Patents Assigned to Soag Machinery Limited
  • Patent number: 3951199
    Abstract: A method of low pressure die casting in which molten metal in a furnace is forced up a riser tube into the die by gas pressure applied to the surface of the molten metal in the furnace by a pressure circuit, wherein as the level of the metal in the furnace falls after each successive die filling operation, the resultant increase in the time taken to exhaust the furnace pressure is utilised to produce compensatory incremental changes in the pressure applied in the circuit. The die casting apparatus for carrying out the method includes a remotely controlled pressure control valve which is controlled by a pressure adjusting means operable during the exhausting period of the furnace to apply the incremental changes in pressure to said valve. The apparatus may employ a single or a two-stage pressurisation.
    Type: Grant
    Filed: July 26, 1974
    Date of Patent: April 20, 1976
    Assignee: Soag Machinery Limited
    Inventor: Joseph Augustine Terence Pereira