VALVE PLATE FOR AN HYDRAULIC PUMP OR MOTOR

1,211,343. Hydraulic reciprocating pumps and motors. JOSEPH LUCAS (INDUSTRIES) Ltd. Feb. 9, 1968 [Nov. 24, 1966], No. 52640/66. Heading F1A. The valve plate of a swash-plate or radial piston pump or motor comprises two parts 10a, 10b with kidney ports formed by aligned apertures 11, 12 and 13, 14 of different sizes, the recesses defined in part 10b by the overlap of the different sized apertures accommodating resilient compressible seal assemblies 15, 16 which engage the pump or motor housing Fig. 1 (not shown). The valve plate is held against rotation by dowels passing through holes in the valve plate, Fig. 4 (not shown). Pressure balancing of the valve plate relative to the cylinder block and housing is provided by seal assemblies 15, 16 and pressure balancing between parts 10a and 10b of the valve plate is provided by recesses in part 10a facing part 10b and connected sequentially to the working cylinders by ports in the valve plate face, sealing assemblies being provided in the recesses, Fig. 4 (not shown).