Apparatus for sealing the heads of containers

Apparatus for sealing the heads of containers with heat shrinkable film comprising:

• means defining a sealing location;
• means for positioning containers to be sealed at their sealing location:
• means for intermittently feeding a continuous film of heat shrinkable material past said sealing location above a container located thereat;
• cutter means disposed at said sealing location above a container positioned thereat and including a vertically movable angular punch, said punch being sized and configured to cut from said heat shrinkable film individual portions thereof each forming a sealing sheet having a shape generally similar to the shape in plan view of said container head to be sealed but being larger in size than said container head so that when placed over a container head said sealing sheets will include an overhang portion extending beyond the periphery of said container head which will hang over along a portion of the side of said container;
• means for clamping said heat shrinkable film along portions thereof surrounding said portion forming said sealing sheet, said clamped portions being, prior to cutting of said sealing sheets, contiguous with said portion of said heat shrinkable film which form said sealing sheets, said clamping means including a vertically movable upper member and a stationary lower member located to have said film passed therebetween by said feeding means and to clamp said film therebetween during cutting of said sealing sheets, said upper and lower members of said clamping means being arranged to extend about said vertically movable annular punch in close proximity thereto thereby to act as a die member for said punch when said punch is actuated to cut said sealing sheets from said film;
• holding means positioned over the head of said containers placed at said sealing location and movable downwardly into engagement with said container heads to press said sealing sheets against said head after said sealing sheets have been cut from said film;
• means operatively associated with said holding means to fold said sealing sheets along the periphery of said container head to urge said overhand portions of said sealing sheets to extend downwardly along a portion of the sides of said containers;
• means for applying hot air against said molded overhang portions of said sealing sheets to heat seal said sheets upon said container heads;
• and
• cooling means physically joined with said clamping means and extending therewith in proximity to the portions of said clamping means which engage said heat shrinkable film portions during cutting-out of said sealing portions therefrom, said cooling means removing from said clamping means heat energy, particularly heat energy received from said hot air applying means, in order to maintain the temperature of said clamping means at a level sufficiently low to avoid deleterious shrinkage of said portions of said film clamped in said clamping means.