US Patent 7425102 Fluid flow control valve/seal for fluid dispensers

A fluid flow control valve for use in a fluid applicator tip which is connectable onto an open end of a resiliently squeezable container. The valve includes a valve body defining a flow aperture formed centrally therethrough. A separate sealing ball is held in coaxial alignment and gravity biased seated against the flow aperture and oriented downstream of fluid flow through the flow aperture from the open end of the container. The valve is thus normally closed and opens or unseats automatically when at least partially inverted to permit fluid to flow through the fluid aperture when the container is held in at least a somewhat inverted orientation and squeezed to increase fluid pressure to open or unseat the sealing ball. The sealing ball automatically reseats when the container is righted and there is no substantial pressure within the container, preventing virtually all air from drying the fluid within the container.