SEALER APPARATUS FOR PLASTIC FILM PROCESSING INCLUDING AN ADJUSTABLY MOUNTED SEAL BAR, PARTICULARLY FOR BAG MAKING MACHINES

摘要

A cross sealer for a plastic bag making machine includes a frame with anupper moveable seal bar unit and an opposed lower stationary seal bar unit.Themovable unit is a lightweight construction seal beam. A rotating shaft spansthe crosssealer and is connected by a plurality of eccentric linkages to the seal beam.Thelinkages moves a seal bar into sealing engagement across the width of the webto theseal bar unit constructed with a support beam and a seal bar connected to thebeam. Theseal bar unit is mounted as a substantially stationary unit during sealing andis supportedby a plurality of air cylinder units for positioning from standby to anoperating position.Each air cylinder unit includes an adjustable stop unit secured to the back ofthe cylinderunit and connected to the cylinder piston for adjusting the movement of thepiston andthereby the operative sealing position of the stationary seal bar unit. Someair cylinderunits are connected to the seal bar unit for positively moving the same andothersadditionally includes pad abutting the seal bar units fox supporting the samebetween thetwo positions.