Clamping device

A clamping system omprising:

• a rotationally driven work spindle (6);
• a first automatically activated clamping device (57) integrated in the work spindle (6);
• the device containing several pincer elements (33) which are concentrically arranged around a central axis (32) within the receiving part (1) and are impinged upon by a tension spring (39) so as to be moved into a clamping position in order to brace the tool (3) or the tool fixture, wherein the pincer elements (33) are coordinated with an axially movable closing element (17), which, in a forward position that is advanced in a direction of the pincer elements (33), pushes the pincer elements (33) for mounting purposes in their clamping position, which is swiveled inwardly by the tension spring (39), and which can move into a retracted position by a loosening mechanism (12, 16, 45, 46, 47) in order to release the pincer elements (33);
• a tool-changing head (58) removably arranged in the work spindle (6) and removably secured by the first automatically activated clamping device (57);
• and
• a second automatically activated clamping device (59) integrated in the tool-changing head (58), the second automatically activated clamping device (59) constructed as the first automatically activated clamping device (57).