Static dosing appliance, especially dosing or proportioning pump

摘要

A static dosing or proportioning appliance comprises a pair of vessels, electrically operated inlet valves and outlet valves, liquid-level sensors and controllers and/or regulators which ensure alternate filling of a first container, while liquid is discharged from the second container, which is then followed, while the second container is filled, by liquid being dispensed from the first container. The filling and discharge cycle of the containers is repeated until a preselected liquid volume, precisely dosed (metered), has been dispensed. During normal operation, both containers dispense the same total volume. If the required total volume of the dosed liquid comprises a fraction of the normal container volume, one container is provided with a fractional liquid level sensor which can be set to fill the container initially to the fractional volume and to start the dosing operation on the basis of this container being discharged.