Apparatuses and method for injecting medicaments

An injector for delivering a medicament comprising:

• an outer sleeve;
• an inner sleeve disposed partially within the outer sleeve, the inner sleeve defining a chamber between a distal end and a proximal end of the inner sleeve and having an engagement member extending into the chamber at a position between the distal end and the proximal end;
• and
• a syringe having a barrel, a needle mounted to the distal end of the barrel, a plunger rod, and a seal slidably mounted in the barrel, wherein the plunger rod is engaged with the outer sleeve in a fixed spatial relationship such that the plunger rod and the outer sleeve translate as a unit throughout operation of the injector;
• wherein the outer sleeve is disposed and configured for axial translation relative to the inner sleeve, and wherein in a first configuration the engagement member is spaced apart from the barrel of the syringe and wherein in a second configuration the syringe contacts the engagement member such that continued axial translation of the outer sleeve causes translation of the plunger rod relative to the barrel to cause delivery of the medicament through the needle.

A method for operating an injector to deliver a medicament to a target location, the method comprising the steps:

• placing a distal end of an inner sleeve against the target location;
• applying a force to an outer sleeve, wherein applying the force to the outer sleeve causes axial translation of the outer sleeve and a syringe relative to the inner sleeve, causes a needle of the syringe to extend out from the distal end of the inner sleeve and into the target location, and causes the syringe to contact an engagement member of the inner sleeve;
• applying a continued force to the outer sleeve, wherein applying the continued force to the outer sleeve causes translation of a plunger rod and a seal within the syringe to cause delivery of the medicament;
• and
• removing the injector from the target location, wherein a biasing member applies a force on the inner sleeve to cause the inner sleeve to translate in the distal direction with respect to the outer sleeve to cover the needle of the syringe such that the inner sleeve is locked in place with respect to the outer sleeve.