Patent ID: 8436703

Claim:
A water pump of clutch type which receives a coolant, pressurizes the coolant by a rotation of an impeller fixed to a shaft, and supplies the pressurized coolant to a cooling circuit, the water pump comprising: a pulley connected to a crankshaft so as to rotate according to a rotation of the crankshaft; a hub at which the shaft is mounted so as to rotate together with the shaft; a pin selectively connecting the hub to the pulley; an elastic member always exerting elastic force on the pin; and a coil selectively applying magnetic force to the pin to an opposite direction of the elastic force, wherein the coil is wound on a case and includes first and second coils with different cross-sectional area, the first coil and the second coil are wound on the case by turns, and the first coil and the second coil are disposed to form a zigzag shape.