An apparatus to make a certain volume of liquid available for atomization
comprises a container adapted to hold a liquid, and a piston pump. The
piston pump comprises a piston member and a valve body, with the piston
member being slidable within the valve body. Further, the valve body
functions with the piston member to define a metering chamber. In this
way, the metering chamber is adapted to be filled with liquid from the
container when the piston member is moved to a filling position, and the
piston pump is adapted to dispense a known volume of the liquid from the
metering chamber when the piston member is moved to a dispensing position.
