GB558120A - Improvement in engine starter gearing - Google Patents

Abstract

558,120. Turning gear. BENDIX AVIATION CORPORATION. June 17, 1942, No. 8319. Convention date, June 21, 1941. [Class 7 (v)] In an engine starter comprising a pinion 2 slidably journalled on a power shaft 1 and actuated by means including inter-threaded members 8, 21 to engage and drive an engine gear 3, and centrifugal means 34 for holding the pinion in mesh with the gear 3, the threads of the members 8, 21 are formed to disengage and allow the pinion to overrun the power shaft while maintaining its engagement with the gear 3. As shown, the member 8 is a screwed sleeve slidable on a reduced portion 9 of a sleeve 4 pinned to the shaft 1 ; the sleeve 8 normally abuts a stop nut 11 on the sleeve 4 and is driven through a spring 17 connecting heads 6, 14 on the sleeves 4, 8. The head 14 is in splined connection with tongues 13 on the end of the sleeve 8. The nut 21 threaded on the sleeve 8 has lugs 22 engaging slots 23 in a barrel 24 fixed at 25 to the pinion 2. A spring 26 normally holds the nut 21 at the forward end of the slots 23 and is retained by a flanged ring 27 having projections 29 extending into the slots 23 and retained by a split ring 31. In operation, rotation of the shaft 1 and sleeves 4, 8 causes axial movement of the nut 21 and barrel 24 to engage the pinion 2 with the gear 3, the sleeve 8 then being threaded to the left to compress the spring 17. When the engine fires and the gear 3 overruns the pinion 2, the sleeve 8 returns against the stop 11, and the nut 21 is threaded back on the sleeve 8 until the latch 34 engages the stop 11 ; the nut is then free to run off the threads of the sleeve, while the pinion is retained in mesh until the speed is sufficient to disengage the latch 34 by centrifugal action.