Flexible wheel displacements for electromagnetic harmonic movable tooth drive system

Abstract

In this paper, the structure and operating principle of the electromagnetic harmonic movable tooth drive system is introduced. Equations of the magnetic density and the electromagnetic force are given. The force model on the flexible wheel under magnetic force is presented. The equivalent concentrated force applied to the flexible wheel is determined. Based on it, the displacement equations of the flexible wheel are deduced. Using these equations, the displacement distribution of the flexible wheel and its changes along with the main parameters are investigated. Relationship between coil current and the maximum radial displacement is determined. The limit current corresponding to the limit radial displacement is obtained and its changes along with the main parameters are analyzed. The results show that the displacements of flexible wheel increase with the radius of flexible wheel and the coil current, and decrease with the initial air gap and the thickness of flexible wheel. A limit current under which the flexible ring will be buckled occurs under electromagnetic force. The limit current corresponding to the limit displacement increases with the thickness of flexible wheel, the pole pair number and the air gap, and decreases with the radius of flexible wheel. The results can be used to design and analyze the drive system.

Keywords

Electromagnetic drive harmonic drive displacement force model limit current

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