Patent ID: 8490441

Claim:
A washing machine having a tub having an open front side and a closed rear wall and a drum rotatably mounted within the tub, the rear wall of the tub comprising: a circumferential rib formed in an outer surface of the rear wall of the tub; at least two gate parts formed after allowing resin to be injected through a first portion of a mold to form the rear wall of tub, the at least two gate parts being disposed at the circumferential rib formed in the outer surface of the rear wall of the tub; and a reinforcing part formed adjacent to each of the at least two gate parts, the reinforcing part being formed by a second portion of the mold which has been enlarged to improve inflow of the resin, wherein a thickness of the reinforcing part in an injecting direction of the resin is thicker than portions of the rear wall of the tub disposed immediately adjacent the reinforcing part opposite the respective rib, and wherein the reinforcing part is substantially rectangular in shape and extends from the circumferential rib a predetermined distance inwardly in a radial direction of the rear wall.