APPARATUS FOR IN-LINE MEASUREMENT OF DEGREE OF ORIENTATION OF FILM/SHEET

• Main Authors: YONETANI HIDEO, MIKI TOSHIRO
• Format: Patent
• Language: English
• Published: 02.03.1992
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PURPOSE:To perform the optimizing control of a molding condition, the quality control of a product, the foreknowledge of breakage and the detection of foreign matter by monitoring a degree of orientation by allowing a film/sheet to run between polarizers to measure the quantity of double refraction of the film/sheet according to an in-line system. CONSTITUTION:The resin molten by an extruder 1 is extruded from an automatic die 2 to become a sheet-like state and the extrudate is cooled and solidified by a casting machine 3 to be molded into a raw sheet. The raw sheet is biaxially stretched in both of a line direction and a film lateral direction in succession by longitudinal and lateral stretching machines 4, 6 to be taken up by a taking-up winder 8. Herein, degree-of-orientation meters 5, 7 are operated in the film lateral directions to respectively measure the degrees of orientation of the film after longitudinal stretching and lateral stretching and a stretching condition is controlled by a main control apparatus 11.