Patent Description:
In the areas of medical device design, manufacture, assembly, distribution and sale of medical devices, it has become important to have the ability to track the history of individual devices or lots of devices from early in the manufacturing life through to the end use of the device. For injection devices, such as auto-injectors, traceability and connectivity of the injection devices, as well as data recording and retrieving, is becoming the norm. Such a data carrier system should be integral with medical devices, preferably starting with a component of the device that represents the very beginning of the manufacturing or product life cycle. For example, the use of RFID tags (chips) should allow data writing and data reading through the entire history of the medical device, including data from the pharmaceutical manufacturer, the fill/finish process, the device assembly steps, the distribution centers, all the way through to the end user, the health care providers and patients. With incorporation of an RFID tag into such a device component, product and process and event history that builds up over the history of the device can be stored like a pedigree on the device itself without the requirement to store the relevant information in a separate or remote data-base, that requires access to information from each of the different parties involved with the manufacture, distribution and use of the device.

Such a tracking system is also useful in device quality control whereby specific physical, mechanical and chemical criteria are met, to ensure proper mechanical function of the device. In the case of injection devices, this includes criteria that arise during the syringe manufacturing process as well as during the device manufacturing, filling and packaging/assembly process. Having quality control data written to and read from individual devices will minimize scrap rates thus reducing the loss associated with expensive medicaments that are pre-filled into such devices. In the case of quality complaints from end users regarding specific components of the device or the entire final device itself, sometimes it is not easy, to clearly identify the root cause and have at the same time traceability to identify the relevant products based on additional information that is linked to each product.

In light of the above desires and goals relating to injection devices there exists a need for providing a single solution that allows tracking of an injection device. The present invention satisfies these goals and needs by providing an RFID tag enabled needle shield assembly that stays with the device from the beginning of the manufacturing process right up to the moment before a user begins an injection of medicament. Other benefits and objectives of the invention will become evident from the following more detailed description and included drawings.

<CIT> describes a protective cap comprising means for transmission of data. <CIT> describes systems and methods for managing information relating to medical fluids and containers therefor.

An injection device for administering medicament is described, comprising:
a syringe prefilled with medicament and having an attached injection needle having a distal end; and a needle shield assembly for providing a sterile enclosure of an injection needle fixedly attached to the syringe, the needle shield assembly comprising: an interior portion comprising a material that forms a sterile and fluid tight seal with a distal end of an injection needle; and an RFID tag fixedly attached to the needle shield assembly; the injection device further comprising a needle cover remover configured to remove the needle shield assembly before administering an injection of the medicament through the needle. An RFID tag that is configured as a read-write device that can store data throughout the product life cycle and can be read by an RFID reader as often as needed throughout the product life cycle is fixedly attached to the needle shield assembly. In some cases, it may be beneficial that the RFID tag be a read-only having a memory that contains only unique product identification data.

The needle shield assembly can further comprise a rigid outer cover and a soft inner cover, where the rigid outer cover is attached to the soft cover such that axial movement of rigid outer cover causes axial movement of the soft inner cover. In some cases, the RFID tag is preferably fixedly attached to the rigid outer cover. This can be achieved by one of a variety of fasteners, for example, a snap fit, an inlay, co-molding, an adhesive, lamination, tape, a press fit or a combination of any of these attachment methods. The needle shield assembly can also have an antenna in electrical communication with the RFID tag.

Another aspect of the invention relates to methods of tracking the life cycle of a medicament container comprising the RFID tag enabled needle shield assembly or the injection device incorporating the needle shield assembly from a point in time where the RFID tag is attached to a needle shield and the assembly is then removably attached an injection needle connected to a medicament container, such as a syringe barrel, to form a sterile and fluid tight seal with a distal end of the injection needle. Data is read from or written to this RFID tag as the medicament container moves through multiple manufacturing processes, such as, siliconization, medicament filling, shipping, quality control testing, warehousing, incorporation with or in other components to make a complete injection device.

These, as well as other, advantages of the various aspects of the RFID tag enabled needle shield, and the manner of attaining them, will become apparent to those of ordinary skill in the art by reading the following detailed description, with appropriate reference to the accompanying drawings.

The invention will now be described in more detail and with reference to the appended drawings in which:.

The ability to track the history or product life cycle of a medical device from the early beginnings of the manufacturing and assembly of the device through to its ultimate end use, while also having the ability to read and write data to the device throughout that history is an important benefit in assuring that only high quality and safe medical devices reach the ultimate end users. In the field of injection devices, particularly those that utilize pre-filled syringes containing medicaments, it has been found that the incorporation of an RFID tag into a single device component that is assembled as part of the device or a portion of the device early in its history will provide an accurate tracking or traceability of a specific device or particular lots of devices. Typically, injection devices are comprised of a main housing that encloses the mechanism for the setting a dose of medicament and/or for delivering a dose of medicament contained in a separate container within the main housing or attached to the main housing. <FIG> illustrates one example of an injection device that can be used in my invention. This particular injection device is an auto-injector.

The drug delivery device <NUM> shown in the drawings comprises a front or proximal end <NUM> and a rear or distal end <NUM>. The front end <NUM> comprises a generally tubular front body <NUM> having elongated openings <NUM> for viewing a syringe <NUM> as shown in <FIG> and <FIG> and having a somewhat narrowing front end 12a (see <FIG>). The rear end <NUM> of device <NUM> has a rear tubular rear body <NUM> that is joined with front body <NUM> with connection <NUM> (see <FIG>), where one part of the connection <NUM> is on the front body <NUM> and the cooperating and mating connector is on the rear body <NUM>. Inside the front body <NUM> is a needle shield <NUM> that is axially slidably arranged. The needle shield <NUM> is generally tubular with a first front part <NUM> having a certain diameter and a second rear part <NUM> having a diameter larger than the front part <NUM>, where these parts are joined by an intermediate conical part <NUM>. Two elongated grooves <NUM> are arranged along the needle shield <NUM>, on opposite sides of the needle shield <NUM>, also for viewing the syringe and guiding axial movement of the outer body <NUM>. On the inner surface of the conical part <NUM> a circumferential ledge <NUM> is arranged. At the rear end of the needle shield <NUM> two openings <NUM> are arranged opposite each other, where each opening <NUM> is arranged with somewhat inwardly projecting, flexible, tongues <NUM>.

A syringe carrier assembly <NUM> is arranged inside the needle shield <NUM> and is axially slideable in the proximal direction. The syringe carrier assembly <NUM> as shown in <FIG> comprises an outer body <NUM> and an inner body <NUM>, both of which are preferably tubular in shape, with the inner body <NUM> fitting within, and being slideable relative to the outer body <NUM>. The syringe <NUM> is positioned within the inner body <NUM> such that there is no relative axial movement between the syringe and the inner body <NUM>. Plunger <NUM> is in contact with the stopper 16d of the syringe <NUM>. This contact between the plunger <NUM> and the stopper 16d prevents the syringe <NUM> from moving in a distal direction. Also prohibiting movement of the syringe <NUM> within and relative to the inner body is the pointed tongues <NUM> that is part of the cap assembly <NUM>. These tongues grab the needle protection shield 50b that has attached an RFID tag <NUM> and assists in holding the syringe <NUM> in place until cap <NUM> is removed prior to use of the device. There are no direct attachments or connections between the syringe and the inner body. The proximal end 56c of the inner body <NUM> is tapered or narrowed to accommodate the proximal end of syringe <NUM> when it is placed within the inner body <NUM>. The outer body <NUM> fits over the inner body <NUM> in a manner that allows relative axial movement between the inner body <NUM> and the outer body <NUM>.

Because the syringe <NUM> moves axially with the syringe carrier assembly <NUM> during the injection process, at some point in that process the syringe carrier assembly <NUM> will encounter a hard stop 12b on the inside surface of the front body <NUM> that stops the forward or proximal movement of the assembly <NUM>. In order to prevent damage to the syringe <NUM> and/or to prevent the phenomenon of kick-back that can be experienced as an undesirable tactile feeling to the person receiving the injection, it is desirable to provide a force dissipation mechanism to minimize or eliminate these possible negative consequences. One such force dissipation mechanism includes a dampener ring <NUM> that is employed as a third component of this syringe carrier assembly <NUM>. The dampener ring <NUM> is fitted over the outside surface 56a of the inner body <NUM> or alternatively fitted into cup portion 57a at the distal end of outer body <NUM> and abutting distal facing inner lip 57b.

The inner body <NUM> is also a hollow tube having tapered or narrowing open proximal end 56c that has an internal shape to accept and hold the proximal end of syringe <NUM> allowing only the staked needle 16c and/or needle hub assembly 16b to protrude proximally from the inner body <NUM>, see <FIG>. The distal end of the inner body <NUM> terminates in a flange configuration that has a diameter greater than the outer diameter of the inner body <NUM>. The flange provides a distal bearing surface for abutment with syringe flange and a proximal bearing surface <NUM> for abutment with the distal bearing surface of the dampener ring <NUM>.

Although the inner body <NUM> and outer body <NUM> can move axially relative to each other, the inner and outer bodies are fixed rotationally to each other, i.e., the two bodies cannot rotate relative to each other. As described above, plunger <NUM> is in contact with the stopper 16d of the syringe <NUM>. This contact between the plunger <NUM> and the stopper 16d prevents the syringe <NUM> from moving in a distal direction. Also prohibiting movement of the syringe <NUM> within and relative to the inner body is the pointed tongues <NUM> that is part of the cap assembly <NUM> (see <FIG>). These tongues grab the needle protection shield 50b and assists in holding the syringe <NUM> in place until cap <NUM> is removed prior to use of the device. There are no direct attachments or connections between the syringe and the inner body. The proximal end 56c of the inner body <NUM> is tapered or narrowed to accommodate the proximal end of syringe <NUM> when it is placed with the inner body. The outer body <NUM> fits over the inner body <NUM> in a manner that allows relative axial movement between the inner body <NUM> and the outer body <NUM>.

Attached to the staked needle hub 16b that holds needle 16c of syringe <NUM> is a needle protection shield 50b that is friction fitted to the staked needle hub 16b of the syringe <NUM>. The needle protection shield 50b is surrounded by needle shield grabber <NUM> having sharp pointed tongues <NUM> directed somewhat inwards and towards the front or proximal end of the device. The needle shield grabber <NUM> is operatively connected with cap <NUM> such that removal of cap <NUM> results in simultaneous removal of needle protection shield 50b and grabber <NUM>.

The needle shield 50b is typically added to the stacked needle hub 16b by the manufacture of the medicament container, typically a syringe manufacture, as part of the pre-filled syringe manufacturing process prior to the medicament container being filled with the medicament. In addition to fabricating the actual container (glass or plastic), the syringe manufacturer will also be responsible for attaching (staking) needle 16c to hub 16b and also for forming siliconization of the inside of the syringe. Of course, prior to this manufacturing step, the needle shield assembly must be fabricated, as discussed, below in more detail. The fabricator of the needle shield assembly of the invention will combine the RFID tag with the material used to form the needle shield. At this early point in the overall injection device manufacturing process, the RFID tag is capable of storing data that will allow historical tracking. The syringe manufacture will receive the RFID tag enabled needle shield assemblies and needle cannula from another manufacture and will combine these two components as part of the syringe manufacturing process. Again, at this point, the RFID tag can store information inputted by the syringe manufacturer that relates to the cannula source, such as dates, lot numbers, cannula manufacturer identification, locations, etc. As mentioned, the syringe manufacturer can also add data to the RFID relating to siliconization parameters, dates, formulas, testing criteria, etc. Once complete, the syringe with the needle shield assembly is then transferred directly to a medicament filling location or stored/warehoused until shipped to a filling location. Again, data can be written to or read from the RFID tag to track and/or record information relating to the product history.

The medicament filling process is typically performed by another manufacturer, namely a pharmaceutical company or a contract filling company. Again, because the RFID needle shield is attached to the syringe prior to medicament filling, the filling manufacturer can read and write information to the RFID tag relating to medicament, i.e., lot numbers, dates of manufacturing, warnings, safety information, instructions for use, dose limitations, etc. By including the RFID tag as part of the needle shield assembly, this allows tracking and data collection very early in the overall manufacturing process of the complete injection device. Because the needle shield assembly remains on the syringe up until the moment a user of the complete injection device performs the injection, the RFID tag is capable of storing data relating to almost the complete history of injection device. Typically, there are many parties involved in the component and manufacturing processes that result in a finished injection device. These various parties also typically are located in many different physical locations. These parties can include the following:.

Each of the above parties may have different quality and product specific criteria that they control individually and which they document independently from the other parties. Once the syringe has been filled with medicament it is then stored or shipped directly to a location where it is eventually incorporated into a completed injection device. Again, information can be read from or written to the RFID tag relating to storage and shipment of the pre-filled syringe.

The injection device assembly process typically joins or marries the pre-filled syringe with the RFID tag enabled needle shield with the various metal or plastic components that form the working parts of injection device, i.e. dose mechanism, and that cause the medicament in the syringe to be forced through the needle 16c. During the device assembly step data can be written to and/or read from the RFID tag. Additionally, a second RFID tag may accompany one or more components of the dose mechanism. This second RFID tag would contain historical data relating to the manufacture of these components. Once the pre-filled syringe was incorporated with the dose mechanism data on each of the RFID tags could be exchanged thus ensuring that each RFID tag contained the complete product history for a completed injection device.

<FIG> illustrates one possible needle shield design that comprises a rigid sheath <NUM> surrounding and enclosing a flexible needle sheath <NUM> that is made from a material that is softer than the material used to fabricate the rigid sheath <NUM>. Preferably, the flexible needle sheath <NUM> comprises a rubber material, however, any material can be used that will allow the injection needle 16c to fit within cavity <NUM> maintaining sterility and creating a liquid seal with the injection needle. Preferably, the sharp proximal end of the needle 16c is embedded into the proximal end of cavity <NUM> and into the flexible needle sheath material. The flexible needle sheath <NUM> can be friction fitted within the rigid sheath or alternatively held in place with an adhesive or other connection means.

In the embodiment shown in <FIG> an RFID tag <NUM> is embedded in the proximal end of the rigid shield <NUM>. This can be achieved through a co-molding manufacturing process. In one possible manufacturing process a core pin <NUM> (see <FIG>) is used to support the RFID tag <NUM> while molten plastic material is used to form the rigid sheath <NUM> and to encapsulate the RFID tag <NUM>. One or more support pillars <NUM> are located within the pin cavity or cage <NUM> to support the RFID tag to prevent bending or cracking of the RFID tag during the molding process. One or more robotic tools are used to select, write data, and place the RFID tag in position for the co-molding process. Other robotic tools are used to remove the co-molded RFID tag enabled needle sheath from the fabrication process.

<FIG> show alternative manufacturing techniques to incorporate into or associate the RFID tag <NUM> with rigid sheath <NUM>, each of which uses a snap-in feature <NUM>, where the RFID tag is held in place with flexible arms, fingers, or channels that are integrally formed in an outside surface <NUM> or an inside surface <NUM> of rigid sheath <NUM>. <FIG> in particular illustrates that the fitting of the flexible needle sheath <NUM> within the rigid sheath <NUM> can be used as ram to seat the RFID tag <NUM> into snap fittings <NUM>. Although <FIG> illustrate the use of both a rigid sheath and a flexible needle sheath as two separate components, it is within the scope of the present invention to incorporate the RFID tag into a needle shield component that is fabricated as a single component, i.e., where the rigid outer portion is integral with a soft flexible inner portion that is capable of sealing the proximal end of the injection needle. Such a single component needle shield that provides both a rigid and a soft needle sheath could be fabricated as individual portions of different hardness materials and then physically and permanently attaching two distinct portions together. It may also be possible to form the single component needle shield by a co-molding process. In this way only a single needle shield need be manufactured as opposed to manufacturing two separate and different components that must then be first assembled together prior to assembling the needle shield assembly to the syringe and injection needle.

Yet another alternative design of the needle shield assembly 50b incorporates an antenna feature. Two possible embodiments are shown in <FIG> where an antenna <NUM> is attached and formed around the outside surface of rigid sheath <NUM> or alternatively printed on the surface of the sheath. In either case the antenna is electrically connected to the RFID tag <NUM>. The use of the antenna will improve both the writing and reading of the RFID tag, especially when the RFID tag is embedded and covered during a co-molding manufacturing process. <FIG> shows the antenna feature connected to the RFID tag prior to the antenna being bent or formed around the outside surface of the rigid sheath. An adhesive or coating can be used to hold the antenna <NUM> to the surface of the rigid sheath.

The RFID tag can be a read only device, but more preferably it is a read-write RFID. The RFID tag can be based in different frequency bands, including those that work in HF-RFID and NFC frequency or UHF frequency. The interaction and reading of the information take place with industrial RFID readers for UHF/HF frequency, handheld readers and accessories and common smartphones that implement NFC Technology.

The RFID has a memory that can be read and/or written to using an RFID reader and similar devices. Data stored in the memory is typically separate from a unique identifier, e.g., a serial number, of the RFID tag, which cannot be altered or erased. The storage capacity of the RFID tag should be selected so that it accomplishes the goals of data retention and retrieval, for example, the goal may be to record the entire product history of the device up until the time of use by the end user or it may only need to have memory capacity sufficient to retain information regarding the medicament, such as, dosing and safety information. Higher memory allows RFID tag to store manufacturing data, quality control related information, medicament information, user instructions and any other criteria that allows for a storing of the complete history of the product life cycle. In general, the memory of each RFID tag attached to each needle shield assembly should be sufficient to store data collected at the different points in the product life cycle.

Predefined information will be transformed to a set of data that is then wirelessly transferred to each RFID tag at the outset of the product life cycle. In some cases, it may be possible and desirable to perform a "bulk" transfer of data to a tray full of needle shield assemblies, each having an attached RFID tag. Data transfer on an individual basis could be accomplished by the above-mentioned robotic tool as the needle sheath is removed from the co-molding or RFID attachment process. Bulk transfer of information to a number of RFID tag enabled needle sheaths could occur during medicament filling process or during actual device assembly. As such, in each of the manufacturing and/or assembly steps, e.g. syringe manufacturing, syringe filling, shipping, device assembly, etc., individual item related information will be written to the individual RFID tags or written in "bulk" to a number of RFID tags in an assembled lot. Preferably, the written data is secured and protected through known data security techniques, such as, encryption.

Considering the number of possible designs that injection devices may embody, it is likely that the medicament holding container, e.g., a prefilled syringe, will have a separate manufacturing route compared to that of the main housing injection device that holds the dose delivery mechanism. Late in the device assembly process the two parts, medicament container with the RFID tag and the dose delivery mechanism, are eventually joined to form the complete injection device. In such cases, it is desirable to employ a second RFID tag attached to the main housing of the dose delivery mechanism or to a component within the housing such that a record of the dose delivery mechanism can be tracked and traced independent of the manufacturing and testing of the medicament container that contains the needle shield assembly with the RFID tag. Once the two RFID tags become part of a single device assembly, the data can then be read from each RFID tag or the data can be transferred from one RFID tag to the other. Data exchange between the two RFID tags becomes important because if a problem occurs during injection or after a first injection is performed it is likely that the needle sheath has been removed and disposed of, thus making product life cycle data recovery impossible. However, because data is exchanged between the RFID tag in the needle sheath with the second RFID tag in the device, data can still be recovered in the event the needle shield is no longer available. Since data was transferred from the RFID tag on the needle shield assembly to the RFID tag of the dose delivery mechanism then the complete device history will be available if needed in a post-use quality control or failure analysis.

Yet a further possibility includes the use of an injection device accessory <NUM> (see <FIG>), such as a so-called loyalty sleeve that is attached to the injection device by the end user or health care provider and contains information specific to the user. The accessory can be attached directly to the outer surface of the injection device and can be configured to acquire information directly from the RFID tag associated with either the needle shield assembly, injection device, or both. Attachment can be accomplished with a clip-on or snap-on type connector such that it is easily removed and attached to another injection device. The device accessory <NUM> can include yet another RFID tag, an RFID tag reader, a microprocessor, memory, a display, and/or user interface to input information or control operation of the device accessory, including as buttons or a touch screen. The device accessory <NUM> can be configured to communicate with an external source, such as, a smart phone, and can track the functioning of the device in actual use. For example, the accessory could acquire and store injection doses and time frequencies of injections. Such information could then be accessed by a health care provider to monitor patient compliance with a treatment regime.

Examples of the types of data that can be stored on one or both of the RFID tags include:.

Turning back to the injection device <NUM>, <FIG> shows an optimal second RFID tag <NUM> attached to or embedded in the housing <NUM>. This second RFID can communicate with the RFID associated with the needle shield assembly and with the device accessory <NUM>. <FIG> shows the rear part or power unit <NUM> of the injector according to <FIG>. It comprises a plunger <NUM> formed as a tube and with an outer diameter somewhat smaller than the inner diameter of the syringe body to be used. The plunger <NUM> is arranged with a circumferential groove <NUM> with a certain width. Inside the plunger <NUM> a helical compression spring <NUM> is arranged and inside the spring <NUM> here is a spring guide <NUM>. Adjacent the groove <NUM> of the plunger <NUM> a holding member <NUM> is arranged. It comprises a ring-shaped body having an annular ledge arranged around its circumference and a number of flexible tongues <NUM> directed towards the rear or distal end of the power unit. Each tongue <NUM> is arranged with inwardly directed ledges arranged and shaped as to fit into the groove <NUM> of the plunger <NUM>. Each tongue <NUM> is further arranged with reinforcing ribs on the outer surfaces.

Surrounding the plunger <NUM> is an activator <NUM> with a mainly tubular shape. Its front or proximal end, to the left in the figures, has an inclined transition surface which meets with a band-shaped part with enlarged diameter. On the inner surface adjacent the transition surface an annular inwardly directed ledge <NUM> is arranged, with a shape as to fit into the groove <NUM> of the plunger. A number of longitudinally directed cut-outs are arranged at the front part of the actuator <NUM> so as to form flexible tongues <NUM>. The activator <NUM> is further provided with two stop ledges directed radially outwards from the outer surface on either side. The upper end of the activator <NUM> is arranged with an end wall 80a.

Outside the activator <NUM> is an actuator sleeve <NUM> is slidably arranged, also of a generally tubular form. It comprises a front end with a conical part ending in a ledge on its outer surface. At a distance from the ledge a first annular ring <NUM> is arranged the outer surface. A second annular ring is also arranged a further distance from the ledge. The rear end of the actuator sleeve <NUM> is arranged with two oppositely arranged cut-outs of a generally rectangular shape where the widths correspond to the width of the stop ledges of the actuator <NUM>. A compression spring <NUM>, hereafter named needle shield spring is surrounding the actuator sleeve.

The previously named components of the power unit are housed in a rear housing <NUM> of a generally tubular shape, where the front end of the rear housing <NUM> has a somewhat lesser diameter, corresponding to the inner diameter of the rear end of the front body and provided with a number of annular protrusions <NUM> which are intended to fit into the corresponding annular recesses <NUM> on the inner surface of the front body <NUM>.

The function of injector <NUM> described above according to the invention will now be described with respect to the embodiment shown in <FIG>. When assembling the injector, the front and the rear parts are assembled individually. As regards the power unit <NUM> the plunger <NUM> is held against the force of the compression spring <NUM> in that the inwardly directed ledges of the tongues <NUM> of the activator <NUM> are situated in the groove <NUM> of the plunger <NUM> and that the actuator sleeve <NUM> prevents the tongues <NUM> from moving outwards. Further the tongues <NUM> of the holding member <NUM> are also arranged in the groove <NUM>. The tongues <NUM> of the activator <NUM> are adjacent the tongues <NUM> as a second safety means should the tongues <NUM> move out of the groove <NUM> of the plunger <NUM>.

A syringe <NUM> is placed in the front end <NUM> within inner body <NUM> and rear body <NUM> is attached to the front body <NUM> wherein the protrusions <NUM> fit into the recesses <NUM>. Preferably the syringe <NUM> is a pre-filled syringe where a medicament is placed within the barrel of the syringe <NUM> and sealed at the distal end with a slidable stopper or piston 16d. The staked needle 16c is sealed with the needle protection shield 50b, which contains RFID tag <NUM>. The front body <NUM> and rear body <NUM> are then connected together. The needle protection cap <NUM> with needle shield grabber <NUM> is inserted into the front end of the device. The device is now ready for use.

When an injection is to be performed the needle protection cap <NUM> and attached grabber <NUM> is pulled out of the injector carrying with it the needle protection shield 50b along with RFID tag <NUM>. This causes the sharp pointed tongues <NUM> to be pushed into the rubber needle protection shield 50b and remove it from the needle hub 16b. The front end of the injector is then pressed against the injection site and the somewhat projecting front end of the needle shield <NUM> is pushed into the housing <NUM> against the force of the compression spring <NUM> acting between the second annular ring of the actuator sleeve and a ledge arranged on the actuator <NUM>. The upper end of the needle shield <NUM> is in contact with the first annular ring <NUM> of the actuator sleeve <NUM> and its movement causes the actuator sleeve <NUM> to move backwards or distally whereby a part of the band-shaped part is situated outside the front part of the actuator sleeve <NUM>.

In the embodiment shown in <FIG> that does not include a distal activation button, the device is activated when the needle shield <NUM> is pushed against an injection site causing it to retract into the housing <NUM> in the distal direction. Once fully retracted, the actuator sleeve <NUM> will release activator <NUM> causing the spring <NUM> to release, firing the device and initiating the injection sequence.

The force of the compression spring <NUM> urges the plunger <NUM> to push on the stopper 16d of the syringe. But because of the friction between stopper 16d and syringe barrel inner wall and the incompressibility of the liquid medicament in the syringe and the very small flow passage through the needle, the force will push the syringe <NUM> and the syringe assembly <NUM> forward proximally, where needle 16c will penetrate the skin of the patient. The penetration stops when the syringe carrier assembly abuts and contacts the hard stop 12b. Although the outer body <NUM> encounters the hard stop 12b inside the front body <NUM> stopping its forward motion, the inner body <NUM> and the syringe <NUM> continue to move slightly axially forward (proximally) relative to the outer body <NUM>. In the case of the syringe carrier assembly <NUM>, the dampener ring <NUM> absorbs the forward momentum compressing slightly and eventually stopping the inner body <NUM> and the syringe <NUM>. The compression and energy absorbing characteristics of the dampening ring <NUM> greatly reduces, if not eliminates, the end of injection negative tactile feel experienced by the person receiving the injection.

The force from the compression spring <NUM> now moves the stopper 16d inside the syringe and the liquid medicament is injected into the patient until the stopper 16d reaches the inner front end of the syringe barrel. When the plunger has moved this distance, its rear end has passed the ledges of the activator <NUM> and the tongues <NUM> are moved inwards. Because the compression spring <NUM> is also acting on the activator <NUM>, the activator <NUM> is moved inside the actuator sleeve. Because of this and because the needle shield spring <NUM> is acting on the actuator sleeve <NUM> it is urged forward. When now the injector is removed from the injection site, the force of the needle shield spring <NUM> pushes the actuator sleeve <NUM> and thus the needle shield <NUM> connected to it forward, whereby the needle shield <NUM> is pushed out of the front end of the injector and surrounds the needle 16c. The movement of the actuator sleeve <NUM> causes the band-shaped part of the actuator <NUM> to pass ribs arranged on the inner surface of the actuator sleeve <NUM>. These ribs prevent any attempts to push the needle shield <NUM> back into the injector because the ribs will abut the front end of the band-shaped part of the actuator <NUM>.

Claim 1:
An injection device for administering medicament comprising:
a syringe (<NUM>) prefilled with medicament and having an attached injection needle (16c) having a distal end; and
a needle shield assembly (50b) for providing a sterile enclosure of an injection needle (16c) fixedly attached to the syringe (<NUM>), characterized in that the the needle shield assembly comprises:
an interior portion comprising a material that forms a sterile and fluid tight seal with a distal end of an injection needle; and
an RFID tag (<NUM>) fixedly attached to the needle shield assembly (50b);
the injection device further comprising a needle cover remover (<NUM>) configured to remove the needle shield assembly (50b) before administering an injection of the medicament through the needle.