Multistage gear pump

摘要

A multistage gear pump for pressurizing fluid includes a housing, a drive shaft and a gear assembly. The drive shaft is rotatably supported in the housing. The gear assembly is disposed in the housing. The gear assembly includes at least first and second gear trains. Each train has a pair of drive and driven gears that are engaged with each other. The drive gear is provided on the drive shaft and followed by the driven gear. The first gear train and the second gear train are arranged so that fluid sequentially passes therethrough as the drive shaft rotates. A theoretical discharge capacity of the first gear train is larger than that of the second gear train. <IMAGE>