Stretch bag wrapping machine

Claim 1

A stretch-bag mechanism for drawing a resilient plastic bag in a stretched condition down over a load and for releasing the bag so that it provides a tight, tensioned wrapping for the load, said mechanism including: a frame having an inner dimension of a shape and size to fit over the load in a circumscribing relationship therewith; a hoist assembly coupled to the frame for raising the frame to an upper position and to lower the frame to a lower position down over the load; a plurality of upright horn members attached to the frame for receiving the sides of the resilient plastic bag as it is placed in an inverted position over the frame, at least one of said horn members being moveable inwardly with respect to the frame to permit the horn members to receive the bag in a relaxed condition, and being movable outwardly for causing the horn members to exert a lateral stretching force on the bag; first drive means coupled to said one of said horn members for moving the same inwardly and outwardly; spring-biased roller means mounted on respective ones of said horn members for engaging the outer surface of the bag as the sides of the bag are drawn down over the horn members and between the horn members and the corresponding roller means to cause the roller means to press the sides of the bag against the horn members; and second drive means mechanically coupled to the roller means to cause the roller means to turn and gather the bag between the horns and the roller means into an accordion-like configuration about the frame while the bag is in a relaxed condition, so that the bag may be subsequently stretched outwardly by movement of said one of said horn members and peeled over the load as the frame is lowered by the hoist assembly.