A dynamic model and numerical study on the liquid balancer used in an automatic washing machine

The rotational system of an automatic washing machine has two major technical difficulties. One is the collision of the tub against the frame at the beginning of its early spinning stage. A factor that causes such instability of the rotational object can be attributed to the deflection of the liquid inside the liquid balancer due to the unbalance mass. This study proposes the installation of a middle plate to avoid the deflection of the liquid and a CFD method is used to verify its effectiveness. The other is the whirling vibration occurred during the high speed rotation of the basket and it shakes the center of its rotational axis. This is because the balancer cannot generate enough restoration forces during its high speed rotation. It is necessary to employ the multi-race in the balancer in order to increase restoration forces. The analysis for the configuration has been performed using a dynamic model.