The PST.28 stepper motor offers an ideal balance of cost, compact size (28 mm ), and torque, making it a key actuator in commercial and premium home coffee machines. Its main roles include grind adjustment, dose metering, and nozzle/milk system positioning.

1. Applications

· Grind Adjustment: Low-speed, high-torque drive enables micron-level burr displacement. Open-loop stepping ensures precise switching from espresso to coarse grind, while holding torque prevents drift from vibration.

· Dose Control: Step-count control of dosing spoons or augers accurately meters bean volume, supporting multiple recipes (single/double espresso, American) without hardware changes.

· Positioning: Miniature motors adjust nozzle angle to avoid dripping and drive milk jugs along X/Y axes. With micro-stepping, basic latte art patterns are achievable.

2. Drive Optimization

· Micro-stepping (e.g., 1/32): Eliminates low-speed clogging and vibration, improving smoothness and resolution.

· Trapezoidal profiling: Reduces start/stop shock and noise for quiet operation.

· Closed-loop (optional): Encoder feedback compensates for missed steps, ensuring absolute reliability.

3. Conclusion

Stepper motors convert complex actions into repeatable digital commands, guaranteeing consistent coffee flavour. With 20+ years of motion control experience, Power Motor supports OEM and top suppliers.

We also welcome you to visit our company for an inspection and investigation before you need a customized motor project. Our engineers will also provide suitable solutions based on  your requirements.

Contact us for a customized motor solution!

�� Tel：400-666-3630, ✉ Email: info.power@power-motor.com

Note:‌ This article is contributed by Power Motor Sales Department