Structural Simplicity and Performance Comparison of Magnetic Lead Screws without Spiral Permanent Magnets

Abstract

Feed screws are used in various industrial machines and robots to convert rotational motions into linear motions. Mechanical screws, such as ball screws and slide screws, transmit force via frictional contacts through which noise and heat are being generated; thus, the drive efficiency is decreased. To address these problems, we have proposed some types of magnetic lead screws (MLSs) without spiral permanent magnets. The design has no spiral permanent magnets and comprises relatively few components. However, the differences in the thrust density and productivity due to the structural differences have not been reported. This paper investigates and discusses the performance and productivity of the MLSs without spiral permanent magnets based on a magnetic field analysis using a three‐dimensional finite element method. The MLSs are designed under the same size and basic design parameters. The analysis results of the thrust and torque characteristics of the MLSs are shown and compared, and their productivity is evaluated by the number of components. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.