Low noise chain drive

Abstract

A low noise chain drive of this invention includes toothed sprockets and an endless silent chain having sets of link plates successively connected for articulation by means of connecting members. Each set has a plurality of transversely aligned link plates with each having a pair of link plate teeth designed to engage the sprocket and a pair of openings through which the connecting members are inserted. The link plate teeth are defined by an outside flank and an inside flank. The sprocket has sprocket teeth defined by a sprocket tooth flank. The sprocket tooth flanks and the outside flanks are profiled such that the outside flanks have a swelling located between the tip of the link plate tooth and a point that is in contact with the sprocket tooth after the completion of the engagement. The swellings are formed such that when one link plate set rotates around a rotational axis relative to the preceding set having completed the engagement with the sprocket, the swellings of the one link plate set project outwardly from a circle defined by the minimum radius centering on the rotational axis and osculating the sprocket tooth flank to be meshed with the outside flank located on the trailing side of the one link plate set. The link plate teeth stay in sliding contact at their outside flanks with the sprocket teeth from the beginning of their engaging process through its completion to thereby ease engagement impacts and noises.