Patent · US Expired

Method and apparatus for controlling the thickness of extruded stock

US4088721A · kind A · utility

19Cited by
9References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 24, 1976
Grant dateMay 9, 1978
Priority date
Expiry dateSep 24, 1996

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29D2030/4456
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The thickness of a cut length of a continuously extruded elastomer is controlled by sampling the weight of a section of the continuous extrusion at a running-weigh-scale each second; computing and storing one-minute averages of the running-weigh-scale samples; sampling the weight of a cut length of the extrusion at a check-weigh-scale; comparing the check-weigh-scale value to the oldest stored running-weigh-scale one-minute average to obtain a targeted average; comparing the targeted running-weigh-scale average to the newest stored running-weigh-scale one-minute average to obtain a deviation from the targeted value if one exists; and converting the deviation from the targeted running-weigh-scale value to a control signal for increasing or decreasing the speed of a take-away belt positioned at the extruder exit orifice to vary the thickness of the extrusion in accordance with the deviation control signal and the speed of the belt.

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