JPS61137038A - Gas blocking control apparatus - Google Patents

Abstract

PURPOSE:To reduce the number of blocking times while attaining safety, by changing the time reaching the blocking of gas from a time, when an accident of gas from a time, when an accident was generated, corresponding to a time zone and the flow amount of supplied gas when the blocking of gas is performed on the basis of a gas leakage detection signal. CONSTITUTION:When gas leakage is generated in a gas instrument 3, a gas leakage detector 1 is operated to send out gas leakage information to an operation circuit 23. Because gas flow amount information is always sent to the operation circuit 23 from a flowmeter 5, the time for blocking gas is operated from the gas flow amount information and time information to perform the setting of the time of a timer 24. The timer 24 applies gas blocking information to blocking valve 4 after the set time was elapsed. At this time, because the operation circuit 23 monitors the time information from a clock circuit 25, said circuit 23 performes different operation corresponding to a time zone.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas cutoff control device that shuts off gas by driving a cutoff valve based on gas leakage information from a gas leakage detector.

[Conventional technology]

If a gas leak occurs with fuel gases such as city gas or procyon gas, it can cause gas poisoning or explosions, so there are ways to detect this with a gas leak alarm and notify with a buzzer, or simply to issue an alarm. In addition to emitting gas, there is a method of actively shutting off the supply gas in conjunction with a gas cutoff valve. In such cases, semiconductor-type or catalytic-type detectors are widely used to detect gas leaks.

[Problem that the invention seeks to solve]

However, since these senna detect hydrocarbons (CO), they also detect hydrocarbons other than city gas and propane gas, such as alcohol contained in alcoholic beverages, and therefore gas leak detectors may not emit a signal. Even if it does, it may be difficult to conclude that it is a gas leak.

In addition, in systems that operate the gas cutoff valve in response to a gas leak detection signal, the gas detector and the cutoff valve are generally linked, so that the gas is shut off immediately when the gas leakage signal is issued. It has become. However, even if a gas leak occurs and the sensor is activated, for example, if a gas appliance's pilot burner goes out, it is sufficient to simply open a window or take ventilation measures, and it is not necessary to cut off the supply gas. There's no need to do it. In other words,
If the gas is shut off even in such a severe case, it will be cumbersome since it will be necessary to perform operations such as re-igniting all the gas appliances that have been in use at an appropriate time thereafter. On the other hand, if the main burner of a large gas appliance such as a bathtub goes out and a gas leak detector is activated and a signal is issued, the gas must be shut off immediately. Furthermore, even if the cause of a gas leak is the same, the way to deal with it during the day and late at night may be different. In other words, even when a gas leak occurs, there are cases in which the gas must be shut off immediately and cases in which it is not necessary.

[Means and effects for solving the problem] This invention shuts off the gas based on the gas leak detection signal and transmits information to five buildings based on the time or time of day (morning, noon, midnight, etc.). By changing the time from the occurrence of an accident to the gas shutoff depending on the supply gas flow rate, safety is ensured and the number of shutoffs is reduced.

[Embodiments of the invention]

FIG. 1 is a block diagram showing an embodiment of the present invention, the first person's figure is a block diagram showing a specific example of an arithmetic device, and FIG. 2 is an explanatory diagram for explaining the operation of the arithmetic device. In Figure 1,
1 is a gas leak detector, 2 is a computing device, 3 is a gas appliance, 4
5 is a shutoff valve, and 5 is a flow meter (gas meter). In addition, as the gas leak detector 1, the cutoff valve 4, and the flow meter 5, conventionally used gas leak detectors with contact output, electric pulse input cutoff valves, and gas meters with contacts can be used as they are. can. Therefore, the flow rate information is sent to the computing device 2 as contact information that is output at every predetermined flow rate, and the gas leak information is sent to the computing device 2 as contact signal information that is turned on when a gas leak occurs and the gas leak detector 1 is activated. is input. The calculation device 2 includes, for example, as shown in FIG. 1A, a pulse counter 21 that calculates the flow rate from time to time based on the above flow rate information, a memory 22 that stores the calculated flow rate, and a clock circuit 25 that outputs time information. ,
A calculation circuit 26 calculates gas cutoff conditions from gas flow rate information and time information when the gas leak information starts, and time information for gas cutoff given from the calculation circuit 25 is measured using a time signal from the clock circuit 25. It is composed of a timer 24 and the like that outputs gas cutoff information. In addition, the contact is on.

The method of calculating the flow rate from the flow rate information due to OFF is as follows.
There are methods to count how many times a contact turns on and off within a unit time, and a method to count each interval between on and off or off and off using a reference pulse, but in any case, counter 21 and the time reference pulse output from the clock circuit 25, the flow can be measured. Therefore, when a gas leak occurs in the gas appliance 3, the gas leak detector 1 operates and gas leak information is sent to the arithmetic circuit 23. At this time, the arithmetic circuit 23 has
Since the gas flow rate information is constantly being sent out from the flow meter (gas meter) 5, the calculation circuit 23 calculates the time for gas cutoff from the gas flow rate information and time information, and sets the timer 240 hours.

The timer 24 provides gas cutoff information to the cutoff valve 4 after the set time has elapsed, so that the gas supply is cut off. At this time, the arithmetic circuit 23 monitors the time information from the clock circuit 25, so even if the gas flow rate information when a gas leak is detected is the same, different calculations may be made during the daytime and late at night, for example. It becomes possible to do this. This is to deal with the fact that the types of gas appliances used during the day and at night may be different, or that the same gas appliance may be used in different ways. Therefore, the time information in this case is not detailed in seconds or minutes (hour or time zone information is sufficient).

Next, a specific example will be explained with reference to FIG.

In the figure, td indicates the gas leak occurrence (detection) time, and t indicates the gas cutoff time.

FIG. 2A shows a case where a gas leak occurs almost simultaneously with a sudden increase in the gas flow rate, which is a phenomenon that occurs when, for example, a large gas appliance malfunctions in ignition. In this case, in order to immediately shut off the gas, the gas is shut off at time t, which is t1 hours after time td.

Contrary to (A), (B) in the same figure shows a phenomenon that occurs when a pilot burner or the like of a large gas appliance goes out at approximately the same time as the fire is extinguished. In this case, first an alarm is issued and a certain period of time (
The gas is shut off only when the alarm does not stop even after t2) (when the gas leak information does not disappear). Therefore, if the alarm stops within a certain period of time,
There will be no gas cutoff. Also, the same figure (C)
This is a phenomenon that occurs, for example, when the fire of a large gas appliance goes out midway through.In this case, it is extremely dangerous, so the gas must be shut off immediately (after 15 hours to be exact).

Furthermore, as shown in (D) in the same figure, this occurs when, for example, a pilot burner or other equipment that uses a small amount of gas goes out. In this case, as in the case in (B), an alarm is first issued and the If the alarm does not stop even after the time (t4) has elapsed, the gas is shut off.

Incidentally, each of the above-mentioned times t1 to t4 is calculated by the arithmetic unit 2, and if it is assumed that the times t1r, t2+t3 and t4 are, for example, during the daytime, then t1', t2', and ts/at night. and t4/, respectively.

〔Effect of the invention〕

According to this invention, when a gas leak is detected, the time until the gas is shut off is changed according to the gas flow rate information and time information, so that disasters caused by gas leaks can be reliably prevented. Since the number of times the gas is shut off is reduced as much as possible, there is an advantage of being freed from the complexity of post-processing after the gas shutoff.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 1A is a bronze diagram showing a specific example of the arithmetic unit in FIG. 1, and FIG. 2 explains the operation of FIG. 1 or FIG. 1A. FIG. Description of symbols 1... Gas leak detector, 2... Arithmetic device, 3... Gas appliance, 4... Gas cutoff valve, 5... ...Flowmeter, 21...Counter, 22...Memory, 23...Arithmetic circuit, 24...Timer, 25...Clock circuit. Agent Patent Attorney Akio Namiki Agent Patent Attorney Kiyomachi Matsuzaki 1 Figure 1A Figure (A) (C) dflj +Na Figure (D)

Claims (1)

[Claims] A gas flow meter that measures the gas flow rate supplied to gas appliances, a gas leak detector that detects gas leaks from gas appliances, and a shutoff valve that shuts off the gas supplied to gas appliances when a gas leak is detected. and a calculation device that calculates the time until the shutoff valve is closed based on at least time zone information and gas flow rate information obtained via the gas flow meter at the time when a gas leak is detected, A gas cutoff control device characterized in that a gas cutoff is performed based on the calculation output.