Magnetic switch assembly

Claim 1

A MAGNETIC SWITCH ASSEMBLY FOR INDICATING THE POSITION OF A CLOSURE MEMBER IN AN ALARM CIRCUIT COMPRISING A SWITCH HOUSING ADAPTED TO BE MOUNTED UPON A STATIONARY FRAME ADJACENT TO A MOVABLE CLOSURE MEMBER, A MAGNET HOUSING ADAPTED TO BE MOUNTED UPON SAID CLOSURE MEMBE ADJACENT TO A FREE EDGE THEREOF, WHEREBY WHEN SAID CLOSURE MEMBER IS CLOSED THE MAGNET HOUSING AND SWITCH HOUSING ARE DISPOSED IN JUXTAPOSITION, TWO FERROMAGNETIC POLE PIECES MOUNTED WITHIN SAID SWITCH HOUSING IN PARALLEL SPACED RELATIONSHIP WITH ONE ANOTHER, A MAGNETIC REED SWITCH, MEANS MOUNTING SAID REED SWITCH WITHIN SAID HOUSING WITH THE AXIS OF SAID REED SWITCH TRANSVERSE TO SAID POLE PIECES, ONE END OF THE REED SWITCH BEING ADJACENT TO EACH OF THE POLE PIECES, ONE OF SAID POLE PIECES HAVING AN OPENING FORMED THEREIN, A LOCAL MAGNET TELESCOPICALLY DISPOSED WITHIN THE OPENING AND EXTENDING PARALLEL TO SAID REED SWITCH TOWARD THE SECOND OF SAID POLE PIECES, A REMOTE MAGNET, MEANS MOUNTING SAID REMOTE MAGNET WITHIN SAID MAGNET HOUSING, THE POLE OF SAID REMOTE MAGNET ADJACENT A POLE PIECE BEING OF OPPOSITE POLARITY TO THE POLE OF THE LOCAL MAGNET ADJACENT TO THE SAME POLE PIECE, SAID LOCAL MAGNET, SAID REMOTE MAGNET AND SAID POLE PIECES FORMING A MAGNETIC BRIDGE CIRCUIT, SAID REED SWITCH INCLUDING A MOVABLE CONTACT SHIFTABLE BETWEEN A FIRST AND SECOND POSITION, SAID CONTACT BEING SHIFED TO SAID POSITION ONLY WHEN SAID MAGNETIC BRIDGE CIRCUIT IS BALANCED.