a line and is capable of communication.
Since 9 has the gas leak judgment program 16, when the automatic meter reading system of the door-to-door gas meters 23a to 23n is adopted, the gas leak judgment program 16 is sent to the gas leak monitoring device 11 and the door-to-door gas leak monitoring device 111. Since it is not necessary to provide the function of, the gas leakage monitoring device 11 can use a simple microcomputer of the same level as the gas leakage monitoring device 111, and the cost can be reduced.

The above-described embodiment does not limit the present invention in any way, and various modifications and improvements can be made without departing from the scope of the present invention. For example, in the present embodiment, the door-to-door gas leakage monitoring device 111 has a configuration different from that of the door-to-door gas meters 23a to 23n, but the same is true even if both are integrated by a so-called microcomputer gas meter.

[0025]

As is apparent from the above description, according to the gas leakage monitoring device of the present invention, a flow meter disposed between the gas storage section and the piping system for detecting the flow rate of the fuel gas, and a flow rate A branch pipe downstream of the meter that divides the flow of fuel gas into a measurement pipe and a bypass pipe, a bypass valve on the bypass pipe that blocks the flow of fuel gas, and a gas measured by the flow meter. Bypass valve control means for controlling the opening and closing of the bypass valve according to the flow rate, a storage portion gas meter on the measuring pipe for detecting the fuel gas consumption of the gas storage portion, and a predetermined value when the bypass valve is shut off Sampling means for sampling and calculating the gas consumption amount of the storage gas meter and the gas consumption amount of the door-to-door gas meter for each predetermined time, and the sum of the gas consumption amount of the door-to-door gas meter and the storage gas meter Since the gas leak judgment means that judges that gas is leaking when the gas consumption amount differs by more than a predetermined value can be detected early and accurately, the gas supply occurring in the gas piping system can be detected. Can increase the safety of.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a gas leak monitoring device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the gas leakage monitoring device.

FIG. 3 is a flowchart showing the action of a bypass valve.

FIG. 4 is a block diagram showing a configuration of a gas leakage monitoring device according to a second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 11 gas leak monitoring device 12 CPU 13 RAM 14 ROM 15 sampling program 16 gas leak judgment program 17 signal transmission device 18 bypass valve control program 21 gas cylinder 22 storage gas meter 23 door-to-door gas meter 24 gas main pipe 26 gas branch pipe 28 telephone line 29 gas supply Central control unit 32 Emergency shut-off valve 33 Flow meter 34 Bypass valve 36 Bypass pipe 37 Measurement pipe

Claims (5)

[Claims] 1. A gas storage unit for storing fuel gas for supply to an apartment house, a piping system for supplying fuel gas from the storage unit to each unit of the apartment house, and a fuel gas consumption amount for each unit. A gas leak monitoring device for detecting a gas leak in a gas supply system having a door-to-door gas meter for detecting, wherein a flow meter disposed between the gas storage unit and the piping system to detect a flow rate of the fuel gas A branch pipe downstream of the flow meter and branching the flow of the fuel gas into a measurement pipe and a bypass pipe; and a bypass on the bypass pipe and blocking the flow of the fuel gas. A valve; bypass valve control means for controlling opening and closing of the bypass valve in accordance with a gas flow rate measured by the flow meter; and detecting fuel gas consumption of the gas storage unit on the measurement pipe. A storage unit gas meter, and when the bypass valve is shut off, at predetermined time intervals, sampling means for sampling and calculating the gas consumption amount of the storage unit gas meter at the predetermined time period and the gas consumption amount of the door-to-door gas meter, Gas leak determining means for determining that gas is leaking when the sum of the gas consumption of the door-to-door gas meter and the gas consumption of the storage unit gas meter differ by a predetermined value or more. Monitoring device. 2. The gas leak monitoring device according to claim 1, wherein when the gas leak judging means judges that there is gas leak, a gas leak alarm is displayed on the storage gas meter. 3. The communication device according to claim 1, further comprising communication means connected to the central gas supply control device via a telephone line, wherein the gas leak determination means determines that there is a gas leak. A gas leak monitoring device for transmitting a gas leak alarm to the gas supply central control device by means of: 4. The gas supply central controller according to claim 1, wherein the door-to-door gas meter and the storage gas meter have communication means connected to a gas supply central controller by a telephone line. A gas leakage monitoring device having a leakage determination means. 5. The apparatus according to claim 1 or 4, further comprising a shutoff means for shutting off gas supply when the gas leak determination means determines that there is a gas leak of a predetermined amount or more. A gas leakage monitoring device.