Patent ID: 6482339
Filing Date: 2002-11-19
Classification: B29C,B29K

Abstract:
A process for stable width wise regulation of a bulb angle in extrusion of sheets of heat-sensitive plastic using an extrusion device having a calender opening formed by intake rollers, and a traversing measuring device, comprising the steps of:extruding a sheet of the sheets of heat-sensitive plastic using the extrusion devices while rotating at least one of the intake rollers; performing, at least two times, a step of measuring a parameter of the sheet of the sheets of heat-sensitive plastic correlating with the bulb angle. while moving the traversing measuring device in a width wise direction of the sheet of the sheets of heat-sensitive plastic; determining a rotational angular position of one of the intake rollers which is rotating; synchronizing said steps of measuring the parameter of the sheet of the sheets of heat-sensitive plastic with said step of determining the rotational angular position of the one of the intake rollers which is rotating such that identical measurement conditions exist in each of the steps of measuring the parameter of the sheet of the sheets of heat-sensitive plastic; and regulating a profile of the bulb angle responsive to results of each of said steps of measuring the parameter of the sheet of the sheets of heat-sensitive plastic.