Link 2 with lug a is connected by turning pairs B and E to crank 1 of four-bar linkage ABCD and to link 3 which, in turn, is connected by turning pair F to rocker arm 4. When crank 1 rotates about fixed axis A, points of lug a of the kneader describe complex connecting-rod curves that are used for the kneading process.
$884$LW,FD$