| 摘要 |
<p>A piston for use in a coupling for a liquid product packaging and dispensing assembly in which liquid is pumped from a container via the coupling through a tube to the point of use. Such a coupling comprises a first interconnectable member with a hollow post and a biased sleeve closing openings in the hollow post and a second interconnectable member with a hollow sheath and a biased piston closing an opening at the end of the sheath. The parts are configured so that, upon connection, the post unseats the piston while the sheath displaces the sleeve, thereby allowing liquid flow. The piston is gas permeable and liquid impermeable. It and the post are configured such that, upon connection, any fluid residing between them is displaced. <IMAGE></p> |
