GB542530A - Improvements relating to the remote control of parts actuated through flexible power transmission mechanisms - Google Patents

Abstract

542,530. Bowden mechanism. TONDEUR, R., and BOWDEN (ENGINEERS), Ltd. July 10, 1940, No. 11496. [Class 136 (i)] [Also in Groups XXIV and XXXIII] Relates to remote control of parts actuated through flexible power transmission members At the control station A, a winding drum 1 is provided and at the remote station B a similar drum 3. Motion is transmitted to the drum 3 from the drum 1 by flexible cables which, as shown constitute the inner members 4, 4a of twc Bowden mechanisms the outer members 5, 6 of which take their abutment in recesses 10, Fig. 2 in screwed members 11 at the control end and in recesses 12 in guide members 13 at the remote end. The screws 11 engage sockets 15 in guide members 17 and at the remote station, eact guide member houses a spring 19 which can be compressed by rotating the corresponding screw at the control station. The cables have nipples which engage slots 9a in the drums. The ends of the outer Bowden members and the bores ir the screws 11 may be flared to prevent injury tc the cable. The drum may be provided with helical grooves 25 .. 28 and the guide members 13, 17 are moved axially to keep up with the coiling by screw threads ,29, 30 actuated from the drum spindles through gearing 33, 34 and 35, 36 the spindles gearing with nuts 31, 32 integral with the guides each pair of which is joined by sleeves 37, 38, which slide over fixed rods 39, 40. Further each guide structure has channel portions 41 .. 44 co-operating with fixed guide rods 45 .. 48. The pitch of the screws is such as to make the transmission irreversible. The relative motior of winding, drum and guides is utilised for actuating the member at the remote end and, for this purpose, a link 56, Fig. 1 connected to the guide structure 13 is pivoted to an arm 55, Fig. 4, on the axle 54 of a trimming tab 50 of an aeroplane rudder 51. The remote drum may be arranged within the hollow rudder. The amount by which the tab is adjusted may be indicated by a rotatable dial 81 and fixed pointer 82. The actuating handle 2 carries a gear 83 meshing with gears 84, 85 carried by an arm 86 and engaging a fixed annulus 87. The dial is attached to the arm 86. In an alternative form of indicator a length of incompressible flexible tubing moves along a bore in a tube. In a further modification, the cable guides are stationary and the drums move endwise. In a still further modification, the cables from the control drum pass to slide blocks in a pair of junction boxes. From each block a Bowden mechanism passes to a drum device on each of two trimming tabs of the elevators of an aircraft. The outer members may have parts removed, the bared cables passing over guide pulleys. Alternatively, the cable may pass through one or more fixed rigid tubes 100, Fig. 4 each end of which would form an abutment for the outer members.