Patents by Inventor John H. Bolson, Sr.

John H. Bolson, Sr. 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).

  • Self-orienting passive marker structure
    Patent number: 4712094
    Abstract: A passive marker including a tuned circuit having an inductance and a capacitance carried by a carrier enclosed within a hollow sphere that is partially filled with a liquid to freely float the carrier. The inductance includes a coil which, when the carrier is floating, positions the axis of the coil so it is closer to the vertical than the horizontal. The passive marker is of a type that is buried relative to portions of utilities such as gas, telephone, water and power lines, for use in locating such portions when necessary.
    Type: Grant
    Filed: May 29, 1986
    Date of Patent: December 8, 1987
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: John H. Bolson, Sr.