Arrangement in spring loaded gyroscopes for inertia navigation

Claim 1

IN A SPRING LOADED GYROSCOPE FOR INERTIA NAVIGATION HAVING A FIRST GIMBAL HAVING A SUPPORTING AXIS AND A SECOND GIMBAL PIVOTALLY MOUNTED ON ITS SUPPORTING AXIS WITHIN SAID FIRST GIMBAL, A ROTOR WITHIN SAID SECOND GIMBAL WHEREBY ROTATION OF THE ROTOR PIVOTS SAID SECOND GIMBAL WITHIN SAID FIRST GIMBAL, MEANS FOR SENSING THE DISPLACEMENT OF SAID SECOND GIMBAL WITH RESPECT TO SAID FIRST GIMBAL, AND A TORQUE MOTOR DRIVINGLY CONNECTED TO PIVOT SAID FIRST GIMBAL ABOUT ITS SUPPORTING AXIS IN RESPONSE TO THE DISPLACEMENT OF SAID SECOND GIMBAL; AN ARRANGEMENT FOR RESILIENTLY COUNTERACTING PRECESSION FORCES OCCURRING ON SAID SECOND GIMBAL AND COMPRISING SPRING MEANS ACTING UPON SAID SECOND GIMBAL TO APPLY A TORQUE THERETO, SAID SPRING HAVING THE CHARACTERISTIC THAT THE DERIVATIVE OF THE FORCE EXERTED BY THE SPRING WITH RESPECT TO THE ANGLE BETWEEN THE AXIS OF ROTATION OF THE GYROSCOPE ROTOR AND THE SUPPORTING AXIS OF SAID FIRST GIMBAL IS SUBSTANTIALLY EQUAL TO THE DERIVATIVE OF THE PRECESSION MOMENT FROM THE SPRING WITH RESPECT TO THE SAME ANGLE.