Patents Assigned to Samuel Cornelious Evans
  • Patent number: 4222517
    Abstract: The present invention relates to an improved magnetic marker and method for manufacturing same. The marker includes a ribbon of magnetic signal material of relatively low coercivity having coupled thereto at least two control elements of a ferro-magnetic material which may be permanently magnetized by a control signal in order to saturate the strip of first ferromagnetic material, thereby preventing the first ferromagnetic material from generating higher order harmonics when interrogated by a periodic magnetic signal of fundamental frequency.
    Type: Grant
    Filed: September 18, 1978
    Date of Patent: September 16, 1980
    Assignee: Samuel Cornelious Evans
    Inventor: Robert H. Richardson