Magnetic brake system for starter motor

摘要

An engine starter system is disclosed. The starter system includes an electric cranking motor having a shaft and configured to crank the engine. The starter system further includes a planetary-type reduction gear unit that has a starter motor ring gear. The starter system has a pinion mechanism mounted on the shaft and configured to selectively engage a ring gear of the engine. A clutch assembly is configured to transmit torque between the shaft and the pinion mechanism. The clutch assembly includes a current conducting material and the starter motor ring gear includes one or more permanent magnets. The starter system employs the principle of Lenz's law to reduce the overrunning rotational speed of the cranking motor upon disengagement of the pinion mechanism from the engine's ring gear after the engine has started.