| 摘要 |
PURPOSE:To improve responsiveness to shortage of oxygen and combustive stability by a method wherein the outer flame hole part of a separating flame sensor is placed under a pilot burner flame hole part and a combustion detecting element is provided facing the inner flame hole part of the separating flame sensor. CONSTITUTION:An electromagnetic valve 15 is opened and fired by firing operation. The inner flame 3 is kept by the balance between the injection speed and the combustion speed of mixed gas and is sensitive to the change of concentration of oxygen. Therefore, when oxygen becomes short and takes a set concentration the inner flame 3 lifts and moves toward an upward outer flame 4. Therefore, an electrical heating element 5 stops heating, an electromagnetic valve 15 is demagnetized and a gas circuit is blocked. It is safe that the lift point of te inner flame 3 is set just before CO occurs out of the main burner 11. The inner flame 3 is placed in the outer cylinder 2 and so stability for the wind etc. can be improved. Thus, responsiveness to shortage of oxygen, combustion stability can be improved. |
