The invention relates to a disposable injector with a housing (10), and with a trigger device (80) comprising an energy storage means (50), an actuation ram (60) and a trigger sleeve (90). The actuation ram (60) and the housing (10) have blocking surfaces (17, 72) which are directed towards each other and between which at least one displacement body can be arranged. The actuation ram (60) is pivotable about the longitudinal axis (5) of the disposable injector and comprises displacement segments (73), which are arranged offset in relation to the blocking surfaces, such that the displacement segments can be brought into contact with the displacement body. Moreover, by means of a movement of the trigger sleeve (90) in the direction of the longitudinal axis, a travel limit of the displacement body loaded by the displacement segment can be cancelled for releasing the energy storage means.
