US Patent 11219344 Robot vacuum cleaner

A robot vacuum cleaner includes a main body that moves along a surface, draws in dust from the surface, filters the dust, and discharges air. A water tank is detachably mounted on a lower surface of the main body, and a damp cloth is mounted to the water tank. The water tank stores water in a filling space and supplies water from the filling space through a water supply unit mounted on a lower surface of the water tank to the damp cloth. An air inlet is formed on an upper surface of the water tank. An air inflow member selectively opens the air inlet to allow outside air to flow into the filling space when the main body moves, and closes the air hole when the main body stops moving.