In recent years, with the development of manufacturing technology, the demand for various types of robots with modern manufacturing technology has increased. Such as large-scale engineering machinery, automobiles, home appliances and other automated production lines, as well as deep-sea manned submersibles, humanoid bionic robots and painting, arc welding, spot welding, assembly, handling industrial robots that enhance the country's high-tech strategic position. Special bearings for key supporting robots have an important impact on key performance indicators such as robot operation stability, repeated positioning accuracy, motion accuracy and work reliability.

At present, there are many types of bearings for industrial robots, such as thin-walled deep groove ball bearings, thin-walled angular contact ball bearings, thin-walled four-point contact ball bearings and thin-walled cross roller bearings. Because thin-walled four-point contact ball bearings and wall cross roller bearings have the characteristics of strong combined load bearing capacity, high precision, small friction torque, light weight, and stable operation, they are mostly used in the waist, elbows, wrists and other parts of industrial robots.

Ⅰ Thin-walled four-point contact ball bearing structure

The thin-walled four-point contact ball bearing for industrial robots usually has a structure with or without a seal ring. It is mainly composed of an inner ring, an outer ring, a cage, a steel ball or a non-contact seal ring. The inner and outer rings are integral structures, the steel ball is in four-point contact with the inner and outer ring grooves, and the cage is a crown-shaped insert structure. It is suitable for installation in the wrist, elbow and other joints of industrial robots.

Ⅱ Features of thin-walled sealed four-point contact ball bearings

1. The ratio of the outer diameter to the inner diameter is small, the rolling element diameter is small, and the number is large. Compared with the standard bearing with the same inner diameter, its weight is about 5% of the standard bearing, and the cross-sectional area is about 20% of the standard bearing.

2. Fixed-section bearings: Thin-walled four-point contact ball bearing series, the bearing cross-sectional dimensions are the same and do not change with the changes in the inner and outer diameters.

3. It can withstand radial load, bidirectional thrust load and overturning moment, which is equivalent to two sets of angular contact ball bearings installed back to back, but its width is only equivalent to the width of one set of angular contact ball bearings.