PURPOSE: To suck whole excrement with no remaining left without installation of a larger-sized vacuum pump by closing a connecting hole at the bottom of a storing part by water supplied before and during excretion and sucking abruptly filthy things comprising excrement and water in the storing part after excretion.

CONSTITUTION: When a degree of vacuum in a lower part of a tank 5 is raised by driving a vacuum pump 6 to work and a controlling valve 480 is made to be a state of fully opened to atmosphere from a state of opening, an exhaust pressure, which has been caused by the difference of pressure at the pinch valve 41 between the side of a filthy things tank and the side of the cup unit 2 and also at a gap between an exterior and an inner tube pipe of the pinch valve 41, disappears and becomes an atmospheric pressure. Then, the passage of the inner tube is made open by the force which is generated to regain the previous O-shaped section by a restoring force of elasticity. Because of this, the whole space down to the connecting hole 24 at the bottom of the storing part 23, immediately takes the same degree of vacuum as in the tank for filthy things and this difference in the pressure makes the filthy things suck into the tank for filthy things from the storing part 23.