Mechanism for impact drilling machine with improved rocker pulley action

摘要

Impact mechanism (100) raises and drops the free end of a lifting rope at set intervals, driving an underground impact boring tool. The new mechanism is a rocker (4) pivoting about an axis (A) perpendicular to the rope. One either side of this axis, pulley axes (S,S') are set parallel, the impact rope being passed through the pulleys. To cause impact, a drive pivots the rocker cyclically between resting- and releasing positions. In the latter, the rope wraps more of the pulley circumferences than at rest. Also claimed is an impact drilling machine with the mechanism as described, on the free end of the impact rope, opposite the side of the drilling mast (2), or at its head. The lifting rope (5) also serves as the impact rope.