GB465278A - Improvements in retractable landing gear and the like for aircraft - Google Patents

Abstract

465,278. Mechanism for retracting aircraft parts and apparatus. BRISTOL AEROPLANE CO., Ltd., and FRISE, L. G. Nov. 4, 1935, No. 30495. [Class 4] Means for retracting an aircraft landing wheel, a wireless mast or other apparatus comprises a slot and crank mechanism whereof the crank is driven by the actuating or controlling mechanism, and the link is connected to the wheel or other apparatus to be retracted wherein the retracted and extended positions correspond or approximately correspond to dead-centre positions of the crank. As applied to 'a retractable tail wheel, a wheel 10 is is carried by a fork 11 attached to a tube or bar 12 which may comprise shock absorbing means and which is journalled in bearing brackets 14 mounted at either side of the fuselage 16. A tubular shaft is mounted forward and above brackets 14 and is journalled in bearings 18 secured to the fuselage side walls by brackets 19. This shaft carries at one end a sprocket 20 which may be connected to the gear for retracting the main undercarriage and also carries two arms 21 formed at their outer ends with bearings for trunnion pivots of a sleeve or collar 23 slidable on tube 12. A bolt 25 is provided to limit the travel of sleeve 23 and is arranged so that arms 21 are in their dead centre position or slightly beyond this position so as to secure irreversibility of the mechanism in both retracted and extended states. According to modifications, arms 21 may be replaced by a wheel carrying sleeve 23 at a point on its circumference or the arms may be formed with a pin to engage with a slot formed longitudinally in member 12.