The present disclosure relates in one aspect to an injection device, such as a pen-type injector for expelling of preset or user-selectable doses of a medicament. In particular, the disclosure relates to an injection device comprising a detector arrangement operable to detect or to quantitatively measure a size of a dose actually set or dispensed by the injection device.

Background

Injection devices for setting and dispensing a single or multiple doses of a liquid medicament are as such well-known in the art. Generally, such devices have substantially a similar purpose as that of an ordinary syringe.

Injection devices, in particular pen-type injectors have to meet a number of user-specific requirements. For instance, with patient's suffering chronic diseases, such as diabetes, the patient may be physically infirm and may also have impaired vision. Suitable injection devices especially intended for home medication therefore need to be robust in construction and should be easy to use. Furthermore, manipulation and general handling of the device and its components should be intelligible and easily understandable. Moreover, a dose setting as well as a dose dispensing procedure should be easy to operate and unambiguous.

Typically, such devices comprise a housing including a particular cartridge holder, adapted to receive a cartridge at least partially filled with the medicament to be dispensed. Such devices further comprise a drive mechanism or expelling mechanism, usually having a displaceable piston rod which is configured to operably engage with a piston of the cartridge. The drive mechanism and the piston rod are operable to displace the piston of the cartridge in a distal direction or dispensing direction and may therefore expel a predefined amount of the medicament via a piercing assembly, which is to be releasably coupled with a distal end section of the housing of the injection device.

The medicament to be dispensed by the injection device is typically provided and contained in a multi-dose cartridge. Such cartridges typically comprise a vitreous barrel sealed in a distal direction by means of a pierceable seal and being further sealed in proximal direction by the piston. With reusable injection devices an empty cartridge is replaceable by a new one. In contrast to that, injection devices of disposable type are to be discarded when the medicament in the cartridge has been dispensed or used-up.

Some injection devices are mechanically and/or manually implemented. Here, a user has to set a dose by manually operating a dose dial, e.g. by way of rotating or sliding the dose dial relative to a housing of the injection device. For dispensing or expelling of the dose the user has to displace the dial and/or a trigger in an opposite direction. There exist pen-type injection devices, e.g. disclosed in WO 2004/078239 A1 , WO 2004/078240 A1 or WO 2004/078241 A1 having a dial extension, which is subject to a combined rotational and longitudinal displacement in proximal direction for setting of a dose and further being subject to a sliding displacement into an opposite longitudinal direction, i.e. distal direction for dispensing or expelling of the dose of the medicament. With manually operated injection devices a user has to exert a driving force onto a trigger, e.g. implemented as a dose button or trigger button. The drive mechanism is typically operable to transfer a driving force exerted by the user into a distally directed driving motion of the piston rod that is operably engaged with the piston or stopper of the cartridge filled with a medicament.

The dial extension, e.g. an assembly of numerous components of an injection device that is displaceable relative to a housing at least for the purpose of dose setting typically comprises a dose dial that is rotatable relative to the housing for setting of a dose. The dial extension may further comprise a dose button or trigger button that is depressible in the distal longitudinal direction of the housing for initiating and/or for controlling dispensing or expelling of a dose.

In order to monitor use of an injection device, e.g. for the purpose of surveying the patient’s compliance with a prescribed medication schedule such injection devices may be equipped with a detector arrangement operable to detect at least one of a time when an injection takes place and a size of a dose injected or expelled by the injection device. For determining or

quantitatively measuring a size of a dose at least one of a rotational and longitudinal displacement of at least one component of the injection device relative to another component of the injection device must be detected and/or measured.

The implementation and embedding of an electronic detector arrangement in a manually operable and/or mechanically implemented injection device is quite challenging, especially when the electronic detector arrangement should be retrofitted into an existing injection device.

It is therefore desirable to provide an injection device with an improved detector arrangement that can be easily applied and embedded with a large variety of different injection devices. The implementation of the detector arrangement should be rather smooth and should be restricted to minor modifications of only one or a few components of the injection device. Moreover, the detector arrangement should be implementable rather cost efficient and should require only a minimum of additional installation space.

Summary

In one aspect the disclosure relates to an injection device for setting and injecting pre-set of user-selectable doses of a medicament. The injection device comprises an elongated housing defining a longitudinal direction. The elongated housing is configured to accommodate a cartridge. The cartridge contains a medicament. The injection device further comprises a detector arrangement that is operable to detect a relative movement between a first element and a second element of the injection device. The first element is subject to a first movement relative to the second element along a first longitudinal direction for setting of a dose. The first element is subject to a second movement relative to the second element along a second longitudinal direction for dispensing of the dose. Here, one of the first movement and the second movement is a helical movement, i.e. the first element is subject to a combined longitudinal and rotational movement with respect to the second element. The other one of the first movement and the second movement is a sliding movement in the longitudinal direction. The sliding movement is a longitudinal sliding movement, wherein the first element is rotationally fixed to the second element. Hence, the sliding movement is not accompanied by a rotation.

Typically, the first longitudinal direction is opposite to the second longitudinal direction.

Moreover, a longitudinal component of the first movement is opposite to a longitudinal component of the second movement.

The second element comprises at least one reference element. The reference element may be a dedicated portion of the second element. It may define a positional reference for the first element. The reference element is fixed to the second element. Hence, the reference element is immobile relative to the second element. It may be permanently fixed to the second element.

The first element of the injection device comprises a tubular-shaped surface that is provided with a pattern. The pattern faces towards the at least one reference element. The pattern may be provided on the tubular-shaped surface. It can be attached to the tubular-shaped surface or may be integrated into the tubular-shaped surface. The pattern is a spatial pattern. It may comprise a spatial code and may serve to encode the first element.

The injection device further comprises a detector arrangement. The detector arrangement comprises at least one electric sensor. The electric sensor is operable to detect a positional variation of the pattern relative to the reference element. The electric sensor is further operable to generate at least one electrical signal, typically a sequence of electric signals, in response to the positional variation of the pattern relative to the at least one reference element. Hence, the at least one electric sensor is operable to generate electric signals during and in response to at least one of the first movement and the second movement of the first element relative to the second element.

The at least one electric sensor is arranged on one of the first element and the second element. The at least one electric sensor is operable or configured to directly interact with at least one of the pattern and the reference element. With some examples the at least one electric sensor is operable to detect and/or to determine a direct interaction between the pattern and the reference element. In particular, the at least one electric sensor is operable to detect and/or to determine a degree of a rotation of the first element relative to the second element when the first element is subject to a helical motion relative to the second element. Moreover, the at least one electric sensor may be configured to detect a non-rotational and purely longitudinally sliding displacement of the first element relative to the second element.

With some examples the at least one electric sensor and the respective detector arrangement may be configured or may be operable to detect and/or to measure a longitudinal displacement as well as a rotational displacement of the first element relative to the second element. With some examples the detector arrangement and the at least one electric sensor may be operable to detect and/or to quantitatively measure a rotational displacement and/or a longitudinal displacement between the first element and the second element when the first element is subject to a helical motion relative to the second element.

The detector arrangement and the at least one electric sensor may be configured to measure a rotational displacement and a longitudinal displacement simultaneously. In this way a precision of the detection and measurement can be increased and an error rate of the detection and/or measurement can be decreased.

With a further example the at least one electric sensor is arranged on the first element or on the second element. When the electric sensor is arranged on the second element it may coincide with the reference element or it may constitute the reference element. When the electric sensor is arranged on the first element the at least one electric sensor is typically electrically connected to the pattern of the first element. Then and for detecting and/or measuring a relative displacement of the first element relative to the second element the pattern directly interacts with the reference element of the second element when the first and second elements are subject to at least one of the first movement and the second movement.

Arranging the at least one electric sensor and eventually even the entire detector arrangement on the first element allows and supports a rather easy, straight forward and smooth embedding or integration of the reference element into or on the second element. Here, the reference element may be a passive electronic device or passive electronic structure, such as a bridging contact.

With another example the first movement of the first element relative to the second element is a helical movement. The second movement is a longitudinal sliding movement of the first element relative to the second element during which the first element is rotationally locked to the second element.

With some examples of the injection device a longitudinal displacement of the first element relative to the second element during the first movement is equal in size to a longitudinal displacement of the first element relative to the second element during the second movement.

Typically, the longitudinal component of the first movement is opposite to the longitudinal component of the second movement. If the first element is moved in a longitudinal proximal direction during the first movement it will be moved in the opposite longitudinal direction, i.e. the distal direction during the second movement.

Typically, the longitudinal position of the first element relative to the second element before setting of a dose equals the longitudinal position of the first element relative to the second element after completion of a dose dispensing or dose expelling procedure.

A rotational position, hence a rotational state of the first element relative to the second element before setting of a dose may differ from a rotational state or rotational orientation of the first element relative to the second element after completion of the dose dispensing or dose expelling procedure. This is particularly the case in situations where the helical movement of the first element relative to the second element includes only a fraction of a revolution or a non integer multiple of a complete revolution of the first element relative to the second element.

With some examples the detector arrangement and the at least one electric sensor is operable to detect and/or to quantitatively measure at least one of the first movement and the second movement irrespective of an initial rotational state or rotational orientation of the first element relative to the second element. A movement detection may start and may end at any

conceivable and hence arbitrary rotational position or rotational orientation of the first element relative to the second element.

With some examples the first element and the second element are both of tubular shape. They may be either directly or indirectly mechanically engaged so as to follow a relative helical motion in one longitudinal direction and to follow a relative non-rotational sliding displacement along the other longitudinal direction. The first element and the second element may be arranged in a nested manner. One of the first and second elements may at least in sections circumferentially enclose or radially enclose the other one of the first and the second element.

With some examples the first element is subject to a helical motion along the longitudinal proximal direction relative to the second element for setting of a dose. Then, the first element is subject to a non-rotational sliding displacement relative to the second element along the distal longitudinal direction during dispensing of the dose. With other examples and for setting of the dose the first element is rotationally locked but axially displaceable relative to the second element, typically along the longitudinal proximal direction. For dispensing or expelling of the dose the second element may be subject to a helical motion relative to the second element in the distal direction.

In another example the pattern comprises at least a first pattern portion and a second pattern portion. First and second pattern portions are spatially non-overlapping pattern portions. Hence, the second pattern portion does not overlap with the first pattern portion. On the tubular-shaped surface of the first element, the first pattern portion and the second pattern portion are located next to or adjacent to each other. In this way, the first and the second pattern portions form a spatial pattern allowing to characterize and/or to quantify at least one of a rotational and a longitudinal movement of the pattern relative to the reference.

The at least one electric sensor is capable to distinguish between the first pattern portion and the second pattern portion. Every time one of the first and second pattern portions passes by the at least one electric sensor, the at least one electric sensor is operable to generate a processable electric signal, thus indicating that the pattern is currently subject to a movement relative to the reference element.

With another example the first pattern portion and the second pattern portion distinguish with regard to at least one of the following parameters: electrical conductivity, optical transmissivity, optical reflectivity, magnetic susceptibility or electric susceptibility. The first and second pattern portion may further distinguish by their radial position with regard to a central axis of the tubular shaped surface. For instance, the first and second patterns may be formed by protrusions or indentations, such as ridges and grooves on the tubular-shaped surface of the first element.

The at least one electric sensor is implemented in accordance to the distinguishing parameters of the first pattern portion and the second pattern portion. If the first and the second pattern portions distinguish by their electrical conductivity the at least one electric sensor is typically capable to measure the electrical conductivity of the pattern and of its respective first and second pattern portions. The at least one electric sensor may comprise at least one electrical contact tap that is configured and operable to get in electrical contact with only one of the first pattern portion and the second pattern portion at a time. Likewise and when the first and second pattern portions distinguish with regard to the optical transmissivity or optical reflectivity the at least one electric sensor typically comprises at least one of a light source and a light detector. Typically, the detector arrangement and the at least one electric sensor comprise a combination of a light source and a light detector, such as a light emitting diode LED and a photodiode.

Accordingly, and when first and second pattern portions distinguish by their magnetic susceptibility or electric susceptibility the at least one electric sensor comprises a respective magnet or dielectric sensor arrangement capable to distinguish between the first pattern portion and the second pattern portion of the pattern of the first element, wherein the first and the second pattern portions feature different magnetizations.

When the first pattern portion and the second pattern portion exhibit different radial positions with regard to a central axis of the tubular-shaped surface the at least one electric sensor may be implemented as a mechanical or electromechanical switch arranged at a predefined radial distance from the central axis. Here, the first and the second pattern portions may distinguish by their radial height. For instance, the first pattern portion may comprise an indentation or groove in the tubular-shaped surface and the second pattern portion may comprise at least one of a protrusion, rib or ridge protruding radially from the tubular-shaped surface of the first element.

As at least one of a protrusion or indentation passes by the at least one electric sensor, a respective electromechanically implemented switch may be activated or deactivated thus leading to the generation of a respective electric signal that can be processed for a movement detection and/or for a quantitative measurement of the size of at least one of the first movement and the second movement between the first and the second elements.

According to a further example a longitudinal extension of the pattern is equal to or larger than a maximum longitudinal displacement of the first member relative to the second member. In this way it is ensured, that the first pattern is and remains within a certain range of the reference element even if the first element is subject to a maximum longitudinal displacement relative to the second element. When the reference element is provided with the at least one electric sensor the pattern and the sensor cannot get out of contact or out of interaction even if the first element is subject to a maximum possible longitudinal movement relative to the second element. In this way and for each allowable longitudinal position of the first element relative to the second element at least one of the detector arrangement, the at least one electric sensor and the reference element is and remains in direct interaction with the pattern of the first element.

According to another example the pattern comprises a first pattern section and a second pattern section. The first pattern section and the second pattern section are arranged non-overlapping on the tubular-shaped surface. The second pattern section is separated from the first pattern section in longitudinal direction. In other words, the first pattern section may comprise or form a first longitudinal portion of the pattern and the second pattern section may comprise or form a second longitudinal pattern section non-overlapping with the first longitudinal pattern section.

At least one of the first and the second pattern sections comprises a first pattern portion and a second pattern portion as described above. Even both of the first and the second pattern sections may each comprise at least a first pattern portion and at least a second pattern portion.

For instance, the first pattern section may comprise a first sub-pattern. The second pattern section may comprise a second sub-pattern. First and second sub-patterns may be substantially equal. First and second pattern sections may substantially distinguish. The first and the second pattern section are typically separated in longitudinal direction on the tubular-shaped surface of the first element.

The first and the second pattern sections may serve different detection purposes. The first pattern section may comprise a longitudinal extension that is larger than a longitudinal extension of the second pattern section. Moreover, the second pattern section may be provided or located at an axial end of the first pattern section. The second pattern section may be encircled or surrounded by the first pattern section. With some examples the first pattern section is configured and operable to detect and/or to measure a rotational movement of the first element relative to the second element. The second pattern section may be configured to detect and/or to measure a longitudinal and hence non-rotational movement of the first element relative to the second element.

There may be provided at least one electric sensor to interact with at least one of the first pattern section and the second pattern section. There may be provided at least two electric sensors, one of which configured and operable to exclusively interact with the first pattern section and the other one of which being implemented and exclusively configured to interact with only the second pattern section.

Typically, a transition from the first pattern section towards the second pattern section along the longitudinal direction is detectable by the at least one electric sensor. In this way, the interaction between the least one electric sensor and the first and second pattern sections may serve to detect a particular longitudinal position of the first element relative to the second element, e.g. when the first element returns into an initial configuration or end-of-dose configuration with regard to the second element at the end of a dose dispensing or dose expelling procedure.

In another example the first pattern section comprises a stripe pattern comprising a number of parallel orientated longitudinal stripes. The longitudinal stripes extend parallel to the longitudinal direction. They may hence extend parallel to a central axis of the tubular-shaped surface of the first element. With another example the longitudinal stripes extend at a predefined non-zero angle with regard to the longitudinal direction.

With a stripe pattern comprising a number of parallel oriented longitudinal stripes extending parallel to the longitudinal direction the first pattern section is particularly dedicated and configured to determine and/or to measure a rotational movement of the first element relative to the second element. If the longitudinal stripes extend at a predefined angle with regard to the longitudinal direction, in other words, if the longitudinal stripes of the first pattern section are skewed or slanted with regard to the central axis not only a rotational displacement of the pattern and hence of the first element relative to the second element can be detected and quantitatively measured by means of the at least one electric sensor but also a non-rotating

longitudinal sliding movement of the first element relative to the second element can be detected and quantitatively measured, e.g. with only one and the same electric sensor.

The stripe pattern may comprise numerous stripes of equal or different geometry. The stripes may be equiangularly spaced along the circumference of the tubular-shaped surface. In accordance to an angular encoding the stripes of the stripe pattern may also be

heterogeneously distributed in tangential direction on the tubular-shaped surface. The stripes of the stripe pattern may also comprise different dimensions.

The position, size, shape and orientation of the stripes of the stripe pattern strongly depend on the specifically implemented encoding scheme. It depends on the number and on the position of the at least one electric sensor. With some examples the number, the size, the geometry and the orientation of the stripes depends on the number, the size and the position or orientation of bridging contacts provided on the second element.

According to a further example the detector arrangement is operable to detect a longitudinal overlapping of the reference element with at least one of the first pattern section and the second pattern section irrespective of a rotational state of the first element relative to the second element. A longitudinal overlapping means that the reference element and at least one of the first pattern section and the second pattern section are located at the same longitudinal position. Here, the reference element and at least one of the first pattern section and the second pattern section may overlap in radial direction with regard to the tubular shape of the pattern.

In particular, the detector arrangement and/or the at least one electric sensor is operable to detect a transition from the first pattern section to the second pattern section and vice versa. In other words, the detector arrangement is configured to detect when the first pattern section initially radially overlapping with the reference element is subject to a longitudinal displacement such that the second pattern section starts to radially overlap with the reference element. A separation or transition between the first and second pattern sections is detectable by the detector arrangement. In this way, a longitudinal or axial end position of the first element relative to the second element can be precisely detected thus indicating to the detector arrangement that e.g. a dose expelling procedure has been completed and that the injection device is in an initial state in which it is ready for a subsequent dose setting and dose injecting procedure.

Typically, the detector arrangement is operable and configured to detect a longitudinal sliding displacement of at least one of the first pattern section and the second pattern section relative to the reference element irrespective of a rotational state or rotational orientation of the first element relative to the second element. In effect and with any rotational position of the first element relative to the second element a longitudinal displacement or movement of the first element relative to the second element can be at least detected. In order to achieve such a detection the second pattern section may comprise a pattern or sub-pattern that differs in size and/or geometry from the pattern or sub-pattern of the first pattern section. For instance, the second pattern section may comprise an annular shape enabling a detection of a longitudinal sliding motion or screwing motion of the first element relative to the second element for any available rotational state or rotational orientation of the first element relative to the second element.

In a further example the pattern comprises at least a first pattern portion that is electrically conductive. The pattern comprises at least a second pattern portion that is electrically insulating. Typically, the pattern comprises numerous first pattern portions and numerous second pattern portions. For instance, the pattern comprises a sequence of electrically conductive portions and a sequence of electrically insulating portions. The electrically conductive pattern portions may be electrically separated or galvanically separated from each other through the electrically insulating second pattern portions.

The first pattern portion and the second pattern portion being electrically conductive and electrically insulating, respectively may correspond and represent the above mentioned first and second pattern portions of the pattern that are arranged non-overlapping with respect to each other and that distinguish with regard to their electrical conductivity.

The first and second pattern portions may be arranged alternately along at least one of the first movement and the second movement between the first and the second elements. The first and the second pattern portions may be separated along a circumference or along a tangential direction of the tubular-shaped surface of the first element. The first and the second pattern portions may also be separated along the longitudinal direction of the tubular-shaped surface. The first and the second pattern portions may comprise a stripe pattern with an alternating arrangement of stripes exhibiting at least two different electrical conductivities. The pattern is not limited to a first pattern section and to a second pattern section. There may be provided numerous different pattern sections, such as first, second, third or even more pattern sections that all distinguish from each other e.g. with regard to their electrical conductivity. In this way a higher information density or code density can be provided on the tubular-shaped surface.

With some examples the pattern is provided on an outside surface of the first element. With other examples the pattern is provided on an inside surface of the first element.

The pattern may comprise a binary pattern comprising an information content provided by at least two, namely first and second pattern portions representing a digital 0 or a digital 1 , respectively.

The pattern and the at least one electric sensor may be implemented as an incremental or as an absolute quadrature encoder. They may be implemented as a 2-bit gray code. Depending on the number of electric sensors or electric contact taps and depending on the specific implementation of the pattern also other codes, comprising a 3-bit encoding or an n-bit encoding with n being an integer number can be provided.

When the pattern comprises an electrically conductive structure, e.g. when the first pattern portion is electrically conductive it may comprise one of a conductive varnish, a conductive lacquer, a conductive coating or conductive etching. The conductive varnish or conductive lacquer may comprise electrically conductive particles, such as metal particles or carbon black particles. The electrically conductive pattern may also comprise a metal inlay in or on the tubular-shaped surface of the first element. The first element may comprise a thermoplastic material being substantially electrically insulating. In this way only the electrically conductive pattern portions have to be provided on the electrically insulating material of the first element. The electrically conductive first pattern portion may also comprise a sheet metal attached to or embedded in and flush with the tubular-shaped surface of the first element. The at least first electrically conductive pattern portion may be attached or assembled to the tubular-shaped surface by way of insert molding or by way of a two-component injection molding of the first element.

In a further example the detector arrangement comprises at least one electrical contact tap arranged on the second element and operable to alternately connect to the first pattern portion and the second pattern portion of the pattern when the first element is subject to one of the first movement and the second movement relative to the second element. The electrical contact tap may be radially biased so as to frictionally engage with the pattern of the first element. When the pattern is provided on an outer tubular-shaped surface of the first element the at least one electrical contact tap is biased radially inwardly. It is flexible or deformable radially outwardly by the pattern against an inherent restoring force.

When the tubular-shaped surface is an inner surface the at least one electrical contact tap is biased radially outwardly and can be deformed or flexed radially inwardly against a respective restoring force. The electrical contact tap may represent the reference element. Hence, the

reference element may comprise the at least one electrical contact tap. The reference element may comprise numerous electrical contact taps arranged and distributed along the outer or inner circumference of the tubular-shaped surface.

With another example the pattern comprises at least a third pattern portion that is electrically conductive, wherein the first pattern portion and the third pattern portion are electrically separated from each other. Hence, the first pattern portion and the third pattern portion are galvanically insulated from each other. The first pattern portion and the third pattern portion can be electrically separated by the second pattern portion that is electrically insulating. Providing at least two different types of electrically conductive pattern portions allows and supports implementation of an n-bit rotary encoder, with n being an integer equal to or larger than 2. When the first pattern portion and the third pattern portion are electrically distinguishable they can be individually and/or separately electrically connectable to the detector arrangement when subject to one of the first and second movement thus enabling e.g. a 3-bit rotary encoder.

With other examples the third pattern portion may be permanently electrically connected to a voltage supply of the detector arrangement. Here, the at least one electric sensor may be electrically connected to the first pattern portion. The rotary encoder may be completed by a bridging contact provided on the second element. The bridging contact may be configured and operable to selectively establish an electric connection between the third pattern portion and the first pattern portion as the first element is subject to a helical or rotational movement relative to the second element. With this example the second element can be void of any active electronic components. It may comprise only passive electrically conducting components, such as electric contact taps or at least one bridging contact.

In another example the detector arrangement and the at least one electric sensor are arranged on the first element. The at least one electric sensor is electrically connected to the first pattern portion. The at least one reference element is arranged on the second element and comprises an electrical bridging contact. The electrical bridging contact is configured to alternately establish and interrupt an electric contact between the first pattern portion and the third pattern portion when the first element is subject to one of the first movement and the second movement relative to the second element.

Typically, the electrical bridging contact extends in a tangential direction with regard to the tubular shape of the first element. The bridging contact may be implemented and operable to establish an electrical contact between the first pattern portion and the third pattern portion, e.g. thereby bridging the second pattern portion located between and/or separating the first pattern portion and the third pattern portion. This electric connection between the first pattern portion and the third pattern portion is typically provided when the first element is in a first rotational position or rotational orientation with regard to the second element. As the second element is subject to a further rotation and arrives at a second rotational state or rotational orientation at least one of the first pattern portion and the third pattern portion loses contact with the electrical bridging contact. In this way, the first pattern portion and the third pattern portion become electrically or galvanically separated.

Since the at least one electric sensor is electrically connected to the first pattern portion a varying electrical contact with the third pattern portion can be detected by the at least one electric sensor as the first element is subject to a rotation relative to the second element. Here, the third pattern portion may also be electrically connected to the at least one electric sensor or to another electric sensor of the detector arrangement. Alternatively, the third pattern portion may be permanently connected to a voltage supply of the detector arrangement. With rotational positions of the first and second elements, in which the first pattern portion is electrically connected to the third pattern portion via the at least one electrical bridging contact the first element is provided with the supply voltage. In other rotational states, wherein the first pattern portion is electrically separated from the third pattern portion the electric sensor connected to the first pattern portion will detect a zero voltage.

Use and implementation of at least one electrical bridging contact is beneficial because the second element can be easily adapted for the implementation and embedding of the detector arrangement. Here, only the geometry of the second element has to be slightly modified in order to receive or to assemble the at least one electrical bridging contact. Insofar, the second element does not require any active electric or electronic components but requires only a passive electrically conductive structure.

With another example the electrical bridging contact comprises a first electrical contact tap and a second electrical contact tap. The first electrical contact tap and the second electrical contact taps are electrically connected. The first electrical contact tap and the second electrical contact tap are spatially separated from each other along a first separation direction parallel to a distance between the first pattern portion and the third pattern portion. The magnitude of spatial separation between the first electrical contact tap and the second electrical contact tap is typically larger than a size or width of at least one of the first pattern portion and the third pattern portion as seen along the first separation direction.

Typically, the spatial separation between the first electrical contact tap and the second electrical contact tap is at least equal to or larger than the size or extension of the second pattern portion located between the first pattern portion and the third pattern portion as seen along the first separation direction. In this way it is ensured, that at least with one rotational state or rotational orientation of the first element relative to the second element the first pattern portion is electrically connected to the third pattern portion via the electrical bridging contact, namely when the first electrical contact tap is in electrical connection with the first pattern portion and the second electrical contact tap is in electrical connection with the third pattern portion.

With another example the first separation direction extends substantially parallel to an imaginary shortest connection between the first pattern portion and the third pattern portion. For instance, if the first and the second pattern portions are portions of a stripe pattern the first separation direction extends substantially perpendicular to the longitudinal extension of the stripes of the pattern.

According to a further example the electrical bridging contact comprises a third electrical contact tap spatially separated from at least one of the first electrical contact tap and the second electrical contact tap along a second separation direction that is non-parallel to the first separation direction. With some examples the second separation direction extends substantially perpendicular to the first separation direction. If the pattern on the first element comprises a longitudinal stripe pattern the first and second electrical contact taps are particularly configured to alternately engage or to alternately contact the alternating stripes as the first element is subject to a rotation or helical movement relative to the second element.

Typically, the first and the second electrical contact taps are only displaceable relative to the first element in the region of the first pattern section. Moreover, the first pattern section may be entirely provided with a stripe pattern comprising at least one first, second and at least one third pattern portion.

The third electrical contact tap of the electrical bridging contact may be located offset from at least one or from both of the first electrical contact tap and the second electrical contact tap along the longitudinal direction. In this way and as the first element is subject to a longitudinal displacement relative to the second element the third electrical contact tap may reach into or onto the second pattern section. The second pattern section may be separated from the first pattern section along the longitudinal direction. The second pattern section may be out of reach for the first and the second electrical contact taps of the electrical bridging contact but it may be engageable with only the third electrical contact tap of the electrical bridging contact. In this way the interaction of the third electrical bridging contact with the second pattern section may be an indicator that a longitudinal end position, e.g. a zero dose configuration or end-of-dose configuration of the injection device has been reached.

Accordingly and in another example the third bridging contact is configured to get in contact with the second pattern section when the first element and the second element return into an initial relative position after completion of the dispensing of the dose. In this way, the mutual engagement or contact between the third bridging contact and the second pattern section provides a zero dose indicator thus indicating to the detector arrangement, that the end of a dose dispensing or expelling procedure has been reached.

With further examples the injection device comprises two or more electrical bridging contacts that are distributed along the tubular circumference of the first element. The two or more electrical bridging contacts may be located at the same longitudinal position on the second element. They may be equiangularly or equidistantly arranged along the circumference or along the tangential direction of the tubular-shaped surface of the first element.

Typically, also the second element is of tubular shape. Accordingly, the two or more electrical bridging contacts can be separated from each other along the circumference or tangential direction of the tubular-shaped second element. The two or more electrical bridging contacts can be implemented identically. Hence, a first electrical bridging contact has the same shape and geometry compared to a second electrical bridging contact. The two or more electrical bridging contacts can be also asymmetrically arranged along the circumference of the second element. Hence, a distance or angular distance between a first and a second electrical bridging contact may differ from a distance or angular distance between the second and a third electrical bridging contact. The geometric arrangement of the two or more electrical bridging contacts depends on the encoding of the pattern on the first element.

With another example the two or more electrical bridging contacts and the first and the third pattern portions are arranged such, that in any available rotational position of the first element relative to the second element at least one of the first pattern portions is electrically connected to at least one of the third pattern portion via the at least one of the bridging contacts. In this way, at least one of the first pattern portions is at a supply voltage if the at least one third pattern portion is connected to a voltage supply. In this way, an unequivocal electrical signal can be provided for each available rotational position of the first element relative to the second element.

In another example the electrical bridging contact comprises a body made of sheet metal and further comprising at least one flexible arm. At least one of the first electrical contact tap and the second electrical contact tap is arranged at a free end of the at least one flexible arm. The electrical bridging contact may comprise numerous flexible arms, such as a first flexible arm, a second flexible arm and optionally also a third flexible arm. Typically, the first electrical contact tap is located at or on a free end of the first flexible arm of the electrical bridging contact. The second electrical contact tap is arranged or located at a free end of the second flexible arm of the electrical bridging contact. The same may be valid for an optional third electrical contact tap. Also the third electrical contact tap can be provided and arranged at or on a free end of a third flexible arm of the electrical bridging contact.

The electrical bridging contact can be fastened to or can be embedded in the second element. For instance, the electrical bridging contact is insert-molded in or on the second element, which may comprise an injection molded plastic component. Typically, the at least one flexible arm of the electrical bridging contact may be radially biased or pre-tensed towards the tubular-shaped surface of the first element. This ensures a non-interrupting mechanical contact between the at least one arm and/or of the respective electrical contact tap with the pattern on the tubular shaped surface.

The at least first electrical contact tap may protrude from the at least first flexible arm of the electrical bridging contact. It may comprise an embossed dome-shaped or spherical structure integrally formed in the sheet metal and protruding from the flexible arm towards the tubular shaped surface of the first element. The electrical bridging contact may be manufactured by metal pressing. It may comprise stainless steel. The electrical contact taps may comprise a dome-shaped embossed pin in the flexible arm exhibiting only a rather low degree of static or dynamic friction with regard to the pattern.

Claims

1. An injection device for setting and injecting pre-set or user-selectable doses of a medicament, the injection device comprising:

an elongated housing (10) defining a longitudinal direction (z) and configured to accommodate a cartridge (20) containing the medicament,

a detector arrangement (50) operable to detect a relative movement between a first element (100) and a second element (200), wherein the first element (100) is subject to a first movement relative to the second element (200) along a first longitudinal direction (3) for setting of a dose and wherein the first element (100) is subject to a second movement relative to the second element (200) along a second longitudinal direction (2) for dispensing of the dose, and wherein one of the first movement and the second movement is a helical movement and wherein the other one of the first movement and the second movement is a sliding movement in the longitudinal direction (z),

wherein the second element (200) comprises at least one reference element (60; 160) fixed to the second element (200),

wherein the first element (100) comprises a tubular shaped surface (102) provided with a pattern (104) facing towards the reference element (60; 160),

wherein the detector arrangement (50; 150) comprises at least one electric sensor (51 ; 151) arranged on one of the first element (100) and the second element (200) and being operable to detect a positional variation of the pattern (104) relative to the at least one reference element (60; 160) and to generate at least one electric signal in response to the positional variation of the pattern (104) during at least one of the first movement and the second movement of the first element (100) relative to the second element (200).

2. The injection device according to claim 1 , wherein the pattern (104) comprises at least a first pattern portion (110) and a second pattern portion (112) non-overlapping with the first pattern portion (110) and wherein the first pattern portion (110) and the second pattern portion (112) distinguish with regard to at least one of the following parameters: electrical conductivity, optical transmissivity, optical reflectivity, magnetic susceptibility, electric susceptibility and radial position with regard to a central axis of the tubular shaped surface (102).

3. The injection device according to any one of the preceding claims, wherein a longitudinal extension of the pattern (104) is equal to or larger than a maximum longitudinal displacement of the first member (100) relative to the second member (200).

4. The injection device according to any one of the preceding claims, wherein the pattern (104) comprises a first pattern section (120) and a second pattern section (122), wherein the first pattern section (120) and the second pattern section (122) are arranged non-overlapping on the tubular shaped surface (102) and wherein the second pattern section (122) is separated from the first pattern section (120) in longitudinal direction (z).

5. The injection device according to claim 4, wherein the first pattern section (120) comprises a stripe pattern (124) comprising a number of parallel oriented longitudinal stripes (126), wherein the longitudinal stripes (126) extend parallel to the longitudinal direction (z) or wherein the longitudinal stripes (126) extend at a predefined angle with regard to the

longitudinal direction (z).

6. The injection device according to claim 4 or 5, wherein the detector arrangement (50; 150) is operable to detect a longitudinal overlapping of the reference element (60; 160) with at least one of the first pattern section (120) and the second pattern section (122) irrespective of a rotational state of the first element (100) relative to the second element (200).

7. The injection device according to any one of the preceding claims, wherein the pattern (104) comprises at least a first pattern portion (110) that is electrically conductive and at least a second pattern portion (112) that is electrically insulating.

8. The injection device according to claim 7, wherein the detector arrangement (50; 150) comprises at least one electrical contact tap (52, 53, 54; 164, 166, 168) arranged on the second element (200) and operable to alternately connect to the first pattern portion (110) and the second pattern portion (112) of the pattern (104) when the first element (100) is subject to one of the first movement and second movement relative to the second element (200).

9. The injection device according to claim 7 or 8, wherein the pattern (104) comprises at least a third pattern portion (114) that is electrically conductive, wherein the first pattern portion (110) and the third pattern portion (114) are electrically separated.

10. The injection device according to claim 9, wherein the detector arrangement (150) and the at least one electric sensor (151) are arranged on the first element (100), wherein the at least one electric sensor (151) is electrically connected to the first pattern portion (110) and wherein the at least one reference element (160) is arranged on the second element (200) and comprises an electrical bridging contact (162) configured to alternately establish and interrupt an electric contact between the first pattern portion (110) and the third pattern portion (114) when the first element (104) is subject to one of the first movement and the second movement relative to the second element (200).

11. The injection device according to claim 10, wherein the electrical bridging contact (162) comprises a first electrical contact tap (164) and a second electrical contact tap (166), wherein the first electrical contact tap (164) and the second electrical contact tap (166) are electrically connected and wherein the first electrical contact tap (164) and the second electrical contact tap (166) are spatially separated from each other along a first separation direction (D1) parallel to a distance between the first pattern portion (110) and the third pattern portion (114).

12. The injection device according to claim 11 , wherein the electrical bridging contact (162) comprises a third electrical contact tap (168) spatially separated from at least one of the first electrical contact tap (164) and the second electrical contact tap (166) along a second separation direction (D2) non-parallel to the first separation direction (D1).

13. The injection device according to any one claim 10 to 12, wherein the electrical bridging contact (162) comprises a body (161) made of sheet-metal and comprising at least one flexible arm (163, 165, 167), wherein at least one of the first electrical contact tap (164) and the second electrical contact tap (166) is arranged at a free end of the at least one flexible arm (163, 155, 167).

14. The injection device according to any one of the preceding claim 8 to 13, further comprising at least one cleaning pad (210, 211 , 212, 213) arranged on or in the second element (200) at a distance from the at least one electrical contact tap (52, 53, 54; 164, 166, 168) along at least one of the first movement and the second movement.

15. The injection device according to any one of the preceding claims 10 to 13, wherein a length of a longitudinal movement of the first element (100) relative to the second element (200) during the first movement is identical to a length of a longitudinal movement of the first element (100) relative to the second element (200) during the second movement and wherein at least

one of the contact taps (164, 166, 168) is at a first rotational position relative to the pattern (104) before the first element (100) and the second element (200) are subject to the first movement, wherein when the helical movement of the first element (100) relative to the second element (200) during one of the first movement and the second movement comprises a non-integer multiple rotation of the first element (100) relative to the second element (200) the at least one of the contact taps (164, 166, 168) is at a second rotational position after a completion of the second movement, wherein the second rotational position differs from the first rotational position.