Nut 1 is connected by a screw pair to stud a which is screwed tightly into the fixed link (base). Stud a passes with clearance through a hole in segment 2. Workpiece 3 is clamped by segment 2 when nut 1 is tightened. Spring 4 raises segment 2 when nut 1 is released.
$205$SL,GC$