Pump for sea water desalination systems by reverse osmosis

A pump for sea water desalination systems by reverse osmosis;

• said pump being of the type baying two end chambers (2, 3) in which two pistons (4, 5) are housed, which describe alternative movements, alternatively pumping sea water towards a reverse osmosis membrane (7) of a desalination system, said desalination system moreover including a directional valve (9) activated by a pilot valve, the latter being activated by the displacement of the pistons (4, 5);
• comprising in that the body of the pump (1) has a centrally arranged third chamber (8) between the two end chambers (2, 3), provided with an external pressure intake (81), with two end mouths (82, 83) connected to the directional valve (9) and with an intermediate mouth (84) connected to a water outlet conduit (10a), being housed in said central chamber (8) a sliding block (11), laterally having a cavity (111) forming a closure with the wall of said third chamber (8);
• the sliding block (11) performing, according to its position, the alternative opening of the end mouths (82, 83) connected to the directional valve (9) and the interconnection by means of the lateral cavity (111) of the other two mouths (82, 84), (83, 84), simultaneously permitting pressure intake from the intermediate chamber (8) to the directional valve (9) and die guidance of water from the directional valve (9) to the water outlet conduit (10a).