Drive mechanism of a drug delivery device

Patent metadata

Field	Value
Publication number	US-10124118-B2
Application number	US-201414782723-A
Country	US
Kind code	B2
Filing date	Apr 8, 2014
Priority date	Apr 10, 2013
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

A drive mechanism of a drug delivery device for dispensing of a dose of a medicament includes a housing extending in an axial direction, a piston rod to operably engage with a piston of a cartridge to displace the piston in an axial distal direction, and a drive sleeve extending in the axial direction and being rotatable in a dose incrementing direction against the action of a spring enclosing at least an axial portion of the drive sleeve. The drive mechanism further includes a dose limiting member threadedly engaged with the drive sleeve, rotatably locked to the housing and at least partially extending radially between the drive sleeve and the spring, and at least one stop located on at least one of dose limiting member and drive sleeve for limiting an axial displacement of the dose limiting member relative to the drive sleeve.

First claim

The invention claimed is:

1. A drive mechanism of a drug delivery device for dispensing of a dose of a medicament, the drive mechanism comprising:
a housing extending in an axial direction;
a piston rod to operably engage with a piston of a cartridge to displace the piston in a distal direction;
a drive sleeve extending in the axial direction and being rotatable in a dose incrementing direction against a force of a spring enclosing at least an axial portion of the drive sleeve;
a dose limiting member threadedly engaged with the drive sleeve and rotatably locked to the housing, wherein at least a portion of the dose limiting member is located radially between the drive sleeve and the spring with respect to a longitudinal axis of the housing; and
at least one stop located on at least one of the dose limiting member and the drive sleeve for limiting an axial displacement of the dose limiting member relative to the drive sleeve.

2. The drive mechanism of claim 1 , wherein the dose limiting member and the housing comprise a radially outwardly extending protrusion configured to engage with a correspondingly shaped and axially extending groove.

3. The drive mechanism of claim 2 , wherein the protrusion is axially offset from an axial end of the spring.

4. The drive mechanism of claim 1 , wherein the dose limiting member comprises a shell-like profile extending only partially around a circumference of the drive sleeve, and oppositely located circumferential end sections of the dose limiting member each comprises a radially outwardly extending protrusion.

5. The drive mechanism of claim 4 , wherein the dose limiting member comprises a first radially inwardly extending stop configured to engage with a first radially outwardly extending stop of the drive sleeve when the dose limiting member reaches a dose limiting configuration.

6. The drive mechanism of claim 5 , wherein the first stop of the dose limiting member extends substantially midway between the radially outwardly extending protrusions of the oppositely located circumferential end sections of the dose limiting member.

7. The drive mechanism of claim 6 , wherein the dose limiting member comprises a second stop at a circumferential and axial edge thereof to engage with a radially outwardly extending second stop of the drive sleeve.

8. The drive mechanism of claim 7 , wherein the first radially inwardly extending stop and the second stop of the dose limiting member are located at opposite axial end sections of the dose limiting member.

9. The drive mechanism of claim 5 , wherein the first radially outwardly extending stop of the drive sleeve is located axially offset from an outer thread of the drive sleeve.

10. The drive mechanism of claim 1 , wherein the dose limiting member comprises a resilient, circumferentially extending clicking member to audibly engage with a correspondingly shaped recess or ledge of the drive sleeve before or when a stop of the dose limiting member engages with a corresponding stop of the drive sleeve.

11. The drive mechanism of claim 1 , wherein the drive sleeve is rotatably engaged with a dose indicating mechanism comprising a first spool and a second spool rotatably supported in the housing at a predefined distance in a substantially parallel orientation, wherein a dose indicating tape coiled onto the second spool is fixed with an end to an outer circumference of the first spool.

12. The drive mechanism of claim 11 , wherein the housing is adapted to receive an insert providing a bearing for at least one of first and second spools and/or providing at least one axially extending groove to engage with a protrusion of the dose limiting member.

13. The drive mechanism of claim 11 , wherein the second spool is rotatable against a force of a coil spring and wherein the first spool is permanently rotatably engaged with the drive sleeve.

14. The drive mechanism of claim 1 , wherein:
the drive sleeve is axially fixed relative to the housing,
the drive sleeve is hollow, and
at least one axially extending clutch member extending through the drive sleeve is rotatably locked to the drive sleeve and is axially displaceable relative to the drive sleeve to selectively engage with a drive wheel engaged with the piston rod for driving the piston rod in the distal direction.

15. The drive mechanism of claim 1 , further comprising a first stop located near a proximal end of the dose limiting member, and a second stop located near a distal end of the dose limiting member, the first and second stops configured to limit an axial displacement of the dose limiting member relative to the drive sleeve.

16. A drug delivery device for dispensing of a dose of a medicament, comprising:
a drive mechanism comprising
a housing extending in an axial direction,
a piston rod to operably engage with a piston of a cartridge to displace the piston in a distal direction,
a drive sleeve extending in the axial direction and being rotatable in a dose incrementing direction against a force of a spring enclosing at least an axial portion of the drive sleeve,
a dose limiting member threadedly engaged with the drive sleeve and rotatably locked to the housing, wherein at least a portion of the dose limiting member is located radially between the drive sleeve and the spring with respect to a longitudinal axis of the housing, and
at least one stop located on at least one of the dose limiting member and the drive sleeve for limiting an axial displacement of the dose limiting member relative to the drive sleeve; and

a cartridge at least partially filled with the medicament and being arranged in the housing of the drive mechanism or in a cartridge holder fixed to the housing.

17. The drug delivery device of claim 16 , wherein the dose limiting member and the housing comprise a radially outwardly extending protrusion configured to engage with a correspondingly shaped and axially extending groove.

18. The drug delivery device of claim 17 , wherein the protrusion is axially offset from an axial end of the spring.

19. The drug delivery device of claim 16 , wherein the dose limiting member comprises a shell-like profile extending only partially around a circumference of the drive sleeve, and oppositely located circumferential end sections of the dose limiting member each comprises a radially outwardly extending protrusion.

20. The drug delivery device of claim 19 , wherein the dose limiting member comprises a first radially inwardly extending stop configured to engage with a first radially outwardly extending stop of the drive sleeve when the dose limiting member reaches a dose limiting configuration.

21. The drug delivery device of claim 20 , wherein the first radially inwardly extending stop of the dose limiting member extends substantially midway between the radially outwardly extending protrusions of the oppositely located circumferential end sections of the dose limiting member.

22. The drug delivery device of claim 16 , further comprising a first stop located near a proximal end of the dose limiting member, and a second stop located near a distal end of the dose limiting member, the first and second stops configured to limit an axial displacement of the dose limiting member relative to the drive sleeve.

Assignees

• Sanofi Sa

Inventors

• Bayer Stefan
• Berning Daniel
• Blank Philippe
• Pelzer Wolfgang
• Wilden Björn

Classifications

• A61M5/31583

  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 title

• A61M5/31541 Primary

  Means preventing setting of a dose beyond the amount remaining in the cartridge · CPC title

• A61M2205/581

  by audible feedback · CPC title

• A61M5/3157

  Means providing feedback signals when administration is completed (A61M5/20 takes precedence) · CPC title

• A61M5/20

  Automatic syringes, e.g. with automatically actuated piston rod, with automatic needle injection, filling automatically (A61M5/142 {, A61M5/46} take precedence; {hypodermic projectiles F42B12/54}) · CPC title