| 摘要 |
<p>A dispensing fitment for squeeze bottles includes a combined discharge and vent passage for establishing communication between the atmosphere and the interior of the bottle, the fitment defining a pair of oppositely facing, annular valve seats of different diameters, and further including an annular resilient diaphragm valve extending across the combined discharge and vent passage while being unattached to the fitment and normally being axially compressed against both valve seats for closing the passage. The valve is deflected to a discharge open position in which it is unseated from one of the valve seats when the pressure within the bottle exceeds atmospheric and the valve is deflected to a vent open position in which it is unseated from the other of the valve seats when the pressure within the bottle is reduced below atmospheric.</p> |
