THK’s RU SERIES Cross Roller Bearing for Inner Ring Rotation represents a pinnacle of precision engineering in linear motion components, specifically engineered to deliver exceptional rotational accuracy, rigidity, and load capacity in demanding applications. This standard model features a compact, integral design where cylindrical rollers are arranged crosswise at 90 degrees to each other between the inner and outer rings, with each roller alternating direction in a single-row configuration. This unique cross-roller arrangement enables the bearing to simultaneously withstand radial, axial, and moment loads with high stiffness, eliminating the need for multiple bearing assemblies and simplifying mechanical design.

Key technical features include the use of high-grade bearing steel for all critical components, ensuring durability and long service life under heavy loads and high-speed rotation. The inner ring rotation design is optimized for applications where the shaft rotates, providing stable and precise motion control. The RU SERIES incorporates precision-ground raceways and rollers, resulting in minimal rotational torque variation and smooth, consistent operation. Standard models are available with either tapered holes or threaded holes for secure mounting, and they come pre-lubricated with high-performance grease suitable for a wide range of operating temperatures and environments. Optional seals are available to protect against contamination in harsh conditions, further enhancing reliability.

Performance advantages are substantial, starting with superior rotational accuracy, typically within microns, making these bearings ideal for precision positioning systems. The high rigidity minimizes elastic deformation under load, maintaining accuracy even during high-speed operation or when subjected to complex combined loads. This design also offers space-saving benefits, as a single RU bearing can replace traditional two-bearing setups, reducing overall assembly size and weight. Additionally, the low friction characteristics contribute to energy efficiency and reduced heat generation, extending the operational lifespan of both the bearing and the surrounding components.

Typical applications span across various high-precision industries. In industrial machinery, RU SERIES bearings are integral to rotary tables for machining centers, indexing heads, and industrial robot joints, where precise angular positioning and high load capacity are critical. Within automotive systems, they are employed in advanced manufacturing equipment, such as welding robot rotators and automated assembly line turntables, ensuring reliable performance in high-cycle production environments. In precision equipment, these bearings are found in semiconductor manufacturing devices, optical instrument stages, and medical imaging system gantries, where uncompromising accuracy and stability are paramount for sensitive operations. The versatility and robustness of the THK RU SERIES make it a cornerstone component in advancing automation and precision across modern industrial and technological sectors.