Patents by Inventor Raud Wilke

Raud Wilke 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).

  • Hall effect valve spool position sensor
    Patent number: 6152172
    Abstract: A hydraulic control valve has a spool slidably received in a bore of the valve body. The spool can be moved in opposite directions to control flow fluid to and from a pair of workports. A sensor assembly has a coupling attached to the spool and holds a permanent magnet. A Hall effect sensor produces an electrical signal indicating the position of the permanent magnet and thus the spool. A double acting spring assembly biases the coupling and spool with respect to the housing of the sensor when the spool moves in one direction, and biases the coupling and spool with respect to the valve body when the spool moves in the other direction.
    Type: Grant
    Filed: July 28, 1999
    Date of Patent: November 28, 2000
    Assignee: Husco International, Inc.
    Inventors: Rollin Christianson, Raud Wilke, Leif Pedersen