Abstract: An apparatus for cleaning a seal bar of a bag-making machine comprises a frame positioned in operative association with the seal bar, and a carriage mounted on the frame for movement along the length thereof. An articulable cleaning member is mounted on the carriage for movement therewith along the frame, with the cleaning member including a cleaning head engageable with the seal bar by selective movement of the cleaning member relative to the carriage. By this arrangement, the cleaning head of the cleaning member can be positioned in engagement with the seal bar, and the carriage moved along the frame, whereby the cleaning head cleans/scraps the seal bar to remove built-up residue therefrom, thereby enhancing sealing performance.

Abstract: A method of boxing bag stacks supported on U-shaped wickets having the wicket cross-member on one side of the bag stack, including supporting a bag stack by grasping both the cross-member and the bag stack other end from the other side of the bag stack, moving the supported bag stack into a container, and releasing the bag stack in the container. An axially extending carrier includes a grasper on one axial end and is selectively extendable in a generally radial direction for selective engagement with the wicket cross-member from the other side of the bag stack. A grasping mechanism on the other axial end of the carrier extends in the generally radial direction to selectively grasp the bag stack other end.

Abstract: In an apparatus for making plastic bags or the like from a continuous film of material comprising a sealing drum having at least one seal bar for imparting transverse seals to the film at regularly spaced intervals and a perforator having a rotatable perforator blade for imparting transverse perforations to the film at regularly spaced intervals, the film comprising print marks appearing thereon at regularly spaced intervals, an apparatus and method are disclosed for tracking the positions of each print mark and each perforation and comparing the difference between these positions to a desired difference and thereafter adjusting the angular position of the perforator blade until the difference between the positions of each print mark and each perforation is equal to the desired difference to thereby maintain a desired spacing between each print mark and each perforation.

Abstract: In an apparatus for making plastic bags or the like from a continuous film of material comprising a sealing drum having at least one seal bar for imparting transverse seals to the film at regularly spaced intervals and a perforator having a rotatable perforator blade for imparting transverse perforations to the film at regularly spaced intervals, an apparatus and method are disclosed for tracking the positions of each seal and each perforation and comparing the difference between these positions to a desired difference and thereafter adjusting the rate of rotation of the perforator blade until the difference between the positions of each seal and each perforation is equal to the desired difference to thereby maintain a desired spacing between each seal and each perforation.

Abstract: In an apparatus for rolling up web material which comprises a disk or turret rotatably mounted on a stationary frame and a plurality of mandrels rotatably mounted to the disk, each mandrel being indexable to each of a take-up position, a waiting position and a removal position through selective rotation of the disk, the improvement which comprises a source of compressed air connected to the frame adjacent the removal position, a separate vacuum tube apparatus connected to the frame adjacent the waiting position and being axially movable toward and away from the waiting mandrel, a vacuum pump connected to the vacuum tube apparatus for creating a vacuum in the vacuum tube apparatus, the mandrels each comprising a longitudinal bore extending from an open end thereof and a plurality of radial nozzles communicating with the longitudinal bore, wherein the vacuum tube apparatus is selectively movable into contact with the open end of the waiting mandrel so that the vacuum is communicated through the nozzles to there

Abstract: In an apparatus for making plastic bags or the like from a continuous film of material comprising a sealing drum having at least one seal bar for imparting transverse seals to the film at regularly spaced intervals and a perforator having a rotatable perforator blade for imparting transverse perforations to the film at regularly spaced intervals, the film comprising print marks appearing thereon at regularly spaced intervals, an apparatus and method are disclosed for tracking the positions of each print mark and each perforation and comparing the difference between these positions to a desired difference and thereafter adjusting the angular position of the perforator blade until the difference between the positions of each print mark and each perforation is equal to the desired difference to thereby maintain a desired spacing between each print mark and each perforation.

Abstract: A method and apparatus for producing thermoplastic bags from an elongate web. Apparatus for feeding the web includes devices for producing mounting holes and perforations along a circular path surrounding the holes. The web is severed and sealed to produce sheets containing a mounting hole encircled by the perforations. A selected number of successive sheets are impaled on a post projecting through the holes. A stack having a selected number of sheets is accumulated on a post fixed to a support supporting a medial zone of the sheets which are combined by a heated punch penetrating the sheets in the area enclosed by the perforations.

Abstract: Disclosed is an apparatus for slitting a continuous strip of thermoplastic web by a knife heated to a temperature below the melting or fusing temperature of the web. By heating the knife the cutting force is substantially reduced.