Patent ID: 8870831
Filing Date: 2014-10-28
Classification: A61M

Abstract:
1. A dose reset mechanism for a medicament delivery device having a housing having opposite distal and proximal ends and a medicament container, comprising: a dose setting member coaxially and rotationally arranged in the housing for setting a dose when it is rotated and for resetting the dose when it is rotated in an opposite direction, the dose setting member having a dose setting knob accessible outside the distal end of the housing; a drive member connected to a plunger rod to act on the container for expelling the medicament; a connection member arranged between the dose setting member and the drive member, wherein the connection member and the dose setting member are connected by an engagement mechanism, and the connection member and the drive member are connected by a ratchet mechanism such that the connection member rotates when the dose setting knob rotates for setting a dose and is prevented by the ratchet mechanism from moving in the opposite direction; and a drive spring having a first end connected to the connection member and a second end connected to a fixed point of the housing such that the drive spring is tensioned when the dose setting member and the connection member are rotated for setting a dose; wherein the dose setting member further has at least one dose reset member and at least one supporting element interactively connected to the ratchet mechanism such that the ratchet connection between the connection member and the drive member is released when the dose knob is turned in the opposite direction; and the at least one dose reset member comprises a first arm portion protruding generally transverse to an outer circumferential surface of the dose setting member, a second arm portion axially extending in a proximal direction, and the second arm portion includes a curved surface.