RU-Integrated Inner/Outer Ring Type

THK Model RU(Integrated Inner/Outer Ring Type, with high rigidity and mounting holes)

LYNBC crossed roller bearings RU series (THK corresponding to RU series, Integrated Inner/Outer ring design).Since holes are drilled for mounting, the need for a presser flange and a housing is eliminated. Also, owing to the integrated Inner/outer ring type structure with washer, there is almost no effect from installation on performance, allowing stable rotational accuracy and torque to be obtained. Can be used for both outer and inner ring rotaion.

▲ The design’s of all these crossed roller bearings RU series are based on standard structures; LYNBC can design and manufacture many other similar structures in accordance to the special and particular requirements of their customers’. If our customer’s have specific requests then the customer should identify the structure, and mounting dimensions that are required. Please contact the LYNBC Technical Center if you need any assistance in this area.  

THK Model RU (Integrated Inner/outer Ring type , with high rigidity and mounting holes )

What are THK RU Series Crossed Roller Bearings?

THK RU Series are a type of crossed roller bearing known for their high rigidity and high rotational accuracy. They are compact bearings designed to handle loads from all directions (radial, thrust, and moment) simultaneously. They are a key component in applications demanding precise and reliable motion.

Key Features and Characteristics

Crossed Roller Arrangement: This is the defining feature. Cylindrical rollers are alternately crossed at right angles, with spacers between them. This arrangement significantly increases the contact length and area, leading to a very high load capacity and stiffness.

Integrated Inner and Outer Rings: RU series often have integrated inner and outer rings. Some models also have split inner or outer rings for easier mounting.

High Rigidity: The crossed roller arrangement provides exceptional stiffness, minimizing deformation under load. This is crucial for applications requiring high precision.

High Rotational Accuracy: Precise manufacturing and assembly contribute to low runout and smooth rotation.

Compact Design: The design minimizes the overall bearing size, making it suitable for applications where space is limited.

Variety of Sizes and Types: THK offers a range of sizes and configurations within the RU series to accommodate different load and space requirements. This includes:

RU: Standard type, suitable for general applications.

RUW: Wide type, offering even higher rigidity and load capacity.

RUWX: Extra-wide type, providing maximum rigidity and load capacity.

RUJ: Models with pre-load adjustment.

RUH: High accuracy type.

Pre-load Options: Some models offer pre-load adjustments. Pre-loading eliminates backlash and further increases stiffness, particularly important in applications where precise positioning is critical.

Lubrication: Bearings require proper lubrication. THK typically provides recommendations for suitable lubricants and lubrication intervals.

Material: Typically made from high-quality bearing steel, heat-treated for optimal hardness and durability.

Benefits of Using THK RU Series

High Load Capacity: Handles combined loads (radial, axial, and moment) effectively.

High Rigidity: Resists deformation under load, ensuring accurate positioning.

High Precision: Provides smooth and accurate rotational motion.

Compact Design: Saves space in machinery and equipment.

Reduced Design Time: Integrated rings and standardized dimensions can simplify the design process.

Long Service Life: High-quality materials and construction contribute to a long and reliable operating life.

Reduced Number of Parts: By handling multiple loads with a single bearing, the overall part count can be reduced, simplifying assembly and maintenance.

Typical Applications

THK RU Series crossed roller bearings are used in a wide range of applications that demand high precision, rigidity, and load capacity. Common examples include:

Industrial Robots: Joints and actuators require precise and rigid bearings to ensure accurate movement and positioning.

Machine Tools: Rotary tables, spindles, and indexing mechanisms. Crucial for maintaining machining accuracy.

Medical Equipment: CT scanners, MRI machines, and surgical robots, where precise positioning and smooth movement are critical.

Semiconductor Manufacturing Equipment: Wafer handling and positioning systems.

Precision Turntables: High-accuracy rotation for measurement and inspection.

Aerospace Equipment: Actuators and control surfaces.

Direct Drive Motors: Supporting high-torque and high-precision direct drive applications.

Optical Instruments: Telescopes and other instruments requiring smooth and precise movement.

Important Considerations When Selecting an RU Series Bearing

Load Requirements: Determine the maximum radial load, axial load, and moment load that the bearing will experience. This is the most critical factor.

Speed Requirements: Consider the operating speed of the application. High speeds may require special lubrication and bearing designs.

Accuracy Requirements: Determine the required rotational accuracy and runout. Choose a bearing with appropriate precision specifications.

Space Constraints: Consider the available space for the bearing. Select a bearing size and configuration that fits within the application's limitations.

Pre-load Requirements: Determine if pre-loading is necessary to eliminate backlash and increase stiffness.

Operating Environment: Consider the operating temperature, humidity, and other environmental factors. Select a bearing material and lubricant that are compatible with the environment.

Mounting Method: Determine the best mounting method for the bearing. Consider the ease of installation and maintenance. THK offers models with split rings specifically for easier mounting.

Lubrication: Follow THK's recommendations for lubrication type and intervals to ensure optimal bearing performance and longevity.

Sealing: Consider the need for seals to protect the bearing from contaminants.