Abstract:
Describe is a needle assembly replacement device ( 1 ) comprising a chassis ( 5 ), a contact plate ( 7 ) translatably disposed on the chassis ( 5 ) and having an opening ( 8 ) adapted to receive a medicament delivery device ( 2 ), and a plurality of gripping wheels ( 10 ) rotatably coupled to the chassis ( 5 ) and adapted to releasably engage a cover ( 4 ) of a needle assembly ( 3 ). The gripping wheels ( 10 ) are adapted to rotate in a first rotational direction when the contact plate ( 7 ) translates relative to the chassis ( 5 ) in a first axial direction and rotate in a second rotational direction when the contact plate ( 7 ) translates relative to the chassis ( 5 ) in a second axial direction. Rotation of the gripping wheels ( 10 ) in the first rotational direction engages the needle assembly ( 3 ) to the medicament delivery device ( 2 ), and rotation of the gripping wheels ( 10 ) in the second rotational direction disengages the needle assembly ( 3 ) from the medicament delivery device ( 2 ).

Description:
TECHNICAL FIELD 
       [0001]    The invention relates to a needle assembly replacement device which is adapted to engage and disengage a needle assembly to/from a medicament delivery device. 
       BACKGROUND OF THE INVENTION 
       [0002]    Conventional medicament delivery devices typically require a needle assembly for creating a fluid path between a medicament container and a needle. It is generally recommended to use an unused injection needle for each injection in order to reduce the risk for cross contamination, infection and pain associated with reuse of used needles. 
         [0003]    Many users of medicament delivery devices, such as pen injectors and autoinjectors, may be elderly or have reduced dexterity. For these groups, mounting needle assemblies to the delivery device may be problematic if the needle assembly is not oriented corrected, which may disrupt the fluid path for the medicament or may lead to a painful injection process. Further, removing used injection needles can be difficult and may subject the user to the risk of needle stick injuries. Generally, it is recommended that needles be removed with care to avoid needle stick injury. 
         [0004]    Thus, there remains a need for an improved needle assembly magazine which facilitates needle assembly mounting and removal on/from a medicament delivery device. 
       SUMMARY OF THE INVENTION 
       [0005]    It is an object of the present invention to provide a needle assembly replacement device. 
         [0006]    In an exemplary embodiment, a needle assembly replacement device according to the present invention comprises a chassis, a contact plate translatably disposed on the chassis and having an opening adapted to receive a medicament delivery device, and a plurality of gripping wheels rotatably coupled to the chassis and adapted to releasably engage a cover of a needle assembly. The gripping wheels are adapted to rotate in a first rotational direction when the contact plate translates relative to the chassis in a first axial direction and rotate in a second rotational direction when the contact plate translates relative to the chassis in a second axial direction. Rotation of the gripping wheels in the first rotational direction engages the needle assembly to the medicament delivery device, and rotation of the gripping wheels in the second rotational direction disengages the needle assembly from the medicament delivery device. 
         [0007]    In an exemplary embodiment, the opening includes a contoured perimeter adapted to guide the medicament deliver device into a predetermined position relative to the contact plate. 
         [0008]    In an exemplary embodiment, the needle assembly replacement device further comprises a spring biasing the contact plate in the second axial direction relative to the chassis. 
         [0009]    In an exemplary embodiment, the needle assembly replacement device further comprises a plurality of lead screws coupled to the chassis. Each of the lead screws supports one of the gripping wheels. The gripping wheel is adapted to translate and rotate relative to the lead screw. The lead screw includes a helical channel adapted to mate with a radial projection on the gripping wheel. 
         [0010]    In an exemplary embodiment, the needle assembly replacement device further comprises a needle support arranged to slide transversely relative to the chassis. The needle support is adapted to hold a new cover of a further needle assembly. The needle support includes a first cam track adapted to receive a first follower pin coupled to a leg which translates in conjunction with the contact plate. Engagement of the first follower pin with the first cam track causes the needle support to slide transversely in a first transverse direction as the contact plate translates in the first axial direction until the new cover is aligned with the opening. 
         [0011]    In an exemplary embodiment, the needle assembly replacement device further comprises a needle wedge arranged to slide transversely relative to the chassis. The needle wedge includes a ramp adapted to slide through a through-slot formed in the needle support. The needle wedge includes a second cam track adapted to receive a second follower pin coupled to the leg. Engagement of the second follower pin with the second cam track causes the needle wedge to slide transversely in a first transverse direction as the contact plate translates in the first axial direction until the ramp axially displaces the new cover to engage the gripping wheels. 
         [0012]    In an exemplary embodiment, one or more springs bias the needle support and the needle wedge in a second transverse direction opposite the first transverse direction. 
         [0013]    In an exemplary embodiment, the second cam track includes a lowermost portion which, when the second follower pin is engaged in the lowermost portion, prevents axial movement of the contact plate in the first axial direction and provides a tactile feedback. 
         [0014]    In an exemplary embodiment, the gripping wheels include grooves which, when aligned with the cover, release the cover from the gripping wheels. 
         [0015]    The exemplary embodiments of the needle replacement device according to the present invention allow a user to remove a used needle assembly from a medicament delivery device and engage an unused needle assembly to the delivery device without direct contact with either needle assembly. Thus, the risk of needle stick injuries is remarkably reduced. 
         [0016]    Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0017]    The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein: 
           [0018]      FIG. 1  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device prior to use, 
           [0019]      FIG. 2  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device during use, 
           [0020]      FIG. 3  is a schematic detail view of an exemplary embodiment of gripping wheels for a needle assembly replacement device during use, 
           [0021]      FIG. 4  is a schematic detail view of an exemplary embodiment of a needle support and a needle wedge for a needle assembly replacement device during use, 
           [0022]      FIG. 5  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device during use, 
           [0023]      FIG. 6  is a schematic detail view of an exemplary embodiment of gripping wheels for a needle assembly replacement device during use, 
           [0024]      FIG. 7  is a schematic detail view of an exemplary embodiment of a needle support and a needle wedge for a needle assembly replacement device during use, 
           [0025]      FIG. 8  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device during use, 
           [0026]      FIG. 9  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device during use, 
           [0027]      FIG. 10  is a schematic detail view of an exemplary embodiment of gripping wheels for a needle assembly replacement device during use, 
           [0028]      FIG. 11  is a schematic detail view of an exemplary embodiment of a needle support and a needle wedge for a needle assembly replacement device during use, 
           [0029]      FIG. 12  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device during use, 
           [0030]      FIG. 13  is a schematic detail view of an exemplary embodiment of gripping wheels for a needle assembly replacement device during use, 
           [0031]      FIG. 14  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device during use, 
           [0032]      FIG. 15  is a schematic detail view of an exemplary embodiment of gripping wheels for a needle assembly replacement device during use, 
           [0033]      FIG. 16  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device during use, and 
           [0034]      FIG. 17  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device after use. 
           [0035]    Corresponding parts are marked with the same reference symbols in all figures. 
       
    
    
     DETAILED DESCRIPTION 
       [0036]      FIG. 1  is a schematic perspective view of an exemplary embodiment of a needle assembly replacement device  1  prior to insertion of a medicament delivery device  2 . The needle assembly replacement device  1  removes a used needle assembly  3  from a medicament delivery device  2  and engages a new needle assembly  3  to the medicament delivery device  2 . In an exemplary embodiment, the needle assembly  3  is attached to the medicament delivery device  2  by a threaded interface, e.g., threads on the needle assembly  3  engage with threads on the delivery device  2 . 
         [0037]    In an exemplary embodiment, the needle assembly replacement device  1  comprises a chassis  5  with an outer wall  6  and a contact plate  7  having an opening  8  intended to receive a distal end of the medicament delivery device  2  with a needle assembly  3  attached thereto. A portion of the delivery device  2  may contact the contact plate  7  such that axial force applied to the delivery device  2  is transferred to the contact plate  7 . The outer wall  6  may partially or wholly enclose the components of the needle assembly replacement device  1 . A perimeter of the opening  8  may be contoured to guide the medicament delivery device  2  into a desired position (e.g., perpendicular to the contact plate  7  with a needle assembly  3  attached thereto in the opening  8 ). For example, a sloped ridge may partially or entirely encircle the opening  8  to guide the medicament delivery device  2  into the opening  8  and ensure that the delivery device  2  remains in the desired position while the needle assembly replacement device  1  is in use. The contact plate  7  is axially moveable relative to the chassis  5  along a number of guiding rails  9  in a longitudinal direction L. A spring  13  is adapted to apply a biasing force on the contact plate  7  relative to the chassis  5 . 
         [0038]    In an exemplary embodiment, two gripping wheels  10  are coupled to the guiding rails  9  via struts so as to move in the longitudinal direction L with the contact plate  7 . Each gripping wheel  10  is coulpled to a lead screw  11  which is fixed to the chassis  5 . The lead screw  11  includes a helical channel adapted to mate with a radial projection on an inner circumference of the gripping wheel  10 . Thus, as the gripping wheel  10  moves axially relative to the lead screw  11 , the engagement of the channel and the radial projection causes the gripping wheel  10  to rotate relative to the lead screw  11 . Each gripping wheel  10  may include a frictional surface/material on part or all of its outer circumference. 
         [0039]    In an exemplary embodiment, a needle support  14  is slidably coupled to the chassis  5  and arranged to slide in a transversal direction T relative to the longitudinal direction L. The needle support  14  is adapted to hold a cover  4 ′ for an unused needle assembly  3 . As shown in  FIG. 4 , a first cam track  15  is arranged on the needle support  14  and adapted to receive a first follower pin  16  on a leg connecting two guiding rails  9 . The leg is coupled to the contact plate  7  such that axial movement of the contact plate  7  results in axial movement of the leg. The first cam track  15  comprises a longitudinal portion  15 . 1  parallel with the longitudinal direction L and an angled portion  15 . 2  having a slope such that the needle support  14  moves in a first transverse direction I on downward movement of the first follower pin  16  when the first follower pin  16  is engaged in the angled portion  15 . 2 . 
         [0040]    Referring back to  FIG. 1 , in an exemplary embodiment, a needle wedge  17  having a ramp  18  is slidably coupled to the chassis  5  and arranged to slide in the transversal direction T relative to the longitudinal direction L. The ramp  18  may be arranged to fit within a through-slot in the needle support  14  when the needle wedge  17  moves in the first transversal direction I, and the needle wedge  17  may have a rail which mates with a slot on the needle support  14  (or vice-versa) for aligned translation of the needle wedge  17  relative to the needle support  14 . A second cam track  19  is arranged on the needle wedge  17  and is adapted to receive a second follower pin  20  coupled to the leg. As shown in  FIG. 4 , the second cam track  19  comprises a first longitudinal portion  19 . 1  in parallel with the longitudinal direction L, a first angled portion  19 . 2  having a first slope followed by a second angled portion  19 . 3  having a second slope followed by a third angled portion  19 . 4  having a third slope followed by a second longitudinal portion  19 . 5  in parallel with the longitudinal direction L. The slopes of the first angled portion  19 . 2  and the second angled portion  19 . 3  are such that the needle wedge  17  moves in the first transversal direction I inwardly on downward movement of the second follower pin  20  when the second follower pin  20  is engaged in the first or second angled portion  19 . 2 ,  19 . 3 . The second slope of the second angled portion  19 . 3  may be steeper then the first slope of the first angled portion  19 . 2 . The third slope of the third angled portion  19 . 4  may be such that the needle wedge  17  continues movement in the first transversal direction I on upward movement of the second follower pin  20  when the second follower pin  20  is engaged in the third angled portion  19 . 4 . 
         [0041]    Referring back to  FIG. 1 , the contact plate  7  is in a first axial position P 1 , pressed against the outer wall  6  under the force of the spring  13 . As shown in  FIG. 3 , when the contact plate  7  is in the first axial position P 1 , the gripping wheels  10  are in a first angular position R 1 , engaging a cover  4  of the needle assembly  3 . In an exemplary embodiment, the gripping wheels  10  are substantially circular with a groove  12  formed in the periphery. 
         [0042]    In the exemplary embodiment illustrated in  FIG. 1 , the cover  4  from a used needle assembly  3  is retained by the gripping wheels  10  of the needle assembly replacement device  1 , and the used needle assembly  3  is engaged to the delivery device  2 . 
         [0043]    As shown in  FIG. 2 , the distal end of the medicament delivery device  2  with the used needle assembly  3  is inserted in the needle assembly replacement device  1  through the opening  8 . The cover  4  may have one or more elements (e.g., ridges, ribs, threads, etc.) which engage corresponding elements on a needle hub  3 . 1  of the needle assembly  3 . The engagement of the elements and corresponding elements ensure that the needle assembly  3  does not rotate relative to the cover  4 . 
         [0044]      FIG. 4  is a schematic detail view of an exemplary embodiment of the needle support  14  and needle wedge  17  when the contact plate  7  is in the first axial position P 1 . 
         [0045]    As shown in  FIG. 5 , when an axial force is applied to the medicament delivery device  2 , the contact plate  7  is pushed into the chassis  5  to a second axial position P 2  against the biasing force of the spring  13 . As the contact plate  7  moves axially, the gripping wheels  10  rotate in a first rotational direction due to their interface with the lead screws  11 . Rotation of the gripping wheels  10  causes rotation of the cover  4  and the needle hub  3 . 1  therein relative to the deliver device  2 , thus unscrewing the needle assembly  3  from the medicament delivery device  2 . When the contact plate  7  is in the second axial position P 2 , the gripping wheels  10  are in second angular position R 2 , as shown in  FIG. 6 , maintaining a hold on the cover  4  but having rotated enough to disengage the used needle assembly  3  from the delivery device  2   
         [0046]      FIG. 7  shows the positions of the needle support  14  and needle wedge  17  when the contact plate  7  is in the second axial position P 2 . The first follower pin  16  has travelled through the longitudinal portion  15 . 1  of the first cam track  15 , and the second follower pin  20  has travelled through the first longitudinal portion  19 . 1  of the second cam track  19 . Because portions  15 . 1  and  19 . 1  are parallel to the axis of translation of the contact plate  7 , the needle support  14  and the needle wedge  17  do not move when the contact plate  7  moves from the first axial position P 1  to the second axial position P 2 . 
         [0047]    As shown in  FIG. 8 , as the contact plate  7  is pushed into the chassis  5 , the cover  4  (with the used needle assembly  3  therein) is rotated in conjunction with rotation of the gripping wheels  10 . 
         [0048]    As shown in  FIG. 10 , when the contact plate  7  is in a third axial position P 3 , the gripping wheels  10  are in a third angular position R 3 , such that the grooves  12  are aligned with the cover  4 , which releases the cover  4  from the gripping wheels  10 . 
         [0049]    As shown in  FIGS. 9 and 11 , when the contact plate  7  is being pushed from second axial position P 2  to the third axial position P 3 , the first follower pin  16  is travelling through the angled portion  15 . 2  of the first cam track  15  in the needle support  14  such that needle support  14  is moved in the first transversal direction I, and the second follower pin  20  is travelling through the first angled portion  19 . 2  of the second cam track  19  in the needle wedge  17  such that needle wedge  17  is moved in the first transversal direction I. Thus, when the cover  4  (and the used needle assembly  3  therein) is released from the gripping wheels  10 , a ramp  22  on the needle support  14  abuts the cover  4  and pushes it in the first transversal direction I through an opening  21  in the wall  6 . In an exemplary embodiment, the slope of the angled portion  15 . 2  of the first cam track  15  substantially equals the first slope of the first angled portion  19 . 2  of the second cam track  19  such that the amount of transversal travel of the needle support  14  and the needle wedge  17  is equal once the first follower pin  16  is engaged in the angled portion  15 . 2  and the second follower pin  20  is engaged in the first angled portion  19 . 2 . When the contact plate  7  is in the third axial position P 3 , the first follower pin  16  has exited the first cam track  15 , and a new cover  4 ′ containing an unused needle assembly  3  is aligned with the opening  8  and the distal end of the delivery device  2 . Further, because the first follower pin  16  has exited the first cam track  15 , continued translation of the contact plate  7  does not cause any movement of the needle support  14 . 
         [0050]    As shown in  FIG. 12 , when the contact plate  7  is pushed to a fourth axial position P 4 , the needle wedge  17  moves in the first transversal direction I, and the ramp  18  on the needle wedge  17  enters the slot of the needle support  14  and pushes the new cover  4 ′ upwards towards the distal end of the medicament delivery device  2  to a level at which the gripping wheels  10  can interface with the new cover  4 ′. In the fourth axial position P 4 , the second follower pin  20  has reached a lower-most portion of the second cam track  19 , preventing further downward movement of the contact plate  7  and providing a tactile feedback such that force on the delivery device  2  can be released or reduced. 
         [0051]    When the contact plate  7  is in the fourth axial position P 4 , the gripping wheels  10  do not sufficiently engage the new cover  4 ′. 
         [0052]    As shown in  FIG. 14 , when the force on the delivery device  2  is reduced or released, the biasing force in the spring  13  pushes the contact plate  7 . As the contact plate  7  translates axially, the second follower pin  20  is engaged in the third angled portion  19 . 4 , causing the needle wedge  17  to move further in the first transversal direction I and have the ramp  18  push the new cover  4 ′ (and unused needle assembly  3  therein) upward matching the upward travel of the contact plate  7  and medicament delivery device  2 . During this movement, the gripping wheels  10  rotate in a second rotational direction opposed to the first rotational direction and grip (as shown in  FIG. 15 ) the new cover  4 ′ before the axial support by the needle wedge  17  is removed when the second follower pin  20  reaches the second longitudinal portion  19 . 5  of the second cam track  19  in the needle wedge  17 . 
         [0053]    In an exemplary embodiment, the needle support  14  and the needle wedge  17  are biased in a second transversal direction  0  by one or more springs (not shown). As the first follower pin  16  abuts a lateral face  23  of the needle support  14  opposite the ramp  22  and the second follower pin  20  is still engaged in the second longitudinal portion  19 . 5  of the second track  19  in the needle wedge  17 , the needle support  14  and the needle wedge  17  are prevented from moving in the second transversal direction O until the contact plate  7  has travelled upward by a sufficient distance to allow the follower pins  20 ,  16  to disengage the needle wedge  17  and needle support  14 . This is to ensure that the new cover  4 ′ is clear of the needle support  14 . 
         [0054]    As the medicament delivery device  2  and the contact plate  7  move further upward out of the chassis  5 , the thread interface between the gripping wheels  10  and the lead screws  11  cause the gripping wheels  10  to rotate in the second rotational direction. This rotates the new cover  4 ′ (and hence unused needle assembly  3  therein) for engaging the unused needle assembly  3  to the medicament delivery device , as shown in  FIG. 16 . 
         [0055]      FIG. 17  is a schematic perspective view of the needle assembly replacement device  1  during removal of the medicament delivery device  2 . An inner needle cover  24  is still attached to the needle assembly  3 . The presence of the cover  24  may provide a visual feedback that an unused needle assembly  3  has been assembled to the medicament delivery device  2 . The new cover  4 ′ remains in the needle assembly replacement device  1 . 
         [0056]    In alternative exemplary embodiments, the needle support  14  may be arranged to retain more than one new needle assembly  3  in respective new covers  4 ′. 
         [0057]    Those of skill in the art will understand that modifications (additions and/or removals) of various components of the apparatuses, methods and/or systems and embodiments described herein may be made without departing from the full scope and spirit of the present invention, which encompass such modifications and any and all equivalents thereof.