A drive mechanism for a drug delivery device with a reduced operating loudness includes a dose selector, a housing, and a ratchet with a gear element comprising a plurality of gear teeth connected with the dose selector and a pawl element rotationally constrained to the housing comprising at least one pawl tooth. The at least one pawl tooth engages with the gear teeth and is located opposite to the gear teeth. One of the gear element and the pawl element moves forth and back relative to the other element of the gear and pawl elements along a first direction for de-engagement and re-engagement of the opposite gear teeth and at least one pawl tooth when the gear element rotates relative to the housing during dose setting using the dose selector. The pawl element and/or gear element comprises a noise reduction characteristic at a surface which dampens the noise produced

A drive mechanism for a medicament delivery device is disclosed having a housing with a proximal end and a distal end, a container carrier arranged within the housing and being axially movable in relation to the housing, and a drive assembly partially arranged within the housing and being axially movable in relation to the housing. The drive assembly has a proximally extended rack arm, a cogwheel arranged within the housing and being rotatable but axially fixed in relation to the housing, wherein the cogwheel is selectively coupled to the rack arm through a tangential engagement with a first set of rack teeth or a second set of rack teeth which are arranged on the rack arm and wherein the first set of rack teeth or the second set of rack teeth forces the cogwheel to rotate when the drive assembly is axially moved towards the proximal end in relation to the housing. The cogwheel further has a connecting member configured to connect to a counter connecting member which is arranged on the container carrier; such that a rotational movement of the cogwheel is converted into a linear movement of the container carrier.

A pushing unit is stopped just before abutting against a rear end of a syringe to reliably prevent unwanted extrusion of a chemical liquid from a syringe. An injecting apparatus for injecting a chemical liquid includes: an injection head to which a syringe filled with the chemical liquid is to be mounted; a pushing unit provided on the injection head and pushing a rear end of the syringe; a rear end detection unit provided on the injection head and detecting the rear end in a contactless manner; and a control unit configured to control the injection head, the control unit acquiring a forward movement distance that the pushing unit is to be moved forward after the rear end is detected, and causing the pushing unit to move forward by the forward movement distance after the rear end is detected and to stop at a position separated from the rear end.

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.

A 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 to move a piston within a container. A medical delivery device for advancing a piston in a medicament container to expel a medicament can include such drive assembly.

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.

A modular drive train is selectively securable within a wearable injector. The drive train includes a chassis and a telescoping driving assembly mounted within the chassis. The driving assembly includes a first shaft rotatable relative to the chassis, and a second shaft connected with the first shaft and axially movable relative thereto. Rotation of the first shaft axially drives the second shaft. The chassis includes one of a bearing and an elastically expandable collar projecting axially forward into the chassis from a rear end thereof, and the first shaft includes the other of the bearing and the elastically expandable collar projecting axially rearwardly from a rear end thereof. The collar is configured to elastically snap over an interference element of the bearing, whereby engagement of the collar with the bearing axially secures the first shaft to the chassis and permits rotation of the first shaft about the bearing.

An automatic injection control device injects fluid at a rate directly related to the displacement rate of the device body from a held positioning member. The device has a syringe end, a gripping end, a syringe barrel coupled to the body and a refillable reservoir and at least one directional valve at the syringe end of the body. The directional valves permitting refilling of the refillable reservoir without removing the syringe barrel. Also, a transmission system is coupled to the body, as well as the positioning member, a syringe plunging member, and a gearing mechanism linking the positioning member to the syringe plunging member. The device is designed so that when the positioning member is held in a fixed extended position and the body is pulled by the gripping end, the transmission system provides a one-way motion of the syringe plunging member to precisely inject fluid from the device.

An automatic administration instrument includes a syringe and a partition wall in the syringe which partitions the syringe into different rooms for respectively holding plural kinds of drug solutions or a drug and a drug solution. A partition-wall driver displaces the partition wall and an injection needle is connected to the syringe. A body cap attached to the administration instrument body so as to cover the injection needle. The syringe, the partition wall, and the body cap are configured such that displacing the partition wall dissolves or mixes the drug solutions or the drug and the drug solution in a state that the injection needle is covered by the body cap.