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. 21, 2010
Filed:
Sep. 22, 2005
Norbert Cibis, Kahl, DE;
Oliver Ganz, Bruchkoebel, DE;
Norbert Cibis, Kahl, DE;
Oliver Ganz, Bruchkoebel, DE;
Heraeus Quarzglas GmbH & Co. KG, Hanau, DE;
Abstract
In a known method for producing tubes of quartz glass, a hollow cylinder () of quartz glass is continuously supplied to a heating zone () and is softened therein in regions, and a tube strand () is drawn off at a drawing speed from the softened region with formation of a drawing bulb (), and the tubes to be produced are cut to length in the form of tube strand pieces by separating the tube strand () at a desired separation point (T, Vu, Vo) and an internal pressure differing from the external pressure applied to the outer cladding is maintained in the inner bore () of the hollow cylinder () in that the inner bore () of the tube strand is provided with a flow obstacle. Starting therefrom to indicate a simple method which permits the manufacture of particularly large volume quartz glass tubes with utmost precision, while observing narrow tolerances, it is suggested according to the invention that the flow obstacle should be configured as a constriction () of the inner bore which is produced by softening and plastic deformation of the tube strand in the area of a deformation zone (Vu, Vo).