Autoinjector

• US 6,270,479 B1
• Filed: 10/04/1999
• Issued: 08/07/2001
• Est. Priority Date: 10/26/1998
• Status: Expired due to Term

• Current Assignee: Shl Medical AG
• Original Assignee: Pharmacia AB (Pharmacia Corp.)
• Inventors: Åmark, Mikael, Bergens, Thomas
• Primary Examiner(s): MENDEZ, MANUEL A
• Application Number:
  US09/411,954
• Time in Patent Office: 673 Days
• Field of Search: 604/95.01, 604/95.02, 604/110, 604/130, 604/131, 604/132, 604/133, 604/134, 604/135, 604/136, 604/138, 604/139, 604/156-158, 604/192-196, 604/198-199, 604/218, 604/232, 606/172, 606/182, 128/DIG.1, 128/DIG.12, 128/DIG.13
• US Class Current: 604/156
• CPC Class Codes: A61M 2005/202 cocking means, e.g. to bias the main drive spring of an injector
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/2086 having piston damping means, e.g. axially or rotationally acting retarders
• CPC Class Codes: A61M 2005/2418 comprising means for damping shocks on ampoule
• CPC Class Codes: A61M 2005/3143 Damping means for syringe components executing relative movements, e.g. retarders or attenuators slowing down or timing syringe mechanisms
• CPC Class Codes: A61M 5/2033 Spring-loaded one-shot injectors with or without automatic needle insertion multishot dosing syringes A61M5/31525, needle insertion only A61M5/3287
• CPC Class Codes: A61M 5/2053 Media being expelled from injector by pressurised fluid or vacuum for infusion A61M5/145, A61M5/155
• 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 5/3204 Needle cap remover, i.e. devices to dislodge protection cover from needle or needle hub, e.g. deshielding devices
• CPC Class Codes: A61M 5/326 Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user

Abstract

An autoinjector for replaceable containers of syringe type, comprising a barrel of axially roughly constant cross-section, a front opening with or for an injection needle and at least one movable rear piston, optionally with a plunger connected thereto, inserted in the barrel for the displacement of a container content, the autoinjector comprising a) a housing, b) a container carrier, arranged for reception of the container and arranged movably in relation to the housing in container axial direction between a rear, needle-covering, position and a forward, needle-exposing, position, c) an autopenetration mechanism, comprising at least a penetration head and a penetration drive, the penetration head being arranged for movement of the barrel or carrier in the forward direction and the penetration drive being operable to apply force between the housing and the penetration head, d) an autoinjection mechanism, comprising at least an injection head and an injection drive, the injection head being arranged for movement of the piston or plunger in the forward direction and the injection drive being operable to apply force between the housing or the carrier and the injection head, e) optionally an autoreturn mechanism operable to apply force between the housing and the barrel or carrier for movement thereof in the rearward direction and f) a control system for sequencing the operation of at least the autopenetration and autoinjection mechanisms, at least comprising a releasable penetration lock for the autopenetration mechanism and a releasable injection lock for the autoinjection mechanism. The carrier is designed to accommodate either of at least two containers of different length and/or width and at least one damper arranged for energy absorption from the autopenetration and/or autoinjection movement.

Claims

1. An autoinjector for replaceable containers of syringe type, comprising a barrel of axially roughly constant cross-section, a front opening with or for an injection needle and at least one movable rear piston, optionally with a plunger connected thereto, inserted in the barrel for the displacement of a container content, the autoinjector comprising a) a housing, b) a container carrier, arranged for reception of the container and arranged movably in relation to the housing in container axial direction between a rear, needle-covering, position and a forward, needle-exposing, position, c) an autopenetration mechanism, comprising at least a penetration head and penetration drive, the penetration head being arranged for movement of the barrel or carrier in the forward direction and the penetration drive being operable to apply force between the housing and the penetration head, d) an autoinjection mechanism, comprising at least an injection head and an injection drive, the injection head being arranged for movement of the piston or plunger in the forward direction and the injection drive being operable to apply force between the housing or the carrier and the injection head, e) optionally an autoreturn mechanism operable to apply force between the housing and the barrel or carrier for movement thereof in the rearward direction, and f) a control system for sequencing the operation of at least the autopenetration and autoinjection mechanisms, comprising a releasable penetration lock for the autopenetration mechanism and a releasable injection lock for the autoinjection mechanism, wherein the carrier is designed to accommodate either of at least two containers of different length and/or width, and the autoinjector further comprises at least one damper arranged for energy absorption from the autopenetration and/or autoinjection movement.

2. The autoinjector of claim 1, wherein the penetration lock is arranged for holding the penetration head relative to the housing and the releasable injection lock is arranged for holding the injection head relative to the housing, the carrier or the penetration head, in predetermined rear cocked positions.

3. The autoinjector of claim 2, wherein, in the cocked positions, there is a space between the penetration head and the barrel or carrier and a space between the injection head and the piston or plunger, respectively.

4. The autoinjector of claim 1, within the control system includes a manual trigger arrangement at least acting to release the penetration lock.

5. The autoinjector of claim 1, within the releasable injection lock is connected, directly or indirectly, between the injection head and the penetration head.

6. The autoinjector of claim 1, wherein the control system includes a structure on the housing releasing the injection lock at a predetermined axial injection enabling position.

7. The autoinjector of claim 6, wherein, in the injection enabling position, there is a space between the injection head and the piston or plunger, respectively.

8. The autoinjector of claim 1, wherein a single drive acts as the penetration drive and the injection drive.

9. The autoinjector of claim 8, wherein the single drive acts on the injection head.

10. The autoinjector of claim 9, wherein an autoreturn mechanism is present and that the control system comprises an autoreturn enabling mechanism disengaging the container and carrier from the single drive.

11. The autoinjector of claim 1, wherein the penetration drive and the injection drive are separate, the penetration drive is weaker than the injection drive, and the injection drive is arranged to apply force between the carrier and the injection head.

12. The autoinjector of claim 11, wherein an autoreturn mechanism is present and the control system comprises an autoreturn enabling mechanism disengaging the container and carrier from the penetration drive.

13. The autoinjector of claim 10 or 12, wherein the autoreturn enabling mechanism includes a release structure, arranged to enable the disengagement, with predetermined axial location in relation to the container front.

14. The autoinjector of claim 10 or 12, wherein the autoinjection mechanism comprises an autoreturn enabling mechanism based on force increase at piston bottoming out.

15. The autoinjector of claim 14, wherein the force is sensed between the injection head and the housing.

16. The autoinjector of claim 14, wherein the force is sensed between the injection head and the carrier or container.

17. The autoinjector of claim 16, wherein the autoinjection mechanism comprises an injection conveyor, the injection drive acts between the injection head and the injection conveyor, the injection conveyor is connected to the carrier in an axially movable manner with respect to the carrier, a counterforce weaker than the force of the injection drive is arranged between the injection carrier and the conveyor, and the autoreturn enabling mechanism includes a release mechanism acting on a relative movement between the injection conveyor and the carrier.

18. The autoinjector of claim 14, wherein the injection drive includes a damper.

19. The autoinjector of claim 1, wherein an autoreturn mechanism is present and the control system comprises an autoreturn enabling mechanism disengaging the container and carrier from the autopenetration force and the autoinjection force.

20. The autoinjector of claim 1, wherein the damper is included in the penetration head.

21. The autoinjector of claim 20, wherein the damper includes a spring arranged in the axial direction, and further wherein the spring force is weaker than the force of the penetration drive.

22. The autoinjector of claim 21, wherein the penetration head comprises at least two parts between which the spring is arranged.

23. The autoinjector of claim 22, wherein the control system is arranged to enable the autoinjection mechanism at relative movement between the two parts of the penetration head.

24. The autoinjector of claim 1, wherein the damper is included in the injection head.

25. The autoinjector of claim 24, wherein at least a part of the injection head is resilient and is operable as a damper.

26. The autoinjector of claim 1, wherein the damper is a viscous damper arranged to retard the autoinjection movement.

27. The autoinjector of claim 26, wherein the viscous damper retardation dominates over the syringe flow restrictions.

28. The autoinjector of claim 26, wherein the autopenetration movement is unretarded or is at least less retarded than the autoinjection movement.

29. The autoinjector of claim 26, wherein the viscous damper is connected, directly or indirectly, between the penetration head and the injection head, to act at relative motions therebetween.

30. The autoinjector of claim 26, wherein the viscous damper is arranged in parallel with the injection head movement.

31. The autoinjector of claim 26 to 30, wherein the penetration drive is separate from, and provides a less strong force than, the injection drive.

32. The autoinjector of claim 1, wherein the carrier comprises a seat supporting the syringe barrel in a direction radial to the barrel axis and a flexible or spring biased member is provided to force the barrel radially against the seat.

33. The autoinjector of claim 32, wherein the member is connected to a closure, allowing lateral insertion of the container in the carrier.

34. The autoinjector of claim 32, wherein the seat comprises an axially extending V-shaped trough.

35. The autoinjector of claim 32, wherein the seat comprises a front constriction, narrower than the container barrel and wider than the container needle, arranged to prevent the container front passing the constriction in the forward direction.

36. The autoinjector of claim 1, wherein the carrier is movable against a spring force biased in the rearward direction.

37. The autoinjector of claim 12, wherein the autoreturn enabling mechanism includes a release structure, arranged to enable the disengagement, with predetermined axial location in relation to the container front.

38. The autoinjector of claim 12, wherein the autoinjection mechanism comprises an autoreturn enabling mechanism based on force increase at piston bottoming out.

39. The autoinjector of claim 38, wherein the force is sensed between the injection head and the carrier or the container.

40. The autoinjector of claim 39, wherein the autoinjection mechanism comprises an injection conveyor, the injection drive acts between the injection head and the injection conveyor, the injection conveyor is connected to the carrier in an axially movable manner with respect to the carrier, a counterforce weaker than the force of the injection drive is arranged between the injection carrier and the conveyor, and the autoreturn enabling mechanism includes a release mechanism acting on a relative movement between the injection conveyor and the carrier.

41. The autoinjector of claim 38, wherein the injection drive includes a damper.