US Patent 7124961 Sprayer system

A sprayer system includes one or more spray nozzle systems and a recirculation line which contains a Venturi for recirculation of non-sprayed liquid into a tank during breaks in spraying. To facilitate circulation, restrictors are placed in an upstream area of each nozzle system feeding line, and a downstream control valve is inserted between each nozzle system and the recirculation line. Each nozzle system can be independently controlled. Closing a control valve activates the spraying system associated with that valve, whereas opening the valve enables the liquid to circulate through the recirculation line into the tank to prevent unwanted dripping, demixing and depositing.