Patents by Inventor Lyle E. Harper

Lyle E. Harper 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).

  • Patent number: 5787992
    Abstract: The spring trip assembly has lever mechanism between the shank and the compression spring which causes the trip-out force of the shank to drop sharply once the relatively high, initial trip-out force level has been reached, thus permitting the shank to slide up and over obstructions without breakage. The compression spring is actuated from both ends simultaneously as the shank rises so that although the trip force drops off quickly, energy also builds up quickly in the spring. Thus, the trip force does not drop as low as it otherwise would, assuring that ample return force is available to reset the shank down into the soil in its working position. Various components of the assembly can be removed and replaced easily without disassembling the entire unit from the tool bar.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: August 4, 1998
    Assignee: Morris Industries Ltd.
    Inventors: David A. Dobson, Lyle E. Harper