Patent ID: 8021133

Claim:
A feed pump with a variable-speed drive for metered dispensing of a controlled quantity of a feed fluid, wherein: said feed pump is constructed as a single-stage centrifugal pump comprising a radial wheel having a centrifugal structure arranged in an impeller chamber of a pump casing so as to be rotatable in order to convey a fluid between a pump inlet and a pump outlet; said radial wheel being connected to a variable speed drive motor, receiving a flow centrally, being provided with a plurality of feed ducts, and having an outside diameter (D LA ) of up to 50 mm; wherein said variable speed drive motor has a five digit range of rotational speed; and said feed pump being designed for partial-load operation at feed quantities ranging from 0 ml/min to 3600 ml/min and with lifts of 20 meters to 300 meters; said impeller chamber has an inside diameter (D LR1 ) which is at most 4% larger than the outside diameter (D LA ) of the radial wheel; a seal is arranged between the pump casing and one of a hub of the radial wheel and a drive shaft for the radial wheel; wherein the pump outlet is provided on the circumference of the impeller chamber, wherein the pump outlet is arranged substantially tangentially to the outside diameter (D LA ) of the radial wheel; the pump casing is provided with a heat regulating device, and fluid tight connections connect the heat regulating device to heat regulating media and connect the impeller chamber to a system into which fluid is dispensed by the feed pump.