| 摘要 |
PURPOSE:To improve operability at firing in the combustor of the safety controller for the combustor such as gas implements which include a discharge igniter and an electromagnetic valve to be controlled by a thermocouple by making use of a timer circuit to be triggered by electric discharge to open the electromagnetic valve. CONSTITUTION:When a return electromagnetic valve 20 is opened by hand after a gas cock 33 is opened and power source 23 is connected, gas is ignited by the discharge electrode 13 and at the same time a pulse current flows from a high voltage code 15 to a coil 16, so that a transistor Tr3 is turned off for a certain time. Thereby a transistor Tr18 is turned on for a certain time and a transistor Tr19 is turned on so that current is fed to the electromagnetic valve 20 for a certain time. Accordingly, even when the manual operation of the electromagnetic valve 20 discontinues, the valve 20 is maintained in the opened state for a certain time so as to heat the thermocouple 32 on the burner surface. The flame signal outputted from the thermocouple 32 is inputted through operation amplifier 25 into transistor Tr19 to turn on the same and the electromagnetic valve 20 is maintained in an opened state. |
