Patent ID: 8617108

Claim:
A lifter assembly for actuating, a needle of an automatic medication delivery device the lifter assembly comprising: a motor having a motor shaft; a speed reduction device driven by the motor shaft and configured to reduce the rotational speed of the motor shaft; an output shaft driven by the weed reduction device via a rigid transmission device: a driving lever configured to move the needle the driving lever being connected to and driven by the output shaft; and a sensing device configured to sense the rotational position of the output shaft such that a position of the needle is precisely controlled, wherein the speed reduction device comprises a worm and a worm gear in mesh with the worm, the rigid transmission device comprising two parts pivotably connected with each other, one of the parts being pivotably connected to a portion of the worm gear offset from the center of the worm gear, the other of the parts being fixed to the output shaft and pivotable about an axis of the output shaft.