Patents by Inventor Joseph D. Esker

Joseph D. Esker 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).

  • Prism pole for a surveying system
    Patent number: 5255441
    Abstract: The prism pole consists of an extensible aluminum pole that can be adjusted between a length of 30 and 47 inches. The pole has a hardened steel point on one end thereof and a prism assembly on its opposite end. The prism pole also has a steel point mounted to the prism assembly such that the pole can be turned "upside down" placing the prism assembly approximately 4 inches from the point being measured. To assist in plumbing the prism pole, two level vials are provided, the first being observable when the pole is in the upright position and the second being observable when the pole is in the upside down position.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: October 26, 1993
    Inventors: Bradley C. Burgess, Joseph D. Esker