Title:
CONTROLLER FOR MAINTAINING EXPANDED PLASTIC TUBE AT DESIRED CIRCUMFERENCE
Document Type and Number:
Japanese Patent JPS5584631
Kind Code:
A
Abstract:
Regulator for a thin film blown tubing extruder maintains prodn. control, the plant having a ring nozzle, continuous air flow internal cooling for the tubing, outlet for the used air, air urrent control, and optical sensor, devices for the position of the tubing. Devices have >=2 sensors and they alter an electrical output signal according to the wall position and any deviations from its nominal position; a controller produces a corresponding difference signal according to deviations and this signal is unaffected by cross-movement of the tubing unless the tubing circumference changes; the difference signal regulates a valve for the continuous air supply by producing a reduced tubing circumference from a reduced difference signal. Simple method is provided for maintaining constant circumference of tubing to narrow tolerances but without actually touching the material.
Inventors:
CHIYAARUZU EMU SUCHIYOTSUTO JI
JIYON JIEI MARUKAHII
JIYON JIEI MARUKAHII
Application Number:
JP15547779A
Publication Date:
June 26, 1980
Filing Date:
November 30, 1979
Export Citation:
Assignee:
GLOUCESTER ENG CO INC
International Classes:
B29C48/10; B29C49/00; B29C48/90; B29C48/92; B29C55/00; B29C55/28; G05D5/06; B29C48/355; (IPC1-7): B29D7/04