Method of and apparatus for tubularly drawing thermoplastic resin
US4869863A · kind A · utility
5Cited by
8References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1988 |
| Grant date | Sep 26, 1989 |
| Priority date | — |
| Expiry date | Aug 31, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2793/0063
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The present invention relates to a method and an apparatus for tubularly drawing a tubular raw material of thermoplastic resin. Gas for forming a bubble to heatingly draw the tubular raw material is injected into the raw material from a direction opposite to a direction for transferring the raw material through a nozzle. The raw material is cut into a plurality of web-like pieces by cutting blades provided on pinch rolls for taking up the raw material. One of the web-like pieces thus cut is separated from the others and formed with an opening into which the nozzle is inserted to inject the gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.