METHOD AND APPARATUS FOR DRAWING FILM

• Main Authors: JOHN JOSEPH KEEGAN JR, WILLIAM JOHN HOMMES
• Format: Patent
• Language: English
• Published: 14.01.1993
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CONVEYING; HANDLING THIN OR FILAMENTARY MATERIAL; HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS,CABLES; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; PACKING; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; STORING; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

Apparatus and method for producing a novel drawn film by propelling individual carriages along opposed loops from a first speed abutted in stacks in carriage collection sections to a second speed space apart in a drawing section of a tenter frame and to a third speed in stack forming sections where the carriages return to the first speed in the stacks. First primaries positioned adjacent one part of each loop develop electromagnetic waves for engaging synchronous secondaries attached to active carriages to provide controlled spacing of such carriages, and second primaries adjacent another part of the loop develop other electromagnetic waves for engaging hysteresis secondaries attached to active and to passive carriages to provide controlled abutting of the carriages.