WO2024175473A1

WO2024175473A1 - Autoinjector for automatic injection of a product into an injection site

Info

Publication number: WO2024175473A1
Application number: PCT/EP2024/053927
Authority: WO
Inventors: Michael Fiard
Original assignee: Becton Dickinson France SA
Current assignee: Becton Dickinson France SA
Priority date: 2023-02-21
Filing date: 2024-02-15
Publication date: 2024-08-29
Anticipated expiration: 2025-08-21
Also published as: CN120731099A

Abstract

The autoinjector (1) comprises: - a housing receiving a medical container having a needle at its distal end; - a needle cover (200) axially movable inside the housing between a storage position in which it shields the needle, a retracted position in which the needle is uncovered, and a safety position in which the needle is shielded again; - a retainer which is elastically deformable between a rest position in which it maintains a plunger rod in an initial position and a deformed position in which it allows the plunger rod to move distally to push a stopper arranged inside the barrel; - a blocking member (400) rotatable inside the housing about the axis (A1) between a blocking position, in which the it holds the retainer in the rest position, and a release position, in which it allows the deformation of the retainer, said rotation of the blocking member being caused by the needle cover moving from the storage position to the retracted position. The blocking member includes a locking device (450) configured to lock the needle cover (200) in the safety position.

Description

Autoinjector for automatic injection of a product into an injection site

The invention relates to an autoinjector.

In this application, the distal end of a component or of a device is to be understood as meaning the end furthest from the user's hand and the proximal end is to be understood as meaning the end closest to the user's hand. Likewise, in this application, the terms “distal direction” or “distally” are to be understood as meaning the direction away from the user's hand, and the terms “proximal direction” or “proximally” are to be understood as meaning the direction toward the user's hand.

An autoinjector - or automatic injection device - is designed for automatic injection of a medical product into an injection site. An autoinjector usually comprises a housing for receiving a medical container. The medical container has a barrel defining a reservoir for containing the medical product, the barrel having a distal end provided with an injection needle and an open proximal end.

An autoinjector also includes a safety shield movable between an extended and a retracted position to respectively cover or uncover the needle, and an injection mechanism for automatically injecting the medical product into the injection site. The injection mechanism usually includes a plunger rod received in the open proximal end of the barrel for pushing a stopper inside the barrel of the medical container, and an initially compressed spring for moving the plunger distallly. Locking means are provided for maintaining the plunger rod in an initial position in which the plunger rod is axially blocked despite the action of the compressed spring. A release member is typically arranged to release the plunger from the locking means and allow the spring to push the plunger rod distallly to perform injection. A predetermined displacement of the safety shield towards the retracted position is required to allow the release member to unlock the locking means and release the plunger rod.

Once injection is completed, the autoinjector is removed from the injection site and the safety shield automatically moves back to an extended position in which the needle is covered.

It is of paramount importance that the needle be covered after injection and remain covered, in order to prevent injuries by the needle and contaminations by the medical product.

Therefore, there is a need for an autoinjector provided with a mechanism for covering the needle that is reliable, while not being too complex, which would mean additional weight and cost.

For that purpose, and according to one aspect, the invention relates to an autoinjector for automatic injection of a product into an injection site, said autoinjector comprising: - a housing having an axis which defines a longitudinal direction, the housing being configured to receive a medical container comprising a barrel defining a reservoir for containing a medical product, said barrel having a distal end provided with a needle and an open proximal end configured to receive a plunger rod for pushing a stopper arranged inside the barrel; an inner sleeve arranged axially inside the housing and secured to the housing;

- a needle cover coupled to said housing, the needle cover being rotationally fixed relative to the housing and axially movable inside said housing between a storage position in which the needle cover projects beyond the housing distal end so as to shield the needle; a retracted position in which the needle cover has moved proximally with respect to the housing from the storage position so as to at least partially uncover the needle; and a safety position in which the needle cover has moved back distally with respect to the housing from the retracted position and projects beyond the housing distal end so as to shield the needle; guide means fixedly arranged on the housing in order to guide the axial movement of the needle cover relative to the housing;

- first biasing means for biasing the needle cover distally;

- a plunger rod axially movable inside the housing between an initial position and an injection end position distally located relative to said initial position, the plunger rod being configured to push the stopper to expel the medical product;

- second biasing means for biasing the plunger rod distally;

- a retainer for maintaining the plunger rod in the initial position against the action of the second biasing means, the retainer being arranged at the distal portion of the inner sleeve, the retainer being elastically deformable between a rest position in which the retainer axially abuts against the plunger rod for blocking the plunger rod in said initial position, and a deformed position in which the retainer is radially deflected to allow the plunger rod to move distally;

- a blocking member arranged inside the housing, said blocking member being axially fixed relative to the housing and rotatable relative to the housing about the axis between a blocking position, in which the blocking member prevents the deformation of the retainer and therefore holds the retainer in the rest position, and a release position, in which the blocking member allows the deformation of the retainer, the rotation of the blocking member from the blocking position to the release position being caused by the needle cover moving from the storage position to the retracted position, the blocking member including a locking device configured to lock the needle cover in the safety position.

Thus, the blocking member performs both an activation function of the injection mechanism, by allowing the retainer to deform and thus the plunger rod to be pushed distally, and a locking function of the needle cover in the safety position. Having these two functions performed by one and a single piece, namely the blocking member, allows reducing the number of parts that constitute the autoinjector, which results in less complexity and material savings. Also, owing to the invention, the autoinjector can have a smaller overall volume, which is significantly advantageous when using smaller medical containers - with a small barrel capacity and/or a short needle - for which conventional bigger autoinjectors designed for bigger medical containers are not necessary. Furthermore, having fewer parts means less dimensional and positioning adjustments between parts, which facilitates the manufacturing process and improves reliability.

In practice, the blocking member and the locking device are preferably formed as a single piece, for example by molding of a plastic material.

The blocking member performs a blocking function not only of the plunger rod in the storage position, but also of the needle cover in the safety position.

In the storage position and the safety position (which can be one and the same position), the needle cover is extended. In the retracted position, which is located proximally relative to the storage position, the needle cover allows injection: thus, said retracted position is determined so that the needle can be inserted into the user’s body at an appropriate depth for injection. Subsequently, the needle cover moves to the safety position, which is located distally relative to the retracted position.

In an embodiment, having the retainer arranged at the distal portion of the inner sleeve entails the blocking member also arranged near said inner sleeve distal portion, insofar as the blocking member is intended to cooperate with the retainer. Furthermore, so that the axial movement of the needle cover can cause the rotation of the blocking member, there is provided a part on the needle cover that is intended to cooperate with the blocking member. Thus, the needle cover needs to extend proximally up to the blocking member. Owing to the invention, as said blocking member is located rather distally inside the housing, which results from the fact that the retainer is arranged at the distal portion of the inner sleeve, the needle cover length can be reduced with respect to prior art autoinjectors in which the retainer is arranged more proximally with respect to the housing.

As a result, the invention allows providing shorter autoinjectors, which is advantageous in terms of storage and transport, and further reduces the amount of material required for manufacturing the autoinjector.

Besides, the autoinjector according to the invention is particularly compact and robust due to at least one of the following features:

- the retainer is arranged on the inner sleeve, which is a piece secured to the housing; - the needle cover can move axially inside the housing but is rotationally fixed relative to the housing, and therefore it is subjected to less constraints;

- the blocking member can rotate relative to the housing but is axially fixed relative to the housing, and therefore it is subjected to less constraints;

The inner sleeve can be made as a single piece with the housing or can be a part of the housing; alternatively, the inner sleeve can be an initially separate piece subsequently secured to the housing. Whatever the embodiment, the inner sleeve is rotationally and slidingly fixed with respect to the housing, about and along the longitudinal direction.

The plunger rod can be arranged inside the inner sleeve and can be axially movable relative to the inner sleeve. Then, the retainer can be outwardly deflectable from its rest position to its deformed position.

In an embodiment, the sole movement of needle cover is the above-described axial movement, and the sole movement of blocking member is the above-described rotational movement.

In an embodiment, no part of the autoinjector other than the needle cover and the blocking member moves relative to the body for the operation of the autoinjector. This does not exclude the provision for parts that do not move, but that deform, such as the retainer and the locking device.

The retainer can be in the form of a leg extending longitudinally.

The retainer can be provided with a holder, such as a bulge, configured for cooperating with the plunger rod. The holder can be located at the distal end of the retainer.

The locking device may comprise a first stop, which preferably extends substantially orthogonally to the axis, for cooperating with the needle cover in the safety position in order to prevent an axial movement of the needle cover in the proximal direction.

In an embodiment, the blocking member comprises a body and the locking device comprises a tab which has a base secured to the body and a free distal end, the tab protruding obliquely from the body, in the distal direction and towards the needle cover (i.e., for example, protruding outwards), the tab being elastically deflectable towards the body by the needle cover moving from the retracted position to the safety position, the distal end of the tab forming said first stop. The body and the tab are preferably made as a single piece.

The locking device may comprise a second stop, which preferably extends in a plane substantially parallel to the axis, for cooperating with the needle cover in the safety position in order to prevent a rotation of the blocking member back towards the blocking position.

In an embodiment, the second stop comprises a wall extending substantially axially and protruding towards the needle cover i.e., for example, protruding outwards. The second stop may be offset from the first stop along the circumferential direction. The blocking member may comprise a cam surface which projects towards the needle cover and which is tilted relative to the axis, said cam surface being configured to cooperate with the needle cover so that the movement of the needle cover from the storage position to the retracted position causes the rotation of the blocking member from the blocking position to the release position.

According to an implementation, the needle cover comprises an operating portion for cooperating with the first stop, and/or the second stop, and/or the cam surface. Said operating portion may thus cause the rotation of the blocking member when the needle cover moves from the storage position to the retracted position, and/or cause the deflection of the tab that forms part of the locking device, when the needle cover moves from the retracted position to the safety position. The operating portion may comprise at least one pin protruding towards the blocking member i.e., for example, protruding inwards.

The retainer may comprise legs provided with a bulge which is oriented towards the plunger rod and which can engage a hole or recess in the plunger rod. Said legs can be elastically deflectable radially away from the plunger rod. The legs may extend axially. They may extend distally from a proximal wall of the housing. The legs may be part of an inner sleeve of the housing, said sleeve protruding distally from the transverse wall which closes the proximal end of the housing.

The blocking member may have an axial groove configured to accommodate the retainer when said retainer is in the deformed position. This axial groove may be offset circumferentially with respect to a blocking surface of the blocking memberthat holds the retainer in the rest position.

The autoinjector may include an axial holder for blocking the blocking member in the axial direction. According to an embodiment of the axial holder, an abutment may be provided inside the housing, preferably in a plane substantially orthogonal to the axis, to prevent proximal movement of the blocking member and a friction of the blocking member peripheral wall against a wall of an adjacent component may provide additional holding force. According to another embodiment of the axial holder, the blocking member may be clipped on the housing or on another component axially secured to the housing, which provides both proximally and distally blocking functions. In this embodiment, there may be provided a hook on the blocking member.

The blocking member may have a plane of symmetry which contains the autoinjector axis.

The blocking member may comprise two sets which are symmetrical relative to a plane which contains the autoinjector axis, each set including a cam surface, a first stop (for example in the form of an elastically deformable tab) and a second stop. For example, the blocking member has a plane of symmetry which contains the autoinjector axis. The blocking member may have a generally cylindrical shape. It may comprise a body which is substantially cylindrical. In an implementation, the blocking member is arranged outside the plunger rod and the retainer, and inside the needle cover. The blocking member may be located proximally from a bearing surface of the autoinjector on which a proximal flange of the medical container barrel can bear.

The needle cover may comprise guide means configured to cooperate with the guide means fixedly arranged on the housing, whereby the axial movement of the needle cover relative to the housing is guided and, preferably, the radial or tangential movement of the needle cover relative to the housing is limited or even prevented.

Guide means may also be arranged on the blocking member, for cooperating with the needle cover guide means.

For example, the needle cover has a distal portion comprising a shielding portion, said shielding portion being substantially cylindrical, and at least one arm that extends proximally from the shielding portion. The needle cover preferably comprises two arms that are diametrically opposed. The operating portion may be located near the proximal end of the or each arm.

The housing may comprise a channel that extends axially and receives the needle cover arm, at least part of the side ends of the arm being located in abutment with an inner surface of the channel. By “in abutment with” is meant in contact, or in close proximity with a possible functional gap for allowing a relative sliding movement parallel to the axis.

Preferably, at least part of the side ends of the arm are located in abutment with two substantially orthogonal inner faces of the channel, in order to prevent movement along two orthogonal directions.

In an embodiment, a first part of the side end of the arm is in contact with one inner face of the channel, and a second part of the side end of the arm, at an axial location that is different from the one of the first part, is in contact with another inner face of the channel. The guiding may be achieved along the length of the arm at different locations, by different features or cooperation of features. For example, at one axial location, there is provided a guiding to prevent tangential movement, at another axial location there is provided a guiding to prevent radial movement inwards, and at still another axial location, there is provided a guiding to prevent radial movement outwards.

The needle cover arm may have a main wall and may comprise at least one rail that extends axially and protrudes outwards from said main wall. Said rail can be configured to be in abutment with an inner peripheral wall of the housing. This implementation allows preventing an outward movement of the needle cover. In addition or in a variant, said rail can be configured to be in abutment with at least one rib that protrudes inwards from the housing and extends axially. This implementation allows preventing a tangential movement of the needle cover. One and the same rail can be in abutment with both the inner peripheral wall of the housing and the rib or, alternatively, distinct rails may be provided for these two functions.

The needle cover arm may comprise a tab which has a base secured to the arm main wall and a free distal end, the tab protruding obliquely from the main wall, in the distal direction and towards the housing, the tab being elastically deflectable towards the axis to allow mounting the needle cover in the housing. Furthermore, in the storage position and the safety position, the distal end of the tab can be configured to be in abutment with at least one rib that protrudes inwards from the housing and extends axially, in order to prevent the needle cover from moving distally with respect to the housing. Said rib can be the same as the one cooperating with the needle cover rail, or a distinct rib.

As the rail is in abutment with the inner peripheral wall of the housing, said main wall is depressed radially inwards with respect to the inner peripheral wall of the housing. Thus, a volume is created between the main wall of the needle cover arm and the inner peripheral wall of the housing. The tab can be located in said volume.

In the storage position, part of the side ends of the arm can be in abutment with a face of the blocking member that extends in a plane substantially parallel to the axis. This contributes to holding the needle cover arm in an appropriate position when the needle cover is in the storage position, by preventing an unintended tangential displacement. This ensures that the successive movements of the autoinjector components are carried out appropriately for the correct operation of the autoinjector.

In an embodiment, the blocking member comprises a body which includes:

- a central bore in which the inner sleeve is received, the central bore having an inner face, which is for example substantially cylindrical;

- at least one axial groove which opens in said central bore; wherein, in the blocking position, the blocking member is positioned such that the retainer radially faces the inner face of the central bore and, in the release position, the blocking member is positioned such that the retainer radially faces the axial groove.

The axial groove can be configured to allow the deformation of the retainer to start when the needle cover has moved axially along a predetermined length and, preferably, to control the deformation speed of the retainer towards its deformed position. These effects can be obtained in particular thanks to the circumferential location of the axial groove and/or its shape.

The start of the retainer deformation almost immediately entails the start of the injection. Allowing the deformation of the retainer to start when the needle cover has moved axially along a predetermined length amounts to setting the beginning of the injection with respect to the pricking depth. It may be advantageous to begin injection before the needle has reached its final pricking depth, to ensure that all the medical product will be expelled from the medical container and injected into the injection site when the user removes the autoinjector from said injection site.

For example, in an embodiment, the retainer can be allowed to deform after the blocking member has rotated over an angle of 22°, which corresponds to an axial movement of the needle cover of about 5 mm.

Controlling the deformation speed of the retainer towards its deformed position allows controlling the operation of the plunger rod during the time period between the moment at which the retainer release is initiated and the moment at which the plunger rod is free to move distally to actually perform injection.

It may be preferable that this time period is fairly short, while not being too short, which might lead to a shock felt by the user. Besides, some constraints may limit the speed that can be achieved, such as autoinjector assembling considerations.

For example, a longitudinal edge between the inner face and the axial groove is the last contact portion between the retainer and the inner face before the retainer is allowed to deform following the rotation of the blocking member, said longitudinal edge being called activation edge.

In an embodiment, the axial groove comprises a control face which extends from the activation edge towards the inner space of said axial groove (i.e. away from the inner face) and away from the housing axis, said control face being inclined relative to a radial segment of the housing passing through the activation edge by an angle comprised between 25° and 50°, preferably between 35° and 45°. Said angle is viewed in a plane orthogonal to the housing axis.

Such an angle needs to be high enough to provide a control face that has a slope steep enough to cause a quick deformation of the retainer and thus a quick release of the plunger rod, meaning a quick actual start of the injection. However, too high an angle may lead to a too sudden movement which may cause shocks and harm the proper functioning of the autoinjector. Besides, too high an angle may lead to difficulties or even impossibilities to have the various parts of the autoinjector properly assembled.

According to a second aspect, the invention relates to a medical device comprising an autoinjector as previously described and a medical container comprising a barrel defining a reservoir for containing a medical product, said barrel having a distal end provided with a needle and an open proximal end configured to receive a plunger rod for pushing a stopper arranged inside the barrel, said medical container being received in the housing of the autoinjector.

According to a third aspect, the invention relates to an autoinjector for automatic injection of a product into an injection site, said autoinjector comprising:

- a housing having an axis which defines a longitudinal direction, the housing being configured to receive a medical container comprising a barrel defining a reservoir for containing a medical product, said barrel having a distal end provided with a needle and an open proximal end configured to receive a plunger rod for pushing a stopper arranged inside the barrel;

- a needle cover coupled to and axially movable inside said housing between a storage position in which the needle cover projects beyond the housing distal end so as to shield the needle; a retracted position in which the needle cover has moved proximally with respect to the housing from the storage position so as to at least partially uncover the needle; and a safety position in which the needle cover has moved back distally with respect to the housing from the retracted position and projects beyond the housing distal end so as to shield the needle;

- first biasing means for biasing the needle cover distally;

- second biasing means for biasing the plunger rod distally;

- a retainer for maintaining the plunger rod in the initial position against the action of the second biasing means, the retainer being configured to be either in an engaged state in which the retainer maintains the plunger rod in said initial position, and an unengaged state in which the retainer allows the plunger rod to move distally;

- a blocking member arranged and movable inside the housing between a blocking position, in which the blocking member holds the retainer in the engaged position, and a release position, in which the retainer is free to move towards its unengaged state , the movement of the blocking member from the blocking position to the release position being caused by the needle cover moving from the storage position to the retracted position; wherein the needle cover comprises a shielding portion at its distal end, configured to cover the needle in the storage position and in the safety position, and an inner portion which extends proximally from the shielding portion, inside the housing, the inner portion having a main wall and a stop that protrudes outwards from said main wall, wherein, in the storage position and the safety position, the stop is configured to be in abutment with at least one rib that protrudes inwards from the housing and extends axially, in order to prevent the needle cover from moving distally with respect to the housing, from the storage position or from the safety position.

Such an arrangement allows efficiently holding the needle cover with respect to the housing during a drop test of the autoinjector, and therefore ensure robustness and proper operation of said autoinjector.

Furthermore, having the needle cover in direct abutment with the housing, with no intermediate part, makes the autoinjector design simpler and allows material savings. A direct contact between the needle cover and the housing also means less dimensional and positioning adjustments between parts, which facilitates the manufacturing process and improves reliability. In an embodiment, the inner portion of needle cover comprises a tab which has a base secured to the main wall and a free distal end, the tab protruding obliquely from the main wall, in the distal direction and towards the housing, the tab being elastically deflectable towards the axis to allow mounting the needle cover in the housing, the distal end of the tab forming said stop.

The inner portion of needle cover may further comprise at least one rail that extends axially and protrudes outwards from said main wall, said rail being configured to be in abutment with an inner peripheral wall of the housing.

The tab may be accommodated in the area formed between the main wall of the inner portion of the needle cover and the inner peripheral wall of the housing, as a result of the existence of the rail.

The shielding portion may be substantially cylindrical. The inner portion may comprise at least one arm, preferably two arms that are diametrically opposed.

The inner portion of the needle cover may allow guiding needle cover axial movement, to limit or prevent the radial or tangential movement of the needle cover relative to the housing.

The inner portion may also comprise an operating portion for cooperating with the blocking member to cause the movement of said blocking member and/or to lock the needle cover in the safety position.

The autoinjector may also have one of the previously described features, taken along or in combination. In particular, the retainer may be elastically deformable between the engaged state - also called rest position - in which the retainer axially abuts against the plunger rod for blocking the plunger rod in said initial position, and the unengaged state - also called deformed position - in which the retainer is radially deflected to allow the plunger rod to move distally. The blocking member may be rotatable about the axis between the blocking position and a release position; in case the retainer is deformable as mentioned above, the blocking member when in the blocking position may prevent the deformation of the retainer and therefore hold the retainer in the rest position. Besides, the blocking member may include a locking device configured to lock the needle cover in the safety position.

According to a fourth aspect, the invention relates to an autoinjector for automatic injection of a product into an injection site, said autoinjector comprising:

- a housing having an axis which defines a longitudinal direction, the housing being configured to receive a medical container comprising a barrel defining a reservoir for containing a medical product, said barrel having a distal end provided with a needle and an open proximal end configured to receive a plunger rod for pushing a stopper arranged inside the barrel; - a needle cover coupled to and axially movable inside said housing between a storage position in which the needle cover projects beyond the housing distal end so as to shield the needle; a retracted position in which the needle cover has moved proximally with respect to the housing from the storage position so as to at least partially uncover the needle; and a safety position in which the needle cover has moved back distally with respect to the housing from the retracted position and projects beyond the housing distal end so as to shield the needle;

- first biasing means for biasing the needle cover distally;

- second biasing means for biasing the plunger rod distally;

- a retainer for maintaining the plunger rod in the initial position against the action of the second biasing means, the retainer being elastically deformable between a rest position in which the retainer axially abuts against the plunger rod for blocking the plunger rod in said initial position, and a deformed position in which the retainer is radially deflected to allow the plunger rod to move distally;

- a blocking member arranged inside the housing, said blocking member being rotatable about the axis between a blocking position, in which the blocking member prevents the deformation of the retainer and therefore holds the retainer in the rest position, and a release position, in which the blocking member allows the deformation of the retainer, the rotation of the blocking member from the blocking position to the release position being caused by the needle cover moving from the storage position to the retracted position, the blocking member including a locking device configured to lock the needle cover in the safety position, wherein the blocking member comprises a body which includes a central bore having an inner face and at least one axial groove which opens in said central bore and wherein, in the blocking position, the blocking member is positioned such that the retainer radially faces the inner face of the central bore and, in the release position, the blocking member is positioned such that the retainer radially faces the axial groove.

In an embodiment, the axial groove is configured to allow the deformation of the retainer to start when the needle cover has moved axially along a predetermined length and, preferably, to control the deformation speed of the retainer towards its deformed position.

In an embodiment, the axial groove comprises a control face which extends from the activation edge towards the inner space of said axial groove (i.e. away from the inner face) and away from the housing axis, said control face being inclined relative to a radial segment of the housing passing through the activation edge by an angle comprised between 25° and 50°, preferably between 35° and 45°. The autoinjector may further comprise an inner sleeve arranged axially inside the housing and secured to the housing the inner sleeve being received in central bore of blocking member. The retainer can be arranged at the distal portion of the inner sleeve.

The autoinjector may also have one of the previously described features, taken along or in combination.

A possible embodiment of the invention will now be described by way of nonlimiting examples with reference to the appended figures:

Figure 1 shows a medical device comprising an autoinjector according to an embodiment of the invention, in a storage position,

Figure 2 shows a medical container to be received to the autoinjector,

Figure 3 is an exploded view of the autoinjector,

Figure 4 is a perspective view, from a side, of a top housing pertaining to a housing of the autoinjector,

Figure 5 is a perspective view, from a distal end, of the top housing of figure 4,

Figure 6 is a perspective view, from a side, of a bottom housing pertaining to a housing of the autoinjector,

Figure 7 is a perspective view, from a distal end, of the bottom housing of figure 6, Figure 8 is a partial perspective view, from a proximal end, of the bottom housing of figure 6,

Figure 9 is a perspective view of a top plunger rod of the autoinjector,

Figure 10 is a perspective view, from a side, of a needle cover of the autoinjector, Figure 11 is a perspective view, from a distal end, of the needle cover of figure 10, Figure 12 is a perspective view, from a side, of a blocking member of the autoinjector,

Figure 13 is a perspective view, from a proximal end, of the blocking member of figure 12,

Figure 14 is a detailed cross-section view of the blocking member of figure 12,

Figures 15 and 16 are perspective views of a cap of the autoinjector,

Figures 17 and 18 are longitudinal cross-section views of the autoinjector in the storage position, in two planes which are orthogonal to each other,

Figure 19 is a bottom view of the autoinjector in the storage position,

Figure 20 is a partial perspective view of the autoinjector in the storage position, Figures 21 , 22, 23 and 24 are transverse cross-section views of the autoinjector in the storage position, according to lines A-A, B-B, C-C and D-D of Figure 1 , respectively,

Figure 25 is a partial perspective view of the autoinjector in the storage position, from the distal end, Figure 26 is a transverse cross-section view of the autoinjector in the storage position, with the blocking member in a blocking position,

Figures 27 and 28 are partial longitudinal cross-section views of the autoinjector showing steps of its use, from the storage position,

Figure 29 is a partial side view of the autoinjector showing the movement of the blocking member from the blocking position to a release position,

Figure 30 is a schematic view similar to Figure 26 when the blocking member is in its release position,

Figure 31 is a view similarto Figure 17 with the needle cover in a retracted position, before injection,

Figure 32 is a view similar to Figure 31 , once injection is completed,

Figure 33 is a partial side view of the autoinjector showing the blocking member in the release position and the movement of the needle cover from the retracted position to a safety position,

Figure 34 is a view similarto Figure 18, with the needle cover in the safety position,

Figure 35 is a partial perspective view of an autoinjector according to another embodiment of the invention, in the storage position,

Figure 36 is a longitudinal cross-section view of the autoinjector of figure 35;

Figure 37 is a partly cut-away perspective view of the top housing of figure 4;

Figure 38 is a perspective view of a top housing pertaining to the autoinjector of figure 35,

Figure 39 is a transverse cross-section view of the autoinjector in which the blocking member has rotated from its blocking position while still holding the retainer in the rest position,

Figure 40 is a transverse cross-section view of the autoinjector in which the blocking member has rotated from its blocking position and is about to allow the deformation of the retainer.

Figure 1 shows an autoinjector 1 according to an embodiment of the invention.

The autoinjector 1 is designed for automatic injection of a product into an injection site. The autoinjector 1 extends along an axis A1 which defines a longitudinal direction, and which is also the axis of the components of the autoinjector 1 in the mounted position.

As shown in figure 3, the autoinjector 1 comprises various components including a housing 100, a needle cover 200, a plunger rod 300, and a blocking member 400.

The housing 100, which has an axis A100 extending longitudinally, is configured to receive a medical container 2 illustrated in figure 3. The medical container 2 has an axis A2 and comprises a barrel 3 defining a reservoir for containing a medical product. The barrel 3 has a distal end 4 provided with a needle 5 (also called injection needle) and a proximal end 6 which is open and configured to receive the plunger rod 300. A stopper 7 is arranged inside the barrel 3 (see figure 17 for example), proximally from the medical product, and is intended to be pushed by the plunger rod 300 to discharge the medical product through the needle 5. The medical container 2 also comprises a flange 8 extending outwards from the proximal end 6. A rigid needle shield 9 is removably attached to the barrel 3 for covering the needle 5 before use.

The housing 100 is illustrated in figures 4 to 8.

The housing 100 has two planes of symmetry P1 and P2 which both comprise axis A100 and which are mutually orthogonal.

The housing 100 may include a bottom housing 101 having an axis A101 and a top housing 150 having an axis A150 which are assembled to each other by any appropriate securing means such as, for instance, snap-fitting means. The bottom housing 101 and the top housing 150 may have corresponding cylindrical shapes such that, when they are assembled, they substantially form a cylinder in which axes A101 , A150 and A100 are substantially one and the same. Also, preferably, the bottom housing 101 and the top housing 150 both have two planes of symmetry which, in the mounted position, coincide with planes P1 and P2. Therefore, the same references P1 , P2 are used to identify the planes of symmetry of the bottom housing 101 and the top housing 150.

The bottom housing 101 is described with reference to figures 6 to 8.

The bottom housing 101 may be realized as a single piece, for example by injection molding of a plastic material.

The bottom housing 101 comprises a peripheral wall 102 which is preferably substantially cylindrical and which has an inner face 103, an outer face 104, an open distal end 105 and an open proximal end 106. The bottom housing 101 may also comprise an inner sheath 107 which is substantially cylindrical and coaxial with the peripheral wall 102. The open distal end 108 of the sheath 107 may be located proximally from the open distal end 105 of the peripheral wall 102 and the open proximal end 109 of the sheath 107 may be located distally from the open proximal end 106 of the peripheral wall 102.

In an embodiment, on both sides of axis A101 , a partition wall 110 extends substantially parallel to plane P2 substantially from the sheath distal end 108 to the sheath proximal end 109. Said partition wall 110 can be nearly tangential to the sheath 107 while possibly slightly offset relative to said sheath 107 towards the axis A101. The longitudinal edges 111 of the partition wall 110 can be directly linked to the inner face 103 of the bottom housing peripheral wall 102 (see figures 7 and 23), except near the sheath proximal end 109, where each of said longitudinal edges 111 can be spaced from said inner face 103 and extended by a side wall 1 12 which has at least a portion orthogonal to the partition wall 1 10 and which is linked to the inner face 103 of the bottom housing peripheral wall 102 (see figures 8, 20 and 22).

Two channels 115 are thus formed between the sheath 107 and the peripheral wall 102. The channels 115 extend axially along the whole sheath 107. The channels 115 are symmetrical to one another with respect to plane P2, and each channel is symmetrical with respect to plane P1 . Each channel 115 has an inner surface 1 16 which is formed of successive faces formed by the bottom housing peripheral wall 102, the partition wall 110, possibly the sheath 107, and the side wall 112 where present.

The sheath 107 is attached to the peripheral wall 102 by the partition wall 111 , and preferably furthermore by a first transverse wall 117 close to the sheath distal end 108 and by a second transverse wall 118 close to the sheath proximal end 109. Said first and second transverse walls 117, 118 preferably extend over the ring-shaped cross-section area between the sheath 107 and the peripheral wall 102 except for the cross-section area which correspond to the channels 115.

In an embodiment, a window 119 extends through the bottom housing 101 , parallel to plane P2. The window 119 may form a substantially rectangular border on opposite sides of the bottom housing peripheral wall 102. Said window 119 is intended for allowing inspection of the medical container 2 received in the autoinjector 1 .

The proximal part of the peripheral wall 102 may be provided with two notches 120 which face each other along a direction orthogonal to P1 , each notch 120 being symmetrical with respect to P2. Each notch 120 may be square-shaped, with a bottom face substantially level with the second transverse wall 118 and two longitudinal side edges 121. As shown in figures 6, 8 and 22, proximally from the second transverse wall 118, the peripheral wall 102 may extend circumferentially beyond the side wall 112 of the channel 115, thereby forming a lip 122.

Facing each notch 120 can be provided a snap-fitting protuberance 123 which protrudes outwards from the sheath 107. Preferably, the snap-fitting protuberance 123 does not extend radially beyond the cylindrical envelope formed by the bottom housing peripheral wall 102.

The bottom housing 101 may further comprise at least one rib 124 that protrudes inwards from the peripheral wall 102 and extends axially. The rib 124 may extend from the peripheral wall open distal end 105, the proximal face 125 of the rib 124 being spaced apart from the inner sheath distal end 108. The rib 124 may protrude from the peripheral wall 102 along a direction that is substantially parallel to P1 .

For example, the bottom housing 101 comprises two sets 126 of two ribs 124, the sets being arranged symmetrically with respect to plane P2. In each set 126, the ribs 124 may be arranged symmetrically with respect to plane P1 and may be adjacent. For example, viewed in a plane orthogonal to axis A101 , the distance between the ribs 124 may be substantially identical to the width of each rib 124.

The top housing 150 is now described with reference to figures 4 and 5.

The top housing 150 may be realized as a single piece, for example by injection molding of a plastic material.

The top housing 150 comprises a peripheral wall 152 which is preferably substantially cylindrical and which has an inner face 153, an outer face 154, an open distal end 155 and a proximal end closed by a proximal transverse wall 156.

The distal part of the peripheral wall 152 may be provided with two notches 159 which face each other along a direction orthogonal to P2, each notch 159 being symmetrical with respect to P1. Between the notches 159 are thus formed two projections 160 which are configured to cooperate with the notches 120 of the bottom housing 101. In order to have a housing 100 which a continuous peripheral wall, the shape of the projections 160 preferably matches the shape of the notches 120. Thus, each projection 160 may be square-shaped, with two longitudinal side edges 161 . Furthermore, a lip 162 may extend circumferentially beyond each longitudinal side edge 161 , while being offset inwards, as shown in figures 5 and 22. The lip 162 of the top housing 150 is intended to cooperate radially with the inner face of the lip 122 of the bottom housing 101 , to ensure proper positioning and attachment of the top housing 150 and the bottom housing 101. In addition, a hole 163 may be provided in each projection 160, for receiving the snap-fitting protuberance 123 and provide a secure connection between the top housing 150 and the bottom housing 101.

The top housing 150 may further comprise at least one rib 164 that protrudes inwards from the peripheral wall 152 and extends axially. The rib 164 may protrude from the peripheral wall 152 along a direction that is substantially parallel to P1. For example, the top housing 150 comprises two sets 166 of two ribs 164, the sets being arranged symmetrically with respect to plane P2. In each set 166, the ribs 164 may be arranged symmetrically with respect to plane P1 and may be close to each other. In an example, viewed in a plane orthogonal to axis A150, the width of a set 166 of ribs 164 is substantially identical to the width of a set 126 of ribs 124 of the bottom housing 101. Each rib 164 may extend from the proximal transverse wall 156 distally substantially up to the proximal edge 158 of the corresponding notch 159.

As best seen in figure 37, the top housing 150 may also comprise an inner sleeve 167 which is substantially cylindrical and coaxial with the peripheral wall 152.The sleeve 167 may extend from the proximal transverse wall 156, and the open distal end 168 of the sleeve 167 may be located proximally from the proximal edge 158 of the notch 159. The diameter of the sleeve 167 may be smaller than the diameter of the sheath 107. In an embodiment, the distal portion of the sleeve 167 is provided with indentations 169 that extend axially from the open distal end 168 of the sleeve 167. Therefore, between two indentations 169 is formed a leg 170 that extends axially. Said leg can be provided with a bulge 171 , preferably at its distal end, said bulge 171 being oriented towards the axis A150. The leg 170 can be elastically deflectable radially outwards from a rest position (illustrated in figure 5 and in figure 31 in solid line) towards a deformed position (illustrated in figure 31 in dotted line). As will be explained, the leg 170 form a retainer. There may be provided two legs 170 arranged symmetrically with respect to plane P1 .

An elongated protrusion 175 which protrudes distally from the proximal transverse wall 156 extends in the sleeve 167, orthogonally to plane P2. The elongated protrusion 175 has a small height along axis A150. In particular, it is offset proximally with respect to the indentations 169.

Besides, the top housing 150 may comprise four ribs 176 which protrude distally from the proximal transverse wall 156 and which each connects the peripheral wall 152 to the sleeve 167. The ribs 176 may be arranged at 90° apart from one another, each rib 176 being substantially included in one of planes P1 and P2.

It is now referred to figure 9 which illustrates the plunger rod 300. The plunger rod 300 is intended to be mounted in the housing 100, for example in the top housing 150. The plunger rod 300 has a cylindrical wall 301 having an axis A300 which is substantially coincident with the autoinjector axis A1 in the mounted position. Preferably, the plunger rod 300 has two planes of symmetry which, in the mounted position, coincide with planes P1 and P2. Therefore, the same references P1 , P2 are used to identify the planes of symmetry of the plunger rod 300.

At its distal end 305, the plunger rod 300 comprises a collar 302 extending in a plane orthogonal to axis A300 and oriented inwards, the collar 302 defining an opening 303. The proximal end 306 of the plunger rod 300 is open. The cylindrical wall 301 comprises indentations 304 that extend axially from the proximal end 306 and that are configured to receive the elongated protrusion 175 of the top housing 150, in orderto prevent the plunger rod 300 from rotating about axis A150 relative to the top housing 150. Thus, in the previously described embodiment, the indentations 304 face each other along a direction orthogonal to P2, each indentation 304 being symmetrical with respect to P1 .

The cylindrical wall 301 also comprises at least one hole 310 for receiving the bulge 171 of one leg 170 of the top housing 150. Thus, in the previously described embodiment where the top housing 150 comprises two legs 170, there are provided two holes 310 which face each other along a direction orthogonal to P1 , each hole 310 being symmetrical with respect to P2.

The needle cover 200 is now described with reference to figures 10 and 11 . The needle cover 200 is intended to be mounted in the housing 100. The needle cover 200 has an axis A200 which is substantially coincident with the autoinjector axis A1 in the mounted position. Preferably, the needle cover 200 has two planes of symmetry which, in the mounted position, coincide with planes P1 and P2. Therefore, the same references P1 , P2 are used to identify the planes of symmetry of the needle cover 200.

The distal portion of the needle cover 200 forms a shielding portion 201 which has a substantially cylindrical peripheral wall 202 and which is intended to cover the needle 5 in order to prevent injuries and contaminations. Said peripheral wall 202 has an inner face 203 and an outer face 204. The distal end 205 of the needle cover 200 comprises a bearing surface 207 that extends in a plane orthogonal to axis A200. Said bearing surface 207 has a portion which extends inwards from the peripheral wall 202 and which has a central opening 208, and a portion which extends outwards and forms an annular flange 209. At the proximal end of the shielding portion 201 is also arranged an annular flange 210 that extends outwards from the peripheral wall 202. Both flanges 209, 210 may have substantially the same outer diameter.

The needle cover 200 further comprises at least one arm 220 that extends proximally from the shielding portion 201. In the embodiment illustrated in figure 10, the needle cover 200 comprises two arms 220 arranged symmetrically with respect to plane P2. Preferably, the or each arm 220 is symmetrical with respect to plane P1 .

The arm 220 comprises a main wall 221 which has a curved section - when viewed along axis A200 - that follows the cylindrical shape of the shielding portion peripheral wall 202. A distal part 222 of the main wall 221 has longitudinal edges 223 and is extended by a proximal part 224 which has longitudinal edges 225 closer to each other than the longitudinal edges 223 of the distal part 222. In other words, the width of the distal part 222 is larger than the width of the proximal part 224, when the needle cover 200 is viewed along a direction that is orthogonal to plane P2. As a result, a transverse edge 226 is formed between the distal part 222 and the proximal part 224. The proximal end 206 of the needle cover 200 is also the proximal end of the arms 220.

The arm 220 further comprises at least one rail 230 that extends axially and protrudes outwards from the main wall 221 . In an embodiment, each arm 220 comprises two rails 230. The rails 230 can be arranged at the longitudinal edges 225 of the main wall proximal part 224. Preferably, the rails 230 define an outer diameter of the needle cover 200 around the arms 220 that is substantially identical to the outer diameter of the needle cover 200 around the shielding portion 201 . For example, the rails 230 and the annular flange 210 at the proximal end of the shielding portion 201 may form a continuous rib.

The needle cover 200 also comprises a pin 235 that protrudes from the arm 220 towards the axis A200. The pin 235 is for example located at the main wall proximal part 224, close to the proximal end 206. Preferably, the proximal surface 236 of the pin 235 is substantially orthogonal to the axis A200 while the distal surface 237 can be tilted.

The needle cover 200 further comprises a tab 240 arranged on each arm 220. The tab 240 has a base 241 secured to the arm main wall 221 , preferably between the rails 230, and a free distal end 242 that extends preferably orthogonally to axis A200. The tab 240 protrudes obliquely from the main wall 221 , distally and outwards. More specifically, for example and as seen in figures 10 and 18, the tab 240 may have an inner face 243 that is level with the inner face of the arm main wall 221 , and an outer face comprising a ramped portion 244 that is tilted distally and outwards and a straight portion 245 that is substantially parallel to the outer face of the main wall 221 but offset outwards with respect to said outer face of the main wall 221 .

From the above-described position, the tab 240 may be elastically deflectable towards the axis A200 to allow mounting the needle cover in the housing 100.

The blocking member 400 is now described with reference to figures 12 to 14.

The blocking member 400 is intended to be mounted in the housing 100. The blocking member 400 has an axis A400 which is substantially coincident with the autoinjector axis A1 in the mounted position. Preferably, the blocking member 400 has a plane of symmetry P which contains the autoinjector axis A1 in the mounted position.

The blocking member 400 comprises a body 401 which has a generally cylindrical shape. The outer face of the body 401 has two portions 402 which have a cylindrical shape bounded by longitudinal edges 403. Said portions 402 - called cylindrical portions 402 - are arranged symmetrically with respect to the axis A400, each portion 402 being symmetrical with respect to plane P. Between the cylindrical portions 402, the outer face of the body 401 has a portion 404 which is recessed inwards with respect to the cylindrical portions 402. Thus, the outer face of the body 401 has two recessed portions 404. Each recessed portion 404 has an outer face 407 that may be substantially cylindrical.

The blocking member 400 has a central bore 410 which extends axially and which has the same diameter as the inner diameter of the recessed portions 404. Two facing axial grooves 411 open in said central bore 410. Each axial groove 411 is arranged in the same angular sector as a corresponding cylindrical portion 402, on the inner side thereof. The blocking member 400 has an open distal end 405 and an open proximal end 406. At said proximal end 406, a transverse wall 408 extends from the periphery of the body 401 to the border of the opening formed by the combination of the bore 410 and the grooves 411. Opposite the recessed portions 404 in the radial direction, i.e. circumferentially apart from the axial grooves 411 , the central bore 410 has an inner face 413 that is substantially cylindrical.

The blocking member 400 may comprise a tilted rib 435 which protrudes outwards from the recessed portion outer face 407. The tilted rib 435 has a distal end 431 which may be located close to the blocking member distal end 405 and to one longitudinal edge 403 and a proximal end 432 which may be located close to the blocking member proximal end 406 and away from said longitudinal edge 403. The distal face 436 of the tilted rib 435 thus forms a cam surface which is tilted relative to the axis A400 and defines a tilted or substantially helical path from the distal end 431 towards the proximal end 432. The tilted rib 435 may form an angle a comprised between 20° and 45° with respect to axis A400, when viewed orthogonally to axis A400, as shown in figure 33.

A longitudinal rib 437 protruding outwards from the recessed portion outer face 407 and extending axially is arranged - along the circumferential direction - between the proximal end 432 of the tilted rib 435 and the longitudinal edge 403 which faces the longitudinal edge 403 close to the distal end 431 of the tilted rib 435.

In an example, the blocking member 400 further comprises an abutment wall 438 which protrudes outwards from the recessed portion outer face 407. The abutment wall 438 extends substantially axially from the blocking member distal end 405, the proximal end of said abutment wall 438 being spaced apart from the tilted rib 435, along a direction parallel to axis A400. The abutment wall 438 is located - along the circumferential direction - between the distal end 431 of the tilted rib 435 and the longitudinal rib 437. A distal rib 439 protruding outwards from the recessed portion outer face 407 may follow the blocking member distal end 405 to join the abutment wall 438 and the longitudinal rib 437.

The blocking member 400 may further comprise a tab 440 located in the recessed portion 404, between the abutment wall 438 and the longitudinal rib 437, and between the tilted rib 435 and the blocking member distal end 405 or the distal rib 439 when present. The tab 440 has a base 441 secured to the body 401 of the blocking member 400, and a free distal end 442 that extends preferably orthogonally to axis A400. The tab 440 protrudes obliquely from the body 401 , distally and outwards. More specifically, for example and as seen in figures 12 and 14, the tab 440 may have an outer face comprising a ramped portion 444 that is tilted distally and outwards and a straight portion 445 that is substantially parallel to the recessed portion outer face 407 but offset outwards with respect to said outer face 40. From the above-described position, the tab 440 may be elastically deflectable towards the axis A400.

The tab 440, abutment wall 438 and distal rib 439 are part of a locking device 440 of the blocking member 400, said locking device 440 being configured to lock the needle cover 200 in a safety position, as will be explained onwards.

In an embodiment, the autoinjector 1 also comprises a cap 500 that is now described with reference to figures 15 and 16.

The cap 500 may be realized as a single piece, for example by injection molding of a plastic material. The cap 500 is intended to be mounted at the distal end of the housing 100. The cap 500 has an axis A500 which is substantially coincident with the autoinjector axis A1 in the mounted position. Preferably, the cap 500 has two planes of symmetry which, in the mounted position, coincide with planes P1 and P2. Therefore, the same references P1 , P2 are used to identify the planes of symmetry of the cap 500.

The cap 500 comprises a peripheral wall 502 which is preferably substantially cylindrical and which has an inner face 503, an outer face 504, an open proximal end 506 and a distal end closed by a transverse wall 505. The outer face 504 may be provided with beads 501 or equivalent for preventing the user’s fingers to slip on the peripheral wall 502 when removing the cap 500.

The cap 500 may comprise at least one protrusion 507 which protrudes towards the axis A500 from the peripheral wall inner face 503, at a distance from both the transverse wall 505 and the proximal end 506, along a direction that is orthogonal to plane P1. Preferably, there are provided two protrusion 507 which are diametrically opposed and arranged symmetrically with respect to plane P1 .

The cap 500 may also comprise at least one rib 508 that protrudes inwards from the peripheral wall 502 and extends axially. The rib 508 may extend from the transverse wall 505, the proximal face 509 of the rib 508 being spaced apart from the proximal end 506. Preferably, the cap 500 comprises several such ribs 508, such as four ribs 508 arranged at 90° apart from one another, each rib 508 being substantially included in one of planes P1 and P2.

In an embodiment, an inner ring 510 protrudes from the transverse wall 505 coaxially with axis A 500. From said inner ring 510 extend two legs 520 arranged symmetrically with respect to plane P2, each leg 520 being symmetrical with respect to plane P1 . Each leg 520 extends axially and has the curved profile of a portion of a cylinder that follows the shape of the inner ring 510. The proximal end of the legs 520 is located proximally from the proximal end 506 of the peripheral wall 502. The proximal end of each leg 520 can be provided with a bulge 521 , said bulge 511 being oriented towards the axis A500. The legs 520 are preferably elastically deflectable radially outwards from a rest position illustrated in figures 15 and 16.

The autoinjector 1 in a storage position, i.e. a position in which it is packaged, stored and sold to a user, before use, is illustrated in figures 1 , and 17 to 28 and will now be described.

The medical container 2, equipped with the rigid needle shield 9, is engaged in the sheath 107 of the bottom housing 101 , with the flange 8 bearing on the proximal end 109 of the sheath 107, as shown in figure 20.

The needle cover 200 is mounted in the bottom housing 101 , the arms 220 being received in the channels 115 and extending proximally beyond the proximal end 106 of the bottom housing peripheral wall 102, so that the pin 235 is located proximally beyond said proximal end 106. The needle cover 200 is therefore located between the sheath 107 and the bottom housing peripheral wall 102. Then, the needle 5 extends distally beyond the bottom housing proximal end 105, as can be seen in figure 18. The annular flange 210 of the needle cover shielding portion 201 provides centering with respect to the bottom housing peripheral wall 102, as shown in figure 17.

Once in the mounted position, in the storage position, the needle cover 200 is prevented from moving distally with respect to the housing 100 owing to the snap-fitting engagement between the needle cover 200 and the bottom housing 101. More specifically, the distal end 242 of the tabs 240 abuts the proximal face 125 of the ribs 124 of the bottom housing 101 , as shown in figure 18.

Moreover, the needle cover 200 is prevented from rotating about axis A1 with respect to the housing 100 and the arms 220 are prevented from moving tangentially and radially with respect to the housing 100 because:

- the rails 230 of the needle cover 200 are in contact with or adjacent the inner face 103 of the bottom housing peripheral wall 102, thus preventing or significantly limiting outward deflection of the arms 220 (figures 22 to 24);

- the rails 230 of the needle cover 200 are in contact with or adjacent the ribs 124 of the bottom housing 101 , for example arranged on both sides of a set 126 of ribs 124, thus preventing or significantly limiting rotation and tangential movement of the needle cover arms 220 (figure 24);

- the rails 230 of the needle cover 200 are in contact with or adjacent the ribs 164 of the top housing 150, for example arranged on both sides of a set 166 of ribs 164, thus preventing or significantly limiting rotation and tangential movement of the needle cover arms 220 (figure 21);

- the arms 220 are in contact with or adjacent the partition wall 110 that forms the inner wall of the channel 115, thus preventing or significantly limiting inward deflection of the arms 220 (figures 22 and 23);

- the arms 220 are in contact with or adjacent the side walls 112 that form the side walls of the channel 115 proximally from the second transverse wall 118, thus preventing or significantly limiting rotation and tangential movement of the needle cover arms 220 (figure 22).

In the storage position, the needle cover 200 projects beyond the housing distal end 105 so as to shield the needle 5, as shown in figures 17 and 18.

Furthermore, the autoinjector 1 comprises first biasing means for biasing the needle cover 200 distally. The first biasing means may comprise a first spring 250, for example called “safety spring”. Said first spring 250 may be a helical spring having an axis substantially coincident with the autoinjector axis A1 in the mounted position. The first spring 250 may be located inside the needle cover 200, more specifically inside the shielding portion 201 and between distal parts of the arms 220. In the illustrated embodiment, the first spring 250 bears on the bearing surface 207 of the needle cover distal end 205, at its distal part, and on the partition wall 1 10 at its proximal part.

The plunger rod 300 is mounted in the top housing 150, in the sleeve 167, with the elongated protrusion 175 of top housing 150 receiving the indentations 304 of the plunger rod 300, and with the bulge 171 of each leg 170 engaged in a corresponding hole 310 of the plunger rod 300. The plunger rod 300 is then in its initial position.

Furthermore, the autoinjector 1 comprises second biasing means for biasing the plunger rod 300 distally with respect to the top housing 150. The second biasing means may comprise a second spring 260, for example called “injection spring”. Said second spring 260 may be a helical spring having an axis substantially coincident with the autoinjector axis A1 in the mounted position. The second spring 260 may be located inside the plunger rod 300. In the illustrated embodiment, the second spring 260 bears on the collar 302 of the plunger rod 300, at its distal part, and on the transverse wall 156 of the top housing 150, at its proximal part.

The blocking member 400 is mounted in the housing 100 which is formed by the top housing 150 and bottom housing 101 assembled to one another. The sleeve 167 of the top housing 150 is received in the central bore 410 of the blocking member 400.

In the storage position, along the longitudinal direction, the blocking member 400 is located between the ribs 176 and the flange 8 of the medical container 2. The blocking member 400 may be in abutment against the ribs 176, and may be maintained in this position by the friction with the inner face 153 of the top housing peripheral wall 152 or the lip 162, or by the outward effort exerted by the legs 170 because of the force of the second spring 260.

As regards the angular position of the blocking member 400, about axis A1 , in the storage position, it is such that the pin 235 arranged on each arm 220 of the needle cover 200 is located longitudinally between the blocking member distal end 405 and the distal face 436 of the tilted rib 435 and circumferentially between the abutment wall 438 and the distal end 431 of the tilted rib 435, as shown in dotted lines in figure 29.

In this angular position, one longitudinal edge 225 of the proximal part 224 of the arm 220 may be in abutment with the longitudinal edge 403 of the corresponding cylindrical portion 402 of the blocking member body 401 that is close to the distal end 431 of the tilted rib 435. This allows preventing rotation of the blocking member 400 about axis A1 in the undesired direction. Moreover, the arm 220 preferably does not face the tab 440 - along a radial direction. For example, the opposite longitudinal edge 225 of the proximal part 224 of the arm 220 is located, circumferentially, between the abutment wall 438 and the tab 440. Moreover, in this angular position, the legs 170 of the top housing 150 abut against the substantially cylindrical inner face 413 of the central bore 410 of the blocking member 400, i.e. are circumferentially offset relative to the axial grooves 411 , as shown in figure 17.

Thus, in the storage position, the legs 170 are in their rest position and are prevented from deflecting radially outwards by the blocking member 400. Without the blocking member 400, the force exerted distally by the second spring 260 would result in the bulges 171 of the legs 170 disengaging from the holes 310 of the plunger rod 300, the plunger rod 300 thus being free to move distally. Therefore, each leg 170 form a retainer for maintaining the plunger rod 300 in its initial position against the action of the second spring 260, said retainer being held in the rest position by means of the blocking member 400. Thus, in the storage position of the needle cover 200, the blocking member 400 is in a blocking position.

Finally, the cap 500 is mounted at the autoinjector distal end. More specifically, the cap 500 is not mounted on the housing 100 but is mounted on the needle cover 200, for example owing to the protrusions 507 which cooperate with the annular flange 209. The protrusions 507 are designed to allow clipping and unclipping of the cap 500 without manual action on them, and to avoid needle cover movement during drop tests. In the storage position, the ribs 508 of the cap 500 cooperate with the distal end 105 of the housing 100 to prevent the cap 500 from proximally moving towards the bottom housing 101 . Furthermore, the bulge 521 of the legs 520 are located proximally from the proximal end of the rigid needle shield 9 of the medical container 2, as can be seen in figures 17 and 18.

The operation of the autoinjector when used is now described with reference to figures 27 to 34.

Starting from the storage position, first of all, as illustrated in figure 27, the cap 500 is removed by the user, by pulling the cap 500 distally away from the housing 100 (arrow S1). Due to the bulges 521 which engage the proximal end of the rigid needle shield 9, the cap removal automatically leads to the rigid needle shield removal.

Then, the user places the autoinjector 1 on the injection site and, while holding the housing 100, pushes the autoinjector 1 towards said injection site. As a result, the needle cover 200 is pushed (arrow S2 in figure 28). As the needle cover 200 is axially movable inside the housing 100, it moves proximally in said housing, against the force exerted by the second spring 260, until a retracted position illustrated in figure 31. In said retracted position, the needle cover 200 at least partially uncovers the needle 5 and the first spring 250 is compressed.

As shown in figure 29, when the needle cover 200 moves from the storage position to the retracted position, the pin 235 arranged on each arm 220 of the needle cover 200 first comes into contact with the distal face 436 of the corresponding tilted rib 435 of the blocking member 400. Because of the cooperation between the pin 235 and the tilted rib distal face 436, further proximal movement of the needle cover 200 causes the pin 235 to follow a path along said distal face 436 (arrow S3).

As the autoinjector 1 comprises means for guiding the axial movement of the needle cover 200 relative to the housing 100 (namely the arms 220 and rails 230 on the needle cover 200, and the channels 115 and ribs 124, 164 on the housing 100), the needle cover 200 and in particular the arms 220 are prevented from rotating relative to the housing 100. On the contrary, the blocking member 400 is rotatable about axis A1 relative to the housing 100. Therefore, the proximal movement of the needle cover 200 from its storage position to its retracted position causes the rotation of the blocking member 400 from the blocking position to a release position (arrow S4 on figure 29). The blocking member 400 may rotate by an angle comprised between 20° and 45° from its blocking position to its release position.

Following the rotation of the blocking member 400 relative to the housing 100, the autoinjector 1 is in the configuration illustrated in figures 30 and 31 .

The legs 170 of the top housing 150 are no longer radially facing the inner face 413 of the blocking member central bore 410, but are now facing the axial grooves 411. Thus, the blocking member 400 no longer forms a radial abutment for the legs 170 but on the contrary allows their outward deformation.

Due to the force of the second spring 260, the plunger rod 300 is pushed distally relative to the top housing 150. This tends to make the bulges 171 disengage from the holes 310, which was previously not possible, as this requires an outward deflection of the legs 170, which was prevented by the abutment against the inner face 413 of the blocking member central bore 410. Thus, the legs 170 deflect outwards into the axial grooves 411 (arrows S5 in figures 30 and 31). In their deformed position, shown in dotted lines in figure 31 , the legs 170 allow the plunger rod 300 to move distally relative to the housing 100.

Then, the plunger rod 300 moves distally inside the housing 100 from its initial position to an injection end position shown in figure 32. During this movement, the plunger rod 300 pushes the stopper 7 to expel the medical product out of the barrel 3 through the needle 5. In an example, if they are no longer pushed outwards by the plunger rod 300, the legs 170 have elastically returned to their rest position.

Once injection is performed, the user can remove the autoinjector 1 from the injection site. As the needle cover 200 is then not in abutment against the injection site, and because of the first spring 250 that is compressed, the needle cover 200 is moved distally relative to the housing 100 by said first spring 250, towards a safety position in which the needle cover 200 projects beyond the housing distal end so as to cover the needle 5 again. Said safety position is illustrated in figure 34. In this safety position, the distal end 242 of the tabs 240 may again abut the proximal face 125 of the ribs 124 of the bottom housing 101. Alternatively, the needle cover position relative to the housing 100 may be different in the safety position and in the storage position.

As shown in figure 33, when the needle cover 200 moves from the injection position to the safety position, the pin 235 arranged on each arm 220 of the needle cover 200 moves distally, as illustrated by arrow S6.

The autoinjector 1 is designed so that the location of the pin 235 in the injection position is aligned longitudinally with the tab 440 of the blocking member 400. Thus, the pin 235 reaches the tab 440 and moves further distally until the pin 235 is located distally from the tab 440, this movement being limited by the distal rib 439 arranged on the blocking member 400. Having a pin 235 with a tilted distal surface 237 enables facilitating the cooperation with and the inward deflection of the tab 440 during the distal movement of the needle cover 200 from the retracted position towards the safety position.

In the safety position, the needle cover 200 is prevented from moving proximally, by the cooperation between the pin 235 and the tab 440. More precisely, the pin proximal surface 236 abuts against the tab distal end 442 Preferably, the pin proximal surface 236 and/or the tab distal end 442 is substantially orthogonal to the axis A1 in order to improve the locking effect. Thus, the distal end 442 of the tab 440 forms a first stop for cooperating with the needle cover 200 in the safety position in order to prevent an axial movement of the needle cover in the proximal direction.

In addition, in the safety position, the blocking member 400 may be prevented from rotating back towards the blocking position, which could result in the needle cover 200 being free to move back to its retracted position. This is achieved by means of the abutment wall 438 arranged on the blocking member, which forms an abutment for the pin 235. Thus, the abutment wall 438 forms a second stop for cooperating with the needle cover 200 in the safety position.

The first and second stops, here the distal end 442 of the tab 440 and the abutment wall 438 are part of a locking device 450 arranged on the blocking member 400 for locking the needle cover 200 in the safety position. In an embodiment said locking device 450 is configured to cooperate with an operating portion arranged on the needle cover, which here comprises the pin 235.

The locking device ensures that the needle remains covered, therefore improving the autoinjector safety. Having the locking device arranged on the blocking member has advantages in terms of design simplicity, compactness, material savings and reliability.

Reference is now made to figures 35, 36 and 38 which show another embodiment of an autoinjector according to the invention. Only the differences with the first embodiment will be described in the following. Furthermore, as the operation of this autoinjector is identical orsimilarto the one of the previously described embodiment, it will not be described.

In this embodiment, as shown in figure 36, the top housing 150 is arranged mostly inside the bottom housing 101 , substantially only its proximal transverse wall 156 being located outside the bottom housing 101. Moreover, the snap-fitting arrangement is reversed, as the part that includes the snap-fitting protuberance 180 is the top housing 150, while the hole 140 that receives said snap-fitting protuberance 180 is provided on the bottom housing 101.

The top housing 150 may also be provided with a collar 185 configured to cooperate with hooks 485 provided on the blocking member 400. Said hooks 485 may protrude proximally from the proximal end 406 of the blocking member body 401 . This enables preventing the axial movement of the blocking member 400 both in the proximal and in the distal directions, as the collar 185 is sandwiched between the hook 485 and the transverse wall 408 at the proximal end 406 of the blocking member body 401 .

The autoinjector 1 may further comprise means for limiting the range of the rotational movement of the blocking member 400. For that purpose, the transverse wall 408 may comprise a notch 490 adjacent the recessed portion 404, said notch 490 being bounded by a first edge 491 which may be coincident with the longitudinal edge 403 adjacent the distal end 431 of the tilted rib 435, and by a second edge 492 which may be adjacent the proximal end 432 of the tilted rib 435. In addition, the top housing 150 may comprise a tongue 190 extending distally beyond the blocking member transverse wall 408, in the mounted position. Thus, the tongue 190 can abut the first edge 491 orthe second edge 492 of the notch 490, thereby limiting the rotational movement of the blocking member 400 about axis A1 relative to the housing 100.

Reference is now made to figures 39 and 40 which illustrate an embodiment in which the initiating moment of the retainer release and the triggering period of the actual injection are controlled.

Thus, the autoinjector 1 may be configured to set the beginning of the injection with respect to the pricking depth, so as to ensure that all the medical product will be expelled from the medical container and injected into the injection site. More specifically, the axial grooves 411 may be configured to allow the deformation of the retainer 170 to start when the needle cover 200 has moved axially along a predetermined length and, preferably, to control the deformation speed of the retainer 170 towards its deformed position.

The longitudinal edge between the inner face 413 of the blocking member body 401 and the axial groove 411 that is the last contact portion between the retainer 170 and the inner face 413 before the retainer 170 is allowed to deform following the rotation of the blocking member 400 is called activation edge 414. The axial groove 411 comprises a control face 415 which extends from the activation edge 414 towards the inner space of said axial groove 411 and away from the housing axis A100. As shown in figure 40, the control face 415 is inclined relative to a radial segment 195 of the housing 100 passing through the activation edge 414 by an angle a. Angle a can be comprised between 25° and 50°, preferably between 35° and 45°. This ensures a quick start of the injection but a smooth transition from the initial position of the plunger rod and its injection end position.

The invention is not limited to the embodiments described above by way of examples but it rather comprises all the technical equivalents and variants of the means described as well as their combinations.

It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.

Claims

1. An autoinjector (1) for automatic injection of a product into an injection site, said autoinjector (1) comprising: a housing (100) having an axis (A100) which defines a longitudinal direction, the housing (100) being configured to receive a medical container (2) comprising a barrel (3) defining a reservoir for containing a medical product, said barrel (3) having a distal end (4) provided with a needle (5) and an open proximal end (6) configured to receive a plunger rod (300) for pushing a stopper (7) arranged inside the barrel (3); an inner sleeve (167) arranged axially inside the housing (100) and secured to the housing (100); a needle cover (200) coupled to said housing (100), the needle cover (200) being rotationally fixed relative to the housing (100) and axially movable inside said housing (100) between a storage position in which the needle cover (200) projects beyond the housing distal end (105) so as to shield the needle (5); a retracted position in which the needle cover (200) has moved proximally with respect to the housing (100) from the storage position so as to at least partially uncover the needle (5); and a safety position in which the needle cover (200) has moved back distally with respect to the housing (100) from the retracted position and projects beyond the housing distal end (105) so as to shield the needle (5); guide means (103, 115, 124, 164) fixedly arranged on the housing (100) in order to guide the axial movement of the needle cover (200) relative to the housing (100); first biasing means (250) for biasing the needle cover (200) distally; a plunger rod (300) axially movable inside the housing (100) between an initial position and an injection end position distally located relative to said initial position, the plunger rod (300) being configured to push the stopper (7) to expel the medical product; second biasing means (260) for biasing the plunger rod (300) distally; a retainer (170) for maintaining the plunger rod (300) in the initial position against the action of the second biasing means (260), the retainer (170) being arranged at the distal portion of the inner sleeve (167), the retainer (170) being elastically deformable between a rest position in which the retainer (170) axially abuts against the plunger rod (300) for blocking the plunger rod (300) in said initial position, and a deformed position in which the retainer (170) is radially deflected to allow the plunger rod (300) to move distally; a blocking member (400) arranged inside the housing (100), said blocking member (400) being axially fixed relative to the housing (100) and rotatable relative to the housing (100) about the axis (A100) between a blocking position, in which the blocking member (400) prevents the deformation of the retainer (170) and therefore holds the retainer (170) in the rest position, and a release position, in which the blocking member (400) allows the deformation of the retainer (170), the rotation of the blocking member (400) from the blocking position to the release position being caused by the needle cover (200) moving from the storage position to the retracted position, the blocking member (400) including a locking device (450) configured to lock the needle cover (200) in the safety position.

2. The autoinjector according to claim 1 , wherein the locking device (450) comprises a first stop (442), which preferably extends substantially orthogonally to the axis (A100), for cooperating with the needle cover (200) in the safety position in order to prevent an axial movement of the needle cover (200) in the proximal direction.

3. The autoinjector according to claim 2, wherein the blocking member (400) comprises a body (401) and the locking device (450) comprises a tab (440) which has a base (441) secured to the body (401) and a free distal end (442), the tab (440) protruding obliquely from the body (401), in the distal direction and towards the needle cover (200), the tab (440) being elastically deflectable towards the body (401) by the needle cover (200) moving from the retracted position to the safety position, the distal end (442) of the tab (440) forming said first stop.

4. The autoinjector according to any one of claims 1 to 3, wherein the locking device (450) comprises a second stop (438), which preferably extends in a plane substantially parallel to the axis (A100), for cooperating with the needle cover (200) in the safety position in order to prevent a rotation of the blocking member (400) back towards the blocking position.

5. The autoinjector according to claim 4, wherein the second stop (438) comprises a wall extending substantially axially and protruding towards the needle cover (200).

6. The autoinjector according to any one of claims 1 to 5, wherein the blocking member (400) comprises a cam surface (436) which projects towards the needle cover (200) and which is tilted relative to the axis (A100), said cam surface (436) being configured to cooperate with the needle cover (200) so that the movement of the needle cover (200) from the storage position to the retracted position causes the rotation of the blocking member (400) from the blocking position to the release position.

7. The autoinjector according to any one or several of claims 2 to 6, wherein the needle cover (200) comprises an operating portion (235) for cooperating with the first stop (442), and/or the second stop (438), and/or the cam surface (436), said operating portion (235) comprising at least one pin protruding towards the blocking member (400).

8. The autoinjector according to any one of claims 1 to 7, wherein the needle cover (200) comprises guide means (220, 230) configured to cooperate with the guide means (103, 115, 124, 164) fixedly arranged on the housing (100), whereby the axial movement of the needle cover (200) relative to the housing (100) is guided and, preferably, the radial or tangential movement of the needle cover (200) relative to the housing (100) is limited.

9. The autoinjector according to any one of claims 1 to 8, wherein the needle cover (200) has a distal portion comprising a shielding portion (201), said shielding portion (201) being substantially cylindrical, and at least one arm (220) that extends proximally from the shielding portion (201).

10. The autoinjector according to claim 9, wherein the housing (100) comprises a channel (1 15) that extends axially and receives the needle cover arm (220), at least part of the side ends of the arm (220) being located in abutment with an inner surface (116) of the channel (115).

11. The autoinjector according to claim 9 or 10, wherein the needle cover arm (220) has a main wall (221) and comprises at least one rail (230) that extends axially and protrudes outwards from said main wall (221), said rail (230) being configured to be in abutment with an inner peripheral wall (103) of the housing (100).

12. The autoinjector according to claim 11 , wherein the needle cover arm (220) comprises a tab (240) which has a base (241) secured to the arm main wall (221) and a free distal end (242), the tab (240) protruding obliquely from the main wall (221), in the distal direction and towards the housing (100), the tab (240) being elastically deflectable towards the axis (A100) to allow mounting the needle cover (200) in the housing (100), and wherein, in the storage position and the safety position, the distal end (242) of the tab (240) is configured to be in abutment with at least one rib (124) that protrudes inwards from the housing (100) and extends axially, in order to prevent the needle cover (200) from moving distally with respect to the housing (100).

13. The autoinjector according to any one of claims 9 to 12, wherein the needle cover arm (220) has a main wall (221) and comprises at least one rail (230) that extends axially and protrudes outwards from said main wall (221), said rail (230) being configured to be in abutment with at least one rib (124, 164) that protrudes inwards from the housing (100) and extends axially.

14. The autoinjector according to any one of claims 9 to 13, wherein, in the storage position, part of the side ends (225) of the arm (220) are in abutment with a face (403) of the blocking member (400) that extends in a plane substantially parallel to the axis (A100).

15. The autoinjector according to any one of claims 1 to 14, wherein the blocking member (400) comprises a body (401) which includes: a central bore (410) in which the inner sleeve (167) is received, the central bore (410) having an inner face (413); at least one axial groove (411) which opens in said central bore (410); wherein, in the blocking position, the blocking member (400) is positioned such that the retainer (170) radially faces the inner face (413) of the central bore (410) and, in the release position, the blocking member (400) is positioned such that the retainer (170) radially faces the axial groove (411); wherein the axial groove (411) is configured to allow the deformation of the retainer (170) to start when the needle cover (200) has moved axially along a predetermined length and, preferably, to control the deformation speed of the retainer (170) towards its deformed position.

16. The autoinjector according to any one of claims 1 to 15, wherein the blocking member (400) comprises a body (401) which includes: a central bore (410) in which the inner sleeve (167) is received, the central bore (410) having an inner face (413); at least one axial groove (411) which opens in said central bore (410); wherein, in the blocking position, the blocking member (400) is positioned such that the retainer (170) radially faces the inner face (413) of the central bore (410) and, in the release position, the blocking member (400) is positioned such that the retainer (170) radially faces the axial groove (411); wherein a longitudinal edge between the inner face (413) and the axial groove (411) is the last contact portion between the retainer (170) and the inner face (413) before the retainer (170) is allowed to deform following the rotation of the blocking member (400), said longitudinal edge being called activation edge (414); wherein the axial groove (411) comprises a control face (415) which extends from the activation edge (414) towards the inner space of said axial groove (411) and away from the housing axis (A100), said control face (415) being inclined relative to a radial segment (195) of the housing passing through the activation edge by an angle (a) comprised between 25° and 50°, preferably between 35° and 45°.

17. A medical device comprising an autoinjector (1) according to any one of the preceding claims and a medical container (2) comprising a barrel (3) defining a reservoir for containing a medical product, said barrel (3) having a distal end (4) provided with a needle (5) and an open proximal end (6) configured to receive a plunger rod (300) for pushing a stopper (7) arranged inside the barrel (3), said medical container (2) being received in the housing (100) of the autoinjector (1).