Patent · US Expired

Method and apparatus for controlling the thickness of extruded stock

US4156913A · kind A · utility

12Cited by
6References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 5, 1978
Grant dateMay 29, 1979
Priority date
Expiry dateMay 5, 1998

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 one-minute averages of the running-weigh-scale samples and storing "A" to "n" of the averages where "A" is the newest and "n" is the oldest stored average; sampling the extruder motor power draw each second; computing one-minute averages of the power draw and storing "B" to "m" of the averages where "B" is the newest and "m" is the oldest stored average; comparing the newest to the oldest power draw average to obtain a difference between the two and multiplying the difference by a constant indicative of the type of elastomeric material being processed through the extruder to obtain a power-draw deviation signal; sampling the weight of a cut length of material extrusion at a check-weigh-scale; comparing the check-weigh-scale value to the oldest "n" stored running-weigh-scale one-minute average and to the power draw deviation to obtain a targeted running-weigh-scale average; comprising the targeted running-weigh-scale average to the newest "A" stored running-weigh-scale one-minute average to ob…

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