JPH0730916B2 - Gas shutoff device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shutoff device that automatically shuts off a gas passage when an abnormality occurs to prevent an accident such as an explosion or poisoning caused by city gas or propane gas. Regarding

2. Description of the Related Art A conventional gas shutoff device of this type is as shown in FIG.
Gas meter 2 in the gas supply line 1 and flow rate measuring means 3 for issuing a signal according to the amount of gas passing through the gas meter 2.
And a shutoff means 4 for stopping the supply of gas is provided. The shutoff means is determined to be abnormal when the usage state is judged by the flow rate signal of the flow rate measurement means 3 and the preset and stored total gas flow rate condition is deviated. 4 was provided with a control unit 5 for issuing a closing signal.

FIG. 5 shows a configuration example of the conventional control unit 5. Those having the same numbers as in FIG. 4 are components having the same function. The control unit 5 receives a flow rate signal from the flow rate measuring means 3 and detects a total flow rate of gas per unit time, and a use state detection section 6 and a predetermined total flow rate condition according to the number of the gas meter in advance. The initial condition setting unit 7 for setting the gas flow rate, the gas total flow rate condition setting unit 8 which stores the setting contents and sends a reference signal to the abnormality determination unit 9, and the shutoff unit 4 is closed in response to the signal from the abnormality determination unit 9. It is composed of a closing signal output unit 10 which emits a signal.

Here, the predetermined gas total flow rate condition is set according to the capacity of each gas meter, and indicates the total gas flow rate that passes through the gas meter within a predetermined measurement period (unit time). When the current total flow rate exceeds the preset predetermined value, for example, when the gas hose is pulled out or the gas appliance burns out while the gas is in use, the shutoff means 4 is operated to ensure safety.

However, in the above-mentioned configuration, the total gas flow rate condition is uniformly determined only by the initial condition set by the initial condition setting unit 7 according to the capacity of the gas meter 2 installed in the gas pipe. Therefore, there is a problem that special conditions such as a home where the gas meter 2 is installed are not incorporated.

The present invention solves the above conventional problems, and an object of the present invention is to provide a safer gas shutoff device by measuring the gas usage pattern of each home.

Means for Solving the Problems In order to solve the above problems, the gas shutoff device of the present invention is
It has a flow rate measuring means for issuing a signal according to the amount of gas passing through a gas meter provided in the gas supply line, and a shutoff means for stopping the supply of gas, and inputs the flow rate signal from the flow rate measuring means for a unit time. Usage state detection unit that detects the total flow rate of gas per hit, initial condition setting that sets a predetermined total flow rate condition in advance according to the number of the gas meter,
A gas total flow rate condition setting unit that stores the setting content, an abnormality determination unit that determines an abnormality when the signal from the usage state detection unit deviates from the gas total flow rate condition, and a signal from the abnormality determination unit A shutoff signal output unit that sends a gas shutoff signal to the shutoff unit, a timer that counts a predetermined period, a start signal application unit that starts the timer, and a maximum value of the total gas flow rate per unit time during the timer operation. Which of the gas flow rate classifications obtained by dividing the usage state storage means to be memorized and the gas combustion appliance used from the change of the gas flow rate per unit time during the timer operation over a predetermined value Classification determination storage means for determining the corresponding classification and storing the corresponding classification, the maximum value of the total gas flow rate stored in the usage status storage means, and the usage thereof are stored in the classification determination storage means. Compare the added value of the maximum gas flow rate for each gas flow rate category, select a larger value, compare that value with the initial condition of the initial condition setting section, and use the smaller value as the new total flow condition. The control unit comprises a total gas flow rate condition changing means for changing the conditions of the flow rate condition setting unit.

Operation According to the present invention, when the activation signal is applied to the timer, the present invention starts counting for a predetermined time, and during the counting period, the maximum value of the total gas flow rate per unit time is updated by the operation of the usage state storage means. If the gas flow rate per unit time changes by a predetermined value or more by the classification determination storage means, which of the gas flow rate classifications obtained by dividing the gas combustion appliance used in advance into multiple parts? Is determined and stored. That is, during this period, the actual measurement value of the total flow rate described above is updated, and it is determined what kind of gas flow rate equipment is used in the gas supply system in which the gas meter is installed. Simultaneously with the end of the timer, each final data is compared and judged by the gas total flow rate condition changing means including the initial condition set by the initial condition setting section, and a predetermined value is selected and sent to the gas total flow rate condition setting section. The condition is newly set. After that, the abnormality determination unit compares the new setting condition with the signal from the usage state detection unit, and if the condition is not satisfied, it is determined to be abnormal and the cutoff unit is activated.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, those having the same numbers as those in FIG. 5 are components having the same function. The control unit 11 inputs a flow rate signal from the flow rate measuring means 3 similar to the conventional one, and detects a total flow rate of gas per unit time, and a use state detection section 6 and a predetermined total flow rate according to the number of the gas meter in advance. An initial condition setting unit 7 for setting conditions, a total gas flow rate condition setting unit 12 for storing the setting contents and sending a reference signal to the abnormality determination unit 9,
A closing signal output unit 10 for issuing a closing signal to the shutoff unit 4 in response to a signal from the abnormality judging unit 9, a timer 13 for counting a predetermined time, and a starting signal applying unit 14 for sending a starting signal for starting counting to the timer. With the start of operation of the timer, the gas flow rate per unit time is set to a predetermined value by the signal from the usage state storage means 15 that stores the maximum value of the total flow rate in accordance with the signal from the usage state detection section and the flow rate measurement means 3. When the above change occurs, the gas combustion appliance used is divided into a plurality of gas flow rate divisions obtained in advance and is classified and stored in the classification determination storage means 16, and at the end of the timer, the usage state storage means 15 The maximum value of the total gas flow rate stored in the above is compared with the added value of the maximum gas flow rate for each gas flow rate category whose use is stored in the category determination storage means 16, and a larger value is selected. And a gas total flow rate condition changing means 17 for changing the condition of the gas total flow rate condition setting unit 12 by comparing the value with the initial condition of the initial condition setting unit 7 and setting a smaller value as a new total flow rate condition. ing.

In the above configuration, when the activation signal application means 14 (eg, push button switch, external signal transmission means, etc.) is activated, an activation signal is sent to the timer 13, and the timer 13 receives the signal and starts counting for a predetermined time. . The predetermined time may be set in advance or may be set arbitrarily, but is a span such as one week and one month. At the same time as the operation of this timer 13,
The usage state storage means 15 stores the maximum value of the total gas flow rate.

In the classification determination storage means 16, for example, as shown in the table below, classification 1
The gas flow rate section is divided into a plurality of sections from to section n.
(Qu; kcal / h) That is, the gas flow rate pulse is converted into the amount of heat generation to specify each flow rate section. Because the calorific value per the same flow rate pulse differs depending on the type of gas, it is easier to consider the calorific value when considering the explosion limit of a gas accident as an evaluation item. And
When the flow rate pulse per unit time from the flow rate measuring unit 3 changes by a predetermined value or more (for example, 3% or more), it is determined that one of the installed gas appliances has started burning or has stopped burning. Then, the combustion amount when the flow rate pulse is increased is classified into categories by referring to the above table, and the relevant categories are stored in the category determination storage means 16. Actually, it is difficult to make a reliable judgment without registering the appliances in advance because there are a plurality of gas appliances of the same section and there are appliances that can change the fuel amount, but the total flow rate judgment of the present invention is difficult. Can be usefully acted on. In this way, the classification determination storage means 16 stores and holds the size of the gas appliance used during the operation of the timer 13 in the combustion amount classification. Then, at the end of counting, the maximum combustion amount of each section (QuMAX in section n) stored above is added, and the data is sent to the total gas flow rate condition changing means 17.

The maximum value of the total gas flow rate stored in the usage state storage means 15, the added value of the maximum gas flow rate for each gas flow rate category whose usage is stored in the classification determination storage means 16, and the initial condition setting unit 7 The initial condition of is the total gas flow rate condition changing unit 17
Compared with. First, the former two, that is, the maximum value of the total gas flow rate stored in the use state storage means 15 and the added value of the maximum gas flow rate for each gas flow rate category whose use is stored in the classification determination storage means 16 A force having a larger value is selected from among the above, and this value is then compared with the initial condition of the initial condition setting unit 7, and the smaller value is selected as the final comparison result. This result is newly set in the setting unit 12 as a new gas total flow rate condition, and thereafter, it is determined whether or not the total flow rate is abnormal based on this value. Here, the maximum value of the total flow rate actually measured and the added value of the maximum gas flow rate for each gas flow rate category for which usage was stored were used for comparison and examination as is, but they were used as comparison data by multiplying by a predetermined coefficient. May be.

Here, the comparison of both the maximum total flow rate and the added value of the maximum gas flow rate for each gas flow rate category for which use was memorized could not be recognized by the category determination when there was an instrument in the same combustion amount range. Sometimes, it is intended to cover the total flow rate, and to supplement it with the added value of the maximum gas flow rate for each gas flow rate category whose use was remembered when there was an appliance that was not used simultaneously during the timer period. .

By the way, until the above timer count ends,
The abnormality judging section 9 judges the abnormal state by comparing the current gas use state with the initial condition set by the preset initial condition setting section 7, but the gas use pattern measurement result during the operation of the timer 13 After the condition is newly set from (1), the reset value is compared with the signal from the gas usage state detection unit 6 to determine the abnormal state. here,
When it is determined that there is an abnormality, the shutoff means 4 is activated and the gas passage is closed.

The control unit 11 described above can be easily realized by using a calculation or judgment function by a program operation of a microcomputer or the like. Hereinafter, FIG. 2 shows a schematic program flow.

When the program starts, after initializing the total gas flow rate condition by the initial condition setting unit 7 at A, the flow rate is measured at B, and then at C, it is judged whether the timer is counting or not, In this case, after the gas flow rate classification is determined and the equipment used is stored in D as described above, the gas usage state, that is, the total gas flow rate per unit time, is detected in E as in the case where counting is not being performed. Then, at F, it is determined whether or not the timer 13 for a predetermined time is counting,
When counting, the usage state is stored in G and the maximum total flow rate is updated. Then, as in the case where the timer 13 is not operating, the total gas flow rate condition is compared with the usage state detection value at H. If the result of this comparison is that there is an abnormality, it branches at I and jumps to the J closing signal output section. When it is not abnormal, it is checked in K whether the total gas flow rate condition unit 17 has operated, and when it has been operated, the flow returns to h1, that is, A flow rate measurement. When the operation has not been completed, L is used to determine whether or not the timer count has ended. When the operation has been completed, M is used to operate the gas flow rate condition changing unit 17. Although the details of M will be described later, the value selected by M is reset by N. After that, in H, the reset value is treated as a gas total flow rate condition, and compared with the detected value. When the timer count is not completed at L, the process branches at O to determine whether or not the timer is currently being counted. P when counting
Continue counting as it is, and if it is not counting, the presence or absence of the start signal is determined in Q. When the activation signal is input, the timer count is started by R. If there is no signal, it returns to A again.

The details of M (gas total flow rate condition changing means operation) in FIG. 2 will be described in detail with reference to FIG. B. Usage status storage means 15
The maximum total flow rate S1 of S and the maximum gas flow sum S2 for each gas flow rate category whose use is stored in the category determination storage means 16 are compared, and the larger one of S1 and S2 is selected with C. Then S3. Then, the initial conditions S4 and S3 set by the initial condition setting unit 7 are compared with each other, and the smaller one is selected by E.
After that, the process proceeds to the above-mentioned N, and the contents of E are reset as the total gas flow rate condition.

By executing the above program flow, the function of the control unit 11 of the gas shutoff device of the present invention can be realized.

Effects of the Invention As described above, the gas cutoff device of the present invention has the following effects.

(1) By constantly monitoring the gas usage state and comparing it with the set total flow rate, it is possible to detect gas leakage or combustion extinction due to gas supply hose disconnection, etc., and when the conditions are exceeded, that is, When it is determined that there is an abnormality, the shut-off means is activated to stop the gas supply, so that it is possible to prevent a dangerous state such as gas explosion or gas poisoning.

(2) The actual use pattern of the gas supply system in which the gas meter is installed is observed for a predetermined time by the start signal, and the maximum value of the total gas flow rate stored in the use state storage means 15 and the use in the classification determination storage means 16 are observed. Of the stored maximum gas flow rate for each stored gas flow rate category is compared and a larger value is selected,
Since that value is compared with the initial condition of the initial condition setting unit 7 and the smaller value is set as a new total flow condition, and the condition of the gas total flow condition setting unit 12 is reset, it is simply determined by the capacity (number) of the gas meter. Judgment is made in consideration of individual special conditions in comparison with the conditions that were uniformly decided, and it is possible to further increase the safety level against gas accidents without affecting actual use.

[Brief description of drawings]

FIG. 1 is a block diagram of a gas shutoff device in an embodiment of the present invention, FIG. 2 is a diagram showing a schematic program flow of a control unit of the device, and FIG. 3 is a content of a total gas flow rate condition changing means in the device. FIG. 4 is a diagram showing the program flow of FIG. 4, FIG. 4 is a block diagram of a conventional gas shutoff device, and FIG. 5 is a block diagram of a conventional control unit. 2 ... Gas meter, 3 ... Flow rate measuring means, 4 ... Shutoff means, 11 ... Control section, 13 ... Timer, 14 ... Activation signal applying means, 15 ... Use state storing means, 16 ... Classification judgment Storage means, 17 ... Means for changing the total gas flow rate condition.

Claims (1)

[Claims] 1. A flow rate signal from said flow rate measuring means, comprising flow rate measuring means for emitting a signal according to the amount of gas passing through a gas meter provided in the gas supply line, and shutting off means for stopping the gas supply. Input state to detect the total flow rate of gas per unit time, an initial condition setting section that sets a predetermined total flow rate condition according to the number of the gas meter in advance, and a total gas that stores the setting contents. A flow rate condition setting unit, and an abnormality determination unit that determines that the signal from the usage state detection unit is abnormal when the signal exceeds the gas total flow rate condition,
A closing signal output unit that sends a gas closing signal to the shutoff unit in response to a signal from the abnormality determination unit, a timer that counts a predetermined period, a start signal applying unit that starts the timer, and a unit during the timer operation. The usage state storage means for storing the maximum value of the total gas flow rate for each hour, and the gas combustion equipment used from the change of the gas flow rate per unit time or more during the timer operation are divided into a plurality of parts in advance. Classification determination storage means for determining which of the obtained gas flow rate classifications it belongs to and storing the corresponding classification, the maximum value of the total gas flow rate stored in the usage state storage means, and the usage in the classification determination storage means. Compare the stored maximum gas flow rate addition values for each stored gas flow rate category, select a larger value, compare that value with the initial conditions of the initial condition setting section, and select a smaller value as a new value. Gas cutoff apparatus provided with a control unit comprising a gas total flow rate condition changing means for changing the condition of the gas total flow rate condition setting unit as the flow rate conditions.