US Patent 8191798 Agricultural field sprayer and process for its operation

An agricultural field sprayer (10) includes an electrically driven pump (50) locatable directly under sprayer fluid tank for conveying the fluid from the tank to a supply line. A return line (54) connects the pump (50) to the tank (22), and a sprayer line (32) connecting the pump (50) to an application assembly (20). The return line (54) and the sprayer line (32) include electrically operated control valves (68, 64), and an electronic control system (56) operates the motor (46) and the control valves (64, 68) as a function of different variables including field sprayer speed and sprayer fluid characteristics. The valve and motor controls and an additional valve-controlled return line facilitate numerous operational modes including tank fill, rinse, recirculation, spray, partial width spray, and stop modes.