Method of embodying a foil sheet in a thermoplastic object during the process of manufacturing said object

Claim 1

A method of incorporating a sheet of foil in an object made from a thermoplastic material by injection moulding techniques during the process of making said object, said method comprising inserting foil piece between the plunger and die of an open mould in an injection moulding machine prior to the closing of the mould and to the injection of a moulding compound into the mould via an injection nozzle in said die, said foil piece being cut to size being inserted singularly between the open mould halves, said foil piece having a hole therein, said foil piece being inserted laterally between said mould halves from one side thereof at the same time as the mould is opened to eject a moulded object therefrom from the other side thereof, holding said foil piece in a localized position between the plunger and die so as to substantially cover the free end of the plunger with the hole facing said free end and the injection nozzle in the die, the foil piece having at least one flap projecting outside the end surface of the plunger, closing the mould while transporting the foil piece into the mould between the plunger and die so that the foil piece is bent to shape as the flap is folded into the die and located along one side portion of the plunger, said die being formed with a convex protrusion at said injection nozzle facing a central recess formed in the plunger such that when the mould is closed the convex protrusion on the die comes into contact with the edge of the foil surrounding the hole to displace the foil edge into the recess in the plunger while pressing the foil into contact with the plunger at the edge of said recess, injecting moulding compound into the mould through the injection nozzle in the die and through the hole in the foil piece, the foil piece being moved into abutment with the die by the influence of the moulding compound acting on said foil piece as a result of contact of the foil piece around the hole with the convex protrusion of the die around the injection nozzle, the flow of moulding compound from the nozzle being so deflected by the recess in the plunger, that said moulding compound is guided outwardly towards the foil piece away from the hole edge, so that the foil piece is caused to adopt a position on the outside of the moulding compound so as to adhere to said compound as a result of the heat and pressure exerted therefrom while cooling a mould portion abutting the foil piece so as to avoid damage to said foil piece.

Claim 2

A method of incorporating a sheet of foil in an object made from a thermoplastic material by injection moulding techniques during the process of making said object, said method comprising inserting foil piece between the plunger and die of an open mould in an injection moulding machine prior to the closing of the mould and to the injection of a moulding compound into the mould via an injection nozzle in said die, said foil piece being cut to size being inserted singularly between the open mould halves, said foil piece having a hole therein, said foil piece being inserted laterally between said mould halves from one side thereof at the same time as the mould is opened to eject a moulded object therefrom from the other side thereof, holding said foil piece in a localized position between the plunger and die so as to substantially cover the free end of the plunger with the hole facing said free end and the injection nozzle in the die, the foil piece having at least one flap projecting outside the end surface of the plunger, closing the mould while transporting the foil piece into the mould between the plunger and die so that the foil piece is bent to shape as the flap is folded into the die and located along one side portion of the plunger, said die being formed with a convex protrusion at said injection nozzle facing a central recess formed in the plunger such that when the mould is closed the convex protrusion on the die comes into contact with the edge of the foil surrounding the hole to displace the foil edge into the recess in the plunger while pressing the foil into contact with the plunger at the edge of said recess, injecting moulding compound into the mould through the injection nozzle in the die and through the hole in the foil piece, the foil piece being moved into abutment with the die by the influence of the moulding compound acting on said foil piece as a result of contact of the foil piece around the hole with the convex protrusion of the die around the injection nozzle, the flow of moulding compound from the nozzle being so deflected by the recess in the plunger, that said moulding compound is guided outwardly towards the foil piece away from the hole edge, so that the foil piece is caused to adopt a position on the outside of the moulding compound so as to adhere to said compound as a result of the heat and pressure exerted therefrom while cooling a mould portion abutting the foil piece so as to avoid damage to said foil piece.