Syringe drive mechanism and injection device

Abstract

This application relates to the field of medical device technology, providing a syringe driving mechanism and injection device. The syringe driving mechanism includes a housing assembly, a clutch assembly, an adjusting assembly, a numerical rotating cylinder, a reset component, a push rod assembly, and a memory component. A third limiting part is used to limit the clockwise rotation stroke of the memory component. After the scale adjustment is completed, when the memory component is limited to the third limiting part of the push rod assembly in the clockwise direction, the adjusting assembly cannot continue to rotate clockwise relative to the clutch assembly. After the injection is completed, the numerical rotating cylinder rotates counterclockwise to the second limiting part, preventing the adjusting assembly from rotating counterclockwise. This indicates that the medication in the vial assembly has been completely injected. Therefore, after the medication is used up, the adjusting assembly self-locks, preventing further scale adjustments and injections, thus reducing the risk of accidental injection after the medication in the vial assembly has run out.

Description

Technical Field

[0001] This application belongs to the field of medical device technology, and more specifically, relates to a syringe driving mechanism and injection device. Background Technology

[0002] Insulin pens are common medical tools for injecting insulin and are widely used by diabetic patients. Patients at different stages of diabetes require different doses of insulin and related medications, and long-term injections are necessary. To save resources, some insulin pens on the market offer adjustable dosages for multiple injections. Specifically, when an injection is needed, the scale on the insulin pen is adjusted to the required dosage, and then that dosage is injected. When the next injection is needed, the needle is replaced, the scale on the pen is readjusted to the required dosage, and then that dosage is injected.

[0003] In related technologies, the markings on the insulin pen can still be adjusted even after all the medication in the pen has been used up. This means that after the insulin is completely depleted, the user might readjust the markings to perform an injection without medication, thus posing a risk of accidental injection.

[0004] The above statements are for the purpose of providing background information in relation to this application only and do not necessarily constitute prior art. Utility Model Content

[0005] One of the objectives of this application is to provide a syringe driving mechanism and injection device that can improve the problem of accidental injection.

[0006] To solve the above-mentioned technical problems, the technical solution adopted in the embodiments of this application is as follows:

[0007] In a first aspect, embodiments of this application provide a syringe driving mechanism applied to an injection device, wherein the two ends of the injection device along the axial direction are a proximal end and a distal end, respectively; the syringe driving mechanism includes:

[0008] A housing assembly for connection with a medicine bottle assembly, the housing assembly having a first limiting part and a second limiting part;

[0009] The clutch assembly is located inside the housing assembly and is circumferentially limited and engaged with the first limiting part, and is configured to disengage from the first limiting part under the action of a first external force;

[0010] The adjustment component is rotatably disposed within the housing assembly and configured to be limited to the clutch assembly in a counterclockwise direction, and is also configured to be rotatable relative to the clutch assembly under the action of a second external force;

[0011] A numerical rotary drum is rotatably threaded into the housing assembly; the numerical rotary drum is sleeved outside the adjustment assembly and circumferentially limited on the adjustment assembly, and is configured to move axially relative to the housing assembly and the adjustment assembly as it rotates with the adjustment assembly to adjust the scale;

[0012] A reset member is connected between the housing assembly and the adjustment assembly and is configured to provide the adjustment assembly with a driving force for rotation in a counterclockwise direction so that the numerical rotary drum is limited to the second limiting part in a counterclockwise direction;

[0013] A push rod assembly, threaded to the housing assembly and circumferentially limited to the clutch assembly, is configured to move distally relative to the housing assembly and the clutch assembly when rotated counterclockwise to drive the medicine in the vial assembly;

[0014] The memory element is threadedly connected to the push rod assembly and circumferentially limited within the adjustment assembly, and is configured to move axially relative to the adjustment assembly and the push rod assembly when rotating relative to the push rod assembly; the push rod assembly is provided with a third limiting part, which is used to limit the rotational stroke of the memory element in the clockwise direction.

[0015] In some embodiments, the clutch assembly has a plurality of ratchet teeth arranged circumferentially at one end toward the proximal end, and the ratchet teeth are inclined in a clockwise direction;

[0016] The adjustment components include:

[0017] The adjustment body is rotatably disposed within the housing assembly and is located at the proximal end of the clutch assembly; the numerical rotary drum is sleeved outside the adjustment body, the adjustment body is connected to the reset component, and is respectively circumferentially limited to the numerical rotary drum and the memory component;

[0018] The elastic tooth is provided on the adjusting body and extends outward from the adjusting body at the distal end; the elastic tooth elastically engages between two adjacent ratchet teeth, so as to be limited to the ratchet teeth in the counterclockwise direction, and is used to elastically move relative to the ratchet teeth in the clockwise direction under the action of a second external force.

[0019] In some embodiments, the regulating body includes:

[0020] The first adjusting component is circumferentially limited to the memory component;

[0021] The second adjusting member is sleeved outside the first adjusting member; the elastic tooth is provided on the second adjusting member, the second adjusting member is connected to the reset member, the numerical rotating cylinder is sleeved outside the second adjusting member, and is circumferentially limited to cooperate with the second adjusting member;

[0022] The first adjusting member and the second adjusting member are provided with a buckle and the other is provided with a groove. The buckle is limited in the groove in the circumferential and axial directions, and in the circumferential direction, the size of the groove is larger than the size of the buckle. The first adjusting member is configured to drive the elastic teeth to move elastically away from the ratchet teeth when rotating counterclockwise relative to the second adjusting member under the action of the second external force.

[0023] In some embodiments, the first adjusting member includes:

[0024] The first adjustment part is circumferentially limited and cooperates with the memory element. The second adjustment part is sleeved outside the first adjustment part. One of the first adjustment part and the second adjustment part is provided with a buckle, and the other is provided with a slot.

[0025] The second adjustment part is located at the distal end of the first adjustment part. The second adjustment part is provided with a relief groove extending through it along the axial direction. The elastic tooth extends out of the relief groove at the distal end. The groove wall of the relief groove is provided with a guide surface, which is configured to squeeze the elastic tooth when the first adjustment part rotates counterclockwise relative to the second adjustment part, so that the elastic tooth moves elastically away from the ratchet tooth.

[0026] In some embodiments, a first threaded groove is provided on the outer peripheral wall of the push rod assembly, and a third limiting portion is formed on the inner wall of the proximal end of the first threaded groove in the extending direction of the first threaded groove.

[0027] The memory element is sleeved on the outer periphery of the push rod assembly, and the inner peripheral wall of the memory element has a first thread, which engages with the first thread groove thread.

[0028] In some embodiments, the clutch assembly includes:

[0029] The rotating component is rotatably disposed within the housing assembly and sleeved outside the push rod assembly, and is circumferentially limited to the push rod assembly;

[0030] The clutch is sleeved on the outside of the push rod assembly and engages with the first limiting part in a circumferential limiting manner; the clutch is used to engage with the rotating part in a circumferential limiting manner.

[0031] The first elastic element abuts against the clutch element and the rotating element;

[0032] The adjusting component is axially movable within the housing assembly and is configured to move distally relative to the housing assembly under the action of a first external force to compress and drive the clutch to disengage from the first limiting portion.

[0033] In some embodiments, the rotating member and the clutch member are spaced apart, and the push rod assembly is configured to be rotatable relative to the housing assembly in a clockwise direction;

[0034] The rotating component is axially movable within the housing assembly and configured to move proximally under pressure from the vial assembly to engage with the clutch component in a circumferentially limited manner.

[0035] In some embodiments, the housing assembly includes:

[0036] The housing is used to connect with the medicine bottle assembly, and both the first limiting part and the second limiting part are provided on the housing;

[0037] The movable part is circumferentially limited on the housing and threadedly connected to the push rod assembly, and axially limited to the rotating part; the movable part is axially movable on the housing and is used to abut against the medicine bottle assembly at the distal end.

[0038] In some embodiments, the housing assembly further includes a fastener fixed to the housing, and a movable member circumferentially limited to the fastener, the fastener being used for detachably connecting the vial assembly.

[0039] Secondly, embodiments of this application provide an injection device, comprising:

[0040] Syringe drive mechanism;

[0041] A vial assembly, including a mounting bracket detachably mounted on a housing assembly and a vial detachably mounted on the mounting bracket;

[0042] The injection needle is detachably mounted on the mounting bracket and is connected to the vial.

[0043] The beneficial effects of the syringe driving mechanism and injection device provided in this application are as follows:

[0044] The syringe driving mechanism provided in this application embodiment, in use, first uses a second external force to drive the adjusting component to rotate clockwise relative to the clutch component. Based on the circumferential limiting fit between the adjusting component and the numerical cylinder, and between the memory component and the adjusting component, the numerical cylinder and the memory component rotate clockwise relative to the clutch component along with the adjusting component. This causes the memory component to move relative to the push rod assembly towards the third limiting part, and the numerical cylinder moves axially relative to the housing assembly and the adjusting component to achieve scale adjustment. Then, a first external force drives the clutch component to disengage from the first limiting part. The adjusting component rotates counterclockwise under the driving force of the reset component. Based on the counterclockwise limiting fit of the adjusting component on the clutch component, and the circumferential limiting fit between the clutch component and the push rod assembly, the numerical cylinder, memory component, clutch component, and push rod assembly all rotate counterclockwise relative to the housing assembly along with the adjusting component. During this process, the push rod assembly moves distally to drive the liquid in the vial assembly. Under the driving force of the reset component, when the numerical cylinder rotates counterclockwise with the adjusting component until it reaches the second limiting part, the adjusting component, clutch component, numerical cylinder, memory component, and push rod assembly all stop rotating counterclockwise, thus completing a single injection of the medicine. The push rod assembly has a third limiting part, which limits the clockwise rotation of the memory component. After the scale adjustment is completed, when the memory component is limited to the third limiting part of the push rod assembly in the clockwise direction, the adjusting component cannot continue to rotate clockwise relative to the clutch component, thus preventing further scale adjustment. After completing this injection, the numerical cylinder rotates counterclockwise until it reaches the second limiting part, preventing the adjusting component from rotating counterclockwise. Therefore, the push rod assembly cannot move further to the distal end to complete the injection. Since the push rod assembly's distal movement has been completed, the medicine in the vial assembly can be considered completely injected. Therefore, once the medication in the vial assembly is used up, the adjustment component locks itself, preventing further scale adjustments and injections, thus reducing the risk of accidental injection after the medication inside the vial assembly has run out.

[0045] The injection device provided in this application adopts the syringe driving mechanism involved in the above embodiments. After the medicine in the vial assembly is used up, the adjustment component is self-locked. The adjustment component cannot continue to rotate relative to the clutch component in the clockwise direction, nor can it rotate in the counterclockwise direction, so that the scale adjustment and injection work cannot continue. This can reduce the risk of accidental injection after the medicine in the vial assembly is used up.

[0046] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 Three-dimensional structural diagrams of the injection device provided in some embodiments of this application;

[0049] Figure 2 for Figure 1 decomposition Figure 1 ;

[0050] Figure 3 for Figure 1 decomposition Figure 2 ;

[0051] Figure 4 for Figure 1 A partial sectional view along AA;

[0052] Figure 5 A perspective structural view of the housing of the syringe drive mechanism provided in some embodiments of this application;

[0053] Figure 6 for Figure 5 A sectional view;

[0054] Figure 7 Partial structural diagrams of syringe drive mechanisms provided in some embodiments of this application;

[0055] Figure 8 A three-dimensional structural diagram of the numerical rotating cylinder of the syringe drive mechanism provided in some embodiments of this application;

[0056] Figure 9 A perspective structural diagram of the adjustment assembly of the syringe drive mechanism provided in some embodiments of this application;

[0057] Figure 10 Three-dimensional structure of the first adjusting member of the syringe driving mechanism provided in some embodiments of this application Figure 1 ;

[0058] Figure 11 A perspective structural diagram of the memory element of the syringe driving mechanism provided in some embodiments of this application;

[0059] Figure 12 A perspective structural view of the plunger assembly of the syringe drive mechanism provided in some embodiments of this application;

[0060] Figure 13 for Figure 12 Enlarged view of point B in the middle;

[0061] Figure 14 A perspective structural view of the clutch component of the syringe drive mechanism provided in some embodiments of this application;

[0062] Figure 15 Structural diagrams of the second adjusting member and elastic teeth of the syringe drive mechanism provided in some embodiments of this application;

[0063] Figure 16 Three-dimensional structure of the first adjusting member of the syringe driving mechanism provided in some embodiments of this application Figure 2 ;

[0064] Figure 17 for Figure 16 Enlarged view of point C in the middle;

[0065] Figure 18 A perspective structural view of the rotating component of the syringe drive mechanism provided in some embodiments of this application;

[0066] Figure 19 Structural diagrams of the push rod assembly and rotating component of the syringe drive mechanism provided in some embodiments of this application;

[0067] Figure 20 for Figure 4 Enlarged view of point D in the middle;

[0068] Figure 21 A partial cross-sectional view of a syringe drive mechanism without the vial assembly provided in some embodiments of this application;

[0069] Figure 22 A perspective structural view of the moving part of the syringe driving mechanism provided in some embodiments of this application;

[0070] Figure 23 This is a perspective structural view of the fixture of the syringe driving mechanism provided in some embodiments of this application.

[0071] The following are the labeling elements in the figure:

[0072] 100-Injector drive mechanism; 10-Housing assembly; 101-Window; 11-Housing; 111-First limiting part; 112-Second thread; 12-Moving part; 13-Fixing part; 14-Limiting part; 141-Second limiting part; 20-Clutch assembly; 21-Rotating part; 211-Protrusion; 212-Second gear tooth; 22-Clutch part; 221-Ratchet tooth; 222-Fourth limiting part; 223-First gear tooth; 23-First elastic element; 30-Adjusting assembly; 301-Slot; 302-Allowing groove; 303-Guide surface; 304-Second limiting groove; 31-Adjusting body; 311-First adjusting element; 3111-First adjusting part; 3112-Second adjusting part Section; 312-Second adjusting element; 3121-Snap fastener; 3122-First rib; 32-Elastic tooth; 40-Numerical rotary drum; 401-Second threaded groove; 402-First limiting groove; 50-Reset element; 60-Push rod assembly; 601-First threaded groove; 602-Slide groove; 61-Third limiting part; 70-Memory element; 71-First thread; 72-Second rib; 80-Knob; 90-Button; 110-Second elastic element; 200-Valve assembly; 210-Mounting bracket; 220-Valve; 230-Piston; 300-Injection needle; 400-Pen cap; a-Proximal end; b-Distal end; W-Circumferential direction; W1-Clockwise direction; W2-Counterclockwise direction; Y-Axial direction. Detailed Implementation

[0073] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0074] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0075] Unless otherwise specified, all technical features and optional technical features of the embodiments of this application can be combined with each other to form new technical solutions.

[0076] In the description of the embodiments of this application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0077] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0078] In the description of the embodiments of this application, "multiple" means two or more, and unless otherwise explicitly specified, "two or more" includes two. Correspondingly, "multiple groups" means two or more groups, including two groups.

[0079] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0080] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0081] The following detailed description is provided in conjunction with specific accompanying drawings and embodiments:

[0082] Please refer to the following: Figure 1 and Figure 2 , Figure 1 This is a perspective structural diagram of the injection device provided in some embodiments of this application. Figure 2 for Figure 1 decomposition Figure 1 The syringe drive mechanism 100 provided in this application embodiment is applied to an injection device, wherein the two ends of the injection device along the axial direction Y are a proximal end and b distal end, respectively.

[0083] The injection device may include a vial assembly 200 and an injection needle 300. The vial assembly 200 is mounted on the syringe drive mechanism 100, and the injection needle 300 is mounted on the vial assembly 200 and is in communication with the vial assembly 200.

[0084] Proximal end a and distal end b refer to the approximate orientation of the injection device along the Y-axis. Proximal end a refers to the end of the injection device that is furthest from the injection site during injection, and distal end b refers to the end of the injection device that is closest to the injection site during injection. Understandably, the vial assembly 200, the injection needle 300, and the syringe drive mechanism 100 all possess the aforementioned proximal end a and distal end b, and each component of the syringe drive mechanism 100 also correspondingly possesses the aforementioned proximal end a and distal end b.

[0085] Specifically, the vial assembly 200 is mounted at the distal end b of the syringe drive mechanism 100, and the injection needle 300 is mounted at the distal end b of the vial assembly 200. When the injection device is in use, the injection needle 300 is inserted into the injection site, and the components in the syringe drive mechanism 100 move towards the distal end b to drive the medication within the vial assembly 200. The injection site can be a part of the human or animal body, such as the arm, buttocks, or waist.

[0086] Although the syringe drive mechanism 100 and injection device provided in this application embodiment are designed based on the problems encountered in the application of insulin injection pens, they are not limited thereto. The syringe drive mechanism 100 and injection device can be applied to the injection of drugs such as insulin and antibody drugs.

[0087] Please refer to the following: Figures 3 to 13 And in conjunction with other accompanying figures. Figure 3 for Figure 1 decomposition Figure 2 , Figure 4 for Figure 1 A partial sectional view along AA, Figure 5 This is a perspective structural view of the housing 11 of the syringe drive mechanism 100 provided in some embodiments of this application. Figure 6 for Figure 5 sectional view, Figure 7 This is a partial structural diagram of the syringe drive mechanism 100 provided in some embodiments of this application. Figure 8 This is a perspective view of the numerical rotating cylinder 40 of the syringe drive mechanism 100 provided in some embodiments of this application. Figure 9 This is a perspective structural view of the adjustment component 30 of the syringe drive mechanism 100 provided in some embodiments of this application. Figure 10 Three-dimensional structure of the first adjusting member 311 of the syringe drive mechanism 100 provided in some embodiments of this application Figure 1 , Figure 11 This is a perspective structural view of the memory element 70 of the syringe drive mechanism 100 provided in some embodiments of this application. Figure 12 This is a perspective structural view of the push rod assembly 60 of the syringe drive mechanism 100 provided in some embodiments of this application. Figure 13 for Figure 12 Enlarged view of point B in the middle. Figure 1 and Figure 4 In this embodiment, the vial assembly 200 is mounted on the syringe drive mechanism 100. The syringe drive mechanism 100 provided in this application includes a housing assembly 10, a clutch assembly 20, an adjustment assembly 30, a numerical rotating cylinder 40, a reset member 50, a push rod assembly 60, and a memory member 70.

[0088] The housing assembly 10 is used to connect to the vial assembly 200, specifically, the vial assembly 200 is mounted at the distal end b of the housing assembly 10.

[0089] The housing assembly 10 is provided with a first limiting part 111 and a second limiting part 141. The first limiting part 111 is used to limit the clutch assembly 20 in the circumferential direction W to restrict the rotation of the clutch assembly 20 relative to the housing assembly 10. The second limiting part 141 is used to limit the rotation stroke of the numerical rotating cylinder 40 in the counterclockwise direction W2 relative to the housing assembly 10.

[0090] The clutch assembly 20 is disposed within the housing assembly 10 and engages with the first limiting portion 111 in a circumferential W direction. The clutch assembly 20 is configured to disengage from the first limiting portion 111 under the action of a first external force. Understandably, in the initial state, the clutch assembly 20 is circumferentially limited to the first limiting portion 111, thereby limiting the clutch assembly 20 and the housing assembly 10 in the circumferential W direction and restricting rotation of the clutch assembly 20 relative to the housing assembly 10, preventing the clutch assembly 20 from rotating relative to the housing assembly 10. When the clutch assembly 20 is subjected to the first external force, the clutch assembly 20 can disengage from the first limiting portion 111, thereby releasing the circumferential W limitation between the clutch assembly 20 and the housing assembly 10, at which point the clutch assembly 20 can rotate relative to the housing assembly 10.

[0091] The adjusting component 30 is rotatably disposed within the housing assembly 10. The adjusting component 30 is limited to the clutch assembly 20 in a counterclockwise direction W2, and is further configured to rotate relative to the clutch assembly 20 under the action of a second external force. Understandably, in the initial state of the injection device, the adjusting component 30 is limited to the clutch assembly 20 in a counterclockwise direction, i.e., the clutch assembly 20 limits the rotation of the adjusting component 30 in the counterclockwise direction W2, preventing the adjusting component 30 from rotating relative to the clutch assembly 20 in the counterclockwise direction W2. When the clutch assembly 20 disengages from the first limiting part 111, and the adjusting component 30 rotates relative to the housing assembly 10 in the counterclockwise direction W2, the clutch assembly 20 can rotate along with the adjusting component 30 in the counterclockwise direction W2 relative to the housing assembly 10. When the adjusting component 30 is subjected to the second external force, the adjusting component 30 can rotate relative to both the clutch assembly 20 and the housing assembly 10. Specifically, when the adjustment component 30 is subjected to a second external force, the adjustment component 30 can rotate relative to the clutch component 20 and the housing component 10 in the clockwise direction W1, or it can rotate relative to the clutch component 20 and the housing component 10 in the counterclockwise direction W2.

[0092] The numerical rotating cylinder 40 is rotatably threaded into the housing assembly 10. The numerical rotating cylinder 40 is sleeved around the adjusting assembly 30 and is circumferentially limited to the adjusting assembly 30. The numerical rotating cylinder 40 is also configured to move axially relative to the housing assembly 10 and the adjusting assembly 30 relative to the adjusting assembly 30 as the adjusting assembly 30 rotates, thereby adjusting the scale. Understandably, when the adjusting assembly 30 rotates relative to the housing assembly 10, the numerical rotating cylinder 40 rotates with the adjusting assembly 30 relative to the housing assembly 10 under the circumferential W-limiting action of the adjusting assembly 30, and the numerical rotating cylinder 40 also moves axially relative to the housing assembly 10 and the adjusting assembly 30 under the limiting action of the housing assembly 10 and the adjusting assembly 30, thereby adjusting the position of the numerical rotating cylinder 40 in the axial Y direction to achieve scale adjustment. Specifically, when the adjusting assembly 30 rotates relative to the housing assembly 10 in the counterclockwise direction W2 or in the clockwise direction W1, the numerical rotating cylinder 40 can move axially relative to the housing assembly 10 and the adjusting assembly 30. As an example, when the adjustment component 30 rotates clockwise W1 relative to the housing component 10, the numerical rotating cylinder 40 rotates clockwise W1 with the adjustment component 30 and moves axially Y toward the distal end b relative to the housing component 10 and the adjustment component 30; when the adjustment component 30 rotates counterclockwise W2 relative to the housing component 10, the numerical rotating cylinder 40 rotates counterclockwise W2 with the adjustment component 30 and moves axially Y toward the proximal end a relative to the housing component 10 and the adjustment component 30.

[0093] A reset member 50 is connected between the housing assembly 10 and the adjustment assembly 30. The reset member 50 is configured to provide a driving force to the adjustment assembly 30 to rotate counterclockwise in the direction W2, so that the numerical cylinder 40 is limited to the second limiting portion 141 in the counterclockwise direction W2. Understandably, in the initial state, the injection device has the numerical cylinder 40 limited to the second limiting portion 141 in the counterclockwise direction W2. When the numerical cylinder 40 is not limited to the second limiting portion 141 in the counterclockwise direction W2, and the clutch assembly 20 disengages from the first limiting portion 111, the reset member 50 can drive the adjustment assembly 30 to rotate counterclockwise in the direction W2, so that the numerical cylinder 40 rotates counterclockwise in the direction W2 to the second limiting portion 141. When the numerical cylinder 40 is limited to the second limiting portion 141 in the counterclockwise direction W2, the adjustment assembly 30 cannot continue to rotate counterclockwise in the direction W2. The reset member 50 can be a torsion spring, spring, or spring-loaded component with elastic force.

[0094] The push rod assembly 60 is threadedly connected to the housing assembly 10 such that when the push rod assembly 60 rotates relative to the housing assembly 10, the push rod assembly 60 moves axially Y relative to the housing assembly 10. The push rod assembly 60 is circumferentially W-limited on the clutch assembly 20 such that when the clutch assembly 20 rotates, the push rod assembly 60 can rotate with the clutch assembly 20. The push rod assembly 60 is also configured to move distally b relative to the housing assembly 10 and the clutch assembly 20 when rotating counterclockwise W2 to drive the medicine within the vial assembly 200. Understandably, when the clutch assembly 20 rotates counterclockwise W2 relative to the housing assembly 10, the push rod assembly 60 rotates counterclockwise W2 with the clutch assembly 20 relative to the housing assembly 10, such that the push rod assembly 60 moves axially Y-directed distally b relative to the housing assembly 10 and the clutch assembly 20 to extend axially Y-directed distally b outside the housing assembly 10 and drive the medicine within the vial assembly 200. It should be further explained that, based on the threaded connection of the push rod assembly 60 to the housing assembly 10, the push rod assembly 60 can also rotate clockwise W1 relative to the housing assembly 10. When the push rod assembly 60 rotates clockwise W1 relative to the housing assembly 10, the push rod assembly 60 can move axially Y towards the proximal end a relative to the housing assembly 10. As an example, at least a portion of the push rod assembly 60 is disposed within the housing assembly 10, i.e., the housing assembly 10 is sleeved outside the push rod assembly 60. The adjusting assembly 30 can be spaced outside the push rod assembly 60, such that the adjusting assembly 30 can rotate relative to the push rod assembly 60, and the push rod assembly 60 can also move axially Y relative to the adjusting assembly 30. The clutch assembly 20 can be sleeved outside the push rod assembly 60 and is circumferentially limited in engagement with the push rod assembly 60.

[0095] The memory element 70 is threadedly connected to the push rod assembly 60, such that when the memory element 70 rotates relative to the push rod assembly 60, it can move axially Y relative to both the push rod assembly 60 and the adjusting assembly 30. The memory element 70 is circumferentially W-limited within the adjusting assembly 30, such that when the adjusting assembly 30 rotates relative to the housing assembly 10, the memory element 70 rotates with the adjusting assembly 30. As an example, the memory element 70 is sleeved on the push rod assembly 60 and threadedly connected to it. The adjusting assembly 30 is sleeved on the memory element 70 and circumferentially W-limited in engagement with it. The clutch assembly 20 is sleeved on the push rod assembly 60 and circumferentially W-limited in engagement with it.

[0096] The memory element 70 is configured to move along the axial direction Y relative to the adjusting assembly 30 and the pushing rod assembly 60 when rotating relative to the pushing rod assembly 60. The pushing rod assembly 60 is provided with a third limiting portion 61, which limits the rotational stroke of the memory element 70 in the clockwise direction W1. Understandably, when the adjusting assembly 30 rotates relative to the housing assembly 10 and the clutch assembly 20 under the action of a second external force, the memory element 70 rotates with the adjusting assembly 30 relative to the pushing rod assembly 60 and moves along the axial direction Y relative to the pushing rod assembly 60 and the adjusting assembly 30. When the adjusting component 30 rotates clockwise in the direction W1 relative to the housing assembly 10 and the clutch assembly 20 under the action of the second external force, the memory element 70 rotates clockwise in the direction W1 relative to the push rod assembly 60 along with the adjusting component 30. It can rotate until it is limited to the third limiting part 61 of the push rod assembly 60, so that the memory element 70 can no longer rotate clockwise in the direction W1 relative to the push rod assembly 60. Then the adjusting component 30 can no longer rotate clockwise in the direction W1 relative to the clutch assembly 20 and the housing assembly 10. That is, the third limiting part 61 is used to position the rotational stroke of the adjusting component 30 relative to the clutch assembly 20 and the housing assembly 10 in the clockwise direction W1.

[0097] It should be noted that when the adjusting component 30 rotates clockwise W1 relative to the housing assembly 10 and the clutch assembly 20 by a predetermined angle under the action of the second external force, the numerical rotating cylinder 40 rotates clockwise W1 relative to the housing assembly 10 along with the adjusting component 30, and moves a predetermined numerical stroke relative to the housing assembly 10 and the adjusting component 30 along the axial direction Y, thereby displaying a predetermined scale. The memory element 70 also rotates clockwise W1 relative to the push rod assembly 60 by the predetermined angle along with the adjusting component 30, and moves a predetermined memory stroke relative to the push rod assembly 60 and the adjusting component 30 along the axial direction Y. When the clutch assembly 20 disengages from the first limiting part 111 under the action of the first external force, the adjusting component 30 rotates counterclockwise W2 relative to the housing assembly 10 by the aforementioned predetermined angle under the driving action of the reset member 50. The numerical rotating cylinder 40 rotates counterclockwise (W2) relative to the housing assembly 10 by a predetermined angle along with the adjusting component 30, and moves along the axial direction (Y) relative to the housing assembly 10 and the adjusting component 30 by a predetermined numerical stroke, so that the position of the numerical rotating cylinder 40 returns to its initial state. This can be considered as the scale displayed on the numerical rotating cylinder 40 returning to 0, i.e., returning to the initial state. Along with the adjusting component 30, the clutch component 20 and the push rod assembly 60 rotate counterclockwise (W2) relative to the housing assembly 10 by the predetermined angle, and the push rod assembly 60 moves along the axial direction (Y) towards the distal end (b) relative to the housing assembly 10 by a predetermined injection stroke. Therefore, the predetermined angle, predetermined scale, predetermined numerical stroke, predetermined memory stroke, and predetermined injection stroke are correspondingly set, so that the scale displayed on the numerical rotating cylinder 40 can be used to represent a single injection stroke of the push rod assembly 60. When the memory element 70 is positioned clockwise W1 on the third limiting part 61, and the numerical rotating cylinder 40 is positioned counterclockwise W2 on the third limiting part 61, the cumulative memory stroke of the memory element 70 relative to the push rod assembly 60 along the axial Y is at its maximum, and the cumulative injection stroke of the push rod assembly 60 relative to the housing assembly 10 along the axial Y towards the distal end b is also at its maximum. Furthermore, the scale displayed on the numerical rotating cylinder 40 returns to 0, indicating that the medicine in the vial assembly 200 has been completely injected. Therefore, the maximum cumulative memory stroke of the memory element 70 relative to the push rod assembly 60 along the axial Y is correspondingly set to the maximum cumulative injection stroke of the push rod assembly 60 relative to the housing assembly 10 along the axial Y towards the distal end b. In the initial state of the injection device, the distance between the memory element 70 and the third limiting part 61 along the axial Y can be used to represent the maximum cumulative memory stroke of the memory element 70 relative to the push rod assembly 60 along the axial Y, thus corresponding to the axial Y height of the medicine in the vial assembly 200.

[0098] Based on the above structure, the working principle of the injection device is as follows:

[0099] In the initial state, the clutch assembly 20 is circumferentially limited to the first limiting part 111 along the W direction, the adjusting assembly 30 is limited to the clutch assembly 20 in the counterclockwise direction W2, and the numerical rotating cylinder 40 is limited to the second limiting part 141 in the counterclockwise direction W2, so that the scale displayed by the numerical rotating cylinder 40 is 0. The memory element 70 and the third limiting part 61 are spaced apart along the axial direction Y, and the distance between the memory element 70 and the third limiting part 61 in the axial direction Y is set by the axial Y height of the medicine in the vial assembly 200.

[0100] When the injection device is in use, the second external force first drives the adjustment component 30 to rotate clockwise W1 relative to the housing component 10 and the clutch component 20. Based on the circumferential W-direction limiting fit between the adjustment component 30 and the numerical rotating cylinder 40, and between the memory element 70 and the adjustment component 30, the numerical rotating cylinder 40 and the memory element 70 rotate clockwise W1 relative to the housing component 10 and the clutch component 20 with the adjustment component 30. This causes the memory element 70 to move toward the third limiting part 61 relative to the push rod component 60 and the adjustment component 30, and the numerical rotating cylinder 40 moves axially Y relative to the housing component 10 and the adjustment component 30 to display the scale, thereby realizing the scale adjustment of the injection device. Since the clutch assembly 20 is circumferentially limited on the first limiting part 111, and the adjusting assembly 30 is limited on the clutch assembly 20 in the counterclockwise direction W2, the adjusting assembly 30 cannot rotate relative to the housing assembly 10 in the counterclockwise direction W2 under the driving force of the reset member 50 after the second external force is removed and no first external force is applied.

[0101] Then, the clutch assembly 20 is driven to disengage from the first limiting part 111 by the first external force. The adjusting assembly 30 rotates counterclockwise W2 relative to the housing assembly 10 under the driving force of the reset member 50. Since the adjusting assembly 30 is limited to the clutch assembly 20 in the counterclockwise direction W2, and the clutch assembly 20 and the push rod assembly 60 are limited in the circumferential direction W, the numerical rotating cylinder 40, the memory element 70 and the clutch assembly 20 all rotate counterclockwise W2 relative to the housing assembly 10 with the adjusting assembly 30, and the push rod assembly 60 rotates counterclockwise W2 relative to the housing assembly 10 with the clutch assembly 20. That is, under the driving force of the reset member 50, the adjusting assembly 30, the numerical rotating cylinder 40, the memory element 70, the clutch assembly 20 and the push rod assembly 60 rotate together in the counterclockwise direction W2 relative to the housing assembly 10. During this process, the push rod assembly 60 moves axially Y toward the distal end b relative to the housing assembly 10, the adjusting assembly 30, and the clutch assembly 20 to drive the medicine in the vial assembly 200. Under the driving force of the reset member 50, when the numerical rotating cylinder 40 rotates counterclockwise W2 relative to the housing assembly 10 with the adjusting assembly 30 and is limited to the second limiting part 141, the numerical rotating cylinder 40 stops rotating counterclockwise W2 relative to the housing assembly 10, so that the adjusting assembly 30, the clutch assembly 20, the numerical rotating cylinder 40, the memory unit 70, and the push rod assembly 60 all stop rotating counterclockwise W2, thereby completing a single injection of the medicine.

[0102] It should be further explained that during the scale adjustment of the injection device, the adjusting component 30 can be rotated clockwise (W1) relative to the housing assembly 10 and the clutch assembly 20 by a second external force, or it can be rotated counterclockwise (W2) relative to the housing assembly 10 and the clutch assembly 20 by a second external force. This helps to improve the positional accuracy of the numerical cylinder 40 in the axial Y direction, thereby improving the accuracy of the scale displayed by the numerical cylinder 40. Specifically, during the scale adjustment of the injection device, since the numerical cylinder 40 is limited to the second limiting part 141 in the counterclockwise (W2) direction, it is necessary to first use the second external force to drive the adjusting component 30 to rotate clockwise (W1), and then drive the adjusting component 30 to rotate counterclockwise (W2) to achieve accurate adjustment of the position of the numerical cylinder 40.

[0103] It should be noted that the liquid in the vial assembly 200 can be used for a single injection or for multiple injections.

[0104] When the medicine in the vial assembly 200 is used for a single injection, during the scale adjustment of the injection device, the adjustment assembly 30 can be driven by a second external force to rotate clockwise W1 relative to the housing assembly 10 and the clutch assembly 20 until the memory element 70 is limited to the third limiting part 61 of the push rod assembly 60 in the clockwise direction W1. At this time, the scale displayed on the numerical rotary cylinder 40 is at its maximum. Thus, during the injection of the medicine, when the clutch assembly 20 is driven to disengage from the first limiting part 111 by the first external force, under the drive of the reset member 50, the adjusting assembly 30, the numerical rotating cylinder 40, the memory unit 70, the clutch assembly 20 and the push rod assembly 60 rotate together in the counterclockwise direction W2 relative to the housing assembly 10 until the numerical rotating cylinder 40 is limited to the second limiting part 141 in the counterclockwise direction W2. At this time, the push rod assembly 60 moves to the maximum distance b in the axial direction Y relative to the housing assembly 10, and it can be considered that the medicine in the vial assembly 200 has been injected. In this way, the effect of injecting the medicine in the vial assembly 200 in one go can be achieved.

[0105] When the liquid in the vial assembly 200 is used for multiple injections, the injection needle 300 is detachably installed inside the vial assembly 200. To determine the required dosage, a second external force is applied to drive the adjusting assembly 30 to rotate clockwise (W1) relative to the housing assembly 10 and the clutch assembly 20 by a predetermined angle. This causes the memory element 70 to move along the axial direction (Y) towards the third limiting part 61 relative to the housing assembly 10 and the adjusting assembly 30 by a predetermined memory stroke. Simultaneously, the numerical rotating cylinder 40 moves along the axial direction (Y) relative to the housing assembly 10 and the adjusting assembly 30 by a predetermined numerical stroke to display a predetermined scale, thus achieving scale adjustment. Then, a first external force is applied to drive the clutch assembly 20 to disengage from the first limiting part 111. Under the drive of the reset element 50, the numerical rotating cylinder 40 moves along the axial direction (Y) relative to the housing assembly 10 and the adjusting assembly 30 to reset the scale to 0. The push rod assembly 60 moves along the axial direction (Y) towards the distal end (b) relative to the housing assembly 10 by a predetermined injection stroke, thus injecting the predetermined dosage of liquid into the vial assembly 200. Then, the injection needle 300 is replaced, and the required dosage of medicine is injected again. A second external force is used to drive the adjusting component 30 to rotate clockwise W1 relative to the housing assembly 10 and the clutch assembly 20 by a predetermined angle. Then, a first external force is used to drive the clutch assembly 20 to disengage from the first limiting part 111, so that the predetermined dosage of medicine can be injected again... This process continues until, during scale adjustment, when a second external force drives the adjusting component 30 to rotate clockwise W1 relative to the housing assembly 10 and the clutch assembly 20, the memory element 70 is limited clockwise W1 to the third limiting part 61 of the push rod assembly 60. After this injection is completed, the medicine in the vial assembly 200 can be considered completely injected. In this way, multiple injections of medicine in the vial assembly 200 can be achieved.

[0106] The syringe driving mechanism 100 provided in this application embodiment has a third limiting part 61 on the push rod assembly 60. The third limiting part 61 is used to limit the rotation stroke of the memory element 70 in the clockwise direction W1. When the scale adjustment is completed, the memory element 70 is limited to the third limiting part 61 of the push rod assembly 60 in the clockwise direction W1, and the adjusting component 30 can no longer rotate in the clockwise direction W1 relative to the clutch component 20, so that the scale adjustment can no longer be performed. After the injection work is completed, the numerical cylinder 40 rotates in the counterclockwise direction W2 to be limited to the second limiting part 141, so that the adjusting component 30 can no longer rotate in the counterclockwise direction W2. Then the push rod assembly 60 can no longer move to the distal end b to realize the injection work. The stroke of the push rod assembly 60 moving to the distal end b has been used up, and it can be considered that the medicine in the vial assembly 200 has been injected. Therefore, after the medicine in the vial assembly 200 is used up, the adjustment component 30 locks itself, preventing further scale adjustments and injections, thus reducing the risk of accidental injection after the medicine in the vial assembly 200 is used up.

[0107] It should be noted that the first external force and the second external force are different.

[0108] The circumferential direction W refers to the circumferential direction, which is perpendicular to the axial direction Y. The circumferential direction W can include clockwise direction W1 and counterclockwise direction W2, with clockwise and counterclockwise directions W1 and W2 being opposite. The clockwise and counterclockwise directions W1 and W2 can be defined from a perspective pointing from the proximal end a to the distal end b, or from a perspective pointing from the distal end b to the proximal end a. As an example, ... Figures 3 to 13 As shown, clockwise direction W1 and counterclockwise direction W2 are defined from the perspective of the near end a pointing to the far end b.

[0109] In some embodiments, please refer to the following: Figures 1 to 3 , Figure 8 And in conjunction with other accompanying drawings. The numerical rotating cylinder 40 is provided with a scale, and the housing assembly 10 is provided with a window 101, which is used to display the scale on the numerical rotating cylinder 40. In the operation of scale adjustment of the injection device, by adjusting the position of the numerical rotating cylinder 40 in the axial Y direction, different scales on the numerical rotating cylinder 40 can be aligned with the window 101, so that the window 101 displays different scales.

[0110] In some embodiments, please refer to the following: Figures 6 to 9 And in conjunction with other accompanying drawings. The numerical rotating cylinder 40 is threadedly connected to the housing assembly 10 so that when the numerical rotating cylinder 40 rotates with the adjusting assembly 30, the numerical rotating cylinder 40 can move relative to the housing assembly 10 and the adjusting assembly 30 along the axial direction Y.

[0111] Specifically, the outer peripheral wall of the numerical rotating cylinder 40 is provided with a second threaded groove 401, and the inner peripheral wall of the housing assembly 10 is provided with a second thread 112. The second threaded groove 401 and the second thread 112 are threadedly engaged so that the numerical rotating cylinder 40 can move along the axial direction Y when it rotates relative to the housing assembly 10.

[0112] In some embodiments, please refer to the following: Figures 6 to 9 In conjunction with other accompanying drawings, the outer peripheral wall of the adjusting component 30 is provided with a first rib 3122, and the inner peripheral wall of the numerical rotating cylinder 40 is provided with a first limiting groove 402. The first rib 3122 is limited in the first limiting groove 402 along the circumferential direction W, and the first rib 3122 can move along the axial direction Y within the first limiting groove 402, so that when the numerical rotating cylinder 40 rotates with the adjusting component 30 relative to the housing component 10, the numerical rotating cylinder 40 can move along the axial direction Y relative to the housing component 10 and the adjusting component 30.

[0113] In some embodiments, please refer to the following: Figure 10 and Figure 11 And in conjunction with other accompanying drawings. The outer peripheral wall of the memory element 70 is provided with a second rib 72, and the inner peripheral wall of the adjusting assembly 30 is provided with a second limiting groove 304. The second rib 72 is circumferentially limited within the second limiting groove 304 and can move axially Y within the second limiting groove 304. Thus, when the adjusting assembly 30 rotates relative to the housing assembly 10 under the action of a second external force, the memory element 70 rotates with the adjusting assembly 30 and moves axially Y relative to the adjusting assembly 30 and the push rod assembly 60. When the adjusting assembly 30 disengages from the first limiting part 111 under the action of a first external force, under the driving force of the reset member 50, the adjusting assembly 30, the clutch assembly 20, the memory element 70, the push rod assembly 60, and the numerical rotating cylinder 40 rotate together counterclockwise W2 relative to the housing assembly 10. The push rod assembly 60 moves axially Y toward the distal end b relative to the housing assembly 10, and the memory element 70 moves with the push rod assembly 60 relative to the housing assembly 10 and the adjusting assembly 30.

[0114] In some embodiments, please refer to the following: Figure 3 and Figure 4In conjunction with other accompanying drawings, the memory element 70 is located at the proximal end a of the clutch assembly 20 along the axial direction Y, and the third limiting part 61 is located at the proximal end a of the memory element 70. Thus, when the adjusting assembly 30 rotates clockwise W1 relative to the housing assembly 10 under the action of a second external force, the memory element 70 rotates clockwise W1 with the adjusting assembly 30 and moves along the axial direction Y towards the proximal end a relative to the push rod assembly 60 and the adjusting assembly 30. When the adjusting assembly 30 rotates counterclockwise W2 relative to the housing assembly 10 under the action of a second external force, the memory element 70 moves along the axial direction Y towards the distal end b relative to the push rod assembly 60 and the adjusting assembly 30. Thus, during the injection of the medicine, when the push rod assembly 60 moves along the axial direction Y towards the distal end b relative to the housing assembly 10, the problem of the memory element 70 being blocked by the clutch assembly 20 while moving along the axial direction Y of the push rod assembly 60, causing interference to the axial movement Y of the push rod assembly 60, can be solved.

[0115] In some embodiments, please refer to the following: Figure 3 , Figure 4 and Figure 7 Furthermore, in conjunction with other accompanying drawings, a second limiting portion 141 is provided at the proximal end a of the numerical rotating cylinder 40 along the Y-axis.

[0116] Thus, when the adjusting component 30 rotates clockwise W1 relative to the housing assembly 10, the numerical rotating cylinder 40 rotates clockwise W1 with the adjusting component 30 and moves axially Y toward the distal end b relative to the housing assembly 10 and the adjusting component 30. When the adjusting component 30 rotates counterclockwise relative to the housing assembly 10, the numerical rotating cylinder 40 rotates counterclockwise W2 with the adjusting component 30 and moves axially Y toward the proximal end a relative to the housing assembly 10 and the adjusting component 30.

[0117] In some embodiments, please refer to the following: Figures 1 to 7 And in conjunction with other accompanying drawings. The syringe drive mechanism 100 also includes a knob 80, which is rotatably mounted on the housing assembly 10 and engages with the adjustment assembly 30 in a circumferential W-direction limiting manner. Thus, the second external force acts as a rotational operation on the knob 80. Specifically, when the knob 80 is rotated, the adjustment assembly 30 can rotate relative to the housing assembly 10 and the clutch assembly 20 under the drive of the knob 80.

[0118] In some embodiments, please refer to Figure 14 And in conjunction with other accompanying figures. Figure 14 This is a perspective view of the clutch component 22 of the syringe drive mechanism 100 provided in some embodiments of this application. The clutch component 20 has a plurality of ratchet teeth 221 arranged circumferentially W at one end along the axial direction Y towards the proximal end a, and each ratchet tooth 221 is inclined in the clockwise direction W1.

[0119] Understandably, in the axial direction Y, the adjustment component 30 is located at the proximal end a of the clutch component 20.

[0120] In some embodiments, please refer to the following: Figure 9 , Figure 14 and Figure 15 And in conjunction with other accompanying figures. Figure 15 This is a structural diagram of the second adjusting member 312 and the elastic tooth 32 of the syringe drive mechanism 100 provided in some embodiments of this application. The adjusting assembly 30 includes an adjusting body 31 and an elastic tooth 32. The adjusting body 31 is rotatably disposed within the housing assembly 10 and is located at one end of the clutch assembly 20 along the axial direction Y towards the proximal end a. The numerical rotating cylinder 40 is sleeved outside the adjusting body 31 and is circumferentially limited to the adjusting body 31. The adjusting body 31 is connected to the reset member 50 and is circumferentially limited to the memory member 70. The elastic tooth 32 is disposed on the adjusting body 31 and extends out of the adjusting body 31 along the axial direction Y towards the distal end b. The elastic tooth 32 elastically engages between two adjacent ratchet teeth 221 and is limited to the ratchet teeth 221 in a counterclockwise direction W2. The elastic tooth 32 is configured to elastically move relative to the ratchet teeth 221 in a clockwise direction W1 under the action of a second external force.

[0121] Understandably, in the initial state, the elastic tooth 32 engages between two adjacent ratchet teeth 221 and is limited to the ratchet teeth 221 in the counterclockwise direction W2. Thus, when the adjusting component 30 is not subjected to a second external force, the elastic tooth 32 is limited to the ratchet teeth 221 in the counterclockwise direction W2, thereby preventing the adjusting component 30 from rotating relative to the clutch component 20 in the counterclockwise direction W2.

[0122] Understandably, when the adjusting component 30 rotates clockwise W1 relative to the housing component 10 under the action of the second external force, the adjusting body 31 rotates clockwise W1 relative to the housing component 10, and the elastic tooth 32 moves clockwise W1 under the drive of the adjusting body 31 and elastically deforms relative to the ratchet tooth 221, thereby causing the elastic tooth 32 to move elastically relative to the ratchet tooth 221 in the clockwise W1 direction, that is, causing the adjusting component 30 to rotate clockwise W1 relative to the clutch component 20.

[0123] In this way, the adjusting component 30 can rotate clockwise W1 relative to the clutch component 20 under the action of the second external force, thereby realizing the scale adjustment work.

[0124] In some embodiments, please refer to the following: Figure 9 , Figure 10 , Figure 15 and Figure 16 And in conjunction with other accompanying figures. Figure 16Three-dimensional structure of the first adjusting member 311 of the syringe drive mechanism 100 provided in some embodiments of this application Figure 2 The adjusting body 31 includes a first adjusting member 311 and a second adjusting member 312. The first adjusting member 311 is circumferentially limited to the memory member 70 along the W direction. The second adjusting member 312 is sleeved on the first adjusting member 311. An elastic tooth 32 is provided on the second adjusting member 312, which is connected to the reset member 50. The numerical rotating cylinder 40 is sleeved on the second adjusting member 312 and is circumferentially limited to the second adjusting member 312 along the W direction. One of the first adjusting member 311 and the second adjusting member 312 has a latch 3121, and the other has a groove 301. The latch 3121 is limited within the groove 301 along the W direction and the Y direction, and the size of the groove 301 is larger than the size of the latch 3121 in the W direction. The first adjusting member 311 is configured such that when it rotates counterclockwise relative to the second adjusting member 312 in the W direction under the action of a second external force, it drives the elastic tooth 32 to move elastically away from the ratchet tooth 221.

[0125] In some possible designs, such as Figure 15 and Figure 16 As shown, the first adjusting member 311 is provided with the aforementioned slot 301, and the second adjusting member 312 is provided with the aforementioned buckle 3121. In some other possible designs, the first adjusting member 311 is provided with the aforementioned buckle 3121, and the second adjusting member 312 is provided with the aforementioned slot 301.

[0126] The buckle 3121 is engaged in the slot 301 so that the first adjusting member 311 and the second adjusting member 312 can achieve circumferential W-direction and axial Y-direction.

[0127] Understandably, the slot 301 has inner walls at both ends along the circumferential direction W, so that the latch 3121 is limited along the circumferential direction W between the inner walls at both ends of the slot 301, thereby achieving circumferential W-level positioning of the latch 3121 and the slot 301. When the second adjusting member 312 rotates relative to the housing assembly 10, the latch 3121 can rotate between the inner walls at both ends of the slot 301 along the circumferential direction W until the latch 3121 abuts against the inner wall at either end of the slot 301 along the circumferential direction W.

[0128] For ease of description, the inner walls at both ends of the slot 301 along the circumferential direction W are defined as the first inner wall (not shown in the figure) and the second inner wall (not shown in the figure).

[0129] With this configuration, when the first adjusting member 311 rotates clockwise W1 relative to the housing assembly 10 under the action of a second external force, the latch 3121 abuts against the first inner wall of the slot 301 along the circumferential W direction, causing the first adjusting member 311 to drive the second adjusting member 312 to rotate clockwise W1. The memory unit 70 rotates clockwise W1 with the first adjusting member 311 and moves axially Y relative to the push rod assembly 60 and the adjusting assembly 30. The numerical rotating cylinder 40 rotates clockwise W1 with the second adjusting member 312 and moves axially Y relative to the housing assembly 10 and the adjusting assembly 30.

[0130] When the first adjusting member 311 rotates counterclockwise W2 relative to the housing assembly 10 under the action of the second external force, the first adjusting member 311 will first rotate counterclockwise W2 relative to the second adjusting member 312 by a certain angle. Specifically, the latch 3121 rotates circumferentially W within the slot 301 by a certain angle until the latch 3121 abuts against the second inner wall of the slot 301 circumferentially W. When the latch 3121 rotates circumferentially W within the slot 301, the first adjusting member 311 will rotate counterclockwise W2 relative to the second adjusting member 312, driving the elastic tooth 32 to move elastically away from the ratchet tooth 221. This reduces the engagement depth between the elastic tooth 32 and the ratchet tooth 221, causing the elastic tooth 32 to disengage from the ratchet tooth 221 or be in a semi-engaged state with the ratchet tooth 221. This facilitates the elastic movement of the elastic tooth 32 relative to the ratchet tooth 221. After the buckle 3121 rotates a certain angle in the slot 301 along the circumferential direction W, it abuts against the second inner wall of the slot 301 along the circumferential direction W, so that when the first adjusting member 311 continues to rotate under the action of the second external force, it can drive the second adjusting member 312 to rotate in the counterclockwise direction W2. The elastic tooth 32 on the second adjusting member 312 can move elastically relative to the ratchet tooth 221 in the counterclockwise direction W2, thereby making the adjusting assembly 30 rotate relative to the housing assembly 10 and the clutch assembly 20 in the counterclockwise direction W2.

[0131] Therefore, under the action of the second external force, the adjusting component 30 can rotate clockwise W1 relative to the housing assembly 10 and the clutch assembly 20, and also counterclockwise W2 relative to the housing assembly 10 and the clutch assembly 20, thereby realizing the movement of the numerical rotating cylinder 40 and the memory element 70 in the axial Y direction to achieve scale adjustment. This prevents the instantaneous release of stored force due to the force stored in the reset element 50, which would prevent it from reverting. This helps improve the accuracy of scale adjustment of the injection device.

[0132] It should be further explained that the elastic tooth 32 has elastic properties. When the second external force is removed, due to the action of the reset member 50, the second adjusting member 312 can rotate counterclockwise W2 relative to the housing assembly 10 under the elastic action of the reset member 50. The second adjusting member 312 can rotate a certain angle counterclockwise W2 relative to the first adjusting member 311. Specifically, the latch 3121 rotates a certain angle circumferentially W within the slot 301 until the latch 3121 abuts against the first inner wall of the slot 301 circumferentially W. This allows the elastic tooth 32 to reset and fully engage between the two adjacent ratchet teeth 221.

[0133] In some embodiments, the reset member 50 is an elastic structure. When the second external force is removed, the second adjusting member 312 can rotate relative to the housing assembly 10 in the counterclockwise direction W2 under the elastic action of the reset member 50. The second adjusting member 312 can also rotate relative to the first adjusting member 311 in the counterclockwise direction W2 by a certain angle. Specifically, the latch 3121 rotates a certain angle in the circumferential direction W within the slot 301 until the latch 3121 abuts against the first inner wall of the slot 301 in the circumferential direction W. Thus, when the first adjusting member 311 rotates relative to the housing assembly 10 in the clockwise direction W1, the latch 3121 abuts against the first inner wall, allowing the first adjusting member 311 to drive the second adjusting member 312 to rotate together in the clockwise direction W1, thereby accurately achieving scale adjustment. When the adjusting component 30 is subjected to the first external force, under the elastic action of the reset component 50, the second adjusting component 312 can drive the first adjusting component 311 to rotate in the counterclockwise direction W2 together, so as to accurately realize the injection of medicine.

[0134] Specifically, such as Figure 10 and Figure 15 The second adjusting member 312 has the aforementioned first rib 3122 on its outer peripheral wall, and the first adjusting member 311 has a second limiting groove 304 on its inner peripheral wall.

[0135] In some embodiments, based on the fact that the size of the slot 301 is larger than the size of the buckle 3121 in the circumferential direction W, the rotation angle of the first adjusting member 311 relative to the second adjusting member 312 can be less than 15°.

[0136] In some embodiments, please refer to the following: Figure 9 , Figure 10 , Figures 15 to 17 And in conjunction with other accompanying figures. Figure 17 for Figure 16Enlarged view at point C. The first adjusting member 311 includes a first adjusting part 3111 and a second adjusting part 3112. The first adjusting part 3111 is circumferentially limited to the memory member 70 along the W direction, and the second adjusting member 312 is sleeved outside the first adjusting part 3111. One of the first adjusting part 3111 and the second adjusting member 312 is provided with a buckle 3121, and the other is provided with a groove 301. The second adjusting part 3112 is located at the distal end b of the first adjusting part 3111 along the Y direction. The second adjusting part 3112 is provided with a relief groove 302 through the second adjusting part 3112 along the Y direction, and the elastic tooth 32 extends out of the relief groove 302 along the Y direction to the distal end b. The groove wall of the relief groove 302 is provided with a guide surface 303. The guide surface 303 is configured such that when the first adjusting part 3111 rotates in the counterclockwise direction W2 relative to the second adjusting member 312, the guide surface 303 presses the elastic tooth 32, so that the elastic tooth 32 moves elastically away from the ratchet tooth 221.

[0137] Understandably, in the initial state, the elastic tooth 32 extends out of the clearance groove 302 along the axial direction Y toward the distal end b, so that the elastic tooth 32 can mesh between two adjacent ratchet teeth 221.

[0138] The elastic tooth 32 and the guide surface 303 of the slot 301 are arranged in a clockwise direction W1. Thus, when the first adjusting member 311 rotates counterclockwise W2 relative to the housing assembly 10 under the action of a second external force, the second adjusting member 312 can first rotate a certain angle counterclockwise W2 relative to the first adjusting member 311, specifically, the latch 3121 rotates a certain angle circumferentially W within the slot 301. During this process, the guide surface 303 rotates counterclockwise W2 relative to the elastic tooth 32, causing the elastic tooth 32 to elastically move onto the guide surface 303. Guided by the guide surface 303, the elastic tooth 32 can then elastically move away from the ratchet tooth 221, causing at least a portion of the elastic tooth 32 to retract into the slot 301. Thus, after the buckle 3121 rotates a certain angle in the slot 301 along the circumferential direction W, when the buckle 3121 abuts against the second inner wall of the slot 301 along the circumferential direction W, the first adjusting member 311 can drive the second adjusting member 312 to rotate in the counterclockwise direction W2, thereby causing the adjusting component 30 to rotate in the counterclockwise direction W2 relative to the housing component 10 and the clutch component 20 for scale adjustment.

[0139] This configuration allows the adjusting component 30 to rotate counterclockwise W2 relative to the housing component 10 and the clutch component 20 under the action of a second external force.

[0140] It should be noted that when the second external force is removed, the elastic tooth 32 elastically resets along the guide surface 303, so that it extends out of the slot 301 along the axial direction Y toward the distal end b, and meshes between the two adjacent ratchet teeth 221.

[0141] The guide surface 303 can be either an arc-shaped surface or an inclined surface.

[0142] Specifically, the knob 80 is used to engage with the first adjusting part 3111 of the first adjusting member 311 in a circumferential W-direction limiting manner.

[0143] In some embodiments, please refer to the following: Figures 11 to 13 And in conjunction with other accompanying drawings. The outer peripheral wall of the push rod assembly 60 is provided with a first threaded groove 601, and in the extending direction of the first threaded groove 601, a third limiting portion 61 is formed on the inner wall of the end of the first threaded groove 601 facing the proximal end a. The memory element 70 is sleeved on the outer periphery of the push rod assembly 60, and the inner peripheral wall of the memory element 70 is formed with a first thread 71, which is threadedly engaged with the first threaded groove 601.

[0144] Thus, when the memory element 70 rotates relative to the push rod assembly 60, the first thread 71 rotates along the first thread groove 601, causing the memory element 70 to move relative to the push rod assembly 60 along the axial direction Y. When the memory element 70 rotates relative to the push rod assembly 60 in the clockwise direction W1, the first thread 71 of the memory element 70 can abut against the third limiting part 61, so that the memory element 70 is limited to the third limiting part 61 in the clockwise direction W1.

[0145] In some embodiments, please refer to the following: Figure 12 , Figure 13 , Figure 18 and Figure 19 And in conjunction with other accompanying figures. Figure 18 This is a perspective view of the rotating component 21 of the syringe drive mechanism 100 provided in some embodiments of this application. Figure 19 This is a structural diagram of the plunger assembly 60 and the rotating member 21 of the syringe drive mechanism 100 provided in some embodiments of this application. The outer peripheral wall of the plunger assembly 60 is provided with a sliding groove 602 extending along the axial direction Y. The sliding groove 602 disconnects the first threaded groove 601 on the plunger assembly 60, that is, the first threaded groove 601 and the sliding groove 602 are connected.

[0146] The clutch assembly 20 is sleeved outside the push rod assembly 60, and the inner peripheral wall of the clutch assembly 20 has a protrusion 211. The protrusion 211 is inserted into the slide groove 602, and the protrusion 211 can slide relative to the slide groove 602 along the axial direction Y. In this way, the push rod assembly 60 can move relative to the housing assembly 10 and the clutch assembly 20 along the axial direction Y. In particular, the push rod assembly 60 can move relative to the clutch assembly 20 and the housing assembly 10 at its distal end b along the axial direction Y to realize the injection of medicine.

[0147] In some embodiments, please refer to the following: Figure 3 , Figure 4 , Figure 14 , Figure 18 and Figure 20 And in conjunction with other accompanying figures. Figure 20 for Figure 4 Enlarged view at point D. The clutch assembly 20 includes a rotating member 21, a clutch member 22, and a first elastic member 23. The rotating member 21 is rotatably disposed within the housing assembly 10, sleeved on the push rod assembly 60, and engaged with the push rod assembly 60 in a circumferential W-direction limiting engagement. The clutch member 22 is sleeved on the push rod assembly 60 and engaged with the first limiting portion 111 in a circumferential W-direction limiting engagement. The clutch member 22 is used for the circumferential W-direction limiting engagement with the rotating member 21. The first elastic member 23 abuts against the clutch member 22 and the rotating member 21. An adjusting assembly 30 is disposed within the housing assembly 10 and is movably disposed along the axial Y-direction. The adjusting assembly 30 is configured to move relative to the housing assembly 10 at its distal end b under the action of a first external force to compress the clutch member 22 and drive the clutch member 22 away from the first limiting portion 111.

[0148] Specifically, the clutch element 22 is located at the proximal end a of the rotating element 21, and the adjusting component 30 is located at the proximal end a of the clutch element 22. Specifically, the ratchet tooth 221 is located at the proximal end a of the clutch element 22.

[0149] Understandably, the outer peripheral wall of the clutch 22 is provided with a plurality of fourth limiting portions 222, which are arranged circumferentially W. There are also a plurality of first limiting portions 111, which are also arranged circumferentially W. Each fourth limiting portion 222 is positioned circumferentially W between two adjacent first limiting portions 111, and each first limiting portion 111 is positioned circumferentially W between two adjacent fourth limiting portions 222. This allows the clutch 22 and the housing assembly 10 to be engaged circumferentially W in their initial state.

[0150] Under the action of the first external force, the adjusting component 30 moves relative to the housing assembly 10 along the axial direction Y toward the distal end b to compress the clutch 22. At this time, the fourth limiting part 222 moves relative to the first limiting part 111 along the axial direction Y toward the distal end b to disengage from the first limiting part 111. In this way, the housing assembly 10 and the clutch 22 can be released from their circumferential W-direction restriction.

[0151] With this configuration, when the adjusting component 30 moves relative to the housing assembly 10 along the axial direction Y towards the distal end b under the action of the first external force, the circumferential W limit between the clutch 22 and the housing assembly 10 is released. Thus, under the driving force of the reset component 50, the adjusting component 30, clutch 22, rotating component 21, push rod assembly 60, memory component 70, and numerical rotating cylinder 40 can rotate together along the counterclockwise direction W2 relative to the housing assembly 10, and the push rod assembly 60 moves relative to the housing assembly 10 along the axial direction Y towards the distal end b, thereby realizing the injection of medicine.

[0152] It should be further noted that the adjusting component 30 is located at the proximal end of the clutch assembly 20. When the first external force is applied, the adjusting component 30 presses the clutch member 22 distally along the axial direction Y, so that the first elastic member 23 stores force.

[0153] When the first external force is removed, under the elastic action of the first elastic member 23, the clutch member 22 can move relative to the housing assembly 10 along the axial direction Y toward the proximal end a, so as to be circumferentially limited on the first limiting part 111. Furthermore, the adjusting assembly 30 is pushed by the clutch member 22 and moves back to its original position along the axial direction Y toward the proximal end a.

[0154] In some embodiments, please refer to the following: Figure 3 , Figure 4 , Figures 18 to 20 And in conjunction with other accompanying drawings. The rotating component 21, the clutch component 22, and the first elastic component 23 are all sleeved on the outside of the push rod assembly 60. Specifically, the rotating component 21 has the aforementioned protrusion 211 on its inner peripheral wall.

[0155] In some embodiments, please refer to the following: Figure 3 , Figure 4 and Figure 7 The injection device may also include a button 90, which is movably disposed on the housing assembly 10 and abuts against the adjustment assembly 30 at its distal end b along the axial direction Y. Specifically, the button 90 abuts against the proximal end a of the first adjustment portion 3111 of the first adjustment member 311.

[0156] Based on this, the first external force is applied by pressing the button 90 towards the distal end b along the axial direction Y. By pressing the button 90 towards the distal end b, the adjusting component 30 can drive the clutch 22 to move along the axial direction Y towards the distal end b, causing the clutch 22 to disengage from the first limiting part 111.

[0157] In some embodiments, please refer to the following: Figure 3 , Figure 4 and Figure 7 The injection device may also include a second elastic element 110, which abuts against the button 90 and the housing assembly 10 so that after the first external force is removed, the button 90 can be reset along the axial Y towards the proximal end a under the elastic force of the second elastic element 110, so as to remove the pressing action on the adjustment assembly 30 moving along the axial Y towards the distal end b.

[0158] In some embodiments, the button 90 is engaged with the adjustment component 30 so that when the first external force is removed and the button 90 moves to reset along the axial direction Y toward the proximal end a, the adjustment component 30 can also move to reset along the axial direction Y toward the proximal end a under the action of the button 90.

[0159] In some embodiments, please refer to the following: Figure 14 and Figure 18Furthermore, in conjunction with other accompanying drawings, the outer peripheral wall of the clutch 22 is provided with a plurality of first gear teeth 223 arranged circumferentially W, and the inner peripheral wall of the rotating member 21 is provided with a plurality of second gear teeth 212 arranged circumferentially W. The first gear teeth 223 are limited to the position between two adjacent second gear teeth 212 along the circumferential direction W, and the second gear teeth 212 are limited to the position between two adjacent first gear teeth 223 along the circumferential direction W. In this way, the rotating member 21 and the clutch 22 can be limited in the circumferential direction W.

[0160] The fourth limiting part 222 is provided at the proximal end a of the first gear tooth 223, and the second gear tooth 212 is provided at the proximal end a of the protrusion 211.

[0161] In some embodiments, the reset member 50 is an elastic structure. In the axial direction Y, the proximal end a of the reset member 50 is connected to the housing assembly 10, and the distal end b of the reset member 50 is connected to the adjustment assembly 30. The reset member 50 provides the adjustment assembly 30 with an elastic force along the axial direction Y toward the proximal end a.

[0162] Thus, when the first external force is removed, under the action of the reset member 50, the adjusting component 30 moves to reset along the axial direction Y toward the proximal end a, which facilitates the clutch member 22 to move to reset along the axial direction Y toward the proximal end a, so as to cooperate with the first limiting part 111 in the circumferential direction W.

[0163] In some embodiments, please refer to the following: Figure 1 and Figure 2 And in conjunction with other accompanying drawings. The vial assembly 200 is detachably mounted on the housing assembly 10.

[0164] In some embodiments, please refer to the following: Figure 20 and Figure 21 And in conjunction with other accompanying figures. Figure 20 In the middle, the vial assembly 200 is mounted on the syringe drive mechanism 100. Figure 21 This is a partial cross-sectional view of a syringe drive mechanism 100 provided in some embodiments of this application without the vial assembly 200 installed. A rotating member 21 and a clutch member 22 are spaced apart, and a push rod assembly 60 is configured to rotate clockwise W1 relative to the housing assembly 10. The rotating member 21 is axially movable within the housing assembly 10 and configured to move proximal to end a under pressure from the vial assembly 200 to engage with the clutch member 22 in a circumferential W-direction limiting manner.

[0165] Understandably, when the vial assembly 200 is installed on the housing assembly 10, such as Figure 4 and Figure 20In conjunction with other accompanying drawings, the vial assembly 200 applies pressure to the rotating member 21 along the axial direction Y towards the proximal end a, causing the rotating member 21 to move along the axial direction Y towards the proximal end a, thus enabling the rotating member 21 and the clutch member 22 to engage in a circumferential W-direction limiting engagement. In this way, in the initial state, the clutch member 22 and the housing assembly 10 are engaged in a circumferential W-direction limiting engagement, and the rotating member 21 and the clutch member 22 are also engaged in a circumferential W-direction limiting engagement. Based on this, after adjusting the scale, the clutch member 22 is driven to disengage from the first limiting part 111 by the action of a first external force. The adjusting assembly 30, the clutch member 22, the rotating member 21, the numerical rotating cylinder 40, the memory unit 70, and the push rod assembly 60 can all rotate counterclockwise W2 relative to the housing assembly 10 under the drive of the reset member 50. The push rod assembly 60 moves along the axial direction Y towards the distal end b relative to the housing assembly 10 and the clutch assembly 20, thereby realizing the injection of the medicine. During the injection of the drug, the memory element 70 moves along the axial direction Y toward the distal end b relative to the housing assembly 10 and the clutch assembly 20, together with the push rod assembly 60.

[0166] Understandably, the initial state of the injection device is the initial state after the syringe drive mechanism 100 and the vial assembly 200 are installed.

[0167] After the medicine in the vial assembly 200 has been injected, the vial assembly 200 can be detached from the housing assembly 10. Then, the push rod assembly 60 is rotated clockwise W1 relative to the housing assembly 10, so that the push rod assembly 60 moves axially Y towards the proximal end a, to reset and retract into the housing assembly 10. During this process, if both the clutch 22 and the rotating member 21 rotate clockwise W1 with the push rod assembly 60, and the adjusting component 30 is limited to the clutch assembly 20 in the counterclockwise W2 direction, the clutch 22 will be unable to rotate clockwise under the limiting action of the adjusting component 30, thus failing to reset the push rod assembly 60. In this embodiment, when the vial assembly 200 is not installed with the housing assembly 10, if Figure 21 As shown in the accompanying drawings and in conjunction with other figures, the pressure applied by the vial assembly 200 to the rotating member 21 along the axial direction Y towards the proximal end a is removed. Under the elastic action of the first elastic member 23, the rotating member 21 moves along the axial direction Y towards the distal end b, so that the rotating member 21 and the clutch member 22 are spaced apart. Thus, the rotating member 21 and the clutch member 22 do not form a circumferential W-shaped limit, and the rotating member 21 can rotate relative to the clutch member 22. In this way, when the rotating member 21 rotates with the push rod assembly 60 in the clockwise direction W1 relative to the housing assembly 10, the clutch member 22 will not rotate in the clockwise direction W1 along with the rotating member 21. This prevents the clutch member 22 and the adjusting assembly 30 from obstructing the rotation of the push rod assembly 60, thereby allowing the push rod assembly 60 to reset. Thus, the syringe drive mechanism 100 can continue to be used after replacing the vial assembly 200 or the vial 220 inside the vial assembly 200, thereby giving the syringe drive mechanism 100 a reusable effect.

[0168] It should also be noted that when the vial assembly 200 is not installed with the housing assembly 10, when the push rod assembly 60 is rotated clockwise W1 relative to the housing assembly 10, since the rotating part 21 and the clutch part 22 do not form a circumferential W limit, the clutch part 22 will not rotate clockwise W1 together with the rotating part 21. Therefore, the adjusting assembly 30 will not rotate clockwise W1 with the push rod assembly 60. Thus, under the circumferential W limit of the adjusting assembly 30, the memory element 70 will not rotate clockwise W1 as well. This causes the push rod assembly 60 to rotate axially toward the proximal end a relative to the memory element 70, so that the memory element 70 can also be reset relative to the push rod assembly 60 after the push rod assembly 60 resets. Thus, both the push rod assembly 60 and the memory element 70 are reset to their initial positions. When the push rod assembly 60 and the memory element 70 are in their initial positions, the distance between the memory element 70 and the third limiting part 61 in the axial Y direction can be used to indicate the axial Y height of the medicine in the vial assembly 200.

[0169] This configuration ensures that when the vial assembly 200 is installed on the housing assembly 10, the rotating member 21 and the clutch member 22 are engaged in a circumferential W-direction limiting fit. When the vial assembly 200 is not installed on the housing assembly 10, the circumferential W-direction limiting fit of the rotating member 21 and the clutch member 22 is released.

[0170] In some embodiments, please refer to the following: Figure 3 , Figure 4 and Figure 22 And in conjunction with other accompanying figures. Figure 22 This is a perspective view of the movable member 12 of the syringe drive mechanism 100 provided in some embodiments of this application. The housing assembly 10 includes a housing 11 and a movable member 12. The housing 11 is used to connect with the vial assembly 200, and a first limiting part 111 and a second limiting part 141 are both provided on the housing 11. The movable member 12 is circumferentially limited on the housing 11 and is threadedly connected to the push rod assembly 60. A rotating member 21 is rotatably provided on the movable member 12, and the movable member 12 and the rotating member 21 are limited and engaged along the axial direction Y. The movable member 12 is movable along the axial direction Y on the housing 11 and is used to abut against the vial assembly 200 at its distal end b.

[0171] Specifically, the movable part 12 is sleeved outside the push rod assembly 60 and is threadedly connected to the push rod assembly 60.

[0172] With this configuration, when the vial assembly 200 is mounted on the housing 11, the vial assembly 200 abuts against the moving member 12 along the axial direction Y towards the proximal end a, causing the rotating member 21 to move along the axial direction Y towards the proximal end a under the drive of the moving member 12, so as to engage with the clutch member 22 in a circumferential W-direction limiting fit. In this way, the adjusting component 30, the numerical rotating cylinder 40, the memory unit 70, the push rod assembly 60, the clutch member 22, and the rotating member 21 can rotate together in a counterclockwise direction W2 relative to the housing assembly 10, so as to realize the movement of the push rod assembly 60 along the axial direction Y towards the distal end b, thereby realizing the injection of medicine.

[0173] When the medicine bottle 220 is not installed on the housing 11, the abutment action of the medicine bottle assembly 200 against the moving part 12 is removed. Under the action of the first elastic member 23, the rotating part 21 and the moving part 12 can move together along the axial direction Y towards the far end b, so that the circumferential W limit between the rotating part 21 and the clutch part 22 is removed, thereby facilitating the push rod assembly 60 to rotate in the clockwise direction W1 to achieve reset.

[0174] Specifically, the numerical rotating cylinder 40 is rotatably disposed inside the housing 11, and the inner peripheral wall of the housing 11 is provided with a first limiting part 111 and a second thread 112.

[0175] In some embodiments, the movable member 12 can be used to abut against the mounting bracket 210 of the vial assembly 200 along the axial direction Y toward the distal end b, such that when the mounting bracket 210 is mounted on the housing assembly 10, the clutch member 22 and the rotating member 21 can achieve circumferential W-limiting.

[0176] In some embodiments, the movable member 12 can be used to abut against the medicine bottle 220 of the medicine bottle assembly 200 along the axial direction Y toward the distal end b, such that when both the mounting bracket 210 and the medicine bottle 220 are mounted on the housing assembly 10, the clutch member 22 and the rotating member 21 achieve circumferential W-limiting.

[0177] In some embodiments, please refer to the following: Figure 2 , Figure 3 and Figure 23 And in conjunction with other accompanying figures. Figure 23 This is a perspective view of the fixing member 13 of the syringe drive mechanism 100 provided in some embodiments of this application. The housing assembly 10 also includes the fixing member 13, which is fixed to the housing 11. The movable member 12 is circumferentially confined on the fixing member 13 and is movable relative to the movable member 12 in the axial direction Y. The fixing member 13 is used for detachably connecting the vial assembly 200.

[0178] This configuration allows the syringe drive mechanism 100 to be detachably connected to the vial assembly 200 via the fastener 13, thereby enabling the replacement of the vial assembly 200 or the vial 220 and achieving the reusability of the syringe drive mechanism 100.

[0179] Specifically, in the axial direction Y, the fastener 13 is located at the distal end b of the housing 11.

[0180] In some embodiments, please refer to the following: Figure 3 , Figure 4 and Figure 7 And in conjunction with other accompanying drawings. The housing assembly 10 may also include a limiting member 14. In the axial direction Y, the limiting member 14 is provided at the proximal end a of the housing 11. Furthermore, a second limiting portion 141 is provided on the limiting member 14.

[0181] Please see Figure 1 The injection device provided in this application embodiment includes a syringe drive mechanism 100, a vial assembly 200, and an injection needle 300, as shown in the accompanying drawings. The vial assembly 200 includes a mounting bracket 210 and a vial 220. The mounting bracket 210 is detachably mounted on the housing assembly 10, and the vial 220 is detachably disposed on the mounting bracket 210. The injection needle 300 is detachably mounted on the mounting bracket 210 and communicates with the vial 220. The syringe drive mechanism 100 in this embodiment is the same as the syringe drive mechanism 100 in the above embodiments; please refer to the relevant descriptions of the syringe drive mechanism 100 in the above embodiments for details, which will not be repeated here.

[0182] Specifically, when the push rod assembly 60 moves along the axial direction Y toward the distal end b relative to the housing assembly 10, the push rod assembly 60 pushes the piston 230 inside the vial 220, so that the piston 230 squeezes the medicine inside the vial 220 through the injection needle 300 to achieve the injection operation.

[0183] The injection device provided in this application adopts the syringe drive mechanism 100 involved in the above embodiments. After the medicine in the vial assembly 200 is used up, the adjustment component 30 achieves self-locking. The adjustment component 30 cannot continue to rotate relative to the clutch component 20 in the clockwise direction W1, nor can it rotate in the counterclockwise direction W2, so it cannot continue to perform scale adjustment and injection work. This can reduce the risk of accidental injection after the medicine in the vial assembly 200 is used up.

[0184] Furthermore, on the one hand, it facilitates the replacement of the injection needle 300, allowing the user to change the injection needle 300 each time the syringe drive mechanism 100 is used. On the other hand, it facilitates the replacement of the vial assembly 200 or the vial 220, allowing the vial assembly 200 to be detached from the housing assembly 10 after the medication in the vial 220 has been injected, and then the entire vial assembly 200 or the vial 220 can be replaced. Thus, the syringe drive mechanism 100 has a reusable function, helping to save resources.

[0185] In some embodiments, please refer to the following: Figure 1 and Figure 3 And in conjunction with other accompanying drawings. The injection device may also include a pen cap 400, which is used to mount on the housing assembly 10 to cover the injection needle 300.

[0186] Based on the above structure, the working principle of the injection device is as follows:

[0187] In its initial state, the injection device has the vial assembly 200 mounted on the fixing member 13. The vial assembly 200 abuts against the moving member 12 along the axial direction Y towards its proximal end a, so that the clutch member 22 and the rotating member 21 are engaged in a circumferential W-direction limiting fit. The clutch member 22 is circumferentially limited to the first limiting part 111, and the elastic tooth 32 extends out of the slot 301 along the axial direction Y towards its distal end b, so as to be limited to the clutch assembly 20 in a counterclockwise direction W2. The numerical rotating cylinder 40 is limited to the second limiting part 141 in a counterclockwise direction W2, so that the scale displayed by the numerical rotating cylinder 40 is 0. The memory element 70 and the third limiting part 61 are spaced apart along the axial direction Y, and the distance between the memory element 70 and the third limiting part 61 in the axial direction Y is set by the axial Y height of the liquid in the vial assembly 200.

[0188] When using the injection device, the knob 80 can be rotated clockwise in the direction W1 (the second external force is applied), so that the elastic tooth 32 moves elastically relative to the ratchet tooth 221 in the clockwise direction W1. In this way, the first adjusting member 311, the second adjusting member 312, the numerical rotating cylinder 40 and the memory unit 70 rotate clockwise in the direction W1 relative to the housing assembly 10, the clutch assembly 20 and the push rod assembly 60, so that the numerical rotating cylinder 40 moves in the axial direction Y toward the distal end b relative to the housing assembly 10 and the adjusting assembly 30, and the memory unit 70 moves in the axial direction Y toward the proximal end a relative to the housing assembly 10 and the adjusting assembly 30. Alternatively, the knob 80 can be rotated counterclockwise W2 (under the action of a second external force). This causes the first adjusting member 311 to rotate counterclockwise W2 relative to the housing assembly 10. Simultaneously, the first adjusting member 311 first rotates counterclockwise W2 relative to the second adjusting member 312, causing the elastic tooth 32 to elastically retract into the slot 301 away from the ratchet tooth 221. This reduces the engagement depth between the elastic tooth 32 and the ratchet tooth 221, causing the elastic tooth 32 to disengage from the ratchet tooth 221 or be in a semi-engaged state. The first adjusting member 311 then drives the second adjusting member 312 to rotate counterclockwise W2, allowing the adjusting assembly 30 to rotate counterclockwise W2 relative to the housing assembly 10, the clutch assembly 20, and the push rod assembly 60. This enables scale adjustment of the injection device.

[0189] Then, pressing button 90 (with the first external force applied) causes the adjusting component 30 to move axially Y toward the distal end b and press the clutch 22, thereby disengaging the clutch 22 from the first limiting part 111. The reset component 50 resets, causing the adjusting component 30, the numerical rotating cylinder 40, the memory component 70, the push rod assembly 60, the clutch 22, the first elastic component 23, and the rotating component 21 to rotate together in the counterclockwise direction W2 relative to the housing assembly 10. The push rod assembly 60 moves axially Y toward the distal end b relative to the housing assembly 10, the clutch assembly 20, and the adjusting component 30 to realize the injection of the medicine.

[0190] If the medicine in vial 220 is not completely injected and another injection is needed, the injection needle 300 can be replaced, and the knob 80 can be rotated again to adjust the scale. Then, the button 90 can be pressed to move the push rod assembly 60 along the axial direction Y towards the distal end b relative to the housing assembly 10 to perform another injection.

[0191] When the knob 80 cannot be rotated, it indicates that the memory element 70 is limited to the third limiting part 61 of the push rod assembly 60 in the clockwise direction W1, and the medicine in the medicine bottle 220 has been injected. At this time, the medicine bottle assembly 200 can be disassembled, and the rotating part 21 and the moving part 12 disengage from the clutch 22 under the action of the first elastic member 23, and the circumferential W engagement between the rotating part 21 and the clutch 22 is removed. Then, the push rod assembly 60 can be rotated in the clockwise direction W1 to reset the push rod assembly 60 to the proximal end a along the axial direction Y and move it into the housing assembly 10. At this time, the memory element 70 will not rotate with the push rod assembly 60 under the limiting action of the adjusting component 30, so that the push rod assembly 60 can still move relative to the memory element 70 in the proximal end a along the axial direction Y, so that the memory element 70 can return to the initial position. At this time, the distance between the memory element 70 and the third limiting part 61 can still indicate the height of the medicine in the medicine bottle 220. Based on this, the vial assembly 200 or the vial 220 can be replaced. After replacement, the vial assembly 200 can be installed on the housing assembly 10, so that the above-mentioned scale adjustment and medicine injection work can be repeated.

[0192] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A syringe drive mechanism for use in an injection device, the injection device having proximal and distal ends at opposite axial ends; characterised in that, The syringe driving mechanism includes: A housing assembly for connection with a medicine bottle assembly, the housing assembly having a first limiting part and a second limiting part; A clutch assembly is disposed within the housing assembly and engages with the first limiting portion in a circumferential limiting manner, and is configured to disengage from the first limiting portion under the action of a first external force; An adjustment component is rotatably disposed within the housing assembly and configured to be limited to the clutch assembly in a counterclockwise direction, and further configured to be rotatable relative to the clutch assembly under the action of a second external force; A numerical rotary cylinder is rotatably threaded into the housing assembly; the numerical rotary cylinder is sleeved outside the adjustment assembly and circumferentially limited on the adjustment assembly, and is configured to move axially relative to the housing assembly and the adjustment assembly as it rotates with the adjustment assembly to adjust the scale; A reset member is connected between the housing assembly and the adjustment assembly and configured to provide the adjustment assembly with a driving force for rotation in the counterclockwise direction, so that the numerical rotating drum is limited to the second limiting portion in the counterclockwise direction; A push rod assembly, threaded to the housing assembly and circumferentially positioned on the clutch assembly, is configured to move toward the distal end relative to the housing assembly and the clutch assembly when rotated in the counterclockwise direction to drive the medicine in the vial assembly; A memory element is threadedly connected to the push rod assembly and circumferentially confined within the adjusting assembly, and configured to move axially relative to the adjusting assembly and the push rod assembly when rotating relative to the push rod assembly; the push rod assembly is provided with a third limiting portion for limiting the clockwise rotational stroke of the memory element.

2. The syringe driving mechanism according to claim 1, characterized in that, The clutch assembly has a plurality of ratchet teeth arranged circumferentially at one end facing the proximal end, and the ratchet teeth are inclined in the clockwise direction; The adjustment component includes: An adjustment body is rotatably disposed within the housing assembly and located at the proximal end of the clutch assembly; the numerical rotating cylinder is sleeved outside the adjustment body, and the adjustment body is connected to the reset member and respectively engages with the numerical rotating cylinder and the memory member in a circumferential limiting manner; An elastic tooth is disposed on the adjusting body and extends out of the adjusting body toward the distal end; the elastic tooth elastically engages between two adjacent ratchet teeth to be confined on the ratchet teeth in the counterclockwise direction, and is used to elastically move relative to the ratchet teeth in the clockwise direction under the action of the second external force.

3. The syringe driving mechanism according to claim 2, characterized in that, The regulating body includes: The first adjusting member is circumferentially limited to the memory element; The second adjusting member is sleeved outside the first adjusting member; the elastic tooth is provided on the second adjusting member, the second adjusting member is connected to the reset member, and the numerical rotating cylinder is sleeved outside the second adjusting member and is circumferentially limited to cooperate with the second adjusting member; In this configuration, one of the first adjusting member and the second adjusting member is provided with a buckle, and the other is provided with a slot; the buckle is confined within the slot in both the circumferential and axial directions, and in the circumferential direction, the size of the slot is larger than the size of the buckle; the first adjusting member is configured to drive the elastic tooth to move elastically away from the ratchet tooth when it rotates relative to the second adjusting member in the counterclockwise direction under the action of the second external force.

4. The syringe driving mechanism according to claim 3, characterized in that, The first adjusting member includes: The first adjustment part is circumferentially limited and cooperates with the memory element, and the second adjustment part is sleeved outside the first adjustment part. One of the first adjustment part and the second adjustment part is provided with the buckle, and the other is provided with the slot. The second adjustment part is located at the end of the first adjustment part facing the distal end. The second adjustment part is provided with a relief groove extending through it in the axial direction. The elastic tooth extends out of the relief groove towards the distal end. The groove wall of the relief groove is provided with a guide surface. The guide surface is configured to squeeze the elastic tooth when the first adjustment part rotates relative to the second adjustment member in the counterclockwise direction, so that the elastic tooth moves elastically away from the ratchet tooth.

5. The syringe driving mechanism according to any one of claims 1-4, characterized in that, The outer peripheral wall of the push rod assembly is provided with a first threaded groove, and in the extending direction of the first threaded groove, the inner wall of the end of the first threaded groove facing the proximal end forms the third limiting part. The memory element is sleeved on the outer periphery of the push rod assembly, and the inner peripheral wall of the memory element is formed with a first thread, which engages with the first thread groove.

6. The syringe driving mechanism according to any one of claims 1-4, characterized in that, The clutch assembly includes: A rotating component is rotatably disposed within the housing assembly and sleeved outside the push rod assembly, and is circumferentially limited in fit with the push rod assembly; A clutch element is sleeved outside the push rod assembly and engages with the first limiting part in a circumferential limiting manner; the clutch element is used to engage with the rotating part in a circumferential limiting manner. The first elastic element abuts against the clutch element and the rotating element; The adjusting component is axially movable within the housing assembly and configured to move toward the distal end relative to the housing assembly under the action of the first external force, so as to squeeze and drive the clutch to disengage from the first limiting portion.

7. The syringe driving mechanism according to claim 6, characterized in that, The rotating component and the clutch component are spaced apart, and the push rod assembly is configured to rotate relative to the housing assembly in the clockwise direction; The rotating member is axially movable within the housing assembly and configured to move toward the proximal end under pressure from the vial assembly to engage with the clutch member in a circumferentially limited manner.

8. The syringe driving mechanism according to claim 7, characterized in that, The housing assembly includes: A housing for connecting to the vial assembly, wherein both the first limiting part and the second limiting part are provided on the housing; The movable component is circumferentially positioned on the housing and threadedly connected to the push rod assembly, and axially positioned and engaged with the rotating component; the movable component is axially movable on the housing and is used to abut against the medicine bottle assembly at the distal end.

9. The syringe driving mechanism according to claim 8, characterized in that, The housing assembly further includes a fixing member fixed to the housing, and the movable member is circumferentially limited to the fixing member. The fixing member is used to detachably connect the vial assembly.

10. An injection device, characterized in that, include: The syringe drive mechanism according to any one of claims 1-9; A medicine bottle assembly includes a mounting bracket detachably mounted on the housing assembly and a medicine bottle detachably disposed on the mounting bracket; The injection needle is detachably mounted on the mounting bracket and communicates with the vial.

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