Engine and diffuser for use with a needle-less injector

• US 6,824,526 B2
• Filed: 10/22/2001
• Issued: 11/30/2004
• Est. Priority Date: 10/22/2001
• Status: Expired due to Fees

• Current Assignee: PenJet Corp.
• Original Assignee: PenJet Corp.
• Inventors: Castellano, Thomas P
• Primary Examiner(s): Casler, Brian L.
• Assistant Examiner(s): Thompson, Michael M
• Application Number:
  US10/086,374
• Publication Number:
  US 20030078535A1
• Time in Patent Office: 1,135 Days
• Field of Search: 604/68-73, 604/131, 604/140-147, 604/156, 604/236, 604/246, 604/74
• US Class Current: 604/68
• CPC Class Codes: A61M 2005/2073 preventing premature release, e.g. by making use of a safety lock
• 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 5/30 Syringes for injection by jet action, without needle, e.g. for use with replaceable ampoules or carpules

Abstract

A needle-less injector suitable for injecting fluid through a surface includes a housing, a driver, an engine and a trigger. The housing contains a fluid and the engine contains a compressed gas. Upon application of sufficient force to the trigger, the compressed gas is released from the engine forcing the driver through the interior of the housing, expelling the fluid from the housing at a speed sufficient to pierce an injection surface. An aerodynamic diffuser maximizes air flow to the driver, allowing greater injection speed and mitigating pain associated with receiving an injection. Use of the injector is both silent and easy to activate, owing to an O-ring included about the circumference of the exterior of a diffuser operating within the engine. Further, the engine has safety features preventing a portion thereof from separating from the device under elevated temperatures and similar conditions. Engine leakage is obviated by the inclusion of a leakage ring therein.

Claims

1. A needle-less injector suitable for injecting a fluid through a surface, said needle-less injector comprising:

a housing containing the fluid, said housing further containing at least one orifice;

an engine fitted within said housing, said engine containing a gas;

a diffuser affixed to said housing, said diffuser having an unobstructed air passage about its circumference and including at least one aerodynamic fin, said at least one aerodynamic fin being disposed in such a manner so as to aid in gas flow through said unobstructed air passage;

a driver that forces said fluid out of said housing, said driver being slidably disposed within said housing; and

a trigger coupled to said housing.

2. The needle-less injector in accordance with claim 1, said driver including:

a piston; and

a plunger.

3. The needle-less injector in accordance with claim 2, said plunger including:

a conical front end;

a conical back end; and

a cylindrical body.

4. The needle-less injector in accordance with claim 3, said plunger further comprising at least one ridge surrounding said cylindrical body.

5. The needle-less injector in accordance with claim 2, wherein

said plunger is symmetrical;

and

said plunger forms a substantially airtight seal with said housing.

6. The needle-less injector in accordance with claim 2, said piston including an expansion cup.

7. The needle-less injector in accordance with claim 1, further comprising a valve, said valve comprising:

a valve stem having a circular ridge;

a valve head affixed to said valve stem and said circular ridge;

a valve stem guide affixed to said engine; and

a spring having a first end resting against said circular ridge and a second end resting against said valve stem guide;

wherein depression of said trigger causes said valve to open.

8. The needle-less injector in accordance with claim 7, said valve including an airtight ring forming an airtight seal with said valve head upon closure of said valve.

9. The needle-less injector in accordance with claim 7, said diffuser including an O-ring to prevent leakage of said gas between said diffuser and said valve to a local atmosphere.

10. The needle-less injector in accordance with claim 1, said diffuser further including a locking ring and said engine further comprising at least one grip.

11. The needle-less injector in accordance with claim 10, wherein said at least one grip locks over said locking ring prior to use of said needle-less injector.

12. The needle-less injector in accordance with claim 1, wherein said diffuser includes three aerodynamic fins configured equidistant from one another about the circumference of said diffuser.

13. The needle-less injector in accordance with claim 1, further comprising an ampoule cap removably attached to said housing, wherein said ampoule cap forms an airtight seal over said orifice of said housing.

14. The needle-less injector in accordance with claim 1, said trigger including an end with a non-slip surface.

15. The needle-less injector in accordance with claim 1, said trigger further including at least one retainer hook mechanism and said housing further including at least one latch retainer mechanism.

16. The needle-less injector in accordance with claim 1, said diffuser further comprising a knife-edge of material about its circumference prior to said diffuser being affixed to said housing, said knife-edge of material being deformed when used as material to affix said diffuser to said housing.

17. The needle-less injector in accordance with claim 1, further including a safety clamp removably attached to said housing, wherein said safety claim prevents said trigger from moving relative to said housing in the axial direction of said at least one orifice.

18. The needle-less injector in accordance with claim 1, said housing further comprising at least one finger rest.

19. The needle-less injector in accordance with claim 1, said housing further including two finger rests disposed opposite one another, said finger rests having a non-slip surface.

20. The needle-less injector in accordance with claim 1, said needle-less injector remaining substantially silent upon administration of a needle-less injection.