| 摘要 |
PURPOSE:To make possible to detect an abnormal flame in a wide range by arranging at least one of a pair of detecting electrodes at a position contacting the abnormal combustion flame of the burner. CONSTITUTION:If the gas burner 5 causes incomplete combustion due to lack of the primary air, etc., a part of its abnormal combustion flame 6 extends and contacts a part of heat absorbing fins 3..., a DC voltage is produced by the rectifying action of the flame between the heat absorbing fine 3 of a flame detecting electrode and the gas burner 5 as a grounded electrode, and in consequence, a field effect transistor 18 obtains DC output from a detecting wire 17 and becomes OFF. Then a relay transistor 19 becomes ON making a flame detecting transistor 20 OFF and stopping the action of a safety relay 22, and thus restores a contact point 21 open. By so doing, a solenoid valve 9 closes and stops the combustion of the gas burner 5. |
