GB897627A - Control apparatus for aircraft - Google Patents

Abstract

897,627. Fluid-pressure servomotor control systems. SPERRY GYROSCOPE CO. June 10, 1959 [June 23, 1958], No. 20054/58. Addition to 828,785. Class 135. Control apparatus for aircraft having a control surface in at least two independently-movable portions 11, 12, each having a main actuator 13, 14 moved in dependence on a signal applied to the associated actuator controlmeans 1, has a first auxiliary actuator 22 for applying a signal from a first automatic pilot 21 to the control means of one main actuator 14, a second auxiliary actuator for applying a signal from a second automatic pilot to the control means of a second main actuator 13, and a connection 5, 27, 19 from the output of the main actuators effective during an automatic mode of operation, i.e. when one automatic pilot is in control, e.g. that in the lower control channel A of the Figure, to apply a signal, corresponding to the signal from the automatic pilot to its associated actuator, to each of the other main actuators, e.g. in upper channel B. With switch 6 moved to cut out the automatic pilots and release the holding means 11, movement of the manual controller 17 actuates both control means 1 via floating lever 19, links 3 and 7, and spring boxes 4, follow-up from the actuator outputs occurring at 5, 27, 19. Should one actuator fail, control passes through the remaining actuator. On moving switch 6 to bring in the automatic pilot in channel A, a solenoid 13 moves a lever 10 to lock a slide 8 carrying the pivot of floating lever 19 to link 3 of actuator 14. The automatic pilot controls surface 12 via auxiliary actuator 22 and main actuator 14, follow-up occurring via potentiometer 15 and, via links 5 and 27, the lever 19 turns on its fixed pivot at 8 to move lever 17 against the artificial feel device 2 and moves the link 3 pivoted to the unlatched upper slide 8 whereby the control surface 11 is correspondingly moved via control means 1 and main actuator 13. The other automatic pilot in channel B acts as a standby pilot which may be used on failure of the automatic pilot in channel A and which monitors the latter pilot via a comparator 16 so that any discrepancy between them actuates a warning or a cut-out. Surfaces other than 11, 12 may be actuated through channels similar to A, B but containing no automatic pilot. They would be operated from the manual controller 17 or via the feedback from the main actuator under automatic pilot control. A number of comparators 16 may compare signals at corresponding positions along the two channels. In another embodiment, the control surface may have more than two movable portions, but only two will have control channels identical with sections A and B, the others having no autopilot 21, auxiliary actuator 22 or differential link 7 and being controlled manually through channels similar to A and B or automatically by movement of the lever 17 resulting from the connected autopilot in channel A or B.