THK’s Cross Roller Bearing for Inner Ring Rotation Model RAU in the Small Diameter, 5 mm Thin Type SERIES represents a pinnacle of precision engineering designed for applications demanding minimal space without compromising performance. This bearing features a compact cross roller arrangement where cylindrical rollers are alternately positioned at right angles between the inner and outer rings. This configuration allows the bearing to simultaneously withstand radial, axial, and moment loads with high rigidity and rotational accuracy. The inner ring rotation design is optimized for scenarios where the shaft is stationary, and the housing rotates, making it ideal for integrated assembly in compact machinery. With a slim profile of just 5 mm in cross-section, this series excels in environments where space constraints are critical, yet high load capacity and precise motion control are non-negotiable.

Key technical features include the use of high-grade steel for rollers and rings, ensuring durability and resistance to deformation under stress. The bearing incorporates a sealed structure to prevent contamination from dust, debris, or moisture, thereby extending service life in harsh industrial settings. Precision grinding of raceways and rollers guarantees smooth, low-friction rotation with minimal vibration and noise, critical for high-speed operations. Additionally, the RAU series is designed for easy installation, with pre-drilled mounting holes in the outer ring that simplify integration into machinery frames or rotating components. Its lightweight construction reduces inertia, enabling rapid acceleration and deceleration in dynamic applications.

Performance advantages of this bearing are substantial, starting with its ability to handle complex load combinations in a single unit, eliminating the need for multiple bearing setups and saving valuable space. The cross roller design ensures high rotational accuracy, with minimal runout, making it suitable for precision positioning systems. Its thin type construction allows for a lower center of gravity in assemblies, enhancing stability in automated equipment. The bearing’s low torque characteristics contribute to energy efficiency, reducing power consumption in continuous operation. Moreover, its robust sealing mechanism maintains lubrication integrity, minimizing maintenance intervals and downtime in demanding environments like automotive or semiconductor manufacturing.

Typical applications span a wide range of industries, including industrial robotics, where the RAU series is used in joint axes, rotary tables, and manipulator arms to provide smooth, precise rotation in confined spaces. In automotive systems, it finds use in electric power steering mechanisms, transmission components, and sensor mounts, where reliability and compactness are crucial for vehicle performance and safety. Precision equipment such as medical devices, optical instruments, and CNC machining centers leverage this bearing for its accuracy in rotary stages, indexing heads, and measuring apparatus. Overall, the THK RAU Small Diameter Series delivers a reliable solution for high-precision, space-sensitive applications, driving efficiency and innovation across advanced machinery sectors.