A SHIELDED NEEDLE CANNULA

The invention relates to an injection system or a needle assembly in which a needle cannula secured to an injection device is shielded by an axially movable needle shield. Should the needle cannula beexposed to a force above a predetermined value e.g. if a user drops the injection device onto a hard surface, a locking mechanism will automatically lock and block further movement of the axially movable needle shield and thus render the injection device unusable. 本发明涉及种注射系统或针组件，其中固定到注射装置上的针套管由可沿轴向活动的针护罩防护。如果针套管暴露于高于预定值的力，例如，如果使用者将注射装置掉落在硬表面上，则锁定机构将自动地锁定且阻止可沿轴向活动的针护罩的进步活动，并从而使注射装置不可用。