Arc furnace electrode control apparatus

Claim 1

MEANS FOR CONTROLLING AN ARC FURNACE ELECTRODE IN RELATION TO A BODY OF FURNACE CHARGE, COMPRISING A BYDRAULIC MOTOR, A RESERVOIR OF HYDRAULIC FLUID, ELECTRORESPONSIVE PUMP MEANS HAVING AN OUTPUT CONNECTED TO SAID HYDRAULIC MOTOR AND AN INPUT COUPLED TO SAID RESERVOIR, CONDUIT MEANS COUPLING SAID HYDRAULIC MOTOR TO SAID RESERVOIR, NORMALLY CLOSED ELECTRORESPONSIVE VALVE MEANS IN SAID CONDUIT MEANS FOR PREVENTING THE DISCHARGE OF SAID FLUID FROM SAID MOTOR TO SAID RESERVOIR, CIRCUIT MEANS COUPLED TO SAID ELECTRODE FOR PRODUCING A FIRST OUPUT SIGNAL WHEN THE DISTANCE BETWEEN SAID ELECTRODE AND SAID CHARGE BECOMES TOO SMALL AND FOR PRODUCING A SECOND OUTPUT SIGNAL WHEN THE DISTANCE BETWEEN SAID ELECTRODE AND SAID CHARGE BECOMES TOO LARGE, MEANS COUPLED TO SAID CIRCUIT MEANS AND OPERABLE UPON THE OCCURRENCE OF SAID FIRST SIGNAL TO ENERGIZE SAID ELECTRORESPONSIVE PUMP MEANS TO DRIVE SAID ELECTRODE UPWARDLY AND OPERABLE UPON THE OCCURRENCE OF SAID SECOND SIGNAL TO ENERGIZE SAID ELECTRORESPONSIVE VALVE MEANS SO THAT SAID VALVE MEANS IS ACTUATED TO AN OPEN POSITION TO CONNECT SAID FLUID MOTOR TO SAID SUMP AND ALLOW SAID ELECTRODE TO LOWER, SAID LAST MENTIONED MEANS BEING OPERATIVE TO DE-ENERGIZE SAID PUMP MEANS OR SAID VALVE MEANS UPON THE DISSAPPEARANCE OF SAID FIRST AND SECOND SIGNALS RESPECTIVELY.