Analysis of the mechanical properties of linear bearings and the influencing factorsIssuing time:2022-10-25 14:17Source:宁波直线轴承 Linear bearings are components that achieve linear motion through steel balls circulating or reciprocating rolling on internal tracks. During the operation of linear bearings, they generally bear lateral loads, and the internal rolling elements are subjected to complex forces and deformations. Ball linear bearings generally consist of a bearing sleeve, a cage, multiple rows of rolling elements, and annular sealing baffles at both ends. Multiple rolling elements are densely distributed inside the annular cage, and the annular sealing baffles at both ends of the inner surface of the outer ring serve as fixing devices for the cage. The research on the mechanical properties of linear bearings is mostly based on Hertz contact theory, without considering the size error of the rolling elements of linear bearings, making it difficult to achieve accurate mechanical performance calculations. In addition, the influence of factors such as the position of the load, clearance, and geometric errors of the rolling element is rarely considered, which can cause calculation errors in the force acting on the rolling element and affect the accuracy of judging the mechanical performance of the rolling element. Taking the ball linear bearing subjected to lateral load as an example, we can construct a more accurate mechanical model for calculating the force and deformation of each rolling element. Factors such as load size and position, rolling element size error, and clearance between rolling element and raceway all have an impact on the mechanical performance of the linear bearing. (1) Without considering the error and clearance of the rolling elements, when the lateral load acts on the center symmetric position of the linear bearing, each rolling element in each column along the axial direction is subjected to the same force. When the load deviates from the center symmetric position, the force on the rolling element becomes uneven. After a certain degree of deviation, only a portion of the rolling element is subjected to force in the axial column. (2) Without considering the size error of the rolling elements, as the clearance increases, the force on each row of rolling elements in the axial direction of the linear bearing is different. Some rows of forces increase with the increase of clearance, while others decrease with the increase of clearance. (3) Without considering the clearance, only one rolling element has a positive error in size, which will increase the force on that rolling element and slightly reduce the force on other rolling elements in the same circular column. If only one rolling element has a negative error in size, it will reduce the force on that rolling element, and the force on the surrounding rolling elements in the same circular column will slightly increase to maintain force balance. When considering random errors in all rolling elements of linear bearings, the force on each rolling element will be significantly different from when errors are not considered. |