Fetch and Carry chain drive

Fig. 118 "Fetch and Carry" chain drive
A means of reducing backlash in chain drives, where the chain and sprockets are duplicated. One sprocket has each part adjustable relative to the other, by which each chain may be adjusted so that one leg is in tension for one chain, and vice versa. In this way there's no backlash or hysteresis on reversing the drive.
Scans from 'The Book of the Motor Car', Rankin Kennedy C.E., 1912

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