GB614201A - Improvements in engine starting devices - Google Patents

Abstract

614,201. Turning-gear. BENDIX AVIATION CORPORATION. July 5, 1946, No. 20211. Convention date, Aug. 2, 1945. [Class 7 (v)] The engine starter drive described in Specification 566,399 has modified latching means for preventing disengagement of the pinion from the engine gear, said means comprising a barrel member secured to the nut by which the pinion is operated. The starting motor SM has an armature shaft 1 on which is journalled the sliding pinion 6 engageable with an engine gear 7. A sleeve 3 is pinned to shaft 1 and a screw-shaft 8 loose on the sleeve is driven therefrom through a spring 11. The screw coacts with a nut 12 secured to a barrel 13 and connected to the pinion through an overrunning toothed clutch 17, 19, the members of which are normally separated by a spring 25. In order to restrain initial rotation of the pinion to ensure prompt engagement, a detent 26 is connected to the plunger of the starter switch 27 and is projected into frictional engagement with the barrel, Fig. 1, when the switch is operated by closing the usual manual switch 33. The barrel and pinion are thus moved forward and when the pinion engages the stop 39 the clutch 17, 19 is engaged and torque is transmitted to the pinion. In this position the detent engages behind a shoulder 15 on the barrel, thus preventing premature demesh of the pinion. The detent is located to allow the barrel to move back sufficiently to disengage the clutch teeth when the engine fires. If the engine threatens to stall, the operator keeps switch 33 closed, preventing demesh of the pinion and causing cranking to be resumed when the engine speed falls sufficiently. When the engine runs on the switch 33 is released and the torque transmitted through the spring 25 causes return of the pinion to the Fig. 1 position. In a modification, Fig. 3, the switch plunger 27 acts through a flexible spring member 41 which has a bent-over end 43 adapted to engage behind the barrel 13 and prevent withdrawal of the pinion. In a modification of this form, the spring member 41 carries a block of non-metallic material to prevent wear.