| 摘要 |
1,189,592. Reciprocating pump. E . PFEIFFER. Jan.16, 1968 [Jan.17, 1967], No.2309/68. Heading F1A. In a hand actuated bucket piston dispensing pump the upper end 6b of the piston 6a is thin walled and flexible, allowing movement of the piston relative to the rod 5 so that it can separate from the valve head 4 on the pressure stroke. At the position of the piston at the end of its delivery stroke the cylinder is recessed at 1a so that the pressure collapses and the piston 6a reseats on the head 4. In the inoperative position the piston 6a engages a member 7 and so seals the air bleed port 10. |
