BORING RIG Russian patent published in 2007 - IPC E21B3/00 E21B19/84 

FIELD: mining, particularly boring rigs adapted to drill blast-holes during mine boring and lining.

SUBSTANCE: boring rig comprises rotator movably installed on guiding frame and provided with feed drive including friction pulley and flexible member passing over the pulley. The flexible member is connected to tightening device and is made as working and idle threads enclosing friction pulley. The friction pulley includes parts having different diameters. Working thread passes over pulley part having smaller diameter in one winding direction. Idle thread encloses pulley part having greater diameter in opposite winding direction. Some ends of working and idle threads are fastened to frame, other ones are connected to tightening device and may be alternately tightened.

EFFECT: increased efficiency of drilling operations due to provision of forced rotator movement in initial position after backward drilling operation.

3 cl, 1 dwg