Patents by Inventor Rudolph Yeh

Rudolph Yeh 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).

  • Hydraulic valve assembly having an axial flow force balanced spool
    Patent number: 4122868
    Abstract: A directional flow control spool in an open center flow type of valve is provided with primary and secondary flow metering notches in the path of the center flow. The secondary metering notches provide an additional force which assists in the axial shifting of the control spool from a central neutral position.
    Type: Grant
    Filed: January 24, 1977
    Date of Patent: October 31, 1978
    Assignee: International Harvester Company
    Inventors: Gale A. Holloway, Rudolph Yeh, Joseph L. Zagotta