Patent attributes
The present invention relates to a pump device with a first diaphragm pump head having two or an integral multiple of two fluid delivery chambers and diaphragms associated therewith, which are hydraulically coupled to a second diaphragm pump head. The second diaphragm pump head has two additional fluid delivery chambers and additional membranes associated therewith, which are drivable by a double-acting piston via associated diaphragm control chambers, a refilling valve being connected in each case to the diaphragm control chambers and the diaphragm control chambers being temporarily impinged with a diaphragm control pressure, which is greater than atmospheric pressure, using the refilling valve. The piston may thus be activated using a relatively small force to achieve a delivery action.