With regard to power tools. I’ve Googled and read, and it only seems to confuse me more. Thank you.
In: Engineering
So imagine the rotor (the central portion of the motor) thats rotating inside the stator (the outer casing). There is power that needs to be given to the rotor in the form of electricity. This electricity runs through some copper coils and creates a magnetic flux (at multiple circumferential locations or coils placed around the rotor) . The magnetic flux created in the rotor interacts (attracts / repels) with the corresponding magnetic flux created by the permanant magnets mounted on the stator inside surface. This is how the rotor (hence the shaft) rotates.
Now remember – that power is being supplied to a rotating part. How to ensure that electricity wires are connected continuously to the rotating part? This is done by brushes (which are actually nothing like brushes but are rather solid blocks of low friction and low resistance material – normally some form of carbon or graphite). So the brushes are stationary – fixed – and the rotor is in constant contact with the brushes getting the power to create its magnetic flux (through specially designed terminals, called commutator, corresponding with each magnetic flux location)
Now there is a matter related to positive / line and negative / neutral of the electricity – but that discussion may need some images to explain.
Brushless motors on the other hand use electronics to keep shifting the power to different magnetic flux locations / coils on the rotor creating a rotating magnetic flux (not in the rotor but in the stator).
Hope that helps…
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