A medicament delivery device includes a housing with a circle-segment-shaped compartment for a drive unit that moves at least one stopper in a medicament container and that includes a support wheel and central hub on which first and second parallel disks are fixedly attached and interconnected by an abutment cross-wall； spherical members between the abutment wall and adjacent the stopper； a clock spring within the hub with an outer end connected to the hub and an inner end connected to a one-direction-rotatable tubular hub coaxially arranged around a shaft fixedly attached to a housing part； and an activation member connected to the first disk by a hold-and-release mechanism. When the activation member is not depressed, the wheel and spring are held in a tensioned static state, and when the activation member is depressed, the spring and wheel are released and the spherical members are forced against the stopper.
