Abstract: For the top loading washing machine, the motion of mounting system is firstly simplified to two degrees of freedom model, based on the analysis of the kinematic relationship, the mathematical model with two degrees of freedom is then derived by using D′Alembert principle and Lagrange method respectively. The equation of motion is solved and the amplitude-frequency curves for two degrees of freedom are drawn. At last the influence of balancer and suspension location on the tub vibration is studied. It provides one simple and convenient method for dynamic properties analysis of the front loading washing machine.

Key words: Top loading washing machine, Mounting system, Equation of motion, D′Alembert principle;, Lagrange method, Two degrees of freedom model