Types of Stepper Motors Used in Industrial Machines


In today’s industrial world, precision and accuracy are crucial requirements. Modern machines must be able to operate at high precision and accuracy for efficient and effective production. This is where stepper motors come in – a type of electric motor that can precisely control the movement of the machine. They are widely used in industrial machines due to their ability to provide accurate and repeatable motion control.

There are different types of stepper motors available in the market, each with their unique characteristics, suited for various industrial applications. In this article, we will discuss the four main types of stepper motors used in industrial machines, along with their features and practical examples.

1. Permanent Magnet (PM) Stepper Motors:
The first type of stepper motor used in industrial machines is the Permanent Magnet (PM) stepper motor. As the name suggests, they have a permanent magnet rotor, and the stator is equipped with multiple salient poles. These motors operate with a variable reluctance principle and have a step angle of 1.8 degrees.

One of the practical examples where PM stepper motors are used is in robotic arms. The precise and controlled motion of PM stepper motors allows robots to perform repetitive tasks with high precision. They are also used in CNC machines for controlling the movement of the cutting tools.

2. Variable Reluctance (VR) Stepper Motors:
Variable Reluctance (VR) stepper motors are similar to PM stepper motors, except they have a different stator and rotor construction. The rotor is designed with multiple teeth, and the stator has corresponding teeth aligned with the rotor. When energized, the rotor teeth align with the stator’s teeth, making them rotate. These motors have a step angle of 1.8 or 3.6 degrees.

A practical example of the industrial use of VR stepper motors is in the textile industry. They are used in spinning machines to control the speed and movement of yarns during the spinning process. The precise control provided by VR stepper motors ensures uniform and high-quality yarn production.

3. Hybrid Stepper Motors:
Hybrid stepper motors combine the best features of both PM and VR stepper motors. They have a permanent magnet rotor with multiple rotor poles and a stator with multiple phases. Hybrid stepper motors have a smaller step angle, ranging from 0.9 to 1.8 degrees, making them ideal for applications requiring high precision.

A widely used application of hybrid stepper motors in industrial machines is in 3D printing. The intricate and precise movements required in 3D printing are achieved through the controlled motion of hybrid stepper motors. They are also used in robotic welders, allowing for precise and repeatable movements in welding applications.

4. Linear Stepper Motors:
Unlike the traditional rotary motion of stepper motors, linear stepper motors produce linear motion along a track. They have a stator with multiple phases and a rotor with permanent magnets. Linear stepper motors are used in applications where linear motion is required, such as linear actuators in packaging machines and conveyor systems.

Another practical example of the use of linear stepper motors is in medical imaging equipment. They are used in MRI and CT scanners for precise and controlled movement of the scanning components, providing accurate and detailed images.

In conclusion, stepper motors are an integral part of modern industrial machines, ensuring the precision and accuracy required for efficient production. The type of stepper motor used in a particular application depends on the specific requirements of the machine. Each type of stepper motor offers unique features and benefits, making them suitable for various industrial applications. As technology advances, we can expect to see further developments in the design and application of stepper motors, making them even more essential in the industrial world.