Patents by Inventor William A. Shubin

William A. Shubin 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).

  • Patent number: 6715586
    Abstract: A method for upgrading an elevator control circuit having a phase 1, alternate and phase 2 input circuits, includes placing a first impedance of a switching device across a door motor armature of the elevator control circuit for enabling a selected door closure speed, and placing a second impedance of the switching device in series with a door motor field of the elevator control circuit for enabling a selected door operating torque. The method further provides a logic circuit enabling the impedances when an input signal is present at, at least one of, the phase 1 and the alternate input circuits; and disabling the impedances when an input signal is present at the phase 2 input circuit.
    Type: Grant
    Filed: April 22, 2002
    Date of Patent: April 6, 2004
    Inventor: William A. Shubin