North seeking and course keeping gyro device

摘要

A gyro device arranged to be mounted in a vehicle and operable selectively as a directional gyro or as a gyro compass, which includes PPa gyro generating signals relative to two measuring directions, an azimuth gimbal mounted with its pivot axis oriented substantially vertically, a drive unit connected to receive the signal from a first position sensor and for pivoting a precession gimbal supported by the azimuth gimbal about a precession axis into a position in which the gyro spin axis is parallel to the pivot axis of said azimuth gimbal, a second position sensor providing a signal representative of the inclination of the precession axis to the horizontal, and a switching member for effecting pivoting of the precession gimbal about the precession axis to bring the spin axis of the gyro into a horizontal orientation for permitting operation of the device as a directional gyro.