COMBUSTION DEVICE

PROBLEM TO BE SOLVED: To provide a combustion device comprising a secondary air supply passage at an outer part of a burner head, and surely preventing the combustion loss by effectively cooling a burner head ring. SOLUTION: This combustion device comprises a burner head ring 46 mounted between the burner head 24 and an outer cylinder 48 in a state of covering the circumference of a lower part of the burner head 24 in the ring shape, a main burner port 25 is formed on an upper face of the burner head 24, an auxiliary burner port 27 is formed on a side face peripheral wall of the burner head 24 for taking the heat back by the burner head ring 46, the secondary air supply passage 49 is formed between the outer cylinder 48 and the burner head ring 46 to supply the secondary combustion air to a combustion part at an upper part of the main burner port 25, and an opening hole 54 for cooling the burner head ring 46 is formed on a position opposite to the burner head ring 46 on the way of the secondary air supply passage 49, whereby the burner head ring is effectively cooled by a part of the secondary combustion air, and the combustion loss can be surely prevented. COPYRIGHT: (C)2004,JPO&NCIPI