Patent ID: 8202256
Filing Date: 2012-06-19
Classification: A61M

Abstract:
1. An injection device for injecting a dose of medication from a cartridge having a piston at one end and a membrane at an opposite end, the device comprising: a. a distal end from which medication can be expelled; b. an axially displaceable element that moves in a proximal direction during dose setting and that receives a force from user that is directed in a distal direction during injection; c. a piston drive element for engaging and moving the piston within the cartridge in a distal direction to expel medication from the cartridge; a gearing coupling the axially displaceable element with the piston drive element, the gearing increasing the force exerted by the user on the axially displaceable element so that a greater force is exerted on the piston drive element, the gearing comprising a first rack that is connected to the axially displaceable element, the first rack being in continuous meshed engagement with a pinion gear wheel during dose setting and injection of a dose, wherein the gearing causes the piston drive element to move a distance in a distal direction during injection that is less than the distance moved by the first rack, wherein the pinion gear wheel moves distally during injection of medication from the cartridge.