Abstract: A washing machine having a dual-purpose sensor capable of detecting a degree of vibration generated during a dewatering step as well as measuring detergent levels present in the water. The washing machine having a sensor unit installed with respect to an outer tub for holding water. The washing machine includes a microcomputer having an input port receiving an applied voltage, the input port electrically connected to a supply voltage; first and second electrodes, installed so as to be submerged in the water of the outer tub, wherein the first electrode is electrically connected to the supply voltage and the second electrode is electrically connected to ground, to thereby generate the applied voltage for input to the input port of the microcomputer; a spherical conductor disposed adjacent to the electrodes; and a support for supporting the spherical conductor.

Abstract: In a method of controlling to a water supplying step and a water draining step in a washing machine having no anti-siphoning device, an error state is determined when water supplying and water draining are simultaneously performed. The error state is determined for cases where there is no change in water level after supplying water for a predetermined time. In such cases, water is then re-supplied after a complete draining.

Abstract: Sensor for detecting both a water level and a vibration in a washing machine, which permits detection both of the water level of washing water in a washing tub and the vibration of the washing tub, including a housing which is a body of the sensor for detecting both the water level and the vibration, hydraulic pressure transmission means under the housing for moving up and down by a hydraulic pressure of the water level in a washing tub, a coil part above the hydraulic pressure transmission means having a coil with a proper inductance, a core holder on the hydraulic pressure transmission means having a core accommodated therein, the core adapted to move up and down within the coil part for varying the inductance of the coil, a cap fitted to a top portion of the coil part, a spring placed in a hollow of the coil part, and a vibration detecting means adapted to move according to the vibration of the housing for varying the inductance of the coil, whereby detecting the water level in the washing tub by substanti