Apparatus for loosening and/or breaking coal deposits, rocks, granular or lumpy material, or scrap

摘要

An apparatus for breaking coal or other mineral matter from a bed thereof which comprises a string filling a bore hole which can rise steeply in this bed. The string consists of alternating breaking units and connecting pipes each braking unit having a differential piston displaced solely by the action of air pressure so that breaking slots are unblocked to discharge compressed air built up in the string. The pistons are provided with check valves to permit filling of the string.