DRAIN BASIN

PROBLEM TO BE SOLVED: To provide a drain basin capable of efficiently draining foreign matter easy to float on water. SOLUTION: The drain basin includes a tank 2 in which drainage containing foreign matter having a specific gravity smaller than that of water is amassed, and a drain pipe 3 which drains drainage amassed in the tank 2 out of the tank 2. The drain basin also includes a return pipe 4 which branches out from the drain pipe 3 to cause drainage to flow into the tank 2. A submerged pump 5 is connected to the suction side of the drain pipe 3, and a suction inlet 8 of the submerged pump 5 is set open near the center of the bottom face of the tank 2. With the submerged pump 5, drainage sent from the tank 2 to the drain pipe 3 is caused to flow through the return pipe 4 into the tank 2, which create a swirling flow in drainage amassed in the tank 2 to stir drainage in the tank 2. As a result, a swirling flow of drainage in the tank 2 carries foreign matter easy to float on water to the suction inlet 8 of the pump 5 as the foreign matter swirl in the tank 2. The foreign matter are thus efficiently discharged out of the tank 2. COPYRIGHT: (C)2010,JPO&INPIT