A drive mechanism suitable for use in drug delivery devices is disclosed. The drive mechanism may be used with injector-type drug delivery devices, such as those permitting a user to set the delivery dose. The drive mechanism may include a housing, a dose dial sleeve, and a drive sleeve. A clutch is configured to permit rotation of the drive sleeve and the dose dial sleeve with respect to the housing when the dose dial sleeve and drive sleeve are coupled through the clutch. Conversely, when the dose dial sleeve and drive sleeve are in a de-coupled state, rotation of the dose dial sleeve with respect to the housing is permitted and rotation of the drive sleeve with respect to the housing is prevented. In the de-coupled state, axial movement of the drive sleeve transfers force in a longitudinal direction for actuation of a drug delivery device.

The invention relates to a torsion spring driven injection device for delivering set doses of a liquid drug wherein a torsion spring is strained by rotation of a rotatable dose setting structure and released by proximal movement of a piston rod driver. The dose setting structure is coupled to a drive element which is rotated during dose setting and which drive element is released during dosing to thereby rotate the piston rod driver. The piston rod driver is further coupled to the piston rod to generate a rotation and thus forward movement of the piston rod. The drive element and the piston rod driver are coupled to each other by a toothed engagement which is functional both during dose setting and during dose expelling.

Drug delivery devices and related methods of assembly are disclosed. The drug delivery device may include a main housing having an interior surface defining an enclosed space, and an exterior surface releasably attachable to a patient. A container may be disposed in the enclosed space and include a reservoir containing a drug and a stopper. A drive assembly may also be disposed in the enclosed space and configured to move the stopper through the reservoir to expel the drug from the reservoir. The drive assembly may include a rotational power source and a gear module. The gear module may include a mounting plate and a plurality of gears rotatably connected to the mounting plate. Furthermore, the mounting plate may be separate from the main housing.

Drug delivery devices are configured to include a gas-driven piston assembly having a flexible pushrod, a non-linear guide include a non-linear guide pathway at least partially surrounding the flexible pushrod, a cylinder at least partially surrounding the flexible pushrod, and a piston movable within the cylinder in response to the pressurized gas entering the cylinder. Some arrangements include a roller pushrod guide system and/or a gear pushrod guide system.

This pharmaceutical injection device may be provided with a main body case, a pharmaceutical syringe mounting portion, a piston, a piston feed screw or the like, and a cover. At a first end, the main body case may have an injection needle mounting portion to which an injection needle is mounted. The pharmaceutical syringe mounting portion may be provided inside the main body case, and a pharmaceutical syringe may be mounted thereto. The piston may be provided movably with respect to the pharmaceutical syringe that is mounted to the pharmaceutical syringe mounting portion. The piston feed screw or the like drives the piston. The cover may be provided on the first end side of the main body case and operates to open and close the injection needle mounting portion.

An injection device having a drive member with first and second gear patterns that are fixed relative to each other. The drive member is rotatable and translatable in first and second opposing axial directions. A plunger expels medicament from a cartridge when it is translated in an advancing direction. A dosage indicator indicates a set dosage. A first gearing arrangement operably couples the first gear pattern with the plunger wherein rotation of the drive member in a first direction translates the drive member in a first axial direction without movement of the plunger and translation of the drive member in the opposite axial direction drives the plunger in the advancing direction. A second gearing arrangement operably couples the second gear pattern with the dosage indicator and moves the dosage indicator to indicate an increase in the set dosage when the drive member is translated in the first axial direction.

An autoinjector device includes a dose cassette having an outer container and a needle cap having a base with a diameter larger than the outer container of the dose cassette. The autoinjector device further include a housing for receiving the dose cassette, a clasp mechanism configured to hold the dose cassette within the housing, and an actuator configured to move the dose cassette proximally within the housing after the dose cassette is secured within the housing. The movement of the dose cassette causes the base of the needle cap to mechanically engage with a distal end of the housing, and the mechanical engagement between the base of the needle cap and the distal end of the housing causes the needle cap to separate from the dose cassette.

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.

A medication injection pen comprises a dose set knob rotatable with respect to a housing to set a desired injection dose. The dose set knob comprises at least one internal thread. A leadscrew includes a thread element for advancing in a first direction via a corresponding thread engagement. A driver is rotationally fixed to the leadscrew and is rotatable in a first direction to rotate and advance the leadscrew in the first direction. The setback member is rotationally fixed to the driver. The dose stop member is rotationally coupled to the setback member and is axially movable relative to the dose set knob when the dose set knob is rotated relative to the setback member. Axial movement of the dose stop member limits the user from setting a dose that is greater than an injectable volume of medication remaining in a cartridge.

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.