GB685588A - Engine starter gearing - Google Patents

Abstract

685,588. Turning-gear. BENDIX AVIATION CORPORATION. Nov. 15, 1950 [Nov. 18, 1949], No. 27967/50. Addition to 665,242. Class 7 (v). In an engine starter gearing comprising a pinion 2 slidably journalled upon a power shaft 1. for. movement into and out of mesh with a gear 3 of the engine to be started, a hollow sleeve 4 slidably but non-rotatably mounted on the power shaft 1, a driving coupling member 6 splined on the sleeve 4, a barrel 8 enclosing the driving member 6, a driven coupling member 18 journalled in the barrel 8, both coupling members 6 and 18 having co-operating inclined torque-transmitting surfaces 16 and 17, respectively, yielding means, for example, spring discs 13, holding the surfaces 16, 17 in driving engagement, the driven member 18 and pinion 2 having inclined teeth 19 and 21, respectively, forming an over-running clutch connection to the. p.inion and yielding means, such as a spring 22, urging. the over-running clutch into the closed position, there is both provided centrifugal means, for example, balls 29, for overcoming the spring 22 and for holding the over-running clutch disengaged when the pinion is rotating above a given speed, and means such as a manual or electromagnetically operated. shift fork 28 for moving the sleeve 4, barrel 8 and pinion assembly on the power shaft 1; the barrel may have a shoulder 12 forming an abutment for the driving member 6 which is held against the shoulder by the discs 13 and the pinion 2 may have .a swivel connection to the barrel comprising an inturned forward, end 9 that engages over a flange 11 of the pinion 2. The inclined surfaces 16, 17 .wedge the driven member 18 into engagement with the flange 11 upon torque being transmitted therethrough whilst the discs 13 yield to allow the surfaces 16, 17, to ratchet over each other upon the occurrence of an overload. When, the engine starts the acceleration of the pinion 2 causes the over-running clutch teeth 19, 21 to wedge themselves apart, the backward movement of the driven member 18 being permitted by the spaces between the inclined surfaces 16, 17. If the pinion 2 over-runs above a given speed the balls 29, located in passages 31 of the pinion hub, 32, move outwardly and force the. member 18 further to the left so completely separating teeth 19, 21. so that the pinion may freely over-run without wear and heating of the clutch parts.