DRIVE MECHANISM OF A DRUG DELIVERY DEVICE

• US 20160045663A1
• Filed: 04/08/2014
• Published: 02/18/2016
• Est. Priority Date: 04/10/2013
• Status: Active Grant

• Current Assignee: Sanofi
• Original Assignee: Sanofi
• Inventors: Bayer, Stefan, Berning, Daniel, Blank, Philippe, Pelzer, Wolfgang, Wilden, Bjrn
• Granted Patent: US 10,478,562 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61M 2005/3126 Specific display means related to dosing
• CPC Class Codes: A61M 5/20 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 Class Codes: A61M 5/24 Ampoule syringes, i.e. syringes with needle for use in combination with replaceable ampoules or carpules, e.g. automatic ampoules or carpules A61J1/06
• CPC Class Codes: A61M 5/315 Pistons; Piston-rods; Guiding, blocking or restricting the movement of the rod or piston; Appliances on the rod for facilitating dosing ; Dosing mechanisms
• 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 5/31533 Dosing mechanisms, i.e. setting a dose administrating mechanisms A61M5/31565
• CPC Class Codes: A61M 5/31541 Means preventing setting of a dose beyond the amount remaining in the cartridge
• CPC Class Codes: A61M 5/31553 without axial movement of dose setting member
• 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 5/31593 Multi-dose, i.e. individually set dose repeatedly administered from the same medicament reservoir

Abstract

The present invention relates to a drive mechanism of a drug delivery device for setting and dispensing of a dose of a medicament, the mechanism comprising: —a housing (20), —a piston rod (120) to operably engage with a piston (14) of a cartridge (12) for displacing the piston (14) in a distal direction (1), —a dose indicating member (40) with a dose size information (48) thereon, connected to a spring element (100) and being rotatable in a dose incrementing direction (5) against the action of the spring element (100) for setting of a dose, —a drive wheel (130) operably engaged with the piston rod (120) for displacing the piston rod (120) in distal direction (1) for dose dispensing, —wherein the dose indicating member (40) is engageable with the drive wheel (130) during dose dispensing to transfer a driving force to the drive wheel (130) when driven by the relaxing spring element (100) in a dose decrementing direction (6).

Claims

1. A drive mechanism of a drug delivery device for setting and dispensing of a dose of a medicament, the mechanism comprising:

a housing (20),

a piston rod (120) to operably engage with a piston (14) of a cartridge (12) for displacing the piston (14) in a distal direction (1),

a dose indicating member (40) with a dose size information (48) thereon, connected to a spring element (100) and being rotatable in a dose incrementing direction (5) against the action of the spring element (100) for setting of a dose,

a drive wheel (130) operably engaged with the piston rod (120) for displacing the piston rod (120) in distal direction (1) for dose dispensing,

wherein the dose indicating member (40) is engageable with the drive wheel (130) during dose dispensing to transfer a driving force to the drive wheel (130) when driven by the relaxing spring element (100) in a dose decrementing direction (6).

2. The drive mechanism according to claim 1, wherein the dose indicating member (40) comprises a flat shaped dose indicating disc.

3. The drive mechanism according to any one of the preceding claims, wherein the spring element (100) comprises a spiral spring having a first end section (101) connected to the housing (20, 90) and having a second end section (102) connected to the dose indicating member (40).

4. The drive mechanism according to any one of the preceding claims, further comprising a ring-shaped dose setting member (30) rotatably supported by the housing (20) and being selectively engageable with the dose indicating member (40) for setting of a dose.

5. The drive mechanism according to any one of the preceding claims, further comprising a dose dispensing member (70) rotatably fixed to the housing (20) and being depressible in an axial direction (4) against the action of a dispensing spring element (84).

6. The drive mechanism according to claim 5, wherein the dose indicating member (40) axially abuts with the dose dispensing member (70).

8. The drive mechanism according to any one of the preceding claims 5 to 7, wherein the dose dispensing member (70) is radially enclosed by the dose setting member (30).

9. The drive mechanism according to any one of the preceding claims, wherein the dose indicating member (40) comprises a spiralled groove (42) to engage with a single dose limiting member (170).

10. The drive mechanism according to claim 9, wherein the single dose limiting member (170) is radially displaceable relative to the dose dispensing member (70) along the spiralled groove (42) and is rotatably fixed to the dose dispensing member (70).

11. The drive mechanism according to claim 10, wherein the dose dispensing member (70) comprises a radially outwardly extending appendix (76) engaged with a notch (171) of the single dose limiting member (70).

12. The drive mechanism according to any one the preceding claims 4 to 11, wherein the dose setting member (30) comprises a circumferential side wall portion (34) extending into the housing (20).

13. The drive mechanism according to claim 12, wherein a last dose limiting member (180) radially sandwiched between the side wall portion (34) and the housing (20) is threadedly engaged with the side wall portion (34) and rotatably locked to the housing (20).

14. The drive mechanism according to any one of the preceding claims, wherein the dose indicating member (40) comprises a centrally located toothed through opening (43) engaged with at least one resilient ratchet element (112) in a dose setting configuration.

15. A drug delivery device for setting and dispensing of a dose of a medicament, the device comprises:

a drive mechanism (3) according to any one of the preceding claims, and

a cartridge (12) containing the medicament and being arranged in the housing (20) of the drive mechanism (3).

7. The drive mechanism according to any one of the preceding 5 or 6, wherein the dose dispensing member (70) comprises a through opening (72) serving as a dose indicating window through which a portion of the dose size information (48) of the dose indicating member (40) is visibly displayed.