| 摘要 |
PCT No. PCT/EP90/00264 Sec. 371 Date Oct. 16, 1990 Sec. 102(e) Date Oct. 16, 1990 PCT Filed Feb. 17, 1990 PCT Pub. No. WO90/09936 PCT Pub. Date Sep. 7, 1990.A valve device useful for obtaining a predetermined and immediate appreciable initial rate of flow of aerosol from an aerosol container and a subsequent predetermined and small continuous rate of flow. The valve device contains a standard valve, which is crimped on the aerosol container, and a unidirectional valve, located within the aerosol container and connected on one side to the standard valve, the connecting element providing a passage from the unidirectional valve to the standard valve, and on the other side to a conduit connected to a plunger tube for access to the contents of the container. Within the body of the standard valve is a movable closure element having a spring which holds the valve closed. The valve may be opened by depressing the spring with an actuator located outside the container. A closure member is provided for acting on the actuator. The closure element of the unidirectional valve is a movable diaphragm which is held closed by a second spring. During the filling of the container, the unidirectional valve is held open by the pressure applied by fluid flowing through the opened standard valve, the passage, the unidirectional valve, the conduit, the plunger tube and into the container. After the container is filled, the unidirectional valve is held closed by both the second spring and the fluid under pressure in the container. When the standard valve is opened, a second passage formed by the connection of the standard valve to the unidirectional valve and the latter to the conduit, allows for a continuous flow of fluid from the container around the closed unidirectional valve and through the standard valve to the atmosphere.
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