Patent ID: 7867202
Filing Date: 2011-01-11
Classification: A61M,G01F

Abstract:
1. An injection device comprising an anti-rotation lock, comprising: a rod having an external face and a thread on the external face, at least part of the thread comprising individual teeth extending axially along a portion of the rod, wherein the individual teeth are formed such that a first tooth flank runs substantially vertically in a radial direction of the rod, and a second tooth flank is inclined in the radial direction relative to the first tooth flank; a housing part comprising a first rotation restricting element, which engages in a sliding movement with the second tooth flank of the teeth of the threaded rod to permit a rotating movement between the threaded rod and the housing part in one direction and the first rotation restricting element locks with the first tooth flank of the teeth and prevents rotation in the opposite direction, said first rotation restricting element comprising at least one catch element co-operable with said teeth; and a rotating sleeve mounted in the housing part, the rotating sleeve comprising a second rotation restriction element, which engages in a sliding movement with the second tooth flank of the teeth of the threaded rod to permit a rotating movement between the threaded rod and the rotating sleeve in one direction and the second rotation restricting element locks with the first tooth flank of the teeth and prevents rotation in the opposite direction, said second rotation restricting element comprising at least one catch element co-operable with said teeth; wherein the rotating sleeve rotates out of the housing part relative to the threaded rod, and the threaded rod is retained by the first rotation restricting element so that the threaded rod is prevented from rotating relative to the injection device housing; and wherein the rotating sleeve rotates into the housing part, and the second rotation restricting element engages with the threaded rod and restricts rotation of the rotating sleeve relative to the threaded rod such that the rotating sleeve slaves the threaded rod and rotates the threaded rod with it.