Patent · US Expired

Method of and device for controlling and automatically controlling the thickness profile in the production of blown film

US6783344B1 · kind B1 · utility

19Cited by
20References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 7, 2000
Grant dateAug 31, 2004
Priority date
Expiry dateJan 17, 2021

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C2948/92923
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A device for controlling thickness of film in a blown film extruder has a blow head, a main cooling ring and an additional cooling ring. The additional cooling ring supplies separate additional air streams. A measuring and controlling device controls the thickness profile of a blown film. The measuring and controlling device scans the thickness of the blown film above a freezing zone. The device controls the additional air streams as a function of the measured blown film thicknesses. The additional cooling ring is a segmented ring arranged at the blow head of a blown film extruder adjacent the main cooling ring. A method utilizing device is likewise disclosed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.