A drug delivery device comprises a housing (201) and an expelling assembly with a piston rod (220), a drive tube (260) with an outer surface and a scale drum (270) arranged between the drive tube and the housing, the scale drum being coupled to the housing and the drive tube outer surface. The device further comprises a drive spring (255) arranged between the housing and the drive tube, and setting means (280) allowing a user to simultaneously set a dose amount to be expelled and strain the drive spring correspondingly by rotation of the drive tube. The scale drum is coupled to the drive tube via a spline connection, wherein the drive spring is arranged proximally of the spline connection when the spline connection is in its proximal-most position.

A medicament injection device comprising: a main body configured to receive a medicament cartridge, a needle sleeve axially movable with respect to the main body, a needle holder holding a needle, and a displacement element coupled to the needle holder and disengageably coupled to the needle sleeve; wherein, upon axial displacement of the needle sleeve by a predefined distance in a proximal direction, the needle carrier and needle are displaced axially in a proximal direction.

A dispensing mechanism for delivering a dosage of medicament including a housing having a proximal-distal axis; a plunger rod having a screw thread and configured to advance along the proximal-distal axis relative to the housing; a user-operable push button moveable along the proximal-distal axis relative to the housing; a twist driver threadably engaged with the push button such that movement of the push button towards the distal end of the housing causes rotation of the twist driver about the proximal-distal axis; and a driver engaged with the twist driver such that rotation of the twist driver causes rotation of the driver, the driver also engaged with a portion of the plunger rod such that rotation of the driver causes rotation of the plunger rod, advancing the plunger rod along the proximal-distal axis relative to the housing.

A dispensing mechanism for delivering a dosage of medicament including a housing having a proximal-distal axis; a plunger rod having a screw thread and configured to advance along the proximal-distal axis relative to the housing; a user-operable push button moveable along the proximal-distal axis relative to the housing; a twist driver threadably engaged with the push button such that movement of the push button towards the distal end of the housing causes rotation of the twist driver about the proximal-distal axis; and a driver engaged with the twist driver such that rotation of the twist driver causes rotation of the driver, the driver also engaged with a portion of the plunger rod such that rotation of the driver causes rotation of the plunger rod, advancing the plunger rod along the proximal-distal axis relative to the housing.

A medicament delivery device (IO) is presented having a housing and a medicament container holder arranged movable in relation to the housing and capable of accommodating a medicament container. The device also has an activator having a plunger rod arranged to be moved in the proximal direction of the medicament delivery device by the activator to act on a stopper in the medicament container for delivering a dose of medicament through a medicament delivery member when the activator is operated. A delay mechanism is also arranged between the activator and the plunger rod, which is provided with delay elements allowing movement of the activator in the proximal direction after movement of the plunger rod has terminated.

A device for administering a fluid product, the device including a first housing part provided with a receiver for the product, a second housing part detachably connectable to the first housing part, a piston rod held such that it can be displaced for the exertion of an emptying movement, an actuatable or releasable drive element for the piston rod, a coupling element including a coupling input element that couples the drive element to the piston rod in a coupling engagement, transmits a driving force of the drive element to the piston rod, and triggers the emptying movement, and a decoupling element displaceably connected to the second housing part and coupled to the first housing part such that it is displaced, by a movement of the housing parts in relation to each other when the housing parts are separated into a decoupling position wherein the piston rod is decoupled from the coupling input element.

An assembly for a drug delivery device is presented. The assembly comprises a housing and a piston rod having a longitudinal axis, a distal end and a proximal end. The piston rod further comprises a piston rod interaction feature, and a piston rod guide being movable with respect to the piston rod, the piston rod guide further comprising a guide interaction feature corresponding to the piston rod interaction feature, the piston rod guide being movable with respect to the piston rod to switch between a first state and a second state of the assembly, the second state being different from the first state. The assembly is configured such that, in a first state of the assembly, the piston rod guide is in a first axial position relative to the piston rod in which the piston rod interaction feature is arranged to interact with the guide interaction feature to prevent proximal movement of the piston rod with respect to the housing, and wherein, in a second state of the assembly being different from the first state, the piston rod guide is in a second axial position relative to the piston rod, the second axial position being different from the first axial position, wherein, in the second axial position, the piston rod interaction feature and the guide interaction feature are arranged such that proximal movement of the piston rod with respect to the housing is allowed.

Disclosed is an infusion device drive unit that includes a pump drive configured to operatively mechanically couple to a dosing unit to control operation of the dosing unit. The infusion device drive unit further includes a blocking member that is movable between a blocking configuration and a enabling configuration, the blocking member enabling the establishing and/or the releasing of an operative mechanical coupling between the pump drive and the dosing unit in the enabling configuration and preventing the establishing and/or the releasing of an operative mechanical coupling between the pump drive and the dosing unit in the blocking configuration. The infusion device drive unit controls the blocking member to take on the enabling configuration if the pump drive is in at least one pre-determined configuration and to take on the blocking configuration if the pump drive is in a configuration different from a pre-determined configuration.

The present invention refers to a metering mechanism for an injection device. The mechanism comprises an actuating element (1) for setting or discharging a dose from the injection device, a piston rod (2) for producing an advance movement for dispensing a dose, a piston rod sleeve (3) in which the piston rod (2) is accommodated such that the piston rod (2) can be non-rotatably connected to the piston rod sleeve (3), and a coupling element (4) with which the actuating element (1) and the piston rod sleeve (3) can be coupled for discharge of the dose set with the actuating element (1) in such a way that a dispensing movement of the actuating element (1) is transmitted to the piston rod (2) by way of the piston rod sleeve (3) connected to the piston rod (2). To prevent underdosage, the piston rod (2) comprises a stop (2c) and the coupling element (4) comprises a counter-stop (4e) which move relative to each other at least during setting of a dose and which abut each other in a maximum dose stop position, thereby preventing further setting of a dose. Further, the present invention refers to an injection device with such a metering mechanism.

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.