| 摘要 |
PURPOSE: A variable rainwater storage tank is provided to store a large amount of rainwater by expanding an expansion unit and to use the stored rainwater without a pumping work. CONSTITUTION: A variable rainwater storage tank comprises a rainwater inlet pipe(10), a first water tank(20), and a second water tank(30). The rainwater inlet pipe is connected to the rooftop of a building, and the bottom end of the rainwater inlet pipe is inserted into the first water tank. A drain outlet(21) is formed on the bottom of the first water tank. The second water tank is coupled to the front of the first water tank and has a lower height than the first water tank. An expansion unit(31) is formed on the middle end of the second water tank and can be expanded to increase rainwater capacity. |
