Link 1, mounted on rod 3, and rim 2 rotate about fixed axis A. Link 1 can slide with rod 3 in cross-head 7 which, in turn, slides freely along spokes 4 of rim 2. Thus the mechanism permits, rotation with a certain eccentricity between the axes of rotation of link 1 and rim 2. Link 1 is centred by springs 5 and 6.
$1397$LG,C$