Patent ID: 6893607

Claim:
A metal-melting furnace comprising: a main chamber; a circulation chamber connected to the main chamber by a communication passageway; a vortex well having a bottom wall with a peripheral side wall extending upwardly therefrom, the side wall having a upper edge; the vortex well further having an outlet into the main chamber; a gas bubble actuated molten metal pump having: an entry port in operative communication with the circulation chamber; and an exit port in operative communication with the vortex well; said exit port entering the vortex well through the side wall thereof; wherein the furnace is adapted to receive a quantity of molten metal within the vortex well up to a maximum height; and wherein the exit port enters the vortex well at a spaced distance from the upper edge of the vortex well and at a height at least partially above the maximum height for molten metal in the vortex well.