An infusion device includes a stationary structure (2) including a first gear member (14), a drug container (11), and means (6, for extruding a liquid drug from the drug container (11) for injection into a patient. 7, 8, 12), and a dynamic structure (3) including a second gear member engaged with the first gear member, and the first gear member and the second gear member (13, 14). One (14) is driven, and the dynamic structure (3) is moved along the predetermined direction (D) by the engagement between the first gear member (13) and the second gear member (14). Driving means (4) for movement relative to the stationary structure (2) and engagement between the first gear member (13) and the second gear member (14) in the normal state of the injection device When the injection device receives an impact along a predetermined direction (D), the first gear member (13) and the second gear member (1 ) And a clutch means which make it possible to separate (23,25,28) a. [Selection] Figure 1注入装置が、第１のギア部材（１４）を含む静止構造体（２）と、薬剤容器（１１）、患者に注入するために薬剤容器（１１）から液状薬剤を押し出すための手段（６、７、８、１２）、及び第１のギア部材と係合した第２のギア部材を含む動的構造体（３）と、第１のギア部材及び第２のギア部材（１３、１４）の一方（１４）を駆動させ、第１のギア部材（１３）と第２のギア部材（１４）との間の係合により、動的構造体（３）を所定の方向（Ｄ）に沿って静止構造体（２）に対して動かすための駆動手段（４）と、注入装置の正常な状態において、第１のギア部材（１３）と第２のギア部材（１４）との間の係合を、は維持し、注入装置が所定の方向（Ｄ）に沿った衝撃を受けると、第１のギア部材（１３）及び第２のギア部材（１４）を分離することを可能にするクラッチ手段（２３、２５、２８）とを含む。【選択図】図１
