A kind of injection device, including a shell, shell limit central axis. Drive system defines an initial position and one-stroke ultimate position relative to shell. Axial motion drive system discharge medicine is from cylindrantherae. Spring mechanism includes operationally the first and second spring members with drive system. When transmission system is in the commanded stroke position that a people embraces, and the first spring members are mobile, second spring component is completed relative to trigger architecture from first position to the second position when Fluid pressure reduces drug and injects. When second spring element is moved to the second position and drives the stroke position of end, trigger architecture drives second spring part, indicates that injection is completed to this to generate tactile and/or earcon.
