| 摘要 |
A sprocket wheel 10 has a plurality of equi-spaced circumferential teeth 11, and a plurality of pockets 12 positioned between the teeth. A central circumferential groove 14 in the sprocket wheel 10 divides each of the teeth 11 into two parts. Each of the pockets 12 is shaped to engage with a link 13 of a drive chain, each of the pockets being formed partially by flanks 16 provided on each of the two parts of each of the pair of adjacent teeth 11 defining that pocket. The flanks 16 constitute chain link bearing faces, and each of the flanks has an inner end zone 18 adjacent to the groove 14, and an outer end zone 19 remote from the groove. <IMAGE> |
