The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 16, 1997
Filed:
May. 05, 1994
Jamal Righi, Murrysville, PA (US);
James R Fields, Export, PA (US);
Eric D Arndt, New Kensington, PA (US);
Aluminum Company of America, Pittsburgh, PA (US);
Abstract
A vacuum die-casting machine has a sprue cavity with sufficient depth facing the shot cylinder that the shot cylinder piston can easily crush with a pressure of less than 1000 psi the thin cylindrical shell of solidified metal which develops into the biscuit, and continue to advance after the die cavity becomes fried with molten metal to inject additional molten metal into the die cavity to make up for shrinkage porosity as the cast part cools. The runner through which the molten metal passes from the sprue cavity into the die cavity has generally spherical reservoirs adjacent circular gates to further assure the supply of the additional molten metal to make up for shrinkage in the part. In addition, the piston can be oil cooled steel to delay formation of the biscuit.