Abstract:
Device for dispensing a substance having: a dispensing element through which the substance can be dispensed, a displaceable protective element for the dispensing element, a drive element that is coupled with the protective element and a feedback element which can generate a signal when or after a predefined quantity or the entire quantity of the substance to be dispensed has been dispensed characterized in that the feedback device is coupled with the drive element.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a Continuation of International Patent Application No. PCT/CH2014/000034 filed Mar. 20, 2014, which claims priority to European Patent Application No. 13160614.7 filed Mar. 22, 2013, the entire contents of each are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The invention concerns a substance dispensing device, in particular, an injection device or an autoinjector, which features a signaling device to indicate, for example, optically, acoustically, and/or tactilely, when a substance has been released or a dispensing has taken place, completely or at least, to a predefined extent. A substance which can, for example, be dispensed automatically can be a fluid product or a medication, which may, for example, be liquid, paste-like or gel-like. 
       BACKGROUND 
       [0003]    From WO 2011/123024 A1, a medication dispensing device with a drive device acting on a medication container so as to hold the drive device in a pretensioned state is known. An activation device interacts, with the holding device, to release the drive device from the pretensioned state. A feedback device can interact both with the holding device and with the drive device in order to generate a signal, which indicates that the medication has been completely ejected. 
         [0004]    WO 94/11041 discloses an autoinjector with a first unit, which brings about an automatic needle penetration and which controls a second unit, which produces the release of the medication, so that the release of the medication is begun only if the needle penetration was carried out completely. 
         [0005]    WO 2013/016832 A1 discloses an injection device for the automatic dispensing with a needle protective device, which can be displaced from a distal to a proximal position and from there, to a needle protective position and with a drive device that can move in a housing, which is driven to a dispensing position with a drive means, and with a rotating sleeve, which can be rotated from a first to a second position and has a first profile, which is in an operative connection with a second profile of the drive device. The drive device rotates through the first profile and the second profile, the rotating sleeve from the first to the second position. 
       SUMMARY 
       [0006]    One object of the invention is to make available a substance dispensing device or an injection device, in which the user triggers an injection in a simple manner and can be informed by the device as to the correct functional course. 
         [0007]    This object is attained by the device and method according to the independent claims, with advantageous further developments defined in the dependent claims. 
         [0008]    A device in accordance with the invention for administering a substance is preferably an autoinjection device, which has an energy storage or a drive element, with which dispensing can be automatically carried out. Preferably, force or energy which is supplied or applied externally, for example, by a user, is not required. The energy storage or drive element advantageously stores the complete energy required for an automatic release of the substance. Such an energy storage or drive element can, for example, be a spring. This spring may be incorporated, into the injection device in an energy-storing state—that is, for example, compressed, pulled apart, or also twisted—and can release energy by an energy releasing process—that is, for example, by relaxation if the spring was incorporated compressed or twisted, or under torsional stress, or also by contraction if the spring was incorporated when pulled apart. The energy release advantageously takes place directly or indirectly—that is, via intermediate components—on a piston rod or pressure element which presses a stopper of a syringe and can push this stopper into the syringe. 
         [0009]    Optionally, the energy storage element or another separate energy storage element can be provided, in order to automate the process of inserting a needle. The insertion process, however, can also be done manually—it can, for example, be undertaken by a user-without using energy stored in the injection device for that purpose. 
         [0010]    The administration device has a release element, for example, a needle, by means of which the substance can be released. The needle is coupled with the container for the substance to be released in a known manner, so that, for example, upon displacing the aforementioned stopper, the substance passes through the needle and is released and injected at the distal front end of the substance. 
         [0011]    A protective element is provided for the release element, for example, a sleeve which is to be pushed beyond the release element, which, for example, may be pushed axially, parallel to the longitudinal direction of a needle that serves as the release element. The protective element can surround the release element, for example, radially, prior to the release, and also protrude beyond the release element in distal direction, so that the release element is essentially or completely surrounded or covered by the protective element. The protective element thereby advantageously has a passage opening for the release element, through which the release element can leave the protective area of the protective element. The release element can be moved actively through the protective element and also the protective element can be removed actively from the release element—that is, for example, pushed back in a proximal direction—so as to release at least the distal area of the release element. 
         [0012]    The protective element is coupled with a drive element which is or may be designed separately from the aforementioned, optionally provided drive elements or is designed, for example, as a second or third drive spring within an injection device. The protective element can be driven by this drive element. For example, the drive element can cause the protective element to be brought or pushed, over the release element once again after the substance has been released. Optionally, the drive element can also serve as a holding element, for example, in order to hold the protective element, in a protective position, over or around the release element before and/or after a substance release. The drive element can be incorporated, in a relaxed state or in a tensioned or loaded—that is, energy-containing or—storing, state in the injection device, wherein this energy can be used to drive the protective element. If the drive element is incorporated in the injection device in a state in which it does not store energy, or stores a small amount of energy, then during a functional course before driving the protective element, the drive element must be provided with energy by another element—that is, for example, by a user or one of the aforementioned other drive elements, for example, a tensioned dispensing spring. 
         [0013]    A feedback device of the injection device can generate a signal if a predefined quantity or the entire quantity of the substance to be dispensed was released. The signal that is generated can be an acoustic signal—that is, for example, a “click” sound, which is generated if a moving element strikes another element. It is also possible for the acoustic signal to be, for example, a mechanically generated friction or scratching sound, when two elements are moved relative to one another. The signal can also be a tactile or haptic signal—that is, a signal which can be felt by a user. Such a signal can, for example, also be created by a stop of one element on another element, or a vibration or friction signal when two elements move, relative to one another. Furthermore, the signal can be a visual signal, such as a color signal or a color area of the feedback device, which is displaced, for example, in a certain area. For example, the feedback device can carry a signaling color, which is moved out of a visible area, or is moved into a visible area, in order to indicate that a substance release has not yet taken place, or also that it has been concluded. 
         [0014]    According to the invention, the feedback device is coupled with the drive element with which the protective element is also coupled. For example, the feedback device is a stop element—that is, a pin or a sleeve—which is accelerated by a needle protective sleeve spring or is moved against a stop, wherein the needle protective sleeve spring acts on a needle protective element with pressure or exerts force on it, in order to bring or to hold in a protective position the needle protective element relative to the release element or to the needle. 
         [0015]    The feedback element can, for example, strike the housing of the injection device and therefore move relative to it, wherein it is also possible that the feedback strikes any other part. Preferably, the feedback element is accelerated by the aforementioned drive element over a predefined distance, for example, straight or in a rotational movement, in order to produce a strike, at a certain speed, and thus a noticeable feedback signal. 
         [0016]    The device according to the invention can have another separate, second feedback device, which, for example, signals the beginning of the substance release. It is conceivable that both feedback devices can also be implemented in one element. 
         [0017]    As already mentioned, the administration device can also have a second, third, fourth, or other drive element or energy storage element, which, for example, makes energy available to bring about the substance release and/or energy for the carrying out of a needle penetration. This second or additional drive element is provided separately from the drive element which is coupled with the feedback device and can, for example, be functionally, completely separate from the feedback drive element. It is also possible that such an additional drive element releases or transfers energy to the feedback-drive element. 
         [0018]    A modulation or dampening element can also be provided on the feedback element, by means of which the feedback coupling—that is, for example, a feedback sound or a tactile feedback signal—can be influenced or modified. For example, straps or stop surfaces or dampening means may be provided, which delay or decelerate an impact or strike of the feedback device on a surface or an impact part. Likewise, it is possible for a modulation element to increase the strike surface, in order to increase the signal strength that is to be generated. 
         [0019]    The feedback element can preferably be held by a releasable holding device until the end of the substance release, so that, for example, the feedback element is triggered or released and, for example, is driven by a drive element only if the substance release is complete or has been carried out to a specific, previously defined extent—that is, for example, the piston rod was pushed to a stipulated dispensing point. 
         [0020]    As mentioned above, the feedback coupling device can be a stop element which, for example, is accelerated or driven along a straight path, in order to strike, at the end, at a stopping place, and thus, create a feedback signal. It is also possible for the feedback device to be, for example, a rotating element, which, for example, carries out a rotational movement after the stipulated ending of the complete substance release and creates a rotational strike. For this, for example, a torsional moment of a used spring—that is, for example, a used needle protective spring or also an injection spring—can be used. 
         [0021]    In accordance with another aspect, the invention refers to a method for the release of a substance from a device that is described above, wherein the substance is automatically released by means of a first drive element and a feedback signal for the signaling of the, for example, ended substance release by means of a feedback element, driven by a separate, second drive element, is generated. The drive elements are consequently separate devices or functional units—that is, for example, two separately provided springs which can, however, be coupled with one another, in order to transfer energy from a spring—such as, from a drive spring—to another spring—that is, for example, the feedback spring. 
         [0022]    This transfer of energy or force can take place before, during, or after the substance release. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  is a cross-sectional view along a longitudinal axis of a first embodiment of an injection device for the illustration of the concept. 
           [0024]      FIG. 2  is an exploded view of the injection device shown in  FIG. 1 . 
           [0025]      FIGS. 3A and 3B  are cross-sectional views of the injection device shown in  FIG. 1 , in the delivery state, rotated relative to one another by 90°. 
           [0026]      FIGS. 3C to 3G  is the execution of the radial inside of the locking sleeve (180° execution) for the illustration of the relative movement of the engaging cams of the mechanism holder and the click pin. 
           [0027]      FIGS. 4A and 4B  are cross-sectional views of the injection device shown in  FIG. 1  in the inserted state, rotated by 90°, if the injection device is or was pressed onto the injection site. 
           [0028]      FIGS. 4D to 4H  are detailed views of the locking sleeve and the principle of the needle protective locking for the illustration of the relative movement of the intervening cams of the mechanism holder and the click pin. 
           [0029]      FIGS. 5A and 5B  are cross-sectional views of the injection device shown in  FIG. 1 , rotated relative to one another by 90°, before the beginning of the dispensing. 
           [0030]      FIGS. 6A and 6B  are cross-sectional views of the injection device shown in  FIG. 1 , rotated, relative to one another, by 90° after the dispensing has been completed. 
           [0031]      FIGS. 7A and 7B  are cross-sectional views of the injection device shown in  FIG. 1 , rotated, relative to one another, by 90° after the dispensing has been completed and the strike of a click element, confirming this completed dispensing. 
           [0032]      FIG. 8  is an exploded view of a second embodiment of an injection device. 
           [0033]      FIGS. 9A and 9B  are cross-sectional views of the injection device shown in  FIG. 2  in the delivery state, rotated, relative to one another, by 90°. 
           [0034]      FIGS. 10A and 10B  are longitudinal cross-sectional views of the injection device shown in  FIG. 2  in the inserted state, rotated, relative to one another, by 90°, if the injection device was pressed onto the injection site. 
           [0035]      FIGS. 11A and 11B  are cross-sectional views of the injection device shown in  FIG. 2 , rotated, relative to one another, by 90°, after the dispensing has been completed and the signaling of the end of the injection by the strike of the release sleeve on the end cap has taken place. 
           [0036]      FIGS. 12A and 12B  are cross-sectional views, rotated, relative to one another, by 90°, with regard to a third embodiment of an injection device in the delivery state. 
           [0037]      FIGS. 13A and 13B  are cross-sectional views of the injection device shown in  FIGS. 12A and 12B , rotated, relative to one another, by 90°, with regard to the injection device after a completed penetration and dispensing movement and confirmation of the complete dispensing by striking the release sleeve on the bottom of the mechanism holder. 
           [0038]      FIG. 14A  shows a fourth embodiment of an injection device in the delivery state, in which the syringe spring makes available the energy for the end click (end-of-injection click). 
           [0039]      FIG. 14B  shows the injection device, in accordance with  FIG. 14A , in the dispensed state before the end click. 
           [0040]      FIG. 15A  shows an embodiment of a functional unit of an end-click unit of an injection device in the delivery state, in which a rotational strike is generated by a torsional moment of the injection spring. 
           [0041]      FIG. 15B  shows the functional unit of  FIG. 15A  with a generated end click. 
           [0042]      FIG. 16A  shows an embodiment of a functional unit of an injection device in the delivery state for the generation of an end click by the energy of the needle protective sleeve spring. 
           [0043]      FIG. 16B  shows the functional unit of  FIG. 16A  after the generated end click. 
       
    
    
     DETAILED DESCRIPTION 
       [0044]      FIGS. 1 and 2  show a concept of a first embodiment of an injection device, in accordance with the invention. The injection device comprises a sleeve-shaped housing  2 , on which a syringe holder  1 , a mechanism holder  5 , and an end cap  12  are stationary in the housing—that is, do not move with respect to the housing  2 . The syringe holder  1 , the mechanism holder  5 , and the end cap  12  can be locked in place, cemented, soldered, bolted, or snapped in the housing  2  or also they can be designed, as a whole, as a single piece with the housing  2 . A preferably already prefilled syringe  13  can be taken in the syringe holder  1  and be held by it. The syringe  13  has a holding space  13   b , which is limited by a stopper  13   a  which can be displaced along the longitudinal axis of the syringe  13 , and in which a substance to be released is contained, which presses out from this space with the displacement of the stopper  13   a  in the distal longitudinal direction of the syringe  13  (in  FIG. 1  to the left) and which can be released, in a known manner, by a needle  14  arranged on the front side of the syringe  13 . The needle  14  is surrounded by a needle protective cap  15  in the starting state shown in  FIG. 1 , in which there is, for example, a needle protective element  15   a , which may be elastic or made of rubber. The needle protective cap  15  can be removed, together with the rubber element  15   a  contained therein, by means of which the cap removal element  4  placed thereon, in order to release the needle  14 , which, in the starting position shown, is also surrounded by the front side of a needle protective sleeve  3  that can be moved in and again out in the axial direction of the housing  2 . 
         [0045]    An injection spring  9  serving as an energy storage unit or drive means is pretensioned and in the starting state, is held between the piston rod  7  and the click pin  6 , wherein the injection spring  9  is supported within the piston rod  7  and is surrounded by the piston rod  7 , and the piston rod  7  presses on a distal bottom element  7   b  or is supported against it. In the proximal direction, the injection spring  9  is held by a proximal bottom or plate element  6   d  of a click pin  6  or is supported against it. The click pin  6  has a guide pin  6   e  in the axial direction, which is arranged, in the inserted state, within the injection spring  9  and is connected with the plate element  6   d  on the proximal end, from which the release snap arms  6   a  extend, running approximately parallel to the guide pin  6   e , which are designed in an elastic manner or so they can be deformed—that is, they can be moved radially outwards or inwards. The inner cams  6   b  engage in indentations or openings  7   a  of the piston rod  7 , so that, in this state, an axial displacement between the click pin  6  and the piston rod  7  is not possible by the force of the pretensioned injection spring  9 . The spring package, consisting of the click pin  6 , the piston rod  7 , and the injection spring  9 , can thus not be pressed apart. A radial release of the release snap arms  6   a  outwards is prevented by the axially displaceable sleeve  8 , which is in the area of the outer cams  6   c  around the click pin  6 ; the outer cams  6   c  are opposite its inside or next to it. 
         [0046]    The injection spring  9  is preferably a pressure spring or coiled spring, which preferably stores or can absorb at least the energy for the dispensing sequence and which is, as a tensioned spring, inserted into the injection device. 
         [0047]    The needle protective device  3 , which is designed as a sleeve-shaped element and is supported so it can be displaced relative to the housing  2 , has a passage opening  3   d  on its distal front side, through which the needle  14  can pass or which moves back, in the axial direction, along the needle  14  or can be pushed into the housing  2 . Extending in the axial direction are two opposite arms  3   a , which are located, relative to the passage opening  3   d , in the proximal direction. 
         [0048]      FIGS. 3A and 3B  are cross-sectional views of the injection device in the delivery state, rotated, relative to one another, by 90°. As already mentioned, the injection spring  9  is pretensioned between the piston rod  7  and the click pin  6 . The piston rod  7  is held against the force of the injection spring  9 , which exerts a force acting on the piston rod  7  in the distal direction, by the inner cams  6   b  of the release snap arms  6   a  of the click pin, as can be seen from  FIG. 3B . The locking sleeve  8  prevents a movement of the cams  6   b  and the release snap arms  6   a , directed radially outwards. 
         [0049]    An end-click element  11  is pressed or held in the proximal direction by a needle protective sleeve spring  10 , which presses on a ring-shaped radial expansion  11   b  of the end-click element  11 . 
         [0050]    On the opposite side, the needle protective sleeve spring  10  is supported on a flange  8   g  of the locking sleeve  8 . The needle protective sleeve spring  10  can already be pretensioned, just like the injection spring  9 , or it can be inserted, relaxed, into the injection device. The locking sleeve  8  is proximally shifted on the arms  3   a  of the needle protective sleeve  3 , which is held against a displacement in a distal direction via proximal cams  1   a  of the spring holder  1 , which is fixed in the housing; the cams protrude radially outwards and engage in recesses or passages of the arms  3   a.    
         [0051]    As shown in  FIG. 3A , the end-click element  11 , pressed or held proximally, holds the piston rod  7  in the proximal starting position shown by means of cams  11   a , which are arranged on spring arms  11   c , protruding radially inwards, and which engage in indentations or openings  7   c  of the piston rod  7 ; in the starting position, the distal front side of the piston rod  7  is at a distance from the proximal rear of the stopper  13   a.    
         [0052]    The end-click element  11  is in the starting or delivery state with its proximal front side on the plate-shaped bottom  12   b  of the end cap  12 , which is stationary in the housing or is snapped on the housing  2  by means of the snaps  12   a.    
         [0053]    The syringe  13  inserted in the injection device is held, toward the front, in the syringe holder  1  by means of a shoulder support  1   b  or projections  1   b  of the syringe holder  1 , which protrude radially inwards, and is secured by means of a ring or a housing tapering  2   b  in the housing  2 . This ring or the housing tapering  2   b  prevents a radial release or escape of the syringe holder  1   b . The syringe holder  1  is, on the front side, on ribs or projections  2   e  of the housing  2 , which protrude radially inwards. 
         [0054]    Cams  1   c , which protrude radially outwards, on spring arms  1   d  of the syringe holder  1 , which is stationary in the housing, engage in an axially running groove  3   e  of each arm  3   a  of the needle protective sleeve  3  and from the aforementioned radially protruding cams  1   a , are as far in the axial direction as approximately the length of the axial groove  3   e , so that the needle protective sleeve  3  is held against an axial displacement by the cams  1   a  and  1   c , which, at a distance axially from one another, engage in the axial groove  3   e , wherein the cams  1   c  provided on the spring arms  1   d , move radially inwards with an application of a relatively small pressing force on the needle protective sleeve  3  and make possible a proximal pushing of the needle protective sleeve  3  into the housing. 
         [0055]      FIGS. 3C-3G  show an inner execution of 180°—that is, a half of the locking sleeve  8 , wherein areas protruding radially inwards are shown crosshatched. The positions of the locking sleeve  8  are thereby explained in connection with the movements of the needle protective sleeve  3 . 
         [0056]    The locking sleeve  8  is shown in the starting state of the needle protection in  FIG. 3C . The guide areas or grooves of the locking sleeve  8  located between the crosshatched areas, enable an intervention of a cam  6   c  of the click pin  6 , directed radially outwards. Furthermore, a cam  5   c  of the mechanism holder  5 , protruding outwards in the radial direction, meshes into an axially running groove  8   a , which is provided on the radial inside of the locking sleeve  8 , and is engaged with it, so that a rotation of the locking sleeve  8 , relative to the mechanism holder  5 , which is stationary in the housing, is prevented. In the position shown, the locking sleeve  8  can, however, be pushed in the axial direction. 
         [0057]    Before the beginning of use of the injection device, the needle  14  must be released, and to do this, the cap removal element  4  is removed, in the distal direction, from the distal front side of the injection device. As one can see from  FIG. 3A , the snap hooks  4   a  of the cap removal element  4  snap in behind the rear edge of the needle protective cap  15 . Ribs  2   f  of the housing  2  which are provided on the radial outer side of the snap hooks  4   a  and are next to these prevent a release or escape of these snap hooks  4   a , so that by a pulling on the cap removal element  4 , it is possible to remove the needle protective cap  15  in the distal direction. The elastic or rubber needle protection  15   a , fastened within the needle protective cap  15 , is thereby also removed together with the needle protective cap  15 , so that the needle  14  is released. The cap removal element  4  is held on the needle protective sleeve  3  by means of a snap element  4   b , which engages behind a radially protruding snap holder  3   b . Upon removal of the cap removal element  4 , a force which can overcome the snap holder  3   b ,  4   b  must be applied. 
         [0058]    After the removal of the cap removal element  4 , together with the needle protective cap  15 , the needle  14  is released, but is still surrounded by the distal sleeve area of the needle protective sleeve  3 , which projects also in the distal direction beyond the tip of the needle  14 , so that the needle  14  is still protected by the front or distal part of the needle protective sleeve  3 . 
         [0059]    If the injection device, situated in the ready-to-use state after the removal of the cap removal element  4 , with its distal front side—that is, the distal front area of the needle protective sleeve  3 —is pressed onto a puncture site, then by this pressure which is usually applied onto the housing  2  by a user holding the housing  2 , the needle protective sleeve  3  is displaced, in the proximal, axial direction, into the housing  2 , wherein the needle  14 , which is stationary relative to the housing  2 , is released and pierces the puncture site. 
         [0060]    This state is shown in the cross-sectional views of  FIGS. 4A and 4B , which are rotated relative to one another by 90°. With an appropriate pressure exerted on the housing  2  in the distal direction, the needle protective sleeve  3  is inserted through the contact surface surrounding the puncture site into the housing  2 , to the stop  2   c  limiting the insertion of the needle protective sleeve  3 , which takes place simultaneously with the puncture of the needle  14  into the injection site. 
         [0061]    By the insertion of the needle protective sleeve  3 , as shown in  FIGS. 3B and 4B , the locking sleeve  8 , next to the proximal end of the arms  3   a  of the needle protective sleeve  3 , is likewise pushed in the proximal direction, relative to the housing  2 , wherein the needle protective sleeve spring  10 , which is supported between the aforementioned contact surfaces of the locking sleeve  8  and the end-click element  11 , is compressed or tensed. 
         [0062]    In the starting position shown in  FIG. 3C , the cam  6   c , protruding radially outwards and lying on an elastic release snap arm  6   a  of the click pin  6 , is still outside a guide area on the radial inside of the locking sleeve  8  and only after the puncture, is it moved in the axial direction, relative to the locking sleeve  8 , by an axial displacement of the locking sleeve  8 , relative to the housing  2 , into an engagement area, as shown in  FIG. 3D  and in  FIG. 4D , in which the cam  6   c , with a front bevel in the axial direction, is next to a bevel  8   b  of the bar  8   h . Since, in this state, a force acting in the distal direction (in  FIG. 3E , to the left) is exerted by the needle protective sleeve spring  10  on the locking sleeve  8 , the system—present on the bevel  8   b —on the cam  6   c  of the click pin  6 , which is held against an axial displacement by the pressing force of the injection spring  9 , leads to a rotation operation of the locking sleeve  8  in the direction shown by the arrow P. By the rotation of the locking sleeve  8 , relative to the housing  2 , the locking sleeve  8  is also twisted relative to the cam  5   c  of the mechanism holder  5 , so that the cam  5   c  either engages in the axially running locking path  8   c , shown in  FIG. 3E  and  FIG. 4E , or is about to engage. 
         [0063]    If the housing  2  of the injection device is pressed onto the injection site to the extent that the needle protective sleeve  3  is almost completely pushed or is completely pushed into the housing  2 , as shown in  FIGS. 4A and 4B , the automatic injection is released. The locking sleeve  8  is thereby axially pushed in the proximal direction, by the adjacent arms  3   a  of the needle protective sleeve  3 , within the housing, to such an extent that the release snaps  6   a  of the click pin  6  are released by the locking sleeve  8 , which has been pushed away and is no longer lying around the outer cams  6   c , wherein the release snap arms  6   a  can move radially outwards. Since the piston rod  7  is acted on with a force, by the injection spring  9 , in a distal direction, relative to the housing, the inner cams  6   b  are pressed out from their engagement in the openings  7   a  of the piston rod  7 , which is supported by the bevels  6   f  and  7   d , shown in  FIG. 5B . 
         [0064]    The release snap arms  6   a  of the click pin  6 , which are correspondingly pressed radially outwards, are shown in  FIG. 5B . In this way, the piston rod  7  is released and driven by the force of the pretensioned injection spring  9 , can move, relative to the housing  2 , within the housing in the distal direction onto the stopper  13   a . Moreover, the click pin  6  is also released and pressed by the force of the injection spring  9  axially, within the housing  2 , in the proximal direction, strikes, to the proximal front surface of the pin  6 , the distal bottom surface of the end cap  12 , as shown in  FIGS. 5A and 5B . A start signal or start click is produced by the striking of the click pin  6  on the end cap  12 . Dampening elements can be placed between the end cap  12  and the click pin  6 , wherein the striking or impact of the click pin  6  can be delayed or decelerated and thus, the start signal can be modified. For the purpose, as shown in  FIGS. 3A and 3B , for example, a squeeze rib  12   c  and a counter-rib  12   c ′, which is, at an angle, opposite the squeeze rib  12   c , can be placed between the end cap  12  and the click pin  6 . Furthermore, additional dampening straps or snaps  12   d  and opposing dampening ribs  12   d ′ can be placed. 
         [0065]    As already described, the needle protective locking is activated ( FIG. 4D ) by the pressing of the snap arms  6   a.    
         [0066]      FIGS. 5A and 5B  show cross-sectional views of the injection device rotated relative to one another by 90°, after the start click was carried out, which signals acoustically and tactilely the beginning of the injection, and the activation of the signal, described below, for the indication of the end of the injection (end-of-injection click). 
         [0067]    The piston rod  7  is moved by the force of the relaxing injection spring  9  in the distal direction and comes to a stop at the stopper  13   a , on which the piston rod  7  exerts a force acting in the distal direction by the injection spring  9 , which is proximally supported, wherein the stopper  13   a  is pushed into the syringe  13 , in order to displace the substance contained in the syringe  13 , which is released or injected by the inserted needle  14 . 
         [0068]    As shown in  FIG. 4A , the piston rod  7  is still connected with the end-click element  11  by means of the cams  11   a , which engage in corresponding indentations or recesses of the piston rod  7 , before the displacement for the impingement on the proximal side of the stopper  13   a . This engagement is secured by the mechanism holder  5 , surrounding the click element arms  11   c , which prevents the click element arms  11   c  from moving radially outwards and thus can trigger the engagement in the piston rod  7 . If the piston rod  7  is pushed in the distal direction to such an extent that the outer cams  11   d  of the click element arms  11   c  can engage in the release openings of the mechanism holder  5 , as shown in  FIG. 5A , then the click element arms  11   c  are pressed to the extent that they do not change with the piston rod  7 , so that the displacement-secure coupling with the piston rod  7  is triggered. In this way, the end-click element  11  is held back. Since the protective sleeve spring  10  is supported, at its proximal end, against the end-click element  11 , the needle protective sleeve spring  10  is tensioned by the displacement of the end-click element  11  in the distal direction, as can be seen from  FIGS. 5A and 5B . Thus, there is an energy transfer from the relaxing injection spring  9  to the tensioning needle protective sleeve spring  10 . 
         [0069]      FIGS. 6A and 6B  show longitudinal cross-sectional views of the injection device rotated relative to one another by 90°, after the dispensing of the substance. The piston rod  7 , which is no longer held back, was thereby pushed into the syringe  13  by the force of the injection spring  9 , wherein the stopper  13   a  was moved in a distal direction until it was at the end of the glass body and the substance was thus completely dispensed or released. 
         [0070]    The one movement of the cams  11   a , directed radially inwards, was pushed onto the piston rod  7 , hindering the click element arms  11   c , which is placed on the inner cams  11   a  of the end-click element  11  in the state shown in  FIGS. 5A and 5B , in the distal direction, after the dispensing, as shown in  FIG. 6A , to such an extent in the distal direction that the click element arms  11   c  are again released. Since the end-click element  11  is impinged by pressure by the needle protective sleeve spring  10 , in the proximal direction, the holding engagement of the click element arms  11   c  is detached by means of the outer cams  11   d  in the mechanism holder  5  and releases the end-click element  11 , as shown in  FIG. 7A . The end-click element  11  is moved in the proximal direction after release by the needle protective sleeve spring  10 , until it strikes the bottom  12   b  of the end cap  12  and causes an end click. This end click can be heard and can be perceived tactilely also by a user, in order to thus signal the end of the injection. The end click is consequently not brought about by the injection spring  9 . 
         [0071]      FIGS. 7A and 7   b  show longitudinal cross-sectional views of the injection device rotated relative to one another by 90° with an end click or after an end click has been carried out. If the injection device is removed from the injection site after a dispensing has been carried out, then the needle protective sleeve  3  is moved together with the locking sleeve  8  pressing on it, both of which are acted on by the needle protective sleeve spring  10 , in the distal direction, with a force to the front—that is, relative to the housing  2 , axially in the distal direction. 
         [0072]    By the force of the needle protective sleeve spring  10 , the locking sleeve  8  is pushed axially in the distal direction (in  FIG. 3E , to the left, and  FIG. 4E ), wherein this axial displacement triggers a rotation of the locking sleeve  8  by means of the bevels  8   b  and the cam  6   c  and, in this way, the cam  5   c  is guided to engage with the axially running groove  8   c  and the locking sleeve  8  is thus secured with respect to twisting during this displacement. If the locking sleeve  8  has been pushed to such an extent that the cam  5   c  comes to a stop at the bevel  8   i  on the proximal end of the groove  8   c , as shown in  FIGS. 3F and 4F , then further pressure exerted on the locking sleeve  8 , in the distal direction, leads to a further rotation of the locking sleeve  8  in the direction shown by the arrow P ( FIGS. 3F ,  4 F and  3 G,  4 G), wherein the cam  5   c  lines up at the step  8   f  of the locking sleeve  8  and thus, prevents a pushing back of the locking sleeve  8  and the needle protective sleeve in the proximal direction (in  FIG. 4H , to the right). 
         [0073]    A centering cam  3   c , provided on an individual arm  3   a  of the needle protective sleeve  3  engages, in this state, in a centering groove  8   e  of the locking sleeve  8  and thus prevents the locking sleeve  8  from rotating back. Thus, in this state, the needle protective sleeve  3  is pushed out beyond the needle  14  and secured against a pushing back by the cam  5   c  which lines up at the step  8   f  of the locking path  8   c.    
         [0074]      FIG. 8  shows an exploded view of a second embodiment of an injection device. 
         [0075]      FIGS. 9A and 9B  show longitudinal cross-sectional views rotated relative to one another, by 90°, in the delivery state. The injection spring  9  is pretensioned between the piston rod  7  and the end cap  12 . A release sleeve  16  lies, toward the front via ribs  16   c , on the mechanism holder  5 . The mechanism holder  5  and the end cap  12  are firmly connected with one another. The piston rod  7  is held, in the distal direction, by a triggering snaps  16   a  of the release sleeve  16  and is secured by means of the locking sleeve  8 . A cam  5   c  of the mechanism holder  5  engages with an axially running groove  8   a  of the locking sleeve  8  and prevents a twisting of the locking sleeve  8 , relative to the mechanism holder  5 . 
         [0076]    The needle protective sleeve spring  10  is pretensioned between the locking sleeve  8  and the release sleeve  16 . The mechanism holder  5  and the end cap  12  are stationary in the housing and are connected with the housing  2 , for example, with snaps or by locking in place. 
         [0077]    The locking sleeve  8  lies on straps or arms  3   a  of the needle protective sleeve  3 , which is held, toward the front via a cam  1   a , on the syringe holder  1 . The release sleeve  16  is held, toward the back via the triggering snaps  16   a  of the release sleeve  16 , secured by the locking sleeve  8 , on the piston rod  7 . 
         [0078]    Just as described in the first embodiment, the syringe  13  is secured by means of a shoulder support  1   b  and by means of a ring or a housing tapering  2   b.    
         [0079]    The removal of the needle protective cap  4  is likewise carried out as described in the first embodiment example. 
         [0080]      FIGS. 10A and 10B  show longitudinal cross-sectional views of the injection device, rotated, relative to one another, by 90°, in the pierced state, if the injection device is pressed on the injection site. The needle protective sleeve  3  is pressed into the housing  2  to the stop  2   c , while the needle is inserted into the injection site. The needle protective sleeve  3  displaces the locking sleeve  8 , relative to the mechanism holder  5  and the release sleeve  16 , wherein the needle protective sleeve spring  10  is tensed or compressed. 
         [0081]    The injection is triggered by the complete insertion of the needle protective sleeve  3  into the housing  2 . The locking sleeve  8  is thereby pushed in the proximal direction (in  FIG. 10 , to the right), relative to the housing  2 , the mechanism holder  5 , and the release sleeve  16 , wherein the triggering snaps  16   a  are released. By the force of the injection spring  9 , the triggering snaps  16   a  are pressed and free in a distal direction to the front, against the movement of the piston rod  7 . The release sleeve  16  is then held toward the rear, on the mechanism holder  5 , via the snap arms  16   b.    
         [0082]      FIGS. 11A and 11B  show longitudinal cross-sectional views of the injection device rotated relative to one another by 90° after the dispensing and after the click for the signaling of the end of the injection has been carried out (end-of-injection click). The piston rod  7  was thereby moved in the distal direction by the force of the injection spring  9 , wherein the piston rod presses on the stopper  13   a  and moves it in the distal direction until it is at the end of the glass body of the syringe  13 . At its proximal end, the piston rod  7  has a slit  7   b , wherein the snap arms  16   b  of the release sleeve at the end of the injection are released and the blocking of the release sleeve  16  is lifted toward the rear. 
         [0083]    As soon as the snap arms  16   b  of the release sleeve  16  are released by the slit  7   b  of the piston rod  7 , the snap arms  16   b  are deflected, wherein the release sleeve  16  is moved to the rear by the force of the needle protective sleeve spring  10  and strikes the bottom  12   c  of the end cap  12  and produces the end click. 
         [0084]    The needle protective locking takes place in the same manner as described in the first embodiment example, wherein the deflected triggering arms are located on the release sleeve  16  and not on the click pin  6 , so that in this regard, reference is made to the above description. 
         [0085]      FIGS. 12A and 12B  show longitudinal cross-sectional views of a third embodiment of an injection device rotated relative to one another by 90° in the delivery state. The injection spring  9  is pretensioned between the piston rod  7  and the release sleeve  16 . The release sleeve  16  is held by the snap arms  16   b  on the mechanism holder  5  and secured by means of the piston rod  7 . The piston rod  7  is held toward the front by the triggering snaps  16   a  and secured by means of the locking sleeve  8 . The cam  5   c  of the mechanism holder  5  engages with the axially running groove  8   a  of the locking sleeve  8  and prevents a twisting of the locking sleeve  8 , relative to the mechanism holder  5 , which is stationary in the housing. 
         [0086]    The needle protective sleeve spring  10  is pretensioned between the locking sleeve  8  and the mechanism holder  5 . The mechanism holder  5  is locked by snaps with the housing  2 . The locking sleeve  8  lies on the arms  3   a  of the needle protective sleeve  3 , which is held toward the front on the syringe holder  1  via the cams  1   a.    
         [0087]    As described in the embodiment above, the syringe  13  is supported in the syringe holder  1  and the housing  2 . 
         [0088]    The removal of the cap removal element  4  for the removal of the needle protective cap  15  takes place as described above. 
         [0089]      FIGS. 13A and 13B  show longitudinal cross-sectional views of the injection device rotated relative to one another by 90° which was pressed on the injection site; the contents of the syringe were dispensed and signaling of the end of the injection was carried out. 
         [0090]    First the needle  14  is inserted. The needle protective sleeve  3  is pressed into the housing  2  to the stop  2   c . The needle protective sleeve  3  displaces the locking sleeve  8  relative to the mechanism holder  5  and the release sleeve  16 , wherein the needle protective sleeve spring  10  is tensed. 
         [0091]    The injection is triggered by the complete pushing in of the needle protective sleeve  3  into the housing  2 . The locking sleeve  8  is thereby pushed in the proximal direction, relative to the housing  2 , the mechanism holder  5 , and the release sleeve  16 , wherein the triggering snaps  16   a  are released. By the force of the injection spring  9 , the triggering snaps  16   a  are pressed and freed to the front, against the movement of the piston rod  7 . 
         [0092]    By the force of the injection spring  9 , the piston rod  7  was moved in the distal direction, wherein the piston rod  7  presses on the stopper  13   a  and moves it to such an extent in the distal direction that it is next to the end of the glass body of the syringe  13 . On its proximal end, the piston rod  7  has a slit  7   c , wherein the snap arms  16   b  of the release sleeve  16  are released at the end of the injection and the blocking of the release sleeve  16  is lifted in the proximal direction or toward the rear. 
         [0093]    As soon as the snap arms  16   b  of the release sleeve  16  are released by the slit  7   c  of the piston rod  7 , the snap arms  16   b  are deflected, wherein the release sleeve  16  is moved in the proximal direction by the force of the injection spring  9  and strikes the bottom  5   b  of the mechanism holder  5  and produces the end click. 
         [0094]    The needle protective locking takes place in the same manner as described in the second embodiment example. 
         [0095]      FIG. 14   a  shows a longitudinal cross-sectional view of another embodiment of an injection device in the delivery state, in which the injection spring  9  lies, on its distal end, on the inside of the piston rod  7 . On its proximal end, the injection spring  9  is next to a holding sleeve  18 , which is stationary in the housing, which surrounds a click pin  20  and radially, on a proximal site with engagement arms  18   c , through openings of piston rod  7 , engages with them. The click pin  20 , provided for the generation of the end click, is pressed, in the proximal direction (in  FIG. 14A , to the right), on the holding sleeve  18 , via a syringe spring  19 , which presses on distal end surfaces of click pin arms  20 A, wherein the end cap  12  can be a part of the holding sleeve  18 . The syringe spring  19  is supported, in the proximal direction, on the arms  20   a  of the click pin  20  and presses, in the distal direction, on the syringe  13 , in order support it securely in the syringe holder  1  by the acting pressure produced in the distal direction. The arms  20   a  of the click pin  20  are engaged in openings  7   a  of the piston rod  7  by means of cams  20   b  that protrude radially inwards and can be entrained in a distally directed movement of the piston rod  7 , so that the piston rod  7  first entrains the click pin  20  in a distal movement from the delivery state shown in  FIG. 14A . A loosening of the holding connection  7   a ,  20   b  by the radial release of the arms  20   a  is prevented by the holding sleeve  18  surrounding the click pin  20 . 
         [0096]    If the housing  2  of the injection device is pressed so far on an injection site that the needle protective sleeve  3  was almost completely, or completely, pushed into the housing  2 , as shown in  FIG. 14B , the automatic injection is triggered. 
         [0097]    A release sleeve  22  is thereby axially pushed, in the proximal direction, against the force of the needle protective sleeve spring  10  within the housing  2  by the adjacent arms  3   a  of the needle protective sleeve  3  to such an extent that a holding element of the holding sleeve  18 , which engages in the piston rod  7 , is released. 
         [0098]    Since the piston rod  7  is acted on by the injection spring  9  in the distal direction, relative to the housing  2 , the then released piston rod  7  can be moved, in the distal direction, to the stopper  13   a  of the syringe  13  and can move this stopper  13   a  into the syringe  13 , in order to carry out the dispensing. During the dispensing, the click pin  20  is entrained by the piston rod  7 , until the arms  20   a  of the click pin can deflect radially in the free position  18   a  of the holding sleeve  18  and be held on the holding sleeve  18  by this intervention of the cams  20   c  that lie radially and externally on the arms  20   a . A release of the arms  20   a  of the click pin  20 , directed radially inwards, by the piston rod  7 , lying on the inside on the cams  20   b , is impossible until the piston rod  7  has been moved, in the distal direction, to such an extent that the complete dispensing has been carried out. 
         [0099]    At the end of the dispensing, the arms  20   a  of the click pin  20  move radially inwards, since the piston rod  7  was moved, in the distal direction, to such an extent that either, in accordance with a non-depicted embodiment, the piston rod was already completely moved past the cam  20   b , or, as shown in  FIG. 14B , the inside cams  20   b  can be deflected back into openings or free positions on the piston rod  7 . The click pin is thus no longer held by cams  20   c  or  20   b  and accelerates, in the proximal direction, due to the pretensioned syringe spring  19 , in order to strike the holding sleeve  18  or, alternatively, the end cap  12  (not depicted) and thus produce an end click sound. 
         [0100]      FIG. 15A  shows another embodiment of a functional unit for the production of an end click. An injection spring is thereby placed under torsional stress between the piston rod  7  and a stabilization pin or the holding sleeve  18 . The stabilization pin lies on the bottoms of the holding sleeve  18  and runs axially within the injection spring and is secured against twisting with the holding sleeve  18 . 
         [0101]    The piston rod  7  is conducted linearly in a linear guide  18   b  by means of a linear guide element  7   f  in the holding sleeve  18 . 
         [0102]    After the injection has been carried out by an axially forwards directed pushing out of the piston rod  7  from the holding sleeve, as shown in  FIG. 15B , the piston rod  7  is decoupled by the movement of the linear guide element  7   f  out of the linear guide  18   b . By the torsion moment of the injection spring  9 , the piston rod  7  is rotated in the direction defined by the arrow indicating the rotational direction D and with a stop element  7   h  will strike, in the circumferential direction, against the holding sleeve  18  or a linear guide groove inner surface, wherein an end click can be produced. 
         [0103]    Optionally, the piston rod  7  can thereby also rotate on the stopper  13   a  of the syringe  13 . 
         [0104]      FIG. 16A  shows another embodiment of a functional unit for the production of an end click, wherein the energy for the end click is made available by the needle protective sleeve spring  10 . The needle protective sleeve spring  10  is pretensioned between the release sleeve  22  in  FIG. 16A  and the click sleeve  21 . The click sleeve  21  has hooks  21   a , which engage in the holding sleeve  18 . 
         [0105]    The piston rod  7  has a cam  7   g , which presses the hooks  21   a  of the click sleeve  21 , toward the end of the injection, as shown in  FIG. 16B , by passing, proximally to distally (in  FIG. 16B , from right to left), wherein they hang out from the holding sleeve  18  and thus the coupling of the click sleeve  21  with the holding sleeve  18  is loosened. 
         [0106]    The click sleeve  21  is accelerated or moved, by the needle protective sleeve spring  10 , toward the rear or, in a proximal direction, to a stop on the holding sleeve  18 , wherein the end click is produced.