Fecha de publicación: 06/11/1913 Fuente: WIPO "pollen" 23,846. Pollen, A. H., and Isherwood, H. Oct. 26. Gyroscopic apparatus employed for indicating a change of direction in azimuth comprises two similar gyroscopes 3, 4 capable of being used as such alternately, automatic means for throwing one gyroscope out of action and the other one into action before the period during which one gyroscope maintains unaltered its plane of rotation has elapsed, and automatic means for restoring the one gyroscope to its normal state as regards speed and plane of rotation during the working term of the other gyroscope. A continuously rotating shaft, through mutilated gears 24 engaging gears 25, rotates alternately the two cam shafts 21, one for each gyroscope. These shafts 21 carry cams which through a three-armed lever 26 connect one gyroscope to the indicating-means 44, simultaneously disconnecting the other; cams on the shaft 21 through gears and tappets centre the frames 3 and 45 of the disconnected gyroscope and insert a cone 66 into a hole 67 in one end of the horizontal axis to ensure restoration of plane, upon which the air cock opens and restores the speed; the cone 66 is withdrawn, and the lever 26 connects the restored gyroscope to the indicator and disconnects the other gyroscope.