Drug delivery device provided with a one-way mechanism

• US 20020004651A1
• Filed: 03/30/2001
• Published: 01/10/2002
• Est. Priority Date: 04/13/2000
• Status: Active Grant

• Current Assignee: Novo Nordisk A/S
• Original Assignee: Novo Nordisk A/S
• Inventors: Aasmul, Soren, Poulsen, Jens Ulrik, Moller-Jensen, Peter, Moller-Jensen, Jens, Christensen, Lars Hofmann, Ljunggreen, Henrik
• Granted Patent: US 6,585,699 B2
• Time in Patent Office: Days
• US Class Current: 604/218
• CPC Class Codes: A61M 2005/31518 designed to reduce the overall size of an injection device, e.g. using flexible or pivotally connected chain-like rod members
• CPC Class Codes: A61M 2005/31588 electrically driven
• CPC Class Codes: A61M 5/31501 Means for blocking or restricting the movement of the rod or piston A61M5/5013 takes precedence
• 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 5/31543 piston rod reset means, i.e. means for causing or facilitating retraction of piston rod to its starting position during cartridge change
• CPC Class Codes: A61M 5/3156 using volume steps only adjustable in discrete intervals, i.e. individually distinct intervals
• 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

A drug delivery device comprising a housing (1) with a drug container (2) being provided with delivering means comprising a piston (5) for expelling a drug (4) from the drug container (2). The housing (1) further comprising a displaceable piston rod (6) abutting the piston (5) of the drug container (2) and rotating means being in engagement with the piston rod (6), said rotating means being provided with a one-way mechanism. The one-way mechanism comprises a helical spring (12) wound tightly around an axle (11), one end of said helical spring (12) being fixed in relation to the housing (1), the other end of the helical spring (12) being in a free state.

Claims

1. A drug delivery device comprising a housing (1) with a drug container (2), said drug container (2) having delivering means comprising a piston (5) for expelling a drug (4) from the drug container (2), said housing (1) further comprising a displaceable piston rod (6) abutting the piston (5) of the drug container (2), rotating means being in engagement with the piston rod (6), said rotating means being provided with a one-way mechanism, characterised in that the one-way mechanism comprises a helical spring (12) wound tightly around an axle (11), one end of said helical spring (12) being fixed in relation to the housing (1), the other end of the helical spring (12) being in a free state.

2. A drug delivery device according to claim 1 characterised in that a release button (15) is provided, said release button (15) being able to displace the free end of the helical spring (12) in a direction of unwinding the helical spring (12).

3. A drug delivery device according to claims 1 or 2, characterised in that the piston rod (6) is provided with a toothing (7) and is in engagement with a piston rod driving wheel (8) provided with a complementary toothing (9), said piston rod driving wheel (8) being mounted on said axle (11).

4. A drug delivery device according to claim 3, characterised in that the piston rod (6) is flexible and is positioned partly around the piston rod driving wheel (8).

5. A drug delivery device according to claim 4, characterised in that a guiding face (10) is provided in the housing (1), said flexible piston rod (6) being positioned between said guiding face (10) and said piston rod driving wheel (8).

6. A drug delivery device according to any one of claims 1-5, characterised in that the drug delivery device is provided with an exchangeable drug container (2).

7. A drug delivery device according to any one of claims 1-6, characterised in that the drug delivery device is an injection syringe.