Patent ID: 6173908
Filing Date: 2001-01-16
Classification: B05B,Y10S

Abstract:
A foam generating nozzle assembly (10), comprising a cylindrical housing (12) having an inner diameter, a first inlet (14) at a first end of the housing connected to a supply of foamable liquid under pressure, a second inlet (16) at the first end for providing an air supply area, a foam discharge outlet (20) at the other end of the housing, a conical screen (22) of a non-corrosive material providing a foam-forming surface and being disposed in said housing between the ends, the screen having a base and an apex with the apex directed toward the discharge outlet and the base touching the inner diameter of the housing, to provide a screen surface area larger than the inlet supply area, and a diffuser (19) associated with the first inlet (14) for spraying the foamable liquid onto the screen (22) in a conical spray pattern, and means associated with the diffuser (19) for adjusting the conical spray pattern to strike the screen adjacent to the base, wherein the foamable liquid is supplied at a flow rate of about 1 US gallon/minute/inch.sup.2 of screen surface area, at a pressure of about 70 psi, and wherein the foam produced is of an expansion ratio of 15-30:1, such that in operation the foamable liquid is sprayed onto the screen (22) while air is dragged through the screen (22) thereby generating the foam on the screen surface (22).