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:
Feb. 25, 2014
Filed:
Sep. 22, 2009
Applicants:
Hiroshi Kishi, Akita, JP;
Masanori Fukui, Akita, JP;
Masaki Morikawa, Akita, JP;
Inventors:
Assignee:
Japan Super Quartz Corporation, Akita-Shi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C30B 35/00 (2006.01); C30B 11/00 (2006.01); C30B 15/00 (2006.01); C30B 21/06 (2006.01); C30B 27/02 (2006.01); C30B 28/10 (2006.01); C30B 30/04 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method of manufacturing a fused silica crucible by heating and melting a vitreous silica powder compact shaped into a mold using arc discharge of electrodes arranged around a rotation shaft of the mold, includes the steps of: arranging the electrodes in a ring shape, and setting a ratio W/R of a horizontal distance W between the electrode front end and the surface of the vitreous silica powder compact to a vitreous silica powder compact opening radius R, for at least a predetermined time during arc heating, to be in the range of 0.002 to 0.98.