A stepper motor is an electromechanical device that converts electrical pulses into precise mechanical motion. It is designed to move in discrete steps, hence the name "stepper" motor. Unlike conventional motors that rotate continuously, stepper motors rotate incrementally, typically in steps of 1.8 degrees (for a motor with 200 steps per revolution).
The basic construction of a stepper motor consists of multiple toothed electromagnets arranged around a central rotor. The rotor is typically made up of a permanent magnet or a soft magnetic material. The number of teeth on the rotor is usually a multiple of the number of electromagnets surrounding it.
Stepper motors require a specialized driver circuit to control their motion. This driver circuit delivers precise sequences of electrical pulses to the motor windings, which in turn produce the rotational movement.
The most common types of stepper motors are bipolar and unipolar motors:
1. Bipolar Stepper Motor: A bipolar stepper motor has two windings or phases, and each phase can be controlled independently. The windings have a center tap, and the motor can have either four or eight leads. Bipolar motors provide more torque compared to unipolar motors but require more complex driver circuits.
2. Unipolar Stepper Motor: A unipolar stepper motor has multiple windings with a center tap for each phase. The windings are typically energized in a specific sequence to create the steps. Unipolar motors are easier to control but generally provide less torque than bipolar motors.
To rotate the stepper motor, the driver circuit applies voltage or current to the motor windings in a specific sequence. The most common sequence is known as "wave drive" or "one-phase on." In this mode, the driver energizes one phase at a time and steps through the phases in a cyclic manner to rotate the motor.
More advanced driving techniques, such as "full step," "half-step," or "microstepping," can be used to achieve smoother motion or finer positioning. These techniques involve different energization patterns for the motor windings, which divide a full step into smaller increments.
Keli motor as one of the largest micro motor R&D, manufacturers, and exporters in China,we mainly supply shaded pole motor, stepper motor, DC brushless motor,etc.
Shaded pole motors are a type of single-phase induction motor. Unlike other types of single-phase induction motors, shaded pole motors don't use a start capacitor or a start winding to kickstart rotation. Instead, they rely on a simple design that creates a rotating magnetic field.
The rotor of a shaded pole motor is made of a solid metal cylinder or a stack of metal laminations. The rotor typically has a unique design where a portion of it is surrounded by a copper or aluminum shading coil. This coil is responsible for creating the shaded pole effect, which induces a phase shift in the magnetic field and creates the starting torque needed for the motor to begin rotating.
The materials used in the rotor of a shaded pole motor are typically low-cost metals like aluminum or steel. These materials provide the necessary magnetic properties and mechanical strength required for the motor to operate efficiently. The rotor may also be coated or treated to prevent corrosion and improve its longevity.
Overall, the rotor structure and materials of a shaded pole motor are designed to be simple, cost-effective, and reliable for applications where low starting torque and continuous operation are required, such as in small fans, appliances, and some HVAC systems.
Established in 1992, Keli motor has become one of the largest micro motor R&D, manufacturers, and exporters in China, its No. 1 sales and production of shaded pole motors. In addition to shaded pole motors, we also produce and sell stepper motor, universal motor, BLDC motor, etc.