| 摘要 |
A liquid dispensing apparatus is provided having a container for storing the liquid to be dispensed, an anti-drip valve cartridge connected to the container and a needle element connected to the valve cartridge. A device is provided for pressurizing the container for the duration of a time interval and for depressurizing the container to atmospheric pressure, simultaneously, with the end of the time interval. The valve cartridge has an outlet portion which sealably connects an outlet opening thereof in registry with the bore of the needle element. A pressure activated poppet valve can be provided in the valve cartridge to seal the outlet opening upon the depressurization of the container. After depressurization, a volume of liquid is left in the needle element which exerts a pressure at the end of the needle element that is less than the incoming atmospheric pressure. As a result, liquid will not drip from the end of the needle element after the depressurization of the container and thus the dispensing of the liquid. An air barrier can be provided in the container to prevent airation of the liquid to be dispensed. Additionally, a liquid induction fitting and a liquid storage tank can be provided for automatic refill of the container.
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