Flush water volume regulator, flush water tank apparatus comprising said flush water volume regulator, and flush toilet comprising said flush water tank

Abstract

A flush water volume regulator is provided, capable of constraining the occurrence of a buoyancy force acting on a water reservoir, whereby flush water in the water reservoir can be circulated with flush water in a flush water tank outside the water reservoir. The flush water volume regulatorof the invention has a water reservoir, being a water reservoirdisposed inside this flush water tank, capable of storing a predetermined amount of flush water, on which an openingthrough which flush water within water reservoirand flush water outside water reservoircan pass, and an opening-closing valvefor openingduring the standby state before starting a flush and for blocking openingor reducing the opening surface area of openingwhen the water level inside flush water tankis dropping after starting a flush.