Shrink oven

A shrink oven for heating and shrinking plastic film disposed about loads, said oven having an exit opening for exit of a first load, said oven characterized in having movable means to move a second load through an entry opening into said oven, synchronizing means for causing said movable means to move in a manner dependently with exit movement of said first load to displace heated oven air to fill the air space left behind said first load as it exits the oven, thereby to limit inward flow of cool air during exit of the load, means to stack an entering or exiting load closely adjacent to another load to limit flow of heated air at the outer end of said load as it enters or exits said oven, and means to maintain spacing of a load from adjacent loads while said load is resident in said oven to expose the end of said load to heat, there being first and second conveyors at the entrance and exit openings, respectively, of said oven, operable at the same speed for supplying a fresh load while a heated load is removed, and a further conveyor within said oven operable to remove a load from said first conveyor, position said load for exposure of its ends to heat and deliver the heated load to said second conveyor,

• said further conveyor driven dependently with, and at a faster speed than, said first and second conveyors, said conveyors adapted to stop in unison while a load is on said further conveyor in said oven and spaced from adjacent loads, whereby conservation of energy and improvement in the shrink cycle can be obtained.