A stepper motor is a brushless DC electric motor. It lots a full rotation into separate equal steps. The position of the motor can then be directed to move and keep one of the steps without any open-loop controller; meanwhile the motor is cautiously sized to the application.
Main principals of operation
DC brush motor rotates for some period of time when voltage is used in its terminal. Stepper motor, on the contrary, has multiple "toothed" electromagnets that are placed around a central gear-shaped iron. A microcontroller, an outside control circuit, energizes electromagnets. Thus, in order to make the shaft rotate, firstly, only one electromagnet is energized; this makes the teeth of the gear magnetically sticked to the teeth of the electromagnet. When the gear's teeth approach the first electromagnet, they moves to another electromagnet. So when the primary electromagnet is turned off and the next one is turned on, the gear rotates somewhat to straighten with another one, therefore the process reoccurs. Each of the above described rotations is known as a "step", with a number of steps achieving a full rotation. In such a maner, the motor can be turned by an accurate angle.
DC brush motor rotates for some period of time when voltage is used in its terminal. Stepper motor, on the contrary, has multiple "toothed" electromagnets that are placed around a central gear-shaped iron. A microcontroller, an outside control circuit, energizes electromagnets. Thus, in order to make the shaft rotate, firstly, only one electromagnet is energized; this makes the teeth of the gear magnetically sticked to the teeth of the electromagnet. When the gear's teeth approach the first electromagnet, they moves to another electromagnet. So when the primary electromagnet is turned off and the next one is turned on, the gear rotates somewhat to straighten with another one, therefore the process reoccurs. Each of the above described rotations is known as a "step", with a number of steps achieving a full rotation. In such a maner, the motor can be turned by an accurate angle.
Types
Here are stepper motors of four major kinds:
- Permanent magnet stepper ( it can be divided into 'hybrid' and 'tin-can'; tin-can is a cheaper one, and hybrid with smaller step angle, higher power density and quality bearings)
- Hybrid synchronous stepper
- Lavet type stepper motor
- Variable reluctance stepper
Permanent magnet motor uses a rotor permanent magnet and is based on the attraction between the permanent magnet of the rotor and the electromagnets of the stator. Variable reluctance motor has a plain iron rotor and is based on the principle that minimum resistance is attained with minimum gap, that is why the points of the rotor are sticked towards the magnet poles of the stator. Hybrid stepper motors are called so as they present a combination of variable reluctance and permanent magnet approaches to acquire maximum power in a small cover size.
Two-phase stepper motor
There are two typical windings for the electromagnetic coils in a two-phase stepper motor: monopolar and bipolar.
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Alfa inc. brings forward wide assortment: stepper motor repair, bipolar stepper motor, dc stepper motor, stepper motor controller kit, types of electric motors etc. We are going to provide guarantee and support demand for merchandised goods. So as to score success we strive for satisfying the requirements of our customer. Our company is ready for cooperation with new business partners.