DEVICE FOR CHANGING THE WELLBORE PATH Russian patent published in 1994 - IPC

FIELD: well drilling. SUBSTANCE: device includes body made in form of hollow end cylinders rigidly connected by hollow shaft conjugated with spring-loaded piston having two stops, one of which is connected with inner surface of one of end cylinders, and the other, with inner surface of main bushing located between end cylinders for rotation when piston moves towards well bottom. Piston spring is installed in hollow of other end cylinder. Additional shaft is located inside shaft with central channel and installed in bearings of end cylinders and connected by gearing or universal joint with downhole motor and drilling bit. Cylindrical hollows and landing holes of end cylinders are made with eccentricity not exceeding half-difference of outer diameter of drilling bit and drill pipes. Landing holes of main bushing and end cylinders are made with same eccentricity. Main bushing is made in combination with one end cylinder movably installed on thrust bearing of shaft with central channel whose outer surface has longitudinal helical splines connected with rollers or spring-loaded by dowels attached to piston inner surface. Movable jacket is installed on outer surface of main bushing connected with piston by means of straight splines. EFFECT: higher efficiency. 6 cl, 10 dwg