Packaging film feeding apparatus and method

Abstract

A form, fill and seal packaging machine includes a tube former for forming a film having spaced apart registration marks thereon into a tube around a hollow mandrel. A pair of endless belt devices driven by stepping motors, located at the sides of the hollow mandrel advances the film through the machine. A stripping and sealing apparatus is located beneath the mandrel, for stripping product from the area of the film tube to be sealed, and sealing and cutting a filled package from the tube. A photoelectric cell located upstream of the tube former senses the passing of each registration mark as the film is fed. The photoelectric cell is operatively associated with the belt drive and the actuator for the stripper and the sealer through an index controller. The index controller deactivates the stepping motors. A master controller activates the stripper/sealer actuator at a predetermined point in each packaging cycle. A method of making form, fill and seal packages of constant length includes the steps of intermittent feeding by increments a full length of film having a registration mark at an intermediate point, sensing said registration mark during the time the film is being fed, counting predetermined feed increments past the registration mark during continued film feeding, and sealing the package at a location identified by reaching the predetermined number of feed increments.