Stepper motors

Festo stepper motors

Stepper motors enable precise positioning operations, so they are used when high accuracy is required for demanding positioning tasks. They consist of a stationary stator and a rotor rotating within it, which is driven by torque generated by differently aligned magnetic fields in the stator and rotor. The rotor always rotates in such a way that the greatest possible magnetic flux is created. Stepper motors are primarily used in factory automation, but are also being used more and more in mechanical and plant engineering.

Advantages of stepper motors

Very high torque at a low rotational speed is characteristic of stepper motors. On the one hand, this enables a quick start, and on the other hand – thanks to the high holding torque – the ability to easily stop the application. The direction of rotation can also be changed quickly at any time. Other fundamental advantages of stepping motors are the high level of accuracy that is achieved with their use and the simple control of the respective rotor position. In addition, there are no brushes installed in stepper motors, which contributes significantly to the high mechanical durability of the application.

The different stepper motor types

There are basically three different types of stepper motors: the reluctance stepper motor, the permanent magnet stepper motor and the hybrid stepper motor. The latter combines the properties of reluctance and permanent magnet stepper motors and is therefore the most efficient of the three variants. Hybrid stepper motors have a stator with multi-toothed stator poles and a rotor consisting of up to 200 rotor teeth, which can move in step angles of 1.8° each. Hybrid stepper motors have a high static and dynamic torque and a very high stepping speed and are therefore used in numerous applications, including PC drives and printers. The main areas of application for hybrid stepper motors in industry are machine tools and handling machines.

Festo stepper motor EMMS-ST

Festo relies on hybrid technology in the further development and production of stepper motors. The EMMS-ST stepper motor is part of our core range and is ideally suited for simple positioning applications. EMMS-ST enables small increments with high driving torques, has optimized connection technology and is available in four sizes with flange dimensions of 28, 42, 57 and 87. It is also optionally available with a holding brake.

Stepper motor EMMS-ST