Patent ID: 9084852
Filing Date: 2015-07-21
Classification: A61M,Y10T

Abstract:
1. A piston rod assembly for a drug delivery device, comprising: a piston rod adapted to be operably engaged with a piston of a cartridge containing a medicament, at least one adjusting member displaceably disposed at the piston rod with respect to the piston rod's long axis, and being interconnected with a distal end section of the piston rod, and at least one interlock means adapted to interact with the adjusting member and with the piston rod for mutually locking in position the adjusting member and the piston rod in an arbitrary relative position and wherein the adjusting member and the piston rod are threadedly engaged in order to axially displace the piston rod and the adjusting member relative to each other, and wherein the interlock means is inhibits self-acting relative rotation between the piston rod and the adjusting member, wherein the interlock means comprise at least one resiliently biased tongue member adapted to engage with a corrugated outer surface portion of the adjusting member or of the piston rod.