| 摘要 |
1,165,435. Rotary positive-displacement pumps. P. VULLIEZ. Oct. 5, 1967 [Oct. 6, 1966; Sept.29, 1967], No. 45466/67. Heading F1F. A rotary positive-displacement pump of the gyratory-piston type comprises a fixed body 10 defining an annular cavity 15 that contains a partannular piston, or movable member, 16 and an arcuate partition 11a between a suction passage 27 and a pair of delivery orifices furnished with non-return valves 31, 32, which orifices are controlled by the piston as it gyrates while being driven by mechanism including a rotatable shaft 26 and three crank-shafts 20 whose crank-pins 18 are lodged in bearings within the piston, eccentrics on the shaft 26 and the crank-shafts being synchronously coupled to one another by a member 24. A mass or weight 25 on the shaft 26 effects dynamic balancing. Bellows 23 enclose each of the crankshafts and parts associated therewith, and a semicylindrical member 19 pivotally connects one end of the piston to the body 10. The piston is rendered in sliding contact with the body 10 such that working fluid is displaced on its radially innermost and outermost sides when it gyrates. The member 24 and the shaft 26 may be dispensed with, the piston then being driven by one of the crank-shafts. In each of two other embodiments, Fig. 3 and Figs. 4 and 5 (not shown), the piston or movable member has the configuration of a spiral, the laterial walls of the cavity containing the piston being of generally similar shape. In another embodiment, Fig. 6, two pistons, or movable members 16a, 16b of spiral shape are provided, these members being driven in antiphase relationship with each other by respective crank-pins (18a, 18b, Fig. 7, not shown), on three crank-shafts 20, one of which is connected to external driving means. A common suction passage 27 communicates with two spaces between the pistons, a single discharge non-return 31 being provided adjacent the centres of the pistons. One of the pistons may be rendered fixed relative to the body 10. A further embodiment, Figs. 8 and 9 (not shown), is generally similar to that according to (Figs. 4 and 5,) the mechanism for driving the piston being basically similar to that shown in Figs. 1 and 2. It is indicated that the pump may be used as a vacuum-pump. |
