A medication injection method where a dose set knob of a medication injection pen is rotated with respect to the housing of the medication injection pen during dose setting and dose correcting, a driver is selectively engages with the dose set knob, the driver being rotatably fixed with respect to the housing during dose setting and dose correcting, the driver is moved axially with the dose set knob during the dose setting and the dose correcting, and the driver is rotated with the dose set knob during an injection.

The present disclosure is generally directed to a drive mechanism for use in a drug delivery device having a cylindrical cartridge, i.e. a handheld injection device for selecting and dispensing a number of user variable doses of a medicament. The drive mechanism includes a base element, a toothed piston rod, which is guided within and movable relative to the base element, and a drive gear having a pinion, which is rotatably held in the base element and in meshed engagement with the toothed piston rod. The toothed piston rod includes multiple rigid rod pieces which are connected by hinges. The rigid rod pieces comprise a flat plate provided with a straight toothed rack.

The invention relates to an automatic injector device comprising a single-use, disposable, drug delivery assembly comprising a housing and a syringe assembly located at least partially within the housing, said syringe assembly including a plunger, a pre-filled unit-dose drug containing chamber, and needle, said plunger, drug containing chamber and needle being configured and dimensioned to function as an injection syringe; a reusable motorized transmission assembly comprising a housing, a motor and transmission assembly located within the housing, said transmission assembly being configured and dimensioned to engage the plunger of said syringe in the drug delivery assembly and expel said unit dose dmg from the drug containing chamber, into the needle and out of the drug delivery assembly; said single-use disposable drug delivery assembly and said reusable motorized transmission assembly are in substantial axial alignment along a longitudinal axis defined by the syringe, plunger, pre-filled unit-dose drug containing chamber, and needle.

A syringe having a mechanical ejection mechanism. The ejection mechanism includes an actuator and a rotational gear. The actuator has a retractable pawl configured to engage the gear when the actuator is displaced from a non-depressed position into a depressed position. Displacement of the actuator causes the gear to rotate by a predetermined angle. The rotation of the gear is translated into linear displacement of the plunger within the barrel, thereby ejecting a predetermined amount of solution from the barrel.

Syringe assemblies are described herein. A syringe assembly includes an assembly housing, a first syringe, a second syringe, and a connecting gear. The first syringe is disposed within the assembly housing. Each plunger is movable within the respective syringe cavity and defines a respective chamber in the respective syringe cavity, wherein the respective chamber is in fluid communication with the respective syringe port, the respective plunger comprising a respective gear rack extending longitudinally along the respective plunger. The connecting gear is rotatably coupled to the assembly housing. The connecting gear is configured to be in meshed engagement with at least one of the first gear rack and the second gear rack of the syringes.

An assembly for advancing a piston through a rotationally fixed cartridge includes a rotatable, axially fixed first member and an axially movable, rotatable second member connected thereto via a threaded connection and connectable to the piston. A friction pad is rotationally fixedly connected with the second member and includes first and second sets of fingers extending radially outwardly from a central disk. Both the first and second sets of fingers are configured to contact an interior side wall of the cartridge. The first set of fingers are angled toward a first rotational direction and are configured to wedge the friction pad between the side wall and the second member upon rotation of the first member in the first direction, thereby substantially preventing rotation in the first direction. The second set of fingers are angled toward a second rotational direction and are configured to substantially prevent rotation in the second direction.

The invention relates to an auto injector, by which a fixed dose of a medicament can be injected as self-treatment, and by which needle exposure to an accessible position, injection of the medicament and retraction of the needle to an inaccessible position is automatically performed as a continuous sequence, after the auto injector is triggered. The invention provides solutions to improve the functionality of the retraction of the needle and the general experience of the use.

An injection device includes a drive mechanism, and the drive mechanism in turn includes a drive rod being axially moveable, a plunger rod being axially moveable, and a gear assembly. The gear assembly is arranged such that an axial movement of the drive rod generates an axial movement of the plunger rod. This allows for a force transmission between the drive rod and the plunger rod, facilitating the expelling of viscous substances from the injection device.

Disclosed herein are delivery devices for delivering a volume of a drug product, placebo product, or other product including a fluid. The devices may include a barrel having a longitudinal axis, a proximal end region, and a distal end region. The proximal end region may include an opening, and the barrel may be configured to receive a drug therein. A plunger rod may be disposed at least partially inside the barrel and protruding from the opening. The plunger rod may include a rack having a plurality of teeth. The device may further include a pinion having a plurality of teeth configured to engage with the plurality of teeth of the rack, and rotation of the pinion against the rack may move at least a part of the plunger rod along the longitudinal axis of the barrel.

A medical delivery device for advancing a piston in a medicament container to expel a medicament. A support structure supports the container and a drive assembly that advances the piston. The drive assembly includes a drive ribbon that can be retracted and extended. The retracted ribbon defines a spiral and the extended ribbon defines a helix. The drive ribbon is incrementally moveable between the retracted spiral configuration and extended helical configuration. A mechanical drive rotates the drive ribbon to selectively extend and retract the ribbon. A thrust member having a helical ramp engages a proximal edge of the drive ribbon where it transitions between a spiral and helix. A bearing member at the distal end of the drive ribbon exerts an axial force on the piston when the ribbon is extended.