US Patent 8215519 Fluid dispensing valve

A fluid dispensing valve is described which includes a valve housing having a wall which defines an internal cavity, and wherein a passageway is formed through the wall of the valve housing; and a valve control element having a continuous and deformable sidewall is coaxially and rotatably received within the internal cavity of the valve housing, and wherein at least a portion of the sidewall of the valve control element deforms when a vacuum is created in the internal cavity of the valve housing so as facilitate the controllable delivery of a source of fluid into the valve housing.