Patent Number: 
Section: claims

1. A molten glass discharging device provided in a bottom of a melting furnace so as to control discharging of a molten material from the melting furnace, the molten glass discharging device comprising:an induction heating unit having a discharging passage along a discharging port that is formed in the bottom of the melting furnace;an induction coil provided outside the induction heating unit;a cooling unit supporting the induction heating unit and having a first cooling conduit through which a cooling fluid circulates; anda magnetic field shielding element provided outside the induction coil for shielding magnetic field,wherein the magnetic field shielding element is provided with a second cooling conduit through which a cooling fluid circulates. 2. The molten glass discharging device as set forth in claim 1, wherein the induction heating unit comprises two or more cylindrical heating elements that are symmetrically arranged along the discharging passage. 3. The molten glass discharging device as set forth in claim 1, wherein the cooling unit comprises a pair of cooling units that are symmetrically arranged on opposite lengthwise ends of the induction heating unit so that the cooling units are parallel to each other in directions perpendicular to the induction coil. 4. The molten glass discharging device as set forth in claim 1, wherein the magnetic field shielding element comprises a ferrite core.