Patent ID: 9687608
Date: 2017-06-27
CPC Classifications: A61K,A61M,F16K,Y10T

Claim:
1. A pen-type drug injection device comprising: a housing having a longitudinal axis and a recess having an inner diameter at a distal end and defined by a side wall comprising a protrusion positioned parallel to the longitudinal axis such that it extends longitudinally and projects radially outward from the side wall, where the protrusion is deformable from a non-deformed shape to a deformed shape, where the non-deformed shape has longitudinal profile defined by a radial distance (R) measured relative to the side wall and perpendicular to the longitudinal axis; a cartridge having an outer lateral surface defining a hollow cylinder having an outer diameter at a proximal end that is smaller than the inner diameter such that there a slack between the side wall and the outer lateral surface when the hollow cylinder is inserted into the recess, where the protrusion is positioned longitudinally along the side wall such that further insertion of the hollow cylinder into the recess results in the deformed shape of the protrusion eliminating the slack and forming a press fit engagement between the recess and the outer lateral surface; and a cartridge holder retaining the cartridge within the cartridge holder, where a proximal end of the cartridge holder is connectable to the distal end of the housing, wherein the hollow cylinder is mechanically coupled within the recess by a force fit contact with a section of the longitudinal profile of the non-deformed shape to transform the protrusion to the deformed shape such that R is decreased in the section of the longitudinal profile that is in the force fit contact with the hollow cylinder, where a friction force is caused by a deformation of the protrusion when the hollow cylinder is coupled to the housing.