| 摘要 |
<p>PCT No. PCT/SE96/00811 Sec. 371 Date Mar. 9, 1998 Sec. 102(e) Date Mar. 9, 1998 PCT Filed Jun. 20, 1996 PCT Pub. No. WO97/00835 PCT Pub. Date Jan. 9, 1997Methods of plastically forming an axially extended zone of the interior surface of a hollow glass tube heated to its forming temperature employ a generally cylindrical embossing mandrel connected to a driving shaft. The hollow glass tube and the embossing mandrel are brought together at a predetermined start position for the embossing mandrel inside the glass tube and are brought into contact in an area in which the zone is to be formed on the interior surface of the glass tube. A relative rolling off planetary motion between the embossing mandrel and the glass tube is provided while plastically forming the zone of the glass tube and creating depressions therein. The rolling off planetary motion is achieved by (i) rotating the embossing mandrel around the longitudinal axes of the embossing mandrel and the glass tube, (ii) rotating the embossing mandrel around its longitudinal axis and rotating the glass tube around its longitudinal axis, or (iii) rotating the glass tube around the longitudinal axes of the glass tube and the embossing mandrel. The glass tube and embossing mandrel are then separated.</p> |
