FLUSHING WATER TANK APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a flushing water tank apparatus capable of surely suppressing the unevenness of the quantity of flushing water supplied to a toilet bowl from a flushing water tank.SOLUTION: This flushing water tank apparatus 18 includes: the flushing water tank 20 which has a drain outlet 20a formed in a bottom surface; a drain valve 40 which opens/closes the drain outlet of the flushing water tank and the density of which is higher than water; a drive unit 42 which lifts the drain valve by an electric driving force so as to supply the flushing water to the toilet bowl from the drain outlet; and a controller 28 which changes an opening time of the drain valve and controls the drive unit so as to supply the at least two kinds of quantities of flushing water for high-level and low-level flushing operations from the drain outlet. The controller controls the speed of lifting the drain valve by the drive unit, in a predetermined speed range in which the quantity of flushing water discharged from the drain outlet is not affected by the ascent speed of the drain valve.