Cross cylindrical roller slewing bearing

Definition and operation principle of crossed cylindrical roller slewing bearing

Definition: Cross-roller type slewing bearing consists of two races. It is compact in structure, light in weight, high in manufacturing precision, small in assembly clearance, high in installation accuracy, and 1:1 cross-arrangement of rollers. The force, tipping moment and large radial force are widely used in lifting and transportation, construction machinery and military products.

Cross cylindrical roller principle: Cylindrical rollers are arranged at right angles to each other at intervals between the inner and outer rings of the bearing. They can withstand loads from all directions (such as axial, thrust or momentum loads). The internal structure of the crossed roller bearing is arranged at 90° perpendicular to each other by rollers, and spacers or spacers are arranged between the rollers to prevent the inclination of the rollers and the friction between the rollers, thereby effectively preventing the rotational torque. increase.

In addition, the contact phenomenon or the locking phenomenon of the roller does not occur, and since the inner and outer diameters are divided structures, the gap can be adjusted, and even if the preload is applied, a high-precision rotational motion can be obtained.

Application field of cross cylindrical roller slewing bearing

Cross cylindrical roller bearings have a split inner ring, a split outer ring, and an integral inner and outer ring from the outer structure. From the internal structure, there are full roller type, metal window cage and so on. Therefore, it is widely used in various occasions: joint parts or rotating parts of industrial robots, rotary tables of machining centers, rotating parts of robots, precision rotary tables, medical instruments, measuring instruments, and IC manufacturing equipment.

Use cases and technical analysis of crossed cylindrical roller slewing bearings in the robot industry:

Industrial robots typically use an articulated mechanical structure. The drive motor is independently installed in each connector, and the power amplifier circuit of the drive unit is controlled by a computer to realize the operation of the robot. The structure of an industrial robot is a closed loop system. Through the motion controller, servo drive, robot body, sensor and other components, the key products of the functional robots that people need are completed: welding robot, handling robot, painting robot, transmission robot.

The development of modern industrial robots tends to be lighter, and the bearings must be installed in a limited space that must be small and lightweight, ie lightweight. At the same time, the robot has high load, high rotation precision, high running stability, fast positioning speed, high repeatability, long life and high reliability. The required robot bearings must have high load capacity, high precision and high. Rigidity, low friction torque, long life and high reliability. Lightweight and high performance is a contradiction.

Technology: Industrial robots with thin-walled bearings not only have to ensure sufficient capacity, but also require precise positioning and flexible operation. Therefore, bearing design analysis determines the main parameters, not just the dynamic rated load as the objective function, and the rated motion Load, stiffness and friction torque are used as objective functions for multi-objective optimization design. At the same time, the finite element analysis method of thin-walled bearings based on ferrule and frame deformation is adopted.