Patent ID: 6529008
Filing Date: 2003-03-04
Classification: G01V

Abstract:
An electromagnetic induction coil sensor, comprising:a casing with high magnetic permeability; a magnet disposed within the casing, the magnet having a central hole; a core with high magnetic permeability disposed within the central hole of the magnet, the core being in physical contact with the casing; a multi-loop coil of conductive wire disposed within the central hole of the magnet encircling the core, the multi-loop coil having impedance of at least approximately 500 ohms in order to make the multi-loop coil highly sensitive to external magnetic fields, the multi-loop coil being insulated from the magnet, and having connection leads, whereby connection is made to a conductive circuit; and remaining space within the casing being filled with a non-conducting resin, thereby securing the core, the multi-loop coil and the magnet against relative movement within the casing.