Abstract: An apparatus for application of zippers to film material 10 comprises an applicator bar 22 for presenting pre-cut lengths of zipper 26 to the film and a heated sealing bar 34 for sealing the pre-cut lengths to the film. The applicator bar, the sealing bar, feed rollers 30a, 30b and a zipper cutter 32 are mounted for movement with the film on a linear motor 14. A pneumatic cylinder 18 raised the application bar towards the film 10. The applicator bar moves in direction C to apply the zipper to the film 10 moving in direction A, then moves with the sealing bar and the film in direction B, away from the film in direction C?, back to its starting position in direction B?, then towards the film again in direction C. A further length of zipper may be fed to the applicator bar at any time after the bar has moved away from the film in direction C? and therefore during an end portion of the forward stroke of the motor, or during its return stroke.

Abstract: The bags are produced on a form-fill-seal machine operating horizontally or vertically. Zipper strips (16) are initially attached to a continuous web (12) which is subsequently formed into a continuous run of bags having end seals (20) and a back seal (18). The continuous run is separated into individual bags and the zipper strips finally attached to the bag walls by application of heat and/or pressure by a belt sealer (26) operating in a direction perpendicular to that of movement of the continuous web.