SCREW DOWNHOLE MOTOR Russian patent published in 2009 - IPC E21B4/02 

FIELD: oil and gas production.

SUBSTANCE: invention is related to drilling equipment, in particular to downhole motors for drilling of oil and gas wells. Screw downhole motor comprises stator with internal screw teeth, eccentrically arranged rotor with external screw teeth, spindle comprising radial bearing, spindle shaft and body, driving shaft for kinematic connection of rotor to spindle shaft, and also axial support rolling unit, including races with conical surfaces, roller with toroidal surfaces. Axial support rolling unit is made in the form of planetary axial support made of race arranged in upper part of stator coaxially to internal screw teeth, and rollers fixed on upper edge of rotor coaxially to external screw teeth with eccentric displacement relative to race, equal to eccentricity of gear engagement "rotor-stator". Race is made with cone surface at each end in the form of protruding truncated cones, tops of which are inverted to each other. Rollers have protruding working surfaces in the form of ball belts that interact with according cone surfaces of race. Rollers, limiting axial displacement of rotor, preserve possibility of roller running in internal screw teeth of stator.

EFFECT: reduced axial and radial loads at working elements "rotor-stator", prevention of preliminary wear and damage of stator and support units, increased reliability and durability.

4 cl, 3 dwg