Heat sealing apparatus

A sealing head for sealing containers of perishables on a pallet between a plastic sheet and a plastic bag, comprising:

• two triangular plates;
• a first heat roller;
• a first roller axle extending between the two triangular plates and coupled to the first heat roller;
• a second heat roller;
• a second roller axle extending between the two triangular plates and coupled to a second heat roller;
• and
• a plurality of heating elements positioned within cavities in the first heat roller and the second heat roller and configured to heat the first heat roller and the second heat roller,
• wherein the first heat roller and second heat roller are configured to be heated and roll around an overlap area defined by margins of a plastic bag positioned over containers of perishables on a pallet and margins of a plastic sheet positioned between the containers and the pallet in order to weld the plastic bag to the plastic sheet.

A heat sealing system for sealing containers of perishables on a pallet between a plastic sheet and a plastic bag, wherein the plastic bag is positioned over the containers, wherein the plastic sheet is positioned between the containers and the pallet with margins of the plastic sheet folded to overlap margins of the plastic bag in an overlap area, the system comprising:

• a turntable configured to support and rotate the pallet around a first axis of rotation;
• a heat sealer apparatus comprising:
• an arm;
• an arm actuator system coupled to a first end of the arm and configured to rotate the arm around a second axis of rotation parallel to the first axis of rotation;
• and
• a sealing head comprising at least one heat roller, wherein the sealing head is coupled to a second end of the arm opposite the first end of the arm, wherein the at least one heat roller comprises internal heating elements configured to heat an outer surface of the heat roller,
• wherein the arm actuator is configured to continuously position the arm so that a distance between the heat roller of the sealing head and the first axis of rotation is adjusted so that the heat roller contacts the overlap area as the pallet is rotated a complete 360 degree rotation on the turntable in order to form a continuous heat seal band around an entire perimeter of the overlap area in order to define a sealed enclosure between the plastic bag and the plastic sheet,
• wherein the sealing head comprises:
• two triangular plates;
• a first roller axle extending between the two triangular plates and coupled to a first heat roller of the at least one heat roller;
• a second roller axle extending between the two triangular plates and coupled to a second heat roller of the at least one heat roller;
• and
• a coupling axle extending between the two triangular plates and rotatably coupled to the arm.