Abstract: An apparatus and method for forming a hinged or clamshell type carton from a paperboard blank includes a feed conveyor for transferring the blank to a forming die. A hinge erecting conveyor is provided in the feed conveyor guide path to erect the hinge. A pair of pusher fingers form a shuttle conveyor in the guide path cooperating to transfer the partially erected blank to the die. Side channel guides arranged along the conveyor guide path maintain the partially erected paperboard blank in alignment with the erecting conveyor. Side channel guide extensions converge to maintain contacting engagement with the blank as selected carton panels converge during hinge formation and to support the blank in contacting registration on the face of the die and in the forming head path. A hinge gathering guide with hold down rails positioned above the erecting conveyor accurately locates and positions the carton blank and hinge.

Abstract: An apparatus and method for forming flat cut carton blanks into erected cartons with debowed carton side panels is disclosed. The apparatus includes a forming head receiving and directing a carton blank through forming guides. Pinching wheels rotatably secured adjacent the forming guides include a pinching notch with a leading edge projecting inwardly into the forming head path. The pinching notch engages the descending carton bottom and side panels to capture and pinch the fold lines and overbreak the side panels at the fold lines between the carton side and bottom panels. An inclined surface with a sharp creasing edge abutting the inside of the fold line assists the pinching notch in creasing the fold lines. An extension edge formed adjacent a trailing edge of the pinching notch completes the overbreaking action. A release edge formed adjacent the leading edge gently releases the carton side panels from the overbreaking position upon counter rotation of the wheel.