Patent ID: 6633099
Filing Date: 2003-10-14
Classification: H02K,Y10T

Abstract:
A coaxial starter motor assembly comprising:a housing; an electrical motor provided in the housing having a rotatable armature shaft; a rotatable drive shaft engageably linked with the armature shaft; a pinion assembly provided in the housing engageable at one end with the drive shaft and including a pinion at the other end engageable with a flywheel of an engine; a solenoid assembly provided in the housing for selectively energizing the electrical motor, wherein the solenoid assembly is coaxial with the drive shaft, the solenoid assembly including a plunger having a bore, the plunger being engageable with the pinion assembly to move the pinion assembly including the pinion into engagement with the flywheel, and the plunger being engageable with a moveable contact to move the moveable contact to electrically connect with a pair of fixed contacts; a return spring positioned at least in part within the bore of the plunger of the solenoid assembly for moving the pinion assembly including the pinion away from engagement with the flywheel, wherein the return spring is spaced from the pinion assembly; wherein energization of the solenoid assembly moves the plunger to move the pinion assembly to engage the pinion with the flywheel; wherein upon deenergization of the solenoid assembly, the return spring moves the pinion assembly to move the pinion from engagement with the flywheel; and wherein upon deenergization of the solenoid assembly, the plunger is capable of moving independently of the pinion assembly to thereby break the electrical connection between the moveable contact and the fixed contacts before the return spring moves the pinion assembly to move the pinion away from engagement with the flywheel.