Method for the tool-free reshapingof a tubular body
US5171343A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1991 |
| Grant date | Dec 15, 1992 |
| Priority date | — |
| Expiry date | May 17, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P40/57
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process is known for the tool-free reshaping of a tubular hollow body of amorphous, especially vitreous material to a rod by pressure constriction wherein a pressure depression below atmospheric pressure is sustained in the tubular part by continual evacuation during the constriction, while the hollow body is continually fed horizontally, at a given speed of rotation, to a heating zone, and there its viscosity is so lowered that, as a result of the pressure difference between the absolute value of pressure below atmospheric pressure in the hollow body and the external pressure acting on the hollow body, the hollow body becomes constricted to form a rod in the closing zone and the rod is continually pulled from the closing zone at a given rotatory speed; in order by such a process to produce homogeneous, rod-shaped bodies from hollow bodies in a single procedure and at reasonable cost, the outside dimensions and inside dimensions of the hollow body, the viscosity of the vitreous material in the closing zone, the pressure difference between the absolute value of pressure below atmospheric pressure in the hollow body and the external pressure, the level of the pressure constriction,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.