Method for elongating a cylinder of silica glass

US6938442B1 · kind B1 · utility

Assignee

• Heraeus Tenevo LLC · US

Inventors

• Clemens Schmitt · Walldürn, DE
• Karsten Bräuer · Bruchköbel, DE
• Uwe Christiansen · Gelnhausen, DE
• Rainer Köppler · Seligenstadt, DE
• Heinz Fabian · Alzenau, DE

Key dates

• Filing date: Mar 22, 2000
• Grant date: Sep 6, 2005
• Expiry date: Mar 22, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03B23/047
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

According to a prior art method for producing a cylindrical component comprised of silica glass, a cylinder comprised of a softened silica glass mass is drawn in a predetermined drawing direction along a drawing axis by means of a drawing device which acts upon said cylinder. The aim of the invention is to provide a method which prevents, to the greatest possible extent, warping of the drawn cylinder and other deviations from the ideal cylinder dimensions and to prevent, to the greatest possible extent, the outer surface of the drawn cylinder from being touched. To these ends, the invention provides that the drawing device comprises a plurality of guide elements which are arranged one behind the other along the drawing axis, and which can be displaced independently of one another in a drawing direction and in a direction opposite thereto. At least two of said guide elements which maintain an engaging distance from one another are simultaneously displaced, in a frictionally engaged manner, on the cylinder in a drawing direction and with an identical drawing speed. A device suited for carrying out the inventive method comprises a feed device, a heating zone and a drawing device by me…