Automatic Injection Device with a Top Release Mechanism

• US 20080306446A1
• Filed: 01/20/2006
• Published: 12/11/2008
• Est. Priority Date: 01/21/2005
• Status: Active Grant

• Current Assignee: Novo Nordisk A/S
• Original Assignee: Novo Nordisk A/S
• Inventors: Markussen, Tom Hede
• Granted Patent: US 8,096,978 B2
• Time in Patent Office: Days
• US Class Current: 604/139
• CPC Class Codes: A61M 2005/202 cocking means, e.g. to bias the main drive spring of an injector
• 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 5/31525 Dosing burettes, pipettes B01L3/02
• CPC Class Codes: A61M 5/31528 by means of rotational movements, e.g. screw-thread mechanisms
• CPC Class Codes: A61M 5/31551 including axial movement of dose setting member
• CPC Class Codes: A61M 5/31553 without axial movement of dose setting member
• CPC Class Codes: A61M 5/3156 using volume steps only adjustable in discrete intervals, i.e. individually distinct intervals
• 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

Abstract

The present invention relates to a handheld mechanical injection device by which set doses of a liquid medicament can be injected from a medical reservoir. The medicament is expelled through an injection needle by release of a power reservoir in the device, the power reservoir being fully or partially released by actuation of a user operable release member being positioned at or near an upper end of the injection device, the upper end being that end of the injection device which is opposite the injection needle.

Claims

1. A handheld injection device (1) by which set doses of a liquid medicament can be injected from a medical reservoir through an injection needle (2) by release of a power reservoir (10) in the device, the power reservoir (10) being adapted to be fully or partially released by actuation of a user operable release member (3) positioned at or near an upper end of the injection device (1), the upper end being that end of the injection device (1) which is opposite the injection needle (2), the power reservoir (10) being adapted to be powered by rotation of a rotatably mounted dose setting member (7).

2. A handheld injection device according to claim 1, wherein the amount of power provided to the power reservoir (10) depends on the angle of rotation of the dose setting member (7).

3. A handheld injection device according to claim 1, wherein the release member is operatively connected to the dose setting member of the injection device.

4. A handheld injection device according to claim 3, wherein the release member engages the dose setting member via a key/keyway connection when the dose setting member is in a dose setting position.

5. A handheld injection device according to claim 4, wherein the release member is released from the key/keyway connection with the dose setting member when the dose setting member is in a dose injecting position.

6. A handheld injection device according to claim 1, wherein the release member is axially arranged relative to the injection device, and wherein the release member forms a push button like release member.

7. A handheld injection device according to claim 1, wherein the power reservoir comprises a resilient member, such as a torsion spring or a linear spring, the resilient member being, when released, adapted to press out a set dose of medicine from the medical reservoir through the injection needle.

8. A handheld injection device according to claim 1, further comprising a rotatably arranged drive member (8) being adapted to at least partly engage with at least part of a drive track of an associated piston rod (9), the drive member (8) being adapted to be positioned in a first axial position when the dose setting member (7) is in a dose setting position, the drive member (8) further being adapted to be positioned in a second axial position when the dose setting member (7) is in a dose injection position, the drive member (8) being adapted to release energy accumulated in the power reservoir (10) when the drive member (8) is in its second axial position.

9. A handheld injection device according to claim 8, wherein the drive member is adapted to rotate the associated piston rod upon releasing the accumulated energy in the power reservoir.

10. A handheld injection device according to claim 8, wherein the drive member is prevented from rotating when it is in its first axial position.

11. A handheld injection device according to claim 8, further comprising a resilient member, such as a linear spring, for biasing the drive member in a direction towards the dose setting member.

12. A handheld injection device according to claim 8, wherein the dose setting member is adapted to be moved a distance along an axial direction of the injection device so as to move the drive member between the first and second axial positions, the drive member being movable from the first to the second axial position by applying a force to the dose setting member, the force being applied along the axial direction of the injection device.

13. A handheld injection device according to claim 8, further comprising a rotatably mounted display member adapted to display the dose to be ejected from the injection device in accordance with a setting of the dose setting member, the rotatably mounted display member being rotatable over an angle corresponding to at least one revolution of the display member, the display member comprising a dose indicator barrel having numerals arranged along a substantially helical path on an outer surface thereof.

14. A handheld injection device according to claim 8, further comprising the associated the piston rod, the piston rod having a threaded outer surface with the drive track arranged in a longitudinal direction of the outer surface of the piston rod.

15. A handheld injection device according to claim 8, wherein the drive member is operatively connected to the dose setting member via a ratchet.