Starter for internal combustion engines

摘要

A compact starter for internal combustion engines wherein the armature shaft of an electric motor rotates an axially movable pinion through the medium of an overrunning clutch which allows the pinion to rotate relative to the shaft when the pinion meshes with a gear of the engine and the gear is rotated by the engine upon completion of the starting operation. A shifting sleeve for the pinion has steep internal threads meshing with complementary external threads of the shaft and is connected to the clutch and pinion so that the pinion moves with the sleeve toward engagement with the gear of the internal combustion engine when the sleeve is held against rotation with the shaft by a brake whose parts are mounted on and surround the sleeve. The brake operates between a flange of the sleeve and a blocking cylinder which is rotatably mounted on but normally rotates with the sleeve by way of the brake. An electromagnet is energizable in response to starting of the motor to move a pin into engagement with one of several external teeth on the blocking cylinder whereby the brake holds the sleeve against rotation and the sleeve moves axially of the rotating shaft to engage the pinion with the gear. When the electromagnet is deenergized, a return spring is free to move the sleeve axially in a direction to disengage the pinion from the gear.