| 摘要 |
<p>DISPENSING CLOSURE FOR A SQUEEZABLE CONTAINER A housing containing an annular tapered valve seat and mating valve secures the valve in fluid communication with the container interior. Fluid in the container under pressure displaces the valve from its seat, flows through the interface between the valve and seat and is discharged to the ambient through a fluid passage coupled to the interface. A shoulder in the housing engages a shoulder on the valve for limiting the displacement of the valve to a value sufficiently small to. retain fluid in the interface in the absence of pressure above ambient in the container. The fluid in the interface acts effectively as a seal to ambient air so that a negative pressure in the container results in ambient air pressure forcing the valve to its closed position.</p> |
