Magnetic Lead Screw Mechanism and its Application to Linear Positioning System

In this paper, first, a new type of magnetic lead screw mechanism (MLSM) which is comprised of a conventional steel lead screw and a nut of permanent magnet is proposed. To analyze basic characteristics, experimental MLSMs are made, and the flux density of a magnetic nut and the axial carrying load of the MLSMs are measured and simulated. Finally, to evaluate the effectiveness of the MLSM as a machine element, a linear positioning system which consists of the MLSM, a linear motion air guide and a brushless DC servomotor is constructed. Experimental results prove that the positioning system using the MLSM with an appropriate feedback system can work well as those using ball lead screw mechanisms or air lead screw mechanisms.