Crank 1 rotates about fixed axis A and is connected by turning pair D to slider 5 which moves along slot a of link 2. Slotted link 2 rotates about fixed axis B and has extension b which is connected by turning pair E to slider 6. Slider 6 moves along slot d of slotted link 3 which turns about fixed axis C. Slotted link 3 is connected by turning pair F to connecting rod 7 which, in turn, is connected by turning pair G to slider 4. Slider 4 reciprocates along fixed guide f. When crank 1 rotates at uniform velocity about axis A, slotted link 2 rotates at nonuniform velocity, slotted link 3 oscillates and slider 4 travels with approximately uniform velocity over a part of its reciprocating motion.
$1458$LG,FD$