ELECTRIC BOOSTING CONTROL FOR A GLASS FOREHEARTH

摘要

ABSTRACT OF THE DISCLOSUREApparatus for heating molten glass flowing througha conditioning section of a forehearth has pairs of electrodesextending through the sidewalls of the forehearth with theirends terminating adjacent the sidewalls and a circuit connect-ed to the electrode pairs and being such as to cause jouleeffect heating of the glass adjacent the sidewalls of theforehearth, with a source of electrical current connectedto the circuit. A first temperature sensor within the fore-hearth at the center line thereof within the conditioningsection adjacent an end thereof has a thermocouple immersedin the glass and a second temperature sensor extending intothe forehearth adjacent one of the sidewalls thereof in align-ment with the first sensor, a settable, temperature overridecircuit connected to the circuit means. The second tem-perature sensor is connected to a settable temperature over-ride circuit for adjusting the current to the electrodesto bring the sidewall temperature to the selected set pointof the override circuit.