JP5032095B2 - Gas shut-off system - Google Patents

Description

  The present invention provides an emergency shut-off device in a pressure regulator for adjusting the pressure of gas provided in the middle of a gas supply path, and operates the emergency shut-off device as necessary to supply gas downstream of the pressure regulator. The present invention relates to a gas shut-off system that shuts off.

As a conventional gas shut-off system, a seismometer is provided in a governor room equipped with a pressure regulator, and when the detected value by the seismometer exceeds a predetermined reference value, an emergency shut-off device is activated to operate the pressure regulator. One that shuts down the gas supply to the downstream is known (for example, see Patent Document 1).
JP 2001-116200 A ([0039] to [0041], FIG. 1)

  However, in the above-described conventional gas shut-off system, for example, an emergency caused by vibrations unrelated to earthquakes such as construction performed near the governor room, passage of a large vehicle, or mischief that intentionally vibrates the seismometer itself. There was a possibility that the shut-off device malfunctioned and caused great trouble for the gas user.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a gas shut-off system capable of preventing the operation of an unnecessary emergency shut-off device.

In order to achieve the above object, a gas shutoff system according to the invention of claim 1 is provided in the middle of a gas supply path and disposed in a governor chamber, and an emergency shutoff device is provided in a pressure regulator for adjusting the gas pressure. A seismometer capable of detecting an earthquake exceeding a predetermined reference seismic intensity and a pressure regulator in a gas cutoff system that shuts off the gas supply downstream of the pressure regulator by operating an emergency cutoff device if necessary A flow rate detection means capable of detecting the flow rate of gas flowing in or a substitute value thereof , and an abnormal flow rate as a result of the gas flow rate or substitute value being equal to or greater than the upper limit value of a reference allowable range set in advance for each time zone. together determine the flow rate abnormality detection means for determining the flow rate abnormality with a possible equal to or less than a lower limit value of the reference tolerance, and the requirements that both the reference seismic intensity or earthquake and flow rate abnormality occurs, emergency barrier At which a operation command means for operating the device with the features.

  The invention according to claim 2 is characterized in that, in the gas shut-off system according to claim 1, the flow rate detecting means detects the valve opening of the pressure regulating valve provided in the pressure regulator as a substitute value of the gas flow rate.

  According to a third aspect of the present invention, in the gas shut-off system according to the first or second aspect, the flow rate detecting means detects the differential pressure before and after the throttle portion provided upstream of the pressure regulator as a substitute value of the gas flow rate. However, it has characteristics.

According to a fourth aspect of the present invention, in the gas shut-off system according to any one of the first to third aspects, the pressure regulator monitoring computer to which the detection results of the seismometer and the flow rate detection means are input, It is characterized in that it is provided with a shutoff determination program for functioning as an abnormality detection means and an operation command means.

According to a fifth aspect of the present invention, in the gas shutoff system according to the fourth aspect , the shutoff determination program stores an actual measured value of the gas flow rate or a substitute value for each time zone in a normal time, and the stored data is stored in the stored data. Based on this, the pressure regulator monitoring computer functions as a reference allowable range setting means for updating and setting the reference allowable range of the gas flow rate or its substitute value for each time zone. It is characterized in that a flow rate abnormality is detected when the gas flow rate or its substitute value deviates from the reference allowable range for each time zone set by the means.

According to a sixth aspect of the present invention, in the gas shutoff system according to the fourth or fifth aspect, the pressure regulator monitoring computer is disposed at a remote location away from the pressure regulator and the pressure regulator and the pressure regulator are monitored via the data communication network. A data communication terminal for transmitting and receiving an operation control signal to the seismometer and the flow rate detection means between the pressure regulator and the pressure regulator monitoring computer. It is characterized by being provided in the pressure regulator and the computer for monitoring the pressure regulator.

According to a seventh aspect of the present invention, in the gas shut-off system according to the sixth aspect , the detection results of the seismometers and the flow rate detecting means provided in the plurality of pressure regulators function as a flow rate abnormality detecting means and a shut-off valve operation command means. It is characterized in that it is configured to be processed by a computer for monitoring the pressure regulator of the table.

The invention according to claim 8 is characterized in that, in the gas shutoff system according to claim 6 or 7 , the data communication network is a PHS line.

The invention according to claim 9 is the gas shutoff system according to any one of claims 6 to 8 , wherein data transmission from the pressure regulator side to the pressure regulator monitoring computer is impossible, or from the pressure regulator to the pressure regulator monitoring It has a feature in that it includes auxiliary operation command means for activating the emergency shut-off device when a response to the data transmission to the computer is not sent from the pressure regulator monitoring computer to the pressure regulator.

According to a tenth aspect of the present invention, in the gas cutoff system according to the ninth aspect , an auxiliary monitoring computer is provided on the pressure regulator side, and the auxiliary monitoring computer functions as a flow rate abnormality detecting means and an auxiliary operation command means. It has a feature in that an auxiliary shut-off determination program is provided.

The invention according to claim 11 is the gas shutoff system according to any one of claims 1 to 10, wherein a large earthquake base seismic intensity greater than the base seismic intensity is set and an earthquake greater than the base earthquake seismic intensity is detected. Is characterized in that it is configured to operate the emergency shut-off device even if a flow rate abnormality does not occur .

[Inventions of Claims 1 and 3]
When an earthquake of a scale that could cause a disaster occurs, an abnormality occurs in the gas supply path, or the gas user closes the gas plug, etc., so that the gas flow rate or its substitute value is the same as the normal flow rate. Have different values. In other words, if the gas flow rate or its substitute value is an earthquake that does not differ from the normal flow rate or an earthquake that is transmitted to the ground, no disaster caused by gas occurs. In the present invention, since the emergency shut-off device is operated on the condition that both an earthquake exceeding the reference seismic intensity and an abnormal flow rate have occurred, the emergency shut-off device is operated unnecessarily (gas is shut off). Is prevented. Moreover, even when an earthquake actually occurs, the emergency shut-off device can be operated only for an earthquake of a scale that may cause a disaster. And since the emergency shut-off device is provided in the pressure regulator, it is possible to prevent a disaster caused by the gas in a wide range where the gas supply path is stretched. Here, as a substitute value of the gas flow rate, the differential pressure before and after the throttle portion provided on the upstream side of the pressure regulator may be used (invention of claim 3).

[Invention of claim 2]
According to invention of Claim 2, it becomes unnecessary to provide a flowmeter separately, and cost reduction is achieved.

[Invention of claim 4 ]
When the reference allowable range serving as a reference when the flow rate abnormality detecting means detects the flow rate abnormality is made different for each region, it can be easily handled by changing the monitoring program.

[Invention of claim 5 ]
According to the invention of claim 5 , since the reference allowable range of the gas flow rate or its substitute value is updated based on the actual detection result, even if the amount of gas used changes due to increase / decrease in users or seasonal changes In accordance with this, a reference allowable range is automatically set.

[Invention of claim 6 ]
According to the invention of claim 6 , the emergency shut-off device provided in the pressure regulator can be operated at a remote place. Here, the data communication network may be a wired communication network (for example, an optical fiber communication network), a wireless communication network, or a combination thereof.

[Invention of Claim 7 ]
According to the invention of claim 7 , the emergency shut-off device provided in each of the plurality of pressure regulators can be operated by one pressure regulator monitoring computer.

[Invention of Claim 8 ]
In the invention of claim 8 , since the PHS line is used for data communication performed between the pressure regulator and the pressure regulator monitoring computer, it is necessary to connect the pressure regulator and the pressure regulator monitoring computer with a communication cable. Therefore, data communication can be easily performed.

[Inventions of Claims 9 and 10 ]
According to the invention of claim 9 , in the event that an earthquake exceeding the reference seismic intensity occurs, even if data communication between the pressure regulator and the pressure regulator monitoring computer is not possible, the auxiliary operation command means Since the shut-off device operates, it is possible to reliably prevent a disaster caused by gas. Specifically, an auxiliary monitoring computer is provided on the pressure regulator side, and an auxiliary shut-off determination program for causing the auxiliary monitoring computer to function as a flow rate abnormality detecting means and an auxiliary operation command means may be provided ( (Invention of Claim 10 )

According to the configuration of claim 11, when a huge earthquake with a high probability of occurrence of a disaster occurs, it is possible to reliably operate the emergency shut-off device and prevent a disaster caused by gas.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows a conceptual diagram of a gas shutoff system 100 of the present invention applied to a city gas supply network. The supply area in which the city gas supply network is stretched is usually divided into a plurality of regional blocks, and a governor room 10 is provided in each of the plurality of regional blocks.

  The governor chamber 10 includes a pressure regulator 11 as a main part. The pressure regulator 11 reduces the gas at a relatively high pressure (for example, 100 KPa or more) supplied from the gas manufacturing factory 60 to a predetermined set pressure (for example, less than 3 KPa). The valve opening is automatically adjusted so that it is always almost constant at the set pressure. Further, the governor room 10 is provided with an emergency shut-off device 12 (see FIG. 2), and when an abnormality occurs in the area block where the governor room 10 is installed, The supply of gas into the regional block (downstream from the pressure regulator 11) is stopped.

  The gas shutoff system 100 according to the present invention includes a plurality of governor chamber units 20 (see FIG. 2) respectively provided in the plurality of governor chambers 10, and the governor chambers 10 through the governor chamber units 20. A governor monitoring computer 50 (corresponding to the “pressure regulator monitoring computer” of the present invention) for collectively managing the pressure regulator 11 and the emergency shut-off device 12 is provided, and these are connected to a data communication network (specifically, a public network). In this configuration, communication is possible via a PHS line.

  The governor monitoring computer 50 is installed in a centralized monitoring center 51 located in a remote place away from each governor room 10. The governor monitoring computer 50 collects each detection data of the primary pressure of the pressure regulator 11 and the valve opening of the pressure regulating valve from the governor chamber unit 20 and stores it in the storage device. In addition, among these detection data, the detection data of the valve opening as the “substitute value of the gas flow rate” according to the present invention is compared with a reference allowable range stored in advance in a memory (ROM), and whether or not an abnormality has occurred Is determined. Then, a pressure regulator stop signal (corresponding to the “operation control signal” of the present invention) is selectively output to the governor chamber unit 20 which is the transmission source of the detected data determined to be abnormal. Then, the emergency shut-off device 12 of the governor chamber 10 is activated, the pressure regulating valve of the pressure regulator 11 is fully closed, and the gas supply is stopped in the area block. Here, the reference permissible range is set for each time zone based on the actually observed long-term fluctuation and transition pattern of the valve opening for each area block in which the governor chamber 10 is located. FIG. 5B shows an example of a graph showing the variation and transition of the valve opening.

  As shown in FIG. 2, the governor chamber 10 includes a seismometer 15, a pressure sensor 13 for detecting the primary pressure of the pressure regulator 11, and a valve for detecting the valve opening of the pressure regulator of the pressure regulator 11. An opening meter 14 is provided.

  The seismometer 15 detects ground vibration (specifically, vibration acceleration) observed at a point in the governor room 10 when an earthquake occurs. When a vibration corresponding to a predetermined reference seismic intensity (e.g., 60 kines in terms of SI value) or more is detected, a signal is output to the CPU 22 of the governor room unit 20. Then, the CPU 22 outputs an alarm signal to the governor monitoring computer 50 through the PHS module 24 (corresponding to the “data communication terminal” of the present invention).

  The pressure sensor 13 is provided on the upstream side of the pressure regulator 11. The pressure sensor 13 samples the primary pressure at a predetermined cycle (for example, every 4 seconds). The sampled primary pressure data is converted into a digital signal by an A / D converter 21 provided in the governor chamber unit 20 and stored in a register of the CPU 22.

  The valve opening meter 14 is a so-called potentiometer, and the valve opening (specifically, a resistance value that varies depending on the valve opening) of the pressure regulator provided in the pressure regulator 11 is set to a predetermined period (for example, Sampling every 4 seconds). The sampled valve opening data is converted into a digital signal by an A / D converter 21 provided in the governor chamber unit 20 and stored in a register of the CPU 22. The valve opening meter 14 detects the valve opening as a substitute value for the gas flow rate, and thus corresponds to the “flow rate detecting means” of the present invention.

  The CPU 22 retrieves the maximum and minimum values from the 45 primary pressure and valve opening detection data sampled in 3 minutes, and stores the maximum and minimum values together with the date and time of occurrence in a register. Remember. The data of the maximum value and the minimum value is transferred to an SRAM (Static Random Access Memory) 23 every predetermined time. In the present embodiment, the maximum value and minimum value data are written to the SRAM 23 every 12 minutes.

  In the SRAM 23, the latest two weeks of detection data of the primary pressure and the valve opening can be accumulated together with the detection date and time. In addition to the SRAM 23, the governor room unit 20 is provided with a backup EEPROM 25, in which detection data for the last three days can be stored together with the detection date and time.

  The primary pressure and valve detection data accumulated in the SRAM 23 are transferred to the governor monitoring computer 50 in response to a request from the governor monitoring computer 50. The governor monitoring computer 50 stores the detection data of the primary pressure and the valve opening degree in a storage device, and can display it on a monitor as a graph as shown in FIGS. 5 (A) and 5 (B). In other words, the governor monitoring computer 50 has a load survey function for collecting and storing each detection data of the primary pressure and the valve opening in the pressure regulators 11 distributed and installed in various places of the city gas supply network.

  Here, in this embodiment, an auxiliary operation command computer 55 is provided in case the public PHS line goes down and communication between the governor monitoring computer 50 and each governor room unit 20 becomes impossible. Yes. The auxiliary operation command computer 55 is a portable so-called mobile personal computer, and is connected to a PHS terminal (not shown) in the vicinity of the governor room 10 (specifically, within a radius of about 50 m from the PHS module 24). Thus, communication with the governor room unit 20 is possible. Specifically, the PHS module 24 provided in the governor room unit 20 has an emergency transceiver mode in addition to the public line mode for communicating with the governor monitoring computer 50 through the public PHS line. The operation can be switched to any mode by operating the switch 26. When the public PHS line goes down, an attendant carries the auxiliary operation command computer 55 and goes to the governor room 10, and the PHS module 24 is switched to the transceiver mode locally, so that the transceiver mode is also set. It becomes possible to communicate with the auxiliary operation command computer 55 via the PHS terminal.

  Similarly to the governor monitoring computer 50, the auxiliary operation command computer 55 also obtains primary pressure and valve opening detection data from the governor chamber unit 20 (SRAM 23) and stores them in the storage device. Further, the valve opening degree detection data is compared with a reference allowable range for each time zone stored in advance in the built-in memory (ROM) of the auxiliary operation command computer 55 to make an abnormality determination. And when it determines with it being abnormal, a pressure regulator stop signal is output with respect to the governor chamber unit 20, and the emergency cutoff device 12 is operated. In this way, if the public PHS line goes down, each detection data can be collected at the site where the governor room 10 is located, and whether or not an abnormality has occurred can be determined. 12 can be activated. The auxiliary operation command computer 55 corresponds to “auxiliary operation command means” of the present invention.

  Next, operation | movement of the gas interruption | blocking system 100 of this embodiment is demonstrated in detail, referring the flowchart of FIG.3 and FIG.4.

  The governor monitoring computer 50 normally collects and stores detection data from a plurality of governor room units 20 installed at various locations in the city gas supply network at a predetermined time once a day, and further detects the detection data. An abnormality is determined based on the above. These processes are executed in accordance with the normal-time cutoff determination program PG1 shown in FIG.

  In the normal shutdown determination program PG1, first, it is determined whether or not a preset center polling time (time for requesting data transmission to the governor room unit 20) is reached (S1). When it is the center polling time (YES in S1), the data transmission is sequentially requested to the plurality of governor room units 20 to be monitored. Then, the latest detection data of the primary pressure and valve opening for the first day stored in the SRAM 23 of each governor room unit 20 is transmitted to the governor monitoring computer 50 through the public PHS line. The governor monitoring computer 50 stores these detection data in the storage device separately for each governor room unit 20 (regional block) as a transmission source (S2). Next, of the detection data collected from each governor chamber unit 20, it is determined whether or not the detection data of the valve opening is out of the reference allowable range corresponding to the regional block in which the governor chamber unit 20 is provided. It is determined whether or not an abnormality has occurred in the regional block (S3). Then, when no occurrence of abnormality is found in all the regional blocks where the governor chamber unit 20 (the governor chamber 10) is provided (the detection data of the valve opening does not deviate from the reference allowable range) (NO in S3). Immediately exits the normal interruption determination program PG1.

  Although not shown, the normal shut-off determination program PG1 updates the reference allowable range stored in the memory (ROM) for each time zone based on the latest one day of valve opening degree detection data acquired at this time. And set. This processing corresponds to “reference allowable range setting means” in the present invention. Thereby, even if the usage-amount of the gas in the downstream of the pressure regulator 11 (governor chamber 10) changes with a user's increase / decrease or a seasonal change, the reference | standard tolerance | permissible_range according to it is set automatically.

  On the other hand, if the occurrence of an abnormality is recognized in any of the regional blocks where the governor chamber 10 is provided (the detection data of the valve opening deviates from the reference allowable range) (YES in S3), the abnormality occurrence is determined by the administrator. In order to notify the user, a message is displayed on the monitor of the governor monitoring computer 50 (S4), a patrol light or buzzer (not shown) provided in the centralized monitoring center 51 is operated (S5), and a printer (not shown). A message is printed (S6), and an e-mail is transmitted to the e-mail address of a mobile phone or personal computer registered in advance (S7). Then, a pressure regulator stop signal is selectively output to the governor chamber unit 20 in the area block where the occurrence of abnormality is recognized (S8). In response to this, the emergency shut-off device 12 operates in the governor chamber 10, and the gas supply to the downstream side of the pressure regulator 11, that is, the regional block where the abnormality has occurred is stopped.

  Now, when an earthquake occurs in the city gas supply area or in the vicinity thereof, the seismometer 15 provided in the governor room 10 in each place detects the vibration caused by the earthquake. When the seismometer 15 detects a vibration corresponding to the reference seismic intensity or more, an alarm signal is output from the governor room unit 20 provided in the governor room 10 to the governor monitoring computer 50. Then, the governor monitoring computer 50 performs various processes in accordance with the earthquake interruption determination program PG2 shown in FIG.

  That is, when an alarm signal is received (YES in S11), a message stating that “an earthquake greater than the reference seismic intensity has occurred” is first displayed on the monitor of the governor monitoring computer 50 or a printer (not shown) provided in the central monitoring center 51. Output (S12). Next, data transmission is sequentially requested to one or a plurality of governor room units 20 that are the transmission source of the alarm signal. At this time, the governor monitoring computer 50 acquires each detection data of the gas primary pressure and the valve opening detected for a predetermined period before and after the alarm signal is transmitted and received (or before and after the seismometer 15 detects the vibration). To do. Of these detection data, the detection data of the valve opening is compared with the reference allowable range in the same time zone, and the occurrence of an abnormality in the area block where the governor room unit 20 (governor room 10) that sent the alarm signal is located. The presence or absence is discriminated (S14).

  Here, although an earthquake exceeding the reference seismic intensity was detected by the seismometer 15, no gas leakage occurred in the area block where it was detected, and the shutoff valve of the gas meter provided at the end of the city gas supply network did not operate In addition, when most gas users do not close the gas plug, the change in the flow rate of the gas flowing through the pressure regulator 11 is not different from the normal time, so the change in the valve opening of the pressure regulator 11 is also normal. The detection data of the valve opening is within the reference allowable range throughout the entire period. In such a case, it is determined that there is no abnormality (NO in S14), and the emergency shutdown device 12 is immediately exited without operating the emergency shutdown device 12. In other words, if the valve opening (gas flow rate) of the pressure regulator 11 is an earthquake that is almost the same as that in normal times or a vibration that travels on the ground due to a factor other than an earthquake, a disaster caused by gas does not occur. Continue to supply gas. Thereby, unnecessary gas cutoff is not performed, and the convenience of the user of gas can be improved.

  On the other hand, when a gas leak occurs in any of the regional blocks where the governor chamber 10 is provided due to the earthquake, the flow rate of the gas flowing through the pressure regulator 11 of the regional block increases dramatically compared to the normal time. In conjunction with this, the valve opening of the pressure regulator 11 becomes larger than normal and becomes equal to or higher than the upper limit of the reference allowable range.

  In addition, the gas flowing through the pressure regulator 11 when the shut-off valve is operated by many gas meters provided at the end of the city gas supply network due to an earthquake or when many gas users close the gas plugs. The flow rate of the pressure regulator 11 is drastically reduced compared to the normal time, and in conjunction with this, the valve opening of the pressure regulator 11 becomes smaller than the normal time, and becomes below the lower limit of the reference allowable range.

  In such a case, it is determined that an abnormality has occurred (YES in S14), and the same output processing (S15 to S18) as the above-described normal-time interruption determination program PG1 is performed, and there is an area where an abnormality has been recognized. A pressure regulator stop signal is output to the governor chamber unit 20 (S19). In response to this, the emergency shut-off device 12 operates in the governor chamber 10, and the gas supply to the downstream side of the pressure regulator 11, that is, the regional block where the abnormality has occurred is stopped. Thereby, at the time of gas leakage accompanying the occurrence of an earthquake, the occurrence of a disaster caused by gas can be prevented. In addition, when an earthquake of a scale that could cause a disaster occurs, the gas meter shutoff valve or gas stopper is shut off and the gas supply to the end is shut off, thereby preventing a disaster caused by the gas. .

  The process of step S14 in the earthquake interruption determination program PG2 corresponds to the “flow rate abnormality detecting means” in the present invention, and the process of step S19 corresponds to the “interruption operation command means” in the present invention.

  Thus, according to the present embodiment, it is a necessary condition that both an earthquake having a reference seismic intensity or higher and an abnormality in the valve opening of the pressure regulator 11 linked to the gas flow rate flowing through the pressure regulator 11 have occurred. Since the emergency shut-off device 12 is operated, unnecessary operation (stop of gas supply) of the emergency shut-off device 12 can be prevented. Further, even when an earthquake actually occurs, the emergency shut-off device 12 can be operated only for an earthquake of a scale that may cause a disaster, so that safety is ensured while improving convenience for gas users. be able to. And since the emergency cutoff device 12 is provided in the governor room 10 installed for every regional block of a city gas supply area, the disaster resulting from gas can be prevented in the wide range for every regional block.

  Further, since the governor monitoring computer 50 acquires the detection data of the primary pressure and the valve opening degree of the gas from each governor room unit 20 through the public PHS line, it is efficient to collect the detection data from each governor room 10. And can be done quickly. In addition, since each detection data can be recorded as electronic data on a hard disk or various recording media (MO, USB memory, etc.), it is possible to eliminate a space for storing a document in which the detection data is stored as in the prior art. Furthermore, it becomes easy to search and browse the detected data.

[Second Embodiment]
This second embodiment is an emergency shut-off on the condition that both an earthquake exceeding the reference seismic intensity and an abnormality in the valve opening, or both an earthquake exceeding the reference seismic intensity and an abnormality in the primary pressure of the gas have occurred. The device 12 is activated, which is different from the first embodiment.

  Specifically, in the memory (ROM) of the governor monitoring computer 50, the reference allowable range of the primary pressure of gas is stored together with the reference allowable range of the valve opening, and the cutoff judgment program PG2 during earthquake (FIG. 4). In the abnormality determination process (S14), the primary pressure abnormality is also determined together with the valve opening. When either the valve opening or the primary pressure is out of the reference allowable range (YES in S14), the emergency shut-off device 12 is activated (S19). Here, the pressure sensor 13 corresponds to the “primary pressure detection means” of the present invention, and step S14 corresponds to the “pressure abnormality detection means”.

  According to the present embodiment, the same effects as those of the first embodiment can be obtained, and even when either the valve opening meter 14 or the pressure sensor 13 is lost, an earthquake having a reference seismic intensity or more has occurred. Abnormality determination can be performed reliably, and the emergency shut-off device 12 can be operated based on the result.

[Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

  (1) In the above embodiment, the seismometer 15 is provided as the seismometer according to the present invention, but an SI sensor may be used. Moreover, you may provide both the seismometer 15 and SI sensor.

  (2) In the case where communication with the governor monitoring computer 50 is disabled due to the down of the public PHS line or the malfunction of the PHS module 24, the governor monitoring computer is equipped with the governor room unit 20 provided in the governor room 10. An abnormality determination similar to 50 may be performed. Specifically, in the EEPROM 25 of each governor chamber unit 20, the reference allowable range of the valve opening of the pressure regulator 11, and the same assistance as the normal interruption determination program PG1 and the earthquake interruption determination program PG2 exemplified in the above embodiment are provided. The interruption determination program is stored (see FIG. 2), and when communication is disabled, the CPU 22 reads out and executes the auxiliary interruption determination program from the EEPROM 25, and when it is determined as abnormal, the emergency interruption device 12 May be operated. In this configuration, the CPU 22 corresponds to the “auxiliary monitoring computer” of the present invention, and the CPU 22 functions as the “flow rate abnormality detecting means” and the “auxiliary operation command means” of the present invention by executing the auxiliary shutoff determination program. .

  Here, when the response to the data transmission to the governor monitoring computer 50 is not sent from the governor monitoring computer 50, the governor room unit 20 transmits, for example, an alarm signal but a signal requesting data transmission. May be switched from the abnormality determination by the governor monitoring computer 50 to the abnormality determination by the CPU 22 of the governor room unit 20.

  Alternatively, when data transmission to the governor monitoring computer 50 fails, it is configured to continuously perform retry transmission at intervals of 2 to 3 minutes, and when the number of consecutive retry transmission failures reaches the upper limit, the governor The abnormality determination by the monitoring computer 50 may be switched to the abnormality determination by the CPU 22 of the governor room unit 20.

  Note that the reference allowable range of the valve opening of the pressure regulator 11 stored in the EEPROM 25 of the governor chamber unit 20 can be set by data transmission from the governor monitoring computer 50 when communication is normal. preferable.

  (3) In the above embodiment, the primary pressure of the pressure regulator 11 detected by the pressure sensor 13 of each governor chamber 10 and the valve opening of the pressure regulator 11 detected by the valve opening meter 14 are used for governor monitoring. The computer 50 is configured to store the data as load survey data. However, the flow meter for detecting the flow rate of the gas flowing through the pressure regulator 11 or the throttle unit provided on the upstream side (or downstream side) of the pressure regulator 11 is used. A differential pressure gauge or the like for detecting the differential pressure before and after the gas may be provided, and the flow rate and differential pressure of these gases may be stored in the governor monitoring computer 50 as load survey data. Here, the gas flow rate may be obtained by an arithmetic expression from the valve opening of the pressure regulator 11 and the primary pressure upstream of the pressure regulator 11.

  (4) In the first embodiment, abnormality determination is performed based on the valve opening of the pressure regulator 11, but abnormality determination is performed based on detection data of the gas flow rate instead of the valve opening. Alternatively, the abnormality determination may be performed based on differential pressure detection data detected by a differential pressure gauge provided on the upstream side (or downstream side) of the pressure regulator 11 (see FIG. 2). .

  (5) The data communication network for performing communication between the governor room unit 20 and the governor monitoring computer 50 is preferably a public PHS line in that it is difficult for communication restrictions to be imposed in the event of a disaster. Here, when an earthquake occurs, a plurality of governor room units 20 are expected to transmit alarm signals to the governor monitoring computer 50 all at once. Therefore, when transmitting / receiving alarm signals, it is preferable to adopt a packet system in order to avoid center busy so that a plurality of alarm signals can be received simultaneously. On the other hand, when the governor monitoring computer requests the governor room unit 20 to transmit detection data (at the time of center polling), the circuit switching method, specifically, the PIAFS (Personal Handyphone System Internet Access Forum Standard) method is adopted. May be.

  The data communication network is not limited to the public PHS line, but may be another public telephone line or the Internet. Furthermore, the present invention is not limited to wireless communication, and may be wired communication or a combination of wireless communication and wired communication.

  (6) The second auxiliary operation that activates the emergency shut-off device 12 even if an abnormal gas flow rate or valve opening abnormality does not occur when the earthquake that has occurred is greater than or equal to the giant earthquake reference seismic intensity greater than the reference seismic intensity The command means may be provided in the governor monitoring computer 50 or the governor room unit 20. In this way, when a huge earthquake with a high probability of occurrence of a disaster occurs, it is possible to reliably operate the emergency cutoff device 12 and prevent a disaster caused by gas.

( 7 ) In the above embodiment, the emergency shutoff device 12 is configured to operate the pressure regulating valve of the pressure regulator 11. However, an emergency shutoff valve is provided in each governor chamber 10 separately from the pressure regulator 11, The supply of gas may be stopped by operating the emergency shut-off valve.

The conceptual diagram of the gas interruption | blocking system which concerns on one Embodiment of this invention Governor unit block diagram Flow chart of normal shutdown judgment program Flow chart of earthquake interruption judgment program (A) Graph showing transition of primary pressure, (B) Graph showing transition of valve opening

Explanation of symbols

10 governor room 11 pressure regulator 12 emergency shut-off device 13 pressure sensor 14 valve opening meter 15 seismometer 20 governor room unit 24 PHS module (data communication terminal)
50 Governor monitoring computer (pressure regulator monitoring computer)
51 Central Monitoring Center 55 Computer for Auxiliary Operation Command (Auxiliary Operation Command Means)
100 Gas cutoff system PG1 Normal shutdown judgment program (shutoff judgment program)
PG2 Earthquake interruption judgment program (interruption judgment program)

Claims (11)

Provided in the governor chamber in the middle of the gas supply path, an emergency shut-off device is provided in the pressure regulator for adjusting the gas pressure, and the emergency shut-off device is operated as necessary to the downstream of the pressure regulator. In the gas shut-off system that shuts off the gas supply,
A seismometer capable of detecting an earthquake exceeding a predetermined reference seismic intensity;
A flow rate detecting means capable of detecting a flow rate of gas flowing in the pressure regulator or a substitute value thereof;
It is determined that the flow rate of the gas or a substitute value thereof is equal to or higher than the upper limit value of the reference allowable range set in advance for each time zone , and that the flow rate is abnormal, and is equal to or lower than the lower limit value of the reference allowable range. A flow rate abnormality detecting means for determining the flow rate abnormality;
A gas shut-off system, comprising: an operation command means for actuating the emergency shut-off device on the condition that both an earthquake having the reference seismic intensity or higher and the flow rate abnormality have occurred.   2. The gas shutoff system according to claim 1, wherein the flow rate detecting unit detects a valve opening degree of a pressure regulating valve provided in the pressure regulator as a substitute value of the flow rate of the gas.   3. The gas cutoff system according to claim 1, wherein the flow rate detection unit detects a differential pressure before and after a throttle portion provided on the upstream side of the pressure regulator as a substitute value of the flow rate of the gas. A pressure regulator monitoring computer to which detection results of the seismometer and the flow rate detection means are input;
The gas cutoff system according to any one of claims 1 to 3, further comprising a cutoff judgment program for causing the pressure regulator monitoring computer to function as the flow rate abnormality detection means and the operation command means. The shut-off determination program stores the actual measurement value of the gas flow rate or a substitute value for each time zone in a normal time, and based on the stored data, the gas flow rate or the substitute value for each time zone. The pressure regulator monitoring computer functions as a reference tolerance setting means for updating and setting the reference tolerance of
The flow rate abnormality detecting means detects a flow rate abnormality when the flow rate of the gas or a substitute value thereof deviates from the reference allowable range for each time zone set by the reference allowable range setting means. Item 5. The gas shutoff system according to Item 4. The pressure regulator monitoring computer is disposed at a remote location away from the pressure regulator and connected between the pressure regulator and the pressure regulator monitoring computer via a data communication network,
A data communication terminal for transmitting and receiving a detection result of the seismometer and the flow rate detection means and an operation control signal to the emergency shut-off device between the pressure regulator and the pressure regulator monitoring computer, and the pressure regulator 6. The gas shutoff system according to claim 4, wherein the gas shutoff system is provided in the pressure regulator monitoring computer. The detection results of the seismometers and the flow rate detection means provided in the plurality of pressure regulators are processed by a single pressure regulator monitoring computer that functions as the flow rate abnormality detection means and the shutoff valve operation command means. The gas shut-off system according to claim 6, wherein the gas shut-off system is configured. The gas cutoff system according to claim 6 or 7, wherein the data communication network is a PHS line. When data transmission from the pressure regulator side to the pressure regulator monitoring computer is impossible, or a response to data transmission from the pressure regulator to the pressure regulator monitoring computer is sent from the pressure regulator monitoring computer to the pressure regulator. The gas cutoff system according to any one of claims 6 to 8, further comprising auxiliary operation command means for activating the emergency cutoff device when the emergency cutoff device is not sent. An auxiliary monitoring computer is provided on the pressure regulator side,
  10. The gas cutoff system according to claim 9, further comprising an auxiliary cutoff judgment program for causing the auxiliary monitoring computer to function as the flow rate abnormality detecting means and the auxiliary operation command means. A large earthquake reference seismic intensity greater than the reference seismic intensity was set, and when an earthquake greater than the huge earthquake reference seismic intensity was detected, the emergency shut-off device was activated even if the flow rate abnormality did not occur The gas shut-off system according to any one of claims 1 to 10, wherein