The present disclosure relates to an auto injector, such as an electronic auto injector, and a system comprising an auto injector and a cartridge for use with an auto injector.

BACKGROUND

Hypodermic syringes are widely used to deliver fluids to the body. It is known to have hypodermic syringes applicable for manual operation. However, auto injectors, which are becoming increasingly more advanced, have been developed and are widely used to aid the administering of fluid or medicaments to the body.

To avoid relying on users correctly performing certain tasks, it is of increasing interest that the auto injector automatically carries out as much as possible of the injection process.

It is generally known that air in a syringe should be depleted or minimized before injecting the medicament of the syringe. Injection of air may potentially cause problems such as air embolism. Thus, depletion or minimization of air in the syringe is usually performed before injecting the medicament.

Depletion of air is usually done by performing an air shot. An air shot is generally performed by pointing the syringe upwards, such that the air is near the opening of the syringe, and performing an expelling action until medication is expelled. Thereby the air is forced out of the syringe.

SUMMARY

There is a need for an auto injector, such as an electronic auto injector, with an improved capability of automatically performing an air shot.

The present disclosure provides a cartridge, such as a cartridge for an auto injector which is simple and therefore may be disposable, and an auto injector that may be usable for multiple injections. As it may be used multiple times, the auto injector may comprise more advanced features.

Accordingly, an auto injector is provided, such as an auto injector for administering injection of a medicament. The auto injector comprises a housing, a receiving part, an operational module, an orientation sensor, an optical sensor, and a processing unit. The receiving part is configured for receiving a syringe containing the medicament.

The operational module is configured for interacting with the syringe. The operational module is configured for moving a first stopper of the syringe at least in a first stopper direction. Thereby medicament may be expelled through a first syringe channel of the syringe and/or the medicament may be advanced towards the first end of the syringe, such as advanced through the first syringe channel.

The orientation sensor is configured to detect an orientation of the auto injector. The orientation of the auto injector is indicative of a corresponding orientation of the syringe. The orientation sensor is configured to provide an orientation sensor signal indicative of the orientation of the syringe and/or of the auto injector.

The optical sensor is configured to optically detect presence of medicament in the first syringe channel. The optical sensor is configured to provide an optical sensor signal indicative of presence of medicament in the first syringe channel.

The processing unit is configured to receive the orientation sensor signal and the optical sensor signal. The processing unit is configured to provide a control signal to the operational module based on the optical sensor signal and the orientation sensor signal. Also disclosed is a system comprising an auto injector and a syringe containing a medicament.

The syringe comprises a compartment configured for containing the medicament. The syringe has a first syringe end and a second syringe end. The syringe has a first syringe channel in fluid communication with the compartment at the first syringe end. The syringe comprises a first stopper movable inside the compartment at least in a first stopper direction from the second syringe end towards the first syringe end. The syringe is configured to expel medicament through the first syringe channel. The syringe may additionally or alternatively be configured for allowing the medicament to be advanced towards the first end of the syringe, such as advanced through the first syringe channel. The auto injector comprises a housing, a receiving part, an operational module, an orientation sensor, an optical sensor, and a processing unit.

The receiving part is configured for receiving the syringe.

The operational module is configured for interacting with the syringe. The operational module is configured for moving the first stopper at least in the first stopper direction. Thereby medicament may be expelled through a first syringe channel of the syringe and/or the medicament may be advanced towards the first end of the syringe, such as advanced through the first syringe channel. The stopper, or the piston, may be manufactured in a flexible material, such as rubber.

The orientation sensor is configured to detect an orientation of the auto injector. The orientation of the auto injector is indicative of a corresponding orientation of the syringe. The orientation sensor is configured to provide an orientation sensor signal indicative of the orientation of the syringe and/or of the auto injector.

The optical sensor is configured to optically detect presence of medicament in the first syringe channel. The optical sensor is configured to provide an optical sensor signal indicative of presence of medicament in the first syringe channel.

The processing unit is configured to receive the orientation sensor signal and the optical sensor signal. The processing unit is configured to provide a control signal to the operational module based on the optical sensor signal and the orientation sensor signal.

It is envisaged that any embodiments or elements as described in connection with any one aspect may be used with any other aspects or embodiments, mutatis mutandis. For example, the auto injector disclosed in relation to the system may be the auto injector as also disclosed.

The receiving part of the auto injector may be configured for receiving a cartridge comprising the syringe. The system may comprise a cartridge comprising the syringe. It is an advantage of the present disclosure that the procedure of performing an air shot may be performed automatically by the auto injector.

It is a further advantage of the present disclosure that the air shot may be performed without expelling medicament through the tip of the needle, such as a needle of the syringe and/or a needle attached to the syringe. In some embodiments, it may be important or desired, that dosages are known accurately. Hence, it may be desirable that the amount of medicament in the syringe is fully injected into the patient and it is therefore an advantage that the airshot may be performed automatically, and without expelling medicament through the tip of the needle.

Furthermore, medicament on the tip of a needle may provide patient discomfort upon insertion of the needle. And, especially for some medicaments, it may be undesirable to spill medicament, e.g. on the floor. It is thus a further advantage of performing the air shot without expelling medicament from the tip of the needle that patient discomfort may be reduced. It is thus advantageous that the present disclosure increases, dosage accuracy, decreases patient discomfort, and/or avoids spilled medicament.

The syringe comprises a compartment configured for containing the medicament. The syringe has a first syringe end and a second syringe end. The syringe has a syringe opening for fluid communication with the compartment at the first syringe end. A stopper, such as the first stopper, may limit the compartment in the second end whereas the compartment in the first end may be limited by the syringe opening. Thus, the compartment may be confined by compartment walls of the syringe, the stopper, such as the first stopper, and the syringe opening.

The compartment of the syringe may contain the medicament. The medicament may be a fluid and/or a liquid. The medicament may be an aqueous solution, e.g. saline. The medicament may comprise a first medicament component and/or a second medicament component. The compartment may contain the first medicament component and the second medicament component.

The syringe may be a multi chamber syringe, e.g. the compartment of the syringe may comprise a plurality of compartment parts. For example, the syringe may be a dual chamber syringe, e.g. the compartment of the syringe may comprise a first compartment part and a second compartment part. The first compartment part may contain the first medicament component. The second compartment part may contain the second medicament component.

Compartment parts may be divided by a stopper, such as a second stopper and/or a third stopper. For example, the syringe may comprise a second stopper between the first syringe end and the first stopper. The second stopper may divide the compartment into a first compartment part and a second compartment part. The second stopper may be movable inside the compartment, e.g. at least in the first stopper direction, such as along the stopper axis.

The compartment may comprise one or more bypass sections, such as a middle bypass section and/or a front bypass section. Bypass sections may provide fluid communication between compartment parts when a stopper is positioned in the bypass section. For example, when the second stopper is positioned in the middle bypass section, the first compartment part may be in fluid communication with the second compartment part.

In some embodiments, the first medicament component and the second medicament component may not need to be physically separated. Thus, providing a plurality of medicament components does not require the compartment to be divided into a plurality of compartment parts.

The first medicament component and/or the second medicament component may be a powder composition. The first medicament component and/or the second medicament component may be a fluid composition, such as a liquid composition. The first medicament component may be a powder composition and the second medicament component may be a fluid composition, e.g. water or ethanol. The first medicament component may be a solute. The second medicament component may be a solvent.

The present device is generally useful for administration of a medicament which is injected as a suspension. The medicament may be provided in the syringe as a suspension and/or the medicament may be provided in the syringe as a plurality of medicament components, such as a first medicament component and a second medicament component. A suspension may be obtained by mixing of the first component and the second component, e.g. by a first operation of the operational module, performed before injection.

The medicament may be a suspension, e.g. a liquid, such as water or an aqueous solution, comprising solid particles of one or more compound(s). The solid particles may be evenly distributed in the liquid. When a medicament is administered as a suspension, the solid particles typically comprise the active ingredient of the medicament, or the main part of the active ingredient. The risk of tissue damage on injection or injection site pain depends on factors, such as the choice of active ingredient and particle size. The mean particle size of the active ingredient (or other non-dissolved components) can be below 100 μΜ, such as 0.5 μιη - 100 μιη, such as 0.5 μιη - 50 μιη, such as 1 μιη - 10 μιη. "mean particle size" refers to volume mean diameter as may be measured by laser-light scattering methods (LLS). Particle size may be measured by LLS methods and mean particle size may be calculated from the particle size distribution. Suspensions can be prepared from a poorly soluble compound and/or compounds, e.g. a compound with solubility below 0.1 mg/ml in the liquid.

The medicament or an active ingredient of the medicament may comprise a poorly soluble medicament component, such as a medicament component having solubility in the solvent of less than 0.1 mg/ml.

A reusable auto injector, such as the disclosed auto injector, may be especially useful when the syringe comprises more than one compartment or more than one chamber. For example an auto injector for a multi compartment or multi chamber syringe may be more advanced, and therefore it may be beneficial to allow the auto injector to be used more than one time. For example, the auto injector may provide automated processes for mixing medicament components, such as for mixing medicament components initially provided in different compartments of the syringe.

The auto injector may be configured for specific medication and/or specific patients. The auto injector may provide increased possibility for injecting the medicament in certain patients, such as in schizophrenic patients.

The auto injector comprises a housing, a receiving part, an operational module, an orientation sensor, an optical sensor, and a processing unit.

The operational module of the auto injector may be configured for interacting with the cartridge and/or the syringe of the cartridge, such as when the cartridge and/or syringe are received in the receiving part of the auto injector. The operational module may be configured for moving a stopper of the syringe, e.g. the first stopper of the syringe, and/or the operational module may be configured for moving the syringe, e.g. relative to the main body. The operational module may be configured for moving the first stopper at least in the first stopper direction, e.g. to expel medicament through the syringe opening, and/or to advance the medicament towards the first end of the syringe.

The operational module may comprise a stopper operational part. The stopper operational part may be configured for moving a stopper, such as the first stopper. The stopper operational part may be configured for moving the first stopper at least in the first stopper direction, e.g. to expel medicament through the syringe opening, and/or to advance the medicament towards the first end of the syringe. The stopper operational part may comprise a plunger rod.

A plunger rod is throughout the present disclosure to be understood as any means capable of moving a stopper of a syringe in a first and/or second direction. The plunger rod may form part of an auto injector.

The operational module may comprise a syringe operational part. The syringe operational part may be configured for moving the syringe, e.g. along the tube axis.

The syringe operational part may be configured for moving a carrier of the operational module. The carrier of the operational module may be attachable to the syringe. The syringe operational part may be configured for moving the syringe to advance a needle of the syringe and/or attached to the syringe, e.g. to insert the needle into tissue of the patient. Alternatively or additionally, the syringe operational part may be configured for moving the syringe to mix a plurality of medicament components, e.g. to obtain a mixed medicament. For example, the syringe operational part may be configured for moving the syringe to mix the first medicament component and the second medicament component to obtain the mixed medicament. In some embodiments, the syringe operational part may be configured to mix the first medicament and the second medicament, after an operation of the stopper operational part has allowed the first medicament and the second medicament component into a same syringe

compartment.

The operational module may comprise a driver and/or a plurality of drivers, such as a stopper driver and/or a syringe driver. The driver(s) may be configured to drive one or more operational part(s) of the operational module. For example, the stopper driver may be configured to drive the stopper operational part and/or the syringe driver may be configured to drive the syringe operational part.

The operational module may comprise an electrical motor. The driver(s), such as the stopper driver and/or the syringe driver, may be a motor, such as an electromechanical motor and/or an electrical motor, such as a DC motor, e.g. a DC motor with or without brushes. For example, the stopper driver may be a brushed DC motor and/or the syringe driver may be a brushless DC motor. A brushless DC motor may be preferred due to higher durability of a brushless DC motor. Especially for the syringe driver a brushless DC motor may be preferred due to many and/or rapid movements performed by the syringe driver. Brushed DC motors are generally cheaper than brushless DC motors. Therefore brushed DC motors may be preferred from a cost perspective. A brushed DC motor may be preferred for the stopper driver.

The auto injector comprises a processing unit. The processing unit may be connected to the operational module. The processing unit may be configured to operate the operational module, such as the syringe operational part and/or the stopper operational part and/or the stopper driver and/or the syringe driver.

The processing unit is configured to provide a control signal to the operational module, such as to the syringe operational part and/or to the stopper operational part and/or to the stopper driver and/or to the syringe driver.

The control signal may be configured to cause the operational module to move the first stopper. The control signal may be configured to cause a desired operation of the operational module. The processing unit may configure the control signal, e.g. in accordance with a desired operation of the operational module. For example, the control signal may be configured to cause the operational module to move the first stopper in the first stopper direction if the optical sensor signal indicates that medicament is not present in the first syringe channel and the orientation sensor signal indicates that the syringe has a predetermined orientation. Alternatively or additionally, the control signal may be configured to cause the operational module to stop movement of the first stopper if the optical sensor signal indicates that medicament is present in the first syringe channel. Alternatively or additionally, the control signal may be configured to cause the operational module to stop movement of the first stopper if the orientation sensor signal indicates that the syringe is not in a predetermined orientation.

It is an advantage of the present disclosure that the operational module may be controlled precisely by the processing unit, so that also the movement of at least the first stopper may be controlled precisely and that expelling of medicament through the tip of the needle may thereby be avoided.

The operational module, and/or the stopper operational part of the operational module, may be configured to operate in a plurality of modes, such as in a first operational mode and/or a second operational mode. In the first operational mode the operational module and/or the stopper operational part may be configured to move the first stopper with a first rate of movement. In the second operational mode the operational module and/or the stopper operational part may be configured to move the first stopper with a second rate of movement. The second rate of movement may be slower than the first rate of movement. For example, the operational module, and/or the stopper operational part, may be configured to operate at least in a first operational mode and a second operational mode to move the first stopper in a first mode and a second mode, the rate of movement being decreased in the second mode.

The first stopper movement may be initiated by activation of the operational module, such as by activation of the stopper operational part, such as by activation of the stopper driver. The movement of the first stopper may be stopped and/or discontinued by de-activating the operational module, such as by de-activating the stopper operational part, such as by de-activating the stopper driver.

The operational module and/or the stopper operational part and/or the stopper driver may have a maximum threshold. The operational module may be configured to stop movement of the first stopper when the maximum threshold is reached. The maximum threshold may designate a threshold where it is known that the air shot will be completed. The maximum threshold may be indicative of a certain distance of movement for the first stopper and/or the plunger rod. The maximum threshold may be determined according to a time factor, a movement factor, and/or an operational module factor, such as an operational module movement factor. For example, the maximum threshold may be determined to have been reached when the operational module and/or the stopper operational part and/or the stopper driver has been activated for a certain duration of time, i.e. a time factor. Alternatively or additionally, the maximum threshold may be determined to have been reached when the plunger rod and/or the first stopper is in a certain position, and/or when the plunger rod and/or the first stopper has moved a distance, such as a predetermined distance.

The auto injector comprises an orientation sensor. The orientation sensor may be configured to detect an orientation of the syringe and/or an orientation indicative of the orientation of the syringe, such as an orientation of the auto injector. The orientation sensor may be configured to detect the direction of gravity, and/or if the direction of gravity is within a certain range of a predetermined direction. The orientation sensor may be an accelerometer. The orientation sensor may comprise a tilt sensor, a tri-axial accelerometer, a single axis accelerometer, a magnetometer and/or any combination thereof, and the orientation sensor may provide a measure of roll, pitch and azimuth, a measure of acceleration and/or tilt in one or more directions.

The orientation sensor may be configured to detect if syringe is in a predetermined orientation. The orientation sensor may be configured to detect if the orientation of the auto injector is indicative of the syringe being in the predetermined orientation. The predetermined orientation may be a vertical orientation. The predetermined orientation may be an orientation within 45 degrees of vertical. The predetermined orientation may be an orientation wherein the syringe is orientated such that a syringe axis between the first syringe end of the syringe and the second syringe end of the syringe is within 45 degrees of vertical and the first syringe channel of the syringe is above the

compartment of the syringe, such as in a vertical position above the compartment of the syringe, the compartment containing the medicament. The predetermined orientation may be a vertical orientation. The predetermined orientation may be an orientation within 45 degrees of vertical.

The auto injector comprises an optical sensor. The optical sensor is configured to detect presence of medicament in the first syringe channel. The optical sensor may be calibrated and/or positioned such that when the optical sensor detects presence of medicament in the first syringe channel, the amount of air in the first syringe channel is less than a certain air threshold, e.g. less than 1 ml, such as less than 0.5 ml, such as between 0 and 0.3 ml, such as between 0.1 and 0.3 ml. For example, the optical sensor may be configured to detect presence of medicament in the first syringe channel such that air in the first syringe channel is between 0 and 0.3 ml when presence of medicament in the first syringe channel is detected. The first syringe channel may include a needle of the syringe and/or a needle attached to the syringe. The amount of air in the first syringe channel may include air in the needle of the syringe and/or in the needle attached to the syringe.

The optical sensor may be any sensor capable of measuring electromagnetic radiation, and in particular to measure and/or determined changes in electromagnetic radiation in response to the medicament being present in the first syringe channel. The optical sensor may measure electromagnetic radiation transmitted, reflected, refracted, and/or dispersed by the first syringe channel and/or by any medicament present in the first syringe channel.

The first syringe channel may be transparent and/or partly transparent, such as transparent and/or partly transparent to the electromagnetic radiation for which the sensor is configured, such as to light, such as visible light and/or infrared light and/or ultraviolet light.

The optical sensor may comprise a transmitting element, such as an electromagnetic radiation transmitter or a light transmitter and a receiving element, such as an electromagnetic radiation receiver or detector, a light receiver or a light detector.

Typically, the transmitting element comprises an emitting element, and is configured to transmit electromagnetic radiation or light towards the first syringe channel. Typically, the receiving element is configured to receive electromagnetic radiation or light refracted or reflected by the first syringe channel and/or any medicament present in the first syringe channel, or electromagnetic radiation or light transmitted through the first syringe channel and/or any medicament present in the first syringe channel. The light transmitter and the light receiver may be positioned on the same side of the first syringe channel. The light receiver may be configured to detect the light transmitted by the light transmitter and reflected by the media in the first syringe channel.

Alternatively, the light transmitter and the light receiver may be positioned on different sides of the first syringe channel. The light receiver may be configured to detect the light transmitted by the light transmitter and not obstructed by the media in the first syringe channel. The media in the first syringe channel may for example be air and/or the medicament.

The optical sensor may be any type of optical sensor including any electro-optical sensors and may comprise light-emitting-diodes, solid state optical sensors, photo diodes, photo detectors, etc.

The optical sensor may be configured to detect media having a reflection coefficient larger than a threshold, e.g. larger than the reflection coefficient of water. The optical sensor may be configured to optically detect presence of medicament in the first syringe channel by detecting media having a reflection coefficient larger than the reflection coefficient of water in the first syringe channel. The optical sensor may be configured to detect a white reflecting media.

The optical sensor and/or the light transmitter may be configured to transmit light such as visible light and/or infrared light and/or ultraviolet light.

The optical sensor and/or the light receiver may be configured to receive and/or detect light such as visible light and/or infrared light and/or ultraviolet light.

The auto injector may comprise a plurality of optical sensors. The optical sensor may be a first optical sensor and/or a second optical sensor and/or a third optical sensor of the plurality of optical sensors. Thus, the optical sensor may comprise a plurality of transmitter-receiver pairs. It is envisaged that in some embodiments, the transmitter and the receiver may be a combined transmitter and receiver.

The optical sensor may furthermore be configured to detect a change in received electromagnetic radiation or light in response to the presence of medicament in the first syringe channel. Typically, the syringe is in a retracted position, such as a retracted locked position, when the air shot is performed.

A user of the present disclosure may be a health care provider and/or a patient. There may be a plurality of users of the present disclosure, such as a first user and/or a second user and/or a third user. A patient may be a user of the device, e.g. the first user and/or the third user. A health care provider may be a user of the device, e.g. the second user.

The first syringe channel may comprise a part of the first end of the syringe, at least a part of the needle hub, a part of the needle and/or any combination thereof. The first syringe channel may thus be a needle hub, a needle attachment site, a tip of the syringe, and/or a part of a needle of the syringe. Typically, the optical sensor is positioned so that the medicament is detected at a threshold position of the first syringe channel. The threshold position being determined so that if medicament is detected and thus present at the threshold position, the amount of air in the first syringe channel is less than a certain air threshold. Typically, the first syringe channel comprises the needle hub.

In some embodiments the syringe may be manufactured with an attached needle. For example, the needle may be fixedly attached to the syringe. In other embodiments the syringe and the needle may be manufactured separately, and the user, e.g. a health care provider, may attach a needle to the syringe before use. The needle, such as a needle attached to the syringe, may form part of the first syringe channel. A needle hub of the needle, such as a needle attached to the syringe, may form part of the first syringe channel.

Some embodiments of the present disclosure may include shapes which are not circular. Unless otherwise indicated, a "diameter" of a non-circular shape is the greatest distance between two points on the boundary of the shape. Likewise, reference to the "inscribed diameter" will indicate the least distance between two points on the boundary of the shape.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present invention will become readily apparent to those skilled in the art by the following detailed description of exemplary embodiments thereof with reference to the attached drawings, in which:

Fig. 1 schematically illustrates an exemplary auto injector,

Fig. 2 schematically illustrates an exemplary optical sensor and part of a syringe,

Fig. 3 a-d schematically illustrates a step by step procedure of performing an air shot,

Fig. 4 schematically illustrates an exemplary system,

Fig. 5 schematically illustrates an exemplary syringe,

Fig. 6 schematically illustrates an exemplary operational module,

Fig. 7 shows a flow diagram of an exemplary method,

Fig. 8 shows a flow diagram of an exemplary method, and

Fig. 9 schematically illustrates an exemplary system DETAILED DESCRIPTION

Various embodiments are described hereinafter with reference to the figures. Like reference numerals refer to like elements throughout. Like elements will, thus, not be described in detail with respect to the description of each figure. It should also be noted that the figures are only intended to facilitate the description of the embodiments. They are not intended as an exhaustive description of the claimed invention or as a limitation on the scope of the claimed invention. In addition, an illustrated embodiment needs not have all the aspects or advantages shown. An aspect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiments even if not so illustrated, or if not so explicitly described.

Throughout, the same reference numerals are used for identical or corresponding parts.

Fig. 1 schematically illustrates an exemplary auto injector 300, such as an auto injector for administering injection of a medicament. The auto injector 300 comprises a housing 302, a receiving part 304, an operational module 306, an orientation sensor 332, an optical sensor 336, and a processing unit 330.

The receiving part 304 is configured for receiving a syringe containing the medicament. The receiving part 304 may be configured for receiving a cartridge comprising the syringe.

The operational module 306 is configured for interacting with the syringe and/or the cartridge, e.g. when the syringe and/or the cartridge are received in the receiving part 304. The operational module 306 is configured for moving a first stopper of the syringe at least in a first stopper direction, to thereby expel medicament through a first syringe channel of the syringe and/or advance the medicament towards the first end of the syringe. The syringe may comprise a second stopper and/or a third stopper, and the operational module 306 may be configured for moving the second stopper and/or the third stopper, e.g. to combine medicaments provided in different syringe compartments and/or to expel medicament through the first syringe channel. The first syringe channel may be a needle hub, a needle attachment site, a tip of the syringe, and/or a part of a needle of the syringe. The orientation sensor 332 is configured to detect an orientation of the auto injector 300 indicative of a corresponding orientation of the syringe, e.g. when the syringe and/or the cartridge are received in the receiving part 304. The orientation sensor 332 provides an orientation sensor signal 332 indicative of the orientation of the syringe and/or the cartridge and/or the auto injector 300. The orientation sensor 332 may be a gravitational sensor and/or an accelerometer and/or a magnetometer. The orientation sensor 332 may be configured to detect the orientation of the auto injector 300 and/or the syringe and/or the cartridge relative to gravitation, e.g. gravitational force.

The optical sensor 336 is configured to optically detect presence of a substance, such as a medicament, in the first syringe channel of the syringe, e.g. when the syringe and/or the cartridge are received in the receiving part 304. The optical sensor 336 provides an optical sensor signal 338 indicative of the presence of substance, e.g. medicament, in the first syringe channel.

The processing unit 330 is configured to receive the orientation sensor signal 334 and the optical sensor signal 338. The processing unit 330 is configured to provide a control signal 340 to the operational module 306 based on the optical sensor signal 338 and the orientation sensor signal 334.

For example, the control signal 340 may be configured to cause the operational module 306 to move the first stopper in the first stopper direction if the optical sensor signal 338 indicates that medicament is not present in the first syringe channel and the orientation sensor signal 334 indicates that the syringe and/or the cartridge and/or the auto injector has a predetermined orientation. Alternatively or additionally, the control signal 340 may be configured to cause the operational module to stop movement of the first stopper if the optical sensor signal 338 indicates that substance, e.g. medicament, is present in the first syringe channel. Alternatively or additionally, the control signal 340 may be configured to cause the operational module to stop movement of the first stopper if the optical sensor signal 334 indicates that the syringe and/or the cartridge and/or the auto injector does not have the predetermined orientation.

The predetermined orientation may be selected such that possible air in the syringe is displaced to a position such that the air is expelled before expelling medicament. For example, the predetermined orientation may be an orientation wherein the first syringe channel is pointing upwards, and/or within +/- 45 degrees of upwards. For example, the predetermined orientation may be an orientation wherein a syringe axis between a first syringe end of the syringe and a second syringe end of the syringe is within +/- 45 degrees of vertical, and/or such that the first syringe channel is in a vertical position above a compartment of the syringe, the compartment containing the medicament.

Control of the operational module 306 may comprise activation and/or deactivation of the operational module 306. Movement of the first stopper in the first stopper direction may be initiated by activation of the operational module 306. Movement of the first stopper may be stopped or discontinued by deactivating the operational module 306. For example, the operational module 306 may comprise an electric motor, such as a DC motor, and the operational module may be activated by providing current to the operational module 306, and the operational module 306 may be deactivated by not providing current to the operational module 306. The control signal 340 may be a DC signal.

The operational module 306 may be controlled by the processing unit 330 to move according to the following logic based on the optical sensor signal 338 and the orientation sensor signal 334:

Syringe has predetermined orientation + Medicament ]s in the first syringe channel

Stop movement of the first stopper

Syringe does not have predetermined orientation + Medicament ]s in the first syringe channel

Stop movement of the first stopper

Syringe does not have predetermined orientation + Medicament is not in the first syringe channel

Stop movement of the first stopper

Syringe has predetermined orientation + Medicament is not in the first syringe channel Start/continue movement of the first stopper

Fig. 2 schematically illustrates an exemplary optical sensor 336 and part of a syringe 100. The optical sensor 336 may be comprised in an auto injector, and the syringe 100 may be received in a receiving part of the auto injector. The auto injector may be configured to arrange the syringe 100 relative to the optical sensor 336 such that the optical sensor 336 is able to detect substance, such as medicament in a first syringe channel 1 10 of the syringe 100.

The syringe 100 comprises a compartment 102. The compartment 102 is configured for containing a medicament. The syringe has a first syringe end 104 and a second syringe end (not visible). A needle 1 16 having a needle tip 124 is attached to the syringe 100. The needle 1 16 may be attached to the syringe 100. Alternatively, the needle 1 16 may form a part of the syringe 100. The syringe has a first syringe channel 1 10 at the first syringe end 104. The first syringe channel 1 10 is in fluid communication with the compartment 102. The syringe 100 is configured to expel medicament, e.g. from the compartment 102, through the first syringe channel 1 10. The first syringe channel 1 10 may form part of the needle 1 16, e.g. the first syringe channel 1 10 may extend to the needle tip 124. In some embodiments, the first syringe channel forms part of the syringe without extending to the needle.

The optical sensor 336 is configured to detect substance, such as medicament in the first syringe channel 1 10 of the syringe 100. The optical sensor comprises a light transmitter 360 and a light receiver 362. The optical sensor 336 is configured to transmit light from the light transmitter 360, and measure the light reflected from the substance in the first syringe channel 1 10 by the light receiver 362. The optical sensor 336 and/or the light transmitter 360 and/or the light receiver 362 may be configured to transmit/receive light such as visible light, infrared light, and/or ultraviolet light. The reflection measured by the optical sensor 336, e.g. by the light receiver 362, indicates the substance in the first syringe channel 1 10. For example, the optical sensor 336 may be configured to detect a certain medicament having a certain reflection coefficient. Alternatively or additionally, the optical sensor 336 may be configured to detect a reflection coefficient different from air and/or water. The optical sensor 336 may be configured to optically detect presence of medicament in the first syringe channel 1 10 by detecting substance having a reflection coefficient larger than the reflection coefficient of water and/or air in the first syringe channel 1 10. The optical sensor 336 and/or the auto injector comprising the optical sensor 336 may be configured, e.g. the optical sensor 336 may be positioned relative to the first syringe channel 1 10, such that upon detection of medicament present in the first syringe channel 1 10, residual air in the first syringe channel 1 10 and/or in the needle 1 16 is less than 0.3 ml, such as less than 0.2 ml, such as less than 0.15 ml, such as less than 0.1 ml, and/or between 0 and 0.3 ml, such as between 0.1 and 0.3 ml.

Figs. 3a-d schematically illustrates a step by step procedure of performing an air shot, e.g. using an auto injector comprising an optical sensor configured to detect presence of medicament in a first syringe channel 1 10. Figs. 3a-d schematically illustrates an exemplary syringe 100 comprising a compartment 102 configured for containing a medicament 126. The syringe 100 has a first syringe channel 1 10 in fluid

communication with the compartment 102 at a first syringe end 104. The syringe 100 comprises a first stopper 1 12 movable inside the compartment 102 at least in a first stopper direction 502 from a second syringe end 106 towards the first syringe end 104. The syringe 100 is configured to expel medicament 126 through the first syringe channel 1 10.

Fig. 3a illustrates an initial situation that the compartment 102 contains an amount of air. The syringe 100 has been orientated, such that the air is displaced to the top of the compartment 102 near the first syringe end 104 and the medicament 126 is due to gravity displaced to the bottom of the compartment 102 near the first stopper 1 12 and/or distant from the first syringe channel 1 10. The orientation of the syringe 100 may be detected using an orientation sensor as described above. At this point, the first syringe channel 1 10 does not contain medicament 126. The presence of medicament in the first syringe channel 1 10 may be detected using an optical sensor as described above.

When the syringe 100 is in the predetermined orientation, and no medicament is in the first syringe channel 1 10 the first stopper 1 12 is moved in the first stopper direction

502. At this point it may be assumed that a certain minimum displacement of the first stopper 1 12 is necessary in order to perform the air shot. Therefore, the first stopper 1 12 may be moved an initial distance before detection of medicament 126 in the first syringe channel 1 10 is initiated. For example, it may be known that the air shot require a minimum displacement of the first stopper 1 12 of 52 mm, and a maximum displacement of the first stopper 1 12 of 54 mm. Thus, the first stopper 1 12 may always be moved 52 mm. The initial displacement may be performed by moving the first stopper 1 12 with a first rate of movement e.g. 3-5 mm per second. Fig. 3b illustrates a situation wherein the first stopper 1 12 has moved an initial distance, e.g. 52 mm. The first syringe channel 1 10 does not contain medicament 126. At this point, the movement of the first stopper 1 12 may be decreased to allow detection of medicament 126 in the first syringe channel 1 10. From this point the first stopper 1 12 may be moved with a second rate of movement, e.g. 0.5-1 .0 mm per second.

An auto injector with an operational module performing the movement of the first stopper 1 12 may be configured to operate in a first operational mode wherein the first stopper 1 12 is moved with the first rate of movement. The auto injector may further be configured to operate in a second operational mode wherein the rate of movement is decreased, such as decreased relative to the first rate of movement. In the second operational mode, the first stopper 1 12 may be moved with the second rate of movement. The second rate of movement may be slower than the first rate of movement.

Fig. 3c illustrates a situation wherein the first stopper 1 12 has moved a further distance compared to the situation in Fig. 3b. The medicament 126 enters the first syringe channel 1 10. However, the medicament 126 has not yet entered the needle 1 16. At this point, the medicament 126 may be detected in the first syringe channel 110 and movement of the first stopper 1 12 may be stopped or discontinued. The air shot may be termed complete, e.g. air in the first syringe channel 1 10 and/or in the needle amounts to less than a given threshold, e.g. less than 0.3 ml.

Fig. 3d illustrates a situation wherein the first stopper 1 12 has not been stopped and instead has moved a further distance compared to the situation in Fig. 3c. The medicament 126 has entered the needle 1 16 and medicament 126 is expelled from the needle tip 124. This situation may be undesired, since the medicament 126 at the needle tip 124 may present patient discomfort, and the dosage may be less precise as a small amount of medicament 126 is lost before injecting into the patient. However, it may be assumed that a certain maximum displacement of the first stopper 1 12 is necessary in order to perform the air shot. Therefore, movement of the first stopper 1 12 may be stopped when the maximum displacement has been reached. For example, it may be known that the air shot require a minimum displacement of the first stopper 1 12 of 52 mm, and a maximum displacement of the first stopper 1 12 of 54 mm. Thus, movement of the first stopper 1 12 may be stopped if it has moved 54 mm. An auto injector with an operational module performing the movement of the first stopper 1 12 may be configured to stop movement of the first stopper 1 12 if the first stopper 1 12 has been moved the maximum displacement.

Fig. 4 schematically illustrates an exemplary system 400 comprising an auto injector 300 and a cartridge 200 comprising a syringe 100 containing a medicament. The cartridge 200 is configured to be received in the auto injector 300, and the auto injector 300 is configured for administering injection of the medicament contained in the syringe 100 of the cartridge 200. The auto injector 300 may be used multiple times. The cartridge 200 may be discarded after use, e.g. after each use, and a new cartridge 200 may be inserted into the auto injector for a subsequent use.

The auto injector 300 comprises a housing 302 and a receiving part 304 configured for receiving the cartridge 200 and/or the syringe 100. The auto injector 300 furthermore comprises an operational module (not visible) configured for interacting with the cartridge 200. The operational module may be enclosed in the housing 302.

The cartridge 200 comprises the syringe 100 and a syringe casing 2 attached to the syringe 100. The syringe casing 2 comprises a main body 4. The main body 4 has a tube part 6 and a front end 10. The tube part 6 and/or the main body 4 may be transparent, or partly transparent, such that an optical sensor of the auto injector 300 may detect substance in a first syringe channel of the syringe 100 when the cartridge 200 is received in the receiving part 304 of the auto injector 300.

The tube part 6 extends along a tube axis 500. The tube axis 500 may be a longitudinal axis of the tube part 6 and/or of the syringe casing 2. The tube part 6 is configured for receiving the syringe 100. The tube part 6 has a tube part outer perimeter 8 in a first tube plane perpendicular to the tube axis 500.

The front end 10 has a front end opening 12. The front end 10 has a front end outer perimeter 14 in a second tube plane perpendicular to the tube axis 500. The front end outer perimeter 14 may circumscribe an area larger than an area circumscribed by the tube part outer perimeter 8.

The syringe casing 2 further comprises an optional inner body 16. The inner body 16 is attachable to the syringe 100. The tube part 6 encloses the inner body 16, or at least a part of the inner body 16. The inner body 16 is movable relative to the main body 4. In the example depicted, the inner body 16 is movable relative to the main body 4 along the tube axis 500. In another exemplary syringe casing (not shown) the inner body 16 may be omitted and the tube part 6 may be attachable to the syringe. The auto injector 300 comprises a housing front part 354. The housing front part 354 has a housing front part outer perimeter 356 in a third tube plane perpendicular to the tube axis 500. The cartridge 200 and/or the auto injector 300 may be configured such that the front end outer perimeter 14 circumscribes an area larger than, or equal to, an area circumscribed by the housing front part outer parameter 356. The front end 10 may cover, and/or completely cover, the housing front part 354 when the cartridge 200 is received in the receiving part 304 of the auto injector 300. This may decrease the risk of contaminating the auto injector 300, which is especially important if the auto injector 300 is to be used by multiple users, e.g. patients.

The front end outer perimeter 14 may circumscribe an area larger than an area circumscribed by the tube part outer parameter 8. Thereby, the cartridge 200 may be suitable for front loading into the auto injector 300 as the front end 10 provides a stop for inserting the cartridge into the receiving part 304 of the auto injector 300.

The auto injector 300 comprises an optional display unit 350 for visually displaying information to a user of the auto injector, e.g. to a health care provider. The auto injector 300 comprises an optional user interface 358 for receiving a user input from a user of the auto injector, e.g. a health care provider. The user interface 358 may, as also illustrated, comprise one or more push buttons.

Fig. 5 schematically illustrates an exemplary syringe 100. The syringe 100 may be attached to a syringe casing 2 as described in relation to other figures. The syringe 100 comprises a compartment 102 configured for containing a medicament 126. In the depicted example, the syringe 100 is a dual chamber syringe and the medicament 126 is comprised by a first medicament component 128, e.g. a powder or cake composition, and a second medicament component 130, e.g. a fluid or a liquid component. In other embodiments, the medicament 126 may be a single component and/or the syringe 100 may be a single chamber syringe.

The syringe 100 has a first syringe end 104 and a second syringe end 106. The syringe 100 extends along a syringe axis 530 between the first syringe end 104 and the second syringe end 106. The syringe has a syringe opening 108 at the first syringe end 104. The syringe opening 108 provides fluid communication with the compartment 102. The syringe 100 is configured to expel the medicament 126 through the syringe opening 108. The syringe 100 comprises an optional first syringe channel 1 10, and the syringe 100 is configured to expel the medicament 126 through the first syringe channel 1 10. The syringe opening 108 is a syringe opening of the first syringe channel 1 10. The syringe 100 comprises a first stopper 1 12 movable inside the compartment 102. The first stopper 1 12 is movable at least in a first stopper direction 502 from the second syringe end 106 towards the first syringe end 104.

The syringe 100, as depicted, furthermore comprises an optional second stopper 1 14 between the first syringe end 104 and the first stopper 1 12. The second stopper 1 14 is movable inside the compartment 102. The second stopper 1 14 is movable at least in a second stopper direction 504. As depicted, the second stopper direction 504 may be the same direction as the first stopper direction 502. The second stopper divides the compartment 102 into a first compartment part 134 and a second compartment part 136. The first compartment part 134 contains the first medicament component 128. The second compartment part 136 contains the second medicament component 130. The compartment 102 furthermore comprises a middle bypass section 138. The middle bypass section 138 provides the possibility for fluid communication between the first compartment part 134 and the second compartment part 136, thereby providing that the first medicament component 128 may be combined with the second medicament component 130. When the second stopper 1 14 is positioned in the middle bypass section 138 the first compartment part 134 is in fluid communication with the second compartment part 136. In embodiments wherein the second stopper 1 14 is omitted, the middle bypass section 138 may also be omitted.

The syringe 100, as depicted, furthermore comprises an optional third stopper 1 15 between the first syringe end 104 and the second stopper 1 14. The third stopper 1 15 is movable inside the compartment 102. The third stopper 1 15 is movable at least in a third stopper direction 505. As depicted, the third stopper direction 505 may be the same direction as the first stopper direction 502 and/or the second stopper direction 504. The third stopper 115 provides a seal between a compartment part containing the medicament 126, such as the first compartment part 134 and/or the second compartment part 136, from the syringe opening 108. The compartment 102 furthermore comprises a front bypass section 139. The front bypass section 139 provides the possibility for fluid communication between the compartment part containing the medicament 126, such as the first compartment part 134 and/or the second compartment part 136, and the syringe opening 108. When the third stopper 1 15 is positioned in the front bypass section 139 the compartment part containing the medicament 126, such as the first compartment part 134 and/or the second compartment part 136, is in fluid communication with syringe opening 108 to allow the medicament 126 to be expelled through the syringe opening 108. In embodiments wherein the third stopper 1 15 is omitted, the front bypass section 139 may also be omitted.

The first stopper 1 12, the second stopper 1 14, and/or the third stopper 1 15 may be movable along a stopper axis 512. The first stopper direction 502, the second stopper direction 504, and/or the third stopper direction 505 may be along the stopper axis 512. The stopper axis 512 may, as illustrated, be parallel and/or coinciding with the syringe axis 530.

Fig. 6 schematically illustrates an exemplary operational module 306 for an auto injector, such as the auto injector 300 as described in relation to other figures. The operational module 306 is configured for interacting with a cartridge, such as the cartridge 200 as described in relation to other figures. The operational module 306 comprises a carrier 308 for attaching to a syringe, such as the syringe 100 as described in relation to other figures.

The operational module 306 comprises a stopper operational part 310. The stopper operational part 310 is configured for moving a stopper of the syringe, such as a first stopper of the syringe. In the depicted example, the stopper operational part 310 is configured for moving the stopper of the syringe by movement of a plunger rod 314 which interacts with the stopper of the syringe. The operational module 306 comprises an optional drive axle 316 which is connected to the stopper operational part 310. The drive axle 316 provides that a driver, such as a DC motor, may control the stopper operational part 310 by operating the drive axle 316. Furthermore, the drive axle 316 provides control of the stopper operational part 310 independently of a location of the carrier 308.

The operational module 306 comprises a syringe operational part 312. The syringe operational part 312 is configured for moving the syringe. The syringe operational part 312 is configured for moving the syringe by moving the carrier 308 in a first syringe direction 522 and/or in a second syringe direction 524. The carrier 308 may be moved in order to mix a plurality of medicament components, such as a first medicament component and a second medicament component. Thus, the first syringe direction 522 may be a first mixing direction, and/or the second syringe direction 524 may be a second mixing direction. The syringe operational part 312 may further be configured for moving the syringe and/or the carrier 308 in the first syringe direction 522 to advance a needle of the syringe and/or a needle attached to the syringe, e.g. the syringe may be moved in the first syringe direction 522 for penetration of the skin and insertion of the needle into body tissue.

The syringe operational part 312 and the stopper operational part 310 may provide movements which are parallel, e.g. the stopper operational part 310 may provide movement of the plunger rod 314 in a direction parallel to the first syringe direction 522 and/or the second syringe direction 524. The first syringe direction 522 and/or the second syringe direction 524 may be along an axis, such as the tube axis of the syringe casing.

Fig. 7 shows a flow diagram of an exemplary method 1000 for operating an auto injector, such as for operating an auto injector to perform an air shot. For example, a processing unit of an auto injector, such as a processing unit as described in relation to other figures, may be configured to perform the method 1000.

The method 1000 comprises receiving 1002 an orientation sensor signal and receiving 1004 an optical sensor signal. The orientation sensor signal received 1002 is indicative of an orientation of a syringe containing a medicament. The optical sensor signal received 1004 is indicative of presence of medicament in a first syringe channel of the syringe containing the medicament.

Receiving 1002 the orientation sensor signal and receiving 1004 the optical sensor signal may be interchangeable, such that the optical sensor signal is received 1004 before receiving 1002 the orientation sensor signal. Alternatively, receiving 1002 the orientation sensor signal and receiving 1004 the optical sensor signal may occur simultaneously.

The method 1000 further comprises providing 1008 a control signal based on the optical sensor signal and the orientation sensor signal. The control signal may be provided 1008 to an operational module, e.g. to move a first stopper of the syringe containing the medicament and/or to stop movement of the first stopper of the syringe containing the medicament.

For example, the control signal may be provided 1008 to move the first stopper in the first stopper direction if the received 1004 optical sensor signal indicates that medicament is not present in the first syringe channel and the received 1002 orientation sensor signal indicates that the syringe has a predetermined orientation, e.g. vertical, such as vertical +/- 45 degrees. Alternatively or additionally, the control signal may be provided 1008 to stop movement of the first stopper if the received 1004 optical sensor signal indicates that substance, e.g. medicament, is present in the first syringe channel. Alternatively or additionally, the control signal may be provided 1008 to stop movement of the first stopper if the received 1002 optical sensor signal indicates that the syringe does not have the predetermined orientation.

Fig. 8 shows a flow diagram of an exemplary method 1000' for operating an auto injector, such as for operating an auto injector to perform an air shot. For example, an auto injector, as described in relation to other figures, may be configured to perform the method 1000.

The method 1000' comprises receiving 1002 an orientation sensor signal and receiving 1004 an optical sensor signal. The orientation sensor signal received 1002 is indicative of an orientation of a syringe containing a medicament. The optical sensor signal received 1004 is indicative of presence of medicament in a first syringe channel of the syringe containing the medicament.

The method 1000' further comprises configuring 1006 a control signal based on the received 1002 orientation sensor signal and the received 1004 optical sensor signal. If the received 1004 optical sensor signal indicates that medicament is not present in the first syringe channel and the received 1002 orientation sensor signal indicates that the syringe has a predetermined orientation, e.g. vertical, such as vertical +/- 45 degrees, the control signal is configured 1006 to a first configuration 1014 of the control signal. The first configuration 1014 of the control signal is provided 1008 to move 1010 a first stopper of the syringe, e.g. in a first direction.

If the received 1004 optical sensor signal indicates that medicament is present in the first syringe channel or the received 1002 orientation sensor signal indicates that the syringe does not have the predetermined orientation, the control signal is configured 1006 to a second configuration 1016 of the control signal. The second configuration 1016 of the control signal is provided 1008 to stop movement 1012 of the first stopper of the syringe.

A processing unit of an auto injector, such as a processing unit as described in relation to other figures, may be configured to receive 1002 the orientation sensor signal, receive 1004 the optical sensor signal, configure 1006 the control signal, and provide 1008 the control signal. The control signal 1008 may be provided to an operational module of the auto injector, wherein the operational module is configured for moving the first stopper of the syringe at least in the first stopper direction. Fig. 9 schematically illustrates an exemplary system 400 comprising an auto injector 300 and a cartridge 200. The cartridge 200 comprises a syringe 100 containing a medicament. The auto injector 300 is shown with outer parts, such as the housing, removed, to allow visibility of internal components of the auto injector 300. In the example illustrated, the cartridge 200 is received in the receiving part of the auto injector 300. The auto injector 300 comprises an operational module 306.

The operational module 306 comprises a stopper operational part 310 configured for moving a stopper of the syringe 100, such as a first stopper of the syringe 100. For example, the first stopper of the syringe may be advanced to expel the medicament of the syringe, e.g. to inject the medicament into tissue of a patient, and/or the first stopper may be advanced to combine two or more medicament components, such as a first medicament component and a second medicament component.

The operational module 306 comprises a syringe operational part 312 configured for moving the syringe 100. For example, the syringe operational part 312 may be configured for advancing the needle 1 16, e.g. to insert the needle into tissue of a patient, and/or the syringe operational part 312 may be configured for moving the syringe 100 back and forth in order to mix two or more medicament components, such as a first medicament component and a second medicament component, e.g. to dissolve a powder component in a liquid component.

The operational module 306 comprises a carrier 308. In the example depicted, the syringe 100 is attached to the carrier 308, and the syringe operational part 312 is configured for moving the syringe 100 by movement of the carrier 308. The syringe 100 may be locked to the carrier 308 by a syringe lock (not shown), when the syringe 100 is received in the receiving part of the auto injector 300. The syringe lock may have a locked state and an unlocked state, and the syringe lock may be configured to lock the syringe 100 to the carrier 308 in the locked state.

The operational module 306 comprises one or more drivers, such as a stopper driver 380 and a syringe driver 382. The stopper driver 380 is configured to drive the stopper operational part 310, e.g. via a drive axle 316. The drive axle 316 provides that the stopper driver 380 may drive the stopper operational part 310 in all positions of the carrier 308. In an alternative embodiment, the stopper driver 380 may have been positioned on the carrier 308, reducing the need for a drive axle 316. The syringe driver 380 is configured to drive the syringe operational part 312, such as to move the carrier 308 and/or the syringe 100. The stopper driver 380 and/or the syringe driver 382 may be DC motors, e.g. DC motors with or without brushes, e.g. the stopper driver 380 may be a brushed DC motor and/or the syringe driver 382 may be a brushless DC motor. A brushless DC motor may be preferred due to higher durability of a brushless DC motor. Especially for the syringe driver 382 a brushless DC motor may be preferred due to many and/or rapid movements performed by the syringe driver 382.

The auto injector 300 comprises sensors, such as an optical sensor 336. In the depicted example, the auto injector 300 comprises a plurality of optical sensors 336. The optical sensor(s) 336 may be configured for detecting medicament and/or blood in a channel, such as the needle chamber. The optical sensor(s) 336 may be configured for reading an optical code of the cartridge 200, such as an information code of the cartridge 200. A plurality of optical sensors 336, as shown, may provide the possibility of optical reading and/or detection for different positions of the syringe 100.

The auto injector 300 comprises a power unit 376, such as a battery, such as a rechargeable battery, such as a lithium-ion battery. The power unit 376 may supply power to electronic components of the auto injector, e.g. the stopper driver 380, the syringe driver 382, a processing unit, a memory, sensors, such as the optical sensor(s) 336, a user interface, etc.

The auto injector 300 comprises a contact switch 378. The contact switch 378 may provide a signal indicative of the cartridge 200 being inserted in the auto injector 300, e.g. of the cartridge 200 being received in the receiving part of the auto injector 300. Additionally or alternatively, the contact switch 378 may provide a signal indicative of the cartridge 200 and/or the syringe 100 being pressed against a user's skin, e.g. a patient's skin. Thus, the contact switch 378 may be a skin sensor.

The cartridge 200 comprises a cover element 24. The cover element 24 is movable between a first position, as illustrated, and a second position. In the second position, the cover element covers at least a portion of the front end opening, and thereby reduces the front end opening, in order to provide protection of the needle 1 16, when the syringe 100 is retracted, such that the needle 1 16 is enclosed inside the cartridge 200.

The cartridge 200 comprises a removable sheet 20. The removable sheet 20 covers the front surface and is configured for removal before abutment of the front end to a user's skin, e.g. a patient's skin. The removable sheet 20 may provide that a front surface of the front end is maintained sterile until removal of the removable sheet 20, thereby reducing the risk of infection.

Although particular features have been shown and described, it will be understood that they are not intended to limit the claimed invention, and it will be made obvious to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the claimed invention. The specification and drawings are, accordingly to be regarded in an illustrative rather than restrictive sense. The claimed invention is intended to cover all alternatives, modifications and equivalents.

LIST OF REFERENCES

2 syringe casing

4 main body

6 tube part

8 tube part outer perimeter

10 front end

16 inner body

20 removable sheet

24 cover element

100 syringe

102 compartment

104 first syringe end

106 second syringe end

108 syringe opening

1 10 first syringe channel

1 12 first stopper

1 14 second stopper

1 15 third stopper

1 16 needle

124 needle tip

126 medicament

128 first medicament component

130 second medicament component

134 first compartment part

136 second compartment part

138 middle bypass section

139 front bypass section 200 cartridge

300 auto injector

302 housing

304 receiving part

306 operational module

308 carrier

310 stopper operational part

312 syringe operational part

314 plunger rod

316 drive axle

330 processing unit

332 orientation sensor

334 orientation sensor signal

336 optical sensor

338 optical sensor signal

340 control signal

350 display unit

354 housing front part

356 housing front part outer perimeter

358 user interface

360 light transmitter

362 light receiver

376 power unit

378 contact switch

380 stopper driver

382 syringe driver

400 system 500 tube axis

502 first stopper direction

504 second stopper direction

505 third stopper direction

512 stopper axis

522 first mixing direction/first syringe direction

524 second mixing direction/second syringe direction

530 syringe axis

1000, 1000' method for operating an auto injector 1002 receiving orientation sensor signal

1004 receiving optical sensor signal

1006 configuring control signal

1008 providing control signal

1010 move the first stopper

1012 stop movement of the first stopper

1014 first configuration of control signal

1016 second configuration of control signal