CN118103098A - Method of assembling a medicament delivery device - Google Patents

Abstract

A method of assembling a medicament delivery device, the method comprising: providing a housing of a medicament delivery device; wherein the housing extends along a longitudinal axis between a proximal end and a distal end; providing a power unit of the medicament delivery device; wherein the power unit comprises a plunger rod and a holder engaged with the plunger rod; assembling the power unit into the housing; providing a cap assembly extending along a longitudinal axis between a proximal end and a distal end; connecting the cap assembly to the plunger rod or the holder; and moving the cap assembly relative to the housing in a distal direction of the housing until the cap assembly is attached to the proximal end of the housing, wherein during the step of moving the cap assembly relative to the housing, the cap assembly moves the plunger rod relative to the holder.

Description

Method of assembling a medicament delivery device

Technical Field

The present disclosure relates generally to a method of assembling a medicament delivery device, and in particular to a method of assembling a medicament delivery device comprising the step of attaching a cap assembly to a housing.

Background

Medicament delivery devices such as auto-injectors, inhalers and on-body devices are generally known for self-administration of medicament by patients without formal medical training. Thus, these medicament delivery devices typically include a number of automated functions and are typically delivered to the end user with pre-filled medicament containers. Medicament containers typically comprise a glass or plastic cartridge having a stopper sealed at its rear end and a delivery member disposed on its front end or a pierceable membrane disposed on its front end. Some pre-filled medicament containers also contain a quantity of air due to the medicament container filling process and/or the nature of the medicament contained. Therefore, it is necessary to perform a priming injection prior to the medicament delivery operation. In addition, some medicament containers contain substances that need to be mixed prior to a medicament delivery operation.

It has been appreciated that an improved solution for providing a priming injection prior to a medicament delivery operation would be useful. It will also be appreciated that a new method of assembling the medicament delivery device would be beneficial.

Disclosure of Invention

The invention is defined by the appended claims, to which reference should now be made.

In the present disclosure, when the term "distal direction" is used, this means pointing away from the dose delivery site during use of the drug delivery device. When the term "distal portion/end" is used, this refers to the portion/end of the delivery device or the portion/end of a member thereof which is located furthest away from the dose delivery site when the drug delivery device is used. Accordingly, when the term "proximal direction" is used, this refers to the direction pointing to the dose delivery site during use of the drug delivery device. When the term "proximal portion/end" is used, this refers to the portion/end of the delivery device or the portion/end of the member thereof which is located closest to the dose delivery site when the drug delivery device is used.

Furthermore, the terms "longitudinal", "longitudinally", "axially" or "axial" refer to a direction extending from a proximal end to a distal end, typically along the device or component thereof in the longest direction of extension of the device and/or component.

Similarly, the terms "transverse", "transverse" and "transversely" refer to directions substantially perpendicular to the longitudinal direction.

Furthermore, the term "circumferential", "circumferential" or "circumferentially" refers to a circumferential or circumferential direction relative to an axis, which is typically a central axis extending in the longest direction of extension of the device and/or component. Similarly, "radial" or "radially" refers to a direction extending radially relative to an axis, and "rotating", "rotating" and "rotationally" refer to rotation relative to an axis.

Accordingly, there is provided a method of assembling a medicament delivery device, the method comprising: providing a housing of a medicament delivery device; wherein the housing extends along a longitudinal axis between a proximal end and a distal end; wherein, during use of the medicament delivery device, the distal end of the housing is directed away from the medicament delivery site; and wherein during use of the medicament delivery device, a proximal end of the housing is directed towards the medicament delivery site; providing a power unit of the medicament delivery device; wherein the power unit comprises a plunger rod and a holder engaged with the plunger rod; assembling the power unit into the housing; providing a cap assembly extending along the longitudinal axis between a proximal end and a distal end; connecting the cap assembly to the plunger rod or the holder; and moving the cap assembly relative to the housing in a distal direction of the housing until the cap assembly is attached to a proximal end of the housing, wherein during the step of moving the cap assembly relative to the housing, the cap assembly moves the plunger rod relative to the housing when the cap assembly is connected to the plunger rod; or the retainer moves relative to the housing when the cap assembly is connected to the retainer.

Another aspect of the invention provides a method of assembling a medicament delivery device, the method comprising: providing a housing of a medicament delivery device; wherein the housing extends along a longitudinal axis between a proximal end and a distal end; providing a power unit of the medicament delivery device; wherein the power unit comprises a plunger rod and a holder engaged with the plunger rod; assembling the power unit into the housing; providing a cap assembly extending along the longitudinal axis between a proximal end and a distal end; connecting the cap assembly to the plunger rod or the holder; and moving the cap assembly relative to the housing in a distal direction of the housing until the cap assembly is attached to the proximal end of the housing, wherein during the step of moving the cap assembly relative to the housing, the cap assembly moves the plunger rod relative to the holder.

Preferably, according to another embodiment, the method further comprises the step of, prior to connecting the cap assembly to the plunger rod or the holder:

Providing a medicament container; and inserting the medicament container into the housing from the proximal end of the housing.

Preferably, according to another embodiment, before assembling the power unit into the housing, the method further comprises the steps of: providing a conveying member shield; and assembling the conveying member shield and the power unit into the housing.

Preferably, according to another embodiment, the method further comprises the steps of: the transport member shield is engaged to the holder either before or after the transport member shield and the power supply unit are assembled into the housing.

Preferably, according to another embodiment, the step of moving the plunger rod relative to the housing comprises moving the plunger rod relative to the holder while the holder is not movable relative to the housing.

Or according to another embodiment, the step of moving the plunger rod relative to the holder comprises moving the plunger rod relative to the holder while the holder is not movable relative to the housing.

Preferably, according to a further embodiment, the plunger rod is not movable relative to the housing during the step of moving the holder relative to the housing.

Or according to another embodiment, the step of moving the plunger rod relative to the holder comprises moving the holder relative to the plunger rod while the plunger rod is not movable relative to the housing.

Preferably, according to a further embodiment, the step of connecting the cap assembly to the plunger rod comprises the step of bringing the proximal end of the medicament container into contact with the cap assembly from the distal end of the cap assembly.

Preferably, according to another embodiment, the step of moving the plunger rod relative to the holder comprises the steps of: moving the medicament container in a distal direction relative to the housing using the cap assembly; bringing the proximal end of the plunger rod into contact with the distal end of the medicament container; moving the plunger rod in a distal direction relative to the housing using the distal end of the medicament container; disengaging the plunger rod from the holder by moving the plunger in a distal direction relative to the housing; and attaching a cap assembly to the proximal end of the housing.

Preferably, according to another embodiment, the step of connecting the cap assembly to the holder comprises the step of moving the cap assembly in a proximal direction relative to the delivery member shield such that the cap assembly contacts the proximal end of the delivery member shield.

Preferably, according to another embodiment, the step of moving the plunger rod relative to the holder comprises the steps of: moving the delivery member shield in a distal direction relative to the housing using the cap assembly; moving the holder relative to the plunger rod with distal movement of the delivery member shield; and attaching a cap assembly to the proximal end of the housing.

Preferably, according to a further embodiment, the step of moving the holder relative to the plunger rod comprises the step of rotating the holder relative to the plunger rod by distal movement of the delivery member shield.

Preferably, according to a further embodiment, the step of moving the holder relative to the plunger rod comprises the step of linearly moving the holder relative to the plunger rod in a direction transverse to the longitudinal axis by means of a distal movement of the delivery member shield.

Preferably, according to another embodiment, when the cap assembly is attached to the proximal end of the housing, the cap assembly is moved axially relative to the housing towards the distal end of the housing until the cap assembly is snap-fitted to the housing.

Preferably, according to another embodiment, the medicament delivery device is functionally completed after the cap assembly is attached to the proximal end of the housing.

Preferably, according to another embodiment, the medicament delivery device is an injection device, an inhalation device or a medical nebulizer.

In general, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a/an/the element, device, component, means, etc" are to be interpreted openly as referring to at least one instance of the element, device, component, means, etc., unless explicitly stated otherwise.

Drawings

Embodiments of the inventive concept will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1A schematically shows a perspective view of a medicament delivery device.

Fig. 1B schematically illustrates a cross-sectional view of a rear sub-assembly of the medicament delivery device of fig. 1A.

Fig. 2A schematically illustrates a perspective view of components of the rear subassembly of fig. 1B.

Fig. 2B schematically illustrates a perspective view of components of a cap assembly of the medicament delivery device of fig. 1A.

Fig. 2C schematically illustrates a perspective view of the cap assembly of fig. 2B without the cover.

Fig. 2D schematically illustrates a cross-sectional view of the cap assembly of fig. 2B.

Fig. 3A schematically illustrates a cross-sectional view of the plunger rod of the rear sub-assembly of fig. 1B, the plunger rod spring of the rear sub-assembly of fig. 1B, and the holder of the rear sub-assembly of fig. 1B.

Fig. 3B schematically shows a cross-sectional view of the plunger rod of fig. 3A and the holder of fig. 3A.

Fig. 3C schematically illustrates a perspective view of the holder of fig. 3A and the transport member shield of the rear subassembly of fig. 1B.

Fig. 4A schematically illustrates a side view of the rear sub-assembly of fig. 1B and the hood assembly of fig. 2B.

Fig. 4B-C schematically illustrate perspective views of the holder of fig. 3A and the delivery member shield of the rear subassembly of fig. 1B.

Fig. 4D schematically shows a cross-sectional view of the plunger rod of fig. 3A and the holder of fig. 3A.

Fig. 5A schematically illustrates a perspective view of the rear subassembly of fig. 1B without the delivery member shield and the medicament container.

Fig. 5B schematically illustrates a cross-sectional view of a distal portion of the rear sub-assembly of fig. 5A.

Fig. 6A schematically illustrates a cross-sectional view of the headgear assembly of fig. 2B.

Fig. 6B schematically shows a perspective view of the medicament delivery device.

Fig. 6C schematically illustrates a cross-sectional view of a distal portion of the rear sub-assembly of fig. 6B.

Detailed Description

Fig. 1A-6C show a medicament delivery device that will be used to describe the assembly method. The medicament delivery device comprises a rear sub-assembly 1, a cap assembly 2 and a medicament container 3. The rear sub-assembly 1 is the power pack of the medicament delivery device. The power pack is configured to expel a medicament contained within a medicament container 3 of the medicament delivery device when the medicament delivery device is in use. In a preferred example, the medicament delivery device is an automatic injector comprising an automatic function of priming and/or mixing substances from multiple chambers within a single medicament container. Or the medicament delivery device may be an inhalation device or a medical nebulizer.

As shown in fig. 1B and 2A, the rear subassembly 1 includes a housing 10 extending along a longitudinal axis L between a proximal end and a distal end, a plunger rod 11, a weighted plunger rod spring 12 engaged with the plunger rod 11, a retainer 13, and a delivery member shield 14 telescopically arranged relative to the proximal end of the housing 10. As defined above, during use of the medicament delivery device, the distal end of the housing 10 is directed away from the medicament delivery site; and wherein during use of the medicament delivery device, the proximal end of the housing 10 is directed towards the medicament delivery site. The rear sub-assembly 1 further comprises a delivery member shield biasing member 15, the delivery member shield biasing member 15 being arranged between a distally directed surface of the delivery member shield 14 and a proximally directed surface of the housing 10; optionally, a guide rod 17 is positioned within the plunger rod spring 12. The housing 10 optionally includes a medicament container holder 16 secured to the housing 10. The medicament container holder 16 is configured to at least partially enclose the medicament container 3. The housing 10 also includes fasteners configured to engage the headgear assembly 2 during assembly. The fastener may be arranged on a wall of the housing; or in the example where the housing 10 includes the medicament container holder 16, the fastener 16a may be disposed on a wall of the medicament container holder 16.

The plunger rod 11, the force plunger rod spring 12 and the holder 13 are all arranged within the housing 10. In the example where the rear subassembly includes the transport member shield biasing member 15 and the guide bar 17, both the transport member shield biasing member 15 and the guide bar 17 are disposed within the housing 10. In examples where the housing 10 includes a medicament container holder 16, the medicament container holder 16 is also disposed within the housing 10. The stressed plunger rod spring 12 is engaged with the plunger rod 11 at one end and with the housing 10 at the other end, e.g. directly or indirectly, such that the stressed plunger rod spring 12 is configured to actuate the plunger rod 11 in a proximal direction of the housing 10 after the rear sub-assembly 1, the cap assembly 2 and the medicament container 3 are assembled together for expelling a medicament contained within the medicament container 3. When the plunger rod 11 is in a starting position relative to the holder, the holder 13 is configured to releasably hold the plunger rod 11 against the biasing force from the plunger rod spring 12. As shown in fig. 3B, plunger rod 11 includes a proximally directed retaining surface 11a that engages a distally directed opposing retaining surface 13a of holder 13; and the distally directed counter holding surface 13a is substantially perpendicular to the longitudinal axis L. In one example, the plunger rod spring 12 is at least partially disposed within the plunger rod 11, as shown in fig. 3A. In another example, the plunger rod spring surrounds at least a portion of the plunger rod. In one example, the holder 13 is a rotatable member rotatable about the longitudinal axis L relative to the plunger rod 11. The swivel comprises a generally tubular body, and a ledge (or alternatively, a recess or cutout) arranged on a surface of the tubular body for defining a distally directed counter-holding surface 11a. In another example, the retaining member is a slide member that is linearly movable relative to the plunger rod in a direction transverse to the housing. The holder comprises a generally tubular body and a ledge (or alternatively, a recess or cutout) arranged on a surface of the wall for defining a distally directed counter-holding surface. The holder 13 is configured to be connected to a trigger of the medicament delivery device and to release the plunger rod from the initial position by movement of the trigger such that the plunger rod moves in the proximal direction of the housing under the biasing force from the plunger rod spring, thereby expelling the medicament contained by the medicament delivery device. For example, when the medicament delivery device is configured to be activated by movement of the delivery member shield 14 (the delivery member shield acting as a trigger), the holder is then connected to the delivery member shield; in another example, the holder is then connected to the button when the medicament delivery device is configured to be activated by movement of the button, e.g. a thumb button (thumb button acting as a trigger).

The hood assembly 2 includes a cover 20 extending along a longitudinal axis L between a proximal end (closed end) and a distal end (open end). The cover 20 is configured to cover the medicament delivery member prior to a medicament delivery operation, i.e. prior to use of the medicament delivery device, e.g. to cover the needle of the medicament delivery device when the medicament delivery device is a syringe. The cap 20 is configured to be at least partially attached to the medicament delivery device when the medicament delivery member is arranged at the proximal end of the medicament delivery device. In a preferred example, the cap is configured to cover the needle. In a preferred example, the cap 20 includes a sleeve-shaped body extending between a proximal end and a distal end. Or the cap comprises a flat button-shaped body, in this example the medicament delivery member is mainly accommodated within the housing of the medicament delivery device, whereby the cap is configured to cover the proximal tip of the medicament delivery device. In one example, the cap assembly includes a transport member shield remover disposed within the cover. In examples where the medicament delivery device is an automatic injector having a medicament container including a rigid needle shield and/or a flexible needle shield, the delivery member shield remover of the cap assembly is configured to fixedly engage with at least one of the rigid needle shield and the flexible needle shield of the medicament container. In this example, the medicament container is a syringe (medicament container with an integral needle or nozzle thereon). In another example, as shown in fig. 2B-D, the headgear assembly 2 includes a cover and base 23, and optionally a delivery member 21 and a delivery member holder 22. The transport member 21, transport member holder 22, and base 23 are all at least partially disposed within the cover 20 and are all movable relative to the cover 20. The conveying member 21 is fixed to the conveying member holder 22. The delivery member 21 includes a distal tip and a proximal delivery end. In this example, the medicament container 3 is a cartridge (a medicament container without an integral needle or nozzle on the medicament container). The distal shaped end of the delivery member 21 is configured to penetrate the proximal seal of the medicament container 3 when activated in order to establish fluid communication between the medicament container and the proximal delivery end of the delivery member 21. The proximal delivery end of the delivery member 21 is configured to deliver the contained medicament to an end user. For example, the proximal delivery end of delivery member 21 may be a needle or nozzle. The base 23 includes a proximal portion 23a, a distal portion 23b, and opposing fasteners 23c. The delivery member holder 22 and the delivery member 22 are received within a proximal portion of the base 23. The counter-fastener 23c is configured to engage with the fastener 16 of the housing 10 during assembly of the medicament delivery device. In the preferred example, the fastener 16a and the counter fastener 23c form a snap-fit engagement. In a preferred example, when the cap assembly 2 comprises a delivery member 21 and a delivery member holder 22, the establishment of fluid communication between the medicament container and the proximal delivery end of the delivery member 21 is activated by removing the cover 20. On the other hand, in examples where the cap assembly 2 does not include the delivery member 21 and the delivery member holder 22, the end user may establish fluid communication between the medicament container and the delivery member by attaching the delivery member (e.g., attaching a pen needle).

It should be noted that the description of the present invention does not explain in detail how the fluid communication between the medicament container and the proximal delivery end of the delivery member is activated by removing the cap, as there are many different ways to activate the fluid communication between the medicament container and the proximal delivery end of the delivery member (see for example the disclosure of WO 2009150078), and how the fluid communication between the medicament container and the proximal delivery end of the delivery member is activated is not part of the present invention. Similarly, the description of the present invention will not explain in detail how to trigger a medicament delivery operation (fully releasing the plunger rod from the holder) as there are many different ways of triggering a medicament delivery operation (see e.g. WO 2006057604) and how to trigger a medicament delivery operation is not part of the present invention.

The method of the invention comprises the following steps: providing a housing 10 of a medicament delivery device; and providing a power unit of the medicament delivery device. The power unit comprises a plunger rod 11 and a holder 13 engaged with the plunger rod 11. The power unit is assembled into the housing 10. Thus, the rear sub-assembly 1 has been assembled. The method of the invention comprises the following steps: providing a cap assembly 2 extending along a longitudinal axis L between a proximal end and a distal end; connecting the cap assembly 2 to the plunger rod 11 or the holder 13; and moving the cap assembly 2 relative to the housing 10 in a distal direction of the housing 10 until the cap assembly 2 is attached to the proximal end of the housing 10. During the step of moving the cap assembly 2 relative to the housing 10, the cap assembly 2 moves the plunger rod 11 relative to the holder 13.

In one example, the step of moving the plunger rod relative to the holder comprises the step of actively moving the holder 13 relative to the plunger rod 11. In this example, as shown in fig. 3C, the holder 13 includes a guide structure 132 arranged on a wall of the holder 13. The transport member shield 14 includes a guide follower 141, the guide follower 141 being configured to move along the guide structure 132 of the holder 13. The guide follower 141 may be a protrusion extending from a surface of the delivery member shroud 14 in a direction transverse to the longitudinal axis; preferably from the distal surface of the delivery member shield 14. In this example, the conveying member shield 14 is movable only in the axial direction relative to the housing. As the guide follower 141 moves along the guide structure 132 of the holder 13, the axial movement of the guide follower 141 is configured to rotate the holder 13 relative to the plunger rod 11 (if the holder 13 is a rotating member); or to move the holder 13 linearly relative to the plunger rod 11 in a direction transverse to the longitudinal axis L (if the holder is a slider). The guide structure 132 may be a labyrinth formed by a plurality of ledges (or alternatively recesses or cutouts) on the wall of the holder 13. In the example in which the holder 13 is a rotating member, the labyrinth comprises two portions 132b, 132d extending helically on the tubular body of the rotating member; thus, as the guide follower 141 of the delivery member shield 14 moves along the portions 132b, 132d, the rotator will rotate relative to the plunger rod 11. On the other hand, in the example where the retainer is a slider, the labyrinth includes diagonal portions; thus, when the guide follower of the delivery member shield is moved along the diagonal portion, the slide will move linearly with respect to the plunger rod 11 in a direction transverse to the longitudinal axis L. It should be noted that diagonal or spiral extensions 132b, 132d may also be formed at the edges of the slider or the rotator, respectively.

In one example, as shown in fig. 4B, the guide follower 141 is positioned on the pre-assembled portion 132a of the guide structure 132 prior to attaching the headgear assembly 2 to the proximal end of the shell 10. In the preferred example, the delivery member shield biasing member 15 has been assembled between the housing 10 and the delivery member shield 14. In this example, the delivery member shield 14 protrudes from the proximal end of the housing 10.

The next step is to bring the delivery member shield 14 into contact with the cap assembly 2. In a preferred example, the distal end of the cover 20 of the cap assembly 2 is aligned with the proximal end of the housing 10, and the distal end of the cover 20 of the cap assembly 2 contacts the proximal end of the delivery member shield 14. Thereafter, the cap assembly 2 moves the delivery member shield 14 in a distal direction relative to the housing 10. Distal movement of the delivery member shield 14 causes the guide follower 141 to move along one of the diagonal or helically extending portions 132b, 132d of the guide structure 132 such that the holder 13 is linearly rotated or moved relative to the plunger rod 11 until the fastener 16a of the housing 10 engages the counter-fastener 23c of the cap assembly 2. The plunger rod 11 is now in an initial position with respect to the holder 13. The delivery member shield 14 is then moved to the retracted position, compressing the delivery member shield biasing member 15. The guide follower 141 is thereby positioned in the intermediate position 132c of the guide structure 132 of the holder 13. Thus, when the end user wants to use the medicament delivery device, the end user will first remove the cap 20 from the medicament delivery device. Upon removal of the cap 20, the delivery member guard 14 will move in a proximal direction relative to the housing 10 under the biasing force of the delivery member guard biasing member 15. Thus, the guide follower 141 moves along the other of the diagonal portion or the helically extending portion 132b, 132d of the guide structure 132 such that the plunger rod 11 is released from the initial position and moves to the initial position. Thus, an initial operation of the medicament delivery device is performed. When the plunger rod 11 is in the starting position, the plunger rod 11 may be engaged with the holder 13 or any other suitable means for holding the plunger rod against the force of the plunger rod spring prior to a medicament delivery operation. In a preferred example, the retainer 13 includes a second distally-directed opposing retaining surface 13b, as shown in fig. 4D. The second distally directed counter holding surface 13b extends from one end of the distally directed counter holding surface 13a in the circumferential direction of the longitudinal axis L and is angled with respect to the distally directed counter holding surface 13a, e.g. between 10 and 80 degrees. In this example, the guide follower 141 is configured to block rotational or linear lateral movement of the retainer 13 (depending on whether the retainer 13 is a rotating or sliding member) when the guide follower 141 is positioned in the intermediate position 132c of the guide structure 132. For example, the guide structure 132 may include one or more rails that abut the guide follower 141 in a direction transverse to the longitudinal axis L. In this example, when the plunger rod 11 is in the initial position, the proximally directed retaining surface 11a engages with the distally directed counter retaining surface 13 a. During the assembly step of moving the holder 13 relative to the plunger rod 11, the plunger rod 11 is moved to an initial position and the proximally directed holding surface 11a is thus engaged with the second distally directed counter holding surface 13 b. In this example, since the second distally directed opposing retaining surface 13b is a ramp surface, once the guide follower 141 is moved out of the intermediate position 132c of the guide structure 132, the retaining element 13 will move through the plunger rod 11 under the force of the plunger rod spring 12. Thus, the delivery member shield biasing member 14 need not be too strong; and depending on the choice of the angle of the second distally directed counter holding surface the holder may comprise only one diagonal portion or a spiral extension, as the holder may now be moved by the engagement between the second distally directed counter holding surface and the plunger rod. In this example, the medicament container 3 may be a cartridge or syringe; the medicament container 3 may be assembled into the housing of the rear sub-assembly from the proximal end of the housing 10 or from the distal end of the housing. In a preferred example, prior to attaching the cap assembly 2 to the proximal end of the housing 10, the method further comprises the steps of: providing a medicament container 3; and inserting the medicament container 3 into the housing 10 from the proximal end thereof. The step of attaching the cap assembly 2 is thus the final step of assembling the medicament delivery device, which means that the medicament delivery device is ready for use by the end user from a functional point of view (the medicament delivery device may also need to be labeled and/or packaged into a package from a regulatory/sales point of view).

In another example, the step of moving the plunger rod 11 relative to the holder 13 includes the step of actively moving the plunger rod 11 relative to the holder 13. This example will be applicable to assembling a medicament delivery device comprising a cartridge; and in an assembly step, prior to attaching the cap assembly 2 to the proximal end of the housing 10, the method further comprises the steps of: providing a medicament container 3; and inserting the medicament container 3 into the housing from the proximal end of the housing 10, as shown in fig. 5A. In this example, when the rear sub-assembly 1 is provided, the plunger rod 11 is in the initial position, which means that the proximally directed holding surface 11a is engaged with the distally directed counter holding surface 13a of the holder 1, as shown in fig. 5B. During assembly, the distal end of the cover 20 of the cap assembly 2 is aligned with the proximal end of the housing 10. The step of moving the plunger rod 11 relative to the holder 13 comprises the step of bringing the proximal end of the medicament container 3 into contact with the distal portion 23b of the base 23, as shown in fig. 6A, in the preferred example, such that the proximal shoulder is in contact with the distal portion 23b of the base 23. Thus, the step of attaching the cap assembly 2 to the proximal end of the housing may also push the plunger rod 11 in a distal direction with respect to the holder 13 against the force of the plunger rod spring 12. The step further comprises moving the medicament container 3 together with the cap assembly 2 in a distal direction relative to the housing 10; bringing the proximal end of the plunger rod 11 into contact with the distal end of the medicament container 3, as shown in fig. 6B; moving the plunger rod 11 with the distal end of the medicament container 3 in a distal direction with respect to the housing 10; and moving the proximally directed surface 11a of the plunger rod 11 away from the distally directed counter holding surface 13a of the holder 13 in the direction of the longitudinal axis L, as shown in fig. 6C. The cartridge is a sealed medicament container, and therefore, the contained medicament cannot be expelled from the medicament container until fluid communication is established between the medicament container and the delivery member. Thus, when the cap assembly 2 has been attached to the proximal end of the housing 10, the distal portion 23b of the base 23 pushes the medicament container to move the plunger rod 11 in a distal direction relative to the holder 13 to the initial position of the plunger rod 11; thereafter, the plunger rod 11 is prevented from moving back to the initial/starting position by the medicament container. When the end user establishes fluid communication between the medicament container and the delivery member 21 by removing the cap 20 or attaching the delivery member (e.g. a pen needle), the medicament container is no longer sealed and it is no longer able to block the plunger rod 11 against the force of the plunger rod spring 12, so that the plunger rod 11 moves in proximal direction with respect to the holder 13 until the proximally directed surface 11a of the plunger rod 11 engages with the distally directed counter-holding surface 13a of the holder 13. And thus performs an initial operation of the medicament delivery device. In this example, the transport member shield 14 is moved to the retracted position by the cap assembly 2 or simply surrounded by the cover of the cap assembly 2.

The inventive concept was described above mainly with reference to a few examples. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended claims.

Claims (14)

1. A method of assembling a medicament delivery device, the method comprising:

-providing a housing (10) of the medicament delivery device; wherein the housing (10) extends along a longitudinal axis (L) between a proximal end and a distal end; wherein during use of the medicament delivery device, the distal end of the housing (10) is directed away from the medicament delivery site; and wherein during use of the medicament delivery device, a proximal end of the housing (10) is directed towards the medicament delivery site;

Providing a power unit of the medicament delivery device; wherein the power unit comprises a plunger rod (11) and a holder (13) in engagement with the plunger rod;

-assembling the power unit into the housing (10);

Providing a cap assembly (2) extending along the longitudinal axis (L) between a proximal end and a distal end; wherein the cap assembly (2) comprises a cover (20), the cover (20) being configured to cover a medicament delivery member of the medicament delivery device;

-connecting the cap assembly (2) to the plunger rod (11) or the holder (13); and

Moving the cap assembly (2) relative to the housing (10) in the distal direction of the housing (10) until the cap assembly (2) is attached to the proximal end of the housing (10),

Wherein during the step of moving the cap assembly (2) relative to the housing (10), the cap assembly (2) moves

(I) When the cap assembly (2) is connected to the plunger rod (11), the plunger rod (11)

Is movable relative to the housing (10); or (b)

(Ii) When the cap assembly is connected to the holder (13), the holder (13) moves relative to the housing (10).

2. The method according to claim 1, wherein prior to connecting the cap assembly (2) to the plunger rod (11) or the holder (13), the method further comprises the steps of:

providing a medicament container; and

The medicament container is inserted into the housing from a proximal end of the housing.

3. The method according to claim 1 or 2, wherein prior to assembling the power unit into the housing (10), the method further comprises the steps of:

providing a conveying member shield (14); and

-Assembling both the conveying member shield (14) and the power unit into the housing (10).

4. A method according to claim 3, wherein the method further comprises the steps of:

the delivery member shield (14) is engaged to the holder either before or after assembly of the delivery member shield and the power unit into the housing (10).

5. A method according to any of the preceding claims, wherein the step of moving the plunger rod relative to the housing comprises moving the plunger rod relative to the holder while the holder is not movable relative to the housing.

6. The method of any of claims 1-4, wherein the plunger rod is not movable relative to the housing during the step of moving the holder relative to the housing.

7. The method according to claim 5 when dependent on claim 2, or the method according to claim 3 or 4 when dependent on claim 2, wherein the step of connecting the cap assembly (2) to the plunger rod (11) comprises the steps of:

The proximal end of the medicament container is brought into contact with the cap assembly from the distal end of the cap assembly.

8. A method according to claim 7, wherein the step of moving the plunger rod (11) relative to the holder (13) comprises the steps of:

moving the medicament container in a distal direction relative to the housing using the cap assembly;

Bringing the proximal end of the plunger rod into contact with the distal end of the medicament container;

moving the plunger rod in a distal direction relative to the housing using the distal end of the medicament container;

disengaging the plunger rod from the holder by moving the plunger in a distal direction relative to the housing; and

-Attaching the cap assembly (2) to the proximal end of the housing (10).

9. A method according to claim 6 when dependent on claim 4, wherein the step of connecting the cap assembly (2) to the holder comprises the step of moving the cap assembly in a proximal direction relative to the delivery member shield such that the cap assembly contacts the proximal end of the delivery member shield.

10. A method according to claim 9, wherein the step of moving the plunger rod (11) relative to the holder (13) comprises the steps of: moving the delivery member shield in a distal direction relative to the housing using the cap assembly; moving the holder relative to the plunger rod with distal movement of the delivery member shield; and attaching the cap assembly (2) to the proximal end of the outer shell (10).

11. The method of claim 10, wherein the step of moving the holder relative to the plunger rod comprises the step of rotating the holder relative to the plunger rod with distal movement of the delivery member shield.

12. The method of claim 10, wherein the step of moving the holder relative to the plunger rod comprises the step of linearly moving the holder relative to the plunger rod in a direction transverse to the longitudinal axis with distal movement of the delivery member shield.

13. The method of any of the preceding claims, wherein when the cap assembly is attached to the proximal end of the housing, the cap assembly is moved axially relative to the housing toward the distal end of the housing until the cap assembly is snap-fit to the housing.

14. The method of any of claims 2-13, wherein the medicament delivery device is functionally complete after attaching the cap assembly to the proximal end of the housing.