THK’s DIR SERIES Ball Screw with Rotary Nut represents a sophisticated evolution in linear motion technology, engineered specifically for applications requiring high-speed rotation and precise axial movement. This innovative design features a rotating nut configuration where the nut itself rotates while the screw shaft remains stationary, enabling exceptional rotational speeds up to 10,000 rpm while maintaining precise linear positioning accuracy within ±0.01mm. The series incorporates THK’s proprietary precision-ground screw shafts with optimized groove profiles and high-grade bearing steel construction, ensuring minimal friction and extended service life even under continuous high-load conditions.

Key technical features include the integration of preloaded double-nut assemblies that eliminate axial backlash, critical for applications demanding high positional repeatability. The rotary nut design incorporates precision angular contact ball bearings directly into the nut housing, allowing for direct motor coupling without additional support bearings. This compact configuration reduces overall system length by up to 30% compared to conventional ball screw arrangements. Advanced sealing systems with multi-lip seals and grease retention features provide IP65-level protection against contaminants while maintaining optimal lubrication. The series offers multiple accuracy grades (C3 to C7) and various screw diameters from 16mm to 50mm to accommodate different load capacities ranging from 15kN to 180kN.

Performance advantages stem from the unique rotating nut architecture, which enables significantly higher rotational velocities than traditional designs while minimizing vibration and heat generation. The direct drive configuration achieves acceleration rates up to 2G and linear speeds exceeding 3m/s with positioning repeatability of ±0.003mm. Thermal deformation is minimized through optimized heat dissipation paths and optional cooling features, maintaining precision during extended operation cycles. Efficiency ratings exceed 90% due to reduced mechanical losses, while noise levels remain below 65dB even at maximum operating speeds. The design’s inherent stiffness provides natural frequencies above 200Hz, eliminating resonance issues in high-speed applications.

In industrial machinery, the DIR SERIES excels in high-speed pick-and-place systems, semiconductor manufacturing equipment, and automated assembly lines where rapid cyclic motion and precise positioning are paramount. Automotive manufacturing applications include robotic welding arms, precision press feeds, and electric vehicle battery assembly systems requiring both high throughput and micron-level accuracy. For precision equipment, these ball screws are indispensable in medical device manufacturing, optical alignment systems, and coordinate measuring machines where smooth motion quality and sub-micron precision are critical. The series’ robust construction and maintenance-free operation intervals exceeding 20,000 hours make it particularly suitable for 24/7 production environments where reliability and minimal downtime are essential.