JPH0743126B2 - 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 3.
A shut-off means 4 for stopping the supply of gas is provided, and it is judged to be abnormal when the usage condition is judged by the flow rate signal of the flow rate measuring means 3 and the preset continuous stored allowable time condition of gas is deviated. The blocking means 4 was provided with a control section 5 for issuing a blocking signal.

FIG. 5 shows a configuration example of this conventional control unit. Those having the same numbers as in FIG. 4 are components having the same function. The control unit 5 calculates the heat generation amount of the gas amount passing through the gas meter per unit time based on the signal from the flow rate measuring means, and the gas heat generation amount division obtained by dividing the heat generation amount into a plurality of units in advance. A classification determination unit 7 for determining which one belongs to, an initial continuous use allowable time setting unit 8 for setting an allowable time that can be continuously used in advance corresponding to the classification determined by the classification determination unit, and calculation by the calculation unit The continuous use time judging unit 9 compares the continuous use time after the gas having the above-mentioned calorific value starts to flow with the allowable continuous use time and outputs a cutoff signal when the former exceeds the latter. Upon receiving the cutoff signal, the cutoff means 4 closes the gas passage.

Here, the continuous use time is the continuously usable time set for each range from the statistical data of the time when the gas appliance in the predetermined calorific value range is continuously used, and the data from the classification determination unit is the above-mentioned. When the set time is exceeded, an operation signal is sent to the shutoff means, and it is a judgment condition for ensuring safety even when forgetting to turn off the gas appliance.

In the classification determination unit 7, for example, as shown in Table 1, the gas flow rate classification from the classification 1 to the classification n is divided into a plurality (Qu; kca).
l / 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 means 3 changes by a predetermined value or more (for example, 3% or more), it is determined that any of the installed gas appliances has started or stopped burning. Then, it is registered in a predetermined category in light of the above table.

By the way, the initial continuous use permissible time setting unit 8 determines the permissible time for each combustion amount category, for example, as shown in Table 2.

FIG. 6 is a graph of the contents of the above table, in which the horizontal axis represents the amount of heat generation and the vertical axis represents the allowable continuous use time. L1
Indicates a series of characteristic values.

Problems to be Solved by the Invention However, in the above-mentioned configuration, the allowable continuous use time condition is uniformly determined only by the initial value depending on the capacity of the gas meter installed in the gas pipe. There was a problem that special conditions such as the above were not incorporated.

The present invention solves such a conventional problem, and an object of the present invention is to provide a safer gas shutoff device by measuring the 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
A flow rate measuring unit that emits a signal according to the amount of gas passing through the gas meter provided in the gas supply line, and a calculation unit that calculates the heat generation amount per unit time of the gas meter passing gas amount by a signal from the flow rate measuring unit, A classification determination unit that determines which one of the gas heating value classifications obtained by dividing the calorific value in advance, a permissible time that can be continuously used in advance corresponding to the classification determined by the classification determination unit. Set initial continuous use allowable time setting section, compare the continuous usage time after the gas of the calorific value calculated in the calculation section starts to the allowable continuous usage time, and output a cutoff signal when the former exceeds the latter The continuous use time determination unit, the timer for counting a predetermined period, the activation signal applying means for activating the timer, and the maximum value of each continuous use time of each heat generation amount category while the timer is operating. Use state storage unit, maximum value in each heat generation amount category stored in the use state storage unit at the end of counting of the timer or a value obtained by multiplying the maximum value by a predetermined coefficient and initial continuous use for each heat generation amount category Compared with the permissible time, selecting a smaller one and newly changing it as the permissible time in the continuous use time determination section, the control unit comprising the permissible continuous use time changing unit, and the gas depending on the cutoff signal from the control unit. It is provided with a structure of a blocking means for blocking the passage.

Operation According to the present invention, when the start signal is applied to the timer, the present invention starts counting for a predetermined period, and during the counting period, the continuous use time of each heating value category is stored by the operation of the use state storage unit. The maximum value is updated. Simultaneously with the end of the timer, the final data is compared and judged with the initial value by the continuous use permissible time changing unit, a predetermined value is selected and sent to the continuous use time judging unit, and new conditions are reset. After that, in this judging section, the above-mentioned new setting condition is compared with the signal from the classification judging section, and when the condition is deviated, it is judged as abnormal and the breaking means 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 10 inputs the flow rate signal from the flow rate measuring means 3 similar to the conventional one and calculates the calorific value per unit time, and the gas calorific value classification obtained by previously dividing the calorific value into a plurality of parts. A classification determination amount 7 for determining which of the above, an initial continuous usage allowable time setting unit 8 that sets an allowable time that can be continuously used in advance corresponding to the classification determined by the classification determination, and the calculation unit. The continuous use time determination unit 9 that compares the continuous use time after the gas having the calorific value calculated in step 1 has started to flow with the allowable continuous use time and outputs a cutoff signal when the former exceeds the latter, and counts a predetermined time Timer 11, a start signal applying means 12 for sending a start signal to the timer to start counting, and the maximum value of each continuous use time of each heat generation section according to the signal of the section determination unit 7 when the operation of the timer is started. Remember Usage state storage unit 13, the maximum value in each heat generation amount stored in the use state storage unit 13 at the end of counting of the timer 11 or a value obtained by multiplying the maximum value by a predetermined coefficient and each heat generation amount category. It comprises an allowable continuous use time changing unit 14 which compares the initial allowable continuous use time and selects a smaller one to newly change the allowable time in the continuous use time judging unit 9.

In the above configuration, when the activation signal applying means (for example, the push button switch, the signal transmission means from the outside, etc.) is activated, the activation signal is sent to the timer, and the timer receives the signal and starts counting for a predetermined period. The predetermined time may be set in advance or may be set arbitrarily, for example, a span of one week or one month. Simultaneously with this timer operation, the maximum value of each continuous use time of each heat generation amount section is stored in the use state storage section. Then, at the end of the count, the maximum value of the usage time in each section stored above is sent as data to the continuous usage allowable time changing unit. The changing unit compares the data with the initial allowable time condition for each heat generation amount category and selects the smaller one. This result is newly set as the continuous use permissible time condition in the continuous use time determination unit, and thereafter, it is determined whether or not the signal from the classification determination unit is abnormal based on this value. Here, the maximum value of the usage time in each calorific value category that has been actually measured is used as it is for comparison and examination, but it may be used as comparison data by multiplying it by a predetermined coefficient. That is, the reset value may be selected in consideration of the safety factor in terms of usability.

By the way, until the above timer count ends,
The continuous use time determination unit compares the current gas use state with the preset initial condition to determine an abnormal state, but the condition was newly set based on the gas use pattern measurement result during timer operation. After that, the abnormal state is judged by comparing with the reset value. Here, when it is determined that there is an abnormality, the shutoff means is activated and the gas passage is closed.

Fig. 2 shows an example L2 of the measurement results of the usage time. Each axis and L1 are the same as in FIG. In the figure, L2 takes less time than L1, and L2 is selected as the reset value in the operation of the changing unit described above.

The control unit 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. 3 shows a schematic program flow.

When the program starts, after setting the initial allowable time in A, calculate the calorific value from the flow rate pulse in B,
Then, in C, the classification of the corresponding heat value is registered and the usage time is measured. Then, in D, it is determined whether or not the timer for a predetermined time is counting, and when the timer is counting, in E, the gas use state, that is, which calorific value segment is continued and how long is used is stored. The maximum value is updated. Then, as in the case where the timer is not operating, the continuous use allowable time set in F is compared with the signal from the classification determining unit. As a result of this comparison, when abnormal, that is, when the permissible time is exceeded, branch is made at G, jumps to the cutoff signal output at H, and the timer count is reset at Q. That is, if the gas usage state exceeds the initial set time, it is meaningless to continue storing data because of an abnormality, so the timer is stopped. When it is not abnormal, it is checked whether or not the changing means is operated by I, and when it is operated, the process returns to h1, that is, the heat generation amount calculation of A. If it has not been activated, J is used to judge whether or not the timer count has ended.
The use state is compared with the initial setting condition by K, a predetermined value is selected, and the allowable time is reset by L. After that, in F, the reset value is treated as a gas continuous use allowable time condition, and is compared and compared with the detected value. When the timer count is not finished at J, the process branches to M to determine whether or not the timer is currently counting. If it is counting, N continues counting as it is, and if it is not counting, O is used to determine the presence or absence of a start signal. When the activation signal is input, the timer count is started at P. If there is still no signal, it returns to A again.

By executing the above program flow, the function of the control unit 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) It is possible to detect abnormal continuous use of the gas appliance due to forgetting to turn it off by constantly monitoring the gas use state and comparing it with the set allowable continuous use time condition. That is, when it is determined that there is an abnormality, the shutoff 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) Observe the actual usage pattern of the gas supply system where the gas meter is installed for a predetermined time by the start signal, and reset the maximum value of the actual continuous usage time of the gas appliance and the smaller of the initial conditions as the final result. Therefore, compared to the condition that was uniformly determined by the capacity (number of gas meters) of the gas meter, individual special conditions are also taken into consideration for the judgment, and the degree of safety against gas accidents does not interfere with actual use. Can be further increased.

[Brief description of drawings]

FIG. 1 is a block diagram of a gas shutoff device according to an embodiment of the present invention, FIG. 2 is a heat generation amount classification diagram showing actual measurement results of continuous use time by the device, and FIG. 3 is a schematic program of a control unit of the device. FIG. 4 is a diagram showing a flow, FIG. 4 is a configuration diagram of a conventional gas shutoff device, FIG. 5 is a block diagram of a conventional control unit, and FIG. 6 is a heat generation amount division diagram showing an initial condition of an allowable continuous use time. 2 ... Gas meter, 3 ... Flow rate measuring means, 4 ... Shutoff means, 6 ... Calculation part, 7 ... Classification determination part, 8 ... Initial continuous use allowable time setting part, 9 ... Continuous use time determination part ,Ten…
… Control unit, 11 …… Timer, 12 …… Starting signal applying means,
13: Usage status storage section, 14: Continuous usage allowable time change section.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-53-49339 (JP, A) JP-A-56-97747 (JP, A) Actual opening Sho-53-166133 (JP, U) Actual opening Sho-59- 181957 (JP, U)

Claims (1)

[Claims] 1. A flow rate measuring means for emitting a signal in accordance with the amount of gas passing through a gas meter provided in a gas supply line, and a signal from the flow rate measuring means for determining the amount of heat generated by the gas meter passing gas per unit time. A computing unit that computes, a classification determination unit that determines which of the gas calorific value classifications the heating value belongs to is obtained by dividing the heating value in advance, and continues to use in advance corresponding to the classification determined by the classification determination unit. Initial continuous allowable use time setting unit for setting possible allowable time, comparing the continuous use time after the gas of the calorific value calculated by the calculation unit starts to the continuous use allowable time, and the former exceeds the latter A continuous use time determination unit that outputs a cutoff signal, a timer that counts a predetermined period, a start signal applying unit that starts the timer, and a continuous use time of each heat generation amount category during operation of the timer. A usage state storage unit that stores a large value, a maximum value in each heating value category stored in the usage state storage unit at the end of counting of the timer, or a value obtained by multiplying the maximum value by a predetermined coefficient and each heating value category In comparison with the initial continuous use permissible time, a smaller one is selected to newly change the permissible time in the continuous use time determination unit to a control unit including a continuous use permissible time changing unit, and a cutoff signal from the control unit. And a gas shutoff device for shutting off the gas passage according to the above.