An injection device including a receiving device movable in an insertion movement relative to the injection device, a tensioning element, e.g. a spring, which bears on a part of the injection device, and a coupling element for coupling the receiving device to the spring such that, during an insertion movement of the receiving device the spring is tensioned. In some embodiments, the invention encompasses a method for preparing an injection device for dispensing a substance from an ampoule, wherein a discharging spring of the injection device is tensioned by introduction of the ampoule into the injection device.