Drive mechanism for an autoinjector

A drive mechanism for use with a medicament delivery device, comprising

• a plunger rod comprising a hollow plunger rod defining a cavity,
• a drive spring positioned inside the cavity and operably engaged with the plunger rod,
• an actuator comprising a holding member releasably engaged to the plunger rod for holding said plunger rod with said drive spring in a tensioned state,
• a rotator operably connected and movable relative to said actuator and configured to interact with said holding member for holding said holding member in engagement with the plunger rod,
• an activator operably connected to said rotator such that axial movement of the activator in a distal direction relative to the rotator and the actuator causes the rotator to first rotate relative to the actuator and then subsequently to move distally and axially relative to the actuator, wherein the rotation and the axial movement of the rotator relative to the actuator causes the actuator to release the holding member from the plunger rod.