DRIVE MECHANISM OF A DRUG DELIVERY DEVICE

摘要

The present invention relates to adrive mechanism of a drug delivery device for setting and dispensing of a dose of a medicament, the mechanism comprising: a housing (20), a piston rod (120) to operably engage with a piston (14) of a cartridge (12) to displace the piston (14) in a distal direction (1), a rotatable member (80) arranged on an axially extending axis of rotation (4) in the housing (20), said rotatable member (80) being rotatable in a dose incrementing direction (5) against the action of a spring element (78) and being operably engageable with the piston rod (120) during dose dispensing, a clutch member (150) comprising at least one radially displaceable clutch element (153) to engage with a rim (82) of the rotatable member (80) with variably adjustable strength.