Patents by Inventor Shinn I. Chern

Shinn I. Chern 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).

  • Screw jack
    Patent number: 4609179
    Abstract: A screw jack which comprises a motor mounted in a housing which also houses a vertically mounted lifting screw assembly, a transmission unit for transmitting the output motion of the motor to the lifting screw assembly, and a limit switch means which is actuated by the screw assembly. The limit switch means includes an upper limit switch and a lower limit switch provided where the upward movement and the downward movement of the screw assembly are intended to be ended.
    Type: Grant
    Filed: May 23, 1985
    Date of Patent: September 2, 1986
    Inventors: Shinn I. Chern, Yih K. Jwo