the container 10 as schematically shown in fig1 comprises an inner volume 11 or an interior confined by a wall structure 12 . in this embodiment the wall structure 12 is formed by an upper sidewall 13 and a lower sidewall 14 . both sidewalls 13 , 14 may comprise a flexible material , such like an elastic foil . the two sidewalls 13 , 14 may comprise a somewhat identical shape and circumference so that they are arrangeable on top of each other such that their side edges may be interconnected to form a seam 15 . the overall geometric shape of the sidewalls 13 , 14 is somewhat arbitrary . the two sidewalls 13 , 14 mutually interconnected , e . g . mutually welded or adhesively connected along the surrounding seam 15 to form the inner volume 11 that may be completely filled with a liquid medicament 18 . it is generally conceivable that one of the sidewalls 13 , 14 is rather rigid and inflexible while the other one of the sidewalls 14 , 13 is flexible . the two sidewalls 13 , 14 may form a flexible bag or pouch that is filled with the liquid medicament 18 . hence , at least one of the sidewall portions 13 , 14 forms a flexible portion 13 , 14 of the container &# 39 ; s wall structure 12 . there is further provided an extraction tube 20 extending into the inner volume 11 . as indicated in fig1 , the extraction tube 20 comprises a first portion 21 forming a free end thereof that is freed from an inside - facing portion 12 a of the wall structure 12 . typically , the extraction tube 20 is flexible . it further comprises a first portion 22 forming a free end or distal end 21 thereof that is freed and moveable inside the inner volume 11 thanks to the flexibility of the extraction tube 20 . the extraction tube 20 further comprises a second portion 24 that is located at a predefined longitudinal or axial distance from the first portion . hence , the second portion 24 is located proximally offset from the distal end 21 of the extraction tube 20 . as can be seen in fig1 , the extraction tube 20 further comprises a proximal portion 27 opposite to the first portion 22 or opposite to the distal end 21 . the proximal portion 27 is located inside or attached to a rigid interface member 30 that provides a well - defined coupling or connection to a piercing assembly 40 . the proximal portion 27 is rigidly attached to the interface member 30 . the interface member 30 is also attached to the wall structure and may extend through the wall structure so that the interface member 30 is accessible from outside . eventually , the extraction tube 20 is fixed with its second portion 24 to the inside - facing portion 12 a of the wall structure 12 . in this way , only a very distal end 21 of the extraction tube 20 is free to move inside the inner volume 11 . alternatively , it is conceivable that the entire section of the extraction tube 20 extending into the inner volume 11 of the wall structure 12 is free from the wall structure 12 or is completely fixed to an inside - facing portion 12 a of the wall structure 12 . both embodiments may be beneficial for a complete emptying of the inner volume 11 depending on the geometry of the wall structure 12 and the flexible material or material combinations the wall structure 12 is made of . as can be further seen from fig1 , the proximal portion 27 of the extraction tube 20 is blocked by a pierceable seal 32 . the seal 32 and the proximal portion 27 are fixedly or rigidly attached to the interface member 30 . they may be even located inside the interface member 30 . as can be further seen from a combination of fig1 and 2 there is also provided a piercing assembly 40 having a fastening member 43 to engage with a guiding structure 33 of the interface member 30 . furthermore , the piercing assembly 40 comprises a piercing element 44 extending horizontal in the illustration according to fig1 . in particular , the piercing element 44 , typically implemented as a hollow and tipped cannula extends parallel to the extension of the proximal portion 27 of the extraction tube 20 in which the pierceable seal 32 is located . by aligning the piercing assembly &# 39 ; s 40 fastening member 43 to the guiding structure 33 of the interface member 30 the piercing element 44 of the piercing assembly 40 is co - aligned with the seal 32 . the elongation of the guiding structure 33 to engage with claw - like - shaped fastening members 43 of the piercing assembly requires that a mutual fixing of piercing assembly 40 and interface member 30 is obtained through a translational displacement of the piercing assembly 40 relative to the interface member 30 in a direction parallel to the elongation of the proximal portion 27 . this translational displacement is sufficient for the piercing element 44 to enter the proximal portion 27 of the extraction tube 20 and to pierce and to intersect the pierceable seal 32 . the guiding structure 33 , presently illustrated as a recessed groove on oppositely located sidewall portions of the interface member 30 engages with inwardly - facing prongs 45 of the claw - shaped fastening members 43 of the piercing assembly 40 . in this way , a clip - like mutual fastening of the piercing assembly 40 and the interface member 30 can be obtained when the piercing assembly 40 has been translationally shifted relative to the interface member 30 as defined by the shape of the guiding structure 33 and its sliding interaction with the prongs 45 of the claw - shaped fastening members 43 of the piercing assembly 40 . even though not illustrated in fig1 the end of the tipped piercing element 44 not penetrating the seal 32 or septum of the tube 20 is typically connected with some kind of further tubing in order to feed and to transport the liquid medicament to an injection site . by means of the guiding structure 33 a well - defined and collisionless guiding of the distal tip of the piercing element 44 into and through the proximal portion 27 of the extraction tube 20 can be provided . thanks to the guiding structure 33 , a danger of inadvertently damaging the tipped end of the piercing element 44 can be effectively minimized . in fig3 the shape and configuration of a first embodiment of the extraction tube 20 , in particular of its first portion 22 is schematically illustrated . the first portion 22 forms the distal end 21 of the extraction tube which is open at its distal front face . in addition the first portion 22 comprises numerous drain holes 25 regularly arranged across the sidewall 23 of the extraction tube . the drain holes 25 homogeneously extend over and across the outer circumference of the sidewall 23 of the extraction tube 20 and even extend into a second portion 24 of the extraction tube 20 . in the embodiment according to fig3 the first portion 22 of the extraction tube 20 exhibits and comprises a lower resistivity against radial collapsing than the second portion 24 . this is e . g . obtainable by reducing the thickness of the sidewall 23 towards the distal end 21 , hence from the second portion 24 towards the first portion 22 . in another embodiment as shown in fig4 , the extraction tube 120 comprises a distal end 121 formed by a first portion 122 . longitudinally adjacent to the first portion 122 there is provided a second portion 124 . as can be seen from the schematic illustration of fig4 , the cross - section 125 of the first portion 122 is somewhat oval , while the cross - section of the second portion 124 is substantially circular . here , a density or geometry of the individual drain holes 25 may be homogeneous across first and second portions 122 , 124 . simply by changing the geometry and the cross - section of the first portion 122 , the first portion 122 exhibits and comprises a lower resistivity against radial collapsing than the second portion 124 . in effect and upon complete emptying of the container 10 , the collapsing wall structure 12 starts to exert a compressive force to the extraction tube 20 . thanks to the oval cross - section 125 in the first portion 122 the first portion starts to collapse , thereby expelling a liquid substance located therein in proximal direction and further towards the second portion 124 . as the compressive force or pressure acting on the extraction tube 20 raises further , also the second portion 124 will start to collapse , typically starting from distal direction towards the proximal direction . in another embodiment as shown in fig5 the extraction tube 220 also comprises a distal end 221 formed by a first portion 222 . as can be seen in the illustration according to fig5 , the overall outer cross - section of the first portion 222 is somewhat circular . here , the inner cross - section 225 is oval - shaped . this is obtained due to variations in the thickness of the sidewall 223 of the first portion 222 compared to the second portion 224 . as shown in fig5 , the thickness profile along the circumference of the sidewall 223 is somewhat oval . a left and right sidewall portion as shown in fig5 have a somewhat reduced thickness whereas upper and lower portions of the sidewall 223 are substantially thickened compared to the sidewall thickness as indicated by dotted lines in the second portion 224 . an inhomogeneous thickness or varying thickness of the sidewall 223 along the circumference of the cross - section of the first portion 222 leads to a structural weakening and to a reduced resistivity against collapsing in response to an application of a compressive force . in the embodiment according to fig6 the extraction tube 320 also comprises an open distal end 321 formed by a first part 322 . also here , the first part 322 is offset in longitudinal direction from a second part 324 . but in contrast to the embodiments as shown in fig3 and 5 the density of drain holes 25 is larger in the first portion 322 compared to the second portion 324 . the increase in density of drain holes 25 also leads to a structural weakening of the first portion 322 , which therefore also exhibits a reduced resistivity against radial collapsing compared to the second portion 324 . in the embodiment according to fig7 at least two different types of drain holes 25 , 26 are used . also here , the extraction tube 420 comprises a distal end 421 formed by a first portion 422 . in the region of the first portion 422 drain holes 26 are located that are larger than drain holes 25 provided in a second portion 424 longitudinally adjacent or longitudinally offset from the first portion 422 . here , the drain holes 25 , 26 may have an equal or similar density per surface segment of the extraction tube 420 , but the drain holes 26 provided at the first portion 422 are larger than the drain holes 25 provided at the second portion 424 . in this way , the distal end 421 is structurally weakened compared to the second portion 424 . in fig8 there is schematically illustrated an injection device 50 comprising a compartment 52 to receive and to accommodate a container 10 as described above . as schematically shown in fig8 , the injection device 50 comprises a pump 54 connected to a piercing assembly 40 via a tubing 56 . the pump 54 is typically implemented as a suction pump to withdraw the liquid medicament from the interior 11 of the container 10 when connected to the tubing 56 . a distal end of the tubing 56 is located inside or is connected to a piercing assembly 40 that is arranged inside the compartment 52 to connect with the container 10 via its interface member 30 . once a fluid transferring interconnection of container 10 and piercing assembly 40 is established , the liquid medicament 18 can be withdrawn from the container 10 via the tubing 56 . by means of the pump 54 , the liquid medicament is transferrable towards a device outlet 58 and further to a patient .
the present disclosure relates to a container for a liquid medicament that includes a wall structure with at least one flexible portion and confining an inner volume filled with the liquid medicament and an elongated extraction tube having at least a first portion and a second portion that are separated from each other along the tube and which are located inside the inner volume . the extraction tube is radially collapsible when exposed to a compressive force above a predefined threshold , and the first portion , which is located at a distal end of the extraction tube , is less resistive against radial collapsing than the second portion .