Abstract: A punch unit, in particular for making a punch for the binding comb of a ring binding is set-up of a circular shaped blade 1 and a counter die 19. The circular blade 1 is rotatably beard concerning an axis of rotation 27. At the circumference of the blade 1 cutting elements 2 are arranged. This cutting elements 2 raise over a fictive rolling circle 21. The surface of the counter die 19 is arranged perpendicular at the distance of the rolling circle radius rw, to the axis of rotation 27 of the circular blade 1 and show one or several opening in which in each case intervenes at least one cutting element 2 of the circular blade 1.

Abstract: A punch unit, in particular for making a punch for the binding comb of a ring binding is set-up of a circular shaped blade 1 and a counter die 19. The circular blade 1 is rotatably beard concerning an axis of rotation 27. At the circumference of the blade 1 cutting elements 2 are arranged. This cutting elements 2 raise over a fictive rolling circle 21. The surface of the counter die 19 is arranged perpendicular at the distance of the rolling circle radius rW to the axis of rotation 27 of the circular blade 1 and show one or several opening in which in each case intervenes at least one cutting element 2 of the circular blade 1.