JPH0743129B2 - 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 operating signal is sent to the shutoff means, and this 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.

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, 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 Table 2, in which the horizontal axis represents the amount of heat generation and the vertical axis represents the allowable continuous use time.
L1 refers to 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 measure a usage pattern of each home, shorten an allowable time according to actual use, and provide a gas shutoff device having a higher safety factor. .

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 of the gas calorific value classifications obtained by dividing the calorific value into a plurality of values in advance, an allowable time that can be continuously used in advance corresponding to the classification classified 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. The usage state storage unit, the value obtained by multiplying the first predetermined coefficient equal to or greater than the actually measured maximum value 1 for the heat generation amount category whose use is observed in the usage state storage unit at the end of counting by the timer, and the initial value. The smaller one of the two values is used as the allowable time in the continuous usage time determination unit by newly multiplying the initial value by the second predetermined coefficient of 1 or less for the heating value category in which the usage is not observed. The control unit is composed of a continuous use permissible time changing unit that is set, and a shutoff unit that shuts off the gas passage in response to a shutoff signal from the control unit.

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. Then, at the same time as the timer ends, the final data is compared and judged with the initial value by the allowable continuous use time changing section, and the predetermined value is selected and sent to the continuous use time judging section as described above, and the new condition is reset. Is done. 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 to be 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 determining unit 7 for determining which of the above, an initial continuous use 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 determining unit; The continuous use time determination unit 9 that outputs a cutoff signal when the former exceeds the latter and compares the continuous use time after the gas of the calorific value calculated by the unit starts to flow with the allowable continuous use time, and the predetermined time A timer 11 for counting, a start signal applying means 12 for sending a start signal for starting counting to the timer, and a maximum of each continuous use time of each heat generation amount classification according to the signal of the classification determination unit 7 when the operation of the timer is started. Remember value That the use state storage unit 13, and a continuous use allowable time changing unit 14 for changing the allowable time in the continuous use time determining unit according to the information of the storage unit.

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 period may be set in advance or may be set arbitrarily, and is, 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. In the change unit, for the calorific value category in which the use of the gas appliance is observed, the value obtained by multiplying the actually measured maximum value by the first predetermined coefficient of 1 or more is compared with the initial value, and the smaller one is In addition, for the calorific value category for which usage has not been observed, an initial value multiplied by a second predetermined coefficient of 1 or more is selected. 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 first predetermined coefficient may be 120%, for example, and a safety coefficient for actual use of 20% may be taken into consideration. The second predetermined coefficient may be 50%, and the initial value may be changed to 1/2. Further, it is also effective to use the average value or the minimum value as the second predetermined coefficient based on the ratio of the actually measured value to the initial value.

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 (two lines) of the measurement result of the usage time.
Each axis and L1 are the same as in FIG. In the figure, L2 takes less time than L1, and in the operation of the changing unit described above, as the reset value for the areas of categories 1, 2, 4, ...
L2 is selected. In addition, since the use of gas was not actually measured in Category 3 ... n-1, the second predetermined coefficient (50%)
Is set to the reset value (broken line).

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 period is counting. When the timer is counting, in E, the gas usage state, that is, which calorific value segment is continuously stored and for how long 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, the flow branches to G and jumps to the H cutoff signal output. 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 the timer count is over, and when it is finished, K is used to compare the usage state with the initial setting condition. Select the smaller of the value multiplied by the predetermined coefficient of 1 and the initial value, or the value obtained by multiplying the initial value by the second predetermined coefficient for the calorific value category in which use was not observed, The allowable time is reset with 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. N when counting
Continue counting as it is, and if not counting, the presence or absence of the start signal is judged at O. When the activation signal is not input, the timer count is started at P. If there is 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) The actual use pattern of each calorific value category of the gas supply system in which the gas meter is installed is observed for a predetermined period by the start signal, and the measured maximum value of 1 or more for the calorific value category in which use is observed. Select the smaller of the value obtained by multiplying the predetermined coefficient by the initial value, or the value obtained by multiplying the initial value by the second predetermined coefficient of 1 or less for the calorific value category for which use was not observed. Since it is reset, it is interpolated in the non-observation area, and compared with only the condition that was uniformly determined by the capacity (number) of the gas meter, it is judged considering individual special conditions, The safety against gas accidents can be further increased without affecting the actual use.

[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 that also shows 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, and a heat generation amount category whose use is observed in the information of the usage state storage unit at the end of counting by the timer, multiply the actually measured maximum value by a first predetermined coefficient of 1 or more. The smaller of the measured value and the initial value, or for the calorific value category in which no use was observed, the value obtained by multiplying the initial value by a second predetermined coefficient of 1 or less is used by the continuous use time determination unit. The gas shutoff device is provided with a control unit including a continuous use permissible time changing unit that resets the permissible time, and a shutoff unit that shuts off the gas passage according to a shutoff signal from the control unit.