PUMP Russian patent published in 2018 - IPC F04B47/00 F04B15/00 

FIELD: machine building.

SUBSTANCE: invention relates to the field of engineering, in particular to vertical plunger pumps, especially for pumping highly viscous liquids containing mechanical impurities and gas, in particular, to borehole sucker-rod pumps, and can be used in oil industry. Pump includes a housing made in form of glass with central hole at the bottom, a saddle, a cylinder with a narrowed neck and installed with the possibility of limited axial movement between the bottom of the glass and the saddle to form a suction valve. In housing between neck and saddle at least one through radial hole is made. Plunger with rods on the front and back sides is installed in the cylinder with formation of working cavity and control cavity. Reverse side of seat serves as a seat for discharge valve, which is mounted with possibility of limited axial movement along the stem, installed on plunger front side. Stem on the reverse side of the plunger is provided with a collar, made in form of ring, in response to stem and central hole, with the possibility of displacement along stem limited by the plunger and stem stop.

EFFECT: volume flow is increased by reducing delay in opening and closing suction valve and eliminating occurrence of excessively low pressure in rod cavity.

3 cl, 2 dwg