Patent ID: 6997234
Filing Date: 2006-02-14
Classification: B22D

Abstract:
1. A method of enhanced gravity casting comprising: directing a charge of molten lead into a chamber located in fluid communication with a battery part cavity; allowing the battery part cavity to fill with molten lead under a gravity flow condition; forming the shutoff member with a dimension less than the dimensions of the chamber so that when the shutoff member is in the closed condition the molten lead remains in a molten state around the shutoff member extending the shutoff member located in the molten lead in the chamber into engagement with a mold inlet passage while the molten lead is in a liquid state to close off the inlet passage and prevent further gravity flow of molten lead into the mold cavity; and maintaining a following force to generate sufficient pressure on the shutoff member as the molten lead solidifies to allow the shutoff member to follow a volume contraction of the molten lead in the mold cavity to thereby form an enhanced gravity casting.