| 摘要 |
Hydraulic reciprocating pump for drawing liquid. The pump comprises a driving pump part 2 and a lowerable pump part 1 which intercommunicate via a line 3a. The line 3a communicates with a first pressure chamber 17 which is arranged in the lowered pump part 1 and surrounded by a tubular casing 21 which, between itself and the first pressure chamber 17, forms a second pressure chamber 22, and which, via a second line 3b which surrounds the first line 3a, is capable of communicating with a drawing-off point 6. The first pressure chamber 17 has an elastic wall 16 which can move relative to the tubular casing 21 as a result of pressure difference between the two pressure chambers. <IMAGE> |
