Patent ID: 8734099

Claim:
A water pump for a vehicle, the water pump comprising: a pump housing; a drive shaft which is inserted into the pump housing, and which includes an axial portion surrounded by the pump housing; an impeller fixed on a first end portion of the drive shaft, and arranged to discharge a fluid sucked from an axial direction, in a radial direction by rotating by a centrifugal force; a pulley arranged to transmit a rotational driving force from an outside to the drive shaft, the pulley including; a fixing portion fixed on a second end portion of the drive shaft, a first radial extension portion which is connected with the fixing portion, and which extends radially outside the drive shaft, and a first axial extension portion which is connected with the first radial extension portion, and which extends in the axial direction toward the first end side of the drive shaft; a seal ball bearing which is disposed between an inner circumference surface of the first axial extension portion and an outer circumference surface of a cylindrical portion that is formed at a first end portion of the pump housing, and that confronts the inner circumference surface of the first axial extension portion, and which includes seal members located at both axial ends of the seal ball bearing in the axial direction, and arranged to liquid-tightly seal an inside of the seal ball bearing; and a plate member disposed between an end portion of the seal ball bearing which is on an impeller side and a stepped portion which is adjacent to the cylindrical portion, and arranged to cover an end surface of the seal ball bearing which is on the impeller side, the plate member having a thickness smaller than a thickness of the stepped portion, and including a separating portion which is separated from the end portion of the seal ball bearing; wherein the plate member includes an outermost circumference portion formed by bending in the axial direction; and the outermost circumference portion of the plate member extends along an extension direction of the first axial extension portion.