Abstract: A method and apparatus for forming bags, such as from a continuous sheet of thermoplastic film fed forwardly and wrapped over a forming tube with the contents being filled into the bag through the tube and the end of the film formed into a bag tube being cross-sealed. The lower end of the filling tube is constructed so as to elastically deform and spread as sealing members move in laterally and thereby spread and flatten the tube to insure the making of a seal which is devoid to wrinkles and leakage possibilities.

Abstract: A zipper guide and spreader device for form, fill and seal apparatus comprises a package material guiding and spreading mechanism wherein a pair of articulated members have zipper guideways. The members are hingedly connected together and one of the members is hingedly connected to a fixed support. An actuator operates the articulated members from a biased relaxed position into an articulated material-spreading position wherein the material is spread for eliminating wrinkles before edge sealing across the material below the discharge end of the forming and filling tube.

Abstract: An ultrasonic servo controller circuit is disclosed which is used to detect the edge of a web and adjust the web position as it is dispensed from a pay-off roll to packaging machinery. The circuit is utilized to control a motor which operates a linear actuator to "de-oscillate" the web thereby providing the packaging machinery with a steady, non-oscillating sheet of material.

Abstract: A tray for foodstuffs or the like having a continuous edge rim and a flexible cover placed over the top of the tray and sealed to the rim with an elongate continuous interlockable separate rib and groove profile on strips sealed to the surface of the cover wherein upstanding pull flanges above the rib and groove profiles may be pulled apart and the cover severed between the profiles for access to the contents so that the cover may be opened and closed.

Abstract: A flexible continuous reclosable plastic zipper having one strip with a groove and another strip with a rib for interlocking insertion therein, a hot melt plastic peel seal in the base of the groove with the rib bonded to the peel seal material to initially join the rib and groove and with the rib and groove breaking apart away from the bonding material at the first opening and thereafter releasably interlocking in a normal manner with the peel seal material remaining within the groove. The groove is made sufficiently deep so that with initial interlocking, the rib must penetrate to the base of the groove deeper than normal operation to lock to the peel seal. When broken from the peel seal, the rib inserts sufficiently for the jaws of the groove to snap over the rib and then locks without interference from the peel seal which is relatively rigid and nonadhesive after the rib is first broken away.

Abstract: A method and mechanism for continuous wrapping of objects in a product package having a reclosable zipper thereon, providing a continuous sheet of thermoplastic film with a reclosable rib and groove fastener profile extending therealong parallel to the formation axis of the film with the profiles interlocked to form a flattened closure, guidingly wrapping the sheet around the object, simultaneously guiding the interlocked fastener to an upright position relative to the object, and flattening the upright interlocked profiles against an outer surface of a wall of the object and thereafter cross-sealing the film at the ends of the object locking the flattened profile to the package end.

Abstract: A tray for foodstuffs or the like having a continuous edge rim and a flexible cover placed over the top of the tray and sealed to the rim with an elongate continuous interlockable separate rib and groove profile on strips sealed to the surface of the cover wherein upstanding pull flanges above the rib and groove profiles may be pulled apart and the cover severed between the profiles for access to the contents so that the cover may be opened and closed.

Abstract: A method and apparatus for forming bags such as in a form, fill and seal machine wherein the bags are formed by drawing film downwardly over a filling tube and cross-sealing the bag tube and applying a lateral stretching force to the bag tube at the location of cross-sealing preventing wrinkles at the location of the seam formed by the cross-sealing with the stretching force applied at the extreme lateral edge of the film preferably by opposed cam surfaces at each of the bag edge which contact each other at a point just outside of the bag edges and progressively walk into the edge of the bag with the point of contact shifting in an outward direction while it progresses inwardly on the bag to apply a stretching force to the film of the bag for smoothing the entire width.

Abstract: A method and mechanism for advancing a continuous length of bag making plastic film having a reclosable fastener strip extending therealong with a filling tube over which the film is formed, means for sealing the edges of the film over the filling tube, opposed pairs of advancing belts for pressing the film against the tube and driving it incrementally downwardly, means for guiding the fastener between the belts of one of the pairs and means for driving the belts incrementally to move the film downwardly as it is filled and cross-sealed.