DRUG DELIVERY DEVICE LAST DOSE LOCK-OUT MECHANISM

• US 20100324494A1
• Filed: 05/27/2010
• Published: 12/23/2010
• Est. Priority Date: 06/01/2009
• Status: Active Grant

• Current Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Original Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Inventors: Plumptre, David
• Granted Patent: US 9,199,040 B2
• Time in Patent Office: Days
• US Class Current: 604/207
• CPC Class Codes: A61M 5/31511 Piston or piston-rod constructions, e.g. connection of piston with piston-rod A61M5/5066 takes precedence
• CPC Class Codes: A61M 5/31541 Means preventing setting of a dose beyond the amount remaining in the cartridge
• CPC Class Codes: A61M 5/31551 including axial movement of dose setting member

Abstract

A method and system for limiting a maximum dose that may be set in a drug delivery device. A dose setting mechanism, which is operable to be coupled to a medication cartridge, comprises a lock-out mechanism that prevents one from setting a dose greater than the medication in the cartridge. The lock-out mechanism comprises a rotatable shaft. A helical groove having a first pitch is provided along a first portion of the rotatable shaft and a second pitch provided along a second portion of the rotatable shaft. The first pitch is different from the second pitch. A third pitch may be provided on a third portion of the shaft. This third pitch is provided at the end of the second pitch and is preferably different than the second pitch. The lock-out mechanism further comprises a non-rotating member disposed on the helical groove of said shaft. During dose setting, the shaft is rotated relative to the non-rotating member while the non-rotating member traverses along the groove from a proximal end of the shaft towards a distal end of the shaft.

Claims

1. A dose setting mechanism for a drug delivery device, wherein the dose setting mechanism is operable to be coupled to a cartridge housing of the drug delivery device that houses a cartridge of medication, the dose setting mechanism comprising:

a last dose lock-out mechanism preventing a user of said dose setting mechanism from setting a dose of said medication that is greater than said medication in said cartridge, said lock-out mechanism comprising;

a rotatable shaft;

a helical groove having a first pitch provided along a first portion of said rotatable shaft and a second pitch provided along a second portion of said rotatable shaft, said first pitch different from said second pitch; and

a non-rotating member disposed on said helical groove of said shaft,

wherein during dose setting of said drug delivery device, said shaft is rotated relative to said non-rotating member while said non-rotating member traverses along said groove from a first end of said shaft towards a second end of said shaft, and

wherein said non-rotating member traverses along said groove until a dose greater than said medication remaining in said cartridge is selected and said non-rotating member prevents said shaft from rotating and increasing said dose.

2. The invention of claim 1 wherein said rotating shaft comprises a start position and a stop position, wherein a distance between said start position and said stop position corresponds to an amount of medication contained in said cartridge.

3. The invention of claim 1 wherein said second pitch is greater than said first pitch.

4. The invention of claim 1 wherein when said dose is dispensed from said cartridge, said non-rotating member does not rotate relative to said shaft but rather both said non-rotating member and said shaft move in a substantially axial direction.

5. The invention of claim 1 wherein said non-rotating member comprises at least one spline feature, said at least one spline feature preventing relative rotation between said non-rotating member and a housing of said drug delivery device.

6. The invention of claim 1 wherein said non-rotating member comprises a partial thread.

7. The invention of claim 6 wherein said partial thread of said non-rotating member comprises two half turns of a two start thread.

8. The invention of claim 1 wherein said first portion is located near a distal end of said rotatable shaft and said second portion is located near a proximal end of said rotatable shaft.

9. The invention of claim 1 wherein said non-rotating member comprises at least one substantially radial stop face, said at least one substantially radial stop face engaging at least one stop face on said rotatable shaft so that said non-rotating member prevents said shaft from rotating.

10. The invention of claim 9 wherein said non-rotating member comprises a plurality of radial stop faces, said plurality of radial stop faces engaging a plurality of stop faces on said rotatable shaft so that said non-rotating member prevents said shaft from rotating.

11. The invention of claim 1 wherein said drug delivery device comprises a pen type drug delivery device.

12. The invention of claim 11 wherein said pen type drug delivery device comprises a non-reusable pen type drug delivery device.

13. The invention of claim 1 further comprising a third pitch provided along a third portion of said rotatable shaft.

14. The invention of claim 13 wherein said third pitch provided along said third portion of said rotatable shaft is similar to a thread of said non-rotating member.

15. The invention of claim 13 wherein said third pitch provided along said third portion of said rotatable shaft is different from said first pitch provided along said first portion of said rotatable shaft.

16. The invention of claim 13 wherein said third pitch provided along said third portion of said rotatable shaft is different from said second pitch provided along said second portion of said rotatable shaft.

17. The invention of claim 13 wherein said second pitch provided along said second portion of said rotatable shaft is greater than said third pitch provided along said third portion of said rotatable shaft.

18. The invention of claim 13 wherein said first pitch provided along said first portion of said rotatable shaft is generally equal to said third pitch provided along said third portion of said rotatable shaft.

19. The invention of claim 1 wherein said non-rotating member comprises a nut.

20. The invention of claim 19 wherein said nut is a complete circular nut.

21. The invention of claim 1, wherein the second portion begins at a location corresponding to the last 45 to 360 degrees of rotation when the shaft is rotated relative to said non-rotating member.

22. The invention of claim 1 wherein said first end of said shaft comprises a distal end and said second end of said shaft comprises a proximal end.

23. A method of limiting a dose that may be set in a drug delivery device, said method comprising the steps of:

loading a cartridge of medication in said drug delivery device;

providing a rotatable shaft;

defining a helical groove along a surface of said rotatable shaft, said helical groove having a first pitch along a first portion of said rotatable shaft and a second pitch along a second portion, said first pitch different from said second pitch;

disposing a non-rotating member on said helical groove of said shaft, and

rotating said shaft during dose setting of said drug delivery device, said shaft rotated relative to said non-rotating member while said non-rotating member traverses along said groove from a first end of said shaft towards a second end of said shaft,

selecting a dose equal to a permissible remaining dose in said drug delivery device; and

utilizing said non-rotating member to prevent a user from further rotating said shaft and increasing said dose.

24. The invention of claim 23 wherein said first end of said shaft comprises a distal end and said second end of said shaft comprises a proximal end.

25. The invention of claim 23 further comprising the step of

defining a start position along said rotating shaft, and

defining a stop position along said rotating shaft,

wherein a distance between said start position and said stop position corresponds to an amount of medication contained in said cartridge.

26. The invention of claim 23 further comprising the step of

providing said second pitch with a width that is greater than said first pitch.

27. The invention of claim 23 further comprising the step of

dispensing said dose from said cartridge,

preventing said non-rotating member from rotating relative to said shaft, and

moving both said non-rotating member and said shaft in a substantially axial direction.

28. The invention of claim 23 further comprising the step of

preventing relative rotation between said non-rotating member and a housing of said drug delivery device.

29. The invention of claim 23 further comprising the step of

locating said first portion near a distal end of said rotatable shaft and

locating said second portion near a proximal end of said rotatable shaft.

30. The invention of claim 23 further comprising the step of

engaging at least one substantially radial stop face with at least one stop face on said rotatable shaft so that said non-rotating member prevents said shaft from rotating.

31. The invention of claim 23 further comprising the step of

providing a third pitch along a third portion of said rotatable shaft.

32. The invention of claim 31 wherein said third pitch provided along said third portion of said rotatable shaft is similar to a thread of said non-rotating member.

33. The invention of claim 31 wherein said third pitch provided along said third portion of said rotatable shaft is different from said first pitch provided along said first portion of said rotatable shaft.

34. The invention of claim 31 wherein said third pitch provided along said third portion of said rotatable shaft is different from said second pitch provided along said second portion of said rotatable shaft.

35. The invention of claim 31 wherein said second pitch provided along said second portion of said rotatable shaft is greater than said third pitch provided along said third portion of said rotatable shaft.

36. The invention of claim 31 wherein said first pitch provided along said first portion of said rotatable shaft is generally equal to said third pitch provided along said third portion of said rotatable shaft.