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Stepper Motors

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Basic Structure and Operating Principle of Stepper Motors_Segment_0_xvid.avi

Click once to show video

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HOW CAN WE INCREASE THE RESOLUTION, OR STEPS, OF A MOTOR?

1. Increase the number of stationary electro magnets in the outer stator

2. Increase the number of poles in the rotating rotor

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Example: Six pole rotor, four electro magnets.

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STEPPER MOTOR OPERATIONHow to make the rotor spin

Rotor

Stator coils

CNC Stepping Motor

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The top electromagnet (1) is turned on, attracting the nearest teeth of a gear-shaped iron rotor. With the teeth aligned to electromagnet 1, they will be slightly offset from electromagnet 2

The top electromagnet (1) is turned off, and the right electromagnet (2) is energized, pulling the nearest teeth slightly to the right. This results in a rotation of 3.6° in this example.

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The bottom electromagnet (3) is energized while electromagnet (2) is turned off; another 3.6° rotation occurs.

The left electromagnet (4) is energized, rotating another 3.6°. When the top electromagnet (1) is again enabled, the teeth in the sprocket will have rotated by one tooth position; since each step is 3.6° it will take 100 steps to make a full rotation in this example.

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HOW CAN WE INCREASE THE SPEED THE MOTOR ROTATES AT?

1. Increase the rate at which we switch the magnets on and off

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THE END