Drum 2 rotates about fixed axis B. Members 4, carrying knives 3, are connected by turning pairs A to drum 2. The speed of travel of stock 1 being sheared equals the peripheral speed of drum 2. Spring 5 holds knives 3 apart. The stock is sheared when members 4 pass between rollers 6 which force their diverging ends, holding the knives, together.
$537$SL,FD$