Reciprocating pump for pumping water or oil from underground reservoirs

摘要

The pump consists of a liquid riser (6) joining the discharge of the pump (4) to the liquid table and inserted into this table. A non-return valve (9) is fitted to the bottom end of the riser tube (6) which lets the liquid enter the tube but maintains a column of the liquid in it. A rod (7) carries several pistons (8), controlled by a reciprocating movement (C,D) to enable the column to rise. Each piston (8) is formed of an orifice support (81,82,83) solidly mounted to the rod (7) so it moves with it, and a membrane (86) forming a non-return valve which rests on the support (81,82,83) and which closes the piston orifice under the weight of the liquid column above it, or opens this orifice when the piston (8) descends in the riser tube (6).