Automatic device to counteract imbalance in centrifuge loading - by temporary interruption of power supply permitting load redistribution

摘要

A device for countering imbalance in a centrifuge, partic. in the spin-drying phase of an automatic washing machine, comprises a circuit which temporarily interrupts the power supply to the motor when speed variations caused by non-uniform distribution of the load in the centrifuge are detected. The power supply to the motor, pref. a universal motor is regulated by a thyristor or triac which cops the power wave under the control of a limiter circuit. The current passing through the motor is monitored by a measuring device and compared with a control function by a comparator, whose output triggers the limiter circuit. The device prevents damage to the machine or its surrounding due to violent vibration caused by imbalanced loads, by automatically permitting the load to redistribute itself, or stopping the machine if the vibration persists.