Autoinjector

• US 20010005781A1
• Filed: 01/24/2001
• Published: 06/28/2001
• Est. Priority Date: 10/26/1998
• Status: Active Grant

• Current Assignee: Shl Medical AG
• Original Assignee: Mikael Amark, Thomas Bergens
• Inventors: Amark, Mikael, Bergens, Thomas
• Granted Patent: US 6,371,939 B2
• Time in Patent Office: Days
• US Class Current: 604/208
• 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 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, characterized in the improvement comprising

that 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.

2. The autoinjector of

claim 1

, characterized in that the penetration lock is arranged for holding the penetration head relative the housing and that the releasable injection lock is arranged for holding the injection head relative the housing, the carrier or the penetration head, in predetermined rear cocked positions.

3. The autoinjector of

claim 2

, characterized in that 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

, characterized in that the control system includes a manual trigger arrangement at least acting to release the penetration lock.

5. The autoinjector of

claim 1

, characterized in that the releasable injection lock is connected, directly or indirectly, between the injection head and the penetration head.

6. The autoinjector of

claim 1

, characterized in that 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

, characterized in that 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

, characterized in that a single drive acts as the penetration drive and the injection drive.

9. The autoinjector of

claim 8

, characterized in that the single drive acts on the injection head.

10. The autoinjector of

claim 9

, characterized in that 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

, characterized in that the penetration drive and the injection drive are separate, that the penetration drive is weaker than the injection drive and that the injection drive is arranged to apply force between the carrier and the injection head.

12. The autoinjector of

claim 11

, characterized in that an autoreturn mechanism is present and that 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

, characterized in that 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

, characterized in that the autoinjection mechanism comprises an autoreturn enabling mechanism based on force increase at piston bottoming out.

15. The autoinjector of

claim 14

, characterized in that the force is sensed between the injection head and the housing.

16. The autoinjector of

claim 14

, characterized in that the force is sensed between the injection head and the carrier or container.

17. The autoinjector of

claim 16

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

18. The autoinjector of

claim 14

to 17, characterized in that the injection drive includes a damper.

19. The autoinjector of

claim 1

, characterized in that an autoreturn mechanism is present and that 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

, characterized in that the damper is included in the penetration head.

21. The autoinjector of

claim 20

, characterized in that the damper includes a spring arranged in the axial direction and being weaker then the force of the penetration drive.

22. The autoinjector of

claim 21

, characterized in that the penetration head comprises at least two parts between which the spring is arranged.

23. The autoinjector of

claim 22

, characterized in that 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

, characterized in that the damper is included in the injection head.

25. The autoinjector of

claim 24

, characterized in that at least a part of the injection head is resilient and acts as damper.

26. The autoinjector of

claim 1

, characterized in that the damper is a viscous damper arranged to retard the autoinjection movement.

27. The autoinjector of

claim 26

, characterized in that the viscous damper retardation dominates over the syringe flow restrictions.

28. The autoinjector of

claim 26

, characterized in that the autopenetration movement is unretarded or at least less retarded than the autoinjection movement.

29. The autoinjector of

claim 26

, characterized in that 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

, characterized in that the viscous damper is arranged in parallel with the injection head movement.

31. The autoinjector of

claim 26

to 30, characterized in that the penetration drive is separate from, and provides a less strong force than, the injection drive.

32. The autoinjector of

claim 1

, characterized in that the carrier comprises a seat supporting the syringe barrel in a direction radial to the barrel axis and that a flexible or spring biased member is provided to force the barrel radially against the seat.

33. The autoinjector of

claim 32

, characterized in that the member is connected to a closure, allowing lateral insertion of the container in the carrier.

34. The autoinjector of

claim 32

, characterized in that the seat comprises an axially extending V-shaped trough.

35. The autoinjector of

claim 32

, characterized in that 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

, characterized in that the carrier is movable against a spring force biased in the rearward direction.