Air cooling ring for plastic film
US4750874A · kind A · utility
17Cited by
10References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 9, 1987 |
| Grant date | Jun 14, 1988 |
| Priority date | — |
| Expiry date | Jan 9, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/912
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A dual flow air ring is used to cool the exterior surface of thermoplastic tube after the plastic is extruded from an annular die. The surface of the wall forming the divider between the upstream and downstream flow paths which confronts the extruded tube is shaped to include a region of decreasing diameter in the direction of tube travel so that the flow path for air issuing from the lower discharge formed between the extruded tube and the surface is caused to converge. This converging flow stabilizes the tube thereby permitting more vigorous cooling and consequently higher production rates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.