Drive for a drug delivery device

Abstract

The present application relates to a drive for a drug delivery device, the drive comprising a drive mechanism having a drive shaft, a pinion arranged on the drive shaft, and an oscillating drive. The oscillating drive has an oscillating disc and a ring gear. The oscillating disc is driven in an eccentric movement by means of a planetary gear, which engages with the pinion on the drive shaft and with an internal gear of the oscillating disc. Further, the present application also relates to a drug delivery device having the aforementioned drive.

Description

Technical Field

[0001] This invention relates to a driver for a drug delivery device, preferably for an automated injection device. Furthermore, the invention also relates to a drug delivery device having a driver. Background Technology

[0002] There are various diseases that require routine treatment via subcutaneous medicament administration, and several drug delivery devices have been developed to support patients in accurately and controllably delivering a certain amount of medication during self-administration. Delivery devices include injection devices that are removed from the injection site after each medication event or drug delivery process, and infusion devices with cannulas or needles that remain in the patient's skin for an extended period of time.

[0003] For example, diabetes can be treated by self-administering insulin or its derivatives with the help of a multivariable dose insulin pen.

[0004] Automated injection devices have a motor or drive spring for biasing the plunger rod and displacing the piston in the container barrel. The drive spring may need to be manually charged or strained before the dose is injected. Manually actuated delivery actuators require the user to manually provide energy to move the piston, for example, by applying a distal force component to the injection device.

[0005] The dosage of the medication to be injected can usually be manually selected by turning the dosage knob and observing the actual dose dispensed from the dosage window or display of the drug delivery device. Dosage is dispensed by inserting a needle into the appropriate portion of the skin and by manually moving the piston or by pressing the release button on the automatic injection device.

[0006] Several types of injection devices exist in the art. Single-use injection devices are suitable for delivering medications from containers, such as pre-filled cartridges or syringes, which are not intended to be replaced or refilled by the patient. Reusable, semi-disposable, or hybrid delivery devices have device components that can be replaced by the patient or refillable cartridges, while some parts of the device can be reused together with replaced or refilled medication containers.

[0007] Automated infusion devices with electric motors typically require appropriate gears to reduce the relatively high rotational speed of the motor to the relatively slow linear movement of a piston arranged within a container. Since the advancement of the piston requires some force, this gear needs to be able to transmit high torque as it is used to inject medication from the container into the patient through a needle or cannula. Furthermore, the gear arrangement should be compact so that the overall size of the infusion device remains small.

[0008] The prior art discloses the use of cycloidal actuators in drug delivery devices as suitable for meeting the standards mentioned above because cycloidal actuators are compact and offer high gear ratios. For example, US2007 / 0225657 proposes the use of cycloidal actuators to transmit rotational movement between a dose-setting mechanism and a rotary scale. Further, WO 2014 / 117944 describes the use of cycloidal actuators in dose-setting mechanisms. Summary of the Invention

[0009] The object of the present invention is to produce a driver for a drug delivery device that is small in size, provides a high gear ratio, and allows the transmission of high torque.

[0010] The solution of the present invention is specified by the features of claim 1. According to the invention, the actuator for a drug delivery device comprises a drive mechanism having a drive shaft, a pinion arranged on the drive shaft, and a cycloidal actuator. The cycloidal actuator has a cycloidal disk and a gear ring (preferably, a fixed gear ring). The cycloidal disk is driven to perform an eccentric motion by means of a planetary gear that meshes with the pinion on the drive shaft and with the internal gear of the cycloidal disk.

[0011] The inventive combination of a cycloidal actuator and a planetary actuator allows for an increase in the gear ratio of the cycloidal actuator without increasing the size of the gear arrangement, since the planetary actuator is located inside the cycloidal actuator. Furthermore, since planetary gears are well-suited for transmitting high torque, the torque transmission of the overall gear arrangement is not negatively affected. A further significant advantage of the actuator according to the invention is that it uses a very small number of different parts (i.e., only four parts besides the drive mechanism). Therefore, the actuator is very easy to assemble and can be manufactured at low cost.

[0012] The drive mechanism may include a manual drive mechanism, an electric drive (such as an electric motor), or a mechanical drive (such as a mechanical spring) or an elastic element adapted to be biased and released.

[0013] The electric motor can be of any suitable type, such as a brushed or brushless DC motor. Preferably, the electric motor includes a closed-loop control system, thereby allowing precise control of the electric motor (such as, for example, a servo motor). Of course, the electric motor should be small enough to be fitted into the housing of the drug delivery device in which the drive will be used.

[0014] The pinion is preferably permanently attached to the drive shaft of the drive mechanism, for example by means of press fitting, adhesive, or any other suitable means. Alternatively, the pinion may be integral with the drive shaft, and the pinion may be milled onto the drive shaft, for example.

[0015] The cycloidal actuator preferably uses a fixed or rotating gear ring and a cycloidal disk in a known manner. In a preferred embodiment, the gear ring includes a plurality of pins on its inner surface, which project radially toward the center of the gear ring. Alternatively, the gear ring may include a rotating wheel or sleeve that compensates for the eccentric movement of the cycloidal disk by means of an auxiliary gear, wheel, or roller. The cycloidal disk moves eccentrically about the inner surface of the gear ring, i.e., it moves about the inner surface of the gear ring in an oscillating motion. Preferably, the cycloidal disk includes a plurality of spur teeth that project radially outward and preferably interact with the pins of the gear ring. The number of spur teeth in the cycloidal ring is less than the number of pins in the gear ring. Therefore, the eccentric movement of the cycloidal disk within the gear ring causes the cycloidal disk to rotate. The cycloidal disk is shaped as a ring, which preferably includes the aforementioned spur teeth on its outer surface and an internal gear with gear teeth on its inner surface.

[0016] The term "gear" is not limited to pin or tooth mechanisms, but may instead include wheels with flat surfaces without pins or teeth. In this case, the disc and the gear ring may engage with each other solely through friction.

[0017] The cycloidal disk is driven to make eccentric movements by means of a planetary gear arranged between the cycloidal disk and the pinion. In this arrangement, the rotational movement of the drive shaft and the pinion in a first direction is converted into rotational movement of the planetary gear, and then into a second rotational movement, which is opposite to the first rotational movement. Note that when the planetary gear meshes with the internal gear of the cycloidal ring, the planetary gear itself moves about the pinion in the first direction. Therefore, the planetary gear experiences two movements simultaneously: first, it rotates about its central axis in a second direction, and second, it moves about the pinion in the second direction. This combined movement of the planetary gear drives the cycloidal disk to make the aforementioned eccentric movements.

[0018] Examples of drug delivery devices may include a disposable injection pen having a cartridge containing a liquid drug, a semi-disposable injection pen having a reusable drive unit and a replaceable container including a cartridge, a reusable injection pen having a replaceable cartridge, or an autoinjector having a syringe (particularly a semi-disposable autoinjector having a reusable drive unit and a replaceable container including a syringe).

[0019] In this context, the terms “substance,” “drug,” “pharmaceutical,” and “medicinal product” will be understood to include any flowable medical formulation suitable for controlled administration via a device such as a cannula or a needle, and to include liquids, solutions, gels, or fine suspensions containing one or more medically active ingredients. A pharmaceutical product may be a composition comprising a single active ingredient, or it may be a pre-mixed or co-formulated composition having more than one active ingredient present in a single container. Pharmaceutical products include drugs such as peptides (e.g., insulin, insulin-containing drugs, GLP-1-containing drugs, or derivatives or similar formulations), proteins and hormones, active ingredients derived from or harvested from biological sources, hormone- or gene-based active ingredients, nutritional formulations, enzymes, and other substances in both solid (suspension) and liquid forms, and also include polysaccharides, vaccines, DNA, RNA, oligonucleotides, antibodies, or portions of antibodies, and also include suitable basic, auxiliary, and carrier substances.

[0020] The term “distal” refers to the direction or end of a drug delivery device that carries the needle or cannula, while the term “proximal” refers to the opposite direction or end that points away from the needle or cannula.

[0021] The terms “injection system” or “syringe” refer to a device that is removed from the injection site after each drug event or drug delivery process, while the term “infusion system” refers to a device that has a cannula or needle that remains in the patient’s skin for an extended period of time (e.g., several hours).

[0022] Preferably, the drive mechanism is an electric motor, and more preferably a stepper motor. The use of a stepper motor allows for precise control of the driver without the need for control electronics or closed control loops. This enables the use of the driver to deliver controlled doses of medication via a drug delivery device in which the driver is used. Furthermore, stepper motors are readily available and inexpensive, significantly reducing the cost of the driver.

[0023] Alternatively, electric motors are servo motors or synchronous motors.

[0024] In a preferred embodiment, the drug delivery device is an electronic injection device that includes a drive mechanism with an electric motor. In this case, the motor drives the drive shaft to dispense the drug. The electronic injection pen is preferably pen-shaped. The electronic injection device preferably includes a drive member or clutch sleeve, wherein a cycloidal disk is rotatably coupled to the drive member or clutch sleeve, such that rotational movement of the cycloidal disk is transferred to the drive member or clutch sleeve.

[0025] Preferably, the pinion, cycloidal disc, gear ring, and / or planetary gear are made of polymer materials. Using polymer materials for these components allows them to be manufactured using injection molding. Therefore, mass production can be carried out quickly and inexpensively.

[0026] The polymer material is preferably a durable thermoplastic, such as polycarbonate (PC), polystyrene (PS), acrylonitrile butadiene styrene (ABS), poly(methyl methacrylate) (PMMA), polyoxymethylene (POM), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyimide (PI), polyetherimide (PEI), polysulfone (PS), polyvinylidene chloride (PVDC), polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or polyamide (PA). Preferably, the pinion, cycloidal disk, gear ring, and / or planetary gears are all made of the same polymer. However, alternatively, the pinion, cycloidal disk, gear ring, and / or planetary gears may be made of different polymers.

[0027] Preferably, the polymer material is a medical-grade polymer material, that is, a polymer material that meets the requirements of ISO 10993 and / or EU Regulation 2017 / 745.

[0028] Preferably, the planetary gear has helical teeth (curved teeth) arranged on its outer surface. Simultaneously, the pinion and the internal gear of the cycloidal disk have matching helical teeth. The use of helical teeth provides the advantage of smooth and quiet operation of the gear components.

[0029] Alternatively, planetary gears may include toothing.

[0030] Preferably, the planetary gear and cycloidal actuator are configured to provide a reduction gear ratio of at least 50:1, preferably at least 100:1, between the drive shaft and the cycloidal disk. This means that the cycloidal disk rotates one full revolution for at least 50, preferably at least 100 full revolutions of the pinion and drive shaft.

[0031] Preferably, the gear ring has an outer diameter that corresponds to or is smaller than the outer diameter of the housing of the drive mechanism (preferably an electric motor). Therefore, the drive mechanism is the largest component of the entire actuator; that is, the actuator according to the invention will be fitted into any drug delivery device with a sufficient diameter to receive the drive mechanism.

[0032] Preferably, the drive mechanism has a diameter of 10 mm or less. Therefore, it is possible to use the drive in small and convenient drug delivery devices.

[0033] The cycloidal disk preferably includes a cylindrical protrusion extending from the cycloidal disk in an axial direction opposite to that of the drive mechanism. This cylindrical protrusion can be used to connect the actuator to a further component of the drug delivery device in which the actuator is used. The protrusion preferably has a diameter equal to or smaller than the diameter of the cycloidal disk.

[0034] Preferably, the drive's gear ring is a rotating gear ring and includes an outer rotating sleeve and at least three auxiliary wheels or rollers circumferentially arranged inside the rotating sleeve. The auxiliary wheels or rollers mesh with the external gear of the cycloidal disk and are therefore radially arranged between the cycloidal disk and the outer rotating sleeve.

[0035] That means that as the roller follows the outer surface of the external gear (e.g., teeth) of the cycloidal disk, the cycloidal disk rotates the auxiliary roller through its eccentric movement. The rotating roller, in turn, rotates the outer rotating sleeve. The latter can be coupled to a clutch or drive mechanism to drive the piston rod of the drug delivery device.

[0036] Therefore, the auxiliary roller and outer rotating sleeve transform the eccentric movement of the cycloidal disc into pure rotational movement about the central axis or longitudinal axis of the drive and delivery device.

[0037] The outer rotating sleeve is rotatably connected to, for example, a drive member or clutch sleeve adapted to drive the piston rod in the distribution direction. Alternatively, the outer rotating sleeve is an integral part of the drive member or clutch sleeve.

[0038] This application also relates to a drug delivery device comprising a longitudinal housing and a plunger rod adapted to advance a piston within a reservoir containing a drug to dispense the drug. The plunger rod is driven in the dispensing direction by means of a actuator according to the invention to advance the piston.

[0039] The drug delivery device is preferably an injection device. After each administration of a dose of medication, the injection device is removed from the injection site. Alternatively, the drug delivery device can be an infusion device, i.e., a device having a cannula or needle that remains in the patient's skin for a period of time (e.g., several hours or days) to administer several doses of medication to the patient during that time period. However, more preferably, the drug delivery device is a pen-shaped injection device.

[0040] The housing is preferably elongated and has a circular, elliptical, rectangular, or polygonal cross-section. The dimensions and shape of the cross-section may vary along the central axis of the housing. Preferably, the housing is made of a polymer material, more preferably of a medical-grade polymer material, i.e., a polymer material that meets the requirements of ISO 10993 and / or EU Regulation 2017 / 745. The housing has a distal end and a proximal end. The distal end is the end of the housing that points toward the cannula or needle used to administer the medication to the patient and is connected to the drug delivery device. In the case of an injection device, the distal end of the housing will therefore point toward the patient's skin during an injection event. Therefore, the proximal end of the housing is the end of the housing that faces away from the needle or cannula. In the case of an injection device, the proximal end of the housing faces away from the patient's skin during an injection event.

[0041] The housing is preferably open at its proximal and distal ends to allow assembly of the drug delivery device. The proximal and distal ends are closed with suitable caps or the like to protect the components of the drug delivery device located within the housing.

[0042] The drug delivery device preferably includes a reservoir containing the drug. In some embodiments, the reservoir may be located within the housing. In this case, the drug delivery device is preferably discarded after all the drug in the reservoir has been administered to the user. However, preferably, the reservoir is included in a cartridge, which is preferably removably connected to the housing at the distal end of the housing.

[0043] The reservoir includes a piston that is movable to dispense medication via a cannula or needle. The cannula or needle is preferably connected to or can be connected to the distal end of the housing, cartridge, or reservoir.

[0044] The pharmaceutical preparation is preferably a preparation for treating diabetes. Preferably, the preparation is insulin or a derivative thereof.

[0045] The plunger rod moves linearly about a central axis via a actuator. By means of the plunger rod's movement, a piston moves within a reservoir to dispense medication. Therefore, the medication delivery device is an automated medication delivery device in which medication is dispensed upon the patient actuating a button, etc. The plunger rod is preferably arranged such that its length axis coincides with the central axis of the housing.

[0046] Since the output of the actuator is rotational movement, the drug delivery device includes means for converting the rotational movement of the actuator into linear movement of the plunger rod. In some preferred embodiments, in addition to linear movement, the plunger rod may also be additionally driven to rotate. Of course, this rotational movement of the plunger rod can be used to drive the plunger rod in a linear direction.

[0047] The drug delivery device preferably includes a dispensing button that a patient can press to dispense a dose of medication using the device. Preferably, the drug delivery device further includes a control element connected to the drive mechanism and the dispensing button to activate the drive mechanism for a defined time period when the dispensing button is pressed.

[0048] The drug delivery device preferably includes a dose-setting arrangement that allows setting the dose of the drug to be administered using the drug delivery device. The dose-setting arrangement preferably includes: a dose-setting wheel that can be rotated by the patient to adjust the dose; and an indicator, preferably a screen, that displays the set dose to the patient. The set dose is delivered by activating the device within a defined time, the defined time being calculated based on parameters of the reservoir's volume and / or diameter and the linear velocity of the plunger rod.

[0049] Furthermore, the drug delivery device preferably includes a dose counter that indicates the amount of drug that has been dispensed from or remains in the reservoir.

[0050] The housing includes an electrical energy source (such as a primary battery, secondary battery, or supercapacitor) to provide power to any electric drive mechanism that may be present.

[0051] Preferably, the cycloidal disk is rotatably coupled to a drive member, which is configured as a hollow cylinder concentrically arranged around a plunger rod. The plunger rod has threads on its outer circumference that engage with the drive member in a distal region. The plunger rod further includes at least one spline that engages with at least one locking pin to prevent rotation of the plunger rod.

[0052] This configuration provides a simple and reliable means of converting the rotational movement of the actuator into the linear movement of the plunger rod. The drive member itself does not move linearly about the housing, and therefore the connection between the cycloidal disk of the actuator and the drive member can remain simple. For example, the drive member can be connected to the cycloidal disk or a protrusion extending from the cycloidal disk by means of a form fit connection. Preferably, the connection between the cycloidal disk and the drive member is achieved by means of teeth on the inner surface of the proximal region of the drive member engaging with matching teeth on the outer surface of the protrusion extending from the cycloidal disk. When the cycloidal disk is driven to rotate eccentrically, the protrusion also moves eccentrically. Therefore, the diameter of the inner surface of the proximal region of the drive member is preferably chosen such that it is equal to the diameter of the outermost rotational path of the outer surface of the protrusion. Thus, the protrusion can rotate eccentrically in the proximal region of the drive member while still being in contact with it at a position where the teeth can engage with each other. Thus, the eccentric rotation of the protrusion and the cycloidal disk can be converted into the central rotation of the drive member by a simple but reliable means.

[0053] Rotation of the plunger rod is prevented by the engagement of the at least one locking pin with the at least one spline of the plunger rod. Since the plunger rod engages with the distal region of the drive member, the rotation of the drive member is converted into linear movement of the plunger rod when the drive member is driven to rotate.

[0054] Preferably, the drive component is arranged inside a retainer in the form of a hollow cylinder.

[0055] Alternatively, in the plunger rod rotation configuration, the plunger rod is threaded into the housing of the delivery device, and the plunger rod is rotatably splined and secured to the drive member. Therefore, during dose delivery, the plunger rod is screwed along the distal and dispensing directions.

[0056] That means that the cycloidal disk is preferably rotatably coupled to a drive member configured as a hollow cylinder concentrically arranged around a plunger rod, wherein the plunger rod is rotatably coupled to the drive member, and wherein the plunger rod has threads on its outer circumference that engage with the housing or housing insert of the drug delivery device.

[0057] The drug delivery device preferably includes a drive member, wherein a proximal portion of the drive member is rotatably coupled to or forms a cycloidal disk, and wherein the proximal portion moves freely eccentrically with the cycloidal disk, and wherein a distal portion of the drive member is rotatably guided.

[0058] This allows for easy design of the mechanism, as the proximal portion of the drive member does not need to be supported or guided and can move together with the cycloidal disk. In contrast, the distal portion of the drive member is preferably rotatably guided by the housing of the delivery device, and thus the distal portion is restricted to rotational movement.

[0059] The drug delivery device preferably includes a reset mechanism comprising a coupling member adapted to selectively engage a plunger rod to a drive member such that dispensing movement of the drive member is transferred to the plunger rod, and to disengage the plunger rod from the drive member such that movement of the drive member is not transferred to the plunger rod, and vice versa.

[0060] This provides a reset function because if the plunger rod separates from the drive component (e.g., during the replacement of an empty cartridge or reservoir in a drug delivery device), the plunger rod can be pulled back into the housing.

[0061] The connecting member can be an interlocking member, such as a toothed connector or a splined engagement member, which can be released to separate the plunger rod from the drive member.

[0062] Other advantageous embodiments and combinations of features can be derived from the following detailed description and throughout the claims. Attached Figure Description

[0063] The accompanying drawings, used to explain the embodiments, show:

[0064] Figure 1 This is an exploded view of an inventive actuator for a drug delivery device;

[0065] Figure 2 It is based on the fact that it is in an assembled state. Figure 1 A perspective view of the driver;

[0066] Figure 3 It is based on the planar diagram on its surface. Figure 1 The driver;

[0067] Figure 4 It is a perspective length section, which shows as follows Figure 1 The interaction between the driver and components of the drug delivery device shown;

[0068] Figure 5 It is a length cut through the drug delivery device with an inventive driver according to the invention;

[0069] Figure 6 This is a second embodiment of the driver in a plan view of its surface.

[0070] In the accompanying drawings, the same parts are given the same reference numerals. Detailed Implementation

[0071] Figure 1 An exploded view of an inventive actuator 1 for a drug delivery device is shown. The actuator 1 includes an electric motor 2, preferably a stepper motor. The electric motor 2 has a drive shaft 3 that is driven to rotate. A pinion 4 is arranged on the drive shaft 3. The pinion 4 has helical teeth (helical teeth) arranged on its outer circumference. In contrast to spur gears, the helical teeth provide smooth and quiet operation.

[0072] The electric motor 2 further includes an electrical connector 12 and a shoulder 13 surrounding the drive shaft 3.

[0073] A retaining gear ring 7 is arranged on the first surface of the electric motor 2. The retaining gear ring 7 includes a plurality of pins 11 on its inner surface, which protrude radially toward the center of the retaining gear ring 7. The retaining gear ring 7 is formed as a hollow cylinder with a radial disk 14 that closes a portion of the face of the retaining gear ring 7, thereby leaving a central opening sized to be positioned on the shoulder 13 of the electric motor 2. Therefore, the retaining gear ring 7 can be precisely positioned on the first surface of the electric motor 2.

[0074] Cycloidal disk 6 is arranged inside fixed gear ring 7. Cycloidal disk 6 includes spur teeth 10 on its outer circumference. Cycloidal disk 6 includes fewer spur teeth 10 than the number of pins 11 of fixed gear ring 7. The diameter of cycloidal disk 6 is smaller than the diameter of the inner surface of fixed gear ring 7. Therefore, cycloidal disk 6 can be eccentrically moved within fixed gear ring 7. Through this eccentric movement, the spur teeth 10 engage one after another with the pins 11 of fixed gear ring 7. Since the number of pins 11 is greater than the number of spur teeth 10, each of the spur teeth 10 is slightly offset relative to the opposite pin 11. Therefore, when one of the spur teeth 10 engages with the opposite pin 11, cycloidal disk 6 rotates about its axis.

[0075] To impart eccentric motion to the cycloidal disk 6, a planetary gear 5 is arranged between the pinion 4 and the cycloidal disk 6. The cycloidal disk 6 has an internal gear 9 with helical teeth that mesh with the helical teeth 8 of the planetary gear 5. The planetary gear 5 is sized such that the cycloidal disk 6 is pushed into contact with the fixed gear ring 7 at a position opposite to where the planetary gear 5 meshes with the internal gear 9.

[0076] As an example, the gears include a pinion 4 and a planetary gear 5 (each of which has 8 teeth), a cycloidal disk 6 with 23 teeth in the inner gear and 26 teeth in the outer gear, and a fixed gear ring 7 with 27 teeth, thereby producing a gear ratio of 103:1.

[0077] Figure 2 The assembly state is shown according to Figure 1 A perspective view of the actuator. As can be seen, the outer diameter of the fixed gear ring 7 corresponds to the outer diameter of the electric motor 2. Therefore, the actuator 1 forms a compact component that can be inserted into the housing of the drug delivery device. Figure 1 It can also be seen that the drive 1 according to the present invention includes only four additional parts besides the electric motor 2.

[0078] Figure 3 The plan view to its surface shows the following: Figure 1 The actuator. In this figure, it is readily apparent that the planetary gear 5 drives the cycloidal disk 6 to engage with the fixed gear ring 7, while the cycloidal disk 6 completely disengages from the fixed gear ring 7 at the side opposite to the planetary gear 5. Furthermore, the gradual offset of the spur teeth 10 of the cycloidal disk 6 relative to the pins 11 of the fixed gear ring 7 can be easily observed.

[0079] Figure 4 It is a perspective length section, which shows as follows Figure 1The interaction between the actuator and components of the drug delivery device is shown. The cycloidal disk 6 includes a protrusion 15 extending axially from a first surface of the cycloidal disk 6. The protrusion 15 has the form of a hollow cylinder, preferably concentric with the cycloidal disk 6. The protrusion 15 includes external teeth 17 on its outer surface, which mesh with the same number of internal teeth 18 on the inner surface of the proximal region of the drive member 16. The diameter of the inner surface of the proximal region of the drive member 16 is chosen such that it is equal to the diameter of the outermost rotational path of the outer surface of the protrusion 15, which is driven to perform eccentric rotational movement, because it is integral with the cycloidal disk 6. By means of this interaction, the eccentric rotational movement of the cycloidal disk 6 can be transformed into a central rotation of the drive member 16.

[0080] Alternatively, the drive member 16 may be integral with the cycloidal disk 6. In this case, a central bearing supports the distal end of the drive member, and the wall thickness and / or material properties of the drive member cause a certain radial flexibility at the proximal end of the drive member when transmitting torque from the position of the cycloidal disk 6 to the distal end. Further alternatively, the cycloidal disk 6 or the protrusion may engage a threaded rod, which in turn drives a hollow plunger rod having an internally threaded section at its proximal end.

[0081] The drive member 16 is configured as a hollow cylinder arranged around a plunger rod 19. The plunger rod 19 includes an external thread 20. The external thread 20 engages with a distal region of the drive member 16. The plunger rod 19 further includes a spline 22 extending in an axial direction. A pin disposed at the distal end 23 of a retainer 24 engages with the spline 22. This pin is part of the retainer 24, which is shaped to surround the hollow cylinder of the drive member 16. The engagement of the pin within the spline 22 prevents rotation of the plunger rod 19. Thus, when the drive member 16 is driven to rotate, the plunger rod 19 moves linearly by means of the engagement of the external thread 20 with the distal region of the drive member 16. At its distal end, the plunger rod 19 includes a flange 21. The flange 21 actuates a piston in the reservoir of the delivery device to dispense a dose of medication.

[0082] Figure 5 The length of the drug delivery device 30, which has an inventive actuator 1 according to the invention, is cut through. The drug delivery device 30 includes a longitudinal housing 31 having a circular cross-section. The actuator 1 is inserted into the housing from its distal end. Further, a dispensing button 37 is arranged on the distal end of the housing 31. By pressing the dispensing button 37, a predetermined dose of medication is dispensed from the drug delivery device 30. The dispensing button 37 and the electric motor 2 of the actuator are connected to a control element 38. The control element 38 activates the electric motor 2 of the actuator 1 for a preset time, thereby dispensing the predetermined dose of medication. A battery 36 is arranged within the housing to supply power to the control element 38 and the electric motor 2 of the actuator 1. Further, a retainer 24 having a plunger rod 19 is arranged within the housing 31.

[0083] A cartridge 32, having a reservoir 33 filled with medication, is connected to the proximal end of a housing 31. At its distal end, the reservoir 33 includes a connector 39 for connecting a needle or cannula to the reservoir 33 to inject medication into a patient's tissue. A piston 34 is disposed within the reservoir 33, within which it can move linearly to displace medication through the connector 39. To allow the piston 34 to move within the reservoir 33, the piston 34 contacts a flange 21 disposed on the distal end of a plunger rod 19. The cartridge 33 includes a removable cap 39 that encloses the cartridge at its distal end.

[0084] Figure 6 A second embodiment of the drive is depicted in plan view. The drive is similar to the first embodiment and includes a planetary gear 5 that drives as described above. Figures 1 to 5 The described cycloidal disc 6.

[0085] However, in contrast to the first embodiment, such as Figure 6 The driver shown according to the second embodiment includes a rotating gear ring 50, which includes a plurality of cylindrical rollers 52 and an outer rotating sleeve 51.

[0086] Rollers 52 are radially arranged on the outer side of the cycloidal disk 6 and the inner side of the outer rotating sleeve 51. The diameter of the cycloidal disk 6 is smaller than the inner diameter of the rotating sleeve 51. Therefore, the cycloidal disk 6 can be eccentrically moved within the rotating sleeve 51. Through this eccentric movement, the spur teeth 10 of the cycloidal disk 6 roll over the rollers 51 one after another. Since the number of rollers 52 is greater than the number of spur teeth 10, each of the spur teeth 10 is slightly offset relative to the opposing roller 52. Therefore, when one of the spur teeth 10 rolls over the opposing roller 52, the cycloidal disk 6 rotates about its axis. Through this movement, the engaged rollers 52 are able to rotate about their axis of rotation. Since the rollers 52 then engage the inner surface of the rotating sleeve 51, the rotating rollers 52 cause the sleeve 51 to rotate. The sleeve 51 is rotatably guided inside the housing 53 and can be connected to the drive components of a drug delivery device, such as those described above. Figure 5 As described.

[0087] Alternatively, the first or second embodiment of the actuator may be implemented in a reusable delivery device that includes a reset mechanism to reset the piston rod during cartridge or reservoir replacement.

[0088] List of reference numerals

[0089] 1 drive

[0090] 2 electric motors

[0091] 3 drive shafts

[0092] 4 small gears

[0093] 5 planetary gears

[0094] 6 cycloidal reels

[0095] 7 Fixed gear ring

[0096] 8 helical teeth

[0097] 9 internal gears

[0098] 10 straight teeth

[0099] 11 sales

[0100] 12 electrical connectors

[0101] 13 Shoulders

[0102] 14 radial discs

[0103] 15 protrusions

[0104] 16 driving components

[0105] 17 external teeth

[0106] 18 internal teeth

[0107] 19-piston rod

[0108] 20 external thread

[0109] 21 flange

[0110] 22 splines

[0111] 23 remote

[0112] 24 retainer

[0113] 30 drug delivery devices

[0114] 31 shell

[0115] 32 cartridges

[0116] 33 storage

[0117] 34 pistons

[0118] 35 hats

[0119] 36 batteries

[0120] 37 Assignment Buttons

[0121] 38 control elements

[0122] 39 connector

[0123] 50 rotary gear ring

[0124] 51 External Rotary Sleeve

[0125] 52 auxiliary rollers

[0126] 53. Outer shell.

Claims

1. A driver (1) for a drug delivery device, the driver comprising a drive mechanism having a drive shaft (3), a pinion (4) arranged on the drive shaft (3), and a cycloidal driver having a cycloidal disk (6) and a gear ring (7, 50), characterized in that, The cycloidal disk (6) is driven to perform eccentric motion by means of a single planetary gear (5), which meshes with the pinion (4) on the drive shaft (3) and with the internal gear of the cycloidal disk (6). The cycloidal disk (6) includes a cylindrical protrusion (15) extending from the cycloidal disk in an axial direction away from the drive mechanism. The cylindrical protrusion (15) includes external teeth (17) on its outer surface, which engage with internal teeth on the inner surface of a further component of the drug delivery device.

2. The driver (1) according to claim 1, characterized in that, The driving mechanism is an electric motor (2).

3. The driver (1) according to claim 2, characterized in that, The driving mechanism is a stepper motor.

4. The driver (1) according to any one of claims 1 or 2, characterized in that, The pinion (4), the cycloidal disk (6), the gear ring (7) and / or the planetary gear (5) are made of polymer material.

5. The driver (1) according to any one of claims 1 to 2, characterized in that, The planetary gear (5) has helical teeth arranged on its outer surface.

6. The driver (1) according to any one of claims 1 to 2, characterized in that, The planetary gear (5) and the cycloidal driver are configured to provide a reduction gear ratio of at least 50:1 between the drive shaft (3) and the cycloidal disk (6).

7. The driver (1) according to claim 6, characterized in that, The planetary gear (5) and the cycloidal drive are configured to provide a reduction gear ratio of at least 100:1 between the drive shaft (3) and the cycloidal disk (6).

8. The driver (1) according to any one of claims 1 to 2, characterized in that, The fixed gear ring (7) has an outer diameter that corresponds to or is smaller than the outer diameter of the drive mechanism.

9. The driver (1) according to claim 2, characterized in that, The electric motor (2) has a diameter of 10 mm or less.

10. The driver (1) according to any one of claims 1 to 2, characterized in that, The cylindrical protrusion (15) is concentric with the cycloidal disk (6).

11. The driver (1) according to any one of claims 1 to 2, characterized in that, The gear ring (50) is rotatable and includes an outer rotating sleeve (51) and at least three auxiliary rollers (52) arranged circumferentially on the inner side of the outer rotating sleeve (51) and meshing with the outer gear of the cycloidal disk (6).

12. A drug delivery device comprising a longitudinal housing (31) and a plunger rod (19) adapted to advance a piston (34) within a reservoir (33) containing a drug to dispense the drug, the plunger rod (19) being driven in a dispensing direction by means of a driver to advance the piston (34), the driver comprising a drive mechanism having a drive shaft (3), a pinion (4) arranged on the drive shaft (3), and a cycloidal driver having a cycloidal disk (6) and a gear ring (7, 50), characterized in that, The cycloidal disk (6) is driven to make an eccentric motion by means of a single planetary gear (5), which meshes with the pinion (4) on the drive shaft (3) and with the internal gear of the cycloidal disk (6).

13. The drug delivery device according to claim 12, characterized in that, The cycloidal disk (6) is rotatably connected to a drive member (16), which is configured as a hollow cylinder concentrically arranged around the plunger rod (19), the plunger rod (19) having threads on its outer circumference, the threads engaging with the drive member in the distal region of the drive member (16), wherein the plunger rod (19) includes at least one spline, the at least one spline engaging with at least one locking pin to prevent rotation of the plunger rod (19).

14. The drug delivery device according to claim 12, characterized in that, The cycloidal disc (6) is rotatably connected to the drive member (16), which is configured as a hollow cylinder concentrically arranged around the plunger rod (19), wherein the plunger rod (19) is rotatably connected to the drive member (16), wherein the plunger rod (19) has threads on its outer circumference, the threads engaging with the housing (31) of the drug delivery device or an insert of the housing (31).

15. The drug delivery device according to any one of claims 13 to 14, wherein, The proximal portion of the drive member (16) is rotatably connected to or forms the cycloidal disk (6), and wherein the proximal portion moves freely eccentrically with the cycloidal disk (6), and wherein the distal portion of the drive member (16) is rotatably guided.

16. The drug delivery device according to any one of claims 13 to 14, characterized in that, The reset mechanism includes a coupling member adapted to selectively connect the plunger rod (19) to the drive member (16) such that distributive movement of the drive member (16) is transferred to the plunger rod (19), and to disengage the plunger rod (19) from the drive member (16) such that movement of the drive member (16) is not transferred to the plunger rod (19), and vice versa.

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