Cannula insertion mechanism

An insertion mechanism for a cannula includes a cannula housing, a displaceable cannula, at least one cannula holder, an insertion spring, a triggering element, and a safety device. The safety device, in a secured state, holds the triggering element in a blocked position against a force of the insertion spring and, in a released state, releases the triggering element such that the triggering element is movable into a release position by the force of said insertion energy store and the at least one cannula holder is able to move relative to the cannula housing, driven by the insertion energy store, so as to trigger or implement an insertion movement or insertion. To reach the released state, the safety mechanism is heatable by a heating element and softened and/or weakened with respect to its mechanical carrying or holding capacity, or severed or at least partially or completely melted.