Link 3 carries gear segment a-a whose centre coincides with point C. Segment a-a meshes with gear rack b-b of link 4. When crank 1 rotates at uniform velocity about fixed axis A, the time ratio of the forward to the return stroke of link 4 is k=(π-arccos(A͞B/A͞C))/(arccos(A͞B/A͞C)).
$1742$GL,5L$