Patents Examined by H. Li
  • Power stage servo valve for a seismic vibrator
    Patent number: 4442755
    Abstract: A power stage servo valve for a seismic vibrator includes a stationary orifice plate defining a plurality of valve ports having a first shape. A rotary orifice plate, abutting the stationary orifice plate, defines a like plurality of valve ports that have a shape different from the valve ports in the stationary orifice plate. The configuration and shape of the rotary valve ports is such that the valve opens more quickly than it shuts off when the plate is rotating continuously in one direction at a desired angular velocity.
    Type: Grant
    Filed: January 25, 1982
    Date of Patent: April 17, 1984
    Assignee: Litton Resources Systems, Inc.
    Inventor: Marek L. Rozycki