Patents Assigned to Georg Fischer DISA AG
  • Patent number: 6460604
    Abstract: An apparatus for uphill low pressure casting of molten metal in sand molds conveyed in synchronized manner with a casting station located at the conveyor, a gas pressure holding furnace containing the molten metal and located at the casting station with a rising casting tube connectable to the sand molds has a device for refilling the holding furnace with molten metal. To permit a rapid casting cycle and high casting capacities, the refilling device has at least one pressure-tight melt container and a filling tube located in the holding furnace with a seal positioned outside the same. The melt container is couplable in pressure-tight manner by means of its outlet to the holding furnace filling tube. The holding furnace is connected to the melt container by means of a pneumatic pressure compensating line.
    Type: Grant
    Filed: October 4, 1999
    Date of Patent: October 8, 2002
    Assignee: Georg Fischer DISA AG
    Inventors: Norbert Damm, Herbert Zulauf
  • Patent number: 6460603
    Abstract: An apparatus for uphill low pressure casting of metals in split sand moulds and having a sprue in one of the two moulds, to which can be connected the casting tube of a melt container and which is connected to the lowest area of the mould cavity, and having a sealing plug integrated into the mould and which after the filling of the mould cavity can be brought into the closed position by means of an external drive engaging in the mould, including a seal which does impairing casting quality and moulding sand preparation. Between the sprue and the mould cavity is provided a casting channel connecting the sprue and the mould cavity. The sealing plug is constructed as a sand mould body and in a shaped-in guide of the mould is displaceable between an open position and a closed position, and seals a casting channel and a metallostatic pressure of the molten metal in the mould acts against the guide on the sealing plug.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: October 8, 2002
    Assignee: Georg Fischer Disa AG
    Inventors: Norbert Damm, Herbert Zulauf
  • Patent number: 6321825
    Abstract: In the case of uphill low pressure casting of metals, particularly light metal, a casting mold is connected by its gate, via a riser to a melting container and the melt contained therein is displaced under pressure through the riser into the mold. For increasing the casting capacity while maintaining a high quality of the casting, most of the melt volume necessary for filling the mold is displaced into the latter at the maximum casting speed, then the melting column in the riser is sheared and a residual volume remaining between the shearing point and the gate is displaced into the mold with a negative speed gradient. An apparatus for performing the above process is includes a tubular portion provided between the riser and the gate, the tubular portion forming a residual volume, an opening being formed between the riser and the tubular portion.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: November 27, 2001
    Assignee: Georg Fischer DISA AG
    Inventors: Norbert Damm, Herbert Zulauf
  • Patent number: 6283831
    Abstract: For desanding castings cast in moulding sand by means of at least one fluid pressure pulse acting on the sand mould, the fluid is bundled into at least one cutting jet and the latter is made to act directly on the sand mould.
    Type: Grant
    Filed: October 6, 1999
    Date of Patent: September 4, 2001
    Assignee: Georg Fischer DISA AG
    Inventors: Kurt Fischer, Hans Leutwiler
  • Patent number: 5836369
    Abstract: Used foundry sand is divided into two falling streams and the grains of a first falling stream are accelerated and diverted into the second falling stream.
    Type: Grant
    Filed: October 2, 1996
    Date of Patent: November 17, 1998
    Assignee: Georg Fischer Disa AG
    Inventors: Christian Renner, Jovo Laskovic