Rotary pump or motor

Claim 1

IN A ROTARY HYDRAULIC MACHINE, GEAR TYPE IMPELLER MEANS, A HOUSING FOR SAID IMPELLER MEANS, TRANSVERSELY AND AXIALLY MOVABLE WEAR PLATE MEANS HAVING A FIRST SIDE MOVABLY BUTTING AGAINST A SIDE OF SAID IMPELLER MEANS AND A SECOND SIDE SPACED FROM AND FACING THE HOUSING, MEANS INCLUDING A FLUID PRESSURE CHAMBER AT THE SECOND SIDE OF SAID PLATE FOR EFFECTING MOVEMENT OF SAID WATER PLATE MEANS RELATIVE TO THE IMPELLER MEANS, MEANS INCLUDING RESILIENT SEALING MEANS AT THE SECOND SIDE OF SAID PLATE PROVIDING HIGH AND LOW PRESSURE AREAS AT THE SECOND SIDE OF THE PLATE, AND PASSAGE MEANS CONNECTING SAID HIGH AND LOW PRESSURE AREAS TO HIGH AND LOW PRESSURE REGIONS, RESPECTIVELY, OF SAID IMPELLER MEANS, THE PERIPHERY OF SAID WEAR PLATE MEANS BEING INSET FROM THE HOUSING SUBSTANTIALLY TO THE ROOTS OF THE GEARS FOR A CONSIDERABLE ANGULAR EXTENT IN THE HIGH PRESSURE AREA, WHEREBY THE PRESSURE IN SAID HIGH PRESSURE AREA BIASES THE WEAR PLATE TRANSVERSELY IN THE DIRECTION OF THE LOW PRESSURE ARA AND THE PERIPHERIES OF THE GEAR TEETH ARE OPENED TO THE HIGH PRESSURES TO PROVIDE RADIAL BALANCING OF PRESSURES ACTING ON THE GEARS AND REDUCTION IN DRIVING TORQUE.