JPH10288337A - Gas shutting-off device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve safety in case an earthquake or the like occurs by a method wherein a supply of gas is stopped automatically or leakage of gas is checked. SOLUTION: This device is operated such that when an earthquake or the like is detected by an external sensor means 15, a shutting-off means 8 is operated by a shutting-off judging means 16 and even if gas is not used, supplying of gas from an LP container is stopped. After this operation, when a stopped condition of the earthquake or the like is detected by the external sensor means 15, the shutting-off means 8 is automatically recovered by a returning means 17. In addition, a leakage timer means 19 is started to operate, the leakage judging means 18 checks whether or not leakage occurs with a signal flowed from a flow rate sensing means 12 so as to judge that it is in a state in which the gas under non-detected flow rate of leakage can be used. In addition, when the flow rate of leakage is detected, it is judged that a stopping of gas equipment is forgotten and the shutting-off means 8 is operated to get a shut-off state of it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shut-off device for stopping a gas supply, performing a leak judgment and then returning when an abnormality such as an earthquake occurs in the supply of propane gas or the like.

[0002]

2. Description of the Related Art Conventionally, a gas shut-off device of this type has a configuration shown in FIG. 8 as disclosed in, for example, Japanese Patent Publication No. 1-37627.

[0005] In FIG. 8, reference numeral 1 denotes a control unit, which comprises a power supply control unit 2, a storage unit 3, and a cutoff determination unit 4. A switch circuit 5 is turned on / off by the power supply control unit 2. Reference numeral 6 denotes an abnormal sensor, for example, an earthquake sensor for detecting an earthquake.

When a signal from the abnormality sensor 6 matches a shutdown determination condition stored in the storage unit 3 in advance, the shutdown determination unit 4 outputs a shutdown to the driver unit 7. Reference numeral 8 denotes a shut-off valve, which operates when receiving a signal from the driver unit 7 and stops the supply of gas.

Usually, power is supplied from the control unit 1 to the abnormality sensor 6 via the switch circuit 5. When the abnormality sensor 6 detects an earthquake, a signal is output to the cutoff determining unit 4. When the cutoff condition matches the cutoff condition stored in advance, the cutoff valve 8 is operated.

[0006]

However, in the above-mentioned conventional configuration, when an abnormality is detected and cut off, a person must be dispatched to confirm and return, which is inconvenient.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to provide a gas shut-off device for automatically judging whether or not it is normal after an earthquake is detected.

[0008]

In order to achieve the above object, the present invention provides a flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, the flow rate detecting means and the external sensor means. A shut-off determining means for judging whether or not there is an abnormality from the output signal of the above, and outputting a shut-off signal at the time of an abnormal condition; a shut-off means for shutting off the supply of gas; and automatically resetting the shut-off means upon detecting a signal stop from the external sensor means. A return means for resetting, a leak determination means for determining whether or not the gas appliance is in a stopped state after the return by a flow signal and shutting off and outputting at the time of leakage, and a leak timer means for adjusting the leak determination time. As a result, if there is no leakage, a normal gas can be used, and if leakage is detected, the gas is shut off again.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, and an abnormality is determined based on output signals of the flow rate detecting means and the external sensor means. Shut-off determining means for outputting a shut-off signal, shut-off means for shutting off gas supply, reset means for automatically resetting the shut-off means upon detection of a signal stop from the external sensor means, and a gas appliance in a stopped state after reset. It is composed of a leak determining means for determining whether the leakage is detected by a flow rate signal and outputting a cutoff at the time of leak, and a leak timer means capable of adjusting the leak determining time. As a result, the earthquake is detected by the external sensor means, and the shut-off means is operated and cut off by the cut-off determination means. Thereafter, when the external sensor detects that the earthquake has stopped, the return is automatically performed by the recovering means, and a leak determination is made as to whether there is a flow signal. If there is no leakage, the normal gas can be used, and if leakage is detected, it is shut off again. This greatly enhances usability.

Also, a flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, a pressure detecting means for detecting a pressure of gas, an output signal of the flow rate detecting means and an output signal of the external sensor means Shut-off determining means for determining whether or not there is an abnormality and outputting a shut-off signal at the time of an error, shut-off means for shutting off gas supply, and reset means for automatically resetting the shut-off means upon detection of a signal stop from the external sensor means. A pressure change gradient detecting means for detecting a pressure change from a signal of the pressure detecting means, and a leak determining means for judging whether or not the gas appliance is in a stopped state after the return by the pressure signal of the pressure change gradient detecting means and outputting a cutoff at the time of leakage. It is composed of
As a result, the earthquake is detected by the external sensor means, and the shut-off means is operated and cut off by the cut-off determination means. After that, when the external sensor detects that the earthquake has stopped, the return is automatically performed by the recovering means, and the pressure is detected by the pressure detecting means to determine the leak. If the change gradient of the measured pressure value is equal to or less than a predetermined value, no gas is leaked and a normal gas operable state is set. This greatly improves safety and usability.

A flow rate detecting means for detecting a gas flow rate; an external sensor means for detecting an abnormality such as an earthquake; an output signal from the flow rate detecting means and the external sensor means; A shutoff determining unit that outputs a signal, a shutoff unit that shuts off gas supply, a resetting unit that automatically resets the shutoff unit when a signal stop from the external sensor unit is detected, and determines whether the gas appliance is in a stopped state after resetting. Leakage determination means that determines based on the flow signal and shuts off at the time of leakage, and leakage timer means that can adjust the leakage determination time,
It is constituted by retry means for automatically returning again after a predetermined time and determining leakage. As a result, the earthquake is detected by the external sensor means, and the shut-off means is operated and cut off by the cut-off determination means. Thereafter, when the external sensor detects that the earthquake has stopped, the return is automatically performed by the recovering means, and a leak determination is made as to whether there is a flow signal. If a leak is detected, it is shut off again, but after a certain period of time, the shut-off means is returned again by the return means to check for leakage. If there is no leakage, make the gas usable. This greatly improves safety and usability.

Further, a flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, a pressure detecting means for detecting a gas pressure, and an output signal of the flow rate detecting means and the external sensor means Shut-off determining means for determining whether or not there is an abnormality and outputting a shut-off signal at the time of an error, shut-off means for shutting off gas supply, and reset means for automatically resetting the shut-off means upon detection of a signal stop from the external sensor means. A pressure change gradient detecting means for detecting a pressure change from a signal of the pressure detecting means, a monitoring timer means for detecting a pressure change for a certain period, and a pressure of the pressure change gradient detecting means for determining whether the gas appliance is in a stopped state after returning. And a leakage judging means for judging based on a signal and outputting a cutoff at the time of leakage. As a result, the earthquake is detected by the external sensor means, and the shut-off means is operated and cut off by the cut-off determination means. After that, when the external sensor detects that the earthquake has stopped, the return is automatically performed by the recovering means, and the pressure is detected by the pressure detecting means to determine the leak. If the change gradient of the detected pressure value is equal to or more than a predetermined value for a certain period of time, it is determined to be a leak and cut off. If the change gradient of the measured pressure value is equal to or less than a predetermined value, it is determined that there is no leakage, and the normal gas usable state is returned. This greatly improves safety and usability.

Further, a flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, a pressure detecting means for detecting a pressure of gas, an output signal of the flow rate detecting means and the output signal of the external sensor means Shut-off determining means for determining whether or not there is an abnormality and outputting a shut-off signal at the time of an error, shut-off means for shutting off gas supply, and reset means for automatically resetting the shut-off means upon detection of a signal stop from the external sensor means. A pressure change gradient detecting means for detecting a pressure change from a signal of the pressure detecting means, and a leak determining means for judging whether or not the gas appliance is in a stopped state after the return by the pressure signal of the pressure change gradient detecting means and outputting a cutoff at the time of leakage. And retry means for automatically returning again after a predetermined time and determining leakage. As a result, the earthquake is detected by the external sensor means, and the shut-off means is operated and cut off by the cut-off determination means. After that, when the external sensor detects that the earthquake has stopped, the return is automatically performed by the recovering means, and the pressure is detected by the pressure detecting means to determine the leak. If the change gradient of the detected pressure value is equal to or more than a predetermined value for a certain period of time, it is determined to be a leak and cut off. After a predetermined time, the pressure is returned by the return means again, and the pressure value is detected.
If the change gradient of the measured pressure value is equal to or less than a predetermined value, it is determined that there is no leakage, and the normal gas usable state is returned. This greatly improves safety and usability.

(Embodiment 1) A first embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, components having the same functions as those in FIG. 8 are denoted by the same reference numerals. FIG. 1 is a system diagram of the gas shut-off device of the present invention.

In FIG. 1, reference numeral 9 denotes an LP container for supplying propane gas. A pipe 10 connects the LP container to the gas meter 12 via a regulator. Further, the gas meter 12 is connected to household appliances such as a water heater, a stove, a gas table, and the like via a pipe 10. Inside the gas meter 12, a flow detecting means 12 for measuring a gas flow rate, and a pressure detecting means 13
Are input to the control means 14.

FIG. 2 is a control block diagram showing a first embodiment of the control means 14. Reference numeral 15 denotes external sensor means for detecting, for example, earthquake detection, gas leakage, and the like. Reference numeral 16 denotes a cutoff determination unit. The signals from the flow determination unit 16a and the external sensor unit 15 that determine whether the value detected by the flow detection unit 12 is in accordance with the condition of the storage unit 3 storing the cutoff condition are stored in the storage unit 3. An abnormality determining unit 16b for determining whether or not the condition is a cutoff condition. Reference numeral 17 denotes a resetting means, which automatically resets the shutoff means 8 when a stop signal from the external sensor means 15 is detected when the external sensor means 15 shuts off. 18 is a leak determination means,
After the automatic return by the return means 17, the flow rate detecting means 1
In Step 2, check for gas leakage. 19 is a leak timer means for setting a time which can be measured up to an ignition flow area longer than the normal return safety confirmation time. It can be set by means such as communication.

Next, the operation of the above configuration will be described. When an earthquake or the like is detected by the external sensor means 15, the cutoff determination means 16
To operate the shut-off means 8 and L even if no gas is used.
The supply of gas from the P container is stopped. After that, when the earthquake or the like subsides and the stop state is detected by the external sensor means 15,
The return unit 17 automatically returns the shut-off unit 8. At the same time, the leak timer means 17 is started and the leak determination means 1
Reference numeral 8 checks a signal from the flow rate detecting means 12 for any leakage. If the leak determining means 18 does not detect the leak flow rate, it determines that the gas can be used. If the leak flow rate is detected, it is determined that the gas appliance has been forgotten to be stopped, and the shutoff means 8 is operated to shut off (see FIG. 3).

When an abnormal state such as an earthquake is detected in this manner, particularly in the case of a large earthquake, etc., it is difficult for humans to stop using the equipment. By performing automatic return and checking for leaks, any minute flow rate leak can be reliably detected, safety is improved, and the recovery operation can be performed automatically, improving usability.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 4, FIG. 2, FIG.
The components having the same functions as those described above are denoted by the same reference numerals.

FIG. 4 is a control block diagram showing a second embodiment of the control means 14. 20 is a pressure detecting means for detecting the pressure in the gas pipe. Reference numeral 21 denotes a pressure change gradient detecting means for obtaining a change gradient (change rate) of a pressure detection value by the pressure detecting means 20.

Next, the operation of the above configuration will be described. When an earthquake or the like is detected by the external sensor means 15, the cutoff determination means 16
To operate the shut-off means 8 to stop the gas supply even if the gas is not used. Thereafter, when the earthquake or the like subsides and the stopped state is detected by the external sensor means 15, the shut-off means 8 is automatically returned by the return means 17. Next, the pressure detecting means 20
To detect the pressure in the pipe 10. From the detected pressure value, the pressure change gradient detecting means 21 calculates a change gradient (pressure difference) of the pressure value. Based on the obtained pressure difference, the leak determination means 19 checks whether or not there is a leak. Pressure change gradient,
Alternatively, if the pressure difference is equal to or less than a predetermined value, it is determined that the gas can be used. On the other hand, if the pressure change gradient (or the pressure difference) is equal to or greater than the predetermined value, it is determined that there is a leak, that is, it is determined that the gas appliance has been forgotten to be stopped, and the shutoff means 8 is operated to shut off.

When an abnormal state such as an earthquake is detected in this way, the gas supply is immediately stopped, and when the abnormal state is released, automatic recovery is performed and a leak check is performed. In addition, the safety is improved and the recovery operation can be performed automatically, so that the usability is improved.

(Embodiment 3) Next, Embodiment 3 of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 5, the components having the same functions as those in FIGS. 1, 2, 4, and 8 are denoted by the same reference numerals.

FIG. 5 is a control block diagram showing a third embodiment of the control means 14. Reference numeral 22 denotes a retry unit, which drives the return unit 17 after a certain period of time when the leakage determination unit 18 determines that there is a leak and shuts off.

Next, the operation of the above configuration will be described. When an earthquake or the like is detected by the external sensor means 15, the cutoff determination means 16
To operate the shut-off means 8 to stop the gas supply even if the gas is not used. Thereafter, when the earthquake or the like subsides and the stopped state is detected by the external sensor means 15, the shut-off means 8 is automatically returned by the return means 17. At the same time, the leak timer means 17 is started, and the leak determination means 18 checks whether there is any leak based on the signal from the flow rate detection means 12. If the leak determining means 18 does not detect the leak flow rate, it determines that the gas can be used. If the leakage flow rate is detected, it is determined that the gas appliance has been forgotten to be stopped, and the shutoff means 8 is operated to shut off. Also,
The leak determination unit 18 outputs a start signal to the retry unit 22. After a certain period of time, the retry means 22 activates the return means 17 again to open the cutoff means 8. In other words, if the user closes the gas appliance before the retry means 22 operates, no leakage is detected and the gas can be used immediately.

When an abnormal state such as an earthquake is detected in this way, the supply of gas is immediately stopped, and when the abnormal state is released, automatic recovery is performed and leakage is confirmed. In addition, the safety is improved and the recovery operation can be performed automatically, so that the usability is improved.

(Embodiment 4) Next, Embodiment 4 of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 6, components having the same functions as those in FIGS. 1, 2, 4, 5, and 8 are denoted by the same reference numerals.

FIG. 6 is a control block diagram showing a fourth embodiment of the control means 14. Reference numeral 23 denotes a monitoring timer means for obtaining a pressure change gradient from the pressure value detected by the pressure detection means 20 by the pressure change gradient detection means 21 to detect a change in pressure for a certain period, and set the period. Leak determination means 18
Then, it is determined whether or not there is a leak from the pressure change gradient and the output signal from the monitoring timer means 23.

Next, the operation of the above configuration will be described. When an earthquake or the like is detected by the external sensor means 15, the cutoff determination means 16
To operate the shut-off means 8 to stop the gas supply even if the gas is not used. Thereafter, when the earthquake or the like has subsided and the stop state is detected by the external sensor means 15, the shut-off means 8 is automatically returned by the return means 17 and the monitoring timer means 23 is started. You. Next, the pipe 1 is detected by the pressure detecting means 20.
Detect pressure in zero. From the detected pressure value, the pressure change gradient detecting means 21 calculates a change gradient (pressure difference) of the pressure value. The leak judging means 19 checks whether or not there is a leak from the obtained pressure difference, and the setting is repeatedly performed for the set period of the monitoring timer means 23. If the pressure change gradient or the pressure difference is equal to or less than a predetermined value, it is determined that the gas can be used. On the other hand, if the pressure change gradient (or the pressure difference) is equal to or greater than the predetermined value for a certain period of time, it is determined that there is a leak, that is, it is determined that the gas appliance has been forgotten to be stopped, and the shutoff means 8 is operated to shut off.

When an abnormal state such as an earthquake is detected in this way, the supply of gas is immediately stopped, and then, when the abnormal state is released, automatic recovery is performed and leakage is confirmed. In addition, the safety is improved and the recovery operation can be performed automatically, so that the usability is improved.

(Embodiment 5) Next, Embodiment 5 of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 7, components having the same functions as those in FIGS. 1, 2, 4, 5, 6, and 8 are denoted by the same reference numerals.

FIG. 7 is a control block diagram showing a fifth embodiment of the control means 14. Reference numeral 23 denotes a monitoring timer means for obtaining a pressure change gradient from the pressure value detected by the pressure detection means 20 by the pressure change gradient detection means 21 to detect a change in pressure for a certain period, and set the period. Leak determination means 18
Then, it is determined whether or not there is a leak from the pressure change gradient and the output signal from the monitoring timer means 23.

Next, the operation of the above configuration will be described. When an earthquake or the like is detected by the external sensor means 15, the cutoff determination means 16
To operate the shut-off means 8 to stop the gas supply even if the gas is not used. Thereafter, when the earthquake or the like has subsided and the stop state is detected by the external sensor means 15, the shut-off means 8 is automatically returned by the return means 17 and the monitoring timer means 23 is started. You. Next, the pipe 1 is detected by the pressure detecting means 20.
Detect pressure in zero. From the detected pressure value, the pressure change gradient detecting means 21 calculates a change gradient (pressure difference) of the pressure value. The leak judging means 19 checks whether or not there is a leak from the obtained pressure difference, and the setting is repeatedly performed for the set period of the monitoring timer means 23. If the pressure change gradient or the pressure difference is equal to or less than a predetermined value, it is determined that the gas can be used. On the other hand, if the pressure change gradient (or the pressure difference) is equal to or greater than the predetermined value for a certain period of time, it is determined that there is a leak, that is, it is determined that the gas appliance has been forgotten to be stopped, and the shutoff means 8 is operated to shut off. Further, the leak determination unit 18 outputs an activation signal to the retry unit 22. After a certain period of time, the retry means 22 activates the return means 17 again to open the cutoff means 8. That is, retry means 2
If the user puts the gas appliance in a closed state before the operation of the gas detector 2, the leak detection is detected and the gas can be used immediately.

When an abnormal state such as an earthquake is detected in this way, the supply of gas is immediately stopped, and when the abnormal state is released, automatic recovery is performed and the leakage is checked with high accuracy. However, detection can be performed reliably, safety is improved, and the recovery operation can be performed automatically, so that usability is improved.

[0036]

As described above, according to the present invention, if an abnormal condition such as an earthquake is detected by an external sensor means, it is difficult for a person to take action to stop using the appliance, especially in the case of a large earthquake, so that the device is immediately shut off. When the gas supply is stopped by operating the means and the abnormal state is stopped by the external sensor means, the shut-off means is automatically returned by the return means and the flow detection means is used to check whether there is any leakage. Judgment for the above fixed period and if you forget to turn off the used equipment, shut off again,
If there is no leakage, it is determined that the gas can be used normally, so when an abnormality such as an earthquake occurs, humans can automatically judge the leak without running around to return operation and return to the state where gas can be used normally, so it is extremely safe This has the effect of increasing ease of use and improving usability.

Further, according to the present invention, when an abnormal state such as an earthquake is detected by the external sensor means, the shut-off means is immediately activated to stop the gas supply, and when the external sensor means detects that the abnormal state is stopped, The return means automatically returns the shut-off means, and the pressure detection means detects whether there is a leak based on the pressure change gradient.If there is no forgetting to turn off the used equipment, it is shut off again.If there is no leak, the gas can be used normally. When an abnormality such as an earthquake occurs, it is possible to automatically determine a leak without running around for a return operation and return to a state where gas can be used normally, so that there is an effect that safety is extremely enhanced and usability is improved. .

According to the present invention, when an abnormal state such as an earthquake is detected by the external sensor means, the shut-off means is immediately activated to stop the gas supply, and when the external sensor means detects that the abnormal state has been stopped. The return means automatically returns the shut-off means, and the flow rate detection means determines whether there is any leakage for a certain period of time longer than the normal return safety confirmation time.If the user forgets to turn off the used equipment, it shuts off again and then forgets to turn off the used equipment. Is released, re-automatically resumes by retry means to check for leaks.If there is no leak, it is judged that the gas can be used normally, and when an abnormality such as an earthquake occurs, the leak is automatically detected without running around to return operation. As a result, the gas can be returned to a state where it can be used normally, and thus the safety is extremely enhanced and the usability is improved.

According to the present invention, when an abnormal state such as an earthquake is detected by the external sensor means, the shut-off means is immediately activated to stop the gas supply, and when the external sensor means detects that the abnormal state has been stopped, The return means automatically returns the shut-off means, the pressure detection means detects whether there is a leak by the pressure change gradient, and if the use of the monitoring timer means that the used equipment has been continuously forgotten to be turned off for a certain period of time, it is shut off again. If there is no leakage, it is determined that the gas can be used normally.In the event of an abnormality such as an earthquake, humans can automatically judge the leak without running around to return operation and return to the state where gas can be used normally. This has the effect of increasing safety and improving usability.

Further, according to the present invention, when an abnormal condition such as an earthquake is detected by the external sensor means, the shut-off means is immediately activated to stop gas supply, and when the external sensor means detects that the abnormal state has stopped, The return means automatically returns the shut-off means, the pressure detection means detects whether there is a leak by the pressure change gradient, and if the use of the monitoring timer means that the used equipment has been continuously forgotten to be turned off for a certain period of time, it is shut off again. After that, if the user forgets to turn off the used equipment, it is automatically returned again by the retry means to check for leaks.If there is no leak, it is determined that the gas can be used normally, and when an abnormality such as an earthquake occurs, humans can perform the recovery operation Since the leak can be automatically determined without running around and the gas can be returned to a state where the gas can be used normally, the safety is extremely improved and the usability is improved.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a gas shut-off device of the present invention.

FIG. 2 is a control block diagram of the gas cutoff device according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing the operation of the apparatus.

FIG. 4 is a control block diagram of a gas cutoff device according to a second embodiment of the present invention.

FIG. 5 is a control block diagram of a gas shutoff device according to a third embodiment of the present invention.

FIG. 6 is a control block diagram of a gas shutoff device according to a fourth embodiment of the present invention.

FIG. 7 is a control block diagram of a gas shutoff device according to a fifth embodiment of the present invention.

FIG. 8 is a control block diagram of a conventional gas shut-off device.

[Explanation of symbols]

 Reference Signs List 8 shut-off means 12 flow rate detection means 15 external sensor means 17 return means 18 leak determination means 19 leak timer means 20 pressure detection means 21 pressure change gradient detection means 22 retry means 23 monitoring timer means

Claims (5)

[Claims] 1. A flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, and an output signal of the flow rate detecting means and the external sensor means for judging whether or not there is an abnormality, and shutting off in the event of an abnormality. Shutoff determination means for outputting a signal,
Shut-off means for shutting off gas supply; reset means for automatically resetting the shut-off means upon detection of a signal stop from the external sensor means; and determining whether the gas appliance is in a stopped state after the reset by the flow signal. And a leak timer means that can adjust the leak determination time. 2. A flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, a pressure detecting means for detecting a gas pressure, and an output signal of the flow rate detecting means and the external sensor means. Shut-off determining means for judging whether there is more abnormality and outputting a shut-off signal in the event of an abnormality, shut-off means for shutting off gas supply, and resetting means for automatically resetting the shut-off means when a signal stop from the external sensor means is detected. A pressure change gradient detecting means for detecting a pressure change based on a signal from the pressure detecting means, and a leak which outputs a shut-off signal in the event of a leak by judging whether or not the gas appliance is in a stopped state after return by the pressure signal of the pressure change gradient detecting means. A gas cutoff device comprising a determination unit. 3. A flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, and an output signal of the flow rate detecting means and the external sensor means for judging whether or not there is an abnormality, and shutting off in the event of an abnormality. Shutoff determination means for outputting a signal,
Shut-off means for shutting off gas supply; reset means for automatically resetting the shut-off means upon detection of a signal stop from the external sensor means; and determining whether the gas appliance is in a stopped state after the reset by the flow signal. A gas shut-off device comprising: a leak judging means for outputting a signal; a leak timer means capable of adjusting the leak judging time; and a retry means for automatically returning again after a predetermined time to make a leak judgment. 4. A flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, a pressure detecting means for detecting a gas pressure, and an output signal of the flow rate detecting means and the external sensor means. Shut-off determining means for judging whether there is more abnormality and outputting a shut-off signal in the event of an abnormality, shut-off means for shutting off gas supply, and resetting means for automatically resetting the shut-off means when a signal stop from the external sensor means is detected. A pressure change gradient detecting means for detecting a pressure change from a signal of the pressure detecting means, a monitoring timer means for detecting a pressure change for a certain period, and a pressure of the pressure change gradient detecting means for determining whether the gas appliance is in a stopped state after returning. A gas shut-off device comprising a leak judging means for judging by a signal and outputting a shut-off signal at the time of leakage. 5. A flow rate detecting means for detecting a gas flow rate, an external sensor means for detecting an abnormality such as an earthquake, a pressure detecting means for detecting a pressure of a gas, and an output signal of the flow rate detecting means and the external sensor means. Shut-off determining means for judging whether there is more abnormality and outputting a shut-off signal in the event of an abnormality, shut-off means for shutting off gas supply, and resetting means for automatically resetting the shut-off means when a signal stop from the external sensor means is detected. A pressure change gradient detecting means for detecting a pressure change based on a signal from the pressure detecting means, and a leak which outputs a shut-off signal in the event of a leak by judging whether or not the gas appliance is in a stopped state after return by the pressure signal of the pressure change gradient detecting means. A gas shut-off device comprising a judging means and a retry means for automatically returning again after a predetermined time to make a leak judgment.