Patent GB-146548-A (GB)
Title: Improvements in means for controlling aircraft
IPC: B64C13/24
Filed: 1918-05-31
Abstract: 146,548. Ruck, R. M. May 31, 1918. Steering, balancing, and regulating altitude.- The controls of an aircraft are operated mechanically step by step by a relay apparatus, driven by the main engine or by an auxiliary wind or other motor, in accordance with movements made by the pilot, the relay being of the type described in Specification 112,480, [Class 80 (ii), Gearing, Variable-speed &c.], as applied to gearchanging on motor-vehicles. A cut-out device may be provided to allow direct manual control when desired. The apparatus shown is a duplex one to effect independently the operation of two movable members on the aircraft through the respective pairs of connexions 19, 20 and 19*, 20*, which are operated by the positive step-by-step movements of sliding parts 16, 16* under power transmitted from the continuously-rotating shaft 11 in accordance with the movements of the pilot's controlling-cables. Regarding only the parts in connexion with the upper slide 16, this member is provided with series of notches 21, 22 on its lower corners, arranged to engage respectively with bell-crank levers 23, 24 when one or other is rocked about its shaft 25, 26, such movement also bringing one of the rollers 29, 30 into position to engage a face-cam 31, 32 on the main shaft. Either lever is thus caused to slide along its shaft, and carry the part 16 with it, but when disengaged it is returned to its initial axial position by a spring. Both levers tend, under spring action, to come into the position for engagement, hut are held out by rocking-mechanism releasable by the pilot, when their movements are determined by timing-mechanism comprising edge-cams 33, 34 and a disk 35 having face flanges 37, 38 upon the main shaft, and by levers 39, 40 upon the rocking- shafts engaging the cams 33, 34, and presenting projections 43, 44 to co-operate with the flanges 37, 38. Considering only the one lever 23, the action of the device is as follows. A pull exerted by the pilot upon the cable 53 moves over the link 55, Fig. 2, and through a pin-and-slot connexion 49<a> rocks a link 49 upon its pivot 51, and by removing the stop 47 from engagement with a nose 45 on the locking-lever 39, releases the latter. As soon as the timing-cam 33 (which is similar to the cam 34 and similarly placed) has moved a little in the direction of the arrow from the position shown, the shaft 25 is rocked over by a spring 27, Fig. 3, attached to an arm 28 secured to it at the other end of the casing. The lever 23 is thereby introduced into a notch 21 in the slide 16, and the roller 29 is brought into a position to engage with the face of the main cam 31. At the same time, the slide is released by the withdrawal of a pin 57 from its engagement with one of a series of holes 56, by means of an arm 63, Fig. 3, which moves with the rockshaft. The first half-revolution of the main shaft corresponds with the idle portion of the main cam, after which, just as the active portion comes into position, the flange 37 on the disk 35 comes over the rib 43 on the lever 39, holding it down until the axial movement of the lever 23 produced by the cam is completed, and the slide has been moved through one step. The nose of the cam 33 now returns to the position shown in Fig. 2, and raises the lever 39, this movement being possible since the flange 37 has now cleared the projecting 43. If the pull on the cable 53 is not maintained, the link 49 returns to its original position, and locks the lever 23 in the raised or disengaged position, in which it is clear of the notches 21 in the slide, which is now secured by the engagement of the pin 57 in that hole 56 which is next to the one it formerly occupied, the action of the cam 31 having thrust the lever axially to the extent of one notch, carrying the slide with it. Finally, as soon as it clears the notch on the slide, the lever 23 is caused to slide back along its shaft 25 to its original position by a spring 31<a>. A further pull upon the cable 53 causes the slide again to move through one space in the same direction, while a pull upon the cable 54 moves it through one step in the reverse direction by a similar series of stages. The flanges 37, 38 prevent the accidental displacement of the parts during the actual course of the operation, and the nature of the pin-andslot connexion prevents both levers 23, 24 from coming into action simultaneously. A similar set of levers &c. operate the lower slide 16* independently of the action of the upper slide. A control 67, acting through the lever 62, may be set by the pilot to withdraw the locking-pin 57 from its engagement with the slide, and so set it free for direct manual operation. The spring 31a may be arranged to give the necessary rotation to the shaft 25, the spring 27 then being dispensed with.