US Patent 9132235 Medicament delivery device

A medicament delivery device includes a housing arranged to receive a medicament container, a drive unit arranged to act on a stopper in the medicament container, which drive unit includes a torsion drive spring. A dose setting member is operably connected to the drive unit such that a manual turning of the dose setting member causes a tensioning of the torsion drive spring. The device also includes an activation mechanism having an activation button protruding through a distal end of the device. The activation mechanism is operably connected to the drive unit such that actuation of the activation mechanism causes a release of the drive unit, with a set dose of medicament delivered.