What is starter motor ??and comparison

starter motor

1. The starter motor is used to start the engines, because the engine cannot run itself at first.

2. The starter motor is connected to the flywheel 112 teeth and the motor pinion has 8 teeth.

3. The pinion turn 14 times for every turn of the flywheel, in other words the torque from motor is multiplied by 14 times.

Here  question arises that how a huge fly flywheel driven by a small pinion ???

For this purpose planetary gear use inside the starter motor.

Planetary gears.

1. Planetary gears, which can supply a lot of speed reduction and torque in a small package, have operating characteristics beyond those of fixed-axis gear trains.

2. Planetary gear ratio 6:1, so the six rotation of our motor gives us one rotation of a carrier, so the gear box reduces the speed by six times.

Spinning our motor 84 times will turn the engine once.

Starter motor voltage comparison with compressor motor.

In hot days 200amps, but in cold days with thick oil it might take 400amps

, Normally its portably 100amps, may be 200amps.so this motor compare to beefy mains powered compressor motor. We can’t compare the current figure 400apms, because a low voltage like 12 volts require much more current then higher voltage like the 240volts that motor takes. So voltage is 12 and the current is 400amps. So the 400 times 12 gives us 48watts or 4.8kwatts. A kettle takes about 1.2kw, so this starter can put out the power of four kettle and this huge motor takes 2.2kw, so starter motor is double the power of this bigger one.

Design.

Bigger motor covered with cooling fins because it get hot and it run hours or more then that, and starter motor is without cooling fins because it run for second. 

Published by Science Tube 08 September 2020