A 6 degree-of-freedom dynamic model of a vertical-axis washing machine is established to simulate dynamic behavior of the system. A spin-basket is rotating with an unbalance mass in the tub which is hung to the cabinet by four suspension bars. Transient histories of displacements of the tub are obtained for a spin-dry cycle accelerating from 0 to 1100rpm. The effect of a liquid balancer is considered only for the steady state.
The influence of several design variables from the suspension is investigated for the vibration amplitude of the tub. The Taguchi method is employed for this purpose using the L9 orthogonal array. At the optimum obtained, the amplitude of the tub has been reduced by 18.2% as compared with that of the original design. It has been shown that the model, although simple, is very suitable for study of dynamic behavior of the suspended mass and design of the suspension system.