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:
Nov. 22, 2011
Filed:
May. 11, 2006
Thomas Bogdahn, Karlstein, DE;
Thomas Bogdahn, Karlstein, DE;
Heraeus Quarzglas GmbH & Co. KG, Hanau, DE;
Abstract
In a known method for producing a tube of quartz glass by elongating a hollow cylinder of quartz glass having an outer diameter AD, said cylinder is continuously supplied to a heating zone with a vertically oriented heating tube having an inner diameter d, with the proviso that the diameter ratio d/AD is set to a value ranging from 1.02 to 1.7. The hollow cylinder is softened therein zonewise, and a tubular strand is drawn off from the softened region and shortened to obtain the tube. Starting therefrom, in order to optimize the dimensional stability of the quartz glass tube obtained, it is suggested according to the invention that the heating zone should have a length L which is set such that the ratio L/d is smaller than 0.9.