Integrated magneto-seismic sensor

Claim 1

An integrated sensor assembly for the detection of intrusion disturbances, of the variety having magnetic signal or seismic signal characteristics, when said sensor assembly is emplaced in a selected area comprising: an all encompassing casing of nonmagnetic material adapted for emplacement in seismic relation in a selected area, a magnetic armature yoke structure rigidly supported in seismic relation within said casing, said armature yoke structure having a magnetic path consisting of a first section, a second section, and a defined air gaps section between a first selected end of each of said first and second sections, and a third section connected to the opposite end of each of said first and second sections and disposed therebetween, said first, second, and third sections of said magnetic armature yoke being of a material having a high initial permeability, said third section having an inductance means wound thereabout such that changes in magnetic flux conditions in said air gaps section produces a first signal, having a frequency within a first selected frequency range, across said inductance means representative of said changes in magnetic flux conditions, and an elongated pendulum member, nonmagnetic means for pivotedly attaching said elongated pendulum member to said yoke structure in the vicinity of said third section thereof, the length and configuration of said pendulum member and the pivot connection of said means for attaching adapted such that said pendulum member extends through and beyond said air gaps section and, in at least one selected orientation of said casing, is pivotedly moveable within said air gaps section in response to seismic movement of said casing, at least that portion of said pendulum member within said air gaps section being of a material which creates a magnetic flux disturbance when said pendulum member moves relative to said first selected ends of said first and second sections of said yoke structure within said air gaps section and produces a second signal, having a frequency within a second selected frequency range, across said inductance means representative of the movement of said pendulum member.