Drive mechanism of a drug delivery device

摘要

A drive mechanism of a drug delivery device is presented comprising of a piston rod extending in an axial direction to be operably engaged with a piston of a cartridge, the piston rod being adapted to exert distally directed pressure to the piston for expelling a liquid medicament from the cartridge. A housing component to accommodates the piston rod and has a guiding member extending in a lateral plane and being engaged with piston rod for guiding the same in axial direction relative to the housing component. At least one actuation lock is used to engage with the piston rod to inhibit a proximally directed movement of the piston rod relative to the housing component.

主权项

1. A drive mechanism of a drug delivery device, comprising:
a piston rod extending in an axial direction to be operably engaged with a piston of a cartridge, the piston rod being adapted to exert distally directed pressure to the piston for expelling a liquid medicament from the cartridge, a housing component to accommodate the piston rod and having a guiding member extending in a lateral plane and being engaged with the piston rod for guiding the piston rod in the axial direction relative to the housing component, wherein the piston rod comprises an outer thread, and the guiding member and the piston rod are threadedly engaged such that the piston rod is rotatably supported in the housing component, and at least one actuation lock to engage with the piston rod to inhibit a proximally directed movement of the piston rod relative to the housing component, wherein the piston rod further comprises at least one radially inwardly extending recess to mate with at least one radially inwardly extending stop element of the actuation lock, and wherein the guiding member comprises multiple stop elements arranged along the circumference of the piston rod.