FOAM GENERATING APPARATUS AND METHOD

摘要

FOAM GENERATING APPARATUS AND METHOD A foam generating apparatus can be attached to a water bearing hose and comprises an eductor nozzle to receive water and foam concentrate, and a foam generating nozzle to discharge a foam/water mixture therethrough. A foam concentrate conduit delivers concentrate to the eductor nozzle and has a concentrate valve to control flow therethrough, e.g. a one-way check valve to prevent water from passing outwardly through the foam concentrate conduit to dilute the concentrate. A delivery manifold communicates the foam concentrate conduit with a suction port of the eductor nozzle and extends peripherally around the suction port to permit foam concentrate to be drawn into the eductor nozzle for discharge therethrough. The foam generating nozzle receives the foam/water mixture and has air entrainment openings to admit air into the mixture and an agitator jet orifice for agitating the mixture located generally adjacent the air entrainment openings. The agitator jet orifice has interconnected inlet and outlet jet openings in series, the outlet jet opening being larger than the inlet jet opening to provide a diverging passage with at least one step between the openings to agitate the flow.