Starter for engine

A starter comprising:

• a motor that has an armature with a commutator disposed in an end of an armature shaft and generates torque in the armature;
• a speed reducer that reduces a rotating speed of the motor and increases drive torque, the speed reducer being disposed in the motor opposite to the commutator;
• a pinion that transmits the drive torque increased by the speed reducer to an engine ring gear;
• a partition wall that is disposed between the motor and the speed reducer to separate the motor and the speed reducer, the partition wall having a hole formed in a central part for passing through the end of the armature shaft;
• a pinion driving solenoid that forms a first electromagnet by energization, and pushes out the pinion to the ring gear side by using an attraction power of the first electromagnet;
• and
• a motor energizing switch that has a second solenoid that forms a second electromagnet by energization, and opens and closes an electric point of contact interlocking with an ON/OFF operation of the second solenoid for intermitting a current flowing into the motor, wherein
• the starter is able to control independently operation of the pinion driving solenoid and operation of the motor energizing switch separately,
• the starter further comprising a rotation detector that outputs a rotation signal of a frequency proportional to the rotating speed of the motor, and
• the rotation detector is disposed in a motor side inner space where the armature is disposed separated by the partition wall.