Patents by Inventor Lillian Hristov Ivanchev

Lillian Hristov Ivanchev has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7368690
    Abstract: Apparatus for producing a semi-solid metal alloy from a molten charge includes vertically aligned treatment zones which are provided by vertically aligned passages defined by a plurality of spirally wound flow pipes which are interspersed between spirally wound induction coils. A container is mounted on a charging arrangement which displaces a first charge upwardly into the first treatment zone. Successive charges are introduced in a similar fashion thereby urging the previously introduced charge upwardly along the train of zones and until the leading charge is ejected from the top of the apparatus. The charge in each zone is subjected to controlled cooling and an induced electromagnetic field. The strength of the field and the rate of cooling are controlled to impede dendritic crystallisation and to promote globular primary crystal formation.
    Type: Grant
    Filed: May 14, 2007
    Date of Patent: May 6, 2008
    Assignee: CSIR
    Inventors: Retief Bruwer, Jeremias Daniel Wilkins, Lillian Hristov Ivanchev, Pierre Rossouw, Oliver Frank Rudolf August Damm
  • Patent number: 7225858
    Abstract: Apparatus for producing a semi-solid metal alloy from a molten charge includes vertically aligned treatment zones which are provided by vertically aligned passages defined by a plurality of spirally wound flow pipes which are interspersed between spirally wound induction coils. A container is mounted on a charging arrangement which displaces a first charge upwardly into the first treatment zone. Successive charges are introduced in a similar fashion thereby urging the previously introduced charge upwardly along the train of zones and until the leading charge is ejected from the top of the apparatus. The charge in each zone is subjected to controlled cooling and an induced electromagnetic field. The strength of the field and the rate of cooling are controlled to impede dendritic crystallisation and to promote globular primary crystal formation.
    Type: Grant
    Filed: February 3, 2004
    Date of Patent: June 5, 2007
    Assignee: CSIR
    Inventors: Retief Bruwer, Jeremias Daniel Wilkins, Lillian Hristov Ivanchev, Pierre Rossouw, Oliver Frank Rudolf August Damm
  • Patent number: 6063216
    Abstract: This invention relates to the working of a metallic strip. More particularly, the invention relates to a method of working a length of metallic strip by heat treating under tensile force, to a length of metallic strip and to an apparatus for use in working a length of metallic strip.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: May 16, 2000
    Assignee: Trico Products Corporation
    Inventors: Oliver F. R. A. Damm, Warwick John Green, Lillian Hristov Ivanchev, Walter Luigi Trevisan