System for indicating the liquid level in a continuous-casting mold or the like

Claim 1

A SYSTEM FOR INDICATING THE HEIGHT OF THE LIQUID LEVEL IN A CONTAINER WHEREIN THE TEMPERATURE OF SAID LIQUID DIFFERS FROM THE AMBIENT TEMPERATURE ABOVE SAID SURFACE, COMPRISING: (A) A FIRST SET OF THERMOCOUPLES, EACH THERMOCOUPLE OF SAID FIRST SET BEING IN THERMAL CONTACT WITH A SEPARATE ONE OF A FIRST SET OF POINTS SPACED VERTICALLY WITHIN SAID CONTAINER, (B) A FIRST SLIDE-WIRE RESISTOR, (C) THE NEGATIVE TERMINAL OF EACH ONE OF SAID FIRST SET OF THERMOCOUPLES BEING CONNECTED TO A SEPARATE POINT ALONG SAID FIRST RESISTOR, THE SET OF SAID POINTS ALONG SAID FIRST RESISTOR BEING SPACED TO CORRESPOND TO THE SPACING BETWEEN SAID FIRST SET OF POINTS WITHIN SAID CONTAINER, (D) A SECOND SET OF THERMOCOUPLES, EACH THERMOCOUPLE OF SIAD SECOND SET BEING IN THERMAL CONTACT WITH A SEPARATE ONE OF A SECOND SET OF POINTS SPACED VERTICALLY WITHIN SAID CONTAINER, (E) A SECOND SLIDE-WIRE RESISTOR, (F) THE POSITIVE TERMINAL OF EACH ONE OF SAID SECOND SET OF THERMOCOUPLES BEING CONNECTED TO A SEPARATE POINT ALONG SAID SECOND RESISTOR, THE SET OF SAID POINTS ALONG SAID SECOND RESISTOR BEING SPACED TO CORRESPOND TO THE SPACING BETWEEN SAID SECON SET OF POINTS WITHIN SAID CONTAINER, WHEREBY A CONTINUOUS VOLTAGE PROFILE IS OBTAINED ALONG EACH OF SAID SLIDE-WIRE RESISTORS THAT IS AN ANALOG TO THE VERTICAL TEMPERATURE PROFILE WITHIN SAID CONTAINER, (G) MEANS TO BIAS ONE OF SAID SET OF THERMOCOUPLES RELATIVE TO THE OTHER OF SAID SET OF THERMOCOUPLES WHEREBY THE VOLTAGE ALONG SAID FIRST VOLTAGE PROFILE AT SAID LIQUID LEVEL WILL EQUAL THE VOLTAGE ALONG SAID SECOND VOLTAGE PROFILE AT SAID LIQUID LEVEL, (H) A FIRST CONTACT ELECTRICALLY ENGAGING SAID FIRST RESISTOR AND MOVABLE ALONG SAID FIRST RESISTOR, (I) A SECOND CONTACT ELECTRICALLY ENGAGING SAID SECOND RESISTOR AND MOVABLE ALONG SAID SECOND RESISTOR, (J) SAID CONTACTS BEING MECHANICALLY GANGED TOGETHER SO THAT BOTH OF SAID CONTACTS ARE ELECTRICLALY CONNECTED TO COMPARABLE POSITIONS ALONG THE RESPECTIVE VOLTAGE PROFILES PROVIDED BY THE RESPECTIVE ONES OF SAID SLIDE-WIRE RESISTORS, AND (K) MOTOR MEANS CONNECTED TO DRIVE SAID CONTACTS AND RESPONSIVE TO THE VOLTAGE DIFFERENCE BETWEEN SAID CONTACTS TO DRIVE SAID CONTACTS TO A POSITION ALONG SAID RESISTORS WHERE THE VOLTAGE AT ONE OF SAID CONTACTS WILL EQUAL THE VOLTAGE AT THE OTHER OF SAID CONTACTS, WHREBY THE REST POSITION OF SAID CONTACTS ALONG SAID RESISTORS WILL CORRESPOND TO THE LIQUID LEVEL.