OIL WELL PUMP Russian patent published in 2018 - IPC F04B47/00 

FIELD: machine building.

SUBSTANCE: invention relates to the field of mechanical engineering, in particular to vertical plunger pumps with self-acting valves for pumping highly viscous fluids containing mechanical impurities and gas, in particular to downhole sucker rod pumps for use in the oil industry. Pump comprises a cylinder with a suction valve in the form of a sleeve with the possibility of overlapping radial holes formed in the lower part of the cylinder, having a plunger with a discharge valve at the bottom, an intake filter. Plunger in the lower part is made of a smaller diameter to form an annular space between the cylinder and the plunger. Bushing is made in response to the annular space with the possibility of axial movement limited by stops. Bushing in the lower part is provided with a disk with a central through-hole, the diameter of which is bigger than the diameter of the discharge valve seat. Surface of the disc is made responsive to the end of the plunger. In the bottom of the cylinder is a central through hole, in which an additional suction valve is installed.

EFFECT: volume losses are reduced and the between-repair period is increased by preventing the accumulation of mechanical impurities in the lower part of the pump.

10 cl, 11 dwg