Patent ID: 8038558

Claim:
Chain drive or return arrangement for chain-drawn winning or transport facilities, suitable for use with underground mining involving the use of plow winning systems or scraper chain conveyors, comprising: a sprocket; and a chain assembly returned or driven by the sprocket, wherein the chain assembly comprises: vertical chain links; and horizontal chain links, and wherein the sprocket comprises: a plurality of sprocket teeth arranged uniformly around its circumference; and chain link pockets between each pair of adjacent teeth, the pockets being delimited by tooth flanks of the sprocket teeth and configured for taking up a horizontal chain link of the chain assembly, wherein the horizontal chain links include bows that form a power transmission zone when the horizontal chain links engage in the chain link pockets of the sprocket, wherein the bows each include bow flanks linearly tapered towards each other in a first plane, the bow flanks being on opposite sides of a curved bow center section, wherein the bow flanks of the horizontal chain links have a concave trough in a second plane, the second plane being orthogonal to the first plane the concave trough being formed at least below an equatorial line, and wherein the tooth flanks delimiting the chain link pockets have a convex curved shape matching said bow flanks, at least in contact surfaces of the sprocket teeth with the horizontal chain links.