| 摘要 |
PURPOSE:To improve the reliability of monitoring of flame by a method wherein the range of the value of current, in which a burner keeps safe combustion condition, is preset while a means for judging the existence of the abnormality of a device by the changing condition of the value of current is provided in the title device. CONSTITUTION:An anode 5 and a cathode 6 are provided in the flame 4 of a burner 1 and a predetermined voltage is impressed between both electrodes to detect current conducted between both electrodes by ion in the flame 4. The range of the value of the current, in which the burner 1 keeps safe combustion condition against the change of amount of combustion or air ratio, is preset, the change of the value of the current between both electrodes 5, 6 with time is measured continuously by a current measuring instrument 9, a deciding device 10 decides that 'the flame is existing' when the value of the current is within the range, while the deciding device 10 decides that 'the combustion device is abnormal' when the value of the current has exceeded the upper limit of the range, the same device 10 decides that 'the device is abnormal' when the value of the current is lower than the lower limit of the range but the same value is not zero and decides that 'flame is absent' when the value of the current has become zero. |
