Welding thermoplastic tubes - between paper strips around cylinder with welding clamp

摘要

In the parent patent a rotating cylinder is provided with an opening for a welding clamp which comes into contact with a thermoplastic tube passing around the cylinder in a path predetermined by the posns of two other cylinders. Contact is assured by passing the tube over a rubber conveyor belt passing around the cylinder. In the improvement of plastic tube is inserted between two paper layers in its passage between the two rollers and over the welding roll. The use of paper layers allows better adjustment of the tension than is the case with the endless belt.