Injection device with cammed ram assembly

Patent metadata

Field	Value
Publication number	US-11185642-B2
Application number	US-201916386443-A
Country	US
Kind code	B2
Filing date	Apr 17, 2019
Priority date	Jul 15, 2011
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

An exemplary embodiment of the present disclosure can provide an injector including a trigger mechanism, an energy source, and a user-operable firing-initiation member. The trigger member can include a trigger member having a retainer portion, and a ram assembly having a ram configured to pressurize a medicament container for expelling a medicament therefrom and a trigger engagement member configured to engage the retainer portion of the trigger member 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 between the trigger engagement member and the retainer portion from the pre-firing condition to a firing condition in which the trigger engagement member is released from the retainer portion to allow the energy source to fire the ram.

First claim

We claim:

1. An injector, comprising:
an injector housing;
a trigger mechanism including:
a trigger member having a retainer portion, and
a ram assembly having a ram for expelling a medicament from a medicament container and a ram surface, the ram assembly further having a trigger engagement member configured to engage the retainer portion of the trigger member in a pre-firing condition;

an energy source associated with the ram for powering the ram to expel the medicament; and
a needle guard moveable relative to the housing, the needle guard including a firing-initiation member having a needle guard surface configured to engage the ram surface so as to cause relative movement between the trigger engagement member and the retainer portion from the pre-firing condition to a firing condition.

2. The injector of claim 1 , 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 injector 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 trigger mechanism and configured to cause relative movement between the trigger engagement member and the retainer portion from the pre-firing condition to the firing condition upon a proximal movement of the skin-contacting member with respect to the injector housing.

3. The injector of claim 1 , further comprising a container support, and wherein the ram assembly is configured to engage the container support to lock-out the injector after an injection.

4. The injector of claim 1 , wherein the trigger engagement member is released from the retainer portion when the injector is in the firing condition such that the energy source fires the ram.

5. The injector of claim 1 , wherein the needle guard is retractable and is configured to expose a needle connected to the medicament container upon movement of the needle guard.

6. The injector of claim 5 , wherein the needle is in fluid communication with the medicament container for injecting the medicament expelled therefrom during the firing.

7. The injector of claim 5 , wherein the energy source and the needle are configured for jet injecting the medicament through the needle.

8. The injector of claim 1 , wherein the energy source pressurizes the medicament to between about 90 p.s.i. and about 500 p.s.i. to jet inject the medicament.

9. The injector of claim 1 , wherein the trigger mechanism comprises 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 retainer portion retaining the trigger engagement member engaged and held against firing by the ram holding member.

10. The injector of claim 9 , wherein in the firing condition, the ram is disengaged from the retainer portion, and the energy source overcomes an engagement between the trigger engagement member and the ram holding member.

11. The injector of claim 9 , wherein the ram holding member includes a projection that includes a bulge and a groove engaged with the trigger engagement member, and the retainer portion retains the engagement of the trigger engagement member with the bulge and groove in the pre-firing condition.

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

13. 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 dispensing the medicament.

14. The injector of claim 13 , wherein proximal movement of the firing-initiation member is blocked by the ram assembly when the injector is locked-out.

15. The injector of claim 1 , wherein a pre-firing color gamut is visible from an 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.

16. The injector of claim 15 , wherein the ram assembly includes the indicator.

17. The injector of claim 16 , wherein the ram assembly occludes the window in the fired condition.

18. The injector of claim 1 , wherein the ram surface is a first camming surface and the needle guard surface is a second camming surface, the first camming surface and second camming surface are operatively associated with one another.

19. The method of claim 18 , wherein the injection device includes a removable cap coupled to the needle guard to prevent displacement of the needle guard and wherein the method further comprises:
removing the removable cap prior to displacing the needle guard in a proximal direction.

20. The injector of claim 1 , wherein the ram surface is a first camming surface and the needle guard surface is a second camming surface, the first camming surface and second camming surface are operatively associated with one another.

21. The injector of claim 1 , wherein the medicament container is fixed relative to the injector housing.

22. A method of injecting a medicament comprising:
obtaining an injection device comprising:
a housing;
a trigger mechanism including a trigger member having a retainer portion, and a ram assembly having a ram for expelling a medicament from a medicament container and a ram surface, the ram assembly further having a trigger engagement member configured to engage the retainer portion of the trigger member in a pre-firing condition;
an energy source associated with the ram for powering the ram to expel the medicament; and
a needle guard including a firing-initiation member having a needle guard surface configured to engage the ram surface so as to cause relative movement between the trigger engagement member and the retainer portion from the pre-firing condition to a firing condition; and

displacing the needle guard relative to the housing in a proximal direction toward the ram such that the needle guard surface engages the ram surface and causing at least a portion of a needle to be exposed from a distal end of the needle guard, and causing the ram to be distally displaced by a force exerted on the ram by the energy source causing medicament to be dispensed from a distal end of the needle.

Assignees

• Antares Pharma Inc

Inventors

• Kramer Thomas E
• Rust Matthew H
• Goudreau Paul M
• Hoeft Peter A
• Sund Julius C
• Sadowski Peter L

Classifications

• A61M2005/2073

  preventing premature release, e.g. by making use of a safety lock · CPC title

• A61M5/3204

  Needle cap remover, i.e. devices to dislodge protection cover from needle or needle hub, e.g. deshielding devices · CPC title

• A61M2005/2013

  triggering of discharging means by contact of injector with patient body · CPC title

• A61M2005/206

  With automatic needle insertion · CPC title

• A61M2205/584

  having a color code · CPC title