Toothed chain transmission

A toothed chain transmission comprises a toothed chain for transmitting a force between a larger gearwheel and a smaller gearwheel, wherein the inside flanks (6) of a link plate (3) are profiled tooth chain so that it (from the outer edges (5) of the adjacent link plates 3 ) protrude outwardly, and wherein the tooth flanks configurations of the larger and of the smaller gear are formed by involute curves which are designed to A1 satisfy the expression = A2, wherein A1 is a pressure angle of the smaller gear, A2 and Ac is pressure angle of the larger gear is a pressure angle of the inside flanks (6) of teeth (4) of the link plates (3). With this arrangement, the chordal action of the silent chain is suppressed both on the side of the larger gear and on the side of the smaller gear, whereby vibration and noise are reduced, related to the chord-activity, and the driving performance and durability improved become.