EP4373548A1

EP4373548A1 - Autoinjector with a separable electronics module

Info

Publication number: EP4373548A1
Application number: EP22754077.0A
Authority: EP
Inventors: Leos URBANEK; Gabriel KALBERMATTER; Markus Tschirren; Dominik ZUMSTEIN; Christian Schrul; Simon Martin BOSSHARD
Original assignee: Ypsomed AG
Current assignee: Ypsomed AG
Priority date: 2021-07-22
Filing date: 2022-07-21
Publication date: 2024-05-29
Also published as: EP4122512A1; US20240148975A1; WO2023001988A1; CN118043090A

Abstract

The invention relates to an injection device for subcutaneously administering a maximum content of a product container through a cannula at a distal end of the product container, comprising a device housing (2) having an opening at a proximal end, a module housing (17) for covering the opening, which module housing is separable from the device housing by a separating operation, a drive (9, 13), which is arranged in the device housing, for moving an advancing element (7) and for the one-time automatic ejection of the contents of the product container. An electronics module (16) is held in the module housing, with a sensor (16a) for detecting the discharging, and a mechanical securing mechanism (19) is provided for enabling the separating operation as or after the automatic ejection is triggered.

Description

AUTOINJECTOR WITH SEPARABLE ELECTRONIC MODULE

TECHNICAL AREA

The present invention relates to the field of medical injection devices for administering liquid substances, in particular medicaments or medicinal substances such as insulin and hormone preparations. The invention relates to an auto-injector with an energy store for dispensing a predetermined dose from a product container that is used once.

BACKGROUND OF THE INVENTION

Injection devices or injection devices for the simplified administration of a substance include so-called auto-injectors, which have an energy store with which the dispensing can be carried out automatically, ie without external force to be supplied or applied by a user. The energy store advantageously stores the energy required for automatic substance delivery in mechanical form. Such an energy store can be a spring which is built into the injection device in a tensioned state and releases energy when it relaxes. The energy is delivered to a piston rod or a pressure element, which pushes a piston into a product container. The energy store can also be provided in order to automate the process of inserting an injection needle. Alternatively, the piercing process can be carried out manually, ie exclusively by a user, without using energy stored in the injection device for this purpose.

The injection device can comprise a product container holder for accommodating a product container, it being possible for the product container to be held radially, axially and preferably also in a rotationally fixed manner in the product container holder. The product container holder can be connected to the housing of the injection device in an axially fixed and non-rotatable manner, or it can be movable relative to the housing during a piercing and/or needle retraction process. The product container can be a carpule for repeatedly detachable connection with disposable injection needles or a disposable pre-filled syringe with an injection needle connected thereto inseparably. The product container has a hollow cylindrical Product container section that slidably supports a piston or stopper. The piston can form a sealing gap with the inner circumference of the product container section and can be displaced in a distal direction by means of a piston rod in order to dispense product from the product container via the injection needle. The injection device can have a needle protective sleeve which, after the injection has been completed, projects distally over the distal end of the injection needle or is displaced into this position relative to the housing while a needle protective sleeve spring is relaxed, in order to prevent accidental access to the injection needle and thereby reduce the risk of injury . In the case of an auto-injector, the needle protection sleeve can also serve as a triggering element for triggering the dispensing of the product, the needle protection sleeve being displaced in the proximal direction relative to the housing for this purpose. Alternatively, the triggering of the auto-injector can be achieved by pressing a trigger button on the auto-injector, with the needle guard serving at least as a visual shield before the auto-injector is used. The patent application PCTEP2021057168 describes an autoinjector comprising a

Housing with a longitudinal axis, a product container, a torsion spring prestressed for the one-off dispensing of a maximum content of the product container, a drive element, and a propulsion element. To dispense a maximum or at least a predetermined amount of liquid from the product container, the torsion spring causes the drive element to rotate about the longitudinal axis, and the rotating drive element causes a propulsion movement of the propulsion element to displace a piston in the product container. The auto-injector also includes a permanently installed rotation sensor for detecting the start of dispensing. The auto-injector includes a communication unit for communication with a mobile or stationary third-party device and/or a display unit for displaying a state of the auto-injector. The communication unit and/or the display unit and an energy source for feeding them are arranged on a printed circuit board, which can be removed from the rest of the autoinjector together with a housing part that can be easily separated, preferably by predetermined breaking lines in the housing. All electronic components of the rotation sensor that are critical for disposal are also preferably arranged on the printed circuit board, so that no electronic components remain in the autoinjector after the printed circuit board has been removed. The patent application WO 2017/129314 describes an auto-injector with a detector for detecting the start of a discharge based on a movement of a trigger member which is pushed proximally by a needle guard when the auto-injector is placed on the puncture site. The successful detection activates a communication unit of the autoinjector. A proximal movement of an end click element at the end of the payout is detected by a second detector. The communication unit is permanently connected to the auto-injector or is part of an additional module that can be connected to the auto-injector by the user himself.

The term "product", "medicament" or "medicinal substance" in the present context includes any flowable medicinal formulation which is suitable for controlled administration by means of a cannula or hollow needle into subcutaneous or intramuscular tissue, for example a liquid, a solution, a gel or a fine suspension containing one or more active medicinal ingredients. Thus, a medicament may be a single active ingredient composition or a premixed or co-formulated multiple active ingredient composition from a single container. The term includes in particular medicinal products such as peptides (e.g. insulins, insulin-containing medicines, GLP-1-containing and derived or analogous preparations), proteins and hormones, biologically derived or active substances, substances based on hormones or genes, nutritional formulations, enzymes and other substances both in solid (suspended) or liquid form. The term also includes polysaccharides, vaccines, DNA or RNA or oligonucleotides, antibodies or parts of antibodies as well as suitable basic, auxiliary and carrier substances.

The term “distal” refers to a side or direction directed toward the front, puncture-side end of the administration device or toward the tip of the injection needle. In contrast, the term “proximal” designates a side or direction directed towards the rear end of the administering device opposite the end on the puncture side.

In the present description, the terms “injection system” or “injector” mean a device in which the injection needle is removed from the tissue after a controlled amount of the medicinal substance has been released. In contrast to an infusion system, the injection needle in an injection system or in an injector does not remain in the tissue for a longer period of several hours. PRESENTATION OF THE INVENTION

It is the object of the invention to specify an injection device for automatically dispensing a liquid from a product container, with an electronics module that can be safely separated for separate disposal. The task is solved by an injection device with the features of the independent claims. Preferred embodiments of the invention are subject of the dependent claims.

According to the invention, the injection device for the subcutaneous administration of a maximum or the entire content of a product container, in particular a dose of a liquid medication, through a cannula or injection needle preferably non-detachably attached to a distal end of the product container, comprises the following components:

- A device housing with a grip area for gripping and holding the injection device by a user during administration, defining a longitudinal direction, and with an opening for mounting purposes at a proximal end.

- A module case or a module cap for covering or closing the opening of the device case, which is separable from the device case by a user's separating operation.

- A drive arranged in the device housing with an energy store in the form of a prestressed dispensing spring for moving a propulsion member in the longitudinal direction and for the one-time automatic and preferably non-electrical dispensing of the contents of the product container.

- An electronic module held in the module housing with a sensor for detecting a process of distribution, and with a communication unit for wireless transmission of a report on the detected process of distribution. The electronic module comprises at least all electronic components of the injection device that are relevant for disposal. With the exception of the product container and metallic components such as mechanical springs or electrical conductors in the form of wires or flexible conductors, only plastic parts of the injection device remain after the separation process, which can be disposed of as medical waste in a known way.

According to the invention, the injection device comprises a mechanical safety mechanism for preventing or blocking the separation process before the start of distribution and for enabling or unlocking the separation process at the earliest with or after triggering the automatic distribution. This will prevent that Electronic module is removed from the injection device before the start of the injection and the detector cannot detect the start of the injection. The release of the separation process takes place at the latest with the last step of the injection process, and preferably before the removal of the injection device from a puncture site. This additionally ensures that the separation process can be carried out and the electronics module can be separated from the injection device, even if incorrect manipulation or problems with the needle protection device should occur when removing the injection device from the puncture site.

In an advantageous variant, the separating process includes a rotating release movement of the module housing relative to the device housing, which can be followed by an axial release movement similar to a bayonet lock, or which can be preceded by an axial release movement of the module housing towards the device housing, similar to a child-proof safety rotary lock. Alternatively, the separating process includes a purely axial release movement of the module housing away from the device housing, for example to release a snap connection between the module and device housing.

In contrast to a purely rotating or transverse release movement, in particular an axial release movement of the module housing towards the device housing is associated with an expenditure of force, which causes a painful movement of the needle in the injection site for the user when the injection device is attached. The expectation of this pain additionally motivates the user to wait with the axial release movement until after the injection device has been removed from the injection site. A necessary use of a tool to carry out the process of separating the module housing released for separation from the device housing can further motivate the user to wait until after the injection before separating the electronics module from the injection device.

In a preferred embodiment, the mechanical securing mechanism comprises a release element in the form of a clip, a tab, or a bolt; either as an independent component, or as part of a housing insert attached to the housing, or in one piece with the module or device housing. In a blocking position of the release element, the release element locks or blocks the release movement before the start of the distribution, and releases the release movement with or after the release is triggered. For this purpose, the release element assumes a release position prior to the removal of the injection device from the injection site, causing immediate release by a triggering movement by the user, for example a displacement of the needle guard when the device is pressed onto the injection site, or by a release spring of the drive after release, or by a signaling spring for acoustic or tactile signaling of the beginning or end of the release. The release position is thus assumed before the injection device is removed from the injection site and is not brought about by a needle protection spring expanding distally on this occasion. The release stroke of the release element into the release position preferably takes place against a bias of the release element into the blocking position, with which a spontaneous release of the separating process is prevented, the latter also being able to occur as a result of axial frictional forces on the release element. Instead of having an immediate effect, the movement of the release element into the release position can also first force an additional blocking element into a release position enabling the release movement.

In a preferred embodiment, the injection device comprises a dispensing spring in the form of a compression spring for driving a propulsion element in the form of a piston sleeve, and a holding element for holding the dispensing spring in a prestressed state before it is triggered, at the proximal end of which the compression spring is supported. The release element is moved into the release position by a proximal movement of the holding element caused by the dispensing spring at the beginning or at the end of the dispensing. Alternatively, the injection device comprises a dispensing spring in the form of a torsion spring and a rotating drive element in the form of a threaded rod for driving a propulsion element in the form of a piston sleeve with an internal thread. The release element is moved into the release position by a proximal movement of the drive element when counter-pressure is built up on the propulsion element by the liquid in the product container.

In a preferred embodiment, the separating process includes an axial release movement in the direction of a longitudinal axis of the injection device, with the module housing being snapped by snap elements on or to the device housing or a housing insert, which are prevented from being released or snapped out by the release element in the blocking position via non-axial blocking surfaces .

In a preferred embodiment, the separating process includes a rotating release movement in a plane perpendicular to a longitudinal axis of the injection device. Included a radially inwardly pointing projection on the module housing is prevented from rotating by the release element in the locking pitch via non-tangential locking surfaces. Alternatively, if the release element itself rotates during the release movement, the latter is prevented from rotating in the blocking position by a radially inward-pointing projection on the device housing or on a housing insert in the device housing.

In a preferred embodiment, the electronic module comprises a communication unit or a transmitter and a battery or other energy store for feeding the communication unit, which is kept in a battery compartment and can only be removed from the electronic module and taken to a specific collection point when the module housing is separated. The battery is preferably clamped only lightly or not at all in the battery compartment and falls out of the battery compartment purely due to gravity during or after separation, whereby it can still be held on a thread that is not tear-resistant and is therefore not lost. The electronics module preferably does not have a display for displaying different alphanumeric characters, but at most an optical status display encoded by a color or light pulse pattern.

In a preferred embodiment, the sensor is designed and/or arranged to detect an axial or radial movement of the holding element, the drive element, or the propulsion element caused by the dispensing spring. In particular, the movements of the holding element and the drive element can take place in the proximal direction counter to the dispensing direction and can be intercepted after a short distance by a support or stop element fixed to the housing. Alternatively, the sensor is designed to detect an axial movement of a needle protection sleeve or a signal element caused by a needle protection spring, in particular the presence or absence of the signal element in its proximal position in contact with a signal stop. A single sensor can determine both the start and the end of the distribution, for example if the signal element is moved at the beginning of the distribution by the force of the distribution spring and under tension of the needle protection spring by a clamping stroke away from the signal stop. Otherwise, two or more sensors can also be provided. An axial extension in the form of a plunger or pin on the said movable elements and/or on the sensor, or implemented by a separate switching adapter, can ensure mechanical contact or mutual frictional connection to the sensor. The electronic module comprises a processor unit, which is switched on by a mechanical switching detector as a sensor from a dead state or is woken up by an electronic detector as a sensor from an energy-saving mode. The detected distribution, together with a time stamp and other information such as the duration of the distribution or a holding time, are wirelessly transmitted to a mobile device by the communication unit. This transmission can also take place or be terminated after the electronic module has been separated. The processor unit can additionally be configured to generate an acoustic or tactile indication to the user, which indicates the end of a hold time of a few seconds after the end of the distribution. An example of visual feedback on the expiry of the hold time includes the change of an LED from a flashing to a dormant state or vice versa, this indication stops at the latest when the injection device is lifted from the injection site.

The injection device is preferably an auto-injector with a dispensing spring that is maximally prestressed upon delivery or before the auto-injector is put into operation for a one-off dispensing of the entire or at least a predetermined content of the product container. Accordingly, the auto-injector does not have a dose selection mechanism. A pre-filled disposable syringe comprises the product container and an injection needle permanently attached to it and is held axially fixed in the housing of the autoinj ector. The autoinj ector, or at least the ready-to-use syringe and the syringe holder, are therefore only intended for single use.

In addition to the processor unit for evaluating the data from the sensor, the electronics module can include a Bluetooth transmitter device for the wireless transmission of information about the distribution. The transmission device is designed for repeated transmission of the preferably suitably encrypted information together with a non-encrypted, unique identifier of the autoinjector. The transmitting device operates preferably and exclusively as a beacon in a Bluetooth broadcast mode and communicates the information and the identifier in the form of advertising packets.

A further aspect of the invention relates to the modular design of a device family or platform with two auto-injectors, which have as many identical or interchangeable components as possible and of which only a first auto-injector has an electronic module. A family of devices according to the invention thus includes a first and a second autoinjector, both with the same elongated device housing Gripping and holding of the auto-injector by a user, the same syringe holder for holding a pre-filled syringe, the same propulsion element for dispensing a dose by propelling a plunger in the syringe, the same triggering mechanism for triggering dispensing, and the same needle guard for covering the side of the needle after dispensing. At the proximal end, the first autoinjector has a module housing for covering an opening in the device housing, which accommodates an electronics module and can be detached from the device housing. At the proximal end, the second autoinjector has an end or end cap to cover the opening of the device housing, which is permanently and non-detachably or not non-destructively connected to the device housing, preferably snapped, welded or glued. Another difference is that the first auto-injector has a release element in addition to the electronic module with sensor and communication unit. The release element locks or blocks a release movement of the module housing before the distribution begins in a locking position. The first autoinjector preferably also has a housing insert which is positively connected to the proximal end of the device housing in a rotationally and axially fixed manner and serves as a module adapter for the electronics module, the release element and/or the module housing.

The device family preferably includes a third auto-injector, which is identical to the first auto-injector except for the fact that the module housing of the third auto-injector is not intended to be separated from the device housing or the housing insert by the user. The module housing and/or the housing insert of the third autoinjector therefore have differently shaped snap or connecting elements than the module housing and/or the housing insert of the first autoinjector. In particular, the third auto-injector also has a release element, even if this is not used or has become obsolete due to the aforesaid non-detachable connecting elements. In this case, the electronic module is disposed of together with the third auto-injector.

The needle protective sleeve springs for moving the needle protective sleeve into a needle protective position and the dispensing springs of the two autoinjectors are preferably also identical. However, the lack of drive of a release element in the second autoinjector can also accept a spring dimensioned with a smaller margin. CHARACTERS

In connection with the appended figures, preferred embodiments of the invention are described below. These are intended to show basic possibilities of the invention and should in no way be interpreted in a restrictive manner. Show it

1 shows an exploded view of an autoinjector with a compression spring drive;

2 shows a first embodiment of the securing mechanism;

3 shows a first variant of a second embodiment of the safety mechanism; 4 shows a second variant of the second embodiment;

5 shows a third variant of the second embodiment;

6 shows a partial longitudinal section of an autoinjector with a torsion spring drive;

7 shows a third embodiment of the safety mechanism, and FIG. 8 shows a fourth variant of the second embodiment.

FIGURE DESCRIPTION

1 shows an exploded view of an autoinjector comprising a drive with a compression spring designed as a helical spring. The auto-injector has a sleeve-shaped, elongate injector or device housing 2 with a longitudinal axis L, which the user holds in one hand during the injection. A pre-filled syringe, not shown, is accommodated in a syringe holder 1, which in turn is locked in the housing 2 in a rotationally and axially fixed manner. When delivered, a pull-off cap 4 is arranged at the distal end of the housing 2 and is removed before the auto-injector is used. A needle protective sleeve 3 can be displaced relative to the housing 2 and along the longitudinal axis L by an actuating stroke HB in the proximal direction into an actuated position in order to trigger a product distribution. A mechanism holder 5 is snapped to the housing 2 in a rotationally and axially fixed manner and presses the pre-filled syringe distally into the syringe holder 1 by means of a retaining spring section 5c.

The auto-injector has a dispensing spring 9 in the form of a helical spring acting as a compression spring, which in the delivery state is almost completely surrounded by a sleeve-shaped propulsion member 7 and exerts a force on it in the distal direction. The dispensing spring 9 is supported with its proximal end on a holding element 6 which has two arms 6b, with an engagement element 6a being arranged on each arm 6c. The engagement elements 6a point radially towards the longitudinal axis L and engage in the delivery condition in recesses on the outer surface of the propulsion element 7 . A switching module with a switching sleeve 15 and a locking sleeve 8 prevents deflection of the two arms 6b, which also prevents movement of the propulsion member 7 relative to the holding element 6 in the distal direction. The switching sleeve 15 is at least non-positively connected to the proximal end of the needle guard 3 and is pushed by a needle guard spring 10 distally. In order to trigger the distribution, the needle protection sleeve 3 and the switching module 15, 8 are moved proximally, as a result of which the needle protection spring 10 is tensioned and the arms 6b can deflect. As a result, the axially fixed coupling between the propulsion member 7 and the holding element 6 is eliminated, and while the former is being moved distally, the holding element 6 can be displaced proximally by a small initial stroke up to an axially fixed stop. When the autoinjector is removed from the injection site, the needle guard 3 is moved distally by the needle guard spring 10 and locked by the switching module 15, 8 in a needle guard position. The needle protection spring 10 is a metal spring that acts as a compression spring and is designed as a helical spring and is supported with its proximal end on a signal element 11 . In the delivery state, the signal element 11 is in contact with a signal stop of a housing insert 12 and has two arms 11b, with an engagement element 11a being arranged on each arm 11b. The engagement elements 11a point radially toward the longitudinal axis L and, in the delivery state, engage in further recesses of the propulsion element 7 . At the beginning of the distribution, the signal element 11 is thereby moved by a clamping stroke away from the signal stop 12a, then held in engagement with the locking sleeve 8 by the outer surface of the propulsion element, and at the end of the distribution for a movement accelerated by the needle protection spring 10 released proximally towards the signal stop 12a. Details on the design of the auto-injector with a compression spring drive are described in patent application WO 2021160540 A1.

The housing insert 12 is positively connected to the proximal end of the housing 2 in a rotationally and axially fixed manner and can also complement or lengthen it axially and generally serve as a module adapter for an electronics module housing or device end cap. A detachable module housing 17 for an electronic module 16 is provided at the proximal end of the housing insert 12 . The electronics module 16 includes a sensor 16a and a battery 16b, further a processor unit, a communication unit, and / or a Light source for optical signaling of an operating status. The sensor 16a is designed to detect or monitor the presence of the signal element 11 in its proximal position in contact with the signal stop 12a, or the absence of the signal element from this position during the duration of the distribution. The sensor 16a of the electronics module 16 is designed as a switching detector, the sensor 16a and/or the signal element 11 have an axial extension in the form of a ram to ensure a mutual non-positive connection. Alternatively, a switching adapter can be provided as a separate component for transmitting the position of the signal element 11 to the switching detector via an axial, tilting, or other deflection movement. A processor of the electronic module 16 evaluates the detected movements of the signal element and reports in particular the time when an injection has taken place via a communication module.

2 shows an axial view of the autoinjector from the rear with the module housing 17 cut off and without the electronic module (above) and a detail of a longitudinal section through a plane AA (below). In this embodiment of the invention, the module housing 17 is attached to the housing insert 12 by means of a snap connection. Two flexible snap elements 12b on the housing insert engage behind radially inwardly protruding protrusions of the module housing 17 and are prevented from inward deflection by a release element 19 in the form of a bending arm on the module housing. Due to the small initial stroke of the holding element 6 in the proximal direction, the release element 19 is deflected or bent and the snap-in elements 12b are released, so that the user can now remove the module housing 17 axially backwards from the housing insert.

The functions and properties of the housing insert can also be taken over directly by the housing of the injection device; a separate but firmly connected housing insert is primarily advantageous for manufacturing reasons. Accordingly, the snap-in elements can also be provided on the housing of the injection device, or they can also be attached to the module housing and snap into openings in the housing. With this concept, the module housing can also be separated using a screwdriver or similar tool. To do this, the screwdriver is guided in the direction of the arrow through an opening in the module housing under an elastic end of the release element and tilted. The release element can also be a separate component and can be moved backwards as a whole by the holding element. This will do that Release element not bent and can also release diagonally opposite snap elements.

3 shows a longitudinal section of a first variant of a second embodiment of the invention, in which the module housing can be released by means of a rotary movement. A release element 19 is anchored in the module housing 17 in a rotationally fixed manner via two diagonally opposite anchors 19a and is prestressed distally via two spring arms 19b, so that in the locked state (top) a rounded rectangular locking profile 19c of the release element 19 engages in a matching profile receptacle 12c of the housing insert 12. A pin-shaped distal extension 19d of the release element hits the proximal end of the holding element 6 and is pushed proximally by its initial stroke against the pretension of the spring arms 19b, whereby the locking profile 19c is moved out of the recess 12c and the release element 19 is rotated with the module housing 17 can (below).

Instead of the rectangular blocking profile, any profile that is non-rotationally symmetrical about the longitudinal axis L can be used to absorb a torque, for example a cross or star shape, or a profile with multiple characteristics for engaging multiple impressions. The locking profile may include a distally protruding structure on the release member for engaging a recess on the housing insert, or a proximally protruding bulge on the housing insert for engaging a corresponding indentation on the release member. Instead of the spring arms, separate spring elements can be provided for the distal prestressing of the release element and thus prevent a spontaneous release of the release movement, or the release element is non-positively connected to the holding element via the pin-shaped distal continuation. Similar to a bayonet lock, the rotating loosening movement of the module housing relative to the device housing can be followed by an axial loosening movement, or the rotating movement is part of a screwing loosening movement.

4 shows a longitudinal section of a second variant of the second embodiment of the invention in the delivery state (above) and in the released state (below). The sectional plane is rotated by 90° compared to that in FIG. In the delivery state, the release element 19 is held on the housing insert 12 by means of catches 19e Keep release position of the release element. After the triggering, the dispensing spring 9 pushes the release element 19 in a proximal direction via the extensions 19d and thus the catches 19e out of their holding position. Opposite peripheral ends of the release member are moved axially away from cam 17a, releasing it for pivotal movement. As an alternative or in addition to this, as in the previous variant, a rotation blockage is possible by means of a profile mount and locking profile.

5 shows a longitudinal section of a third variant of the second embodiment of the invention in the delivery state (above) and in the triggered state (below), in which the release element 19 is formed in one piece with the housing insert 12 and thus does not rotate itself during the rotating release movement. The release element 19 is therefore not a separate component and therefore cannot fall out and get lost at the moment the module housing 17 is removed. As in the first embodiment, the release element 19 is elastically or articulated and flexible and connected to the housing insert on one side. The opposite end of the spring arm 19b is in a rotation-blocking stop with a radially inwardly projecting cam 17a of the module housing 17. The initial stroke of the holding element 6 raises the end of the spring arm 19b proximally and the cam 17a is released for rotation.

8 shows a cross section (above) and a longitudinal section (below) of a fourth variant of the second embodiment of the invention in the delivery state, with indication of the respective sectional planes BB and CC. The release element 19 is permanently anchored or guided in the module housing 17 in a rotationally fixed manner via two diagonally opposite anchors 19a, both in the delivery state shown and after the release movement of the release element has taken place in the proximal direction. Only in the delivery state, two rigid legs 19f of the release element are frictionally connected to blocking or counter-contact surfaces 12g of the housing insert 12 via a radially extended contact surface 19g and are thus prevented from rotating counterclockwise (viewing distally, Fig. 8). The radial extension of a contact surface 19g is at least one third, preferably at least half the length of the leg 19f, and thereby distributes the force on the housing insert in the event of a rotation attempt before release. When the electronics module 16 is separated, the release element can remain in the module housing 17 by means of a distal limitation of mobility or in the housing insert 12 by means of a proximal limitation of mobility in the electronics module or in the autoinjector a longitudinal section of the proximal end of an autoinjector comprising a drive with a torsion spring designed as a spiral spring and otherwise largely functionally identical components as in the second embodiment. The autoinjector comprises a housing 2, a housing insert 12 firmly connected to the housing, a drive element 13 in the form of a threaded rod, a propulsion element 7 in the form of a sleeve with an internal thread engaging with the thread of the threaded rod, and a dispensing spring 9 in the form of a drive - or spiral spring. The latter is wound on the shank of a spring coil 9a and is connected to it in a rotationally fixed manner at an inner end. The spring coil 9a in turn is coupled to the drive element 13 in a rotationally fixed but not axially fixed manner. A needle guard also serves as a trigger element to trigger the

Product distribution, with a switching module coupled axially to the needle guard releases a holding element and thereby enables the axial propulsion of the propulsion element 7 or the rotation of the drive element 13 or the spring coil 9a. After the discharge has been triggered, the propulsion element 7 is brought into contact with the stopper of the syringe, whereupon a counter-pressure builds up on the stopper in the liquid in the syringe, the longitudinally guided propulsion element 7 is briefly blocked and the rotating threaded rod as the drive element 13 is thereby screwed proximally. As soon as the threaded rod for its part comes up against a distally directed stop 12d with a shoulder, the counter-pressure is overcome and the propulsion element 7 completes the delivery stroke. The proximal movement of the drive element 13 is comparable to the initial stroke of the holding element of the compression spring embodiments and sufficient for an axial release movement of the release element 19.

Alternatively, a proximal end face of a proximal flange of an axially fixed spring coil can have a non-continuously rotationally symmetrical structure with at least one plateau protruding proximally and/or an axial depression. A continuation of the release element that extends distally and is radially offset from the axis, which is in a distal position before the release is triggered in the recess, is lifted onto said plateau or pushed proximally by the rotation of the spring coil and by means of suitable snappers held in this proximal release position. Instead of a plateau in the form of a sector, a radially aligned rib protruding in the proximal direction can also ensure the axial deflection of the release element. Details on the configuration of the auto-injector with a torsion spring drive and a rotation sensor for the alternating, continuous detection of at least two rotational positions per revolution of the drive element during dispensing are disclosed in patent application WO 2021191095 A1. Fig.7 shows an exploded view of four components of the embodiment

6 with a bayonet catch between the module housing 17 and the housing insert 12. The module housing 17 is additionally cut along the longitudinal axis. The separating movement thus includes a rotation of the module housing relative to the housing insert 12 in the direction of rotation indicated by the arrow. For this purpose, the housing insert 12 has a rotary guide 12e for a cam 17a on the inside of the module housing 17 on an outside. The initial position of the cam 17a in the rotary guide 12e is limited by a slot-shaped axial guide 12f through which one end of the release element 19 protrudes. The latter is axially coupled to a proximal end of the drive member 13 and is raised by the proximal movement of the drive member 13 by at least the axial extent of the cam 17a. The module housing shown comprises two cams 17a, each with an angular extent of approximately 45°, with an angular extent of less than 45° being possible for up to four rotary guide/cam pairs.

As an alternative to the described proximal movement of the drive element, a rotational movement of the threaded rod can be converted into an axial movement of the release element via a threaded engagement with the release element. For this purpose, the threaded rod and the release element have a thread overlap corresponding to the release stroke of the release element, so that the release element disengages from the threaded rod at the end of the proximal movement and can be moved axially away from it. Also conceivable is a flexible release element acting on one side, as in FIG.

Further alternatively, the proximal movement of the release element can be caused by a final stroke of the holding element or a signaling element as described above at the end of the distribution. Particularly suitable, however, is a signaling element without an initial or loading movement, ie with only a signaling movement against a stop at the proximal end of the autoinjector, ie, for example, a signaling element against which the dispensing spring contacts supported proximally, and which is released at the end of the distribution from the proximal end of the propulsion member for a signaling movement proximally.

REFERENCE LIST

1 syringe holder 12d stop

2 housing 12e rotary guide

3 Needle protection sleeve 12f axial guide

4 Pull-off cap 12g locking surface

5 mechanism holder 13 drive element

5 c retaining spring section 14 needle protective cap

6 retaining element 15 switching sleeve

6a first engagement element 16 electronic module

6b arm 16a sensor

7 propulsion member 16b battery

8 locking sleeve 17 module housing

9 pouring spring 17a cam

9a spring coil 18 switching adapter

10 needle guard spring 19 release element

11 signal member 19a anchorage

11a first engagement member 19b spring arm

11b arm 19c locking profile

12 Housing Insert 19d continued

12a signal stop 19e snapper

12b snap element 19f leg

12c recess 19g contact surface

Claims

PATENT CLAIMS

Claims 1. Injection device for subcutaneous administration of a maximal content of a product container through a cannula at a distal end of the product container, comprising

- a device housing (2) with an opening at a proximal end,

- a module housing (17) for covering the opening, which can be separated from the device housing (2) by a separating process,

- a drive (9, 13) arranged in the device housing (2) for moving a propulsion member (7) and for the one-time automatic pouring out of the contents of the product container,

- An electronic module (16) held in the module housing (17) with a sensor (16a) for detecting the distribution, characterized by a mechanical safety mechanism (19, 12b; 12c, 19c; 17a) for releasing the separation process with or after triggering the automatic distribution.

2. Injection device according to claim 1, characterized in that the separating process involves a rotary release movement of the module housing (17) relative to the device housing (2) and/or an axial release movement of the module housing (17) towards the device housing (2) and/or comprises an axial release movement of the module housing (17) away from the device housing (2).

3. Injection device according to claim 2, characterized in that the mechanical safety mechanism comprises a release element (19) for blocking the rotary or axial release movement before triggering the distribution in a blocking position of the release element (19) and for releasing the release movement before removing the injection device from an injection site in a release position of the release element (19).

4. Injection device according to claim 3, wherein the injection device has a dispensing spring (9) for driving a propulsion element (7) and a holding element (6) for holding the dispensing spring (9) in a prestressed state prior to triggering or a drive element (13) for transmission a distribution force of the distribution spring (9) on the propulsion element (7), characterized in that the release element (19) is moved to the release position by a proximal movement of the holding element (6) or the drive element (13).

5. Injection device according to claim 3, characterized in that the separating process comprises an axial release movement and the module housing (17) is snapped by snap elements (12b) which are prevented from releasing by the release element (19) in the locking position.

6. Injection device according to claim 3, characterized in that the separating process comprises a rotating release movement and the release element (19) in the locking position prevents a radial projection (17a) on the module housing (17) from rotating or is prevented from rotating by a radial projection.

7. Injection device according to Claim 3, characterized in that the separating process comprises a rotating release movement and the release element (19) is connected to the module housing (17) in a torque-proof manner and is in contact with a blocking surface (12g) on the is prevented from rotating.

8. Injection device according to claim 1, characterized in that the electronic module (16) has a battery (16b) for feeding a communication unit of the electronic module (16), which can only be removed from the electronic module (16) when the module housing (17) is separate.

9. Injection device according to claim 1, comprising a dispensing spring (9) for driving a propulsion element (7) and a holding element (6) for holding the dispensing spring (9) in a prestressed state before it is triggered, or a drive element (13) for transmitting a dispensing force of the dispensing spring (9) on the propulsion element (7), characterized in that the sensor (16a) detects an axial or radial movement of the propulsion element (7), the holding element (6), or the drive element (13 ) detected.

10. Injection device according to claim 1, comprising a needle protective spring (10) for driving a needle protective sleeve (3) distally and/or a signal element (11) proximally, characterized in that the sensor (16a) has a needle protective spring (10) caused axial movement of the needle guard (3) or the signal member (11) detected.

11. Injection device according to claim 1, characterized in that the injection device is an auto-injector with a maximally prestressed dispensing spring (9) for a one-off dispensing of the entire or at least a predetermined content of a pre-filled syringe. 12. A first auto-injector according to claim ll and a second auto-injector, the second

Autoinjector having a second device housing identical to the first autoinjector with an opening at a proximal end, an identical drive, and an end cap non-detachably connected to the second device housing for covering the opening. 13. The first auto-injector according to claim 12, characterized by a housing insert

(12), which is rotationally and axially fixed to the proximal end of the device housing (2) of the first autoinjector and serves as a module adapter for the module housing (17) with the electronic module (16).