CN214050038U

CN214050038U - Drug delivery device

Info

Publication number: CN214050038U
Application number: CN202020492815.7U
Authority: CN
Inventors: 斯特凡·梅尔; 克里斯蒂安·施鲁尔; 于尔格·赫歇尔
Original assignee: Yipeisheng Co
Current assignee: Yipeisheng Co
Priority date: 2020-04-07
Filing date: 2020-04-07
Publication date: 2021-08-27
Anticipated expiration: 2030-04-07
Also published as: CH715854A2

Abstract

The utility model relates to a drug delivery device (1), including shell (10), with shell (10) releasable connected carpule anchor clamps (13), plunger rod (60), drive sleeve (40), can be for shell (10) pivoted first coupling piece (90), can be for shell (10) axial displacement's second coupling piece (110) and with the antitorque connection of plunger rod (60) and can be for plunger rod (60) and shell (10) axial displacement's third coupling piece (120). The cartridge holder (13) can be connected to or disconnected from the housing (10) by at least one rotational movement relative to the housing (10), wherein the first coupling part (90) is rotated by the rotational movement. The first and second links (90, 110) are coupled to each other using a cam mechanism such that rotation of the first link (90) produces axial movement of the second link (110). The third coupling member (120) is rotationally coupled to or decoupled from the drive sleeve (40) by axial movement.

Description

Drug delivery device

Technical Field

The utility model relates to the field of medical drug delivery devices for the delivery of liquid substances, in particular drugs or medical substances like insulin and hormone preparations. The utility model relates to a drug delivery device with a connecting mechanism.

Background

The known syringe comprises a housing with a dosing and pouring mechanism and a kapur clamp. The clip is coupled to the housing and retains the carpule containing the medical substance.

To adjust the dose, the user rotates or pulls on a dose piece of the dose and pour mechanism, wherein the dose piece is at the same time rotated or moved out of the housing of the syringe. In order to allow the dose thus adjusted to be poured out, the user presses a pouring button on the proximal end of the syringe and thereby generates a force in the proximal direction, whereby the dosage element is screwed or moved into the housing. The difference with the dose setting is that in the tilting-out aspect, a rotation or movement is transferred to the drive sleeve or coupling sleeve, which thereby drives the plunger rod in order to tilt out the substance from the carpule. Depending on the implementation, the plunger rod is supported in a rotatable or screwed or only movable manner with respect to the housing.

The disposable injection device (disposable) is discarded after pouring out the full volume from the carpule. In the case of a reusable injection device, the carpule in the injection device can be replaced by a new carpule. For this purpose, the cartridge holder is separated from the housing so that the cartridge can be replaced. Furthermore, the plunger rod in the proximal position must be retracted back into the distal position in order to prepare the injection device for pouring a new full volume of carpule. The removed carpule is typically pushed back into the housing of the injection device in a distal direction by the user. However, for this purpose, the plunger rod must be disengaged from the transmission element (e.g., transmission sleeve) since the normally present one-way ratchet (e.g., in the form of a rotational lock) prevents the plunger rod from moving back. This selective connection of the plunger rod to the dose and pouring mechanism transmission element or the disengagement of the plunger rod from the transmission element may be performed by a retraction mechanism or a reset mechanism.

That is, such a retraction mechanism must on the one hand allow the plunger rod to be moved back into the starting position in the housing when the carpule clamp is removed from the housing, and on the other hand, if the carpule clamp is fully connected to the housing, the plunger rod can be connected to the transmission element, so that the tilting movement of the tilting element is reliably transferred to the plunger rod.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to realize the reliable callback of the device of dosing when changing carpule in the device of dosing that can repetitious usage.

According to the present invention, for pouring out a dose of product from a carpule held in a drug delivery device, the drug delivery device, in particular an injection device, comprises: a housing defining an axial or longitudinal axis, a carpule holder releasably connected to a proximal end of the housing, a plunger rod, and a drive sleeve for driving the plunger rod in a distal direction for tilting the article from the carpule. The drug delivery device according to the invention furthermore comprises a first coupling member which is rotatable relative to the housing, a second coupling member which is axially movable relative to the housing and a third coupling member which is connected with the plunger rod in a rotationally fixed manner and which is axially movable relative to the plunger rod and the housing. In this aspect, the kapur clamp is attachable to or detachable from the housing by at least one rotation relative to the housing. The first and second coupling members are coupled to each other by a cam mechanism configured such that rotation of the first coupling member produces axial movement of the second coupling member, wherein the axial movement produces axial movement of the third coupling member. The third coupling member is rotationally coupled to or decoupled from the drive sleeve by axial movement.

The cartridge holder is fixed to the housing at least by means of a rotational movement (or a combination of a rotational movement and an axial movement) relative to the housing, for example by means of a screw connection or by means of a bayonet connection.

A rotational movement of the kapur clamp relative to the housing can be transferred in a simple manner into a linear, axial displacement movement of the second coupling member by means of a cam mechanism.

If the third coupling member, which selectively rotationally couples or decouples the drive sleeve to the plunger rod, directly interacts with the carpule holder, there is a risk that the third coupling member will be accidentally turned. Since the third coupling part is connected to the plunger rod in a rotationally fixed manner, the plunger rod is also rotated as a result, which can lead to an accidental pouring or an accidental rearward movement of the flange.

However, according to the invention, the third coupling member (rotationally coupled to the plunger rod) is operated by a pure axial movement, so that the drive sleeve is rotationally coupled to or decoupled from the plunger rod, and accidental rotation of the plunger rod is reliably avoided.

The first and second coupling members are coupled to each other using a cam mechanism. The cam mechanism may convert or translate rotational movement of the first coupling member into axial movement of the second coupling member. In this respect, it is preferred that the second coupling member is only axially displaceable and not rotatable.

The cam mechanism preferably comprises a rack cam and a branch point link, wherein one of the first or second coupling members forms the rack cam and the other of the first or second coupling members comprises the branch point link. In this respect, the cam carrier defines a movement path and/or a movement direction in advance, and the branching point link is forced along the predetermined movement path and/or the predetermined movement direction by the curve or the shape of the cam carrier.

To replace the carpule, the carpule clamp may be loosened or separated therefrom with at least one rotational movement relative to the housing. The first coupling member is also preferably rotated by a rotational movement. The cam mechanism converts this rotational movement of the first coupling member into an axial displacement movement of the second coupling member, preferably while the second coupling member is moved in the distal direction. Whereby the third coupling member, which is axially connected to the second coupling member, is also moved distally. By this movement, the third coupling part no longer engages with the drive sleeve. The plunger rod and the third coupling member may then be rotated relative to the drive sleeve. The plunger rod may then be displaced from the distal end back to the proximal starting position.

After the plunger rod is returned and replaced with carpule, the carpule clamp is reconnected to the housing. To connect the kapur clamp to the housing, the first coupling member is rotated back. The cam mechanism converts this rotational movement of the first coupling member into an axial displacement movement of the second coupling member, preferably in the proximal direction. The third coupling element, which is axially connected to the second coupling element, is thereby likewise axially moved proximally. The third coupling part thus engages again with the drive sleeve. The third coupling member thus rotationally couples the drive sleeve with the plunger rod, so that a rotational movement is transmitted by the drive sleeve to the plunger rod.

The administration device is preferably designed as an injection device and particularly preferably as a multiple-use injection device (also referred to as "reusable"), wherein after the contents of carpule have been poured out, the carpule can be replaced and the injection device with the new carpule can be reused. In contrast, however, disposable injection devices, which are also referred to as "bimers", are discarded after the last pourable dose at the latest after one or more injection procedures. Carpule cannot be replaced in such disposable injection devices.

The injection device comprises a housing within which the dose and expelling mechanism and also the return mechanism are located.

In this specification, the term "distal end" refers to the face or direction facing the front insertion side end of the injection device or facing the tip of the injection needle. In contrast, the data "proximal" refers to the face or direction facing the end of the injection device opposite the end of the posterior insertion face.

The conceptual axial direction relates to the longitudinal axis of the housing. Correspondingly, the axial direction is parallel to the longitudinal axis of the housing or in the longitudinal direction of the housing. Longitudinal direction refers to a direction at right angles to the longitudinal axis of the housing.

The concepts "product", "drug" or "medical substance" in this specification include any flowable formulation suitable for controlled administration in subcutaneous or intramuscular tissue by means of a cannula or hollow needle, such as a liquid, solution, gel or fine suspension, containing one or more medical substances. That is, the medication may be one component with a single substance or a component with multiple substances premixed or co-formulated from a single container. This concept includes, in particular, drugs like peptides (e.g. insulin, insulin-containing drugs, GLP 1-containing and derived or similar formulations), proteins and hormones, biologically extracted or active substances, hormone-or gene-based substances, nutritional formulations, enzymes and other substances, whether in solid (suspended) or liquid form. The concept furthermore also includes polysaccharides, vaccines, DNS or RNS or oligonucleotides, antibodies or parts of antibodies as well as suitable base, auxiliary and carrier materials.

The concept "injection device" or "syringe" in this specification refers to a device in which an injection needle is removed from tissue after completion of the expelling of a controlled amount of a medical substance. The difference between an injection system or a syringe and an infusion system is therefore that the injection needle does not remain in the tissue for a longer period of several hours.

The concept "torsion-resistant" means that there may be no relative rotational movement. Thus, for example, according to the invention, the third coupling element is connected to the plunger rod in a rotationally fixed manner. This means that the third coupling member is not rotatable relative to the plunger rod. The term "rotationally coupled or decoupled" means that, in the rotationally coupled state, no relative rotational movement is possible. In the rotationally uncoupled state, relative rotational movement between the two components is possible.

In a preferred embodiment, the cam mechanism is formed by a guide slot in one of the first or second coupling members and a guide projection on the other of the first or second coupling members. The guide projection is guided by the guide slot, whereby a rotational movement of the first coupling member can be converted into a linear and axial displacement of the second coupling member relative to the housing. Preferably the second coupling member is only axially displaceable and not rotatable.

Preferably, an axial displacement of the second coupling member causes an axial displacement of the third coupling member relative to the plunger rod and also relative to the housing, whereby the third coupling member connects or disconnects the drive sleeve to the plunger rod. By means of the axial displacement, the third coupling part preferably engages with or disengages from the drive sleeve.

Since the third coupling member is always rotationally coupled to the plunger rod, the drive sleeve is rotationally coupled to the plunger rod if the third coupling member is connected to the drive sleeve. The drug delivery device is then in its coupled state ready for pouring out. If, on the contrary, the third coupling member is not connected to the drive sleeve, the drug delivery device is in a disengaged state in which the plunger rod can be returned (reset movement) by the user.

Preferably, the second and third coupling elements are not movably or fixedly connected to each other in the axial direction. This also forces the third coupling part to move axially when the second coupling part is moved axially.

The first, second and third coupling elements are preferably of tubular design. Preferably, the third coupling element is at least partially located inside the drive sleeve in the coupled state. This results in a space-saving arrangement.

Preferably, the first coupling member is configured as an operating sleeve which is selectively rotatably coupled to the kapur clamp. The second coupling part is preferably designed as a sleeve-like coupling ring, which is connected to the actuating sleeve by a cam mechanism. The third coupling element, which is connected to the plunger rod in a rotationally fixed but axially displaceable manner, is preferably moved axially distally or proximally by means of the coupling ring.

In a preferred embodiment, the first coupling part comprises a coupling part which can be brought into engagement with a corresponding coupling part in the cartridge holder for selective rotational coupling of the first coupling part to the cartridge holder. The engagement piece and the counter-engagement piece can be connected, for example, in the manner of a key-and-slot connection, so that a rotationally fixed connection is present.

Preferably, the first coupling part is mounted so as to be axially displaceable relative to the housing. The drug delivery device furthermore comprises a resilient element (e.g. a spring or a resilient plastic) by means of which the first coupling member can be pretensioned distally. Thereby ensuring that the carpule presses with pretension against a distal stop in the carpule clamp. The carpule is therefore immovably held in the carpule clamp by the elastic element and the coupling. Different lengths of kapur (due to machining tolerances) can also be compensated for by the resilient element.

In a preferred embodiment, the drug delivery device comprises a ratchet element with a ratchet arm, which is configured to co-act with a counter element, such as e.g. teeth or protrusions on the housing. The ratchet element thereby allows rotation of the drive sleeve in a first rotational direction (the cocking direction) relative to the housing and prevents rotation of the drive sleeve in a second rotational direction (the dose direction) relative to the housing.

Preferably the ratchet element is formed as a single separate component. That is, the ratchet element is not integrally formed with the housing or other element. This simplifies the manufacture of the ratchet element. The ratchet element is preferably held in a rotationally fixed manner on the housing, for example by means of a form-fit or by a snap-in connection.

Preferably the ratchet element is substantially made of a metallic material. The ratchet element can thus be produced from sheet metal, for example as a stamped part and a bent part.

Drawings

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. These embodiments are intended to represent the principle feasibility of the invention and are absolutely not designed in a limiting manner. Wherein:

fig. 1 shows in an exploded view a drug delivery device according to the invention in the form of an injection pen;

FIG. 2 shows a perspective view of a drive sleeve of an injection pen;

FIG. 3a shows a side view of the operating sleeve of the injection pen;

FIG. 3b shows a perspective view of the operating sleeve of FIG. 3 a;

fig. 4a shows a cross-sectional view of an injection pen, wherein the cross-sections are distributed through the longitudinal axis;

FIG. 4b shows an enlarged view of the proximal region of the injection pen of FIG. 4 a;

FIG. 5 shows the injection pen after adjustment of the dose;

figure 6 shows the injection pen after pouring out the dose;

FIG. 7 shows the housing without the kapur clamp and with kapur disengaged;

FIG. 8 shows the injection pen in an engaged state;

FIG. 9 shows a perspective exterior view of an injection pen with a protective cover;

fig. 10 shows an external view without the protective cover;

FIG. 11 shows another external view;

fig. 12 shows an external view of the proximal region of the injection pen.

Detailed Description

Fig. 1 shows an exploded view of a medication delivery device according to the invention in the form of an injection pen. For this description, the end of the insertion surface of the injection pen 1 is disclosed as the distal end and the end of the injection pen 1 opposite the end of the insertion surface is disclosed as the proximal end. Accordingly, the direction toward the needle or insertion direction is referred to as the distal direction, and the direction away from the needle is referred to as the proximal direction. Thus, in fig. 1, the distal end of the insertion side of the injection pen 1 is in the lower left area and the proximal end of the injection pen 1 is in the upper right area.

In the embodiment shown, the injection pen 1 is designed as a reusable (reusable) injection pen 1. As can be seen in fig. 1, the injection pen 1 comprises: a removable protective cap 5, an elongated cylindrical housing 10, a dosing and pouring mechanism inside the housing, and a carpule holder 13 containing a carpule 6 with a medical substance therein.

Dosing and pouring mechanism

The dosing and dumping mechanism of the injection pen 1 is described in detail below. The resetting mechanism for replacing the carpule is described later.

In the description of the dose and pouring mechanism, reference is first made to the structural features of the individual components. The function, in particular the adjustment, correction and decanting of the dose, is explained hereinafter.

Inside the housing 10, the injection pen 1 comprises a housing fixed housing sleeve 15, a dose sleeve 20 for adjusting and correcting a dose, a display sleeve 28, a coupling sleeve 30, a drive sleeve 40, and a plunger rod 60 arranged inside the drive sleeve 40, which plunger rod can be driven through the drive sleeve 40 to expel a medical substance from the carpule 6. The injection pen 1 furthermore comprises a pouring button 70 on the proximal end for triggering the pouring process.

The cartridge 13 can be releasably connected to the housing 10 in the distal end region of the housing 10 by means of a bayonet connection. The carpule holder 13 stores the carpule 6 and has an injection needle on its distal end or an injection channel (not shown) may be provided.

Furthermore, the carpule clamp 13 has two projections 14 in the proximal end region, so that the carpule clamp 13 is connected to the housing 10. For this purpose, two engagement elements in the form of recesses 15 are present in the proximal end region for the rotational coupling with the actuating sleeve 90.

The housing 10 is formed in a sleeve shape. In the proximal region, the circumferential surface of the housing sleeve forms a radial indentation or opening 11. The numerical scale on the display sleeve 28 can be seen from the outside through this opening 11.

The inner housing sleeve 15 has a cylindrical shape and is arranged coaxially with the housing sleeve outside the housing 10. By means of a snap-action switch which engages in a wall on the inside of the housing 10, the inner housing sleeve 15 is snapped onto the housing 10 both axially and rotationally fixed thereto.

For this purpose, the housing sleeve 15 has, in its inner proximal region, a thread element 16 which engages in a thread with an external thread 22 of the dose sleeve 20. In the proximal region, it also forms an axially oriented bridge (not shown). The screwing movement of the maximally adjustable single dose or dose sleeve 20 out of the housing sleeve 15 is limited by this bridge. The inner housing sleeve 15 thus rotatably stores the dose sleeve 20 relative to the housing 10.

The dose sleeve 20 has the shape of a hollow cylinder or sleeve and has a region with a diameter at the proximal closure which is larger than the rest of the dose sleeve 20 and serves as a handle 21 for rotating the dose sleeve 20. The handle 21 is not complementary to the housing 10 but is at the closure of the proximal end of the housing 10 as can be seen in fig. 4. On the proximal end of the handle 21, the handle has an inwardly circulating boss 26, also visible in fig. 2.

In the region of the handle, the dosing sleeve 20 has a larger inner diameter. At the transition from the smaller inner diameter to the larger inner diameter, the inner part of the dose sleeve 20 presents an annular surface at right angles to the longitudinal axis. On this face, circumferential axial teeth 25 are provided.

The dose sleeve 20 is, as mentioned, in a threaded connection with the inner housing sleeve 15. For this purpose, the dose sleeve 20 has an external thread 22 on its outer side. At the distal end of the external thread 22, the dose sleeve 20 comprises an axially oriented and radially projecting bridge as a stop element 23 which, in the proximal position of the dose sleeve 20, stops against an axial bridge of the inner housing sleeve 15.

The display sleeve 28 has a numerical scale on its outside to display the adjustable dose to the user. At the distal end, the display sleeve 28 has two circumferentially distributed recesses 29, into which the bridge 24 (fig. 4) of the dosing sleeve 20 engages, in order to rotationally fix the display sleeve 28 to the dosing sleeve 20. The display sleeve 28 is arranged outside the housing sleeve 15, while the dose sleeve 20 is inside the housing sleeve 15. Behind the proximal end of the housing sleeve 15, the sleeve 28 and the dosing sleeve 20 are shown to be interconnected with the above-mentioned recesses 29 and bridge tabs 24 in a rotationally fixed manner.

The hollow-cylindrical elongated coupling sleeve 30 has on its inner side a plurality of bridge-shaped webs 31 arranged circumferentially opposite the central elevation, as can be seen in fig. 1. For this purpose, the coupling sleeve 30 has a circumferential rim 32 in a proximal region, which rim has a distal and a proximal annular surface. On the distal face are four teeth 33 arranged opposite the axial direction via a circumferential distribution, which teeth, as described below, can co-act with the axial teeth 25 of the dose sleeve 20.

In a proximal region, the coupling sleeve 30 has a groove 34 on the inside for this purpose (see fig. 4). In this recess, a bridge 78 of the spring clip 76 can engage, so that the spring clip 76 is connected in a rotationally fixed manner to the coupling sleeve 30.

The spring clip 76 comprises a cylindrical section with a proximal side that does not pass through the hollow. The spring clip 76 includes a disc-shaped rim 77 on the proximal end. The cylindrical section is inside the coupling sleeve 30. A coupling spring 75 in the form of a metal compression spring is held between the distal end of the rim 77 of the spring clip 76 and the proximal end face of the rim 32 of the coupling sleeve 30.

The proximal end of the spring clip 76 is provided with the tilt button 70. The tilt button has an axial post 72 inside the sleeve-like section of the spring clip 76. The pouring button 70 furthermore comprises an annular flange 71 which is snapped in by means of the annular projection 26 of the dose sleeve 20. Whereby movement of the dump button 70 relative to the dose sleeve 20 is limited in the proximal direction. In the distal direction, the tilt-out button 70 rests with its legs 72 on the bottom of the hole of the spring clip 76. The pouring button 70, the coupling spring 75 and the spring clip 76 are thus axially movably held between the coupling sleeve 30 and the dosing sleeve 20.

The plunger rod 60 comprises an external thread 61 which is screwed into an internal thread 82 of a threaded joint 80 fixed to the housing (fig. 4). As can be seen in fig. 1, the plunger rod 60 has two recesses 62 offset by 180 ° in the tangential direction, which extend over the entire axial length of the plunger rod 60. The bridge 45 of the drive sleeve 40 engages in these recesses 62, so that the drive sleeve 40 is connected to the plunger rod 60 in a rotationally fixed but displaceable manner.

At the distal end of the plunger rod 60 is a button-like termination of the plunger rod 60 which may be snap-fit connected to a flange 63, whereby the flange 63 is rotatable relative to the plunger rod 60 but is axially fixedly held on the plunger rod 60. The flange 63 may act on a stopper in the carpule 6 in order to pour the medical substance out of the carpule 6.

Fig. 2 shows the drive sleeve 40 in an enlarged perspective view. The drive sleeve 40 is likewise cylindrical and has on its outer side an axial recess 41, which receives the bridge 31 of the coupling sleeve 30, so that the drive sleeve 40 and the coupling sleeve 30 are connected to one another in a rotationally fixed manner. At the distal end of the drive sleeve 40 is an endless rim 42. On its proximal annular face, serrations 43 are provided tangentially, which cooperate with ratchet arms 52 of the click spring 50, as described below.

In a distal end region, the drive sleeve 40 has on its inner side a plurality of radially inward webs 45 (visible in fig. 1) which can engage with the grooves 121 of the coupling element 120.

The coupling 120 has only a short axial length compared to the drive sleeve 40. On the outside, the coupling piece 120 has the just mentioned groove 121 and has an annular edge on the distal end. On the inside of one through-opening, radially inward webs 122 are present, which engage in the recesses 62 of the plunger rod 60. The coupling element 120 is thereby connected to the plunger rod 60 in a rotationally fixed manner at all times, but is supported on the plunger rod 60 so as to be axially displaceable.

The dosing and pouring mechanism furthermore comprises a click spring 50. The click spring is made as a metal stamped and bent piece and comprises a ring 51 on which two ratchet arms 52 are mounted, which project axially in the distal direction from the ring 51. The ratchet arms 52 are in this case formed elastically relative to the ring 51. The click spring 50 bears on a proximal face against a stop on the housing-fixed housing sleeve 15 and presses the ratchet arm 52 on a distal face into the serrations 43 of the drive sleeve 40. The click spring 50 is held on the housing 10 in a rotationally fixed manner by means of the saw-tooth-like recesses 54 on the ring 51. Since the click spring 50 is easily compressed, it is ensured that the ratchet arm 52 always engages with the serrations of the drive sleeve 40. The two ratchet arms 52 each have a curved end section 53 at their free end, which is intended to slide in the tilting direction via the serrations 43 in the event of a rotation of the drive sleeve 40 relative to the housing 10 in the tilting direction. In the reverse (adjustment direction), the curved end section 53 of the ratchet arm 52 pushes against the stop surface of the sawtooth 43, whereby rotation of the drive sleeve 40 relative to the housing 10 is prevented.

The function of the dosing and pouring mechanism is described in detail below.

In fig. 4, the injection pen 1 is shown in longitudinal section in the starting position. To adjust the dose, the dose sleeve 20 is rotated in the adjustment direction relative to the housing 10 on its handle 21 relative to the housing 10. Since the dose sleeve 20 is in threaded engagement with the inner housing sleeve 15, it is thereby screwed out of the housing sleeve 15. The display sleeve 28 is connected to the dose sleeve 20 in a rotationally fixed manner and therefore likewise rotates. The printed numerical indicia on the display sleeve 28 are visible through the opening 11 in the housing 10 and assist in adjusting the desired dosage.

Since the curved end section 53 of the ratchet arm 52 pushes against the stop surface of the sawtooth 43 of the drive sleeve 40, the coupling sleeve 30 is prevented from rotating in the adjustment direction by the drive sleeve 40 and the ratchet arm 52 of the click spring 50. Since the coupling sleeve 30 blocks the rotation in the adjustment direction, the plunger rod 60, which is connected to the coupling sleeve in a rotationally fixed manner via the coupling element 120, is also prevented from rotating in the adjustment direction.

In fig. 5, the injection pen 1 is shown in cross-section after adjustment of the dose. If an excessively high dose is accidentally adjusted, the dose can be corrected by re-screwing the dose sleeve 20 into the housing 10. The coupling sleeve 30 continues to rotate relative to the housing 10 because the friction force moving around the pre-tensioned ratchet arms 53 via the serrations 43 is greater than the friction force between the teeth 25 of the dose sleeve 30 and the teeth 33 of the coupling sleeve 30. Thus, when adjusting and correcting a dose, if the dose sleeve 30 is rotated in the adjustment or tilting direction (for correcting a dose), the coupling sleeve 30, the drive sleeve 40, the coupling member 120 and thus the plunger rod 60 cannot be rotated.

Because the dose sleeve 20 rotates relative to the coupling sleeve 30 when adjusting and correcting a dose, the axial teeth 25 of the dose sleeve 20 slide over the teeth 33 of the coupling sleeve 30 and thereby generate noise and vibration. Thus producing an audible and tactile return signal for the user in the adjustment direction (increasing the dose) and in the pouring direction (decreasing the dose).

Fig. 6 shows the injection pen 1 in a sectional view after the adjusted dose has been poured out. In order to pour out the adjusted dose. The user presses the dump button 70 in a distal direction. Whereby the coupling spring 75 is compressed and moves the coupling sleeve 30 axially in distal direction with respect to the dose sleeve 20 by means of the spring clip 76. By this movement, the teeth 33 of the coupling sleeve 30 come into engagement with the axial teeth 25 of the dose sleeve 20, whereby the coupling sleeve 30 is rotationally coupled to the dose sleeve 20.

If the user presses the lower tilt button 70, the dose sleeve 20 is swiveled into the housing 10 by the force of the distal action. This means that the friction between the ratchet arm 52 and the saw teeth 43 is overcome and the ratchet arm 52 slides through the saw teeth 43, whereby the coupling sleeve 30 can be rotated in the tilting out direction relative to the housing 10. This means that the coupling sleeve 30 is likewise rotated relative to the housing 10 by the rotating dose sleeve 20, which likewise rotates the drive plunger rod 60 via the coupling element 120. The plunger rod 60 is screwed in through the internal thread 82 on the screw joint 80, whereby the flange 63 on the distal end of the plunger rod 60 is axially moved in relation to the housing 10 and thus the plug in the carpule 6 is moved in the distal direction. The medical substance is thus poured out of the carpule 6.

As the coupling sleeve 30 is rotated in the tilting-out direction, the flexible ratchet arms 52 of the click spring 50 are moved by the saw teeth 43 of the coupling sleeve 30, thereby generating click noise and vibration,

resetting mechanism

The reset mechanism (reset mechanism) of the injection needle 1 will be described. This mechanism is used to reset the needle 1 when the full content of carpule 6 is poured out and the carpule 6 in the carpule holder 13 has to be replaced. First, the structural features are described. The function of the reset mechanism is described later.

Fig. 7 shows the injection needle 1 without the carpule holder, carpule, and shield in a cross-sectional view in a released state. In fig. 8, the injection needle 1 with the carpule clamp and carpule mounted in the coupled state is shown.

The reset mechanism includes a threaded nipple 80, an operating sleeve 90, a coupling ring 110 and a coupling member 120, all disposed within the interior of the housing 10. The operating sleeve 90, coupling ring 110 and coupling element 120 encircle the plunger rod 60.

The threaded joint 80 is held relative to the housing 10 by means of a snap-in connection. It is formed in the shape of a sleeve and has a bayonet guide 81 in the form of an elongated recess in its outer lateral surface (see fig. 1). The bayonet guide 81 serves to guide the projection 14 of the kapur clamp 13. As can be seen in fig. 7, the threaded joint 80 has an axial guide 83 on the inside in order to guide the coupling ring 110 axially and rotationally fixed. Further, the inside of the threaded joint 80 is provided with an operating sleeve 90, a kapur spring 85 and a coupling ring 110.

The coupling ring 110 is connected axially fixed to the coupling element 120 by means of a snap lock. Furthermore, the coupling ring 110 is supported axially displaceably inside the threaded joint 80 by means of the guide rail 83. The coupling ring 110 has on its outer side a radially outward guide cam 111 (visible in fig. 1). Furthermore, the coupling ring 110 is partly inside the operating sleeve 90.

The operating sleeve 90 is shown enlarged in fig. 3a and 3 b. It is cylindrical and rotatably supported inside the threaded joint 80. It has two coupling bosses 92 on its distal end which can be inserted into correspondingly shaped recesses in the kapur clamp 13 to rotationally connect the kapur clamp 13 with the operating sleeve 90. For this purpose, the actuating sleeve 90 has guide grooves 91 on its outer lateral surface. The guide cam 111 of the lead engaging ring 110 is guided in the guide groove 91. The guide groove 91 and the guide cam thus form a cam mechanism between the operating sleeve 90 and the coupling ring 110. The guide groove 91 has in this respect three

sections

93, 94, 95 which are connected to one another, as can be seen in fig. 3 a. In the first section 93, the guide groove 91 runs tangentially at right angles to the longitudinal axis of the injection needle 1. In the inclined second section 94, the guide grooves run obliquely, that is to say both tangentially and proximally (like a thread). In the third section 95, the guide grooves 91 are again distributed only in the tangential direction. The function of the cam mechanism with the guide groove 91 and the guide cam 111 will be described in further detail below.

The operating sleeve 90 is axially movably supported within the housing-fixed threaded joint 80. As can be seen in fig. 7, on the proximal side of the operating sleeve 90 is a coupling spring 85. The coupling spring is easily compressed and supported on the proximal side of the threaded joint 80 and on the distal side of the operating sleeve 90. The actuating sleeve 90 is thereby pretensioned in the distal direction against a distal stop in the threaded joint 80.

If the medical substance is completely poured out of the carpule 6, the carpule 6 in the injection pen 1 is replaced. For this purpose, the carpule holder 13 is rotated by a certain angle range relative to the housing 10 as a first step and then pulled out of the housing 10 in the distal direction by pulling. The cam 14 is thereby guided out of the bayonet guide 81 and releases the bayonet connection between the bayonet catch 13 and the housing 10. During the rotational movement of the carpule clamp 13, the operating sleeve 90, which is rotationally coupled with the carpule clamp 13, also rotates. Since the coupling ring 110 is guided axially in the housing sleeve 80 but cannot rotate, the operating sleeve rotates relative to the guide collar 110. Whereby the guide groove 91 moves relative to the guide cam 111. If limited by the inclination of the inclined section 94 of the guide groove 91, the guide cam 111 and thus the entire coupling ring 110 move axially in the distal direction relative to the housing 10. Since the coupling ring 110 is axially fixed in connection with the coupling member 120, the coupling member 120 is also moved with respect to the housing 10 and also with respect to the plunger rod 60 by axially moving the coupling member. As a result, the coupling 120 is pulled distally out of the drive sleeve 40. The rotational coupling between the drive sleeve 40 and the coupling sleeve 30 and thus also between the drive sleeve 40 and the plunger rod 60 is thereby cancelled. The plunger rod 60 is therefore free to rotate together with the coupling element 10. The plunger rod 60 is thus pushed back into the housing 10 in the proximal direction by the user's hand in order to reset the needle 1 and prepare it for a new injection. At the same time, the plunger rod 60 is screwed in the proximal direction through the internal thread 82 in the nipple 80.

After the new carpule 6 has been inserted into the carpule holder 13, the carpule holder 13 is introduced with its proximal end region into the housing 10 or the distal end region of the threaded joint 80 in the distal direction. The cams 14 of the kapur clamp are at the same time accommodated in the bayonet guides 81 of the screw joint 80. By axially inserting the proximal end region of the kapur grip 13 into the housing 10, the recess of the kapur grip 13 engages with the coupling projection 92 on the distal end of the actuating sleeve 90. The carpule clamp 13 and the operating sleeve 90 are thereby rotationally coupled to each other.

To connect the bayonet catch 13 completely to the housing 10, the bayonet catch 13 must then be moved in an axial movement in a rotational movement relative to the housing 10 (bayonet connection). Upon this rotational movement, the operating sleeve 90 also rotates relative to the housing 10. Whereas the coupling ring 110 is held rotationally fixed relative to the housing 10 by the threaded joint 80. The threaded joints are therefore not able to rotate simultaneously. This relative rotation between the operating sleeve 90 and the coupling ring 110 causes the guide groove 91 to move relative to the guide cam 111. By means of the inclined section 94 of the guide groove 91, the guide cam 111 and thus the entire coupling ring 110 is pressed axially fixedly in the proximal direction (due to the cam mechanism). Since the coupling element 120 is axially fixedly connected with the coupling ring 110, the coupling element is also moved in the proximal direction with respect to the housing 10 and also with respect to the plunger rod 60. The recess 121 of the coupling element 120 thus engages with the bridge 45 of the drive sleeve 40. This means that the coupling 120 is moved into and rotationally coupled with the drive sleeve 40. The drive sleeve 40 is thereby connected in a rotationally fixed manner to the plunger rod 60 via the coupling element 120, which is connected in a rotationally fixed manner to the plunger rod 60 at all times. Rotation of the drive sleeve 40 in this engaged state thus causes rotation of the plunger rod 60. The injection pen 1 is now again in the engaged state.

By means of the compressed kapur spring 85, which pretensions the operating sleeve 90 distally, the spring force acts in the distal direction on the kapur 6. The kapur 6 is thus pre-tensioned in the kapur gripper 13 and is held immovably.

All components except the coupling spring 75, the carpule spring 85 and the carpule are made of plastic, preferably polypropylene. The coupling spring and the kapur spring are made of spring steel.

In fig. 9-12, an injection pen 1 according to the invention is shown in a perspective appearance. In fig. 9, the injection pen 1 is shown with the protective cap 5 attached. In this figure, the housing 10 can furthermore be seen, as can the opening 11 in the housing 10, through which the numerical scale of the display sleeve 28, the handle 21 of the dose sleeve 20 and the pouring button 70 can be seen.

Fig. 10 shows the injection pen 1 without the protective cover 5. In this figure it can be seen that on the distal end of the carpule clamp 13 there is a needle guard 7, which protects the injection needle (not shown) and has to be removed before the injection. In addition, the peg 8 on the proximal end of the kapur clamp 13 can be seen. When the protective cap 5 is mounted, the pegs 8 engage in correspondingly shaped recesses on the inside of the protective cap 5. The protective cap 5 is thereby held in the housing 10 or the bayonet catch 13 by means of the bayonet connection in a defined rotational direction. A portion of the carpule 6 is visible through an elongated axial void in the carpule holder 13.

Fig. 11 shows another perspective appearance of the injection pen 1 from the side opposite to the side shown in fig. 10. In other words, fig. 11 rotates the injection pen 1 of fig. 10 around its longitudinal axis by 180 °.

Fig. 12 shows the proximal region of the injection pen 1, wherein the viewing directions are distributed from the proximal end to the distal end. In this figure it can be seen that the company logo 9 or company logo of the manufacturer of the injection pen 1 is formed by a recess in the proximal terminal face of the tilt button 70.

Claims

1. A drug delivery device (1) for pouring a dose of a product from a carpule (6) contained within the drug delivery device (1), the drug delivery device (1) comprising:

a housing (10) defining an axial direction;

a kapur clamp (13) releasably connected to the housing (10);

a plunger rod (60);

a drive sleeve (40) for driving the plunger rod (60);

a first coupling member (90) rotatable relative to the housing (10);

a second coupling member (110) axially movable relative to the housing (10);

a third coupling element (120) which is connected to the plunger rod (60) in a rotationally fixed manner and is axially movable relative to the plunger rod (60) and the housing (10),

wherein the carpule clamp (13) is connectable to or disconnectable from the housing (10) by at least one rotational movement relative to the housing (10), wherein the first coupling (90) is rotated by the rotational movement,

it is characterized in that the preparation method is characterized in that,

the first coupling member (90) and the second coupling member (110) being coupled to each other by a cam mechanism such that rotation of the first coupling member (90) causes axial movement of the second coupling member (110),

wherein the third coupling member (120) is rotationally coupled to or decoupled from the drive sleeve (40) by the axial movement.

2. The drug delivery device (1) according to claim 1, wherein the cam mechanism is formed by a guide slot (91) in one of the first coupling member (90) and the second coupling member (110) and by a guide projection (90, 111) on the other of the first coupling member (90) and the second coupling member (110).

3. The drug delivery device (1) according to claim 1 or 2, wherein said axial movement of said second coupling member (110) causes an axial movement of said third coupling member (120) relative to said plunger rod (60), whereby said third coupling member (120) is rotationally coupled to or decoupled from said drive sleeve (40).

4. The drug delivery device (1) according to claim 1, characterized in that the second coupling element (110) and the third coupling element (120) are connected to each other in an axially immovable manner.

5. The drug delivery device (1) according to claim 1, characterized in that the first coupling element (90), the second coupling element (110) and the third coupling element (120) are formed as a sleeve.

6. The drug delivery device (1) according to claim 1, characterized in that the first coupling member (90) comprises an engagement member (92) which can be engaged in a corresponding engagement member in the cartridge holder (13) for rotational coupling of the first coupling member (90) to the cartridge holder (13).

7. The drug delivery device (1) as claimed in claim 1, characterized in that the first coupling member (90) is furthermore axially displaceably supported relative to the housing (10) and in that the drug delivery device (1) has an elastic element (85) by means of which the first coupling member (90) can be pretensioned in the distal direction.

8. The drug delivery device (1) according to claim 1, characterized by a ratchet element (50) having a ratchet arm (52) which is configured to co-act with a counter-piece (43) to effect rotation of the drive sleeve (40) relative to the housing (10) in a first rotational direction and to prevent rotation in a second rotational direction opposite to the first rotational direction.

9. The drug delivery device (1) according to claim 8, characterized in that the ratchet element (50) is constructed as a separate component.

10. The drug delivery device (1) according to claim 8, characterized in that the ratchet element (50) is held on the housing (10) in a rotationally fixed manner.

11. The drug delivery device (1) according to claim 9 or 10, characterized in that the ratchet element (50) is made of a metallic material.