| 摘要 |
<p>Water is supplied to a reservoir, like a pond or a rice field, through pipe (1). The lower end of pipe (1) carries a valve seat (2) made of rubber. Seat (2) is positioned inside a cylindrical box (3) with vertical grooves and upper and lower wall (3a, 3b). Box (3) is positioned in the water reservoir. Inside box (3) a float (4) is provided between walls (3a, 3b). If the water level in the reservoir is low, float (4) is in its lower position, the valve is open and water is supplied to the reservoir through pipe (1). If the reservoir is full, the water level is high enough to push the float (4) against seat (2). The valve closes automatically and no further water is fed into the reservoir.</p> |
