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Welcome to PCB Heaven techlabs.
Today i will show you how the brushless motors are made.
Before you see this video, make sure that you do know
how the simple DC motors with the brushes work.
If you don't, i strongly suggest that you follow the link that appears on your screen,
there is a video there that explains exactly how the brushed motors work
It's important to have this knowledge, as during this presentation i will assume that you do.
This is a 3D model of a brushless motor and you can see the rotor of the motor.
This is the base of the motor,
and usually, on the back side of the base there is a controller circuit.
The brushless motors have this major drawback that they need a controller circuit to operate.
There's usually one controller chip and a couple of FET transistors or something else
to control the power of the coils.
These two pins over here are for the power supply of the motor.
There are many types of brushless motors,
other with two pins, other with three pins, maybe with four pins...
But we will explain the simplest, with two pins.
Instead of taking one by one the parts out of the motor and explain them,
I will rather do it backwards, i like this method.
I will break completely the motor and start from the base,
and i will build it part by part.
This is a common base actually, and you can see the holes for the coil wires.
There are usually four coils so we need eight holes.
And in the middle there is this support piece. This is for the stator components.
And also there is a hole through all this piece,
and this is for the bearings and the shaft of the rotor
The four electromagnets are fixed inside these four hole around this central piece.
And in the middle front and back, there are pocket for the rotor bearings.
I will start mounting the motor from these bearings
I will put the first ball bearing in front
And there is another ball bearing on the back side.
The bearings are in position.
And not its time to complete the stator.
The stator is actually composed from the four electromagnets, also known as the armature.
They are fixed in a cross pattern, and unlike the normal brushed DC motors,
the armature in brushless motors is not moving and therefore it belongs to the stator.
And this is the complete armature.
I will need the four coils.
The coils are not winded in the same direction.
I mean that two coils that are near by, will never have the same polarity, the same magnetic polarity.
And therefore, either the windings are reversed, or the current that flows is reversed.
The stator is almost fixed now.
You can see the wires from the coils on the bottom side.
They go through the base.
And also you can see a rectangular hole here.
This rectangular hole is for the Hall sensor.
The Hall sensor is the component that makes the brushless DC motors possible to operate.
If you want more information about the operation of the brushless motors
you'd better follow the link in the info of this video.
Just click the "Show more" on the bottom side :D of this video,
and follow the link that you can find in there.
Let's put the Hall sensor in position.
It goes... There... This is the Hall sensor.
As you notice, it is between two armatures,
and actually, the geometric position of the Hall sensor is very critical
It must be exactly in the middle of the two armatures.
Now i put the controller PCB on the back side.
This is the controller PCB...
The stator is not 100% completed.
For the rotor... The rotor in a brushless motor is fairly simple.
Actually the rotor carries only four permanent magnets...
These four permanent magnets.
And unlike the brushed DC motors, that have two magnets actually,
they are places in a North-South- North-South pattern.
And the magnets along with the cover of the rotor, they move around the stator.
This is the great difference from the brushed motors.
The brushless motors do not have any coil on the rotor,
and they don't need any power to the rotor,
so, they don't have brushes.
That's why they are called "brushless".
And that's the whole idea behind them.
The lack of brushes means of course great increase in lifetime,
because the brushes are as you know something that wears off very fast.
And that's why they are used extensively in applications that they need reliability.
Now to complete the motor.
I will place the shaft, here, the shaft goes here, this is the shaft.
And on the shaft, the cover of the rotor is placed.
Now this actually... The motor is now completed.
The permanent magnets are as you understand glued on the inside perimeter of the rotor cover.
I would make it transparent so that you see how it rotates.
Okay...
Thank you for watching this video,
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