JOINT OF DOWNHOLE MOTOR Russian patent published in 2003 - IPC

FIELD: drilling equipment, arrangements for kinematic linkage of rotor of screw downhole motor with output shaft of spindle. SUBSTANCE: joint includes union with shoulder inside and additional support mounted in unit and aimed at interaction between embracing surface of additional support and embraced surface made in shoulder of shaft. Embraced surface of shoulder of shaft and embracing surface of additional support as well as butt of shaft and bearing surface of insert interacting with butt of shaft come spherical with centers of spheres in crossing point of central axis of shaft and plane passing through centers hemispherical key socket of shaft. EFFECT: increased functional reliability and prolonged service life of joint of downhole motor. 3 cl, 2 dwg