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:
Sep. 24, 2002
Filed:
Oct. 29, 1999
George D. Chandley, Amherst, NH (US);
Qi Zhao, Nashua, NH (US);
Hitchiner Manufacturing Co., Inc., Milford, NH (US);
Abstract
A vaporizable refractory coated pattern assembly is formed having a sprue connected to a plurality of thin wall patterns of articles to be cast. The pattern assembly is supported in a refractory particulate media in an open bottom container that is evacuated to subambient pressure and rotated in a manner to distribute particulates to regions of the refractory coated patterns not yet directly contacted by particulates. The pattern assembly is comprised of relatively dense foam plastic pattern material that imparts increased strength to the thin wall patterns. The sprue includes a vent passage that communicates to a particulate media to vent pattern decomposition vapors thereto in a manner that enables faster replacement of the pattern assembly in the media, despite the use of the relatively dense pattern material.