Abstract: The present disclosure is directed to a dose setting mechanism that may be used with a drug delivery device. The dose setting mechanism may include an inner body having a helical thread along an outer cylindrical surface of the inner body, and a drive sleeve for driving a piston rod in an axial direction, the drive sleeve positioned within at least a portion of the inner body. The dose setting mechanism may further include a dose dial sleeve rotatably engaged with the helical thread of the inner body and a dial grip connected to the dose dial sleeve and releasably connected to the drive sleeve. Further when a dose is set, the dial grip is rotated so that both the dose dial sleeve and the drive sleeve rotate with respect to the inner body.

Abstract: The present invention relates to a disposable auto injector that can be safely operated for automatic injection of a dose of medication and having a housing for accommodation of a syringe with a needle, the syringe being movably positioned in the housing between a first position in which position the needle is accommodated inside the housing and a second position in which position the needle protrudes outside the housing, a mechanical driver anchored to the housing at a first anchor location for applying a force to the syringe thereby moving the syringe from the first position to the second position, and wherein the mechanical driver is also configured for applying a force to the syringe by anchoring the mechanical driver to a different second anchor location.

Abstract: A dose reset mechanism for a medicament delivery device with a housing and a medicament container includes a dose setting member in the housing for setting a dose when it is rotated and for resetting the dose when it is rotated in the opposite direction. The dose setting member has a drive member connected to a plunger rod such that when the drive member rotates, the rod moves axially; and a connection member between the dose setting member and the drive member. A ratchet mechanism enables the connection member to rotate when the dose setting member rotates for setting a dose but not to move in the opposite direction. At least one dose reset member and at least one blocking member are connected to the ratchet mechanism such that the connection member and drive member are released when a dose knob is turned in the opposite direction.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A pen-type injector is improved so that a user may select a delivery dose of medicinal product from a multidose cartridge. The injector includes a housing, a cartridge containing medicinal product retained within a housing, a piston rod, a dose selecting member to select a dose of medicinal product to be expelled, and a drive member to expel the selected dose of medicinal product. The housing is formed unitary so that the dose selecting member and the drive member are moveably retained within the housing. The injector may include ratchet means associated with the insert to ensure the piston rod only rotates in a single direction through the insert, a button located on the drive sleeve, and clutch means which upon depression of the button prevents rotation between the dose dial sleeve and the drive sleeve.

Abstract: 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.

Abstract: 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.

Abstract: The invention relates to a gearing mechanism for a dose delivery device wherein the dose can be set by rotating a dose setting member (2, 102), and by which the dose setting member (2, 102) and a push-button (4) elevates from one end of the device proportional to the set dose from a position fixed relative to a housing (1, 101), and by which an injection of the set dose can be done by pressing the push-button back to its not elevated position, moving a piston rod (10, 110) cooperating with the piston in an cartridge (12, 112) and expelling a medicament out of the through a needle. The gearing mechanism is arranged in the device in such a way, that the loss of energy is very low.

Abstract: The present invention related to an injector is provided. The injector includes a case body, a dose setting, a first engagement, a second engagement, an elasticity element, and a button. The dose setting is used to preset a dose. The first engagement is connected with the dose setting. The elasticity element is connected between the first engagement and the second engagement. When the elasticity element is in an extension state, the first engagement and the second engagement are separated. When the button is pushed, the elasticity element is entered into a compress state to combine the first engagement and the second engagement, and then push the dose setting.

Abstract: A drive mechanism for a medication delivery device containing a resilient member and having a rotation member configured to be rotated in a first direction during setting of a dose of a medication and to be rotated in a second direction during delivery of the dose, where rotation member is coupled to a drive member that is coupled to a piston rod such that on dose delivery the piston rod is displaced in a distal direction to dispense a medicament and where the resilient member prevents movement of the drive member and the piston rod during dose setting.

Abstract: An injection device (1) for delivering a predetermined fixed dose of liquid drug, the device (1) comprising a base member, preferably a housing (2), a first tubular member (7) and a second tubular member (10). The first tubular member (7) and the base member are engaged via a first track (8) and a first protruding part (9), and the first tubular member (7) and the second tubular member (10) are engaged via a second track (11) and a second protruding part (12). The first track (8) comprises a first portion (8a) which the first protruding part (9) travels during setting of the predetermined fixed dose, and the second track (11) comprises a first portion (11a) which the second protruding part (12) travels during setting of the predetermined fixed dose.

Abstract: An injection device having a delivery element with an inner thread may be driven by rotation and includes a cylindrical outer wall region, which is substantially smooth. Such features provide a delivery element configured such that it is less intimidating to patients than known threaded rods, and may facilitate easy cleaning. The delivery element may be non-rotatably guided and axially spring-loaded, and may be inserted axially into the housing when the reservoir is replaced. The driving thread element for the delivery element may be mounted in the vicinity of the distal end of the housing.

Abstract: A medicament delivery device includes a body having a proximal end and a distal end, in turn comprising a distal housing part, and a medicament container holder, adapted to receive a medicament container; a dose setting drum for setting a dose when rotated in a first direction and for delivering a dose when rotated in a second direction, and a drive drum sleeve selectively operably connectable to a piston plunger for delivering a dose.

Abstract: An injection device for injection of set doses of medicine from a cartridge, in which one or more friction wheels engage linear bearing surfaces during dose setting and dose delivery.

Abstract: The present invention relates to a dispenser having an actuation device (24) for dispensing components from an output device that is connected to reservoirs (26, 27), wherein the actuation device acts on the pumping devices (34, 35) indirectly via a dosing device, and the dosing device is equipped with a setting device (23) that can be actuated to change the position of a transmission element (40) acting on the pumping devices for setting the quantity ratio, wherein both the setting device and the actuation device can be rotated about a longitudinal axis of the dispenser.

Abstract: A drive assembly suitable for a medication delivery device comprises a housing, a drive member, a piston rod, a rotation sleeve, a guide member and a biasing member. The rotation sleeve is arranged to be displaced in a distal direction when the drive member is displaced in the distal direction by mechanical interaction of the drive member and the rotation sleeve with the rotation sleeve and the drive member both being guided axially by the at guide member. The biasing member exerts a force on the rotation sleeve acting in the proximal direction, said force being transformed into a rotational movement of the rotation sleeve. The rotational movement of the rotation sleeve being transformed into a rotational movement of the piston rod.

Abstract: An assembly for a drug delivery device, comprising: a housing having a distal end and a proximal end, a piston rod, a drive member, the drive member being moveable in a proximal direction with respect to the housing and with respect to the piston rod for setting a dose of a drug, at least one stop member which is provided on one of the piston rod and the drive member and which is radially moveable with respect to the one of the piston rod and the drive member on which it is provided, and at least one interaction member which is provided on the other one of the piston rod and the drive member. Furthermore, a piston rod for a drug delivery device is provided.

Abstract: An injection device (1) for delivering a predetermined fixed dose of liquid drug, the device (1) comprising a housing (2), a first and second tubular members (7, 10). The first tubular member (7) and the housing are engaged via a first track (8) and a first protruding part (9), and the first and second tubular members (7, 10) are engaged via a second track (11) and a second protruding part (12). The first track (8) comprises a first portion (8a) which the first protruding part (9) travels during setting of the dose, and the second track (11) comprises a first portion (11a) which the second protruding part (12) travels during setting of the predetermined fixed dose. The first 10 portions (8a, 11a) of the first (8) and second (11) tracks are shaped in such a manner that the second tubular member (10) is prevented from rotating during setting 15 of a dose. The second tubular member (10) is rotationally locked to a piston rod (13), and rotation of the piston rod (13) during dose setting is thereby prevented.

Abstract: The present invention relates to drive mechanisms suitable for use in drug delivery devices, in particular pen-type injectors, wherein a number of pre-set doses of medicinal product can be administered. In particular, the present invention relates to such drug delivery devices where a user may activate the drug delivery device.

Abstract: A medical delivery system having a container and a dosing assembly, and wherein one of the container and the dosing assembly comprises a rotatable element adapted to engage the other one of the container and the dosing assembly. A container suitable for use in said medical delivery system. A dosing assembly suitable for use in said medical delivery system.

Abstract: An injection apparatus has a barrel (50) that is adapted to receive a container (108) with injection fluid (110). It further comprises a piston rod (98), provided with a thread (100), for expelling injection fluid (110) from such a container (108), which piston rod (98) is guided relative to the barrel (50) in the axial direction (112, 114). Additionally provided is a threaded part (122) whose thread (120) is in engagement with the thread (100) of the piston rod (98), which threaded part (122) is rotatable relative to the piston rod (98) and relative to the barrel (50) in order to set an injection dose, and, during an injection operation, is prevented from rotating relative to the piston rod (98).

Abstract: Some embodiments of a medical infusion pump system include a pump device having a flexible pushrod that can adjust from a curved configuration to a generally straight configuration. The flexible pushrod is part of a drive system of the pump device so that the flexible pushrod can be controllably and incrementally advanced toward a medicine reservoir to incrementally dispense the medicine therein. In particular embodiments, the flexible pushrod may comprise an anti-rotation mechanism, an anti-torsion mechanism, or a combination thereof.

Abstract: Some embodiments of a medical infusion pump system include a pump device having a flexible pushrod that can adjust from a curved configuration to a generally straight configuration. The flexible pushrod is part of a drive system of the pump device so that the flexible pushrod can be controllably and incrementally advanced toward a medicine reservoir to incrementally dispense the medicine therein. In particular embodiments, the flexible pushrod may comprise an anti-rotation mechanism, an anti-torsion mechanism, or a combination thereof.

Abstract: A one-time use device to deliver preservative-free follicle stimulating hormone (FSH) solution is disclosed. The device includes a needle covered by a sliding needle shield, which covers the needle in all modes of the device. The device can be placed into a ready-to-use position in four or fewer user steps. The device has a knob for setting a desired dose of FSH. The knob includes longitudinally spaced elements respectively corresponding to the lock position and the seven or fewer discrete dosing positions. The device locks after one use and cannot be reused thereafter.

Abstract: A medical delivery system comprising a container which is adapted to be fastened to a dosing assembly. One of the container and the dosing assembly comprises a rotatable element adapted to cooperate with the other one of the container and the dosing assembly, so as to lock/fasten the container to the dosing assembly. Furthermore, the present invention relates to a container and a dosing assembly for use in the medical delivery system.

Abstract: A dosing device for setting a dose to be delivered by an injection device, the dosing device including a setting element, e.g. a setting sleeve, and a drawing element, e.g. a rotating sleeve, which can be rotated out of the dosing device for preparing a dose delivery. A stop is on the setting element, and a counter stop is on the drawing element so that a rotational motion of the drawing element relative the setting element can be limited by the stops. The present invention encompasses a method for setting a dose that should be delivered by an injection device, wherein the dose to be delivered can be set by a setting element, e.g. a setting sleeve, and a drawing element of the injection device, e.g. a rotating sleeve, can subsequently draw up the dose by effecting a rotational motion to deliver the set dose from the injection device in a subsequent step. According to the present invention, the setting process is isolated from drawing process.

Abstract: The present invention relates to a drug delivery device for setting and dispensing of a dose of a medicament is presented comprising a housing to accommodate a cartridge filled with the medicament, an electrically operated drive mechanism to be operably engaged with the cartridge to expel a predefined dose of the medicament from the cartridge, and at least one dose element displaceably arranged relative to the housing to set and/or to dispense the dose of the medicament, wherein the dose element and the drive mechanism are mechanically decoupled from each other.

Abstract: The present invention relates to a medical delivery device comprising a housing (10); a medicament container (16) arranged to be placed in said housing; a stopper (18) movable within said container; a medicament dispensing means attachable to said housing and to said container through which medicament can be expelled; characterized in that the device further comprises a power unit (22) comprising a cover (24), a volute spring (26) arranged within said cover, and a pressure member (28) having a pressure pad (30) in contact with the stopper, a guide rod (34) extending into the volute spring and an annular ledge (32) in contact with the edges of the volute spring; activation means (36) mechanically connected to the cover and to the housing; and a spring locking means mechanically connected to said activation means, wherein said spring locking means (39) comprises a deformable ring-shaped member having (40) an inner diameter somewhat larger than the annular ledge, such that said ring-shaped member presents an ova

Abstract: A medical delivery system (100) having a container (102) and a dosing assembly (104), and wherein one of the container and the dosing assembly comprises a rotatable element (106) adapted to engage the other one of the container and the dosing assembly. A container suitable for use in said medical delivery system. A dosing assembly suitable for use in said medical delivery system.

Abstract: A device for delivering medicament includes a guide nut with guide ledges which cooperate with longitudinal grooves of a plunger rod for providing a rotational lock but allowing longitudinal movement of the plunger rod in relation to the guide nut that is rotationally locked to a distal housing part by engagement devices when the distal housing part and a proximal housing part are connected to each other. The device further includes a pressure release mechanism that includes slanting wedge-like surfaces arranged on the drive nut and slanting wedge-like surfaces arranged on a fixed inner annular surface of the distal housing part, which slanting wedge-like surfaces abut each other such that they move out of contact near the end of delivery of a predetermined quantity of medicament when the drive nut is rotated.

Abstract: An injection control device (ICD) for a syringe, injects/extracts material into/from at a rate controllably proportional to the rate of movement of the syringe. A transmission reference member is extendable outward from the ICD body, being connected to a transmission system/clutch which has an engage/disengage trigger for independent movement of a plunger arm. The ICD, via the transmission translates motion from movement of the body, in relation to a fixed state of the transmission reference member, to action on the plunger of an accommodated syringe. The clutch also allows the transmission reference member to be positioned, without transferring power to the transmission system.

Abstract: A medical delivery system (100) comprising a container (102) which is adapted to be fastened to a dosing assembly (104). One of the container and the dosing assembly comprises a rotatable element (106) adapted to cooperate with the other one of the container and the dosing assembly, so as to lock/fasten the container to the dosing assembly. Furthermore, the present application relates to a container and a dosing assembly for use in the medical delivery system.

Abstract: The present invention relates to a dose setting and expelling device comprising a drive member and a dose setting mechanism which simultaneously sets a given dose and stores the energy necessary for a subsequently driving the drive member in order to expel a dose of medicine from an injection device. According to the invention the dose setting mechanism allows adjustment in both directions, such that a given set dose can be reduced or cancelled by reversing the input motion, typically by rotating a setting member backwardly, this in contrast to the known devices which either requires an additional release mechanism or which cannot be reversed at all.

Abstract: The present invention relates to an electronically assisted injection device adapted to inject doses of a drug from a held cartridge. The injection device may include a first rotational sensor (40) coupled to a driver (6) for sensing a dose setting and a second rotational sensor (50) coupled to a dosing member (8) for sensing an expelled dose. A third axial sensor (60) provides information relating to the axial position of the driver (6). A control circuit is adapted to determine the end of dosed state based on data from the first, the second and the third sensors (40, 50, 60). The injection device may also include an arrangement for determining fluid ingress into the interior of the injection device. The arrangement includes an electrically non-conductive surface portion (63) disposed on a first component (6) and an electrode assembly (62a, 62b, 62c) disposed on a second component (80) wherein the first component (6) and the second component (80) moves relative to each other during operation.

Abstract: The present disclosure is directed to a dose setting mechanism that may be used with a drug delivery device. The dose setting mechanism may include an inner body having a helical thread along an outer cylindrical surface of the inner body, and a drive sleeve for driving a piston rod in an axial direction, the drive sleeve positioned within at least a portion of the inner body. The dose setting mechanism may further include a dose dial sleeve rotatably engaged with the helical thread of the inner body and a dial grip connected to the dose dial sleeve and releasably connected to the drive sleeve. Further when a dose is set, the dial grip is rotated so that both the dose dial sleeve and the drive sleeve rotate with respect to the inner body.

Abstract: The present invention relates to a medication delivery device, to dosing mechanisms suitable for use in such medication delivery device, in particular in pen-type injectors, preferably having a dose setting member and a drive device enabling the dose setting and the administration of a medicinal product from a multi-dose medication cartridge, to methods using such device, and to methods of manufacturing and assembly of such device.

Abstract: An autoinjector device comprises a drive housing 10 and a syringe housing 12 which can be disconnected to allow insertion of a syringe. A drive mechanism in the drive housing is cocked by means of a cord 8 connected between the drive housing and the syringe housing. The drive mechanism comprises a drive gear 22 rotatably mounted in the drive housing and acting as a rotary crank connected by a connecting rod 26 to a plunger 28. In use the drive gear 22 is driven by a torsion spring 35 so that the drive mechanism extends the syringe from the syringe housing and expels a dose and then retracts the syringe back into the housing. A firing button 14 releases the drive gear to be driven by the torsion spring but is also engageable as a brake on the rim of the drive gear.

Abstract: The present invention relates to a medication delivery device, to dosing mechanisms suitable for use in medication delivery devices, in particular in pen-type injectors, preferably having dose setting means and a drive device enabling the administration of a medicinal product from a single- or multi-dose medication cartridge, to a use of such device, and to a method of manufacturing or assembling such device.

Abstract: The present invention relates to an injection device for administering doses of liquid drug. The injection device comprises a user operable dose adjustment structure configured to adjust, in a prepared state of the device, a dose of liquid drug of a first size to set a dose of a second size. The present injection device is particularly suitable for self-injection of liquid drugs such as insulin for treating diabetes by the user or patient.

Abstract: An injection device for injection of set doses of medicine from a cartridge has a nut that is screwed up along a threaded piston rod during a dose setting operation. The nut is screwed along the piston rod by rotating a dose setting member. A rotational coupling mechanism includes an axially displaceable coupling member which is rotated as a function of axial displacement. During dose setting, the nut is allowed to rotate relative to the coupling member. During injection, the coupling member is rotationally locked to the nut. This provides a dose setting and injection mechanism wherein the nut member is both rotated during dose setting and during injection.

Abstract: An auto-injection device has a housing with a medicament container disposed within; a dose setting mechanism for setting a dose of a medicament; a drive nut and a plunger rod operably connected, with an energy accumulator operably connected to the dose setting mechanism; and an activating mechanism and a positioning mechanism operably connected to the plunger rod for locking the plunger rod from being displaced. The positioning mechanism includes a locking nut arranged to cooperate with fixed, flexible locking features for locking the locking nut from rotation. A resilient member arranged inside the plunger rod is configured to allow the plunger rod to be resiliently and axially displaced when the locking nut is unlocked.

Abstract: A medical delivery system comprising a container (202) for accommodation of a medicament and a dosing assembly (204) adapted to be fastened to the container. The medical delivery system comprises a coding mechanism for ensuring that only a predetermined container can be fastened to a predetermined dosing assembly. A container for use in the medical delivery system. A dosing assembly for use in the medical delivery system.

Abstract: A resettable drug delivery device is provided comprising a body, a cartridge holder for receiving a cartridge, and means for releasably coupling the cartridge holder to the body or the dose setting mechanism. During an initial rotational coupling movement of the cartridge holder relative to the body or the dose setting mechanism the cartridge holder is caused to move in a first axial direction relative to the body or the dose setting mechanism and during a continued rotational coupling movement of the cartridge holder relative to the body or the dose setting mechanism the cartridge holder is caused to move in a second, contrary axial direction.

Abstract: The present invention relates to a device for the delivery of predetermined doses of liquid medicament to a patient, which medicament is intended to be inhaled by the patient or intended to be injected into the body of the patient. The device is adapted to be in a medicament delivery state and in a medicament non-delivery state. When the device is in a medicament delivery state, said device is adapted to drive a piston into a cartridge containing the liquid medicament to be delivered, with a force that is above or equal to a predetermined minimum force value and below a predetermined maximum force value. The minimum force value is the lowest force value needed to deliver the predetermined dose and the maximum force value is the first force value at which it exists a risk of damaging the cartridge or the components of the device. Further, more of the spring force is brought to an efficient output torque ensuring that a predetermined volume of medicament is expelled from a cartridge.

Abstract: A medical delivery system wherein one of a container and a dosing assembly comprises a first fastening means (116) and the other one of the container and the dosing assembly comprises a second fastening means (114); and wherein the second fastening means is adapted to move at least a part of the first fastening means in a radial direction upon rotation of the container in a first rotational direction relative to the dosing assembly, whereby the first and second fastening means engage such that the container and the dosing assembly are locked for relative translational movement. A container and a dosing assembly for use in the medical delivery system.

Abstract: The present invention relates to a medicament delivery device comprising an elongated housing arranged to contain a medicament container which medicament container contains a number of doses; a dose counter mechanism comprising a dose drum arranged with dose indicia on its outer surface and visible through a window on said housing; a rotatable driver connected to said dose drum; a plunger rod arranged to act on said medicament container for expelling a dose of medicament; an actuation mechanism connected to said rotatable driver and to said plunger rod when said medicament delivery device is actuated; wherein said dose drum is arranged with internal threads, in engagement with corresponding threads on said driver, wherein said threads have a certain pitch; wherein said dose drum is also arranged with external threads in engagement with corresponding threads arranged fixed in relation to said housing, wherein said threads have a certain pitch; and wherein the pitch of the threads between the dose drum and fixe

Abstract: The invention concerns an injection device for apportioning set doses of a drug from a reservoir to a subject. The injection device comprises a dose setting member (20, 70) which is screwed out from the housing (30) to set a dose and pushed axially back to the housing (30) in order to expel the set dose. A scale drum (80) is axially and inrotatable coupled to the dose setting member (20, 70) such that the scale drum (80) is rotated up a thread (34) when the dose setting member (20, 70) is rotated to set a dose. When the dose setting member (20, 70) is pushed axially back to its initial position to inject the set dose, the scale drum (80) is released from its inrotatable connection in order to allow the scale drum (80) to rotate down the thread (34) and back to its zero position.