| 摘要 |
<p>A washing machine comprises a washing/dehydrating tank (5), a water storage tank (7) in which the washing/dehydrating tank (5) is disposed, and a sensor (15) for detecting an electric conductivity of washing water in the washing/dehydrating tank (5) and the water storage tank (7). The sensor (15) is provided with a pair of electrodes (25) to take a variation of an electric resistance of the washing water therebetween, which is representative of the electric conductivity of the washing water, thereby controlling a washing operation of the washing machine. The sensor has a CR oscillation circuit including a resistance which represents the electric conductivity of the water between the electrodes. A variation of the electric conductivity of the washing water is converted into an oscillation frequency variation of the oscillation circuit, and the operation of the washing machine is controlled on the basis of the thus varying oscillation frequency. <IMAGE></p> |
