Longitudinal sealer for bag making and filling machine

摘要

As a cylindrically formed web of thermoplastic bag-making material is transported longitudinally along a path at a specified speed (Vf), a longitudinal sealer with a heater (5) is compressed against and over portions of the material parallel to the path to effect longitudinal sealing. The longitudinal sealer is moved in the meantime along the path at a greater speed (Vh) in the range of 1.05 to 1.30 times the specified speed of motion of the material such that generation of V-shaped wrinkles known as the chevrons on both sides of the sealed area can be prevented.