Patent attributes
A valve includes a hollow pipe defining a first opening and a second opening aligning with each other. A first passage, a second passage, a third passage and a fourth passage are respectively defined in an inner surface of the hollow pipe and communicate with each other. A piston is received in the hollow pipe and forms a first flange and a second flange thereon. A first stop is formed above the first flange and has long sides and short sides. A second stop is formed below the second flange and has long sides and short sides. The first flange and the second flange blocking the third passage and the fourth passage depends on the short sides/long sides being aligned with the third passage and the fourth passage, whereby water discharge path is controlled easily and exactly.