The lengths of the links comply with the conditions: D͞E=1.2B͞E, C͞D= 1.07B͞E, A͞F=0.44B͞E, G͞F=1.4B͞E, G͞B=1.22B͞E, G͞C=1.75B͞E, B͞C=0.59B͞E, A͞D=1.02B͞E and A͞E=0.89B͞E. Link 4 is connected by turning pair F to rocker arm 5, which oscillates about fixed axis G, and by turning pair A to connecting rod 2 of four-bar drag-link linkage BEDC. Crank 3 is designed as a collar that encircles fixed round disk 6 having its centre at point B. Point A of connecting rod 2 describes curve a-a which is self- intersecting at point H. Portion q-q of this curve, indicated by a heavy continuous line, approximates a circular arc of a radius equal to length F͞A of link 4, and with its centre at point F. When point A travels along portion q-q of its path, rocker arm 5 is almost stationary, i.e. it practically has a dwell. One revolution of cranks 1 and 3 corresponds to two full oscillations (back and forth) of rocker arm 5 through the angles ψ₁ and ψ₂ with a single dwell at the extreme right-hand position.
$751$LW,D$