Patent GB-778163-A (GB)
Title: Manual controller for an automatic pilot system
IPC: G05D1/00
Filed: 1954-05-14
Abstract: 778,163. Automatic steering control systems. BENDIX AVIATION CORPORATION. May 14, 1954 [June 9, 1953], No. 14251/54. Class 38 (4). In an aircraft automatic pilot displacement of a manual turn control first renders a directional reference ineffective, further displacement being necessary to operate signal generators introducing signals into roll and yaw channels to effect the turn. In Fig. 1 course deviations are detected by an earth inductor compass 63, A.C. signals from which are applied through an inductive device 66 to an amplifier 68, output from which operates a two-phase servomotor 69 until it drives the rotor of inductive device 66 to a null position. Servomotor 69 adjusts the rotor of an inductive device 62 so as to apply an A.C. signal to an amplifier 21 output from which causes a servomotor 52 to adjust the ailerons 10 and thereby correct course by banking the aircraft. Position and rate followup is provided by an inductive device 23 and a generator 22 coupled to servomotor 52. Roll is detected by a pick-off 61 of a gyro-vertical 24 which introduces an A.C. signal into the input of amplifier 21 so that ailerons 10 correct roll. Pitch is detected by a pick-off 44 of gyrovertical 24 which introduces an A.C. signal into the input of an amplifier 41 the output of which causes a two-phase servomotor 54 to adjust the elevators 12 and thereby correct pitch. In order to produce appropriate deflection of the rudder during a turn, pick-offs 34, 35 associated with a damped pendulum sideslip detector 90 and a rate of turn gyro 85 respectively, introduce A.C. signals into the input of an amplifier 31 the output of which controls a two-phase servomotor 53 adjusting the rudder 11. Position and rate follow-up is provided for servomotors 53, 54 by inductive devices 33, 43 and generators 32, 42. Direct manual control of rudder, elevators and ailerons may be effected by a controller 13. To obtain automatic pilot operation a switch 104 is closed to energize solenoid-actuated clutches 101 which couple servomotors 52, 53, 54 to the control surfaces. If a switch 108 is moved to the position shown when the aircraft is at any altitude a clutch 96 is energized so that aneroid 95 is effective to maintain the aircraft at that altitude by operation of an inductive device 45, signals from which are introduced into the input of elevator control amplifier 41. If switch 108 is moved to its other position, clutch 96 is de-energized to disengage the altitude control and a clutch 139 is energized so that knobs 132 are effective to control pitch manually by operation of an inductive device 47 introducing signals into the input of elevator control amplifier 41. When it is desired to change course by manual control of the automatic pilot movement of a knob 130 from a central position first opens a switch 107 to de-energize a clutch 70 and disengage the azimuth control. Further rotation of knob 130 then operates an inductive device 27 which introduces a signal into the input of the aileron control amplifier 21 to turn the aircraft by banking. Knob 130 also operates an inductive device 37 which introduces a signal into the input of rudder control amplifier 31 to produce a rudder deflection suited to the turn. Spring- loaded levers 97, 111 and 220 ensure that inductive devices 45, 62 and 47 return to a central position when the automatic pilot is disengaged and solenoids 110 are de-energized. Constructional details of a compact controller incorporating knobs 130, 132, self-centring inductive devices 27, 37 and 47 and switch 108 are described with relation to Figs. 2-6 (not shown). A lost motion device ensures that after switch 107 has been cam-operated by movement of knob 130 from a central position, further rotation is necessary before rotation of the inductive devices commences. Specifications 662,831, 662,853 and 778,161 are referred to.