Patent ID: 7343761

Claim:
A device for producing a glass rod, comprising: a Danner blowpipe having a jacket surface defining a supply end and a discharge end; and a nozzle for introducing a glass stream onto the jacket surface at the supply end so that a glass film forms and is taken up at the discharge end, wherein the Danner blowpipe has an outer metal jacket and a ceramic body surrounded by the outer metal jacket, a clamping plate is provided at the supply end and a clamping plate is provided at the discharge end so that a displacement path is defined between the clamping plate at the discharge end and the ceramic body, the clamping plate on the discharge end is rigidly joined with a shaft and engages the outer metal jacket at the discharge end and the clamping plate on the supply end is joined in an axially displaceable manner on a supply-side of the shaft, which is rigidly joined with a pressure plate against displacement in an axial direction, and a pressure spring disposed between the pressure plate and the clamping plate on the supply end and presses the pressure plate and the clamping plate away from one another, wherein the outer metal jacket extends from the discharge end only over a part of a length of the ceramic body.