Conventionally, a washer fluid spraying apparatus for a vehicle etc. that sprays the washer fluid stored in a tank to a windshield is known. In addition, such a washer fluid spraying apparatus alerts a driver with a warning light, etc., when the amount of remaining washer fluid in the tank decreases. Further, one known washer fluid spraying apparatus has a control apparatus that changes the spraying amount of the washer fluid so as to be different from that in a normal operation by intermittently driving a motor that drives a washer pump when the amount of the remaining washer fluid in the tank is decreased (for example, see Japanese Laid Open Utility Model Patent No. 62-192965). Another known washer fluid spraying apparatus includes a control apparatus that decreases the amount of the sprayed washer fluid according to the level of the remaining washer fluid when the amount of the remaining washer fluid in the tank is decreased (for example, see Japanese Laid Open Patent No. 2005-75218).
However, since in the above-mentioned prior art, the amount of the remaining washer fluid is electrically detected, and the washer pump is controlled according to the remaining amount, it is necessary to have electric parts such as a sensor that detects the amount of the remaining washer fluid, a control circuit that contains an amplifier harness that changes the amount of the sprayed washer pump, and a warning light, thereby increasing manufacturing costs.