| 摘要 |
<p>Directional spray heads (20A, 20B) on each side of each tower (68) over the wheels (62A, 62B) spray water behind the trailing wheel and not in front of the wheels. A control box activates the direction of travel of the wheels at the towers through a tower box at each tower. Solenoids wired to the tower box for switching power alternately to each wheel, switch the water flow via the solenoids to directional spray sprinklers spraying behind the trailing wheel.</p> |
