Medical syringe and needle attachment for such a syringe

Abstract

In a medical syringe (1) comprising a syringe body (2) having an active substance container, wherein the active substance container is sealingly closed by means of a pierceable membrane (28) arranged in the syringe body (2), in the region of the distal end (4) of the latter, and comprising a needle attachment (6) which can be mounted on the syringe body (2) and which carries a needle system formed by an injection needle (42) and by a septum needle (44) connected to the latter at the fluid side, the aim is to ensure in a particularly simple manner, and thus also in a manner suitable for use in large batch numbers, that the septum needle (44) is kept reliably spaced apart from the septum (28) during transport, storage or other handling, such that the septum cannot be accidentally damaged by the septum needle (44), which could result in the active substance being contaminated or active substance being lost. To this end, according to the invention, the needle attachment (6) can be mounted on the syringe body (2) by means of a screw connection.

Description

[0001] Description

[0002] Medical syringe and needle attachment for such a syringe

[0003] The invention relates to a medical syringe with a syringe body having an active ingredient container, the active ingredient container being sealed by a pierceable membrane arranged in the region of the distal end of the syringe body. The invention also relates to a needle attachment attachable to the syringe body, which carries a needle system formed by an injection needle and a septum needle connected to the injection needle on the fluid side. It further relates to a needle attachment for such a medical syringe.

[0004] Such syringes are commonly referred to as "dry needle systems." They are used to provide syringes prefilled with an active ingredient in a largely preassembled system. For reasons of storage stability and to protect the active ingredient from contamination during storage and handling, the syringe needle is kept separate from the active ingredient and, in particular, should not come into contact with it. A so-called "dry" syringe needle exists when the syringe needle is not wetted by the active ingredient or otherwise comes into contact with it during storage or other handling. To make this possible, the active ingredient reservoir in such a syringe is usually sealed with a pierceable membrane.This membrane, also known as the "septum," is pierced by a dedicated septum needle to administer the active ingredient. This needle, in turn, is fluidically connected to the actual injection needle and thus establishes the fluid connection between the injection needle and the active ingredient reservoir. Prefilled syringes made of glass or plastic are generally supplied for use and administration of the drug formulation already contained in the syringe and ready for use. They are generally filled with an air space or gas bubble because they are filled from the open end opposite the needle end and then sealed. Gas bubbles can cause the stopper to move and sterility to be lost during transport due to pressure fluctuations. In addition, the drug can move through the headspace and dislodge the silicone oil from the surface.Silicone oil droplets can also interact with drug molecules, especially with biological agents. Prefilled syringes can be filled bubble-free using vacuum closures. However, this is generally limited to low-viscosity formulations and significantly slows down the filling line, resulting in additional costs.

[0005] If possible, the filled syringes containing the medication should be gas-sterilized. Prefilled syringes with a pierced needle, whether made of glass or plastic, generally cannot be terminally sterilized because the needle guard that seals the needle tip is made of permeable rubber compounds to allow the needle to be gas-sterilized before filling during production. Final sterilization by gas would degrade the medication. While prefilled Luer-Lock syringes can be terminally sterilized, the user must remove the syringe from the sterile packaging before attaching the needle, which can lead to a loss of sterility.

[0006] Terminal sterilization of a prefilled syringe is a major advantage in most cases, as it significantly reduces the risk of cross-contamination and loss of sterility. For example, Luer-lock syringes are used in ophthalmology, where terminal sterilization is preferred. However, the user must still attach the needle after removing the syringe from the sterile protective blister, leading to potential user error and the risk of loss of sterility. An alternative to prefilled syringes are cartridge-based syringes or pens. The cartridge consists of a glass or plastic barrel, a pierceable septum held at one end by a crimped metal sleeve, and a plug / plunger at the other end.Typically, an injection needle is manually attached by the user before use by screwing a double-ended needle onto a cartridge holder or other device, such as a pin, that holds the cartridge. This perforates or pierces the membrane and creates a fluid pathway between the cartridge's drug contents and the injection needle. Such arrangements are typically used in pen injectors such as insulin pens and dental cartridge systems. Because the user must attach the needle, there is a risk of operator error and loss of sterility.

[0007] With the aforementioned dry or double-needle systems for prefilled syringes, it is crucial that the septum needle reliably pierces the membrane when the syringe is prepared for the application of the active ingredient, so that the fluid-side connection between the active ingredient reservoir and the injection needle required for administering the active ingredient can be established. On the other hand, it must be ensured that the septum needle is reliably kept at a distance from the septum during transport, storage, or other handling, so that the septum needle cannot be inadvertently damaged, which could lead to contamination of the active ingredient or loss of active ingredient.

[0008] The invention is therefore based on the object of providing a medical syringe of the aforementioned type with which the aforementioned requirements can be met reliably, but also in a particularly simple manner, and thus also suitable for use in large quantities. Furthermore, a particularly suitable needle attachment for such a medical syringe is to be provided. With regard to the medical syringe, this object is achieved according to the invention in that the needle attachment can be attached to the syringe body by means of a screw connection.

[0009] The invention is based on the consideration that, in order to particularly reliably comply with the aforementioned requirements, a reliable and very precisely adjustable guide for the septum needle in relation to the pierceable membrane should be provided. According to one aspect of the invention, this is achieved by translating a rotary movement into a feed movement by means of a threaded connection, with which, depending on the selection and design of the thread parameters, a very stable, mechanically well-guided, and very finely metered advance of the septum needle towards the membrane can be generated. Such a threaded drive can also be designed to be self-locking, so that when not yet inactive, i.e. during storage or other handling, the septum needle can be reliably positioned at a distance from the membrane.On this basis, a screw connection is provided for the syringe to attach the needle attachment to the syringe body, by means of which the septum needle can be positioned and moved with particular precision.

[0010] Advantageous embodiments of the invention are the subject of the subclaims.

[0011] Advantageously and according to one aspect of the invention, screwing the needle attachment into the syringe body causes the septum needle to be propelled in the direction of the pierceable membrane, wherein the properties of this propulsion can be adjusted particularly precisely by means of the thread parameters of the screw connection, in particular the pitch of the thread.

[0012] In a further advantageous embodiment, the screw connection is designed as a Luer connection. This takes particular account of the fact that Luer connections are generally widespread in the field of such applications, so that existing components could be used in the sense of a platform concept and the interchangeability and compatibility of different components with one another. With regard to the choice of parameters, according to a preferred aspect of the invention, the components are dimensioned such that the septum needle pierces the membrane arranged in the syringe body when the screw connection is fully established. This means that when the components of the screw connection are fully screwed into one another and accordingly move to the end stop, the septum needle reliably establishes the fluid-side connection to the interior of the active ingredient reservoir.

[0013] In an advantageous embodiment of the invention, the intended screw connection is formed by an external thread arranged on a base body of the needle attachment in combination with an internal thread of a connecting piece of the syringe body adapted to this.

[0014] In a particularly advantageous and independently inventive aspect of the invention, the screw connection is also designed to securely position and fix the septum needle at a sufficient distance from the membrane during storage or transport, so that unwanted piercing of the membrane or even damage to it by the septum needle is reliably ruled out. For this purpose, according to one aspect of the invention, the screw connection can be equipped with a removable intermediate stop which, during storage or transport, only allows partial screwing in of the components and thus only partial advancement of the septum needle towards the membrane. This movement is limited by the intermediate stop according to one aspect of the invention so early that the septum needle reliably does not reach the membrane and is fixed in position at a sufficient distance from it.Only after removing this intermediate stop should the septum needle be able to advance completely, allowing it to reach the membrane and ultimately pierce it.

[0015] To make this possible and to provide it in a particularly simple manner and suitable for mass production, according to one aspect of the invention the needle attachment comprises a needle protection cap which partially surrounds the external thread by means of a cover skirt formed on the end. The cover skirt is preferably arranged and dimensioned such that when its end edge rests against the front surface of the connecting piece, the septum needle is still spaced apart from the membrane in the syringe body. As long as the needle protection cap is then on the needle attachment, further screwing in of the components is not possible due to the stop thus formed and is thus excluded; accidental or unintentional damage to or puncture of the membrane by the septum needle is thus ruled out.

[0016] With regard to the needle attachment, in particular intended for use with the syringe body of a medical syringe of the type mentioned, the said object is achieved with a base body which carries a needle system formed by an injection needle and a septum needle connected to the latter on the fluid side, and which is provided on the outside with an external thread, and with a needle protection cap which partially surrounds the external thread by means of a covering apron formed on the end.

[0017] An embodiment of the invention is explained in more detail with reference to a drawing. In the drawing:

[0018] FIG. 1 The components of a medical syringe prefilled with an active ingredient in longitudinal section in exploded view,

[0019] FIG. 2 shows the tip body of the syringe according to FIG. 1 in an enlarged longitudinal section,

[0020] FIG. 3 shows the needle attachment of the syringe according to FIG. 1 in perspective view,

[0021] FIG. 4 shows the needle attachment according to FIG. 3 in an enlarged longitudinal section,

[0022] FIG. 5 shows the syringe assembled from the components according to FIG. 1 in longitudinal section in the storable state, FIG. 6 shows a partial enlargement of FIG. 5,

[0023] FIG. 7 shows the syringe according to FIG. 5 after removal of the needle cap and before preparation for use in longitudinal section, and

[0024] FIG. 8 shows the syringe according to FIG. 5 with the needle attachment fully screwed on in longitudinal section.

[0025] Identical parts are provided with the same reference numerals in all figures.

[0026] The medical syringe 1 according to FIG. 1 essentially comprises three assemblies or components, namely an active ingredient container (also referred to as a cartridge unit) forming the syringe body 2, which is provided at its distal end 4 for connection to a needle attachment 6 or needle holder, and at its proximal end 8 for connection to an actuating element 10. The syringe body 2 is designed, in accordance with a conventional design, as a cylindrical or tubular hollow body 12, which in the exemplary embodiment is intended directly to receive the medical active ingredient and thus as an active ingredient container. Alternatively, the active ingredient container could also be designed as a separate component in the manner of a so-called cartridge or ampoule, which can be inserted or inserted into the actual syringe housing.

[0027] The syringe 1 is designed as a prefilled medical syringe that is filled with the active ingredient in a central filling process by the manufacturer and can then be transported and / or stored with the active ingredient contained therein before being prepared for the actual application, i.e., the injection of the contained active ingredient. In order to meet the corresponding requirements for safe storage and handling, possibly even over an extended period of time, the hollow body 12 forming the active ingredient container is suitably sealed and sealed. This is intended to prevent undesired loss of the active ingredient, particularly during transport or storage, as well as to prevent and, if possible, completely eliminate any possible ingress of impurities or contamination into the stored active ingredient.

[0028] According to one aspect of the invention, the syringe body 12 is designed for connection to the needle attachment 6 by means of a screw connection, in an independently inventive embodiment, in particular by means of a Luer connection. For this purpose, the hollow body 12, as can be clearly seen in particular from the enlarged longitudinal section in FIG. 2, is provided at its distal end 4 with a connecting piece 14 for the needle holder 6, which is provided on the inside with an internal Luer thread 16. The connecting piece 14 surrounds in its interior a connecting pin 20 which is arranged centrally, leaving a circumferential threaded space 18 free, and which in turn has a connecting channel 22 in the center which tapers continuously, in particular conically, towards the distal end 4.

[0029] To enable the aforementioned reliably sealed design of the active ingredient container, the hollow body 12 is provided at its distal end 4 in the region of the connecting piece 14 with an integrated closure body 24 that can be pierced by the syringe needle arranged in the needle holder 6. The closure body 24 is designed as a three-dimensional molded body. According to an aspect considered to be independently inventive, this forms a comparatively thin, pierceable membrane 28, also referred to as a "septum," in a proximal central region 26 facing the interior of the hollow body 12. A funnel-shaped fixing skirt 30 is molded around the membrane 28, the outer contour of which is adapted to the inner contour of the connecting channel 22.The closure body 24 can thus be inserted into the connecting channel 22 from the proximal end 8 of the hollow body 12 and, due to its shape tapering towards the distal end 4, is fixed there in the longitudinal direction towards the distal end 4. After the hollow body 12 has been filled with active ingredient, it is in contact with the septum 28 from the proximal side of the closure body 24, so that in this state, displacement of the closure body 24 in the proximal direction is no longer possible; the closure body 24 is thus fixed in the longitudinal direction in the connecting channel 22. Of course, shape-related adhesive forces on the wall or adhesive forces caused by deformation can also effect or reinforce this fixation, so that the closure body 24 is securely fixed in the connecting channel 22.

[0030] With regard to the material selection for the syringe housing or the hollow body 12 forming it, which is considered inventive in itself, particular account is taken of the high demands placed on the reliable temporary storage of the medicinal agent, coupled with particularly high safety in handling the components. The syringe body 12, designed as a cylindrical hollow body, can be made of COC, PC, or PP, but in the illustrated embodiment, in a design considered inventive, is made of the high-performance plastic cycloolefin polymer (COP). This material is characterized by high fracture strength and glass-like transparency. Furthermore, it does not release alkali ions, thus eliminating the risk of a pH shift in the stored active agent.The closure body 24, on the other hand, is made of the comparatively soft TPE, so that the intended piercing of the syringe needle is also possible without any problems while maintaining a high level of tightness.

[0031] In an embodiment also considered to be independently inventive, a two-component injection molding process is provided for the production of the hollow body 12 provided with the closure body 24. The components are manufactured together in a single process, so that the intended displacement-proof positioning of the closure body 24 in the hollow body 12 can be achieved easily and simply. The syringe body 12 is preferably manufactured by injection molding, with, among other things, the shaping being carried out in such a way that possible dead volumes in the interior are kept particularly small.

[0032] Corresponding to the closure body 24, a movable plug 32 is provided within the hollow body 12 for securely and sealingly closing the proximal end 8. This plug is dimensioned such that it forms a sealing contact with the inner wall of the hollow body 12; the reservoir for the active ingredient, in which the active ingredient can be stored, is thus formed in the longitudinal region of the interior of the hollow body 12 between the septum 28 and the plug 32. In a conventional design, the plug 32 is movable within the hollow body 12 via the actuating element 10 arranged at the proximal end 8 of the syringe body 12, for example, an actuating plunger or an element with an automated drive.

[0033] In order to meet the highest demands regarding sealing on the one hand and sliding properties within the hollow body 12, for example with regard to the breakaway force upon actuation of the plug 32, on the other hand, the plug 32 is designed as a multi-component, in particular a two-component, configuration considered to be independently inventive. In detail, the plug 32 is designed according to one aspect of the invention in the unpublished European patent application No. 22206993.2, the disclosure of which with regard to the design of the plug 32 is incorporated in its entirety ("incorporation by reference").

[0034] The plug 32, which according to one aspect of the invention is designed as a two-component or "2K plug", comprises a central plug body 34 made of a comparatively hard plastic, in the exemplary embodiment and according to one aspect of the invention made of polypropylene (PP), which is surrounded by a sealing jacket 36 made of a comparatively softer plastic material, in the exemplary embodiment and according to one aspect of the invention TPE. The central plug body 34 essentially serves to provide dimensional and structural stability and to transmit the introduced forces, in particular in the longitudinal direction when the plug 32 is displaced within the syringe body 12. For this purpose, the central plug body 34 can be provided on the inside with a receiving channel 38, for example with a thread, via which a connection to an external actuating means, for example the actuating element 10 or the actuating plunger of the syringe 1, is possible.

[0035] According to a further aspect of the invention, which is considered to be independent and independently inventive, the syringe body 12, thanks to the described design, is specifically designed for a highly efficient manufacturing and filling process suitable for large quantities. In a first step, as described above, the hollow body 12, which is closed at the end by the closure body 24, is produced as a 2K or hybrid component. Furthermore, the stopper 32 is provided. According to one aspect of the invention, the hybrid body comprising the hollow body 12 and the integrated closure body 24 is manufactured in compliance with the specifications and regulations for primary packaging, so that it can be transferred directly, without detours and without further intermediate steps, from the injection molding system to the filling system.The intermediate steps of washing, siliconizing or sterilizing that would otherwise be necessary in this context are no longer necessary, which means a considerable simplification of the process.

[0036] During filling, i.e. in the filling system, the hollow body 12 provided with the closure body 24 is then aligned vertically, i.e. with its longitudinal axis parallel to the earth's gravity, according to a further aspect of the invention, in such a way that the proximal end 8, which is still open in this state, points "upwards" and the distal end 4, closed with the closure body 24, points "downwards", i.e. towards the earth. The filling of the syringe body 12 with the active ingredient can then begin. According to one aspect of the invention, this takes place in a large-scale filling system in which a large number of syringe bodies can be filled in parallel and simultaneously. After the intended amount of active ingredient has been introduced into the hollow body 12, the stopper 32 is finally pushed into the proximal end 8 of the hollow body 12 and thus closes the interior filled with the active ingredient. The filled tip body 12 is then ready for the subsequent processing steps.

[0037] In a further processing step, which can take place before or after the syringe body 12 is filled, the latter is connected to the needle holder 6. The syringe 1 is intended for making the syringe body 12 already connected to the needle holder 6 available to the user; transport and storage of the pre-filled syringe 1 is thus provided with the needle holder 6 already attached. In order to meet the highest requirements for the storage stability of the active ingredient, the syringe 1 is designed as a so-called dry needle system, in which contact between the syringe needle and the active ingredient is consistently avoided during storage or transport. To make this possible, the syringe body 12 shown in perspective in FIG. 3 and in FIG.4, the needle attachment 6 shown enlarged in longitudinal section is provided with a needle system 40 forming the syringe needle, which comprises on the one hand an injection needle 42 and on the other hand a septum needle 44 connected to the latter on the fluid side.

[0038] In a design quite common for such dry needle systems, the injection needle 42 is provided in the manner of a "conventional" syringe needle for piercing the patient's skin during treatment, with the septum needle 44 being oriented "inwards", i.e., towards the active ingredient container, and intended to pierce the septum 28. The fluid-side connection of the injection and septum needles 42, 44 to one another thus creates a fluid-side connection between the interior of the active ingredient container and the injection needle 42 after the septum 28 has been pierced, so that the active ingredient can be dispensed from the syringe body 2 via the injection needle 42. In the exemplary embodiment, and in a quite common design, the injection needle 42 and the septum needle 44 are formed by the two opposite ends of a common hollow needle 46.This hollow needle 46 is mounted and fixed in a base body 50 forming the actual needle holder of the needle attachment 6, preferably made of a hard plastic such as PP, POM or PC.

[0039] In such dry or double-needle systems, it is of considerable importance that the septum needle 44 reliably pierces the septum 28 when the syringe 1 is prepared for the application of the active ingredient, so that the fluid-side connection of the active ingredient reservoir to the injection needle 42 required for the administration of the active ingredient can be reliably established. On the other hand, however, it must be ensured that the septum needle 44 can be reliably kept at a distance from the septum 28 during transport, storage, or other handling, so that the latter cannot be inadvertently damaged by the septum needle 44, which could lead to contamination of the active ingredient or loss of the active ingredient.

[0040] According to an aspect considered to be independently inventive, these requirements are achieved with the syringe 1 through a targeted use and design of the screw connection provided for attaching the needle attachment 6 to the syringe body 2.

[0041] To produce the screw connection on its base body 50, according to one aspect of the invention, the needle attachment 6 comprises, in a connection area 52 on the outside, an external thread 54 adapted to the internal thread 16 of the syringe body 2, such that the external thread can be screwed into the internal thread 16. In the exemplary embodiment, according to one aspect of the invention, corresponding to the design of the internal thread 16, the external thread 54 is designed as an external Luer thread 54. As a further component, the needle attachment 6 is also provided, according to one aspect of the invention, with a needle protection cap 56 slipped onto the base body 50 of the needle holder 6. For this purpose, the needle protection cap 56 is provided with a circumferential internal groove 58, which engages with a corresponding external bead 60 on the base body 50 when the needle protection cap 56 is pushed onto the base body 50.This ensures that the needle protection cap 56 is positioned and secured in a precisely defined position relative to the base body 50 when attached to the base body 50. At the end, the needle protection cap 56 also includes a circumferential cover skirt 62, which, when the needle protection cap 56 is properly positioned and rusted, encloses and covers part of the external Luer thread 54 on the outside.

[0042] When assembling the needle attachment 6 on the syringe body 12, by screwing the external thread 54 into the corresponding internal thread 16 of the syringe body 2, the hollow needle 46, which is mounted centrally in the base body 50, is introduced with its end forming the septum needle 44 into the free internal channel within the fixing apron 30, wherein the advance of the septum needle 44 within the free internal channel of the fixing apron 30 is generated by the advance when screwing the external thread 54 into the internal thread 16.The desired preliminary positioning and fixation of the septum needle 44 in a position within the fixation apron 30, in which it does not yet reach the septum 28 or at least does not yet completely pierce it and thus neither damages nor destroys it, is achieved according to an aspect of the invention considered to be independently inventive by the design and dimensioning of the cover apron 62 of the needle protection cap 56 in combination and in interaction with the components of the syringe body 2. As the external thread 54 is increasingly screwed into the internal thread 16, the end edge 64 of the cover apron 62 strikes the end face 66 of the connecting piece 14. This thus forms an end stop for the cover apron 62 and thus for screwing in the needle attachment 6 as a whole; further screwing in is then initially no longer possible.The geometric parameters of the components mentioned, i.e. in particular the covering area of ​​the covering apron 62 with regard to the position of the end face 66 and the position of the septum 28 within the hollow body 12, are coordinated with one another according to an independently inventive aspect in such a way that the septum needle 44 is still positioned sufficiently far away from the septum 28 when the end edge 64 abuts the end face 66 and does not reach it.

[0043] In a further embodiment considered to be independently inventive, a rotary locking mechanism is provided between the base body 50 of the needle holder 6 and the needle protection cap 56. For this purpose, in the embodiment considered to be independently inventive, according to the exemplary embodiment, a driving rib 67 extending in the longitudinal direction is formed on the outside of the base body 50 of the needle holder 6 at its end, which driving rib 67 engages, when the needle protection cap 56 is pushed on, in a corresponding driving groove 68 introduced into the inside of the cover apron 62, as can be seen from the enlarged longitudinal section in FIG. 4. The rotary locking mechanism formed by the combination of the driving rib 67 and the driving groove 68 encompassing it thus fixes the base body 50 in rotation relative to the needle protection cap 56, and by rotating the needle protection cap 56 about its longitudinal direction, the base body 50 of the needle holder 6 located therein can be rotated along with it.Of course, such a rotary locking mechanism between the base body 50 and the needle protection cap 56 can also be represented in another way, for example a driving rib formed on the inside of the cover apron 62 and running in the longitudinal direction and a corresponding driving groove positioned on the outside of the base body 50.

[0044] The syringe 1 assembled to this extent, in which the needle attachment 6 provided with the pushed-on needle protection cap 56 is screwed onto the syringe body 2 up to the aforementioned stop, is shown in FIG. 5 in longitudinal section and in a partial enlarged view in FIG. 6. It is clearly visible that the external thread 54 engages with approximately one thread turn into the internal thread 16 and the end edge 64 rests directly on the end face 66 of the connecting piece 14. This ensures a mechanically stable and resilient connection of the needle attachment 6 to the syringe body 2. Further screwing of the external thread 54 into the internal thread 16 is no longer possible due to the stop. In this position, the free end of the septum needle 44 cannot reach the septum 28, and this is thus protected from damage by the septum needle 44 and remains intact.In this state, the prefilled syringe 1 can thus be safely stored and transported, whereby the septum needle 44 is reliably kept “dry”, ie cannot come into contact with the active ingredient inside the syringe body 2.

[0045] To administer the active ingredient, i.e., to use the syringe 1, the needle protection cap 56 is then removed, preferably immediately before use, so that the injection needle 42 is accessible. For this purpose, the needle attachment 6 is now rotated further by accessing the needle protection cap 56 beyond the stop temporarily formed by the locking system comprising the internal groove 58 and the bead 60, by applying a suitable increased torque, wherein the rotation is transmitted from the needle protection cap 56 to the base body 50 via the aforementioned rotational locking mechanism. As a result, the external thread 54 on the base body 50 is screwed further into the internal thread 16 in the connecting piece 14, wherein the septum needle 44 is moved further toward the septum 28.The needle protection cap 56 cannot be moved longitudinally due to the stop formed by the edges 64, 66, so that it is increasingly lifted off the base body 50 and can finally be removed. Together with the needle protection cap 56, its covering skirt 62 is also removed, so that the contact of its end edge 64 with the end face 66 of the connecting piece 14 is eliminated. In this sense, the needle protection cap 56 can also be considered a tamper-evident closure, since its removal makes it clear that the medication has already been used. The syringe 1 with the needle protection cap 56 removed is shown in longitudinal section in FIG. 7.

[0046] It is clearly visible that in this situation, the external thread 54 has been screwed further into the internal thread 16. As a result of such further screwing, the threaded connection generates a feed of the needle attachment 6 in the direction of the proximal end 8 of the syringe body 2. This feed also transports the septum needle 44 in the direction of the septum 28. A particular advantage of this arrangement is that, by translating the rotary movement into a feed movement by means of the threaded connection, depending on the selection and design of the thread parameters, a very stable, mechanically well-guided, and very finely metered feed can be generated, so that the septum needle 44 can be positioned and moved with particular precision.

[0047] By screwing it in further, the septum needle 44 can be moved so far toward the proximal end 8 that it pierces the septum 28, thus establishing the fluid-side connection between the injection needle 42 and the interior of the syringe body 2 and thus the active ingredient reservoir. The syringe 1 in this, now ready-to-use state is shown in longitudinal section in FIG. 8. In this state, in which the septum needle 44 protrudes through the membrane 28 into the active ingredient reservoir, the plug 32 can be displaced toward the distal end 4 and thus toward the closure body 24 within the hollow body 12, so that the active ingredient is pressed out of the interior through the hollow needle 46.Furthermore, in the exemplary embodiment, according to an aspect considered to be independently inventive, especially in combination with the components described above, the needle attachment 6 or needle holder attachable to the hollow body 12 is provided with an integrated needle protection system. This takes into account the fact that there is a growing need, and this has already been incorporated into legal or regulatory provisions, to equip medical syringes with so-called needle protection systems. Increasing legal requirements for a safe working environment in various countries, for example, oblige employers in the medical sector to protect their employees from needlestick injuries.For this purpose, it may be possible, for example, to provide a system of protective caps that are placed over the needle when it is not in use, or so-called retraction systems may be provided in which the needle is retracted after use into the syringe casing, which has meanwhile been emptied of the active ingredient, so that the needle tip is no longer exposed.

[0048] In the present case, according to one aspect of the invention, a needle protection sheath 70 is pivotally attached to the base body 50 of the needle attachment 6 via a joint 72 for this purpose. The needle protection sheath 70 is formed by an elongated protective body 74, the length of which exceeds the free length of the injection needle 42 and thus projects beyond it at the end. Furthermore, the width of the protective body 74 is selected such that it significantly projects beyond the injection needle 42 on both sides. The protective body 74 can also have a receiving groove on the inside into which the injection needle 42 can be embedded in the position of the protective body 74 shown in FIG. 8. A cover plate 78 is formed on the end of the protective body 74 and covers the free end of the injection needle 42 in the position shown there.In the position shown, the free end of the injection needle 42 is thus completely shielded, and no contact and thus no injury from the hollow needle 46 is possible.

[0049] The system is in this position when the outer protective cap 56 is removed. Since the hollow needle 46 is still shielded by the protective body 74 in this state, insertion of the needle 46 is not yet possible. To make it usable, an actuating element 80 integrally formed on the protective body 74 pivots the needle away from the hollow needle 46 around the joint 72, so that it is now exposed and released. In this state, the syringe 1 is now ready to dispense the active ingredient.

[0050] Further aspects of this needle protection system are set out in detail in the unpublished European patent application No. 22174670.4, the disclosure of which with regard to the design of the needle protection system is incorporated in its entirety ("incorporation by reference"). In particular, after use of the syringe 1, the protective body 74 can be pivoted back around the joint 72 so that it once again shields the injection needle 42 as described above and thus injuries from contact with the needle 42 are reliably avoided. However, in order to further reduce the risk of injury from the needle 42 then in use, a further aspect of the invention provides for the protective body 74 to be pivoted even further around the joint 72 until the injection needle 42 breaks off in its needle bearing in the base body 50.This definitively fixes the needle 42 in its position within the shielding area of ​​the protective body 72, and also immediately indicates that the syringe 1 has already been used and that the (now used) syringe body 2 should be disposed of together with the now broken needle 42 still attached to it. This reliably eliminates errors and confusion, which could, for example, lead to the accidental reuse of the syringe 1.

[0051] The attachment of the above-mentioned components of the needle guard 70 to the hollow needle 46 can be carried out in a single, joint work step in the manner of “overmolding”.

[0052] The exemplary embodiment shows an actuating element 10 which, in the manner of a conventional design, comprises an actuating plunger 84 arranged on a handle 82, which, after the syringe body 2 has been attached to the handle 82, acts on the stopper 32 and enables its displacement towards the distal end 4. Alternatively, the actuating element 10 can also be designed as a conventional syringe handle or as an automated actuating element 10 in the manner of an auto-injector. The connection of the actuating element 10 to the syringe body 2 can be implemented in various variations, for example as a screw, plug, or click connection. This takes into account the fact that there is an increasing need, and in some cases has already been incorporated into legal or regulatory requirements, to equip medical syringes with so-called needle protection systems.Increasing legal requirements for safe working environments in various countries oblige employers in the medical sector, for example, to protect their employees from needlestick injuries. This can be achieved, for example, by providing a system of protective caps that are placed over the needle when not in use, or by providing so-called retraction systems, in which the needle is retracted into the syringe barrel after use, which has since been emptied of the active ingredient, so that the needle tip is no longer exposed.

[0053] List of reference symbols

[0054] 1 medical syringe

[0055] 2.2' syringe body

[0056] 4 distal end

[0057] 6, 6' needle attachment

[0058] 8 proximal end

[0059] 10 Actuating element

[0060] 12 hollow bodies

[0061] 14 connecting pieces

[0062] 16 Luer internal thread

[0063] 18 threaded space

[0064] 20 connecting pins

[0065] 22 connecting channel

[0066] 24 closure bodies

[0067] 26 Central Area

[0068] 28 Membrane, septum

[0069] 30 Fixation apron

[0070] 32 plugs

[0071] 34 plug bodies

[0072] 36 Sealing jacket

[0073] 38 recording channels

[0074] 40 needle system

[0075] 42 Injection needle

[0076] 44 Septum needle

[0077] 46 hollow needle

[0078] 50 basic bodies

[0079] 52 Connection area

[0080] 54 external threads

[0081] 56 Needle protection cap

[0082] 58 inner groove

[0083] 60 bead

[0084] 62 Cover apron edge

[0085] frontal surface

[0086] Driving rib Driving groove Needle protection cover

[0087] joint

[0088] protective body

[0089] Cover plate actuating element handle

[0090] Actuating plunger

Claims

Claims 1. A medical syringe (1) comprising a syringe body (2) having an active ingredient container, the active ingredient container being sealed by means of a pierceable membrane (28) arranged in the region of the distal end (4) of the syringe body (2), and comprising a needle attachment (6) which can be attached to the syringe body (2) and which carries a needle system formed by an injection needle (42) and a septum needle (44) connected to the latter on the fluid side, the needle attachment (6) being attachable to the syringe body (2) by means of a screw connection.

2. Medical syringe (1) according to claim 1, wherein screwing the needle attachment (6) into the syringe body (2) causes the septum needle (44) to be propelled in the direction of the pierceable membrane (28).

3. Medical syringe (1) according to claim 1 or 2, wherein the screw connection is designed as a Luer connection.

4. Medical syringe (1) according to one of claims 1 to 3, wherein the septum needle (44) pierces the membrane (28) arranged in the syringe body (2) when the screw connection is complete.

5. Medical syringe (1) according to one of claims 1 to 4, wherein the screw connection is formed by an external thread (54) arranged on a base body (50) of the needle attachment (6) and an internal thread (14) of a connecting piece (14) of the syringe body (2) adapted to this.

6. Medical syringe (1) according to claim 5, wherein the needle attachment (6) comprises a needle protection cap (56) which partially surrounds the external thread (54) by means of a covering apron (62) formed on the end.

7. Medical syringe according to claim 6, the covering apron (62) is arranged and dimensioned such that, when its end edge (64) rests against the end face (66) of the connecting piece (14), the septum needle (44) is spaced from the membrane (28) in the syringe body (2).

8. Needle attachment (6), in particular for use with the syringe body (2) of a medical syringe (1) according to one of claims 1 to 7, with a base body (50) which carries a needle system formed by an injection needle (42) and a septum needle (44) connected to the latter on the fluid side, and which is provided on the outside with an external thread (54), and with a needle protection cap (56) which partially surrounds the external thread (54) by means of a covering apron (62) formed on the end.

Images