Patent ID: 8869317

Claim:
A buoyancy operation mechanism for a sewage suction device used in toilets, the mechanism comprising: a water tank having a bottom plate and a tank wall, wherein the bottom plate has a lower leading pole, a second pulley is located between the bottom plate and the lower leading pole; the tank wall contains an aperture, a first pulley is located outside the water tank adjacent to the aperture; an upper cover plate having an upper leading pole, wherein a third pulley is positioned on top of the upper cover plate; a hollow floating box with either a rectangular or circular cross section and a center, where the center is equipped with a leading hole, wherein a limiting barrier is located inside the leading hole with a first hoist ring and a second hoist ring positioned on the limiting barrier; a base plate having edges, with a protruding upper level along the edges, where the protruding upper level is provided with a through hole, a fourth pulley is located inside the through hole; and a top cover plate, wherein the water tank is seated on the protruding upper level of the base plate; the leading hole of the floating box is positioned over the lower leading pole of the water tank; the upper leading pole of the upper cover plate points downward inside the water tank; the top cover plate is positioned on top of the water tank; the first hoist ring of the floating box is tied to a first pulling string, where the first pulling string passes over the third pulley and the first pulley, through the aperture, then continues outside the water tank; the second hoist ring of the floating box is tied to a second pulling string, wherein the second pulling string passes over the second pulley and the fourth pulley, through the through hole, and then continues outside the water tank.