Details for Patent: 9,610,409

Title:	Drive mechanisms suitable for use in drug delivery devices
Abstract:	A drive mechanism suitable for use in drug delivery devices is disclosed. The drive mechanism may be used with injector-type drug delivery devices, such as those permitting a user to set the delivery dose. The drive mechanism may include a housing, a dose dial sleeve, and a drive sleeve. A clutch is configured to permit rotation of the drive sleeve and the dose dial sleeve with respect to the housing when the dose dial sleeve and drive sleeve are coupled through the clutch. Conversely, when the dose dial sleeve and drive sleeve are in a de-coupled state, rotation of the dose dial sleeve with respect to the housing is permitted and rotation of the drive sleeve with respect to the housing is prevented. In the de-coupled state, axial movement of the drive sleeve transfers force in a longitudinal direction for actuation of a drug delivery device.
Inventor(s):	Veasey; Robert Frederick (Warwickshire, GB), Perkins; Robert (Warwickshire, GB), Plumptre; David Aubrey (Worcestershire, GB)
Assignee:	SANOFI-AVENTIS DEUTSCHLAND GMBH (Frankfurt am Main, DE)
Filing Date:	Jun 30, 2014
Application Number:	14/319,381
Claims:	1. A drive mechanism for use in a drug delivery device comprising: a housing comprising an inner surface having longitudinal splines; a dose dial sleeve threadedly engaged with the housing; a drive sleeve having an outer surface and releasably connected to the dose dial sleeve, where a proximal end of the drive sleeve comprises a distal and a proximal radially extending flange where threads are disposed on the outer surface between the flanges; and an end of life nut threadedly engaged with the threads on the outer surface of the drive sleeve between the two radially extending flanges, where the end of life nut has an outer surface configured to engage the splines on the inner surface of the housing to prevent rotation of the end of life nut relative to the housing and the drive sleeve, and where the end of life nut translates distally relative to the drive sleeve during dose setting and is axially fixed relative to the drive sleeve during dose delivery. 2. The drive mechanism of claim 1 further characterized in that the end of life nut engages the distal radially extending flange when the end of life nut has reached a final dose dispensed position. 3. The drive mechanism of claim 1 where the end of life nut has a threaded inner surface of a same pitch as the threads on the outer surface of the drive sleeve. 4. The drive mechanism of claim 1 where the end of life nut is a half nut configured to allow attachment to the outer surface of the drive sleeve between the two radially extending flanges during assembly of the drug delivery device. 5. The drive mechanism of claim 4 where the threads on the outer surface of the drive sleeve between the two radially extending flanges is a part thread. 6. The drive mechanism of claim 5 where the half nut is configured to advance distally along the part thread when the drive sleeve is rotated during dose setting. 7. The drive mechanism of claim 6 further characterized in that the advance of the half nut is proportional to a dialed dose. 8. The drive mechanism of claim 5 where the half nut is configured to advance proximally along the part thread when the drive sleeve is rotated to reduce an inadvertently set dose. 9. The drive mechanism of claim 1 where a distal face of the proximal radially extending flange has a radial stop configured to engage a radial stop on a proximal face of the end of life nut when the end of life nut is in a cartridge full position.