Transport assembly for a medicament delivery device and a medicament delivery device comprising the same

A transport assembly for shipping components of a medicament delivery device to final assembly is presented, where the transport assembly has a plunger rod, a first resilient member configured to bias the plunger rod, an elongated plunger rod holder configured to receive the plunger rod, a transport securing sleeve configured to receive a portion of the plunger rod holder, and configured to move axially from a first position relative to the plunger rod holder in which the transport securing sleeve prevents the plunger rod holder to disengage from the plunger rod to a second position located distally relative to the first position, enabling disengagement of the plunger rod holder from the plunger rod, a rear end cap, and a second resilient member configured to bear against the rear end cap and configured to bias the transport securing sleeve in the proximal direction away from the second position.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a U.S. National Phase Application pursuant to 35 U.S.C. § 371 of International Application No. PCT/EP2018/067777 filed Jul. 2, 2018, which claims priority to European Patent Application No. 17180916.3 filed Jul. 12, 2017. The entire disclosure contents of these applications are herewith incorporated by reference into the present application.

TECHNICAL FIELD

The present disclosure generally relates to medical devices. In particular, it relates to a transport assembly for a medicament delivery device, to a medicament delivery device comprising a transport assembly and to a method of shipping components of a medicament delivery device for final assembly.

BACKGROUND

Medicament delivery devices, in particular automated administration devices such as auto-injectors, are typically spring-biased. A device of this type may be activated for example by pushing the device towards the injection site, whereby a delivery member cover is moved in the proximal direction further into the housing, causing the device activation, or by means of an external button or slider.

Medicament delivery devices of the above type may often be shipped as sub-assemblies to the site of final assembly. This is because the components of the medicament delivery device may be manufactured at a different location than the location of final assembly, where a medicament container containing the medicament is placed inside the housing of the medicament delivery device.

One of the sub-assemblies may comprise an administration assembly, or “power-pack”, which for an automated injection device typically comprises a spring-biased component such as a plunger rod. The biasing force in the power-pack may be substantial to provide the required force to push the medicament out through the delivery member.

There is a risk that the power-pack fires off due to vibrations or impact during shipping. This may result in additional work to reload fired-off power-packs once the location of final assembly has been reached, or if reloading is not possible fired-off sub-assemblies may have to be discarded. There is additionally a risk that personnel may be injured if a power-pack is being fired off during handling of the sub-assemblies. One way to reduce the risk of personal injuries is to pack each sub-assembly in its own package for shipment, but this leaves a substantial spatial and environmental footprint and thus makes transport less efficient and more expensive.

SUMMARY

In view of the above, a general object of the present disclosure is to provide a transport assembly for a medicament delivery device which solves or at least mitigates problems of the prior art.

There is hence according to a first aspect of the present disclosure provided a transport assembly for shipping components of a medicament delivery device to final assembly, the transport assembly being configured to be mounted into a housing of a medicament delivery device, comprising: a plunger rod, a first resilient member configured to bias the plunger rod in the proximal direction, an elongated plunger rod holder configured to receive the plunger rod and configured to engage with the plunger rod to prevent the plunger rod from movement in the proximal direction, a transport securing sleeve configured to receive a portion of the plunger rod holder, and configured to move axially from a first position relative to the plunger rod holder in which the transport securing sleeve prevents the plunger rod holder to disengage from the plunger rod to a second position located distally relative to the first position, enabling disengagement of the plunger rod holder from the plunger rod, a rear end cap, and a second resilient member configured to bear against the rear end cap and configured to bias the transport securing sleeve in the proximal direction away from the second position.

Due to the proximally directed biasing of the transport securing sleeve, the transport securing sleeve is biased away from the second position preventing the plunger rod holder from disengaging from the plunger rod. Thus, as long as the transport securing sleeve is in such an axial position that it prevents disengagement, the plunger rod will not be fired off. The second resilient member hence protects from accidental firing of the plunger rod, which could otherwise have been triggered by vibrations or impact during transport of the transport assembly. There is hence a reduced risk of accidental triggering of the plunger rod during shipping.

According to one embodiment the rear end cap has a tubular body and the transport securing sleeve is configured to receive a portion of the tubular body, the transport securing sleeve being configured to be set in a transport position located proximally from the first position, the transport securing sleeve being configured to prevent the plunger rod holder from disengaging from the plunger rod in the transport position, and wherein in the transport position the transport securing sleeve is configured to engage with the tubular body to retain the transport securing sleeve in the transport position.

The transport securing sleeve is releasably engageable with the tubular body of the rear end cap. Under normal conditions, the transport securing sleeve will remain engaged with the tubular body when placed in the transport position. However, if sufficient force in the distal direction is applied to the transport securing sleeve, the transport securing sleeve will disengage from the tubular body. This is normally done when the transport assembly has reached the location of final assembly. The transport securing sleeve is here disengaged from the tubular body by moving it in the distal direction, whereby it attains its first position.

According to one embodiment the tubular body is provided with a radially outwards extending protrusion and the transport securing sleeve has a recess configured to receive the radially outwards extending protrusion in the transport position to retain the transport securing sleeve in the transport position.

According to one embodiment the radially outwards extending protrusion has a distal end face configured to prevent the transport securing sleeve to return to the transport position once the transport securing sleeve has been moved from the transport position to the first position.

The tubular body may hence be provided with a radially outwards extending protrusion, or transport securing sleeve lock, which prevents the transport securing sleeve from moving from the first position further in the proximal direction once it has been set in the first position.

According to one embodiment the second resilient member is a spring.

According to one embodiment the spring is a compression coil spring.

According to one embodiment the transport securing sleeve has a proximal portion having a first outer diameter and a distal portion located distally with respect to the proximal portion having a second outer diameter which is smaller than the first diameter, wherein a distal flange surface defines the transition from the distal portion to the proximal portion, and wherein the second resilient member is configured to bear against the distal flange surface to thereby bias the transport securing sleeve towards the first position.

According to one embodiment the rear end cap has an end flange surface and a tubular body extending proximally from the end flange surface, wherein the tubular body is configured to receive the plunger rod holder.

According to one embodiment the tubular body is configured to engage with the plunger rod holder to prevent relative axial movement between the plunger rod holder and the rear end cap.

According to one embodiment the plunger rod holder has a first hold and release structure and the plunger rod has a second hold and release structure, wherein in the first position the transport securing sleeve is configured to maintain the first hold and release structure in an axially locking contact position with the second hold and release structure in which the second hold and release structure is prevented from movement relative to the first hold and release structure, thereby locking the plunger rod axially relative to the plunger rod holder, wherein in the second position the transport securing sleeve is configured to allow the first hold and release structure to move from the axially locking contact position, whereby biasing of the plunger rod provided by the first resilient member causes the second hold and release structure to act with a proximally directed force on the first hold and release structure, moving the first hold and release structure from the axially locking contact position to thereby release the plunger rod from the plunger rod holder.

There is according to a second aspect of the present disclosure provided a medicament delivery device comprising: a housing, and a transport assembly as according to the first aspect, configured to be received by the housing.

There is according to a third aspect of the present disclosure provided a method of shipping components of a medicament delivery device for final assembly, wherein the method comprises: placing a plurality of transport assemblies according to the first aspect in a box.

According to one embodiment the transport assemblies are placed in direct contact with each other in the box.

One embodiment comprises prior to placing the plurality of transport assemblies in the box, setting each transport assembly in a transport mode by setting each transport securing sleeve in a transport position to engage with a respective rear end cap.

DETAILED DESCRIPTION

In the present disclosure, when the term “distal direction” is used, this refers to the direction pointing away from the dose delivery site during use of the medicament delivery device. When the term “distal part/end” is used, this refers to the part/end of the delivery device, or the parts/ends of the members thereof, which under use of the medicament delivery device is/are located furthest away from the dose delivery site. Correspondingly, when the term “proximal direction” is used, this refers to the direction pointing towards the dose delivery site during use of the medicament delivery device. When the term “proximal part/end” is used, this refers to the part/end of the delivery device, or the parts/ends of the members thereof, which under use of the medicament delivery device is/are located closest to the dose delivery site.

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

Similarly, the terms “transverse”, “transversal” and “transversally” refer to a direction generally perpendicular to the longitudinal direction.

FIG. 1shows an example of a transport assembly1for a medicament delivery device. The transport assembly1is adapted to be shipped from the location of assembly to the location of final assembly of the medicament delivery device. Hereto, the transport assembly1is specifically adapted for reducing the risk of accidental firing off of a biased component contained therein, as will be described in more detail in what follows.

The transport assembly1comprises an essentially cylindrical transport securing sleeve3and a rear end cap5having a tubular body5aconfigured to be received by the transport securing sleeve3. The transport securing sleeve3is configured to be moved axially relative to the tubular body5a. The transport assembly1further comprises an elongated plunger rod holder7configured to be received by the tubular body5a, a plunger rod9configured to be received by the plunger rod holder7, and a resilient member8, in the following referred to as second resilient member8, configured to bias the transport securing sleeve3in the proximal direction.

The transport assembly1is configured to be set in a transport mode depicted inFIG. 1, and in a medicament administration mode shown inFIG. 8. In the transport mode, the transport securing sleeve3is set in a transport position. In the transport position, the transport securing sleeve3engages with the tubular body5aof the rear end cap5. To set the transport assembly1in the medicament administration mode, the transport securing sleeve3is disengaged from the tubular body5aby acting on it with a sufficiently high force in the distal direction. The transport securing sleeve3is thus set in a first position relative to the rear end cap5. In the medicament administration mode the transport securing sleeve3is configured to be moved between the first position and a second position. The second position is located distally with respect to the first position. The second resilient member8is configured to bias the transport securing sleeve3in the proximal direction, away from the second position both in the transport mode and in the medicament administration mode. In the medicament administration mode, the second resilient member8is configured to bias the transport securing sleeve3towards the first position.

FIG. 2is an exploded view of the transport assembly1. The transport assembly further comprises a first resilient member11, for example a spring, a rod13, and a second resilient member15, for example a spring.

The plunger rod holder7is configured to receive the plunger rod9. The plunger rod has9has an inner axial channel, not shown. The first resilient member11is configured to be received by the plunger rod9. In particular, the first resilient member11is configured to be received in the axial channel of the plunger rod9. The first resilient member11is configured to receive the rod13when arranged in the axial channel. Bending of the highly stiff first resilient member11can thus be prevented.

The plunger rod holder7is configured to engage with the plunger rod9, to prevent movement of the plunger rod9in the proximal direction when the transport securing sleeve3is in the first position or in the transport position. The transport securing sleeve3encloses the plunger rod holder7and the plunger rod9circumferentially, and depending on the particular realisation of the transport securing sleeve3, restricts tangential or radial movement of the plunger rod holder7in the first position and in the transport position. In the present example, the transport securing sleeve3is configured to restrict tangential movement of the plunger rod holder7when in the first position and in the transport position, as will be explained in more detail in what follows.

FIG. 3shows the transport securing sleeve3removed from the tubular body5aof the rear end cap5. The transport securing sleeve3has a distal portion3aand proximal portion3b. The distal portion3ahas a smaller outer diameter than the proximal portion3b. The transport securing sleeve3has a distal flange surface3cwhich defines the transition between the distal portion3aand the proximal portion3b. The transport securing sleeve3also has a proximal flange surface3dwhich defines a proximal face of the transport securing sleeve3.

The rear end cap5has an end flange surface5b. The second resilient member8is configured bear against the end flange surface5bof the rear end cap5and against the distal flange surface3cof the transport securing sleeve3. The transport securing sleeve3is thus biased in the proximal direction by the second resilient member8.

The transport securing sleeve3is furthermore configured to engage with the tubular body5aof the rear end cap5when the transport securing sleeve3is in the transport position. Hereto, the transport securing sleeve3has a recess or opening3eand the tubular body5ahas a radially outwards extending protrusion5cconfigured to be received by the recess3e. When the transport securing sleeve3is moved to the transport position, the radially outwards extending protrusion5cengages with the recess3e. The radially outwards extending protrusion5cmay be wedge-shaped or bevelled to allow for the transport securing sleeve3to disengage from the tubular body5aif sufficient force is applied in the distal direction. Moreover, the radially outwards extending protrusion5chas a distal end face5dconfigured to prevent the transport securing sleeve3to return to the transport position once the transport securing sleeve3has been moved from the transport position to the first position.

Turning now toFIG. 4a perspective view of the plunger rod holder7, the plunger rod9and the transport securing sleeve3are shown. The plunger rod9is received by the plunger rod holder7. The exemplified plunger rod holder7has a first hold and release structure7a, which comprises a first arm10aand a second arm10bextending parallel with each other. The first arm10aand the second arm10bextend in the distal direction from their attachment with a main body10cof the plunger rod holder7. Each of the first arm10aand the second arm10bhas a tangential extension which is typically less than 90 degrees. To this end, the circumferential or tangential extension of each of the first arm10aand the second arm10bis typically less than one fourth of a turn in the circumferential direction of the plunger rod holder7. The plunger rod holder7may for instance be provided with four arms in total, which is the case in the present example. Each arm, e.g. the first arm10aand the second arm10b, may be connected to the main body10cof the plunger rod holder7by means of living hinges. Each of the first arm10a, the second arm10b, and the two remaining arms, may due to their slender nature be flexible in the tangential direction.

Although there may be in total four arms provided, only the first and the second arm10a,10b, which form a first arm pair, will be described in more detail in the following. The third and the fourth arm form a second arm pair. The structure of all the arms is the same.

The first arm10acomprises a first tangential tab10dand the second arm10bcomprises a second tangential tab10e. The first and second tangential tabs10dand10eextend towards each other in the tangential direction. The tangential distance between the first arm10aand the second arm10bhence decreases between the two tangential tabs10dand10e.

The plunger rod9comprises a second hold and release structure9a, which in the present example comprises a radially outward extending protrusion or wing. The first and second tangential tabs10dand10eare configured to cooperate with the radially outwards extending protrusion. In particular, two tangential tabs10dand10eare configured to block proximal movement of the radially outwards extending protrusion and thus of the plunger rod9when the transport securing sleeve3is in the first position or in the transport position. The distance between the two tangential tabs10dand10eis too small for the radially outwards extending protrusion to pass between. The plunger rod9is hence maintained in an axially locked position with the plunger rod holder7when the transport securing sleeve3is in the first position or in the transport position.

The transport securing sleeve3is tubular and has an inner surface provided with axially extending ribs3fAxially extending ribs3balso are provided inside the distal portion3aof the transport securing sleeve3, as shown inFIG. 5. The axially extending ribs3fand3hare configured to run between the first arm pair and the second arm pair. In particular, the first arm10aand the second arm10bare prevented from tangential movement as long as the axially extending ribs3hinside the distal portion3aof the transport securing sleeve3run between the first arm pair and the second arm pair. Once these axially extending ribs3hmove distally beyond the first arm10aand the second arm10band out from their position between the first arm pair and the second arm pair, when the transport securing sleeve3has been moved sufficiently in the distal direction from the first position towards the second position, the biasing of the plunger rod9and the contact between the radially outwards extending portion and the two tangential tabs10dand10e, will force the first arm10aand the second arm10bto move in the tangential direction. The inner diameter of the distal portion3acannot accommodate any substantial radial movement of the first arm10aand the second arm10b. The distance between the opposing first tangential tab10dand the second tangential tab10ewill thus increase, allowing the radially outwards extending portion to pass between. The plunger rod9is thus released from engagement with the plunger rod holder7.

The transport securing sleeve3also has outer axial ribs3gconfigured to run in corresponding slots in the tubular body5of the rear end cap5. The transport securing sleeve3is thereby prevented from rotation relative to the rear end cap5. Since the transport securing sleeve3has the axially extending ribs3fand3hrunning between the first arm pair and the second arm pair of the plunger rod holder7, the plunger rod holder7is also prevented to rotate relative to the rear end cap5. Additionally, the plunger rod9is rotationally locked relative to the plunger rod holder7since the radially outwards extending protrusion is configured to run in the space between the first arm10aand the second arm10b. The radially outwards extending protrusion hence forms a guiding structure to prevent rotation of the plunger rod9relative to the plunger rod holder7. All of the above-described components are hence prevented to rotate relative to the housing of the medicament delivery device in which they are mounted.

FIG. 6shows three sub-assemblies of a medicament delivery device18, in the present example an auto-injector. A first of these sub-assemblies is the transport assembly1described above. The transport assembly1is here set in the transport mode with the transport securing sleeve3in the transport position engaging with the tubular body5aof the rear end cap5.

A second sub-assembly17includes a housing19having a proximal end19aand a distal end19b, a delivery member cover21extending from a proximal opening in the proximal end19aof the housing19, and a medicament container holder, not shown.

In a fully assembled state of the medicament delivery device18, the delivery member cover21is biased in the proximal direction. The delivery member cover21is configured to be moved linearly, or axially, relative to the housing19. The delivery member cover21is configured to be moved between an extended position relative to the housing19, shown inFIG. 6, and a retracted position relative to the housing19. In the retracted position, a greater portion of the delivery member cover21is received by the housing19than in the extended position. The delivery member cover21is configured to be biased towards the extended position. In particular, the delivery member cover21has a distal end which is configured to cooperate with the proximal flange surface3dof the transport securing sleeve3. Movement of the delivery member cover21from the extended position towards the retracted position hence causes the transport securing sleeve3to move from the first position towards the second position.

The third sub-assembly depicted inFIG. 6includes a medicament container23provided with a delivery member and including a medicament, a stopper arranged in the medicament container and configured to be moved linearly inside the medicament container by the plunger rod9, and a delivery member shield25.

Typically, when performing final assembly of the medicament delivery device18, the third sub-assembly, which includes the medicament container23, is placed inside the housing19through a distal opening at the distal end19bof the housing19. The transport assembly1is set in the medicament administration mode from the transport mode by moving the transport securing sleeve3in the distal direction so that it disengages from the tubular body5aof the rear end cap5. Finally, the transport assembly1is mounted in the housing19through the distal opening at the distal end19b.

The fully assembled medicament delivery device18is shown inFIG. 7.FIG. 8shows the medicament delivery device18with the housing19removed. Here, it can be seen that the transport securing sleeve3is in the first position, which is located distally with respect to the transport position shown inFIG. 1.

FIG. 10shows a flowchart of a method of shipping components of the medicament delivery device18. First, when the components of the transport assembly1have been manufactured, they are assembled, for example by means of pick and place robots. During the assembly, in a step S0the transport securing sleeve3of each transport assembly1may be set in the transport position. The transport securing sleeve3thus engages with the tubular body5aof the rear end cover5. Next, in a step S1a plurality of transport assemblies1, each being set in the transport mode are placed inside a box. Since the risk of accidental firing of the plunger rod9is reduced by means of the forward biasing provided by the second resilient member8onto the transport securing sleeve3and due to the engagement between the transport securing sleeve3and the tubular body5a, the box can be filled with a plurality of transport assemblies1, placed in direct contact with each other. The transport assemblies1may for example be placed one after the other and/or stacked in several layers on top of each other in the box.

To illustrate an example of engagement and disengagement between the plunger rod holder7and the plunger rod9, the operation of the fully assembled medicament delivery device18will now be described with reference toFIGS. 10a-10c.

InFIG. 1aa longitudinal section of a distal end portion of the medicament delivery device18comprising the transport assembly1is shown. The transport securing sleeve3is in the first position and the axially extending ribs3hare provided between the first arm pair and the second arm pair, preventing e.g. the first arm10aand the second arm10bfrom moving in the tangential direction. The second hold end release structure9a, including the radially outwards extending protrusion is thus not able to move past the two distal end tangential extending portions10dand10e.

InFIG. 10bthe transport securing sleeve3has been moved in the distal direction towards the second position by the delivery member cover, which cannot be seen in this longitudinal section. The transport securing sleeve3has been moved to an activation position, which is where the axially extending ribs3hof the distal portion3amove out from between the first arm pair and the second arm pair. This allows the hinged first arm10aand the second arm10bto move tangentially, due to the force acting thereon by the biased radially outwards extending portion of the plunger rod9.

InFIG. 10cthe transport securing sleeve3is in the second position, the first arm10aand the second arm10bhave been moved in the tangential direction and the plunger rod9has thus been released from being axially locked with the plunger rod holder7. The plunger rod9has in particular been moved in the proximal direction as indicated by the arrow.