Patent ID: 6045251
Filing Date: 2000-04-04
Classification: B29C

Abstract:
A method of controlling a sheet profile for bank formation using a system including a die and two rotational formation rolls arranged substantially to be parallel to each other at a downstream side of the die, in which a plastic material heated and plasticized is fed through a discharge port of the die in shape of sheet to an upstream side of a gap between the two formation rolls and a sheet is formed so as to provide a predetermined sheet profile by passing through the gap between the two rolls under pressure while forming a bank of the plastic material at the upstream side of the roll gap, the sheet profile control method comprising the steps of:measuring a bank profile of the bank formed to an upstream side of the roll gap and a sheet profile of a sheet fed out through the roll gap;operating a deviation between the measured sheet profile and an aimed sheet profile;operating an aimed bank profile corresponding to the aimed sheet profile from the measured bank profile and the operated deviation;operating another deviation between the aimed bank profile and the measured bank profile, andadjusting a discharge amount distribution of the plastic material at the discharge port of the die so as to eliminate the another deviation and control the sheet profile so as to have a uniform shape.