Four-point contact ball bearings are a kind of split bearings, which can also be said to be a set of angular contact ball bearings that can bear bidirectional axial loads. It consists of parts such as an inner ring, an outer ring, a rolling element, and an isolation block. When there is no load or a pure radial load, the ball and the ferrule appear to be in contact at four points, which is also the origin of this name.
These bearings are designed with inner and outer raceways of peach cross-section and can be used to support axial loads acting in both directions. In addition, four-point contact ball bearings are separable constructions, and a single bearing can replace the angular contact ball bearings with a frontal or rear combination.
1. It can bear two-way axial load at the same time, which is the main feature of four-point contact ball bearings.
2. Because the contact angle between the rolling element and the ring can be automatically adjusted during operation, it can automatically adapt to the deflection and deformation of the shaft, thereby reducing the axial and radial vibration to a large extent.
3. Due to its self-aligning performance, it can be used in a variety of different working conditions, including axial, radial, inclined or torsional deformation.
4. Compared with double-row angular contact ball bearings, four-point contact ball bearings can bear greater load.
5. Compared with double-row angular contact ball bearings, four-point contact ball bearings have greater rigidity.
1. The speed is relatively low, which is usually not suitable for high-speed operation environment.
2. It cannot bear large radial load.
3. The manufacturing cost is high.
4. For pure axial loads or pure radial loads, four-point contact ball bearings are not optimal, because they are not designed to withstand these single-direction loads.
SKL thin-walled four-point contact ball bearings and flange crossed roller bearings have the characteristics of strong joint bearing capacity, high precision, small friction torque, light weight and stable operation, so they are mostly used in the waist, elbow, wrist and other parts of industrial robots.
With the continuous development of advanced manufacturing industry and the improvement of large-scale construction machinery and automobile automated production lines, the demand for various types of robots in high-end manufacturing industry is increasing, and the demand for thin-walled four-point ball bearings has also increased.
Four-point contact ball bearings can meet the user's demand for lightweight bearing. The ratio of outer diameter to inner diameter is small, the diameter of the rolling element is small, the number is large, and the bearing cross-sectional size is the same, which does not change with the change of inner diameter. Thin-walled four-point ball bearings with preloaded bearings are used for high stiffness applications and radial bearings are used for low frictional torque applications.