| 摘要 |
PURPOSE:To provide a detecting device for lack of oxygen capable of shortening a starting time and of obtaining a big output under a normal combustion by providing small burners at both sides of a disc-type oxygen concentration cell and attaching to one of them an enclosure having a secondary air supplying port. CONSTITUTION:When a first and second small burners 2, 4 are ignited and an oxygen concentration cell is heated by exhaust gas of flames 4A, 2A, an electrode 12 contacts with an atmosphere containing excess oxygen while an electrode 13 contacts with an atmosphere containing insufficient oxygen, therefore, an electromotive force is created in the cell and the internal resistance thereof is decreased. If a density of oxygen in air is decreased at this time, the flame 2A moves to an upper portion of an enclosure 3 as shown by a flame 2B and provide the electrode 12 with an atmosphere lacking oxygen. Thereby, a density ratio of oxygen in atmospheres contacting with both electrodes 12, 13 is decreased suddenly and the electromotive force also is decreased quickly in stepwise. Consequently, the electromotive force of the oxygen concentration cell may be rapidly decreased due to a density of oxygen in air when oxygen is lacked in air. |
