摘要 |
PURPOSE:To prevent backfire and explosion when lighting and extinguishing the flame in an atomic absorptiometric analyzer and improve its safety by increasing the quantity of acetylene supply so that the flame is once in the complete combustion state and the combustion speed is lowered, and switching the flame in accordance with the intensity of the flame. CONSTITUTION:To light a burner B; with solenoid valves V1 and V3 opened simultaneously, the air-acetylene flame is ignited. When the air supply is changed over to the dinitrogen oxide supply, acetylene is supplied excessively. A comparator A2 compares the output of a solar cell C, which corresponds to the intensity of the flame, with a reference voltage, and the output of the comparator A2 is inputted to a control circuit to control the operation of solenoid valves V1, V2 and V4. |