Device for clamping a workpiece to be machined

A device (1) for clamping a workpiece (2) to be machined, the device comprising:

• a chuck body (3) and a drive (5) fastened thereto, and
• at least one clamping jaw (6), which is coupled to the drive (5) in a drivable arrangement either directly or via intermediate elements (7) and which is or are held movably in or on the chuck body (3) in the direction of the workpiece (2),
• characterised in that,
• a free space (11) is provided between the chuck body (3) and a clamping jaw carrier (9) which accommodates the respective clamping jaw (6),
• an elastically deformable sleeve (12) is inserted in the free space (11), which sleeve (12) rests on the outside (8) of the chuck body (3) at two positions (21) spaced apart from one another, and
• a pressure chamber (14) is created between the chuck body (3), the sleeve (12) and their two support positions (21), into which pressure chamber a medium (16) can be filled, by means of which a pressure force directed outwards acts on the wall (W2) of the sleeve (12) and bulges it out in the direction of the clamping jaw carrier (9) between the support positions (21).