Remaining parallelism: Sync even with high displacement

The Semiflex coupling transmits torque by means of two pairs of parallel links offset by 90°. They connect the input and output sides with the central plate. When the shafts are aligned, all three plates are also in an aligned position. When radial displacement occurs, the links of a group pivot in parallel and enable the central plate to deflect radially to the relevant extent. Since the coupling elements always remain parallel to each other, the same input and output angular speed without phase shift and consequently absolute sync is always guaranteed for the coupling system.

Figure: Drive plate (blue) connected to central plate by parallel pair of links 1; drive plate (green) connected to central plate by parallel pair of links 2

Radial displacement of the drive plate due to the force-free pivoting movement of the pair of links 1

Radial displacement of the output plate due to the force-free pivoting movement of link pair 2

Both pairs of links pivot; they always remain parallel to each other, which guarantees absolute sync regardless of the radial displacement extent.