Development And Application Of Optimized Selection Tool For Ball Screw

Ball screw is widely used in equipment manufacturing, automobile transportation, aerospace and other fields. Optimized selection is crucial for ball screw performance. So research about development and application of tool for ball screw optimized selection in design process is meaningful and important.Firstly, this thesis starts from the study of ball screw optimized selection theory in design process. "3-Step" optimized selection method (Preliminary Selection, Performance Verification and Final Optimized Selection) is proposed. In the Preliminary Selection, lead, bottom diameter and dynamic load rating are chosen as three key standards. The Performance Verification is complemented with a more simplified stiffness algorithm. Finally stiffness, load distribution, life and geometric dimensions are used as criteria of optimization to choose the final ball screw which is an innovative point of this thesis. An innovative mechanical model——Equivalent Spring Theoretical Model, based on elastomeric properties is proposed for the research of ball screw load distribution. This model can help us quickly and efficiently calculate the load distribution and lays the theoretical foundation for quantified optimization standards in ball screw selection process. The calculation equations of Unit Equivalent Spring Stiffness are developed. The factors influencing load distribution are listed and analysed. Two methods Numerical Calculation and Finite Element Simulation are used to prove the correctness of Equivalent Spring Theoretical Model. After analyzing the load distribution, this thesis then focuses on the study of ball screw contact stiffness. Axial contact deformation coefficient which is independent of work load is proposed and provides a theoretical support for the ball screw quantitative stiffness selection criteria. In this section, relationship between stress distribution and contact deformation is developed and factors influencing ball screw axial contact stiffness are analysed. After analyzing user needs and existing products, software framework and function modules are defined. Finally, optimized selection tool of ball screw is designed and developed according to "3-Step" method.