Abstract:
Taking the linear ball bearing subjected to transverse load as the research object, the relationship between the contact force and deformation of the balls was established based on mechanical analysis. Combined with the Hertz theory and deformation coordination relation, an accurate mechanical model for calculating the contact force and deformation of each ball in linear bearing was constructed, which considered the dimensional error of the balls and the clearance of the bearing. Using MATLAB software to develop the algorithm and taking the LM8UU linear bearing as an example, the factors affecting the contact force of the balls, such as the size and position of lateral load, the dimensional error and clearance between the balls, and raceways, were systematically studied. Finally, a series of regular relationship curves were obtained. The results showed that the contact force of each ball increased with the increase of transverse load. As the transverse load moved from the middle to the edge, the distribution of force on the balls started to become uneven, with more circular columns bearing the force, but less balls bearing in each column. Clearance made the contact force decrease among most of the balls, while a small part of the balls bore more with the increase of clearance. The negative dimensional error of one ball reduced its contact force and the positive one increased its contact force. When all the balls had dimensional error, the contact force exerted on each ball would be distinctly different from that without considering dimensional error. These conclusions provided a theoretical basis for further accurate calculation of the stress distribution, deformation and fatigue life of linear bearings.