An injection device having parts, the relative movement of which causes the active substance to be injected. For this purpose, a receptacle, into and in which a carpule/syringe can be inserted and mounted, is retained in a housing, the receptacle can be moved by means of a carriage, and a plunger that applies a force to the piston/s of the carpule/syringe is movably retained in the receptacle. A traction rope which is deflected by means of a roll mounted on the carriage is provided for performing the pricking stroke, injection stroke, and retracting stroke. One end of the traction rope is connected to the receptacle while the other end thereof is connected to a tension spring that is retained on the housing. Mechanisms between the housing, the receptacle, the plunger, and the carriage control the reciprocal coupling thereof to the traction rope.