Needle-free injection device

1. A needle-free injection device comprising:

an outer housing;

an inner housing, receiving a needle-free syringe in one end, the inner housing being moveable within the outer housing between a syringe loading position and a firing position;

an activation button operatively associated with the inner and outer housing; and

a housing lock engaged by the activation button to prohibit movement of the inner housing from the syringe loading position to the firing position when the activation button is activated in the syringe loading position;

a hammer within the inner housing communicating with a plunger within the needle-free syringe;

a release mechanism engaged by the activation button to release stored energy to power the hammer, wherein the activation button can only engage the release mechanism when the housing is in the firing position;

a lever associated with the activation button; and

a ball lock sleeve associated with the lever and the hammer such that articulation of the lever moves the ball lock sleeve releasing the hammer.

2. The needle-free injection device of claim 1 wherein the housing lock comprises an engagement surface on the activation button and a corresponding recess on the inner housing.

3. A needle-free injection device comprising:

an outer housing;

an inner housing, receiving a needle-free syringe in one end, the inner housing being movable within the outer housing between a syringe loading position and a firing position;

an activation button operatively associated with the inner and outer housing; and

a housing lock engaged by the activation button to prohibit movement of the inner housing from the syringe loading position to the firing position when the activation button is activated in the syringe loading position;

a hammer within the inner housing communication with a plunger within the needle-free syringe;

a release mechanism engaged by the activation button to release stored energy to power the hammer, wherein the activation button can only engage the release mechanism when the housing is in the firing position; and

a syringe mount to receive a needle-free syringe at one end of the inner housing, the syringe mount comprising an interlocking structure cooperating with the inner housing and outer housing to prevent the placement of a needle-free syringe into engagement with the syringe mount unless the inner housing is in the syringe loading position.

4. The needle-free injection system of claim 3 wherein the syringe mount comprises at least one rotating pawl providing for engagement with the needle-free syringe.

5. The needle-free injection system of claim 4 wherein the interlocking structure comprises:

a tab on the at least one pawl;

a corresponding opening through the inner housing; and

a corresponding space within the outer housing.

6. The needle-free injection system of claim 3 wherein the interlocking structure engages with the inner housing when a needle-free syringe is loaded such that force applied to a nozzle end of the needle-free syringe causes the inner housing to move from the syringe loading position toward the firing position.

7. The needle-free injection device of claim 3 wherein the interlocking structure further cooperates with the inner housing and outer housing to prevent the removal of a needle-free syringe from engagement with the syringe mount unless the inner housing is in the syringe loading position.

8. The needle-free injection device of claim 3 wherein the interlocking structure further cooperates with the inner housing and outer housing to prevent the inner housing from being moved from the syringe loading position to the firing position if a syringe is not properly loaded in the syringe mount.

9. The needle-free injection system of claim 3 further comprising an eject button associated with the syringe mount such that activation of the eject button causes the syringe mount to release a mounted needle-free syringe.

10. The needle-free injection system of claim 9 further comprising an extension on the outer housing that at least partially shields the eject button when the inner housing is moved from the syringe loading position toward the firing position.

11. The needle-free injection system of claim 9 further comprising a syringe eject spring providing sufficient force to completely eject a needle free syringe away from any contact with the needle-free injection system upon activation of the eject button.

12. The needle-free injection system of claim 3 further comprising:

at least two raised surfaces on the syringe body defining at least one orientation channel configured to mate with an orientation structure of the syringe mount; and

a grip edge defined by the raised surfaces which engages the syringe mount when a needle-free syringe is mounted, wherein the grip edge may be engaged with the syringe mount without rotating the syringe body or syringe mount.

13. A needle-free injection device comprising:

an outer housing;

an inner housing; and

a syringe mount to receive a needle-free syringe at one end of the inner housing, wherein the inner housing is moveable within the outer housing between a syringe loading position and a firing position; and wherein the syringe mount comprises an interlocking structure cooperating with the inner housing preventing the placement of a needle-free syringe into engagement with the syringe mount unless the inner housing is in the syringe loading position.

14. The needle-free injection system of claim 13 wherein the syringe mount comprises at least one rotating pawl providing for engagement with the needle-free syringe.

15. The needle-free injection system of claim 13 wherein the interlocking structure comprises:

a tab on the at least one pawl;

a corresponding opening through the inner housing; and

a corresponding space within the outer housing.

16. The needle-free injection system of claim 13 wherein the syringe mount interlock structure engages with the inner housing when a needle-free syringe is loaded such that force applied to a nozzle end of the needle-free syringe causes the inner housing to move from the syringe loading position toward the firing position.

17. The needle-free injection device of claim 16 wherein the interlocking structure further cooperates with the inner housing and outer housing to prevent the removal of a needle-free syringe from engagement with the syringe mount unless the inner housing is in the syringe loading position.

18. The needle-free injection device of claim 16 wherein the interlocking structure further cooperates with the inner housing and outer housing to prevent the inner housing from being moved from the syringe loading position to the firing position if a syringe is not properly loaded in the syringe mount.

19. The needle-free injection system of claim 13 further comprising an eject button associated with the syringe mount such that activation of the eject button causes the syringe mount to release a mounted needle-free syringe.

20. The needle-free injection system of claim 19 further comprising an extension on the outer housing that at least partially shields the eject button when the inner housing is moved from the syringe loading position toward the firing position.

21. The needle-free injection system of claim 19 further comprising a syringe eject spring providing sufficient force to completely eject a needle free syringe away from any contact with the system upon activation of the eject button.

22. The needle-free injection system of claim 13 further comprising:

at least two raised surfaces on the syringe body defining at least one orientation channel configured to mate with an orientation structure of the syringe mount; and

an edge defined by the raised surfaces which engages the syringe mount when a needle-free syringe is mounted, wherein the edge may be engaged with the syringe mount without rotating the syringe body or syringe mount.

23. A needle-free syringe system comprising:

a syringe body comprising a nozzle at one end and a dose setting surface substantially opposite the nozzle;

a plunger body comprising a leading end, a seal and a hammer surface substantially opposite the leading end, wherein the syringe body defines a dosage space within the syringe between the nozzle and the plunger seal, which dosage space has a selected dosage volume when the plunger body is positioned within the syringe body such that the dose setting surface and hammer surface are co-planar;

a handle substantially opposite the plunger body;

a separable shaft between the plunger body and handle;

a break line defined in the separable shafy, wherein the handle comprises a plunger positioning surface which cooperates with the hammer surface to position the plunger body in a needle-free syringe body such that the dose setting surface and hammer surface are co-planar.

24. The needle-free syringe system of claim 23 wherein the selected dosage volume is 0.5 ml.

25. The needle-free syringe system of claim 23 wherein the break line defines the hammer surface on the plunger body.

26. The needle-free syringe system of claim 23 wherein the plunger positioning surface defines a hole providing clearance for a nub formed in the hammer surface upon separation of the plunger body from the handle at the break line.

27. The needle-free syringe system of claim 23 further comprising:

a filling adapter;

a female conical surface defined by one of the syringe body and the filling adapter; and

a corresponding male conical surface defined by the other of the syringe body and the filling adapter such that the mated male and female conical surfaces form a fluid tight seal upon attachment of the filling adapter to the nozzle end of the syringe body.

28. A needle-free syringe system comprising:

a syringe body comprising a nozzle at one end and a dose setting surface substantially opposite the nozzle;

a plunger body comprising a leading end, a seal and a hammer surface substantially opposite the leading end, wherein the syringe body defines a dosage space within the syringe between the nozzle and the plunger seal, which dosage space has a selected dosage volume when the plunger body is positioned within the syringe body such that the dose setting surface and hammer surface are co-planar; and

a cap comprising:

an open ended cap body sized to engage the nozzle end of the syringe body; and

an annular flange at a closed end of the cap body providing a stand surface with a diameter greater than the diameter of the open end of the cap body.

29. A needle-free syringe system comprising:

a syringe body comprising a nozzle at one end;

a filling adapter;

a female conical surface defined by one of the syringe body and the filling adapter; and

a corresponding male conical surface defined by the other of the syringe body and the filling adapter such that the mated male and female conical surfaces form a fluid tight seal upon attachment of the filling adapter to the nozzle end of the syringe body.

30. The needle-free syringe system of claim 29 further comprising:

a male bayonet structure defined by one of the syringe body and the filling adapter; and

a corresponding female bayonet structure defined by the other of the syringe body and the filling adapter.

31. The needle-free syringe system of claim 29 further comprising:

a filling needle defining a fluid pathway through the filling adapter; and

one or more stability wings associated with the filling adapter and at least partially surrounding the filling needle.