| 摘要 |
PURPOSE:To close a gas flow passage against other types of abnormal conditions by a method wherein a voltage output type sensor for varying an output voltage when a leakage of gas is detected and a non-voltage output type sensor for detecting an abnormal condition through only driving a switch element are simultaneously connected. CONSTITUTION:To the terminals T1 and T2 are connected sensors such as non-voltage output type flame sensors. When a gas leakage is occurred, a sole noid 9 is operated under an output from a gas leakage sensor 1 and a gas flow passage isclosed. In turn, if a flame sensor is connected to the terminals T1 and T2, a line between the terminals T1 and T2 is short circuited when the flame is generated, a resistance value at a high voltage at a voltagedividing part 4 is increased, so that if the resistor R4 is set to a desired value, the first transistor Q1 is turned ON and the solenoid 9 is operated to clost the gas flow passage. |
