Patents Assigned to Coraltech Limited
  • Patent number: 6726873
    Abstract: A mould tool comprises a primary cavity part (201), a core part (202), a secondary cavity assembly (203) and an actuation ring (204). The primary cavity part (201) is attached to the fixed platen of a moulding machine in use and incorporates an injection gate (211). The core part (202) is attached to the moving platen and has a fixed portion (2021) having outside its preform shaping surfaces (20211) four pivot points (224)—of which two are shown—for the secondary cavity petals (2030), of which there are four. Also the core part incorporates a movable portion (2022), comprised of a preform shaping end plate (20221), a carrier (20222) for the end plate, a pair of movement rods (20223) to which the carrier is attached and which are housed in bores (20224) in the core (202) via linear bearings (20225).
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: April 27, 2004
    Assignee: Coraltech Limited
    Inventor: Peter Reginald Clarke
  • Publication number: 20040018266
    Abstract: A metering device is disclosed for use in a plastics moulding machine having a mould cavity, relatively movable platens and a feeding passage for feeding a plastics melt into the mould cavity. The metering device comprises a heated block interposed between the feeding means and the mould cavity. A cylinder with a moving piston is formed in the block. A first passage in the block connects the cylinder to the feeding means and a second passage connects the cylinder to the mould cavity. Valves in the passages enable the cylinder to be filled by the feeding passage without the plastic melt entering the mould cavity and subsequently enable the desired dose of plastics melt, when ejected from the cylinder by the piston, to flow from the cylinder to the mould cavity without being returned to the feeding passage.
    Type: Application
    Filed: July 9, 2003
    Publication date: January 29, 2004
    Applicant: Coraltech Limited
    Inventor: Peter Reginald Clarke
  • Patent number: 6402725
    Abstract: A cup of plastics material incorporating foaming agents has thin wall portions, namely a base (101), a lower side wall (102) and an upper side wall (103). These portions have their wall thickness determined by mold part gap. The cup also has thick wall portions, namely the corner (104), the band (105) and the rim (106), in which foaming occurs after mold opening so that the wall thickness is increased beyond that provided by the mold.
    Type: Grant
    Filed: April 16, 1999
    Date of Patent: June 11, 2002
    Assignee: Coraltech Limited
    Inventor: Peter Reginald Clarke
  • Patent number: 6358446
    Abstract: A method of forming an article via injection of plastics material into a mould consisting in the steps of: providing a mould tool (11) defining in its closed state a mould cavity, the mould tool being adapted to be partially expandable from an injection volume (FIG. 2) for receiving a load of plastics material to a final, larger volume (FIG.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: March 19, 2002
    Assignee: Coraltech Limited
    Inventor: Peter Reginald Clarke
  • Patent number: 6287494
    Abstract: The cylinder head (8) of an injection molding machine has a transverse bore (20), in which is threadedly engaged a gas introduction device (21) connected to a gas bottle (22), having a pressure regulator (23). The device has a body (24) which carries a valve poppet (25) in a complementarily shaped bore (26) opening to the passage through the cylinder head. A spring (27) normally closes the poppet valve. A control valve (28), under control of the system (7) is provided upstream of the poppet valve. Gas is introduced into the injection chamber of the machine after suck back and before screw rotate for feeding plastics material to the injection chamber. On injection, the material is injected with the gas added to it.
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: September 11, 2001
    Assignee: Coraltech Limited
    Inventor: Peter Reginald Clarke
  • Patent number: 5985191
    Abstract: A cup of plastics material incorporating foaming agent has thin wall portions, namely a base 101, a lower side wall 102 and an upper side wall 103. These portions have their wall thickness determined by mould part gap. The cup also has thick wall portions, namely the corner 104, the band 105 and the rim 106, in which foaming occurs after mould opening so that the wall thickness is increased beyond that provided by the mould.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: November 16, 1999
    Assignee: Coraltech Limited
    Inventor: Peter Reginald Clarke