Patent GB-455207-A (GB)
Title: Improvements in or relating to naval gun fire control systems
IPC: F41G5/16
Filed: 1935-01-10
Abstract: 455,207. Gun fire control; sights. SPERRY GYROSCOPE CO., Inc., Manhattan Bridge Plaza, Brooklyn, New York, U.S.A. Jan. 10, 1935, No. 942. Convention date, Jan. 10, 1934. [Class 92 (ii)] A system for use on unstable naval platforms to direct gun fire against rapidly moving targets comprises (1) a gun G, Fig. 3, a predictor or computor I of the type used on land, and a sight 40 controlled in training and elevation by manual means 48, 49 the movements of which are transmitted to a trunnion-tilt corrector X controlled by a master gyroscope H in accordance with the roll and pitch of the ship. (2) means operated by the corrector X to position the sight relatively to its unstable platform, so that the observers using the handles 48, 49 follow only the movements of the target relatively to a stable plane thereby feeding the true present-position angles into the computor, and (3) a second trunnion-tilt corrector Y (similar to X) which receives the true future-position angles from the computor and transmits to the gun the positioning angles in training and elevation relatively to the ship's deck. A second gun G<1> may be controlled in similar manner by a sight 40<1> computor II and trunnion-tilt correctors III, IV, the same master gyroscope H being employed. Figs. 1 and 2 show the form taken by the trunnion-tilt corrector X, which is that described in Specification 455,431. The relative movements between the plane of the ship's deck and the stable plane are materialized by a ring 5 gimbal-mounted on axes 4, 6 on a frame 1 connected to the ship. Pitch and roll movements are conveyed from transmitters PT, RT at the gyroscope H to repeaters PR, RR which control the ring 5. A second ring 15 movable within the ring 5 carries on trunnions 18 a semicircular guide 17 for the outer end of a radial arm 19 which is positioned in elevation and azimuth by the rotation of the handles 49, 48 acting through transmitters ET, TT, Fig. 3, and repeaters ER, TR. The latter operate to elevate the arm 19 by rack gears 26, 28 and to train the arm by gear 23 and shaft 22. A repeater CR controlled from a gyro-compass C and connected by a differential gear 50 with the repeater TR enables the true azimuth to be reckoned from a North-South datum line. The resulting elevation of the guide 17 and rotation of the ring 15 are measured by transmitters E<1>T, T<1>T actuated by toothed gears x, 16 and conveyed to repeaters E<1>R, T<1>R at the sight 40. The gear 16 on the ring 15 is engaged by a pinion on the shaft of a follow-up motor F which is in circuit with contacts 32, 32<1> on the guide 17 arranged on each side of a central insulated gap 32<11>. The circuit through the motor is controlled by the passage of a trolley 31 on the arm 19 to one side or the other of the gap. The motor F is thereby actuated in one direction or the other to position the ring 15 so that the trolley returns to the gap. The gap may be in the form of inner contact portions 32a, 32<1>a with extra insulation 95, 96. The outer contact portions 32b, 32<1>b are then connected to a signal lamp 97 situated near the gun as a warning not to fire until the trolley is at or near its central position. The corrector Y acts, in a manner similar to the corrector X, between the output of the computor I and the repeaters E<1>R<1>, T<1>R<1> at the gun G.