Patent · US Expired

Method and an apparatus for the continuous crimping of thermoplastic threads

US5351374A · kind A · utility

14Cited by
14References
24Claims
0Family size

Inventors

Key dates

Filing dateFeb 4, 1993
Grant dateOct 4, 1994
Priority date
Expiry dateFeb 4, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N33/365
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Threads made from thermoplastic materials are textured, in that they are heated by a delivery medium in a delivery channel and conveyed through an orifice into a stuffer box where they are stuffed to form a plug. In order to maintain plug formation constant, the orifice area is monitored in a sensory manner and the measured signals are used for monitoring purposes as a measured quantity in a control loop, in which the supply of damming back medium, the conveying away speed of the plug, the position of the stuffer box walls, or the supply of delivery medium are used as manipulated variables. The measuring signals produced by monitoring can be compared with thresholds to produce control signals corresponding to the comparison result for activating alarm, warning or stopping elements. Sensory monitoring is carried out by measuring the dynamic pressure prevailing in the delivery channel close to the orifice, by measuring the dynamic pressure in a fluidic nozzle issuing into the stuffer box, or by monitoring with an optical sensor the interior of the stuffer box.

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