Transverse sealer

摘要

A bag maker bends an elongate flexible bag-making film (f) into a tubular form and transversely seals it by a transverse sealer (110) while filling it with articles to produce packaged bags. The transverse sealer (110) has two seal jaws (1) at both sides of the film being pulled downwards. The seal jaws (1) are each caused to move in a generally D-shaped trajectory with a vertically straight portion where they move along the film, sandwiching it therebetween. The seal jaws are operated so as to move faster than the film while on the top half of the straight portion of the trajectory where stripping takes place and more slowly than the film while on the bottom half of the straight portion such that the film will blouse to make it easier for articles to drop deeper inside the bag being produced. The speed of each seal jaw on the arcuate part of its trajectory is adjusted such that the period of the cyclic motion of the seal jaws need not be modified.