GB558751A - Improved mechanism for retracting and automatically locking undercarriages of aircraft - Google Patents

Abstract

558,751 Aircraft alighting-gear. MARTIN, J., and MARTIN-BAKER AIRCRAFT CO., Ltd. July 15, 1942, No. 9819. [Class 4] The wheel-carrying leg of an oleo shockabsorbing retractable undercarriage for aircraft is strutted in the lowered position by a collapsible radius rod having two hinged arms 6, 7, shown in Fig. 2 in a dead-centre position, the connecting joint being offset from the axis of the strutted radius-rod; the arms are spring- held in the coaxial position when strutting and are also locked by a lock in the knuckle-joint connection of the arms which is first released by means of a cable 5 used for retracting the leg. The lock is shown in section, Fig. 5, a spring plunger 15 being carried in the arm 7 and having a nose 9 engaging in a cavity of the part 6 at the joint. Tension on the cable 5, acting on a pivoted lever 27 and a rod 26, which draws the nose 9. A compression spring 10 acting on a collar 22 sliding on the arm 7 is connected by tie-rods 24 to the arm 6 for urging the two arms 6, 7 towards their co-axial position is further compressed by the further action of the cable and lever 27 upon the collar 22 so that the spring 10 no longer acts upon the arm 6 since the connection between the rods 24 and the arm 6 is a pin-and-slot lost-motion one. The entrance of the nose 9 of the plungar 15 into the cavity in the arm 6 moves a spring-controlled plunger 35 to complete a signal-light circuit.