A pneumatic-type precision annular workpiece inner positioning surface clamping device, wherein a rod portion of a piston assembly (5) is inserted into a central hole of the wedge-shaped block (12), and the piston portion of the piston assembly (5) is located in a closed chamber of a cylinder body (15); a disc spring (3) is sleeved on the piston assembly (5); an air intake hole (1-1) is provided in the lower plate (1), an air vent hole (15-1) is provided at the upper portion of the cylinder body (15); and an elastic hinge block (6) is sleeved outside the wedge-shaped block (12). The pneumatic-type precision annular workpiece inner positioning surface clamping device has a simple structure, high reliability and strong adaptability.

A clamping arrangement for fixing workpieces, having a housing with a clamping cone and a clamping segment ring with a plurality of clamping segments. The clamping segments are movable radially relative to one another via joint axial movement relative to the clamping cone. An ejector pin is provided for removal of the clamping segment ring from the clamping cone. A contact region for reception of or contact with a distal end of the ejector pin is provided on an end face of at least one of the clamping segments, which contact region is designed such that the ejector pin restricts outward mobility of the clamping segment in the radial direction in a positive locking manner when the distal end of the ejector pin is arranged in the contact region.

A clamping arrangement for fixing workpieces, having a housing with a clamping cone and a clamping segment ring with a plurality of clamping segments. The clamping segments are movable radially relative to one another via joint axial movement relative to the clamping cone. An ejector pin is provided for removal of the clamping segment ring from the clamping cone. A contact region for reception of or contact with a distal end of the ejector pin is provided on an end face of at least one of the clamping segments, which contact region is designed such that the ejector pin restricts outward mobility of the clamping segment in the radial direction in a positive locking manner when the distal end of the ejector pin is arranged in the contact region.

An expanding collet device can selectively clamp a workpiece to a workpiece support and can include an arbor, expandable collet and threaded screw actuator. The threaded screw actuator mechanism can include a support, drawbar, socket and a pair of thrust bearings. The drawbar can be connected to the collet and can extend into the support. An outer circumferential portion of the drawbar can oppose and be spaced away from an inner circumferential portion of the support. The socket can surround the drawbar and can include external threads engaging internal threads on the support such that rotation of the socket relative to the support displaces the socket in the axial direction. The socket, support, and drawbar can be configured such that rotation of the socket relative to the support displaces the drawbar in the axial direction such that the drawbar moves the collet between the released position the clamped position.