Patent ID: 7614261

Claim:
A drum type washing machine comprising: a housing; a water tub mounted in the housing to contain wash water therein, the water tub having an opening formed at a front side of the water tub for accessing laundry to and from the water tub, a rotating tub rotatably mounted in the water tub; a rotating shaft horizontally mounted at a rear end of the rotating tub; a water supply pipe installed at a top of the housing for receiving wash water from an external water supply source; a detergent container installed at the top of the housing for containing detergent and mixing a detergent with the wash water supplied via the water supply pipe; a drainage pump and a drainage hose installed at a bottom of the housing in order to drain wash water to the outside of the housing; and first and second connection pipes extending to the housing, from the water tub to circulate outside air to and from the water tub, wherein first ends of the first and second connection pipes are connected to a circumference of the water tub, second ends of the first and second connection pipes form first and second vent holes, respectively and the first vent hole is positioned higher than the second vent hole, and wherein the first and second connection pipes provide natural ventilation in the water tub to reduce a level of humidity within the water tub without a blower device.