Air cooling ring for plastic film with independent lubricating air for film guide surface
US4272231A · kind A · utility
24Cited by
5References
4Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 15, 1979 |
| Grant date | Jun 9, 1981 |
| Priority date | — |
| Expiry date | Mar 15, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/912
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Air ring for cooling a hot extruding tube of plastic film in which a lubricating air bleed port communicates with air from the air ring plenum independent of the cooling air flow path. The bleed port communicates with a bleeded air passage that extends to an annular lubricating air outlet positioned in advance of a guide surface that precedes the cooling air outlet. In an exterior air ring a valve arrangement limits the bleeded flow to the minimum desired.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.