The lengths of the links comply with the conditions: E͞F=G͞H=K͞L, E͞G=F͞H and G͞K=K͞L. Pins A and D of link 1 and pins B and C of link 6 slide along fixed guides a and b. Links 1 and 6 are connected by a kinematic chain consisting of two parallel-crank linkages, EGHF and GKLH. Always complied with in the mechanism is the condition of proportionality of the intercepts indicated on axes Ox and Oy by points A, B, C and D. Thus O͞A/O͞B=O͞D/O͞C.
$744$LW,MO$