Needle and hub assembly for automatic injector

• US 20040254543A1
• Filed: 03/11/2004
• Published: 12/16/2004
• Est. Priority Date: 10/10/2000
• Status: Active Grant

• Current Assignee: Meridian Medical Technologies Incorporated
• Original Assignee: Meridian Medical Technologies Incorporated
• Inventors: Griffiths, Steven M.
• Granted Patent: US 7,544,189 B2
• Time in Patent Office: Days
• US Class Current: 604/263
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/2462 by displacing occluding plugs
• CPC Class Codes: A61M 2005/3132 having flow passages for injection agents at the distal end of the barrel to bypass a sealing stopper after its displacement to this end due to internal pressure increase
• 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 5/2033 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 5/2066 comprising means for injection of two or more media, e.g. by mixing
• CPC Class Codes: A61M 5/2459 upon internal pressure increase, e.g. pierced or burst A61M5/2429 takes precedence
• CPC Class Codes: A61M 5/284 comprising means for injection of two or more media, e.g. by mixing
• CPC Class Codes: A61M 5/286 upon internal pressure increase, e.g. pierced or burst A61M5/283 takes precedence
• CPC Class Codes: A61M 5/3145 Filters incorporated in syringes
• CPC Class Codes: A61M 5/3293 characterised by features of the needle hub
• CPC Class Codes: A61M 5/34 Constructions for connecting the needle , e.g. to syringe nozzle or needle hub connecting catheter tubes to hubs A61M25/0014
• CPC Class Codes: A61M 5/343 Connection of needle cannula to needle hub, or directly to syringe nozzle without a needle hub A61M5/322 takes precedence
• CPC Class Codes: A61M 5/348 snap lock, i.e. upon axial displacement of needle assembly A61M5/344 takes precedence
• CPC Class Codes: Y10T 29/49826 Assembling or joining
• CPC Class Codes: Y10T 29/4984 Retaining clearance for motion between assembled parts
• CPC Class Codes: Y10T 29/49947 by applying separate fastener

Abstract

A needle and hub assembly for an automatic injector and a method for making the needle and hub assembly. The needle and hub assembly comprises a cap or skirt, a forward surface of which is interposed between and reinforced by first and second engaged hub portions. A needle is received in a contiguous channel formed in the two hub portions. The method for making the assembly comprises molding the first hub portion, placing the cap over the first hub portion, inserting the needle into a channel in the first hub portion, and then overmolding or otherwise forming the second hub portion on the exterior of the cap such that it is engaged with the first hub portion. An assembly created by this “two-shot” process can be used to seal a relatively large opening, and supports the needle more effectively than a conventional assembly.

Claims

1. A needle and hub assembly for an injection device, comprising:

a cap having an engaging portion adapted to engage an exterior surface of a cartridge, and a needle-supporting portion having a wall that includes an opening therein, the wall defining interior and exterior surfaces;

a first hub portion defining a needle-receiving channel through the opening in the wall and having a section that extends along the interior surface of the wall;

a needle mounted in the needle-receiving channel and extending outwardly therefrom; and

a second hub portion engaged with the first hub portion and receiving at least a portion of the needle, the second hub portion having reinforcing structures which extend outwardly along the exterior surface of the wall;

wherein the wall of the needle-supporting portion of the cap is reinforced on the interior surface by the first hub portion and on the exterior surface by the second hub portion.

2. The needle and hub assembly of claim 1, wherein the first and second hub portions are fused.

3. The needle and hub assembly of claim 2, wherein the first and second hub portions are comprised of a plastic.

4. The needle and hub assembly of claim 3, wherein the first and second hub portions are comprised of the same plastic.

5. The needle and hub assembly of claim 2, wherein the cap is comprised of a metal.

6. The needle and hub assembly of claim 5, wherein the cap is comprised of aluminum.

7. The needle and hub assembly of claim 2, wherein the reinforcing structures are radially-extending ribs.

8. The needle and hub assembly of claim 1, wherein the second hub portion further comprises a supporting portion that extends along the needle.

9. The needle and hub assembly of claim 1, wherein the needle-receiving channel provides a continuous flow pathway from the inside of the cap to the outside of the cap.

10. An automatic injector, comprising:

a housing;

a cartridge disposed in the housing, the cartridge having at least one opening therein and containing a medicament, the medicament being rearwardly confined by a plunger;

an actuation assembly including a stored energy source that is capable of being released to drive the plunger through the cartridge;

a cap having an engaging portion adapted to engage an exterior surface of the cartridge to cover the opening in the cartridge, and a needle-supporting portion having a wall that includes an opening therein, the wall defining interior and exterior surfaces;

a first hub portion defining a needle-receiving channel through the opening in the wall and having a section that extends along the interior surface of the wall;

a needle mounted in the needle-receiving channel and extending outwardly therefrom, the needle being adapted to expel the medicament when the plunger is driven through the cartridge; and

a second hub portion engaged with the first hub portion and receiving at least a portion of the needle, the second hub portion having reinforcing structures which extend outwardly along the exterior surface of the wall;

wherein the wall of the needle-supporting portion of the cap is reinforced on the interior surface by the first hub portion and on the exterior surface by the second hub portion.

11. The automatic injector of claim 10, wherein the first and second hub portions are fused.

12. The automatic injector of claim 11, wherein the first and second hub portions are comprised of a plastic.

13. The automatic injector of claim 12, wherein the first and second hub portions are comprised of the same plastic.

14. The automatic injector of claim 10, wherein the cap is comprised of a metal.

15. The automatic injector of claim 14, wherein the cap is comprised of aluminum.

16. The automatic injector of claim 10, wherein the reinforcing structures are radially-extending ribs.

17. The automatic injector of claim 10, wherein the second hub portion further comprises a supporting portion that extends along the needle.

18. The automatic injector of claim 10, wherein the needle-receiving channel provides a continuous flow pathway from the inside of the cap to the outside of the cap.

19. The automatic injector of claim 10, wherein the cartridge has two medicament compartments.

20. The automatic injector of claim 19, wherein one of the medicament compartments is adapted to house a wet medicament component and the other medicament compartment is adapted to house a dry medicament compartment.

21. The automatic injector of claim 20, wherein the at least one opening in the cartridge is in the dry medicament compartment.

22. A method of forming a needle and hub assembly, comprising:

forming a first hub portion;

providing a cap having an opening therein;

arranging the first hub portion such that the first hub portion has a portion thereof extending through the opening in the cap;

arranging a needle in a channel defined by the first hub portion; and

forming a second hub portion over an exterior surface of the cap such that the second hub portion engages the first hub portion and extends over at least a portion of the exterior surface of the cap.

23. The method of claim 22, wherein forming the first hub portion comprises injection molding the first hub portion.

24. The method of claim 22, wherein forming the second hub portion comprises injection molding the second hub portion.

25. The method of claim 22, further comprising, after inserting the needle in the channel and before forming the second hub portion, moving the assembly to a second mold having cavities defining the second hub portion.

26. The method of claim 22, wherein a portion of the first hub portion melts during the formation of the second hub portion such that a melt zone forms securing the first hub portion to the second hub portion.

27. A method of assembling an automatic injector, comprising:

filling a dry medicament compartment with a dry medicament component using an opening in the dry medicament compartment; and

sealing the opening in the dry medicament compartment by placing the needle and hub assembly of claim 22 over the opening.