JP2014232077A - Gas shut-off device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas shut-off device capable of confirming seismic signals within a predetermined time after detecting an earthquake and performing unrestorable gas shut-off at a timing in which the conditions such as a scale of an earthquake, local geological characteristics and the buildings are considered.SOLUTION: The gas shut-off device includes: a seismic sensor 12 that detects vibrations and outputs a seismic signal; a shutoff valve 14; and a controller 19 that controls the shutoff valve 14 to shut off the gas when determining an earthquake on the basis of the seismic signal. The controller 19 is configured to control the shutoff valve to, when detecting an earthquake, after performing an unrestorable gas shut-off operation, start measuring of a first predetermined time (waiting time); and after the first predetermined time has elapsed, start measuring of a second predetermined time. When no seismic signal is detected from the seismic sensor 12 during measuring the second predetermined time, the controller 19 controls the shutoff valve to switch the unrestorable gas shut-off to restorable gas shut-off to thereby restore the gas supply when a return switch is pressed or by an automatic restoration.

Description

  The present invention relates to a gas shut-off device that performs control so that gas can be used by depressing a return switch or automatically returning after shutting off an unrecoverable gas by detecting an earthquake.

  Conventionally, after a strong earthquake is detected and non-recoverable gas is shut off, measurement is started for a predetermined time, and if an event such as an earthquake is not detected during this time, the non-recoverable gas shut-off state can be restored. By changing to the state, the gas can be used by depressing the return switch or automatically returning (see, for example, Patent Document 1).

  FIG. 3 shows a configuration diagram of a conventional gas cutoff device described in Patent Document 1. As shown in FIG. As shown in FIG. 3, the gas meter 110 includes a flow sensor 111 that detects a gas flow rate, a seismic sensor 112 that outputs a seismic signal corresponding to the intensity of vibration caused by an earthquake, a pressure sensor 113 that detects a gas pressure, A shutoff valve 114 that shuts off the supply, a display unit 115 that displays gas usage, alarms, and other information, and a communication I / F (interface) connected to a remote monitoring center 121 via a telephone line (network) 120 116, a test switch 117 as a shut-off function inspection means for testing a gas shut-off function, a return switch 118 for opening the shut-off valve 114 when the gas is shut off, and a signal from the sensor or switch My controller that executes various arithmetic processes necessary for controlling the gas meter 110, such as controlling the shut-off valve 114 and the display unit 115. B computer includes a controller 119 as a control unit composed of a (not shown CPU, a memory, a timer, including input and output interfaces, etc.).

  After the seismic sensor 112 determines that the earthquake has occurred and shuts off the non-returnable gas, the predetermined time counting means 119a starts measuring a predetermined time, and the seismic sensor 112 detects that there is a vibration within this predetermined time. If it is not detected, automatic recovery is possible.

  For the gas meter 110, an operator connects the communication device 122 and the gas meter 110 with a connection cable (not shown), and transmits and receives necessary data to each other, thereby releasing the non-recoverable gas cutoff and plugging state. It is possible to transmit a return command for instructing opening of the shut-off valve 114, and set a shut-off condition, an operation mode and the like. Further, after the gas is shut off by the shutoff valve 114, an operation mode with / without automatic return, which is a mode for automatically opening the shutoff valve 114 if a predetermined condition is satisfied, can be set. These settings can also be performed by transmitting / receiving necessary data to / from the monitoring center 121 via the telephone line 120.

JP 2004-205333 A

  However, in the above-described conventional configuration, after determining that an earthquake has occurred and performing non-recoverable gas shut-off, the predetermined time counting means 119a starts measuring a predetermined time, and the seismic sensor 112 from the seismic sensor 112 within this predetermined time. Check the signal. For this reason, when the distance from the epicenter is close or large, or when the magnitude of the earthquake is small but the shaking time is long due to geological characteristics, the earthquake has not ended and the feeling within the specified time There was a problem in checking the seismic signal that it was determined again that there was an earthquake.

  That is, as shown in FIG. 4, after the first earthquake determination is performed at timing a, it is detected whether an earthquake has occurred within a predetermined time b.

  However, since the seismic detection signal is confirmed from the vibration detection means within a predetermined time after the timing “a” when the non-recoverable gas is shut off after judging the earthquake, the earthquake ends in the case of a large earthquake. However, it was determined again that there was an earthquake by checking the seismic signal within the prescribed time. For this reason, the confirmation of the seismic signal within a predetermined time was too early, and it was determined that the return was impossible without waiting for the end of the earthquake.

  The present invention solves the above-mentioned conventional problems. After performing a gas shut-off that is determined to be an earthquake and cannot be restored, the seismic signal at a timing that takes into account conditions such as the magnitude of the earthquake, regional characteristics of the geology, and buildings. An object of the present invention is to provide a gas cutoff device capable of confirming the above.

  In order to solve the above-described conventional problems, a gas shutoff device according to the present invention includes a flow rate sensor that measures a flow rate of a gas flowing in a flow path, a seismic sensor that detects a vibration and outputs a seismic signal, and the flow sensor. A shut-off valve that opens and closes the road, and a controller that judges the presence or absence of an earthquake from the seismic signal output from the seismic sensor, and shuts off gas by the shut-off valve when it is determined that there is an earthquake, After the controller determines that there is an earthquake and shuts off the non-recoverable gas, it starts counting the first predetermined time, and then starts measuring the second predetermined time after measuring the first predetermined time. When no seismic signal is detected from the seismic sensor during the second predetermined time, the non-recoverable gas shut-off state is changed to a recoverable gas shut-off state. In this way, control is performed so that the gas can be used by pressing the return switch or by automatic return.

  According to the present invention, it is possible to reduce the number of occurrences of non-recoverable interruptions due to an earthquake, and it is possible to reduce the number of unnecessary dispatches and burdens of gas companies.

Configuration diagram of gas shutoff device of the present invention Flowchart of the automatic return operation method of the present invention Configuration diagram of conventional gas shut-off device Diagram showing measurement timing using conventional seismic waveform The figure which shows the measurement timing using the seismic waveform when there is waiting time of this invention

  According to a first aspect of the present invention, there is provided a flow rate sensor that measures a flow rate of a gas flowing through a flow path, a seismic sensor that detects a vibration and outputs a seismic signal, a shut-off valve that opens and closes the flow path, and the seismic sensitivity. A controller that determines the presence or absence of an earthquake based on the seismic signal output from the sensor, and shuts off the gas using the shut-off valve when it is determined that there is an earthquake. After the gas is shut off, the time measurement of the first predetermined time is started. After the time measurement of the first predetermined time, the time measurement of the second predetermined time is started and the time measurement of the second predetermined time is started. When no seismic signal is detected from the seismic sensor, the gas cutoff device changes the non-recoverable gas cutoff state to the recoverable gas cutoff state. As a result, the gas can be used by pressing the return switch or automatically returning, the number of occurrences of non-recoverable interruptions can be reduced, and the number of operations and the burden on the gas company can be reduced.

  According to a second aspect of the invention, in particular, in the gas shutoff device of the first aspect of the present invention, the gas cutoff device includes an operation means operable from the outside or a communication means capable of communication with the outside, and the operation means receives a predetermined operation Alternatively, the first predetermined time can be changed from the outside by receiving a predetermined signal via the communication means. By setting the first predetermined time according to the magnitude and intensity of the earthquake, the geological characteristics, and the frequency of aftershocks, the presence or absence of the earthquake at the timing appropriate for the area where the meter is installed, even for the same earthquake Detection can be performed, and the occurrence of gas interruption that cannot be automatically restored can be minimized.

  In a third aspect of the invention, in particular, in the gas shutoff device of the first aspect of the invention, the seismic sensor outputs a seismic signal corresponding to the magnitude of the seismic motion, and the controller receives a seismic signal that is greater than or equal to a predetermined value. When it is determined that there is an earthquake of magnitude, non-returnable gas shut-off is performed, and the first predetermined time can be changed according to the magnitude of the earthquake. This makes it possible to respond to various earthquakes.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.
(Embodiment 1)
FIG. 1 shows a configuration diagram of a gas cutoff device in a first embodiment of the present invention.

  In FIG. 1, a gas meter 10 includes a flow sensor 11 that detects a gas flow rate, a seismic sensor 12 that outputs a seismic signal corresponding to the intensity of vibration caused by an earthquake, a pressure sensor 13 that detects a gas pressure, and shuts off gas supply. In order to test the shut-off valve 14, the display unit 15 for displaying gas usage, alarms, and other information, the communication I / F 16 connected to the remote monitoring center 21 via the telephone line 20, and the gas shut-off function A test switch 17 as a shut-off function inspection means, a return switch 18 for opening the shut-off valve 14 when the gas is shut off, and a microcomputer (not shown) for executing various arithmetic processes necessary for controlling the gas meter 10 And a controller 19 including a CPU, a memory, a timer, an input / output interface, and the like.

  In addition, when the worker connects the communication device 22 and the communication I / F (communication means) 16 of the gas meter 10 with a connection cable (not shown), necessary data is transmitted and received between the gas meter 10 and the communication device 22. it can. Therefore, by operating the communication device 22, it is possible to cancel the non-returnable shut-off state, send a return command for switching the shut-off valve 14 from the closed state to the open state, or set the shut-off condition, operation mode, etc. it can. For example, by inputting a predetermined signal via the communication I / F, a waiting time (first predetermined time) described later can be set with an arbitrary time width. These settings can also be performed by transmitting / receiving necessary data to / from the monitoring center 21 via the telephone line 20. Needless to say, the gas meter 10 itself may be provided with an operation switch (operation means) for setting a time and a predetermined operation is performed on the operation means.

  The shut-off valve 14 is installed in the middle of a gas flow path (not shown) piped in the gas meter 10. The shutoff valve 14 is used when an earthquake occurrence is detected by the seismic sensor 12, a gas flow rate detected by the flow sensor 11 is abnormal, or a gas pressure value detected by the pressure sensor 13 is an abnormal value. In addition, the gas is shut off based on an instruction from the controller 19.

  The gas shut-off state includes a recoverable gas shut-off state and a non-recoverable gas shut-off state. In the recoverable gas shut-off state, a return command is sent from the monitoring center 21 or the communication device 22 to the gas meter 10 or the return switch 18 is pressed, so that the gas can be used, that is, the shut-off valve 14 is opened. State.

  On the other hand, in the non-recoverable gas shut-off state, a non-recoverable release command is transmitted from the monitoring center 21 or the communication device 22 to the gas meter 10 so that the recoverable gas shut-off state is established. Thereafter, a return command is sent from the monitoring center 21 or the communication device 22 to the gas meter 10 or the return switch 18 is pressed, so that the gas can be used, that is, the shutoff valve 14 is opened. it can.

  The return switch 18 is a switch for returning the shut-off valve 14, which is closed and shuts off the gas, to a state in which it can be opened again and used. When the return switch 18 is pressed by a customer or worker, the controller 19 opens the shut-off valve 14 as a return process. Even when the return switch 18 is pressed in this manner, it can be considered that it is confirmed that it is safe even if the gas is used by a customer or the like.

  The controller 19 performs a process of calculating the amount of gas used and displaying it on the display unit 15. The controller 19 constantly monitors the gas flow rate or gas pressure abnormality, the occurrence of an earthquake, the power supply voltage, and the like through each sensor. When an abnormality is detected, the gas is shut off or alarmed, and a process for notifying the remote monitoring center 21 of the use state of the gas meter 10, the alarm content, etc. is executed as necessary.

  Further, the controller 19 may adopt the magnitude of the earthquake based on the seismic signal output from the seismic sensor 12 (for example, “the magnitude of the seismic intensity” representing the magnitude of the shaking as the “magnitude of the earthquake”). ). Here, if it is determined that the earthquake is less than a predetermined magnitude (weak earthquake), a recoverable gas cutoff is performed.

  On the other hand, if it is determined that the earthquake is greater than a predetermined magnitude (strong earthquake), a non-recoverable gas cutoff is performed. Then, after the first predetermined time (standby time) is measured by the standby time measuring means 19a, the second predetermined time is started to be measured by the detection time measuring means 19b.

  When no seismic signal is detected from the seismic sensor 12 within the second predetermined time, a gas shut-off process is performed to change the non-recoverable gas shut-off state to a recoverable gas shut-off state.

  Further, when the recoverable gas shutoff is performed, the controller 19 executes an automatic return process for automatically canceling the gas shutoff state. This automatic return is one of the functions provided in the existing gas meter, and is set to an operation mode with or without automatic return.

  Further, the controller 19 has a function of changing from the non-recoverable gas cutoff state to the recoverable gas cutoff state when the test cutoff is performed. This test cut-off means a cut-off by operating the test switch 17, is a cut-off with a higher priority of execution than a cut-off by an earthquake, and is a reversible cut-off. Accordingly, by performing the test interruption within the second predetermined time, it is possible to change from the non-recoverable interruption state to the recoverable interruption state.

  The test switch 17 is constituted by a reed switch, and the test interruption by the test switch 17 is performed by a worker having specialized skills. That is, the safety check after an earthquake or other abnormality occurs is carried out by an operator. Therefore, when a gas cutoff test is performed by the test switch 17, it can be considered that it is confirmed that it is safe to use gas by an operator.

  In the present embodiment, the method for determining whether or not the test is interrupted while measuring the second predetermined time (detection time) has been described. However, during the measurement of the first predetermined time (waiting time), or waiting. It can be done at any time after the time.

  Next, the operation and action of the gas shut-off device configured as described above will be described with reference to the flowchart of FIG.

  The process described below is executed by the microcomputer of the controller 19 according to a program.

  First, it is determined whether or not a gas is shut off (S101). If the gas is not shut off (S101: NO), the presence or absence of an earthquake is determined (S102).

  That is, the controller 19 constantly monitors the occurrence of earthquakes, abnormalities in the gas flow rate and gas pressure, etc., and when these abnormalities are detected, the shutoff valve 14 is closed and the gas can be shut off or cannot be restored. Turn off the gas. When the seismic signal is received from the seismic sensor 12 and the occurrence of an earthquake is detected, a non-recoverable shut-off is performed.

  If it is determined in step S102 that there is an earthquake (S102: YES), a non-recoverable gas shut-off state is set (S103), and counting of a first predetermined time (standby time) is started (S105). In addition, about the process of step S102, it may replace with only determining the presence or absence of an earthquake, and may determine the presence or absence of the "earthquake larger than a predetermined magnitude by a seismic signal."

  If a gas cutoff state is detected in step S101 (S101: YES), it is determined whether the detection time (second time measurement time) is being measured (S110). (S110: YES), the process proceeds to step S111.

  If it is determined in step S110 that the detection time (second time measurement) is not being measured (S110: NO), it is determined whether or not the standby time (first predetermined time) is being measured (S104). Is determined (S104: YES), it is determined whether the standby time has elapsed (S106).

  Next, when it is determined in step S106 that the standby time has elapsed (S106: YES), the timing of the second predetermined time (detection time) for redetecting the seismic signal after the interruption is started (S107). .

  If it is determined in step S110 that the detection time (second time measurement) is being measured (S110: YES), it is determined whether the detection time has elapsed (S111), and if the detection time has elapsed. (S111: YES), the state is changed to a recoverable gas shut-off state because an earthquake was not detected during the detection time (S113).

  If it is determined in step S111 that the detection time has not elapsed (S111: NO), it is determined whether the test is interrupted by operating the test switch 17 (S109), or the monitoring center 21 or the communication device 22 is determined. It is determined whether or not there has been a command to cancel the non-recoverable shut-off state (S114), and if there is a test shut-off (S109: YES) or there is a cancel command (S114: YES), it is determined that the recoverable gas is shut off. (S113).

  If there is neither a test interruption nor a release command, the presence / absence of an earthquake is determined (S108), and if it is determined that there is an earthquake (S108: YES), it cannot be recovered as an earthquake was detected during the detection time. It is determined that the gas has been shut off (S112).

  If it is determined that the gas can be restored (S113), the controller 19 changes the shutoff valve 14 to be managed as a recoverable gas cutoff state if it is managed as a non-recoverable gas cutoff state. Similarly, when the non-recoverable gas cutoff is determined (S112), if the controller 19 manages the shut-off valve 14 as a recoverable gas cutoff state, the controller 19 changes the management so that the non-recoverable gas cutoff state is managed.

  Further, although not described with reference to a flowchart, a process for opening the shutoff valve 14 in a recoverable gas shutoff state will be described below.

  First, it is determined whether or not a mode with automatic return is set, and if it is a mode with automatic return, a gas cutoff return process (opening of the cutoff valve 14) is performed. If the mode is a mode without automatic return, it is determined whether the return switch 18 has been pressed as a return operation.

  Hereinafter, the effect of the present embodiment will be described with reference to FIG.

  FIG. 5 shows a typical example of the relationship between the seismic waveform, the earthquake detection timing a, the standby time c, and the detection time d. As shown in FIG. 5, in this embodiment, when the first earthquake determination is performed at the timing a, whether or not an earthquake occurs within the detection time d after the subsequent standby time c has elapsed. Judgment is being made.

  Therefore, unlike the conventional determination method described with reference to FIG. 4, by using the standby time c set at an appropriate time, it is possible to wait for the end of the earthquake and perform the next earthquake determination.

  This makes it possible to determine that there is no earthquake at the time of the next earthquake judgment after making the non-recoverable gas shut-off state once at the first earthquake detection. Return processing or automatic return by pressing 18 is possible. Therefore, it is not necessary for the worker to transmit a release command via the communication device 22, and the number of times the worker is dispatched is reduced. Therefore, it is possible to save human expenses and time while ensuring safety.

  In the present embodiment, the second predetermined time (standby time) is one, but the magnitude of the earthquake is determined based on the detected seismic signal, and the controller 19 is based on the magnitude of the earthquake. The standby time may be set automatically. Needless to say, a plurality of waiting times may be stored in advance in a memory or the like, and the controller 19 may select according to the magnitude of the earthquake.

  As described above, the gas shut-off device according to the present invention detects an earthquake and performs non-recoverable gas shut-off. When not detected, the non-recoverable gas cutoff state is changed to a recoverable gas cutoff state. Such a gas shut-off device can also be applied to uses such as a water meter if the gas is replaced with water or the like.

11 Flow sensor 12 Seismic sensor 14 Shut-off valve 16 Communication I / F (communication means)
17 Test switch 18 Return switch 19 Controller

Claims (3)

A flow sensor for measuring the flow rate of the gas flowing through the flow path;
A seismic sensor that detects vibration and outputs a seismic signal;
A shut-off valve for opening and closing the flow path;
A controller that determines the presence or absence of an earthquake based on a seismic signal output from the seismic sensor, and shuts off gas by the shut-off valve when it is determined that there is an earthquake, and
The controller determines that there is an earthquake and shuts off the non-recoverable gas, then starts measuring the first predetermined time, and then starts measuring the second predetermined time after measuring the first predetermined time. When the seismic signal is not detected from the seismic sensor during the second predetermined time, the gas cutoff device changes the non-recoverable gas cutoff state to the recoverable gas cutoff state. Provided with an operation means that can be operated from the outside or a communication means that can communicate with the outside,
The configuration according to claim 1, wherein the first predetermined time can be changed from the outside by accepting a predetermined operation by the operation unit or receiving a predetermined signal through the communication unit. Gas shut-off device. The seismic sensor outputs a seismic signal corresponding to the magnitude of the vibration,
The controller performs non-returnable gas shut-off when it is determined by the seismic signal that there is an earthquake of a predetermined magnitude or greater, and the first predetermined time can be changed according to the magnitude of the earthquake. The gas cutoff device according to claim 1.

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