Patents by Inventor Wilford W. Pfeffer

Wilford W. Pfeffer 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: 4846445
    Abstract: Disclosed is an apparatus for extracting the fence post and the like from the earth. The invention is preferably used in conjunction with a tractor, backhoe or other piece of mobile equipment having hydraulical controls for supplementally attached equipment. The hydraulic controls of the tractor are connected to a hydraulic cylinder on the apparatus capable of creating approximately one foot of horizontal travel within the apparatus. Through the use of a fixed length of cable and a series of sheaves, this approximate one foot of horizontal travel is translated into approximately five feet of vertical travel. There are self-clamping jaws which automatically engage a fence post or the like when the hydraulic cylinder is used to actuate the lifting mechanism. In operation, the tractor is merely backed up to a fence post and the hydraulic controls operated to actuate the hydraulic cylinder thereby engaging the fence post and extracting it all in one motion.
    Type: Grant
    Filed: April 6, 1987
    Date of Patent: July 11, 1989
    Inventor: Wilford W. Pfeffer