The present invention relates to an injection device (1) for automatic spring-loaded injection of liquid medicament that allows setting of individual dose sizes by a user, the injection device (1) defining an interior space A housing (3) having a longitudinal window (7), a rotatable dose dial (2) held axially against the housing (3), a rotation carrying a mark (6) indicating the size of the setting dose A rotatable scale drum (4) operatively connected to a dose dial (2) for rotation as the dose dial (2) is rotated to set the dose, , A sliding element (11) comprising a sliding window (12), which is adapted to slide axially with respect to the housing (3) during dose setting, through a sliding window (12) Carried by the scale drum (4) And the sliding element (11) in which the indicia (6) can be seen, so that the longitudinal window (7) and the sliding window (12) form a dose size display in combination with the indicia (6) , Wherein the scale drum (4) rotates in the internal space defined by the housing (3) during dose setting and the inner surface of the sliding element (11) is provided on the outer surface of the scale drum (4) Characterized in that it comprises an internal function (29) which engages an external thread (5) to be externally threaded, the sliding element (11) further comprising a sliding element (11) which, when the scale drum (4) The drive spring 14 is axially guided in the housing 3 so as to move, the drive spring 14 is attached to the scale drum 4 at one end and to the housing 3 at the other end so that the scale drum (4) and the housing (3) It is charged by the relative rotation, about the injection device.本発明は、使用者による個々の用量サイズの設定を可能にする液体薬物の自動ばね駆動注射のための注射デバイス（１）であって、該注射デバイス（１）は、内部空間を画成し長手方向窓（７）を有するハウジング（３）と、ハウジング（３）に対して軸方向に保持される回転可能用量ダイヤル（２）と、設定用量のサイズを示す印（６）を担持する回転可能スケールドラム（４）であって、用量ダイヤル（２）が回転されて用量が設定されるときに回転するように用量ダイヤル（２）に機能的に連結される、回転可能スケールドラム（４）と、摺動窓（１２）を備える摺動要素（１１）であって、用量設定中、ハウジング（３）に対して軸方向に摺動するように適用され、摺動窓（１２）を通して、スケールドラム（４）によって担持される印（６）を見ることができ
