VOLUMETRIC LOSSES OF A MULTI PISTON FLOATING CUP PUMP

摘要

The floating cup principle is a new axial piston concept for hydrostatic machines. Unlike slipper type and bent axis machines, the floating cup design features a double barrel configuration with two rings of pistons. The number of pistons is also much higher than that of conventional pumps and motors. Moreover each piston has a separate cup-like cylinder, which is floating on a rotating barrel plate. It is obvious that the floating cup principle has more leakage gaps than conventional axial piston pumps and motors. Nevertheless, measurements have already proven that the volumetric losses of the floating cup principle are not higher than of current axial piston principles. This paper describes the design aspects that are related to the control of the volumetric losses in the floating cup design, especially the leakage losses from the gaps between the pistons and the cups.