PURPOSE: To constitute the device so that even at the time of washing, alkaline ion water, and acidic ion water are poured from a pouring port from which alkaline ion water is poured, and from a pouring port from which acidic ion water is poured, respectively, at the time of regular use.

CONSTITUTION: The device is provided with switching contacts 15, 16 for applying a voltage of opposite polarity to the remaining electrodes which are not selected, as for the selected electrode to be washed, in two pairs of electrodes 9, 10 and 11, 12, opening/closing contacts 17, 18 which are opened and closed, respectively by interlocking with switching of these contacts and apply a voltage to the selected electrode through resistances 23, 24, and a switching contact 21 for applying a higher voltage than an applied voltage to the electrode at the time of regular use at the time when such washing is not executed.