BR112020016503B1 - DRIVE SYSTEM AND DRIVE METHOD FOR INSULIN PUMPS - Google Patents

Abstract

A drive system (112) for insulin pumps (110) is described. The drive system (112) comprises: - a motor (120) configured to rotate at a previously determined revolution speed; - a gearbox (122) for converting the rotation of the motor (120) into continuous linear movement of the piston (124), wherein the continuous linear movement of the piston (124) determines the basic rate of insulin delivery; and - a mechanical displacement unit (126) configured to override the continuous linear movement of the piston (124) by mechanically displacing the piston (124) independent of the basic rate. Furthermore, an insulin pump (110) and a method of driving insulin pumps (110) are described.

Description

FIELD OF INVENTION

[001] The present invention relates to a drive system for insulin pumps, insulin pumps comprising the drive system and method of driving insulin pumps. The method and devices according to the present invention can be mainly used for supplying insulin to users. The present invention can be applied in the field of home care and also in the field of professional care, such as in hospitals. Other applications are generally feasible.

BACKGROUND OF THE INVENTION

[002] The delivery of medication to users, specifically the delivery of insulin, plays an important role in the prevention and treatment of diseases, particularly in the treatment of diabetes mellitus. In addition to the use of injection pens or syringes, the delivery of insulin can specifically be accomplished using insulin pumps.

[003] Generally, electronically or electromechanically driven pumps require complex electronic components for control and monitoring. Such pumps are generally prone to malfunction or failure due to failure of electronic or electromechanical components. Specifically, in the field of drug delivery, such as insulin, accurate delivery and control of drug quantity are critical. Consequently, error-resistant insulin pumps that operate without electronic control are desirable. Although mechanical pumps that operate without electronic control are generally known in the prior art and despite the advantages of prior art pumps for insulin delivery, several technical challenges remain.

[004] In particular, it is usually necessary for the user to wear the insulin pump on his/her body at all times, in order to generate a preferably small and compact construction of the insulin pump and its components. Common pumps for delivering medication, such as insulin, comprise a series of medication reservoirs. Fluid delivery devices are described, for example, in WO 2011/046950 A1. The fluid delivery device comprises a housing containing a fluid reservoir. A needle is in fluid communication with the fluid reservoir in the engaged position and out of fluid communication with the fluid reservoir in the armed and storage positions. A proximal end of a biasing member is coupled to the housing and a distal end of the biasing member is configured to provide force to the fluid reservoir. A piston member extends through the biasing member and is coupled to the distal end of the biasing member. The piston member is fixed relative to the housing in the locked position so that the guiding member does not supply the force to the fluid reservoir, and the piston member is movable relative to the housing in the released position so that the guiding member supplies the force to the fluid reservoir. Transition of the needle from the stowed position to the armed position realizes transition of the piston from the locked position to the released position.

[005] WO 2007/108969 describes a disposable infusion device comprising a base arranged to adhere to the patient's skin, a cannula arranged to extend from the base to below the patient's skin to deliver a liquid medicament to the patient, and a source arranged to deliver the cannula with a liquid medicament. The device further includes an actuator that actuates the source to deliver the liquid medicament to the cannula. The source is arranged to deliver, with each actuation, a fixed volume of medicament to the cannula. A control sets the fixed volume.

[006] US 2003/009133 A1 describes a pump system for an infusion system that includes a linear drive that minimizes the space occupied by the pump components in a portable shelter. A motor and a motor drive shaft are arranged parallel to and adjacent to a syringe and a lead screw. A gearbox connects the drive shaft and the lead screw to transfer rotational motions between them. A piston drive member, such as a cone or drive nut, converts the rotary motion of the lead screw into linear motion of a syringe piston. Sensors detect when the piston or cone is in the “home” position and “end” position, respectively. Optionally, a proximity sensor is used to ensure that the cone and piston are in contact with each other during release. Alternatively, a clamping member selectively secures the lead screw against linear motion in at least one release direction.

[007] WO 2015/104412 A1 describes a transmission comprising a first gear wheel and a second gear wheel with a threaded hole and a threaded rod arranged non-rotatingly in threaded engagement with the threaded hole, such that rotation of the second gear wheel provides axial movement of the rod. The first and second gear wheels are arranged in a common plane and in rotatable engagement with each other, wherein the combined second gear wheel and rod are arranged on pivot corresponding to a center point defined by the intersection between the rod axis and the common plane, such that the rod, with the gear wheels engaged, can be arranged out of alignment with the first gear wheel axis.

[008] US 2012/179112 A1 describes a drug delivery device comprising a housing for holding a drug cartridge, a piston rod and a driver. The drug cartridge has a drug outlet and a bung axially movable along the drug cartridge for releasing a drug, the piston rod has a plunger for moving the bung and a forward member telescopically coupled to the plunger which can be directed by the driver to extend or retract the piston rod. Further, the device comprises a linkage coupled between the plunger and a fixture and a drive member telescopically coupled to the forward member. The driver is operative to rotate the drive member to telescopically move the forward member relative to the drive member so that the plunger is moved relative to the forward member by means of the linkage.

[009] EP 1,195,172 A2 describes an automatic injection device having piston supports supporting cylinder pistons and a plurality of head systems having a drive mechanism for moving the piston supports forward and backward so that the device can support a plurality of syringes and operate the injection or suction in each syringe independently. This device also contains a mechanism for prohibiting the backward movement of the piston support of a second head when the piston support of a first head is moving forward and the piston support of the second head is stationary. This structure effectively prevents the liquid from being undesirably mixed and its injection quantity becoming less accurate.

[0010] US 2018/055995 A1 describes a controlled delivery drive mechanism that includes a drive housing, piston, and a biasing member initially retained in an energized state and is configured to rest on an interface surface of the piston. The piston is configured for translation of a plunger seal and a cylinder. A tie rod is connected between the piston and the winch drum to restrict free expansion of the biasing member and free axial translation of the piston upon which the biasing member rests. The drive mechanism may further include a gear assembly and an escapement regulation mechanism configured to control rotation of the gear assembly to release the tie rod from the winch drum. Metering of the tie rod by the escapement regulation mechanism controls the rate or profile of medication delivery to the user.

[0011] Furthermore, common drug delivery pumps, such as insulin pumps, comprise a series of flow or fluid paths in order to deliver a base rate, such as a base or background amount of insulin, as well as a metered dose rate, such as an extra or additional amount of insulin. Flow or fluid paths are generally susceptible to obstructions, leading to limitation of the amount of insulin delivered or even total failure of insulin delivery. As an example, US 6,283,944 B1 describes a pump having a shield that is equipped with the first and second fluid paths from the pump reservoir to a single outlet port. Furthermore, an infusion system is described that delivers medication to patients at a fixed rate, while allowing the patient to introduce a controlled dosage when needed. Additionally, WO 2009/045776 A2 describes a wearable infusion device comprising a first control movable between a first position and a second position which, when in the first position, establishes a first fluid path between a reservoir and a pump and, in the second position, establishes a second fluid path between the pump and an outlet. The second control actuates the pump only when the second fluid path has been established by the first control.

[0012] Problem to be solved: It is therefore desirable to provide methods and devices that meet the above-mentioned technical challenges. Specifically, a drive system, an insulin pump and a method will be provided that provide a high degree of accuracy and reliability of insulin delivery, while allowing for small and compact construction.

DESCRIPTION OF THE INVENTION

[0013] This problem is addressed by a drive system for driving an insulin pump, an insulin pump for delivering insulin to users, and a method of driving insulin pumps having the features of the independent claims. Suitable embodiments which may be carried out in isolation or in any arbitrary combinations are listed in the dependent claims.

[0014] As used below, the terms “possess”, “comprise”, “include” or any of their arbitrary grammatical variations are used non-exclusively. These terms may therefore designate a situation in which, in addition to the characteristic introduced by these terms, no additional characteristic is present in the entity described in this context and a situation in which one or more additional characteristics are present. The expressions “A possesses B”, “A comprises B” and “A includes B”, for example, may designate a situation in which, in addition to B, no other element is present in A (i.e., a situation in which A consists solely and exclusively of B) and a situation in which, in addition to B, one or more additional elements are present in the entity A, such as element C, elements C and D or even other elements.

[0015] Furthermore, it should be noted that the expressions “at least one”, “one or more” or similar expressions indicating that a feature or element may be present one or more times will typically be used only once when introducing the corresponding feature or element. In most cases below, when referring to the corresponding feature or element, the expressions “at least one” or “one or more” will not be repeated, even if the corresponding feature or element is present one or more times.

[0016] Additionally, as used below, the expressions “preferably”, “most preferably”, “particularly”, “more particularly”, “specifically”, “most specifically” or similar are used in conjunction with optional features, without restricting alternative possibilities. Features introduced by these expressions are therefore optional features and are not intended to restrict the scope of the claims in any way. The present invention, as those skilled in the art will recognize, may be embodied using alternative features. Similarly, features introduced by “in an embodiment of the present invention” or similar expressions are intended to be optional features, without restrictions with respect to alternative embodiments of the present invention, without restrictions with respect to the scope of the present invention and without restrictions with respect to the possibility of combining the features introduced in this way with other optional or non-optional features of the present invention.

[0017] In a first embodiment of the present invention, a drive system for driving an insulin pump is described. The expression “drive system”, as used herein, is a broad expression and should be given its common and customary meaning to those skilled in the art, without being limited to special or specific meanings. The expression may specifically indicate, without limitation, an arbitrary system configured to provide forward motion by exerting a force. In particular, the drive system may define and/or maintain a flow of insulin in motion. The drive system may be specifically configured to drive the insulin pump. The expression “insulin pump”, as used herein, is a broad expression and should be given its common and customary meaning to those skilled in the art, without being limited to special or specific meanings. The expression may specifically indicate, without limitation, a device for administering insulin from at least one insulin reservoir to a user.

[0018] The drive system comprises:- a motor configured to rotate at a previously determined revolution speed;- a gearbox for converting the motor rotation into continuous linear movement of the piston, wherein the continuous linear movement of the piston determines the basic rate of insulin delivery; and- a mechanical displacement unit configured to override the continuous linear movement of the piston by mechanical displacement of the piston independent of the basic rate.

[0019] The term “motor”, as used herein, is a broad term and should be given its common and customary meaning for those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary motor, machine or device configured to transform energy into kinetic energy or motion, for example, to transform mechanical energy, electrical energy or chemical energy into kinetic energy or motion of a device. The motor may therefore be or comprise a mechanical motor or electromechanical motor. In particular, the motor may transform energy into rotation or rotary motion of at least a part of the motor itself. Preferably, the motor may be configured to transform energy from a power source, such as an external power source, into rotary motion. In particular, the motor may be, for example, a physical or electrical power motor, such as an electric motor, pneumatic motor, hydraulic motor, time motor or the like. The speed, specifically the speed of revolution of the engine rotation, may, for example, be predetermined by the engine, such as by the construction or structure of the engine itself, or by the amount or level of power supplied to the engine.

[0020] The term “energy”, as used herein, is a broad term and should be given its common and customary meaning for those skilled in the art, without being limited to special or specific meanings. The term may specifically designate, without limitation, an arbitrary form of power supplied to the motor. In particular, the energy may be electrical energy, kinetic energy, potential energy or the like. The energy may be supplied, for example, in the form of electric current, one or more elastic elements, such as springs or elastic bands, compressed gas or in the form of pressurized fluid.

[0021] The engine rotation is converted into the continuous linear movement of the piston by the gearbox. The expression “gearbox”, as used herein, is a broad expression and should be given its common and customary meaning for those skilled in the art, without being limited to special or specific meanings. The expression may specifically indicate, without limitation, a mechanical device or system configured to modify or convert the speed, direction and/or force of movement, such as speed, torque, direction and/or force of linear or rotary movement. In particular, the gearbox may convert the speed, torque, direction and/or force of movement, using a series of transmission elements, such as gears, wheels, levers, belts, toothed racks or any other elements configured to transmit movement. In particular, the gearbox may comprise an arbitrary combination of these transmission elements, in order to convert the movement according to the needs. In particular, the gearbox is configured to convert the engine rotation into the continuous linear movement of the piston. Specifically, the gearbox can be configured to act on the piston, such as the piston in an insulin pump.

[0022] The expression “continuous linear motion” as used herein is a broad expression and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The expression may specifically indicate, without limitation, uninterrupted motion in an arbitrary direction along an axis, wherein the axis may specifically differ from a linear axis by not more than 20%, preferably not more than 10% and most preferably not more than 5%. Uninterrupted motion may occur, for example, at constant speed, such as a speed that deviates from the mean value by not more than 20%, preferably not more than 10% and most preferably not more than 5%. It should be noted, however, that motions at variable speed are also possible.

[0023] The term “piston” as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary movable element whose movement carries out or produces the movement of a fluid, specifically insulin, wherein the fluid may be in direct or indirect contact with the piston. The piston may, for example, be or comprise a plunger. In particular, the piston may, for example, be or comprise a movable wall or surface, such as the front surface or front wall of a plunger, in particular a movable wall of a containment, such as a cartridge or case. The piston may preferably be configured to displace the contents of the containment, such as insulin, preferably if the piston is moved. In particular, the piston may be movable within a cartridge or case configured to retain the fluid, such as insulin. The movement of the piston may specifically extrude the fluid, such as insulin, from the cartridge or case. As an example, the movement of the piston may generate extrusion of insulin from an insulin reservoir. Preferably, the piston may be or comprise at least one material that provides a movable seal between the piston and the cartridge, specifically between the piston and a wall of the cartridge, such as a flexible material. The piston may, for example, be or comprise at least one elastomeric material, such as any type of rubber or thermoplastic elastomer. There may, however, be different types of piston material. The piston may be particularly configured to perform continuous linear movement, wherein the continuous linear movement of the piston determines the basic rate of insulin delivery.

[0024] The term “base rate” as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, a fundamental quantity or volume, or a fundamental or previously determined volume flow rate of fluid, specifically insulin. Specifically, the base rate of insulin may be the minimum quantity or volume flow rate of insulin essential or fundamental for the control of cellular glucose and amino acid uptake in human or animal bodies. The base rate of insulin may, for example, regulate the blood glucose level caused by glucose emission from the liver in human or animal bodies.

[0025] Furthermore, the mechanical displacement unit is configured to override the continuous linear movement of the piston by the mechanical displacement of the piston independent of the base rate. Specifically, the continuous linear movement of the piston that determines the base rate of insulin delivery may be overridden by the mechanical displacement of the piston. The term “mechanical displacement unit,” as used herein, is a broad term and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary device configured to perform or operate, directly or indirectly, mechanical displacement of objects or elements. The term “mechanical displacement,” as used herein, is a broad term and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically designate, without limitation, physical alteration or adjustment of the position of objects or elements. In particular, mechanical displacement of the piston independent of the base rate may be performed by the mechanical displacement unit. Specifically, the continuous linear movement of the piston that determines the basic rate of insulin delivery may be overridden by mechanical displacement. Preferably, the movement of the piston to extrude the basic rate may be performed manually. Alternatively or additionally, the movement of the piston to extrude the basic rate may be performed hydraulically, using, for example, a hydraulic fluid to exert pressure on the piston.

[0026] The term “superimposed” as used herein is a broad term and should be given its common and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, the process of adding or forming layers, specifically adding one motion to another or superimposing a first motion with at least one second motion. In particular, if the continuous linear motion of the piston is superimposed by the mechanical displacement of the piston, the piston may perform the mechanical displacement in addition to the continuous linear motion. In particular, the piston continues its continuous linear motion while additionally performing the mechanical displacement.

[0027] Furthermore, the mechanical displacement of the piston, regardless of the base rate, can define the delivery of a metered dose of insulin. In particular, the mechanical displacement of the piston can specifically extrude the metered dose of insulin from the cartridge or cassette. As an example, the mechanical displacement of the piston can generate extrusion of the metered dose of insulin from an insulin reservoir. The expression “metered dose”, as used herein, is a broad expression and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The expression can specifically indicate, without limitation, a discrete dosage or quantity of fluid. Specifically, the metered dose of insulin can be the amount of insulin essential for the control of cellular glucose and amino acid absorption in human or animal bodies after a meal. The metered dose of insulin can, for example, regulate the blood glucose level caused by the ingestion of a meal in human or animal bodies.

[0028] The drive system may further comprise at least one energy source. The energy source may be specifically designed to store and release an amount of energy, such as electrical or mechanical energy. The energy source may be specifically configured to supply energy to the motor. As indicated above, the energy may be electrical energy, kinetic energy, potential energy or the like. The energy source may therefore be in particular an arbitrary device configured to supply energy in the form of electrical current, one or more elastic elements, such as springs or elastic bands, compressed gas or in the form of pressurized fluid, specifically to the motor. Furthermore, the energy source may be configured to store a previously defined amount of said energy. Preferably, the at least one energy source may comprise at least one electrical energy source. Specifically, the electrical energy source comprised by the energy source may be or comprise at least one of a battery or accumulator.

[0029] As indicated above, the motor may be, for example, a physical or electrically powered motor. Specifically, the motor may comprise at least one motor selected from the group consisting of an electric motor and a timing motor, preferably a spring-driven timing motor.

[0030] Furthermore, the piston may be mechanically coupled to a threaded rod. The expression “threaded rod”, as used herein, is a broad expression and should be given its ordinary and customary meaning for those skilled in the art, without being limited to special or specific meanings. The expression may specifically indicate, without limitation, an arbitrary elongated element wholly or partially spirally grooved. In particular, the threaded rod may be a shaft or rod having at least one spiral groove around an axis of the threaded rod. In particular, the threaded rod may be a long thread-shaped element having two ends. Preferably, the threaded rod may comprise a solid material. The threaded rod may, for example, be made of plastic material, metal material or metal alloy material, or one of their combinations. In particular, the piston may be mechanically coupled to at least one end of the threaded rod. The piston may, for example, be mechanically coupled to at least one end of the threaded rod by full contact, such as a physical contact that allows the piston to be pushed forward. Alternatively or additionally, the piston may be mechanically coupled to the threaded rod by means of a push-pull coupling, such as a push-pull coupling that provides fixed physical contact, preferably a push-pull coupling capable of preventing the piston from losing contact with the rod. The piston may, for example, be threaded onto the threaded rod and, in particular, one end of the threaded rod may be inserted into the piston by means of rotation of the threaded rod with respect to the piston. Other options or mechanisms for mechanically coupling the piston to the threaded rod are feasible, such as a bayonet coupling or a plug connection. In particular, the movement of the piston may be controlled by means of axial movement of the threaded rod.

[0031] The mechanical coupling of the piston to the threaded rod may be specifically configured to transmit motion from one to the other. Specifically, the piston and the threaded rod may be mechanically coupled such that the motion of the threaded rod generates motion of the piston or vice versa. In particular, the continuous linear motion of the piston may be the same as the continuous linear motion of the threaded rod. In particular, the motion of the threaded rod may be transferred directly to the piston. The motion of the threaded rod, such as continuous linear motion of the threaded rod, may therefore cause the piston to perform the same motion, such as the same continuous linear motion, of the threaded rod or vice versa. In particular, the gearbox may, for example, convert engine rotation into continuous linear motion of the piston by means of the threaded rod.

[0032] Alternatively or additionally, the mechanical coupling of the piston and the threaded rod may be configured such that the mechanical displacement of the piston may be equal to the mechanical displacement of the threaded rod. Specifically, mechanical displacement of the threaded rod may generate mechanical displacement of the piston. In particular, the mechanical displacement unit may be configured, for example, to act on the piston by overriding the continuous linear movement of the piston by the mechanical displacement of the threaded rod.

[0033] In particular, the threaded rod may preferably have a thread, such as a metric thread or a fine thread. In particular, the thread may have a thread pitch or inclination ranging from 0.1 mm to 1.5 mm, preferably ranging from 0.3 mm to 1 mm, and most preferably from 0.5 mm to 0.8 mm. As an example, the inclination of the threaded rod may correspond to a cross-sectional area of the piston. Specifically, the inclination of the threaded rod may correspond to the cross-sectional area of the piston, so that by moving the threaded rod through one turn of the thread, a specific amount of insulin, such as the amount of insulin representing the measured dosage, may be displaced, for example extruded, from the cartridge. As indicated above, the movement of the piston may depend on the movement of the threaded rod. As an example, movement of the piston by 0.7 mm along the axis of the threaded rod may generate, for example, extrusion or delivery of 5 IU.

[0034] Furthermore, the motor may be coupled to the threaded rod by means of at least one gear. In particular, the gear may be comprised of the gearbox. In particular, the rotation of the motor may be transmitted to the threaded rod by means of the gear. The gear may additionally be mounted concentrically around the threaded rod. In particular, the gear may be mounted concentrically around the axis of the threaded rod. The term “gear” as used herein is a broad term and should be given its common and customary meaning for those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary object configured for transmitting motion by means of rotation around an axis. The gear may be, for example, a toothed wheel, worm gear, friction wheel or the like. The gear may be particularly configured to transmit motion using various transfer mechanisms, such as traction or positive locking, for example, by means of interlocking teeth or interlocking.

[0035] The threaded rod may in particular be secured against rotation around its axis. Preferably, the threaded rod may be secured against rotation around its axis by at least one of a screw or switch. The screw or switch may be arranged, for example, so as to prevent rotation of the threaded rod. The screw or switch may, for example, be mounted transversely to the axis of the threaded rod.

[0036] Furthermore, the gear may be mounted to the threaded rod by means of a coupling. In particular, the coupling may have at least two engagement elements capable of engaging with the threaded rod in at least two axially displaced engagement positions.

[0037] In particular, each of the engaging elements may comprise at least one ratchet. In particular, the ratchet may be configured to provide, control and/or prevent movement of the engaging element in at least one direction. The engaging elements, with their corresponding ratchets, may specifically form a double ratchet arrangement. The expression “double ratchet arrangement”, as used herein, is a broad expression and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The expression may specifically indicate, without limitation, an arbitrary system of two or more ratchets configured to engage with another element, such as with the threaded rod, wherein at least one of the at least two ratchets is always engaged with the other element, such as the threaded rod.

[0038] Furthermore, each of the engagement elements may comprise a rigid base surrounding the threaded rod. Specifically, the rigid base may be, for example, ring-shaped and disposed around the threaded rod, for example to encircle the threaded rod. Furthermore, each of the engagement elements may comprise ratchet arms extending in an axial direction from the rigid base. The ratchet arms may be specifically configured to engage with at least one thread of the threaded rod. Preferably, the ratchet arms configured to engage with the thread may provide, control and/or prevent movement of the engagement elements. Specifically, the ratchet arms may extend from the rigid base toward the piston.

[0039] Furthermore, the engagement elements may be mounted on the threaded rod in such a way that the engagement elements may be switchable relative to one another. In particular, the engagement elements may be movable relative to one another along the axis of the threaded rod. In particular, the engagement elements may be switchable, for example, so that the distance between the at least two axially displaced engagement positions of the engagement elements may be varied or changed.

[0040] Preferably, the locking elements can be connected by means of at least two support rods. In particular, at least one of the locking elements can be mounted on the support rods in an axially switchable manner. Preferably, the at least two support rods can connect the locking elements in such a way that the locking elements can be movable relative to each other along the axis of the threaded rod. The movement of the locking elements can, for example, be oriented along the support rods, in particular along the axis of the threaded rod.

[0041] Furthermore, the snap-in elements may be connected by means of at least one axially acting spring element. Specifically, the snap-in elements may be connected by means of at least one axially acting spring element, such as an axially extending spring element. In particular, the spring element may connect the snap-in elements. The spring element may be specifically arranged such that the spring element surrounds at least one of the support rods. Preferably, the snap-in elements may be connected by means of two axially acting spring elements, wherein each spring element may surround at least one of the two support rods.

[0042] The locking elements may be connected in a rotationally fixed manner. In particular, the locking elements may be connected in such a way that the rotational movement of one of the locking elements, in particular rotation around the axis of the threaded rod, generates a similar rotary movement of the other locking element. Preferably, one locking element may not be capable of rotating relative to the other locking element. The locking elements may, for example, be connected in a rotationally fixed manner by means of the at least two support rods.

[0043] Furthermore, the coupling may comprise at least three coupling states. In particular, at least three coupling states may be adoptable by the coupling. The three coupling states may be in particular:- first state, in which, in the first state, the two engagement elements may engage with the threaded rod; in addition, the threaded rod may be driven in an axial direction specifically by means of rotation of the gear around an axis of the threaded rod; in particular, in the first state, the engagement elements may be located at fixed spatial separation from each other;- second state, in which, in the second state, the first engagement of the engagement elements may engage with the threaded rod and the second engagement of the engagement elements may disengage from the threaded rod; in particular, the first engagement element may push the threaded rod through the second engagement element in the first axial direction towards the piston; and- third state, in which the first engagement element can disengage from the threaded rod and the second engagement element can engage with the threaded rod; in particular, in the third state, the first engagement element can be pushed back in a second axial direction opposite to the first axial direction.

[0044] In the first state, for example, the mating elements may have a fixed axial separation. Specifically, there may be a fixed axial separation, such as a previously defined distance, between the mating elements in the first state, particularly in the first state adoptable by the coupling.

[0045] In particular, mechanical displacement of the piston independent of the base rate can be realized in the second state. Specifically, as indicated above, the piston can be mechanically coupled to the threaded rod. The threaded rod that is pushed through the second engagement element can therefore generate movement of the piston, preferably mechanical displacement of the piston.

[0046] Furthermore, the gear may be driven by the motor by means of a drive. The term “drive” as used herein is a broad term and should be given its common and customary meaning for those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary device for transmitting and/or converting motions. In particular, the drive may be a gear transmission or mechanism. The drive may, for example, be specifically configured to transmit and/or convert motion, such as motor rotation, to the gear. Preferably, the drive may have a gear or transmission ratio other than 1. In particular, the drive may convert or transform motor rotation to the gear, so that the speed of rotation of the gear may be different from the speed of rotation of the motor. Preferably, the drive may transmit motor rotation to the gear, so that the rotation of the gear may be slower than the rotation of the motor. In particular, the motor may be, for example, a motor, specifically a type of motor, with permanent magnets for an excitation field. This type of motor may, for example, provide speed, specifically speed of rotary motion of a drive shaft, where the speed may depend on the applied voltage and the speed may further depend on the load, specifically the load of the drive shaft of the motor. As an example, an increase in load may result in a decrease in speed, so that an increase in load may result, for example, in a decrease in speed. In particular, a change in speed, preferably a change in rotational speed, may result from a change in load. Depending on the design of the motor, for example, the change in speed in response to a defined change in load may be large or small. Preferably, for example, the change in speed in response to a change in load may be small. As an example, there may be a motor that can inherently provide this characteristic, for example, by or as a result of its internal dimensions. The internal dimensions of the motor may be or comprise, for example, strength of the magnets, cross-section of the working air space, number of windings of one or more coils or the like.

[0047] As an example, the ratio of the gearbox, specifically the drive and gear ratio, may be specifically selected to achieve, for example, two effects. In particular, as a first effect, the motor speed may be adapted so that the piston speed, specifically the piston speed driven by the threaded rod, may generate extrusion of the basic insulin rate. Firstly, therefore, the motor speed may be reduced, for example, to an appropriate screw speed, in order to provide, for example, the desired insulin displacement over time. Furthermore, particularly as a second effect, the gearbox, specifically the drive and gear, may, for example, have a ratio, such as a gear ratio, which may provide increased torque from the motor to the screw so that, for example, the motor may run more or less at rest. This may provide, for example, inherent speed regulation, and in particular, the piston speed may be inherently regulated. In particular, inherent speed regulation can be provided, for example, provided that the motor drive voltage can remain substantially constant. The ratio of the rotational speed of the gear to the motor speed can be, for example, in the range of 1 • 10-4 to 1 • 10-8, preferably in the range of 1 • 10-5 to 1 • 10-7, most preferably in the range of 5 • 10-5 to 5 • 10-6. Furthermore, the gear, via the coupling, can drive the threaded rod. Specifically, the gear can drive the threaded rod via the coupling having at least two engagement elements preferably capable of engaging with the threaded rod in at least two axially displaced engagement positions.

[0048] Furthermore, the gear and at least one of the mating elements may be assembled together. In particular, the gear may be assembled together with a bearing and at least one of the mating elements to form a unit. The gear may, for example, be fixed between at least one of the mating elements and the bearing. The term “bearing” as used herein is a broad term and should be given its ordinary and customary meaning for those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary cylindrical object adapted to a side surface of the gear. The bearing may be, for example, a cylindrical lining adapted to the side surface of the gear. In particular, the bearing may be configured, for example, for mechanical stabilization or protection of the gear. The bearing may be configured, for example, for abrasion resistance, force absorption or the like. In particular, the bearing may be part of the unit, whereby the unit may be specifically fixed axially, so that the unit may, for example, be captured in an axial position. Furthermore, for example, the unit may be configured to perform rotary movement. In particular, for example, the unit may still rotate freely. In particular, the unit, in particular the gear mounted together with the mating element, may move, for example, in a combination of radial and axial bearings, specifically to exert axial force on the threaded rod.

[0049] The drive system may further comprise at least one spring pillar mounted concentrically around the threaded rod. Preferably, the at least one spring pillar may be configured to limit movement of the coupling away from the piston. The term “spring pillar” as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, a mechanical catch or stop. Specifically, the spring pillar may be configured to limit movement of the coupling, preferably by limiting movement of the axially acting spring element.

[0050] Furthermore, the mechanical displacement unit may comprise at least one displacement lever configured to exert axial pressure on the piston and/or to axially displace the piston. The term “displacement lever” as used herein is a broad term and should be given its ordinary and customary meaning for those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary device formed to exert mechanical displacement when activated. In particular, the displacement lever may have, for example, a handle shape. In particular, the displacement lever may be configured to exert axial pressure on the piston by means of the threaded rod and/or to axially displace the piston by means of the threaded rod. In particular, the displacement lever may be configured to exert axial pressure on the threaded rod by means of at least one of the engaging elements and by means of the threaded rod on the piston. The travel lever, specifically when activated, can, for example, actuate the coupling to switch from the first coupling state to the second coupling state to the third coupling state and back to the first coupling state by exerting axial pressure on the first coupling element.

[0051] In particular, the drive may be or comprise an arbitrary arrangement or combination of any number of gear elements. Specifically, the drive may comprise, for example, one or more of a sprocket, worm gear, friction wheel, conveyor belt, conveyor chain or the like. Other gear elements and/or combinations thereof may be feasible.

[0052] The drive may further comprise, for example, at least one gear wheel for adjusting and/or defining the transmission ratio between the motor and the gear. Preferably, the drive may comprise more than one gear wheel, such as a combination of several gear elements, for defining the transmission ratio between the motor and the gear. The expression “gear wheel”, as used herein, is a broad expression and should be given its common and customary meaning for those skilled in the art, without being limited to special or specific meanings. The expression may specifically indicate, without limitation, an arbitrary wheel-shaped object configured for transmitting motion by means of rotation around an axis. The gear wheel may be, for example, a toothed wheel, worm gear, friction wheel or the like.

[0053] Furthermore, the drive may comprise at least one belt for transmitting rotation from the motor to the gear. In particular, the belt may be, for example, a toothed belt or friction belt configured for transmitting rotation from the motor to the gear by means of positive locking, such as by means of interlocking teeth, traction or the like.

[0054] In particular, the drive may comprise at least one worm screw configured to transmit and/or convert the rotation of the at least one gear wheel onto the gear in an orthogonal manner. Preferably, the worm screw may be, for example, a worm gear, specifically meshed with a gear shaft, wherein the gear shaft may also be comprised of the drive.

[0055] Specifically, the belt may interact with the first sprocket so as to transmit the rotation of the motor to the first sprocket. Furthermore, the first sprocket may interact with the second sprocket. In this way, the rotation of the first sprocket may be preferentially transmitted to the second sprocket. The second sprocket may additionally interact with a third sprocket. Preferably, the interaction between the second sprocket and the third sprocket may generate transmission of the rotation of the second sprocket to the third sprocket. Furthermore, the third sprocket may interact with a fourth sprocket. Preferably, the interaction between the third sprocket and the fourth sprocket may generate transmission of the rotation of the third sprocket to the fourth sprocket. Furthermore, the fourth sprocket may interact with a fifth sprocket. Preferably, the interaction between the fourth gear wheel and the fifth gear wheel can generate transmission of rotation from the fourth gear wheel to the fifth gear wheel. The fifth gear wheel can preferably be connected to the worm, wherein the worm can interact with the gear. Preferably, a rotation axis of the worm can be arranged in an orthogonal position to a rotation axis of the gear.

[0056] The drive system may further comprise a mechanical occlusion detection system. The term “mechanical occlusion detection system” as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, an arbitrary mechanical system configured to provide information about an insulin flow state or condition. In particular, the mechanical occlusion detection system may be configured to detect blockage or occlusion of the insulin supply. Preferably, the mechanical occlusion detection system may be configured to provide information, such as visual information, about the blockage or occlusion to the user, for example by means of a viewing window. The mechanical occlusion detection system may be, for example, part of the gearbox, such as a gear wheel that is visually detectable and has, for example, a contrasting color or at least one marking. Preferably, therefore, the visually detectable gear wheel may be part of the marking housing or the actuator and may be visible to the user. In particular, a stationary gear wheel may indicate the occurrence or existence of the blockage or occlusion. Alternatively or additionally, the mechanical occlusion detection system may be wholly or partially disposed in a flow path, in particular in an insulin flow path, such as inside a tube.

[0057] The mechanical occlusion detection system may comprise, for example, at least one of an impeller or an Archimedes screw. Specifically, the impeller or the Archimedes screw may be disposed within the insulin flow path. By means of a rod, the impeller or the Archimedes screw may drive an axle. The axle may further be connected to a wheel, wherein the rotation of the wheel may be visually detectable by the user, for example, by means of marking or coloring of the wheel. In particular, the surface wetted by the insulin may be larger, for example, when using the Archimedes screw than when using the impeller, so that, for example, the Archimedes screw may allow visual detection of lower insulin flow rates than the impeller.

[0058] Alternatively or additionally, the mechanical occlusion detection system may comprise, for example, an elastic element, preferably an elastically deformable element, such as an elastic membrane. Specifically, the elastic element may bulge when applied with pressure or force or may be arranged to be visually detectable by the user. Preferably, the static element may additionally be arranged to be in contact with insulin, such as insulin within the flow path. In the event of an occlusion or blockage occurring, the pressure, particularly the fluid pressure of insulin, within the flow path may increase. The elastic membrane that is in contact with the insulin may therefore bulge in the event of an occlusion occurring. In order to increase the visibility of the membrane by the user, the membrane may be configured, for example, to change its coloration upon bulging and/or a magnifying lens may be arranged to enlarge the size of the membrane in order to increase the visibility of the membrane.

[0059] Alternatively or additionally, a float or a suspended body may be arranged in a pressure tube of the flow path. The pressure tube may, for example, be arranged orthogonally or parallel to the flow path of the insulin. In the event of an occlusion or blockage, the pressure, in particular the fluid pressure of the insulin, within the flow path may increase. The float or suspended body may therefore be lifted or elevated by the fluid pressure of the insulin. Preferably, the lifted or elevated position of the float or suspended body may be visible to the user. The occurrence of an occlusion may therefore be visible to the user by checking the position of the float. Preferably, the float or suspended body may be connected to the pressure tube by a spring configured to restore the position of the float during the flow of the insulin; there is, for example, no blockage of the insulin.

[0060] Alternatively or additionally, an object may be disposed in the flow path, preferably on an inclined plane in the flow path. The speed of the insulin flow may maintain the object in a suspended position over the inclined plane. In the event of occlusion or blockage of the insulin flow, the object may sink down the inclined plane. Preferably, the position of the object on the inclined plane may be visible to the user, providing information about the state of insulin flow. Preferably, the object may be connected to a lower end of the inclined plane by a spring configured to ensure that the body sinks down when blockage exists, such as when insulin is not flowing.

[0061] In a further embodiment, an insulin pump is described for delivering insulin to a user. The insulin pump comprises at least one insulin reservoir. Furthermore, the insulin pump comprises at least one drive system; specifically, the drive system set forth above or as further set forth below. The term “insulin reservoir” as used herein is a broad term and should be given its ordinary and customary meaning to those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, a hollow element or container that may be wholly or partially filled with insulin. Specifically, the insulin reservoir may comprise at least one cartridge or vial that may be specifically removable within the insulin pump.

[0062] Furthermore, the insulin pump may comprise a housing. The term “housing” as used herein is a broad term and should be given its common and customary meaning for those skilled in the art, without being limited to special or specific meanings. The term may specifically indicate, without limitation, a basically arbitrary element configured to enclose, in whole or in part, one or more components and provide protection for these one or more components, for example, against mechanical influence and/or moisture. The housing may specifically be or comprise a rigid housing, such as a rigid housing made of one or more plastic materials, metallic materials or combinations thereof. Specifically, the drive system may be in whole or in part disposed in the housing. Additionally, the insulin reservoir may be in whole or in part disposed in the housing. In particular, the housing may have, for example, at least one observation window configured to allow the user to visually check the information on the state or condition of the insulin flow provided by the mechanical occlusion detection system.

[0063] The insulin pump may further comprise a starting element. The starting element may be specifically configured to initiate insulin delivery using the insulin pump.

[0064] In a further embodiment, a method of actuating insulin pumps is described. The method comprises the steps described below. The steps may specifically be performed in the order provided. Furthermore, a different order is possible. The method may comprise additional steps that are not mentioned. It is further possible to perform one or more, or all, of the method steps repeatedly. Furthermore, two or more of the method steps may be performed simultaneously or in a temporally overlapping manner.

[0065] The method comprises the following steps: a. rotating the engine at a previously determined revolution speed; b. converting the engine rotation into continuous linear movement of the piston, using a gearbox, wherein the continuous linear movement of the piston determines the basic rate of insulin delivery; and c. superimposing the continuous linear movement of the piston by means of mechanical displacement of the piston independent of the basic rate, using a mechanical displacement unit.

[0066] For possible options and definitions, reference may be made to the description of the drive system or insulin pump provided above. The method may be specifically configured to drive the insulin pump described above.

[0067] The method may further comprise delivering a metered dose of insulin, wherein the metered dose of insulin is defined by the mechanical displacement of the piston independent of the base rate.

[0068] In particular, the method may further comprise supplying power, specifically electrical power, to the motor using at least one power source. In particular, the method may comprise supplying electrical power to the motor using at least one of a battery or an accumulator. The motor may specifically comprise at least one motor selected from the group consisting of an electric motor, a timing motor or the like. In particular, the timing motor may preferably be a spring-driven timing motor.

[0069] Step (b) of the method may specifically comprise mechanically coupling the piston to a threaded rod. Furthermore, step (b) of the method may comprise coupling the motor to the threaded rod; specifically, coupling the motor to the threaded rod by means of at least one gear. Additionally, step (b) of the method may further comprise mounting the gear concentrically around the threaded rod. Furthermore, step (b) of the method may comprise securing the threaded rod against rotation around its axis, preferably using at least one of a screw or a switch.

[0070] In particular, step (b) of the method may further comprise assembling the gear to the threaded rod by means of a coupling, wherein the coupling has at least two engagement elements capable of engaging with the threaded rod in at least two axially displaced engagement positions. In particular, each of the engagement elements may comprise at least one ratchet. In particular, each of the engagement elements may comprise a rigid base surrounding the threaded rod and ratchet arms extending in an axial direction from the rigid base. Preferably, step (b) of the method may further comprise engaging the ratchet arms with at least one thread of the threaded rod. In this case, in particular, the ratchet arms may extend from the rigid base towards the piston.

[0071] The plug-in elements can preferably be mounted on the threaded rod in such a way that the plug-in elements are interchangeable with each other. In particular, the plug-in elements can be connected by means of at least two support rods, whereby preferably at least one of the plug-in elements can be mounted on the support rods in an axially interchangeable manner.

[0072] In particular, the plug-in elements can be connected by means of at least one axially driven spring element. Furthermore, the plug-in elements can be connected in a rotationally fixed manner.

[0073] The coupling may specifically comprise at least three coupling states. Preferably, three coupling states may be adoptable by the coupling. The three coupling states may specifically be:- first state, wherein, in the first state, the two engagement elements may engage with the threaded rod, the threaded rod may be driven in axial direction by means of rotation of the gear around an axis of the threaded rod and, in the first state, the engagement elements may be located at fixed spatial separation from each other;- second state, wherein, in the second state, the first engagement of the engagement elements may engage with the threaded rod and the second engagement of the engagement elements may disengage from the threaded rod; and the first engagement element may push the threaded rod in axial direction by means of the second engagement element in first axial direction towards the piston; and - third state, in which the first engagement element can disengage from the threaded rod and the second engagement element can engage with the threaded rod and, in the third state, the first engagement element can be pushed back in a second axial direction opposite to the first axial direction.

[0074] Particularly, in the first state, the coupling elements may preferably have a fixed axial separation. Specifically, there may be a fixed axial separation, such as a previously defined distance, between the coupling elements in the first state, particularly in the first state adoptable by the coupling.

[0075] Method step (c) may particularly comprise the second state. In particular, the first engagement of the engagement elements which engage with the threaded rod and the second engagement of the engagement elements which disengage with the threaded rod may be performed in method step (c). Furthermore, method step (c) may comprise pushing the threaded rod in the axial direction via the second engagement element in the first axial direction towards the piston using the first engagement element.

[0076] Step (b) of the method may specifically comprise driving the gear by the motor via a driver. In particular, step (b) of the method may additionally comprise driving the threaded rod by the gear via a coupling. Step (b) of the method may particularly comprise securing the gear between at least one of the mating elements and a bearing. Alternatively or additionally, step (b) of the method may specifically comprise mounting at least one spring pillar concentrically around the threaded rod and, via the spring pillar, limiting movement of the coupling away from the piston.

[0077] In particular, step (c) of the method may comprise exerting axial pressure on the piston and/or axial displacement of the piston, specifically by means of the threaded rod, by a displacement lever, wherein the displacement lever is comprised of the mechanical displacement unit.

[0078] Specifically, step (b) of the method may comprise adjusting the transmission ratio between the motor and the gear using at least one gear wheel, preferably more than one gear wheel, comprised by the driver. Particularly, step (b) of the method may further comprise transmitting the rotation of the motor to the gear using at least one belt, such as a toothed belt, comprised by the driver. Step (b) of the method may further comprise converting the rotation of the at least one gear wheel to the gear in an orthogonal manner using at least one worm screw, such as a helical screw.

[0079] Specifically, step (b) of the method may further comprise a plurality of substeps. In particular, step (b) of the method may comprise the following substeps: b1. transmitting rotation from the motor to the at least one gear wheel; b2. transmitting rotation from the gear wheel to the worm; and b3. transmitting rotation from the worm to the gear such that a rotation axis of the worm is arranged orthogonally to a rotation axis of the gear.

[0080] In particular, substep b1 may comprise transmitting the rotation of the engine to the first sprocket of a chain of sprockets comprising at least two sprockets, preferably three sprockets and, more preferably, four sprockets.

[0081] Furthermore, step (b2) of the method may preferably comprise transmitting the rotation of the last gear wheel of the chain of gear wheels to the worm screw, such as the helical screw.

[0082] Preferably, the method may further comprise detecting occlusions using a mechanical occlusion detection system. For example, undesired occlusion or blockage within the fluid path of the insulin pump may be detected.

[0083] The base rate provided by use of the insulin pump may, for example, preferably be pre-set. Alternatively, the base rate may, for example, be set at a rate desired by the user. In particular, the user may, for example, set the base rate by operating a dial, switch, button or slider. The base rate may also be set or adjustable using at least one electronic interface or user-operated interface.

[0084] The insulin reservoir may preferably be pre-filled. Alternatively, the user may need to fill the insulin reservoir. Specifically, if the insulin reservoir is not pre-filled, the user may fill the insulin reservoir via a syringe, preferably by injecting the insulin into the insulin reservoir, e.g., into a cartridge. The insulin may be injected into the cartridge, e.g., through a membrane, specifically a membrane configured to seal the interior of the cartridge from the outside of the cartridge. Excess air within the insulin reservoir may exit the insulin reservoir through a liquid-sealed opening.

[0085] Priming the insulin pump specifically displaces any air present in the flow path by the insulin and may preferably be accomplished, for example, by activating the mechanical shift lever a number of times. Specifically, the mechanical shift lever may exert axial pressure on the piston, such that, for example, the piston may extrude insulin from the reservoir into the flow path, for example, to displace any air present. Alternatively, priming the insulin pump may be accomplished by moving the insulin reservoir further towards the piston, so as to displace any air present in the flow path. Furthermore, an existing initial breakaway force, specifically increased friction between the piston and the insulin reservoir, may, for example, be overcome by priming the insulin pump, specifically by activating the mechanical shift lever or moving the insulin reservoir further towards the piston.

[0086] The user may specifically remove an insulation layer, such as an insulating foil or the like, from the power source, such as the battery or accumulator, in order to start the insulin pump, so as to specifically start the delivery of insulin.

[0087] To deliver the metered dose, the user may activate the shift lever. Specifically, activating the shift lever may deliver a pre-set amount of insulin. In particular, the pre-set amount of insulin delivered upon activating the shift lever may, for example, depend on the thread, specifically the thread pitch, of the threaded rod.

[0088] The occlusion detection system may inform the user of the occurrence of a blockage or occlusion. In particular, the user may be able to visually detect the delivery of insulin, for example, by means of the information provided by the occlusion detection system. Furthermore, the insulin fill level of the reservoir may also be visually detectable by the user.

[0089] After use, the insulin pump may preferably be discarded. In particular, the insulin pump may be discarded after all the insulin in the insulin reservoir has been delivered to the user.

[0090] The proposed method and devices provide a large number of advantages over known methods and devices of a similar type.

[0091] In particular, using the devices and methods described herein, a drive system, an insulin pump and a method may be provided for the safe and reliable delivery of insulin. In particular, the method and devices provided may, for example, anticipate the need for electronic control and, for example, no display may be required. In particular, mechanical components may, for example, allow for inherent safety. In particular, the proposed method and devices may be powered, for example, by a battery or accumulator, which specifically provide a specific maximum voltage and, for example, delivery of insulin rate higher than the previously set rate may not be possible. In particular, the base rate may be pre-set. In addition, delivery of additional medication may be possible, for example, by adding the additional medication to the reservoir, specifically the insulin reservoir.

[0092] Additionally, for example, the simple construction and reduced number of parts used in the proposed method and devices may allow for more economical production than prior art methods and devices. In particular, the proposed devices may, for example, be disposable, generating a series of advantages of known reusable products. In particular, for example, the resistance of the material to caustic and abrasive cleaning products may not be a problem.

[0093] Furthermore, various sizes of insulin reservoirs may be useful in the proposed devices, allowing, for example, adjustment to individual user needs. Specifically, the proposed insulin pump and drive system may, for example, be able to assist users in replacing the use of insulin pens with the use of insulin pumps.

[0094] In summary and without excluding possible additional realizations, the following realizations can be conceived.

[0095] Embodiment 1: drive system for insulin pumps, comprising:- a motor configured to rotate at a previously determined revolution speed;- a gearbox for converting the motor rotation into continuous linear movement of the piston, wherein the continuous linear movement of the piston determines the basic rate of insulin delivery; and- a mechanical displacement unit configured to override the continuous linear movement of the piston by means of mechanical displacement of the piston independent of the basic rate.

[0096] Embodiment 2: drive system according to the previous embodiment, wherein mechanical displacement of the piston independent of the base rate defines the delivery of a measured dose of insulin.

[0097] Embodiment 3: A drive system according to any of the preceding embodiments, further comprising at least one power source configured to supply power to the motor.

[0098] Embodiment 4: drive system according to the previous embodiment, wherein the power source comprises at least one electrical power source, more specifically at least one of a battery or accumulator.

[0099] Embodiment 5: A drive system according to any of the previous embodiments, wherein the motor comprises at least one motor selected from the group consisting of an electric motor and a timing motor, preferably a spring-driven timing motor.

[00100] Embodiment 6: A drive system according to any of the previous embodiments, wherein the piston is mechanically coupled to a threaded rod.

[00101] Embodiment 7: drive system according to the previous embodiment, wherein the motor is coupled to the threaded rod by means of at least one gear, in particular by means of at least one gear comprised of the gearbox.

[00102] Embodiment 8: drive system according to the previous embodiment, in which the gear is mounted concentrically around the threaded rod.

[00103] Embodiment 9: A drive system according to any of the three previous embodiments, wherein the threaded rod is fixed against rotation around its axis, preferably by at least one of a screw or switch.

[00104] Embodiment 10: drive system according to any of the three previous embodiments, in which the gear is mounted to the threaded rod by means of a coupling and the coupling has at least two engagement elements capable of engaging with the threaded rod in at least two axially displaced engagement positions.

[00105] Embodiment 11: A drive system according to the previous embodiment, wherein each of the engaging elements comprises at least one ratchet and, specifically, the engaging elements form a double ratchet arrangement.

[00106] Embodiment 12: A drive system according to either of the two preceding embodiments, wherein each of the engagement elements comprises a rigid base around the threaded rod, the ratchet arms extend in an axial direction from the rigid base, and the ratchet arms are configured to engage with at least one thread of the threaded rod.

[00107] Embodiment 13: Drive system according to the previous embodiment, wherein the ratchet arms extend from the rigid base toward the piston.

[00108] Embodiment 14: Drive system according to any of the four previous embodiments, wherein the engaging elements are mounted on the threaded rod in such a way that the engaging elements are interchangeable with each other.

[00109] Embodiment 15: Drive system according to the previous embodiment, wherein the plug-in elements are connected by means of at least two support rods and at least one of the plug-in elements is mounted on the support rods in an axially switchable manner.

[00110] Embodiment 16: Drive system according to any of the six previous embodiments, wherein the engaging elements are connected by means of at least one spring element with axial action.

[00111] Embodiment 17: Drive system according to any of the seven preceding embodiments, wherein the engaging elements are connected in a rotationally fixed manner.

[00112] Embodiment 18: Drive system according to any of the eight preceding embodiments, wherein at least three coupling states can be adopted by the coupling:- first state, wherein in the first state the two engagement elements engage with the threaded rod, the threaded rod is driven in axial direction by means of rotation of the gear around an axis of the threaded rod and in the first state the engagement elements are located in fixed spatial separation from each other;- second state, wherein in the second state the first engagement of the engagement elements engages with the threaded rod and the second engagement of the engagement elements disengages from the threaded rod; and the first engagement element pushes the threaded rod in axial direction by means of the second engagement element in first axial direction towards the piston; and- third state, in which the first engagement element disengages from the threaded rod, the second engagement element engages with the threaded rod and, in the third state, the first engagement element is pushed back in a second axial direction opposite to the first axial direction.

[00113] Embodiment 19: A drive system according to the previous embodiment, wherein the mechanical displacement of the piston independent of the basic rate is carried out in the second state.

[00114] Embodiment 20: A drive system according to any of the nine preceding embodiments, wherein the gear is driven by the motor via a driver and the gear, via the coupling, drives the threaded rod.

[00115] Embodiment 21: A drive system according to any of the ten preceding embodiments, wherein the gear is fixed between at least one of the engagement elements and a bearing.

[00116] Embodiment 22: A drive system according to any of the preceding eleven embodiments, wherein the drive system further comprises at least one spring pillar, mounted concentrically around the threaded rod and configured to limit movement of the coupling away from the piston.

[00117] Embodiment 23: Actuator system according to any of the previous embodiments, wherein the mechanical displacement unit comprises at least one displacement lever configured to exert axial pressure on the piston, specifically by means of the threaded rod, more specifically by means of the threaded rod on the piston, and/or axially displace the piston, specifically by means of the threaded rod.

[00118] Embodiment 24: A drive system according to any of the four preceding embodiments, wherein the drive comprises at least one gear wheel, preferably more than one gear wheel, for adjusting the transmission ratio between the motor and the gear.

[00119] Embodiment 25: drive system according to the previous embodiment, wherein the drive comprises at least one belt for transmitting rotation from the motor to the gear.

[00120] Embodiment 26: A drive system according to either of the two preceding embodiments, wherein the drive comprises at least one worm screw configured to transmit and/or convert rotation of the at least one gear wheel to the gear in an orthogonal manner.

[00121] Embodiment 27: A drive system according to any of the three preceding embodiments, wherein the belt interacts with the first gear wheel so as to transmit the rotation of the motor to the first gear wheel, the first gear wheel interacts with the second gear wheel, the second gear wheel additionally interacts with the third gear wheel, the third gear wheel additionally interacts with the fourth gear wheel, the fourth gear wheel additionally interacts with the fifth gear wheel, the fifth gear wheel is connected to the worm, the worm further interacts with the gear, and a rotation axis of the worm is arranged orthogonally to a rotation axis of the gear.

[00122] Embodiment 28: A drive system according to any of the preceding embodiments, wherein the drive system further comprises a mechanical occlusion detection system.

[00123] Embodiment 29: An insulin pump for delivering insulin to users, comprising:- at least one insulin reservoir; and- at least one drive system as defined in any of the preceding embodiments with reference to a drive system.

[00124] Embodiment 30: An insulin pump according to the previous embodiment, wherein the insulin pump additionally comprises a housing.

[00125] Embodiment 31: An insulin pump according to either of the two preceding embodiments, wherein the insulin pump further comprises a starting element configured to initiate insulin delivery using the insulin pump.

[00126] Embodiment 32: A method of actuating insulin pumps, wherein the method comprises: a. rotating a motor at a previously determined revolution speed; b. converting the motor rotation into continuous linear movement of the piston, using a gearbox, wherein the continuous linear movement of the piston determines the basic rate of insulin delivery; and c. superimposing the continuous linear movement of the piston by means of mechanical displacement of the piston independent of the basic rate, using a mechanical displacement unit.

[00127] Embodiment 33: The method of the previous embodiment, wherein the method further comprises providing a metered dose of insulin, wherein the metered dose of insulin is defined by the mechanical displacement of the piston independent of the base rate.

[00128] Embodiment 34: A method according to any of the preceding method embodiments, wherein the method further comprises supplying power, specifically electrical power, to the motor using at least one power source.

[00129] Embodiment 35: method according to the previous embodiment, wherein the method comprises supplying electrical energy to the motor using at least one of a battery or an accumulator.

[00130] Embodiment 36: A method according to any of the preceding method embodiments, wherein the motor comprises at least one motor selected from the group consisting of an electric motor and a timing motor, preferably a spring-driven timing motor.

[00131] Embodiment 37: A method according to any of the preceding method embodiments, wherein step (b) of the method further comprises mechanically coupling the piston to a threaded rod.

[00132] Embodiment 38: method according to the previous embodiment, wherein step (b) of the method further comprises coupling the motor to the threaded rod by means of at least one gear.

[00133] Embodiment 39: method according to the previous embodiment, wherein step (b) of the method further comprises assembling the gear concentrically around the threaded rod.

[00134] Embodiment 40: The method of any of the three preceding embodiments, wherein step (b) of the method further comprises securing the threaded rod against rotation about its axis, preferably using at least one of a screw or switch.

[00135] Embodiment 41: method according to any of the three previous embodiments, in which step (b) of the method comprises assembling the gear to the threaded rod by means of a coupling and the coupling has at least two engagement elements capable of engaging with the threaded rod in at least two axially displaced engagement positions.

[00136] Embodiment 42: method according to the previous embodiment, wherein each of the engaging elements comprises at least one ratchet.

[00137] Embodiment 43: A method according to any of the two preceding embodiments, wherein each of the engagement elements comprises a rigid base around the threaded rod, the ratchet arms extend in an axial direction from the rigid base, and step (b) of the method further comprises engaging the ratchet arms with at least one thread of the threaded rod.

[00138] Embodiment 44: The method of the previous embodiment, wherein the ratchet arms extend from the rigid base toward the piston.

[00139] Embodiment 45: method according to any of the four preceding embodiments, wherein the engagement element is mounted on the threaded rod in such a way that the engagement elements are interchangeable with each other.

[00140] Embodiment 46: Method according to the previous embodiment, wherein the fitting elements are connected by means of at least two support rods and at least one of the fitting elements is mounted on the support rods in an axially switchable manner.

[00141] Embodiment 47: method according to any of the previous six embodiments, wherein the mating elements are connected by means of at least one spring element with axial action.

[00142] Embodiment 48: A method according to any of the seven preceding embodiments, wherein the mating elements are connected in a rotationally fixed manner.

[00143] Embodiment 49: method according to any of the eight preceding embodiments, wherein at least three coupling states can be adopted by the coupling:- first state, wherein in the first state the two engagement elements engage with the threaded rod, the threaded rod is driven in axial direction by means of rotation of the gear around an axis of the threaded rod and in the first state the engagement elements are located in fixed spatial separation from each other;- second state, wherein in the second state the first engagement of the engagement elements engages with the threaded rod and the second engagement of the engagement elements disengages from the threaded rod; and the first engagement element pushes the threaded rod in axial direction by means of the second engagement element in first axial direction towards the piston; and- third state, in which the first engagement element disengages from the threaded rod, the second engagement element engages with the threaded rod and, in the third state, the first engagement element is pushed back in a second axial direction opposite to the first axial direction.

[00144] Embodiment 50: method according to the previous embodiment, wherein step (c) comprises the second state.

[00145] Embodiment 51: The method of any of the nine preceding embodiments, wherein step (b) further comprises driving the gear by the motor via a driver and step (b) further comprises steering the threaded rod by the gear via the coupling.

[00146] Embodiment 52: The method of any of the ten preceding embodiments, wherein step (b) further comprises securing the gear between at least one of the mating elements and a bearing.

[00147] Embodiment 53: A method according to any of the eleven preceding embodiments, wherein step (b) further comprises mounting at least one spring pillar concentrically around the threaded rod and, by means of the spring pillar, limiting movement of the coupling in a direction away from the piston.

[00148] Embodiment 54: The method of any of the preceding embodiments, wherein step (c) further comprises exerting axial pressure on the piston, specifically by means of the threaded rod, more specifically by means of the threaded rod on the piston, and/or axially displacing the piston, specifically by means of the threaded rod, by a displacement lever, wherein the displacement lever is comprised of the mechanical displacement unit.

[00149] Embodiment 55: method according to any of the four previous embodiments, wherein step (b) comprises adjusting the transmission ratio between the motor and the gear using at least one gear wheel, preferably more than one gear wheel, comprised of the driver.

[00150] Embodiment 56: method according to the previous embodiment, wherein step (b) further comprises transmitting rotation from the motor to the gear using at least one belt comprised of the driver.

[00151] Embodiment 57: The method of any of the two preceding embodiments, wherein step (b) further comprises converting the rotation of the at least one gear wheel about the gear in an orthogonal manner using at least one worm gear.

[00152] Embodiment 58: The method of any of the three preceding embodiments, wherein step (b) comprises: b1. transmitting rotation from the motor to the at least one gear wheel; b2. transmitting rotation from the gear wheel to the worm; and b3. transmitting rotation from the worm to the gear such that an axis of rotation of the worm is arranged orthogonally to an axis of rotation of the gear.

[00153] Embodiment 59: method according to the previous embodiment, wherein step (b1) comprises transmitting the rotation of the motor to the first sprocket of a chain of sprockets comprising at least two sprockets, preferably three sprockets, more preferably four sprockets, and step (b2) comprises transmitting the rotation of the last sprocket of the chain of sprockets to the worm screw.

[00154] Embodiment 60: A method according to any of the preceding method embodiments, wherein the method further comprises detecting occlusions using a mechanical occlusion detection system.

BRIEF DESCRIPTION OF THE DRAWINGS

[00155] Additional optional features and embodiments will be described in more detail in the following description of embodiments, preferably in conjunction with the dependent embodiments. The corresponding optional features may be implemented singly and also in any arbitrary feasible combination, as will be understood by those skilled in the art. The scope of the present invention is not restricted by the preferred embodiments. The embodiments are illustrated schematically in the Figures. Identical reference numerals in these Figures indicate identical or functionally comparable elements.

[00156] In the Figures:- Figures 1A and B illustrate embodiments of an insulin pump in perspective view;- Figure 2 illustrates an embodiment of a drive system in perspective view;- Figure 3 illustrates an embodiment of a drive system in top plan view;- Figure 4 illustrates a sectional view of part of an embodiment of a drive system;- Figure 5 illustrates a sectional view of part of an embodiment of a drive system; and- Figure 6 illustrates a flowchart of an embodiment of an insulin pump drive method.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[00157] Figures 1A and 1B illustrate embodiments of an insulin pump 110 in perspective view. The insulin pump 110 comprises a drive system 112 and an insulin reservoir 114. The insulin pump may further comprise a housing 116, wherein the housing may comprise, for example, two separate housing portions configured to encompass, in whole or in part, the drive system 112 and the insulin reservoir 114. Furthermore, as illustrated in Figures 1A and B, the housing may comprise a starting element 118 configured to initiate insulin delivery using the insulin pump 110.

[00158] Figure 2 illustrates an embodiment of drive system 112 in perspective view. The drive system comprises a motor 120 configured to rotate at a predetermined revolution speed. Further, the motor comprises a gearbox 112 for converting rotation of the motor 120 into continuous linear movement of the piston 124. The continuous linear movement of the piston 124 determines the base rate of insulin delivery. Further, the drive system comprises a mechanical displacement unit 126 configured to override the continuous linear movement of the piston 124 by mechanical displacement of the piston 124 independent of the base rate. Further, the drive system 112 may comprise a power source 128, such as a battery or accumulator, configured to supply power to the motor 120. The motor 120 may be, for example, an electric motor.

[00159] The piston 124 may be specifically mechanically coupled to a threaded rod 130. Additionally, the motor 120 may be coupled to the threaded rod 130 via a gear 132. As illustrated, the gear 132 may be mounted concentrically around the threaded rod 130. The threaded rod 130 may be secured against rotation about its axis 134, as illustrated in Figure 3. Specifically, the threaded rod 130 may be secured against rotation about its axis 134 by an alternator 136, as illustrated in Figures 2 and 3.

[00160] The gear 132 may be mounted to the threaded rod 130 by a coupling 138, wherein the coupling 138 may have first engagement element 140 and second engagement element 142, wherein the engagement elements 140, 142 may be capable of engaging with the threaded rod 130 in two axially offset engagement positions. Each of the engagement elements 140, 142 of the coupling 138, as illustrated in Figure 5, may comprise at least one ratchet. Specifically, each of the engagement elements 140, 142 may comprise a rigid base 144 surrounding the threaded rod 130. Each of the engagement elements 140, 142 may further comprise ratchet arms 146 extending in an axial direction from the rigid base 144. In particular, the ratchet arms 146 may extend from the rigid base 144 toward the piston 124. The ratchet arms 146 may be specifically configured to engage with at least one thread of the threaded rod 130, as illustrated in Figure 5. The engagement elements 140, 142 may further be mounted on the threaded rod 130 such that the engagement elements 140, 142 are switchable with each other.

[00161] As illustrated in Figure 4, the engagement elements 140, 142 can be connected via two support rods 148. Furthermore, the engagement elements 140, 142 can be mounted on the support rods 148 such that at least one of the engagement elements 140, 142 can be switchable on the support rods 148. In particular, the engagement elements 140, 142 can be connected via the support rods 148 such that the engagement elements 140, 142 can be fixed rotatably relative to each other. The engagement elements 140, 142 may be further connected via two axially acting spring elements 150. Specifically, the drive system may further comprise a spring pillar 152. The spring pillar 152 may limit movement of the spring elements 150. Furthermore, the spring pillar 152 may be configured to limit movement of the coupling 138 away from the piston 124. As further illustrated in Figures 4 and 5, the gear 132 may be secured between the second engagement element 142 and a bearing 154.

[00162] The coupling 138 may comprise three coupling states. Particularly, three coupling states may be adoptable by the coupling 138. Specifically, in the first coupling state, the first engagement element 140 and the second engagement element 142 may engage with the threaded rod 130. Particularly, in the first coupling state, the two engagement elements 140, 142 may be located in fixed spatial separation from each other on the threaded rod 130. In the first state, the threaded rod 130, specifically the piston 124 connected to the threaded rod 130, may be driven in axial direction by rotation of the gear 132 about the axis 134 of the threaded rod 130. Specifically, in the first coupling state, only the base rate may be delivered to the user by the insulin pump 110.

[00163] In the second coupling state, the first engaging element 140 can be further engaged with the threaded rod 130, wherein the second engaging element 142 can disengage from the threaded rod 130. In particular, the first engaging element 140 can push the threaded rod 130 in an axial direction, specifically along the axis 134 of the threaded rod 130, through the second engaging element 142. In particular, in the second coupling state, the first engaging element 140 can push the threaded rod 130 through the second engaging element 142 in a first axial direction towards the piston 124. In this way, in the second coupling state, the base rate and the metered dose can be delivered to the user by the insulin pump 110. In particular, in the second state, the threaded rod 130, specifically the piston 124 connected to the threaded rod 130, can be disengaged from the threaded rod 130 in an axial direction, specifically along the axis 134 of the threaded rod 130, through the second engaging element 142. In particular, in the second coupling state, the first engaging element 140 can push the threaded rod 130 in an axial direction towards the piston 124. In this way, in the second coupling state, the base rate and the metered dose can be delivered to the user by the insulin pump 110. In particular, in the second state, the threaded rod 130, specifically the piston 124 connected to the threaded rod 130, can be disengaged from the threaded rod 130 in an axial direction, specifically along the axis 134 of ... towards the piston 124 in an axial direction towards the piston 124 in an axial direction towards the piston 124 in an axial The threaded rod 130 may be driven in an axial direction by means of reaction of the gear 132 about the shaft 134, wherein rotation of the gear 132 may drive the threaded rod 130 via the second engagement member 142. Specifically, the movement or part of the movement of the piston 124 powered or driven by the rotation of the gear 132 may generate the delivery of basic rate insulin to the user. Furthermore, in the second state, the piston 124 may be moved in an axial direction by the first engagement member 140 pushing the threaded rod 130. Particularly, the additional movement of the piston 124 may generate additional insulin delivery to the user, such as a metered dose of insulin. The delivery of the additional insulin, such as the metered dose, may be added to the delivery of basic rate insulin in the second state. Specifically, the basic rate insulin may be superimposed on the metered dose. In particular, mechanical displacement of the piston 124 independent of the base rate can be realized in the second state.

[00164] In the third engagement state, the second engagement element 142 can engage with the threaded rod 130 and the first engagement element 140 can disengage from the threaded rod 130. Specifically, the first engagement element 140 can be pushed back in a second axial direction opposite to the first axial direction. The first engagement element 140, for example, can be pushed back by the spring element 150. After the third engagement state, therefore, the coupling can be switched to the first engagement state. As an example, the coupling 138 can be configured to switch from the first engagement state to the second engagement state and from the second engagement state to the third engagement state, preferably repeatedly.

[00165] As further illustrated in Figures 2 and 3, the mechanical displacement unit 126 may comprise a displacement lever 156. In particular, the displacement lever 156 may be configured to exert axial pressure on the piston 124 and/or axially displace the piston 124 when activated. Specifically, activation of the displacement lever 156, for example by manually pushing the displacement lever 156, can exert axial pressure on the piston 124 via the threaded rod 130, more specifically via the first engagement element 140 on the threaded rod 130 and via the threaded rod 130 on the piston 124. The displacement lever 156 can be configured, for example, to actuate or push the coupling 138, specifically the first engagement element 140, such that the coupling is switched from the first engagement state to the second engagement state, from the second engagement state to the third engagement state and from the third engagement state back to the first engagement state. The displacement lever 156 can therefore allow the metered dosage to be delivered to the user, preferably by repeatedly activating the displacement lever 156.

[00166] The drive system 112 may further comprise a driver 158. In particular, the gear 132 may be driven by the motor 120 via the driver 158. The driver 158 may, for example, be part of the gearbox 122. In particular, the driver 158 may comprise a series of gear wheels 160 for adjusting the transmission ratio between the motor 120 and the gear 132. Furthermore, the driver 158 may comprise a belt 162 for transmitting the rotation of the motor 120 to the gear 132, specifically via the gear wheels 160, to the gear 132. Additionally, the driver 158 may comprise a worm 164 for converting the rotation of the gear wheels 160 to the gear 132 in an orthogonal manner. As illustrated in Figures 2 and 3 , the drive may comprise five sprockets 160. First sprocket 166 may comprise, for example, a friction wheel 168 interacting with belt 162 and a gear wheel (not shown) interacting with second sprocket 170. Second sprocket 170 may comprise sprocket 172 and a gear wheel (not shown) for interaction with third sprocket 174. Third sprocket 174 may comprise, for example, sprocket 172 and a gear wheel (not shown) for interaction with fourth sprocket 176, wherein fourth sprocket 176 may comprise sprocket 172 and a gear wheel (not shown) for interaction with fifth sprocket 178. Fifth sprocket 178 may, for example, be connected to worm gear 164.

[00167] The drive system may further comprise a mechanical occlusion detection system 180. In particular, the mechanical occlusion detection system 180 may be configured, for example, to provide information about an undesired occlusion or blockage in an insulin flow path. In particular, the mechanical occlusion detection system 180 illustrated in Figure 3 may provide visual information to the user by providing a visually detectable mark 182 on the second gear wheel 170. In particular, the user may be able to identify the occurrence of an occlusion when the second gear wheel 170 does not rotate, for example, by visually inspecting the detectable mark 182 through an observation window in the shelter 116.

[00168] Figure 6 illustrates a flowchart of one embodiment of a method of actuating an insulin pump. The method comprises step (a) (method step 184) of rotating motor 120 at a previously determined revolution speed. Specifically, motor 120 illustrated in Figures 2 and 3 may be rotated in method step 184.

[00169] Furthermore, the method comprises step (b) (method step 186) of converting the rotation of the motor 120 into continuous linear motion of a piston 124 using a gearbox 122, wherein the continuous linear motion of the piston 124 determines the basic insulin delivery rate. Specifically, in method step 186, the rotation of the motor 120 may be converted into continuous linear motion of the piston 124 using the gearbox 122, as illustrated in Figures 2 and 3.

[00170] The method further comprises step (c) (method step 188) of overriding the continuous linear movement of the piston 124 by mechanically displacing the piston 124 independent of the base rate, using a mechanical displacement unit 126. In particular, the continuous linear movement of the piston 124 may be overridden by mechanically displacing the piston 124, for example, by activating the displacement lever 156 as illustrated in Figures 2 and 3.

[00171] List of reference numerals:110 insulin pump112 drive system114 insulin reservoir116 housing118 starting element120 motor122 gearbox124 piston126 mechanical shift unit128 power source130 threaded rod132 gear134 shaft136 commutator138 coupling140 first engaging element142 second engaging element144 rigid base146 ratchet arms148 support rod150 spring element152 spring pillar 154 bearing156 shift lever158 actuator160 gear wheel162 belt164 worm gear166 first gear wheel168 friction wheel170 second gear wheel172 gear wheel174 third gear wheel176 fourth gear wheel178 fifth gear wheel180 detection system mechanical occlusions182 visually detectable mark184 step a: engine rotation at previously determined revolution speed186 step b: conversion of engine rotation into continuous linear piston motion188 step c: superposition of continuous linear piston motion by mechanical piston displacement independent of the base rate.

Claims (10)

1. DRIVE SYSTEM (112) for insulin pumps (110), the insulin pump (110) being for supplying insulin to a user and comprising at least one insulin reservoir (114), the drive system (112) comprising: - a motor (120) configured to rotate at a previously determined revolution speed; - a gearbox (122) configured to act on a piston (124) of the insulin pump (110), so as to convert rotation of the motor (120) into continuous linear movement of the piston (124) by means of a threaded rod (130) mechanically coupled to the piston (124), wherein the continuous linear movement of the piston (124) determines a basic rate of insulin delivery; and- a mechanical displacement unit (126) configured to act on the piston (124) by superimposing the continuous linear movement of the piston (124) by mechanical displacement of the threaded rod (130), wherein the threaded rod (130) is mechanically coupled to the piston (124) regardless of the basic rate, the threaded rod (130) being fixed against rotation about its axis, wherein the motor (120) is coupled to the threaded rod (130) by means of at least one gear (132), wherein the gear (132) is mounted concentrically around the threaded rod (130), the drive system (112) characterized in that the gear (132) is mounted to the threaded rod (130) by means of a coupling (138) and the coupling (138) has at least two engaging elements (140, 142) capable of engage with the threaded rod (130) in at least two axially displaced engaging positions, in which at least three coupling states can be adopted by the coupling (138):- first state, in which, in the first state, the two engaging elements (140, 142) engage with the threaded rod (130), the threaded rod (130) is driven in the axial direction by means of rotation of the gear (132) around an axis of the threaded rod (130) and, in the first state, the engaging elements (140, 142) are located at a fixed spatial separation from each other;- second state, in which, in the second state, the first engaging element (140) of the engaging elements (140, 142) engages with the threaded rod (130) and the second engaging element (142) of the engaging elements (140, 142) disengages from the threaded rod (130) and the first engagement element (140) pushes the threaded rod (130) in axial direction by means of the second engagement element (142) in first axial direction towards the piston (124); and- third state, in which the first engagement element (140) disengages from the threaded rod (130), the second engagement element (142) engages with the threaded rod (130) and, in the third state, the first engagement element (140) is pushed back in second axial direction opposite to the first axial direction. 2. DRIVE SYSTEM (112) according to claim 1, characterized in that each of the engagement elements (140, 142) comprises at least one ratchet. 3. DRIVE SYSTEM (112) according to any one of claims 1 to 2, characterized in that each of the engagement elements (140, 142) comprises a rigid base (144) around the threaded rod (130), the ratchet arms (146) extend in an axial direction from the rigid base (144) and the ratchet arms (146) are configured to engage with at least one thread of the threaded rod (130). 4. DRIVE SYSTEM (112) according to any one of claims 1 to 3, characterized in that the engaging elements (140, 142) are mounted on the threaded rod (130) in such a way that the engaging elements (140, 142) are interchangeable with each other. 5. DRIVE SYSTEM (112) according to claim 4, characterized in that the plug-in elements (140, 142) are connected by means of at least two support rods (148) and at least one of the plug-in elements (140, 142) is mounted on the support rods (148) in an axially switchable manner. 6. DRIVE SYSTEM (112) according to any one of claims 1 to 5, characterized in that the snap-in elements (140, 142) are connected by means of at least one spring element with axial action (150). 7. DRIVE SYSTEM (112) according to any one of claims 1 to 6, characterized in that the engagement elements (140, 142) are connected in a rotationally fixed manner. 8. DRIVE SYSTEM (112) according to any one of claims 1 to 7, characterized in that the mechanical displacement unit (126) comprises at least one displacement lever (156) configured to exert axial pressure on the piston (124) and/or axially displace the piston (124). 9. METHOD OF DRIVING INSULIN PUMPS (110), the method comprising: a) rotation (184) of a motor (120) at a previously determined revolution speed; b) conversion (186) of rotation of the motor (120) into continuous linear movement of a piston (124) by means of a threaded rod (130) mechanically coupled to the piston (124) using a gearbox (122), in which the continuous linear movement of the piston (124) determines the basic rate of insulin delivery; and c) superposition (188) of the continuous linear movement of the piston (124) by means of a mechanical displacement of the threaded rod (130), in which the threaded rod (130) is mechanically coupled to the piston (124), independently of the basic rate, using a mechanical displacement unit, and the threaded rod (130) being fixed against rotation around its axis in which the motor (120) is coupled to the threaded rod (130) by means of at least one gear (132), in which the gear (132) is mounted concentrically around the threaded rod (130), the method characterized in that the gear (132) is mounted next to the threaded rod (130) by means of a coupling (138) and the coupling (138) has at least two engagement elements (140, 142) capable of engaging with the threaded rod (130) in at least two axially displaced engagement positions, in which at least three engagement states can be adopted by the coupling (138):- first state, in which, in the first state, the two engagement elements (140, 142) engage with the threaded rod (130), the threaded rod (130) is driven in the axial direction by means of rotation of the gear (132) around an axis of the threaded rod (130) and, in the first state, the engagement elements (140, 142) are located at a fixed spatial separation from each other;- second state, in which, in the second state, the first engagement element (140) of the engagement elements (140, 142) engages with the threaded rod (130) and the second engagement element (142) of the engagement elements (140, 142) disengages from the threaded rod (130) and the first engagement element (140) pushes the threaded rod (130) in axial direction by means of the second engagement element (142) in first axial direction towards the piston (124); and- third state, in which the first engagement element (140) disengages from the threaded rod (130), the second engagement element (142) engages with the threaded rod (130) and, in the third state, the first engagement element (140) is pushed back in second axial direction opposite to the first axial direction. 10. METHOD, according to claim 9, characterized in that step (b) comprises: b4) transmitting the rotation of the motor (120) to at least one gear wheel (160); b5) transmitting the rotation of the gear wheel (160) to a worm screw (164); and b6) transmitting the rotation of the worm screw (164) to a gear (132), so that an axis of rotation of the worm screw (164) is arranged orthogonally to an axis of rotation of the gear (132).