METERING SYSTEM AND METHODS FOR AEROSOL DELIVERY

摘要

An apparatus for determining the volume of a fluid, the apparatus comprising: a housing containing a first volume (V 1 ) and a second volume (V 2 ) , a printed circuit board (501b) disposed within the housing such that the printed circuit board defines the first volume; wherein the second volume (V 2 ) contains an air region and a fluid region; wherein the printed circuit board includes: an acoustic source (501b); a first microphone (502b) acoustically coupled to the first volume (V 0 ); and a second microphone (503) acoustically coupled to a second volume (V 1 ); and a processor configured to calculate a change in volume of the air region wherein the processor determines an amount of fluid output from the fluid region.