Abstract:
An ampoule holder for receiving an ampoule that has a closure element with a radial projection, the ampoule holder including an ampoule seat and a securing member operably coupled to the ampoule seat, wherein the radial projection of the closure element can be arranged between the ampoule seat and securing member.

Description:
CROSS-REFERENCED RELATED APPLICATIONS 
       [0001]    This application is a continuation of International Patent Application No. PCT/EP2009/056333 filed May 25, 2009, which claims priority to German Patent Application No. 10 2008 025 011.2 filed May 24, 2008, the entire contents of each of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    The present invention relates to devices for injecting, delivering, administering, infusing or dispensing a substance, and to methods of making and using such devices. Such devices often involve container, vial, ampoule, carpoule or reservoir for containing the substance, and more particularly, the present invention relates to an ampoule holder for accommodating an ampoule. The teem ampoule is intended refer to any suitable container-like item, e.g. a vial, etc., from the field of medical technology, in which is contained a product, e.g. a therapeutic or medicinal substance, to be administered using one of the afore-mentioned devices. The term ampoule can refer to both a one-chamber ampoule and multi-chamber ampoules, e.g. a two-chamber ampoule. 
         [0003]    Ampoules are known from the prior art which comprise a cylindrical wall which surrounds a plunger or piston which abuts the inner side of the wall, forming a seal. The plunger can be shifted relative to the wall in the direction of an outlet. The product is situated between the plunger and the outlet. The product container is sealed at the outlet with a seal or septum. The seal can be penetrated by a sharp object, e.g. a needle, cannula, etc. The known ampoules comprise an ampoule neck, at which the ampoule tapers, between the cylindrical casing wall and the seal. The known seals have a smaller outer diameter than the cylindrical casing wall. The smaller diameter of the seal serves to enable the ampoule to be inserted into an ampoule holder from the proximal (rear) opening of the ampoule holder and to be pressed into a fixed fit with the ampoule holder via the tapering part of the ampoule neck. The small diameter of the seal enables the septum to be penetrated with a relatively thin needle. Thin needles have the advantage that they do not cause the patient as much pain during injecting, but the disadvantage that the delivering force which has to be applied to the plunger to deliver the product is relatively large, since the product has to be pressed through a thin channel of the needle. This effect is more significant the higher the viscosity of the product contained in the ampoule. 
       SUMMARY 
       [0004]    The present invention relates to and/or involves drugs, therapeutic substances, medicinal substances and the like, e.g. in liquid or fluid form, for being administered to a patient. The fluid drug can be a homogeneous or heterogeneous fluid. The fluid can be a dispersion, e.g. a suspension or an emulsion. A suspension describes systems consisting of a fluid and particles of solid, such as particles of powder, suspended in it which are practically insoluble. An emulsion is understood to mean a finely distributed mixture of two different fluids which cannot normally be mixed. The fluid or liquid may have a low or a high-viscosity. The present invention also relates to and/or involves suitable containers. 
         [0005]    In some embodiments, a product container in accordance with the present invention can be an ampoule, which also encompasses the term carpoule. An ampoule is described in the following as a representation of suitable product containers. 
         [0006]    In some embodiments, the ampoule comprises a casing which is rotationally symmetrical. The casing, or at least a part of it, is cylindrical or tubular. The distal (front, forward or injection) end of the ampoule comprises a seal which can be penetrated by a needle or similar elongated, pointed object. The ampoule, e.g. its cylindrical casing, is open at the proximal (rear) end, such that a drive member, such as a plunger rod, can act on a plunger or piston which is mounted by or carried in the casing. 
         [0007]    In some embodiments, one or more plungers can be accommodated in the ampoule. The ampoule can thus be a one-chamber ampoule comprising a single plunger or a multiple-chamber ampoule comprising two plungers arranged in succession in the longitudinal direction. 
         [0008]    In a one-chamber ampoule, the fluid product to be administered is between the plunger and the seal. The product can be delivered through the seal by shifting the plunger in the direction of the seal. The plunger, which abuts the inner wall of the casing, forming a seal, can be shifted along the cylindrical part of the casing. 
         [0009]    In a two-chamber ampoule, the drug to be delivered is first merged or mixed from two constituents, before an injection. The two-chamber ampoule generally comprises a first chamber for a first constituent and a second chamber for a second constituent, wherein in the initial state, the two constituents are separated from each other, e.g. by a membrane or a plunger. Storing the constituents separately can increase the storage or shelf life of the drug, since the mixed drug only has a relatively short shelf life. The constituents are combined when being mixed. Mixing can be performed by inserting the two-chamber ampoule into a device which is adapted for such ampoules. The first chamber for the first product constituent is arranged between the seal and the first plunger. The second product constituent is arranged between the first plunger and the second plunger. The second plunger is situated proximally with respect to the first plunger. Both plungers abut the inner circumference of the casing, forming a seal, and can be shifted relative to the casing in the longitudinal direction. 
         [0010]    In some embodiments, one product constituent, e.g. a solid product constituent such as a particulate or powdery product constituent, can be situated in the first chamber. Storing the product constituent in the first chamber in a dry state can increase the shelf life of the product constituent. A fluid product is situated in the second chamber. 
         [0011]    In some embodiments, the two-chamber ampoule can comprise a so-called bypass which comprises a recess, which protrudes or extends radially outwardly in the cylindrical part of the casing. The recess is formed to be elongated, i.e. longer than it is wide, and exhibits a length which is larger than the length of the first plunger. 
         [0012]    A shifting movement of the second plunger can be transferred onto the first plunger via the product constituent situated in the second chamber. In a shifted position of the first plunger, in which the bypass extends beyond the first plunger both distally and proximally, the second plunger can be movable relative to the first plunger. This can reduce the volume between the first plunger and the second plunger, thus enabling the product constituent contained in the second chamber to flow via the bypass into the distal chamber, i.e. the first chamber, or thus pressing the product constituent contained in the second chamber via the bypass into the distal chamber, i.e. the first chamber. The product constituents thus combined can be mixed. To administer the product mixture, the distal facing side of the second plunger can abut against the proximal facing side of the first plunger. The first plunger and the second plunger can then be jointly moved in the distal direction to deliver the product mixture. 
         [0013]    In some embodiments, the seal of the ampoule is formed at its distal (front, forward) end. The seal can comprise a penetrable material or structure which plastically expands when penetrated, in accordance with the injected object, e.g. a needle or a continuation of a needle unit. After the body which has penetrated the seal has been removed, the seal can remain open in accordance with the plastic deformation. The seal comprises a material which can be elastically deformed when penetrated, such that it conforms around the diameter of the penetrating object and abuts it in a fluid seal. When the penetrating object is removed from the seal, the latter can seal itself again in a fluid seal due to its elasticity. The penetration of dirt into the product container and the escape of product from the product container can thus be avoided. If a body is again injected through the seal, the latter can again expand due to its elasticity and again comform against the circumference of the piercing object in a fluid seal. The ampoule can thus also be provided for dispensing product in a number of doses, for each of which a new needle unit is used. A used needle unit can be exchanged for a new one between the injections. 
         [0014]    The elastic part of the seal can be referred to as a septum which can be formed from a synthetic material, natural rubber or another suitable material. 
         [0015]    In some embodiments, the ampoule exhibits an outer diameter on its cylindrical casing. The outer diameter of the cylindrical part of the ampoule can be approximately as large as an inner diameter of an ampoule receptacle, such that the ampoule receptacle can receive, mount or guide the cylindrical part of the casing. 
         [0016]    In accordance with the present invention, in some embodiments, the seal protrudes or extends radially beyond the diameter, i.e. the outer circumference area, of the cylindrical part of the ampoule. The diameter which results in the case of a rotationally symmetrical seal can be larger than the diameter of the cylindrical part of the casing. In some embodiments, the outer diameter of the seal is the maximum diameter of the ampoule as a whole. 
         [0017]    In some preferred embodiments, the seal can comprise at least the septum which exhibits a larger diameter than the cylindrical casing portion and/or protrudes or extends radially beyond the cylindrical casing portion. The seal can also comprise a projection which is formed at the distal end of the casing of the ampoule and protrudes radially beyond the outer circumference of the cylindrical casing part. The projection can be annularly circumferential, such that it can exhibit a larger outer diameter than the cylindrical casing part. The annularly circumferential projection can be referred to as a bulge. The annular projection can be connected, e.g. integrally, to the cylindrical casing portion, directly or indirectly via a portion which exhibits a reduced outer diameter and can be referred to as an ampoule neck. The casing, which is formed from the cylindrical casing part, the annularly circumferential projection and optionally the ampoule neck, can be formed from glass or another suitable material, e.g. a transparent, synthetic material. 
         [0018]    In some embodiments, the ampoule neck can exhibit both an outer diameter which is reduced relative to the outer diameter of the seal and the outer diameter of the cylindrical part and/or an inner diameter which is reduced relative to the inner diameter of the cylindrical casing part. The reduced inner diameter can mean that the plunger can only be shifted as far as the end of the cylindrical part. The length and position of the ampoule holder can be adapted such that the opening and/or the tip of a piercing object which is inserted through the seal can come to rest axially in the region of the ampoule neck and/or the seal. It is thus possible to avoid the plunger abutting against the piercing object or being pressed too firmly against the piercing object when the piercing object is inserted through the septum into the product container. 
         [0019]    In some embodiments, the seal, and/or also the bulge and the septum, can comprise an approximately cylindrical circumferential area in the region of the seal. The seal can comprise an element which connects the septum and the casing, e.g. the annularly circumferential projection or extension, and/or holds them in a connection. This part can surround the septum and the bulge over their outer circumference. The element can also clasp the septum distally and clasp the bulge proximally, to axially secure the septum to the bulge in a fluid seal. The region exhibiting a reduced diameter of the ampoule neck can be advantageous, since the element can clasp the bulge further radially inwardly than without the region exhibiting a reduced diameter. The element can be a remolded (or deformed or deformable) element which during manufacture is correspondingly remolded around the bulge and the septum placed onto the bulge. On the distal facing area of the seal, the element can comprise a breach which is circular and allows direct access to the septum. 
         [0020]    In some embodiments, the septum can comprise a disc-shaped region which exhibits approximately the diameter of the bulge. The septum can also comprise a hollow-cylindrical region which projects or extends proximally from the disc-shaped region. The hollow-cylindrical diameter can exhibit an outer diameter which approximately corresponds to the inner diameter of the casing in the axial region of the bulge. The cylindrical region of the septum can thus serve as a centering aid. The inner space or cavity formed by the hollow-cylindrical part of the septum can serve to accommodate one or more openings of the piercing object, e.g. needle, of an attached needle unit. 
         [0021]    In some embodiments, the bypass of the ampoule can project or extend from the outer circumference of the cylindrical part of the ampoule. 
         [0022]    In some embodiments, the ampoule can be arranged together with an ampoule holder on or in an injection device, wherein the ampoule holder comprises an ampoule receptacle and a fastening member, wherein the radial projection of the seal is arranged, e.g. enclosed, between the ampoule holder and the fastening member. This enables the ampoule holder to be axially fixed, e.g. for a movement in the distal direction and proximal direction. An axial clearance, or gap or shifting, of the product container such as may arise can be reduced or even eliminated, as described further below. 
         [0023]    In some embodiments, the ampoule receptacle can be sleeve-shaped, with an inner diameter which approximately corresponds to the outer diameter of the cylindrical part of the ampoule, such that the ampoule is laterally guided by the ampoule receptacle. The ampoule receptacle can comprise a thread, e.g. an outer thread, which can engage with a corresponding counter thread of an injection device, such that the ampoule receptacle can be axially shifted into the casing, e.g. by a combined rotational and axial movement. Instead of the thread, an axial guide or other components can also be provided, as long as they allow the axial movement of the ampoule receptacle into the injection device. 
         [0024]    In some embodiments, the fastener or fastening member can be fastened or fastenable to the ampoule receptacle. The fastening member can be formed integrally with the ampoule receptacle, or are joined separate parts which together form the ampoule holder. 
         [0025]    In some embodiments, the fastening member can be or comprise a projection which acts on a facing side of the seal of the ampoule, e.g. the distal (forward) facing side. The projection can be a resilient arm, snapper, cam or the like, wherein the projection can extend radially inwardly from without. 
         [0026]    In some preferred embodiments, the ampoule can abut the ampoule receptacle, e.g. the facing side of the ampoule receptacle or a projection on the ampoule receptacle which is directed radially inwardly from an inner circumference, via the proximal side of the seal. In the region where the facing side of the seal is intended to enter into axial abutment, the ampoule receptacle comprises a region exhibiting a reduced inner diameter which is smaller than the outer diameter of the seal and larger than the cylindrical part of the casing. In some embodiments, a facing area of the ampoule receptacle, e.g. the distal end, can provide the abutment for the seal, e.g. its proximal end. 
         [0027]    In some embodiments, the ampoule is inserted or is able to be inserted with its proximal end first, i.e. with its cylindrical casing part to the fore, into the ampoule receptacle through the proximal facing side of the ampoule receptacle. When the ampoule is inserted, the fastening member can be deflected and can snap back in the completely inserted position to axially fix the ampoule in at least one direction. 
         [0028]    In one embodiment, the present invention comprises an ampoule holder for receiving an ampoule that has a closure element with a radial projection, the holder comprising an ampoule seat and a securing member operably coupled to the ampoule seat, wherein the radial projection of the closure element can be arranged between the ampoule seat and securing member. 
         [0029]    In some preferred embodiments, the fastening member can be connected to the ampoule receptacle in a positive fit such that it is rotationally and axially fixed relative to the ampoule receptacle. The ampoule receptacle and the fastening member can comprise mutually engaging elements which mutually engage or latch into or onto each other, e.g. when the fastening member is placed completely onto the ampoule receptacle. 
         [0030]    In some embodiments, e.g., in case a two-chamber ampoule is inserted into the ampoule receptacle instead of a one-chamber ampoule, the ampoule receptacle can comprise a cavity, which extends from the direction of the facing side along the ampoule receptacle, for the bypass of the two-chamber ampoule. A number of such cavities can be provided, distributed over the circumference, such that the ampoule can be inserted into the ampoule receptacle in almost any angular position. The cavity for the bypass can comprise rotational abutments which act in the circumferential direction and prevent a rotation of the ampoule relative to the ampoule receptacle when the ampoule is inserted. 
         [0031]    In some embodiments, at least one of the ampoule receptacle and the fastening member can comprise at least one projection, e.g. a cam, which is directed toward the seal. The at least one projection or cam can extend in the longitudinal direction of the ampoule or ampoule holder, e.g. in the distal direction or proximal direction. The seal, e.g. its facing side, abuts the at least one cam. The point-focussed abutment for the seal which is caused by the cam can reduce a clearance in the axial enclosure of the seal. The at least one projection can be arranged on the ampoule receptacle and/or fastening member rigidly or such that it is sprung, or biased or urged, in the axial direction. 
         [0032]    In some embodiments, the at least one projection, e.g. a cam, can be arranged on the ampoule receptacle, namely where the completely inserted product container enters into axial abutment, e.g. on the facing area of the ampoule receptacle. The at least one projection can alternatively or additionally be formed on a projection of the fastening member which is directed radially inwardly, e.g. where the fastening member clasps the facing side of the seal. 
         [0033]    In some embodiments, the ampoule holder, e.g. the ampoule receptacle and/or the fastening member, can comprise features or a structure which enable a needle unit to be fastened to the ampoule holder. The needle unit can be plugged on via a conical area or screwed on via a thread. When a needle unit is arranged on the ampoule, it can for be fastened to the ampoule holder via a fastening portion. When a needle unit is completely fastened, a piercing object, e.g. a sharp continuation or a needle, can penetrate the septum and establish a fluid connection between a distal needle tip of the needle unit and the product container. The needle unit is fixedly screwed to the fastening member via an inner thread with which an outer thread of the needle unit can engage. 
         [0034]    In some embodiments, the ampoule receptacle can comprise features or structure, e.g. a thread, using which it can be fastened to an injection device and, when fastened, moved into the injection device by an axial movement combined with a rotational movement. The ampoule receptacle can comprise one or more latching elements which generate an acoustic and/or tactile signal by latching over a counter element at selected positions when the ampoule holder is moved into the injection device. 
         [0035]    In some embodiments, due to the increased diameter of the septum, a thicker continuation or a thicker needle can be used for injecting into the septum, which with conventional narrow septa is only possible to a restricted extent, i.e. only possible using a thin needle. The thin needle, however, results in an increased delivery resistance. In some preferred embodiments, therefore, the needle unit may comprise a needle support from which a continuation projects in the proximal direction for penetrating the septum and from which an injection needle projects in the distal direction for injecting into a patient, wherein the continuation exhibits a larger diameter than the injection needle. A fluid channel which transports the product from the product container to the injection needle tip can be contained in the continuation and in the injection needle. The fluid channel can exhibit a larger fluid-guiding cross-section in the region of the continuation than in the region of the injection needle. 
         [0036]    In some embodiments, in the case of the ampoule holder in which the seal and/or its radial projection is arranged or can be arranged between the ampoule receptacle and the fastening member, the fastening member comprises the engaging member which acts on the product container or can be engaged with the product container. This can mean that a defined portion of the engaging member presses onto the product container. The engaging member can be arranged such that it is sprung or resiliently biased. The engaging member can thus press against the product container with a spring force when the fastening member is fastened to the ampoule receptacle and thus reduce or even eliminate the axial clearance of the product container between the ampoule receptacle and the fastening member. The sprung engaging member can alternatively or additionally be pressed against the seal of the product container by a part, e.g. the needle unit, which can be attached to the fastening member. This can also help reduce the clearances. 
         [0037]    In some embodiments, an arm may extend in the longitudinal direction or the circumferential direction for arranging the engaging member such that it is sprung or biased, wherein the engaging member is arranged on one end of the arm, and the other end of the arm is formed, e.g. integrally, on the fastening member. 
         [0038]    In some preferred embodiments, the fastening member, e.g. the engaging member, can comprise a latching element which at least hinders releasing the needle unit from the fastening member. Due to the latching element, a higher torque can be required for releasing the needle unit than without the latching element. It is thus possible to prevent the needle unit which is arranged on the fastening member from being unintentionally released. 
         [0039]    In some preferred embodiments of the ampoule holder, the fastening member can be attached to the ampoule receptacle by a plugging movement or rotational movement or a combination of the two. The fastening member can be connected or connectable to the ampoule receptacle via a thread, a longitudinal guide or a bayonet lock. The bayonet lock performs an axial movement when it is rotated, such that the axial clearance between the fastening member and the ampoule receptacle is reduced. The thread and the longitudinal guide likewise perform a longitudinal movement to reduce the clearance. 
         [0040]    In some preferred embodiments, one of the fastening member and the ampoule receptacle can comprise a latching means and the other of the fastening member and the ampoule receptacle can comprise a latching counter means, wherein the latching means and the latching counter means are in engagement or can be engaged when the fastening member is fastened. This connects the fastener to the ampoule receptacle such that it cannot be released. To reduce the axial clearance of the seal between the fastening member and the ampoule receptacle, the latching means and latching counter means can be configured such that when they mutually engage, the fastening member can be moved in discrete increments in the fastening direction and cannot be moved in the opposite direction. The fastening member, e.g. the engaging member, can be moved in discrete latching increments in the direction of the seal until the fastening member or the engaging member presses against the seal, such that the axial clearance of the seal is eliminated or at least reduced. 
         [0041]    In some embodiments, the latching means or latching counter means can be arranged such that they are biased or sprung, such that they can be urged engage. 
         [0042]    In some embodiments, the latching means can comprise at least one tooth or a number of teeth, and the latching counter means can comprise at least one tooth or a number of teeth, which are shaped such that the fastening member can be moved in one direction and cannot be moved in the other direction. Serrated latching teeth may be used. The latching teeth are arranged consecutively, lined up, in the fastening direction, in the circumferential direction or in the longitudinal direction. Arranging them consecutively or in a line achieves the discrete latching increments during fastening. It is in principle sufficient if one of the latching means and the latching counter means comprises one tooth and/or a single tooth, and the other of the latching means and the latching counter means comprises a number of teeth, in accordance with the desired number of discrete latching increments. 
         [0043]    In one exemplary preferred embodiment, the ampoule receptacle comprises a groove, wherein one groove flank or two groove flanks which point toward each other respectively comprise a latching counter means. The fastening member comprises a latching means which is arranged such that it is biased or sprung and is pressed against the groove flank assigned to it, into the latching counter means. In some preferred embodiments, one latching means for each groove flank is arranged on the fastening member. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0044]      FIGS. 1-4  depict embodiments of components or parts of one embodiment of a needle unit in accordance with the present invention; 
           [0045]      FIGS. 5 and 6  depict embodiments of individual parts of embodiments of an ampoule holder and a needle unit; 
           [0046]      FIG. 7  depicts an embodiment of an assembled ampoule holder, together with an ampoule accommodated in it; 
           [0047]      FIG. 8  depicts the ampoule holder of  FIG. 7 , with a needle unit arranged on it and on the ampoule; 
           [0048]      FIG. 9  depicts a preferred embodiment of a fastening portion of a needle unit; 
           [0049]      FIG. 10  depicts an exemplary preferred embodiment of an administering device in accordance with the present invention; 
           [0050]      FIGS. 11   a - 11   d  are a number of views of an exemplary preferred embodiment of a fastening member in accordance with the present invention; 
           [0051]      FIG. 12  depicts a preferred embodiment of an ampoule holder comprising a needle unit and the fastening member if  FIGS. 11   a - 11   d;    
           [0052]      FIG. 13  includes a number of views of an embodiment of an ampoule receptacle in accordance with the present invention, comprising a fastening member; 
           [0053]      FIG. 14  includes a number of views of another embodiment of an ampoule receptacle and a fastening member; and 
           [0054]      FIG. 15  depicts another embodiment of an ampoule receptacle and a fastening member. 
       
    
    
     DETAILED DESCRIPTION 
       [0055]    With regard to fastening, mounting, attaching or connecting components of the present invention, unless specifically described as otherwise, conventional mechanical fasteners and methods may be used. Other appropriate fastening or attachment methods include adhesives, welding and soldering, the latter particularly with regard to the electrical system of the invention, if any. In embodiments with electrical features or components, suitable electrical components and circuitry, wires, wireless components, chips, boards, microprocessors, inputs, outputs, displays, control components, etc. may be used. Generally, unless otherwise indicated, the materials for making embodiments of the invention and/or components thereof may be selected from appropriate materials such as metal, metallic alloys, ceramics, plastics, etc. Unless otherwise indicated specifically or by context, positional terms (e.g., up, down, front, rear, distal, proximal, etc.) are descriptive not limiting. Same reference numbers are used to denote same parts or components. 
         [0056]    Referring to  FIGS. 1-4 , a device in accordance with the present invention comprises a needle unit having a number of elements or parts  6 ,  7 ,  8 ,  10  which form a fluid channel which may also be referred to as a fluid-guiding channel. More generally, the parts forming the fluid channel are: a continuation  2 , which may also be referred to as a piercing means; a needle support  1 , which may also be referred to as a cannula support; and an injection needle  3 , which may also be referred to as a cannula tube. 
         [0057]    The hollow, cylindrical injection needle  3  exhibits a constant outer diameter D 3  and a constant inner diameter. At its distal (or forward or front) end, there is a cutting tip which is asymmetrical in the section shown. The injection needle  3  serves for injecting into the skin of a patient and is fastened via its proximal (rear) end to the needle support  1 . The fastening shown here consists of a part of the injection needle being accommodated in a hollow-cylindrical bore  5 , the inner diameter of which approximately corresponds to the outer diameter of the needle  3 . The needle  3  could in principle be pressed or molded in the hollow cylindrical portion of the needle support  1 , for example when the needle support  1  is manufactured by injection molding. In some embodiments, the needle is adhered into or on the needle support  1 . To prevent stress peaks when transverse forces are exerted on the needle  3 , the portion  5  is connected to an expanding region, e.g. a region which expands in the shape of a trumpet, which extends as far as the distal end of the needle support  1 , as shown here. Alternatively or additionally, this region can also serve to accommodate adhesive for an adhesive connection between the needle support  1  and the needle  3 . The needle  3  may be fastened to the needle support  1  such that it cannot be released. In some embodiments, the needle  3  is made of a metal which is suitable for injection needles, and the needle support  1  is made of plastic. 
         [0058]    The needle support  1  comprises a portion  8  of the fluid channel which is connected to the proximal end of the injection needle  3 . The portion  8  can be hollow and cylindrical. In particular, the portion  8  exhibits approximately the same fluid-guiding cross-section, e.g. the same inner diameter, as the injection needle  3 . This configuration reduces the risk of turbulence or a turbulent flow when fluid transitions from the portion  8  into the portion  10  of the injection needle  3 . 
         [0059]    The needle support  1  also comprises a portion  7  of the fluid-guiding channel, which exhibits a larger fluid-guiding cross-section than the portions  8  and  10  of the fluid-guiding channel. The portion  7  tapers in the direction of the injection needle  3 , i.e. the fluid-guiding cross-section is reduced in the portion  7  in the direction of the needle  3 . The fluid-guiding cross-section can be reduced at a constant rate, i.e. a constant gradient, or—as shown here—at an increasing and/or decreasing gradient. In the direction of the injection needle  3 , the fluid-guiding cross-section is initially reduced at an increasing gradient. Subsequently, the fluid-guiding cross-section tapers at a decreasing gradient. In a longitudinal section, the portion  7  of the fluid channel can exhibit a concave and/or convex curve of the channel wall. In the direction of the injection needle  3 , the wall of the portion initially exhibits a concave curve and subsequently a convex curve. The transitions between the individual portions, for example the transition from concave to convex, can be embodied to be continuous or at least to have no sharp edges. The same applies to the transition of the portion  7  into the portion  8 . 
         [0060]    The needle support comprises a shaft, for example a cylindrical shaft, which extends in the distal direction and in which the needle  3  is arranged and fastened. 
         [0061]    The needle support  1  is connected via a join or connection  9  to the continuation  2 . The join or connection can be a force-fit, material-fit or positive-fit connection. The join or connection is fluid-proof. A suitable join or connection can be achieved by adhering, pressing, latching or fusing. 
         [0062]    The continuation  2  which is connected to the needle support  1  comprises a portion  6  of the fluid-guiding channel. The portion  6  expands in the direction of the injection needle  3 , for example in the shape of a funnel or cone. A measure of the expansion can be a conical angle of approximately 4°, to cite just one example. The conical angle can range from 1° to 45°. In some preferred embodiments, rather smaller conical angles may be preferred. 
         [0063]    In some preferred embodiments, the portion  6  opens into the portion  7  when the needle support  1  is connected to the continuation  2 . The portions  6  and  7  can respectively exhibit an identical fluid-guiding cross-section, e.g. an identical inner diameter, at the aperture. 
         [0064]    The portion  6  can exhibit a cross-sectional ratio of its maximum fluid-guiding cross-section to its minimum fluid-guiding cross-section of 4:1. Cross-sectional ratios of 2:1 to 10:1 have proven to be advantageous. The ratio can also be 2.5:1 or other suitable ratio. 
         [0065]    The fluid to be administered is supplied from the environment of the continuation  2  to the fluid channel via an opening  4 . Although one opening  4  would in principle be sufficient, two openings  4  are shown in the depicted example, which are arranged opposite each other and on the side of the fluid channel  6 . A part of the fluid channel  6  is thus arranged between the openings  4 . The openings  4  have the shape of an elongated hole which can be between 1 and 4 mm long, e.g. 3 mm, and can exhibit a width of the diameter of the part of the fluid channel  6  which is arranged between the openings. The overall cross-sectional area of the openings  4 , or one of them, can be larger than the minimum fluid-guiding cross-section of the portion  6 . The ratio of the overall cross-sectional area of the openings  4  and the minimum fluid-guiding cross-section of the portion  6  can be 7:1. The overall cross-sectional area of the openings  4  should be at least as large as the minimum fluid-guiding cross-section. The cross-sectional ratio can range from 2:1 to 10:1 and to other suitable ratios. 
         [0066]    The continuation  2  comprises a rotationally symmetrical tip which is embodied in this example as a cone and forms the distal end of the continuation  2 . The arrangement of the two openings  4  causes the fluid to be supplied laterally, i.e. transverse to the longitudinal axis, and subsequently transported in the fluid-guiding channel (which may be thought of as comprising elements or portions  6 ,  7 ,  8 ,  10 ) along the longitudinal axis in the direction of the needle  3 . 
         [0067]    The continuation  2  comprises a connecting portion  12  using which the unit consisting of the needle support  1 , the continuation  2  and the needle  3  can be connected, indirectly or directly as applicable, to a part of the injection device. Alternatively, the needle support  1  could comprise the portion  12 . 
         [0068]    In the region of the fluid channel portion  7 , the proximal end of the needle support  1  comprises a recess which is surrounded by an annular protrusion. In this example, the annular protrusion is concentric with the longitudinal axis of the needle unit  100 . The distal end of the continuation  2  exhibits a shape which approximately corresponds to a negative mold of the proximal facing side of the needle support  1 . The distal facing side of the continuation  2  comprises an annular groove into which the annular protrusion is arranged when the continuation  2  is joined together with the needle support  1 , and comprises a truncated conical protrusion which engages with the recess of the needle support  1  when the continuation  2  and the needle support  1  are joined together. This achieves join or connection  9  which is fluid-proof. The mutual engagement of the two facing sides increases the surface which can be used for a connection  9 . 
         [0069]    The injection needle  3  can be selected from needles having a wide range of diameters, wall thicknesses and lengths; for example, it is equally possible to provide a 23 gauge needle or a 31 gauge needle. The injectable length of the injection needle  3  can be selected for a subcutaneous or transcutaneous injection. 
         [0070]    A needle unit  100  is shown in  FIGS. 5 and 6 . The unit, comprising the needle support  1 , the continuation  2  and the injection needle  3 , is connected to a fastening portion  13  via the connecting portion  12 . The sleeve-shaped fastening portion  13  serves to be connected to a fastening member  20  and comprises a thread, e.g. an outer thread, for this purpose. The unit forming the fluid channel (which, again, may be thought of and/or referred to as comprising elements, parts or portions  6 ,  7 ,  8 ,  10 ) is connected, axially fixed, to the fastening portion  13 . Depending on its application, the unit  100  can be rotatable or non-rotatable relative to the fastening portion  13 . The unit further comprises a connecting protrusion  12   a  which engages with an annular groove  13   c  formed on the inner circumference of the fastening portion  13 . The fastening portion  13  is connected such that it is rotationally and axially fixed to a casing  14 . The fastening portion  13  and the casing  14  could in principle also be formed integrally, however forming them in a number of parts has advantages when manufacturing the needle unit  100 . The sleeve-shaped casing  14  surrounds both the fastening portion  13  and the continuation  2  and its tip on the circumferential side. The casing  14  extends in the proximal direction, at least as far as the tip or—as shown here—beyond the tip, such that the tip of the continuation  2  does not protrude beyond the proximal end of the casing  14 . The risk of unintentional piercing by the tip of the continuation  2  is reduced by the casing  14  protruding beyond the tip  2 . An annular gap is formed between the fastening portion  13  and the casing  14 . The casing  14 , the fastening portion  13  and the unit  100  are arranged concentrically with respect to each other. 
         [0071]    The distal end of the casing  14  comprises a facing area comprising an opening through which the injection needle  3  protrudes by a length. This length substantially corresponds to the injection depth of the injection needle  3 , since the distal end of the casing forms an abutment area for the patient&#39;s body. For reasons of space, the casing  14  can comprise a cavity for the needle support  1 . 
         [0072]    The needle unit  100  also comprises a packaging sleeve  15  which in the position shown in  FIGS. 5 and 6  is arranged concentrically over the outer circumference of the casing  14 . The packaging sleeve  15  is held by the casing  14 , e.g. in a frictional fit. The packaging sleeve  15  surrounds the casing  14  completely over its circumference and also over its length. In some preferred embodiments, the packaging sleeve  15  proximally protrudes at least slightly beyond the proximal end of the casing  14 . The opening which is formed at the proximal end of the packaging sleeve  15 , through which the casing  14  together with the unit  100  can be inserted or removed, can be sealed with a so-called peel film in the delivered state of the needle unit  100 , to keep the contents of the packaging sleeve  15  sterile or at least to protect them from contamination. The packaging sleeve  15  distally protrudes beyond the distal end of the needle  3 , where it is sealed on its facing side. In this respect, the packaging sleeve  15  forms a closed cup which comprises an opening at its proximal end. The outer circumference of the packaging sleeve  15  comprises a structure which better enables a user of the device to apply a torque to the packaging sleeve  15 , about the longitudinal axis. Since, when completely placed on the casing  14 , the packaging sleeve  15  is connected, such that it is rotationally fixed, to the casing  14  at least in a frictional fit, and alternatively or additionally in a positive fit, the casing  14  together with the fastening portion  13  is rotated along with the packaging sleeve  15  when a torque is applied to the packaging sleeve  15 . 
         [0073]    The needle unit  100  can be attached to an injection device  50  ( FIG. 10 ). Parts of the injection device, namely an ampoule receptacle  30  and a fastening member  20 , are shown separately together with an ampoule  40  in  FIGS. 5 and 6 , assembled in  FIG. 7  and assembled with a needle unit  100  attached in  FIG. 8 . 
         [0074]    The ampoule  40 , such as is shown for example in  FIGS. 5 and 6 , is a so-called two-chamber ampoule (which may also be referred to as a two-chamber carpoule), one characteristic of which is that a product to be administered is merged or mixed, directly before being administered, from two components which for storage are contained in two different chambers. The distal chamber, i.e. the chamber which is arranged between a seal (comprised of parts  41 ,  42 ,  43 ,  44 ) and a first plunger  45 , can, for example, be partially or completely filled with a solid such as a granular or powdery material. A second chamber is situated proximally with respect to the first plunger  45  and is arranged between the first plunger  45  and a second plunger  46 . A fluid constituent of the drug can be situated in this chamber. Both plungers  45 ,  46  abut a hollow-cylindrical casing portion  48  of the ampoule  40 , forming a seal, and can be shifted along the casing portion  48 . 
         [0075]    In the region of the casing portion, the ampoule  40  comprises a so-called bypass  47  which forms a camber outwardly. The bypass  47  is axially longer than the first plunger  45 . 
         [0076]    For mixing, a pressure is exerted in the distal direction on the second plunger  46  and transferred onto the first plunger  45  via the fluid product in the chamber between the plunger  45  and the plunger  46 . When the second plunger  46  is shifted in the distal direction, the first plunger  45  is thus also shifted, as far as the region of the bypass  47 . Due to the camber of the bypass  47 , it is possible—providing the plunger  45  is situated completely in the region of the bypass  47 —for the fluid product to flow past the plunger  45  and into the distal chamber and to mix with the product constituent situated therein. The user can assist mixing by shaking the device. The fluid product has been completely removed from the proximal chamber when the second plunger  46  abuts against the first plunger  45 . The mixture consisting of the two product constituents can form a homogeneous or a heterogeneous mixture. The heterogeneous mixture of a fluid constituent with particles of solid is generally referred to as a dispersion, specifically a suspension. The product to be administered can then be delivered via the fluid channel of the needle unit  100 , the openings  4  of which are situated within the ampoule, such as for example in the region  42 , by shifting the plungers  45  and  46  in the distal direction along the hollow-cylindrical casing portion  48 . 
         [0077]    The ampoule  40  comprises a seal (which, again, may be thought of and/or referred to as being comprised of elements  41 ,  42 ,  43 ,  44 ) which comprises a septum  41  which can be penetrated by the continuation  2 . Such septa can be made of rubber or natural rubber or another suitable synthetic material. 
         [0078]    The septum  41  comprises a disc-shaped portion and a hollow-cylindrical portion connected to it in the proximal direction. The hollow-cylindrical portion forms a cavity in its interior, in which the openings  4  of the completely attached needle unit  100  are positioned in some preferred embodiments. The outer side of the hollow-cylindrical portion of the septum  41  centers the septum  41  on the inner circumference of the ampoule  40 , e.g. at the distal end of the ampoule  40 . An annularly circumferential bulge is formed at the distal end of the ampoule  40  and protrudes radially outwardly and may be referred to generally as a projection. The bulge  43  protrudes radially beyond the outer circumference of the hollow-cylindrical portion  48  of the ampoule  40 . In other words, the ampoule  40  exhibits a larger outer diameter at the point of the bulge  43  than in the region of the hollow-cylindrical portion  48 . In this example, the outer diameter of the bulge  43  also forms the maximum outer diameter of the ampoule  40 . The bulge  43  is integrally connected to the hollow-cylindrical portion  48 . This part of the ampoule can be formed from plastic or glass. The disc-shaped part of the septum  41  exhibits approximately the same outer diameter as the bulge  43 . The septum  41  and the bulge  43  are held together by a remolded or deformable part  44  which can be produced from a metal sheet. This part may also be referred to as a cap. The remolded part  44  clasps the septum  41  and the bulge  43  over their circumference and both distally with respect to the septum  41  and proximally with respect to the bulge  43 . The remolded part  44  connects the bulge  43  and the septum  41  such that they are axially fixed, i.e. holds them together in a fluid seal. The distal facing side of the remolded part  44  comprises an opening which can be circular and through which the continuation  2  can be inserted through the septum  41  into the interior of the ampoule  40  which has already been mixed. 
         [0079]    Between the hollow-cylindrical part  48  and the bulge  43 , the ampoule  40  comprises a neck which is constricted relative to the outer diameter of the portion  48 , such that the remolded part  44  can be reformed even more completely, e.g. further inwardly, around the proximal end of the bulge  43 . The proximal end of the ampoule  40  is open, such that a plunger rod  52  ( FIG. 10 ) can be slid into the ampoule  40  and onto the second plunger  46 . 
         [0080]    The fastening member  20  can be fastened to the ampoule receptacle  30 . The fastening member  20  and the ampoule receptacle  30  may be thought of and/or referred to as the ampoule holder. The fastening member  20  is sleeve-shaped and connected, e.g. latched, to the ampoule receptacle  30  such that it is rotationally and axially fixed. The rotational fixation is achieved by the engagement between the cavity  23  and the cam  34 . The axially fixed arrangement of the fastening member  20  on the ampoule receptacle  30  is achieved by the cam  32  latching into the windows  22 . 
         [0081]    As can be seen from  FIGS. 5 and 6 , the ampoule  40  is inserted into the ampoule receptacle  30  via a distal opening of the sleeve-shaped ampoule receptacle  30 . The outer diameter of the seal is larger than the inner diameter of the ampoule receptacle  30 , such that the seal abuts the distal end of the ampoule receptacle  30 . As can be seen from  FIG. 7 , the seal of the ampoule  40  is axially enclosed between the ampoule receptacle  30  and the fastening member  20  and thus axially fixed. The enclosure can allow the ampoule  40  a small axial clearance. However, the enclosure may be such that the axial clearance is further reduced. To this end, the distal end of the ampoule receptacle  30  comprises at least one projection—in this case, four projections  35 —which extend in the distal direction and which the seal abuts. The at least one projection  35  can be arranged on the ampoule holder, e.g. on the ampoule receptacle, rigidly as shown here or such that it is loaded or biased. Arranging it loaded has the additional advantage that an axial clearance is virtually no longer present. The loading arrangement can be achieved by providing a slit, which extends in the circumferential direction, proximally with respect to the at least one projection  35 , such that the stay which is situated between the slit and the projection  35  can be sprung in the axial direction. 
         [0082]    The seal can be enclosed from the distal side by a collar formed on the inner circumference of the fastening member  20 . The collar can partially or completely encircle the circumference. A projection  28  which extends inwardly from the inner circumferential area is provided, either as an alternative to or in addition to the collar, and can serve as an enclosure for the seal. On its side pointing toward the seal, the projection  28  comprises a projection, e.g. a cam  27 , which presses against the distal facing area of the seal, against the remolded part  44 . A part of the seal, such as the remolded part  44 , can be elastically or plastically deformed by the point-focussed burden of the cam  27 , thus achieving a secure, low-clearance enclosure of the seal between the ampoule receptacle  30  and the fastening member  20 . The cam  27  can be arranged rigidly or such that it is urged in the longitudinal direction. 
         [0083]    As can be seen from  FIGS. 5 to 7 , the outer circumference of the ampoule receptacle  30  comprises an outer thread  33  via which the ampoule holder can be screwed into a casing  51  of the injection device  50  ( FIG. 10 ), wherein the casing  51  comprises a corresponding inner thread for the outer thread  33  of the ampoule holder. To make the intuitive handling of the device  50  easier for the user, at least one arrow can be arranged on the ampoule holder, e.g. on the circumference of the ampoule receptacle  30 , which points in the direction of rotation for mixing the device. In some preferred embodiments, a multitude of arrows are distributed over the length of the ampoule receptacle  30 . The arrows can be printed on or formed as elevations or recesses which are molded as the ampoule receptacle  30  is injection-molded. The at least one arrow can be arranged between adjacent flights of the thread  33 . 
         [0084]    The ampoule holder, e.g. the ampoule receptacle  30 , also comprises a latching member  36  which is mounted such that it is biased in the radial direction. The springiness or resiliency is generated by an arm which extends in the circumferential direction and which is formed on the ampoule receptacle  30  and on which the latching member or cam  36  is formed. The function of said latching member  36  is described below with reference to  FIG. 10 . 
         [0085]    The fastening member  20  also comprises a single-flight or multiple-flight thread—in this example, in the form of two threaded portions  21  which enable the needle unit  100 , comprising the outer thread situated on the fastening portion  13 , to be screwed onto the injection device. Due to the axial movement of the continuation  2  when the needle unit  100  is screwed on, the tip of the continuation  2  penetrates the septum  41 . The torque required for screwing on the needle unit  100  is applied via the packaging sleeve  15  or the casing  14 . Once the needle unit  100  has been completely screwed on, it assumes the position shown in  FIG. 8 . The openings in this case are then situated within the ampoule  40 , such that the distal end of the injection needle  3  is fluidically connected to the interior of the ampoule  40 . A distal portion of the fastening member  20  is then situated in the annular gap between the fastening portion  13  and the casing  14 . 
         [0086]    Providing the unit  100  is arranged such that it can be rotated relative to the fastening portion  13 , it is possible for the continuation to inject into the septum  41  with a purely axial movement. This can offer advantages with regard to the seal between the septum and the continuation. If the unit is arranged such that it is rotationally fixed relative to the fastening portion  13 , the septum is penetrated by the continuation  2  by means of a combined rotational and axial movement, which offers advantages with regard to the torque required for screwing on the needle unit  100 . 
         [0087]    As can be seen from  FIGS. 5 and 9 , the fastening member  20  comprises an abutment  26  which acts in the circumferential direction, and the fastening portion  13  comprises an abutment  13   a  which likewise acts in the circumferential direction. A number of such abutments—such as two such abutments in this example—can also be arranged on each of the fastening member  20  and the fastening portion  13 . 
         [0088]    The abutments  26  and  13   a  form an abutting pair and are positioned such that they pass into a rotational abutment when the needle unit  100  is in its completely screwed-on position ( FIG. 8 ), thus securely preventing any further rotation. The abutment  13   a  is formed on the proximal end of the fastening portion  13 . The abutment  26  is formed on the projection  28  of the fastening member  20 . An axial abutment could also optionally be provided instead of a rotational abutment, however the rotational abutment has the advantage over an axial abutment that the parts which pass into abutment are not burdened as much, since due to the translation generated by the thread pitch, a significantly greater force can be achieved by a particular torque in the axial direction than in the circumferential direction. 
         [0089]    The fastening member  20  can comprise one or more projections  24  or  25  which latch to the needle unit  100  shortly before the rotational abutment is reached, such that a reverse rotation of the needle unit  100  in the opposite direction is only possible using an increased torque or is not at all possible, i.e. is only possible by destroying a component or a part of a component. Alternatively, cavities which serve the same purpose can be provided instead of the projections  24 ,  25 . Due to the latching when the needle unit  100  is screwed on, the user obtains on the one hand a tactile signal which indicates to him/her that the needle unit  100  has then been completely screwed on. On the other hand, it prevents an unintentional reverse rotation, such that the risk of misapplication can be reduced. Where cavities or cams  24  are provided as the reverse rotation block, these engage with the casing  14  of the needle unit  100 , with its facing side formed in the annular gap. For this purpose, the facing side can comprise at least one projection—such as for example ribs or a cam—or a cavity, which is traversed shortly before or when the rotational abutment is reached. 
         [0090]    A projection  25  can alternatively or additionally be provided in the form of a cam which protrudes in the distal direction and traverses a projection  13   b , e.g. a cam, shortly before or when the rotational abutment is reached. The projection  13   b  is arranged on the proximal facing side of the fastening portion  13  and, offset in the circumferential direction, in front of the abutment  13   a . The distance between the projection  13   b  and the abutment  13   a  can correspond approximately to the width of the projection  25  as measured in the circumferential direction, which means that the cam  25  is held between the abutment  13   a  and the projection  13   b  when the needle unit  100  is completely screwed on. 
         [0091]    A projection  13   b  which allows a screwing movement counter to the screwing-on direction can comprise flanks which are flattened on both sides in the circumferential direction. A projection  13   b  which is intended to prevent a rotation counter to the screwing-on direction from being possible can exhibit the shape of a serrated tooth which allows the projection  13   b  to be traversed but prevents a reverse rotation due to the steep area of the serrated tooth. The same applies of course to the latching between the cavities or projections  24  and the cavities or projections on the casing  14 . 
         [0092]    The projection  13   b  is arranged on the facing side of the fastening portion which is embodied as a helical rail. The helical shape exhibits approximately the pitch of the thread of the fastening portion  13 . 
         [0093]    A preferred embodiment of an injection device in accordance with the present invention is shown in  FIG. 10 . The device is a mixing and delivering device  50  which for the sake of simplicity is referred to in the following as an injection device. The injection device  50  comprises a casing  51  comprising an inner thread into which the ampoule holder shown in  FIG. 7 , which comprises an outer thread  33 , can be screwed. A plunger rod  52  is arranged within the sleeve-shaped casing  51  and is connected to an injection button  58 . When the injection device  50  is in its initial state, i.e. before the product constituents of the two-chamber ampoule  40  have been mixed, the injection button  58  is surrounded over its axial length, e.g. completely, by the casing  51 . Two wings  57  which point radially outwardly are arranged on the casing  51 . The small plate-shaped wings make it easier for the user to hold the device and apply a necessary torque when mixing. The wings  57  thus serve as a gripping aid and, in combination with a gripping portion  29 , improve the intuitively correct handling. The wings  57  are situated at the proximal (rear) end of the device  50 . 
         [0094]    In one preferred embodiment, the injection device comprises an outer sleeve  29  which serves as a gripping portion and which the user of the device  50  can clasp in one hand, while he or she screws the casing  51  onto the ampoule holder, into the annular gap formed between the outer sleeve  29  and the ampoule receptacle  30 , with the other hand at the wings  57 . This has the advantage that it allows patients who have restricted motor abilities to securely mix the product constituents. At the end of the mixing sequence and as applicable a priming sequence, the abutment  29   a  formed at the proximal end of the outer sleeve  29  and the abutment  54   a  formed by the casing  51  in the region of the distal end pass into a rotational or axial abutment, such that this indicates to the user that the mixing process and priming process are complete. 
         [0095]    In an alternative, also preferred embodiment, the injection device  50  is without the outer sleeve  29 . The user of the injection device can clasp the packaging sleeve  15  or the casing  14  with one hand and the casing  51  or as applicable wings  57  fastened to it with the other hand, to apply the torque. Mixing is analogous relative to the embodiment comprising a sleeve-shaped gripping portion  29 , wherein the end of the mixing process is indicated by the rotational or axial abutment of the distal end of the casing  51  against the annularly circumferential collar of the ampoule holder which is indicated in  FIG. 5  by the reference sign  31 . This variant is also possible, in the embodiment comprising an outer sleeve  29 . Due to the rotational abutments  26 ,  13   a  between the needle unit  100  and the ampoule holder, it is possible to securely prevent the components involved in the abutment from being overloaded, even when the torque for mixing passes via the needle unit  100 . 
         [0096]    In both exemplary embodiments of an injection device  50 , it is the case that when the ampoule receptacle  30  and the casing  51  are screwed into each other when mixing the product constituents, the plunger rod  52  passes into abutment with the plunger  46 , thus moving the casing  51  in the distal direction relative to the plunger rod  52 , wherein the plunger rod  52  remains axially fixed relative to the ampoule  40  due to the static friction between the plunger/plungers  45 ,  46  and the ampoule wall. The plunger rod  52  comprises a cavity, on the distal end  53  of which an abutment  53  is formed. While the ampoule receptacle  30  is being screwed into the casing  51 , the axial abutment  56  which is formed by the casing  51  is moved in the direction of the abutment  53 . The injection button  58  protrudes proximally out of the casing  51  during this movement. As soon as the abutment  56  abuts against the abutment  53 , the plunger rod  52  is slaved such that the plunger rod  52  participates in the axial movement of the casing  51  in the distal direction relative to the ampoule receptacle  30  and relative to the ampoule  40 . The plunger rod  52  can then shift the plunger  46  in the distal direction, thus performing the mixing sequence such as has been described further above. At the end of mixing, the latching member  36  can engage with or traverse a latching element  54 , which can indicate the end of the mixing process to the user. The user then shakes the device  50 , such that the product constituents are mixed. The user can subsequently prime the device to remove from the ampoule  40  any air which may still be contained in the ampoule  40 . For this purpose, the user can continue the screwing movement of the casing  51  relative to the ampoule receptacle  30 , wherein both plungers are then shifted and the volume in the product container is reduced, thus expelling the air from the product container  40  via the fluid channel of the needle unit  100 . At the end of the priming sequence, the latching member  36  can latch into another latching element  55 , likewise formed on the inner circumference of the casing  51 , thus indicating the end of the priming sequence to the user. The device  50  is then ready for a product delivery which, after the needle  3  has been injected into a desired point on the body, is initiated by pressing the injection button  58  in the distal direction relative to the casing  51  and relative to the ampoule  40 . 
         [0097]    The latching elements  54  and  55  can be formed such that an acoustic or tactile signal is generated during an interaction, e.g. when the latching member  36  traverses the latching elements  54  and  55 . By forming the flanks on the latching member  36  to be asymmetrical in the circumferential direction, it is also possible that once the latching member  36  has reached the latching elements  54  or  55 , any further rotation in a direction counter to the mixing or priming movement is no longer possible. 
         [0098]    In the embodiment comprising an outer sleeve  29 , the latter can be connected to the ampoule receptacle  30  such that it is rotationally and axially fixed, for example by a latching connection or by forming it integrally with the ampoule receptacle  30  or the fastening member  20 . The outer sleeve  29  can extend from the fastening member  20  far enough in the proximal direction that its proximal end proximally protrudes beyond the proximal end of the ampoule  40  and also beyond the proximal end of the product container receptacle  30 . 
         [0099]    The embodiment shown in  FIG. 10  has the advantage that the user of the device  50  does not see any thread, which may be advantageous in the case of people who regard technology with skepticism. A color coding may be given on the outer side of the casing  51 , from which it is additionally possible to optically tell whether the device is being mixed or primed or whether the device is ready for a product delivery. A first color can be arranged such that it is covered by the first sleeve  29  after mixing is complete. A second, different color can also be provided which disappears beneath the second sleeve  29  after priming. A third color can then be provided which indicates to the user that the device is then ready for a product delivery. To improve the grip, the outer sleeve  29  can be provided with a friction-increasing structure, for example ribs or pimples, or a friction-increasing material such as a rubber layer. The same also applies to the wings  57 . 
         [0100]      FIGS. 11   a  and  11   d  show a preferred embodiment of a fastening member  20 . In  FIG. 12 , the fastening member  20  shown in  FIGS. 11   a  to  11   d  is fastened to or carried by the ampoule receptacle  30 , wherein the needle unit  100  is arranged on the fastening member  20 . 
         [0101]    The fastening member  20  can be connected to the ampoule receptacle  30  using one of the options described here, which are exemplary of suitable options. The fastening member  20  comprises a thread  21  which is an example of a way of fastening the needle unit  100  to the fastening member  20 . Alternatively, ways of fastening the needle unit  100  which are described here or which are known from the prior art can be provided. The fastening member  20  comprises at least one—in this case, four—engaging members  20   a  which are each arranged on an arm such that they are sprung, or urged or biased. The arm extends in the circumferential direction, is connected at one end—e.g. integrally—to the fastening member  20 , and comprises the engaging member  20   a  at its other end, i.e. its free end. As can best be seen from  FIG. 12 , the engaging member  20   a  is pressed against the distal (forward) end of the product container  40 , i.e. against the seal (which again, may be thought of and/or referred to as made up of elements  41 ,  43 ,  44 ), when the needle unit  100  is fastened to the fastening member  20 . For this purpose, the needle unit  100  comprises an area which points in the proximal direction and presses against the engaging member  20   a . At the latest after or when the needle unit  100  is attached to the ampoule holder the seal of the product container  40  is enclosed, with no clearance, between the ampoule receptacle  30  and the fastening member  20 , e.g. the engaging member  20   a . The seal of the product container  40  can have a slight axial clearance before the needle unit  100  is attached. Even before the needle unit  100  is attached, this axial clearance can be reduced or even eliminated by the engaging member  20   a  pressing against the seal in such a way that it is sprung. The attached needle unit  100  holds the engaging member  20   a  in abutment with the distal facing side of the seal. 
         [0102]    The fastening member  20 , e.g. the engaging member  20   a , can comprise a projection  20   b  which protrudes distally beyond the facing side of the fastening member  20 . This enables the engaging member  20   a  to press against the seal of the product container  40 . The projection  20   b  can solely or additionally have the effect of the projections  24  or  25  shown for example in  FIGS. 5 and 6 , to which reference is hereby made. The needle unit  100  can of course comprise the corresponding elements such as are described for the co-operation with the projections  24  or  25 . 
         [0103]      FIGS. 13 and 14  show embodiments in which the fastening member  20  is plugged onto the ampoule receptacle  30  by an axial movement, without a rotational movement, and latched to the ampoule receptacle  30 . The latching device is formed such that the fastening member  20  which is latched to the ampoule receptacle  30  can be shifted in the fastening direction or plugging direction and cannot be shifted in the opposite direction. Thus, once it is latched to the ampoule receptacle  30 , the fastening member  20  can no longer be removed from the ampoule receptacle  30  but can be slid on further, wherein the fastening member  20  latches further in the plugging direction in discrete increments. The axial clearance which the seal of the product container  40  has between the ampoule receptacle  30  and the fastening member  20  can be reduced with each latching increment, until a latching position is eventually reached in which the fastening member  20  presses against the seal of the product container  40 . This encloses the seal with no axial clearance. 
         [0104]    In some embodiments, the fastening member  20  comprises a latch structure or latching means  20   c  as its latching device and the ampoule receptacle  30  comprises a complementary latch member or latching counter means  30   c  as its latching device, wherein the latching means  20   c  and the latching counter means  30   c  mutually engage for the latching connection. In the example shown in  FIG. 13 , the latching counter means  30   c  is arranged on an arm, such that it is sprung or urged, while the latching means  20   c  is arranged approximately rigidly on the fastening member  20 . In the example shown in  FIG. 14 , the latching means  20   c  is arranged on an arm, such that it is sprung, and the latching counter means  30   c  is arranged substantially rigidly on the ampoule receptacle  30 . 
         [0105]    The latching means  20   c  and latching counter means  30   c  comprise a number of serrated teeth or other suitable structures which are arranged in succession in the axial direction and are complementary and/or mutually engageable. It is in principle sufficient if one of the latching means  20   c  and the latching counter means  30   c  comprises one tooth and the other of the latching means  20   c  and the latching counter means  30   c  comprises a number of teeth, wherein for increased stability, the latching means  20   c  and the latching counter means  30   c  each comprise a number of mutually engaging teeth. The distal region of the ampoule receptacle  30  shown in  FIG. 13  comprises centering areas and the arm comprising the latching counter means  30   c , wherein the centring areas radially center the fastening member  20 . The latching counter means  30   c  is arranged on the outer side, e.g. protruding radially outwardly, on the ampoule receptacle  30 . 
         [0106]    The ampoule receptacle  30  shown in  FIG. 14  comprises a groove  30   a  which, extends in the longitudinal direction and is laterally enclosed by groove flanks  30   b . The groove flanks  30   b  each comprise a latching counter means  30   c , wherein the latching counter means  30   c  is directed from one groove flank  30   b  toward the other groove flank  30   b . The fastening member  20  comprises two latching means  20   c , each arranged on an arm, which can be sprung or urged toward and away from each other. The ampoule receptacle  30  comprises a centering area which radially centers the fastening member  20  as it is plugged on. As the fastening member  20  is plugged on, the latching means  20   c  and latching counter means  30   c  pass into engagement, wherein the latching means  20   c  are pressed toward each other by the groove flanks  30   b , wherein the sprung or resilient arrangement presses the latching means  20   c  into engagement with the latching counter means  30   c . This achieves a stable fastening. The arms which bear the latching means  20   c  could in principle extend in the proximal direction from the fastening member  20 , wherein the latching means  20   c  is arranged on the proximal end of the arm. Another arrangement is shown in  FIG. 14 , wherein the sprung arms are formed at the proximal end of an arm which extends in the proximal direction from the fastening member  20 . The sprung arms extend in the distal direction from the proximal end of one arm, wherein the latching means  20   c  is arranged on the distal end of the sprung arm. 
         [0107]      FIG. 15  shows another preferred exemplary way of fastening the fastening member  20  to the ampoule receptacle  30 . As opposed to the embodiments from  FIGS. 13 and 14 , the fastening is based on a plug-rotation connection instead of a purely axial plug connection. This plug-rotation connection is generally also referred to as a bayonet lock (comprising elements  20   f ,  30   f ). For the bayonet lock, the inner circumference of the fastening member  20  comprises a groove-shaped guiding track  20   f  into which a cam  30   f  of the ampoule receptacle  30  which protrudes radially outwardly can be inserted. The fastening member  20  is fastened by rotating it relative to the ampoule receptacle  30 . The fastening member  20  also performs a longitudinal movement as it is rotated, such that the seal of the product container  40  (not shown) is enclosed, with no clearance, between the ampoule receptacle  30  and the fastening member  20 . To prevent the fastening member  20  from being released from the ampoule receptacle  30 , the ampoule receptacle  30  comprises a latching counter means  30   c  which is formed, such that it is resilient, on an arm which extends in the circumferential direction, wherein the latching counter means  30   c  can engage with the latching means  20   c  which is formed on the inner circumference of the fastening member  20 . As in the embodiments of  FIGS. 13 and 14 , the latching means  20   c  and the latching counter means  30   c  comprise serrated teeth, wherein the teeth are likewise arranged successively in a line in the fastening direction. Since the fastening direction is a rotational movement in the embodiment from  FIG. 15 , the teeth are lined up and/or arranged successively in a line in the circumferential direction. Alternatively, of course, a threaded or other suitable coupling arrangement can be provided for the fastening instead of a bayonet lock. 
         [0108]    Embodiments of the present invention, including preferred embodiments, have been presented for the purpose of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms and steps disclosed. The embodiments were chosen and described to illustrate the principles of the invention and the practical application thereof, and to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth they are fairly, legally, and equitably entitled.