Contact Deformation of Machine Tool Slideway and Its Effect on Machining Accuracy

Abstract

The slider's three-dimensional displacements due to the contact deformation at sliding joints are analyzed. The sliding joints are represented by non-linear spring elements which are distributed evenly on the sliding face, and the kinematic model of a slider including the sliding contacts is introduced. By using this model, the slider's three-dimensional displacements caused by any external force can be analyzed. It is shown that the analysis can well explain the experimental results which were made through the model of an existing machining center's table. Secondly, the analyzed slider's displacements are converted to the machining error components, and the effect of contact deformation is evaluated. The component which affects most the machining accuracy is regarded, and the corresponding slideway is redesigned to increase its contact stiffness. By repeating this process, the optimal slideway specification can be decided.