Pneumatic autoinjector with automated mixing

摘要

A pneumatic autoinjector that, once activated, automatically mixes at least two components in a pre-filled chamber and then ejects the mixture in a manner suitable for medicament injection. The mixable components may be a dry/wet combination (e.g., powder and solvent), wet/wet combination (e.g., two pre-diluted medicaments), wet/gas combination (e.g., chemical A and gas B), or gas/gas combination. In some embodiments, autoinjectors made in accordance with the teachings of the present disclosure may automatically perform a sequence comprising thorough medicament mixing (e.g., reconstitution of a dried medicament with solvent), an optional pause to enhance medicament dissolution or suspension, optional needle insertion into the patient (not required in needle-free embodiments), medicament injection into the patient, and optional needle retraction for safe storage.

主权项

1. An automatic injector for delivering a medicament, comprising:
an outer housing having proximal and distal ends; an inner housing disposed within the outer housing, the inner housing containing an activation channel and a medicament channel, the activation and medicament channels having proximal and distal ends and the inner housing having a cross-channel coupling located proximate the distal ends of the activation and medicament channels that fluidly couples the activation and medicament channels; an activation mechanism; and an activation impeding mechanism, the activation channel comprising:
a pressure-release mechanism associated with an activation spring;a flow control coupling located proximate the distal end of the activation channel and fluidly coupled with the medicament channel; anda pressurizable chamber containing a compressed gas, and the medicament channel comprising:
a pull rod retainer and a pressure-relief mechanism located at the distal end of the medicament channel;a medicament housing assembly including a medicament delivery mechanism and a medicament housing body slidably disposed within the medicament channel,the medicament housing body including proximal and distal ends and comprising:
a medicament chamber fluidly coupled with the medicament delivery mechanism and having proximal and distal ends;a valve disposed within the medicament chamber and separating two substances predisposed within the medicament chamber;a pull rod disposed within the medicament housing body and having proximal and distal ends, the distal end of the pull rod releasably coupled with the pull rod retainer and the proximal end of the pull rod coupled with the valve; anda plunger sealingly disposed about the pull rod within the medicament housing body.