| 摘要 |
PURPOSE:To improve the availability of a gas burner which is suitable for use with a heater for heating road paving asphalt by a method wherein the use of both a liquefied gas and a liquid fuel such as kerosene oil is made possible such that the former is used only for ignition while the latter is used after ignition and the switching between the two is made automatically. CONSTITUTION:When a gas burner is used, a pressure adjusting valve 11 of a liquefied gas bomb 12 is opened so as to introduce the liquefied gas into a vaporization pipe 2 through a check valve 9 and a branch pipe 8. The liquefied gas is then supplied into a combustion cylinder 1 through a venturi nozzle 17 and is ignited by being injected into a combustion port 19 so that the vaporization pipe 2 is heated. Next, a valve 3 of an oil tank 4 is opened whereupon the oil flows into the vaporization pipe 2 because since a rod-shaped body 13 made of qualtz glass or the like hardly expands, the pressure contact force of a needle valve 15 with respect to a valve seat 16 becomes weak. Accordingly, the kerosene oil is vaporized instantly and is supplied to the combustion port 19 while the check valve 9 is closed due to the pressure of the vaporized gas filling the valve so that the liquefied gas is prevented from flowing into the combustion port 19 and the combustion of the burner with the kerosene oil is carried out. |
