RADIAL PISTON TYPE HYDRAULIC MOTOR

1,217,525. Radial cylinder hydraulic motors. ROLLS-ROYCE Ltd. April 5, 1968, No. 16381/68. Heading F1A. A radial cylinder hydraulic motor comprises a cylinder housing, two rows of cylinder bores in the housing, a central axially extending fluid flow and return passage, interconnecting passages communicating with the central passage and permitting substantially simultaneous flow of fluid to and from the two rows, and a valve member axially movable in the central passage to control flow to and return of fluid from the rows of bores. The cylinder housing 10 contains six rows 11-16 of radical cylinder bores 17, six bores in each row. The bores 17 of adjacent rows are staggered as shown in Fig. 2 to allow the axial spacing between rows to be reduced. Passages partly visible at 36 interconnect each bore 17 of row 11 with a corresponding bore of row 12 as indicated by arrows in Fig. 2. The bores in the remaining rows 13, 14 and 15, 16 are similarly interconnected. Ball pistons 18 co-operate with cam tracks 21-26 to cause rotation of a member 19. A distribution valve 28 driven from the member 19 through a splined connection at 40 can be moved axially to enable one pair 11, 12, two pairs 11, 12 and 13, 14 or all three pairs of rows of cylinder bores to be supplied with driving fluid.