Balancer and washing machine having the same

摘要

A balancer (100) of a washing machine (1) having improved balancing performance. The balancer includes a balancer housing (110) having an annular channel (110a) therein, at least one mass (141) movably disposed in the channel at least one groove (121) recessed in an inner surface of the balancer housing so as to accommodate the mass, and at least one magnet (160) coupled to an outer surface of the balancer housing to restrict the mass accommodated in the groove when an RPM of the drum is within a specific RPM range. The magnet is configured as a plurality of N poles and S poles which are arranged alternately, and the outermost pole of the magnet among the plural N poles and S poles has a relatively shorter length than another adjacent pole.