CH711379A2 - Injection device. - Google Patents

Abstract

The invention relates to injection devices for administering a fluid medicament substance having an elongate housing (106) with a fixed insert (110) and a longitudinal axis L, a holder for a medicament substance container (5) attached to the distal end of the housing (06), an energy store a sleeve-shaped mechanism holder (107), a metering member (113), wherein the metering member (113) for setting a dose about the axis L relative to the housing (106) can be rotated, a push button (112), wherein the push button through the by the dosing element extending region with the mechanism holder is secured against rotation and slidably connected, a sleeve-shaped display element (108), and an elongated output device (109), in particular a piston rod. Furthermore, the injection device comprises a first clutch with which the push button (112) and the display element (108) can be coupled in a rotationally fixed manner, a second clutch with which the push button (112) and the housing (106) can be coupled in a rotationally fixed manner to a transmission device for operatively coupling the indicator member (108) to the output device (109) such that rotation of the indicator member (108) relative to the mechanism holder (107) results in axial displacement of the output member relative to the mechanism holder (107) and vice versa. The couplings are actuated by an axial displacement of the push button. When setting and correcting a dose, the first clutch is closed, the second clutch is opened, and the dose is adjusted by rotating the dosing button (113). To administer the adjusted dose, the pushbutton (112) is moved distally, thereby first closing the second clutch and then opening the first clutch. During administration, the energy store operatively acts on the display element (108), rotating it and causing the transfer device to axially displace the output device (109).

Description

Technical area

The invention relates to injection devices, in particular injection pens, with which a fluid product contained in a product container, in particular in multiple and variable doses, can be automatically poured out. The fluid product is in particular a drug. In particular, the invention relates to an injection device which can be adapted cost-effectively to different drugs and drug concentrations.

background

An injection device, such as an injection pen, in which the force required to administer medication is at least partially applied by an energy source stored in the injection pen, can in principle be suitable for the administration of a wide variety of medications, provided the medication has a consistency has, which can be poured out with the injection device.

The term "medicament" as used herein encompasses any flowable medicinal formulation which is suitable for controlled administration by an agent such as e.g. a cannula or hollow needle, for example comprising a liquid, a solution, a gel or a fine suspension which contains one or more medicinal substances. “Medicinal product” can be a composition with a single active ingredient or a premixed or co-formulated composition with several active ingredients from a single container. Medicines include drugs such as peptides (e.g. insulins, drugs containing insulin, preparations containing GLP-1 as well as derived or analogous preparations), proteins and hormones, biologically obtained or active substances, substances based on hormones or genes, nutritional formulations, enzymes and other substances both in solid (suspended) or liquid form but also polysaccharides, vaccines, DNA or RNA or oligonucleotides, antibodies or parts of antibodies as well as suitable basic, auxiliary and carrier substances.

From WO 2009/105 909 an automatic injection pen is known, in which a spiral spring is arranged, which provides the energy required for dispensing medicaments. The coil spring is tensioned when a dose is set, which means that the person using it has to tension the spring mechanically for each dose.

From US 8 608 708 an injection device is known in which a pretensioned torsion spring as a drive spring provides the energy for the administration of the doses. Pre-tensioned in this case means that the torsion spring stores enough energy through the pre-tensioning to pour out the entire contents of the carpule shown. As a result, the user does not have to apply any force when setting the dose in order to tension the drive spring.

From WO 2014/170 267 a drug administration device is known in which several series-connected, pretensioned springs provide the energy for the administration of the doses.

From EP 2 881 131 A1 a drive and metering device for an injection device is known in which a drive spring, which is pretensioned between a dose setting member and a drive member, provides the energy for administering the doses.

For manufacturers of injection devices, drug manufacturers, health insurers and people to be cared for, there is a need to have injection devices on hand that are as inexpensive as possible, but safe and effective.

task

It is an object of the invention to provide an alternative injection device which can be inexpensively adapted to different drugs and drug concentrations.

Solution and general description

[0010] The object is achieved according to the invention by independent claim 1; advantageous further developments result from the dependent claims, the description and the figures.

The injection device according to the invention has an elongated housing, in particular in the form of an elongated cylinder, and a product container arranged in the housing. The product container is preferably a prefilled syringe or a carpule. The product container can be fixedly arranged in the housing; in particular, the product container can be held on the injection device by a carpule holder or syringe holder. The injection device further comprises a dispensing mechanism, which can preferably cause the product to be dispensed by an energy store arranged in or on the injection device, such as a spring, a battery, a gas pressure container, a gas generator or an osmotic drive device. In the event that the product container is a carpule, the injection device further comprises an injection needle which can be detachably attached to the housing and which creates a fluid path between the carpule contents and the injection tip of the injection needle. If the product container is a pre-filled syringe with a permanently attached injection needle, no separate injection needle is required.

In a further aspect, the injection device further comprises a metering device which enables the setting of a certain partial amount or dose of the product present in the product container, the set dose then being poured out with the dispensing mechanism. The dosing device and dispensing mechanism can be designed in such a way that precisely one dose can be dispensed or that several doses of variable sizes can be dispensed one after the other from the same product container. In a further aspect, several cans of the same size can be poured out by means of the pouring mechanism.

In a further aspect, the injection device can be intended for single use, so that the device must be disposed of after the product container has been emptied. In further refinements, the product container can be exchanged and the injection device can thus be designed to be reusable. Alternatively, parts of the injection device can be exchangeable together with the product container, so that a so-called semi-disposable system is created.

In the event that the injection device is intended for single use, the energy store can also be discharged or emptied after the product container has been emptied. In the case of an exchangeable product container and reusable injection devices, the energy store can be designed to be rechargeable, refillable or exchangeable. Alternatively, the energy store can also contain energy for emptying several product containers.

In a further aspect, the injection device can comprise a needle protection sleeve which covers the injection needle. In a preferred form, the needle protection sleeve for injecting product can be moved in one direction, so that it releases the injection needle for the injection. In a further preferred form, after the injection, the needle protection sleeve moves again over the injection needle and is firmly locked relative to the housing, so that no further, in particular unwanted, lancing processes are possible.

In a further aspect, the injection device can comprise a pull-off cap which covers that end of the injection device which houses the injection needle. The pull-off cap can protect the injection device from unintentional triggering before the planned use or protect the needle protection sleeve from unwanted manipulation, for example during transport or the unpacking process. In a further aspect, the pull-off cap can be used to remove any needle protection cap from the injection device before use, as is customary for prefabricated syringes, for example, in order to keep the needle sterile in particular.

The housing of the injection device is preferably elongated and forms the longitudinal axis of the injection device. The housing is preferably sleeve-shaped and / or cylindrical, in particular circular cylindrical. At the proximal end of the housing, a dosing button is arranged coaxially to the housing, which can be rotated relative to the housing to set or correct a dose, but is axially fixed. The dosing button is preferably approximately ring-shaped, the central axis of the ring being arranged coaxially to the longitudinal axis of the injection device. The dosing button is open in the proximal direction. A push button is arranged in this opening, which is secured against rotation with respect to the dosing button, but has, in particular, limited displaceability in the axial direction.

Arranged in the housing is a housing insert which is axially and rotationally fixed in the housing. In a preferred embodiment, this insert is approximately disk-shaped and has an opening in the middle, so that a ring results. Radial stops for the pen mechanism can be arranged on its periphery. A sleeve-shaped mechanism holder aligned coaxially with the housing is rotatably arranged on the insert and is axially fixed. At its distal end, the mechanism holder has an opening into which an elongated output member can be inserted. The output member is axially displaceable and secured against rotation in the mechanism holder. The output member can be designed as a classic piston rod, but can also be sleeve-shaped. The anti-twist device and longitudinal guidance between the mechanism holder and the output member can take place via a tongue / groove connection or alternatively also through an internal shape of the mechanism holder that is not circular in cross-section or the external shape of the output member. Alternatively, the longitudinal guide can also be designed as a very steep threaded connection, so that the longitudinal guide contains a rotational component, with an anti-twist device still in place at each individual point in time. The distal end of the output member is used to act on the stopper or plunger of the carpule or pre-filled syringe with an axial force, in particular with low torque, in order to expel medicament from the medicament container.

On the outside of the mechanism holder, but inside the housing, a display device is axially fixed and rotatable. The nature of the device means that the display device is designed in the shape of a sleeve or ring. A dose scale is arranged on the outer surface of the display device. At least two, in particular radial, stops are arranged on the periphery of the display device. Alternatively, it can also be a two-sided stop. The angle swept around the longitudinal axis of the injection device between the at least two stops gives the possible span for a dose, as the range between a zero position and the maximum dose that can be set. Due to the construction, the swept angle is <360 °. The display device is arranged so that the stops of the display device with complementary stops on the housing insert or, alternatively, on other parts of the housing at the zero position, respectively. the position of the maximum dose interact and thereby a movement of the display device below the zero position, respectively. is mechanically prevented beyond the position of the maximum dose. These complementary stops potentially further restrict the possible angle 0 to be covered (0 °>> 360 °). The stops are dimensioned so that they can permanently withstand a force (or torque) that is generated by energy from the energy store.

In alternative configurations of the display device, this is configured in several parts, in particular in two parts. In the two-part form, the dose scale is designed as a separate display drum compared to the above example, which is guided axially displaceably on the display device. On the outside of the display drum, threaded elements are arranged which are in engagement with an internal thread of the housing. If the display device is now rotated relative to the housing, for example to set a dose, the display drum performs a helical movement. Correspondingly, the dose scale on the display drum is also arranged in the form of a helix on the drum. Basically, this allows the attachment of more legible scale information.

In a further advantageous embodiment, the multi-part display device can also be designed so that angles of more than 360 ° can be swept over between the zero position and the maximum adjustable dose. As described above, the display device is then designed in several parts, in particular in two parts. The dose scale is designed as a separate display drum, which is axially displaceable but non-rotatably guided on the sleeve-shaped or ring-shaped display device. On the outside of the display drum, threaded elements are arranged which are in engagement with an internal thread of the housing. As described above, the indicator drum performs a helical movement when setting the dose. In the present embodiment, the stops for the zero position and the maximum adjustable dose are arranged on the display drum. The stop for the zero position is a radial stop at the distal end of the display drum and the stop for the maximum dose is at the proximal end of the display drum. As a result, at least the complementary stop for the maximum adjustable dose has to be shifted in the proximal direction compared to the previous embodiments, since the dose limitation no longer limits a rotary movement of the display device, but rather limits the helical movement of the display drum. For this purpose, the stop can be arranged on the housing or a part close to the housing. By introducing the axial component on the display device (the display drum), the possible angle that can be swept over when setting a dose can be expanded to> 360 °. In this way, for example, the dose labeling applied to the display drum can be made more legible, in particular larger.

In one aspect of the invention, the display device is operatively connected to the output member via a transmission unit. In particular so that a rotation of the display device relative to the mechanism holder causes a displacement of the output member relative to the mechanism holder. In a simple embodiment according to the invention, the transmission unit is designed as a threaded connection between the output member and the display device. The thread pitch determines how much the output member moves axially relative to the mechanism holder when the display device is rotated through a predetermined angle.

In a further possible embodiment, the transmission unit consists of a transmission. At least one gearwheel is rotatably attached in the distal area of the mechanism holder, which can rotate about an axis approximately perpendicular to the longitudinal axis of the injection device (slight deviations from the perpendicular can make sense for structural reasons). The gear is designed in such a way that it has two partial gearwheels with different diameters and / or different numbers of teeth. Alternatively, two gears can be arranged one behind the other and firmly connected to one another via a central axis of rotation. A sub gear, the input gear, receives relative rotation of the display device. For this purpose, a toothed ring is arranged on the display device, which meshes with the teeth of the input gear. If the display device rotates relative to the mechanism holder, the input gear is set in rotation, as a result of which the second sub-gear, the output gear, is also rotated. Due to the arrangement of the gear on the mechanism holder, the second partial gear can transfer the movement to the output member, the rotation of the output gear being converted into a linear axial movement of the output member. For this purpose, axially extending teeth are arranged on the output member, similar to a toothed rack, which meshes with the teeth of the output gear. By suitable selection of the diameter of the input and output gearwheels, the movement transmitted from the display device to the output member can be increased or decreased. In one embodiment, the gears have radially aligned teeth. The orientation can, however, also be different, for example bevel gears can also be used as input and / or output gears.

In a further advantageous embodiment, the transmission unit is designed as a ball screw drive. The display device comprises the nut element and the output member the spindle element. The thread connection between the display device and the output member is made by balls which circulate in the closed circuit of the ball screw drive. Such ball screw drives are known to the person skilled in the art from US Pat. No. 3,156,236, for example.

In a further embodiment, the transmission unit can comprise an electric motor, in particular a piezo, ultrasonic or traveling wave motor, which is arranged coaxially with the output member. The stator of the electric motor is fixed to the housing and the rotor is threadedly connected to the output member, a rotation of the rotor enabling an axial movement of the output member. This embodiment requires at least one electrical energy store, which supplies the motor with energy.

The described variants of the transmission units enable simple adaptation to different drugs or drug concentrations by changing the transmission units, with which the gear ratios can be changed.

The envisaged energy store is a mechanical spring in preferred forms. This can be a compression spring or a torsion spring, a spiral or clock spring as well as a combined tension / compression spring would also be possible. If a torsion spring is used, the spring can be arranged kinematically between the dosing button and the display device and, before the first use, be preloaded with enough energy that at least the entire contents of the medication container can be administered with it. If a compression spring is used, the compression spring can be arranged between the output member and the mechanism holder. After assembly, the compression spring has enough energy applied to it so that the entire medication container can be administered. If, as described above, the injection device comprises an electric motor in the transmission unit, the injection device needs an energy store for electrical energy at least for the electric motor. In parallel with this, the actual drive of the output member can continue to function via a spring described above. Alternatively, however, it is also possible and at most advantageous that the energy for the movement of the output member is also provided by the electric motor.

In one aspect, the dosing or push button are secured against rotation with respect to the mechanism holder, for example by at least one suitable longitudinal guide.

According to a further aspect of the invention, the injection device comprises various releasable couplings. A coupling can be arranged between the push button and the housing of the injection device. If the clutch is closed, the push button and all other elements, which are secured against rotation with respect to the push button, cannot rotate relative to the housing. Another coupling can be arranged between the display device and the push button. If this coupling is opened, the push button and all other elements, which are secured against rotation with respect to the push button, can rotate relative to the display device. When the injection device is in the idle state, a coupling spring (or coupling spring elements) arranged in the injection device can act so that the coupling between the push button and the housing is opened and any coupling between the push button and the display device is closed.

The housing of the injection device has an opening or a window on its lateral surface. The currently set dose, which is arranged on the outer surface of the display device, is visible through this opening.

The function of a general embodiment according to the invention will be briefly explained below. In this example, an injection device in the form of an injection pen is described, which allows the administration of several doses of a medicament of variable sizes. In this example there is a coupling between the push button and the housing as well as a coupling between the push button and the display device. The former is open in the idle state and when setting and correcting a dose, while the latter is closed. The injection device of this example further comprises a compression spring as an energy store. The compression spring is clamped between the mechanism holder and the output member. For this purpose, the output member is designed in the shape of a pot, as a sleeve which is closed distally and is open proximally. The spring is dimensioned so that it can be pushed into the output member. The distal end of the output member correspondingly supports one end of the spring. The other end of the spring is supported on the proximal end of the mechanism holder. If the output member is now pushed into the mechanism holder when the injection device is being assembled, the spring is tensioned and subsequently stores enough energy to be able to pour out the entire contents of the medication container. In this embodiment, the transmission unit is designed as a non-self-locking thread between the display device and the output member.

To set a dose to be administered, the dose button is rotated about the longitudinal axis of the injection device relative to the housing. The push button, the mechanism holder, the output element, the display device and the transmission unit rotate with the dosing button due to the various anti-twist devices. The set dose is then visible through the corresponding opening in the housing. If the dose is set too high by mistake, it can be corrected by simply turning back the dose button. As a result of the rotation of the display device, the display device has moved away from its zero position. The dose knob can be rotated until the radial stop for the maximum dose of the display device engages the complementary stop of the housing insert or the housing. Since the coupling between the push button and the display device is closed and the push button is in turn secured against rotation with respect to the dosing button, turning the dosing button beyond the maximum dose is prevented. The same applies to the zero position. Since the energy store already contains the energy required to administer a dose, the dosing movement does not involve any accumulation of energy. For example, in the case of a torsion or compression spring as an energy store, the relative position of the spring ends or the spring fastening elements to one another remains unchanged during the metering movement. Once the dose has been set, the push button is pressed, whereby the coupling between the push button and the housing is first closed and then the coupling between the push button and the display device is opened. As a result, the output member, mechanism holder, dosing button and push button are secured against rotation with respect to the housing. In contrast, in this state, the display device can be rotated relative to the housing and other elements. As mentioned, the compression spring is stretched between the output member and the mechanism holder. As a result, a force acts on the output member in the distal direction. The output member is mounted axially displaceably in the mechanism holder and connected to the display device via a thread. As long as the coupling between the push button and the display device is closed, an axial movement of the output member is not possible. If the coupling is opened, the display can rotate relative to the mechanism holder, the range of motion being limited by the radial stops in particular. Due to the threaded connection between the display device and the output member, the axial force of the compression spring acts on the display device via the thread. Since the thread is not designed to be self-locking, the force causes the display device to rotate and the output member moves in the distal direction. The pitch of the thread determines by how much the output member is displaced in the distal direction per dose unit displayed. When the display device reaches the zero position again, the particular radial stop of the display device for the zero position and the stop of the housing insert or the housing, which is designed to be complementary thereto, come into engagement with one another. This prevents any further rotation of the display device. As a result, the output link also stops. In a final step, the coupling between the display device and the push button is closed again, so that the display device is secured against rotation relative to the push button, and the coupling between the push button and the housing is opened. The injection device is thus again in a state in which a further dose can be set.

[0033] The embodiment described can be adapted relatively easily to different drugs and different drug concentrations. As mentioned, the transmission unit determines how much the output member shifts when the display device is rotated through a certain angle. In order to adapt the injection device to a different medicament or a different concentration in the described embodiment, only two parts have to be exchanged with the medicament container having the same design. The display device must be adapted with regard to the scale. The transmission unit has to be adapted to the new scale, which means that the thread pitch of the thread between the output member and the display device has to be adapted to the new scale.

The transmission device of the embodiment described, designed as a simple threaded connection in conjunction with a simple compression spring, can be further abstracted without departing from the spirit of the invention. The threaded connection between the output member and the display device is not self-locking in the embodiment described, which means that as soon as the coupling between the push button and the display device is released, the axial force that acts on the output member from the compression spring is sufficient to allow a relative movement between the display device and the output member to induce. The movement is limited by the stops for the zero position. In general terms, the task of the transfer device is to allow the pouring out movement within set limits. If the transmission device comprises a threaded connection between the display device and the output member, this threaded connection can be designed to be self-locking or, as described above, not self-locking, the boundary between self-locking and non-self-locking at a certain thread pitch being determined by the coefficient of static friction. If the tangent of the helix angle is smaller than the coefficient of static friction in the thread, then there is self-locking.

In the embodiment described, there is no self-locking. This means that the distribution movement must be blocked by appropriate means if no distribution is to be made. In the embodiment described, this is done by the combination of the coupling between the display device and the push button and by the radial stops at the zero position. Instead of a simple anti-twist device that can be coupled between the push button and the display device, in more general terms, a brake could also be used, which would be released selectively for a dose to be administered when the injection device was triggered. This could be a disc brake, for example, which is closed in the idle state and prevents distribution due to static friction in the brake. A magnetic or electromagnetic brake could also be used. An electrostatic system could also be used. Chemical or biochemical coatings could also be used in the brake, which change their properties, for example due to an applied electric field, and thereby release or block the brake.

Alternatively, if there is self-locking, this must be overcome in order to enable distribution. For this purpose, a supplementary torque will be applied. For example, an electric motor can be used for this purpose, which is preferably arranged coaxially with the output member. Due to the fact that the compression spring provides the actual propulsive force for the output member, the electric motor only has to provide enough torque that the frictional force in the threaded connection will be overcome. The electric motor is preferably a traveling wave motor, but normal DC motors, brushless DC motors, stepper motors or the like could also be used.

In a further aspect, the injection device comprises at least one sensor device which can qualitatively and / or quantitatively detect rotation of parts of the injection device relative to the housing. In one embodiment, several pulse generators can be arranged on the display device and at least one pulse sensor on the housing. In preferred variants, the pulse generators are arranged at regular intervals on the outer surface of the display device. The pulse sensor is arranged locally on the housing in such a way that the pulse generators are moved past the pulse sensor when the display device rotates relative to the housing and thereby trigger a pulse at the pulse sensor. The terms pulse generator and pulse sensor are to be interpreted broadly.

[0038] The pulse sensor can be one or more mechanical switches or buttons which are briefly actuated by pulse generators designed as elevations on the display device. The switches or buttons are connected to an electronic circuit which counts the actuation in particular. In one embodiment, the elevations can be arranged on the circumference of the display device, in particular at regular intervals and in the same axial position. The distances can then represent individual dosing steps, and it is thus possible to determine the set dose via the number of switching operations. The direction of rotation can also be deduced from the geometric shape and arrangement of the elevations.

In a further variant, a simple cylindrical surface of the display device represents the pulse generator. The pulse sensor is then designed as a wheel rotatably arranged on the housing, which rotates about an axis which runs parallel to the central axis of the injection device. The periphery of the wheel is in contact with the cylindrical surface and is driven by relative rotation between the housing and the display device. A sensor with associated electronics connected to the wheel determines the angle of rotation, the number of revolutions and the direction of rotation. The set dose can thus be determined via the rotation, including any correction of the dose.

The pulse generator can also be designed as a magnet and the pulse sensor as a magnetic sensor. Optical systems are also conceivable in which a light source illuminates the pulse generator, in particular designed as reflectors, depending on the position and the pulse sensor, designed as a light sensor with control electronics, picks up the light pulses depending on the relative position between light sensor and reflectors and converts them into an electrical signal, which is transmitted by the control electronics can be evaluated, from which the set dose can be determined.

In a further possible embodiment, the pulse generator is not arranged on the display device, but on the push button, the mechanism holder, the output member, or some other part that rotates relative to the housing when setting and correcting a dose, while the pulse sensor at most remains shifted in the axial direction on the housing. The possibility of arranging pulse generators on other parts that are not obvious at first glance lies in the nature of the injection device according to the invention, in which the dosing movement is taken along by most parts of the injection device. The pulse generator can be implemented on a suitable part by means of a coding in such a way that the pulse sensor can absolutely read off a possible current position of the part at any time without further ado. As an alternative or in addition, the coding is designed in such a way that the current position of the part can be determined relative to a reference position, for example by counting pulses.

The control electronics can include a display with which the specific dose can be displayed. Furthermore, the control electronics can include a memory in which information, in particular the dose history, can be stored. The control electronics can also include a communication module with which information, in particular the dose history and in particular to computers and smart phones, can be transmitted. Wireless connections via Bluetooth, NFC or WLAN can be used for this purpose, or the information can be transmitted in a wired manner via USB in particular. The control electronics can be arranged permanently on the injection device or, in a preferred variant, be accommodated in a module that can be detached from the injection device.

For the person skilled in the art, further embodiments and configurations are directly and obviously recognizable, which result from combinations of the examples described or combinations of the examples described with the general specialist knowledge of the person skilled in the art. The examples listed here and also below are intended to show basic possibilities of the invention and are in no way to be interpreted as restrictive.

characters

Fig. 1: Perspective view of a first embodiment Fig. 2: Exploded view of the first embodiment Fig. 3a: Top view of the distal end of the first embodiment Fig. 3b: Longitudinal section AA through the first embodiment in the initial state Fig. 3c: Longitudinal section BB through the first embodiment in the initial state Fig. 4a: Top view of the distal end of the first embodiment Fig. 4b: Longitudinal section E-E through the first embodiment at the end of the last of the emptying of the medication container Fig. 4c: Longitudinal section F-F through the first embodiment at the end of the last of the emptying of the medication container Fig. 5: Detailed longitudinal section through the proximal part of the first embodiment Fig. 6: Perspective view of a second embodiment Fig. 7: Exploded view of the second embodiment Fig. 8a: Top view of the distal end of the second embodiment Fig. 8b: Longitudinal section A-A through the second embodiment in the exit to Fig. 8c: Longitudinal section BB through the second embodiment in the initial state Fig. 9a: Top view of the distal end of the second embodiment Fig. 9b: Longitudinal section E-E through the second embodiment at the end of the last of the emptying of the medication container Fig. 9c : Longitudinal section F-F through the second embodiment at the end of the last of the emptying of the medication container Fig. 10a: Longitudinal section through the second embodiment with drawn cross-section K-K Fig. 10b: Cross-section K-K Fig. 11: Perspective view of a gear Fig. 12: Perspective view of a third embodiment Fig. 13: Exploded view of the third embodiment Fig. 14a: Top view of the distal end of the third embodiment Fig. 14b: Longitudinal section AA through the third embodiment in the initial state Fig. 14c: Longitudinal section BB through the third embodiment in the initial state Fig. 15a: plan view of the distal end of the third embodiment Fig. 15b: length Section G-G through the third embodiment after the last distribution Fig. 16a: Detail of the third embodiment, radial stop zero position Fig. 16b: Detail of the third embodiment, radial stop maximum adjustable dose Fig. 17: Detail of the third embodiment dose limit at Emptying of the product container Fig. 18a: Top view of recirculating ball nut Fig. 18b: Longitudinal section AA through recirculating ball nut Fig. 19a: Longitudinal section through combined tension and compression spring in a relaxed state Fig. 19b: Longitudinal section through combined tension and compression spring in pre-tensioned state 20: exploded view of a fourth embodiment; FIG. 21: longitudinal section through an injection pen of the fourth embodiment in the initial state. Fig. 22: Detailed view of the traveling wave motor

Figure description

In the following, preferred forms of an injection device are described for which the invention could be used, in particular injection pens with automatic distribution. This description is in no way intended to be interpreted in a restrictive manner, but merely to show one possible embodiment.

The first embodiment described below is an injection pen with a spring drive, with which several doses can be administered with a selectable dose. The injection pen is designed as a disposable pen, which means that the pen is disposed of after the reservoir has been completely emptied and cannot be reused, for example by exchanging the medication container. The injection pen of the first embodiment is shown in perspective in FIG. Fig. 2 shows the injection pen 1 in an exploded view. 3a to 5 show plan views or longitudinal sections through the injection pen 1. The injection pen 1 comprises a proximal housing 6 and a carpule holder 4. The housing 6 and the carpule holder 4 can be connected to one another via a snap connection. To this end, 4 snap lifts 4a are attached to the proximal end of the carpule holder. At the distal end of the housing 6, corresponding complementary elements (not shown) are arranged on the inside thereof, which complementary elements can snap onto the snap protrusions 4a. In this first embodiment, the medicament container is a classic carpule 5 as used in many injection devices. It has a filling volume of 3 ml, whereby other sizes such as 1.6 ml, 2 ml, or 6 ml are also conceivable and possible. The carpule is pushed into the carpule holder 4 during assembly. After the housing 6 and the carpule holder 4 have been snapped together, the carpule 5 is fixed axially and radially; it is mounted immovably in the injection device 1.

The commercially available injection needle 3 can be attached to the distal end of the carpule holder. The carpule holder 4 with and without an attached injection needle 3 can be protected by the protective cap 2. For this purpose, the protective cap 2 can be placed on the carpule holder and fixed via a releasable snap connection (not shown).

The mechanism holder 7 is arranged axially fixed and rotatable in the housing 6, the flanges 7a being guided in an annular groove (not shown) on the inside of the housing 6. The grid arms 7b are arranged on the flanges 7a. If the mechanism holder 7 is rotated relative to the housing 6, the grid arms are guided over a set of teeth (not shown) arranged on the inside of the housing 6, which on the one hand leads to an audible noise and to tactile feedback about the vibration caused. On the other hand, the mechanism holder 7 can thereby assume, in particular, discrete preferred positions, the spacings of which can preferably correspond to individual dose steps. The display 8 is axially firmly snapped to the mechanism holder 7. For this purpose, the groove 7c is arranged at the distal end of the mechanism holder 7, in which the snap elements 8c of the display can engage 8 (see FIG. 3c). The display 8 is rotatably mounted on the mechanism holder 7. The dose scale 8a (numbers not shown), which is visible through the window 6a of the housing (in the assembled state), is arranged on the outer surface of the display. Furthermore, a radial two-sided stop 8e in the form of an axially oriented rib is arranged on the outside of the display 8.

The housing insert 10 is arranged in an axially fixed and rotationally fixed manner in the housing. Two radial stops 10a and 10b which are complementary to the two-sided stop 8e are arranged on the housing insert 10. These limit the rotation of the display 8 relative to the housing. The stop for the zero position 10a limits the rotation of the display 8 by engaging with the stop 8e when it rotates in the counterclockwise direction. The stop for the maximum dose 10b limits the clockwise rotation of the display 8 by engaging with the stop 8e of the display 8. The possible angle of rotation between the stops 10a and 10b thus determines the possible adjustable dose.

On the inside of the display 8, threaded elements 8b are arranged, which are in thread engagement with the external thread 9a of the output member 9. The output member 9 is mounted in the mechanism holder 7 so that it can be moved axially via the longitudinal groove 9b and is secured against rotation. For this purpose, a longitudinal rib (not shown) is arranged on the inside of the mechanism holder 7, which rib engages the longitudinal groove 9b.

As can be seen in FIGS. 3b and 3c, the output member 9 is sleeve-shaped. While the distal end of the output member 9 is closed by the distal end surface 9c, the proximal end is open. The compression spring 11 is pushed into the proximal end of the output member 9. The distal end of the compression spring 11 is supported on the distal end surface 9c. The proximal end of the compression spring 11 is supported by the closed proximal end face 7d of the mechanism holder 7. When assembling the injection pen 1, the compression spring 11 is first pushed into the output member 9. The output element 9 is then pushed into the mechanism holder 7 against the force of the spring, whereby the compression spring 11 is tensioned and stores enough potential energy to empty the entire carpule 5.

The dosing button 13 is arranged at the proximal end of the housing, as shown in FIG. 3c. This dosing button 13 is fixed axially and rotationally to the mechanism holder. The push button 12, which is guided through the dosing button 13 into the interior of the injection pen 1, is also arranged at the proximal end of the housing 6. The two arms 12d lead up to the window 6a of the housing. The arms 12d partially encompass the mechanism holder 7. The arms 12d are guided in an axially movable manner by the guides 7e of the mechanism holder 7 and are secured against rotation.

As mentioned, the push button 12 is passed through the dosing button 13. The arms 12d are guided axially on the guide ribs 13a so that a relative axial movement between the push button 12 and the dosing button 13 is possible, but a relative rotation is prevented. On the outside of the push button 12, the push button spring elements 12a are arranged. These push button spring elements 12a press against the inside of the dosing button 13; their formal design (see FIG. 2) causes the push button to be pushed in the proximal direction. 5 shows a longitudinal section through the proximal area of the injection pen 1 through the push button spring elements 12a. The push-button spring elements 12a are beveled at their distal end and press on the snap-on tooth 13b of the dosing button. If the push button 12 is now displaced in the distal direction, the push button spring elements 12a are deflected radially inward, which, due to the elastic nature of the deformation, results in a restoring force in the proximal direction. The movement of the push button in the proximal direction is limited by a snap between the snap teeth 13b and the snapper 12g. The push button spring elements 12a limit the movement of the push button 12 in the distal direction. This embodiment has two clutches. A first coupling K1 detachably couples the push button 12 to the display 8. At the distal end of the arms 12d there are coupling members 12e which, when the injection pen 1 is idle, are in coupling engagement K1 with complementary coupling members 8d of the display 8, whereby a rotation lock between the pushbutton 12 and display 8 is formed.

A second coupling K2 releasably couples the push button 12 to the housing 6. The coupling members 12f are arranged on the jacket of the push button 12. If the push button 12 is pressed against the force of the push button spring elements 12a in the distal direction, the coupling members 12f come into engagement with the coupling members 6b of the housing 6. In Fig. 3b the push button is in its rest position, in Fig. 4b the push button is in the distal direction pressed. The comparison of the two figures shows how the push button 12 and thus the coupling members 12f move in the distal direction and the coupling K2 thus close. As a result, when the clutch K2 is closed, the housing 6 and the push button 12 are secured against rotation against one another.

When the injection pen 1 is idle, clutch K1 is closed and clutch K2 is open. The coupling members 12e and 12f are now arranged in such a way that when the pushbutton 12 is moved in the distal direction, K2 preferably closes first and the clutch K1 only opens when the pushbutton 12 is moved further.

The push button is threadedly engaged with the internal thread 14a of the stop ring 14 via the thread 12b. This stop ring 14 is mounted in the housing 6 so as to be axially displaceable but secured against rotation. For this purpose, longitudinal ribs 14b are arranged on the outside of the stop ring 14, which are guided on the inside of the housing by guides (not shown). On its proximal side, radial stops 14c are arranged on the stop ring 14 which engage with radial stops 12c of the push button when the stop ring 14 is screwed onto the proximal end of the thread 12b. The function of the stop ring 14 is to prevent a dose from being set which is greater than the remaining amount of medicament still present in the carpule 5. The exact functionality is explained in more detail below.

The mode of operation of the injection pen 1 will now be explained below. The injection pen 1 is delivered to the person using it with the carpule inserted. Before use, the protective cap 2 is removed and the injection needle 3 is attached. Then, if necessary, the carpule can be vented, so-called priming. To set a dose, proceed as follows (priming proceeds analogously with a small set dose and without piercing the injection needle into tissue). The dosing button 13 is rotated clockwise relative to the housing 6. Due to the existing anti-rotation devices, the push button 12, the mechanism holder 7, the output member 9 rotate with the dosing button 13. Since the push button 12 remains in its proximal rest position when the dose is set, K1 is closed, whereby the display 8 is also secured against rotation with respect to the dosing button 13 and rotates with the dosing button 13 when dosing. As a result, mechanism holder 7, output member 9 and display 8 are secured against rotation in this state, which means that compression spring 11 also rotates, the relative axial position of output element 9 and mechanism holder 7 remains unchanged, and the compression spring is neither tensioned nor tensioned is relaxed. Since the display 8 rotates with the dosing button 13, the set dose can be read in the window 6a. If the dose is set too high by mistake, the dose button can simply be turned back in the opposite direction until the desired dose is reached. The possible rotation of the dosing button 13 when setting and correcting the dose is limited by the radial stops 10a and 10b, which come into engagement with the radial stop 8e of the display 8 at the zero position and the maximum dose that can be set, since the display 8 is opposite the dosing button is secured against rotation.

After the desired dose has now been set, the injection needle 3 is inserted into tissue at the desired location. The push button 12 is then moved in the distal direction, whereby K2 is closed first and K1 is opened with further movement. Closing K2 has the effect that the push button 12 and consequently also the dosing button 13, the mechanism holder 7 and the output member 9 are secured against rotation relative to the housing 6 via the anti-twist devices. As long as K1 is still closed, the display 8 is also secured against rotation with respect to the housing. If the push button 12 is moved further in the distal direction, K1 is opened. Now the display 8 is no longer secured against rotation with respect to the push button 12 and is therefore also rotatable relative to the mechanism holder 7. The mentioned threaded connection exists between the display 8 and the output member 9. The compression spring 11 exerts a force in the distal direction on the distal end surface 9c of the output member 9. Since the output member 9 is mounted displaceably in the mechanism holder 7, there is a force which can cause the output member 9 to be displaced in the distal direction. After opening K1, the display 8 is still axially fixedly mounted on the mechanism holder, but is now rotatable relative to the housing 6 and the mechanism holder 7 (in the area between the stops 10a and 10b). Since the threaded connection between the output member 9 and the display 8 is not designed to be self-locking, the force of the compression spring 11 on the output member 9, thus on the threaded connection and consequently on the axially fixed display, induces a counterclockwise rotation of the display 8 back towards the zero position . As a result of the rotation of the display 8 relative to the output member 9, the output member 9 is displaced in the distal direction relative to the display 8 and thus to the mechanism holder 7 and the housing 6. The distal end surface 9 then presses on the stopper 5a of the carpule 5 and causes a displacement of the stopper 5a in the distal direction, whereby the volume in the carpule 5 is reduced and finally medicament is pressed through the pen needle 3 into the tissue. The display 8 rotates until the radial stop 8e comes into engagement with the stop 10a for the zero position. The engagement stops the rotation, whereby the movement of the output member 9 in the distal direction is also stopped. The push button 12 can now be released and, driven by the restoring force of the push button spring elements 12, moves back into the starting position, whereby first the clutch K1 is closed and then the clutch K2 is opened. The next dose can then be set on the injection pen.

When setting a dose, the dosing button 13 is rotated relative to the housing 6. The push button 12 is thus also rotated relative to the housing 6. As mentioned above, the arms 12d are in threaded engagement with the stop ring 14, which in turn is mounted in the housing 6 so as to be axially displaceable but secured against rotation. If a dose is set, the stop ring 14 moves, induced by the rotation of the push button 12, in the proximal direction. When a set dose is administered, the push button 12, like the stop ring 14, is secured against rotation with respect to the housing 6 due to the closed clutch K2, and there is no relative movement between the stop ring 14 and push button 12. Every time a new dose is set, the stop ring continues to move in the proximal direction (or in the distal direction if the dose just set is reduced) until the radial stops 14c of the stop ring and 12c of the push button engage when the dose just set is increased advised, whereby a further relative rotation between the stop ring 14 and push button 12 is prevented and consequently prevents a further increase in the dose just set by turning the dosing button 13 relative to the housing. It is immediately clear to the person skilled in the art that this function can be used to prevent the setting of a dose which exceeds the residual amount of medicament present in the carpule 5. For this purpose, the distance between the starting position (i.e. when the carpule is full) of the stop ring 14 relative to the radial stop 12c of the push button 12 is selected such that it corresponds to the amount of medicine present in the carpule 5 and / or the total amount of medicine to be dispensed.

The second embodiment according to the invention shown is also a spring-driven injection pen. This injection pen 100 is shown in FIG. 6 and does not differ externally from the injection pen 1. FIG. 7 shows an exploded view of the injection pen 100, which shows some differences between the pen 1 and the pen 100. 8a to 10b show different sections through the injection pen 100. Differences arise in the mechanics.

The first difference is found in the drive spring. The spring 111 is a torsion spring which, when assembling the injection pen 100, is tensioned by so many revolutions that it stores enough energy to empty the entire contents of the carpule 5. The torsion spring 111 is stretched between the dosing button 113 and the display 108 and is firmly connected at the respective ends 111a, 111b to the display 108 and the dosing button 113, in particular positively, to the spring fastening element 108e and 113a respectively (see Fig. 10a). As explained further below, when the injection pen 100 is in the idle state, the display 108 and push button 112 are secured against rotation against one another via the clutch K1 ', so that the torsion spring 111 can neither tension nor relax in the idle state.

Another difference arises in the case of the transmission unit which operatively connects the display 108 to the output member 109. Display 108 and output member 109 are connected to one another via at least one, preferably two gearwheels 115. The gears 115 each have two part gears 115a and 115b, respectively, which have different diameters, in particular pitch circle diameters. This means that the movement of the display is not transmitted 1: 1 to the output member 109, but the movement is stepped up or stepped down.

The housing insert 110 with the stops for the zero position 110a or for the maximum adjustable dose 110b is firmly anchored in the injection pen 100. The mechanism holder 107 is snapped onto the housing insert 110. The mechanism holder 107 is rotatably mounted on the housing insert 110. Movement in the proximal direction of the mechanism holder 107 relative to the housing insert 110 is prevented by the flange 107f. In the opposite direction, the catches 107g block the relative movement. The output member 109 is pushed into the mechanism holder 107. The output element 109 is mounted in the mechanism holder 107 so that it can be axially displaced but is secured against rotation. The output member is designed as a piston rod and, apart from the area of the distal end surface 109c, has a non-circular cross section. The output member 109 has two axial guide grooves 109d (see FIG. 10b). Complementary to this, the mechanism holder 107 has the guides 107e (only shown from the outside, see FIG. 7), which engage in the grooves 109d and thus guide the output member. The groove 107c runs circumferentially in the proximal area of the mechanism holder 107. The gears 115 are arranged in the distal area of the mechanism holder 107. The axis of rotation Q of the gears 115 is perpendicular to the longitudinal axis L of the injection pen 100, the axes L and Q in particular intersecting. The gears 115 are mounted by the mechanism holder via the bearing pin 115c, the bearing surface 115d and the support 115e in such a way that they can rotate about the axis Q. A gear of the second embodiment is shown in FIG. The partial gears 115a and 115b are clearly visible. The bearings 115c, 115d, 115e can also be seen in this illustration. 10b shows the arrangement of the output member 109, mechanism holder 107, two gear wheels 115 and the display 108 in the assembled state. The display 108 holds the two gears 115 in their bearings in the mechanism holder 107. Alternatively, it would also be possible for adapted gears to be snapped into the mechanism holder 107 in the area of the bearing 107h and mounted so as to be rotatable.

In the second embodiment, the display 108 is designed as an elongated sleeve into which the mechanism holder 107 can be inserted. In the proximal area of the display 108, the snap-in ribs 108c (see FIG. 8c) are formed complementary to the groove 107c, through which the display 108 can be axially fixed to the mechanism holder 108 so that a relative rotation between mechanism holder 107 and display 108 remains possible . The scale drum 108a is arranged in the distal region of the display 108. Compared to the rest of the display 108, the scale drum 108a has a larger diameter. In preferred embodiments of the display 108, this can be formed in one piece with the scale drum 108a. Alternatively, however, it is also possible for the display to be assembled from several parts, for example from the graduated drum and a second partial sleeve. A metering scale is arranged on the outside of the graduated drum 108a and can be seen through the window 106a of the housing. As can be seen in FIG. 7, the display 108 has a toothing 108b. The teeth 108b extend over the entire circumference, the individual teeth are directed axially in the distal direction. In the assembled state of the injection pen 100, the teeth 108b mesh with the teeth of the partial gears 115b and are thus functionally connected to the gears 115. As a consequence, a relative rotation about the axis L between the mechanism holder 107 and the display 108 has the consequence that the gear wheels 115 are set in rotation.

As mentioned, the output member 109 is designed as a piston rod. The grooves 109b each have a base and two side surfaces. In each case one of the side surfaces has a toothing 109d which, in the assembled state, engages in the toothing of a partial gearwheel 115a and is thus functionally connected to one of the gearwheels 115. This has the consequence that when the gearwheels 115 rotate about the axis Q, the output member 109 then moves in the axial direction.

The teeth 108b together with the gears 115 and the teeth 109d together result in the transfer device of the injection pen. That is, when the display 109 is rotated relative to the mechanism holder 107, the gears 115 are set in rotation and as a result of this the output member 109 moves in the axial direction. Via the size ratio of the pitch circle diameters of the partial gears 115a and 115b and the pitch circle diameter of the toothing 108b, the relative movement between display 108 and output member 109 is increased or decreased.

The dosing button 113 is rotatably but axially firmly snapped to the housing 106, for this purpose the snapper 113b is arranged on the dosing button 113 and a complementary recess (not shown) is arranged on the inside of the housing 106. The push button 112 is connected to the dosing button 113 in a rotationally fixed and axially movable manner and is pushed into the dosing button 113. At the same time, the push button 112 is rotatably snapped to the housing 106 as described below. In the axial direction, the push button 112 is movable to a certain extent with respect to the housing 106. The snap arms 112b of the push button limit the movement of the push button 112 in the proximal direction due to the aforementioned complementary recess on the housing, which also holds the dosing button 113. In the distal direction, the movement of the push button 112 is restricted by the dosing button. The push button spring 112a is clamped between the dosing button 113 and the push button 112 and pushes the push button 112 in the proximal direction. In the rest position, the push button 112 is in its proximal end position. The push button 112 is connected to the toothing 107i of the mechanism holder 107 via the teeth 112 c (see FIG. 7), with the effect that the push button 112 and mechanism holder 107 are secured against rotation with respect to one another, but can move axially to one another.

As with the first embodiment, the second embodiment also comprises two couplings, see FIGS. 7 and 9b. K1 'is a coupling with which the push button 112 is coupled to the display 108. This clutch is closed in the idle state. It is formed by the coupling teeth 112d on the push button 112 and 108d on the display 108. In Fig. 9b, the push button 112 is shifted in the distal direction and the clutch K1 'is open, which means that a relative rotation between the push button 112 and the Display 108 is possible. In contrast, FIG. 8b shows the push button 112 in its rest position (i.e. proximal), in this state the clutch K1 'is closed and a relative rotation between the push button 112 and display 108 is not possible. K2 'is a coupling with which the push button 112 can be coupled to the housing 106. The clutch K2 'is closed by pushing the push button 112 in the distal direction. As a result, the coupling members 106b of the housing come into engagement with the coupling elements 112e of the push button 112, whereby the push button 112 is secured against rotation with respect to the housing 106 (see FIGS. 7, 8b and 9b). The coupling teeth 112d and the coupling elements 112e are arranged on the push button in such a way that when the push button 112 is moved in the distal direction, K2 'is first closed and then the coupling K1' is opened.

The torsion spring 111 of the injection pen 100 is tensioned when the injection pen is assembled.

For the person using the injection pen 100 works the same as the injection pen 1. To set or correct a dose, the person using rotates the dose button 113 about the axis L, thereby making the corresponding dose visible through the window 106a, because with the Dosing button 113 also rotate the push button 112, the mechanism holder 107, the output member 109 as well as the display 108 due to the clutch KV being closed when the push button 112 is in the idle state. The torsion spring 111, in particular the ends 111 a and 111 b of the torsion spring, also makes the rotational movement. Since push button 112 and display 108 rotate by identical angles, the torsion spring 111 is neither tensioned nor relaxed. To increase the dose, the dose button 113 is turned clockwise, to correct it in the opposite direction. The zero position and the position of the maximum dose are marked by the radial stops 108e, 110a and 108g, 110b, respectively. The display 108 can therefore only be moved over an angle of less than 360 °. This also limits the rotation of the dosing button 113 via the clutch K1 ́. When the desired dose has been set, the push button 112 is moved in the distal direction by pressing, whereby, as mentioned, the clutch K21 is first closed and then the clutch K1 'is opened. By closing K2 ', the push button 112 and the proximal end 111b of the torsion spring 111, the dosing button 113, the mechanism holder 107 and the output member 109 are rotatably fixed with respect to the housing. By subsequently opening K1 ́, the display 108 can rotate relative to the push button 112. Since the torsion spring 111 is pretensioned, a torque acts on the display which, after the clutch K1 'is opened, causes the display 108 to rotate (relative to the elements which are secured against rotation with respect to the housing). Thus, the display 108 rotates counterclockwise from the set dose in the direction of the zero position, at which the rotation of the display 108 relative to the housing 106 is stopped by the radial stops 108e and 110a. As already mentioned above, a relative rotation between the display 108 and the mechanism holder 107 causes a rotation of the gears 115 and consequently a displacement of the output member 109 in the axial direction. A relative rotation of the display 107 in the counterclockwise direction causes an axial displacement of the output member 109 in the distal direction. As a result, the distal end surface 109c of the output member 109 can move the stopper 5a of the carpule 5 in the distal direction, whereby medicament is pressed out of the carpule 5. After the stops 108e and 110a are in engagement and the movement has stopped, pressing the pushbutton 112 can be stopped, whereby the pushbutton 112 moves again into the proximal rest position via the action of the pushbutton spring 112a. During the movement, first clutch K1 ́ is closed and then clutch K2 ́ is released. The injection pen 100 is then ready for the next dose selection.

In the version shown, the injection pen 100 has no function with which the setting of a dose which exceeds the residual amount of medicament present in the carpule 5 is prevented. However, this function could be implemented in injection pen 100 analogously to injection pen 1. For this purpose, the push button 112 would have to be lengthened in the distal direction and provided with an external thread on its outside. Correspondingly, a stop ring would then be arranged on the thread, which would be displaceable with respect to the housing but mounted in a manner secured against rotation.

In the variants shown, the output members 9, 109 described in the two embodiments have distal end surfaces 9c, 109c which move the stopper 5a of the carpule 5 in the distal direction. As can be seen from the above description, the output members 9, 109 rotate relative to the stopper 5a when setting or correcting a dose. As a result, in order to set or correct a dose, friction between the proximal end face of the stopper 5a and the distal end face 9c, 109c has to be overcome. This can have a negative effect on the dispensing experience of the person using it, as the person has to apply additional force when dispensing, on the one hand, and on the other hand, dispensing can become uncomfortable through stick / slip effects. It is also the case that the stopper 5a of the carpule 5 or the carpule 5 itself should not rotate during the dosing movement in order to be able to ensure the container closure integrity of the carpule 5. Therefore, in advantageous configurations of the two embodiments, the output members 9, 109 are configured in several parts, in particular in two parts. The distal end surfaces 9c, 109c are designed as separate flanges, which are arranged on the output members 9, 109 via a low-friction and low-torque connection. For this purpose, the flange and the output member can be snapped together. For this purpose, the snap connection can be designed as a low-friction sliding bearing. For example, a spherical head can be arranged at the distal end of the output member 9, 109, which is snapped onto the flange with a complementary cavity. If the output member 9, 109 is now rotated relative to the plug 5a during the metering process, the relative rotation between the flange and the output member 9, 109 can take place with little friction. The selection of the materials of the flange and output member 9, 109 is also advantageous for this purpose, so that the friction between the two elements is minimized. Examples of materials that can be used are polyoxymethylene, polybutylene terephthalate or fiber-reinforced polymers such as polyamides. Alternatively, such a multi-part design can be dispensed with in that the friction between the stopper 5a and the distal end surfaces 9c, 109c is reduced by suitable material pairing and / or shaping, in particular by using a lubrication.

The third embodiment according to the invention shown is also a spring-driven injection pen. This injection pen 200 is shown in FIG. 12 and does not differ significantly from the outside of the injection pen 1. FIG. 13 shows an exploded view of the injection pen 200, which shows some differences between the pen 1 and the pen 200. 14a to 15b show different sections through the injection pen 200. Differences result in the mechanics, the kinematics and in particular the operation being basically the same in both embodiments. The injection pen 200 is a so-called disposable pen, which allows several doses of variable sizes to be administered. After the carpule 5 has been emptied, the injection pen 200 is properly disposed of. The carpule holder 4 is snapped into place during assembly with the housing 206 via the elements 204a and 206a, respectively.

The biggest difference between the pen 1 and the 200 is to be found in the transmission unit and the display 208 connected to it. In this third embodiment, the transmission unit comprises a ball screw drive. The advantage of this embodiment is the low friction during relative movement between display 208 and output member 209. Display 208 is designed as a cylindrical sleeve and has a scale 208a on its outside which indicates the dose setting through housing opening 206a. The display 208 further comprises an external thread 208h which is in thread engagement with the internal thread 206d of the housing. In contrast to the first embodiment, when a dose is set, the display 208 is not only rotated by rotating the dosing button 213, but performs a screwing movement relative to the housing. For the maximum dose, the dosing movement is restricted at the radial stop 206e, or at the radial stop 204b of the carpule holder 4 for the zero position, as can be seen in FIGS. 16a and 16. For this purpose, the stops 208g, respectively. 208e arranged, both advantageously designed as radial stops. The display 208 is secured against rotation and guided axially displaceably on the recirculating ball nut 216. For this purpose, the longitudinal ribs 216 are arranged on the nut and, complementary thereto, the longitudinal grooves 208i on the display 208. The recirculating ball nut 216 is shown separately in FIGS. 18a and 18b. The recirculating ball nut 216 has, on the one hand, the recirculating ball thread 216c and, on the other hand, also a ball bearing 216d. The balls 216b for the elements 216c and 216d, respectively, are introduced through the opening 216g during the assembly of the injection pens 200, then the opening 216g is closed with the cover 216f. The recirculating ball nut 216 is axially fixed but rotatably connected to the mechanism holder 207 via the balls 216b of the ball bearing 216d. Via the coupling elements 216e, the recirculating ball nut 216 is releasably connected to the pushbutton 212 in a manner secured against rotation via the coupling members 212e of the pushbutton 212. Analogously to the first embodiment, the coupling is released by pressing the push button in the distal direction. The recirculating ball nut 216 is via the balls 216b in the thread 216c in a non-self-locking thread connection to the external thread 209a of the output member 209. As a consequence of a rotation of the display 208 relative to the output member 209, an axial displacement of the output member relative to the mechanism holder 207. The present injection pen 200 has the advantage over the injection pen 1 that the friction in the transfer unit can be reduced. Second, the arrangement of nut 216 and display 208 allows a dispensing movement on the dispensing knob 213 of more than 360 °.

Another difference between the first and third embodiment relates to the energy store. In the first embodiment, the compression spring 11 is provided as an energy store. In the third embodiment, a combined tension and compression spring 211 is provided. 19a shows a longitudinal section through the spring 211 in the relaxed state and FIG. 19b shows the spring 211 in a tensioned state. The spring 211 consists of an inner partial spring 211 a, which functions as a tension spring, and an outer partial spring 211 b, which functions as a compression spring. 14b shows the spring 211 in the pre-tensioned state in the injection pen 200. The spring is tensioned between the spring bearing 207I and the distal end surface 209c between the mechanism holder 207 and the output member 209. The spring bearing 207I is connected to the distal end of the inner partial spring 211b and the distal end of the second partial spring presses on the distal end surface 209c. In the pretensioned state, the inner partial spring 211a is expanded compared to its rest state, which means that a force is applied to the spring bearing 207I in the proximal direction. In FIG. 14b, the outer partial spring is compressed in relation to its rest state, which means that a force acts in the distal direction on the distal end surface 209c. In advantageous embodiments, the spring 211 is wound on a single piece of wire. Alternatively, the spring 211 can also be composed of two individual sub-springs. The advantage of the combined tension and compression spring 211 compared to the compression spring 11 from the first embodiment is that the spring 211 has a linear force / path ratio over a greater distance. As a consequence, this means that shorter designs of an injection device are possible if a spring such as spring 211 is used. In principle, the spring does not change the kinematics of the injection pen, which is why it could also be used in the first embodiment. Only the mechanism holder 7 would have to be changed, analogously to mechanism holder 207. FIG. 15 a shows the injection pen 200 after the last discharge with the spring 211 correspondingly relaxed.

Injection pen 200, like injection pen 1, has a device in order to limit the maximum dose that can be dispensed depending on the contents of carpule 5. The mechanism consisting of housing 206, stop ring 214 and push button 212 functions in the same way as in the case of injection pen 1. FIG. 17 shows the state of the injection pen 200 when the carpule is empty. The stop ring 214 is in engagement with the stop 212c of the thread 212b of the push button via the stop 214c.

20 to 22 show a fourth embodiment of an injection pen in accordance with the invention. As in the first and the third embodiment, the transmission unit is basically designed as a threaded connection. In contrast to the preceding embodiments, at least the dosing button, the push button, the display and part of the transmission unit are implemented electrically or electronically. The display 308 is a flexible electronic display, for example in the form of a flexible OLED display, which is arranged on the housing 306. The dosing button is also arranged on the housing as a touch-sensitive area 313. Printed markings 313d indicate the direction in which the area must be swept with a finger in order to increase or decrease the dose. The set dose is shown on display 308. The display 308 and the touch-sensitive area 313 are protected from unwanted environmental influences by a transparent protective cover 306 '. The injection pen 300 also includes corresponding control electronics (not shown) and a memory for storing electrical energy (not shown) in the form of a battery, an accumulator, or a capacity.

In the first and the third embodiment, two stops, namely one of the display and one fixed to the housing, are moved away from one another during the dosing movement. By subsequently decoupling the display and the push button, a relative rotation between the output member and the display is possible, with the axial force of the springs provoking a propulsion of the output member. In the fourth embodiment, the distribution is no longer controlled by a clutch and stops, but by electronics and a motor. The motor is arranged coaxially to the output member 309 between the housing 306, which includes the display 308, and the output member. In the embodiment shown here, the motor consists of an annular stator 317 and an annular rotor 318. The motor is a so-called traveling wave motor, in which a mechanical traveling wave is excited piezoelectrically, which in turn actively sets the rotor 318 in rotation. For this purpose, the piezo elements 317a are arranged on the stator 317, which are excited one after the other and thus generate the mechanical wave through the deformation of the individual elements 317a. The output member 309 comprises an external thread 309a which is in thread engagement with the internal thread 318a of the rotor 318. It can thus be determined that the transmission unit is basically designed as a threaded connection in the same way as in the first and the third embodiment. In contrast to the first and third embodiment, the threaded connection 318a / 309a is a self-locking threaded connection, so that the axial force of the spring 311 is not sufficient to provoke a propulsion of the output member 309. The axial movement of the output member 309 is only possible by actively rotating the rotor 318. In the fourth embodiment, the self-locking has the advantage that the spring 311 can not only be used to propel the output member, but also serves, via the thread, to press the rotor 318 onto the stator 317 in order to eliminate as much friction between the stator 317 and To produce rotor 318 that the traveling wave on the stator 317 can set the rotor 318 in rotation.

The electronic control system advantageously also includes a clock which, in particular, can display the time that has passed since the last injection on the electronic display 308. The electronics can also be used to indicate memories on the display 308 or an acoustic or tactile emitter to the person using it. The electronics can also be designed in such a way that the point in time and administration dose can be stored, in particular data on several injections.

The following can also be stated: At least comprising an injection device for administering a fluid medicament substance an elongated housing (6.106) with an insert (10, 110) fixed therein and a longitudinal axis L, a holder for a medicament substance container (5) which is attached to the distal end of the housing (6, 106) and which contains a movable element (5a) for expressing medicament, an energy store (11, 111) which releases energy for administering drug substance, the energy store being able to store enough energy to be able to empty at least one entire drug substance container (5), a sleeve-shaped mechanism holder (7, 107) which is axially fixed but rotatably attached to the insert (10, 110) about the longitudinal axis L, a dosing element (13, 113), which is axially fixed but rotatable about the axis L at the proximal end of the housing (6, 106), the dosing element (13, 113) for setting a dose about the axis L relative to the housing ( 6, 106) can be rotated, a push button (12, 112) which is arranged on the dosing element (13, 113) so as to be secured against rotation and extends through the dosing element (13, 113), the push button being connected to the mechanism holder in a way that is secured against rotation and slidable through the area extending through the dosing element is a sleeve-shaped display element (8, 108) which is axially fixed and rotatable on the mechanism holder (7, 107), an elongated output device (9, 109), in particular a piston rod, which is mounted in the mechanism holder (7, 107) in a rotationally fixed and axially displaceable manner along the axis L, the output device (9, 109) moving the movable element (5a) in the distal direction ) can move to squeeze out drug substance, a first coupling (K1, K1 ́) with which the push button (12, 112) and the display element (8, 108) can be coupled in a rotationally fixed manner, a second coupling (K2, K2 ́), with which the push button (12, 112) and the housing (6, 106) can be coupled in a rotationally fixed manner, a transmission device which functionally couples the display element (8, 108) to the output device, so that a rotation of the display element (8, 108) relative to the mechanism holder (7, 107) results in an axial displacement of the output element (9, 109) relative to the mechanism holder ( 7, 107) and vice versa, whereby the clutches (K1, K1 ́, K2, K2 ́) are actuated by moving the push button axially, characterized in that When setting and correcting a dose, the first clutch (K1, K1 ́) is closed, the second clutch (K2, K2 ́) is open, the dose is set by rotating the dosing button (13, 113) the push button (12, 112) for administering the set dose is moved in the distal direction, whereby first the second clutch (K2, K2 ́) is closed and then the first clutch (K1, K1 ́) is opened and that during the administration of the energy store (11, 111) operatively acts on the display element (8, 108), which rotates and the transmission device causes an axial displacement of the output device (9, 109). • An injection device characterized in that a dose scale (8a, 108a) is arranged on the outside of the display element (8, 108), which is partially visible through the opening or window (6a, 106a) and when setting and correcting a dose the set dose can be read in the opening or window of the housing (6a, 106a). • An injection device characterized in that the transmission device is formed by a threaded connection (8b, 9a) between the display element (8) and the output member (9). • An injection device characterized in that the energy store (11, 111) is a compression spring (11) which is pretensioned between a bearing surface (9c) of the output member (9) and a bearing surface (7d) of the mechanism holder (7). • An injection device characterized in that the transmission device comprises at least one gearwheel (115), the at least one gearwheel (115) being mounted on the mechanism holder (107) so as to be rotatable about an axis (Q) and the axis (Q) being transverse to the longitudinal axis (L), further characterized in that that the display element (108) is in operative engagement with the gear (115) and a rotation of the display element (108) about the axis L relative to the mechanism holder (107) causes the at least one gear (115) to rotate about the axis (Q), and that the at least one gear (115) is in operative engagement with the output member (109) and a rotation of the at least one gear (115) about the axis (Q) results in a displacement of the output member (109) relative to the mechanism holder (107). • An injection device according to claim 5, characterized in that the display element (108) comprises a toothing (108b) which is arranged on the inside of the sleeve-shaped display element and whose individual teeth are aligned in the axial direction. • An injection device characterized in that the output member (109) comprises a set of teeth (109d) extending in the axial direction, the individual teeth of which are approximately perpendicular to the longitudinal axis (L). • An injection device according to claims 6 and 7, characterized in that the toothing (108b) of the display element (108) engages in a first toothing (115b) of the gear (115) and the toothing (109d) of the output member (109) in a second Teeth (115a) of the gear (115) engages. • An injection device characterized in that the toothings (115a, 115b) are arranged on partial gears (115a, 115b) which have identical or different pitch circle diameters. • An injection device characterized in that the partial gears have different pitch circle diameters and either together form a one-piece gear (115) which is made from one part or consist of at least two parts which are assembled into a gear (115) and then immovably connected to one another are. • An injection device characterized in that the energy storage device (11, 111) is a torsion spring (111) which comprises a distal spring end (111a) and a proximal spring end (111b), the distal spring end (111a) being fixed to a spring fastening element (108f ) the display element (108) is arranged and the proximal spring end (111b) is fixedly arranged on a spring fastening element (113a) of the dosing element (113), and the torsion spring 111 is pretensioned by a relative rotation of the dosing element (113) and display element (108) . • An injection device characterized in that the housing insert (10, 110) comprises at least one radial stop (10a, 10b, 110a, 110b) and the display element (8, 108) comprises at least one radial counter-stop (8e, 108e, 108g) complementary thereto , wherein the interaction of the at least one radial stop with the at least one radial counterstop restrict the relative rotation between the display element (8, 108) and the housing insert (10, 110) in at least one direction. • An injection device characterized in that the rotation of the dosing button (13, 113) relative to the housing (6, 106) when setting and correcting a dose is detected qualitatively and / or quantitatively by at least one sensor, the at least one sensor generating a sensor signal , wherein the sensor signal is evaluated by an electronic circuit provided on the injection device. • An injection device characterized in that the sensor detects the rotation of the dosing button at least quantitatively and outputs a quantitative sensor signal and that the electronic circuit can convert the quantitative sensor signal into the effectively set dose. • An injection device characterized in that the electronic circuit has a display which can show the calculated dose.

Identifier

1 injection pen 2 protective cap 3 pen needle 4 carpule holder 4a snap lift 5 carpule 5a stopper 6 housing 6a window 6b coupling member 7 mechanism holder 7a flange 7b ratchet arm 7c groove 7d proximal end surface 7e guide 8 display 8a scale 8b threaded element 8c snap element 8d coupling element 8e radial stop 9 output member 9a external thread 9b longitudinal groove 9c distal end surface 10 housing insert 10a stop zero position 10b stop maximum dose 11 compression spring 12 push button 12a push button spring arms 12b thread 12c radial stop 12d arm 12e coupling member 12f coupling member 12g snap 13 dosing button 13a guide rib 13b snap tooth 14 internal stop ring 14b 14a Stop 100 injection pen 106 housing 106a window 106b coupling member 107 mechanism holder 107c groove 107e guide 107f distal flange 107g snapper 107h bearing 107i teeth 108 display 108a scale drum 108b teeth 108c snap-in ribs 108d coupling teeth 108e radial stop zero position 108f spring fastening element 108g radial stop maximum dose 109 output member 109b guide groove 109c distal end surface 109d toothing 110 housing insert 110a stop zero position 110b stop maximum dose 111 torsion spring 111a distal spring end 111b proximal spring end 112 push button 112a push button spring 112b snap arm 112c toothing 112d coupling toothing 112e coupling element 113 Snap 115 Gear 115a Part gear 115b Part gear 115c Bearing pin 115d Bearing surface 115e Support 200 Injection pen 204a Snap protrusion 206 Housing 206a Window 206c Snap opening 206d Thread 206e Radial stop 207 Mechanism holder 207j Groove 207I Spring bearing 208 Indicator sleeve 208a Scale 208h Thread 208i Longitudinal groove 209 Output member 209 209a Outer End face 211 combined tension and compression spring 212 push button 212b thread 212c stop 212e coupling members 213 dosing button 214 stop ring 214a internal thread 214b Lä ngsrippen 214c stop 216 recirculating ball nut 216a longitudinal rib 216b ball 216c thread 216d ball bearing 216e coupling elements 216f cover 216g opening 306 housing 306 ́ transparent protective housing 307 mechanism holder 308 display 309 output member 310 housing insert 311 combined tension and compression spring 313 contact-sensitive rotor 318a inner thread 317 stator 317 319 carpule spring L longitudinal axis Q transverse axis K1 clutch K2 clutch K1 ́ clutch K2 ́ clutch

Claims (15)

An injection device for administering a fluid medicament substance comprising at least an elongated housing (6, 106, 206) and a longitudinal axis L, a medicament substance container holder (5) attached to the distal end of the housing (6, 106, 206), which contains a medicament expressing movable member (5a), energy storage means (11, 111, 211) for administering energy Drug substance releases, the energy storage can store enough energy to at least a whole drug substance container (5) to be able to empty, a sleeve-shaped mechanism holder (7, 107, 207), which is fixed axially fixed to the housing (6, 106, 206) about the longitudinal axis L, a metering element (13, 113, 213), which is axially fixed but rotatable about the axis L at the proximal end of the housing (6, 106, 206), wherein the metering element (13, 113, 213) for setting a dose to the Axis L relative to the housing (6, 106, 206) can be rotated, a push button (12, 112, 212), which is arranged secured against rotation on the dosing (13, 113, 213) and by the dosing (13, 113, 213 ), wherein the push button (12, 112, 212) is secured against rotation and slidably connected to the mechanism holder (7, 107, 207) by the region extending through the metering element (13, 113, 213), a single or multi-part sleeve-shaped display (8, 108, 216/208), which is rotatably mounted on the mechanism holder (7, 107, 207), an elongated output device (9, 109, 209), in particular a piston rod, which is rotatably and axially along the axis L slidably mounted in the mechanism holder (7, 107, 207), wherein the output device (9, 109, 209) in displacement in distal Direction the movable element (5a) can move to squeeze drug substance, a first clutch (K1, K1) with which the push button (12, 112, 212) and the display (8, 108, 216/208) can be coupled in a rotationally fixed manner, a second clutch (K2, K2), with which the push-button (12, 112, 212) and the housing (6, 106, 206) can be coupled in a rotationally fixed manner, a transmission device operatively coupling the display (8, 108, 216/208) to the output device such that rotation of the display (8, 108, 216/208) relative to the mechanism holder (7, 107, 207) causes axial displacement of the display Output element (9, 109, 209) relative to the mechanism holder (7, 107, 207) result and vice versa, wherein the clutches (K1, K1, K2, K2) are actuated via an axial displacement of the push button, characterized in that when setting and correcting a dose, the first clutch (K1, K1) is closed, the second one Coupling (K2, K2) is opened, the dose is set by rotating the Dosierknopfs (13, 113, 213) that the push button (12, 112, 212) is moved in the distal direction for administering the set dose, thereby first closing the second clutch (K2, K2) and then opening the first clutch (K1, KV) and during the administration of the energy stores (11, 111, 211) acts on the display (8, 108, 216/208), which turns and the transmission device causes an axial displacement of the output device (9, 109). 2. Injection device according to claim 1, characterized in that the display (8, 108, 216/208) comprises a display element (8, 108, 208) which on the outside, a dose scale (8a, 108a, 208a) is arranged, which is partially visible through the opening or the window (6a, 106a, 206a) and when setting and correcting a dose, the set dose in the opening or the window of the housing (6a, 106a, 206a) is read. 3. Injection device according to claim 1 or 2, characterized in that the transmission device by a threaded connection (8b, 9a) between the display (8) and the output member (9) is formed. 4. Injection device according to claim 3, characterized in that the energy store (11, 111) is a compression spring (11) which is biased between a bearing surface (9c) of the driven member (9) and a bearing surface (7d) of the mechanism holder (7). 5. Injection device according to claim 1 or 2, characterized in that the transmission device comprises at least one toothed wheel (115), wherein the at least one toothed wheel (115) is mounted rotatably about an axis (Q) on the mechanism holder (107) and the axis (Q) is transverse to the longitudinal axis (L), further characterized that the indicator (108) is in operative engagement with the gear (115) and rotation of the indicator (108) about the axis L relative to the mechanism holder (107) causes the at least one gear (115) to rotate about the axis (Q), and that the at least one gear (115) is in operative engagement with the output member (109) and rotation of the at least one gear (115) about the axis (Q) results in displacement of the output member (109) relative to the mechanism holder (107). 6. Injection device according to claim 5, characterized in that the display (108) comprises a toothing (108b) which is arranged on the inside of the sleeve-shaped display element and whose individual teeth are aligned in the axial direction. 7. Injection device according to claim 5, characterized in that the output member (109) comprises an axially extending toothing (109d) whose individual teeth are approximately perpendicular to the longitudinal axis (L). 8. Injection device according to claims 6 and 7, characterized in that the toothing (108b) of the display (108) in a first toothing (115b) of the gear (115) engages and the toothing (109d) of the output member (109) in a second Teeth (115a) of the gear (115) engages. 9. Injection device according to claim 8, characterized in that the toothings (115a, 115b) are arranged on partial gears (115a, 115b) which have identical or different pitch circle diameters. 10. Injection device according to claim 9, characterized in that the partial gears have different pitch circle diameter and either together form a one-piece gear (115) which is made of one part or consist of at least two parts, which are assembled into a gear (115) and then are immovably connected with each other. 11. Injection device according to one of claims 8 to 10, characterized in that the energy store (11, 111) is a torsion spring (111) which comprises a distal end of the spring (111a) and a proximal spring end (111b), wherein the distal end of the spring (111a ) is fixedly arranged on a spring attachment element (108f) of the display element (108) and the proximal spring end (111b) is fixedly arranged on a spring attachment element (113a) of the metering element (113), and the torsion spring 111 is rotated by a relative rotation of the metering element (113). and display (108) is biased. 12. Injection device according to claim 1 with an insert (10, 110) fixed therein, characterized in that the housing insert (10, 110) comprises at least one radial stop (10a, 10b, 110a, 110b) and the display (8, 108) complementary to at least one radial counter stop (8e, 108e, 108g), wherein the interaction of the at least one radial stop with the at least one radial counter stop the relative rotation between the display (8, 108) and the housing insert (10, 110) in at least restrict one direction. 13. Injection device according to claim 1, characterized in that the rotation of the Dosierknopfes (13, 113) relative to the housing (6, 106) when setting and correcting a dose by at least one sensor is detected qualitatively and / or quantitatively, wherein the at least one sensor generates a sensor signal, wherein the sensor signal is evaluated by an electronic circuit provided on the injection device. 14. Injection device according to claim 13, characterized in that the sensor detects the rotation of the Dosierknopfes at least quantitatively and outputs a quantitative sensor signal and that the electronic circuit can convert the quantitative sensor signal into the effectively set dose. 15. Injection device according to claim 14, characterized in that the electronic circuit has a display which can display the calculated dose.