Patents by Inventor Hans Peter Leiste

Hans Peter Leiste 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).

  • Injection molding apparatus
    Patent number: 3945535
    Abstract: Apparatus for feeding to a mold a plasticized synthetic material containing a foaming agent, the apparatus using a heated extruder and its associated transfer cylinder which emits the material in a thin stream by means of a nozzle.
    Type: Grant
    Filed: August 5, 1974
    Date of Patent: March 23, 1976
    Assignee: Schloemann-Siemag Aktiengesellschaft
    Inventors: Hans Peter Leiste, Helmut Eckardt
  • Injection molding apparatus
    Patent number: 3937447
    Abstract: The invention is concerned with an injection molding apparatus in which thermoplastic material mixed with an expanding agent is kept in a plastic state below the reaction temperature of the agent and is passed generally continuously through an inter-connecting passage to a transfer cylinder; by flowing through the passage, the mass is heated above the reaction temperature and the built-up pressure prevents foaming of the thermoplastic until it is injected into a mold.
    Type: Grant
    Filed: September 7, 1973
    Date of Patent: February 10, 1976
    Assignee: Siemag Siegener Maschinenbau GmbH
    Inventors: Dieter Alwes, Helmut Eckardt, Hans Peter Leiste, Robert Albert Melcher