DRIVE MECHANISM FOR A DRUG DELIVERY DEVICE AND DRUG DELIVERY DEVICE

• US 20130204204A1
• Filed: 06/09/2011
• Published: 08/08/2013
• Est. Priority Date: 06/11/2010
• Status: Active Grant

• Current Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Original Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Inventors: Horlock, Mark Philip, Butler, Stephen David
• Granted Patent: US 9,408,977 B2
• Time in Patent Office: Days
• US Class Current: 604/211
• CPC Class Codes: A61M 5/31528 by means of rotational movements, e.g. screw-thread mechanisms
• CPC Class Codes: A61M 5/31535 Means improving security or handling thereof, e.g. blocking means, means preventing insufficient dosing, means allowing correction of overset dose
• CPC Class Codes: A61M 5/31548 Mechanically operated dose setting member
• CPC Class Codes: A61M 5/3155 by rotational movement of dose setting member, e.g. during setting or filling of a syringe
• CPC Class Codes: A61M 5/31551 including axial movement of dose setting member
• CPC Class Codes: A61M 5/31555 by purely axial movement of dose setting member, e.g. during setting or filling of a syringe
• CPC Class Codes: A61M 5/31583 based on rotational translation, i.e. movement of piston rod is caused by relative rotation between the user activated actuator and the piston rod
• CPC Class Codes: A61M 5/31585 performed by axially moving actuator, e.g. an injection button
• CPC Class Codes: A61M 5/31593 Multi-dose, i.e. individually set dose repeatedly administered from the same medicament reservoir
• CPC Class Codes: F16H 25/12 with reciprocation along the axis of rotation, e.g. gearings with helical grooves and automatic reversal or cams
• CPC Class Codes: Y10T 74/18576 including screw and nut

Abstract

The drive mechanism comprises a drive member inside a housing, a rotation member and a dose member. The drive member is rotatable with respect to the housing. The rotation member is also rotatable and unidirectionally rotationally engaged with the drive member. The dose member is able to move along a set/deliver path between a first axial position and a second axial position in either direction or to move along a cancel path from the second axial position to the first axial position. An engagement of the dose member with the rotation member causes the rotation member to rotate when the dose member is moved along the set/deliver path. The drive member is not rotated when the dose member is moved along the cancel path. A button in/out spline can be provided for the set/deliver path and a cancel spline for the cancel path.

Claims

1-16. -16. (canceled)

17. A drive mechanism for a drug delivery device, comprising:

a housing,

a drive member arranged inside the housing, the drive member being rotatable with respect to the housing,

a rotation member rotatable with respect to the housing,

a dose member, which is movable between a first axial position with respect to the housing and a second axial position that is axially spaced from the first axial position,

an engagement of the dose member with the housing, the engagement allowing the dose member to move according to a set/deliver path between the first axial position and the second axial position in either direction or to move according to a cancel path from the second axial position to the first axial position, and

an engagement of the dose member with the rotation member and a unidirectional rotational engagement of the rotation member with the drive member by a clutch in such a manner that the rotation member is rotated when the dose member is moved according to the set/deliver path and the drive member is not rotated when the dose member is moved according to the cancel path.

18. The drive mechanism of claim 17, wherein the cancel path implies a helical movement of the dose member with respect to the housing.

19. The drive mechanism of claim 17, wherein the cancel path implies a helical movement of the dose member with respect to the housing and a subsequent rotation of the dose member within the first axial position.

20. The drive mechanism according to claim 17, wherein the set/deliver path is connected to the cancel path via a start path located between the second axial position and the cancel path and/or via an end path located between the cancel path and the first axial position.

21. The drive mechanism of claim 17, further comprising:

an engagement member being provided on the rotation member or on the dose member, the dose member being engaged with the rotation member by the engagement member being guided in a thread.

22. The drive mechanism of claim 17, further comprising:

a button in/out spline and a cancel spline,

the dose member being engaged with the housing by means of the button in/out spline and the cancel spline,

the button in/out spline being adapted to guide the movement of the dose member according to the set/deliver path, and

the cancel spline being adapted to guide the movement of the dose member according to the cancel path.

23. The drive mechanism of claim 22, further comprising:

at least one bump feature of the cancel spline, the bump feature impeding an entrance into the cancel path or an exit from the cancel path.

24. The drive mechanism of claim 17, further comprising:

the clutch being formed by an azimuthally arranged series of ramped teeth on the drive member and a corresponding azimuthally arranged further series of ramped teeth on the rotation member.

25. The drive mechanism of claim 17, further comprising:

a stop member rotationally locked with the housing,

the stop member being unidirectionally rotationally engaged with the drive member by a further clutch permitting a rotation of the drive member that is generated by a movement of the dose member from the second axial position to the first axial position according to the set/deliver path.

26. The drive mechanism of claim 25, further comprising:

the further clutch being formed by a further azimuthally arranged series of ramped teeth on the drive member and a corresponding azimuthally arranged further series of ramped teeth on the stop member.

27. The drive mechanism of claim 25, further comprising:

a resilient member which exerts a force tending to keep the drive member and the stop member in contact and to keep the drive member and the rotation member in contact.

28. The drive mechanism of claim 17, further comprising:

a piston rod arranged inside the housing, the piston rod being rotationally coupled with the drive member and being axially movable with respect to the drive member.

29. The drive mechanism of claim 28, wherein the movement of the dose member from the second axial position to the first axial position according to the set/deliver path generates an axial displacement of the piston rod with respect to the housing by a fixed predetermined distance.

30. The drive mechanism of claim 17, further comprising:

a unidirectional rotational engagement between the dose member or a button that is fixed to the dose member and the housing or an insert that is fixed to the housing.

31. The drive mechanism of claim 30, further comprising:

a ratchet insert comprising at least one pawl, the ratchet insert being rotationally locked with the dose member, and

a ratchet on the housing or insert, the pawl and the ratchet providing a unidirectional rotational engagement.

32. A drug delivery device in the shape of a pen-type injector comprising a drive mechanism according to claim 17.