AIR-OPERATED REVERSIBLE PERCUSSION TOOL TO DRILL HOLES IN GROUND Russian patent published in 2000 - IPC

FIELD: construction and mining equipment. SUBSTANCE: air-operated reversible percussion tool to drill holes in ground has mobile striker located in cylindrical body with windows and space housing stepped branch pipe with longitudinal conduit, means fastening branch pipe to cylindrical body, limiter of turn of branch pipe. In accord with invention limiter of turn of branch pipe has spring- loaded fixing arm mounted in means fastening branch pipe for contact with two main flats made in step of smaller diameter of branch pipe that are displaced one relative to another along longitudinal axis of stepped branch pipe by distance corresponding to movement of striker under conditions of forward and backward strokes of percussion tool. EFFECT: enhanced operational reliability of tool thanks to diminished probability of self-reversing as additional torque should be applied to it. 7 cl, 14 dwg