Needle-free intradermal injection device

• US 9,433,735 B2
• Filed: 12/12/2012
• Issued: 09/06/2016
• Est. Priority Date: 12/13/2011
• Status: Active Grant

• Current Assignee: PharmaJet, Inc.
• Original Assignee: PharmaJet, Inc.
• Inventors: Cappello, Chris, Wixey, Matt, Bingham, John W.
• Primary Examiner(s): Stigell, Theodore
• Assistant Examiner(s): Legette, Tiffany
• Application Number:
  US13/711,765
• Publication Number:
  US 20130150820A1
• Time in Patent Office: 1,364 Days
• Field of Search: 604/68, 604/70, 604/110, 604/134, 604/135, 604/137, 604/138, 604/500, 604/187
• US Class Current: 1/1
• CPC Class Codes: A61M 2005/2013 triggering of discharging means by contact of injector with patient body
• CPC Class Codes: A61M 2005/202 cocking means, e.g. to bias the main drive spring of an injector
• CPC Class Codes: A61M 2005/2073 preventing premature release, e.g. by making use of a safety lock
• CPC Class Codes: A61M 2005/208 Release is possible only when device is pushed against the skin, e.g. using a trigger which is blocked or inactive when the device is not pushed against the skin
• 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 5/30 Syringes for injection by jet action, without needle, e.g. for use with replaceable ampoules or carpules

Abstract

A needle-free injection device suitable for delivering a therapeutic substance into the intradermal space of a patient. The needle-free injection device includes a main spring which can be compressed using one or more handles attached to the device to place the needle-free injection device into an armed configuration. Device embodiments may optionally include an injector tube and associated apparatus which may be moved relative to other device structures when the injector is pressed against the skin of a patient with sufficient force. The disclosed operational switches and release mechanisms cooperate to prevent injection unless the device is properly positioned for an injection. Needle-free injection systems and methods of operating a needle-free injection device are also disclosed.

Claims

1. A needle-free injection device comprising:

an injector body;

an injector tube positioned within the injector body, said injector tube housing a main spring configured to be selectively compressed to place the needle-free injection device in an armed configuration and a hammer, which injector tube is configured to move laterally away from a syringe end of the injector body when pressure is applied to a nozzle end of a needle-free syringe prior to an injection;

at least one handle attached with a pivot hinge to the injector body such that the handle pivots between an open and a closed position and such that the handle remains attached to the injector body during an injection;

a linkage between the handle and the main spring causing the main spring to be compressed into the armed configuration when the handle is moved from the open to the closed position; and

a retract button mechanically linked to the injector tube, the retract button causing the injector tube to be locked in a position toward the syringe end of the injector body, unless the retract button is activated.

2. The needle-free injection device of claim 1 further comprising a sleeve engaged with the linkage and the main spring which sleeve is configured to move laterally with respect to at least one handle compressing the main spring when the handle is moved from the open position to the closed position.

3. The needle-free injection device of claim 1 wherein the at least one handle comprises an upper handle and a lower handle and at least one upper linkage between the upper handle and the main spring and at least one lower linkage between the lower handle and the main spring.

4. The needle-free injection device of claim 3 further comprising a catch mechanism configured to engage the handles and hold each in the closed position.

5. The needle-free injection device of claim 4 further comprising a release mechanism configured to release the handles and allow each handle to move to the open position.

6. The needle-free injection device of claim 1 further comprising a skin tensioning spring configured to bias the injector tube toward the syringe end of the injector body.

7. The needle-free injection device of claim 1 further comprising an actuation button in mechanical communication with a hammer release, wherein the actuation button cannot engage the hammer release unless the injector tube is moved to a position fully away from the syringe end of the device.

8. The needle-free injection device of claim 7 wherein the hammer release comprises one or more ball bearings housed within a ball lock.

9. The needle-free injection device of claim 3 wherein at least one pivot hinge comprises;

two pivot studs with a first pivot stud being engaged with the upper handle and a second pivot stud being engaged with the lower handle; and

two radius surfaces with a first radius surface mating with a corresponding surface on the upper handle and a second radius surface mating with a corresponding surface on the lower handle.

10. A needle-free injection system comprising:

an injector body;

an injector tube positioned within the injector body, said injector tube housing a main spring configured to be selectively compressed to place the needle-free injection device in an armed configuration and a hammer, which injector tube is configured to move laterally away from a syringe end of the injector body when pressure is applied to a nozzle end of a needle-free syringe prior to an injection;

at least one handle pivotally attached with a pivot hinge to the injector body such that the handle pivots between an open and a closed position and such that the handle remains attached to the injector body during an injection;

a linkage between the handle and the main spring causing the main spring to be compressed into the armed configuration when the handle is moved from the open to the closed position;

a retract button mechanically linked to the injector tube, the retract button causing the injector tube to be locked in a position toward the syringe end of the injector body unless the retract button is activated; and

a needle-free syringe.

11. The needle-free injection system of claim 10 wherein the needle-free syringe comprises:

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 coplanar.

12. The needle-free injection system of claim 11 wherein the selected dosage volume is 0.1 ml.

13. The needle-free injection system of claim 11 wherein the needle-free syringe further comprises:

a handle substantially opposite the plunger body;

a separable shaft between the plunger body and handle; and

a break line defined in the separable shaft defining a zone where the handle is manually separable from the plunger body.

14. The needle-free injection system of claim 13 wherein the break line defines the hammer surface on the plunger body upon separation of the handle from the plunger body.

15. The needle-free injection system of claim 13 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 coplanar.

16. The needle-free injection system of claim 15 wherein the plunger positioning surface defines a hole.

17. A method of operating a needle-free injection device comprising:

providing a needle-free injection system comprising;

an injector body;

an injector tube positioned within the injector body, said injector tube housing a main spring and a hammer;

at least one handle attached with a pivot hinge to the injector body such that the handle pivots between an open and a closed position and such that the handle remains attached to the injector body during an injection;

a linkage between the handle and the main spring;

a retract button mechanically linked to the injector tube causing the injector tube to be locked in a position toward the syringe end of the injector body unless the retract button is activated; and

a needle-free syringe;

moving the handle from the open position to the closed position thereby compressing the main spring of the needle-free injection system from an un-armed position to an armed position;

activating the retract button to unlock the injector tube;

applying force against a patient'"'"'s skin at a nozzle end of the needle-free syringe thereby causing the injector tube to move laterally within the injector body away from a syringe end of the injector body.

18. The method of operating a needle-free injection device of claim 17 further comprising:

releasing energy stored in the main spring to drive a syringe plunger causing an injection.

19. The method of operating a needle-free injection device of claim 18 further comprising:

activating an actuation button when the injector tube has moved fully into an injection position with respect to the injector body, to release the energy stored in the main spring to drive the syringe plunger causing an injection.

20. The method of operating a needle-free injection device of claim 19 wherein the actuation button is not engaged with a hammer release until the injector tube is moved fully away from the syringe end of the injector body.