Re-usable safety device, injection device including this re-usable safety device and method for resetting the re-usable safety device

Abstract

This safety device (1) includes: a bottom housing (4), extending along a longitudinal axis A and configured for accommodating a medical container (2) provided with an injection needle (21); a top housing (5) configured to be connected to the bottom housing (4) in order to axially block the medical container (2) inside the bottom housing (4); a needle cover (3), movable with respect to the bottom housing (4) between an initial position, a retracted position, proximally located with respect to the initial position, and a safety position, distally located with respect to the retracted position, in which a proximal abutment surface (356) of the needle cover (3) abuts against a blocking member (43) of the bottom housing (4) such that the needle cover (3) cannot move back in the proximal direction; and resetting means (338b, 351) configured for allowing disengagement of the proximal abutment surface (356) and the blocking member (43) such that the needle cover (3) can move from the safety position to the initial position.

Description

[0001] Re-usable safety device, injection device including this re-usable safety device and method for resetting the re-usable safety device

[0002] The present invention relates to a reusable safety device and to an injection device including the reusable safety device. The invention also relates to a method for assembling the reusable safety device to the injection device.

[0003] 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 “distal direction” is to be understood as meaning the direction away from the user's hand, and the “proximal direction” is to be understood as meaning the direction toward the user's hand.

[0004] Some injection devices include a syringe provided with an injection needle, and a safety device mounted around the syringe, the safety device including a needle cover that extends in a safety position after injection to protect a user against needle stick injuries. Usually, after injection, the syringe is discarded in a sharps container together with the safety device locked in the safety position. A new syringe equipped with another safety device is required to perform another injection operation. That is, a new safety device needs to be used for every injection operation.

[0005] It is known from the document AU2012342450 an autoinjector comprising a case, a drive carriage disposed in the case, and a plunger coupled to the drive carriage. It is known from the document US2023158252 a method for assembling a cassette for use in an autoinjector. Document GB2506918 discloses an autoinjector comprising heating means for heating the contents of a syringe prior to injection. Document US2013245561 discloses a medical device for delivering at least two drug agents from separate reservoirs using auto-injection devices comprising a dose setting mechanism and a single dispense interface.

[0006] There is therefore a need for a safety device that provides an improved sustainability.

[0007] An aspect of the invention is a safety device configured for preventing needle sticks, the safety device including: a bottom housing, extending along a longitudinal axis A and configured for accommodating a medical container provided with an injection needle; a top housing configured to be connected to the bottom housing in order to axially block the medical container inside the bottom housing, a needle cover, movable with respect to the bottom housing between an initial position, a retracted position, proximally located with respect to the initial position, and a safety position, distally located with respect to the retracted position, in which a proximal abutment surface of the needle cover abuts against a blocking member of the bottom housing such that the needle cover cannot move back in the proximal direction, resetting means configured for allowing disengagement of the proximal abutment surface and the blocking member such that the needle cover can move from the safety position to the initial position.

[0008] The safety device of the invention can thus be-reused. The safety device of the invention accordingly improves sustainability, because only the used medical container is discarded. Once reset, the safety device of the invention can receive a new (not yet used) medical container to allow the user to safely perform another injection operation.

[0009] The safety device may include fasteners for allowing removable attachment of the bottom housing to the top housing so that the bottom housing and the top housing can be detached to allow for removal of the medical container after injection.

[0010] The resetting means may include a guiding pin engaged within a guiding track to guide axial and rotational movement of the needle cover from the initial position to the safety position, the resetting means being configured for allowing disengagement of the proximal abutment surface and the blocking member and movement of the guiding pin back from the safety position to the initial position after removal of the medical container.

[0011] In an embodiment, the top housing includes a temporary blocking member which is radially movable between a blocking position, in which the temporary blocking member distally abuts against the bottom housing such that the top housing cannot distally move with respect to the bottom housing, and a release position, in which the temporary blocking member no longer axially abuts against the bottom housing so that the top housing can move in the distal direction with respect to the bottom housing.

[0012] In an embodiment, the needle cover includes an injection-triggering member configured for abutting against the temporary blocking member of the top housing such that the temporary blocking member moves to the release position.

[0013] In an embodiment, the plunger rod is fixed to the top housing.

[0014] In an embodiment, the top housing includes an axially movable distal abutment surface configured for axially abutting against a flange of the medical container, and biasing means configured for pressing the distal abutment surface of the top housing against the flange of the medical container.

[0015] In an embodiment, the bottom housing includes a proximal abutment surface configured for axially abutting against a flange of the medical container, and a distal abutment surface configured for axially abutting against an injection-depth defining member of the needle cover.

[0016] This permits to control the injection depth with a high accuracy.

[0017] In an embodiment, the top housing is removably attached to the bottom housing.

[0018] In an embodiment, the bottom housing includes a resiliently deformable fastener for attaching the bottom housing to the top housing, and the resiliently deformable fastener includes an outer pressing portion allowing a user to radially inwardly deform the resiliently deformable fastener from a blocking position, in which the resiliently deformable fastener prevents removal of the top housing from the bottom housing, to a release position, in which the top housing can be removed from the bottom housing.

[0019] In an embodiment, the resetting means include a resetting portion of a guiding track engaged by a guiding pin, the resetting portion being configured for guiding movement of the needle cover from the safety position to the initial position by rotation of the needle cover with respect to the bottom housing around the longitudinal axis A without need for the needle cover to move back in the proximal direction with respect to the bottom housing.

[0020] In an embodiment, the resetting means include a resilient leg and the resilient leg includes the proximal abutment surface of the needle cover, the resilient leg being radially deformable between a blocking position, in which the proximal abutment surface abuts against the blocking member of the bottom housing, and a release position, radially inwardly located with respect to the blocking position, in which the proximal abutment surface is shifted away from the blocking member, such that the needle cover can move back in the proximal direction from the safety position to the retracted position.

[0021] The resilient leg is configured to be kept in the blocking position by the medical container contained within the bottom housing. Movement of the resilient leg from the blocking position to the release position is caused by removal of the medical container from the bottom housing.

[0022] In an embodiment, the safety device includes a cap removably attached to a distal end of the needle cover, the cap including a remover configured for removing a needle shield of the medical container.

[0023] Another aspect of the invention is an injection device including the abovedescribed safety device and a medical container arranged within the housing of this safety device Another aspect of the invention is a method for re-setting the above-described safety device, the method comprising the steps of: removing a medical container from the bottom housing; moving the needle cover from the safety position to the initial position.

[0024] Preferably, the removed medical container is a used medical container. The step of removing a medical container from the bottom housing may first include removal of the top housing from the bottom housing.

[0025] The return of the needle cover to the initial position may be done by a rotation, without need for the needle cover to first go back to the retracted position. Alternatively, the return of the needle cover to the initial position may be done by first moving the needle cover back in the proximal direction from the safety position to the retracted position and then by moving the needle cover in the distal direction from the retracted position to the initial position.

[0026] In an embodiment, the step of removing the used medical container from the bottom housing is necessary to carry out the step of moving the needle cover from the safety position to the initial position. In another embodiment, the step of removing the medical container from the bottom housing may be carried out after moving the needle cover from the safety position to the initial position.

[0027] Optionally, the method may comprise a first step of putting the needle shield back onto the medical container.

[0028] The method may further include a step of inserting a new medical container within the housing. Eventually, the method may comprise attaching the top housing back to the bottom housing.

[0029] The invention and the advantages arising therefrom will clearly emerge from the detailed description that is given below with reference to the appended drawings as follows :

[0030] Figure 1 is an exploded view of a safety device according to an embodiment of the invention,

[0031] Figure 2 is an exploded view of an injection device according to an embodiment of the invention,

[0032] Figure 3 is a perspective view of an injection device according to an embodiment of the invention,

[0033] Figure 4 is a cross-section view of an injection device according to an embodiment of the invention, the needle cover and the top housing being in the initial position,

[0034] Figure 5 is a perspective view of the injection device of Figure 4, illustating the needle cover in the initial position,

[0035] Figure 6 is a cross-section view in a plane orthogonal to the cutaway of Figure 4, illustrating a fastener of the bottom body in a blocking position,

[0036] Figure 7 is a detail of Figure 4, illustrating a washer of the top housing, Figure 8 is a perspective view of an injection device according to an embodiment of the invention just before injection, the needle cover being in the retracted position and the top housing being in the initial position,

[0037] Figure 9 is a perspective view of a temporary blocking member of the top housing of an injection device according to an embodiment of the invention, Figure 10 is a cross-section view of an injection device according to an embodiment of the invention, just before injection, the needle cover being close to reaching the retracted position and the top housing being in the initial position,

[0038] Figure 11 is a perspective view of the injection device of Figure 8, illustrating the needle cover in the retracted position, the bottom housing being semitransparent,

[0039] Figure 12 is a perspective view of an injection device according to an embodiment of the invention at the end of injection, the top housing being in the injection position,

[0040] Figure 13 is a cross-section view of an injection device according to an embodiment of the invention at the end of injection,

[0041] Figure 14 is a cross-section view of an injection device according to an embodiment of the invention, just before injection, the needle cover being close to reaching the retracted position and the top housing being in the initial position,

[0042] Figure 15 is a perspective view of an injection device according to an embodiment of the invention, the needle cover being in the safety position, Figure 16 is a cross-section of an injection device according to an embodiment of the invention, the needle cover being in the safety position,

[0043] Figure 17 is a perspective view of the injection device of Figure 15, illustrating the needle cover in the safety position, the bottom housing being semitransparent,

[0044] Figure 18 is a cross-section view of an injection device according to an embodiment of the invention, the fastener of the bottom housing and the fastener of the top housing being engaged with each other,

[0045] Figure 19 is a perspective view of an injection device according to an embodiment of the invention, the needle cover being moved back to the initial position in order to reset the safety device,

[0046] Figure 20A is a perspective view of a needle cover of an injection device according to an embodiment of the invention, Figure 20B is a detail of Figure 20A,

[0047] Figures 21-22 are perspective views of a bottom housing of an injection device according to an embodiment of the invention,

[0048] Figures 23-24 are perspective views of a ring of an injection device according to an embodiment of the invention,

[0049] Figures 25-26 are perspective views of a top housing of an injection device according to an embodiment of the invention,

[0050] Figures 27-28 are perspective views of a washer of an injection device according to an embodiment of the invention,

[0051] Figure 29 is a perspective view of a needle cover of an injection device according to an embodiment of the invention,

[0052] Figure 30 is a perspective view of a needle cover of an injection device according to an embodiment of the invention,

[0053] Figures 31-32 are, respectively, a perspective and a cross-section view of a cap of an injection device according to an embodiment of the invention, Figures 33-34 are perspective views of a top housing of an injection device according to an embodiment of the invention.

[0054] The different features of the embodiments can be used in combination with and used with other embodiments as long as the combined parts are not inconsistent with or interfere with the operation of the device and assembly. The phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," or "having" and variations thereof herein is to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms "connected," "coupled," and "mounted," and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms "connected" and "coupled" and variations thereof are not limited to physical or mechanical connections or couplings. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be understood that, although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element without departing from the scope of the present disclosure. With reference to Figures 1 and 2 are shown a safety device 1 and an injection device 10 according to an embodiment of the invention. The injection device 10 is configured for allowing injection of a medical product into an injection site. The injection device 10 may be a manual auto-injector, i.e. can be grasped in the user’s hand but the injection is manual (the medical product is expelled due to the force exerted by the user on said injection device 10). The injection device 10 extends along a longitudinal axis A and includes a medical container 2 configured for containing a medical product, and a re-usable safety device 1 for preventing needle stick injuries.

[0055] The medical container 2 may be a prefillable or prefilled syringe. The medical container 2 includes a tubular barrel 20 defining a reservoir for containing the medical product to be injected. The barrel 20, which may be made of a glass material, has a distal end provided with an injection needle 21 , and a needle shield 22 removably attached to the distal end of the barrel

[0056] 20 for protecting and sealing the injection needle 21 before use. The barrel 20 has an opened proximal end which may be provided with a radial flange 23. The proximal end of the barrel 20 defines a proximal opening configured to receive a plunger rod 53 of a top housing 5 as will be described below. A stopper 25 arranged within the barrel 20 is configured to move towards the distal end of the barrel 20 under the distal pressure of the plunger rod 53 in order to expel the medical product via the injection needle 21 .

[0057] As will be explained in further details below, the medical container 2 may be removably mounted within the re-usable safety device 1 .

[0058] The re-usable safety device 1 is configured for protecting users against needle stick injuries. In the present invention, the re-usable safety device 1 is further configured for allowing, after injection, removal of the used medical container 2 such that the used medical container 2 can be discarded and for allowing subsequent assembly of the re-usable safety device 1 to a new, not yet used, medical container 2 such that the re-usable safety device 1 can again protect users against needle stick injuries during and after use of this new medical container 2. The re-usable safety device 1 of the invention includes a needle cover 3 for covering the injection needle 21 , a bottom housing 4 for accommodating the medical container 2, and a top housing 5 for keeping the medical container 2 inside the bottom housing 4 and for pushing the stopper 25 inside the barrel 20 during injection. As illustrated in Figure 2, the re-usable safety device 1 is an add-on safety device 1 , i.e. can be removably mounted onto any medical container 2.

[0059] With reference to Figures 20A-20B is shown a needle cover 3 according to an embodiment of the invention. The needle cover 3 is configured for covering the injection needle

[0060] 21 in order to prevent needle stick injuries. The needle cover 3 may be made of a single piece. The needle cover 3 is axially and rotationally movable with respect to the bottom housing 4. The axial movement of the needle cover 3 extends between an initial position (Figures 3, 4), a (fully) retracted position (Figures 8, 12) proximally located with respect to the initial position, and a safety position (Figures 15, 16) distally located with respect to the retracted position. The safety position and the initial position may be similar or different; if different, the safety position may be distally located with respect to the initial position. In the initial position, the needle cover 3 protects the needle shield 22. In the retracted position, the needle cover 3 unveils the injection needle 21 so that the injection needle 21 can penetrate into the injection site. In the safety position, the needle cover 3 covers the injection needle 21 to protect the user against needle sticks. The needle cover 3 may further move to a partially retracted position (not shown), axially located between the initial position and the retracted position, to allow for withdrawal of the needle shield 22. Axial movement of the needle cover 3 in the distal direction is caused by biasing means such as a safety spring 7. Axial movement of the needle cover 3 in the proximal direction is caused by the user pressing a distal end of the needle cover 3 against an injection site.

[0061] The rotational movement of the needle cover 3 extends between an armed rotational position (before injection), Figures 3-4, in which the needle cover 3 is ready to be used, and an activated rotational position (after injection), Figures 15-16, in which the safety mechanism of the needle cover 3 is activated such that the needle cover 3 prevents from needle sticks and thus forbids re-use of the medical container 2 to perform another injection operation. Rotation of the needle cover 3 from the armed rotational position to the activated rotational position is caused by the user pressing the distal end of the needle cover 3 against the injection site. Rotation of the needle cover 3 from the activated rotational position back to the armed rotational position is caused by the user re-arming the needle cover 3 after injection and disposal of the used medical container 2 in order to re-use the safety device 1 with a new medical container 2.

[0062] With reference to Figures 20A-20B, the needle cover 3 may be in the form of an elongated tubular sleeve which extends along the longitudinal axis A. The needle cover 3 has a cylindrical lateral wall 30 defining an inner cavity, a distal end 31 defining a distal opening 31 1 for allowing passage of the injection needle 21 and of the needle shield 22, and a proximal end 32 defining a proximal opening 321 for allowing extension of the barrel 20 inside the inner cavity. The lateral wall 30 may have inspection windows 301 so that the user can visually inspect the barrel 20 and its contents. The distal end 31 of the needle cover 3 may define a circumferential ring 312 forbidding access to the inner cavity for the user’s fingers. The distal end 31 further delimits a distal pushing surface 313 configured for pressing against the injection site to cause retraction of the needle cover 3. The needle cover 3 may further include a proximal supporting surface 322, which may be arranged at the proximal end of the needle cover 3 for providing support for a safety spring 7. The needle cover 3 also includes a guiding member 33, a locker 35, and an injection-triggering member 39, which are described in more details below.

[0063] As illustrated in Figures 20A-20B, the guiding member 33 may be in the form of a guiding track which may be arranged at an outer surface of the lateral wall 30 of the needle cover 3 for guiding the axial and rotational movements of the needle cover 3 with respect to the housing 4. To that end, the guiding member 33 is configured for engaging a complementary guiding member, such as a guiding pin 41 , of the housing 4. The guiding member 33 may include a first delimiting rib 330a and a second delimiting rib 330b that delimit a first portion 332a, a second portion 332b, a connecting portion 338a that connects the first and second portions 332a, 332b, and a resetting portion 338b. The second delimiting rib 330b is arranged inside the first delimiting rib 330a to help guide the guiding pin 41 along the guiding track 33. The delimiting ribs 330a, 330b are closed. The first portion 332a may include an initial distal stop 333 and a proximal stop 334 separated from each other by a predetermined axial distance. An injection-depth defining member 339 may be arranged at the junction of the connecting portion 338a and the second portion 332b for controlling the injection depth. The second portion 332b includes a final distal stop 337.

[0064] The first portion 332a may be straight from the proximal end 335 to its distal end, and may also be slightly inclined with respect to the longitudinal axis A to cause a slight rotation of the needle cover 3 towards the activated rotational position. The initial distal stop 333 of the first portion 332a may be arranged at the proximal end 335 of the first portion 332a or between the opened proximal end 335 of the first portion 332a and the distal end of the first portion 332a in order to maintain the needle cover 3 in the initial position. The initial distal stop 333 is configured for axially abutting against the guiding pin 41 of the housing 4 when the needle cover 3 is in the initial position so that the needle cover 3 cannot move distally from said initial position. The proximal stop 334 of the first portion 332a may be arranged at the distal end of the first portion 332a to oppose a proximal movement of the needle cover 3 as long as the proximal force exerted on the needle cover 3 is below a predetermined threshold. This permits the user to partially retract the needle cover 3 in the partially retracted position, in which the proximal stop 334 axially abuts against the guiding pin 41 of the housing 4, such that the user may grasp and remove the needle shield 22 before an injection operation. The first portion 332a is however configured to allow passage of the guiding pin 41 over the proximal stop 334 during use of the injection device 10, i.e. when the user presses the distal end 31 of the needle cover 3 against the injection site. Therefore, the proximal stop 334 may be inclined and / or may be radially smaller than the initial distal stop 333. The connecting portion 338a connects the distal end of the first portion 332a to the distal end of the second portion 332b, and therefore allows passage of the guiding pin 41 from the first portion 332a to the second portion 332b. The connecting portion 338a may further be configured for causing and / or completing rotation of the needle cover 3 from the armed rotational position to the activated rotational position. The connecting portion 338a is accordingly inclined with respect to the longitudinal axis A. The connecting portion 338a may have a rounded shape or may be straight. The injection-depth defining member 339 is arranged at the distal end of the second portion 332b and defines a proximal abutment surface for axially blocking the needle cover 3. In the retracted position, the injection-depth defining member 339 thus axially abuts against the guiding pin 41 of the bottom housing 4 so that the needle cover 3 cannot move further in the proximal direction. Since the injection depth is defined as the axial distance between a distal end of the injection needle 21 and the distal end 31 of the needle cover 3, the blocking of the needle cover 3 in the retracted position by the pricking-depth defining member 339 permits to control the injection depth.

[0065] The second portion 332b may be straight and may be parallel to the longitudinal axis A. The final distal stop 337 is arranged at a proximal end of the second portion 332b to distally block the needle cover 3. In the safety position, the final distal stop 337 thus axially abuts against the guiding pin 41 of the housing 4 so that the needle cover 3 cannot move further in the distal direction. When the guiding pin 41 of the housing 4 is in the second portion 332b of the guiding track 33, rotation of the needle cover 3 is completed: the needle cover 3 is in the activated rotational position, which allows the locker 35 of the needle cover 3 to engage with the blocking member 43 of the bottom housing 4 as will be explained below.

[0066] The resetting portion 338b is a second connecting portion 338b that connects the first and second portions 332a, 332b. The resetting portion 338b may form resetting means for allowing reset, and thus re-use, of the safety device 1. It is contemplated that the first connecting portion 338a connects the distal ends of the first and second portions 332a, 332b, whereas the resetting portion 338b connects the proximal ends of the first and second portions 332a, 332b. As a result, the guiding track 33 forms some sort of closed loop configured to be traveled by the guiding pin 41 of the bottom housing 4 each time the safety device 1 is being used. The second connecting portion 338b allows for moving the guiding pin 41 of the bottom housing 4 from the second portion 332b to the first portion 332a of the guiding track 33 by a mere rotation of the needle cover 3 around the longitudinal axis A. Therefore, the re-setting of the needle cover 3 may be fast. The second connecting portion 338b may be straight, and may extend orthogonal to the longitudinal axis A. As illustrated in Figure 20B, on one side, the second connecting portion 338b may be at the same axial position as the final distal stop 337 so that the guiding pin 41 can leave the safety position by a simple rotation, without requiring any axial movement of the guiding pin 41 with respect to the needle cover 3. On the other side, the second connecting portion 338b opens into the first portion 332a at a location axially comprised between the initial distal stop 333 and the proximal stop 334 of the first portion 332a, preferably closer to the initial distal stop 333 than to the proximal stop. An anti-return shoulder 336b, defining an orthoradial abutment surface, may separate the initial distal stop 333 from the second connecting portion 338b to prevent the guiding pin 41 from directly moving from the initial position to the safety position by a simple rotation of the needle cover 3 around the longitudinal axis A. That is, in the initial position, the anti-return shoulder 336b prevents any rotation of the needle cover 3 so that the only possible movement of the guiding pin 41 is an axial movement along the first portion 332a in the distal direction with respect to the needle cover 3.

[0067] Still with reference to Figure 20B, the needle cover may include a mounting rib 330c arranged next to the guiding track 33 for easing insertion of the guiding pin 41 of the bottom housing 4 in the guiding track 33. The mounting rib 330c may protrude from an outer surface of the lateral wall 30 of the needle cover 3, and may be straight and oblique with respect to the longitudinal axis A. The mounting rib 330c is located proximal to the first portion 332a of the guiding track 33. The mounting rib 330c has one proximal end and an opposite distal end which is connected to the delimiting rib 330a. The mounting rib 330c and the delimiting rib 330a may thus form a V-shaped notch for guiding the guiding pin 41 towards and into the guiding track 33. This portion of the delimiting rib 330a, which may also delimit the connecting portion 338a, may have a sloped distal side to ease passage of the guiding pin 41 over the delimiting rib 330a during assembly of the needle cover 3 to the bottom housing 4.

[0068] Still with reference to Figures 20A-20B, the locker 35 is configured for proximally blocking the needle cover 3 when the needle cover 3 is in the safety position. The locker 35 is also configured for allowing disposal of the used medical container 2 and for allowing re-use of the safety device 1 . More specifically, the locker 35 is configured for allowing movement of the needle cover 3 back to the initial position after disposal of the used medical container 2. The locker 35 thus engages the bottom housing 4 when the needle cover 3 is in the safety position and can disengage the bottom housing 4 to re-use the safety device 1 , preferably after disposal of the used medical container 2.

[0069] In the activated rotational position, the locker 35 of the needle cover 3 and the blocking member 43 of the bottom housing 4 are axially aligned. In the armed rotational position, the locker 35 of the needle cover 3 and the blocking member 43 of the bottom housing 4 are not aligned; they are offset from each other. Therefore, in the armed rotational position, the locker 35 and the blocking member 43 cannot interfere with each other.

[0070] As illustrated in Figure 20A, the locker 35 is in the form of a protrusion that outwardly radially protrudes from the lateral wall 30 of the needle cover 3. Thus, the locker 35 is here fixed with respect to the rest of the needle cover 3. The locker 35 however still rotate together with the needle cover 3 with respect to the bottom housing 4. In the activated rotational position, the locker 35 of the needle cover 3 and the blocking member 43 of the bottom housing 4 are axially aligned. In the armed rotational position, the locker 35 of the needle cover 3 and the blocking member 43 of the bottom housing 4 are not aligned; they are offset from each other. This allows for assembly of the bottom housing 4 and the needle cover 3. The locker 35 may here longitudinally extend orthogonal to the longitudinal axis A. The distal side of the locker 35 forms a ramp configured to ease passage of the blocking member 43 of the bottom housing 4 over the locker 35 when the needle cover 3 moves from the retracted position to the safety position. A proximal side of the locker 35 defines the proximal abutment surface 356 configured for axially abutting against the bottom housing 4 when the needle cover 3 is in the safety position. Therefore, the locker 35 prevents proximal movement of the needle cover 3 when the needle cover 3 is in the safety position. This protects the user against needle sticks. An opposite distal side of the locker 35 may form a ramp for easing outward deformation of the blocking member 43 of the bottom housing 4. The needle cover 3 may include one or more, for instance two diametrically opposite, guiding members 33 and one or more, for instance two diametrically opposite lockers 35.

[0071] The injection-triggering member 39 may be in the form of an axially extending leg that proximally extends from the proximal end 32 of the needle cover 3. The injection-triggering member 39 may extend in a straight direction so that it is parallel to the longitudinal axis A. The injection-triggering member 39 may extend proximally beyond the proximal end 32 of the needle cover 3. Besides, the injection-triggering member 39 is outwardly radially located relative to the lateral wall 30 of the needle cover. The injection-triggering member 39 is fixed with respect to the needle cover 3; they may be made of a single piece.

[0072] The injection-triggering member 39 includes a distal end 390 which may be fixed to the outer surface of the lateral wall 30 of the needle cover 3 and an opposite free proximal end 391 . The injection-triggering member 39 further has a proximal abutment element 392 configured for abutting against a temporary blocking member 55 of the top housing 5 when the needle cover 3 reaches the retracted position, in order to allow for outward deformation of the temporary blocking member 55 such that injection can begin, as will be explained in details below. The proximal abutment element 392 may be defined at the proximal end 391 of the axially extending leg 39. The needle cover 3 may include one or two diametrically opposite injection-triggering members 39.

[0073] With reference to Figures 21-22, the bottom housing 4 is configured for receiving the medical container 2 and for guiding movements of the needle cover 3. The bottom housing 4 is further configured for accommodating biasing means in the form of the safety spring 7 for pushing the needle cover 3 in the distal direction.

[0074] The bottom housing 4 may be in the form of a tubular sleeve extending along the longitudinal axis A and which surrounds the proximal end 32 of the needle cover 3. The bottom housing 4 may be removably attached to the top housing 5. The bottom housing 4 includes a cylindrical lateral wall 40, a distal end 401 and a proximal end 403. The lateral wall 40 defines an inner cavity leading, on one hand, to a distal opening 402 delimited by the distal end 401 of the bottom housing 4 and, on the other hand, to a proximal opening 404 delimited by the proximal end 403 of the bottom housing 4. As shown in Figure 21 , a distal portion 46 of the bottom housing 4 may have a smaller diameter than the rest of the bottom housing 4, and may be connected to the rest of the bottom housing 4 by a tapered portion 47. The rest of the bottom housing 4 thus provides room for the injection-triggering member 39 of the needle cover 3.

[0075] The bottom housing 4 may further include some or all of a guiding member 41 , a proximal abutment surface 42, Figures 23-24, a distal abutment surface 414, a blocking member 43, a proximal stop 44, and fasteners 45. There may be one or more, for instance two diametrically opposite, guiding members 41 , one or more, for instance two diametrically opposite blocking members 43, one or more, for instance two diametrically opposite proximal stops 44 and one or more, for instance two diametrically opposite fasteners 45.

[0076] The guiding member, such as a guiding pin 41 , is configured for engaging the guiding track 33 of the needle cover 3 and therefore guide axial and rotational movements of the needle cover 3 from the initial position to the safety position and vice versa. The guiding member 41 may be in the form of an axially extending leg arranged within a window 411 provided through the lateral wall 40 of the bottom housing 4, and includes a distal end 412 which may be free and an opposite proximal end 413 which may be fixedly connected to the lateral wall 40 of the bottom housing 4. The guiding member 41 is arranged near the distal end 401 of the bottom housing 4.

[0077] The guiding member 41 is resiliently deformable in the radial direction such that the guiding member 41 can enter into the guiding track 33 when the bottom housing 4 is assembled to the needle cover 3 and can pass over the proximal stop 334 of the guiding track 33 when the user presses the needle cover 3 against the injection site.

[0078] The guiding member includes a guiding pin 41 shaped to engage the guiding track 33 of the needle cover 3 to guide movements of the needle cover 3 relative to the bottom housing 4. The guiding pin 41 radially inwardly protrudes from the guiding member 41 and may be arranged at the distal end of the guiding member 41. The guiding pin 41 may include a distal abutment surface 414 and an inclined wall 415. With reference to Figures 23-24, the proximal abutment surface 42 is configured for axially abutting against the radial flange 23 of the barrel 20. This helps control the sticking depth and to secure the medical container 2 within the bottom housing 4.

[0079] The proximal abutment surface 42 may be delimited by a proximal side of an inner ring 421. The inner ring 421 may be located at the proximal end 403 of the bottom housing 4. The inner ring 421 delimits an opening 423 that allows for insertion of the barrel 20 in the bottom housing 4. As illustrated in Figures 23-24, the inner ring 421 and the bottom housing 4 are two distinct parts. The inner ring 421 may be removably attached to the bottom housing 4 by means of snap-fit features 425, which may be in the form of resilient hooks that may be configured to removably engage a window 405, Figure 21 , provided through the lateral wall 40 of the bottom housing 4. The opening 404 delimited by the proximal end 403 of the bottom housing 4 can thus be greater than the opening 423 defined by the inner ring 421 , in order to allow insertion of the needle cover 3 in the bottom housing 4 via the proximal end 403 of the bottom housing 4. The inner ring 421 may have orthoradial abutment surfaces 426 to prevent rotation with respect to the bottom housing 4. The orthoradial abutment surfaces 426 may be defined by axial walls 427 which delimit a gap for receiving the temporary blocking member 55 of the top housing 5. In an embodiment (not shown), the bottom housing 4 and the inner ring 421 may be made of a single piece, and the inner ring 421 may inwardly protrude from an inner surface of the lateral wall 40 of the bottom housing 4.

[0080] The inner ring 421 includes a distal supporting surface 424, Figure 24, configured to support a proximal end of the safety spring 7. The safety spring 7 is thus configured to extend around the barrel 20 of the medical container 2, between the distal supporting surface 424 of the bottom housing 4, more specifically of the inner ring 421 , and the proximal supporting surface 322 of the needle cover 3. The distal supporting surface 424 may be delimited by a distal side of the inner ring 421 . Thus, the proximal abutment surface 42 and the distal supporting surface 424 may be two opposite sides of the same inner ring 421 .

[0081] With reference to Figure 22, the blocking member 43 is configured for engaging the locker 35 of the needle cover 3 in order to block proximal movement of the needle cover 3 when the needle cover 3 is in the safety position. The blocking member 43 is in the form of an axially extending leg arranged within a window 431 provided through the lateral wall 40 of the bottom housing 4. The blocking member 43 has a proximal end 432 which is fixedly connected to the lateral wall 40 of the bottom housing 4 and an opposite distal end 433 which may be free to ease deformation of the blocking member 43. The guiding member 41 may be arranged near the distal end 401 of the bottom housing 4, i.e. at the distal portion of the bottom housing 4. In the initial position of the needle cover 3, the blocking member 43 is circumferentially offset the locker 35. In the safety position, the blocking member 43 and the locker 35 are no longer offset; they are axially aligned.

[0082] The blocking member 43 is resiliently deformable in an outward radial direction, between a rest position, in which the blocking member 43 is configured for blocking the needle cover 3 in the safety position, and a deformed position, in which the blocking member 43 flexes radially outwardly such that the blocking member 43 can pass over the inclined distal side of the locker 35 of the needle cover 3 when the needle cover 3 moves in the distal direction from the retracted position to the safety position.

[0083] The blocking member 43 includes a distal abutment surface 434 configured for axially abutting against the proximal abutment surface 356 of the needle cover 3 when the needle cover 3 is in the safety position. This abutment axially blocks the needle cover 3 in the safety position. The distal abutment surface 434 is defined by a distal side of an inward protrusion 435 which protrudes radially inwardly from the blocking member 43, at the distal end 433 thereof. The blocking member 43 also includes a proximal ramp 436 configured for easing deformation and passage of the blocking member 43 over the locker 35 of the bottom housing 4 when the needle cover 3 moves in the distal direction towards the safety position. The proximal ramp 434 is delimited by a proximal side of the inward protrusion 435.

[0084] With reference to Figures 10 and 21 , the proximal stop 44 is configured for axially abutting against a distal stop 550 of the top housing 5, such that the top housing 5 is prevented from moving in the distal direction with respect to the bottom housing 4. This permits to keep the bottom housing 4 and the top housing 5 axially locked during the pricking process, i.e. during penetration of the injection needle 21 into the injection site. As will be described below, the top housing 5 is however configured to pass over the proximal stop 44 when the pricking operation is completed, i.e. when the injection needle has reached the predetermined injection depth, so that injection of the medical product into the injection can start.

[0085] As illustrated in Figure 21 , the proximal stop 44 may delimit an opened notch 441 arranged at the proximal end of the bottom housing 4. The notch 441 is configured to receive the axial walls 427 of the inner ring 421 , and may thus be also delimited by two orthoradial surfaces 442 configured for abutting against the orthoradial surfaces of the inner ring 421 .

[0086] The fastener 45 is configured for allowing removable attachment of the bottom housing 4 to the top housing 5. To that end, the fasteners 45 of the bottom housing 4 are configured for engaging fasteners, such as side windows 54, of the top housing 5.

[0087] The fastener 45 of the bottom housing 4 may be in the form of an axially extending resilient leg which is arranged inside a window 405 provided through the lateral wall 40 of the bottom housing 4. The fastener 45 may include a distal end 452, fixed to the lateral wall 40 of the bottom housing 4, a proximal end 453, which may be free, a distal abutment surface 454 configured for axially abutting against a proximal abutment surface of the top housing 5, and an outer pressing portion 456 configured for receiving an inward radial pressure of the user. The resilient leg 45 may be movable between a blocking (rest) position, Figure 6, in which the distal abutment surface 454 of the fastener axially abuts against the proximal abutment surface of the top housing 5, such that the top housing 5 cannot be removed from the bottom housing 4, and a release (deformed) position, radially inwardly located with respect to the blocking position, in which the distal abutment surface 454 of the fastener 45 is shifted away from the proximal abutment surface of the top housing 5, such that the top housing 5 can be moved in the proximal direction and can thus be withdrawn from the bottom housing 4. Movement of the fastener 45 from the blocking position to the release position is caused by the user exerting an inward radial pressure on the outer pressing portion 456 of the fasteners such that the fasteners 45 radially inwardly flex.

[0088] The distal abutment surface 454 may be arranged at a distal side of a protrusion that outwardly radially protrudes from the resilient leg 45, more specifically at the proximal end 453 thereof. The protrusion may include an inclined proximal side 455 configured to ease assembly of the bottom housing 4 to the top housing 5. Opposite the protrusion, the proximal end 453 may have a slanted inner wall 457, Figure 6, to leave room for the inward deformation of the fastener 45 without interfering with the safety spring 7.

[0089] The outer pressing portion 456 may include reliefs, such as alternate ribs and grooves which extend orthogonal to the longitudinal axis A so that avoid the user’s fingers to slide along the resilient leg 45 when the user presses the resilient leg to remove the top housing 5 from the bottom housing 4. The outer pressing portion 456 may for instance extend at the middle of the resilient leg 45.

[0090] The fastener 45 and the bottom housing 4 may be made of a single piece.

[0091] With reference to Figures 4 and 25-26 is shown the top housing 5. The top housing 5 is configured for allowing the user to hold the injection device 10 in his / her hand. The top housing 5 is also configured for being removably attached to the bottom housing 4 so that the user can remove the used medical container 2 from the bottom housing 4 and replace it by a new (not yet used) one. The top housing 5 is further configured to push the stopper 25 inside the barrel 20 in order to expel the medical product into the injection site via the injection needle 21 . The top housing 5 is in the form of an elongated tube extending along the longitudinal axis A and configured for surrounding the bottom housing 4. The top housing 5 is removably attached to the proximal end of the bottom housing 4.

[0092] The top housing 5 includes a lateral wall 50 defining an inner cavity for receiving the bottom housing 4, a distal end 501 delimiting an opening configured for receiving the bottom housing 4, a closed proximal end 502, a movable washer 51 , biasing means such as a spring 52 for moving the washer, and a plunger rod 53 for pushing the stopper 25 and for guiding movement of the washer 51 . The top housing 5 also includes a fastener 54 for removable attachment of the top housing 5 to the bottom housing 4, and a temporary blocking member 55 for blocking axial movement of the top housing 5 with respect to the bottom housing 4 before injection.

[0093] The top housing 5 is axially movable with respect to the bottom housing 4 between an initial position, Figure 4, in which the temporary blocking member 55 axially abuts against the proximal stop 44 of the bottom housing 4 and in which the plunger rod 53 has not yet begun to push the stopper 25, so that the top housing 5 is axially blocked with respect to the bottom housing 4 to allow for insertion of the injection needle 21 into the injection site before injection of the medical product, and an injection position, Figures 12-13, distally located with respect to the initial position, in which the plunger rod 53 is configured for pressing the stopper 25 against the distal end of the reservoir formed by the barrel 20 so that the injection is completed. In the initial position, the bottom housing 4 mainly extends outside the top housing 5 whereas in the injection position, the bottom housing 4 may be fully contained inside the top housing 5. Movement of the top housing 5 from the initial position to the injection position is caused by the user pressing the injection device 10 against the injection site. Movement of the top housing 5 from the injection position back to the initial position is caused by biasing means such as the spring 52.

[0094] The temporary blocking member 55 is in the form of a straight resilient leg which extends along the longitudinal axis A and which may be arranged in a lateral window provided through the lateral wall 50 of the top housing 5. As illustrated in Figure 9, the resilient leg 55 includes a proximal end 552 fixed to the lateral wall 50 of the top housing 5, an opposite free distal end 551 , a distal stop 550 configured for axially abutting against the proximal stop 44 of the bottom housing 4 as long as the top housing 5 is in the initial position, a distal ramp 553 and a proximal ramp 554. The distal stop 550 may be a flat surface delimited by at a front portion of the proximal end 552 of the resilient leg 55. The distal ramp 553 may be arranged at a distal side of an inner protrusion which radially inwardly protrudes from an inner surface of the resilient leg 55. A proximal side of the inner protrusion may define the proximal ramp 554. The inner protrusion may be located at the proximal end 552 of the resilient leg 55. The distal ramp 553 and the proximal ramp 554 are configured to ease deformation of the resilient leg 55. The temporary blocking member 55 may further include a buttress 555 arranged on an inner surface of the resilient leg 55 and axially extending from the inner protrusion in a proximal direction for reinforcing the flexible leg 55.

[0095] The temporary blocking member 55 is radially movable between a blocking (rest) position, Figures 10 and 14, in which the distal stop 550 of the top housing 5 axially abuts against the proximal stop 44 of the bottom housing 4 to maintain the top housing 5 in the initial position, and a release (deformed) position, in which the resilient leg 55 deforms radially outwardly so that the distal stop 550 is shifted away from the proximal stop 44 of the bottom housing 4, thereby allowing the top housing 5 to move distally with respect to the bottom housing 4 in order to perform injection. Movement of the temporary blocking member 55 to the release position is caused by the injection-triggering member 39 of the needle cover 3 which presses against the distal ramp 553 of the temporary blocking member 55 when the needle cover moves to the retracted position, as illustrated in Figure 14. Movement of the temporary blocking member 55 back to the initial position is caused by the resiliency of the resilient leg 55 when the top housing 5 moves back to the initial position so that the inner protrusion of the temporary blocking member 55 no longer radially abuts against the lateral wall of the bottom housing 4. In the blocking position, the temporary blocking member 55 may be slightly inclined towards the central longitudinal axis A. With reference to Figures 33 and 34, it is contemplated that the length of the temporary blocking member 55 may vary to set the effort required for injection activation.

[0096] As illustrated in Figure 25, the fastener 54 may be a window arranged through the lateral wall 50 of the top housing 5 for removably receiving the fastener 45 of the bottom housing 4. The window may be provided near the distal end 501 of the top housing 5. The window provides the user with a visual indication that the bottom housing 4 is connected to the top housing 5.

[0097] As visible in Figures 4 and 25-26, the plunger rod 53 is in the form of a hollow or full shank which may be cylindrical and which extends along the longitudinal axis A. The plunger rod 53 has a proximal end fixed to the transversal wall 503 of the proximal end 502 of the top housing 5 and a distal end 530 configured for pushing the stopper inside the barrel. When the plunger rod 53 is hollow, a proximal opening 531 may be delimited at the proximal end of the top housing 5. The plunger rod 53 may include an axial slot 532 for guiding axial movement of the washer 51 , as will be explained below. The axial slot 532 ends at a proximal stop 533 configured for stopping distal movement of the washer 51 . The plunger rod 53 may include two diametrically opposite axial slots 532.

[0098] The spring 52, arranged around the plunger rod 53, includes a proximal end supported by the transversal wall 503 of the proximal end of the top housing 5 and a distal end distally pushing against a proximal supporting surface 510 of the washer 51 . The spring 52 is configured for distally pressing the washer 51 against the flange 23 of the medical container 2 or against the proximal stop 533 of the plunger rod 53.

[0099] As illustrated in Figures 27-28, the washer 51 is in the form of a plate-shaped ring having a central opening 511 for allowing passage of the plunger rod 53, a distal side including a distal abutment surface 512 for axially abutting against the flange 23 of the barrel 20 when a medical container 2 is mounted inside the safety device 1 , or against the proximal stop 533 of the axial slot 532 when the top housing 5 is separated from the bottom housing 4. The washer 51 may be symmetrical with respect to a plane orthogonal to the longitudinal axis A. The washer 51 includes one or two diametrically opposite guiding members 513 configured for engaging the axial slots 532 of the plunger rod 53 so as to guide axial movement of the washer with respect to the plunger rod 53. The guiding members 513 may be in the form of radial tabs which may inwardly radially protrude from two radial ears 514 of the washer, inside a radial notch 515 delimited by said ears 514. The radial tabs have a fixed outer end and a free inner end. The proximal supporting surface 510 of the washer may be arranged on a proximal side of the radial tabs 513. The radial tabs 513 may further include one or more recesses 516 that ease deformation of the tabs to allow mounting of the washer 51 onto the plunger rod 53.

[0100] The washer 51 is axially movable with respect to the plunger rod 53, between an initial position, Figure 4, in which the distal abutment surface 512 of the washer pushes the flange 23 of the barrel 20 against the proximal abutment surface 42 of the bottom housing 4 such that the medical container is reliably maintained within the safety device 1 , and an injection position, Figure 13, proximally located with respect to the initial position, which corresponds to the injection position of the plunger rod 53, i.e. when the injection is over. When the bottom housing 4 and the top housing 5 are disassembled, the washer 51 may also move to a rest position (not shown), which may be distally located with respect to the initial position, in which the washer 51 axially abuts against the proximal stop 533 of the axial slot 532. This avoids separation of the washer 51 from the top housing 5. Movement of the washer 51 from the initial position to the injection position is due to the user pressing the top housing 5 towards the injection site to perform injection, when the top housing 5 can move distally relative to the bottom housing 4 to have the plunger rod 53 distally push the stopper 25. Movement of the washer 51 back in the distal direction is due to the spring 52.

[0101] It is contemplated that the top housing 5 and the plunger rod 53 may be made of a single piece. The washer 51 may be a separate component.

[0102] The operation of the injection device 10 is described below.

[0103] In Figures 3-7, the needle cover 3 is in the initial position. The top housing 5 is in the initial position so that the top housing 5 and the bottom housing 4 are axially secured to each other. The medical container 2 is axially maintained within the bottom housing 4 by means of the washer 51 in the initial position, pressed against the flange 23 by the spring 52. The blocking member 43 of the bottom housing 4 and the locker 35 are still offset at this stage (they do not axially face each other). The guiding pin 41 abuts against the initial distal stop 333 of the guiding track 33.

[0104] The needle shield 22 may, or may not, slightly extend distal to the distal end 31 of the needle cover 3. In order to remove the needle shield 22, the user may thus either directly grab the needle shield 22 or first slightly push the needle cover 3 in the proximal direction to unveil the needle shield 22 and then grab it. As a result of the needle cover 3 being pushed by the user, the guiding pin 41 , which was abutting against the initial distal stop 333, moves towards the proximal stop 334 of the first portion 332a of the guiding track 33. The proximal stop 334 prevents the needle cover 3 from going too far towards the retracted position and possibly inadvertently reaching the safety position whereas the injection has not yet been performed. After removal of the needle shield 22, the needle cover 3 may move back to the initial position to protect the needle 21 before injection, see Figure 6. The injection needle 21 does not extend distally beyond the distal end 31 of the needle cover 3.

[0105] When the user is ready to perform the injection operation, he / she may hold the top housing 5 in one hand and press the distal end 31 of the needle cover 3 against the injection site, until the injection needle 21 reaches the right pricking and injection depth, Figure 8. During the proximal movement (retraction) of the needle cover 3 within the bottom housing 4, the guiding pin 41 slides against the connecting portion 338a which causes a slight rotation of the needle cover 3. The penetration of the injection needle 21 ends when the needle cover 3 cannot move further in the proximal direction, i.e. when the needle cover 3 reaches the retracted position. The guiding pin 41 now abuts against the injection-depth defining member 339, Figure 11. The injection needle 21 is at the right injection depth. That is, the user does not have to select the injection depth, which is already set by the injection device 10. Besides, there is very small dispersion of the pricking and injection depth because this pricking and injection depth depends on three axial dimensions only, Figure 8: the distance d1 between the distal end of the injection needle 21 and the radial flange 23 of the barrel 20, the distance d2 between the distal end 31 of the needle cover 3 and the injection depth defining member 339 which abuts against the distal abutment surface 414 of the guiding pin 41 , and the distance d3 between the distal abutment surface 414 of the guiding pin 41 and the proximal abutment surface 42 of the bottom housing 4 which abuts against the radial flange 23 of the barrel 20. The difference between d1 and the sum of d2 plus d3 is the pricking depth.

[0106] Until then, the abutment between the temporary blocking member 55 of the top housing 5 and the bottom housing 4 had prevented that injection begins before the injection needle 21 reaches the right pricking depth. As shown in Figures 10 and 14, when the needle cover 3 reaches the retracted position, the injection-triggering member 39 abuts against the temporary blocking member 55 of the top housing 5, thereby causing movement of the temporary blocking member 55 to the release position. As a result, the top housing 5 can now slides onto the bottom housing 4.

[0107] The user can then perform the injection operation by exerting a further distal push on the top housing 5, which accordingly leaves the initial position and moves axially with respect to the bottom housing 4 towards the injection position. The plunger rod 53, fixed to the top housing 5, consequently moves within the barrel 20 and pushes the stopper 25 in the distal direction, so that the medical product contained in the medical container 2 is expelled from the barrel 20 into the injection site via the injection needle 21 , Figures 12-13.

[0108] When the injection operation is completed, the user removes the injection device 10 from the injection site. As a result, the safety spring 7 pushes the needle cover 3 back in the distal direction towards the safety position. Thus, the guiding pin 41 moves along the second portion 332b of the guiding track 33 towards the proximal end of this second portion 332b. It is contemplated that, due to rotation of the needle cover 3, the locker 35 of the needle cover 3 and the blocking member 43 are now aligned; more specifically, the blocking member 43 of the bottom housing 4 is now in the axial path of the locker 35 of the needle cover 3. Therefore, they come into contact against each other. Due to the pressure of the safety spring 7, the locker 35 causes outward deformation of the blocking member 43 which accordingly passes over the locker 35. The needle cover 3 then reaches the safety position: the proximal abutment surface 356 of the needle cover 3 now abuts against the distal abutment surface 434 of the bottom housing 4, thereby preventing proximal movement of the needle cover 3, and the final distal stop 337 of the guiding track 33 abuts against the guiding pin 41 of the bottom housing 4, thereby preventing distal movement of the needle cover 3; As a result, the needle cover 3 is locked in the safety position. Since the distal end 31 of the needle cover 3 extends distally beyond the distal end of the injection needle 21 , needle stick injuries are prevented.

[0109] Having said that, it is important to notice that the safety device 1 is a re-usable safety device 1 , which can thus be re-used with another (not yet used) medical container 2 to perform another injection operation. But since the needle cover 3 is axially locked in the safety position, as we have seen before, the safety device 1 needs to be reset.

[0110] The method for resetting the safety device 1 according to the invention, in order to re-use the safety device 1 , is described below.

[0111] The user may first put the needle shield 22 back onto the used medical container 2. This is accomplished by inserting the needle shield 22 through the distal opening formed at the distal end of the needle cover 3 and pushing the needle shield 22 in the proximal direction. This step has the advantage to prevent any accidental needle stick injury between the removal of the used medical container 2 from the device 1 and the disposal of the used medical container 2 in a sharps container.

[0112] In order to remove the used medical container 2, the user has to disassemble the top housing 5 and the bottom housing 4. To that end, the user exerts an inward radial pressure on the fasteners 45 of the bottom housing 4 such the fasteners 45 move to the release position. While maintaining the pressure on the fasteners 45, the user can move the top housing 5 in the proximal direction to separate the top housing 5 from the bottom housing 4. The washer 51 no longer abuts against the flange 23 of the medical container 2, but abuts against the proximal stop 533 of the plunger rod 53 to stay assembled to the top housing 5. The used medical container 2 can now be removed from the bottom housing 4 and discarded.

[0113] The safety device 1 is ready to accommodate a new (not yet used) medical container 2 which can be inserted inside the bottom housing 4 and the needle cover 3. The user can then put the top housing 5 back onto the bottom housing 4 by inserting the bottom housing 4 through the opened distal end of the top housing 5 and moving the top housing 5 in the distal direction. The distal end of the top housing 5 abuts against the fastener 45 of the bottom housing 4, which deforms in an inward radial direction so that the top housing 5 can pass over the fastener 45 until the fastener 54 of the top housing 5 and the fastener 45 of the bottom housing 4 engage with each other. The top housing 5 is back to the initial position and therefore axially locked with respect to the bottom housing 4. During this assembly, the plunger rod 53 may penetrate into the barrel 20 and the washer 51 comes against the flange 23 of the new medical container 2 to axially secure this new medical container 2 against the proximal abutment surface 42 of the bottom housing 4.

[0114] In order to complete the resetting process, the user has to rotate the needle cover 3 with respect to the bottom housing 4 so that the guiding pin 41 of the housing 4 moves along the second connecting portion 338b of the guiding track 33, from the safety position towards the initial position. When the guiding pin 41 orthoradially abuts against the lateral side 336a of the guiding track 33, Figure 20B, rotation of the housing 4 relative to the needle cover 3 stops. The guiding pin 41 may be positioned against the initial distal stop 333 and the shoulder 336b. The needle cover 3 is back to the initial position and ready for re-use. It is contemplated that the rotation of the needle cover 3 back to the initial position can otherwise be done before assembling the top housing 5 back to the bottom housing 4.

[0115] The safety device 1 of the invention thus permits to be re-used instead of being discarded together with the used medical container 2, which improves sustainability. This reusable feature of the safety device 1 invention of the invention is not accompanied by a complexification of the safety device 1 , instead the safety device 1 of the invention remains simple to use, assemble and manufacture.

[0116] With reference to Figure 29 is shown another embodiment of the invention. In this embodiment, all the elements, including the medical container 2, the top housing 5, and the bottom housing 4, may be similar to those described above, except for the needle cover 3. The same features are designated with the same numeral references.

[0117] Here in Figure 29, the guiding track 33 does not include the resetting portion 338b. Instead, the second portion 332b has a closed proximal end. The guiding pin 41 is thus prevented to move in a rotational direction when the needle cover 3 is in the safety position. The delimiting rib 330a here defines orthoradial abutment surfaces 38 for preventing rotation of the needle cover 3 relative to the housing 4 when the guiding pin 41 is at the proximal end of the second portion 332b of the guiding track 33, i.e. when the needle cover 3 is in the safety position. Moreover, the delimiting rib 330a is a continuous rib. The guiding track 33 includes a single delimiting rib 330a. The proximal end 335 of the first portion 332a is closed and the guiding track 33 includes a mounting rib 330c.

[0118] Still with reference to Figure 29, the locker 35 is no longer in the form of a fixed protrusion. Instead, the locker 35 is radially movable between a deactivated position, in which the locker 35 cannot axially abut against the housing 4 and in which the locker 35 accordingly allows the needle cover 3 to move back from the safety position to the initial position, and an activated position, in which the locker 35 axially abuts against the housing 4 so that the needle cover 3 cannot move back in the proximal direction and leave the safety position. For instance, the locker 35 is in the form of a resilient hook which includes a resilient leg 351 that may outwardly radially deform between a rest position, in which the hook does not radially protrude over the lateral wall 30 of the needle cover 3 so that the hook cannot engage the housing 4, and a deformed position, in which the hook outwardly radially protrudes over the lateral wall 30 of the needle cover 3 so that the hook can engage the housing 4. The rest position thus corresponds to the deactivated position while the deformed position may correspond to the activated position. The resilient leg 351 may form resetting means for allowing reset, and thus re-use, of the safety device 1 , as will be seen in further details below. Movement of the locker 35 from the deactivated position to the activated position is caused by the barrel 20 of the medical container 2 being introduced within the housing 4 such that the barrel 20 radially outwardly pushes against a lateral wall 357 of the locker 35. Movement of the locker 35 from the activated position to the deactivated position is caused by removal of the used medical container 2 from the housing 4. It is thus readily understandable that the needle cover 3 cannot be moved back from the safety position to the initial position, and the safety device 1 cannot be re-used as long as the used medical container 2 is located within the housing 4.

[0119] The locker 35 may longitudinally extend parallel to the longitudinal axis A, within a lateral opening 352 provided through the lateral wall 30 of the needle cover 3. The locker 35 has a proximal end 353 and a distal end 354; the proximal end 353 may be secured to the lateral wall 30 of the needle cover 3 while the distal end 354 may be free. The distal end 354 includes an outward radial protrusion 355 whose distal side may be inclined to ease passage of the blocking member 43 of the housing 4 over the locker 35 when the needle cover 3 moves from the retracted position to the safety position. A proximal side of this outward radial protrusion 355 defines a proximal abutment surface 356. The proximal abutment surface 356 of the locker 35 is configured for axially abutting against the housing 4 when the needle cover 3 is in the safety position. Therefore, the locker 35 prevents proximal movement of the needle cover 3 when the needle cover 3 is in the safety position. This protects the user against needle sticks.

[0120] The operation of the injection device 10 including the needle cover of Figure 29 is similar to the operation described with reference to Figures 1-28. However, the method for resetting the safety device 1 differs. At the end of the injection process, the guiding pin 41 is here locked against the final distal stop 337 and cannot return towards the initial position by a mere rotation because the guiding track 33 does not include here the resetting portion 338b. The only way to reset the safety device is to move the guiding pin 41 back in the distal direction with respect to the needle cover 3, i.e. along the second portion 332b towards the injection-depth defining member 339 from the safety position to the retracted position, then along the connecting portion 338a, and then along the first portion 332a, from the retracted position to the initial position, until the guiding pin 41 abuts against the initial distal stop 333. However, the user must first remove the used medical container 2 so that the locker 35 can retract in the needle cover 3 in order to allow the needle cover 3 to move back in the proximal direction. Therefore, the resetting of the needle cover 3 becomes possible only after removal of the used medical container 2. During this movement, the needle cover 3 also rotates from the activated rotational position to the armed rotational position. The locker 35 and the blocking member 43 thus become rotationally distant; they no longer axially face each other.

[0121] Once the needle cover 3 is back to the initial position, the safety device 1 is ready to accommodate a new (not yet used) medical container 2, i.e. is ready to be re-used. When the user introduces a new medical container 2 within the bottom housing 4, this moves the locker 35 radially outwardly back to the activated position. The user can then put the top housing 5 back onto the bottom housing 4 by inserting the bottom housing 4 through the opened distal end of the top housing 5 and moving the top housing 5 in the distal direction. The distal end of the top housing 5 abuts against the fastener 45 of the bottom housing 4, which deforms in an inward radial direction so that the top housing 5 can pass over the fastener 45 until the fastener 54 of the top housing 5 and the fastener 45 of the bottom housing 4 engage with each other. The top housing 5 is back to the initial position and therefore axially locked with respect to the bottom housing 4. During this assembly, the plunger rod 53 may penetrate into the barrel and the washer comes against the flange of the medical container to axially secure the medical container against the proximal abutment surface of the bottom housing 4. The injection device 10 is ready for reuse. An injection operation can be performed with the new medical container 2 equipped with the re-usable safety device 1 .

[0122] The safety device 1 of the invention thus permits to be re-used instead of being discarded together with the used medical container 2, which improves sustainability. This reusable feature of the safety device 1 invention of the invention is not accompanied by a complexification of the safety device 1 , instead the safety device 1 of the invention remains simple to use, assemble and manufacture.

[0123] With reference to Figure 30 is shown a guiding track 33 including a connecting portion 338a having a rounded shape between the distal end of the first portion 332a and the distal end of the second portion 332b instead of extending a straight direction. The shape of the connecting portion 338a is not limited to a curved or straight direction, and may include any variant that allows for the guiding pin 41 to pass from the first portion 332a to the second portion 332b while possibly further causing rotation of the needle cover 3 from the armed rotational position to the activated rotational position.

[0124] With reference to Figures 31-32, the injection device 10 can include a cap 6 configured for removing the needle shield 22.

[0125] The cap 6 has a tubular wall 61 defining an inner cavity leading to an opened distal end and 62 an opposite opened proximal end 63. The opened distal end 62 allows for ejection of the needle shield 22 from the cap 6. The opened proximal end 63 is configured for allowing insertion of the needle shield 22 and the distal end 31 of the needle cover 3 within the cap 6. The cap 6 has a retainer 64 configured removable attachment of the cap 6 to the needle cover 3 and a remover 65 for pulling the needle shield 22 off the medical container 2.

[0126] The retainer 64 is in the form of a hook having an inclined proximal side and a distal side defining a distal abutment surface 641 configured for axially abutting against a proximal stop 34 of the needle cover 3. The proximal stop 34 may be arranged at a proximal side of the circumferential ring 312 of the needle cover 3.

[0127] The remover 65 may be a flexible leg provided with a distal abutment surface for axially abutting a proximal stop 221 of the needle shield 22. The proximal stop may be located at a distal end 223 of the needle shield 22.

[0128] Before performing an injection operation, the user has to remove the cap 6 from the needle cover 3, by pulling the cap 6 in the distal direction. Due to the remover 65, withdrawal of the cap 6 entails simultaneous withdrawal of the needle shield 22 from the medical container 2. The user has then to carry out the above-described steps to perform injection.

[0129] It is readily understandable from the above description that the safety device 1 of the invention is re-usable and therefore provides an improved sustainability. The injection device 10 that includes this re-usable safety device 1 allows for performing a manual injection operation, while benefitting from an automatic activation of the safety device 1. 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

CLAIMS1. Safety device (1) configured for preventing needle sticks, the safety device (1) including: a bottom housing (4), extending along a longitudinal axis A and configured for accommodating a medical container (2) provided with an injection needle (21); a top housing (5) configured to be connected to the bottom housing (4) in order to axially block the medical container (2) inside the bottom housing (4), fasteners (45, 54) configured for allowing removable attachment of the bottom housing (4) to the top housing (5) so that the medical container (2) can be removed, a needle cover (3), movable with respect to the bottom housing (4) between an initial position, a retracted position, proximally located with respect to the initial position, and a safety position, distally located with respect to the retracted position, in which a proximal abutment surface (356) of the needle cover (3) abuts against a blocking member (43) of the bottom housing (4) such that the needle cover (3) cannot move back in the proximal direction, a guiding pin (41) configured for engaging a guiding track (33) to guide axial and rotational movement of the needle cover (3) from the initial position to the safety position, resetting means (338b, 351) configured for allowing disengagement of the proximal abutment surface (356) and the blocking member (43) and movement of the guiding pin (41) back from the safety position to the initial position after removal of the medical container (2).

2. Safety device (1) according to the preceding claim, wherein the top housing (5) includes a temporary blocking member (55) which is radially movable between a blocking position, in which the temporary blocking member (55) distally abuts against the bottom housing (4) such that the top housing (5) cannot distally move with respect to the bottom housing (4), and a release position, in which the temporary blocking member (55) no longer axially abuts against the bottom housing (4) so that the top housing (5) can move in the distal direction with respect to the bottom housing (4).

3. Safety device (1) according to the preceding claim, wherein the needle cover (3) includes an injection-triggering member (39) configured for abutting against the temporary blocking member (55) of the top housing (5) such that the temporary blocking member (55) moves to the release position.

4. Safety device (1) according to any of the preceding claims, wherein the plunger rod (53) is fixed to the top housing (5).

5. Safety device (1) according to any of the preceding claims, wherein the top housing (5) includes an axially movable distal abutment surface (512) configured for axially abutting against a flange (23) of the medical container (2), and biasing means configured for pressing the distal abutment surface (512) of the top housing (5) against the flange (23) of the medical container (2).

6. Safety device (1) according to any of the preceding claims, wherein the bottom housing (4) includes a proximal abutment surface (42) configured for axially abutting against a flange (23) of the medical container (2), and a distal abutment surface (414) configured for axially abutting against an injection-depth defining member (339) of the needle cover (3).

7. Safety device (1) according to any of the preceding claims, wherein the top housing (5) is removably attached to the bottom housing (4).

8. Safety device (1) according to any of the preceding claims, wherein the bottom housing (4) includes a resiliently deformable fastener (45) for attaching the bottom housing (4) to the top housing (5), and the resiliently deformable fastener (45) includes an outer pressing portion (456) allowing a user to radially inwardly deform the resiliently deformable fastener (45) from a blocking position, in which the resiliently deformable fastener (45) prevents removal of the top housing (5) from the bottom housing (4), to a release position, in which the top housing (5) can be removed from the bottom housing (4).

9. Safety device (1) according to any of the preceding claims, wherein the resetting means include a resetting portion (338b) of a guiding track (33) engaged by a guiding pin (41), the resetting portion (338b) being configured for guiding movement of the needle cover (3) from the safety position to the initial position by rotation of the needle cover (3) with respect to thebottom housing (4) around the longitudinal axis A without need for the needle cover (3) to move back in the proximal direction with respect to the bottom housing (4).

10. Safety device (1) according to any of the preceding claims 1-8, wherein the resetting means include a resilient leg (351) and the resilient leg (351) includes the proximal abutment surface (356) of the needle cover (3), the resilient leg (351) being radially deformable between a blocking position, in which the proximal abutment surface (356) abuts against the blocking member (43) of the bottom housing (4), and a release position, radially inwardly located with respect to the blocking position, in which the proximal abutment surface (356) is shifted away from the blocking member (43), such that the needle cover (3) can move back in the proximal direction from the safety position to the retracted position.11 . Safety device (1) according to any of the preceding claims, wherein the safety device (1) includes a cap (6) removably attached to a distal end (31) of the needle cover (3), the cap (6) including a remover (65) configured for removing a needle shield (22) of the medical container (2).

12. Injection device (10) including the safety device (1) according to any of the preceding claims, and a medical container (2) arranged within the housing (4) of this safety device (1).

13. Method for re-setting the safety device (1) according to any of the preceding claims 1-11 , the method comprising the steps of: removing a medical container (2) from the bottom housing (4); moving the needle cover (3) from the safety position to the initial position.

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