Patent attributes
The present invention relates to a drive mechanism of a drug delivery device for setting and dispensing of a dose of a medicament, the drive mechanism comprising: a housing, a piston rod to operably engage with a piston of a cartridge to displace the piston in a distal direction, a rotatable member arranged on an axially extending axis of rotation in the housing, said rotatable member being rotatable in a dose incrementing direction against an action of a spring element and being operably engageable with the piston rod during the dispensing of the dose, and a clutch element comprising at least one radially displaceable clutch element to engage with a rim of the rotatable member with a variably adjustable strength.