CLAMPING DEVICE

PURPOSE:To enable the smallness of size to be attained, by providing a rod member, to which an arm member is secured, and a piston member, which internally turnably mounts one end part of the rod member through a turning mechanism, so that even a workpiece of complicated shape is effectively clamped. CONSTITUTION:A rod member 60, to which an arm member 90 is secured, and a piston member 58, which internally turnably mounts one end of said rod member 60 through a turning mechanism 59, are provided. And a clamping device holds a workpiece W by the arm member 90 by pressing the piston member 58 and the rod member 60 through a spring member 86 while detaches the arm member 90 from the workpiece W by displacing the piston member 58 by the action of compressed fluid or the like and turning the rod member 60 through this pressing force. Accordingly, the arm member 90 enables its stroke to be decreased as short as possible, in this way, the device enables even a workpiece of complicated shape to be effectively clamped further the size to be small reduced at a stroke.