Patent ID: 6264459
Filing Date: 2001-07-24
Classification: B29C,Y10S

Abstract:
An injection moulding unit, comprising:at least two injection moulds for manufacturing successive disc-shaped objects, wherein the injection moulds each comprise:at least two mould parts which are mutually displaceable between a closed position in which the at least two mould parts bound a mould cavity and an opened position in which the disc-shaped object is removable, wherein the mould cavity is connected to a pressure line for carrying heated plasticized plastic under pressure into the mould cavity; andpunching means for punching a central hole through the disc-shaped object, wherein the punching means includes a cylindrical part forming a portion of one of the at least two mould parts and having a leading peripheral edge with a form configured to cooperate with the central hole through the disc-shaped object;wherein the cylindrical part is axially movable toward and away from the other of the at least two mould parts;wherein the pressure line for each of the injection moulds is a branch of a feed line and together therewith form part of a collective multiple hot runner, wherein an inlet zone of the feed line is configured to couple to an outfeed of a plastic-plasticizing and pressing device;wherein an outlet zone of the feed line is configured to couple to an infeed of an injection bush, wherein the injection bush includes an outfeed which debouches into the mould cavity;wherein the hot runner is coupled by spring means to a connecting piece of thermally conductive material, wherein the connecting piece is fixedly connected to the injection bush; andwherein the connecting piece includes tempering means for holding temperature of the connecting piece within predetermined limits.