Humanoid robots represent cutting-edge high-end intelligent manufacturing. Harmonic gears, RV gears and precision planetary gears inside their joints are core components that enable flexible movement and precise positioning. These gears feature small modules and intricate tooth profiles. Many thin flex splines and cycloidal wheels have extremely thin wall thickness, with narrow spaces at tooth roots, tooth grooves and meshing gaps. They impose highly stringent requirements on cleanliness, dimensional stability and surface integrity. After grinding, lapping, polishing and other machining processes, the parts are contaminated with cutting oil, lapping compound, fine metal powder and polishing debris. These micron-sized contaminants hide in blind spots between teeth, which can hardly be thoroughly removed by conventional soaking or spraying cleaning. If residues remain on gear meshing surfaces, increased friction, abnormal noise, transmission jamming and positioning errors will occur during joint operation. In severe cases, it will lead to premature wear and failure of reducers, undermining the motion accuracy and service life of humanoid robots. Therefore, the gear cleaning process has become an indispensable critical procedure in the manufacturing of humanoid robot joints.

SINOBARK focuses on the cleaning of precision transmission parts. We have developed dedicated ultrasonic cleaning equipment tailored to the structural characteristics and cleanliness standards of gears for humanoid robot joints. Based on the principle of ultrasonic cavitation, the equipment continuously generates countless tiny cavitation bubbles in the cleaning liquid. The periodic formation and collapse of bubbles produce high-density micro-impact flows that penetrate hard-to-reach areas such as tooth roots, tooth gaps and micro clearances. Without scratching precision tooth surfaces, altering gear geometric tolerances or damaging ultra-thin flex splines, the equipment removes oil stains, lapping residues and fine metal debris to meet the micron-level high cleanliness requirements for humanoid robot gears.

The fully automatic closed-loop equipment integrates ultrasonic cleaning, multi-stage rinsing, air knife dewatering and hot-air drying. Workpieces are conveyed automatically after clamping, minimizing manual intervention throughout the process. Parameters including ultrasonic power, cleaning duration and solution temperature can be finely adjusted to suit various joint gears of humanoid robots, such as flex splines and circular splines of harmonic reducers, RV cycloidal gears and small planetary gears. It supports mass production of workpieces with different materials and specifications. Consistent cleaning results greatly reduce quality instability caused by manual cleaning and adapt to the continuous production rhythm of robot component production lines.

Humanoid robots demand outstanding stability, durability and control accuracy for joints, and gear cleanliness directly determines the overall performance of reducers. Different from general cleaning machines, SINOBARK ultrasonic cleaning equipment balances cleaning power and workpiece protection, avoiding risks such as collision scratches and micro-deformation of tooth surfaces. Residual oil and debris indicators of cleaned parts stay stably within specifications, effectively lowering the early failure rate after joint assembly and ensuring smooth and precise robot movements including walking, grasping and posture adjustment.

Benefiting from years of technical accumulation in industrial ultrasonic cleaning, SINOBARK can provide customized solutions including standalone units, multi-tank linked systems and in-line automatic cleaning, matching the production line layout, capacity demand and cleanliness class of humanoid robot components. With stable, efficient and controllable ultrasonic cleaning technology, we resolve the cleaning challenges of precision gears for humanoid robots, lay a solid foundation for high-quality mass production of robot joint reducers, and facilitate the high-quality development of the high-end humanoid robot industry chain.