Apparatus for controlling a pressure-type furnace for pouring molten ores

A pressure-type furnace for pouring molten metal comprising:

• a reservoir for storing said molten metal;
• an inlet passage in fluid communication with said reservoir for replenishing said molten metal;
• an outlet passage in fluid communication with said reservoir for pouring said molten metal;
• an air pressure chamber disposed above said reservoir for adjusting the level of said metal in said reservoir;
• a source of air pressure for supplying pressurized gas to said air pressure chamber;
• means coupled to said air pressure source for controlling the supply of said pressurized gas to said air pressure chamber;
• a load cell and a sampling circuit means for intermittently generating signals which are successively representative of the instantaneous amount of molten metal in said furnace;
• circuit means responsive to differences between said successive signals for generating signals representative of the rate of variation in the amount of said molten metal in said furnace;
• means for generating a reference signal representative of a specified rate of variation in the level of molten metal in said furnace;
• solenoid valve means for controlling the release of air from the pressure chamber;
• and
• comparator means responsive to said reference signal and said rate of variation signals for generating signals to operate said solenoid valve means when said rate of variation signals exceed said reference signal so that said molten metal is evenly poured when said metal is replenished.