| 摘要 |
A discharge assembly for discharging a metered volume of a liquid held in a pressured container includes an elongate tubular housing, a valve stem having a body locating within the housing, a chamber provided within the body of the valve stem and having a liquid inlet, and a liquid discharge element moveable along the chamber from a liquid primed position to a liquid discharged position to effect discharge of the metered volume of liquid, wherein a second fluid transfer passageway is formed along the outside of the valve stem between the inlet of the housing and the first fluid transfer passageway, and a seal is provided for relative sliding movement onto a seat as the valve stem moves to close the second fluid transfer passageway to fluid flow. |
