Patent GB-543455-A (GB)
Title: Improvements in and relating to gyroscopes and gyroscopic apparatus
IPC: G01C19/26
Filed: 1940-02-06
Abstract: 543,455. Gyroscopic apparatus. SPERRY GYROSCOPE CO., Inc. Feb. 6, 1940, No. 2329. Convention date, March 3, 1939. [Class 97 (iii)] In conjunction with a gyroscope mounted to allow angular movement of the rotor axis relative to a support, means is provided for correcting tilts of the gyroscope during normal operation of the apparatus and also means operating automatically to cage or centralize the gyroscope when the movement reaches a pre-arranged value; the gyroscope may form parts of an aircraft instrument, e.g. it may be applied in the manner described in Specification 543,482, to an automatic pilot as described in Specification 416,813, and may automatically effect control of one or more of the aircraft control surfaces in normal conditions, the control ceasing if the craft approaches stalling incidence &c. Fig. 3 shows part of an automatic pilot comprising a gyroscope 1, having a normally vertical axis, in a gimbal-mounted casing 2 from which a pin 6 projects downwardly within pivoted caging fingers 11 connected by links 13 and mounted on an insulated ring 14. One finger is pivotally connected to an insulated collar 10, Fig. 1, carried by a rod 9 extending in bearings from the plunger 8 of a solenoid 7; energization of the solenoid draws in the plunger, and closes the fingers round the pin 6 to cage the gyroscope. Hand operation of the fingers may be effected by pulling a knob 16 fixed on a shaft 19 carrying a sector 20 engaging between the collar 10 and a second collar 21 on the rod 9. Automatic caging is possible when the knob is in the position shown in Fig. 1 and the shaft 19 is turned to a position such that the sector 20 occupies the continuous-line position shown in Fig. 4. A cam 22 on the shaft 19 then permits contacts 24, 25 on springs 23, 26 to engage, the contacts being in a circuit including the solenoid and a power source. The circuit also includes the fingers 11 and pin 6, and is open until the pin has been moved far enough to engage one of the fingers ; such engagement causes energization of the solenoid and the caging of the gyroscope, and the pin movement necessary to provide it may be varied by adjusting the positions of the collars 10, 21 on the rod 9, thus altering the normal positions of the fingers. Uncaging is effected by turning the knob 16 so that the cam 22 moves the spring 23 to separate the contacts 24, 25, and the sector 20 occupies the broken-line position in Fig. 4. The cam 22 is long enough to maintain the engagement or disengagement of the contacts 24, 25 during the in and out movements of the knob 16. By pushing the knob inwards and turning it, the condition for automatic caging may be restored; a spring-loaded ball 29 and four depressions on the sector position the knob in all its adjustments, and a pointer 17 co-operates with a plate 18 bearing indications of the caging condition. The gyroscope may operate through pick-offs as described in Specification 416,813, and through air relays and oil valves, to control servomotors positioning the ailerons and elevator of an aircraft. Caging of the gyroscope causes the ailerons and elevator to be held in their central positions.