| 摘要 |
1,129,293. Reciprocating pumps and motors. NATIONAL RESEARCH DEVELOPMENT CORP. Feb. 2, 1966 [Feb. 11, 1965], No. 5898/65. Headings F1A and F1P. An auxiliary piston 8 for a rotary cylinder block or linear ball piston pump or motor comprises a substantially rigid disc having a partspherical face with a radius of curvature equal to the disc radius adapted to provide a seating for a ball piston 1. The piston 8 has a central aperture (10), Figs. 2 and 3 (not shown), and arcuate pockets (11, 12, 13) in its part-spherical face which communicate with the opposing face through respective bleed ports (14, 15, 16). The piston 8 may be formed of impregnated sintered metal or P. T. F. E. |
