The THK NS SERIES Ball Screw with Rotary Nut represents a specialized linear motion solution engineered for applications requiring continuous rotation of the nut while the screw shaft remains stationary. This configuration is particularly advantageous in space-constrained designs or systems demanding simplified drive arrangements. The NS SERIES incorporates precision-ground ball screws with a uniquely designed rotary nut that integrates a compact, high-torque motor directly into the assembly. This design eliminates the need for external couplings or complex drive mechanisms, reducing overall system footprint and enhancing mechanical efficiency.

Key technical features include the utilization of THK’s proprietary precision grinding technology, ensuring exceptional lead accuracy and minimal axial play. The ball screw employs a large-diameter ball circuit with optimized contact angles, distributing load evenly across multiple recirculating balls. This configuration significantly increases dynamic load capacity while maintaining smooth, low-friction operation. The rotary nut assembly features precision angular contact bearings pre-loaded to eliminate backlash, coupled with advanced sealing systems that provide robust protection against contaminants. Electrical integration is facilitated through standardized motor interfaces supporting various servo and stepper motor configurations, with optional encoders for closed-loop position control.

Performance advantages are substantial across multiple operational parameters. The direct-drive rotary nut configuration achieves rotational speeds up to 3,000 rpm while maintaining positioning accuracy within ±5 μm per 300 mm travel. High mechanical efficiency exceeding 90% reduces power consumption and heat generation, enabling continuous duty cycles in demanding environments. The compact design reduces overall system weight by up to 40% compared to conventional screw-driven systems, while the integrated motor eliminates alignment issues common with coupled designs. Enhanced stiffness characteristics provide improved dynamic response with acceleration capabilities exceeding 2G, making the system ideal for high-throughput applications.

Typical industrial applications span multiple sectors where precision motion control is critical. In industrial robotics, NS SERIES units facilitate compact joint actuation in articulated arms and gantry systems, enabling precise positioning in welding, dispensing, and assembly operations. Automotive manufacturing systems employ these components in electronic power steering mechanisms, active suspension controls, and automated transmission systems where reliability and compact packaging are essential. Precision equipment applications include semiconductor manufacturing apparatus, where the series provides nanometer-level positioning in wafer handling and lithography stages, and medical imaging systems requiring vibration-free linear motion in CT scanner gantries and MRI positioning tables. The combination of high precision, compact design, and reliability makes the NS SERIES particularly valuable in automated test equipment, optical alignment systems, and aerospace actuation systems where performance cannot be compromised.