Patent Publication Number: US-2022233780-A1

Title: Actuation mechanism

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. patent application Ser. No. 16/301,341 filed Nov. 13, 2018, which is a U.S. National Phase Application pursuant to 35 U.S.C. § 371 of International Application No. PCT/EP2017/060966 filed May 9, 2017, which claims priority to Swedish Patent Application No. 1650741-0 filed May 27, 2016. The entire disclosure contents of these applications are herewith incorporated by reference into the present application. 
    
    
     TECHNICAL AREA 
     The present disclosure relates to an actuation mechanism for a medicament delivery device and in particular a so called pen injector provided with a number of specific features. 
     BACKGROUND 
     Many injectors on the market, especially pen-injectors, are provided with a functionality to allow multiple doses to be given from a medicament container. In many instances the dose quantity is fixed and is set just before a dose is to be delivered. Thus, a manual dose setting sequence is first performed and then a manual dose delivery sequence is performed. 
     Document US 2009/0137964 discloses such a medicament delivery device having a dose setting member that is turned. The dose setting member is connected to a dose indicator barrel having a set of numerals that are visible through a window in a housing part. A nut member provided with a thread segment is arranged between the dose setting member and an internal thread on the housing. The length of the internal thread corresponds to the length that the piston rod has to travel in order to empty the medicament container and a stop on the thread segment engages an end wall of the internal thread when the medicament container is empty which thereby prevents the user for setting a dose larger than the remaining content of the medicament container. 
     SUMMARY 
     The aim of the present disclosure is to provide a reliable and simple solution of preventing setting of doses of medicament that are larger than the remaining quantity of a medicament container. 
     This aim is solved with a drive mechanism comprising the features of the independent patent claim. Preferable embodiments of the disclosure form the subject of the dependent patent claims. 
     According to a main aspect of the disclosure, it may comprise an actuation mechanism to be used with a medicament delivery device. The actuation mechanism may comprise a plunger rod arranged to act on a stopper of a medicament container; an actuator arranged slidable and connected to the plunger rod for acting on the stopper when said actuator is operated by displacing it in a longitudinal direction of the actuation mechanism. Further a dose setting mechanism may be rotatably arranged for setting a dose, wherein the dose setting mechanism may comprise a generally tubular activator sleeve provided with a spirally extending groove on its outer surface. 
     Favourably the groove is arranged with a length corresponding to the total amount of medicament to be delivered in a number of doses contained in the medicament container. Also, the groove may be provided with an end wall. A stop ring may be arranged coaxial with the activator sleeve, wherein the activator sleeve may be arranged with a follower positioned in the groove, wherein the follower is arranged to abut the end wall of the groove when the total amount has been delivered. 
     With this solution, it is ascertained that no dose larger than the remaining dose of the medicament container can be set or delivered. This is important because a user could otherwise get the impression that a full dose has been given since he/she was able to set a dose before delivery. 
     According to one solution, the stop ring may be arranged non-rotatable but movable in a longitudinal direction of the module. It is then thus moved in the longitudinal direction each time the activator sleeve is rotated due to the spirally extending groove. 
     Further, in order to be able to set a dose of medicament, the dose setting mechanism may preferably comprise a grip part arranged releasably connected to activator sleeve. It is then easy for a user to operate the grip part in order to set a dose. The grip part is preferably releasable and in particular after a dose has been set and a dose is to be delivered. This is because the activator sleeve is turning also during dose delivery and it is not desirable that the grip part is rotating at that stage. 
     As stated above, the activator sleeve rotates somewhat also during dose delivery, i.e. when the actuator is manually pressed in the proximal direction. The rotation of the activator sleeve has the feature of locking the activator in a depressed state after completed dose delivery. Because of this, the activator sleeve may comprise protrusions arranged to interact with the actuator such that activator sleeve is rotated when the actuator is operated. The protrusions of the activator sleeve then cooperate with ledges of the actuator, which ledges are arranged inclined in relation to the longitudinal direction. 
     As stated above, the actuator is locked after dose delivery and this may be performed in that the actuator is arranged with locking elements arranged to cooperate with the protrusions of the activator sleeve such as to lock the actuator after operation for delivering a dose of medicament. The locking elements may comprise ledges arranged generally transversal to said longitudinal direction. The locking elements may also comprise ramped or wedge-shaped sections on which the protrusions of the activator sleeve may slide before coming in contact with the generally transversal ledges. 
     In order to provide a subsequent operation of the actuation mechanism, the transversal ledges may be interconnected with the inclined ledges such that turning of the activator sleeve moves the protrusions from a locking position to a release position of the actuator. According to a further aspect, the actuation mechanism may further comprise a drive member acting on the actuator for urging it in a distal direction of the actuation mechanism when the actuator is released. 
     In addition, the actuation mechanism may further comprise a toggle sleeve operably arranged between the actuator and the plunger rod for urging the plunger rod in a proximal direction during operation of the actuator. In this respect, the plunger rod may be arranged with threads, a driver non-rotatably connected to the plunger rod, which driver is arranged with protrusions on its outer surface, that the toggle sleeve is arranged with surfaces inclined in relation to the longitudinal direction, causing a rotation of the plunger rod when the actuator and the toggle sleeve are moved in the proximal direction. 
     These and other aspects of, and advantages with, the present disclosure will become apparent from the following detailed description of the disclosure and from the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       In the following detailed description of the disclosure, reference will be made to the accompanying drawings, of which 
         FIG. 1  is an exploded view of a medicament delivery device comprising a drive mechanism according to the present disclosure, 
         FIG. 2  is a cross-sectional view of the medicament delivery device of  FIG. 1 , 
         FIG. 3  is a detailed view of a medicament container fastener of the device of  FIG. 1 , 
         FIG. 4  is detailed views of components comprised in the medicament delivery device of  FIG. 1 , 
         FIG. 5  is an exploded view of a drive mechanism according to the present disclosure, 
         FIG. 6  is a detailed view of components comprised in the medicament delivery device of  FIG. 1 , 
         FIG. 7  is a detailed view of components comprised in the medicament delivery device of  FIG. 1 , 
         FIG. 8  is a detailed view of components comprised in the medicament delivery device of  FIG. 1 , 
         FIG. 9  is a detailed view of components comprised in the medicament delivery device of  FIG. 1 , 
         FIG. 10  is a detailed view of components comprised in the medicament delivery device of  FIG. 1 , 
         FIG. 11  is a detailed views with housing parts removed showing different functional stages of the medicament delivery device, 
         FIG. 12  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 13  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 14  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 15  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 16  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 17  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 18  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 19  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 20  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 21  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, 
         FIG. 22  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device, and 
         FIG. 23  is a detailed view with housing parts removed showing a different functional stage of the medicament delivery device. 
     
    
    
     DETAILED DESCRIPTION 
     In the embodiment shown in the drawings, the medicament delivery device comprises a generally tubular distal housing part  10  and a generally tubular proximal housing part  12 . In this regard it is to be understood that the housing may comprise a number of different sub-parts depending on manufacturing and assembly aspects. The proximal end of the distal housing part is arranged with attachment elements such that proximal housing part  12  can be attached. Thereby the distal end of the proximal housing part  12  is arranged with a central passage having a diameter generally corresponding to the diameter of the proximal end of the distal housing part  10  and provided with corresponding attachment elements. In this regard it is to be understood that the attachment elements may have a number of different shapes and functions for attaching the medicament container holder to the housing, such as threads, bayonet couplings, snap-in protrusions etc., if the proximal housing part  12  is to be releasably attached to the distal housing part  10 . If the proximal housing part  12  is to be permanently attached, the attachment elements may comprise wedge-shaped grip protrusions and recesses that allow assembly but prevent disassembly, welding, glue, etc. A protective cap  14  is also provided for releasably covering the proximal housing part  12 . 
     The proximal housing part  12  is designed as a medicament container holder and is arranged to house a generally tubular elongated medicament container  16 , which is provided with a resilient movable stopper  18 . The proximal housing part  12  may be transparent or may be provided with openings or windows so that the medicament container  16  and its content may be viewed. The proximal end of the medicament container  16  is provided with a neck portion  22  arranged with a penetrable septum  24 ,  FIG. 2 . The neck portion  22  is arranged to fit into a neck portion  26  of the proximal housing part  12 . The neck portion  26  of the proximal housing part  12  is provided with attachment elements for a medicament delivery member that may be an injection needle provided with a hub having corresponding attachment elements. In this regard the attachment elements may be threads, bayonet couplings, snap-in attachments, luer-connections, just to mention a few options. Further, a generally ring-shaped medicament container fastener  30  is arranged to abut a distally directed surface of a medicament container  16  placed in the proximal housing part  12  with a proximally directed surface. The medicament container fastener  30  is urged in the proximal direction by a compression spring  31  arranged between the medicament container fastener  30  and a proximally directed surface of an end wall  32  of the distal housing part  10 . The movement in the proximal direction of the medicament container fastener  30  is limited by radially outwardly directed protrusions  34  on an outer surface of the medicament container fastener  30  cooperating with cut-outs  36  of proximally directed ledges  38  on the proximally directed surface of the end wall  32 ,  FIG. 4 . 
     The medicament delivery device further comprises an actuation mechanism  40 ,  FIGS. 1 and 5 . The actuation mechanism  40  comprises an elongated plunger rod  42 ,  FIGS. 5 and 6 , provided with threads  44  on its outer surface, which threads  44  are arranged to cooperate with corresponding thread segments  46  in a central passage  48  in the proximal end wall  32  of the distal housing part  10 ,  FIG. 4 . The plunger rod  42  is arranged with two longitudinally cut-away sections  50 , on opposite sides of the plunger rod  42 , forming support surfaces. The plunger rod  42  is arranged to fit into a generally tubular driver  52 . The inner surface of the driver  52  is arranged with two sets of longitudinally extending ledges  54  wherein the plunger rod  42  fits into the space  45  between these sets of ledges  54  such that the support surfaces of the cut-away sections  50  of the plunger rod  42  will be in contact with side surfaces of the ledges  54 , whereby the plunger rod  42  is rotationally locked to the driver  52  but linearly movable in the longitudinal direction. The proximal end of the driver  52  is provided with ramped surfaces  56  that end in ledges  58 , which ledges  58  interact with ledges  60  on ramped surfaces  62  on a distally directed surface of the end wall  32  of the distal housing part  10  surrounding the threaded central passage  48 . 
     The outer surface of the driver  52  is further arranged with two outwardly directed protrusions  64  arranged on opposite sides of the driver  52 ,  FIG. 6 . These protrusions  64  are arranged to interact with edge surfaces  66  of cut-outs  68  at a proximal part of a generally tubular toggle sleeve  70 , which is positioned coaxial and outside the driver  52 . The edge surfaces  66  of the toggle sleeve  70  have a certain configuration as seen in  FIG. 7 , having a first section  66   I  with an inclination alpha. The first section  66   I  is then interrupted by a second section  66   II  with a very steep inclination beta and in an opposite direction as the first section  66   I . The second section  66   II  then ends in a further first section  66   I . The first and second sections are arranged twice around the proximal end of the toggle sleeve  70 . The function of the protrusions  64  and the edge surfaces  66  will be described in detail below. The toggle sleeve  70  is further arranged with an end wall  72  at its distal end and wedge-shaped cut-outs  74  on a distal end area of the toggle sleeve  70 , the function of which will be described below. A compression spring  76 , hereafter named toggle sleeve spring,  FIGS. 3 and 5 , is arranged with a distal end in contact with a proximal surface of the end wall  72  of the toggle sleeve  70 , and with a proximal end in contact with distally directed surface of an annular flange  78  of a generally tubular washer  80 ,  FIG. 2 , wherein the washer body extends into the toggle sleeve spring  76 . A proximally directed surface of the flange  78  of the washer  80  is in contact with a distal end surface  82  of the driver  52 . 
     Coaxial with and outside of the toggle sleeve  70  is a generally tubular actuator  84 ,  FIG. 8 . The actuator  84  is arranged with a number of radially outwardly directed ledges  86  at a proximal part thereof, which ledges  86  are configured to fit in between pairs of longitudinally extending ledges  88 ,  FIG. 4 , on an inner surface of the distal housing part  10 , thereby creating a rotational lock between the actuator  84  and the distal housing part  10  but allowing axial movement of the actuator  84 . The actuator  84  is further arranged with a number of sets of ledges  90  on its outer surface, which ledges  90  have a certain extension as will be explained. A first section  90   I  of the ledges is arranged facing the distal direction and with a steep inclination in relation to the longitudinal direction of the actuator  84 . At one end of the first section, a second section  90   II  is arranged, extending in the circumferential direction. A third section  90   III  is connected to the second section  90   II , extending with an inclination in relation to the longitudinal direction L. Parallel to the third section  90   III , a fourth section  90   IV  is placed, thus having an inclination in relation to the longitudinal direction L. 
     A fifth section  90   V  then connects to the third section  90   III , extending in the circumferential direction. The fifth section  90   V  then connects to a sixth section  90   VI  extending in the longitudinal direction. The sixth section  90   VI  then connects to a seventh section  90   VII  extending in the circumferential direction, which in turn connects to the first section of a subsequent set of sections  90 . An area between the fourth section  90   IV  and the sixth section  90   VI  is arranged as a wedge-shaped ramp  92  having a distally directed ledge  94 . The sets of ledges are repeated two times around the circumference of the actuator  84 . Distally of the ledges  90  are a number of longitudinally extending ledges  96 . The distal end part  98  of the actuator  84  is arranged with a somewhat dome-shaped end wall  100  wherein the distal end part  98  of the actuator  84  is arranged to protrude out of the distal end of the medicament delivery device and to act as a push button for a user, as will be described. A proximal surface of the end wall  100  is further arranged with proximally directed wedge-shaped protrusions  102 , which protrusions  102  are arranged to cooperate with the wedge-shaped cut-outs  74  on the toggle sleeve  70 ,  FIG. 8 . 
     At the distal end of the housing a generally tubular activator  104  is arranged,  FIG. 9 . It has a distal grip part  106  that when connected to the distal housing part  10  is placed distally of the distal housing part  10  and having a diameter somewhat larger than the diameter of the distal housing part  10 . The side surfaces of the grip part  106  may be arranged with grip elements, such as longitudinally extending ridges  108 . The grip part  106  is further arranged with two planar surfaces  110  directed inwards and towards each other in the radial direction. Two proximally directed tongues  112  extend from the planar surfaces  110 . The tongues  112  are arranged with cut-outs  114 . The grip part  106  is arranged to fit onto a distal area of a generally tubular proximal part  116  of the activator  104  wherein the planar surfaces  110  of the grip part  106  are abutting corresponding planar surfaces  118  of the proximal part  116  that are facing radially outwards. The planar surfaces  118  of the proximal part  116  are arranged with wedge-shaped protrusions  120  that are intended to fit into the cut-outs  114  of the tongues  112  and lock the grip part  106  to the proximal part  116  when the two parts are assembled. 
     The proximal tubular part  116  of the activator  104  is arranged with an outwardly, circumferentially extending, ledge  122  in a proximal area thereof. Further, the grip part  106  is arranged with a proximally directed edge  124  such that when the grip part  106  is assembled with the proximal part  116 , an annular recess is formed between the ledge  122  and the edge  124 . A locking ring  126  is positioned rotationally in the recess between the ledge  122  and the grip part  106 . The locking ring  126  is arranged with protrusions  128  on its outer surface, which protrusions  128  are arranged to fit into recesses  130 ,  FIG. 4 , on an inner surface of the distal housing part  10 . Further, the outer surface of the locking ring  126  is arranged with ledges  132 , which ledges  132  fit into longitudinally extending recesses  134  on the inner surface of the distal housing part  10 ,  FIG. 4 . This locks the activator  104  to the distal housing part  10 , allowing rotation of the activator  104 , as will be described. 
     Further, the proximal part  116  of the activator  104  is provided with a number of resilient arms  136  that extend in the circumferential direction of the activator  104 . The arms  136  have a resiliency in the radial direction. The free ends of the arms  136  of the activator  104  are designed to be in contact with an inner surface of the locking ring  126  so as to cause a frictional resistance so as to avoid unwanted spontaneous movement of the activator  104  if the medicament delivery device for example is shaken. Further, the inner surface of the locking ring  126  is arranged with ledges  138  having surfaces in the circumferential direction, which ledges  138  cooperate with the free ends of the arms  136  so that the activator  104  can only be turned in one direction. Also, the inner surface of the proximal part  116  is arranged with two curved surfaces  140  provided at opposite sides and facing each other, having a curvature generally corresponding to the outer surface of the actuator  84 . The curved surfaces are limited in the circumferential direction by longitudinally extending guide ledges  142 , the function of which will be described below. 
     Further, at the proximally directed end surface of the activator  104 , a number of proximally directed wedge-shaped protrusions  144  are arranged. These wedge-shaped protrusions  144  are designed to interact with at least one corresponding wedge-shaped protrusion  146  on a distal end surface of a generally tubular activator sleeve  148 ,  FIGS. 9 and 10 , which activator sleeve  148  is arranged rotational and slidable inside the distal housing part  10  and coaxial and outside the actuator  84 . The inner surface of the activator sleeve  148  is arranged with two inwardly directed protrusions  150  at a proximal area thereof, which protrusions  150  are designed with a number of side surfaces having different inclinations as seen in  FIG. 9 . The protrusions  150  are designed to be in contact with and follow the ledges  90  of the actuator  84  as will be described. Adjacent the protrusions  150 , cut-outs  151  are provided, enabling some flexing in the radial direction of the protrusions  150 . 
     The activator sleeve  148  is further arranged with a spirally extending groove  152  on its outer surface,  FIG. 10 . The groove  152  has an end wall  154  at the proximal end of the activator sleeve  148 . The groove  152  is intended to interact with at least one ledge  156  arranged on an inner surface of a stop ring  158 , which stop ring  158  is positioned coaxially outside the activator sleeve  148 . The outer surface of the stop ring  158  is arranged with longitudinally extending ledges  160 , which ledges  160  are designed to fit into the longitudinally extending recesses  134  on the inner surface of the distal housing part  10  as seen in  FIG. 4 . This connection provides a rotational lock of the stop ring  158  while allowing movement in the longitudinal direction. The stop ring  158  is further arranged with proximally directed tongues  162 , which tongues  162  are arranged to cooperate with ledges  164  on either side of the recesses  134  for providing guiding stability of the stop ring  158  as will be described. 
     The disclosure is intended to function as follows. When the device is delivered to a user, the plunger rod  42  is in its most distal position as shown in  FIG. 2 . Further the actuator  84  is in its most proximal position, with only a short part of the distal push button part  98  extending through the distal end of the medicament delivery device. The actuator  84  is locked in that position by the protrusions  150  of the activator sleeve  148  being in contact with the distal surface of the ledge  90   VII  of the actuator,  FIG. 11 . This prevents movement of the actuator  84  in the distal direction against the urging force of the toggle sleeve spring  76  that is tensioned between the toggle sleeve  70  and the actuator  84 . The activator  104  is in an initial position where the ends of the resilient arms  136  of the proximal part  116  are resting against the ledges  138  of the wedge-shaped protrusions on the inner surface of the locking ring  126 . 
     The medicament delivery device could either be delivered to a user with a medicament container  16  already mounted in the proximal housing part  12  and thus ready to use or be delivered without a medicament container mounted and possibly also with the proximal housing part  12  unconnected to the distal housing part  10 , wherein the user has to put a medicament container  16  inside the proximal housing part  12  and then attach the proximal housing part  12  to the distal housing part  10  of the medicament delivery device. The container fastener  30  with the spring  31  is now pressing the medicament container in the proximal direction, thereby reducing the risk of rattling of the medicament container. 
     In either way, when the medicament delivery device is to be used, the protective cap  14  is removed and a medicament delivery member is attached to the neck portion  26  of the proximal housing part  12 . When the medicament delivery member is an injection needle, the attachment causes a distal pointed end of the injection needle to penetrate the septum  24  of the medicament container, thereby causing a flow passage through the needle from the interior of the medicament container  16 . 
     In order to unlock and activate the medicament delivery device, the user turns the grip part  106 , which is counter clockwise in the embodiment shown. Any rotation in the opposite direction is prevented by the arms  136  of the proximal part  116  engaging the ledges  138  of the wedge-shaped protrusions of the locking ring  126 . In the embodiment shown, there are three ledges  138  of the wedge-shaped protrusions along the inner circumference of the locking ring  126  with thus a 120 degree displacement between the ledges  138 , and consequently the activator  104  is turned 120 degrees per step, as will be described in more detail below. 
     The initial mutual positions of the proximal part  116  and the activator sleeve  148  are shown in  FIG. 11 . In this position, the at least one wedge-shaped protrusion  144  of the proximal part  116  is in full contact with the space between the protrusions  146  of the activator sleeve  148 , causing a rotational lock between the two components. When the grip part  106  with the proximal part  116  is turned, the activator sleeve  148  follows, whereby its protrusions  150  will slide along the ledge  90   VII  of the actuator  84  until the protrusions  150  come to the steep ledge  901 ,  FIG. 11 . This will enable the actuator  84  to be moved in the distal direction by the toggle sleeve spring  76  acting between the distal end of the driver  52  and the toggle sleeve  70 , which in turn is abutting the distal end surface of the actuator  84 , which in turn causes the push button part of the actuator  84  to extend in the distal direction through the distal end of the medicament delivery device. During the turning of the activator sleeve  148 , the ledge  156  of the stop ring  158  will slide in the spiral groove  152  of the activator sleeve  148 . 
     The user now stops turning the activator  104  but since the protrusions  150  of the activator sleeve is in contact with the steep inclined ledge  901  of the actuator  84 , the activator sleeve  148  continues to rotate because the actuator  84  is rotationally locked to the housing by the ledges  86  cooperating with the ledges  88  of the distal housing part  10 . When now the proximal part  116  is stationary and the activator sleeve  148  is rotating, the inclined surface of the at least one wedge-shaped protrusion  146  of the activator sleeve  148  will cooperate with the inclined surface of the wedge-shaped protrusions  144  of the proximal part  116 , whereby the activator sleeve  148  is forced in the proximal direction. The rotation of the activator sleeve  148  is stopped when the protrusions  150  are moved in contact with the circumferential ledge  9011  of the actuator  84 , which stops the movement in the distal direction of the actuator  84 ,  FIG. 12 . The push button part  98  of the actuator  84  is protruding out of the distal end of the medicament delivery device as seen in  FIG. 12 . When the actuator  84  is moved in the distal direction, the ledges  96  on the outer surface of the actuator will be positioned parallel to the guide ledges  142  of the proximal part  116  of the activator  104 , thereby preventing any turning of the activator  104 . 
     When the actuator  84  is moving in the distal direction as described above, so is the toggle sleeve  70  since they are in contact with each other because the toggle spring is acting on the toggle sleeve  70 , in turn acting on the actuator  84 . In the initial position the protrusions  64  of the driver  52  are positioned in the junction between the first and second sections  66   I  and  66   II  of the edge surfaces  66  as seen in  FIG. 13 . When now the toggle sleeve  70  is moving in the distal direction together with the actuator  84  the protrusions  64  will slide along the first section  66   I ,  FIG. 14 , and because it has an inclination β in relation to the longitudinal direction, the toggle sleeve  70  will turn in relation to the driver  52 . The driver  52  is prevented from turning in the anti-clockwise direction due to the ledges  58  of the driver  52  cooperating with the ledges  60  of the end wall  32  of the housing. The turning of the toggle sleeve  70  will cause it to move somewhat in the proximal direction in relation to the actuator  84  because of the cooperation between the ramped cut-outs  74  of the toggle sleeve  70  and the wedge-shaped protrusions  102  of the actuator  84 ,  FIG. 15 . During continued movement of the toggle sleeve  70  in the distal direction, the protrusions  64  of the driver  52  will come out of contact with the first section  66   I  whereby the toggle sleeve  70  will be turned back to the initial position because of the cooperation between the ramped cut-outs  74  and the wedge-shaped protrusions  102  as seen in  FIG. 16 . 
     The device is now activated and ready to deliver a dose of medicament. If a medicament delivery member has not been attached before, it may be attached now to the proximal end of the medicament delivery device. The proximal end of the medicament delivery device is now placed at a dose delivery site, and if the medicament delivery member is an injection needle, a penetration is performed at the dose delivery site. The next step is to deliver a dose of medicament. The user then presses on the push button part  98  of the actuator  84  so that it moves in the proximal direction. This will cause the inclined ledge  90   IV  of the actuator  84  to be moved in contact with the protrusions  150  of the activator sleeve  148 ,  FIG. 17 . This will in turn move the activator sleeve  148  in the proximal direction whereby the wedge-shaped protrusions  146  of the activator sleeve  148  are moved out of contact with the wedge-shaped protrusions  144  of the proximal part. Any turning of the activator  104  will thus not affect the medicament delivery device. At the same time, the activator sleeve is turned due to the inclination of the ledge  90   IV . 
     As the actuator  84  is moved in the proximal direction, so is the toggle sleeve  70 . This movement will cause the first section  66   I  of the cut-outs  68  to come in contact with the protrusions  64  of the driver,  FIG. 18 , and continuous movement of the toggle sleeve  70  will cause the protrusions  64  to slide along the inclined first section  601 ,  FIG. 19 , whereby the driver  52  is turned in the clockwise direction. The turning is not obstructed by the ledges  56  of the driver  52  and the ledges  62  of the end wall  32  of the housing. The turning of the driver  52  will in turn cause a turning of the plunger rod  42  because of the rotational lock between them and since the plunger rod  42  is threadedly connected to the passage  48  of the end wall  32  of the housing  10 , the plunger rod  42  will be moved in the proximal direction,  FIG. 18 , whereby it will act on the stopper  18  for expelling a dose of medicament through the medicament delivery member. 
     During the movement in the proximal direction of the actuator, the protrusions  150  of the activator sleeve  148  will enter the ramped part and at the end of the movement of the actuator  84  pass the ledge  94 , causing the actuator  84  to be locked in the depressed position,  FIG. 20 . The passing of the ledge  94  by the protrusions  150  is facilitated by the flex obtained by the cut-outs  151 . There is further a safety feature, should the user during the pressing of the actuator  84  in the proximal direction suddenly release the actuator  84  before completing the dose delivery sequence. In this case only a part of the amount of medicament has been delivered. The toggle sleeve spring  76  will then try to force the actuator  84  in the distal direction. However, this is prevented in that the protrusion  150  will be moved in contact with the circumferentially extending ledge  90   V ,  FIG. 21 , thereby preventing further movement. If not stopped, it would otherwise lead to the actuator  84  being again moved to a fully extended position, whereby it would be possible to deliver a new full amount of medicament. This is now prevented by the ledge  90   V . The user may now press on the partly extending push button part  98  for delivering the remainder of the dose of medicament, after which the actuator  84  is locked as described above. 
     The medicament delivery device may now be removed from the dose delivery site, the medicament delivery member removed and discarded in a safety container and the protective cap  14  re-connected to the proximal end of the medicament delivery device. The above mentioned sequences of dose setting and dose delivery are repeated until the medicament container  16  is empty and as described above, the ledge  156  of the stop ring  158  is moved a distance along the spiral groove  152  of the activator sleeve  148  for each dose setting operation, whereby the stop ring  158  is moved in the proximal direction. In order to prevent setting a dose that is larger than the remaining dose quantity of the medicament container, the length of the spiral groove  152  around the circumference of the activator sleeve  148  corresponds to the total amount of medicament in the medicament container. Thus, the setting of the last dose may be limited by the ledges  156  of the stop ring  158  abutting the end wall  154  of the groove  152 ,  FIGS. 22 and 23 , preventing further turning of the activator  104  and the activator sleeve  148 . This means that no dose larger than the remaining amount of the medicament container  16  can be set. 
     It is to be understood that the embodiment described above and shown in the drawings is to be regarded only as a non-limiting example and that the disclosure may be modified in many ways within the scope of the patent claims.