GB2367809A — Metering valve with collapsible chamber

USPTO Abstract

A metering valve 1 for use in a pressurised container 4 has a valve body 2 and a flexible sleeve 18 overlaying the valve body 2 and defining a collapsible chamber 19. The valve body 2 has an internal chamber 5 and a channel 17 providing a flow path between the internal chamber 5 and the collapsible chamber 19. A valve stem 13 is slidable axially through the internal chamber 5. An outlet valve means consists of an outer seal 7 which allows fluid to flow from the internal chamber 5 in the open condition of the valve. An inner valve means comprises an inner seal 8 which admits fluid from the container to the internal chamber 5 in a closed condition of the valve. The inner and outer seals 7, 8 extend between the valve stem 13 and the valve body 2 and at least one of them is made from a thermoplastic elastomer. The sleeve member 18 further comprises an outer flange 20 which provides a gasket seal between the sleeve and the container body. When the valve is activated pressure from the propellant inside the container acts on the sleeve 18 and causes the chamber 19 to collapse, dispensing a metered amount of fluid.