초록 ▼

A perforating apparatus for use in the formation of shrink film packages is disclosed. The apparatus comprises a bottom seal tool with a plurality of peninsula regions forming a plurality of window areas. Each pair of window areas has a knife receiving area to receive a knife retaining block. The re

A perforating apparatus for use in the formation of shrink film packages is disclosed. The apparatus comprises a bottom seal tool with a plurality of peninsula regions forming a plurality of window areas. Each pair of window areas has a knife receiving area to receive a knife retaining block. The retaining block contains a perforation knife that extends beyond the surface of the sealing tool a sufficient distance to perforate the packages. At least one screw member extends through the peninsula, contacting the retaining block and securing the retaining block within the retaining channel. A change plate, having slots dimensioned and located to receive the knife blades is placed over the sealing tool surface. The packages are placed on the change plate and sealed by contacting the package with the upper platen. The upper platen is provided with a nonconductive material positioned to receive the knife blade. The resulting package has a perforation through the paperboard extending from one edge to the plastic window. This perforation enables the package to be easily opened.

대표청구항 ▼

[ What is claimed is:] [12.]12. A shrink film package, said package having a plastic window region, an intermittent heat seal line, and a perforation line, said perforation line extending substantially from a peripheral edge of said package to a window region, said line of perforations in said packa

[ What is claimed is:] [12.]12. A shrink film package, said package having a plastic window region, an intermittent heat seal line, and a perforation line, said perforation line extending substantially from a peripheral edge of said package to a window region, said line of perforations in said package being at about a right angle to said intermittent seal line and crossing said intermittent seal line in an unsealed area. [14.]14. The method of forming perforated tear openings in paperboard packages comprising the steps of:sealing a heat formable, heat sealable plastic sheet to a paper blank, said paper blank having peripheral edges and a window within said peripheral edges, said window being covered by said plastic sheet, said plastic sheet having peripheral dimensions that are substantially greater than the peripheral dimensions of said window, said plastic sheet being sealed to said paper blank in the region of said plastic sheet between the peripheral edges of said window and the peripheral edges of said paper blank and having at least one seal line that extends parallel to at least one of said peripheral edge of said window or said paper blank; applying heat to said plastic sheet and forming an article receiving pocket in said plastic sheet, said article receiving pocket extending through said window; inserting an article into said article receiving pocket; applying pressure to said paper blank with a perforation knife and forming perforations through said paper blank and said plastic sheet, said perforations extending substantially from a peripheral edge of said paper blank, across said at least one seal line to a peripheral edge of said window, whereby said perforations form a tear mechanism for tearing said paperboard and said plastic sheet and providing access to said article in said window.