| 摘要 |
A foam dispensing apparatus (20) of the present invention includes a reservoir (12) containing a foamable liquid (14), with a closed headspace (16) above a surface of the liquid (14). The apparatus (20) also includes a source of a gas (20) disposed to impose a gas pressure higher than ambient atmospheric pressure into the closed headspace (16). There is a mixing chamber (22) having an inside diameter, an inlet and an outlet open to the ambient atmosphere with a flow restricter (28) having a plurality of the openings therein in gaseous communication with the closed-headspace (16). The flow restricter (28) is positioned at the inlet of the mixing chamber (22) and an elongate delivery tube with an open passageway therethrough that defines a longitudinal axis extending from the inlet of the mixing chamber (22) to below the surface of the foamable liquid (14) disposed so that an application of the gas having higher pressure than atmospheric pressure to the headspace (16) causes the foamable liquid (14) to flow through the tube past the flow restricter (28), to mix with the headspace gas having higher pressure than atmospheric pressure that flows from the openings in the flow restricter (28) and then to expand to atmospheric pressure in the mixing chamber (22) thereby to form a foam from the foamable liquid (14) and discharge the foam from the outlet. <IMAGE> |
