| 摘要 |
<p>A sprocket wheel has a plurality of equi-spaced circumferential teeth, and a plurality of pockets positioned between the teeth. A central circumferential groove in the sprocket wheel divides each of the teeth into two parts. Each of the pockets is shaped to engage with a link of a drive chain, each of the pockets being formed partially by flanks provided on each of the two parts of each of the pair of adjacent teeth defining that pocket. The flanks constitute chain link bearing faces, and each of the flanks has at least three separate bearing surfaces.</p> |
