Patent GB-191219864-A (GB)
Title: Improvements in Stabilizing Devices for Flying Machines.
Inventor: SPRATER ADOLF
IPC: B64C1/00
Filed: 1912-08-30
Granted: 1913-07-03
Abstract: 19,864. Sprater, A. Aug. 30. Steering and balancing.-In a device for maintaining the line of flight of a flying-machine when encountering side winds, or when balancing the machine laterally, the steering-rudder is under the control of two wind vanes which may be replaced or have their action augmented by pivoted or sliding masses. One of the wind vanes or masses is placed on the flying-machine a considerable distance from its centre of gravity, and the other is placed at the centre of gravity or on the opposite end of the machine to the first vane or mass. The connexions between the vanes and the steering-plane, except in the modification shown in Fig. 10, are such that when the machine is subjected to a side wind the steering-plane is adjusted parallel with the wind vanes so as to be unacted on bv the relative air current, and when the machine deviates laterally the steering-plane is adjusted to restore the original flight path. Fig. 1 shows two wind vanes 1 disposed at equal distances to the front and rear of the centre of gravity x and controlling directly or through a relay the rudder 121. Each wind vane 1, Fig. 4, may comprise two flat or curved plates inclined to one another and carried by an open frame 2 secured to a spindle 3. In the arrangement shown in Fig. 11, the wind vane 60 is arranged near the centre of gravity and the vane 59 at Lhe front end of the machine. The vanes are connected by the cords shown to pulleys loose on a spindle A. An arm B loose on the spindle A carries a wheel 69 in contact with the pulleys 65, 66, and a wheel 70 in contact with the pulley 67 and a wheel 68 which gears with the rack 71 leading directly or indirectly to the steering-rudder. When the machine is struck by a side gust, as shown by the arrow y, or moves sideways parallel to itself, the vanes move through equal angles, thereby rotating the wheel 69 without displacing the shaft B. The pulley 67 is rotated by the vane 60, and its movement is transmitted by the wheels 70, 68 to the rack moving in the direction of the arrow I to move the rudder parallel to the vanes. When the machine turns about a vertical axis, the vane 59 is moved, when the vane 60, being near the turning centre, is unmoved. The rack 71 is moved in the direction of the arrow II to adjust the rudder to correct the deviation from the line of flight. In place of vanes, masses may be arranged so as to be displaced laterally against the action of springs when the machine deviates. In one modification, two sliding masses 97, 98, Fig. 13, and a wind vane 112 are used to control the rudder 121. The mass 98 and vane 112 are arranged close to the centre of gravity of the aeroplane and the mass 97 is arranged near the tail. A shaft 79 carries loosely mounted thereon, a combined sector 109, 110, a lever 115, and pinions 104, 102, 101, 103. Pinions 105, 106 are loosely mounted on a shaft 107 freely pivoted on the shaft 79, and a pinion 108 is freely mounted on the lever 115, which is connected to one part 117 of a double valvegear of the servomotor 94. The weight 97 is connected by a crossed cord 99 to the pinion 101 and the weight 98 is secured to the rack 100 gearing with the pinion 102. A pulley 119 on the shaft of the servomotor is connected to the rudder 121 and a pinion 118 on the shaft gears with the pinion 104. When the machine moves sideways, parallel with itself, the two weights 97, 98 transmit their equal and similar movements to the pinions 101, 102, which are moved oppositely and rotate the pinion 105 without moving its shaft 107 about the shaft 19. The pinion 103 and the valve member 114 are not moved since the pinion 106 is held by the stationary pinion 104, which is locked by the pinion 118 on the shaft of the servomotor. The wind vane 112 is also moved, say in the direction of the arrow w, and rotates the pinions 109, 108. The pinion 108 rolls on the pinion 104 and moves the lever 115 to adjust the slide 117 to admit compressed air from the pipe p to the servomotor. The movement of the servomotor operates the rudder 121 and, through the pinions 118, 104, 108, returns the slide 117 to its normal position. When the machine turns about a vertical axis, the wind vane 112 and weight 98 being near the centre of gravity of the machine are unaffected, and the weight 97 by its inertia moves the pinion 101 and, through the pinions 105, 106, the pinion 103 which adjusts the valve gear 114. In another modification, the weights are pivotally mounted to swing laterally. In the modification shown in Fig. 10, masses 47, 53 secured to frames 48, 54 are adapted to slide laterally under the control of springs. The frame 48 is provided with a rack 50 gearing with a pinion 51 which also gears with a second rack 52 connected by cords 55 to the frame 54. The pinion 54 is mounted on the rod 56 which actuates the rudder either directly or through a relay. When the machine slides sideways the masses 47, 53 have equal movements in the same direction and the rack 56 is unmoved. When the masses move unequally, as occurs when the machine turns about a vertical axis, the rudder is adjusted to correct the deviation of the machine.