Patents by Inventor Harold G. Lemmer

Harold G. Lemmer 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).

  • Colloidal graphite forging lubricant and method
    Patent number: 4050932
    Abstract: An improved colloidal graphite hot forming lubricant and hot forming process for high density ferrous powdered metal articles using this lubricant. Extremely fine powdered copper is included in an otherwise conventional colloidal graphite hot forming lubricant. High quality, including high density, ferrous metal articles are produced by coating a ferrous powdered metal preform with this lubricant, presintering the coated preform at a higher temperature of 2100.degree. - 2500.degree. F. for a short time by induction heating, allowing the presintered preform to cool to a desired hot forming temperature below 2000.degree. F., and then hot forming the preform in the usual manner. Lubricant-preform interaction at the higher temperature is precluded, making long presintering times and special presintering equipment necessary.
    Type: Grant
    Filed: August 5, 1976
    Date of Patent: September 27, 1977
    Assignee: General Motors Corporation
    Inventor: Harold G. Lemmer
  • Graphite and copper in hot forging liquid lubricant
    Patent number: 4013570
    Abstract: An improved colloidal graphite hot forming lubricant and hot forming process for high density ferrous powdered metal articles using this lubricant. Extremely fine powdered copper is included in an otherwise conventional colloidal graphite hot forming lubricant. High quality, including high density, ferrous metal articles are produced by coating a ferrous powdered metal preform with this lubricant, presintering the coated preform at a higher temperature of 2100.degree. - 2500.degree. F. for a short time by induction heating, allowing the presintered preform to cool to a desired hot forming temperature below 2000.degree. F., and then hot forming the preform in the usual manner. Lubricant-preform interaction at the higher temperature is precluded, making long presintering times and special presintering equipment necessary.
    Type: Grant
    Filed: April 7, 1975
    Date of Patent: March 22, 1977
    Assignee: General Motors Corporation
    Inventor: Harold G. Lemmer