MEDICAL DELIVERY DEVICE

A medical delivery device (3) comprises a rod element having a stem with a longitudinal axis and a first thread arrangement, a dosage member (34) comprising a second thread arrangement and a chamber body, a dial unit (31), and a coupling structure coupling the dial unit (31) to the dosage member (34). The stem of the rod element extends into the chamber body of the dosage member (34). In a dosing status of the medical delivery device (3), the first thread arrangement of the rod element engages the second thread arrangement of the dosage member (34). Further, in the dosing status, the rod element is movable along its longitudinal axis relative to the dosage member (34) by the first thread arrangement of the rod element and the second thread arrangement of the dosage member (34) travelling along each other such that a volume of a dosage chamber in the interior of the chamber body of the dosage member (34) is varied. Still further, in the dosing status rotation of the dial unit (31) applies a torsional force to the dosage member (34) via the coupling structure, which torsional force rotates the dosage member (34) such that the second thread arrangement of the dosage member (34) and the first thread arrangement of the stem of the rod element travel along each other. The coupling structure has an overload protection mechanism (313, 314, 322, 324) configured to prevent that the torsional force applied by the dial unit (31) to the dosage member (34) exceeds a predefined threshold force.