Patent DE-102008029756-B3 (DE)
Title: Producing cylinder made of quartz glass for producing preforms for optical fibers, comprises depositing silicon dioxide particle on longitudinal carrier under formation of soot bodies, and maintaining the soot in furnace by sinter process
Inventor: SOWA RENE
IPC: C03B37/018
Filed: 2008-06-25
Granted: 2009-04-30
Abstract: The method for producing a cylinder made of quartz glass for producing preforms for optical fibers, comprises depositing silicon dioxide particle on a longitudinal carrier under formation of a porous, hollow cylindrical soot bodies, where the carrier rotates around a rotation axis, and maintaining the soot bodies in vertical adjustment in a furnace by a sintering process, in a suspended manner, where the soot bodies comprise an inner bore (11) with an inner wall (7), a longitudinal axis, an upper- and a lower end. A holding element (2) is intended in the inner bore. The method for producing a cylinder made of quartz glass for producing preforms for optical fibers, comprises depositing silicon dioxide particle on a longitudinal carrier under formation of a porous, hollow cylindrical soot bodies, where the carrier rotates around a rotation axis, and maintaining the soot bodies in vertical adjustment in a furnace by a sintering process, in a suspended manner, where the soot bodies comprise an inner bore (11) with an inner wall (7), a longitudinal axis, an upper- and a lower end. A holding element (2) is intended in the inner bore and engaged at a bridging bearing intended in the inner bore. The bridging bearing is provided with bridging elements (5) movable against the inner wall. The bridging element carries out a movement with a movement component under the effect of the holding element in the direction perpendicular to the longitudinal axis of the soot bodies and is pressed against the inner wall. The holding element comprises a lower sliding surface, which protrudes the bridging element. The lower sliding surface is formed as outer cone (3) of the holding element. The bridging element comprises an upper sliding surface cooperating with the lower sliding surface. The lower- and the upper sliding surfaces run from top to bottom view toward the inner wall in a wedge angle of 60 degrees to the longitudinal axis. The upper sliding surfaces form a downwardly opened inner cone of the bridging bearing. The bridging element comprises friction face, which extends parallel to the inner wall and is pressed against the inner wall in the movement in the direction perpendicular to the longitudinal axis, and an upper side, on which a ring element made of quartz glass is present. The ring element has an outer diameter of 10 mm smaller than the inner diameter of the inner bore. The holding element projects with a longitudinal section in the inner bore, where a part of the longitudinal section is surrounded by a protective cover made of quartz glass. The bridging bearing and the holding element consist of quartz glass. The bridging element carries out the movement under effect of the holding element and the weight of the soot bodies. An independent claim is included for a holding device for the production of a cylinder made of quartz glass.