| 摘要 |
PURPOSE:To detect exactly a molten metal surface of a molten object by installing an inert gas supplying nozzle to a prescribed position of a furnace body, and installing a path for cooling and a shielding gas, to the outside circumferential part of the nozzle. CONSTITUTION:An upper furnace body 2 is placed on the upper part of a crucible 1 of a microwave heating furnace, and on its lower flange 10, a path 3 for an inert gas is formed. Also, one end part of this path 3 is connected to a nozzle 7 installed so as to face the inside of the crucible 1, and the other end part is connected to a back pressure detecting system pipe 4. In this state, when the molten metal surface reaches the nozzle 7, a rise of a back pressure is detected and the molten metal surface is detected, and also the inert gas is supplied into the crucible 1 so as to prevent overheating of the nozzle and adhesion of dust, etc. to the nozzle. In this way, the molten metal surface of a molten object can be detected exactly. |
