JP3368685B2 - Piping leak detection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe leakage detecting device for automatically detecting the presence or absence of gas leakage in the upstream pipes of a plurality of gas meters.

[0002]

2. Description of the Related Art Conventionally, as a first conventional example, gas leak detection in the upstream pipes of a plurality of gas meters has been carried out as a practical example.
The configuration as shown in Japanese Patent No. 0343 has been general. The configuration will be described below with reference to FIGS. 7 and 8.

As shown in the figure, each of the collective housing 4 in the private area M from the gas collective supply means 1 such as a gas concentrated supply pipeline in the public area P through the branch means 3 by the gas supply pipe 2 Gas is supplied to the gas meter 5 provided in the house. A gas instrument 6 is connected to each gas meter 5 to receive gas supply. A gas total flow rate measuring means 7 for measuring the total flow rate of the gas supplied to all gas meters 5 is connected between the gas collective supply means 1 and the branching means 3, and the gas leak upstream of the gas meter is measured by the measured flow rate value information. It has a pipe leakage judging means 8 for judging. Information on pipe leakage determination is
It is sent to the centralized monitoring center 11 through the telephone network control device 9 and the telephone line 10 to be dealt with.

In addition, as a second conventional example, a configuration similar to the above is used, in which the total sum of gas flow rates detected by each gas meter 5 is calculated and compared with the total gas flow rate measurement value of the total gas flow rate measuring means. It is disclosed in Japanese Patent Laid-Open No. 4-363638.

The flow rate characteristic of the gas meter common to the above conventional example will be described with reference to FIG. The gas meter can flow up to the maximum usable flow rate M as the gas flow rate to the gas appliance, and the lowest flow rate is 500 Kca when the gas stove is used.
It is about l / h. The maximum use flow rate M changes depending on the amount of gas appliances owned by each house, and the capacity of the gas meter is also selected accordingly. Therefore, the safe gas usage monitoring range is from 500 Kcal / h to the maximum flow rate M.
If it exceeds that, it is common that the gas meter shuts off the gas by energizing the shutoff function possessed by the gas meter as an unsafe condition such as disconnection of the gas hose or breakage of the pipe.
In addition, the gas meter has the function of detecting gas leakage in the downstream of the gas meter, and monitors the flow rate from the leak judgment value (about 20 Kcal / h) to the lower limit value of 500 Kcal / h of the safe use monitoring area of gas. , When a gas having a leakage determination value L or more continues to flow for 30 consecutive days, an alarm indicating downstream leakage is issued. However, for gas appliances with igniting, the typical igniting flow rate range is 200 Kcal / h
Since it enters the downstream leakage detection area at about 300 Kcal / h, if the ignition is left unchecked, an alarm indicating downstream leakage will be issued. In order to avoid this, the method of registering or automatically detecting the ignition flow rate of the house and ignoring the detected flow rate is adopted.

In the configuration of the first conventional example described above, the total gas flow rate measuring means 7 is provided under the expectation that the gas appliances of all the houses will not be used at the same time even in an apartment house.
When the gas flow rate was continuously measured for 30 days and the measured flow rate value was determined by the pipe leakage determination means 8 to always exceed the leak determination value L, it was determined that there was a gas leak upstream of the gas meter.

Further, in the second conventional example, the total sum of gas flow rates detected by each gas meter 5 is subtracted from the total flow rate measurement value by the gas total flow rate measuring means, and if the value is positive, it is upstream of the gas meter. It was determined that there was a gas leak.

[0008]

In the pipe leakage detection device as in the first conventional example, the pipe leakage determination is performed with the expectation that there is a period in which the gas appliances 6 in all homes are not used at the same time. As the number of apartments 4 grows and the living styles of residents change, is there really a gas leak upstream of the gas meter 5?
However, there is a problem in that the reliability of the leak determination by the pipe leak determination means 8 is significantly reduced due to the ambiguity of continuous use.

In the second conventional example, the gas flow rate measurement is ±
Since there is an error of about 3%, the error between each gas meter and the total gas flow rate measuring means is overlapped and expanded, and the value of the subtraction result becomes positive even if there is no gas leak, or even if a gas leak occurs. There was a problem that the reliability of the leak judgment was significantly reduced due to the negative value.

Further, as a problem common to the first and second conventional examples, since the number of connected gas appliances is large in a large-scale housing complex with more than 100 units, the total allowable leakage when the gas appliances are closed is large. There was a case where the value exceeded the pipe leakage determination value and there was no pipe leakage, but it was determined that there was pipe leakage. Assuming that there are 3 kitchens for each gas appliance, the number of connected gas appliances is 450 in a housing complex of 150 houses, for example. In addition, the permissible leakage when the gas appliance is closed is generally considered to be about 0.07 l / h, so a maximum of 0.07 x 450 = 3 for the apartment house.
It is necessary to allow a leak of 1.5 l / h, but since it exceeds the leak judgment value (about 20 Kcal / h),
There was a problem that pipe leakage did not occur and it was determined that there was pipe leakage even if all gas appliances were normal.

The present invention solves the above problems, and a first object thereof is to enhance the reliability of automatic leakage determination.

[0012] A second object is to prevent an unsafe state from occurring during use of the gas appliance during the automatic leak detection.

A third purpose is to prevent the convenience of the occupant from being impaired by the automatic leakage detection.

A fourth object is to facilitate the installation of this device in an apartment house.

[0015]

In order to achieve the above object, the present invention has a first configuration in which a gas group supply means for supplying gas and a meter flow rate detection unit incorporated in a gas meter for detecting a gas flow rate. Means, a gas meter built-in, instrument usage determination means for determining whether or not a gas appliance is used by the detected flow rate from the meter flow rate detection means, and a gas meter built-in supply control means for opening and closing the gas, A gas supply pipe for supplying the gas supplied from the gas collective supply means to each gas meter through the branching means, and a gas total flow rate measuring means provided between the gas collective supply means and the branching means for measuring the total gas flow rate. And a gas appliance comprehensive judgment means for performing a comprehensive monitoring of gas appliance usage based on the information from the appliance usage judgment means of each gas meter and a gas appliance comprehensive judgment means. A meter opening / closing control means for instructing the gas meter supply means to open / close the gas supply when it is determined that the usage information is simultaneously established, and a gas total flow rate measuring means when the gas supply is closed in conjunction with the gas supply open / close control. Is provided to measure the total flow rate of gas.

In the second configuration, a pressure sensor is provided in the gas meter downstream of the supply control means to detect the gas pressure, and the gas pressure detected by the pressure sensor when the supply control means is instructed to open is predetermined. When it is lower than the value of, the opening prohibition means for prohibiting the opening instruction is provided.

A third structure is a pressure sensor provided on the gas meter downstream of the supply control means for detecting the pressure of gas,
When the gas pressure detected by the pressure sensor is lower than a predetermined value when the supply control means is closed, a pressure reduction opening means for urging the supply control means to open the gas is provided. .

In a fourth configuration, the first wireless means for transmitting the information of the instrument usage determining means together with the identification code of the gas meter to receive the information of the meter opening / closing control means, and the transmission information from the instrument usage determining means. The second wireless means for transmitting the information of the meter opening / closing control means is provided.

[0019]

According to the first aspect of the present invention, the meter opening / closing control means energizes and closes the supply means of each gas meter when it is judged by the appliance use comprehensive judgment means that all gas appliances are not used. At the same time, the gas total flow rate measurement means is activated from the measurement control means to perform the gas total flow rate measurement. As a result, pipe leak detection can be performed without limiting the gas usage of the occupants and without being affected by the allowable leak of gas appliances.

According to the second configuration, the meter opening / closing control means energizes and closes the supply means of each gas meter, and at the same time the measurement control means energizes the gas total flow rate measuring means to measure the gas total flow rate. When a resident accidentally uses a gas appliance and gives up using gas because the gas does not come out and the gas appliance is left open, the pressure sensor detects the gas pressure drop due to the opening of the gas appliance. As a result, when the measurement control means gives an opening instruction to the supply means of each gas meter after measuring the total gas flow rate, it is possible to prohibit the opening instruction of only that gas meter, and prevent the release of raw gas from the gas appliance. it can.

According to the third structure, the meter opening / closing control means energizes and closes the supply means of each gas meter, and at the same time the measurement control means energizes the gas total flow rate measuring means to perform the gas total flow rate measurement. When a resident accidentally opens the gas appliance to use the gas appliance while operating, the pressure sensor detects the gas pressure drop due to opening the gas appliance and activates the supply means of each gas meter from the meter opening / closing control means. By opening and supplying the gas, it is possible to prevent the resident from using the gas.

Further, according to the fourth configuration, since information is exchanged between the gas meter and the appliance use comprehensive judgment means or the meter opening / closing control means by using the first wireless means and the second wireless means, This device can be installed easily even in a building where it is not possible to wire from each gas meter to the instrument usage comprehensive judgment means or the meter opening / closing control means in a prefabricated housing complex using reinforcing bars.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG. The same parts as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted.

As shown in the figure, the gas meter 5 has a meter flow rate detecting means 12 for measuring the flow rate of gas passing through the meter, and whether or not a gas appliance is used depending on the flow rate detected by the meter flow rate detecting means 12. Device use determination means 13 for determining the gas flow rate, and supply control means 1 for opening and closing the gas
4 and are provided.

Further, based on the information from the appliance usage determination means 13, the appliance usage comprehensive judgment means 15 for performing a comprehensive monitoring of the gas appliance usage of the housing complex based on the information from the appliance usage usage determination means 13 and the supply control means for each meter based on the information from the appliance usage comprehensive judgment means 15. A meter opening / closing control means 16 for instructing 14 to open / close gas supply and a measurement control means 17 for controlling the gas total flow rate measuring means 7 in cooperation with the meter opening / closing control means 16 are provided.

To explain the operation in the above structure, the gas flow rate measured by the meter flow rate detecting means 12 drops significantly to the value of the gas appliance allowable leak when the gas appliance 6 connected to the gas meter 5 becomes unused. Instrument usage determination means 1
The gas meter 5 judges that the gas meter 5 is in the state of non-use of the gas appliance by catching the change, and the appliance usage comprehensive judgment means 1
Send the information to 5. When the gas appliance non-use information from each gas meter is established at the same time, the appliance usage comprehensive judgment means 15 judges that the gas appliances are not being used in this apartment house at present, and controls the supply of all gas meters via the meter opening / closing control means 16. The means 14 are energized and closed. Simultaneously with closing, the gas total flow rate measuring means 7 is energized via the measurement control means 17 to measure the gas flow rate for, for example, 10 seconds. At this time, if the value exceeds the pipe leakage determination value (about 20 Kcal / h), the pipe leakage determining means 8 determines that there is a pipe leakage. When the gas flow rate measurement means 7 completes measuring the gas flow rate for about 10 seconds, the supply control means 14 of all gas meters are energized and opened via the meter opening / closing control means 16. Therefore, since the supply control means 14 is closed / opened for a short time when the gas appliance is not originally used, there is no influence on the convenience of using the gas appliance to the resident, and the gas total flow rate measuring means 7 is used. Since the gas flow rate measurement is performed with the supply control means 14 of all the gas meters closed, it is possible to detect the pipeline leak without being affected by the allowable leak of the gas appliance.

Next, a second embodiment of the present invention will be described with reference to FIG. As shown in the figure, the gas meter 5
Gas pressure sensor 18 provided on the downstream side of the supply control means 14
And an opening prohibiting means 19 for prohibiting the opening instruction of the meter opening / closing control means 16 when the gas pressure detected by the pressure sensor 18 when the supply control means 14 is closed falls below a predetermined value. .

To explain the operation in the above configuration, if the gas instrument 6 is used for 10 seconds for gas flow rate measurement, the upstream side of the pressure sensor 18 is closed by the supply control means 14 and the downstream side. The gas pressure detected by the pressure sensor 18 finally decreases to zero because the gas pressure is released by the use of the gas appliance 6. As a result, when the total gas flow rate measuring means 7 finishes measuring the gas flow rate and the meter opening / closing control means 16 issues an opening instruction, the opening prohibition means 19 prohibits the instruction, so that the supply control means 14 continues to close. . Therefore, although the occurrence probability is low, the resident used the gas appliance 6 without a safety device for 10 seconds for measuring the gas flow rate, and gave up using the gas appliance because the gas did not catch fire, and the gas appliance was opened. Even if the gas meter is left as it is, the gas is not supplied from the gas meter, so that safety can be ensured.

Next, a third embodiment of the present invention will be described with reference to FIG. As shown in the figure, the gas meter 5
When the gas pressure detected by the pressure sensor 18 drops below a predetermined value when the supply control means 14 is closed, the supply control means 14 is opened to supply the gas with a pressure reduction opening means 20. .

The operation of the above configuration will be described. If the gas instrument 6 is used for 10 seconds for measuring the gas flow rate, the upstream side of the pressure sensor 18 is closed by the supply control means 14 and the downstream side. The gas pressure detected by the pressure sensor 18 finally decreases to zero because the gas pressure is released by the use of the gas appliance 6. The gas pressure drop is within a region where the use of the gas appliance is not hindered, and the pressure drop opening means 2
When it is determined as 0, the supply control means 14 is opened to restart the gas supply so that the convenience of the resident for using the gas appliance is not affected.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. As shown in the figure, in the first embodiment, first wireless means 21 for wirelessly transmitting the information of the gas meter 5 together with the identification code of the gas meter and wirelessly receiving the information from the second wireless means described later, and the first wireless means 21 thereof. Transmitting to the wireless means 21, sequentially calling each gas meter using the identification code, transmitting the opening / closing instruction of the meter opening / closing control means 16 to each supply control means 14, and receiving the information of the first wireless means 21 to comprehensively use the equipment. The second wireless means 22 for transmitting information is added to the judging means 15.

To explain the operation of the above configuration, the second wireless means 22 appropriately sends a signal to the first wireless means 21 and sequentially calls each gas meter using the identification code. The called gas meter wirelessly transmits the information of the appliance usage determining means 13 together with the identification code of the gas meter by the first wireless means 21, which is received by the second wireless means 22 and transmitted to the overall appliance usage determining means 15, The opening / closing instruction of the opening / closing control means 16 is transmitted to each supply control means 14. Therefore, particularly in an existing housing complex requiring this pipe leakage detection device, reinforced concrete work or the like is required at each place to connect the gas meter 5 of each house to the appliance usage comprehensive determination means 15 and the meter opening / closing control means 16. In many cases, however, it is not possible to install it substantially, but in this embodiment, the wiring work is not required, the installation is facilitated, and the safety of the existing housing complex can be improved. In addition, since transmissions do not overlap at the same time, there is no useless time delay such as transmission waiting and retransmission, and information transmission can be facilitated even in special apartments with a large number of homes, which is safe. Can be increased.

In the above-mentioned embodiment, the appliance use comprehensive judgment means 15 causes the gas integrated flow rate measuring means 7 to perform the gas flow rate measurement at the time when the gas appliance non-use information of each house overlaps. This means that the measured value of the gas flow rate by the gas total flow rate measuring means 7 when the gas appliance is used is not used for judging the gas leakage, and the gas flow rate measurement by the gas total flow rate measuring means 7 when the gas appliance is used for other purposes. If a value is required, the gas total flow rate measuring means 7 will naturally measure the gas flow rate even when using a gas appliance. Further, the first wireless means 21 may be built in the gas meter 5 or may be externally attached, and the second wireless means 22 may be built in the appliance use comprehensive judgment means 15 or the meter opening / closing control means 16 or externally attached. However, the present invention is not limited to this embodiment.

[0034]

As is apparent from the above description, according to the present invention, the instrument use determination means for determining whether or not the gas instrument is used is detected by the flow rate detected by the meter flow rate detection means, and the gas is opened and closed. A plurality of gas meters having a supply control means, a gas supply pipe for supplying the gas supplied from the gas group supply means to each gas meter through the branching means, and a gas provided between the gas group supply means and the branching means Gas total flow rate measuring means for measuring the total flow rate of
Gas meter supply means for performing comprehensive monitoring of gas appliance use based on information from the appliance usage determination means of each gas meter, and gas meter supply means when simultaneous determination of gas appliance non-use information is determined by the appliance usage comprehensive determination means The meter opening / closing control means for opening / closing the gas supply and the measurement control means for energizing the gas total flow rate measuring means when the meter is closed to measure the total gas flow rate. When the instrument use comprehensive determination means determines that all gas appliances are not used, the meter opening / closing control means energizes and closes the supply means of each gas meter, and the measurement control means adds the total gas flow rate measuring means. Since the total gas flow rate measurement is performed by encouraging the residents, the resident may stop using the gas for a certain period of time or stop using it while using the gas. It is little to affect the convenience of use. In addition, since the meter is closed and the total gas flow rate is measured, reliable piping leak detection can be performed, operation errors do not occur, and pipe leakage detection can be performed without being affected by the allowable leakage of gas appliances. It is possible to detect pipe leaks with high reliability even in large-scale apartments with a large number of units, which was difficult in the past.

In the gas meter, the gas pressure sensor provided on the downstream side of the supply control means and the gas pressure detected by the pressure sensor when the supply control means is instructed to open are lower than a predetermined value. In this case, since the opening prohibition means for prohibiting the opening instruction is provided, the meter opening / closing control means energizes and closes each gas meter supply means, and the measurement control means energizes the gas total flow rate measurement means. Even when the resident uses a gas appliance without a safety device while measuring the total gas flow rate and gives up using the gas appliance because the gas does not ignite, and even if the gas appliance is left open By detecting the decrease in gas pressure due to the opening of gas appliances with a pressure sensor, when the measurement control means gives an instruction to open to the supply means of each gas meter after the total gas flow rate is measured. Gas meter only be able to prohibit the open instruction, to prevent the raw gas discharged from a gas appliance it is possible to ensure the safety. In addition, the gas supplier does not affect other meters, and even for the meter for which the opening instruction is prohibited, the gas supplier only closes the gas appliance once for the resident and opens the supply control means from the center. It has the feature that it can be handled.

Further, in the gas meter, a gas pressure sensor provided on the downstream side of the supply control means, and when the gas pressure detected by the pressure sensor when the supply control means is closed falls below a predetermined value, Since the pressure drop opening means for urging the supply control means to open it is provided, the meter opening / closing control means urges and closes the supply means of each gas meter, and the measurement control means adds the total gas flow rate measuring means. Even when the resident opens the gas appliance to use the gas appliance while conducting a total gas flow measurement,
By detecting the gas pressure drop due to the opening of gas appliances with a pressure sensor and activating the supply means of each gas meter from the meter opening and closing control means to open and supply the gas, priority is given to the resident's use of gas over the work of automatic leak detection However, it is possible to prevent the convenience of residents from being impaired.

Further, the first wireless means for wirelessly transmitting the information of the gas meter together with the identification code of the gas meter and wirelessly receiving the information from the second wireless means which will be described later, and transmitting the identification code for the first wireless means. Using the second wireless means for sequentially calling each gas meter using the above, transmitting the opening / closing instruction of the meter opening / closing control means to each supply control means, and receiving the information of the first wireless means and transmitting the information to the instrument use comprehensive determination means. Since the addition is made, it is possible to exchange information between the gas meter and the appliance usage comprehensive determination means or the meter opening / closing control means via the air using the first wireless means and the second wireless means. Therefore, even in a prefabricated apartment building where it is not possible to wire from each gas meter to the appliance usage comprehensive judgment means or meter opening / closing control means, the installation of this device can be prepared easily, and the safety of the apartment house can be improved. Can be done. In addition, since transmissions do not overlap at the same time, there is no useless time delay such as transmission waiting and retransmission, and information transmission can be facilitated even in special apartments with a large number of homes, which is safe. Can be increased.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a pipe leakage detection device according to a first embodiment of the present invention.

[Fig. 2] Layout plan of the device

FIG. 3 is a functional block diagram of a pipe leakage detection device according to a second embodiment of the present invention.

FIG. 4 is a functional block diagram of a pipe leakage detection device according to a third embodiment of the present invention.

FIG. 5 is a functional block diagram of a pipe leakage detection device according to a fourth embodiment of the present invention.

FIG. 6 is a layout diagram of the device.

FIG. 7 is a functional block diagram of a conventional pipe leakage detection device.

[Fig. 8] Layout plan of the device

FIG. 9 is a gas flow rate characteristic diagram of the gas meter of the same device.

[Explanation of symbols]

1 gas group supply means 2 gas supply pipes 3 branching means 5 gas meters 7 Gas total flow rate measuring means 8 Piping leakage determination means 12 meter flow rate detection means 13 Instrument usage determination means 14 Supply control means 15 Instrument usage comprehensive judgment 16 meter opening / closing control means 17 Measurement control means 18 Pressure sensor 19 Open prohibition means 20 Pressure drop opening means 21 First wireless means 22 Second wireless means

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Claims (4)

(57) [Claims] 1. A gas collective supply means for supplying a gas, a meter flow rate detection means built in a gas meter for detecting a gas flow rate, and a gas appliance used by a flow rate detected by the meter flow rate detection means built in a gas meter. A tool use determination means for determining whether or not there is a supply control means for opening and closing the gas built in the gas meter, and a gas supply for supplying the gas supplied from the gas collective supply means to each of the gas meters via a branching means. Comprehensive monitoring of gas appliance use is performed by means of a pipe, a gas total flow rate measuring means provided between the gas collective supply means and the branching means to measure the total gas flow rate, and information from the appliance use determining means of each gas meter. When the gas appliance non-use information is determined to be established at the same time by the appliance usage comprehensive judgment means and the appliance usage comprehensive judgment means, The meter opening / closing control means for instructing the gas supply means to open / close the gas supply, and the gas total flow rate measuring means is energized to measure the total gas flow rate when the gas supply is closed in association with the gas supply open / close control. A pipe leakage detection device configured with measurement control means. 2. A gas meter, which is provided on the downstream side of the supply control means, detects a gas pressure, and the gas pressure detected by the pressure sensor when an instruction to open the supply control means is lower than a predetermined value. The pipe leakage detection device according to claim 1, further comprising an opening prohibition unit that prohibits the opening instruction when the pipe leakage detection device does. 3. A gas meter is provided with a pressure sensor provided on the downstream side of the supply control means to detect the pressure of the gas, and when the gas pressure detected by the pressure sensor when the supply control means is closed falls below a predetermined value. The pipe leakage detection device according to claim 1, wherein the pipe leakage detection device has a pressure reduction opening means for energizing the supply control means to open the supply control means. 4. A first wireless means for transmitting the information of the instrument usage determining means together with the identification code of the gas meter and receiving the information of the meter opening / closing control means, and the transmission information from the instrument usage determining means for opening / closing the meter. The pipe leakage detection device according to claim 1, further comprising a second wireless unit that transmits information of the control unit.