Dispensing method and apparatus utilizing a sensor to determine a time that a dispensing valve is open

摘要

Relatively small, fixed-volumes of liquid are measured and dispensed from a bulk container by empirically determining the liquid surface height and opening a dispensing valve for a time period that is calculated using a volume of liquid specified to be dispensed and the empirically-determined liquid surface height. The liquid surface height in the container is determined empirically for subsequent volumes of liquid that are dispensed. Dispensing accuracy is maintained whether the container is full or nearly empty.