A study on unbalance vibration of brushed motor

(3rd report, coupling vibration analysis between rotor and casing)

Abstract

To increase rotational speed of brushed motor, it is important thing to reduce motor vibration. In brushed motor case, the rotor vibration affect the contact condition between brush and commutator, and degrade the performance and the life of the motor. To reduce rotor vibration of brushed motor that consists of brush, commutator, core, and fan, we evaluated rotor lateral vibration using linear vibration rotor model and selected arrangements and size of rotor component parts. In this paper, to construct linear vibration rotor model in consideration of casing stiffness, we calculated casing stiffness and mass by the finite element model of casing and connected these parameters with bearing stiffness on rotor model. Using this model, we designed low vibration rotor.