What do motors do

The commutator is simply a pair of plates attached to the axle. These plates provide the two connections for the coil of the electromagnet. The "flipping the electric field" part of an electric motor is accomplished by two parts: the commutator and the brushes. The diagram shows how the commutator in green and brushes in red work together to let current flow to the electromagnet, and also to flip the direction that the electrons are flowing at just the right moment.

The contacts of the commutator are attached to the axle of the electromagnet, so they spin with the magnet.

The brushes are just two pieces of springy metal or carbon that make contact with the contacts of the commutator. The key is that as the rotor passes through the horizontal position, the poles of the electromagnet flip. Because of the flip, the north pole of the electromagnet is always above the axle so it can repel the stator's north pole and attract the stator's south pole. Usually the rotor will have three poles rather than the two poles as shown in this article.

There are two good reasons for a motor to have three poles:. It is possible to have any number of poles, depending on the size of the motor and what it needs to do.

Now, we're going to look at the AC motor. AC motors use alternating current instead of direct current. It shares many parts with a DC motor, and it still relies on electromagnetism and flipping magnetic fields to generate mechanical power.

The winding of the stator in an AC motor kind of does the job of the rotor of a DC motor. In this case, it's a ring of electromagnets that are paired up and energized in sequence, which creates the rotating magnetic field. You'll remember that the rotor in a DC motor is hooked up to the battery. But the rotor in an AC motor does not have any direct connection to a power source. Nor does it have brushes. Instead, it often uses something called a squirrel cage.

You read that right. The squirrel cage in an AC motor is a set of rotor bars connected to two rings, one at either end. It's kind of like something a caged mouse or squirrel would run inside. The squirrel cage rotor goes inside the stator. When AC power is sent through the stator, it creates an electromagnetic field. The bars in the squirrel cage rotor are conductors, so they respond to the flipping of the stator's poles.

That's how the rotor rotates, which creates its own magnetic field. The key to an AC induction motor, where the field of the rotor is induced by the field of the stator, is that the rotor is always trying to catch up. It's always looking for stasis, so it's rotating to find that steady state. But the electromagnetic field produced by the stator using AC power is always going to be a little faster than the rotor's field.

The spin of the rotor is creating the torque needed to create mechanical power to turn the wheels of a car or the whirr of a fan. Some AC motors use a wound rotor, which is wrapped with wire instead of being a squirrel cage. The squirrel cage kind is more common, though. Since the industrial technology level in Japan in those days was quite lower than that in Europe and America, most of electric devices were imports. However, it is said that they frequently became out of order. So, domestically produced motors gathered momentum gradually.

In , the first motor induction motor produced in Japan launched. Then, in , Yaskawa Electric was established as a company which manufactured and sold electric products purely produced in Japan and launched the first order of induction motor in There are various ways to call motors depending on the categorization of functions and structures such as a servo motor for its precise work toward commands, a linear motor for its linear movement, a vibrating motor for its vibration to notify incoming call on mobile phone and a geared motor for combined speed reducer.

Motors also have a few names although their structures are the same. For example, the list below shows a few names used in motors for EV. People named motors to define the differences from others, resulted in leaving with many names for motors.

A brushless DC electric motor is a DC motor which replaced its brush and commutator with semiconductor switching element. A universal motor is able to rotate the motor in high speed with AC V electricity for households while holding the same brush and commutator for DC motors. Other than these, there are a stepping motor that moves with square-wave current flow and a switched reluctance motor. An ultrasonic motor is a special motor that works by vibrating piezoelectric ceramic with applying high frequency voltage.

The motor which many Japanese pupils used in their science experiments when they were in primary schools was DC motors.

It is the most popular motor used in models, consumer electronics and vibration motors in mobile phone. To explain roughly about the structure of motors, there are rotor and stator in it. Rotor is a part connected to shaft, and stator is a fixed part which comprises the exterior.

The stator in DC motors holds permanent magnets and brushes that supply electric current to the rotor, and the rotor holds windings and a commutator. Once the brushes supply DC current to the commutator, electric current starts to flow through the windings connected to the commutator and generates torque. Sometimes the best way to understand how a motor works is to build one yourself. You can build a simple DC motor with common household items.

By sending current through a carefully shaped wire in the presence of a magnetic field, we can create a portion of our circuit that will rotate, allowing us to convert electric energy into mechanical energy. Make a coil of wire by wrapping winding wire around a "D" cell 1. Leave about 2 to 3 cm sticking out from both ends. Make sure that all of the turns are wound in the same direction.

The coil should be well balanced on these ends so that it will turn easily when placed in the cradle provided by the paper clips. You should hold the coil together by twisting the last loop around the coils to wrap the coils together. When the coil is in the position shown, one of the wire ends, which will contact the paper clips, should have the insulation removed on the bottom side only. The other end should be completely stripped where it contacts the paperclip.

This way, current will flow through the coil about half of the time. Try to start your motor by giving the coil a small spin. Try, adjust, try, adjust, try and adjust again until you succeed! If the coil is oriented as shown in the image, current is passing clockwise through the coil and the magnetic field points upward, then the top of the coil will feel a force pointing out relative to the computer screen you are viewing this on , and the bottom of the coil will feel a force pointing in.

This effect can be used to make an electric motor. The diagram shows a simple motor using direct current dc. Starting from the position shown in the diagram of the dc motor :.