Views: 0 Author: Site Editor Publish Time: 2025-03-05 Origin: Site
In high-precision fields such as automation equipment, medical instruments, and robotics, micro linear stepper motors have become the core components of drive systems due to their precise control, compact structure, and stable performance. However, facing the dazzling array of product models and technical parameters in the market, how to choose a micro linear stepper motor that suits one's own needs? This article will outline the key considerations and provide a systematic purchasing guide for you.
一、 Clear application requirements: The scenario determines the core parameters
Before selecting a motor, it is necessary to clearly define its application scenarios and target functions. There are significant differences in the load capacity, accuracy, speed, and environmental adaptability requirements of motors in different scenarios
The load capacity of micro linear stepper motors is usually expressed in terms of torque (unit: mNm) and thrust (unit: N). For example, a micro liquid pump in medical equipment may only require a few mNm of torque, while an automated robotic arm may require tens of N of thrust.
Operation suggestion: Calculate the maximum static friction force, inertial load, and acceleration requirements that the motor needs to overcome in practical applications, and reserve a safety margin of 20% -30%.
The step angle (such as 1.8 ° or 0.9 ° after subdivision) and repeat positioning accuracy directly affect the control effect. For example, the Z-axis movement of a 3D printer needs to achieve an accuracy of ± 0.01mm, while the focusing system of an optical instrument may require higher precision.
Solution: Choosing a motor that supports micro step subdivision drive (such as 256 subdivision) can significantly improve motion smoothness and positioning accuracy.
High speed applications, such as high-speed dispensing machines, require attention to the maximum speed (RPM) and acceleration performance of the motor. However, it should be noted that the torque of micro motors will decrease during high-speed operation, and the performance matching degree under actual working conditions needs to be evaluated through the "torque speed curve".
Permanent magnet stepper motor: Low cost, suitable for low torque scenarios, but high heat generation.
Hybrid stepper motor: combines high precision and high torque, suitable for precision instruments.
Linear stepper motor: directly converts rotational motion into linear motion, eliminating the need for transmission mechanisms, suitable for space constrained scenarios.
The diameter range of micro motors is usually between 10-42mm, and flange installation (NEMA standard) or customized fixing scheme should be selected according to the internal space of the equipment. For example, a 20mm diameter motor is suitable for driving endoscopes, while industrial sensors may require a flatter 12mm design.
Temperature: Industrial environments require the selection of high-temperature resistant models (working temperature -20 ℃ to+85 ℃).
Protection level: IP65 dustproof and waterproof motor is optional for food processing equipment; Vacuum environment requires special lubrication and sealing treatment.
Electromagnetic compatibility: Medical or laboratory equipment should have low electromagnetic interference (EMI) characteristics.
The performance of micro stepper motors is highly dependent on the supporting drive system. Attention should be paid to the following compatibility:
The output current of the driver needs to be consistent with the rated current of the motor. For example, if a motor with a rated current of 0.5A is paired with a 1A driver, it is necessary to set the current limit through dialing or software to avoid burning the coil.
Select pulse/direction control (commonly used in PLC) or bus communication (such as CANopen, EtherCAT) based on the interface of the upper computer, the latter being suitable for high-end devices with multi axis collaboration.
High subdivision mode (such as 32 subdivision) can reduce vibration noise, but it will increase the burden on the controller. Suggest balancing the subdivision level and system response speed through actual testing.
Provide detailed specifications, 3D model files, and installation guidelines.
Special applications such as aerospace or deep-sea equipment may require customized shaft length, outlet direction, or special materials such as titanium alloy shells.
Check the MTBF (mean time between failures) data of the motor. Industrial grade products typically require>10000 hours. Simultaneously confirm whether the warranty scope includes vulnerable parts such as rotor wear and tear.
After completing the preliminary selection, it is recommended to verify the compatibility through the following tests:
No load test: Observe whether the temperature rise of the motor at the target speed is normal (usually<70 ℃).
Load experiment: Gradually increase the load to the maximum design value and check for step loss or overheating.
Long term operation simulation: Run continuously for 24-48 hours to evaluate the trend of noise and vibration changes.
