A normally closed solenoid valve, comprising: a fixed core; a valve portion for opening and closing a flow path of a hydraulic fluid,MULTI-FUNCTIONAL WATER PUMP CONTROL VALVE the valve portion including a valve seat and a valve body disposed opposed to the valve seat to be seated therein; Check Valvesa movable core disposed between the fixed core and the valve seat, which is capable of advancing and retreating along with the valve body with respect to the valve seat; a resilient biasing member for biasing the movable core in a valve-closing direction along which the valve body is seated in the valve seat for closing the valve; and a coil for generating an attracting force between the movable core and the fixed core when energized to cause the movable core to retreat in a valve-opening direction from an initial position thereof where the valve portion is in a closed state,Hydraulic control valves the attracting force acted against a biasing force exerted by the resilient biasing member; wherein, an assembling allowance range of a spacing distance between the fixed core and the movable core at the initial position is established, a characteristic graph line of spacing distance/attracting force is defined for expressing a relation between the attracting force and the spacing distance, and the characteristic graph line provides attracting forces at a minimum spacing distance L1 and a maximum spacing distance L2 within the assembling allowance range, which are connectable by a straight line having a slope A (N/mm), and the compression resiliency coefficient of the resilient biasing member in the assembling allowance range is substantially the slope A (N/mm), such that the biasing force of the resilient biasing member has an oppositely directed and substantially equal force to the attracting force over the assembling allowance range.

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