Patent ID: 7753290

Claim:
A self-contained, powered sprayer for generating a foam effluent comprising: a tank defining a reservoir for holding a liquid, said tank including wheels to facilitate movement of said tank; a spray gun having a flow controller and defining a mixing chamber, said spray gun having an exit for said foam effluent, said mixing chamber substantially located near the exit, said flow controller having a manually operable valve for selectively controlling flow of effluent from the sprayer; a pump mounted to said tank, said pump having an inlet and an outlet; a liquid supply line extending from said pump to said flow controller; a liquid withdrawal line extending from said pump to said reservoir; a compressor mounted to said tank; an air supply line extending from said compressor to said flow controller; a one-way check valve preventing liquid from back-flowing out of the mixing chamber down the air supply line, said liquid supply line permitting two-way flow whereby pressurized air is capable of back-flowing down the liquid supply line if the tank is dry, the pump runs out of liquid, or the liquid line is leaking; and a control means for engaging and disengaging said pump and said compressor in response to manual operation of said flow controller.