Sanofi
Drive assembly for a drug delivery device and drug delivery device comprising a drive assembly

Abstract:

A drive assembly for a drug delivery device includes a spring member, a piston rod and a piston rod nut being engaged with the piston rod. The piston rod nut is configured to rotate and axially move during dose setting. The spring member is compressed when the piston rod nut is moved during the dose setting. The piston rod nut is rotationally fixed during dose dispensing.