The lengths of the links comply with the conditions: B͞M=1.46A͞B, E͞C=B͞C=0.77A͞B, F͞D=D͞M=D͞L=0.7A͞B, F͞E=1.46A͞B, A͞E=2A͞B and A͞F=1.54A͞B. Link 1 turns about fixed axis A and is connected by turning pair B to link 2. Link 2 is connected by turning pair C to link 3 which turns about fixed axis E. Link 4 is connected by turning pairs M and D to links 2 and 5. Link 5 turns about fixed axis F. When link 1 turns about axi s A, point L of link 4 describes a path of which a certain portion approximates a straight line.
$690$LW,GI$