Automotive dosing pumps have been available on the market for more than 25 years now. Initially used for fuel fired heaters in mobile systems - trucks, passenger cars, e. g. -, this type of a reasonable dosing unit nowadays is applied in many fields. Based on the experience of delivering fuels of any kind, the dosing pump was further developed to deliver and dispense more or less any kind of liquid media. One of the most innovative operational areas of such compact metering units is the fuel cell reformer technology, wherein a constant flow of a certain amount of fuel is required. The availability of liquid fuels as a source of energy for producing electricity within a fuel cell is the basis for the success of such systems. Future fuels, e. g. bio-fuels, are environmentally-friendly fuel sources. Thus, components for supplying these liquid fuels are needed, and then adapted to the challenging needs of these special fuels or fuel blends. This type of an automotive pump combines the abilities of priming, delivering respectively metering of liquids, in one very compact unit, thus helping to optimize existent systems. The widely advanced integration of functions and abilities makes many components as sensors, shut-off valves and injectors dispensable. Dosing units have to continually deliver the exact amount of liquid during their lifetime. Hence, all pump designs were consequently tested in durability tests with different kinds of fuel, even biodiesel-fuels containing aggressive substances or gasoline-ethanol-blends. The global usage of metering units requires a robust design and robust materials as they are in direct contact to the fluids. Therefore these pumps have to be able to deliver all fuels that are commercially obtainable. Investigations have also been made to fulfil special demands for biomass fuels that potentially may degenerate. As they are designed as electromagnetically actuated piston pumps, the total flow rate is determined by the frequency of the piston's movement only, which is the basis for easy control to achieve the precise metering ability. Based on relevant test results, the interaction of dosing unit and the individual future fuels is taken into account.
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