Tool system with interchangeable tool inserts for punching machines

A tool upper portion comprising:

• a stamp shaft comprising, around a first central axis of the stamp shaft, a first circular cylindrical counterbore at a first side of the stamp shaft and an additional second cylindrical counterbore and a stamp shaft through-hole having an above lying third cylindrical counterbore in the direction of the first central axis of the stamp shaft above the first circular cylindrical counterbore;
• a stamp adapter comprising a first central axis of the stamp adapter extending through a center of the stamp shaft;
• a mounting device on the stamp adapter for accommodating the stamp shaft;
• wherein the mounting device comprises a central thread around the first central axis of the stamp adapter to connect with the stamp shaft using a first screw;
• and
• at least one interchangeable tool insert,
• wherein the stamp shaft and the stamp adapter are constructed to form a rotation lock when engaged with one another, wherein the rotation lock comprises
• a monolithic elevation extending from a first side of the stamp adapter, and
• at least one recess defined in the first side of the stamp shaft, wherein each of the at least one recess is configured to engage the monolithic elevation,
• wherein the first side of the stamp adapter is arranged to face the first side of the stamp shaft when the monolithic elevation engages one of the at least one recess,
• wherein the at least one interchangeable tool insert can be eccentrically received and fixed at the stamp shaft, and
• wherein the stamp adapter comprises a first stamp adapter through-hole to receive a second screw for screwing on the interchangeable tool insert.