Injection device with cammed ram assembly

• US 8,496,619 B2
• Filed: 07/15/2011
• Issued: 07/30/2013
• Est. Priority Date: 07/15/2011
• Status: Active Grant

• Current Assignee: Antares Pharma Incorporated
• Original Assignee: Antares Pharma Incorporated
• Inventors: Kramer, Thomas, Rust, Matthew Howard, Goudreau, Paul Michael, Hoeft, Peter Anthony, Sund, Julius Craig, Sadowski, Peter L.
• Primary Examiner(s): BERDICHEVSKY, AARTI
• Application Number:
  US13/184,229
• Publication Number:
  US 20130018313A1
• Time in Patent Office: 746 Days
• Field of Search: 604/134, 604/135
• US Class Current: 604/135
• CPC Class Codes: A61M 2005/2013 triggering of discharging means by contact of injector with patient body
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/2073 preventing premature release, e.g. by making use of a safety lock
• CPC Class Codes: A61M 2005/3247 Means to impede repositioning of protection sleeve from needle covering to needle uncovering position
• CPC Class Codes: A61M 2205/584 having a color code
• 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
• CPC Class Codes: A61M 5/3007 with specially designed jet passages at the injector's distal end
• CPC Class Codes: A61M 5/3204 Needle cap remover, i.e. devices to dislodge protection cover from needle or needle hub, e.g. deshielding devices
• 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 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.

Claims

1. An injector, comprising:

a trigger mechanism including;

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, 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;

a user-operable firing-initiation member 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; and

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 trigger mechanism and configured to cause the axial rotation 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 housing.

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

3. The injector of claim 1, wherein the skin contacting member comprises a first cam, and the ram assembly comprises a second cam, the first cam being operatively associated with the second cam for camming the second cam upon the axial movement to rotate the ram assembly with respect to the retainer portion so as to position the ram assembly in the firing condition.

4. 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.

5. The injector of claim 4, wherein proximal movement of the user-operable firing-initiation member is blocked by the ram assembly when the injector is locked-out.

6. 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 window in the injector housing; and

an indicator having an indicator color that is absent from the pre-firing color gamut, which color is hidden from view within the injector 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.

7. The injector of claim 6, wherein the ram assembly includes the indicator.

8. The injector of claim 7, wherein the ram assembly entirely occludes the window in the fired condition.

9. The injector of claim 1, 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.

10. The injector of claim 9, wherein the needle is in fluid communication with the medicament container for injecting the medicament expelled therefrom during the firing.

11. The injector of claim 9, wherein the energy source and the needle are configured for jet injecting the medicament through the needle.

12. The injector of claim 11, 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.

13. The injector of claim 11, 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.

14. The injector of claim 1, wherein:

the trigger engagement member and the ram are in fixed association, such that rotation of the trigger engagement member rotates the ram; and

the ram assembly is associated with the firing-initiation member such that operation of the firing-initiation member rotates the ram assembly within the housing to the firing condition.

15. The injector of claim 14, 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.

16. The injector of claim 15, 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.

17. The injector of claim 15, 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.