Patent GB-274268-A (GB)
Title: Improvements in or relating to gyroscopic apparatus
IPC: G01C19/38
Filed: 1926-07-03
Abstract: 274,268. Gray, J. G. July 3; 1926. Gyroscopic apparatus. - Apparatus for defining the vertical on a moving body consists of a gyroscope. attached to a vertical frame by vertical pivots with its axis of spin horizontal and at right-angles to the frame which is attached to the moving body by horizontal fore-andaft pivots. The gyroscope spins in a clockwise direction as seen from the starboard side of the vehicle and means are provided to adjust the amount of gravity control possessed by the frame so that the angular momentum of the gyroscope may be equal to MVh, M and V being the mass and linear velocitv of the system mounted on the fore-and-aft pivots and h the distance of the centre of gravity of this system below the axis of the said pivots. The gyroscope is stabilized with respect to the frame by couples applied about the fore-and-aft pivots. In the form shown in Figs. 1 and 2, 1 is the gyroscope mounted on vertical pivots 2 in the frame 3 supported by horizontal fore-and-aft pivots 4 in pillars 5 fixed on the vehicle. Vanes 8 8<1> are driven by the gyroscope, through reduction gears 6, 6<1> and apply reaction torques to the gyroscope casing in the plane of the flywheel, or in a parallel plane in order to damp out the precessional motion of the gyroscope. The gyroscope is centralized with respect to the frame by springs 9, and the centre of gravity of the system carried by the pivots 4 can be adjusted by a slidable weight 10 operated by a screw 11. In the form shown in Fig. 4 the vanes 8 are mounted on a fore-and-aft axis and are driven bv a reversible motor 6<2> controlled by a contact roller 19 on an arm 13 secured to the axis 2 and co-operating with a. pair of conducting segments 15 separated by an insulating strip. Figs. 7 and 8 show a form in which the damping is produced by an air blast derived from the interior of the casing 1. The nozzle 16<1> lies normally between two shoots 17', 18 carried by the frame 3, these shoots being turned out at right-angles as shown. Precession of the gyroscope causes the nozzle to deliver air into one of the shoots, thereby setting up a reaction damping torque. Alternatively; the casing may carry two nozzles turned out at rightangles, the mouths of the nozzles being adapted to be closed by pivoted shutters operated by electromagnets the circuits of which are arranged to be controlled by precession of the gyroscope in the same way as that of the motor 6<2> in Fig. 4. An arrangement which increases the natural period of the gyroscope pendulum, and is therefore particularly suitable where V is small and h consequently relatively large, is shown in Fig. 11. A main gyroscope 1 is attached as above to the frame 3 by vertical pivots 2 and the frame is supported by horizontal pivots 4 in pillars 5. Vanes 8 are operated by a reversible motor 6<4> which is controlled as in Fig. 4. The frame 3 also suports on vertical pivots 2<3> an auxiliary gyroscope 1<1>, one of these pivots being extended and provided with a worm wheel 29 which can be operated by a worm 30 so that the gyroscope 1<1> can be forcibly turned until its axis makes any desired angle # with the plane of the frame 3. The gyroscopes are preferably identical and rotate at the same speed in opposite directions. The effect of the auxiliary gyroscope is to apply a couple, depending on the angle #, when the vessel turns in azimuth and therebv increase the period of the pendulum. The above device is also available to define the vertical when the pivots 4 are arranged transversely of the vessel, provided that 0 = 90‹. The gyroscope 1<1> may be attached to the frame 3 by fore-and-aft pivots 32, Fig. 12, and centralized by springs 33, and then functions as a turn-indicator. In this case contacts 34, 35 may be provided controlling, for example, a steering-device. Specifications 186,655 and 221,006 are referred to.