Patent ID: 6313724
Filing Date: 2001-11-06
Classification: H01H

Abstract:
An apparatus that senses proximity between physical elements, comprising:a magnetic pole array comprised of at least one magnetic building block each containing two similar size and proximate magnets with a north pole on one end and a south pole on the other end where an imaginary line between the centers of said poles is the axis of said magnet, andwhere said two magnets proximate and are positioned in a manner where their axes are substantially parallel and the north pole of the first magnet is adjacent to the south pole of the second said magnet--first set of adjacent poles--and the south pole of the first magnet is adjacent to the north pole of the second said magnet--second set of adjacent poles; an imaginary plane perpendicular to the said axes and substantially centered between the first and second said sets of adjacent poles defines an equatorial plane where a magnetic field emanating from the first said set of adjacent poles is opposite in direction and close in intensity to magnetic field emanating from the second said set of adjacent poles and substantially cancel each other out--a balanced state of said magnetic fields where a net intensity of all magnetic fields emanating from said magnetic building block is negligible;at least one magnetic sensor positioned substantially on said equatorial plane wherein said balanced state an output of said sensor is not activated due to insufficient intensity of magnetic field; anda shunt made of permeable material when placed in proximity of one said set of adjacent poles of said magnetic pole array reduces the magnetic field emanating from said set of adjacent poles and net intensity of all magnetic fields at said equatorial plane emanating from said magnetic building block is sufficient to activate the said sensor--said balanced state is changed to an unbalanced state where placement of said shunt is an input to said apparatus affecting said output.