1, rotation angle range is different. The crank can rotate 360 degrees, and the rocker can only swing less than 180 degrees on both sides. The difference is that the rotation angle range is different.

2. Features. The two connecting rods of the double rocker mechanism can't rotate all around, and the three movable members all do variable-speed motion, which is only used for low-speed transmission mechanisms. The crank is the driving part, rotating at the same speed, the rocker is the driven part with variable speed reciprocating motion, and the connecting rod does plane compound motion. In the crank-rocker mechanism, the rocker is also used as the driving component, and the reciprocating swing of the rocker is converted into the rotation of the crank.