Method for the manufacture of thermoplastic tubular members

• Main Author: LIPARI; CHARLES P
• Format: Patent
• Language: English
• Published: 18.10.1983
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BASIC ELECTRIC ELEMENTS; ELECTRICITY; PERFORMING OPERATIONS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; 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

A method for manufacturing tubular shaped thermoplastic members comprising conveying two thin sheets of thermoplastic material in close substantially parallel relationship through an ultrasonic welding station for forming a plurality of continuous spaced apart seams substantially parallel to the direction of conveying for joining the two sheets of thermoplastic material. The seams, thus formed, are cut substantially parallel to the direction of conveying such that the two sheets of thermoplastic material remain joined adjacent each side of the cuts. Preferably, the cutting takes place substantially simultaneously with the ultrasonic formation of the seams and the thin sheets of thermoplastic material are cooled prior to the ultrasonic welding. An apparatus for practicing the method is also disclosed. The method and apparatus are particularly adaptable for the manufacture of ionically permeable thermoplastic separators for use in electrochemical cells and the like.