摘要 |
The pump has a first pumping means (1) to be immersed into the liquid that is to be pumped, and a second means, driving pumping means (2), adapted to drive the first pumping means. The driving pumping means has a cylinder chamber (7) which, via a conduit, for instance a bendable hose (3), communicates with the first pumping means. The cylinder chamber (7) has two mutually displacable pistons (9, 12) which, when subjected to a predetermined mutual displacement, allows liquid to flow from the cylinder chamber (7) to a discharge outlet (6) on the pump. The outer piston (9) is sealed against the cylinder chamber (7), whereas the inner piston (12) seals against the outer piston (9) only via a circular edge (20) thereon. The lower pumping means (1) has a main piston (39) which can be urged downwardly by the pistons (9, 12) in the driving pumping means against the action of a spring (41). When the pressure from the pistons in the driving pumping means ceases, the main piston will, by means of said spring (41), urge liquid up through the hose (3) and the cylinder chamber (7) to the discharge outlet. |