The present invention is generally directed to an injection device for selecting and dispensing a number of user variable doses of a medicament. The injection device comprises a housing (10) having a longitudinal axis (I), a dose setting member (60； 80) rotatable relative to the housing (10) during dose setting, a drive member (40) which is rotationally constrained to the housing (10) in a first dose setting mode and which is rotatable relative to the housing (10) in a second dose dispensing mode, a locking element (100) which is permanently rotationally constrained to the housing (10) and movable relative to the housing (10) in a direction parallel to the longitudinal axis (I) between a first dose setting position and a second dose dispensing position, an actuation button (70) movable relative to the housing (10) in a direction parallel to the longitudinal axis (I) between a first dose setting position and a second dose dispensing position for switching the injection device between the first dose setting mode and the second dose dispensing mode, a ratchet (42, 120) for transmitting torque from the dose setting member (60) to the drive member (40) during dose dispensing and allowing relative rotational movement between the dose setting member (60) and the drive member (40) during dose setting, the ratchet (42, 120) comprising first ratchet features (43) rotationally constrained to the driver (40) and second ratchet features (121) rotationally constrained to the dose setting member (60), and a spring (130). The spring (130) biases the locking element (100) and the actuation button (70) into their first dose setting position and biases the first ratchet features (43) into engagement with the second ratchet features (121).本發明總體上涉及一種用於選擇和分配多個使用者可變藥劑劑量的注射裝置。該注射裝置包括：具有縱向軸線(I)的殼體(10)；在劑量設定期間能相對於殼體(10)轉動的劑量設定構件(60；80)；驅動構件(40)，在第一劑量設定模式中在旋轉上被約束於殼體(10)且在第二劑量分配模式中能相對於殼體(10)轉動；鎖定元件(100)，在旋轉上被永久約束於殼體(10)，且能在平行於縱向軸線(I)的方向上相對於殼體(10)在第一劑量設定位置和第二劑量分配位置之間移動；啟動按鈕(70)，能在平行於縱向軸線(I)
