Abstract: A drum washing machine including a water tub, a rotary tub rotatably provided in the water tub, a detergent feed pipe having a first end connected to the water tub and a second end disposed at an inlet of the rotary tub, and a detergent feed unit to feed a detergent contained in the water tub into the rotary tub through the detergent feed pipe, wherein the detergent feed unit dissolves the detergent before feeding the detergent into the rotary tub in response to the detergent being a powdered detergent.

Abstract: A washing machine includes a water tub improved in strength and configured to reduce an amount of washing water consumed by the washing machine. The water tub has a bottom part, and a body part upwardly extended from a periphery of the bottom part by a certain height. The body part includes at least one annular stepped portion to reduce a diameter of the body part. The water tub includes a first annular stepped portion formed at a middle of the water tub, and second and third annular stepped portions formed above and below the first annular stepped portion, respectively. The body part of the water tub is widened upwardly. Hence, the washing machine has a water tub that is strengthened and able to reduce vibration.

Abstract: An unbalance detecting method of a washing machine, wherein an unbalanced mass of a washing machine is accurately detected and classified according to input voltage variation when the unbalance is detected utilizing a ripple width of a current by a current sensor, thereby preventing errors from occurring in spin-dry process, the method comprising the steps of increasing the speed of the motor to a predetermined revolution per minute (rpm); detecting a variation of an AC input voltage according to input voltage detecting means; detecting a ripple current of an AC input current according to input current detecting means; obtaining a difference between a maximum value and a minimum value of a ripple current detected by the input current detecting step to thereby determine whether a ripple width of the current is larger than a predetermined value; calculating an unbalanced mass according to the input voltage value detected at the input voltage detecting step when it is determined that the ripple width of the curr

Abstract: A microwave oven adapted to radiate microwaves of mutually reverse phases to minimize impedance variation of a waveguide in response to load change of foodstuff, thereby maintaining an output of the microwave at a constant level regardless of load amount of the foodstuff and maintaining an electric field distribution in a cavity at a constant level as well.

Abstract: A microwave oven is disclosed in which the structure of the wave guiding tube is improved such that the variation of the impedance is minimized in spite of the variation of the load of the food, thereby making it possible to maintain the output of the microwave oven at a constant level regardless of the load of the food. The microwaves are divided into a plurality of wave streams, and the wave streams are made to have different phases. The microwave oven includes an input wave guiding tube coupled with a magnetron, for receiving microwaves from the magnetron. A first output wave guiding tube communicates to the input wave guiding tube, for receiving the microwaves from the input wave guiding tube to diffusely irradiate the microwaves into a cavity. A second wave guiding tube communicates to the input wave guiding tube, for converting the microwaves to a phase different from that of the first wave guiding tube to irradiate them into the cavity.