Patents by Inventor Ann E. Schoenjahn

Ann E. Schoenjahn 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).

  • Determination of carbon analysis in irons
    Patent number: 4008604
    Abstract: A new, accurate method for the determination of percent total carbon in a molten hypoeutectic or hypereutectic iron is disclosed. It has been found that percent total carbon content of a molten iron is related to a straight-line function of the difference in liquidus and eutectoid transformation (i.e., austenite to pearlite) temperatures of the iron. A standard liquidus - eutectoid transformation temperature difference (based on total carbon content) is generated. A molten iron sample is cooled through the eutectoid transformation temperature and the difference in the liquidus and eutectoid transformation temperatures is compared with the standard liquidus-eutectoid transformation temperature difference to determine the percent total carbon of the sample.
    Type: Grant
    Filed: April 7, 1976
    Date of Patent: February 22, 1977
    Assignee: Deere & Company
    Inventors: Maurice P. Roach, Ann E. Schoenjahn, Larry G. Carmack