Polystar Packaging, Incorporated

Robert W Fraser

Donald J Roth

William M Heyn

Kenneth E Cisek

Theodore J Fish

Donald G Sauer

Shaun T Broering

Kyle R Wilcoxen

Charles B Snoreck

Jack A Macpherson

Tim Larocque

Scott Binger

Tooling for forming an article which includes an injection molded peripheral frame defining an opening closed by a panel insert. The panel insert is struck from sheet material and together with an associated punch or carrier cooperates with a split mold to completely define the cavity for injection molding of the article. Inasmuch as the panel insert is heat bondable to the injection molded frame and forms a portion of the walls of the cavity, it is automatically bonded to the injection molded frame. The panel insert may be peelable from the frame and include a pull tab for effecting the same. The pull tab may be formed by the same punch which cuts out the panel insert, or the pull tab may be separately formed from sheet material adjacent an intended position of a panel insert and folded into overlying relation to the intended position of the panel insert and staked to the sheet material, after which the panel insert is cut from the sheet material by a punch. The pull tab is initially connected to the sheet material along an elongated fold line, after which not all of the pull tab connected to the sheet material is removed by the punch so as to define a centrally located pull tab which is aligned with the projecting part of the punch to effect a completely sealed mold cavity utilizing the panel insert with a previously formed and folded over pull tab staked thereto.

Method of molding a peripheral frame with a panel insert

A press-on closure 10 for a tubular container 12. The closure includes a molded plastic frame 14 having a ledge 28 on which an end panel 16 is seated and to which the end panel is peelably secured. The end panel has a free outer peripheral edge unbonded to the frame. The resultant closed container is subject to retorting with the result that heretofore the end panel could axially outwardly deform and possibly initiate internal peeling. To prevent this peeling, the frame is provided with a thin flexible integral flange 36 forming a continuation of the ledge on which the end panel is seated. The end panel is also peelably bonded to the flange and the flange deforms or deflects with the end panel. The frame has a press fit onto the container, which is preferably in the form of a metal can, which at the end thereof to be closed by the closure is provided with a radially outwardly directed curl 48. The curl terminates in a raw edge 54 and is so shaped that when it is seated within a groove in the underside of the frame, the raw edge is embedded in a skirt portion of the frame to permanently and sealingly lock the curl within the frame.

Press-on closure with peelable end panel

Method of making an injection molded frame having a panel insert

Tooling for forming an article which includes an injection molded peripheral frame defining an opening closed by a panel insert. The panel insert is struck from sheet material and together with an associated punch or carrier cooperated with a split mold to completely define the cavity for injection molding of the article. Inasmuch as the panel insert is heat bondable to the injection molded frame and forms a portion of the walls of the cavity, it is automatically bonded to the injection molded frame. The panel insert may be peelable from the frame and include a pull tab for effecting the same. The pull tab may be formed by the same punch which cuts out the panel insert, or the pull tab may be separately formed from sheet material adjacent an intended position of a panel insert and folded into overlying relation to the intended position of the panel insert and staked to the sheet material, after which the panel insert is cut from the sheet material by a punch. The pull tab is initially connected to the sheet material along an elongated fold line, after which not all of the pull tab connected to the sheet material is removed by the punch so as to define a centrally located pull tab which is aligned with the projecting part of the punch to effect a completely sealed mold cavity utilizing the panel insert with a previously formed and folded over pull tab staked thereto.

Apparatus for making an injection molded frame having a panel insert

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Stamford, CT, United States of America

Robert W Fraser