| 摘要 |
PURPOSE:To prevent the occurrence of natural ignition in a burner head and backfire phenomenon and to increase a varying range of a combustion amount, by a method wherein a burner cap is formed in a 2-stage structure through the medium of a space, and a secondary air port is formed in the outer peripheral surface of a burner head. CONSTITUTION:Fuel fed to the interior of an evaporating cylinder 9 is heated and evaporated on the evaporating cylinder 9 heated by a heater, is mixed with primary air, and fed through a throttle part 11 to an internal space of a burner head 1. In this case, the velocity of flow of gas is increased by a throttle part 10, injected gas is forced into collision contact with the under surface of a lower burner cap 4, is diffused in the burner head 1, and is injected through pores 3 to the outer surface of the burner head to form flame. The lower burner cap 4 is cooled by means of secondary air, and since the cap is protruded from the inner surface of the burner head, the temperature of fuel-air premixture decreases, and there is less risk of the premixture being naturally ignited. The flow of secondary air fed through a secondary air feed pipe 7 is straightened, the air is preheated in a secondary air chamber 8 and injected through a secondary air port 6 to the inner peripheral surface of flame, and is mixed with an unburnt gas component in the vicinity of the inner peripheral surface of flame to promote combustion. |
