Apparatus for smelting metals

Claim 1

APPARATUS FOR MELTING AND REFINING METALS SUSCEPTIBLE TO RAPID OXIDATION AT ELEVATED TEMPERATURES, WHICH COMPRISES A FURNACE HAVING REFRACTORY LINED SIDE, TOP, AND BOTTOM WALLS DEFINING A RELATIVELY LARGE, ENCLOSED, MAIN HEARTH AND REFRACTORY LINED SIDE AND BOTTOM WALLS DEFINING A RELATIVELY SMALL, OPEN, AUXILIARY HEARTH, SAID HEARTHS BEING OF SUBSTANTIAL DEPTHS FOR HOLDING BATHS OF MOLTEN METAL AND THE BOTTOMS OF SAID HEARTHS BEING AT SUBSTANTIALLY THE SAME LEVEL, MEANS FOR SUPPLYING HEAT TO METAL ON THE MAIN HEARTH FOR MAINTAINING IT IN A MOLTEN CONDITION, A FIRST PASSAGE CONNECTING SAID HEARTHS SUBSTANTIALLY AT THE LEVEL OF THEIR BOTTOMS TO PERMIT FREE FLOW OF MOLTEN METAL FROM ONE TO THE OTHER, THE VERTICAL HEIGHT OF SAID PASSAGE BEING SUBSTANTIALLY LESS THAN THE DEPTHS OF SAID HEARTHS FOR MAINTAINING SAID PASSAGE ENTIRELY BELOW THE NORMAL LEVEL OF MOLTEN METAL ON THE HEARTHS, A PUMP FOR MOLTEN METAL, A SECOND PASSAGE COMMUNICATING AT ONE END WITH SAID MAIN HEARTH THROUGH AN OPENING DISPOSED SUBSTANTIALLY AT THE LEVEL OF THE BOTTOM THEREOF AND HAVING A VERTICAL HEIGHT SUBSTANTIALLY LESS THAN THE DEPTHS OF SAID HEARTHS, WHEREBY SAID OPENING MAY BE MAINTAINED ENTIRELY BELOW THE LEVELS OF MOLTEN METAL ON THE HEARTHS, SAID SECOND PASSAGE BEING ASSOCIATED WITH THE INTAKE OF SAID PUMP FOR SUPPLYING MOLTEN METAL THERETO FROM SAID MAIN HEARTH, AND A THIRD PASSAGE COMMUNICATING AT ONE END WITH THE DISCHARGE OF SAID PUMP AND EXTENDING ABOVE THE AUXILIARY HEARTH FOR RECEIVING MOLTEN METAL FROM SAID PUMP AND DISCHARGING IT DOWNWARDLY AS A FREELY FALLING STREAM INTO A BATH OF MOLTEN METAL ON THE AUXILIARY HEARTH.