Nozzle of cleaner and methods for controlling same

A method for controlling a nozzle of a cleaner, the cleaner including:

• a nozzle main body having a suction flow path through which air is suctioned;
• a first rotation cleaning unit and a second rotation cleaning unit spaced apart in a left and right direction on a lower side of the nozzle main body, each of the first rotation cleaning unit and the second rotation cleaning unit including a rotation plate to which a mop is attachable;
• a first driving device disposed on one side of a flow path extending in a front and rear direction in the suction flow path and including a first driving motor for driving the first rotation cleaning unit;
• a second driving device disposed on the other side of the flow path extending in the front and rear direction in the suction flow path and including a second driving motor for driving the second rotation cleaning unit;
• a water tank detachably mounted on an upper side of the nozzle main body and configured to store water to be supplied to each of the first and second rotation cleaning units;
• a water supply flow path provided in the nozzle main body and communicating with the water tank so as to supply water from the water tank to each of the first and second rotation cleaning units;
• a first sensing unit configured to sense a rotation speed of the first driving motor;
• a second sensing unit configured to sense a rotation speed of the second driving motor;
• and
• a control unit, the method comprising:
• turning on the first and second driving motors;
• detecting, by the first and second sensing units, rotation speeds of the first and second driving motors, respectively;
• comparing, by the control unit, the rotation speeds of the first and second driving motors;
• and
• selectively adjusting the rotation speeds of the first and second driving motors according to a comparison result.