Patent GB-215748-A (GB)
Title: Double control of the combined type for aeroplanes and for like purposes
IPC: B64C13/00
Filed: 1924-05-05
Abstract: 215,748. James, P. N. C. May 12, 1923, [Convention date]. Steering, balancing, and regulating altitude.-In a dual control system of the kind in which, when the control devices at either position are clutched in those at the other position are uncoupled, each of the controlling-members, such as the steering wheels, rudder bars, &c., is connected to a sleeve loosely mounted on the shaft controlling the corresponding control surface, and an axially-displaceable coupling device is provided for clutching each shaft to the corresponding sleeve, all the coupling devices at both positions being interconnected by cables. Means are also provided for automatically locking the controls in their extreme positions, the locking means at both seats being interconnected so that both may be unlocked from either seat. Each seat is provided with (1) an elevator control rocking stick 4, Fig. 1, mounted upon a sleeve 5 rotatable on a common tube 6 and clutchable to a double arm 7 which operates the elevator through cables 8, (2) an aileron control hand wheel 1 rotatable on a tube 2 and clutchable to a chain wheel 3, and (3) a rudder control foot lever 9 mounted upon a sleeve rotatable on a tube 10 and adapted to be clutched to the hub of the rudder control arms 11. The tube 2 is journaled to receive a rod 17, Fig. 3, upon a screwed portion of which is threaded a nut 16 provided with pins 15 which project through slots 14 in the tube 2, and cooperate with two rings to form a bearing for the chain wheel 3. Axial movement is imparted to the nut 16 and the chain wheel 3 by rotating a small hand wheel 19 keyed to the rod 17, teeth 20 on the chain wheel 3 thereby being caused to engage or disengage corresponding teeth on the hand wheel 1. The sleeve 5, Fig. 4, which carries the rocking stick 4, may be clutched to or unclutched from a sleeve 7<1> carrying the elevator control levers, by the axial movement of a coupling sleeve 22, slots in which are adapted to register with corresponding tongues on the sleeve 5. The sleeve 22 is moved by a nut 23, threaded on a rod 24, in the same manner as the chain wheel 3 is moved by the nut 16. In the same way the sleeve carrying the foot lever 9, Fig. 7, is clutchable to the sleeve 11<1> controlling the rudder lever 11, by means of a coupling sleeve 30 moved by a nut 31 threaded upon a rod 32. Rotation imparted to the rod 17, Fig. 3, is transmitted to the rod 24, Fig. 4, by means of drums 25, 26, carrying an endless cable 27 passing through the tubular stick 4. The drum 26 carries a second endless cable 33 which is led through apertures in the tubes 6, 10 and sleeves 5, 11<1>, and passes over a drum 34, Fig. 7, mounted on the rudder control clutching rod 32. The rod 24, Fig. 4, is common to both seats so that movement of the hand wheel 19, Fig. 3, at either station operates all the six clutches, their setting being such that when the clutches of one seat are engaged those of the other seat are disengaged, except during a short period of transition when the clutches of both seats are engaged. The nut 16, Fig. 3, carries a plate 37 pierced with two apertures 38<a>, 38<e>, one of which is entered by a spring-urged locking pin 39 when the clutch is in either of its extreme positions. The coupling sleeves 22, 30, of the other control elements are locked in a similar manner. The locking pins of both stations may be unlocked from either station by rotating a drum 41, Fig. 4, mounted on the stick 4 thereat. An endless cable 43 is led over the drums 41 at each station and over suitably-disposed guide pulleys 44, and acts through bell-crank levers to lift all the locking pins. The pilot at either station can ascertain the condition of the control apparatus by observing the position of the drum 41 and of the coupling sleeves 22, 30.