Accession Number : ADD012584

Title :   Two-Headed DC Magnetic Target Proximity Sensor.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Heemstra,Frank W

Report Date : 29 Jul 1986

Pagination or Media Count : 9

Abstract : A magnetic proximity sensor for detecting the proximity of a laterally moving magnetized target moving along a translation axis which is parallel to a line joining the targets magnetic poles, including: two ring-core flux-gate magnetometers disposed adjacent to each other with their axes of sensitivity in parallel, with both axes perpendicular to the magnetized target translation axis. The energizing coils of the flux-gate magnetometers are driven by an ac signal at frequency fo. The signal on the detecting coils in each flux-gate magnetometer is applied to a phase comparator via a bandpass filter tuned to the second harmonic of fo. When the signals applied to the phase comparator are of opposite phase, then the center plane equidistant from the target's magnetic poles is between the two axes of sensitivity of the magnetometers. When the signals are of the same phase, then the target's center plane is laterally outside of the these two axes.

Descriptors :   *PATENTS, *MAGNETOMETERS, *MAGNETIC DETECTORS, *PROXIMITY DEVICES, MAGNETIC FIELDS, FLUX(RATE), MOVING TARGETS, DIRECT CURRENT, MULTIPLE OPERATION

Subject Categories : Magnetic & Electric Fld Detection & Detectors
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE