Motors

     An electrical motor converts electrical energy into mechanical energy. It uses a magnetic field to generate force.

     A motor has three main parts. The first is the rotor. This is the part of a motor that spins. It is usually wrapped with many coils so that when electricity passes through it, it makes a magnet. The rotor spins in the magnetic field created by the stator.

The stator is the part of the motor which creates a magnetic field that spins the rotor. It usually surrounds the rotor entirely, creating a strong field. It too is usually wrapped with coils of wire to make a magnet when electricity passes through it.

The final part which makes a motor work is the commutator. This is the piece which makes sure the rotor spins. When the brushes of electricity touch the conducting sides, the magnet turns on, and the rotor spins. However when it spins, the brushes move to where there is no conductor, and the rotor keeps freely spinning. This cycle happens over and over again very quickly, making the motor turn full revolutions.

My Motor

     For my motor, the construction is very simple:

First, I constructed my stator.

My stator consisted of five layers of single strand 14 gauge copper wire wrapped around two L-brackets made of galvanized steel. I also put a layer of duct tape in between each layer so that the layers wouldn't mix and mess up the field. Next, I made my rotor.

The rotor is made around a thin iron rod which spins. The rotor is wrapped with two layers of 24 gauge magnet wire, and secured in place above the stator. The magnets will power on, and the rotor will spin.

Finally, I built the commutator. The commutator is quite simple. The ends of the magnet wire from the rotor come to the commutator, and each end touches a different piece of copper taped over a cork. Both pieces of copper have a space between them on either side, allowing the electricity to easily turn on and off. This constant turning on and off causes the motor to spin 360 degrees.

This is the finished product:

Also, I attached a spool of thread near the back of the commutator to pull a toy car. I found a large space and tested how powerfully the motor can pull the car:

 

Problems with my Motor

     Most of the building process was quick, and easily done. However there are a few problems I encounter even now:

1) Inconsistency

     My biggest problem is inconsistency. Due to the way that the brushes are done, the speed of the motor is very inconsistent. Often the commutator pushes and bends the brushes out of the way, blocking the contact between the two. This can severely change the power of the motor and how fast it spins, making the difference between a C- and an A+.

                 

2) Winding the spool

     Often when the toy car is being wound, the thread will wind itself off the spool and into the way of the brushes. This could be a serious problem if it tangles with anything important.