JP3334373B2 - Gas shut-off device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shut-off device for ensuring safety when using gas after a gas meter.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, this type of gas shut-off device monitors a flow rate signal X which outputs a flow rate signal X corresponding to a passing gas amount, and monitors the flow rate signal X for a specific period (3.
If the flow signal X constantly appears during the 0 day period), the flow signal monitoring unit 12 outputs the inner pipe leakage signal Y, and a warning is issued based on the inner pipe leakage signal Y of the flow signal monitoring unit 12 to shut off the gas passage. And an interruption notification unit 13.

[0003]

However, such a gas shut-off device requires a long monitoring period to confirm that the flow signal has been continuously generated for 30 days.
Even if a gas leak has occurred, it was not possible to immediately obtain an abnormal state.

[0004] That is, in the conventional gas shut-off device, there is a long dead period of at least 30 days despite the gas leakage, so that the gas leaks for an extremely long time, resulting in an unsafe condition. was there.

Therefore, the gas shut-off device of the present invention learns a period in which gas is not used, opens and closes a gas passage during a period in which the learned gas is not used, and determines whether or not the pressure in the confined gas passage has dropped. Automatically and for a short period (several hours)
The purpose is to detect gas leaks by detecting with.

[0006]

Means for Solving the Problems In order to achieve the above object, the present invention provides a flow measuring section for outputting a flow signal corresponding to the amount of passing gas, and a gas passage downstream from the apparatus. A shutoff unit, monitors the flow signal, detects and holds a non-flow time period in which no flow signal is present during a specific investigation period, and thereafter outputs a pressure test request signal when the flow becomes a no-time period. The learning unit and the non-flow rate time zone, and when the flow rate signal is not received, instructs the shut-off unit to shut off the gas passage, and the gas passage shut off by the pressure detection unit that detects a change in pressure is within a predetermined time. And a pressure test unit for detecting and instructing whether the pressure has dropped below a predetermined value.

[0007]

According to the above-mentioned means, the means of the present invention learns the gas usage pattern of the gas user and uses the time zone when the gas user is not using the gas so that the gas user cannot use the gas. Without inconvenience, the gas passage is shut off once, the gas pressure is automatically checked for a certain period of time (a few hours), and automatically before the gas user starts using the gas again. The gas passage can be opened.

In this way, the gas leak inspection can be performed automatically and in a short time, so that the soundness of the gas passage can be obtained at an early stage, and the abnormality can be notified to improve the safety. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the gas shut-off device of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention,
A flow measuring unit 1 that outputs a flow signal A corresponding to the amount of passing gas, a pressure detecting unit 2 that outputs a pressure drop signal B when a pressure sensor detects that the gas pressure in the gas passage has dropped to a certain value or more, The pressure determination unit 3 outputs the pressure determination signal D when the pressure drop signal B of the detection unit 2 is output, and outputs a cutoff warning signal C when the flow rate signal A of the flow measurement unit 1 is received. Shutdown warning signal C for part 3
Based on the above, a warning signal is notified to a monitoring center provided separately outside using a public communication line such as a telephone line, and a cut-off notification unit 4 for blocking a gas passage, and a flow signal A of the flow measurement unit 1 are monitored, and a flow rate signal A of a specific period is monitored. During a period of time (for example, one month), an unused time period of a gas in which a flow signal does not exist is detected in units of one minute, and the result is held. The flow rate learning unit 5 that outputs the pressure test request signal E at the ratio of: the flow rate signal A of the flow rate measurement unit 1 is absent, and the pressure test request signal E from the flow rateless learning unit 5 is present. If there is no signal D during the pressure determination, a gas passage opening / closing signal F for temporarily shutting off the gas passage of the interruption notification unit 4 and opening the gas passage after a certain period of time (immediately before the end of the time period when there is no flow rate) is output. It consists of a pressure test section 6.

FIG. 2 shows a program flow of the above means at T1.
To T19. Now, it is assumed that the flow from the processing start to the processing end is periodically processed by an interval calendar or the like. The process T1 (the number at the upper left of each block) in the pressure detector 2 determines the presence or absence of pressure. If there is pressure, the process proceeds to process T2. If there is no pressure, the pressure determination flag is cleared and the process proceeds to process T3. In the process T2 of the pressure determination unit 3, the flag during the pressure determination is set, and the process proceeds to the process T3. The process T3 in the flow rate measuring section 1 determines the presence or absence of a flow rate, and if there is a flow rate, the process proceeds to a process T4, and if not, the process proceeds to a process T9.

In the pressure judging section 3, it is judged whether or not the pressure is being judged in the process T4. If the pressure judging flag is set, the process shifts to a process T8. If the pressure judging flag is not set, the process shifts to a process T5. Processing T5 in learning section 5 without flow rate
Determines whether the learning period (for example, one month) has ended. If the learning period has ended, the process proceeds to process T7, and if not, the process proceeds to process T6. The process T6 records the time period in which the flow rate appears, and ends the process. Pressure test section 6
In the process T7, the pressure test timer is counted up and the process ends. The process T8 in the shutoff notifying unit 4 notifies the user of an alarm, shuts off the gas passage, and ends the process.

In the flowless learning section 5, the process T9 determines whether the learning period has ended. If the learning period has ended, the process proceeds to the process T10, and if not, the process ends. In the pressure test section 6, the process T10 counts up the pressure test timer, and proceeds to the process T11. Processing T11
Determines whether the pressure test timer has passed a predetermined time (for example, has passed one month and has reached a time zone where there is no flow rate). If it has passed, the process proceeds to process T12, and if not, the process has proceeded. To end.

In process T12, it is determined whether or not the flag is set during the pressure test period. If the flag is set during the test period, the process proceeds to process T15, and if not, the process proceeds to process T13. In process T13, it is determined whether the pressure determination flag is on. If the pressure determination flag is on, the process ends. If the pressure determination flag is not on, the flag is set during the inspection period, and the process proceeds to process T14. .
In the cutoff notifying section 4, the process T14 cuts off the gas passage and shifts to a process 15. Processing T15 in the pressure inspection unit 6
Starts counting up the inspection period timer and shifts to processing T16.

The pressure judging section 3 judges whether or not the pressure has decreased in a process T16. If the pressure has decreased, the process proceeds to a process T17. If the pressure has not decreased, the process proceeds to a process T18. In the cutoff notifying unit 4, the process T17 notifies that the pressure is abnormal, and ends the process. The process T18 in the pressure inspection unit 6 determines whether the inspection period timer has passed a predetermined period (immediately before the end of the time period during which there is no flow rate), and if the predetermined period has elapsed, clears the flag during the inspection period. Then, the process shifts to process T19, and if not, the process is terminated. In the cut-off notifying section 4, the process T19 opens the gas passage and ends the process.

As described above, the gas pressure drop test, that is, the gas leak test within a certain period, is conventionally performed by a gas distributor individually visiting a gas user's house to check for gas leak over several hours. In the present invention, the gas user is required to determine what had to be done, or what became evident only after monitoring the gas flow rate and continuously detecting that the gas was being used for as long as 30 days. Automatically detects time periods when the gas is not being used, and makes effective use of the time period when the gas is not used to completely automatically shut off, inspect, and open regularly (every week) without human intervention. By performing the test in a short period of time (several hours), it is possible to detect a gas leak at an early stage without restricting the gas use of the gas user as compared with the conventional case, so that the gas passage after the gas shutoff device can be detected. No gas leak Period can further improve safety by the shortening.

[0016]

As is clear from the above description, in the conventional case of gas leak inspection, a gas distributor visits a gas user's house individually and inspects the gas leakage, or the gas leakage inspection is carried out for a long period of 30 days. Detecting continuous use, and for the first time what became clear, the present invention automatically detects the time period when the gas user is not using the gas, and periodically shuts off, inspects, and opens without manual intervention. Automatic detection enables detection in a short time. In addition, this makes it possible to shorten the dead time of gas leakage in the gas passage after the gas shut-off device by detecting gas leakage at an early stage without restricting gas use by the gas user. Safety is improved.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a gas shutoff device according to an embodiment of the present invention.

FIG. 2 is a program flowchart of the apparatus.

FIG. 3 is a functional block diagram of a conventional gas shut-off device.

[Explanation of symbols]

 Reference Signs List 1 Flow rate measuring unit 2 Pressure detecting unit 3 Pressure judging unit 4 Shutdown notifying unit 5 Learning unit without flow rate 6 Pressure testing unit

Continuation of the front page (56) References JP-A-55-110824 (JP, A) JP-A-57-190200 (JP, A) JP-A-6-258170 (JP, A) JP-A-7-151574 (JP, A) , A) JP-A-63-101615 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23N 5/24 101 G01F 3/22 G05B 9/02

Claims (1)

(57) [Claims] 1. A flow rate measuring section for outputting a flow rate signal corresponding to a passing gas amount, a shutoff section for shutting off and opening a gas passage downstream from the apparatus, and a flow rate signal for monitoring the flow rate signal during a specific investigation period. Detects and holds the non-flow time zone where there is no
Thereafter, the flowless learning unit that outputs a pressure test request signal when the flow is in the no-time zone, and in the no-flow time zone, and when the flow signal is not received, instructs the shutoff unit to shut off the gas passage, and sets the pressure. A pressure inspection unit for instructing whether a pressure in a gas passage blocked by a pressure detection unit for detecting a change in pressure has decreased by a predetermined value or more within a predetermined time.