Balancing module and washing machine having the same

A washing machine comprising:

• a rotating basket in which laundry is accommodated, the rotating basket being configured to be rotated upon receiving rotation power from a drive source;
• at least one balancer housing mounted to the rotating basket, the balancer housing internally having an annular channel, the balancer housing includes at least one electrode provided in a circumferential direction of the balancer housing and configured to transmit electric power from an external power source;
• and
• at least one balancing module movably disposed in the channel to alleviate load unbalance caused during rotation of the rotating basket,
• wherein the balancing module includes
• a main plate;
• at least one mass body provided at the main plate;
• a drive unit mounted to the main plate to assist the balancing module in moving to a position where the balancing module alleviates load unbalance of the rotating basket;
• a brush configured to transmit the electric power to the drive unit, the brush being placed behind the drive unit to come into physical contact with the at least one electrode;
• and
• bearings mounted at both ends of the balancing module, the bearings being configured to prevent the main plate and the at least one mass body from coming into contact with an inner surface of the balancer housing,
• wherein each of the bearings includes a circumferential surface configured to come into contact with the inner surface of the balancer housing, the circumferential surface having a corrugated cross section including contact ridges and valleys.