Patent ID: 7811260

Claim:
An apparatus for delivering a quantity of medication to bone marrow of a bone comprising: a driver assembly including a single motor; a plunger operating and cartridge drive mechanism rotatably engaged with the driver assembly, both driven by the single motor; a cartridge assembly having a drive connector attached thereto; the drive connector operable to be releasably engaged with the plunger operating and cartridge drive mechanism and operable to be rotated by the plunger operating and cartridge drive mechanism; a bone penetrating needle engaged with the cartridge assembly opposite from the drive connector whereby rotation of the cartridge assembly inserts the bone penetrating needle into the bone and bone marrow; a plunger operating assembly having a first, cocked position and a second, released position; a first spring operable to move the plunger operating assembly from its first position to its second position; a retractable sleeve operable to slide longitudinally relative to the plunger operating and cartridge drive mechanism; a second spring operable to bias the retractable sleeve to move from a retracted position to an extended position; a pawl latch assembly having a first position which releasably engages the plunger operating assembly in its first position; the pawl latch assembly having a second position which allows movement of the plunger operating assembly from its first position to its second position; a third spring operable to bias the pawl latch assembly in its first position; and a ramp formed on an inner surface of the retractable sleeve, the ramp operable to, in response to rotation of the plunger operating and cartridge drive mechanism and longitudinal movement of the retractable sleeve, move the pawl latch from its first position to its second position in order to release the plunger operating assembly from the first, cocked position to the second, released position.