Patent ID: 7090662

Claim:
A dose dial and drive mechanism for use in a drug delivery device comprising: a housing having a first end closest to a dispensing end of the device and a second end opposite the first end; a dose dial sleeve; a piston rod; a drive sleeve is threadedly connected to the said piston rod; a reset sleeve, which is located between said drive sleeve and said housing; and a dose display, characterized in that a) when said dose dial sleeve travels towards the second end of said housing the reset sleeve is carried with said dose dial sleeve towards the second end of said housing thereby resetting said dose display to a zero position; and b) when said dose dial sleeve and/or the reset sleeve travels towards the first end of said housing, the said dose dial sleeve and/or reset sleeve engage(s) with said drive sleeve thus advancing both said drive sleeve and said piston rod towards the first end of said housing.