US 5,332,381 AGranted

Two piece crown liner punch

AssigneeZapata Technologies, Inc.

InventorMichael Shapcott

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Abstract

An apparatus for forming liners of thermoplastic material within closure shells contains a movable die having an inner punch member and an annular outer mold member both of which are movable up and down in relatively slidable relation with each other and arranged so that the inner punch takes its lowermost position after the outer mold member has taken its lowermost position. In one embodiment of the present invention, the lower end surface of the outer mold member is beveled and defines a plurality of radial grooves. The lower end wall of the outer mold member is moved downwardly until it is opposite the horizontal wall of the closure shell. As the inner punch moves into its lowermost position, thermoplastic material is forced through the radial grooves so that a thick annular pad portion of the seal liner is formed beneath the lower end wall of the outer mold member.

Claims16

Dependent claims

A molding device for forming a liner on an inside surface of an inverted closure shell having a liner material thereon, comprising:

a support surface for supporting an inverted closure shell having a base and a sidewall;
a main body having a first lower end portion;
a center punch having a lower surface fixed to the first lower end portion with the lower surface of the center punch adapted to be positioned opposite to a central portion of the inside surface of a closure shell supported on the supporting surface;
an elevator mechanism for moving the main body with respect to the supporting surface;
and
an annular bushing positioned externally of the center punch, said annular bushing being movable with respect to the main body and having a second lower end portion defining a mold cavity and a plurality of flow passages, wherein said second lower end portion of said annular bushing includes an inner diameter for contacting the base of the closure shell and an outer diameter for contacting the sidewall of the closure shell and preventing the escape of liner material from the mold cavity, said flow passages extending through the inner diameter of the second lower end portion, but not extending to the outer diameter of the second lower end portion.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/020,962Filed 22 Feb 1993
Granted: 26 Jul 1994
Term ends: Not estimatedThe source records don’t support an estimate.

Classification10 codes

B29C 43/18
Of articles of definite length, i.e. discrete articles: incorporating preformed parts or layers, e.g. compression moulding around inserts or for…
B29C 43/361
Moulds for making articles of definite length, i.e. discrete articles: with pressing members independently movable of the parts for opening or…
B29C 70/80
Moulding material on one side only of the preformed part: moulding sealing material into closure members
B29C 33/02
Moulds or cores; Details thereof or accessories therefor: with incorporated heating or cooling means