When piston 1 is moved to the left by the action of fluid delivered to the right end of the cylinder, draw bolt 2 pulls crosspiece 6 downward. By means of pins a, this turns levers 3 about fixed axes A to locate and clamp workpiece 4 by its bore. When piston 1 is moved by fluid to the right, spring 5 raises crosspiece 6, retracting levers 3 and releasing the workpiece. Two levers 3 are conventionally shown. Actually, there are three levers equally spaced at 120° to one another.
$3884$LHP,GC$