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:
Jun. 12, 2012
Filed:
Jul. 25, 2008
Takeshi Fujita, Akita, JP;
Minoru Kanda, Akita, JP;
Takeshi Fujita, Akita, JP;
Minoru Kanda, Akita, JP;
Japan Super Quartz Corporation, Akita-Shi, JP;
Abstract
In order to provide method and apparatus for manufacturing a vitreous silica crucible with little mixing of foreign matter and stable arc during arc melting, the method and apparatus for manufacturing a vitreous silica crucible have a device which blows off air from the side of arc electrodes toward a melting space of a mold, and air discharge ports which discharge the air within the heating furnace, and perform forced supply of air into the melting space during melting to make the atmospheric pressure of the melting space higher than the surroundings, and preferably, form an air pressure difference of 100 Pa or more between the melting space and the surroundings, thereby performing melting.