Patent ID: 6307875
Filing Date: 2001-10-23
Classification: F27B,F27D

Abstract:
A bottom tapping mechanism in an induction heating furnace, including:an inverted-hollow-cone-shaped aperture bored in a flat plate-like bottom of an accommodating vessel for accommodating therein a molten material;a funnel-shaped tapping portion comprising an inlet portion formed within said aperture and contacting an inner periphery thereof, and a hollow-pipe-like outlet portion integrally formed with and located below said inlet portion, said tapping portion being divided into a plurality of segments by a plurality of slits which are continuous to each other and connected to cooling water feed and discharge pipes;induction heating coils arranged around said taping portion at the inlet portion and the outlet portion, respectively; anda solidification-use power source portion and a melt-use power source portion connected to said induction heating coils,wherein said solid solidification-use power source portion produces a low-frequency power having a value selected for inducing eddy currents at a deep layer from the surface of the molten material so as to close the tapping portion by solidification of the molten material, andsaid melt-use power source portion produces a high-frequency power having a value selected for inducing eddy currents at a thin layer from the surface of the molten material so as to open the tapping portion by melting of the molten material.