Patent ID: 7892319
Filing Date: 2011-02-22
Classification: C25C

Abstract:
1. A crust breaker and ore feeder device for an aluminum smelting pot that contains a molten electrolyte in which aluminum ore is dissolved for electrolytic reduction into aluminum metal, the device being of the type in which a vertical shaft is positioned above the molten electrolyte for axial vertical motion, and which has a crust breaker chisel mounted at a lower end thereof for breaking a crust that forms on an upper surface of the molten electrolyte, and has an ore dispenser situated over said shaft, in which an upper closure is open when the shaft is fully raised to admit ore into the dispenser from an ore hopper and closes when the shaft is lowered; and a dispensing valve that releases the ore from the dispenser when said shaft is lowered; and a pneumatic cylinder for controllably raising and lowering said shaft to dispense said ore and to break said crust; and comprising the improvement wherein said pneumatic cylinder comprises a) an in-line three-position pneumatic cylinder capable of moving the shaft to a fully raised position, to a fully lowered position, and to an intermediate, partly lowered position; and b) a pneumatic control for applying compressed gas thereto, such that the cylinder can provide a full stroke to move the shaft from the full raised position to the fully lowered position to perform an ore dispensing operation and a crust breaking operation; a partial stroke between the fully raised position and the intermediate position to perform an ore dispensing operation without a crust breaking operation; and a partial stroke between said intermediate position and said fully lowered position to perform a crust breaking operation without an ore feeding operation.