Needle assisted jet injection device having reduced trigger force

• US 9,364,611 B2
• Filed: 05/07/2013
• Issued: 06/14/2016
• Est. Priority Date: 05/07/2012
• Status: Active Grant

• Current Assignee: Antares Pharma Incorporated
• Original Assignee: Antares Pharma Incorporated
• Inventors: KraMer, Thomas, Rust, Matthew H., Goudreau, Paul M., Hoeft, Peter A., Sund, Julius C., Sadowski, Peter L., Travanty, Michael, Madsen, Patrick
• Primary Examiner(s): BERDICHEVSKY, AARTI
• Application Number:
  US13/889,190
• Publication Number:
  US 20130317431A1
• Time in Patent Office: 1,134 Days
• 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 2005/2026 Semi-automatic, e.g. user activated piston is assisted by additional source of energy
• 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 2005/3125 specific display means, e.g. to indicate dose setting
• CPC Class Codes: A61M 2202/0007 introduced into the body
• CPC Class Codes: A61M 2202/048 Anaesthetics
• 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 5/2053 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
• CPC Class Codes: A61M 5/326 Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user
• CPC Class Codes: A61M 5/5086 for indicating if defective, used, tampered with or unsterile

Abstract

An exemplary embodiment of an injector includes a trigger mechanism, an energy source, and a user-operable firing-initiation member. The trigger mechanism can include a floating trigger member having a retaining portion, a ram assembly having a ram configured to pressurize a medicament container for expelling a medicament therefrom, the ram assembly further having a floating trigger engagement member configured to engage the retaining portion of the floating trigger member when the floating trigger member is in a pre-firing condition. The energy source can be associated with the ram for powering the ram to expel the medicament, and the user-operable firing-initiation member can be operable for causing an axial rotation of the floating trigger member from the pre-firing condition to a firing condition in which the floating trigger engagement member is released from the retaining portion to allow the energy source to fire the ram.

Claims

1. An injector, comprising:

a trigger mechanism including;

a floating trigger member having a retaining portion, and

a ram assembly having a ram defining an axis and configured to pressurize a medicament container for expelling a medicament therefrom, the ram assembly further having a floating trigger engagement member configured to engage the retaining portion of the floating trigger member when the floating trigger member is in a pre-firing condition;

an energy source associated with the ram for powering the ram to expel the medicament; and

a user-operable firing-initiation member operable for causing a rotation of the floating trigger member about the axis from the pre-firing condition to a firing condition in which the floating trigger engagement member is released from the retaining portion to allow the energy source to fire the ram.

2. The injector of claim 1, further comprising an injector housing, wherein the firing initiation member includes a skin-contacting member disposed at a distal end of the injector that is movable proximally with respect to the housing when a force is applied to the skin-contacting member at the distal end of the injector, the firing initiation member being associated with the floating trigger member and configured to cause the axial rotation of the floating trigger member from the pre-firing condition to the firing condition upon a proximal movement of the skin-contacting member with respect to housing.

3. The injector of claim 1, wherein the ram assembly is of unitary construction.

4. The injector of claim 1, wherein the medicament comprises a midazolam.

5. The injector of claim 1, wherein the medicament comprises an androgen.

6. The injector of claim 5, wherein the androgen includes testosterone or a derivative or ester thereof.

7. The injector of claim 6, wherein the androgen includes testosterone cypionate.

8. The injector of claim 6, wherein the androgen includes testosterone enanthate.

9. The injector of claim 1, further comprising a container support that is configured for holding the medicament container during injection, and wherein the ram assembly is configured to engage the container support to lock-out the injector after an injection.

10. The injector of claim 9, wherein proximal movement of the user-operable firing-initiation member is blocked by the ram assembly when the injector is locked-out.

11. The injector of claim 1, wherein a pre-firing color gamut is visible from the exterior of the injector in the pre-firing condition, the injector further comprising:

a housing including a window; and

an indicator having an indicator color that is absent from the pre-firing color gamut, which color is hidden from view within the housing in the pre-fired condition,

wherein in the fired condition, the indicator color is visible through the window from an exterior of the injector for indicating the fired condition.

12. The injector of claim 11, wherein the ram assembly includes the indicator.

13. The injector of claim 12, wherein the ram assembly entirely occludes the window in the fired condition.

14. The injector of claim 1, further comprising an end cap, said end cap comprising a ram holding member that axially retains the ram assembly in a proximal position against action of the energy source in the pre-firing position, the retaining portion retaining the floating trigger engagement member engaged and held against firing by the ram holding member.

15. The injector of claim 14, wherein in the firing condition, the ram is disengaged from the retaining portion, and the energy source overcomes an engagement between the floating trigger engagement member and the ram holding member.

16. The injector of claim 14, wherein the ram holding member includes a projection that includes a bulge and a groove engaged with the floating trigger engagement member, and the retaining portion retains the engagement of the floating trigger engagement member with the bulge and groove in the pre-firing condition.

17. The injector of claim 2, wherein the skin-contacting member comprises a first cam, and the floating trigger member comprises a second cam, the first cam being operatively associated with the second cam so as to cause axial rotation of the floating trigger member from the pre-firing condition to the firing condition upon proximal movement of the skin-contacting member with respect to the housing.

18. The injector of claim 2, wherein the skin-contacting member includes a needle guard that is retractable and is configured to expose a needle connected to the medicament container upon the proximal movement of the skin-contacting member.

19. The injector of claim 18, wherein the needle is in fluid communication with the medicament container for injecting the medicament expelled therefrom during the firing.

20. The injector of claim 18, wherein the energy source and the needle are configured for jet injecting the medicament through the needle.

21. The injector of claim 20, wherein the energy source is configured to pressurize the medicament to between about 90 p.s.i. and about 500 p.s.i. to jet inject the medicament.

22. The injector of claim 20, wherein the energy source and needle are configured for injecting the medicament at an average velocity of at least about 1,000 cm/sec within the needle.