GB658445A - Starter apparatus for internal combustion engines - Google Patents

Abstract

658,445. Turning-gear. GENERAL MOTORS CORPORATION. May 11, 1949, Nos. 12507, 12508 and 12509. Convention dates, May 20, 1948, May 20, 1948 and Oct. 28, 1948. [Class 7(v)] In starter apparatus for internal-combustion engines comprising an electric motor having a shaft 32, a screw shaft 41 supported by the motor shaft 32 and driven thereby, a pinion 100 supported by the motor shaft for axial movement into mesh with the gear 106 of the engine to be started, a nut 51 threadedly engaging the screw shaft 41, a sleeve 83 which is moved axially by the nut and has an axial lost motion connection with the pinion by virtue of a longitudinal spline, a spring 102 for transmitting motion from the sleeve 83 to the pinion 100 in a direction to move the pinion towards the gear 106 and a clutch spring 90, which may be enclosed by a barrel 92, having its end turns normally in frictional engagement with the nut and sleeve in response to a rotative movement of the nut 51 relative to the sleeve 83 in the engine starting direction of rotary movement of the pinion, two abutments are provided consisting of a washer 111 on the motor shaft 32 and the end surface of the pinion 100, which abutments are adapted to contact when the pinion is fully meshed with the engine gear 106 so that the screw and nut rotate together as a unit. In operation, the pinion 100 is advanced into mesh with gear 106 in which position the abutments engage, the nut 51 continuing to move rightwardly until the inner end of the pinion 100 contacts a flange 84 on sleeve 83. The nut and screw shaft then turn together and the spring 90 wraps itself around the nut 51 and sleeve 83 until it transmits sufficient torque to crank the engine. When the engine starts the pinion and nut assembly are thrown back to the rest position and the spring 90 slips to dissipate some of the energy of the rotating parts. If tooth abutment occurs the nut 51 continues to rotate until sufficient torque is transmitted through the spring 90 to partially rotate the pinion 100 to index it whereupon the spring 102 moves it into mesh with the flywheel. In a modification, a stop nut and washer are located on the outer end of the screw shaft, the nut and screw shaft rotating together when the nut abuts the stop washer, which action occurs before the abutment of the pinion and flange 34 as in the Fig. 1 embodiment. In a further modification, a centrifugally operated latch is located on the nut so that the pinion is not demeshed in the event of a false start.