North-seeking gyro

Claim 1

A NORTH-SEEKING GYROSCOPE COMPRISING: (A) A VERTICAL MOUNTING FRAME; (B) A VERTICAL AXIS AZIMUTH GIMBAL ROTATABLY DISPOSED IN SAID VERTICAL MOUNTING FRAME FOR ROTATION ABOUT A FIRST AXIS; (C) A HORIZONTAL SHAFT ROTATABLY DISPOSED IN SAID VERTICAL AXIS GIMBAL FOR ROTATION ABOUT A SECOND AXIS WHICH IS PERPENDICULAR TO SAID FIRST AXIS; (D) A HOUSING ATTAHED TO SAID HORIZONTAL SHAFT; (E) A HERMETICALLY SEALED CYLINDER DISPOSED WITHIN SAID HOUSING FOR ROTATION ABOUT A THIRD AXIS WHICH IS PERPENDICULAR TO SAID SECOND AXIS; (F) A ROTOR DISPOSED WITHIN SAID CYLINDER FOR ROTATION ABOUT A FOURTH AXIS WHICH IS PERPENDICULAR TO SAID THIRD AXIS; (G) PICKUP MEANS MOUNTED ON SAID CYLINDER AND SAID HOUSING FOR GENERATING AN ELECTRICAL SIGNAL RESPONSIVE TO ANGULAR DISPLACEMENT OF SAID CYLINDER WITHIN SAID HOUSING; (H) A TORQUING MEANS MOUNTED ON SAID CYLINDER AND SAID HOUSING FOR ALIGNING SAID CYLINDER TO THE NULL POSITION WITHIN SAID HOUSING WHEN THE TORQUING MEANS IS ENERGIZED; (I) A LEVEL SENSIGN MEANS ATTACHED TO SAID HORIZONTAL SHAFT FOR GENERATING AN ELECTRICAL SIGNAL RESPONSIVE TO ANGULAR DISPLACEMENT ABOUT SAID SECOND AXIS; (J) A FIRST ELECTROMOTIVE MEANS DISPOSED FOR ROTATING SAID HORIZONTAL SHAFT AND SAID HOUSING ABOUT SAID SECOND AXIS; (K) A SECOND ELECTROMOTIVE MEANS DISPOSED FOR ROTATING SAID VERTICAL AXIS AZIMUTH GIMBAL ABOUT SAID FIRST AXIS; (L) A FIRST MIXING MEANS; (M) A SECOND MIXING MEANS; (N) SWITCHING MEANS CONNECTED TO THE OUTPUT OF SAID PICKUP MEANS AND SAID LEVEL SENSING MEANS FOR COMPLETING THE CIRCUIT BETWEEN THE OUTPUT OF SAID PICKUP MEANS AND SAID TORQUING MEANS AND FR COMPLETING A CIRCUIT BETWEEN THE OUTPUT OF SAID LEVEL SENSING MEANS AND SAID FIRST ELECTROMOTIVE MEANS WHEN SAID SWITCHING MEANS IS IN A FIRST POSITION, AND FOR CONNECTING THE OUTPUT OF SAID PICKUP MEANS TO SAID FIRST AND SECOND MIXING MEANS AND ALSO CONNECTING THE OUTPUT OF SAID LEVEL SENSING MEANS TO SAID FIRST MIXING MEANS WHEN SAID SWITCHING MEANS IS IN A SECOND POSITION; (O) MEANS FOR CONNECTING THE OUTPUT OF SAID FIRST MIXING MEANS TO SAID FIRST ELECTROMOTIVE MEANS FOR ROTATING SAID HORIZONTAL SHAFT; (P) MEANS FOR CONNECTING THE OUTPUT OF SAID SECOND MIXING CIRCUIT TO SAID SECOND ELECTROMOTIVE MEANS FOR ROTATING SAID VERTICAL AXIS AZIMUTH GIMBAL: (Q) A HORIZONTAL SHAFT PICKUP DISPOSED TO SENSE THE DISPLACEMENT OF SAID HORIZONTAL SHAFT ABOUT SAID SECOND AXIS; AND (R) MEANS FOR CONNECTING THE OUTPUT OF SAID HORIZONTAL SHAFT PICKUP TO SAID SECOND MIXING CIRCUIT WHICH GENERATES A SIGNAL RESPONSIVE TO THE OUTPUTS OF BOTH OF SAID PICKUP MEANS.