Washing machine or an apparatus having a rotatable container

Abstract

A washing machine according to the present invention includes a pressure sensor provided at a rod holding plate holding a suspension rod with which an outer tub is suspended. The pressure sensor is constructed so that a coil is wound around a magnetostrictive element whose magnetic characteristic changes when it is expanded, compressed or twisted by an external force. The change in the magnetic characteristic is converted to the change in the inductance of the coil, and an oscillating signal of a frequency corresponding to the inductance generated. Based on the frequency of the signal, the load on the pressure sensor is detected. Before supplying water, the amount of the laundry contained in a wash-and-extraction tub is detected based on the output of the pressure sensor, and an object water level corresponding to the amount is determined. After that, a water supply valve is opened to start supplying water into the wash-and-extraction tub. The weight of water supplied is monitored based on the output of the pressure sensor, and the weight is converted to a water level. When the monitored water level has attained the object water level, the water supply is stopped. Thus, the pressure sensor functions not only as a load detector but also as a level sensor.

Dependencies are inferred from the claim text.