The direct-injection spraying device, in particular for an agricultural vehicle, according to the invention includes a main tank, at least one spray boom, and a circuit connecting the tank to the boom. comprises:The circuit includes a main pump and a bypass for controlling the flow rate in the boom in accordance with the traveling speed of the vehicle.At least one active substance store is connected to the circuit by a metering pump.The device further includes a cyclone mixer capable of receiving, as input, the liquid from the main tank, and the pressurized liquids coming from the active substance store, and capable of eliminating the boom as output.
