RADIAL PISTON FLUID TRANSLATING DEVICE WITH POWER CONSERVING SCAVENGING MEANS

摘要

In a pump or fluid motor (11, 11a, 11b) having a closed chamber (57) in which cylinders (38) orbit and reciprocate, leakage and cooling fluid which accumulates in the chamber (57) is formed into a rotating annular volume by centrifugal effects and exhibits a higher pressure in the region where the cylinders (38) move radially inward and closer together than in the opposite region where the cylinders (38) move outward and further apart. Power wastage from drag torque, turbulence and heat generation is reduced by scavenging the accumulated fluid from the chamber (57). Internal recirculation of the scavenged fluid from the high pressure portion of the annular rotating volume back to the low pressure portion is avoided by communicating the drain passages (68, 68a, 68b) with only a limited relatively high pressure sector of the rotating volume of fluid.