GB753893A - Improvements in or relating to gyroscope systems for use in air navigation - Google Patents

Abstract

753,893. Electric indicating systems. SVENSKA AKTIEBOLAGET GASACCUMULATOR. April 1, 1954 [Oct. 26, 1953], No. 9573/54. Class 40(1) An aircraft artificial-horizon comprises a gimbal mounted, heavy balanced sphere, each of its gimbal shafts being driven through a cynchro-system by the corresponding gimbal shafts of a master (central) gyro. The indicator may be combined with a compass repeater and a rate of turn indicator, the compass repeater being set by a remote induction compass stabilized by the central gyro, and the rate of turn indication being derived from the compass repeater through an eddy current device. Artificial horizon, Figs. 4, 5, 6. A hollow tungsten sphere 32 is fixed to a shaft 35 rotatably mounted by ball bearings in a gimbal ring 36, Fig. 4, carried by a shaft 37 rotatable in the casing 40, which has a glass cover 41 bearing the usual indicator 42 against which the equator line of the sphere is viewed for indicating pitch and bank. The sphere is rotated about a sleeve 52 fixed to the gimbal 36 by a synchro-receiver 53, 58 disposed inside the sphere which, when inoperative is mechanically unbalanced so as to be self-stabilizing. When operative, a magnet 64 inside the sphere is energized to attract its armature 65 and so balance the sphere. A radially movable counterpoise 67, and, if desired, a further counterpoise adjustable perpendicularly to the movements of the armature 65 and counterpoise 67 is/are provided for adjusting balance. Oscillations of the sphere about the sleeve 52 are prevented by a copper eddy current braking ring 71 and cooperating permanent magnet 69. The shaft 37 which is driven by a further synchro-receiver (Fig. 3, not shown), is damped in a similar manner by means of known form of damper disc 72 rotatably mounted thereon. The synchro-systems are energized with three phase current. Compass system Figs. 5, 7. The induction compass is gimbal mounted and vertically stabilized by driving its gimbal shafts through synchros from the corresponding gimbal shafts of the central gyro. It consists of two known compass units disposed with their respective Z-shaped armatures 80, 90 and their stator poles 83, 84 in quadrature. The outputs of the induction coils 82, 91 of the two units are amplified and rectified at 85, 92, respectively, and fed to a motor 87 arranged to rotate the statically balanced compass casing 99 through gearing until the two compass units give equal outputs. The motor shaft is thus positioned according to the magnetic bearing of the aircraft and through a synchro-system drives a graduated drum 122, Fig. 5, to indicate heading. The indicator also comprises signal lamps 125, 126 energized through relays when the three phase supply to the various synchros is switched on. A further drum indicator 129 is mounted concentrically above the drum 122 and is driven thereby through an eddy current drag coupling in opposition to a restoring spring, so that the drum 129 indicates rate of turn.