Patent ID: 7814769

Claim:
A drum type washing machine comprising: a housing forming an external appearance of the drum type washing machine; a water reservoir accommodated in the housing to receive water therein; a spin tub disposed in the water reservoir, which is rotated by receiving rotational force from a driving motor through a rotating shaft, the spin tub including a spin tub body having a cylindrical structure formed with a plurality of pores allowing water and air to pass through the spin tub, the spin tub body having a front cover with a laundry receiving opening provided at a front side thereof and a rear cover provided at a rear side thereof; a rear balancer having an annular shape and being coupled to the rear cover of the spin tub to reduce vibration of the spin tub during rotation thereof; and a shaft flange including a hub section to fixedly install the rotating shaft and a plurality of arm sections extending radially outward from the hub section and mounted to the spin tub so as to uniformly transfer the rotational force to the spin tub, wherein the rear balancer is disposed in an annular groove formed in the rear cover of the spin tub and becomes sandwiched between the rear cover and the arm sections of the shaft flange when an outer end portion of each respective arm section of the shaft flange is fixedly connected to a rear end portion of the spin tub body, and wherein the depth of the annular groove formed in the rear cover is sized such that, when the rear balancer is sandwiched between the rear cover and the arm sections, a rear surface of the rear balancer does not extend beyond a hollow space region defined by the annular groove, enabling the arm sections to support the rear balancer without having to form recesses in portions of the arm sections that engage the rear balancer.