Automatic injection device

Abstract

An automatic injection device for injecting fluid in a syringe to an injection site is disclosed. The syringe includes a cartridge, a needle at a first end of the cartridge, and a element movable within the cartridge capable to inject fluid within the cartridge into the injection site. The automatic injection device includes a syringe loading mechanism for loading and fixing the syringe, a syringe driving mechanism having a first motor and a first actuation assembly capable of moving the syringe loading mechanism in a first direction towards the injection site of the target to insert the needle of the syringe into the injection site of the target. A dose control mechanism includes a second motor and a second actuation assembly for moving the movable element of the syringe towards the first end of the cartridge to expel a predetermined dose of fluid from the cartridge into the injection site.

Description

AUTOMATIC INJECTION DEVICECROSS-REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to Chinese Patent Application No. 202311713339.1, Serial No. 2023121400628340, entitled “Automatic Injection Device” filed December 13, 2023, the disclosure of which is hereby incorporated by reference in its entirety.TECHNICAL FIELD

[0002] The present disclosure relates generally to the technical field of medical instruments. In particular, the present disclosure relates to a reusable electromechanical automatic injection device.BACKGROUND OF THE INVENTION

[0003] Some illnesses necessitate regular injections of drugs or products, for instance on a daily basis. In order to simplify the treatment, there are already some automatic injection devices (also called “self-injectors”) that can load and drive a syringe, such as a prefilled syringe, to allow a patient to perform the injection on his / her own.

[0004] In addition, in order to best follow the medication protocol and optimize medical adherence, many injectable drugs require stringent control of injection parameters, including dose volume, injection duration and speed, injection frequency, etc. Automatic injection devices also have advantages in standardization of the injection procedure.

[0005] It is well known that there are three key steps for a self-injection administration procedure: 1) needle insertion; 2) drug dispensing; 3) needle retraction or withdrawal. Currently, most of the automatic injection devices available on the market are either mechanically or electrically powered. Their automatic injection functions mainly focus on the drug dispensing procedure. There are few solutions concerning automatic needle insertion and / or automatic needle retraction.

[0006] In some prior arts, a tension spring is used for needle insertion and / or retraction. This requires reloading of the tension spring by a user after each triggering, thus increasing the complexity of the procedure and misfire risk.

[0007] In some other prior arts, each syringe requires the aid of a disposable cassette with a preloaded spring to achieve insertion of the needle of the syringe, which is costly for both manufacturers and users and less environment-friendly.

[0008] In some other prior arts, an individual motor and gear box are used to control the movement of the syringe and its needle. However, the movement is relatively slow as compared to manual insertion and retraction of a needle because the motor driving mechanism in these prior arts has a complicated or inefficient mechanical structure. Slow insertion and retraction may lead to increased injection pain of the patient, which is undesirable.

[0009] Thus, there is a need to improve existing automatic injection devices.

[0010] It is to be noted that the subject matter claimed herein is not limited to the abovedescribed field, not limited to only addressing any of the disadvantages mentioned above, and not limited to embodiments used or operated only in environments such as those described above. Rather, the background is provided merely to illustrate one exemplary technical field in which some embodiments described herein may be practiced.SUMMARY OF THE INVENTION[Oil] One of the objects of the present disclosure is to overcome one or more of the problems existing in the automatic injection devices in the prior art and achieve other additional advantages.

[0012] The present disclosure provides an automatic injection device for automatically injecting a fluid in a syringe to an injection site of a target. The syringe comprises a cartridge for containing a fluid, a needle provided at a first end of the cartridge, and a movable element movable within the cartridge, the movable element capable of being driven towards the first end of the cartridge to inject the fluid within the cartridge into the injection site of the target via the needle. The automatic injection device comprises: a syringe loading mechanism for loading and fixing the syringe; a syringe driving mechanism comprising a first motor and a first actuation assembly, the first actuation assembly capable of moving the syringe loading mechanism in a first translational direction towards the injection site of the target under a drive of the first motor, to insert the needle of the syringe fixed to the syringe loading mechanism into the injection site of the target; and a dose control mechanism comprising a second motor and a second actuation assembly, the second actuation assembly capable of moving the movable element of the syringe towards the first end of the cartridge under a drive of the second motor so as to expel a predetermined dose of fluid from the cartridge of the syringe and inject it into the injection site of the target.

[0013] According to one embodiment of the present disclosure, the automatic injection device further comprises a housing, the syringe loading mechanism is located within thehousing and comprises: a base having a body extending along a longitudinal direction, wherein the longitudinal direction is parallel to the first translational direction; a syringe holder for loading and fixing the syringe, wherein the syringe holder comprises a recess for accommodating the syringe and a fixing element for fixing the cartridge of the syringe, and wherein the syringe holder is movable along the longitudinal direction relative to the base between a first position in which the syringe holder protrudes from the housing to facilitate loading and fixing the syringe and a second position in which the syringe holder is retracted into the housing; and a coupling mechanism configured to releasably couple the syringe holder to the base when the syringe holder is in the second position.

[0014] According to one embodiment of the present disclosure, a second end of the cartridge of the syringe, opposite to the first end, comprises a radially outwardly extending flange, the fixing element of the syringe holder is configured as a cutout adapted to receive and position the flange to prevent movement of the cartridge of the syringe in the longitudinal direction.

[0015] According to one embodiment of the present disclosure, the coupling mechanism is configured as a push-press type elastic self-locking mechanism comprising at least one first engagement element provided on the syringe holder and at least one second engagement element provided on the body of the base, wherein the first engagement element and the second engagement element are coupled to each other when the push-press type elastic self-locking mechanism is subjected to an urging force for a first time, and the first engagement element and the second engagement element are decoupled when the push-press type elastic selflocking mechanism is subjected to an urging force for a second time.

[0016] According to one embodiment of the present disclosure, the first actuation assembly of the syringe driving mechanism comprises a first actuation element in a cylindrical shape, the first actuation element being rotatable under the drive of the first motor and provided with a first mating structure on an outer peripheral surface thereof, wherein the syringe loading mechanism comprises a mating component for mating with the first actuation element, the mating component comprising a cylindrical inner cavity for receiving the first actuation element and a second mating structure provided on an inner peripheral surface of the cylindrical inner cavity, and wherein when the first actuation element is rotated within the cylindrical inner cavity of the mating component, the first mating structure and the second mating structure cooperate with each other such that the first actuation element is at leastcapable of driving the syringe loading mechanism to move in the first translational direction to insert the needle into the injection site of the target.

[0017] According to an embodiment of the present disclosure, the first actuation element is rotatable in a first rotational direction, and when the first actuation element is rotated in the first rotational direction within the cylindrical inner cavity of the mating component, the first mating structure and the second mating structure cooperate with each other such that the first actuation element drives the syringe loading mechanism to move in the first translational direction to insert the needle into the injection site of the target, and wherein the first actuation element is also rotatable in a second rotational direction opposite to the first rotational direction, and when the first actuation element is rotated in the second rotational direction within the cylindrical inner cavity of the mating component, the first mating structure and the second mating structure cooperate with each other such that the first actuation element drives the syringe loading mechanism to move in a second translational direction opposite to the first translational direction to withdraw the needle from the injection site of the target.

[0018] According to one embodiment of the present disclosure, rotation of the first actuation element in the first rotational direction and rotation of the first actuation element in the second rotational direction are both driven by the first motor.

[0019] According to one embodiment of the present disclosure, the syringe driving mechanism comprises a torsion spring, rotation of the first actuation element in the first rotational direction is driven by the first motor, and rotation of the first actuation element in the second rotational direction is driven by the torsion spring, wherein when the first motor drives the first actuation element to rotate in the first rotational direction, the torsion spring is torsionally loaded to accumulate elastic potential energy.

[0020] According to one embodiment of the present disclosure, the first mating structure is configured as at least one slot extending helically along an outer peripheral surface of the first actuation element from a first end of the first actuation element to a second end of the first actuation element, and wherein the second mating structure is configured as at least one protrusion capable of being received in and reciprocally sliding along the at least one slot to selectively drive the syringe loading mechanism to move in one of the first and second translational directions.

[0021] According to one embodiment of the present disclosure, the first mating structure is configured as four slots provided on an outer peripheral surface of the first actuation element, each slot extending helically from the first end of the first actuation element to the second endof the first actuation element, wherein the four slots are evenly distributed on the outer peripheral surface of the first actuation element such that each slot extends along the outer peripheral surface of the first actuation element by 90°, and the four slots are connected end to end such that adjacent two slots are mirror images of each other, and wherein the second mating structure is configured as at least one protrusion capable of sequentially sliding along two adjacent slots of the four slots, to drive the syringe loading mechanism to move alternately in the first translational direction and the second translational direction opposite to the first translational direction.

[0022] According to one embodiment of the present disclosure, the at least one protrusion is configured as two protrusions spaced apart from each other by 180°, the two protrusions are respectively accommodated in two of the four slots, which are spaced apart from each other by 180°, and each protrusion is capable of sequentially sliding along corresponding two adjacent slots of the four slots to drive the syringe loading mechanism to move alternately in the first and second translational directions.

[0023] According to one embodiment of the present disclosure, when the first actuation element rotates in the first rotational direction from 0° to 90°, the at least one protrusion slides within a first slot of the four slots to drive the syringe loading mechanism to move in the first translational direction, and when the first actuation element continues to rotate in the first rotational direction from 90° to 180°, the at least one protrusion slides within a second slot of the four slots, which is adjacent to the first slot to drive the syringe loading mechanism to move in the second translational direction; and wherein when the first actuation element rotates in the second rotational direction opposite to the first rotational direction from 180° to 90°, the at least one protrusion slides reversely within the second slot of the four slots to drive the syringe loading mechanism to move in the first translational direction, and when the first actuation element continues to rotate in the second rotational direction from 90° to 0°, the at least one protrusion slides reversely within the first slot of the four slots to drive the syringe loading mechanism to move in the second translational direction.

[0024] According to one embodiment of the present disclosure, the syringe driving mechanism comprises a torsion spring, rotation of the first actuation element in the first rotational direction is driven by the first motor, and rotation of the first actuation element in the second rotational direction is driven by the torsion spring, wherein when the first motor drives the first actuation element to rotate in the first rotational direction, the torsion spring is torsionally loaded to accumulate elastic potential energy.

[0025] According to one embodiment of the present disclosure, the syringe driving mechanism further comprises a locking mechanism, wherein the first actuation element is not rotatable when the locking mechanism is locked, and the first actuation element is rotatable when the locking mechanism is unlocked.

[0026] According to one embodiment of the present disclosure, the locking mechanism comprises: a control element which is fixedly connected, via a shaft element extending in an axial direction, with the first actuation element in a way so that they are spaced apart from each other, wherein the control element comprises at least one through-hole extending in the axial direction and at least one key pin provided in a first portion of the at least one through- hole, the key pin is spring-loaded such that a first end of the key pin protrudes from a corresponding through-hole in a locked state of the locking mechanism; a locking element provided between the first actuation element and the control element and comprising at least one locking bar extending along the axial direction, wherein the locking element is movable along the axial direction such that in the locked state of the locking mechanism, the at least one locking bar is inserted into a second portion of the at least one through-hole of the control element; at least one elastic element that urges the locking element to push the at least one locking bar of the locking element into the second portion of the at least one through-hole of the control element; an unlocking element configured to press the first end of the key pin back into the corresponding through-hole such that a second end of the key pin opposite to its first end can push the at least one locking bar of the locking element out of the corresponding through-hole, thereby achieving unlocking of the locking mechanism.

[0027] According to one embodiment of the present disclosure, the control element comprises two through-holes spaced apart from each other by 180° and two key pins respectively provided in first portions of the two through-holes, and the locking element comprises two locking bars spaced apart from each other by 180°, each locking bar being insertable into a second portion of a corresponding one of the two through-holes.

[0028] According to one embodiment of the present disclosure, the control element comprises four through-holes spaced apart from each other by 90° and two key pins respectively provided in first portions of two of the four through-holes, which are spaced apart from each other by 180°, and the locking element comprises four locking bars spaced apart from each other by 90°, each locking lever being insertable into a second portion of a corresponding one of the four through-holes.

[0029] According to one embodiment of the present disclosure, the unlocking element is connected to the first motor and can be rotated under the drive of the first motor, and the control element further comprises at least one push portion adapted to mate with the unlocking element, and after the unlocking element unlocks the locking mechanism, the unlocking element can also rotate the control element via the at least one push portion and thus rotate the first actuation element.

[0030] According to one embodiment of the present disclosure, the control element comprises two push portions adapted to mate with the unlocking element, the two push portions are configured in the form of bosses and spaced apart from each other by 180°, and the unlocking element comprises two portions adapted to abut and push the two push portions simultaneously.

[0031] According to one embodiment of the present disclosure, the second actuation assembly of the dose control mechanism comprises a screw and a second actuation element sleeved on the screw, the second actuation element comprising an urging portion adapted to urge the movable element of the syringe, wherein the screw can be rotated in either of a first rotational direction and a second rotational direction opposite to the first rotational direction under the drive of the second motor, and when the screw is rotated in the first rotational direction, the second actuation element is translated on the screw towards the first end of the cartridge to translate the movable element of the syringe towards the first end of the cartridge via the urging portion.

[0032] According to one embodiment of the present disclosure, the movable element of the syringe comprises a plunger rod, the urging portion of the second actuation element being adapted to urge an end of the plunger rod.

[0033] According to one embodiment of the present disclosure, the syringe comprises a shield cap for shielding the needle, and the automatic injection device comprises a catch element for the shield cap, which can be sleeved on an outer periphery of the shield cap and can remove the shield cap from the syringe to expose the needle.

[0034] According to one embodiment of the present disclosure, the catch element comprises two or more circumferentially distributed elastic fingers, a free end of each elastic finger comprising a hook portion extending radially inward, and when the catch element is sleeved on an outer periphery of the shield cap, the hook portion hooks an outer end face of the shield cap to enable removal of the shield cap from the syringe.

[0035] According to one embodiment of the present disclosure, the housing comprises an opening for the syringe holder to protrude, at least a portion of the catch element can be inserted into the opening, and wherein the coupling mechanism is configured as a push-press type elastic self-locking mechanism which can be coupled and decoupled by pressing the catch element.

[0036] According to one embodiment of the present disclosure, the automatic injection device comprises a control unit for controlling at least one of start, stop, operation duration, rotation direction, rotation speed, rotation angle and rotation frequency of the first motor and the second motor.

[0037] According to one embodiment of the present disclosure, the automatic injection device further comprises a power supply element for providing power to the first motor and the second motor.

[0038] According to one embodiment of the present disclosure, the housing of the automatic injection device comprises at least one of: a contact sensor for detecting whether the automatic injection device is in contact with the injection site of the target; an indicating light for indicating an operating status of the automatic injection device; a power port for supplying external power to the first motor, the second motor and the control unit, or charging the power supply element when the power supply element is a rechargeable battery; a user interface comprising at least one of a display screen and a button such that a user can set operating parameters of the automatic injection device or input user instructions.

[0039] According to one embodiment of the present disclosure, the first motor is a servo motor or a stepper motor, and wherein the second motor is a servo motor or a stepper motor.

[0040] It is to be noted that aspects of the present disclosure that are described with respect to one embodiment may be incorporated into other different embodiments, although not specifically described with respect to said other different embodiments. In other words, all embodiments and / or features of any embodiment may be combined in any manner and / or combination as long as they do not contradict each other.BRIEF DESCRIPTION OF THE DRAWINGS

[0041] For easy understanding of the above-mentioned and other features and advantages of the present disclosure, the present disclosure will be described in more details with reference to specific embodiments of the present disclosure which are shown in the accompanying drawings. The accompanying drawings depict only typical embodiments of the presentdisclosure, and are therefore not to be considered as limitation of the scope of the present disclosure, wherein:

[0042] Fig. 1 is a schematic principle diagram of an automatic injection device according to the present disclosure;

[0043] Fig. 2 is a schematic principle diagram of a catch element for a needle shield cap and a syringe loading mechanism of an automatic injection device according to the present disclosure;

[0044] Fig. 3 is a schematic structural diagram of a syringe loading mechanism of an automatic injection device according to the present disclosure;

[0045] Fig. 4 is a schematic diagram of the steps of loading a syringe onto a syringe loading mechanism;

[0046] Fig. 5 is a schematic principle diagram of a syringe driving mechanism of an automatic injection device according to the present disclosure;

[0047] Fig. 6 is a schematic principle diagram of the syringe driving mechanism of Fig. 5 in a locked state;

[0048] Fig. 7 is a schematic principle diagram of the syringe driving mechanism of Fig. 5 in an unlocked state;

[0049] Fig. 8 is a schematic principle diagram of a dose control mechanism of an automatic injection device according to the present disclosure;

[0050] Fig. 9 is a schematic diagram of the steps of injection using the dose control mechanism of the automatic injection device according to the present disclosure;

[0051] Figs. 10a and 10b are respectively schematic structural diagrams of an automatic injection device according to one embodiment of the present disclosure, shown from different angles;

[0052] Fig. Ila is an exploded view of the automatic injection device shown in Figs. 10a and 10b;

[0053] Fig. 1 lb shows an internal structure of the automatic injection device shown in Figs. 10a and 10b;

[0054] Fig. 12 is a schematic structural diagram of a syringe loading mechanism of an automatic injection device according to one embodiment of the present disclosure;

[0055] Figs. 13a to 13c are respectively schematic structural diagrams of a base of the syringe loading mechanism of Fig. 12, shown from different angles;

[0056] Fig. 14 is a schematic structural diagram of a syringe holder of the syringe loading mechanism of Fig. 12;

[0057] Fig. 15 is a schematic structural diagram of a second engagement element of a coupling mechanism of a syringe loading mechanism according to one embodiment of the present disclosure;

[0058] Fig. 16 is a schematic structural diagram of a first engagement element and a second engagement element of a coupling mechanism of a syringe loading mechanism according to one embodiment of the present disclosure when they are coupled to each other;

[0059] Fig. 17 is a schematic structural diagram of a syringe;

[0060] Fig. 18 is a schematic structural diagram of the syringe of Fig. 17 when loaded onto a syringe loading mechanism;

[0061] Fig. 19a shows a schematic structural diagram of a syringe driving mechanism of an automatic injection device according to one embodiment of the present disclosure;

[0062] Fig. 19b is an exploded view of the syringe driving mechanism shown in Fig. 19a;

[0063] Fig. 20 is a schematic structural diagram of the syringe driving mechanism of Fig.19a and the syringe loading mechanism of Fig. 12 when they are assembled together;

[0064] Fig. 21 is a schematic structural diagram of a driving element of the syringe driving mechanism of Fig. 19a;

[0065] Figs. 22a and 22b are schematic structural diagrams of a locking element of the syringe driving mechanism of Fig. 19a, shown from different angles;

[0066] Fig. 22c is a schematic structural diagram of an elastic element for the locking element of Figs. 22a and 22b;

[0067] Figs. 23a and 23b are schematic structural diagrams of a control element of the syringe driving mechanism of Fig. 19a, shown from different angles;

[0068] Fig. 23c is a schematic structural diagram of the control element of Fig. 23a and the driving element of Fig. 21 when they are connected to each other;

[0069] Fig. 24 is a schematic structural diagram of a spring-loaded key pin of the syringe driving mechanism of Fig. 19a;

[0070] Fig. 25 is a schematic structural diagram of the key pin of Fig. 24 placed into a through-hole of the control element of Fig. 23a;

[0071] Fig. 26 is a schematic structural diagram of an unlocking element and a motor of the syringe driving mechanism of Fig. 19a;

[0072] Fig. 27 is a schematic structural diagram of a dose control mechanism of an automatic injection device according to one embodiment of the present disclosure;

[0073] Fig. 28 is a schematic structural diagram of the dose control mechanism of Fig. 27 in cooperation with a syringe;

[0074] Fig. 29 is a schematic position diagram of the dose control mechanism of Fig. 27 and the syringe loading mechanism of Fig. 12;

[0075] Figs. 30a and 30b are respectively schematic structural diagrams of a catch element according to one embodiment of the present disclosure, shown from different angles;

[0076] Fig. 30c is a schematic structural diagram of the catch element of Fig. 30a sleeved on an outer periphery of a shield cap of a syringe;

[0077] Fig. 31 is a schematic time sequence diagram of synergized control of a first motor of a syringe driving mechanism and a second motor of a dose control mechanism by a control unit according to one embodiment of the present disclosure.

[0078] It should be understood that, the same reference numbers indicate the same elements throughout the drawings. In the drawings, for clarity, dimensions of some features may vary and are not drawn to scale.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0079] The present disclosure will be described below with reference to the drawings, in which certain embodiments of the present disclosure are shown. It should be understood, however, that the present disclosure may be presented in many different ways and is not limited to the embodiments described below; in fact, the embodiments described below are intended to make the disclosure of the present disclosure more complete and to fully convey the protection scope of the present disclosure to those skilled in the art. It should also be understood that, the embodiments disclosed herein can be combined in various ways to provide more additional embodiments.

[0080] It should be understood that, the terminology used in the description is for the purpose of describing particular embodiments only and is not intended to limit the present disclosure. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the meaning as commonly understood by those skilled in the art. Well-known functions or constructions may not be described in detail for brevity and / or clarity.

[0081] The singular forms “a”, “an” and “the” used in the description all include the plural forms, unless clearly indicated otherwise. The terms “comprise”, “include” and “contain” usedin the description indicate the presence of stated features, but do not preclude the presence of one or more other features. The term “and / or” used in the description includes any and all combinations of one or more of the listed items.

[0082] In the description, when an element is referred to as being “on”, “attached” to, “connected” to, “coupled” to, “contacting”, etc., another element, it can be directly on, attached to, connected to, coupled to or contacting the other element, or an intervening element may be present. In contrast, when an element is referred to as being “directly on”, “directly attached” to, “directly connected” to, “directly coupled” to or “directly contacting” another element, there would be no intervening element.

[0083] In the description, the term “first”, “second”, or “third” is used merely for ease of illustration and is not intended to be limiting. Any technical features denoted by “first”, “second”, or “third” are interchangeable.

[0084] In the description, spatially relative terms, such as “upper”, “lower”, “front”, “rear”, “top”, “bottom” and the like, may illustrate one feature’s relationship with another feature in the drawings. It should be understood that the spatially relative terms encompass different orientations of the device in use or operation in addition to the orientation depicted in the drawings. For example, when the device in the drawings is inverted, features originally described as being “below” other features would then be described as being “above” the other features. The device may also be otherwise oriented (rotated by 90 degrees or at other orientations), and at this time the relative spatial relationship will be interpreted accordingly.

[0085] In the description, the term “automatic” is used to indicate that at least some operations of the syringe (such as at least some of insertion of a needle of the syringe into an injection site, withdrawal of the needle of the syringe from the injection site, injection of a fluid within the syringe into the injection site, or the like) are performed by an automatic injection device according to the present disclosure without having to be performed manually by a user.

[0086] Referring to Fig. 1 and Figs. 10a to 11b, an automatic injection device 100 according to one embodiment of the present disclosure is shown, which may be used to automatically inject a fluid (e.g., a liquid drug, or other fluids) in a syringe 200 to an injection site of a target (e.g., a living patient such as a human or animal, or other inanimate targets to be injected).

[0087] The automatic injection device 100 according to the present disclosure may be an electromechanical automatic injection device and it is reusable, which will be described indetail below. The syringe 200 may be a syringe that can be prefilled or a syringe that has already been prefilled. As shown more clearly in Figs. 2 and 17, the syringe 200 may comprise a cartridge 210 for containing a fluid, a needle 220 provided at a first end of the cartridge 210, and a movable element 230 movable within the cartridge 210. A second end of the cartridge 210, opposite to the first end, may comprise a radially outwardly extending flange 2101. The movable element 230 can at least be driven towards the first end of the cartridge 210 to expel the fluid within the cartridge 210 and inject it into an injection site of a target via the needle 220. For a syringe that can be prefilled, the movable element 230 may also be pulled towards the second end of the cartridge 210, opposite to the first end, to draw the fluid into the cartridge of the syringe. The movable element 230 may comprise a stopper 2301 and a plunger rod 2302. A first end of the plunger rod 2302 may be fixedly connected with the stopper 2301, and a second end of the plunger rod 2302 may be provided with a flange 2303 extending radially outward from the body of the plunger rod 2302. The plunger rod 2302 can be pushed or pulled by means of the flange 2303 to expel the fluid within the cartridge 210 or draw a fluid into the cartridge 210. In some prefilled syringes 200, the movable element 230 may comprise only the stopper 2301 and may not comprise the plunger rod 2302. The stopper 2301 may be pushed directly by other driving elements to expel the fluid within the cartridge 210. The syringe 200 may also comprise a shield cap 240 for shielding the needle 220 to prevent the needle 220 from causing needle stick injury to the user.

[0088] The automatic injection device 100 may comprise a syringe loading mechanism 110, a syringe driving mechanism 120, and a dose control mechanism 130. The syringe loading mechanism 110 is configured to load and fix the syringe 200. The syringe driving mechanism 120 is configured to at least drive the syringe loading mechanism 110 in a first translational direction towards the injection site of the target to insert the needle 220 of the syringe 200 fixed to the syringe loading mechanism 110 into the injection site of the target. In some cases, the syringe driving mechanism may also be configured to drive the syringe loading mechanism 110 to move in a second translational direction away from the injection site of the target to withdraw the needle 220 of the syringe 200 from the injection site of the target after the injection is completed, wherein the second translational direction is opposite to the first translational direction. The dose control mechanism 130 is configured to move the movable element 230 of the syringe 200 towards the first end of cartridge 220 to expel a predetermined dose of fluid from the cartridge 210 of the syringe 200 and inject it into the injection site of the target.

[0089] In some embodiments, the automatic injection device 100 may also comprise a control unit 140 to at least control operations of the syringe driving mechanism 120 and the dose control mechanism 130. The automatic injection device 100 may also comprise a housing 150. Some or all of the syringe loading mechanism 110, the syringe driving mechanism 120, the dose control mechanism 130 and the control unit 140 may be housed within the housing 150. The syringe loading mechanism 110, the syringe driving mechanism 120, the dose control mechanism 130, the control unit 140 and the housing 150 will be described one by one in detail below.

[0090] Referring first to Fig. 3 and Figs. 12-16, a syringe loading mechanism 110 according to one embodiment of the present disclosure is shown. In this embodiment, the syringe loading mechanism 110 may be housed within the housing 150 and may comprise a base 111, a syringe holder 112 for loading and fixing the syringe 200, and a coupling mechanism 113. The base 111 may have a body 1111 extending along a longitudinal direction L, wherein the longitudinal direction L is parallel to the aforementioned first translational direction. The syringe holder 112 may comprise a recess 1121 for accommodating the syringe 200 and is movable in the longitudinal direction L relative to the base 111 between a first position in which the syringe holder 112 may protrude from the housing 150 to facilitate loading and fixing the syringe 200, and a second position in which the syringe holder 112 may be retracted into the housing 150. In order to facilitate stable movement of the syringe holder 112 in the longitudinal direction L relative to the base 111, the syringe holder 112 may comprise two guide rails 1122 on either side of the recess 1121, and the body 1111 of the base 111 may comprise two guide slots 1112 for receiving the two guide rails 1122. In other embodiments, the body 1111 of the base 111 may comprise two guide rails and the syringe holder 112 may comprise two guide slots located on either side of the recess 1121 and used for receiving the two guide rails of the base 111.

[0091] In some embodiments, the syringe holder 112 may also comprise a fixing element 1123 for fixing the cartridge 210 of the syringe 200. In the embodiment shown in Fig. 14, the fixing element 1123 is configured as a cutout. The cutout may be configured to receive and position the flange 2101 of the cartridge 210 of the syringe 200 (as shown in Fig. 18) to prevent the cartridge 210 of the syringe 200 from moving in the longitudinal direction L. In other embodiments, the fixing element 1123 may have other different configurations. For example, the fixing element 1123 may comprise one or more of a hoop element, a strap element, a snap element, a stop element, or other similar fastening elements.

[0092] The coupling mechanism 113 may be configured to releasably couple the syringe holder 112 to the base 111 when the syringe holder 112 is in the second position relative to the base 111. When the syringe holder 112 is coupled to the base 111, the syringe holder 112, together with the cartridge 201 of the syringe 200 fixed thereto, will not be able to move relative to the base 111 in the longitudinal direction L. For ease of operation, the coupling mechanism 113 may be configured as a push-press type elastic self-locking mechanism. As shown in Fig. 3 and Figs. 14-16, the push-press type elastic self-locking mechanism may comprise at least one first engagement element 1131 provided on the syringe holder 112 and at least one second engagement element 1132 provided on the body 1111 of the base 111, wherein the first engagement element 1131 and the second engagement element 1132 may be coupled to each other when the push-press type elastic self-locking mechanism is subjected to an urging force for the first time, and the first engagement element 1131 and the second engagement element 1132 may be decoupled when the push-press type elastic self-locking mechanism is subjected to an urging force for the second time, and so on. In the embodiment shown in Figs. 14-16, each first engagement element 1131 may comprise a head 1133 in the shape of a mushroom, and each second engagement element 1132 may comprise a pair of gripping jaws 1134 for gripping the head 1133 of the first engagement element 1131. The pair of gripping jaws 1134 may approach each other to grip the head 1133 of the first engagement element 1131, thereby coupling the syringe holder 112 to the base 111; and the pair of gripping jaws 1134 may be away from each other to release the head 1133 of the first engagement element 1131, thereby decoupling the syringe holder 112 from the base 111. The approaching and separating of the pair of gripping jaws 1134 to and from each other may be controlled by a push-press type elastic assembly (not shown in the drawings) provided in each second engagement element 1132. The push-press type elastic assembly may be configured to cause the pair of gripping jaws 1134 to approach each other to grip the head of the first engagement element 1131 when the first engagement element 1131 urges the second engagement element 1132 for the first time, and move the pair of gripping jaws 1134 away from each other to release the head of the first engagement element 1131 when the first engagement element 1131 urges the second engagement element 1132 for the second time. The specific structure of the pushpress type elastic assembly may be commonly known (e.g., it may be similar to a push-press type elastic assembly used for a mechanism for placing a memory card or SIM card in a mobile phone), which will not be described in detail here. By configuring the coupling mechanism 113 as a push-press type elastic self-locking mechanism, coupling and decoupling of thesyringe holder 112 and the base 111 can be easily achieved. In some embodiments, the coupling mechanism 113 may also comprise an elastic element (not shown in the drawings) arranged between the syringe holder 112 and the base 111, and the elastic element may be configured to push the syringe holder 112 out of the housing 150 in the longitudinal direction L when the syringe holder 112 and the base 111 are decoupled.

[0093] In other embodiments according to the present disclosure, when the syringe loading mechanism 110 is configured to be directly exposed from the housing 150 (e.g., the housing 150 comprises an opening for exposing the syringe loading mechanism 110), the syringe 200 may be loaded and fixed directly to the syringe holder 112 without the need to move the syringe holder 112 of the syringe loading mechanism 110. In this case, the syringe loading mechanism 110 may comprise only the syringe holder 112, or the base 111 and the syringe holder 112 of the syringe loading mechanism 110 may be fixedly connected with each other or integrally formed.

[0094] Next, referring to Figs. 5 to 7 and Figs.19a to 26, the syringe driving mechanism 120 of the automatic injection device 100 according to one embodiment of the present disclosure will be described.

[0095] The syringe driving mechanism 120 may comprise a first motor 121 and a first actuation assembly 122. In some embodiments, the first motor 121 may be a servo motor or a stepper motor. The first actuation assembly 122 is capable of moving the syringe loading mechanism 110 in a first translational direction towards the injection site of the target under the drive of the first motor 121 to insert the needle 220 of the syringe 200 fixed to the syringe loading mechanism 110 into the injection site of the target. By means of such a syringe driving mechanism 120, it is possible to at least achieve automatic insertion of the needle 220 of the syringe 200 into the injection site of the target, thereby simplifying the manual operation procedure and reducing the operation difficulties for users. In other embodiments, the first actuation assembly 122 is also capable of moving the syringe loading mechanism 110 in a second translational direction away from the injection site of the target (which may be achieved by means of the drive of the first motor 121, or by means of other components, which will be described in detail below) to withdraw the needle 220 of the syringe 200 from the injection site of the target after the injection is completed. By means of such a syringe driving mechanism 120, it is possible to achieve both automatic insertion and automatic withdrawal of the needle 220 of the syringe 200, thereby further simplifying the manual operation procedure and further reducing the operation difficulties for users.

[0096] In some embodiments, the first actuation assembly 122 of the syringe driving mechanism 120 may be configured to move the syringe loading mechanism 110 through rotation of a rotating element that the first actuation assembly 122 comprises. In these embodiments, the first actuation assembly 122 of the syringe driving mechanism 120 may comprise a generally cylindrical first actuation element 1221 (as shown in Figs. 19a to 21). The first actuation element 1221 may be rotated in a first rotational direction (e.g., one of clockwise and counterclockwise directions) and an opposite second rotational direction (e.g., the other of clockwise and counterclockwise direction) under the drive of the first motor 121. The syringe driving mechanism 120 is configured to drive, by rotation of the first actuation element 1221, the syringe loading mechanism 110 to move in a first translational direction towards the injection site of the target and in a second translational direction away from the injection site of the target. Accordingly, the syringe loading mechanism 110 may comprise a mating component 1113 for mating with the first actuation element 1221. In the case where there is a base 111, the mating component 1113 may be fixedly connected with the body 1111 of the base 111 and suspended below the body 1111 of the base 111. In the case where there is no base 111, the mating component 1113 may be directly fixedly connected with the syringe holder 112 and suspended below the syringe holder 112. The mating component 1113 may comprise a cylindrical inner cavity 1114 (as shown in Figs. 13a tol3c) for receiving the first actuation element 1221.

[0097] A first mating structure 1222 may be provided on an outer peripheral surface of the generally cylindrical first actuation element 1221 of the first actuation assembly 122 of the syringe driving mechanism 120. Correspondingly, a second mating structure 1115 that cooperates with the first mating structure 1222 may be provided on an inner peripheral surface of the cylindrical inner cavity 1114 of the mating component 1113 of the syringe loading mechanism 110. When the first actuation element 1121 rotates within the cylindrical inner cavity 1114 of the mating component 1113, the first mating structure 1222 and the second mating structure 1115 may cooperate with each other such that the first actuation element 1221 can drive the syringe loading mechanism 110 to move in the first translational direction to insert the needle 120 into the injection site of the target. In some cases, when the first actuation element 1221 rotates within the cylindrical inner cavity 1114 of the mating component 1113, the first mating structure 1222 and the second mating structure 1115 may also cooperate with each other such that the first actuation element 1221 can drive the syringe loading mechanism110 to move in the second translational direction to withdraw the needle 120 from the injection site of the target.

[0098] The first mating structure 1222 on the outer peripheral surface of first actuation element 1221 of the syringe driving mechanism 120 may be configured as at least one slot that extends helically along the outer peripheral surface from a first end of the first actuation element 1221 to a second end of the first actuation element 1221. Correspondingly, the second mating structure 1115 on the inner peripheral surface of the cylindrical inner cavity of the mating component 1113 of the syringe loading mechanism 110 may be configured as at least one protrusion which can be accommodated in the at least one slot and can slide along the at least one slot to selectively drive the syringe loading mechanism 120 to move in one of the first and second translational directions.

[0099] In some embodiments, the at least one protrusion can slide reciprocally (i.e., slide in opposite directions) within the at least one slot such that when the at least one protrusion slides in a first direction within the at least one slot, the syringe loading mechanism 120 is driven in the first translational direction, and when the at least one protrusion slides in a second direction, opposite to the first direction, within the at least one slot, the syringe loading mechanism 120 is driven in the second translational direction. This may be achieved by changing the rotation direction of the first actuation element 1221.

[0100] However, in the embodiment shown in Figs. 19a to 21, the case is different. In the embodiment shown in Figs. 19a to 21, the first mating structure 1222 on the outer peripheral surface of the first actuation element 1221 of the syringe driving mechanism 120 is configured as four slots provided on the outer peripheral surface. Each slot extends helically along the outer peripheral surface of the first actuation element 1221 from a first end of the first actuation element 1221 to a second end of the first actuation element 1221. The four slots are evenly distributed on the outer peripheral surface of first actuation element 1221 such that each slot extends along the outer peripheral surface of the first actuation element 1221 by 90°, and the four slots are connected end to end such that two adjacent slots are mirror images of each other. At least one protrusion on the inner peripheral surface of the cylindrical inner cavity of the mating component 1113 of the syringe loading mechanism 110 can slide sequentially along two adjacent slots of the four slots to drive the syringe loading mechanism 110 to move alternately in a first translational direction and a second translational direction opposite to the first translational direction. In this process, the rotational direction of the first actuation element 1221 does not need to be changed every time.

[0101] Specifically, in the embodiment shown in Figs. 19a to 21, when the first actuation element 1221 rotates in a first rotational direction from 0° to 90°, the at least one protrusion can slide within a first slot of the four slots to drive the syringe loading mechanism 110 to move in the first translational direction; then, when the first actuation element 1221 continues to rotate in the first rotational direction from 90° to 180°, the at least one protrusion enters and slides within a second slot of the four slots which is adjacent to the first slot, and since the second slot and the first slot are mirror images of each other, the sliding will drive the syringe loading mechanism 110 to move in the second translational direction. In other words, during the rotation of the first actuation element 1221 in the first rotational direction by 180°, the syringe loading mechanism 110 completes one change of moving direction, so that the needle 220 of the syringe 200 can accomplish one complete cycle of insertion into and withdrawal from the injection site of the target. After that, when the first actuation element 1221 rotates in a second rotational direction opposite to the first rotational direction from 180° to 90°, the at least one protrusion may slide reversely within the second slot of the four slots to drive the syringe loading mechanism 110 to move in the first translational direction, and when the first actuation element 1221 continues to rotate in the second rotational direction from 90° to 0°, the at least one protrusion may return to and slide reversely within the first slot of the four slots to drive the syringe loading mechanism 110 to move in the second translational direction. During the rotation of the first actuation element 1221 in the second rotational direction by 180°, the syringe loading mechanism 110 completes another change of moving direction, so that the needle 220 of the syringe 200 accomplishes another complete cycle of insertion into and withdrawal from the injection site of the target.

[0102] In the embodiment shown in Figs. 13a tol3c, the second mating structure 1115 on the inner peripheral surface of the cylindrical inner cavity of the mating component 1113 of the syringe loading mechanism 110 is configured as two protrusions spaced apart from each other by 180°, and the two protrusions are respectively received in two of the four slots, which are spaced apart from each other by 180° (e.g., respectively received in the first slot and the third slot, or respectively received in the second slot and the fourth slot). Each protrusion can sequentially slide along corresponding two adjacent slots of the four slots (e.g., the first protrusion can sequentially slide along the first slot and the second slot, and the second protrusion can sequentially slide along the third slot and the fourth slot) to drive the syringe loading mechanism 110 to move alternately in the first and second translational directions. Themovement process of the two protrusions is the same as the movement process described previously with respect to at least one protrusion, which is not repeated here.

[0103] In some embodiments, rotation of the first actuation element 1121 in a first rotational direction and rotation of it in a second rotational direction opposite to the first rotational direction may both be driven by the first motor 121, and it is only needed to change the direction of rotation of the first motor 121. However, in some embodiments, the first motor 121 is only used to drive the rotation of the first actuation element 1121 in the first rotational direction, and the rotation of the first actuation element 1121 in the second rotational direction is driven by a torsion spring. As shown in Figs. 19a and 19b, in these embodiments, the first actuation assembly 122 of the syringe driving mechanism 120 may comprise a torsion spring 1223. One end of the torsion spring 1223 may be fixedly connected with the housing 150, and the other end may be fixedly connected with another rotating element (e.g., the first actuation element 1221 or control element 124 mentioned later), so that when the first motor 121 drives the first actuation element 1221 to rotate in the first rotational direction, the torsion spring 1223 is torsionally loaded to accumulate elastic potential energy, and when needed, the torsion spring 1223 may release the elastic potential energy it has accumulated to drive the first actuation element 1221 to rotate in the second rotational direction opposite to the first rotational direction.

[0104] In the embodiment shown in Figs. 19a and 19b, the elastic potential energy accumulated by the torsion spring 1223 may be gradually released. For example, the torsion spring 1223 may first release a portion of the elastic potential energy to rotate the first actuation element 1221 in the second rotational direction from 180° to 90°, so as to insert the needle 220 of the syringe 200 into the injection site of the target; then, after the injection is completed, the torsion spring 1223 may release its remaining elastic potential energy to rotate the first actuation element 1221 in the second rotational direction from 90° to 0°, so as to withdraw the needle 220 of the syringe 200 from the injection site of the target. In this embodiment, both the insertion of the needle 220 of the syringe 200 into the injection site of the target and the withdrawal of the needle 220 of the syringe 200 from the injection site of the target are accomplished instantaneously by the torsion spring 1223 that has accumulated energy, which can greatly reduce the pain suffered by the patient during the insertion and withdrawal of the needle 22.

[0105] In other embodiments, the torsion spring 1223 may also release all of its elastic potential energy at one time. For example, when the first motor 121 drives the first actuationelement 1221 to rotate in the first rotational direction, the needle 220 of the syringe 200 is inserted into the injection site of the target and the torsion spring 1223 accumulates elastic potential energy; after the injection is completed, the torsion spring 1223 may release all of its elastic potential energy at one time to rotate the first actuation element 1221 in the second rotational direction, thereby withdrawing the needle 220 of the syringe 200 from the injection site of the target.

[0106] In some embodiments, the first mating structure 1222 on the outer peripheral surface of the first actuation element 1221 of the syringe driving mechanism 120 and the second mating structure 1115 on the inner peripheral surface of the mating component 1113 of the syringe loading mechanism 110 may have configurations other than slots and protrusions. For example, the first mating structure 1222 may be configured as a first threaded structure and the second mating structure 1115 may be configured as a second threaded structure that is meshed with the first threaded structure. It is also possible to contemplate the first and second mating structures in other forms.

[0107] With continued reference to Figs. 5-7 and Figs. 19a to 26, in some embodiments, the syringe driving mechanism 120 may also comprise a locking mechanism 123. When the locking mechanism 123 is locked, the first actuation element 1221 cannot be rotated, and when the locking mechanism 123 is unlocked, the first actuation element 1221 can be rotated. The locking mechanism 123 may have a variety of suitable configurations. In the embodiment shown in Figs. 19a to 26, the locking mechanism 123 may comprise a control element 124, a locking element 125, at least one elastic element 126, and an unlocking element 127.

[0108] The control element 124 may be fixedly connected, via a shaft element 1241 extending in an axial direction, with the first actuation element 1221 in a way so that they are spaced apart from each other. The control element 124 may comprise at least one through-hole 1242 extending in an axial direction and at least one key pin 1243 arranged in a first portion of the at least one through-hole. The key pin 1243 is spring loaded such that a first end 1244 of the key pin 1243 protrudes from a corresponding through-hole 1242 in a locked state of the locking mechanism 123.

[0109] The locking element 125 may be provided between the first actuation element 1221 and the control element 124 and comprise at least one locking bar 1251 extending in an axial direction. The locking element 125 is movable in the axial direction such that in the locked state of the locking mechanism 123 the at least one locking bar 1251 is inserted into a second portion of the at least one through-hole 1242 of the control element 124. The at least onelocking bar 1251 of the locking element 125 may be pushed into the second portion of the at least one through-hole 1242 of the control element 124 by causing the at least one elastic element 126 (four elastic elements 126 as shown in Figs. 19b and 22c) to urge the locking element 125. As shown in Figs. 19b and 22c, each elastic element 126 may be configured as a spring that can be axially extended and compressed. A first end of each elastic element 126 may abut against a support element (e.g., a support element in the housing 150), and the other end thereof may abut against the locking element 125 and urge the locking element 125 towards the control element 124.

[0110] The unlocking element 127 may be configured to press the first end 1244 of the key pin 1243 back into the corresponding through-hole 1242, so that a second end of the key pin 1243, opposite to the first end 1244, can push the at least one locking bar 1251 of the locking element 125 out of the corresponding through-hole 1242, thereby achieving unlocking of the locking mechanism 123.

[0111] In some embodiments, the control element 124 may comprise two through-holes 1242 spaced apart from each other by 180° and two key pins 1243 respectively arranged within first portions of the two through-holes 1242. Correspondingly, the locking element 125 may comprise two locking bars 1251 spaced apart from each other by 180°, each locking bar 1251 being insertable into the second portion of a corresponding one of the through-holes 1242. In other embodiments, as shown in Figs. 23a-25, the control element 124 may comprise four through-holes 1242 spaced apart from each other by 90° and two key pins 1243 correspondingly arranged within first portions of two of the four through-holes which are spaced apart from each other by 180°. Correspondingly, as shown in Figs. 22a to 22c, the locking element 125 may comprise four locking bars 1251 spaced apart from each other by 90°, each locking bar 1251 being insertable into the second portion of a corresponding one of the through-holes 1242. Such a configuration, in combination with the four slots provided on the outer peripheral surface of the first actuation element 1221, allows to insert or withdraw the needle 220 of the syringe 200 into or from the injection site of the target by rotating the first actuation element 1221 by 90°, thereby significantly increasing the speed of needle insertion and needle withdrawal, so it can reduce the pain of the user or improve the user experience.

[0112] In some embodiments, as shown in Fig. 26, the unlocking element 127 may be connected to the first motor 121 and can be rotated under the drive of the first motor 121. When the unlocking element 127 is rotated to the position of the key pin 1243, the unlockingelement 127 can press the key pin 1243 back into a corresponding through-hole 1242. To facilitate pressing of the key pin 1243 by the unlocking element 127, the first end 1244 of the key pin 1243 may have a surface that tapers in a direction from the second end to the first end (e.g., a wedge-shaped or mushroom- shaped surface). In some embodiments, the unlocking element 127 is also configured to push the control element 124 and thus push the first actuation element 1221 to rotate. To this end, the control element 124 may also comprise at least one push portion 1245 adapted to cooperate with the unlocking element 127. After the unlocking element 127 unlocks the locking mechanism 123, the unlocking element 127 can rotate the control element 127 via the at least one push portion 1245, and thus rotate the first actuation element 1221. In the embodiment shown in Figs. 23a to 25, the control element 124 comprises two push portions 1245 adapted to cooperate with the unlocking element 127. The two push portions 1245 are configured in the form of bosses and are spaced apart from each other by 180°. The unlocking element 127 may comprise two portions adapted to abut and push the two push portions 1245 simultaneously. As shown in Fig. 26, the unlocking element 127 may be configured in an elongated shape, which may comprise two elongated portions symmetrical with respect to a shaft 1211 of the first motor 121, and each elongated portion may abut one push portion 1245.

[0113] In the embodiment described above with reference to Figs. 5 to 7 and Figs. 19a to 26, the first actuation assembly 122 of the syringe driving mechanism 120 moves the syringe loading mechanism 110 through rotation of a rotating element (e.g., first actuation element 1221) that the first actuation assembly comprises. However, the present disclosure is not limited to this. The first actuation assembly 122 of the syringe driving mechanism 120 may also move the syringe loading mechanism 110 via a translating element. For example, the first actuation assembly 122 may comprise a screw and a translating element provided on the screw, and the translating element may be fixedly connected with a mating component of the syringe loading mechanism 110. When the screw of the first actuation assembly 122 is rotated, the translating element may move axially along the screw and thus move the syringe loading mechanism 110 via the mating component.

[0114] In one embodiment according to the present disclosure, the entire working process of the syringe driving mechanism 120 as shown in Figs. 19a to 19b may comprise the following steps:

[0115] 1. A step in which the torsion spring 1223 accumulates energy: after the syringe200 is loaded, the first motor 121 drives the torsion spring 1223 and the first actuation element1221 simultaneously to rotate in a first rotational direction from 0° to 90°, thereby pretightening the torsion spring 1223 by 90°, and in this process, the at least one protrusion slides within a first slot of the four slots to drive the syringe loading mechanism 110 to move in a first translational direction; then, the first motor 121 continues to drive the torsion spring 1223 and the first actuation element 1221 to rotate from 90° to 180° in the first rotational direction, thereby pre-tightening the torsion spring 1223 by 180°, and in this process, the at least one protrusion slides within a second slot of the four slots, which is adjacent to the first slot, to drive the syringe loading mechanism 110 to move in a second translational direction opposite to the first translational direction, thereby achieving energy accumulation of the torsion spring 1223. In the step in which the torsion spring 1223 accumulates energy, the syringe driving mechanism 120 idles without inserting the needle of the syringe 200 into the injection site of the target or withdrawing the needle of the syringe 200 from the injection site of the target.

[0116] 2. A step in which the torsion spring 1223 releases the energy (elastic potential energy) it has accumulated in two steps to achieve needle insertion and needle withdrawal, respectively:

[0117] After the torsion spring 1223 has accumulated energy, the first motor 121 rotates the unlocking element 127 to rotate by 90° in a second rotational direction opposite to the first rotational direction, so that the unlocking element 127 reaches the first end 1244 of the key pin 1243 and presses the first end 1244 into the through-hole 1242, thereby separating the locking element 125 from the control element 124 and thus triggering a first unlocking of the control element 124 from the locking element 125.

[0118] After the first unlocking, the torsion spring 1223, with the energy it has accumulated, drives the control element 124 and thus drives the first actuation element 1221 to rotate in the second rotational direction from 180° to 90°, such that the at least one protrusion slides reversely in the second slot of the four slots to drive the syringe loading mechanism 110 to move in the first translational direction, thereby inserting the needle 220 of the syringe 200 into the injection site of the target; when the torsion spring 1223 is rotated to 90°, the four locking bars 1251 of the locking element 125 are inserted into the four through-holes 1242 of the control element 124 again, so that the locking element 125 and the control element 124 are locked again, at which time drug can be injected using the second motor 131 (to be described later) of the dose control mechanism 130.

[0119] After the injection is completed, the unlocking element 127 is driven to rotate again by the first motor 121, so that the unlocking element 127 reaches the first end 1244 of the keypin 1243 again and presses the first end 1244 into the through-hole 1242, thereby separating the locking element 125 from the control element 124 and thus triggering a second unlocking of the control element 124 from the locking element 125.

[0120] After the second unlocking, the torsion spring 1223, with the energy it has accumulated, continues to drive the control element 124 and thus drive the first actuation element 1221 to rotate in the second rotational direction from 90° to 0°, such that the at least one protrusion slides reversely within the first slot of the four slots to drive the syringe loading mechanism 110 to move in the second translational direction, thereby withdrawing the needle 220 of the syringe 200 from the injection site of the target.

[0121] Next, referring to Figs. 8 and Figs. 27 to 29, the dose control mechanism 130 of the automatic injection device 100 according to an embodiment of the present disclosure will be described. The dose control mechanism 130 may comprise a second motor 131 and a second actuation assembly 132. The second motor 131 may be a servo motor or a stepper motor. The second actuation assembly 132 is capable of moving the movable element 230 of the syringe 200 towards the first end of the cartridge 210 of the syringe 200 under the drive of the second motor 131, so as to expel a predetermined dose of fluid from the cartridge of the syringe and inject it into the injection site of the target.

[0122] The second actuation assembly 132 of the dose control mechanism 130 may comprise a screw 1321 and a second actuation element 1322 sleeved on the screw 1321. The second actuation element 1322 may comprise an urging portion 1323 adapted to urge the movable element 230 of the syringe 200. The screw 1321 can be rotated in either of a first rotational direction and a second rotational direction opposite to the first rotational direction under the drive of the second motor 131. When the screw 1321 is rotated in the first rotational direction, the second actuation element 1322 can be translated on the screw towards the first end of the cartridge 210 of the syringe to translate the movable element 230 of the syringe 200 towards the first end of the cartridge 210 via the urging portion 1323. When the screw 1322 is rotated in the second rotational direction, the second actuation element 1322 can be translated on the screw away from the first end of the cartridge 210 of the syringe, so as to return to its initial position.

[0123] When the movable element 230 of the syringe 200 comprises a plunger rod 2302, the urging portion 1323 of the second actuation element 1322 may be configured as a flat element suspended from the screw 1322. The flat element may urge an end of the plunger rod 2302 (as shown in Fig. 28) to move the plunger rod. In some embodiments, the movableelement 230 of the syringe 200 may not comprise plunger rod 2302. In this case, the urging portion 1323 of the second actuation element 1322 may be configured to directly urge the stopper 2301 to move the stopper. For example, the urging portion 1323 of the second actuation element 1322 may comprise “L” shaped first and second branches, and one branch of the urging portion 1323 parallel to the screw 1322 may extend directly into the cartridge 210 of the syringe 200 to move the stopper 2301.

[0124] Referring to Figs. 30a to 30c, in some embodiments, the automatic injection device 100 may comprise a catch element 160 for the shield cap 240 of the syringe 200. The catch element 160 can be sleeved on an outer periphery of the shield cap 240 and can remove the shield cap 240 from the syringe 200 to expose the needle 220. To this end, the catch element 160 may comprise two or more circumferentially distributed elastic fingers 161. The free end of each elastic finger 161 may comprise a hook portion 162 extending radially inward. When the catch element 160 is sleeved on the outer periphery of the shield cap 240, the hook portion 162 of the catch element 160 can hook an outer end face of the shield cap 240. In this way, when the catch element 160 is removed from the syringe 200, the shield cap 240 can also be removed from the syringe 200 at the same time. In some embodiments, the housing 150 comprises an opening 151 for the syringe retainer 112 to protrude. At least a portion of the catch element 160 can be inserted into the opening 151 (as shown in Fig. 10a). In the case where the coupling mechanism 113 of the syringe loading mechanism 110 is configured as a push-press type elastic self-locking mechanism, the push-press type elastic self-locking mechanism can be coupled and decoupled by pressing the catch element 160.

[0125] The provision of the catch element 160 can make it easier to operate the automatic injection device 100 according to the present disclosure. For example, as shown in Fig. 4, when loading the syringe 200 onto the syringe loading mechanism 110, the catch element 160 may be first sleeved on the outer periphery of the shield cap 240 of the syringe 200, and then the syringe 200, on which the catch element 160 is mounted, may be loaded onto the syringe holder 112 of the syringe loading mechanism 110. After that, the syringe holder 112 may be pushed into the housing 150 and the syringe holder 112 and the base 111 may be coupled to each other by pushing the catch element 160. For another example, as shown in Fig. 9, when performing an injection, the shield cap 240 of the syringe 200 may be removed from the syringe 200 firstly by pulling the catch element 160, thus exposing the needle 220. After the shield cap 240 is removed from the syringe 200, the shield cap 240 may be held in the catch element 160. The catch element 160 and the shield cap 240 it holds can be placed upright in aplane so as to help prevent the shield cap 240 from rolling to somewhere else. Then, the needle 220 of the syringe 200 is inserted into the injection site of the target by the syringe driving mechanism 120 and the fluid within the cartridge 210 of the syringe 200 is injected into the injection site of the target by the dose control mechanism 110. After the injection is completed and the needle 220 is withdrawn from the injection site of the target, in order to remove the used syringe 200 from within the housing 150 of the automatic injection device 100, the catch element 160 holding the shielding cap 240 may be remounted to the needle 220 of the syringe 200, and then the syringe holder 112 may be decoupled from the base 111 and the syringe holder 112 may be ejected from the housing 150 by pushing the catch element 160. The used syringe 200 may then be removed from the catch element 160 and discarded into a recycle container.

[0126] In short, the catch element 160 may assist a user in easily loading the syringe 200 into the syringe loading mechanism 110 of the automatic injection device 100 prior to injection and easily removing a used syringe 200 after injection. In addition, with the aid of the catch element 160, it is also possible to easily remove the shield cap 240 of the needle 220 before injection and safely position the shield cap 240 during injection; after injection, the shield cap 240 can be easily remounted onto the used syringe 200 to minimize needle stick injury.

[0127] Returning to Fig. 1, as previously described, the automatic injection device 100 according to the present disclosure may comprise the control unit 140. The control unit 140 may control at least the first motor 121 of the syringe driving mechanism 120 and the second motor 131 of the dose control mechanism 130. For example, the control unit 140 may control at least one of start, stop, operation duration, rotation direction, rotation speed, rotation angle and rotation frequency of the first motor 121 and the second motor 131 to perform more precise control of the first motor 121 and the second motor 131. The control unit 140 may receive a user instruction to perform control. In some cases, the housing 150 of the automatic injection device 100 may comprise a user interface 155. The user interface 155 may comprise at least one of a display screen and buttons such that the user can set operating parameters of the automatic injection device 100 or input user instructions. In some cases, it is possible to set the operating parameters of the automatic injection device 100 or input user instructions through a cell phone APP, and the control unit 140 receives a control signal from the cell phone APP to implement control.

[0128] Fig. 31 is a schematic time sequence diagram of synergized control of the first motor 121 of the syringe driving mechanism 120 and the second motor 131 of the dose controlmechanism 130 by the control unit 140 according to one embodiment of the present disclosure. In this embodiment, the control unit 140 may perform the following control: 1) in step 1401, the control unit 140 may control the first motor 121 to rotate in a first rotational direction from 0° to 180° to achieve energy accumulation of the torsion spring 1223; 2) in step 1402, the control unit 140 may hold the first motor 121 at the 180° position and hold the torsion spring 1223 that has accumulated energy until the control unit 140 receives an instruction to prepare the insertion of the needle 220 of the injector 200 into the injection site of the target; 3) in step 1403, the control unit 140 may control the first motor 121 to rotate in a second rotational direction opposite to the first rotational direction from 180° to 90°, at which time a first unlocking of the locking element 125 and the control element 124 is achieved, so that the torsion spring 1223, with the energy it has accumulated, instantaneously inserts the needle 220 of the injector 200 into the injection site of the target; 4) after the needle 220 of the injector 200 is inserted into the injection site of the target, in step 1404, the control unit 140 may hold the first motor 121 at the 90° position and at the same time control the second motor 131 of the dose control mechanism 130 to rotate to perform an injection; 5) when the injection is completed, in step 1405, the control unit 140 may control the first motor 121 to rotate in the second rotational direction from 90° to 0° while holding the second motor 131 of the dose control mechanism 130 at the position where it is located just after the completion of the injection, at which time a second unlocking of the locking element 125 and the control element 124 is achieved, so that the torsion spring 1223, with the energy it has accumulated, instantaneously withdraws the needle 220 of the injector 200 from the injection site of the target; and 6) after the needle 220 of the injector 200 is withdrawn from the injection site of the target, the control unit 140 may control the second motor 131 of the dose control mechanism 130 to reversely rotate to its initial position in step 1406. In the above-mentioned steps, the control unit 140 may control at least one of start, stop, operation time length, rotation direction, rotation speed, rotation angle and rotation frequency of the first motor 121 and the second motor 131 according to actual conditions or user settings, to perform more precise control of the first motor 121 and the second motor 131.

[0129] In some embodiments, the automatic injection device 100 further comprises a power supply element 170 for providing power to the first motor 121 and the second motor 131. The power supply element 170 may be a disposable battery or a rechargeable battery. When the power supply element 170 is a rechargeable battery, the housing 150 of the automatic injection device 100 may be provided with a power port 152 to charge the power supplyelement 170. In some embodiments, the automatic injection device 100 may also not comprise a separate power supply element. In the case where the automatic injection device 100 does not comprise a power supply element, external power may be supplied to the first motor 121, the second motor 131, the control unit 140 and other components through different types of power port 152.

[0130] In some embodiments, the housing 150 of the automatic injection device 100 may comprise a contact sensor 153 for detecting whether the automatic injection device 100 is in contact with the injection site of the target. The control unit 140 may receive a signal from the contact sensor 153 and determine whether to perform a subsequent operation. In some embodiments, the housing 150 of the automatic injection device 100 may also comprise an indicating light 154 for indicating the operating status of the automatic injection device. The indicating lights 154 may emit light of different colors to indicate different operating statuses.

[0131] The automatic injection device 100 according to the present disclosure can achieve automation of some key injection steps, e.g., it can achieve automation of at least some or all of the steps of needle insertion, dose dispensing, and needle withdrawal, so it can provide a standardized injection procedure and simplified operation for users. In embodiments in which a catch element 160 is included, the automatic injection device 100 according to the present disclosure may also achieve easy loading and removal of the syringe, and allow the needle 220 of the syringe 200 to be always shielded during the loading and removal, thereby minimizing needle stick injury. With the aid of the syringe driving mechanism 120, the automatic injection device 100 according to the present disclosure may achieve faster needle insertion speed and / or needle withdrawal speed than conventional mechanical driving mechanisms, so that the user’s pain can be reduced, and user experience can be improved. In addition, the automatic injector device 100 according to the present disclosure may also be reused for a long time, thereby saving costs.

[0132] Although exemplary embodiments of the present disclosure have been described, those skilled in the art should understand that various variations and changes can be made to the exemplary embodiments of the present disclosure without materially departing from the spirit and scope of the present disclosure. Accordingly, all such variations and changes are included within the protection scope of the present disclosure as defined in the claims. The present disclosure is defined by the appended claims, with equivalents of the claims also included therein.

Claims

WHAT IS CLAIMED IS:

1. An automatic injection device for automatically injecting a fluid in a syringe to an injection site of a target, the syringe comprising a cartridge for containing a fluid, a needle provided at a first end of the cartridge, and a movable element movable within the cartridge, the movable element capable of being driven towards the first end of the cartridge to inject the fluid within the cartridge into the injection site of the target via the needle, wherein the automatic injection device comprises: a syringe loading mechanism for loading and fixing the syringe; a syringe driving mechanism comprising a first motor and a first actuation assembly, the first actuation assembly capable of moving the syringe loading mechanism in a first translational direction towards the injection site of the target under a drive of the first motor to insert the needle of the syringe fixed to the syringe loading mechanism into the injection site of the target; and a dose control mechanism comprising a second motor and a second actuation assembly, the second actuation assembly capable of moving the movable element of the syringe towards the first end of the cartridge under a drive of the second motor so as to expel a predetermined dose of fluid from the cartridge of the syringe and inject it into the injection site of the target.

2. The automatic injection device according to claim 1, wherein the automatic injection device further comprises a housing, the syringe loading mechanism is located within the housing and comprises: a base having a body extending along a longitudinal direction, wherein the longitudinal direction is parallel to the first translational direction; a syringe holder for loading and fixing the syringe, wherein the syringe holder comprises a recess for accommodating the syringe and a fixing element for fixing the cartridge of the syringe, and wherein the syringe holder is movable along the longitudinal direction relative to the base between a first position in which the syringe holder protrudes from the housing to facilitate loading and fixing the syringe and a second position in which the syringe holder is retracted into the housing; and a coupling mechanism configured to releasably couple the syringe holder to the base when the syringe holder is in the second position.

3. The automatic injection device according to claim 2, wherein a second end of the cartridge of the syringe, opposite to the first end, comprises a radially outwardly extending flange, and the fixing element of the syringe holder is configured as a cutout adapted to receive and position the flange to prevent the cartridge of the syringe from moving in the longitudinal direction.

4. The automatic injection device according to claim 2, wherein the coupling mechanism is configured as a push-press type elastic self-locking mechanism comprising at least one first engagement element provided on the syringe holder and at least one second engagement element provided on the body of the base, wherein the first engagement element and the second engagement element are coupled to each other when the push-press type elastic self-locking mechanism is subjected to an urging force for a first time, and the first engagement element and the second engagement element are decoupled when the push-press type elastic self-locking mechanism is subjected to an urging force for a second time.

5. The automatic injection device according to claim 2, wherein the first actuation assembly of the syringe driving mechanism comprises a first actuation element in a cylindrical shape, the first actuation element being rotatable under the drive of the first motor and provided with a first mating structure on an outer peripheral surface thereof, wherein the syringe loading mechanism comprises a mating component for mating with the first actuation element, the mating component comprising a cylindrical inner cavity for receiving the first actuation element and a second mating structure provided on an inner peripheral surface of the cylindrical inner cavity, and wherein when the first actuation element is rotated within the cylindrical inner cavity of the mating component, the first mating structure and the second mating structure cooperate with each other such that the first actuation element is at least capable of driving the syringe loading mechanism to move in the first translational direction, to insert the needle into the injection site of the target.

6. The automatic injection device according to claim 5, wherein the first actuation element is rotatable in a first rotational direction, and when the first actuation element is rotated in the first rotational direction within the cylindrical inner cavity of the mating component, the first mating structure and the second mating structure cooperate with each other such thatthe first actuation element drives the syringe loading mechanism to move in the first translational direction to insert the needle into the injection site of the target, and wherein the first actuation element is also rotatable in a second rotational direction opposite to the first rotational direction, and when the first actuation element is rotated in the second rotational direction within the cylindrical inner cavity of the mating component, the first mating structure and the second mating structure cooperate with each other such that the first actuation element drives the syringe loading mechanism to move in a second translational direction opposite to the first translational direction, to withdraw the needle from the injection site of the target.

7. The automatic injection device according to claim 6, wherein rotation of the first actuation element in the first rotational direction and rotation of the first actuation element in the second rotational direction are both driven by the first motor.

8. The automatic injection device according to claim 6, wherein the syringe driving mechanism comprises a torsion spring, rotation of the first actuation element in the first rotational direction is driven by the first motor, and rotation of the first actuation element in the second rotational direction is driven by the torsion spring, wherein when the first motor drives the first actuation element to rotate in the first rotational direction, the torsion spring is torsionally loaded to accumulate elastic potential energy.

9. The automatic injection device according to claim 6, wherein the first mating structure is configured as at least one slot extending helically along an outer peripheral surface of the first actuation element from a first end of the first actuation element to a second end of the first actuation element, and wherein the second mating structure is configured as at least one protrusion which can be received in and reciprocally slide along the at least one slot to selectively drive the syringe loading mechanism to move in one of the first and second translational directions.

10. The automatic injection device according to claim 5, wherein the first mating structure is configured as four slots provided on an outer peripheral surface of the first actuation element, each slot extending helically from the first end of the first actuation element to the second end of the first actuation element, wherein the four slots are evenly distributed on the outer peripheral surface of the first actuation element such that each slot extends alongthe outer peripheral surface of the first actuation element by 90°, and the four slots are connected end to end such that adjacent two slots are mirror images of each other, and wherein the second mating structure is configured as at least one protrusion which can sequentially slide along two adjacent slots of the four slots, to drive the syringe loading mechanism to move alternately in the first translational direction and a second translational direction opposite to the first translational direction.

11. The automatic injection device according to claim 10, wherein the at least one protrusion is configured as two protrusions spaced apart from each other by 180°, the two protrusions are respectively accommodated in two of the four slots, which are spaced apart from each other by 180°, and each protrusion is capable of sequentially slide along corresponding two adjacent slots of the four slots to drive the syringe loading mechanism to move alternately in the first and second translational directions.

12. The automatic injection device according to claim 10, wherein when the first actuation element rotates in the first rotational direction from 0° to 90°, the at least one protrusion slides within a first slot of the four slots to drive the syringe loading mechanism to move in the first translational direction, and when the first actuation element continues to rotate in the first rotational direction from 90° to 180°, the at least one protrusion slides within a second slot of the four slots which is adjacent to the first slot to drive the syringe loading mechanism to move in the second translational direction; and wherein when the first actuation element is rotated in the second rotational direction opposite to the first rotational direction from 180° to 90°, the at least one protrusion slides reversely within the second slot of the four slots to drive the syringe loading mechanism to move in the first translational direction, and when the first actuation element continues to rotate in the second rotational direction from 90° to 0°, the at least one protrusion slides reversely within the first slot of the four slots to drive the syringe loading mechanism to move in the second translational direction.

13. The automatic injection device according to claim 12, wherein the syringe driving mechanism comprises a torsion spring, rotation of the first actuation element in the first rotational direction is driven by the first motor, and rotation of the first actuation element in the second rotational direction is driven by the torsion spring, wherein when the first motordrives the first actuation element to rotate in the first rotational direction, the torsion spring is torsionally loaded to accumulate elastic potential energy.

14. The automatic injection device according to claim 5, wherein the syringe driving mechanism further comprises a locking mechanism, wherein the first actuation element is not rotatable when the locking mechanism is locked, and the first actuation element is rotatable when the locking mechanism is unlocked.

15. The automatic injection device according to claim 14, wherein the locking mechanism comprises: a control element, which is fixedly connected, via a shaft element extending in an axial direction, with the first actuation element in a way so that they are spaced apart from each other, wherein the control element comprises at least one through- hole extending in the axial direction and at least one key pin provided in a first portion of the at least one through-hole, the key pin is spring-loaded such that a first end of the key pin protrudes from the respective through-hole in a locked state of the locking mechanism; a locking element provided between the first actuation element and the control element and comprising at least one locking bar extending along the axial direction, wherein the locking element is movable in the axial direction such that in the locked state of the locking mechanism, the at least one locking bar is inserted into a second portion of the at least one through-hole of the control element; at least one elastic element that urges the locking element to push the at least one locking bar of the locking element into the second portion of the at least one through- hole of the control element; and an unlocking element configured to press the first end of the key pin back into the respective through-hole such that a second end of the key pin opposite to its first end can push the at least one locking bar of the locking element out of the respective through-hole, thereby achieving unlocking of the locking mechanism.

16. The automatic injection device according to claim 15, wherein the control element comprises two through-holes spaced apart from each other by 180° and two key pins respectively provided in first portions of the two through-holes, and the locking elementcomprises two locking bars spaced apart from each other by 180°, each locking bar being insertable into a second portion of a corresponding one of the two through-holes.

17. The automatic injection device according to claim 15, wherein the control element comprises four through-holes spaced apart from each other by 90° and two key pins respectively provided in first portions of two of the four through-holes, which are spaced apart from each other by 180°, and the locking element comprises four locking bars spaced apart from each other by 90°, each locking lever being insertable into a second portion of a corresponding one of the four through-holes.

18. The automatic injection device according to claim 15, wherein the unlocking element is connected to the first motor and can be rotated under the drive of the first motor, and the control element further comprises at least one push portion adapted to mate with the unlocking element, and after the unlocking element unlocks the locking mechanism, the unlocking element can also rotate the control element via the at least one push portion and thus rotate the first actuation element.

19. The automatic injection device according to claim 18, wherein the control element comprises two push portions adapted to mate with the unlocking element, the two push portions are configured in the form of bosses and spaced apart from each other by 180°, and the unlocking element comprises two portions adapted to abut and push the two push portions simultaneously.

20. The automatic injection device according to claim 1, wherein the second actuation assembly of the dose control mechanism comprises a screw and a second actuation element sleeved on the screw, the second actuation element comprising an urging portion adapted to urge the movable element of the syringe, wherein the screw can be rotated in either of a first rotational direction and a second rotational direction opposite to the first rotational direction under the drive of the second motor, and when the screw is rotated in the first rotational direction, the second actuation element is translated on the screw towards the first end of the cartridge to translate the movable element of the syringe towards the first end of the cartridge via the urging portion.

21. The automatic injection device according to claim 20, wherein the movable element of the syringe comprises a plunger rod, the urging portion of the second actuation element being adapted to push an end of the plunger rod.

22. The automatic injection device according to claim 20, wherein the syringe comprises a shield cap for shielding the needle, and the automatic injection device comprises a catch element for the shield cap, the catch element can be sleeved on an outer periphery of the shield cap and can remove the shield cap from the syringe to expose the needle.

23. The automatic injection device according to claim 22, wherein the catch element comprises two or more circumferentially distributed elastic fingers, a free end of each elastic finger comprising a hook portion extending radially inward, and when the catch element is sleeved on the outer periphery of the shield cap, the hook portion hooks an outer end face of the shield cap to enable removal of the shield cap from the syringe.

24. The automatic injection device according to claim 23, wherein the housing comprises an opening for the syringe holder to protrude, at least a portion of the catch element can be inserted into the opening, and wherein the coupling mechanism is configured as a pushpress type elastic self-locking mechanism which can be coupled and decoupled by pressing the catch element.

25. The automatic injection device according to claim 1, wherein the automatic injection device comprises a control unit for controlling at least one of start, stop, operation duration, rotation direction, rotation speed, rotation angle and rotation frequency of the first motor and the second motor.

26. The automatic injection device according to claim 25, wherein the automatic injection device further comprises a power supply element for providing power to the first motor and the second motor.

27. The automatic injection device according to claim 26, wherein the housing of the automatic injection device comprises at least one of:a contact sensor for detecting whether the automatic injection device is in contact with the injection site of the target; an indicating light for indicating an operating status of the automatic injection device; a power port for supplying external power to the first motor, the second motor and the control unit, or charging the power supply element when the power supply element is a rechargeable battery; a user interface comprising at least one of a display screen and a button such that a user can set operating parameters of the automatic injection device or input user instructions.

28. The automatic injection device according to claim 1, wherein the first motor is a servo motor or a stepper motor, and wherein the second motor is a servo motor or a stepper motor.

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