Patents by Inventor Edwin P. Thomas

Edwin P. Thomas 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).

  • Circuit interlock arrangement
    Patent number: 4417778
    Abstract: An interlock arrangement utilizes a modification of printing circuit boards (11 and 41) and spring loaded locking levers (23 and 24). One printed circuit board (11) includes notches or detents (25 and 26) in which the locking levers rest to prevent the removal of the board after being inserted into its connectors (13-15). In order to remove the board, another printed circuit board (41) is utilized which has tapered portions (42 and 43) that displace the locking pins from the detents in the process of being inserted into auxiliary connectors (44 and 46). Thus, the first board may be removed while the second board provides a predetermined circuitry status via the interconnection of the two sets of connectors.
    Type: Grant
    Filed: October 23, 1981
    Date of Patent: November 29, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Henry J. Halvorsen, Albert V. Marchetto, Edwin P. Thomas