Patent GB-379109-A (GB)
Title: Improvements in or relating to navigating apparatus for aeroplanes
IPC: G01C19/42
Filed: 1931-09-10
Abstract: 379,109. Steering and balancing aircraft. MARMONIER, L., 146, Avenue Felix Faure, Lyons, France. Sept. 10, 1931, No. 25454. Convention date, Sept. 16, 1930. [Class 4.] Apparatus for stabilizing an aeroplane comprises pendulous gyroscopic groups for maintaining a horizontal platform and a fixed direction in azimuth which act upon the three controls of the aeroplane through electric or other servomotors subject to the following corrections and adjustments :-(1) When a turn is to be made, movement of the pilot's control automatically disengages the gyroscope frame and locks it to the machine and applies a correction to the aileron control ; (2) an inertia device counteracts the effect of centrifugal force upon the lateral stabilizing gyroscope during a turn and lateral accelerations, and also applies a correction for maintaining correct bank ; (3) a wind vane maintained in a vertical position by the gyroscopic groups appllies a correction to the aileron control in accordance with lateral variations in the direction of the air current ; (4) the elevator control is subject to an overriding manual control and also to control by a wind vane which initiates a dive should the air speed fall below a limit appropriate to the attitude of the machine at the time ; and (5) a correction also may be applied to the elevator control to meet variations in drag. The servomotors have follow-up gear to proportion their response to the displacement of the control element, and are available to the pilot for manual control of the elevator and rudder. The gyroscopic groups used are described in Specification 290,203, [Class 97 (iii), Thermometers &c.], and only portions of the gyroscopic apparatus are shown. (1) A finger 15, Figs. 1 and 3, co-operating with contacts 16, 17 on a disc 18 controls a servomotor 36 for actuating the rudder, connections to an arm 43 on a differential gear 31, 32, 33 causing the disc 18 to follow up the finger 15. This finger is mounted on a spindle 14 which is normally coupled by a plate clutch 21, 23 to a bevel wheel 24 in mesh with a wheel 25 controlled by the gyroscope so as to maintain the aeroplane on a set course. A lever 30 pivoted about a central fixed tube 19 carries a bevel wheel 29 in mesh with a normally fixed wheel 28 and with the gear 31 which is a double bevel wheel. Movements of the lever 30 consequently move the disc 18 and a turn is initiated. Simultaneously a contact 34 on the lever completes a circuit through one or other of two sectors 35, 35<1> to energize an electromagnet 26 which disengages the clutch 21, 23 and locks the spindle 14 to the frame. Small corrections in direction may be effected without disengaging the gyroscope by means of a .worm 50 acting on a worm wheel 51 to turn the normally fixed wheel 28. Movement of the lever 30 also applies an appropriate correction to the aileron control through the link 73 and differential gear 53, 54, 58 acting upon the finger 59 of the aileron control. (2) A weight 1, Fig. 1, is mounted by rollers 7 upon parallel bars 5, 5<1> carried by a frame on a longitudinal shaft 2. The weight is centred in the frame by adjustable springs 8, 9. The shaft 2 is coupled to the shaft controlled by the gyroscopic group by arms 3, 3<1> and a link 4. Any displacement of the weight 1 due to centrifugal force or other lateral acceleration can be adjusted to counteract the effect of such acceleration upon the pendulous mass of the gyroscopic group f. Movement of the weight 1 by moving a rack 80 in mesh with a pinion 81, turns a wheel 82 of a differential gear and a link 84 is moved to effect a movement of the finger 59 through the differential gear 47, 52, 53. A contact sector 60 co-operating with the finger 59 is coupled to the servomotor 62 by a link 65. (3) A wind vane 90 is carried by arms from a vertical spindle 93 which is maintained vertical by connections 96, 92, 97, 99 from the gyroscopic group. The vane is counterbalanced statically by weights 100, 100<1>. Lateral movements of the vane move a shaft 104 and by turning a wheel 105 of the differential gear connected to the link 84 applies a correction to the aileron control. (4) Fig. 2 shows the elevator control which has a double differential gear whereby a manual control lever 156 may control the servomotor or a device for measuring the lift may actuate the servomotor to initiate a dive should the lift fall to a dangerous value. An aerofoil 115 is pivoted about its centre of pressure on a shaft 116 and is maintained at a constant incidence by a tail fin. The shaft 116 is carried by an arm 117 connected to a doublearmed lever 119 connected by cables 120, 120<1> to a lever 121 having an inclined arm 122 carrying a weight 123. The inclination of the arm is adjusted to suit the aeroplane and ensures that at varying attitudes of the machine the moment exerted on the lever 121 varies. An extension of the lever 119 works in a slot 124 so that as long as the requisite lift is maintained no movement takes place, but as soon as the lift is insufficient to raise the lever 117 against the moment of the weight 123 a linkage 164, 165 is moved to initiate, a dive. (5) A member 126 subject to wind pressure may be mounted on a lever 129 connected by cables 132, 132<1> to a lever 131 having an inclined arm 134 and a weight 180. The effects of variation of lift and drag are combined by the differential gear shown, the planet pinion actuating the link 164.