Displacement mechanism for mine roof support air pipes - has housing of displacement ram firmly coupled to hoist ram housing, with both rams guided by cams in support head duct

摘要

A hydraulic strut for supporting the roof of an underground working in a mine also supports an air discharge pipe (12). The pipe is suspended by a cable (13) which passes over a pulley mounted on the end of the body of a first hydraulic cylinder. A second hydraulic cylinder is mounted on the body of the first hydraulic cylinder, and the end of the cable is attached to the piston rod of the second hydraulic cylinder. The piston rod of the first hydraulic cylinder is fixed to the strut frame. When the first hydraulic cylinder is actuated, the discharge pipe is moved horizontally, whilst actuation of the second hydraulic cylinder moves the pipe vertically. ADVANTAGE - Compact, air pipe displacement design, with wider field of application.