| 摘要 |
PURPOSE:To prevent a dangerous condition, such as gas explosion, the poisoning of the gas or the like, by a method wherein the using condition of the gas is monitored at all times to compare it with a set allowable time condition of the continuous using of the gas and when the using condition is decided to be abnormal, an interrupting means is operated to stop the supply of the gas. CONSTITUTION:When a starting signal impressing means 12 or a push-button switch, for example, is operated, a starting signal is sent to a timer 11 and the timer starts the counting of a predetermined period of time. Simultaneously with the operation of the timer, a using condition storing unit 13 stores the maximum values of respective intermittent using times of respective divisions of calorific values. Upon finishing the counting, the maximum stored values of the using times in respective divisions are outputted to a continuous using allowable time changing unit 14 as data. The changing unit compares the data with the initial period allowable time conditions in every divisions of calorific values and selects a smaller value. The result of the selection is set again in a continuous using time deciding unit 9 newly as a continuous using allowable time condition and, thereafter, a signal from a division deciding unit 7 is decided based on the value whether it is abnormal or not. When it is decided abnormal, an interrupting means 4 is operated and the passageway of the gas is closed. |
