The lengths of the links comply with the conditions: A͞D=B͞C and A͞B=D͞C. Rotation is transmitted between offset shafts A and D. Owing to the fact that there are three paired parallel-cranklinkages, there is no uncertainty of motion at the extreme positions (dead points). Disks 1 and 2 have three pairs of freely rotating rollers a and b. The sum of the radii of the rollers equals A͞D. Shafts A and D have equal angular velocity.
$797$LW,C$