Patents by Inventor Frederik Hendrik Gerritsen

Frederik Hendrik Gerritsen 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).

  • Method of and device for testing hermetically enclosed reed contacts
    Patent number: 4028615
    Abstract: Method of and apparatus for testing magnetostrictive reed contacts for poorly conductive surface contamination. The reed contact is closed in a magnetic field generated by a direct current. An alternating current is conducted through the closed reed contact, the frequency sweeping through the torsional resonant frequency of the contact reeds. The tested contact surface of the contact reeds is thus maximized. The voltage generated across the reed contact by the alternating current is then measured.
    Type: Grant
    Filed: October 16, 1975
    Date of Patent: June 7, 1977
    Assignee: U.S. Philips Corporation
    Inventors: Friedrich Ludwig Jansen, Frederik Hendrik Gerritsen, Johan Hendrik Adolph Glashorster