Patent ID: 6845810

Claim:
Gravity Lost Foam casting apparatus for shaping an aluminum casting alloy into a desired shape comprising: (1) a bed of loose sand forming a mold having a molding cavity therein conforming to said shape; (2) a flask containing said bed; (3) a fugitive pattern embedded in said bed and shaping said molding cavity, said pattern comprising a polymeric foam pyrolizable by molten said casting alloy poured into said molding cavity; (4) a fugitive body attached to said pattern and forming a gating system in said bed for supplying said molten casting alloy to said molding cavity, (5) an inlet to said gating system for admitting molten casting alloy into said gating system; and (6) a hollow metallic sprue embedded in said bed adjacent said pattern for supplying said molten casting alloy to said inlet, wherein said metallic sprue consists of an aluminum sprue-forming alloy that is recyclable with a melt of such of said casting alloy as solidifies in said sprue following casting to reconstitute said casting alloy for future casting without first having to remove any undesirable ceramic or alloyant materials that might otherwise have been carried into said melt by said sprue.