Volumetric metering device

A system for metering and dispensing a liquid product, comprising:

• a metering device comprising:
• a substantially cylindrical receptacle defining a cavity and including an inlet end having an inlet aperture and an outlet end having an outlet aperture;
• and
• a slug sized to fit within the cavity in a first position at the inlet end of the receptacle and sized to create a first known volume within the cavity equivalent to a desired amount of a liquid product to be dispensed, the slug further sized to move within the cavity from the first position to a second position at the outlet end of the receptacle upon application of a vacuum to the outlet aperture and dispensation of the first known volume of the liquid product from the cavity via the outlet aperture,
• wherein a second known volume of the liquid product substantially equivalent to the first known volume of the liquid product is drawn into the cavity via the inlet aperture as the first known volume of the liquid product is dispensed and the slug moves toward the outlet end of the receptacle;
• the slug further including at least one product bypass sized to permit the second known volume of the liquid product to flow toward the outlet end of the receptacle such that the slug moves from the second position through the second known volume of the liquid product and returns to the first position at the inlet end of the receptacle when application of the vacuum to the outlet aperture is removed;
• a venturi pump connected to receive the liquid product through the outlet aperture and by which the vacuum at the outlet aperture is generated when water flows through the venturi pump;
• and
• a product container from which additional liquid product is drawn into the cavity via the inlet aperture as the first known volume of liquid product is dispensed.