Patents by Inventor Ralph H. Curtis

Ralph H. Curtis 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).

  • Gravity actuated guiding device for farm machines
    Patent number: 4363174
    Abstract: A gravity-actuated guide for row crops which mounts on a tractor front axle to enable the operator to compensate for changes in transverse slope by steering the tractor and thereby correctly position cultivating equipment behind the tractor in relation to the rows.
    Type: Grant
    Filed: August 11, 1980
    Date of Patent: December 14, 1982
    Inventor: Ralph H. Curtis