SUBMERSIBLE DISPLACEMENT PUMP Russian patent published in 2017 - IPC F04B47/08 

FIELD: engines and pumps.

SUBSTANCE: pump comprises a submersible motor, a driven oil pump, a normal piston pump with suction and delivery valves. The normal pump is rigidly connected via a rod with a piston hydraulic motor. Cavities of the hydraulic motor are connected via an automatic reversible valve to the suction and delivery lines of the driven oil pump. There is a safety valve, a compensation unit which head end is connected with the output of the normal pump, an oil tank with a fine oil filter and a compensator of oil cubic expansion mounted on the last one. The motor includes a protector, via the protector shaft the motor shaft is kinematically connected with the shaft of the driven oil pump. There is a filtration unit which does not exceed the dimensions of the submersible displacement pump diametrically, mounted outside of the normal pump housing with a clearance from the normal pump housing. The pistons of the normal pump are made in diameter smaller than the diameter of the hydraulic piston. The normal pump housing is made in diameter smaller than the diameter of the compensation unit housing and hydraulic motor housing.

EFFECT: invention will allow to improve the operational characteristics and reliability of the equipment.

6 cl, 1 dwg