Patent ID: 7114355

Claim:
A washing machine, comprising: a tub installed in a cabinet; a metal bearing housing mounted in a central portion of a rear wall of the tub, wherein the bearing housing has a cylindrical aperture passing therethrough, and wherein front and rear steps are formed on the cylindrical aperture, the front and rear steps being configured to receive and support bearings; front and rear bearings installed in the front and rear steps of the bearing housing; a drum rotatably installed in the tub and having a spider formed on a rear wall of the drum; a shaft, wherein a first end of the shaft is attached to the spider of the drum such that a driving force can be transmitted from the shaft to the drum, wherein the shaft includes front and rear steps configured to receive bearings, and wherein the shaft passes through the bearing housing and is mounted on the front and rear bearings such that the front and rear bearings abut the front and rear steps on the shaft; a brass bushing mounted on the shaft between the spider and the front bearing; a connector coupled to a rear end of the shaft; a rotor coupled to the connector such that the connector and the shaft rotate with the rotor, wherein the rotor comprises one of steel and steel alloy plate, and wherein the rotor further comprises: a generally circular rear wall, a cylindrical sidewall extending from a periphery of the rear wall, wherein a bent portion is formed along a circumference of the sidewall, the bent portion including sitting surfaces configured to receive magnets, a hub formed at a center of the rear wall and having an aperture passing therethrough, wherein the aperture is configured to receive a fastener that attaches the rotor to the shaft, a plurality of cooling fins formed in the rear wall of the rotor and arranged around the hub, wherein the cooling fins extend in a radial direction, and wherein the cooling fins are configured to blow air toward the stator, and a plurality of embossings that serve to reinforce the rotor, wherein each embossing is formed between an adjacent pair of cooling fins, and wherein a drain hole is formed in each embossing; a stator attached to a rear wall of the tub, wherein the stator is surrounded by the rotor; and a supporter positioned between the rear wall of the tub and the stator, wherein the supporter is configured to maintain a concentric relationship between the tub and the stator.