Crossed roller bearings are a type of high-precision bearing with a unique structure that allows them to support radial, axial, and moment loads simultaneously. Their structure and design offer high rigidity and compact size, making them suitable for applications requiring high accuracy and stiffness, such as robotics, machine tools, and medical equipment.
Inner and Outer Rings:
Inner Ring: Often split into two pieces to facilitate the insertion of the rollers and retainers.
Outer Ring: Can be one piece or split, depending on the design. The outer ring typically has a groove to house the rollers and retainers.
Rollers:
Cylindrical rollers are positioned between the inner and outer rings.
Rollers are arranged at right angles (90 degrees) to each other in an alternating pattern, which allows the bearing to handle loads from multiple directions.
Separator/Retainer:
A retainer or separator is used to keep the rollers in their correct positions and to prevent them from contacting each other.
The retainer can be made of materials like metal or plastic, ensuring smooth rotation and reduced friction.
Raceways:
Both the inner and outer rings have precisely machined raceways that match the rollers' profiles.
The raceways ensure the rollers are guided accurately, distributing the loads evenly across the rollers.
High Load Capacity:
The crossed arrangement of rollers allows the bearing to support loads in all directions (radial, axial, and moment) with high capacity.
High Rigidity and Precision:
The compact design and precise manufacturing of the raceways and rollers provide high rigidity and accuracy, which is crucial for precision applications.
Compact Design:
Crossed roller bearings can achieve high load capacity and rigidity with a smaller footprint compared to other bearing types, saving space in machinery and equipment designs.
Smooth Rotation:
The use of separators/retainers reduces friction between the rollers, ensuring smooth and precise rotation.
Easy Installation:
The split inner or outer ring design facilitates easy installation and assembly of the bearing.
Crossed roller bearings are used in a variety of high-precision and high-rigidity applications, including:
Robotics: Joints and rotating parts requiring high accuracy and load capacity.
Machine Tools: Precision spindles, rotary tables, and indexing heads.
Medical Equipment: Imaging devices and surgical robots where precision and reliability are critical.
Aerospace: Flight control systems and gimbals.
Semiconductor Manufacturing: Wafer-handling systems and inspection equipment.
Crossed roller bearings are a specialized type of bearing with a unique structure that provides high load capacity, rigidity, and precision in a compact design. Their ability to support loads in all directions makes them ideal for applications requiring high accuracy and reliability.