US Patent 9440026 Autoinjection devices

An autoinjection device includes a main body in the front end of which is slideably mounted a drawer or front body portion. The drawer can be opened to remove or insert a syringe. Closing the drawer while pressing a multifunction button primes the drive mechanism by latching it against trigger latch. Pressing the button gain while urging the front end causes the drawer to release the trigger latch. After the injection the drawer shrouds the used needle and can be released only by pressing the button.