The lengths of the links comply with the conditions: A͞B=C͞D and B͞C=A͞D. Figure ABCD is a crossed-crank linkage. Slotted link 2, turning about fixed axis F, is connected by a sliding pair to slider 3 which, in turn, is connected by turning pair E to connecting rod 4 of crossed- crank linkage ABCD. Point E of connecting rod 4 describes connecting-rod curve a-a. When crank 1 rotates about fixed axis A, slotted link 2 rotates about fixed axis F with a short dwell when point E of slider 3 reaches the upper point of its path a-a. Links 1 and 5 have stops b to enable the mechanism to pass through its extreme positions (dead centres).
$1345$LG,D$