The invention relates to a disposable injector with a housing in which or on which are arranged, in each case at least in some areas, at least one mechanical spring energy reservoir, at least one cylinder/piston unit that can be filled at least temporarily with active substance, at least one piston-actuating ram and at least one trigger unit, in which the spring energy reservoir comprises at least one pretensioned spring element, in which at least part of the piston-actuating ram is positioned between the spring energy reservoir and the piston of the cylinder/piston unit, and in which the spring-loaded piston-actuating ram has at least one tension bar which is transversely movable at least in some areas and which, by means of a support portion, supports the tensioned spring energy reservoir on at least one bearing surface of the housing.
DE 36 44 984 A1 discloses an automatic injection device which is equipped with an injection needle and in which the injection needle is driven out by means of a mechanical spring reservoir and, at the same time, the injectable substance stored in the device is discharged. The spring element pretensioned in the spring reservoir is held in the housing of the injection device in the above-described manner. However, the tension bar is secured by means of a button-shaped catch element that is to be removed separately counter to the triggering direction.
The object of present invention is providing a disposable injector of modular design which, with a small overall size, comprises only a small number of components and, while being easy to handle, ensures safe storage and reliable operation.