Coaxial starter motor

摘要

A coaxial starter motor comprises an electric motor which produces a turning moment; a planetary gear mechanism for speed reduction, which transmits the rotation of the armature shaft of the motor in such a way that the angular speed of the output part of the mechanism is lower than that of the armature shaft, a one-way clutch which transmits the output torque of the planetary gear mechanism when engaged, a rotary output shaft, the rearward region of which forms the inner element of the clutch; a pinion which is arranged in such a way on the outer circumferential surface of the rotary output shaft that it meshes with the ring gear of the engine when the pinion receives the torque from the rotary output shaft; an electromagnetic switch which is provided around the pinion in order to move the pinion forwards and drive the engine; and a spring which is provided between an actuating element, which is moved forwards when the switch is excited, and the pinion in order to push the pinion forwards.