Patent ID: 6771066
Filing Date: 2004-08-03
Classification: G01R

Abstract:
A fluxgate sensor comprising:a first and a second planar, nonconductive substrate member, each member having an inner and an outer side; a core consisting of a highly magnetically permeable saturable material formed as a flat, closed loop, said core bonded between the inner sides of said first and second substrate members; an excitation coil and core having a magnetic axis and a mechanical axis, said magnetic axis fixed relative to said mechanical axis, said coil comprising a plurality of elongated, electrically conductive tracks placed on the outer sides of said first and second substrate members, each said conductive track extending across said core from inside said core loop to outside said core loop but electrically insulated from the core by said substrate members, first electrically conductive contact means extending from that end of each said elongated track located inside the core loop on the outer side of said first substrate member through said first and second substrate members and connecting with that end of the next adjacent elongated track that is located on the outer side of said second substrate member, second electrically conductive contact means extending from that end of each said elongated track located outside the core loop on the outer side of said first substrate member through said first and second substrate members and connecting with that end of the next adjacent elongated track that is located on the outer side of said second substrate member to thereby form a current path equivalent to that obtained using turns of wire circling said core in a toroidal fashion, and electrical leads to connect said current path to a power source; a signal coil that is arranged to produce an electrical signal in response to a change in the magnetic permeability of said excitation coil and core, said signal coil comprising a bobbin having multiple turns of wire wound thereon, the center of said bobbin having an opening sized and shaped to accommodate passage of said substrate members and to hold said core and excitation coil in a precise orientation relative to said bobbin: and indicia means defining the mechanical axis of said sensor.