| 摘要 |
1472169 Reciprocating pumps AEROSOL INVENTIONS & DEVELOPMENT SA 12 March 1976 [25 March 1975] 09917/76 Heading F1A A hand-actuated, container-mounted pump, e.g. for spraying cosmetics, comprises a bucket piston 24 which is wound downwardly by finger pressure to transfer liquid from a suction chamber 34 to a discharge chamber 35, the connection between the actuating member 21 and the piston being released at the end of the downward stroke and the upward discharge being effected by a spring 47 independently of the position of the actuating member 21, thereby ensuring an even discharge. In the embodiment shown, actuating member 21 has resilient fingers 27 engaging the top of a piston stem 23, the fingers being moved outwardly to release the stem when they engage a tapered projection 36. During the downward stroke, liquid passes from chamber 34 to chamber 35 via passage 43, valve 44, openings 45 and clearance between the lower end of stem 37 and piston 24. The container is vented via parts 17 and 49. In the embodiment of Figs. 4 to 6 (not shown), the actuator button (51) has a stem (56) passing into the piston (52) and engaging the piston with resilient fingers (55) at its lower end, the fingers being released from the piston by engagement with a tapered bore of the inlet valve seat (11). Flow between the suction and discharge chambers is controlled by a lip (59) of the piston engaging the stem (56). In the embodiment of Fig. 7 (not shown), a hinged actuating lever (60) has a cam portion (62) engaging a piston stem (61) for moving the piston downwardly until the stem enters a recess (63) in the lever, which permits free upward movement of the piston. |
