Crown Cork & Seal Technologies Corporation

Carnaudmetalbox Plc

Donald E Griffiths

Christopher Paul Ramsey

Philippe Odet

Roderick M De'ath

Peter Frank Woodward

Michael Barrie Simpson

Robert McDonald Gillies

A snap-on or screw type, tamper evident closure having first and second relatively moveable plastic parts ( ) which move from an initial position to a new limiting position when the closure is first opened, the new limiting position being visually distinguishable from the initial position to provide the tamper evidence. The two plastics parts are formed in mutually intimate association but have inter-engaging complimentary formations ( ) which become irreversibly disengaged on first opening of the closure.

Tamper evident closures

A method of forming a component having a metallic shell (12) and a plastics insert (34). The component is formed by placing the shell (12) inside the mould cavity of a mould assembly (10) which forms part of an injection moulding machine. Prior to injection of plastics material, part of the external surface of the shell (12) is spaced from the opposed surface of the mould cavity. The open end of the shell abuts the adjacent mould cavity and wall so as to form a seal. This end wall is frusto-conical in shape so that, during injection of plastics material, as the shell (12) is reformed by polymer pressure into complete engagement with the surface of the mould cavity, longitudinal contraction of the shell in response to this direct lateral strain is compensated for by the frusto-conical shape so that the seal is maintained.

Method of injection moulding a polymeric material insert into a metal

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Paignton, United Kingdom

Donald E Griffiths