When piston 1 is moved to the right by the action of fluid delivered to the left end of the cylinder, sleeve 2, mounted rigidly on the end of the piston rod, turns levers 3 about fixed axes O. Levers 3 move jaws 4 outward from the centre by an equal amount. Thus, the jaws locate and clamp a workpiece by its bore. The workpiece is released when piston 1 is moved to the left by spring 5.
$3890$LHP,GC$