Abstract

A coal mining technique is disclosed whereby the coal, which is to be removed from horizontal seams, is cut from the inside of the seam first, thereby allowing the earth around the seam to collapse behind the cutting blades. In one embodiment, a tunnel is bored into the seam from a front surface of the hill. The tunnel is constructed into a "U" shape such that both an entrance and an exit hole are laterally displaced along the front surface of a hill. A chain drive having rotating cutters spaced therealong is drawn through the tunnel by a motor located outside the tunnel. The motor provides continuous outward pressure on the chain, causing the blades to rotate, thereby cutting the coal from the inside back wall of the tunnel. Buckets mounted along the chain serve to remove the coal from the tunnel. When rotating blades are not used, cutters may be mounted on the outside of the buckets to chip the coal from the seam. As the chain assembly is drawn forward through the coal seam, the earth covering is free to fill the tunnel from the inside, thereby leaving the terrain untouched.